factor feedback model: Topics by Science.gov

Low-Cloud Feedbacks from Cloud-Controlling Factors: A Review

DOE PAGES

Klein, Stephen A.; Hall, Alex; Norris, Joel R.; ...

2017-10-24

Here, the response to warming of tropical low-level clouds including both marine stratocumulus and trade cumulus is a major source of uncertainty in projections of future climate. Climate model simulations of the response vary widely, reflecting the difficulty the models have in simulating these clouds. These inadequacies have led to alternative approaches to predict low-cloud feedbacks. Here, we review an observational approach that relies on the assumption that observed relationships between low clouds and the “cloud-controlling factors” of the large-scale environment are invariant across time-scales. With this assumption, and given predictions of how the cloud-controlling factors change with climate warming,more » one can predict low-cloud feedbacks without using any model simulation of low clouds. We discuss both fundamental and implementation issues with this approach and suggest steps that could reduce uncertainty in the predicted low-cloud feedback. Recent studies using this approach predict that the tropical low-cloud feedback is positive mainly due to the observation that reflection of solar radiation by low clouds decreases as temperature increases, holding all other cloud-controlling factors fixed. The positive feedback from temperature is partially offset by a negative feedback from the tendency for the inversion strength to increase in a warming world, with other cloud-controlling factors playing a smaller role. A consensus estimate from these studies for the contribution of tropical low clouds to the global mean cloud feedback is 0.25 ± 0.18 W m –2 K –1 (90% confidence interval), suggesting it is very unlikely that tropical low clouds reduce total global cloud feedback. Because the prediction of positive tropical low-cloud feedback with this approach is consistent with independent evidence from low-cloud feedback studies using high-resolution cloud models, progress is being made in reducing this key climate uncertainty.« less
Low-Cloud Feedbacks from Cloud-Controlling Factors: A Review

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klein, Stephen A.; Hall, Alex; Norris, Joel R.

Here, the response to warming of tropical low-level clouds including both marine stratocumulus and trade cumulus is a major source of uncertainty in projections of future climate. Climate model simulations of the response vary widely, reflecting the difficulty the models have in simulating these clouds. These inadequacies have led to alternative approaches to predict low-cloud feedbacks. Here, we review an observational approach that relies on the assumption that observed relationships between low clouds and the “cloud-controlling factors” of the large-scale environment are invariant across time-scales. With this assumption, and given predictions of how the cloud-controlling factors change with climate warming,more » one can predict low-cloud feedbacks without using any model simulation of low clouds. We discuss both fundamental and implementation issues with this approach and suggest steps that could reduce uncertainty in the predicted low-cloud feedback. Recent studies using this approach predict that the tropical low-cloud feedback is positive mainly due to the observation that reflection of solar radiation by low clouds decreases as temperature increases, holding all other cloud-controlling factors fixed. The positive feedback from temperature is partially offset by a negative feedback from the tendency for the inversion strength to increase in a warming world, with other cloud-controlling factors playing a smaller role. A consensus estimate from these studies for the contribution of tropical low clouds to the global mean cloud feedback is 0.25 ± 0.18 W m –2 K –1 (90% confidence interval), suggesting it is very unlikely that tropical low clouds reduce total global cloud feedback. Because the prediction of positive tropical low-cloud feedback with this approach is consistent with independent evidence from low-cloud feedback studies using high-resolution cloud models, progress is being made in reducing this key climate uncertainty.« less
Confounding factors in determining causal soil moisture-precipitation feedback

NASA Astrophysics Data System (ADS)

Tuttle, Samuel E.; Salvucci, Guido D.

2017-07-01

Identification of causal links in the land-atmosphere system is important for construction and testing of land surface and general circulation models. However, the land and atmosphere are highly coupled and linked by a vast number of complex, interdependent processes. Statistical methods, such as Granger causality, can help to identify feedbacks from observational data, independent of the different parameterizations of physical processes and spatiotemporal resolution effects that influence feedbacks in models. However, statistical causal identification methods can easily be misapplied, leading to erroneous conclusions about feedback strength and sign. Here, we discuss three factors that must be accounted for in determination of causal soil moisture-precipitation feedback in observations and model output: seasonal and interannual variability, precipitation persistence, and endogeneity. The effect of neglecting these factors is demonstrated in simulated and observational data. The results show that long-timescale variability and precipitation persistence can have a substantial effect on detected soil moisture-precipitation feedback strength, while endogeneity has a smaller effect that is often masked by measurement error and thus is more likely to be an issue when analyzing model data or highly accurate observational data.
Modeling trial by trial and block feedback in perceptual learning

PubMed Central

Liu, Jiajuan; Dosher, Barbara; Lu, Zhong-Lin

2014-01-01

Feedback has been shown to play a complex role in visual perceptual learning. It is necessary for performance improvement in some conditions while not others. Different forms of feedback, such as trial-by-trial feedback or block feedback, may both facilitate learning, but with different mechanisms. False feedback can abolish learning. We account for all these results with the Augmented Hebbian Reweight Model (AHRM). Specifically, three major factors in the model advance performance improvement: the external trial-by-trial feedback when available, the self-generated output as an internal feedback when no external feedback is available, and the adaptive criterion control based on the block feedback. Through simulating a comprehensive feedback study (Herzog & Fahle 1997, Vision Research, 37 (15), 2133–2141), we show that the model predictions account for the pattern of learning in seven major feedback conditions. The AHRM can fully explain the complex empirical results on the role of feedback in visual perceptual learning. PMID:24423783
Uncertain soil moisture feedbacks in model projections of Sahel precipitation

NASA Astrophysics Data System (ADS)

Berg, Alexis; Lintner, Benjamin R.; Findell, Kirsten; Giannini, Alessandra

2017-06-01

Given the uncertainties in climate model projections of Sahel precipitation, at the northern edge of the West African Monsoon, understanding the factors governing projected precipitation changes in this semiarid region is crucial. This study investigates how long-term soil moisture changes projected under climate change may feedback on projected changes of Sahel rainfall, using simulations with and without soil moisture change from five climate models participating in the Global Land Atmosphere Coupling Experiment-Coupled Model Intercomparison Project phase 5 experiment. In four out of five models analyzed, soil moisture feedbacks significantly influence the projected West African precipitation response to warming; however, the sign of these feedbacks differs across the models. These results demonstrate that reducing uncertainties across model projections of the West African Monsoon requires, among other factors, improved mechanistic understanding and constraint of simulated land-atmosphere feedbacks, even at the large spatial scales considered here.Plain Language SummaryClimate model projections of Sahel rainfall remain notoriously uncertain; understanding the physical processes responsible for this uncertainty is thus crucial. Our study focuses on analyzing the feedbacks of soil moisture changes on model projections of the West African Monsoon under global warming. Soil moisture-atmosphere interactions have been shown in prior studies to play an important role in this region, but the potential feedbacks of long-term soil moisture changes on projected precipitation changes have not been investigated specifically. To isolate these feedbacks, we use targeted simulations from five climate models, with and without soil moisture change. Importantly, we find that climate models exhibit soil moisture-precipitation feedbacks of different sign in this region: in some models soil moisture changes amplify precipitation changes </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012ASPC..465..404D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012ASPC..465..404D">Testing Feedback Models with Nearby Star Forming Regions</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Doran, E.; Crowther, P. 2012-12-01 The feedback from massive stars plays a crucial role in the evolution of galaxies. Accurate modelling of this feedback is essential in understanding distant star forming regions. Young nearby, high mass (> 104 M⊙) clusters such as R136 (in the 30 Doradus region) are ideal test beds for population synthesis since they host large numbers of spatially resolved massive stars at a pre-supernovae stage. We present a quantitative comparison of empirical calibrations of radiative and mechanical feedback from individual stars in R136, with instantaneous burst predictions from the popular Starburst99 evolution synthesis code. We find that empirical results exceed predictions by factors of ˜3-9, as a result of limiting simulations to an upper limit of 100 M⊙. 100-300 M⊙ stars should to be incorporated in population synthesis models for high mass clusters to bring predictions into close agreement with empirical results. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1353105-physics-model-based-nonlinear-actuator-trajectory-optimization-safety-factor-profile-feedback-control-advanced-scenario-development-diii','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1353105-physics-model-based-nonlinear-actuator-trajectory-optimization-safety-factor-profile-feedback-control-advanced-scenario-development-diii">Physics-model-based nonlinear actuator trajectory optimization and safety factor profile feedback control for advanced scenario development in DIII-D</a> <a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a> Barton, Justin E.; Boyer, Mark D.; Shi, Wenyu; ... 2015-07-30 DIII-D experimental results are reported to demonstrate the potential of physics-model-based safety factor profile control for robust and reproducible sustainment of advanced scenarios. In the absence of feedback control, variability in wall conditions and plasma impurities, as well as drifts due to external disturbances, can limit the reproducibility of discharges with simple pre-programmed scenario trajectories. The control architecture utilized is a feedforward + feedback scheme where the feedforward commands are computed off-line and the feedback commands are computed on-line. In this work, firstly a first-principles-driven (FPD), physics-based model of the q profile and normalized beta (β N) dynamics is embeddedmore » into a numerical optimization algorithm to design feedforward actuator trajectories that sheer the plasma through the tokamak operating space to reach a desired stationary target state that is characterized by the achieved q profile and β N. Good agreement between experimental results and simulations demonstrates the accuracy of the models employed for physics-model-based control design. Secondly, a feedback algorithm for q profile control is designed following a FPD approach, and the ability of the controller to achieve and maintain a target q profile evolution is tested in DIII-D high confinement (H-mode) experiments. The controller is shown to be able to effectively control the q profile when β N is relatively close to the target, indicating the need for integrated q profile and β N control to further enhance the ability to achieve robust scenario execution. Furthermore, the ability of an integrated q profile + β N feedback controller to track a desired target is demonstrated through simulation.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JAMES..10.1087H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JAMES..10.1087H">Methane Feedback on Atmospheric Chemistry: Methods, Models, and Mechanisms</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Holmes, Christopher D. 2018-04-01 The atmospheric methane (CH4) chemical feedback is a key process for understanding the behavior of atmospheric CH4 and its environmental impact. This work reviews how the feedback is defined and used, then examines the meteorological, chemical, and emission factors that control the feedback strength. Geographical and temporal variations in the feedback are described and explained by HOx (HOx = OH + HO2) production and partitioning. Different CH4 boundary conditions used by models, however, make no meaningful difference to the feedback calculation. The strength of the CH4 feedback depends on atmospheric composition, particularly the atmospheric CH4 burden, and is therefore not constant. Sensitivity tests show that the feedback depends very weakly on temperature, insolation, water vapor, and emissions of NO. While the feedback strength has likely remained within 10% of its present value over the industrial era and likely will over the twenty-first century, neglecting these changes biases our understanding of CH4 impacts. Most environmental consequences per kg of CH4 emissions, including its global warming potential (GWP), scale with the perturbation time, which may have grown as much as 40% over the industrial era and continues to rise. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23480111','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23480111">A student-centred feedback model for educators.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Rudland, Joy; Wilkinson, Tim; Wearn, Andy; Nicol, Pam; Tunny, Terry; Owen, Cathy; O'Keefe, Maree 2013-04-01 Effective feedback is instrumental to effective learning. Current feedback models tend to be educator driven rather than learner-centred, with the focus on how the supervisor should give feedback rather than on the role of the learner in requesting and responding to feedback. An alternative approach emphasising the theoretical principles of student-centred and self-regulated learning is offered, drawing upon the literature and also upon the experience of the authors. The proposed feedback model places the student in the centre of the feedback process, and stresses that the attainment of student learning outcomes is influenced by the students themselves. This model emphasises the attributes of the student, particularly responsiveness, receptiveness and reflection, whilst acknowledging the important role that the context and attributes of the supervisor have in influencing the quality of feedback. Educational institutions should consider strategies to encourage and enable students to maximise the many feedback opportunities available to them. As a minimum, educators should remind students about their central role in the feedback process, and support them to develop confidence in meeting this role. In addition, supervisors may need support to develop the skills to shift the balance of responsibility and support students in precipitating feedback moments. Research is also required to validate the proposed model and to determine how to support students to adopt self-regulatory learning, with feedback as a central platform. © Blackwell Publishing Ltd 2013. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27306646','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27306646">Factors influencing the effectiveness of audit and feedback: nurses' perceptions.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Christina, Venessa; Baldwin, Kathryn; Biron, Alain; Emed, Jessica; Lepage, Karine 2016-11-01 To explore the perceptions of nurses in an acute care setting on factors influencing the effectiveness of audit and feedback. Audit and feedback is widely used and recommended in nursing to promote evidence-based practice and to improve care quality. Yet the literature has shown a limited to modest effect at most. Audit and feedback will continue to be unreliable until we learn what influences its effectiveness. A qualitative study was conducted using individual, semi-structured interviews with 14 registered nurses in an acute care teaching hospital in Montreal, Canada. Three themes were identified: the relevance of audit and feedback, particularly understanding the purpose of audit and feedback and the prioritisation of audit criteria; the audit and feedback process, including its timing and feedback characteristics; and individual factors, such as personality and perceived accountability. According to participants, they were likely to have a better response to audit and feedback when they perceived that it was relevant and that the process fitted their preferences. This study benefits nursing leaders and managers involved in quality improvement by providing a better understanding of nurses' perceptions on how best to use audit and feedback as a strategy to promote evidence-based practice. © 2016 John Wiley & Sons Ltd. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15068593','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15068593">A feedback model of visual attention.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Spratling, M W; Johnson, M H 2004-03-01 Feedback connections are a prominent feature of cortical anatomy and are likely to have a significant functional role in neural information processing. We present a neural network model of cortical feedback that successfully simulates neurophysiological data associated with attention. In this domain, our model can be considered a more detailed, and biologically plausible, implementation of the biased competition model of attention. However, our model is more general as it can also explain a variety of other top-down processes in vision, such as figure/ground segmentation and contextual cueing. This model thus suggests that a common mechanism, involving cortical feedback pathways, is responsible for a range of phenomena and provides a unified account of currently disparate areas of research. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..MARB41003G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..MARB41003G">Distinguishing Feedback Mechanisms in Clock Models</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Golden, Alexander; Lubensky, David Biological oscillators are very diverse but can be classified based on dynamical motifs such as type of feedback. The S. Elongatus circadian oscillator is a novel circadian oscillator that can operate at constant protein number by modifying covalent states. It can be reproduced in vitro with only 3 different purified proteins: KaiA, KaiB, and KaiC. We use computational and analytic techniques to compare models of the S. Elongatus post-translational oscillator that rely on positive feedback with models that rely on negative feedback. We show that introducing a protein that binds competitively with KaiA to the KaiB-KaiC complex can distinguish between positive and negative feedback as the primary driver of the rhythm, which has so far been difficult to address experimentally. NSF Grant DMR-1056456. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29745850','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29745850">Feedback regulation in a stem cell model with acute myeloid leukaemia.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Jiao, Jianfeng; Luo, Min; Wang, Ruiqi 2018-04-24 The haematopoietic lineages with leukaemia lineages are considered in this paper. In particular, we mainly consider that haematopoietic lineages are tightly controlled by negative feedback inhibition of end-product. Actually, leukemia has been found 100 years ago. Up to now, the exact mechanism is still unknown, and many factors are thought to be associated with the pathogenesis of leukemia. Nevertheless, it is very necessary to continue the profound study of the pathogenesis of leukemia. Here, we propose a new mathematical model which include some negative feedback inhibition from the terminally differentiated cells of haematopoietic lineages to the haematopoietic stem cells and haematopoietic progenitor cells in order to describe the regulatory mechanisms mentioned above by a set of ordinary differential equations. Afterwards, we carried out detailed dynamical bifurcation analysis of the model, and obtained some meaningful results. In this work, we mainly perform the analysis of the mathematic model by bifurcation theory and numerical simulations. We have not only incorporated some new negative feedback mechanisms to the existing model, but also constructed our own model by using the modeling method of stem cell theory with probability method. Through a series of qualitative analysis and numerical simulations, we obtain that the weak negative feedback for differentiation probability is conducive to the cure of leukemia. However, with the strengthening of negative feedback, leukemia will be more difficult to be cured, and even induce death. In contrast, strong negative feedback for differentiation rate of progenitor cells can promote healthy haematopoiesis and suppress leukaemia. These results demonstrate that healthy progenitor cells are bestowed a competitive advantage over leukaemia stem cells. Weak g 1 , g 2 , and h 1 enable the system stays in the healthy state. However, strong h 2 can promote healthy haematopoiesis and suppress leukaemia. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29666593','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29666593">Interaction in Spoken Word Recognition Models: Feedback Helps.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Magnuson, James S; Mirman, Daniel; Luthra, Sahil; Strauss, Ted; Harris, Harlan D 2018-01-01 Human perception, cognition, and action requires fast integration of bottom-up signals with top-down knowledge and context. A key theoretical perspective in cognitive science is the interactive activation hypothesis: forward and backward flow in bidirectionally connected neural networks allows humans and other biological systems to approximate optimal integration of bottom-up and top-down information under real-world constraints. An alternative view is that online feedback is neither necessary nor helpful; purely feed forward alternatives can be constructed for any feedback system, and online feedback could not improve processing and would preclude veridical perception. In the domain of spoken word recognition, the latter view was apparently supported by simulations using the interactive activation model, TRACE, with and without feedback: as many words were recognized more quickly without feedback as were recognized faster with feedback, However, these simulations used only a small set of words and did not address a primary motivation for interaction: making a model robust in noise. We conducted simulations using hundreds of words, and found that the majority were recognized more quickly with feedback than without. More importantly, as we added noise to inputs, accuracy and recognition times were better with feedback than without. We follow these simulations with a critical review of recent arguments that online feedback in interactive activation models like TRACE is distinct from other potentially helpful forms of feedback. We conclude that in addition to providing the benefits demonstrated in our simulations, online feedback provides a plausible means of implementing putatively distinct forms of feedback, supporting the interactive activation hypothesis. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5891609','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5891609">Interaction in Spoken Word Recognition Models: Feedback Helps</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Magnuson, James S.; Mirman, Daniel; Luthra, Sahil; Strauss, Ted; Harris, Harlan D. 2018-01-01 Human perception, cognition, and action requires fast integration of bottom-up signals with top-down knowledge and context. A key theoretical perspective in cognitive science is the interactive activation hypothesis: forward and backward flow in bidirectionally connected neural networks allows humans and other biological systems to approximate optimal integration of bottom-up and top-down information under real-world constraints. An alternative view is that online feedback is neither necessary nor helpful; purely feed forward alternatives can be constructed for any feedback system, and online feedback could not improve processing and would preclude veridical perception. In the domain of spoken word recognition, the latter view was apparently supported by simulations using the interactive activation model, TRACE, with and without feedback: as many words were recognized more quickly without feedback as were recognized faster with feedback, However, these simulations used only a small set of words and did not address a primary motivation for interaction: making a model robust in noise. We conducted simulations using hundreds of words, and found that the majority were recognized more quickly with feedback than without. More importantly, as we added noise to inputs, accuracy and recognition times were better with feedback than without. We follow these simulations with a critical review of recent arguments that online feedback in interactive activation models like TRACE is distinct from other potentially helpful forms of feedback. We conclude that in addition to providing the benefits demonstrated in our simulations, online feedback provides a plausible means of implementing putatively distinct forms of feedback, supporting the interactive activation hypothesis. PMID:29666593 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19880045389&hterms=Unity&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DTitle%26N%3D0%26No%3D60%26Ntt%3DUnity','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19880045389&hterms=Unity&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DTitle%26N%3D0%26No%3D60%26Ntt%3DUnity">Stabilization and robustness of non-linear unity-feedback system - Factorization approach</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Desoer, C. A.; Kabuli, M. G. 1988-01-01 The paper is a self-contained discussion of a right factorization approach in the stability analysis of the nonlinear continuous-time or discrete-time, time-invariant or time-varying, well-posed unity-feedback system S1(P, C). It is shown that a well-posed stable feedback system S1(P, C) implies that P and C have right factorizations. In the case where C is stable, P has a normalized right-coprime factorization. The factorization approach is used in stabilization and simultaneous stabilization results. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23613585','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23613585">Assessment of radiative feedback in climate models using satellite observations of annual flux variation.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Tsushima, Yoko; Manabe, Syukuro 2013-05-07 In the climate system, two types of radiative feedback are in operation. The feedback of the first kind involves the radiative damping of the vertically uniform temperature perturbation of the troposphere and Earth's surface that approximately follows the Stefan-Boltzmann law of blackbody radiation. The second kind involves the change in the vertical lapse rate of temperature, water vapor, and clouds in the troposphere and albedo of the Earth's surface. Using satellite observations of the annual variation of the outgoing flux of longwave radiation and that of reflected solar radiation at the top of the atmosphere, this study estimates the so-called "gain factor," which characterizes the strength of radiative feedback of the second kind that operates on the annually varying, global-scale perturbation of temperature at the Earth's surface. The gain factor is computed not only for all sky but also for clear sky. The gain factor of so-called "cloud radiative forcing" is then computed as the difference between the two. The gain factors thus obtained are compared with those obtained from 35 models that were used for the fourth and fifth Intergovernmental Panel on Climate Change assessment. Here, we show that the gain factors obtained from satellite observations of cloud radiative forcing are effective for identifying systematic biases of the feedback processes that control the sensitivity of simulated climate, providing useful information for validating and improving a climate model. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29848372','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29848372">Mental models of audit and feedback in primary care settings.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Hysong, Sylvia J; Smitham, Kristen; SoRelle, Richard; Amspoker, Amber; Hughes, Ashley M; Haidet, Paul 2018-05-30 Audit and feedback has been shown to be instrumental in improving quality of care, particularly in outpatient settings. The mental model individuals and organizations hold regarding audit and feedback can moderate its effectiveness, yet this has received limited study in the quality improvement literature. In this study we sought to uncover patterns in mental models of current feedback practices within high- and low-performing healthcare facilities. We purposively sampled 16 geographically dispersed VA hospitals based on high and low performance on a set of chronic and preventive care measures. We interviewed up to 4 personnel from each location (n = 48) to determine the facility's receptivity to audit and feedback practices. Interview transcripts were analyzed via content and framework analysis to identify emergent themes. We found high variability in the mental models of audit and feedback, which we organized into positive and negative themes. We were unable to associate mental models of audit and feedback with clinical performance due to high variance in facility performance over time. Positive mental models exhibit perceived utility of audit and feedback practices in improving performance; whereas, negative mental models did not. Results speak to the variability of mental models of feedback, highlighting how facilities perceive current audit and feedback practices. Findings are consistent with prior research in that variability in feedback mental models is associated with lower performance.; Future research should seek to empirically link mental models revealed in this paper to high and low levels of clinical performance. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19990111731&hterms=hack&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dhack','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19990111731&hterms=hack&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dhack">Cloud Feedback in Atmospheric General Circulation Models: An Update</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Cess, R. D.; Zhang, M. H.; Ingram, W. J.; Potter, G. L.; Alekseev, V.; Barker, H. W.; Cohen-Solal, E.; Colman, R. A.; Dazlich, D. A.; DelGenio, A. D.; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_19990111731'); toggleEditAbsImage('author_19990111731_show'); toggleEditAbsImage('author_19990111731_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_19990111731_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_19990111731_hide"> 1996-01-01 Six years ago, we compared the climate sensitivity of 19 atmospheric general circulation models and found a roughly threefold variation among the models; most of this variation was attributed to differences in the models' depictions of cloud feedback. In an update of this comparison, current models showed considerably smaller differences in net cloud feedback, with most producing modest values. There are, however, substantial differences in the feedback components, indicating that the models still have physical disagreements. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27412170','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27412170">Model depicting aspects of audit and feedback that impact physicians' acceptance of clinical performance feedback.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Payne, Velma L; Hysong, Sylvia J 2016-07-13 Audit and feedback (A&F) is a strategy that has been used in various disciplines for performance and quality improvement. There is limited research regarding medical professionals' acceptance of clinical-performance feedback and whether feedback impacts clinical practice. The objectives of our research were to (1) investigate aspects of A&F that impact physicians' acceptance of performance feedback; (2) determine actions physicians take when receiving feedback; and (3) determine if feedback impacts physicians' patient-management behavior. In this qualitative study, we employed grounded theory methods to perform a secondary analysis of semi-structured interviews with 12 VA primary care physicians. We analyzed a subset of interview questions from the primary study, which aimed to determine how providers of high, low and moderately performing VA medical centers use performance feedback to maintain and improve quality of care, and determine perceived utility of performance feedback. Based on the themes emergent from our analysis and their observed relationships, we developed a model depicting aspects of the A&F process that impact feedback acceptance and physicians' patient-management behavior. The model is comprised of three core components - Reaction, Action and Impact - and depicts elements associated with feedback recipients' reaction to feedback, action taken when feedback is received, and physicians modifying their patient-management behavior. Feedback characteristics, the environment, external locus-of-control components, core values, emotion and the assessment process induce or deter reaction, action and impact. Feedback characteristics (content and timeliness), and the procedural justice of the assessment process (unjust penalties) impact feedback acceptance. External locus-of-control elements (financial incentives, competition), the environment (patient volume, time constraints) and emotion impact patient-management behavior. Receiving feedback generated </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li class="active">1</li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_2" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_1");'>1</a></li> <li class="active">2</li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="21"> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29677951','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29677951">Modelling Feedback in Virtual Patients: An Iterative Approach.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Stathakarou, Natalia; Kononowicz, Andrzej A; Henningsohn, Lars; McGrath, Cormac 2018-01-01 Virtual Patients (VPs) offer learners the opportunity to practice clinical reasoning skills and have recently been integrated in Massive Open Online Courses (MOOCs). Feedback is a central part of a branched VP, allowing the learner to reflect on the consequences of their decisions and actions. However, there is insufficient guidance on how to design feedback models within VPs and especially in the context of their application in MOOCs. In this paper, we share our experiences from building a feedback model for a bladder cancer VP in a Urology MOOC, following an iterative process in three steps. Our results demonstrate how we can systematize the process of improving the quality of VP components by the application of known literature frameworks and extend them with a feedback module. We illustrate the design and re-design process and exemplify with content from our VP. Our results can act as starting point for discussions on modelling feedback in VPs and invite future research on the topic. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ApJ...836..204N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ApJ...836..204N">Modeling for Stellar Feedback in Galaxy Formation Simulations</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Núñez, Alejandro; Ostriker, Jeremiah P.; Naab, Thorsten; Oser, Ludwig; Hu, Chia-Yu; Choi, Ena 2017-02-01 Various heuristic approaches to model unresolved supernova (SN) feedback in galaxy formation simulations exist to reproduce the formation of spiral galaxies and the overall inefficient conversion of gas into stars. Some models, however, require resolution-dependent scalings. We present a subresolution model representing the three major phases of supernova blast wave evolution—free expansion, energy-conserving Sedov-Taylor, and momentum-conserving snowplow—with energy scalings adopted from high-resolution interstellar-medium simulations in both uniform and multiphase media. We allow for the effects of significantly enhanced SN remnant propagation in a multiphase medium with the cooling radius scaling with the hot volume fraction, {f}{hot}, as {(1-{f}{hot})}-4/5. We also include winds from young massive stars and AGB stars, Strömgren sphere gas heating by massive stars, and a mechanism that limits gas cooling that is driven by radiative recombination of dense H II regions. We present initial tests for isolated Milky Way-like systems simulated with the Gadget-based code SPHgal with improved SPH prescription. Compared to pure thermal SN input, the model significantly suppresses star formation at early epochs, with star formation extended both in time and space in better accord with observations. Compared to models with pure thermal SN feedback, the age at which half the stellar mass is assembled increases by a factor of 2.4, and the mass-loading parameter and gas outflow rate from the galactic disk increase by a factor of 2. Simulation results are converged for a variation of two orders of magnitude in particle mass in the range (1.3-130) × 104 solar masses. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/EJ1013726.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/EJ1013726.pdf">Designing and Evaluating Tutoring Feedback Strategies for Digital Learning Environments on the Basis of the Interactive Tutoring Feedback Model</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Narciss, Susanne 2013-01-01 This paper describes the interactive tutoring feedback model (ITF-model; Narciss, 2006; 2008), and how it can be applied to the design and evaluation of feedback strategies for digital learning environments. The ITF-model conceptualizes formative tutoring feedback as a multidimensional instructional activity that aims at contributing to the… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=trails&id=EJ1172317','ERIC'); return false;" href="https://eric.ed.gov/?q=trails&id=EJ1172317">A Feedback Model for Data-Rich Learning Experiences</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Pardo, Abelardo 2018-01-01 Feedback has been identified as one of the factors with the largest potential for a positive impact in a learning experience. There is a significant body of knowledge studying feedback and providing guidelines for its implementation in learning environments. In parallel, the areas of learning analytics or educational data mining have emerged to… </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017MNRAS.472.1576F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017MNRAS.472.1576F">A minimalist feedback-regulated model for galaxy formation during the epoch of reionization</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Furlanetto, Steven R.; Mirocha, Jordan; Mebane, Richard H.; Sun, Guochao 2017-12-01 Near-infrared surveys have now determined the luminosity functions of galaxies at 6 ≲ z ≲ 8 to impressive precision and identified a number of candidates at even earlier times. Here, we develop a simple analytic model to describe these populations that allows physically motivated extrapolation to earlier times and fainter luminosities. We assume that galaxies grow through accretion on to dark matter haloes, which we model by matching haloes at fixed number density across redshift, and that stellar feedback limits the star formation rate. We allow for a variety of feedback mechanisms, including regulation through supernova energy and momentum from radiation pressure. We show that reasonable choices for the feedback parameters can fit the available galaxy data, which in turn substantially limits the range of plausible extrapolations of the luminosity function to earlier times and fainter luminosities: for example, the global star formation rate declines rapidly (by a factor of ∼20 from z = 6 to 15 in our fiducial model), but the bright galaxies accessible to observations decline even faster (by a factor ≳ 400 over the same range). Our framework helps us develop intuition for the range of expectations permitted by simple models of high-z galaxies that build on our understanding of 'normal' galaxy evolution. We also provide predictions for galaxy measurements by future facilities, including James Webb Space Telescope and Wide-Field Infrared Survey Telescope. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4204448','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4204448">Visual crowding illustrates the inadequacy of local vs. global and feedforward vs. feedback distinctions in modeling visual perception</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Clarke, Aaron M.; Herzog, Michael H.; Francis, Gregory 2014-01-01 Experimentalists tend to classify models of visual perception as being either local or global, and involving either feedforward or feedback processing. We argue that these distinctions are not as helpful as they might appear, and we illustrate these issues by analyzing models of visual crowding as an example. Recent studies have argued that crowding cannot be explained by purely local processing, but that instead, global factors such as perceptual grouping are crucial. Theories of perceptual grouping, in turn, often invoke feedback connections as a way to account for their global properties. We examined three types of crowding models that are representative of global processing models, and two of which employ feedback processing: a model based on Fourier filtering, a feedback neural network, and a specific feedback neural architecture that explicitly models perceptual grouping. Simulations demonstrate that crucial empirical findings are not accounted for by any of the models. We conclude that empirical investigations that reject a local or feedforward architecture offer almost no constraints for model construction, as there are an uncountable number of global and feedback systems. We propose that the identification of a system as being local or global and feedforward or feedback is less important than the identification of a system's computational details. Only the latter information can provide constraints on model development and promote quantitative explanations of complex phenomena. PMID:25374554 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29075847','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29075847">Robust permanence for ecological equations with internal and external feedbacks.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Patel, Swati; Schreiber, Sebastian J 2018-07-01 Species experience both internal feedbacks with endogenous factors such as trait evolution and external feedbacks with exogenous factors such as weather. These feedbacks can play an important role in determining whether populations persist or communities of species coexist. To provide a general mathematical framework for studying these effects, we develop a theorem for coexistence for ecological models accounting for internal and external feedbacks. Specifically, we use average Lyapunov functions and Morse decompositions to develop sufficient and necessary conditions for robust permanence, a form of coexistence robust to large perturbations of the population densities and small structural perturbations of the models. We illustrate how our results can be applied to verify permanence in non-autonomous models, structured population models, including those with frequency-dependent feedbacks, and models of eco-evolutionary dynamics. In these applications, we discuss how our results relate to previous results for models with particular types of feedbacks. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMGC53E0935K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMGC53E0935K">Temporal Arctic longwave surface emissivity feedbacks in the Community Earth System Model</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Kuo, C.; Feldman, D.; Huang, X.; Flanner, M.; Yang, P.; Chen, X. 2017-12-01 We have investigated how the inclusion of realistic and consistent surface emissivity in both land-surface and atmospheric components of the CESM coupled-climate model affects a wide range of climate variables. We did this by replacing the unit emissivity values in RRTMG_LW for water, fine-grained snow, and desert scenes with spectral emissivity values, and by replacing broadband emissivity values in surface components with the Planck-curve weighted counterparts. We find that this harmonized treatment of surface emissivity within CESM can be important for reducing high-latitude temperature biases. We also find that short-term effects of atmospheric dynamics and spectral information need to be considered to understand radiative effects in higher detail, and are possible with radiative kernels computed for every grid and time point for the entire model integration period. We find that conventional climatological feedback calculations indicate that sea-ice emissivity feedback is positive in sign, but that the radiative effects of the difference in emissivity between frozen and unfrozen surfaces exhibit seasonal dependence. Furthermore, this seasonality itself exhibits meridional asymmetry due to differences in sea-ice response to climate forcing between the Arctic and the Antarctic. In the Arctic, this seasonal, temporally higher order analysis exhibits increasing outgoing surface emissivity radiative response in a warming climate. While the sea-ice emissivity feedback and seasonal sea-ice emissivity radiative response amplitudes are a few percent of surface albedo feedbacks, the feedback analysis methods outlined in this work demonstrate that spatially and temporally localized feedback analysis can give insight into the mechanisms at work on those scales which differ in amplitude and sign from conventional climatological analyses. We note that the inclusion of this realistic physics leads to improved agreement between CESM model results and Arctic surface </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21468778','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21468778">Factors influencing responsiveness to feedback: on the interplay between fear, confidence, and reasoning processes.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Eva, Kevin W; Armson, Heather; Holmboe, Eric; Lockyer, Jocelyn; Loney, Elaine; Mann, Karen; Sargeant, Joan 2012-03-01 Self-appraisal has repeatedly been shown to be inadequate as a mechanism for performance improvement. This has placed greater emphasis on understanding the processes through which self-perception and external feedback interact to influence professional development. As feedback is inevitably interpreted through the lens of one's self-perceptions it is important to understand how learners interpret, accept, and use feedback (or not) and the factors that influence those interpretations. 134 participants from 8 health professional training/continuing competence programs were recruited to participate in focus groups. Analyses were designed to (a) elicit understandings of the processes used by learners and physicians to interpret, accept and use (or not) data to inform their perceptions of their clinical performance, and (b) further understand the factors (internal and external) believed to influence interpretation of feedback. Multiple influences appear to impact upon the interpretation and uptake of feedback. These include confidence, experience, and fear of not appearing knowledgeable. Importantly, however, each could have a paradoxical effect of both increasing and decreasing receptivity. Less prevalent but nonetheless important themes suggested mechanisms through which cognitive reasoning processes might impede growth from formative feedback. Many studies have examined the effectiveness of feedback through variable interventions focused on feedback delivery. This study suggests that it is equally important to consider feedback from the perspective of how it is received. The interplay observed between fear, confidence, and reasoning processes reinforces the notion that there is no simple recipe for the delivery of effective feedback. These factors should be taken into account when trying to understand (a) why self-appraisal can be flawed, (b) why appropriate external feedback is vital (yet can be ineffective), and (c) why we may need to disentangle the goals of </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26123726','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26123726">Targeted Feedback in the Milestones Era: Utilization of the Ask-Tell-Ask Feedback Model to Promote Reflection and Self-Assessment.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> French, Judith C; Colbert, Colleen Y; Pien, Lily C; Dannefer, Elaine F; Taylor, Christine A 2015-01-01 The Accreditation Council for Graduate Medical Education's Milestones Project focuses trainee education on the formation of valued behaviors and skills believed to be necessary for trainees to become independent practitioners. The development and refinement of behaviors and skills outlined within the milestones will require learners to monitor, reflect, and assess their own performance over time. External feedback provides an opportunity for learners to recalibrate their self-assessments, thereby enabling them to develop better self-monitoring and self-assessment skills. Yet, feedback to trainees is frequently generic, such as "great job," "nice work," or "you need to read more." In this article, we describe a feedback model that faculty can use to provide specific feedback, while increasing accountability for learners. We offer practical examples of its use in a variety of settings in the milestone era. The Ask-Tell-Ask (ATA) patient communication skills strategy, which was adapted for use as a trainee feedback model 10 years ago at our institution, is a learner-centered approach for reinforcing and modifying behaviors. The model is efficient, promotes learner accountability, and helps trainees develop reflection and self-assessment skills. A feedback agreement further enhances ATA by establishing a shared understanding of goals for the educational encounter. The ATA feedback model, combined with a feedback agreement, encourages learners to self-identify strengths and areas for improvement, before receiving feedback. Personal monitoring, reflection, self-assessment, and increased accountability make ATA an ideal learner-centered feedback model for the milestones era, which focuses on performance improvement over time. We believe the introduction of the ATA feedback model in surgical training programs is a step in the right direction towards meaningful programmatic culture change. Copyright © 2015 Association of Program Directors in Surgery. Published by Elsevier </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16354139','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16354139">A model for educational feedback based on clinical communication skills strategies: beyond the "feedback sandwich".</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Milan, Felise B; Parish, Sharon J; Reichgott, Michael J 2006-01-01 Feedback is an essential tool in medical education, and the process is often difficult for both faculty and learner. There are strong analogies between the provision of educational feedback and doctor-patient communication during the clinical encounter. Relationship-building skills used in the clinical setting-Partnership, Empathy, Apology, Respect, Legitimation, Support (PEARLS)-can establish trust with the learner to better manage difficult feedback situations involving personal issues, unprofessional behavior, or a defensive learner. Using the stage of readiness to change (transtheoretical) model, the educator can "diagnose" the learner's stage of readiness and employ focused interventions to encourage desired changes. This approach has been positively received by medical educators in faculty development workshops. A model for provision of educational feedback based on communication skills used in the clinical encounter can be useful in the medical education setting. More robust evaluation of the construct validity is required in actual training program situations. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/EJ806045.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/EJ806045.pdf">Feedback Model to Support Designers of Blended-Learning Courses</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Hummel, Hans G. K. 2006-01-01 Although extensive research has been carried out, describing the role of feedback in education, and many theoretical models are yet available, procedures and guidelines for actually designing and implementing feedback in practice have remained scarce so far. This explorative study presents a preliminary six-phase design model for feedback… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1438791-positive-tropical-marine-low-cloud-cover-feedback-inferred-from-cloud-controlling-factors','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1438791-positive-tropical-marine-low-cloud-cover-feedback-inferred-from-cloud-controlling-factors">Positive tropical marine low-cloud cover feedback inferred from cloud-controlling factors</a> <a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a> Qu, Xin; Hall, Alex; Klein, Stephen A.; ... 2015-09-28 Differences in simulations of tropical marine low-cloud cover (LCC) feedback are sources of significant spread in temperature responses of climate models to anthropogenic forcing. Here we show that in models the feedback is mainly driven by three large-scale changes—a strengthening tropical inversion, increasing surface latent heat flux, and an increasing vertical moisture gradient. Variations in the LCC response to these changes alone account for most of the spread in model-projected 21st century LCC changes. A methodology is devised to constrain the LCC response observationally using sea surface temperature (SST) as a surrogate for the latent heat flux and moisture gradient.more » In models where the current climate's LCC sensitivities to inversion strength and SST variations are consistent with observed, LCC decreases systematically, which would increase absorption of solar radiation. These results support a positive LCC feedback. Finally, correcting biases in the sensitivities will be an important step toward more credible simulation of cloud feedbacks.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=feedback+AND+business&pg=5&id=ED548606','ERIC'); return false;" href="https://eric.ed.gov/?q=feedback+AND+business&pg=5&id=ED548606">Factors Predicting Online Graduate Students' Responsiveness to Feedback from Their Professors</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Breslin, Mary R. 2012-01-01 College students act on their professors' feedback less often and less completely than their professors would like. The problem this study addressed is that the relative predictive value of factors concerning graduate students in online courses acting on their professors' feedback is unknown. By focusing on graduate students in… </li> <li> <a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840012515','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840012515">Algorithms for output feedback, multiple-model, and decentralized control problems</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Halyo, N.; Broussard, J. R. 1984-01-01 The optimal stochastic output feedback, multiple-model, and decentralized control problems with dynamic compensation are formulated and discussed. Algorithms for each problem are presented, and their relationship to a basic output feedback algorithm is discussed. An aircraft control design problem is posed as a combined decentralized, multiple-model, output feedback problem. A control design is obtained using the combined algorithm. An analysis of the design is presented. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22924469','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22924469">Modelling terrestrial nitrous oxide emissions and implications for climate feedback.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Xu-Ri; Prentice, I Colin; Spahni, Renato; Niu, Hai Shan 2012-10-01 Ecosystem nitrous oxide (N2O) emissions respond to changes in climate and CO2 concentration as well as anthropogenic nitrogen (N) enhancements. Here, we aimed to quantify the responses of natural ecosystem N2O emissions to multiple environmental drivers using a process-based global vegetation model (DyN-LPJ). We checked that modelled annual N2O emissions from nonagricultural ecosystems could reproduce field measurements worldwide, and experimentally observed responses to step changes in environmental factors. We then simulated global N2O emissions throughout the 20th century and analysed the effects of environmental changes. The model reproduced well the global pattern of N2O emissions and the observed responses of N cycle components to changes in environmental factors. Simulated 20th century global decadal-average soil emissions were c. 8.2-9.5 Tg N yr(-1) (or 8.3-10.3 Tg N yr(-1) with N deposition). Warming and N deposition contributed 0.85±0.41 and 0.80±0.14 Tg N yr(-1), respectively, to an overall upward trend. Rising CO2 also contributed, in part, through a positive interaction with warming. The modelled temperature dependence of N2O emission (c. 1 Tg N yr(-1) K(-1)) implies a positive climate feedback which, over the lifetime of N2O (114 yr), could become as important as the climate-carbon cycle feedback caused by soil CO2 release. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70032353','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70032353">Spatial pattern formation of coastal vegetation in response to external gradients and positive feedbacks affecting soil porewater salinity: A model study</a> <a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a> Jiang, J.; DeAngelis, D.L.; Smith, T. J.; Teh, S.Y.; Koh, H. L. 2012-01-01 Coastal vegetation of South Florida typically comprises salinity-tolerant mangroves bordering salinity-intolerant hardwood hammocks and fresh water marshes. Two primary ecological factors appear to influence the maintenance of mangrove/hammock ecotones against changes that might occur due to disturbances. One of these is a gradient in one or more environmental factors. The other is the action of positive feedback mechanisms, in which each vegetation community influences its local environment to favor itself, reinforcing the boundary between communities. The relative contributions of these two factors, however, can be hard to discern. A spatially explicit individual-based model of vegetation, coupled with a model of soil hydrology and salinity dynamics is presented here to simulate mangrove/hammock ecotones in the coastal margin habitats of South Florida. The model simulation results indicate that an environmental gradient of salinity, caused by tidal flux, is the key factor separating vegetation communities, while positive feedback involving the different interaction of each vegetation type with the vadose zone salinity increases the sharpness of boundaries, and maintains the ecological resilience of mangrove/hammock ecotones against small disturbances. Investigation of effects of precipitation on positive feedback indicates that the dry season, with its low precipitation, is the period of strongest positive feedback. ?? 2011 Springer Science+Business Media B.V. (outside the USA). </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29238118','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29238118">Mechanisms and Model Diversity of Trade-Wind Shallow Cumulus Cloud Feedbacks: A Review.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Vial, Jessica; Bony, Sandrine; Stevens, Bjorn; Vogel, Raphaela 2017-01-01 Shallow cumulus clouds in the trade-wind regions are at the heart of the long standing uncertainty in climate sensitivity estimates. In current climate models, cloud feedbacks are strongly influenced by cloud-base cloud amount in the trades. Therefore, understanding the key factors controlling cloudiness near cloud-base in shallow convective regimes has emerged as an important topic of investigation. We review physical understanding of these key controlling factors and discuss the value of the different approaches that have been developed so far, based on global and high-resolution model experimentations and process-oriented analyses across a range of models and for observations. The trade-wind cloud feedbacks appear to depend on two important aspects: (1) how cloudiness near cloud-base is controlled by the local interplay between turbulent, convective and radiative processes; (2) how these processes interact with their surrounding environment and are influenced by mesoscale organization. Our synthesis of studies that have explored these aspects suggests that the large diversity of model responses is related to fundamental differences in how the processes controlling trade cumulus operate in models, notably, whether they are parameterized or resolved. In models with parameterized convection, cloudiness near cloud-base is very sensitive to the vigor of convective mixing in response to changes in environmental conditions. This is in contrast with results from high-resolution models, which suggest that cloudiness near cloud-base is nearly invariant with warming and independent of large-scale environmental changes. Uncertainties are difficult to narrow using current observations, as the trade cumulus variability and its relation to large-scale environmental factors strongly depend on the time and/or spatial scales at which the mechanisms are evaluated. New opportunities for testing physical understanding of the factors controlling shallow cumulus cloud responses using </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017SGeo...38.1331V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017SGeo...38.1331V">Mechanisms and Model Diversity of Trade-Wind Shallow Cumulus Cloud Feedbacks: A Review</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Vial, Jessica; Bony, Sandrine; Stevens, Bjorn; Vogel, Raphaela 2017-11-01 Shallow cumulus clouds in the trade-wind regions are at the heart of the long standing uncertainty in climate sensitivity estimates. In current climate models, cloud feedbacks are strongly influenced by cloud-base cloud amount in the trades. Therefore, understanding the key factors controlling cloudiness near cloud-base in shallow convective regimes has emerged as an important topic of investigation. We review physical understanding of these key controlling factors and discuss the value of the different approaches that have been developed so far, based on global and high-resolution model experimentations and process-oriented analyses across a range of models and for observations. The trade-wind cloud feedbacks appear to depend on two important aspects: (1) how cloudiness near cloud-base is controlled by the local interplay between turbulent, convective and radiative processes; (2) how these processes interact with their surrounding environment and are influenced by mesoscale organization. Our synthesis of studies that have explored these aspects suggests that the large diversity of model responses is related to fundamental differences in how the processes controlling trade cumulus operate in models, notably, whether they are parameterized or resolved. In models with parameterized convection, cloudiness near cloud-base is very sensitive to the vigor of convective mixing in response to changes in environmental conditions. This is in contrast with results from high-resolution models, which suggest that cloudiness near cloud-base is nearly invariant with warming and independent of large-scale environmental changes. Uncertainties are difficult to narrow using current observations, as the trade cumulus variability and its relation to large-scale environmental factors strongly depend on the time and/or spatial scales at which the mechanisms are evaluated. New opportunities for testing physical understanding of the factors controlling shallow cumulus cloud responses using </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018scwv.book..159V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018scwv.book..159V">Mechanisms and Model Diversity of Trade-Wind Shallow Cumulus Cloud Feedbacks: A Review</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Vial, Jessica; Bony, Sandrine; Stevens, Bjorn; Vogel, Raphaela Shallow cumulus clouds in the trade-wind regions are at the heart of the long standing uncertainty in climate sensitivity estimates. In current climate models, cloud feedbacks are strongly influenced by cloud-base cloud amount in the trades. Therefore, understanding the key factors controlling cloudiness near cloud-base in shallow convective regimes has emerged as an important topic of investigation. We review physical understanding of these key controlling factors and discuss the value of the different approaches that have been developed so far, based on global and high-resolution model experimentations and process-oriented analyses across a range of models and for observations. The trade-wind cloud feedbacks appear to depend on two important aspects: (1) how cloudiness near cloud-base is controlled by the local interplay between turbulent, convective and radiative processes; (2) how these processes interact with their surrounding environment and are influenced by mesoscale organization. Our synthesis of studies that have explored these aspects suggests that the large diversity of model responses is related to fundamental differences in how the processes controlling trade cumulus operate in models, notably, whether they are parameterized or resolved. In models with parameterized convection, cloudiness near cloud-base is very sensitive to the vigor of convective mixing in response to changes in environmental conditions. This is in contrast with results from high-resolution models, which suggest that cloudiness near cloud-base is nearly invariant with warming and independent of large-scale environmental changes. Uncertainties are difficult to narrow using current observations, as the trade cumulus variability and its relation to large-scale environmental factors strongly depend on the time and/or spatial scales at which the mechanisms are evaluated. New opportunities for testing physical understanding of the factors controlling shallow cumulus cloud responses using </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_1");'>1</a></li> <li class="active">2</li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_3" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_1");'>1</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li class="active">3</li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="41"> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26438280','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26438280">Insights into low-latitude cloud feedbacks from high-resolution models.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Bretherton, Christopher S 2015-11-13 Cloud feedbacks are a leading source of uncertainty in the climate sensitivity simulated by global climate models (GCMs). Low-latitude boundary-layer and cumulus cloud regimes are particularly problematic, because they are sustained by tight interactions between clouds and unresolved turbulent circulations. Turbulence-resolving models better simulate such cloud regimes and support the GCM consensus that they contribute to positive global cloud feedbacks. Large-eddy simulations using sub-100 m grid spacings over small computational domains elucidate marine boundary-layer cloud response to greenhouse warming. Four observationally supported mechanisms contribute: 'thermodynamic' cloudiness reduction from warming of the atmosphere-ocean column, 'radiative' cloudiness reduction from CO2- and H2O-induced increase in atmospheric emissivity aloft, 'stability-induced' cloud increase from increased lower tropospheric stratification, and 'dynamical' cloudiness increase from reduced subsidence. The cloudiness reduction mechanisms typically dominate, giving positive shortwave cloud feedback. Cloud-resolving models with horizontal grid spacings of a few kilometres illuminate how cumulonimbus cloud systems affect climate feedbacks. Limited-area simulations and superparameterized GCMs show upward shift and slight reduction of cloud cover in a warmer climate, implying positive cloud feedbacks. A global cloud-resolving model suggests tropical cirrus increases in a warmer climate, producing positive longwave cloud feedback, but results are sensitive to subgrid turbulence and ice microphysics schemes. © 2015 The Author(s). </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1062399','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/1062399">Reduced-Order Model Based Feedback Control For Modified Hasegawa-Wakatani Model</a> <a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a> Goumiri, I. R.; Rowley, C. W.; Ma, Z. 2013-01-28 In this work, the development of model-based feedback control that stabilizes an unstable equilibrium is obtained for the Modi ed Hasegawa-Wakatani (MHW) equations, a classic model in plasma turbulence. First, a balanced truncation (a model reduction technique that has proven successful in ow control design problems) is applied to obtain a low dimensional model of the linearized MHW equation. Then a modelbased feedback controller is designed for the reduced order model using linear quadratic regulators (LQR). Finally, a linear quadratic gaussian (LQG) controller, which is more resistant to disturbances is deduced. The controller is applied on the non-reduced, nonlinear MHWmore » equations to stabilize the equilibrium and suppress the transition to drift-wave induced turbulence.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFM.A34A..08T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFM.A34A..08T">A Unified Approach to Quantifying Feedbacks in Earth System Models</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Taylor, K. E. 2008-12-01 In order to speed progress in reducing uncertainty in climate projections, the processes that most strongly influence those projections must be identified. It is of some importance, therefore, to assess the relative strengths of various climate feedbacks and to determine the degree to which various earth system models (ESMs) agree in their simulations of these processes. Climate feedbacks have been traditionally quantified in terms of their impact on the radiative balance of the planet, whereas carbon cycle responses have been assessed in terms of the size of the perturbations to the surface fluxes of carbon dioxide. In this study we introduce a diagnostic strategy for unifying the two approaches, which allows us to directly compare the strength of carbon-climate feedbacks with other conventional climate feedbacks associated with atmospheric and surface changes. Applying this strategy to a highly simplified model of the carbon-climate system demonstrates the viability of the approach. In the simple model we find that even if the strength of the carbon-climate feedbacks is very large, the uncertainty associated with the overall response of the climate system is likely to be dominated by uncertainties in the much larger feedbacks associated with clouds. This does not imply that the carbon cycle itself is unimportant, only that changes in the carbon cycle that are associated with climate change have a relatively small impact on global temperatures. This new, unified diagnostic approach is suitable for assessing feedbacks in even the most sophisticated earth system models. It will be interesting to see whether our preliminary conclusions are confirmed when output from the more realistic models is analyzed. This work was carried out at the University of California Lawrence Livermore National Laboratory under Contract W-7405-Eng-48. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22122870','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22122870">Feedback in web-based questionnaires as incentive to increase compliance in studies on lifestyle factors.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Bälter, Olle; Fondell, Elinor; Bälter, Katarina 2012-06-01 We explored the use of feedback in interactive web-based questionnaires for collecting data on lifestyle factors in epidemiological studies. Here we report from a cohort study on lifestyle factors and upper respiratory tract infections among 1805 men and women. We introduced interactivity in the form of personalized feedback and feedback on a group level regarding dietary intake, physical activity and incidence of infections in web-based questionnaires as incentives for the respondents to continue answering questions and stay in the study. The study was performed in Sweden. All participants were randomly selected from the population registry. Personalized feedback was offered in the baseline questionnaire and feedback on a group level in the five follow-up questionnaires. In total, 88 % of the participants actively chose to get personalized feedback at least once in the baseline questionnaire. The follow-up questionnaires were sent by email and the overall compliance at each follow-up was 83-84 %, despite only one reminder. In total, 74 % completed all five follow-ups. However, the compliance was higher among those who chose feedback in the baseline questionnaire compared with those who did not choose feedback. The results show that it is possible to use feedback in web questionnaires and that it has the potential to increase compliance. The majority of the participants actively chose to take part in the personalized feedback in the baseline questionnaire and future research should focus on improving the design of the feedback, which may ultimately result in even higher compliance in research studies. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMGC41B1087Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMGC41B1087Y">Vegetation-rainfall feedbacks across the Sahel: a combined observational and modeling study</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Yu, Y.; Notaro, M.; Wang, F.; Mao, J.; Shi, X.; Wei, Y. 2016-12-01 The Sahel rainfall is characterized by large interannual variability. Past modeling studies have concluded that the Sahel rainfall variability is primarily driven by oceanic forcings and amplified by land-atmosphere interactions. However, the relative importance of oceanic versus terrestrial drivers has never been assessed from observations. The current understanding of vegetation's impacts on climate, i.e. positive vegetation-rainfall feedback through the albedo, moisture, and momentum mechanisms, comes from untested models. Neither the positive vegetation-rainfall feedback, nor the underlying mechanisms, has been fully resolved in observations. The current study fills the knowledge gap about the observed vegetation-rainfall feedbacks, through the application of the multivariate statistical method Generalized Equilibrium Feedback Assessment (GEFA) to observational data. According to GEFA, the observed oceanic impacts dominate over terrestrial impacts on Sahel rainfall, except in the post-monsoon period. Positive leaf area index (LAI) anomalies favor an extended, wetter monsoon across the Sahel, largely due to moisture recycling. The albedo mechanism is not responsible for this positive vegetation feedback on the seasonal-interannual time scale, which is too short for a grass-desert transition. A low-level stabilization and subsidence is observed in response to increased LAI - potentially responsible for a negative vegetation-rainfall feedback. However, the positive moisture feedback overwhelms the negative momentum feedback, resulting in an observed positive vegetation-rainfall feedback. We further applied GEFA to a fully-coupled Community Earth System Model (CESM) control run, as an example of evaluating climate models against the GEFA-based observational benchmark. In contrast to the observed positive vegetation-rainfall feedbacks, CESM simulates a negative vegetation-rainfall feedback across Sahel, peaking in the pre-monsoon season. The simulated negative </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22130442-reduced-order-model-based-feedback-control-modified-hasegawa-wakatani-model','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22130442-reduced-order-model-based-feedback-control-modified-hasegawa-wakatani-model">Reduced-order model based feedback control of the modified Hasegawa-Wakatani model</a> <a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a> Goumiri, I. R.; Rowley, C. W.; Ma, Z. 2013-04-15 In this work, the development of model-based feedback control that stabilizes an unstable equilibrium is obtained for the Modified Hasegawa-Wakatani (MHW) equations, a classic model in plasma turbulence. First, a balanced truncation (a model reduction technique that has proven successful in flow control design problems) is applied to obtain a low dimensional model of the linearized MHW equation. Then, a model-based feedback controller is designed for the reduced order model using linear quadratic regulators. Finally, a linear quadratic Gaussian controller which is more resistant to disturbances is deduced. The controller is applied on the non-reduced, nonlinear MHW equations to stabilizemore » the equilibrium and suppress the transition to drift-wave induced turbulence.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19840051365&hterms=climate+exchange&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dclimate%2Bexchange','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19840051365&hterms=climate+exchange&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dclimate%2Bexchange">An energy balance climate model with cloud feedbacks</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Roads, J. O.; Vallis, G. K. 1984-01-01 The present two-level global climate model, which is based on the atmosphere-surface energy balance, includes physically based parameterizations for the exchange of heat and moisture across latitude belts and between the surface and the atmosphere, precipitation and cloud formation, and solar and IR radiation. The model field predictions obtained encompass surface and atmospheric temperature, precipitation, relative humidity, and cloudiness. In the model integrations presented, it is noted that cloudiness is generally constant with changing temperature at low latitudes. High altitude cloudiness increases with temperature, although the cloud feedback effect on the radiation field remains small because of compensating effects on thermal and solar radiation. The net global feedback by the cloud field is negative, but small. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3192965','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3192965">Positive Feedback Loops for Factor V and Factor VII Activation Supply Sensitivity to Local Surface Tissue Factor Density During Blood Coagulation</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Balandina, A.N.; Shibeko, A.M.; Kireev, D.A.; Novikova, A.A.; Shmirev, I.I.; Panteleev, M.A.; Ataullakhanov, F.I. 2011-01-01 Blood coagulation is triggered not only by surface tissue factor (TF) density but also by surface TF distribution. We investigated recognition of surface TF distribution patterns during blood coagulation and identified the underlying molecular mechanisms. For these investigations, we employed 1), an in vitro reaction-diffusion experimental model of coagulation; and 2), numerical simulations using a mathematical model of coagulation in a three-dimensional space. When TF was uniformly immobilized over the activating surface, the clotting initiation time in normal plasma increased from 4 min to >120 min, with a decrease in TF density from 100 to 0.7 pmol/m2. In contrast, surface-immobilized fibroblasts initiated clotting within 3–7 min, independently of fibroblast quantity and despite a change in average surface TF density from 0.5 to 130 pmol/m2. Experiments using factor V-, VII-, and VIII-deficient plasma and computer simulations demonstrated that different responses to these two TF distributions are caused by two positive feedback loops in the blood coagulation network: activation of the TF–VII complex by factor Xa, and activation of factor V by thrombin. This finding suggests a new role for these reactions: to supply sensitivity to local TF density during blood coagulation. PMID:22004734 </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015MNRAS.454.1958M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015MNRAS.454.1958M">An accurate halo model for fitting non-linear cosmological power spectra and baryonic feedback models</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Mead, A. J.; Peacock, J. A.; Heymans, C.; Joudaki, S.; Heavens, A. F. 2015-12-01 We present an optimized variant of the halo model, designed to produce accurate matter power spectra well into the non-linear regime for a wide range of cosmological models. To do this, we introduce physically motivated free parameters into the halo-model formalism and fit these to data from high-resolution N-body simulations. For a variety of Λ cold dark matter (ΛCDM) and wCDM models, the halo-model power is accurate to ≃ 5 per cent for k ≤ 10h Mpc-1 and z ≤ 2. An advantage of our new halo model is that it can be adapted to account for the effects of baryonic feedback on the power spectrum. We demonstrate this by fitting the halo model to power spectra from the OWLS (OverWhelmingly Large Simulations) hydrodynamical simulation suite via parameters that govern halo internal structure. We are able to fit all feedback models investigated at the 5 per cent level using only two free parameters, and we place limits on the range of these halo parameters for feedback models investigated by the OWLS simulations. Accurate predictions to high k are vital for weak-lensing surveys, and these halo parameters could be considered nuisance parameters to marginalize over in future analyses to mitigate uncertainty regarding the details of feedback. Finally, we investigate how lensing observables predicted by our model compare to those from simulations and from HALOFIT for a range of k-cuts and feedback models and quantify the angular scales at which these effects become important. Code to calculate power spectra from the model presented in this paper can be found at https://github.com/alexander-mead/hmcode. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=interactional+AND+quality&pg=7&id=EJ307812','ERIC'); return false;" href="https://eric.ed.gov/?q=interactional+AND+quality&pg=7&id=EJ307812">Classroom Factors Affecting Students: Self-Evaluation: An Interactional Model.</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Marshall, Hermine H.; Weinstein, Rhona S. 1984-01-01 A complex interactional model of classroom factors that contribute to the development of students' self-evaluations is presented. Factors described are: (1) task structure; (2) grouping practices; (3) feedback and evaluation procedures and information about ability; (4) motivational strategies; (5) locus of responsibility for learning; and (6) the… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19920031563&hterms=moderation&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dmoderation','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19920031563&hterms=moderation&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dmoderation">Interpretation of snow-climate feedback as produced by 17 general circulation models</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Cess, R. D.; Zhang, M.-H.; Potter, G. L.; Blanchet, J.-P.; Chalita, S.; Colman, R.; Dazlich, D. A.; Del Genio, A. D.; Lacis, A. A.; Dymnikov, V. 1991-01-01 Snow feedback is expected to amplify global warming caused by increasing concentrations of atmospheric greenhouse gases. The conventional explanation is that a warmer earth will have less snow cover, resulting in a darker planet that absorbs more solar radiation. An intercomparison of 17 general circulation models, for which perturbations of sea surface temperature were used as a surrogate climate change, suggests that this explanation is overly simplistic. The results instead indicate that additional amplification or moderation may be caused both by cloud interactions and longwave radiation. One measure of this net effect of snow feedback was found to differ markedly among the 17 climate models, ranging from weak negative feedback in some models to strong positive feedback in others. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20170001441&hterms=robin&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Drobin','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20170001441&hterms=robin&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Drobin">The Cloud Feedback Model Intercomparison Project (CFMIP) contribution to CMIP6.</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Webb, Mark J.; Andrews, Timothy; Bodas-Salcedo, Alejandro; Bony, Sandrine; Bretherton, Christopher S.; Chadwick, Robin; Chepfer, Helene; Douville, Herve; Good, Peter; Kay, Jennifer E.; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20170001441'); toggleEditAbsImage('author_20170001441_show'); toggleEditAbsImage('author_20170001441_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20170001441_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20170001441_hide"> 2017-01-01 The primary objective of CFMIP is to inform future assessments of cloud feedbacks through improved understanding of cloud-climate feedback mechanisms and better evaluation of cloud processes and cloud feedbacks in climate models. However, the CFMIP approach is also increasingly being used to understand other aspects of climate change, and so a second objective has now been introduced, to improve understanding of circulation, regional-scale precipitation, and non-linear changes. CFMIP is supporting ongoing model inter-comparison activities by coordinating a hierarchy of targeted experiments for CMIP6, along with a set of cloud-related output diagnostics. CFMIP contributes primarily to addressing the CMIP6 questions 'How does the Earth system respond to forcing?' and 'What are the origins and consequences of systematic model biases?' and supports the activities of the WCRP Grand Challenge on Clouds, Circulation and Climate Sensitivity. A compact set of Tier 1 experiments is proposed for CMIP6 to address this question: (1) what are the physical mechanisms underlying the range of cloud feedbacks and cloud adjustments predicted by climate models, and which models have the most credible cloud feedbacks? Additional Tier 2 experiments are proposed to address the following questions. (2) Are cloud feedbacks consistent for climate cooling and warming, and if not, why? (3) How do cloud-radiative effects impact the structure, the strength and the variability of the general atmospheric circulation in present and future climates? (4) How do responses in the climate system due to changes in solar forcing differ from changes due to CO2, and is the response sensitive to the sign of the forcing? (5) To what extent is regional climate change per CO2 doubling state-dependent (non-linear), and why? (6) Are climate feedbacks during the 20th century different to those acting on long-term climate change and climate sensitivity? (7) How do regional climate responses (e.g. in precipitation </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22895867','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22895867">Knowing and acting in the clinical workplace: trainees' perspectives on modelling and feedback.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Stegeman, J H; Schoten, E J; Terpstra, O T 2013-10-01 In this article we discuss clinical workplace learning using a dual approach: a theoretical one and an empirical one. Drawing on the philosophical work of Aristotle, Polanyi and Schön we posit that the 'knowing and acting' underpinning day-to-day medical practice is personal and embraces by nature a tacit dimension. Consequently, imparting and acquiring this knowledge type necessitates personal interaction between trainer and trainee. The tacit dimension particularly influences modelling and feedback. In our empirical exploration we explore these educational routes in two disparate disciplines: surgery and paediatrics. We use a longitudinal design with in-depth interviewing. Our conclusion on modelling is: modelling is a dynamic and fragmented process reflecting discipline bound characteristics and working styles. On feedback it is: 'feedback' serves as vehicle for three distinctive forms of commenting on performance, each holding a specific power of expression for learning. We propose to view clinical workplace learning as: an interactive master-apprenticeship model encompassing modelling and feedback as natural educational routes. We conceptualise modelling and feedback as 'function' of interaction (developing grounded theory). Modelling function and feedback function may serve to study these routes as didactical components of ongoing interaction between trainer and trainee rather than an educator-driven series of unrelated events. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=cycling&pg=2&id=EJ870692','ERIC'); return false;" href="https://eric.ed.gov/?q=cycling&pg=2&id=EJ870692">Finite Feedback Cycling in Structural Equation Models</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Hayduk, Leslie A. 2009-01-01 In models containing reciprocal effects, or longer causal loops, the usual effect estimates assume that any effect touching a loop initiates an infinite cycling of effects around that loop. The real world, in contrast, might permit only finite feedback cycles. I use a simple hypothetical model to demonstrate that if the world permits only a few… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4043157','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4043157">Ribosome flow model with positive feedback</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Margaliot, Michael; Tuller, Tamir 2013-01-01 Eukaryotic mRNAs usually form a circular structure; thus, ribosomes that terminatae translation at the 3′ end can diffuse with increased probability to the 5′ end of the transcript, initiating another cycle of translation. This phenomenon describes ribosomal flow with positive feedback—an increase in the flow of ribosomes terminating translating the open reading frame increases the ribosomal initiation rate. The aim of this paper is to model and rigorously analyse translation with feedback. We suggest a modified version of the ribosome flow model, called the ribosome flow model with input and output. In this model, the input is the initiation rate and the output is the translation rate. We analyse this model after closing the loop with a positive linear feedback. We show that the closed-loop system admits a unique globally asymptotically stable equilibrium point. From a biophysical point of view, this means that there exists a unique steady state of ribosome distributions along the mRNA, and thus a unique steady-state translation rate. The solution from any initial distribution will converge to this steady state. The steady-state distribution demonstrates a decrease in ribosome density along the coding sequence. For the case of constant elongation rates, we obtain expressions relating the model parameters to the equilibrium point. These results may perhaps be used to re-engineer the biological system in order to obtain a desired translation rate. PMID:23720534 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4072518','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4072518">Mechanistic, Mathematical Model to Predict the Dynamics of Tissue Genesis in Bone Defects via Mechanical Feedback and Mediation of Biochemical Factors</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Moore, Shannon R.; Saidel, Gerald M.; Knothe, Ulf; Knothe Tate, Melissa L. 2014-01-01 The link between mechanics and biology in the generation and the adaptation of bone has been well studied in context of skeletal development and fracture healing. Yet, the prediction of tissue genesis within - and the spatiotemporal healing of - postnatal defects, necessitates a quantitative evaluation of mechano-biological interactions using experimental and clinical parameters. To address this current gap in knowledge, this study aims to develop a mechanistic mathematical model of tissue genesis using bone morphogenetic protein (BMP) to represent of a class of factors that may coordinate bone healing. Specifically, we developed a mechanistic, mathematical model to predict the dynamics of tissue genesis by periosteal progenitor cells within a long bone defect surrounded by periosteum and stabilized via an intramedullary nail. The emergent material properties and mechanical environment associated with nascent tissue genesis influence the strain stimulus sensed by progenitor cells within the periosteum. Using a mechanical finite element model, periosteal surface strains are predicted as a function of emergent, nascent tissue properties. Strains are then input to a mechanistic mathematical model, where mechanical regulation of BMP-2 production mediates rates of cellular proliferation, differentiation and tissue production, to predict healing outcomes. A parametric approach enables the spatial and temporal prediction of endochondral tissue regeneration, assessed as areas of cartilage and mineralized bone, as functions of radial distance from the periosteum and time. Comparing model results to histological outcomes from two previous studies of periosteum-mediated bone regeneration in a common ovine model, it was shown that mechanistic models incorporating mechanical feedback successfully predict patterns (spatial) and trends (temporal) of bone tissue regeneration. The novel model framework presented here integrates a mechanistic feedback system based on the </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1395318-cloud-feedback-model-intercomparison-project-cfmip-contribution-cmip6','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1395318-cloud-feedback-model-intercomparison-project-cfmip-contribution-cmip6">The Cloud Feedback Model Intercomparison Project (CFMIP) contribution to CMIP6</a> <a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a> Webb, Mark J.; Andrews, Timothy; Bodas-Salcedo, Alejandro; ... 2017-01-01 Our primary objective of CFMIP is to inform future assessments of cloud feedbacks through improved understanding of cloud–climate feedback mechanisms and better evaluation of cloud processes and cloud feedbacks in climate models. But, the CFMIP approach is also increasingly being used to understand other aspects of climate change, and so a second objective has now been introduced, to improve understanding of circulation, regional-scale precipitation, and non-linear changes. CFMIP is supporting ongoing model inter-comparison activities by coordinating a hierarchy of targeted experiments for CMIP6, along with a set of cloud-related output diagnostics. CFMIP contributes primarily to addressing the CMIP6 questions Howmore » does the Earth system respond to forcing? and What are the origins and consequences of systematic model biases? and supports the activities of the WCRP Grand Challenge on Clouds, Circulation and Climate Sensitivity.A compact set of Tier 1 experiments is proposed for CMIP6 to address this question: (1) what are the physical mechanisms underlying the range of cloud feedbacks and cloud adjustments predicted by climate models, and which models have the most credible cloud feedbacks? Additional Tier 2 experiments are proposed to address the following questions. (2) Are cloud feedbacks consistent for climate cooling and warming, and if not, why? (3) How do cloud-radiative effects impact the structure, the strength and the variability of the general atmospheric circulation in present and future climates? (4) How do responses in the climate system due to changes in solar forcing differ from changes due to CO 2, and is the response sensitive to the sign of the forcing? (5) To what extent is regional climate change per CO 2 doubling state-dependent (non-linear), and why? (6) Are climate feedbacks during the 20th century different to those acting on long-term climate change and climate sensitivity? (7) How do regional climate responses (e.g. in </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1395318','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/1395318">The Cloud Feedback Model Intercomparison Project (CFMIP) contribution to CMIP6</a> <a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a> Webb, Mark J.; Andrews, Timothy; Bodas-Salcedo, Alejandro Our primary objective of CFMIP is to inform future assessments of cloud feedbacks through improved understanding of cloud–climate feedback mechanisms and better evaluation of cloud processes and cloud feedbacks in climate models. But, the CFMIP approach is also increasingly being used to understand other aspects of climate change, and so a second objective has now been introduced, to improve understanding of circulation, regional-scale precipitation, and non-linear changes. CFMIP is supporting ongoing model inter-comparison activities by coordinating a hierarchy of targeted experiments for CMIP6, along with a set of cloud-related output diagnostics. CFMIP contributes primarily to addressing the CMIP6 questions Howmore » does the Earth system respond to forcing? and What are the origins and consequences of systematic model biases? and supports the activities of the WCRP Grand Challenge on Clouds, Circulation and Climate Sensitivity.A compact set of Tier 1 experiments is proposed for CMIP6 to address this question: (1) what are the physical mechanisms underlying the range of cloud feedbacks and cloud adjustments predicted by climate models, and which models have the most credible cloud feedbacks? Additional Tier 2 experiments are proposed to address the following questions. (2) Are cloud feedbacks consistent for climate cooling and warming, and if not, why? (3) How do cloud-radiative effects impact the structure, the strength and the variability of the general atmospheric circulation in present and future climates? (4) How do responses in the climate system due to changes in solar forcing differ from changes due to CO 2, and is the response sensitive to the sign of the forcing? (5) To what extent is regional climate change per CO 2 doubling state-dependent (non-linear), and why? (6) Are climate feedbacks during the 20th century different to those acting on long-term climate change and climate sensitivity? (7) How do regional climate responses (e.g. in </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21166326','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21166326">An integrative model linking feedback environment and organizational citizenship behavior.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Peng, Jei-Chen; Chiu, Su-Fen 2010-01-01 Past empirical evidence has suggested that a positive supervisor feedback environment may enhance employees' organizational citizenship behavior (OCB). In this study, we aim to extend previous research by proposing and testing an integrative model that examines the mediating processes underlying the relationship between supervisor feedback environment and employee OCB. Data were collected from 259 subordinate-supervisor dyads across a variety of organizations in Taiwan. We used structural equation modeling to test our hypotheses. The results demonstrated that supervisor feedback environment influenced employees' OCB indirectly through (1) both positive affective-cognition and positive attitude (i.e., person-organization fit and organizational commitment), and (2) both negative affective-cognition and negative attitude (i.e., role stressors and job burnout). Theoretical and practical implications are discussed. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27920978','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27920978">Network interactions underlying mirror feedback in stroke: A dynamic causal modeling study.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Saleh, Soha; Yarossi, Mathew; Manuweera, Thushini; Adamovich, Sergei; Tunik, Eugene 2017-01-01 Mirror visual feedback (MVF) is potentially a powerful tool to facilitate recovery of disordered movement and stimulate activation of under-active brain areas due to stroke. The neural mechanisms underlying MVF have therefore been a focus of recent inquiry. Although it is known that sensorimotor areas can be activated via mirror feedback, the network interactions driving this effect remain unknown. The aim of the current study was to fill this gap by using dynamic causal modeling to test the interactions between regions in the frontal and parietal lobes that may be important for modulating the activation of the ipsilesional motor cortex during mirror visual feedback of unaffected hand movement in stroke patients. Our intent was to distinguish between two theoretical neural mechanisms that might mediate ipsilateral activation in response to mirror-feedback: transfer of information between bilateral motor cortices versus recruitment of regions comprising an action observation network which in turn modulate the motor cortex. In an event-related fMRI design, fourteen chronic stroke subjects performed goal-directed finger flexion movements with their unaffected hand while observing real-time visual feedback of the corresponding (veridical) or opposite (mirror) hand in virtual reality. Among 30 plausible network models that were tested, the winning model revealed significant mirror feedback-based modulation of the ipsilesional motor cortex arising from the contralesional parietal cortex, in a region along the rostral extent of the intraparietal sulcus. No winning model was identified for the veridical feedback condition. We discuss our findings in the context of supporting the latter hypothesis, that mirror feedback-based activation of motor cortex may be attributed to engagement of a contralateral (contralesional) action observation network. These findings may have important implications for identifying putative cortical areas, which may be targeted with non </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_1");'>1</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li class="active">3</li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_4" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li class="active">4</li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="61"> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017GMD....10..359W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017GMD....10..359W">The Cloud Feedback Model Intercomparison Project (CFMIP) contribution to CMIP6</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Webb, Mark J.; Andrews, Timothy; Bodas-Salcedo, Alejandro; Bony, Sandrine; Bretherton, Christopher S.; Chadwick, Robin; Chepfer, Hélène; Douville, Hervé; Good, Peter; Kay, Jennifer E.; Klein, Stephen A.; Marchand, Roger; Medeiros, Brian; Pier Siebesma, A.; Skinner, Christopher B.; Stevens, Bjorn; Tselioudis, George; Tsushima, Yoko; Watanabe, Masahiro 2017-01-01 The primary objective of CFMIP is to inform future assessments of cloud feedbacks through improved understanding of cloud-climate feedback mechanisms and better evaluation of cloud processes and cloud feedbacks in climate models. However, the CFMIP approach is also increasingly being used to understand other aspects of climate change, and so a second objective has now been introduced, to improve understanding of circulation, regional-scale precipitation, and non-linear changes. CFMIP is supporting ongoing model inter-comparison activities by coordinating a hierarchy of targeted experiments for CMIP6, along with a set of cloud-related output diagnostics. CFMIP contributes primarily to addressing the CMIP6 questions <q>How does the Earth system respond to forcing?</q> and <q>What are the origins and consequences of systematic model biases?</q> and supports the activities of the WCRP Grand Challenge on Clouds, Circulation and Climate Sensitivity.A compact set of Tier 1 experiments is proposed for CMIP6 to address this question: (1) what are the physical mechanisms underlying the range of cloud feedbacks and cloud adjustments predicted by climate models, and which models have the most credible cloud feedbacks? Additional Tier 2 experiments are proposed to address the following questions. (2) Are cloud feedbacks consistent for climate cooling and warming, and if not, why? (3) How do cloud-radiative effects impact the structure, the strength and the variability of the general atmospheric circulation in present and future climates? (4) How do responses in the climate system due to changes in solar forcing differ from changes due to CO2, and is the response sensitive to the sign of the forcing? (5) To what extent is regional climate change per CO2 doubling state-dependent (non-linear), and why? (6) Are climate feedbacks during the 20th century different to those acting on long-term climate change and climate sensitivity? (7) How do regional climate responses (e.g. in </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRD..123..789K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRD..123..789K">Time-Dependent Cryospheric Longwave Surface Emissivity Feedback in the Community Earth System Model</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Kuo, Chaincy; Feldman, Daniel R.; Huang, Xianglei; Flanner, Mark; Yang, Ping; Chen, Xiuhong 2018-01-01 Frozen and unfrozen surfaces exhibit different longwave surface emissivities with different spectral characteristics, and outgoing longwave radiation and cooling rates are reduced for unfrozen scenes relative to frozen ones. Here physically realistic modeling of spectrally resolved surface emissivity throughout the coupled model components of the Community Earth System Model (CESM) is advanced, and implications for model high-latitude biases and feedbacks are evaluated. It is shown that despite a surface emissivity feedback amplitude that is, at most, a few percent of the surface albedo feedback amplitude, the inclusion of realistic, harmonized longwave, spectrally resolved emissivity information in CESM1.2.2 reduces wintertime Arctic surface temperature biases from -7.2 ± 0.9 K to -1.1 ± 1.2 K, relative to observations. The bias reduction is most pronounced in the Arctic Ocean, a region for which Coupled Model Intercomparison Project version 5 (CMIP5) models exhibit the largest mean wintertime cold bias, suggesting that persistent polar temperature biases can be lessened by including this physically based process across model components. The ice emissivity feedback of CESM1.2.2 is evaluated under a warming scenario with a kernel-based approach, and it is found that emissivity radiative kernels exhibit water vapor and cloud cover dependence, thereby varying spatially and decreasing in magnitude over the course of the scenario from secular changes in atmospheric thermodynamics and cloud patterns. Accounting for the temporally varying radiative responses can yield diagnosed feedbacks that differ in sign from those obtained from conventional climatological feedback analysis methods. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.1020H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.1020H">The biological carbon pump in the ocean: Reviewing model representations and its feedbacks on climate perturbations.</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Hülse, Dominik; Arndt, Sandra; Ridgwell, Andy; Wilson, Jamie 2016-04-01 The ocean-sediment system, as the biggest carbon reservoir in the Earth's carbon cycle, plays a crucial role in regulating atmospheric carbon dioxide concentrations and climate. Therefore, it is essential to constrain the importance of marine carbon cycle feedbacks on global warming and ocean acidification. Arguably, the most important single component of the ocean's carbon cycle is the so-called "biological carbon pump". It transports carbon that is fixed in the light-flooded surface layer of the ocean to the deep ocean and the surface sediment, where it is degraded/dissolved or finally buried in the deep sediments. Over the past decade, progress has been made in understanding different factors that control the efficiency of the biological carbon pump and their feedbacks on the global carbon cycle and climate (i.e. ballasting = ocean acidification feedback; temperature dependant organic matter degradation = global warming feedback; organic matter sulphurisation = anoxia/euxinia feedback). Nevertheless, many uncertainties concerning the interplay of these processes and/or their relative significance remain. In addition, current Earth System Models tend to employ empirical and static parameterisations of the biological pump. As these parametric representations are derived from a limited set of present-day observations, their ability to represent carbon cycle feedbacks under changing climate conditions is limited. The aim of my research is to combine past carbon cycling information with a spatially resolved global biogeochemical model to constrain the functioning of the biological pump and to base its mathematical representation on a more mechanistic approach. Here, I will discuss important aspects that control the efficiency of the ocean's biological carbon pump, review how these processes of first order importance are mathematically represented in existing Earth system Models of Intermediate Complexity (EMIC) and distinguish different approaches to approximate </li> <li> <a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19900065039&hterms=consequences+climate+change&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dconsequences%2Bclimate%2Bchange','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19900065039&hterms=consequences+climate+change&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dconsequences%2Bclimate%2Bchange">Intercomparison and interpretation of climate feedback processes in 19 atmospheric general circulation models</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Cess, R. D.; Potter, G. L.; Blanchet, J. P.; Boer, G. J.; Del Genio, A. D. 1990-01-01 The present study provides an intercomparison and interpretation of climate feedback processes in 19 atmospheric general circulation models. This intercomparison uses sea surface temperature change as a surrogate for climate change. The interpretation of cloud-climate interactions is given special attention. A roughly threefold variation in one measure of global climate sensitivity is found among the 19 models. The important conclusion is that most of this variation is attributable to differences in the models' depiction of cloud feedback, a result that emphasizes the need for improvements in the treatment of clouds in these models if they are ultimately to be used as reliable climate predictors. It is further emphazied that cloud feedback is the consequence of all interacting physical and dynamical processes in a general circulation model. The result of these processes is to produce changes in temperature, moisture distribution, and clouds which are integrated into the radiative response termed cloud feedback. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22492409-measurements-linewidth-enhancement-factor-mid-infrared-quantum-cascade-lasers-different-optical-feedback-techniques','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22492409-measurements-linewidth-enhancement-factor-mid-infrared-quantum-cascade-lasers-different-optical-feedback-techniques">Measurements of the linewidth enhancement factor of mid-infrared quantum cascade lasers by different optical feedback techniques</a> <a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a> Jumpertz, L., E-mail: louise.jumpertz@telecom-paristech.fr; MirSense, 8 avenue de la Vauve, F-91120 Palaiseau; Michel, F. 2016-01-15 Precise knowledge of the linewidth enhancement factor of a semiconductor laser under actual operating conditions is of prime importance since this parameter dictates various phenomena such as linewidth broadening or optical nonlinearities enhancement. The above-threshold linewidth enhancement factor of a mid-infrared quantum cascade laser structure operated at 10{sup ∘}C is determined experimentally using two different methods based on optical feedback. Both Fabry-Perot and distributed feedback quantum cascade lasers based on the same active area design are studied, the former by following the wavelength shift as a function of the feedback strength and the latter by self-mixing interferometry. The results aremore » consistent and unveil a clear pump current dependence of the linewidth enhancement factor, with values ranging from 0.8 to about 3.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED579292.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED579292.pdf">Collaborative Peer Feedback</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Smith, David A. 2017-01-01 Feedback on assessed work is invaluable to student learning, but there is a limit to the amount of feedback an instructor may provide. Peer feedback increases the volume of feedback possible, but potentially reduces the quality of the feedback. This research proposes a model of collaborative peer feedback designed to increase quality of peer… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27607659','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27607659">Model for a pulsed terahertz quantum cascade laser under optical feedback.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Agnew, Gary; Grier, Andrew; Taimre, Thomas; Lim, Yah Leng; Bertling, Karl; Ikonić, Zoran; Valavanis, Alexander; Dean, Paul; Cooper, Jonathan; Khanna, Suraj P; Lachab, Mohammad; Linfield, Edmund H; Davies, A Giles; Harrison, Paul; Indjin, Dragan; Rakić, Aleksandar D 2016-09-05 Optical feedback effects in lasers may be useful or problematic, depending on the type of application. When semiconductor lasers are operated using pulsed-mode excitation, their behavior under optical feedback depends on the electronic and thermal characteristics of the laser, as well as the nature of the external cavity. Predicting the behavior of a laser under both optical feedback and pulsed operation therefore requires a detailed model that includes laser-specific thermal and electronic characteristics. In this paper we introduce such a model for an exemplar bound-to-continuum terahertz frequency quantum cascade laser (QCL), illustrating its use in a selection of pulsed operation scenarios. Our results demonstrate significant interplay between electro-optical, thermal, and feedback phenomena, and that this interplay is key to understanding QCL behavior in pulsed applications. Further, our results suggest that for many types of QCL in interferometric applications, thermal modulation via low duty cycle pulsed operation would be an alternative to commonly used adiabatic modulation. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29240456','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29240456">Trainees' Perceptions of Feedback: Validity Evidence for Two FEEDME (Feedback in Medical Education) Instruments.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Bing-You, Robert; Ramesh, Saradha; Hayes, Victoria; Varaklis, Kalli; Ward, Denham; Blanco, Maria 2018-01-01 Construct: Medical educators consider feedback a core component of the educational process. Effective feedback allows learners to acquire new skills, knowledge, and attitudes. Learners' perceptions of feedback are an important aspect to assess with valid methods in order to improve the feedback skills of educators and the feedback culture. Although guidelines for delivering effective feedback have existed for several decades, medical students and residents often indicate that they receive little feedback. A recent scoping review on feedback in medical education did not reveal any validity evidence on instruments to assess learner's perceptions of feedback. The purpose of our study was to gather validity evidence on two novel FEEDME (Feedback in Medical Education) instruments to assess medical students' and residents' perceptions of the feedback that they receive. After the authors developed an initial instrument with 54 items, cognitive interviews with medical students and residents suggested that 2 separate instruments were needed, one focused on the feedback culture (FEEDME-Culture) and the other on the provider of feedback (FEEDME-Provider). A Delphi study with 17 medical education experts and faculty members assessed content validity. The response process was explored involving 31 medical students and residents at 2 academic institutions. Exploratory factor analysis and reliability analyses were performed on completed instruments. Two Delphi consultation rounds refined the wording of items and eliminated several items. Learners found both instruments easy and quick to answer; it took them less than 5 minutes to complete. Learners preferred an electronic format of the instruments over paper. Factor analysis revealed a two- and three-factor solution for the FEEDME-Culture and FEEDME-Provider instruments, respectively. Cronbach's alpha was greater than 0.80 for all factors. Items on both instruments were moderately to highly correlated (range, r = .3-.7). Our </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JGRA..117.2308D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JGRA..117.2308D">The relativistic feedback discharge model of terrestrial gamma ray flashes</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Dwyer, Joseph R. 2012-02-01 As thunderclouds charge, the large-scale fields may approach the relativistic feedback threshold, above which the production of relativistic runaway electron avalanches becomes self-sustaining through the generation of backward propagating runaway positrons and backscattered X-rays. Positive intracloud (IC) lightning may force the large-scale electric fields inside thunderclouds above the relativistic feedback threshold, causing the number of runaway electrons, and the resulting X-ray and gamma ray emission, to grow exponentially, producing very large fluxes of energetic radiation. As the flux of runaway electrons increases, ionization eventually causes the electric field to discharge, bringing the field below the relativistic feedback threshold again and reducing the flux of runaway electrons. These processes are investigated with a new model that includes the production, propagation, diffusion, and avalanche multiplication of runaway electrons; the production and propagation of X-rays and gamma rays; and the production, propagation, and annihilation of runaway positrons. In this model, referred to as the relativistic feedback discharge model, the large-scale electric fields are calculated self-consistently from the charge motion of the drifting low-energy electrons and ions, produced from the ionization of air by the runaway electrons, including two- and three-body attachment and recombination. Simulation results show that when relativistic feedback is considered, bright gamma ray flashes are a natural consequence of upward +IC lightning propagating in large-scale thundercloud fields. Furthermore, these flashes have the same time structures, including both single and multiple pulses, intensities, angular distributions, current moments, and energy spectra as terrestrial gamma ray flashes, and produce large current moments that should be observable in radio waves. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016cxo..prop.4839D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016cxo..prop.4839D">Testing Precipitation-Driven Feedback Models in Nearby Ellipticals</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Donahue, Megan 2016-09-01 We propose to analyze the inner cooling-time and entropy profiles of 12 elliptical galaxies with strong radio AGN. X-ray studies of galaxy-cluster cores and massive ellipticals indicate that feedback from an AGN replaces energy radiated by these objects. The AGN at 10 pc seems tuned to the thermodynamic state of gas on 10 kpc scales, but how that occurs is a resilient mystery. The precipitation model posits if the AGN does not provide enough heat, then thermal instabilities rain cold clouds on it, increasing accretion from Bondi to 100 times that rate when t_cool drops below 10 t_ff. We will test precipitation-driven feedback models by measuring t_cool and gravitational potential within the central kpc and to see how radio power is related to t_c/t_ff at small radii in these galaxies. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013APS..DPPTI2003H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013APS..DPPTI2003H">Feedback-Assisted Extension of the Tokamak Operating Space to Low Safety Factor</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Hanson, J. M. 2013-10-01 Recent DIII-D experiments have demonstrated stable operation at very low edge safety factor, q95 <~ 2 through the use of magnetic feedback to control the n = 1 resistive wall mode (RWM) instability. The performance of tokamak fusion devices may benefit from increased plasma current, and thus, decreased q. However, disruptive stability limits are commonly encountered in experiments at qedge ~ 2 (limited plasmas) and q95 ~ 2 (diverted plasmas), limiting exploration of low q regimes. In the recent DIII-D experiments, the impact and control of key disruptive instabilities was studied. Locked n = 1 modes with exponential growth times on the order of the wall eddy current decay timescale τw preceded disruptions at q95 = 2 . The instabilities have a poloidal structure that is consistent with VALEN simulations of the RWM mode structure at q95 = 2 . Applying proportional gain magnetic feedback control of the n = 1 mode resulted in stabilized operation with q95 reaching 1.9, and an extension of the discharge lifetime for > 100τw . Loss of feedback control was accompanied by power supply saturation, followed by a rapidly growing n = 1 mode and disruption. Comparisons of the feedback dynamics with VALEN simulations will be presented. The DIII-D results complement and will be discussed alongside recent RFX-MOD demonstrations of RWM control using magnetic feedback in limited tokamak discharges with qedge < 2. These results call attention to the utility of magnetic feedback in significantly extending the tokamak operational space and potentially opening a new route to economical fusion power production. Supported by the US Department of Energy under DE-FG02-04ER54761 and DE-FC02-04ER54698. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20040088956&hterms=heart&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dheart','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20040088956&hterms=heart&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dheart">Modeling heart rate variability by stochastic feedback</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Amaral, L. A.; Goldberger, A. L.; Stanley, H. E. 1999-01-01 We consider the question of how the cardiac rhythm spontaneously self-regulates and propose a new mechanism as a possible answer. We model the neuroautonomic regulation of the heart rate as a stochastic feedback system and find that the model successfully accounts for key characteristics of cardiac variability, including the 1/f power spectrum, the functional form and scaling of the distribution of variations of the interbeat intervals, and the correlations in the Fourier phases which indicate nonlinear dynamics. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5383005','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5383005">Evaluation of stiffness feedback for hard nodule identification on a phantom silicone model</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Konstantinova, Jelizaveta; Xu, Guanghua; He, Bo; Aminzadeh, Vahid; Xie, Jun; Wurdemann, Helge; Althoefer, Kaspar 2017-01-01 Haptic information in robotic surgery can significantly improve clinical outcomes and help detect hard soft-tissue inclusions that indicate potential abnormalities. Visual representation of tissue stiffness information is a cost-effective technique. Meanwhile, direct force feedback, although considerably more expensive than visual representation, is an intuitive method of conveying information regarding tissue stiffness to surgeons. In this study, real-time visual stiffness feedback by sliding indentation palpation is proposed, validated, and compared with force feedback involving human subjects. In an experimental tele-manipulation environment, a dynamically updated color map depicting the stiffness of probed soft tissue is presented via a graphical interface. The force feedback is provided, aided by a master haptic device. The haptic device uses data acquired from an F/T sensor attached to the end-effector of a tele-manipulated robot. Hard nodule detection performance is evaluated for 2 modes (force feedback and visual stiffness feedback) of stiffness feedback on an artificial organ containing buried stiff nodules. From this artificial organ, a virtual-environment tissue model is generated based on sliding indentation measurements. Employing this virtual-environment tissue model, we compare the performance of human participants in distinguishing differently sized hard nodules by force feedback and visual stiffness feedback. Results indicate that the proposed distributed visual representation of tissue stiffness can be used effectively for hard nodule identification. The representation can also be used as a sufficient substitute for force feedback in tissue palpation. PMID:28248996 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28248996','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28248996">Evaluation of stiffness feedback for hard nodule identification on a phantom silicone model.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Li, Min; Konstantinova, Jelizaveta; Xu, Guanghua; He, Bo; Aminzadeh, Vahid; Xie, Jun; Wurdemann, Helge; Althoefer, Kaspar 2017-01-01 Haptic information in robotic surgery can significantly improve clinical outcomes and help detect hard soft-tissue inclusions that indicate potential abnormalities. Visual representation of tissue stiffness information is a cost-effective technique. Meanwhile, direct force feedback, although considerably more expensive than visual representation, is an intuitive method of conveying information regarding tissue stiffness to surgeons. In this study, real-time visual stiffness feedback by sliding indentation palpation is proposed, validated, and compared with force feedback involving human subjects. In an experimental tele-manipulation environment, a dynamically updated color map depicting the stiffness of probed soft tissue is presented via a graphical interface. The force feedback is provided, aided by a master haptic device. The haptic device uses data acquired from an F/T sensor attached to the end-effector of a tele-manipulated robot. Hard nodule detection performance is evaluated for 2 modes (force feedback and visual stiffness feedback) of stiffness feedback on an artificial organ containing buried stiff nodules. From this artificial organ, a virtual-environment tissue model is generated based on sliding indentation measurements. Employing this virtual-environment tissue model, we compare the performance of human participants in distinguishing differently sized hard nodules by force feedback and visual stiffness feedback. Results indicate that the proposed distributed visual representation of tissue stiffness can be used effectively for hard nodule identification. The representation can also be used as a sufficient substitute for force feedback in tissue palpation. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JPhCS.783a2029K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JPhCS.783a2029K">Output-Feedback Model Predictive Control of a Pasteurization Pilot Plant based on an LPV model</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Karimi Pour, Fatemeh; Ocampo-Martinez, Carlos; Puig, Vicenç 2017-01-01 This paper presents a model predictive control (MPC) of a pasteurization pilot plant based on an LPV model. Since not all the states are measured, an observer is also designed, which allows implementing an output-feedback MPC scheme. However, the model of the plant is not completely observable when augmented with the disturbance models. In order to solve this problem, the following strategies are used: (i) the whole system is decoupled into two subsystems, (ii) an inner state-feedback controller is implemented into the MPC control scheme. A real-time example based on the pasteurization pilot plant is simulated as a case study for testing the behavior of the approaches. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JGRA..118.2359L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JGRA..118.2359L">Modeling terrestrial gamma ray flashes produced by relativistic feedback discharges</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Liu, Ningyu; Dwyer, Joseph R. 2013-05-01 This paper reports a modeling study of terrestrial gamma ray flashes (TGFs) produced by relativistic feedback discharges. Terrestrial gamma ray flashes are intense energetic radiation originating from the Earth's atmosphere that has been observed by spacecraft. They are produced by bremsstrahlung interactions of energetic electrons, known as runaway electrons, with air atoms. An efficient physical mechanism for producing large fluxes of the runaway electrons to make the TGFs is the relativistic feedback discharge, where seed runaway electrons are generated by positrons and X-rays, products of the discharge itself. Once the relativistic feedback discharge becomes self-sustaining, an exponentially increasing number of relativistic electron avalanches propagate through the same high-field region inside the thundercloud until the electric field is partially discharged by the ionization created by the discharge. The modeling results indicate that the durations of the TGF pulses produced by the relativistic feedback discharge vary from tens of microseconds to several milliseconds, encompassing all durations of the TGFs observed so far. In addition, when a sufficiently large potential difference is available in thunderclouds, a self-propagating discharge known as the relativistic feedback streamer can be formed, which propagates like a conventional positive streamer. For the relativistic feedback streamer, the positive feedback mechanism of runaway electron production by the positrons and X-rays plays a similar role as the photoionization for the conventional positive streamer. The simulation results of the relativistic feedback streamer show that a sequence of TGF pulses with varying durations can be produced by the streamer. The relativistic streamer may initially propagate with a pulsed manner and turn into a continuous propagation mode at a later stage. Milliseconds long TGF pulses can be produced by the feedback streamer during its continuous propagation. However </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.H51I1635L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.H51I1635L">Evaluating Land-Atmosphere Moisture Feedbacks in Earth System Models With Spaceborne Observations</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Levine, P. A.; Randerson, J. T.; Lawrence, D. M.; Swenson, S. C. 2016-12-01 We have developed a set of metrics for measuring the feedback loop between the land surface moisture state and the atmosphere globally on an interannual time scale. These metrics consider both the forcing of terrestrial water storage (TWS) on subsequent atmospheric conditions as well as the response of TWS to antecedent atmospheric conditions. We designed our metrics to take advantage of more than one decade's worth of satellite observations of TWS from the Gravity Recovery and Climate Experiment (GRACE) along with atmospheric variables from the Atmospheric Infrared Sounder (AIRS), the Global Precipitation Climatology Project (GPCP), and Clouds and the Earths Radiant Energy System (CERES). Metrics derived from spaceborne observations were used to evaluate the strength of the feedback loop in the Community Earth System Model (CESM) Large Ensemble (LENS) and in several models that contributed simulations to Phase 5 of the Coupled Model Intercomparison Project (CMIP5). We found that both forcing and response limbs of the feedback loop were generally stronger in tropical and temperate regions in CMIP5 models and even more so in LENS compared to satellite observations. Our analysis suggests that models may overestimate the strength of the feedbacks between the land surface and the atmosphere, which is consistent with previous studies conducted across different spatial and temporal scales. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19800045585&hterms=current+feedback&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dcurrent%2Bfeedback','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19800045585&hterms=current+feedback&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dcurrent%2Bfeedback">Effect of ice-albedo feedback on global sensitivity in a one-dimensional radiative-convective climate model</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Wang, W.-C.; Stone, P. H. 1980-01-01 The feedback between the ice albedo and temperature is included in a one-dimensional radiative-convective climate model. The effect of this feedback on global sensitivity to changes in solar constant is studied for the current climate conditions. This ice-albedo feedback amplifies global sensitivity by 26 and 39%, respectively, for assumptions of fixed cloud altitude and fixed cloud temperature. The global sensitivity is not affected significantly if the latitudinal variations of mean solar zenith angle and cloud cover are included in the global model. The differences in global sensitivity between one-dimensional radiative-convective models and energy balance models are examined. It is shown that the models are in close agreement when the same feedback mechanisms are included. The one-dimensional radiative-convective model with ice-albedo feedback included is used to compute the equilibrium ice line as a function of solar constant. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5855056','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5855056">Force Modeling, Identification, and Feedback Control of Robot-Assisted Needle Insertion: A Survey of the Literature</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Xie, Yu; Liu, Shuang; Sun, Dong 2018-01-01 Robot-assisted surgery is of growing interest in the surgical and engineering communities. The use of robots allows surgery to be performed with precision using smaller instruments and incisions, resulting in shorter healing times. However, using current technology, an operator cannot directly feel the operation because the surgeon-instrument and instrument-tissue interaction force feedbacks are lost during needle insertion. Advancements in force feedback and control not only help reduce tissue deformation and needle deflection but also provide the surgeon with better control over the surgical instruments. The goal of this review is to summarize the key components surrounding the force feedback and control during robot-assisted needle insertion. The literature search was conducted during the middle months of 2017 using mainstream academic search engines with a combination of keywords relevant to the field. In total, 166 articles with valuable contents were analyzed and grouped into five related topics. This survey systemically summarizes the state-of-the-art force control technologies for robot-assisted needle insertion, such as force modeling, measurement, the factors that influence the interaction force, parameter identification, and force control algorithms. All studies show force control is still at its initial stage. The influence factors, needle deflection or planning remain open for investigation in future. PMID:29439539 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29439539','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29439539">Force Modeling, Identification, and Feedback Control of Robot-Assisted Needle Insertion: A Survey of the Literature.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Yang, Chongjun; Xie, Yu; Liu, Shuang; Sun, Dong 2018-02-12 Robot-assisted surgery is of growing interest in the surgical and engineering communities. The use of robots allows surgery to be performed with precision using smaller instruments and incisions, resulting in shorter healing times. However, using current technology, an operator cannot directly feel the operation because the surgeon-instrument and instrument-tissue interaction force feedbacks are lost during needle insertion. Advancements in force feedback and control not only help reduce tissue deformation and needle deflection but also provide the surgeon with better control over the surgical instruments. The goal of this review is to summarize the key components surrounding the force feedback and control during robot-assisted needle insertion. The literature search was conducted during the middle months of 2017 using mainstream academic search engines with a combination of keywords relevant to the field. In total, 166 articles with valuable contents were analyzed and grouped into five related topics. This survey systemically summarizes the state-of-the-art force control technologies for robot-assisted needle insertion, such as force modeling, measurement, the factors that influence the interaction force, parameter identification, and force control algorithms. All studies show force control is still at its initial stage. The influence factors, needle deflection or planning remain open for investigation in future. </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li class="active">4</li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_5" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active">5</li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="81"> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ClDy...50.1209S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ClDy...50.1209S">Variability in modeled cloud feedback tied to differences in the climatological spatial pattern of clouds</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Siler, Nicholas; Po-Chedley, Stephen; Bretherton, Christopher S. 2018-02-01 Despite the increasing sophistication of climate models, the amount of surface warming expected from a doubling of atmospheric CO_2 (equilibrium climate sensitivity) remains stubbornly uncertain, in part because of differences in how models simulate the change in global albedo due to clouds (the shortwave cloud feedback). Here, model differences in the shortwave cloud feedback are found to be closely related to the spatial pattern of the cloud contribution to albedo (α) in simulations of the current climate: high-feedback models exhibit lower (higher) α in regions of warm (cool) sea-surface temperatures, and therefore predict a larger reduction in global-mean α as temperatures rise and warm regions expand. The spatial pattern of α is found to be strongly predictive (r=0.84) of a model's global cloud feedback, with satellite observations indicating a most-likely value of 0.58± 0.31 Wm^{-2} K^{-1} (90% confidence). This estimate is higher than the model-average cloud feedback of 0.43 Wm^{-2} K^{-1}, with half the range of uncertainty. The observational constraint on climate sensitivity is weaker but still significant, suggesting a likely value of 3.68 ± 1.30 K (90% confidence), which also favors the upper range of model estimates. These results suggest that uncertainty in model estimates of the global cloud feedback may be substantially reduced by ensuring a realistic distribution of clouds between regions of warm and cool SSTs in simulations of the current climate. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21456825','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21456825">Regular network model for the sea ice-albedo feedback in the Arctic.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Müller-Stoffels, Marc; Wackerbauer, Renate 2011-03-01 The Arctic Ocean and sea ice form a feedback system that plays an important role in the global climate. The complexity of highly parameterized global circulation (climate) models makes it very difficult to assess feedback processes in climate without the concurrent use of simple models where the physics is understood. We introduce a two-dimensional energy-based regular network model to investigate feedback processes in an Arctic ice-ocean layer. The model includes the nonlinear aspect of the ice-water phase transition, a nonlinear diffusive energy transport within a heterogeneous ice-ocean lattice, and spatiotemporal atmospheric and oceanic forcing at the surfaces. First results for a horizontally homogeneous ice-ocean layer show bistability and related hysteresis between perennial ice and perennial open water for varying atmospheric heat influx. Seasonal ice cover exists as a transient phenomenon. We also find that ocean heat fluxes are more efficient than atmospheric heat fluxes to melt Arctic sea ice. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000ClDy...16..393H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000ClDy...16..393H">Suppression of ENSO in a coupled model without water vapor feedback</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Hall, A.; Manabe, S. We examine 800-year time series of internally generated variability in both a coupled ocean-atmosphere model where water vapor anomalies are not allowed to interact with longwave radiation and one where they are. The ENSO-like phenomenon in the experiment without water vapor feedback is drastically suppressed both in amplitude and geographic extent relative to the experiment with water vapor feedback. Surprisingly, the reduced amplitude of ENSO-related sea surface temperature anomalies in the model without water vapor feedback cannot be attributed to greater longwave damping of sea surface temperature. (Differences between the two experiments in radiative feedback due to clouds counterbalance almost perfectly the differences in radiative feedback due to water vapor.) Rather, the interaction between water vapor anomalies and longwave radiation affects the ENSO-like phenomenon through its influence on the vertical structure of radiative heating: Because of the changes in water vapor associated with it, a given warm equatorial Pacific sea surface temperature anomaly is associated with a radiative heating profile that is much more gravitationally unstable when water vapor feedback is present. The warm sea surface temperature anomaly therefore results in more convection in the experiment with water vapor feedback. The increased convection, in turn, is related to a larger westerly wind-stress anomaly, which creates a larger decrease in upwelling of cold water, thereby enhancing the magnitude of the original warm sea surface temperature anomaly. In this manner, the interaction between water vapor anomalies and longwave radiation magnifies the air-sea interactions at the heart of the ENSO phenomenon; without this interaction, the coupling between sea surface temperature and wind stress is effectively reduced, resulting in smaller amplitude ENSO episodes with a more limited geographical extent. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/5021172-dynamic-coal-mine-model-generic-feedback-loop-model','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/5021172-dynamic-coal-mine-model-generic-feedback-loop-model">Dynamic coal mine model. [Generic feedback-loop model</a> <a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a> Hamilton, M.S. 1978-01-01 This study examines the determinants of the productive life cycle of a single hypothetical coal mine. The article addresses the questions of how long the mine will operate, what its annual production will be, and what percentage of the resource base will be recovered. As greatly expanded production requires capital investment, the investment decision is singled out as the principal determinant of the mine's dynamic behavior. A simple dynamic feedback loop model was constructed, the performance of which is compared with actual data to see how well the model can reproduce known behavior. Exogenous variables, such as the price ofmore » coal, the wage rate, operating costs, and the tax structure, are then changed to see how these changes affect the mine's performance.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018EJEE...43..552F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018EJEE...43..552F">Formative feedback and scaffolding for developing complex problem solving and modelling outcomes</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Frank, Brian; Simper, Natalie; Kaupp, James 2018-07-01 This paper discusses the use and impact of formative feedback and scaffolding to develop outcomes for complex problem solving in a required first-year course in engineering design and practice at a medium-sized research-intensive Canadian university. In 2010, the course began to use team-based, complex, open-ended contextualised problems to develop problem solving, communications, teamwork, modelling, and professional skills. Since then, formative feedback has been incorporated into: task and process-level feedback on scaffolded tasks in-class, formative assignments, and post-assignment review. Development in complex problem solving and modelling has been assessed through analysis of responses from student surveys, direct criterion-referenced assessment of course outcomes from 2013 to 2015, and an external longitudinal study. The findings suggest that students are improving in outcomes related to complex problem solving over the duration of the course. Most notably, the addition of new feedback and scaffolding coincided with improved student performance. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.A12A..05B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.A12A..05B">The cloud-phase feedback in the Super-parameterized Community Earth System Model</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Burt, M. A.; Randall, D. A. 2016-12-01 Recent comparisons of observations and climate model simulations by I. Tan and colleagues have suggested that the Wegener-Bergeron-Findeisen (WBF) process tends to be too active in climate models, making too much cloud ice, and resulting in an exaggerated negative cloud-phase feedback on climate change. We explore the WBF process and its effect on shortwave cloud forcing in present-day and future climate simulations with the Community Earth System Model, and its super-parameterized counterpart. Results show that SP-CESM has much less cloud ice and a weaker cloud-phase feedback than CESM. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19880047512&hterms=kernel&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dkernel','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19880047512&hterms=kernel&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dkernel">Factorization and the synthesis of optimal feedback kernels for differential-delay systems</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Milman, Mark M.; Scheid, Robert E. 1987-01-01 A combination of ideas from the theories of operator Riccati equations and Volterra factorizations leads to the derivation of a novel, relatively simple set of hyperbolic equations which characterize the optimal feedback kernel for the finite-time regulator problem for autonomous differential-delay systems. Analysis of these equations elucidates the underlying structure of the feedback kernel and leads to the development of fast and accurate numerical methods for its computation. Unlike traditional formulations based on the operator Riccati equation, the gain is characterized by means of classical solutions of the derived set of equations. This leads to the development of approximation schemes which are analogous to what has been accomplished for systems of ordinary differential equations with given initial conditions. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=cybernetics&pg=5&id=EJ248766','ERIC'); return false;" href="https://eric.ed.gov/?q=cybernetics&pg=5&id=EJ248766">Cybernetics: A Model for Feedback in the ESL Classroom.</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Zamel, Vivian 1981-01-01 Examines cybernetics as a model which provides framework with which to view communicators and the communications in the ESL classroom because it implies the kind of feedback the learner can assimilate and act upon. (Author/BK) </li> <li> <a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA225365','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA225365">Robustness of Feedback Systems with Several Modelling Errors</a> <a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a> 1990-06-01 Patterson AFB, OH 45433-6553 to help us maintain a current mailing list. Copies of this report should not be returned unless return is required by security...Wright Research (If applicable) and Development Center WRDC/FIGC F33615-88-C-3601 8c. ADDRESS (City, State, and ZIP Code) 10. SOURCE OF FUNDING NUMBERS...feedback systems with several sources of modelling uncertainty. We assume that each source of uncertainty is modelled as a stable unstructured </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19995170','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19995170">Using the 360 degrees multisource feedback model to evaluate teaching and professionalism.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Berk, Ronald A 2009-12-01 Student ratings have dominated as the primary and, frequently, only measure of teaching performance at colleges and universities for the past 50 years. Recently, there has been a trend toward augmenting those ratings with other data sources to broaden and deepen the evidence base. The 360 degrees multisource feedback (MSF) model used in management and industry for half a century and in clinical medicine for the last decade seemed like a best fit to evaluate teaching performance and professionalism. To adapt the 360 degrees MSF model to the assessment of teaching performance and professionalism of medical school faculty. The salient characteristics of the MSF models in industry and medicine were extracted from the literature. These characteristics along with 14 sources of evidence from eight possible raters, including students, self, peers, outside experts, mentors, alumni, employers, and administrators, based on the research in higher education were adapted to formative and summative decisions. Three 360 degrees MSF models were generated for three different decisions: (1) formative decisions and feedback about teaching improvement; (2) summative decisions and feedback for merit pay and contract renewal; and (3) formative decisions and feedback about professional behaviors in the academic setting. The characteristics of each model were listed. Finally, a top-10 list of the most persistent and, perhaps, intractable psychometric issues in executing these models was suggested to guide future research. The 360 degrees MSF model appears to be a useful framework for implementing a multisource evaluation of faculty teaching performance and professionalism in medical schools. This model can provide more accurate, reliable, fair, and equitable decisions than the one based on just a single source. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19980019502','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19980019502">Cloud Radiation Forcings and Feedbacks: General Circulation Model Tests and Observational Validation</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Lee,Wan-Ho; Iacobellis, Sam F.; Somerville, Richard C. J. 1997-01-01 Using an atmospheric general circulation model (the National Center for Atmospheric Research Community Climate Model: CCM2), the effects on climate sensitivity of several different cloud radiation parameterizations have been investigated. In addition to the original cloud radiation scheme of CCM2, four parameterizations incorporating prognostic cloud water were tested: one version with prescribed cloud radiative properties and three other versions with interactive cloud radiative properties. The authors' numerical experiments employ perpetual July integrations driven by globally constant sea surface temperature forcings of two degrees, both positive and negative. A diagnostic radiation calculation has been applied to investigate the partial contributions of high, middle, and low cloud to the total cloud radiative forcing, as well as the contributions of water vapor, temperature, and cloud to the net climate feedback. The high cloud net radiative forcing is positive, and the middle and low cloud net radiative forcings are negative. The total net cloud forcing is negative in all of the model versions. The effect of interactive cloud radiative properties on global climate sensitivity is significant. The net cloud radiative feedbacks consist of quite different shortwave and longwave components between the schemes with interactive cloud radiative properties and the schemes with specified properties. The increase in cloud water content in the warmer climate leads to optically thicker middle- and low-level clouds and in turn to negative shortwave feedbacks for the interactive radiative schemes, while the decrease in cloud amount simply produces a positive shortwave feedback for the schemes with a specified cloud water path. For the longwave feedbacks, the decrease in high effective cloudiness for the schemes without interactive radiative properties leads to a negative feedback, while for the other cases, the longwave feedback is positive. These cloud radiation </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1343748','DOE-PATENT-XML'); return false;" href="https://www.osti.gov/servlets/purl/1343748">System and method of designing models in a feedback loop</a> <a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a> Gosink, Luke C.; Pulsipher, Trenton C.; Sego, Landon H. 2017-02-14 A method and system for designing models is disclosed. The method includes selecting a plurality of models for modeling a common event of interest. The method further includes aggregating the results of the models and analyzing each model compared to the aggregate result to obtain comparative information. The method also includes providing the information back to the plurality of models to design more accurate models through a feedback loop. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.B24D..04B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.B24D..04B">Terrestrial Feedbacks Incorporated in Global Vegetation Models through Observed Trait-Environment Responses</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Bodegom, P. V. 2015-12-01 Most global vegetation models used to evaluate climate change impacts rely on plant functional types to describe vegetation responses to environmental stresses. In a traditional set-up in which vegetation characteristics are considered constant within a vegetation type, the possibility to implement and infer feedback mechanisms are limited as feedback mechanisms will likely involve a changing expression of community trait values. Based on community assembly concepts, we implemented functional trait-environment relationships into a global dynamic vegetation model to quantitatively assess this feature. For the current climate, a different global vegetation distribution was calculated with and without the inclusion of trait variation, emphasizing the importance of feedbacks -in interaction with competitive processes- for the prevailing global patterns. These trait-environmental responses do, however, not necessarily imply adaptive responses of vegetation to changing conditions and may locally lead to a faster turnover in vegetation upon climate change. Indeed, when running climate projections, simulations with trait variation did not yield a more stable or resilient vegetation than those without. Through the different feedback expressions, global and regional carbon and water fluxes were -however- strongly altered. At a global scale, model projections suggest an increased productivity and hence an increased carbon sink in the next decades to come, when including trait variation. However, by the end of the century, a reduced carbon sink is projected. This effect is due to a downregulation of photosynthesis rates, particularly in the tropical regions, even when accounting for CO2-fertilization effects. Altogether, the various global model simulations suggest the critical importance of including vegetation functional responses to changing environmental conditions to grasp terrestrial feedback mechanisms at global scales in the light of climate change. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25112445','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25112445">Confounding factors in using upward feedback to assess the quality of medical training: a systematic review.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Zhou, Anli Yue; Baker, Paul 2014-01-01 Upward feedback is becoming more widely used in medical training as a means of quality control. Multiple biases exist, thus the accuracy of upward feedback is debatable. This study aims to identify factors that could influence upward feedback, especially in medical training. A systematic review using a structured search strategy was performed. Thirty-five databases were searched. Results were reviewed and relevant abstracts were shortlisted. All studies in English, both medical and non-medical literature, were included. A simple pro-forma was used initially to identify the pertinent areas of upward feedback, so that a focused pro-forma could be designed for data extraction. A total of 204 articles were reviewed. Most studies on upward feedback bias were evaluative studies and only covered Kirkpatrick level 1-reaction. Most studies evaluated trainers or training, were used for formative purposes and presented quantitative data. Accountability and confidentiality were the most common overt biases, whereas method of feedback was the most commonly implied bias within articles. Although different types of bias do exist, upward feedback does have a role in evaluating medical training. Accountability and confidentiality were the most common biases. Further research is required to evaluate which types of bias are associated with specific survey characteristics and which are potentially modifiable. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4697281','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4697281">Reciprocal Markov modeling of feedback mechanisms between emotion and dietary choice using experience sampling data</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Lu, Ji; Pan, Junhao; Zhang, Qiang; Dubé, Laurette; Ip, Edward H. 2015-01-01 With intensively collected longitudinal data, recent advances in Experience Sampling Method (ESM) benefit social science empirical research, but also pose important methodological challenges. As traditional statistical models are not generally well-equipped to analyze a system of variables that contain feedback loops, this paper proposes the utility of an extended hidden Markov model to model reciprocal relationship between momentary emotion and eating behavior. This paper revisited an ESM data set (Lu, Huet & Dube, 2011) that observed 160 participants’ food consumption and momentary emotions six times per day in 10 days. Focusing on the analyses on feedback loop between mood and meal healthiness decision, the proposed Reciprocal Markov Model (RMM) can accommodate both hidden (“general” emotional states: positive vs. negative state) and observed states (meal: healthier, same or less healthy than usual) without presuming independence between observations and smooth trajectories of mood or behavior changes. The results of RMM analyses illustrated the reciprocal chains of meal consumption and mood as well as the effect of contextual factors that moderate the interrelationship between eating and emotion. A simulation experiment that generated data consistent to the empirical study further demonstrated that the procedure is promising in terms of recovering the parameters. PMID:26717120 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26717120','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26717120">Reciprocal Markov Modeling of Feedback Mechanisms Between Emotion and Dietary Choice Using Experience-Sampling Data.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Lu, Ji; Pan, Junhao; Zhang, Qiang; Dubé, Laurette; Ip, Edward H 2015-01-01 With intensively collected longitudinal data, recent advances in the experience-sampling method (ESM) benefit social science empirical research, but also pose important methodological challenges. As traditional statistical models are not generally well equipped to analyze a system of variables that contain feedback loops, this paper proposes the utility of an extended hidden Markov model to model reciprocal the relationship between momentary emotion and eating behavior. This paper revisited an ESM data set (Lu, Huet, & Dube, 2011) that observed 160 participants' food consumption and momentary emotions 6 times per day in 10 days. Focusing on the analyses on feedback loop between mood and meal-healthiness decision, the proposed reciprocal Markov model (RMM) can accommodate both hidden ("general" emotional states: positive vs. negative state) and observed states (meal: healthier, same or less healthy than usual) without presuming independence between observations and smooth trajectories of mood or behavior changes. The results of RMM analyses illustrated the reciprocal chains of meal consumption and mood as well as the effect of contextual factors that moderate the interrelationship between eating and emotion. A simulation experiment that generated data consistent with the empirical study further demonstrated that the procedure is promising in terms of recovering the parameters. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhRvP...6d4020B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhRvP...6d4020B">Suppression of Spontaneous Gas Oscillations by Acoustic Self-Feedback</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Biwa, Tetsushi; Sawada, Yoshiki; Hyodo, Hiroaki; Kato, Soichiro 2016-10-01 This paper demonstrates a method of acoustical self-feedback to suppress spontaneous gas oscillations such as those observed in combustors of gas-turbine engines. Whereas a conventional feedback system consists of electromechanical devices, the present method achieves acoustical self-feedback with a hollow tube that connects two positions of the oscillation system. A model oscillator of combustion-driven gas oscillations is designed and built to demonstrate the applicability of the self-feedback concept. Stability analysis through measurements of Q values (quality factor) of oscillations shows that the desired delay time and gain are obtained when the tube length is equal to the odd integer times half the wavelength of the anticipated acoustic oscillations. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29456494','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29456494">The Influence of Feedback on Task-Switching Performance: A Drift Diffusion Modeling Account.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Cohen Hoffing, Russell; Karvelis, Povilas; Rupprechter, Samuel; Seriès, Peggy; Seitz, Aaron R 2018-01-01 Task-switching is an important cognitive skill that facilitates our ability to choose appropriate behavior in a varied and changing environment. Task-switching training studies have sought to improve this ability by practicing switching between multiple tasks. However, an efficacious training paradigm has been difficult to develop in part due to findings that small differences in task parameters influence switching behavior in a non-trivial manner. Here, for the first time we employ the Drift Diffusion Model (DDM) to understand the influence of feedback on task-switching and investigate how drift diffusion parameters change over the course of task switch training. We trained 316 participants on a simple task where they alternated sorting stimuli by color or by shape. Feedback differed in six different ways between subjects groups, ranging from No Feedback (NFB) to a variety of manipulations addressing trial-wise vs. Block Feedback (BFB), rewards vs. punishments, payment bonuses and different payouts depending upon the trial type (switch/non-switch). While overall performance was found to be affected by feedback, no effect of feedback was found on task-switching learning. Drift Diffusion Modeling revealed that the reductions in reaction time (RT) switch cost over the course of training were driven by a continually decreasing decision boundary. Furthermore, feedback effects on RT switch cost were also driven by differences in decision boundary, but not in drift rate. These results reveal that participants systematically modified their task-switching performance without yielding an overall gain in performance. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009NIMPA.610..204K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009NIMPA.610..204K">Application of simple negative feedback model for avalanche photodetectors investigation</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Kushpil, V. V. 2009-10-01 A simple negative feedback model based on Miller's formula is used to investigate the properties of Avalanche Photodetectors (APDs). The proposed method can be applied to study classical APD as well as new type of devices, which are operating in the Internal Negative Feedback (INF) regime. The method shows a good sensitivity to technological APD parameters making it possible to use it as a tool to analyse various APD parameters. It also allows better understanding of the APD operation conditions. The simulations and experimental data analysis for different types of APDs are presented. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19820049100&hterms=riser&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Driser','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19820049100&hterms=riser&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Driser">VLF wave growth and discrete emission triggering in the magnetosphere - A feedback model</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Helliwell, R. A.; Inan, U. S. 1982-01-01 A simple nonlinear feedback model is presented to explain VLF wave growth and emission triggering observed in VLF transmission experiments. The model is formulated in terms of the interaction of electrons with a slowly varying wave in an inhomogeneous medium as in an unstable feedback amplifier with a delay line; constant frequency oscillations are generated on the magnetic equator, while risers and fallers are generated on the downstream and upstream sides of the equator, respectively. Quantitative expressions are obtained for the stimulated radiation produced by energy exchanged between energetic electrons and waves by Doppler-shifted cyclotron resonance, and feedback between the stimulated radiation and the phase bunched currents is incorporated in terms of a two-port discrete time model. The resulting model is capable of explaining the observed temporal growth and saturation effects, phase advance, retardation or frequency shift during growth in the context of a single parameter depending on the energetic particle distribution function, as well as pretermination triggering. </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active">5</li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_6" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active">6</li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="101"> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29906855','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29906855">Effects of stochastic time-delayed feedback on a dynamical system modeling a chemical oscillator.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> González Ochoa, Héctor O; Perales, Gualberto Solís; Epstein, Irving R; Femat, Ricardo 2018-05-01 We examine how stochastic time-delayed negative feedback affects the dynamical behavior of a model oscillatory reaction. We apply constant and stochastic time-delayed negative feedbacks to a point Field-Körös-Noyes photosensitive oscillator and compare their effects. Negative feedback is applied in the form of simulated inhibitory electromagnetic radiation with an intensity proportional to the concentration of oxidized light-sensitive catalyst in the oscillator. We first characterize the system under nondelayed inhibitory feedback; then we explore and compare the effects of constant (deterministic) versus stochastic time-delayed feedback. We find that the oscillatory amplitude, frequency, and waveform are essentially preserved when low-dispersion stochastic delayed feedback is used, whereas small but measurable changes appear when a large dispersion is applied. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PhRvE..97e2214G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PhRvE..97e2214G">Effects of stochastic time-delayed feedback on a dynamical system modeling a chemical oscillator</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> González Ochoa, Héctor O.; Perales, Gualberto Solís; Epstein, Irving R.; Femat, Ricardo 2018-05-01 We examine how stochastic time-delayed negative feedback affects the dynamical behavior of a model oscillatory reaction. We apply constant and stochastic time-delayed negative feedbacks to a point Field-Körös-Noyes photosensitive oscillator and compare their effects. Negative feedback is applied in the form of simulated inhibitory electromagnetic radiation with an intensity proportional to the concentration of oxidized light-sensitive catalyst in the oscillator. We first characterize the system under nondelayed inhibitory feedback; then we explore and compare the effects of constant (deterministic) versus stochastic time-delayed feedback. We find that the oscillatory amplitude, frequency, and waveform are essentially preserved when low-dispersion stochastic delayed feedback is used, whereas small but measurable changes appear when a large dispersion is applied. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1239215-forcing-feedbacks-climate-sensitivity-cmip5-coupled-atmosphere-ocean-climate-models','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1239215-forcing-feedbacks-climate-sensitivity-cmip5-coupled-atmosphere-ocean-climate-models">Forcing, feedbacks and climate sensitivity in CMIP5 coupled atmosphere-ocean climate models</a> <a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a> Andrews, Timothy; Gregory, Jonathan M.; Webb, Mark J.; ... 2012-05-15 We quantify forcing and feedbacks across available CMIP5 coupled atmosphere-ocean general circulation models (AOGCMs) by analysing simulations forced by an abrupt quadrupling of atmospheric carbon dioxide concentration. This is the first application of the linear forcing-feedback regression analysis of Gregory et al. (2004) to an ensemble of AOGCMs. The range of equilibrium climate sensitivity is 2.1–4.7 K. Differences in cloud feedbacks continue to be important contributors to this range. Some models show small deviations from a linear dependence of top-of-atmosphere radiative fluxes on global surface temperature change. We show that this phenomenon largely arises from shortwave cloud radiative effects overmore » the ocean and is consistent with independent estimates of forcing using fixed sea-surface temperature methods. Moreover, we suggest that future research should focus more on understanding transient climate change, including any time-scale dependence of the forcing and/or feedback, rather than on the equilibrium response to large instantaneous forcing.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19790012522','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19790012522">Incorporation of surface albedo-temperature feedback in a one-dimensional radiative-connective climate model</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Wang, W. C.; Stone, P. H. 1979-01-01 The feedback between ice snow albedo and temperature is included in a one dimensional radiative convective climate model. The effect of this feedback on sensitivity to changes in solar constant is studied for the current values of the solar constant and cloud characteristics. The ice snow albedo feedback amplifies global climate sensitivity by 33% and 50%, respectively, for assumptions of constant cloud altitude and constant cloud temperature. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28979827','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28979827">Active Learning of Classification Models with Likert-Scale Feedback.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Xue, Yanbing; Hauskrecht, Milos 2017-01-01 Annotation of classification data by humans can be a time-consuming and tedious process. Finding ways of reducing the annotation effort is critical for building the classification models in practice and for applying them to a variety of classification tasks. In this paper, we develop a new active learning framework that combines two strategies to reduce the annotation effort. First, it relies on label uncertainty information obtained from the human in terms of the Likert-scale feedback. Second, it uses active learning to annotate examples with the greatest expected change. We propose a Bayesian approach to calculate the expectation and an incremental SVM solver to reduce the time complexity of the solvers. We show the combination of our active learning strategy and the Likert-scale feedback can learn classification models more rapidly and with a smaller number of labeled instances than methods that rely on either Likert-scale labels or active learning alone. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5624557','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5624557">Active Learning of Classification Models with Likert-Scale Feedback</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Xue, Yanbing; Hauskrecht, Milos 2017-01-01 Annotation of classification data by humans can be a time-consuming and tedious process. Finding ways of reducing the annotation effort is critical for building the classification models in practice and for applying them to a variety of classification tasks. In this paper, we develop a new active learning framework that combines two strategies to reduce the annotation effort. First, it relies on label uncertainty information obtained from the human in terms of the Likert-scale feedback. Second, it uses active learning to annotate examples with the greatest expected change. We propose a Bayesian approach to calculate the expectation and an incremental SVM solver to reduce the time complexity of the solvers. We show the combination of our active learning strategy and the Likert-scale feedback can learn classification models more rapidly and with a smaller number of labeled instances than methods that rely on either Likert-scale labels or active learning alone. PMID:28979827 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22617253-theoretical-modeling-dynamics-semiconductor-laser-subject-double-reflector-optical-feedback','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22617253-theoretical-modeling-dynamics-semiconductor-laser-subject-double-reflector-optical-feedback">Theoretical modeling of the dynamics of a semiconductor laser subject to double-reflector optical feedback</a> <a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a> Bakry, A.; Abdulrhmann, S.; Ahmed, M., E-mail: mostafa.farghal@mu.edu.eg 2016-06-15 We theoretically model the dynamics of semiconductor lasers subject to the double-reflector feedback. The proposed model is a new modification of the time-delay rate equations of semiconductor lasers under the optical feedback to account for this type of the double-reflector feedback. We examine the influence of adding the second reflector to dynamical states induced by the single-reflector feedback: periodic oscillations, period doubling, and chaos. Regimes of both short and long external cavities are considered. The present analyses are done using the bifurcation diagram, temporal trajectory, phase portrait, and fast Fourier transform of the laser intensity. We show that adding themore » second reflector attracts the periodic and perioddoubling oscillations, and chaos induced by the first reflector to a route-to-continuous-wave operation. During this operation, the periodic-oscillation frequency increases with strengthening the optical feedback. We show that the chaos induced by the double-reflector feedback is more irregular than that induced by the single-reflector feedback. The power spectrum of this chaos state does not reflect information on the geometry of the optical system, which then has potential for use in chaotic (secure) optical data encryption.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27612004','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27612004">Student conceptions of feedback: Impact on self-regulation, self-efficacy, and academic achievement.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Brown, Gavin T L; Peterson, Elizabeth R; Yao, Esther S 2016-12-01 Lecturers give feedback on assessed work in the hope that students will take it on board and use it to help regulate their learning for the next assessment. However, little is known about how students' conceptions of feedback relate to students' self-regulated learning and self-efficacy beliefs and academic performance. This study explores student beliefs about the role and purpose of feedback and the relationship of those beliefs to self-reported self-regulation and self-efficacy, and achievement. A total of 278 university students in a general education course on learning theory and approaches in a research-intensive university. Self-reported survey responses for students' conceptions of feedback (SCoF), self-regulation (SRL), academic self-efficacy (ASE), and Grade Point Average (GPA) were evaluated first with confirmatory factor analysis and then interlinked in a structural equation model. Three SCoF factors predicted SRL and/or GPA. The SCoF factor 'I use feedback' had positive associations with SRL (β = .44), GPA (β = .45), and ASE (β = .15). The SCoF factors 'tutor/marker comments' and 'peers help' both had negative relations to GPA (β = -.41 and -.16, respectively). 'Peers help' had a positive connection to SRL (β = .21). ASE itself made a small contribution to overall GPA (β = .16), while SRL had no statistically significant relation to GPA. The model indicates the centrality of believing that feedback exists to guide next steps in learning and thus contributes to SRL, ASE, and increased GPA. © 2016 The British Psychological Society. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11125662','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11125662">An integrated model of feedback-seeking behavior: disposition, context, and cognition.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> VandeWalle, D; Ganesan, S; Challagalla, G N; Brown, S P 2000-12-01 This study replicates, integrates, and extends prior research on the dispositional, contextual, and cognitive antecedents of feedback-seeking behavior. Regression analysis was used to analyze data collected from a sample of salespeople (N = 310) from 2 Fortune 500 companies. The study hypotheses were supported with the following results. First, the individual disposition of learning goal orientation and the contextual factors of leader consideration and leader initiation of structure influenced cognitions about the perceived cost and value of feedback seeking. Second, the strength of the relationship of learning goal orientation with the cost and value perceptions was moderated by the leadership style of the supervisor. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18923042','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18923042">Shared internal models for feedforward and feedback control.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Wagner, Mark J; Smith, Maurice A 2008-10-15 A child often learns to ride a bicycle in the driveway, free of unforeseen obstacles. Yet when she first rides in the street, we hope that if a car suddenly pulls out in front of her, she will combine her innate goal of avoiding an accident with her learned knowledge of the bicycle, and steer away or brake. In general, when we train to perform a new motor task, our learning is most robust if it updates the rules of online error correction to reflect the rules and goals of the new task. Here we provide direct evidence that, after a new feedforward motor adaptation, motor feedback responses to unanticipated errors become precisely task appropriate, even when such errors were never experienced during training. To study this ability, we asked how, if at all, do online responses to occasional, unanticipated force pulses during reaching arm movements change after adapting to altered arm dynamics? Specifically, do they change in a task-appropriate manner? In our task, subjects learned novel velocity-dependent dynamics. However, occasional force-pulse perturbations produced unanticipated changes in velocity. Therefore, after adaptation, task-appropriate responses to unanticipated pulses should compensate corresponding changes in velocity-dependent dynamics. We found that after adaptation, pulse responses precisely compensated these changes, although they were never trained to do so. These results provide evidence for a smart feedback controller which automatically produces responses specific to the learned dynamics of the current task. To accomplish this, the neural processes underlying feedback control must (1) be capable of accurate real-time state prediction for velocity via a forward model and (2) have access to recently learned changes in internal models of limb dynamics. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/7278811-ripple-feedback-resonant-filter-unity-power-factor-rectifier','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/7278811-ripple-feedback-resonant-filter-unity-power-factor-rectifier">Ripple feedback for the resonant-filter unity-power-factor rectifier</a> <a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a> Streng, S.A.; King, R.J. 1992-07-01 An unusual bucklike unity-power-factor rectifier with a resonant load-balancing network permits current-limited operation down to zero output voltage in a single-stage-topology. However, this rectifier has been found to be sensitive to ac-line voltage distortion and is potentially unstable with realistic values of ac-line impedance. In this paper, a new ripple feedback is proposed that solves both problems. A large-signal time-varying analysis is given along with incremental, quasi-static, and low-frequency approximations. Experimental verification is provided by a 500-W 50-kHz rectifier operating from the 120-V 60-Hz distribution system. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=marketing+AND+effect&pg=4&id=EJ1132685','ERIC'); return false;" href="https://eric.ed.gov/?q=marketing+AND+effect&pg=4&id=EJ1132685">The Effects of Source, Revision Possibility, and Amount of Feedback on Marketing Students' Impressions of Feedback on an Assignment</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Ackerman, David S.; Dommeyer, Curt J.; Gross, Barbara L. 2017-01-01 This study examines how three factors affect students' reactions to critical feedback on an assignment--amount of feedback (none vs. low amount vs. high amount), source of feedback (instructor-provided feedback vs. peer-provided feedback), and the situational context of the feedback (revision of paper is or is not possible). An incomplete 3 × 2 ×… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1357404-cloud-feedback-mechanisms-representation-global-climate-models','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1357404-cloud-feedback-mechanisms-representation-global-climate-models">Cloud feedback mechanisms and their representation in global climate models</a> <a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a> Ceppi, Paulo; Brient, Florent; Zelinka, Mark D.; ... 2017-05-11 Cloud feedback—the change in top-of-atmosphere radiative flux resulting from the cloud response to warming—constitutes by far the largest source of uncertainty in the climate response to CO 2 forcing simulated by global climate models (GCMs). In this paper, we review the main mechanisms for cloud feedbacks, and discuss their representation in climate models and the sources of intermodel spread. Global-mean cloud feedback in GCMs results from three main effects: (1) rising free-tropospheric clouds (a positive longwave effect); (2) decreasing tropical low cloud amount (a positive shortwave [SW] effect); (3) increasing high-latitude low cloud optical depth (a negative SW effect). Thesemore » cloud responses simulated by GCMs are qualitatively supported by theory, high-resolution modeling, and observations. Rising high clouds are consistent with the fixed anvil temperature (FAT) hypothesis, whereby enhanced upper-tropospheric radiative cooling causes anvil cloud tops to remain at a nearly fixed temperature as the atmosphere warms. Tropical low cloud amount decreases are driven by a delicate balance between the effects of vertical turbulent fluxes, radiative cooling, large-scale subsidence, and lower-tropospheric stability on the boundary-layer moisture budget. High-latitude low cloud optical depth increases are dominated by phase changes in mixed-phase clouds. Finally, the causes of intermodel spread in cloud feedback are discussed, focusing particularly on the role of unresolved parameterized processes such as cloud microphysics, turbulence, and convection.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1357404','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/1357404">Cloud feedback mechanisms and their representation in global climate models</a> <a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a> Ceppi, Paulo; Brient, Florent; Zelinka, Mark D. Cloud feedback—the change in top-of-atmosphere radiative flux resulting from the cloud response to warming—constitutes by far the largest source of uncertainty in the climate response to CO 2 forcing simulated by global climate models (GCMs). In this paper, we review the main mechanisms for cloud feedbacks, and discuss their representation in climate models and the sources of intermodel spread. Global-mean cloud feedback in GCMs results from three main effects: (1) rising free-tropospheric clouds (a positive longwave effect); (2) decreasing tropical low cloud amount (a positive shortwave [SW] effect); (3) increasing high-latitude low cloud optical depth (a negative SW effect). Thesemore » cloud responses simulated by GCMs are qualitatively supported by theory, high-resolution modeling, and observations. Rising high clouds are consistent with the fixed anvil temperature (FAT) hypothesis, whereby enhanced upper-tropospheric radiative cooling causes anvil cloud tops to remain at a nearly fixed temperature as the atmosphere warms. Tropical low cloud amount decreases are driven by a delicate balance between the effects of vertical turbulent fluxes, radiative cooling, large-scale subsidence, and lower-tropospheric stability on the boundary-layer moisture budget. High-latitude low cloud optical depth increases are dominated by phase changes in mixed-phase clouds. Finally, the causes of intermodel spread in cloud feedback are discussed, focusing particularly on the role of unresolved parameterized processes such as cloud microphysics, turbulence, and convection.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=mental+AND+models+AND+decision+AND+making&id=EJ852817','ERIC'); return false;" href="https://eric.ed.gov/?q=mental+AND+models+AND+decision+AND+making&id=EJ852817">A Feedback Learning and Mental Models Perspective on Strategic Decision Making</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Capelo, Carlos; Dias, Joao Ferreira 2009-01-01 This study aims to be a contribution to a theoretical model that explains the effectiveness of the learning and decision-making processes by means of a feedback and mental models perspective. With appropriate mental models, managers should be able to improve their capacity to deal with dynamically complex contexts, in order to achieve long-term… </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JSMTE..07..020Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JSMTE..07..020Z">Modeling mutual feedback between users and recommender systems</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Zeng, An; Yeung, Chi Ho; Medo, Matúš; Zhang, Yi-Cheng 2015-07-01 Recommender systems daily influence our decisions on the Internet. While considerable attention has been given to issues such as recommendation accuracy and user privacy, the long-term mutual feedback between a recommender system and the decisions of its users has been neglected so far. We propose here a model of network evolution which allows us to study the complex dynamics induced by this feedback, including the hysteresis effect which is typical for systems with non-linear dynamics. Despite the popular belief that recommendation helps users to discover new things, we find that the long-term use of recommendation can contribute to the rise of extremely popular items and thus ultimately narrow the user choice. These results are supported by measurements of the time evolution of item popularity inequality in real systems. We show that this adverse effect of recommendation can be tamed by sacrificing part of short-term recommendation accuracy. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20090029958','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20090029958">Evaluating Effectiveness of Modeling Motion System Feedback in the Enhanced Hess Structural Model of the Human Operator</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Zaychik, Kirill; Cardullo, Frank; George, Gary; Kelly, Lon C. 2009-01-01 In order to use the Hess Structural Model to predict the need for certain cueing systems, George and Cardullo significantly expanded it by adding motion feedback to the model and incorporating models of the motion system dynamics, motion cueing algorithm and a vestibular system. This paper proposes a methodology to evaluate effectiveness of these innovations by performing a comparison analysis of the model performance with and without the expanded motion feedback. The proposed methodology is composed of two stages. The first stage involves fine-tuning parameters of the original Hess structural model in order to match the actual control behavior recorded during the experiments at NASA Visual Motion Simulator (VMS) facility. The parameter tuning procedure utilizes a new automated parameter identification technique, which was developed at the Man-Machine Systems Lab at SUNY Binghamton. In the second stage of the proposed methodology, an expanded motion feedback is added to the structural model. The resulting performance of the model is then compared to that of the original one. As proposed by Hess, metrics to evaluate the performance of the models include comparison against the crossover models standards imposed on the crossover frequency and phase margin of the overall man-machine system. Preliminary results indicate the advantage of having the model of the motion system and motion cueing incorporated into the model of the human operator. It is also demonstrated that the crossover frequency and the phase margin of the expanded model are well within the limits imposed by the crossover model. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3197337','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3197337">Regulated recovery of pulsatile growth hormone secretion from negative feedback: a preclinical investigation</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Bowers, Cyril Y. 2011-01-01 Although stimulatory (feedforward) and inhibitory (feedback) dynamics jointly control neurohormone secretion, the factors that supervise feedback restraint are poorly understood. To parse the regulation of growth hormone (GH) escape from negative feedback, 25 healthy men and women were studied eight times each during an experimental GH feedback clamp. The clamp comprised combined bolus infusion of GH or saline and continuous stimulation by saline GH-releasing hormone (GHRH), GHRP-2, or both peptides after randomly ordered supplementation with placebo (both sexes) vs. E2 (estrogen; women) and T (testosterone; men). Endpoints were GH pulsatility and entropy (a model-free measure of feedback quenching). Gender determined recovery of pulsatile GH secretion from negative feedback in all four secretagog regimens (0.003 ≤ P ≤ 0.017 for women>men). Peptidyl secretagog controlled the mass, number, and duration of feedback-inhibited GH secretory bursts (each, P < 0.001). E2/T administration potentiated both pulsatile (P = 0.006) and entropic (P < 0.001) modes of GH recovery. IGF-I positively predicted the escape of GH secretory burst number and mode (P = 0.022), whereas body mass index negatively forecast GH secretory burst number and mass (P = 0.005). The composite of gender, body mass index, E2, IGF-I, and peptidyl secretagog strongly regulates the escape of pulsatile and entropic GH secretion from autonegative feedback. The ensemble factors identified in this preclinical investigation enlarge the dynamic model of GH control in humans. PMID:21795635 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4798729','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4798729">Feedback, Lineages and Self-Organizing Morphogenesis</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Calof, Anne L.; Lowengrub, John S.; Lander, Arthur D. 2016-01-01 Feedback regulation of cell lineage progression plays an important role in tissue size homeostasis, but whether such feedback also plays an important role in tissue morphogenesis has yet to be explored. Here we use mathematical modeling to show that a particular feedback architecture in which both positive and negative diffusible signals act on stem and/or progenitor cells leads to the appearance of bistable or bi-modal growth behaviors, ultrasensitivity to external growth cues, local growth-driven budding, self-sustaining elongation, and the triggering of self-organization in the form of lamellar fingers. Such behaviors arise not through regulation of cell cycle speeds, but through the control of stem or progenitor self-renewal. Even though the spatial patterns that arise in this setting are the result of interactions between diffusible factors with antagonistic effects, morphogenesis is not the consequence of Turing-type instabilities. PMID:26989903 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3753843','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3753843">A Negative-Feedback Loop between the Detoxification/Antioxidant Response Factor SKN-1 and Its Repressor WDR-23 Matches Organism Needs with Environmental Conditions</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Leung, Chi K.; Wang, Ying; Deonarine, Andrew; Tang, Lanlan; Prasse, Stephanie 2013-01-01 Negative-feedback loops between transcription factors and repressors in responses to xenobiotics, oxidants, heat, hypoxia, DNA damage, and infection have been described. Although common, the function of feedback is largely unstudied. Here, we define a negative-feedback loop between the Caenorhabditis elegans detoxification/antioxidant response factor SKN-1/Nrf and its repressor wdr-23 and investigate its function in vivo. Although SKN-1 promotes stress resistance and longevity, we find that tight regulation by WDR-23 is essential for growth and reproduction. By disabling SKN-1 transactivation of wdr-23, we reveal that feedback is required to set the balance between growth/reproduction and stress resistance/longevity. We also find that feedback is required to set the sensitivity of a core SKN-1 target gene to an electrophile. Interestingly, the effect of feedback on target gene induction is greatly reduced when the stress response is strongly activated, presumably to ensure maximum activation of cytoprotective genes during potentially fatal conditions. Our work provides a framework for understanding the function of negative feedback in inducible stress responses and demonstrates that manipulation of feedback alone can shift the balance of competing animal processes toward cell protection, health, and longevity. PMID:23836880 </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active">6</li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_7" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active">7</li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="121"> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.A51G2152Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.A51G2152Y">Effect of aerosol feedback in the Korea Peninsula using WRF-CMAQ two-way coupled model</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Yoo, J.; Jeon, W.; Lee, H.; Lee, S. 2017-12-01 Aerosols influence the climate system by scattering and absorption of the solar radiation by altering the cloud radiative properties. For the reason, consideration of aerosol feedback is important numerical weather prediction and air quality models. The purpose of this study was to investigate the effect of aerosol feedback on PM10 simulation in Korean Peninsula using the Weather Research and Forecasting (WRF) and the community multiscale air quality (CMAQ) two-way coupled model. Simulations were conducted with the aerosol feedback (FB) and without (NFB). The results of the simulated solar radiation in the west part of Korea decreased due to the aerosol feedback effect. The feedback effect was significant in the west part of Korea Peninsula, showing high Particulate Matter (PM) estimates due to dense emissions and its long-range transport from China. The decrease of solar radiation lead to planetary boundary layer (PBL) height reduction, thereby dispersion of air pollutants such as PM is suppressed, and resulted in higher PM concentrations. These results indicate that aerosol feedback effects can play an important role in the simulation of meteorology and air quality over Korea Peninsula. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28770891','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28770891">Feedback in a clinical setting: A way forward to enhance student's learning through constructive feedback.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Sultan, Amber Shamim; Mateen Khan, Muhammad Arif 2017-07-01 Feedback is considered as a dynamic process in which information about the observed performance is used to promote the desirable behaviour and correct the negative ones. The importance of feedback is widely acknowledged, but still there seems to be inconsistency in the amount, type and timing of feedback received from the clinical faculty. No significant effort has been put forward from the educator end to empower the learners with the skills of receiving and using the feedback effectively. Some institutions conduct faculty development workshops and courses to facilitate the clinicians on how best to deliver constructive feedback to the learners. Despite of all these struggles learners are not fully satisfied with the quality of feedback received from their busy clinicians. The aim of this paper is to highlight what actually feedback is, type and structure of feedback, the essential components of a constructive feedback, benefits of providing feedback, barriers affecting the provision of timely feedback and different models used for providing feedback. The ultimate purpose of this paper is to provide sufficient information to the clinical directors that there is a need to establish a robust system for giving feedback to learners and to inform all the clinical educators with the skills required to provide constructive feedback to their learners. For the literature review, we had used the key words glossary as: Feedback, constructive feedback, barriers to feedback, principles of constructive feedback, Models of feedback, reflection, self-assessment and clinical practice etc. The data bases for the search include: Cardiff University library catalogue, Pub Med, Google Scholar, Web of Knowledge and Science direct. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006PhPl...13a2512S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006PhPl...13a2512S">Adaptive optimal stochastic state feedback control of resistive wall modes in tokamaks</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Sun, Z.; Sen, A. K.; Longman, R. W. 2006-01-01 An adaptive optimal stochastic state feedback control is developed to stabilize the resistive wall mode (RWM) instability in tokamaks. The extended least-square method with exponential forgetting factor and covariance resetting is used to identify (experimentally determine) the time-varying stochastic system model. A Kalman filter is used to estimate the system states. The estimated system states are passed on to an optimal state feedback controller to construct control inputs. The Kalman filter and the optimal state feedback controller are periodically redesigned online based on the identified system model. This adaptive controller can stabilize the time-dependent RWM in a slowly evolving tokamak discharge. This is accomplished within a time delay of roughly four times the inverse of the growth rate for the time-invariant model used. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007JFuE...26..211S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007JFuE...26..211S">Adaptive Optimal Stochastic State Feedback Control of Resistive Wall Modes in Tokamaks</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Sun, Z.; Sen, A. K.; Longman, R. W. 2007-06-01 An adaptive optimal stochastic state feedback control is developed to stabilize the resistive wall mode (RWM) instability in tokamaks. The extended least square method with exponential forgetting factor and covariance resetting is used to identify the time-varying stochastic system model. A Kalman filter is used to estimate the system states. The estimated system states are passed on to an optimal state feedback controller to construct control inputs. The Kalman filter and the optimal state feedback controller are periodically redesigned online based on the identified system model. This adaptive controller can stabilize the time dependent RWM in a slowly evolving tokamak discharge. This is accomplished within a time delay of roughly four times the inverse of the growth rate for the time-invariant model used. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED581354.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED581354.pdf">Investigating the Relational Nature of Feedback Practice</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Kastberg, Signe E.; Lischka, Alyson E.; Hillman, Susan L. 2017-01-01 At the crossroads of our prior research on prospective teachers' feedback to mathematics-learners and our mathematics teacher educator feedback practices, we study written feedback as part of relational practice. Using self-study methodology and an analysis of our narratives and conversations about written feedback, we identified factors that… </li> <li> <a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/EJ1093774.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/EJ1093774.pdf">Learners' Interpersonal Beliefs and Generated Feedback in an Online Role-Playing Peer-Feedback Activity: An Exploratory Study</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Ching, Yu-Hui; Hsu, Yu-Chang 2016-01-01 Peer feedback affords interaction and critical thinking opportunities for learners in online courses. However, various factors prevent learners from taking advantage of these promising benefits. This study explored learners' perceptions of the interpersonal factors in a role-playing peer-feedback activity, and examined the types of peer feedback… </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMGC23F..04C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMGC23F..04C">Variance decomposition shows the importance of human-climate feedbacks in the Earth system</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Calvin, K. V.; Bond-Lamberty, B. P.; Jones, A. D.; Shi, X.; Di Vittorio, A. V.; Thornton, P. E. 2017-12-01 The human and Earth systems are intricately linked: climate influences agricultural production, renewable energy potential, and water availability, for example, while anthropogenic emissions from industry and land use change alter temperature and precipitation. Such feedbacks have the potential to significantly alter future climate change. Current climate change projections contain significant uncertainties, however, and because Earth System Models do not generally include dynamic human (demography, economy, energy, water, land use) components, little is known about how climate feedbacks contribute to that uncertainty. Here we use variance decomposition of a novel coupled human-earth system model to show that the influence of human-climate feedbacks can be as large as 17% of the total variance in the near term for global mean temperature rise, and 11% in the long term for cropland area. The near-term contribution of energy and land use feedbacks to the climate on global mean temperature rise is as large as that from model internal variability, a factor typically considered in modeling studies. Conversely, the contribution of climate feedbacks to cropland extent, while non-negligible, is less than that from socioeconomics, policy, or model. Previous assessments have largely excluded these feedbacks, with the climate community focusing on uncertainty due to internal variability, scenario, and model and the integrated assessment community focusing on uncertainty due to socioeconomics, technology, policy, and model. Our results set the stage for a new generation of models and hypothesis testing to determine when and how bidirectional feedbacks between human and Earth systems should be considered in future assessments of climate change. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.3281W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.3281W">Vegetation-climate feedback causes reduced precipitation in CMIP5 regional Earth system model simulation over Africa</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Wu, Minchao; Smith, Benjamin; Schurgers, Guy; Lindström, Joe; Rummukainen, Markku; Samuelsson, Patrick 2013-04-01 Terrestrial ecosystems have been demonstrated to play a significant role within the climate system, amplifying or dampening climate change via biogeophysical and biogeochemical exchange with the atmosphere and vice versa (Cox et al. 2000; Betts et al. 2004). Africa is particularly vulnerable to climate change and studies of vegetation-climate feedback mechanisms on Africa are still limited. Our study is the first application of A coupled Earth system model at regional scale and resolution over Africa. We applied a coupled regional climate-vegetation model, RCA-GUESS (Smith et al. 2011), over the CORDEX Africa domain, forced by boundary conditions from a CanESM2 CMIP5 simulation under the RCP8.5 future climate scenario. The simulations were from 1961 to 2100 and covered the African continent at a horizontal grid spacing of 0.44°. RCA-GUESS simulates changes in the phenology, productivity, relative cover and population structure of up to eight plant function types (PFTs) in response to forcing from the climate part of the model. These vegetation changes feedback to simulated climate through dynamic adjustments in surface energy fluxes and surface properties. Changes in the net ecosystem-atmosphere carbon flux and its components net primary production (NPP), heterotrophic respiration and emissions from biomass burning were also simulated but do not feedback to climate in our model. Constant land cover was assumed. We compared simulations with and without vegetation feedback switched "on" to assess the influence of vegetation-climate feedback on simulated climate, vegetation and ecosystem carbon cycling. Both positive and negative warming feedbacks were identified in different parts of Africa. In the Sahel savannah zone near 15°N, reduced vegetation cover and productivity, and mortality caused by a deterioration of soil water conditions led to a positive warming feedback mediated by decreased evapotranspiration and increased sensible heat flux between vegetation and </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JMS...180...49K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JMS...180...49K">Positive and negative feedback loops in nutrient phytoplankton interactions related to climate dynamics factors in a shallow temperate estuary (Vistula Lagoon, southern Baltic)</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Kruk, Marek; Kobos, Justyna; Nawrocka, Lidia; Parszuto, Katarzyna 2018-04-01 This study aims to demonstrate that factors associated with climate dynamics, such as temperature and wind, affect the ecosystem of the shallow Vistula Lagoon in the southern Baltic and cause nutrient forms phytoplankton interactions: the growth of biomass and constraints of it. This occurs through a network of direct and indirect relationships between environmental and phytoplankton factors, including interactions of positive and negative feedback loops. Path analysis supported by structural equation modeling (SEM) was used to test hypotheses regarding the impact of climate factors on algal assemblages. Increased phytoplankton biomass was affected directly by water temperature and salinity, while the wind speed effect was indirect as it resulted in increased concentrations of suspended solids (SS) in the water column. Simultaneously, the concentration of SS in the water was positively correlated with particulate organic carbon (POC), particulate nitrogen (PN), and particulate phosphorus (PP), and was negatively correlated with the total nitrogen to phosphorus (N:P) ratio. Particulate forms of C, N, and phosphorus (P), concentrations of soluble reactive phosphorus (SRP) and nitrate and nitrite nitrogen (NO3-N + NO2-N), and ratios of the total N:P and DIN:SRP, all indirectly effected Cyanobacteria C concentrations. These processes influence other phytoplankton groups (Chlorophyta, Bacillariophyceae and the picophytoplankton fraction). Increased levels of SRP associated with organic matter (POC), which stemmed from reduced DIN:SRP ratios, contributed to increased Cyanoprokaryota and picophytoplankton C concentrations, which created a positive feedback loop. However, a simultaneous reduction in the total N:P ratio could have inhibited increases in the biomass of these assemblages by limiting N, which likely formed a negative feedback loop. The study indicates that the nutrients-phytoplankton feedback loop phenomenon can intensify eutrophication in a temperate lagoon </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1360790-evaluating-strength-land-atmosphere-moisture-feedback-earth-system-models-using-satellite-observations','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1360790-evaluating-strength-land-atmosphere-moisture-feedback-earth-system-models-using-satellite-observations">Evaluating the strength of the land$-$atmosphere moisture feedback in Earth system models using satellite observations</a> <a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a> Levine, Paul A.; Randerson, James T.; Swenson, Sean C.; ... 2016-12-09 The relationship between terrestrial water storage (TWS) and atmospheric processes has important implications for predictability of climatic extremes and projection of future climate change. In places where moisture availability limits evapotranspiration (ET), variability in TWS has the potential to influence surface energy fluxes and atmospheric conditions. Where atmospheric conditions, in turn, influence moisture availability, a full feedback loop exists. Here we developed a novel approach for measuring the strength of both components of this feedback loop, i.e., the forcing of the atmosphere by variability in TWS and the response of TWS to atmospheric variability, using satellite observations of TWS, precipitation,more » solar radiation, and vapor pressure deficit during 2002–2014. Our approach defines metrics to quantify the relationship between TWS anomalies and climate globally on a seasonal to interannual timescale. Metrics derived from the satellite data were used to evaluate the strength of the feedback loop in 38 members of the Community Earth System Model (CESM) Large Ensemble (LENS) and in six models that contributed simulations to phase 5 of the Coupled Model Intercomparison Project (CMIP5). We found that both forcing and response limbs of the feedback loop in LENS were stronger than in the satellite observations in tropical and temperate regions. Feedbacks in the selected CMIP5 models were not as strong as those found in LENS, but were still generally stronger than those estimated from the satellite measurements. Consistent with previous studies conducted across different spatial and temporal scales, our analysis suggests that models may overestimate the strength of the feedbacks between the land surface and the atmosphere. Lastly, we describe several possible mechanisms that may contribute to this bias, and discuss pathways through which models may overestimate ET or overestimate the sensitivity of ET to TWS.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhyA..471..436G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhyA..471..436G">An improved car-following model with multiple preceding cars' velocity fluctuation feedback</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Guo, Lantian; Zhao, Xiangmo; Yu, Shaowei; Li, Xiuhai; Shi, Zhongke 2017-04-01 In order to explore and evaluate the effects of velocity variation trend of multiple preceding cars used in the Cooperative Adaptive Cruise Control (CACC) strategy on the dynamic characteristic, fuel economy and emission of the corresponding traffic flow, we conduct a study as follows: firstly, with the real-time car-following (CF) data, the close relationship between multiple preceding cars' velocity fluctuation feedback and the host car's behaviors is explored, the evaluation results clearly show that multiple preceding cars' velocity fluctuation with different time window-width are highly correlated to the host car's acceleration/deceleration. Then, a microscopic traffic flow model is proposed to evaluate the effects of multiple preceding cars' velocity fluctuation feedback in the CACC strategy on the traffic flow evolution process. Finally, numerical simulations on fuel economy and exhaust emission of the traffic flow are also implemented by utilizing VT-micro model. Simulation results prove that considering multiple preceding cars' velocity fluctuation feedback in the control strategy of the CACC system can improve roadway traffic mobility, fuel economy and exhaust emission performance. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25776225','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25776225">Feedback-giving behaviour in performance evaluations during clinical clerkships.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Bok, Harold G J; Jaarsma, Debbie A D C; Spruijt, Annemarie; Van Beukelen, Peter; Van Der Vleuten, Cees P M; Teunissen, Pim W 2016-01-01 Narrative feedback documented in performance evaluations by the teacher, i.e. the clinical supervisor, is generally accepted to be essential for workplace learning. Many studies have examined factors of influence on the usage of mini-clinical evaluation exercise (mini-CEX) instruments and provision of feedback, but little is known about how these factors influence teachers' feedback-giving behaviour. In this study, we investigated teachers' use of mini-CEX in performance evaluations to provide narrative feedback in undergraduate clinical training. We designed an exploratory qualitative study using an interpretive approach. Focusing on the usage of mini-CEX instruments in clinical training, we conducted semi-structured interviews to explore teachers' perceptions. Between February and June 2013, we conducted interviews with 14 clinicians participated as teachers during undergraduate clinical clerkships. Informed by concepts from the literature, we coded interview transcripts and iteratively reduced and displayed data using template analysis. We identified three main themes of interrelated factors that influenced teachers' practice with regard to mini-CEX instruments: teacher-related factors; teacher-student interaction-related factors, and teacher-context interaction-related factors. Four issues (direct observation, relationship between teacher and student, verbal versus written feedback, formative versus summative purposes) that are pertinent to workplace-based performance evaluations were presented to clarify how different factors interact with each other and influence teachers' feedback-giving behaviour. Embedding performance observation in clinical practice and establishing trustworthy teacher-student relationships in more longitudinal clinical clerkships were considered important in creating a learning environment that supports and facilitates the feedback exchange. Teachers' feedback-giving behaviour within the clinical context results from the interaction </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27099976','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27099976">The importance and acceptability of general and maladaptive personality trait computerized assessment feedback.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Lengel, Gregory J; Mullins-Sweatt, Stephanie N 2017-01-01 Personality traits are a useful component of clinical assessment, and have been associated with positive and negative life outcomes. Assessment of both general and maladaptive personality traits may be beneficial practice, as they may complement each other to comprehensively and accurately describe one's personality. Notably, personal preferences regarding assessment feedback have not been studied. The current study examined the acceptability of personality assessment feedback from the perspective of the examinee. Treatment-seeking participants from a university (n = 72) and Amazon.com MTurk (n = 101) completed measures of the 5-factor model and the DSM-5 alternative model of personality disorder, and were then provided feedback on their general and maladaptive personality traits. Individuals then provided feedback on which aspects they found most useful. Results demonstrated strong participant agreement that the personality trait feedback was accurate and relevant. (PsycINFO Database Record (c) 2016 APA, all rights reserved). </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27832321','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27832321">A mathematical analysis of rebound in a target-mediated drug disposition model: II. With feedback.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Aston, Philip J; Derks, Gianne; Agoram, Balaji M; van der Graaf, Piet H 2017-07-01 We consider the possibility of free receptor (antigen/cytokine) levels rebounding to higher than the baseline level after the application of an antibody drug using a target-mediated drug disposition model. It is assumed that the receptor synthesis rate experiences homeostatic feedback from the receptor levels. It is shown for a very fast feedback response, that the occurrence of rebound is determined by the ratio of the elimination rates, in a very similar way as for no feedback. However, for a slow feedback response, there will always be rebound. This result is illustrated with an example involving the drug efalizumab for patients with psoriasis. It is shown that slow feedback can be a plausible explanation for the observed rebound in this example. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17381264','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17381264">Dynamics of nonlinear feedback control.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Snippe, H P; van Hateren, J H 2007-05-01 Feedback control in neural systems is ubiquitous. Here we study the mathematics of nonlinear feedback control. We compare models in which the input is multiplied by a dynamic gain (multiplicative control) with models in which the input is divided by a dynamic attenuation (divisive control). The gain signal (resp. the attenuation signal) is obtained through a concatenation of an instantaneous nonlinearity and a linear low-pass filter operating on the output of the feedback loop. For input steps, the dynamics of gain and attenuation can be very different, depending on the mathematical form of the nonlinearity and the ordering of the nonlinearity and the filtering in the feedback loop. Further, the dynamics of feedback control can be strongly asymmetrical for increment versus decrement steps of the input. Nevertheless, for each of the models studied, the nonlinearity in the feedback loop can be chosen such that immediately after an input step, the dynamics of feedback control is symmetric with respect to increments versus decrements. Finally, we study the dynamics of the output of the control loops and find conditions under which overshoots and undershoots of the output relative to the steady-state output occur when the models are stimulated with low-pass filtered steps. For small steps at the input, overshoots and undershoots of the output do not occur when the filtering in the control path is faster than the low-pass filtering at the input. For large steps at the input, however, results depend on the model, and for some of the models, multiple overshoots and undershoots can occur even with a fast control path. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013MNRAS.430.1901H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013MNRAS.430.1901H">Star formation in galaxy mergers with realistic models of stellar feedback and the interstellar medium</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Hopkins, Philip F.; Cox, Thomas J.; Hernquist, Lars; Narayanan, Desika; Hayward, Christopher C.; Murray, Norman 2013-04-01 We use hydrodynamic simulations with detailed, explicit models for stellar feedback to study galaxy mergers. These high-resolution (˜1 pc) simulations follow the formation and destruction of individual giant molecular clouds (GMC) and star clusters. We find that the final starburst is dominated by in situ star formation, fuelled by gas which flows inwards due to global torques. The resulting high gas density results in rapid star formation. The gas is self-gravitating, and forms massive (≲1010 M⊙) GMC and subsequently super star clusters (with masses up to 108 M⊙). However, in contrast to some recent simulations, the bulk of new stars which eventually form the central bulge are not born in super-clusters which then sink to the centre of the galaxy. This is because feedback efficiently disperses GMC after they turn several per cent of their mass into stars. In other words, most of the mass that reaches the nucleus does so in the form of gas. The Kennicutt-Schmidt law emerges naturally as a consequence of feedback balancing gravitational collapse, independent of the small-scale star formation microphysics. The same mechanisms that drive this relation in isolated galaxies, in particular radiation pressure from infrared photons, extend, with no fine-tuning, over seven decades in star formation rate (SFR) to regulate star formation in the most extreme starburst systems with densities ≳104 M⊙ pc-2. This feedback also drives super-winds with large mass-loss rates; however, a significant fraction of the wind material falls back on to the discs at later times, leading to higher post-starburst SFRs in the presence of stellar feedback. This suggests that strong active galactic nucleus feedback may be required to explain the sharp cut-offs in SFR that are observed in post-merger galaxies. We compare the results to those from simulations with no explicit resolution of GMC or feedback [`effective equation-of-state' (EOS) models]. We find that global galaxy properties </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4593861','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4593861">A model-based approach to predict muscle synergies using optimization: application to feedback control</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Sharif Razavian, Reza; Mehrabi, Naser; McPhee, John 2015-01-01 This paper presents a new model-based method to define muscle synergies. Unlike the conventional factorization approach, which extracts synergies from electromyographic data, the proposed method employs a biomechanical model and formally defines the synergies as the solution of an optimal control problem. As a result, the number of required synergies is directly related to the dimensions of the operational space. The estimated synergies are posture-dependent, which correlate well with the results of standard factorization methods. Two examples are used to showcase this method: a two-dimensional forearm model, and a three-dimensional driver arm model. It has been shown here that the synergies need to be task-specific (i.e., they are defined for the specific operational spaces: the elbow angle and the steering wheel angle in the two systems). This functional definition of synergies results in a low-dimensional control space, in which every force in the operational space is accurately created by a unique combination of synergies. As such, there is no need for extra criteria (e.g., minimizing effort) in the process of motion control. This approach is motivated by the need for fast and bio-plausible feedback control of musculoskeletal systems, and can have important implications in engineering, motor control, and biomechanics. PMID:26500530 </li> <li> <a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940031405','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940031405">Nonlinear feedback model attitude control using CCD in magnetic suspension system</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Lin, CHIN-E.; Hou, Ann-San 1994-01-01 A model attitude control system for a CCD camera magnetic suspension system is studied in this paper. In a recent work, a position and attitude sensing method was proposed. From this result, model position and attitude of a magnetic suspension system can be detected by generating digital outputs. Based on this achievement, a control system design using nonlinear feedback techniques for magnetic suspended model attitude control is proposed. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED040484.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED040484.pdf">Feedback and Sentence Learning.</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Guthrie, John T. The theoretical functions of external feedback in SR and closed loop models of verbal learning are presented. Contradictory predictions from the models are tested with a three by three factorial experiment including three types of feedback and three amounts of rehearsal. There were 90 adult students run individually and they were required to learn… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29215021','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29215021">An improved ENSO simulation by representing chlorophyll-induced climate feedback in the NCAR Community Earth System Model.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Kang, Xianbiao; Zhang, Rong-Hua; Gao, Chuan; Zhu, Jieshun 2017-12-07 The El Niño-Southern oscillation (ENSO) simulated in the Community Earth System Model of the National Center for Atmospheric Research (NCAR CESM) is much stronger than in reality. Here, satellite data are used to derive a statistical relationship between interannual variations in oceanic chlorophyll (CHL) and sea surface temperature (SST), which is then incorporated into the CESM to represent oceanic chlorophyll -induced climate feedback in the tropical Pacific. Numerical runs with and without the feedback (referred to as feedback and non-feedback runs) are performed and compared with each other. The ENSO amplitude simulated in the feedback run is more accurate than that in the non-feedback run; quantitatively, the Niño3 SST index is reduced by 35% when the feedback is included. The underlying processes are analyzed and the results show that interannual CHL anomalies exert a systematic modulating effect on the solar radiation penetrating into the subsurface layers, which induces differential heating in the upper ocean that affects vertical mixing and thus SST. The statistical modeling approach proposed in this work offers an effective and economical way for improving climate simulations. </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active">7</li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_8" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active">8</li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="141"> <li> <a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA475344','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA475344">Control Theory Perspective of Effects-Based Thinking and Operations: Modelling Operations as a Feedback Control System</a> <a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a> 2007-11-01 Control Theory Perspective of Effects-Based Thinking and Operations Modelling “Operations” as a Feedback Control System Philip S. E... Theory Perspective of Effects-Based Thinking and Operations Modelling “Operations” as a Feedback Control System Philip S. E. Farrell...Abstract This paper explores operations that involve effects-based thinking (EBT) using Control Theory techniques in order to highlight the concept’s </li> <li> <a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19900020491','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19900020491">Modeling and sensory feedback control for space manipulators</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Masutani, Yasuhiro; Miyazaki, Fumio; Arimoto, Suguru 1989-01-01 The positioning control problem of the endtip of space manipulators whose base are uncontrolled is examined. In such a case, the conventional control method for industrial robots based on a local feedback at each joint is not applicable, because a solution of the joint displacements that satisfies a given position and orientation of the endtip is not decided uniquely. A sensory feedback control scheme for space manipulators based on an artificial potential defined in a task-oriented coordinates is proposed. Using this scheme, the controller can easily determine the input torque of each joint from the data of an external sensor such as a visual device. Since the external sensor is mounted on the unfixed base, the manipulator must track the moving image of the target in sensor coordinates. Moreover the dynamics of the base and the manipulator are interactive. However, the endtip is proven to asymptotically approach the stationary target in an inertial coordinate frame by the Liapunov's method. Finally results of computer simulation for a 6-link space manipulator model show the effectiveness of the proposed scheme. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMAE33A0435D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMAE33A0435D">Combining lightning leader and relativistic feedback discharge models of terrestrial gamma-ray flashes</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Dwyer, J. R. 2016-12-01 Lightning leader models of terrestrial gamma-ray flashes (TGFs) are based on the observations that leaders emit bursts of hard x-rays. These x-rays are thought to be generated by runaway electrons created in the high-field regions associated with the leader tips and/or streamers heads. Inside a thunderstorm, it has been proposed that these runaway electrons may experience additional relativistic runaway electron avalanche (RREA) multiplication, increasing the number and the average energy of the electrons, and possibly resulting in a TGF. When modeling TGFs it is important to include the discharge currents resulting from the ionization produced by the runaway electrons, since these currents may alter the electric fields and affect the TGF. In addition, relativistic feedback effects, caused by backward propagating positrons and backscattered x-rays, need to be included, since relativistic feedback limits the size of the electric field and the amount of a RREA multiplication that may occur. In this presentation, a lightning leader model of terrestrial gamma-ray flashes that includes the effects of the discharge currents and relativistic feedback will be described and compared with observations. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001AGUSM...B52B01M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001AGUSM...B52B01M">Short- and Long-Term Feedbacks on Vegetation Water Use: Unifying Evidence from Observations and Modeling</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Mackay, D. S. 2001-05-01 Recent efforts to measure and model the interacting influences of climate, soil, and vegetation on soil water and nutrient dynamics have identified numerous important feedbacks that produce nonlinear responses. In particular, plant physiological factors that control rates of transpiration respond to soil water deficits and vapor pressure deficits (VPD) in the short-term, and to climate, nutrient cycling and disturbance in the long-term. The starting point of this presentation is the observation that in many systems, in particular forest ecosystems, conservative water use emerges as a result of short-term closure of stomata in response to high evaporative demand, and long-term vegetative canopy development under nutrient limiting conditions. Evidence for important short-term controls is presented from sap flux measurements of stand transpiration, remote sensing, and modeling of transpiration through a combination of physically-based modeling and Monte Carlo analysis. A common result is a strong association between stomatal conductance (gs) and the negative evaporative gain (∂ gs/∂ VPD) associated with the sensitivity of stomatal closure to rates of water loss. The importance of this association from the standpoint of modeling transpiration depends on the degree of canopy-atmosphere coupling. This suggests possible simplifications to future canopy component models for use in watershed and larger-scale hydrologic models for short-term processes. However, further results are presented from theoretical modeling, which suggest that feedbacks between hydrology and vegetation in current long-term (inter-annual to century) models may be too simple, as they do not capture the spatially variable nature of slow nutrient cycling in response to soil water dynamics and site history. Memory effects in the soil nutrient pools can leave lasting effects on more rapid processes associated with soil, vegetation, atmosphere coupling. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5342018','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5342018">CoGAPS matrix factorization algorithm identifies transcriptional changes in AP-2alpha target genes in feedback from therapeutic inhibition of the EGFR network</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Thakar, Manjusha; Howard, Jason D.; Kagohara, Luciane T.; Krigsfeld, Gabriel; Ranaweera, Ruchira S.; Hughes, Robert M.; Perez, Jimena; Jones, Siân; Favorov, Alexander V.; Carey, Jacob; Stein-O'Brien, Genevieve; Gaykalova, Daria A.; Ochs, Michael F.; Chung, Christine H. 2016-01-01 Patients with oncogene driven tumors are treated with targeted therapeutics including EGFR inhibitors. Genomic data from The Cancer Genome Atlas (TCGA) demonstrates molecular alterations to EGFR, MAPK, and PI3K pathways in previously untreated tumors. Therefore, this study uses bioinformatics algorithms to delineate interactions resulting from EGFR inhibitor use in cancer cells with these genetic alterations. We modify the HaCaT keratinocyte cell line model to simulate cancer cells with constitutive activation of EGFR, HRAS, and PI3K in a controlled genetic background. We then measure gene expression after treating modified HaCaT cells with gefitinib, afatinib, and cetuximab. The CoGAPS algorithm distinguishes a gene expression signature associated with the anticipated silencing of the EGFR network. It also infers a feedback signature with EGFR gene expression itself increasing in cells that are responsive to EGFR inhibitors. This feedback signature has increased expression of several growth factor receptors regulated by the AP-2 family of transcription factors. The gene expression signatures for AP-2alpha are further correlated with sensitivity to cetuximab treatment in HNSCC cell lines and changes in EGFR expression in HNSCC tumors with low CDKN2A gene expression. In addition, the AP-2alpha gene expression signatures are also associated with inhibition of MEK, PI3K, and mTOR pathways in the Library of Integrated Network-Based Cellular Signatures (LINCS) data. These results suggest that AP-2 transcription factors are activated as feedback from EGFR network inhibition and may mediate EGFR inhibitor resistance. PMID:27650546 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29243052','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29243052">Motivation and emotion predict medical students' attention to computer-based feedback.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Naismith, Laura M; Lajoie, Susanne P 2017-12-14 Students cannot learn from feedback unless they pay attention to it. This study investigated relationships between the personal factors of achievement goal orientations, achievement emotions, and attention to feedback in BioWorld, a computer environment for learning clinical reasoning. Novice medical students (N = 28) completed questionnaires to measure their achievement goal orientations and then thought aloud while solving three endocrinology patient cases and reviewing corresponding expert solutions. Questionnaires administered after each case measured participants' experiences of five feedback emotions: pride, relief, joy, shame, and anger. Attention to individual text segments of the expert solutions was modelled using logistic regression and the method of generalized estimating equations. Participants did not attend to all of the feedback that was available to them. Performance-avoidance goals and shame positively predicted attention to feedback, and performance-approach goals and relief negatively predicted attention to feedback. Aspects of how the feedback was displayed also influenced participants' attention. Findings are discussed in terms of their implications for educational theory as well as the design and use of computer learning environments in medical education. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=c&pg=7&id=EJ1120586','ERIC'); return false;" href="https://eric.ed.gov/?q=c&pg=7&id=EJ1120586">Computational Model of a Positive BDNF Feedback Loop in Hippocampal Neurons Following Inhibitory Avoidance Training</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Zhang, Yili; Smolen, Paul; Alberini, Cristina M.; Baxter, Douglas A.; Byrne, John H. 2016-01-01 Inhibitory avoidance (IA) training in rodents initiates a molecular cascade within hippocampal neurons. This cascade contributes to the transition of short- to long-term memory (i.e., consolidation). Here, a differential equation-based model was developed to describe a positive feedback loop within this molecular cascade. The feedback loop begins… </li> <li> <a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20090040059','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20090040059">Simple Optoelectronic Feedback in Microwave Oscillators</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Maleki, Lute; Iltchenko, Vladimir 2009-01-01 A proposed method of stabilizing microwave and millimeter-wave oscillators calls for the use of feedback in optoelectronic delay lines characterized by high values of the resonance quality factor (Q). The method would extend the applicability of optoelectronic feedback beyond the previously reported class of optoelectronic oscillators that comprise two-port electronic amplifiers in closed loops with high-Q feedback circuits. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26438278','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26438278">The impact of parametrized convection on cloud feedback.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Webb, Mark J; Lock, Adrian P; Bretherton, Christopher S; Bony, Sandrine; Cole, Jason N S; Idelkadi, Abderrahmane; Kang, Sarah M; Koshiro, Tsuyoshi; Kawai, Hideaki; Ogura, Tomoo; Roehrig, Romain; Shin, Yechul; Mauritsen, Thorsten; Sherwood, Steven C; Vial, Jessica; Watanabe, Masahiro; Woelfle, Matthew D; Zhao, Ming 2015-11-13 We investigate the sensitivity of cloud feedbacks to the use of convective parametrizations by repeating the CMIP5/CFMIP-2 AMIP/AMIP + 4K uniform sea surface temperature perturbation experiments with 10 climate models which have had their convective parametrizations turned off. Previous studies have suggested that differences between parametrized convection schemes are a leading source of inter-model spread in cloud feedbacks. We find however that 'ConvOff' models with convection switched off have a similar overall range of cloud feedbacks compared with the standard configurations. Furthermore, applying a simple bias correction method to allow for differences in present-day global cloud radiative effects substantially reduces the differences between the cloud feedbacks with and without parametrized convection in the individual models. We conclude that, while parametrized convection influences the strength of the cloud feedbacks substantially in some models, other processes must also contribute substantially to the overall inter-model spread. The positive shortwave cloud feedbacks seen in the models in subtropical regimes associated with shallow clouds are still present in the ConvOff experiments. Inter-model spread in shortwave cloud feedback increases slightly in regimes associated with trade cumulus in the ConvOff experiments but is quite similar in the most stable subtropical regimes associated with stratocumulus clouds. Inter-model spread in longwave cloud feedbacks in strongly precipitating regions of the tropics is substantially reduced in the ConvOff experiments however, indicating a considerable local contribution from differences in the details of convective parametrizations. In both standard and ConvOff experiments, models with less mid-level cloud and less moist static energy near the top of the boundary layer tend to have more positive tropical cloud feedbacks. The role of non-convective processes in contributing to inter-model spread in cloud feedback </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4608036','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4608036">The impact of parametrized convection on cloud feedback</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Webb, Mark J.; Lock, Adrian P.; Bretherton, Christopher S.; Bony, Sandrine; Cole, Jason N. S.; Idelkadi, Abderrahmane; Kang, Sarah M.; Koshiro, Tsuyoshi; Kawai, Hideaki; Ogura, Tomoo; Roehrig, Romain; Shin, Yechul; Mauritsen, Thorsten; Sherwood, Steven C.; Vial, Jessica; Watanabe, Masahiro; Woelfle, Matthew D.; Zhao, Ming 2015-01-01 We investigate the sensitivity of cloud feedbacks to the use of convective parametrizations by repeating the CMIP5/CFMIP-2 AMIP/AMIP + 4K uniform sea surface temperature perturbation experiments with 10 climate models which have had their convective parametrizations turned off. Previous studies have suggested that differences between parametrized convection schemes are a leading source of inter-model spread in cloud feedbacks. We find however that ‘ConvOff’ models with convection switched off have a similar overall range of cloud feedbacks compared with the standard configurations. Furthermore, applying a simple bias correction method to allow for differences in present-day global cloud radiative effects substantially reduces the differences between the cloud feedbacks with and without parametrized convection in the individual models. We conclude that, while parametrized convection influences the strength of the cloud feedbacks substantially in some models, other processes must also contribute substantially to the overall inter-model spread. The positive shortwave cloud feedbacks seen in the models in subtropical regimes associated with shallow clouds are still present in the ConvOff experiments. Inter-model spread in shortwave cloud feedback increases slightly in regimes associated with trade cumulus in the ConvOff experiments but is quite similar in the most stable subtropical regimes associated with stratocumulus clouds. Inter-model spread in longwave cloud feedbacks in strongly precipitating regions of the tropics is substantially reduced in the ConvOff experiments however, indicating a considerable local contribution from differences in the details of convective parametrizations. In both standard and ConvOff experiments, models with less mid-level cloud and less moist static energy near the top of the boundary layer tend to have more positive tropical cloud feedbacks. The role of non-convective processes in contributing to inter-model spread in cloud </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24151809','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24151809">Feedback in clinical education, part II: Approved clinical instructor and student perceptions of and influences on feedback.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Nottingham, Sara; Henning, Jolene 2014-01-01 Approved Clinical Instructors (ACIs; now known as preceptors) are expected to provide feedback to athletic training students (ATSs) during clinical education experiences. Researchers in other fields have found that clinical instructors and students often have different perceptions of actual and ideal feedback and that several factors may influence the feedback exchanges between instructors and students. However, understanding of these issues in athletic training education is minimal. To investigate the current characteristics and perceptions of and the influences on feedback exchanges between ATSs and ACIs. Qualitative study. One entry-level master's degree program accredited by the Commission on Accreditation of Athletic Training Education. Four ACIs and 4 second-year ATSs. Individual, semistructured interviews were conducted with participants and integrated with field notes and observations for analysis. We used the constant comparative approach to inductively analyze data and develop codes and categories. Member checking, triangulation, and peer debriefing were used to promote trustworthiness of the study. Participants described that feedback plays an important role in clinical education and has several purposes related to improving performance. The ACIs and ATSs also discussed several preferred characteristics of feedback. Participants identified 4 main influences on their feedback exchanges, including the ACI, the ATS, personalities, and the learning environment. The ACIs and ATSs had similar perceptions of ideal feedback in addition to the actual feedback that was provided during their clinical education experiences. Most of the preferences for feedback were aligned with recommendations in the literature, suggesting that existing research findings are applicable to athletic training clinical education. Several factors influenced the feedback exchanges between ACIs and ATSs, which clinical education coordinators should consider when selecting clinical sites </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011WRR....4712520E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011WRR....4712520E">Feedback loops and temporal misalignment in component-based hydrologic modeling</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Elag, Mostafa M.; Goodall, Jonathan L.; Castronova, Anthony M. 2011-12-01 In component-based modeling, a complex system is represented as a series of loosely integrated components with defined interfaces and data exchanges that allow the components to be coupled together through shared boundary conditions. Although the component-based paradigm is commonly used in software engineering, it has only recently been applied for modeling hydrologic and earth systems. As a result, research is needed to test and verify the applicability of the approach for modeling hydrologic systems. The objective of this work was therefore to investigate two aspects of using component-based software architecture for hydrologic modeling: (1) simulation of feedback loops between components that share a boundary condition and (2) data transfers between temporally misaligned model components. We investigated these topics using a simple case study where diffusion of mass is modeled across a water-sediment interface. We simulated the multimedia system using two model components, one for the water and one for the sediment, coupled using the Open Modeling Interface (OpenMI) standard. The results were compared with a more conventional numerical approach for solving the system where the domain is represented by a single multidimensional array. Results showed that the component-based approach was able to produce the same results obtained with the more conventional numerical approach. When the two components were temporally misaligned, we explored the use of different interpolation schemes to minimize mass balance error within the coupled system. The outcome of this work provides evidence that component-based modeling can be used to simulate complicated feedback loops between systems and guidance as to how different interpolation schemes minimize mass balance error introduced when components are temporally misaligned. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=Shunji&id=EJ571982','ERIC'); return false;" href="https://eric.ed.gov/?q=Shunji&id=EJ571982">The Role of Implicit Negative Feedback in SLA: Models and Recasts in Japanese and Spanish.</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Long, Michael; Inagaki, Shunji; Ortega, Lourdes 1998-01-01 Two experiments were conducted to assess relative utility of models and recasts in second-language (L2) Japanese and Spanish. Using pretest, posttest, control group design, each study provided evidence of adults' ability to learn from implicit negative feedback; in one case, support for notion that reactive implicit negative feedback can be more… </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.B54F..01M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.B54F..01M">Evaluation of Offline Models Used to Simulate Components of the Permafrost Carbon Feedback: Experience from the Permafrost Carbon Network Model Integration Group</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> McGuire, A. D. 2016-12-01 The Model Integration Group of the Permafrost Carbon Network (see http://www.permafrostcarbon.org/) has conducted studies to evaluate the sensitivity of offline terrestrial permafrost and carbon models to both historical and projected climate change. These studies indicate that there is a wide range of (1) initial states permafrost extend and carbon stocks simulated by these models and (2) responses of permafrost extent and carbon stocks to both historical and projected climate change. In this study, we synthesize what has been learned about the variability in initial states among models and the driving factors that contribute to variability in the sensitivity of responses. We conclude the talk with a discussion of efforts needed by (1) the modeling community to standardize structural representation of permafrost and carbon dynamics among models that are used to evaluate the permafrost carbon feedback and (2) the modeling and observational communities to jointly develop data sets and methodologies to more effectively benchmark models. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=emotional+AND+factor+AND+definition&id=EJ1163076','ERIC'); return false;" href="https://eric.ed.gov/?q=emotional+AND+factor+AND+definition&id=EJ1163076">Interplay among Technical, Socio-Emotional and Personal Factors in Written Feedback Research</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Chong, Ivan 2018-01-01 The centrality of written feedback is clearly seen from the proliferation of research in the context of higher education. As an increasingly expanding field in research, the majority of written feedback studies have been interested in investigating the technical aspect of how feedback should be given in order to promote student learning. More… </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015IAUGA..2254732H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015IAUGA..2254732H">Star-formation and stellar feedback recipes in galaxy evolution models</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Hensler, Gerhard; Recchi, Simone; Ploeckinger, Sylvia; Kuehtreiber, Matthias; Steyrleithner, Patrick; Liu, Lei 2015-08-01 Modeling galaxy formation and evolution is critically depending on star formation (SF). Since cosmological and galaxy-scale simulations cannot resolve the spatial and density scales on which SF acts, a large variety of methods are developed and applied over the last decades. Nonetheless, we are still in the test phase how the choice of parameters affects the models and how they agree with observations.As a simple ansatz, recipes are based on power-law SF dependences on gas density as justified by gas cooling and collapse timescales. In order to prevent SF spread throughout the gas, temperature and density thresholds are also used, although gas dynamical effects, like e.g. gas infall, seem to trigger SF significantly.The formed stars influence their environment immediately by energetic and materialistic feedback. It has been experienced in numerical models that supernova typeII explosions act with a too long time delay to regulate the SF, but that winds and ionizing radiation by massive stars must be included. The implementation of feedback processes, their efficiencies and timescales, is still in an experimental state, because they depend also on the physical state of the surrounding interstellar medium (ISM).Combining a SF-gas density relation with stellar heating vs. gas cooling and taking the temperature dependence into account, we have derived an analytical expression of self-regulated SF which is free of arbitrary parameters. We have performed numerical models to study this recipe and different widely used SF criteria in both, particle and grid codes. Moreover, we compare the SF behavior between single-gas phase and multi-phase treatments of the ISM.Since dwarf galaxies (DGs) are most sensitive to environmental influences and contain only low SF rates, we explore two main affects on their models: 1. For external effects we compare SF rates of isolated and ram-pressure suffering DGs. Moreover, we find a SF enhancement in tidal-tail DGs by the compressive tidal </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15504781','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15504781">Do volunteer community-based preceptors value students' feedback?</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Dent, M Marie; Boltri, John; Okosun, Ike S 2004-11-01 A key component of educational practice is to provide feedback and evaluation to teachers and learners to improve the teaching and learning process. The purpose of this study was to determine whether volunteer community preceptors value evaluation and feedback by students as much as they value other resources or rewards. In Fall 1999, a questionnaire concerning the resources and rewards of preceptorship was mailed to 236 community preceptors affiliated with the Mercer University School of Medicine, Macon, Georgia. Preceptors were asked to rate 20 factors on a five-point Likert scale (5 = very important to 1 = not very important). The mean values were compared using t-tests. One hundred sixty-eight preceptors (71%) completed questionnaires. Preceptors rated evaluation and feedback from students significantly higher (p < .001) than all other factors (mean = 4.02, standard deviation [SD] = .87). Continuing medical education for teaching was the next most highly valued factor (mean = 3.67, SD = 1.14). Preceptors rated financial compensation the lowest (mean = 2.01, SD = 1.19) of all factors. The high rank of feedback and evaluation from students persisted across gender, specialty, length of time as a preceptor, practice location, and years practicing medicine. This study demonstrates that feedback and evaluation from students is highly valued. The knowledge that community-based preceptors highly value feedback and evaluation from students should stimulate medical school programs to provide feedback and evaluation to preceptors that will enhance the educational outcomes for both faculty and learners. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3917297','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3917297">Feedback in Clinical Education, Part II: Approved Clinical Instructor and Student Perceptions of and Influences on Feedback</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Nottingham, Sara; Henning, Jolene 2014-01-01 Context: Approved Clinical Instructors (ACIs; now known as preceptors) are expected to provide feedback to athletic training students (ATSs) during clinical education experiences. Researchers in other fields have found that clinical instructors and students often have different perceptions of actual and ideal feedback and that several factors may influence the feedback exchanges between instructors and students. However, understanding of these issues in athletic training education is minimal. Objective: To investigate the current characteristics and perceptions of and the influences on feedback exchanges between ATSs and ACIs. Design: Qualitative study. Setting: One entry-level master's degree program accredited by the Commission on Accreditation of Athletic Training Education. Patients or Other Participants: Four ACIs and 4 second-year ATSs. Data Collection and Analysis: Individual, semistructured interviews were conducted with participants and integrated with field notes and observations for analysis. We used the constant comparative approach to inductively analyze data and develop codes and categories. Member checking, triangulation, and peer debriefing were used to promote trustworthiness of the study. Results: Participants described that feedback plays an important role in clinical education and has several purposes related to improving performance. The ACIs and ATSs also discussed several preferred characteristics of feedback. Participants identified 4 main influences on their feedback exchanges, including the ACI, the ATS, personalities, and the learning environment. Conclusions: The ACIs and ATSs had similar perceptions of ideal feedback in addition to the actual feedback that was provided during their clinical education experiences. Most of the preferences for feedback were aligned with recommendations in the literature, suggesting that existing research findings are applicable to athletic training clinical education. Several factors influenced the </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ClDy...50..571Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ClDy...50..571Z">Influence of surface nudging on climatological mean and ENSO feedbacks in a coupled model</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Zhu, Jieshun; Kumar, Arun 2018-01-01 Studies have suggested that surface nudging could be an efficient way to reconstruct the subsurface ocean variability, and thus a useful method for initializing climate predictions (e.g., seasonal and decadal predictions). Surface nudging is also the basis for climate models with flux adjustments. In this study, however, some negative aspects of surface nudging on climate simulations in a coupled model are identified. Specifically, a low-resolution version of the NCEP Climate Forecast System, version 2 (CFSv2L) is used to examine the influence of nudging on simulations of climatological mean and on the coupled feedbacks during ENSO. The effect on ENSO feedbacks is diagnosed following a heat budget analysis of mixed layer temperature anomalies. Diagnostics of the climatological mean state indicates that, even though SST biases in all ocean basins, as expected, are eliminated, the fidelity of climatological precipitation, surface winds and subsurface temperature (or the thermocline depth) could be highly ocean basin dependent. This is exemplified by improvements in the climatology of these variables in the tropical Atlantic, but degradations in the tropical Pacific. Furthermore, surface nudging also distorts the dynamical feedbacks during ENSO. For example, while the thermocline feedback played a critical role during the evolution of ENSO in a free simulation, it only played a minor role in the nudged simulation. These results imply that, even though the simulation of surface temperature could be improved in a climate model with surface nudging, the physics behind might be unrealistic. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1980WRR....16..225O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1980WRR....16..225O">On a Model of a Nonlinear Feedback System for River Flow Prediction</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Ozaki, T. 1980-02-01 A nonlinear system with feedback is proposed as a dynamic model for the hydrological system, whose input is the rainfall and whose output is the discharge of river flow. Parameters and orders of the model are estimated using Akaike's information criterion. Its application to the prediction of daily discharges of Kanna River and Bird Creek is discussed. </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active">8</li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_9" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active">9</li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="161"> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28704204','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28704204">Psychometric analysis of the Swedish version of the General Medical Council's multi source feedback questionnaires.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Olsson, Jan-Eric; Wallentin, Fan Yang; Toth-Pal, Eva; Ekblad, Solvig; Bertilson, Bo Christer 2017-07-10 To determine the internal consistency and the underlying components of our translated and adapted Swedish version of the General Medical Council's multisource feedback questionnaires (GMC questionnaires) for physicians and to confirm which aspects of good medical practice the latent variable structure reflected. From October 2015 to March 2016, residents in family medicine in Sweden were invited to participate in the study and to use the Swedish version to perform self-evaluations and acquire feedback from both their patients and colleagues. The validation focused on internal consistency and construct validity. Main outcome measures were Cronbach's alpha coefficients, Principal Component Analysis, and Confirmatory Factor Analysis indices. A total of 752 completed questionnaires from patients, colleagues, and residents were analysed. Of these, 213 comprised resident self-evaluations, 336 were feedback from residents' patients, and 203 were feedback from residents' colleagues. Cronbach's alpha coefficients of the scores were 0.88 from patients, 0.93 from colleagues, and 0.84 in the self-evaluations. The Confirmatory Factor Analysis validated two models that fit the data reasonably well and reflected important aspects of good medical practice. The first model had two latent factors for patient-related items concerning empathy and consultation management, and the second model had five latent factors for colleague-related items, including knowledge and skills, attitude and approach, reflection and development, teaching, and trust. The current Swedish version seems to be a reliable and valid tool for formative assessment for resident physicians and their supervisors. This needs to be verified in larger samples. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5511742','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5511742">Psychometric analysis of the Swedish version of the General Medical Council's multi source feedback questionnaires</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Wallentin, Fan Yang; Toth-Pal, Eva; Ekblad, Solvig; Bertilson, Bo Christer 2017-01-01 Objectives To determine the internal consistency and the underlying components of our translated and adapted Swedish version of the General Medical Council's multisource feedback questionnaires (GMC questionnaires) for physicians and to confirm which aspects of good medical practice the latent variable structure reflected. Methods From October 2015 to March 2016, residents in family medicine in Sweden were invited to participate in the study and to use the Swedish version to perform self-evaluations and acquire feedback from both their patients and colleagues. The validation focused on internal consistency and construct validity. Main outcome measures were Cronbach’s alpha coefficients, Principal Component Analysis, and Confirmatory Factor Analysis indices. Results A total of 752 completed questionnaires from patients, colleagues, and residents were analysed. Of these, 213 comprised resident self-evaluations, 336 were feedback from residents’ patients, and 203 were feedback from residents’ colleagues. Cronbach’s alpha coefficients of the scores were 0.88 from patients, 0.93 from colleagues, and 0.84 in the self-evaluations. The Confirmatory Factor Analysis validated two models that fit the data reasonably well and reflected important aspects of good medical practice. The first model had two latent factors for patient-related items concerning empathy and consultation management, and the second model had five latent factors for colleague-related items, including knowledge and skills, attitude and approach, reflection and development, teaching, and trust. Conclusions The current Swedish version seems to be a reliable and valid tool for formative assessment for resident physicians and their supervisors. This needs to be verified in larger samples. PMID:28704204 </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017IJSS...48.1071R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017IJSS...48.1071R">Model-Free control performance improvement using virtual reference feedback tuning and reinforcement Q-learning</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Radac, Mircea-Bogdan; Precup, Radu-Emil; Roman, Raul-Cristian 2017-04-01 This paper proposes the combination of two model-free controller tuning techniques, namely linear virtual reference feedback tuning (VRFT) and nonlinear state-feedback Q-learning, referred to as a new mixed VRFT-Q learning approach. VRFT is first used to find stabilising feedback controller using input-output experimental data from the process in a model reference tracking setting. Reinforcement Q-learning is next applied in the same setting using input-state experimental data collected under perturbed VRFT to ensure good exploration. The Q-learning controller learned with a batch fitted Q iteration algorithm uses two neural networks, one for the Q-function estimator and one for the controller, respectively. The VRFT-Q learning approach is validated on position control of a two-degrees-of-motion open-loop stable multi input-multi output (MIMO) aerodynamic system (AS). Extensive simulations for the two independent control channels of the MIMO AS show that the Q-learning controllers clearly improve performance over the VRFT controllers. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=self+AND+verification&id=EJ874783','ERIC'); return false;" href="https://eric.ed.gov/?q=self+AND+verification&id=EJ874783">Interpersonal Congruence, Transactive Memory, and Feedback Processes: An Integrative Model of Group Learning</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> London, Manuel; Polzer, Jeffrey T.; Omoregie, Heather 2005-01-01 This article presents a multilevel model of group learning that focuses on antecedents and consequences of interpersonal congruence, transactive memory, and feedback processes. The model holds that members' self-verification motives and situational conditions (e.g., member diversity and task demands) give rise to identity negotiation behaviors… </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018E3SWC..3804017G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018E3SWC..3804017G">Modeling and Simulation of Hydropower Station Diversion System's characteristic line method by introducing water head to flow feedback</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Guangwen, Xu; Xi, Li; Ze, Yao 2018-06-01 To solve the damping problem of water hammer wave in the modeling method of water diversion system of hydropower station, this paper introduces the feedback regulation technology from head to flow, that is: A fixed water head is taken out for flow feedback, and the following conclusions are obtained through modeling and simulation. Adjusting the feedback coefficient F of the water head to the flow rate can change the damping characteristic of the system, which can simulate the attenuation process of the water shock wave in the true water diversion pipeline. Even if a small feedback coefficient is introduced, the damping effect of the system is very obvious, but it has little effect on the amplitude of the first water shock wave after the transition process. Therefore, it is feasible and reasonable to introduce water head to flow rate feedback coefficient F in hydraulic turbine diversion system. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.B23K0151G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.B23K0151G">Characterizing Feedback Control Mechanisms in Nonlinear Microbial Models of Soil Organic Matter Decomposition by Stability Analysis</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Georgiou, K.; Tang, J.; Riley, W. J.; Torn, M. S. 2014-12-01 Soil organic matter (SOM) decomposition is regulated by biotic and abiotic processes. Feedback interactions between such processes may act to dampen oscillatory responses to perturbations from equilibrium. Indeed, although biological oscillations have been observed in small-scale laboratory incubations, the overlying behavior at the plot-scale exhibits a relatively stable response to disturbances in input rates and temperature. Recent studies have demonstrated the ability of microbial models to capture nonlinear feedbacks in SOM decomposition that linear Century-type models are unable to reproduce, such as soil priming in response to increased carbon input. However, these microbial models often exhibit strong oscillatory behavior that is deemed unrealistic. The inherently nonlinear dynamics of SOM decomposition have important implications for global climate-carbon and carbon-concentration feedbacks. It is therefore imperative to represent these dynamics in Earth System Models (ESMs) by introducing sub-models that accurately represent microbial and abiotic processes. In the present study we explore, both analytically and numerically, four microbe-enabled model structures of varying levels of complexity. The most complex model combines microbial physiology, a non-linear mineral sorption isotherm, and enzyme dynamics. Based on detailed stability analysis of the nonlinear dynamics, we calculate the system modes as functions of model parameters. This dependence provides insight into the source of state oscillations. We find that feedback mechanisms that emerge from careful representation of enzyme and mineral interactions, with parameter values in a prescribed range, are critical for both maintaining system stability and capturing realistic responses to disturbances. Corroborating and expanding upon the results of recent studies, we explain the emergence of oscillatory responses and discuss the appropriate microbe-enabled model structure for inclusion in ESMs. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=polio&pg=2&id=ED519237','ERIC'); return false;" href="https://eric.ed.gov/?q=polio&pg=2&id=ED519237">Factors Influencing Oral Corrective Feedback Provision in the Spanish Foreign Language Classroom: Investigating Instructor Native/Nonnative Speaker Status, SLA Education, & Teaching Experience</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Gurzynski-Weiss, Laura 2010-01-01 The role of interactional feedback has been a critical area of second language acquisition (SLA) research for decades and while findings suggest interactional feedback can facilitate SLA, the extent of its influence can vary depending on a number of factors, including the native language of those involved in communication. Although studies have… </li> <li> <a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140005682','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140005682">CGILS: Results from the First Phase of an International Project to Understand the Physical Mechanisms of Low Cloud Feedbacks in Single Column Models</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Zhang, Minghua; Bretherton, Christopher S.; Blossey, Peter N.; Austin, Phillip H.; Bacmeister, Julio T.; Bony, Sandrine; Brient, Florent; Cheedela, Suvarchal K.; Cheng, Anning; DelGenio, Anthony; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20140005682'); toggleEditAbsImage('author_20140005682_show'); toggleEditAbsImage('author_20140005682_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20140005682_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20140005682_hide"> 2013-01-01 1] CGILS-the CFMIP-GASS Intercomparison of Large Eddy Models (LESs) and single column models (SCMs)-investigates the mechanisms of cloud feedback in SCMs and LESs under idealized climate change perturbation. This paper describes the CGILS results from 15 SCMs and 8 LES models. Three cloud regimes over the subtropical oceans are studied: shallow cumulus, cumulus under stratocumulus, and well-mixed coastal stratus/stratocumulus. In the stratocumulus and coastal stratus regimes, SCMs without activated shallow convection generally simulated negative cloud feedbacks, while models with active shallow convection generally simulated positive cloud feedbacks. In the shallow cumulus alone regime, this relationship is less clear, likely due to the changes in cloud depth, lateral mixing, and precipitation or a combination of them. The majority of LES models simulated negative cloud feedback in the well-mixed coastal stratus/stratocumulus regime, and positive feedback in the shallow cumulus and stratocumulus regime. A general framework is provided to interpret SCM results: in a warmer climate, the moistening rate of the cloudy layer associated with the surface-based turbulence parameterization is enhanced; together with weaker large-scale subsidence, it causes negative cloud feedback. In contrast, in the warmer climate, the drying rate associated with the shallow convection scheme is enhanced. This causes positive cloud feedback. These mechanisms are summarized as the "NESTS" negative cloud feedback and the "SCOPE" positive cloud feedback (Negative feedback from Surface Turbulence under weaker Subsidence-Shallow Convection PositivE feedback) with the net cloud feedback depending on how the two opposing effects counteract each other. The LES results are consistent with these interpretations </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28857586','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28857586">Relations between third grade teachers' depressive symptoms and their feedback to students, with implications for student mathematics achievement.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> McLean, Leigh; Connor, Carol McDonald 2018-06-01 Recent studies have observed connections among teachers' depressive symptoms and student outcomes; however, the specific mechanisms through which teachers' mental health characteristics operate in the classroom remain largely unknown. The present study used student-level observation methods to examine the relations between third-grade teachers' (N = 32) depressive symptoms and their academic feedback to students (N = 310) and sought to make inferences about how these factors might influence students' mathematics achievement. A novel observational tool, the Teacher Feedback Coding System-Academic (TFCS-A), was used that assesses feedback across 2 dimensions-teacher affect and instructional strategy, which have been shown to be important to student learning. Multilevel exploratory factor analysis of TFCS-A data suggested 2 primary factors: positive feedback and neutral/negative feedback. Hierarchical linear modeling revealed that positive feedback was related to higher math achievement among students who began the year with weaker math skills and that teachers who reported more depressive symptoms less frequently provided this positive feedback. Results offer new information about a type of instruction that may be affected by teachers' depressive symptoms and inform efforts aimed at improving teachers' instructional interactions with students. (PsycINFO Database Record (c) 2018 APA, all rights reserved). </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018OptLE.105..150Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018OptLE.105..150Z">Improvement on vibration measurement performance of laser self-mixing interference by using a pre-feedback mirror</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Zhu, Wei; Chen, Qianghua; Wang, Yanghong; Luo, Huifu; Wu, Huan; Ma, Binwu 2018-06-01 In the laser self-mixing interference vibration measurement system, the self mixing interference signal is usually weak so that it can be hardly distinguished from the environmental noise. In order to solve this problem, we present a self-mixing interference optical path with a pre-feedback mirror, a pre-feedback mirror is added between the object and the collimator lens, corresponding feedback light enters into the inner cavity of the laser and the interference by the pre-feedback mirror occurs. The pre-feedback system is established after that. The self-mixing interference theoretical model with a pre-feedback based on the F-P model is derived. The theoretical analysis shows that the amplitude of the intensity of the interference signal can be improved by 2-4 times. The influence factors of system are also discussed. The experiment results show that the amplitude of the signal is greatly improved, which agrees with the theoretical analysis. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMGC13A1052Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMGC13A1052Y">Mesoscale modeling of smoke radiative feedback over the Sahel region</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Yang, Z.; Wang, J.; Ichoku, C. M.; Ellison, L.; Zhang, F.; Yue, Y. 2013-12-01 This study employs satellite observations and a fully-coupled meteorology-chemistry-aerosol model, Weather Research and Forecasting model with Chemistry (WRF-Chem) to study the smoke radative feedback on surface energy budget, boundary layer processes, and atmospheric lapse rate in February 2008 over the Sahel region. The smoke emission inventories we use come from various sources, including but not limited to the Fire Locating and Modeling of Burning Emissions (FLAMBE) developed by NRL and the Fire Energetic and Emissions Research (FEER) developed by NASA GSFC. Model performance is evaluated using numerous satellite and ground-based datasets: MODIS true color images, ground-based Aerosol Optical Depth (AOD) measurements from AERONET, MODIS AOD retrievals, and Cloud-Aerosol Lidar data with Orthogonal Polarization (CALIOP) atmospheric backscattering and extinction products. Specification of smoke injection height of 650 m in WRF-Chem yields aerosol vertical profiles that are most consistent with CALIOP observations of aerosol layer height. Statistically, 5% of the CALIPSO valid measurements of aerosols in February 2008 show aerosol layers either above the clouds or between the clouds, reinforcing the importance of the aerosol vertical distribution for quantifying aerosol impact on climate in the Sahel region. The results further show that the smoke radiative feedbacks are sensitive to assumptions of black carbon and organic carbon ratio in the particle emission inventory. Also investigated is the smoke semi-direct effect as a function of cloud fraction. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19550188','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19550188">Who wants feedback? An investigation of the variables influencing residents' feedback-seeking behavior in relation to night shifts.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Teunissen, Pim W; Stapel, Diederik A; van der Vleuten, Cees; Scherpbier, Albert; Boor, Klarke; Scheele, Fedde 2009-07-01 The literature on feedback in clinical medical education has predominantly treated trainees as passive recipients. Past research has focused on how clinical supervisors can use feedback to improve a trainee's performance. On the basis of research in social and organizational psychology, the authors reconceptualized residents as active seekers of feedback. They investigated what individual and situational variables influence residents' feedback-seeking behavior on night shifts. Early in 2008, the authors sent obstetrics-gynecology residents in the Netherlands--both those in their first two years of graduate training and those gaining experience between undergraduate and graduate training--a questionnaire that assessed four predictor variables (learning and performance goal orientation, and instrumental and supportive leadership), two mediator variables (perceived feedback benefits and costs), and two outcome variables (frequency of feedback inquiry and monitoring). They used structural equation modeling software to test a hypothesized model of relationships between variables. The response rate was 76.5%. Results showed that residents who perceive more feedback benefits report a higher frequency of feedback inquiry and monitoring. More perceived feedback costs result mainly in more feedback monitoring. Residents with a higher learning goal orientation perceive more feedback benefits and fewer costs. Residents with a higher performance goal orientation perceive more feedback costs. Supportive physicians lead residents to perceive more feedback benefits and fewer costs. This study showed that some residents actively seek feedback. Residents' feedback-seeking behavior partially depends on attending physicians' supervisory style. Residents' goal orientations influence their perceptions of the benefits and costs of feedback-seeking. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=Dul&id=EJ349664','ERIC'); return false;" href="https://eric.ed.gov/?q=Dul&id=EJ349664">Instructional Feedback in Motor Skill Learning.</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Dul, J.; And Others 1987-01-01 Presents a model of the role of instructional feedback in learning a motor skill and identifies six levels of motor skill output, each of which has a characteristic type of feedback. The usefulness of several feedback techniques reported in the literature is discussed. (Author/LRW) </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMOS54A..02J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMOS54A..02J">Buffer capacity, ecosystem feedbacks, and seawater chemistry under global change</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Jury, C. P.; Thomas, F. I.; Atkinson, M. J.; Jokiel, P. L.; Onuma, M. A.; Kaku, N.; Toonen, R. J. 2013-12-01 Ocean acidification (OA) results in reduced seawater pH and aragonite saturation state (Ωarag), but also reduced seawater buffer capacity. As buffer capacity decreases, diel variation in seawater chemistry increases. However, a variety of ecosystem feedbacks can modulate changes in both average seawater chemistry and diel seawater chemistry variation. Here we model these effects for a coastal, reef flat ecosystem. We show that an increase in offshore pCO2 and temperature (to 900 μatm and +3°C) can increase diel pH variation by as much as a factor of 2.5 and can increase diel pCO2 variation by a factor of 4.6, depending on ecosystem feedbacks and seawater residence time. Importantly, these effects are different between day and night. With increasing seawater residence time and increasing feedback intensity, daytime seawater chemistry becomes more similar to present-day conditions while nighttime seawater chemistry becomes less similar to present-day conditions. Better constraining ecosystem feedbacks under global change will improve projections of coastal water chemistry, but this study shows the importance of considering changes in both average carbonate chemistry and diel chemistry variation for organisms and ecosystems. Further, we will discuss our recent work examining the effects of diel seawater chemistry variation on coral calcification rates. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21294008','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21294008">Active muscle response using feedback control of a finite element human arm model.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Östh, Jonas; Brolin, Karin; Happee, Riender 2012-01-01 Mathematical human body models (HBMs) are important research tools that are used to study the human response in car crash situations. Development of automotive safety systems requires the implementation of active muscle response in HBM, as novel safety systems also interact with vehicle occupants in the pre-crash phase. In this study, active muscle response was implemented using feedback control of a nonlinear muscle model in the right upper extremity of a finite element (FE) HBM. Hill-type line muscle elements were added, and the active and passive properties were assessed. Volunteer tests with low impact loading resulting in elbow flexion motions were performed. Simulations of posture maintenance in a gravity field and the volunteer tests were successfully conducted. It was concluded that feedback control of a nonlinear musculoskeletal model can be used to obtain posture maintenance and human-like reflexive responses in an FE HBM. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002PhRvE..65e6106T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002PhRvE..65e6106T">Evolution model with a cumulative feedback coupling</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Trimper, Steffen; Zabrocki, Knud; Schulz, Michael 2002-05-01 The paper is concerned with a toy model that generalizes the standard Lotka-Volterra equation for a certain population by introducing a competition between instantaneous and accumulative, history-dependent nonlinear feedback the origin of which could be a contribution from any kind of mismanagement in the past. The results depend on the sign of that additional cumulative loss or gain term of strength λ. In case of a positive coupling the system offers a maximum gain achieved after a finite time but the population will die out in the long time limit. In this case the instantaneous loss term of strength u is irrelevant and the model exhibits an exact solution. In the opposite case λ<0 the time evolution of the system is terminated in a crash after ts provided u=0. This singularity after a finite time can be avoided if u≠0. The approach may well be of relevance for the qualitative understanding of more realistic descriptions. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20080045502&hterms=Early+dwarf+stars&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DEarly%2Bdwarf%2Bstars','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20080045502&hterms=Early+dwarf+stars&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DEarly%2Bdwarf%2Bstars">Resolving the Formation of Protogalaxies. 3; Feedback from the First Stars</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Wise, John H.; Abel, Tom 2008-01-01 The first stars form in dark matter halos of masses 106 M as suggested by an increasing number of numerical simulations. Radiation feedback from these stars expels most of the gas from the shallow potential well of their surrounding dark matter halos.We use cosmological adaptive mesh refinement simulations that include self-consistent Population III star formation and feedback to examine the properties of assembling early dwarf galaxies. Accurate radiative transport is modeled with adaptive ray tracing. We include supernova explosions and follow the metal enrichment of the intergalactic medium. The calculations focus on the formation of several dwarf galaxies and their progenitors. In these halos, baryon fractions in 10(exp 8) Stelar Mass halos decrease by a factor of 2 with stellar feedback and by a factor of 3 with supernova explosions.We find that radiation feedback and supernova explosions increase gaseous spin parameters up to a factor of 4 and vary with time. Stellar feedback, supernova explosions, and H2 cooling create a complex, multiphase interstellar medium whose densities and temperatures can span up to 6 orders of magnitude at a given radius. The pair-instability supernovae of Population III stars alone enrich the halos with virial temperatures of 10(exp 4) K to approximately 10(exp -3) of solar metallicity.We find that 40% of the heavy elements resides in the intergalactic medium (IGM) at the end of our calculations. The highest metallicity gas exists in supernova remnants and very dilute regions of the IGM. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013cctp.book..163C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013cctp.book..163C">The Greenhouse Effect and Climate Feedbacks</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Covey, C.; Haberle, R. M.; McKay, C. P.; Titov, D. V. This chapter reviews the theory of the greenhouse effect and climate feedback. It also compares the theory with observations, using examples taken from all four known terrestrial worlds with substantial atmospheres: Venus, Earth, Mars, and Titan. The greenhouse effect traps infrared radiation in the atmosphere, thereby increasing surface temperature. It is one of many factors that affect a world's climate. (Others include solar luminosity and the atmospheric scattering and absorption of solar radiation.) A change in these factors — defined as climate forcing — may change the climate in a way that brings other processes — defined as feedbacks — into play. For example, when Earth's atmospheric carbon dioxide increases, warming the surface, the water vapor content of the atmosphere increases. This is a positive feedback on global warming because water vapor is itself a potent greenhouse gas. Many positive and negative feedback processes are significant in determining Earth's climate, and probably the climates of our terrestrial neighbors. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15169072','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15169072">Neural cryptography with feedback.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Ruttor, Andreas; Kinzel, Wolfgang; Shacham, Lanir; Kanter, Ido 2004-04-01 Neural cryptography is based on a competition between attractive and repulsive stochastic forces. A feedback mechanism is added to neural cryptography which increases the repulsive forces. Using numerical simulations and an analytic approach, the probability of a successful attack is calculated for different model parameters. Scaling laws are derived which show that feedback improves the security of the system. In addition, a network with feedback generates a pseudorandom bit sequence which can be used to encrypt and decrypt a secret message. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2590583','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2590583">Computational Modeling of Morphogenesis Regulated by Mechanical Feedback</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Ramasubramanian, Ashok; Taber, Larry A. 2008-01-01 Mechanical forces cause changes in form during embryogenesis and likely play a role in regulating these changes. This paper explores the idea that changes in homeostatic tissue stress (target stress), possibly modulated by genes, drive some morphogenetic processes. Computational models are presented to illustrate how regional variations in target stress can cause a range of complex behaviors involving the bending of epithelia. These models include growth and cytoskeletal contraction regulated by stress-based mechanical feedback. All simulations were carried out using the commercial finite element code ABAQUS, with growth and contraction included by modifying the zero-stress state in the material constitutive relations. Results presented for bending of bilayered beams and invagination of cylindrical and spherical shells provide insight into some of the mechanical aspects that must be considered in studying morphogenetic mechanisms. PMID:17318485 </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active">9</li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_10" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active">10</li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="181"> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AtmEn.115..442M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AtmEn.115..442M">Feedbacks between air pollution and weather, Part 1: Effects on weather</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Makar, P. A.; Gong, W.; Milbrandt, J.; Hogrefe, C.; Zhang, Y.; Curci, G.; Žabkar, R.; Im, U.; Balzarini, A.; Baró, R.; Bianconi, R.; Cheung, P.; Forkel, R.; Gravel, S.; Hirtl, M.; Honzak, L.; Hou, A.; Jiménez-Guerrero, P.; Langer, M.; Moran, M. D.; Pabla, B.; Pérez, J. L.; Pirovano, G.; San José, R.; Tuccella, P.; Werhahn, J.; Zhang, J.; Galmarini, S. 2015-08-01 The meteorological predictions of fully coupled air-quality models running in ;feedback; versus ;no-feedback; simulations were compared against each other and observations as part of Phase 2 of the Air Quality Model Evaluation International Initiative. In the ;no-feedback; mode, the aerosol direct and indirect effects were disabled, with the models reverting to either climatologies of aerosol properties, or a no-aerosol weather simulation. In the ;feedback; mode, the model-generated aerosols were allowed to modify the radiative transfer and/or cloud formation parameterizations of the respective models. Annual simulations with and without feedbacks were conducted on domains over North America for the years 2006 and 2010, and over Europe for the year 2010. The incorporation of feedbacks was found to result in systematic changes to forecast predictions of meteorological variables, both in time and space, with the largest impacts occurring in the summer and near large sources of pollution. Models incorporating only the aerosol direct effect predicted feedback-induced reductions in temperature, surface downward and upward shortwave radiation, precipitation and PBL height, and increased upward shortwave radiation, in both Europe and North America. The feedback response of models incorporating both the aerosol direct and indirect effects varied across models, suggesting the details of implementation of the indirect effect have a large impact on model results, and hence should be a focus for future research. The feedback response of models incorporating both direct and indirect effects was also consistently larger in magnitude to that of models incorporating the direct effect alone, implying that the indirect effect may be the dominant process. Comparisons across modelling platforms suggested that direct and indirect effect feedbacks may often act in competition: the sign of residual changes associated with feedbacks often changed between those models incorporating the </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JNEng..10b6016G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JNEng..10b6016G">Model-based rational feedback controller design for closed-loop deep brain stimulation of Parkinson's disease</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Gorzelic, P.; Schiff, S. J.; Sinha, A. 2013-04-01 Objective. To explore the use of classical feedback control methods to achieve an improved deep brain stimulation (DBS) algorithm for application to Parkinson's disease (PD). Approach. A computational model of PD dynamics was employed to develop model-based rational feedback controller design. The restoration of thalamocortical relay capabilities to patients suffering from PD is formulated as a feedback control problem with the DBS waveform serving as the control input. Two high-level control strategies are tested: one that is driven by an online estimate of thalamic reliability, and another that acts to eliminate substantial decreases in the inhibition from the globus pallidus interna (GPi) to the thalamus. Control laws inspired by traditional proportional-integral-derivative (PID) methodology are prescribed for each strategy and simulated on this computational model of the basal ganglia network. Main Results. For control based upon thalamic reliability, a strategy of frequency proportional control with proportional bias delivered the optimal control achieved for a given energy expenditure. In comparison, control based upon synaptic inhibitory output from the GPi performed very well in comparison with those of reliability-based control, with considerable further reduction in energy expenditure relative to that of open-loop DBS. The best controller performance was amplitude proportional with derivative control and integral bias, which is full PID control. We demonstrated how optimizing the three components of PID control is feasible in this setting, although the complexity of these optimization functions argues for adaptive methods in implementation. Significance. Our findings point to the potential value of model-based rational design of feedback controllers for Parkinson's disease. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23449002','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23449002">Model-based rational feedback controller design for closed-loop deep brain stimulation of Parkinson's disease.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Gorzelic, P; Schiff, S J; Sinha, A 2013-04-01 To explore the use of classical feedback control methods to achieve an improved deep brain stimulation (DBS) algorithm for application to Parkinson's disease (PD). A computational model of PD dynamics was employed to develop model-based rational feedback controller design. The restoration of thalamocortical relay capabilities to patients suffering from PD is formulated as a feedback control problem with the DBS waveform serving as the control input. Two high-level control strategies are tested: one that is driven by an online estimate of thalamic reliability, and another that acts to eliminate substantial decreases in the inhibition from the globus pallidus interna (GPi) to the thalamus. Control laws inspired by traditional proportional-integral-derivative (PID) methodology are prescribed for each strategy and simulated on this computational model of the basal ganglia network. For control based upon thalamic reliability, a strategy of frequency proportional control with proportional bias delivered the optimal control achieved for a given energy expenditure. In comparison, control based upon synaptic inhibitory output from the GPi performed very well in comparison with those of reliability-based control, with considerable further reduction in energy expenditure relative to that of open-loop DBS. The best controller performance was amplitude proportional with derivative control and integral bias, which is full PID control. We demonstrated how optimizing the three components of PID control is feasible in this setting, although the complexity of these optimization functions argues for adaptive methods in implementation. Our findings point to the potential value of model-based rational design of feedback controllers for Parkinson's disease. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=gymnastics&pg=2&id=EJ868607','ERIC'); return false;" href="https://eric.ed.gov/?q=gymnastics&pg=2&id=EJ868607">Video Modeling by Experts with Video Feedback to Enhance Gymnastics Skills</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Boyer, Eva; Miltenberger, Raymond G.; Batsche, Catherine; Fogel, Victoria 2009-01-01 The effects of combining video modeling by experts with video feedback were analyzed with 4 female competitive gymnasts (7 to 10 years old) in a multiple baseline design across behaviors. During the intervention, after the gymnast performed a specific gymnastics skill, she viewed a video segment showing an expert gymnast performing the same skill… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5627951','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5627951">A new discrete dynamic model of ABA-induced stomatal closure predicts key feedback loops</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Acharya, Biswa R.; Jeon, Byeong Wook; Zañudo, Jorge G. T.; Zhu, Mengmeng; Osman, Karim; Assmann, Sarah M. 2017-01-01 Stomata, microscopic pores in leaf surfaces through which water loss and carbon dioxide uptake occur, are closed in response to drought by the phytohormone abscisic acid (ABA). This process is vital for drought tolerance and has been the topic of extensive experimental investigation in the last decades. Although a core signaling chain has been elucidated consisting of ABA binding to receptors, which alleviates negative regulation by protein phosphatases 2C (PP2Cs) of the protein kinase OPEN STOMATA 1 (OST1) and ultimately results in activation of anion channels, osmotic water loss, and stomatal closure, over 70 additional components have been identified, yet their relationships with each other and the core components are poorly elucidated. We integrated and processed hundreds of disparate observations regarding ABA signal transduction responses underlying stomatal closure into a network of 84 nodes and 156 edges and, as a result, established those relationships, including identification of a 36-node, strongly connected (feedback-rich) component as well as its in- and out-components. The network’s domination by a feedback-rich component may reflect a general feature of rapid signaling events. We developed a discrete dynamic model of this network and elucidated the effects of ABA plus knockout or constitutive activity of 79 nodes on both the outcome of the system (closure) and the status of all internal nodes. The model, with more than 1024 system states, is far from fully determined by the available data, yet model results agree with existing experiments in 82 cases and disagree in only 17 cases, a validation rate of 75%. Our results reveal nodes that could be engineered to impact stomatal closure in a controlled fashion and also provide over 140 novel predictions for which experimental data are currently lacking. Noting the paucity of wet-bench data regarding combinatorial effects of ABA and internal node activation, we experimentally confirmed several </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/51748-high-performance-ripple-feedback-buck-unity-power-factor-rectifier','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/51748-high-performance-ripple-feedback-buck-unity-power-factor-rectifier">High performance ripple feedback for the buck unity-power-factor rectifier</a> <a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a> Lo, Y.W.; King, R.J. 1995-03-01 The buck unity-power-factor rectifier has harmonic-free input current with complete load regulation down to zero output voltage. A new ``nonlinear ripple feedback`` is proposed which exactly cancels the spoiling effect of dc-side current ripple on the low-distortion ac line current waveforms, even for large amounts of ripple. This cancellation is independent of operating point and readily implemented with analog hardware, thereby permitting economies in the design of the dc filter while maintaining harmonic-free operation. Both large-signal and incremental analyses of the rectifier are given. Confirming experimental results from a 1-kW 48-V isolated battery charger operating with current-ripple levels ranging frommore » 50% to discontinuous-conduction-mode operation are given.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('https://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=250572&Lab=NERL&keyword=Influence+AND+clouds+AND+climate&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50','EPA-EIMS'); return false;" href="https://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=250572&Lab=NERL&keyword=Influence+AND+clouds+AND+climate&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50">Introducing Subrid-scale Cloud Feedbacks to Radiation for Regional Meteorological and Cllimate Modeling</a> <a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a> Convection systems and associated cloudiness directly influence regional and local radiation budgets, and dynamics and thermodynamics through feedbacks. However, most subgrid-scale convective parameterizations in regional weather and climate models do not consider cumulus cloud ... </li> <li> <a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840020468','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840020468">Design of multivariable feedback control systems via spectral assignment using reduced-order models and reduced-order observers</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Mielke, R. R.; Tung, L. J.; Carraway, P. I., III 1984-01-01 The feasibility of using reduced order models and reduced order observers with eigenvalue/eigenvector assignment procedures is investigated. A review of spectral assignment synthesis procedures is presented. Then, a reduced order model which retains essential system characteristics is formulated. A constant state feedback matrix which assigns desired closed loop eigenvalues and approximates specified closed loop eigenvectors is calculated for the reduced order model. It is shown that the eigenvalue and eigenvector assignments made in the reduced order system are retained when the feedback matrix is implemented about the full order system. In addition, those modes and associated eigenvectors which are not included in the reduced order model remain unchanged in the closed loop full order system. The full state feedback design is then implemented by using a reduced order observer. It is shown that the eigenvalue and eigenvector assignments of the closed loop full order system rmain unchanged when a reduced order observer is used. The design procedure is illustrated by an actual design problem. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19850015489','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19850015489">Design of multivariable feedback control systems via spectral assignment using reduced-order models and reduced-order observers</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Mielke, R. R.; Tung, L. J.; Carraway, P. I., III 1985-01-01 The feasibility of using reduced order models and reduced order observers with eigenvalue/eigenvector assignment procedures is investigated. A review of spectral assignment synthesis procedures is presented. Then, a reduced order model which retains essential system characteristics is formulated. A constant state feedback matrix which assigns desired closed loop eigenvalues and approximates specified closed loop eigenvectors is calculated for the reduced order model. It is shown that the eigenvalue and eigenvector assignments made in the reduced order system are retained when the feedback matrix is implemented about the full order system. In addition, those modes and associated eigenvectors which are not included in the reduced order model remain unchanged in the closed loop full order system. The fulll state feedback design is then implemented by using a reduced order observer. It is shown that the eigenvalue and eigenvector assignments of the closed loop full order system remain unchanged when a reduced order observer is used. The design procedure is illustrated by an actual design problem. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013PhDT........71F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PhDT........71F">The local, remote, and global consequences of climate feedbacks</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Feldl, Nicole Climate feedbacks offer a powerful framework for revealing the energetic pathways by which the system adjusts to an imposed forcing, such as an increase in atmospheric CO2. We investigate how local atmospheric feedbacks, such as those associated with Arctic sea ice and the Walker circulation, affect both global climate sensitivity and spatial patterns of warming. Emphasis is placed on a general circulation model with idealized boundary conditions, for the clarity it provides. For this aquaplanet simulation, we account for rapid tropospheric adjustments to CO2 and explicitly diagnose feedbacks (using radiative kernels) and forcing for this precise model set-up. In particular, a detailed closure of the energy budget within a clean experimental set-up allows us to consider nonlinear interactions between feedbacks. The inclusion of a tropical Walker circulation is found to prime the Hadley Circulation for a larger deceleration under CO2 doubling, by altering subtropical stratus decks and the meridional feedback gradient. We perform targeted experiments to isolate the atmospheric processes responsible for the variability in climate sensitivity, with implications for high-sensitivity paleoclimates. The local climate response is characterized in terms of the meridional structure of feedbacks, atmospheric heat transport, nonlinearities, and forcing. Our results display a combination of positive subtropical feedbacks and polar amplified warming. These two factors imply a critical role for transport and nonlinear effects, with the latter acting to substantially reduce global climate sensitivity. At the hemispheric scale, a rich picture emerges: anomalous divergence of heat flux away from positive feedbacks in the subtropics; clear-sky nonlinearities that reinforce the pattern of tropical cooling and high-latitude warming tendencies; and strong ice-line feedbacks that drive further amplification of polar warming. These results have implications for regional climate </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=information+AND+technology+AND+artificial+AND+intelligence&pg=5&id=EJ1148530','ERIC'); return false;" href="https://eric.ed.gov/?q=information+AND+technology+AND+artificial+AND+intelligence&pg=5&id=EJ1148530">New Directions in Formative Feedback in Interactive Learning Environments</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Goldin, Ilya; Narciss, Susanne; Foltz, Peter; Bauer, Malcolm 2017-01-01 Formative feedback is well known as a key factor in influencing learning. Modern interactive learning environments provide a broad range of ways to provide feedback to students as well as new tools to understand feedback and its relation to various learning outcomes. This issue focuses on the role of formative feedback through a lens of how… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19900043766&hterms=climate+change+deserts&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dclimate%2Bchange%2Bdeserts','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19900043766&hterms=climate+change+deserts&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dclimate%2Bchange%2Bdeserts">Investigation of biogeophysical feedback on the African climate using a two-dimensional model</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Xue, Yongkang; Liou, Kuo-Nan; Kasahara, Akira 1990-01-01 A numerical scheme is specifically designed to develop a time-dependent climate model to ensure the conservation of mass, momentum, energy, and water vapor, in order to study the biogeophysical feedback for the climate of Africa. A vegetation layer is incorporated in the present two-dimensional climate model. Using the coupled climate-vegetation model, two tests were performed involving the removal and expansion of the Sahara Desert. Results show that variations in the surface conditions produce a significant feedback to the climate system. It is noted that the simulation responses to the temperature and zonal wind in the case of an expanded desert agree with the climatological data for African dry years. Perturbed simulations have also been performed by changing the albedo only, without allowing the variation in the vegetation layer. It is shown that the variation in latent heat release is significant and is related to changes in the vegetation cover. As a result, precipitation and cloud cover are reduced. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=Descriptive+AND+Evaluative&pg=5&id=EJ867025','ERIC'); return false;" href="https://eric.ed.gov/?q=Descriptive+AND+Evaluative&pg=5&id=EJ867025">Effects of Differential Feedback on Students' Examination Performance</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Lipnevich, Anastasiya A.; Smith, Jeffrey K. 2009-01-01 The effects of feedback on performance and factors associated with it were examined in a large introductory psychology course. The experiment involved college students (N = 464) working on an essay examination under 3 conditions: no feedback, detailed feedback that was perceived by participants to be provided by the course instructor, and detailed… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=material+AND+studio&pg=6&id=EJ959267','ERIC'); return false;" href="https://eric.ed.gov/?q=material+AND+studio&pg=6&id=EJ959267">Making Movies: The Next Big Thing in Feedback?</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Hope, Sheila A. 2011-01-01 Good quality, timely feedback is a key factor to help students achieve their full potential. Increased class sizes have put significant strain on the ability to return work promptly without compromising feedback quality. In the current study, two screencasting technologies were used to produce audiovisual feedback. For essays, Jing was used,… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21833250','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21833250">Frequent external-focus feedback enhances motor learning.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Wulf, Gabriele; Chiviacowsky, Suzete; Schiller, Eduardo; Avila, Luciana Toaldo Gentilini 2010-01-01 The present study examined the hypothesis that feedback inducing an external focus of attention enhances motor learning if it is provided frequently (i.e., 100%) rather than less frequently. Children (10- to 12-year-olds) practiced a soccer throw-in task and were provided feedback about movement form. The feedback statements, provided either after every (100%) or every third (33%) practice trial, were similar in content but induced either an internal focus (body-movement related) or external focus (movement-effect related). The results demonstrated that learning of the movement form was enhanced by external-focus feedback after every trial (100%) relative to external-focus feedback after every third trial (33%) or internal-focus feedback (100%, 33%), as demonstrated by immediate and delayed transfer tests without feedback. There was no difference between the two internal-focus feedback groups. These findings indicate that the attentional focus induced by feedback is an important factor in determining the effectiveness of different feedback frequencies. We argue that the informational properties of feedback cannot sufficiently account for these and related findings, and suggest that the attentional role of feedback be given greater consideration in future studies. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29765038','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29765038">Quantifying climate feedbacks in polar regions.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Goosse, Hugues; Kay, Jennifer E; Armour, Kyle C; Bodas-Salcedo, Alejandro; Chepfer, Helene; Docquier, David; Jonko, Alexandra; Kushner, Paul J; Lecomte, Olivier; Massonnet, François; Park, Hyo-Seok; Pithan, Felix; Svensson, Gunilla; Vancoppenolle, Martin 2018-05-15 The concept of feedback is key in assessing whether a perturbation to a system is amplified or damped by mechanisms internal to the system. In polar regions, climate dynamics are controlled by both radiative and non-radiative interactions between the atmosphere, ocean, sea ice, ice sheets and land surfaces. Precisely quantifying polar feedbacks is required for a process-oriented evaluation of climate models, a clear understanding of the processes responsible for polar climate changes, and a reduction in uncertainty associated with model projections. This quantification can be performed using a simple and consistent approach that is valid for a wide range of feedbacks, offering the opportunity for more systematic feedback analyses and a better understanding of polar climate changes. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22208135','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22208135">Examination of a perceived cost model of employees' negative feedback-seeking behavior.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Lu, Kuo-Ming; Pan, Su-Ying; Cheng, Jen-Wei 2011-01-01 The present study extends the feedback-seeking behavior literature by investigating how supervisor-related antecedents (i.e., supervisors' expert power, reflected appraisals of supervisors, and supervisors' emotional intelligence) influence subordinates' negative feedback-seeking behavior (NFSB) through different cost/value perceptions (i.e., expectancy value, self-presentation cost, and ego cost). Using data collected from 216 supervisor-subordinate dyads from various industries in Taiwan, we employ structural equation modeling analysis to test our hypotheses. The results show that expectancy value mediates the relationship between supervisor expert power and subordinates' NFSB. Moreover, self-presentation cost mediates the relationship between reflected appraisals of supervisors' and subordinates' NFSB. Theoretical and practical implications of this study are also discussed. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28919872','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28919872">Follower-Centered Perspective on Feedback: Effects of Feedback Seeking on Identification and Feedback Environment.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Gong, Zhenxing; Li, Miaomiao; Qi, Yaoyuan; Zhang, Na 2017-01-01 In the formation mechanism of the feedback environment, the existing research pays attention to external feedback sources and regards individuals as objects passively accepting feedback. Thus, the external source fails to realize the individuals' need for feedback, and the feedback environment cannot provide them with useful information, leading to a feedback vacuum. The aim of this study is to examine the effect of feedback-seeking by different strategies on the supervisor-feedback environment through supervisor identification. The article consists of an empirical study with a sample of 264 employees in China; here, participants complete a series of questionnaires in three waves. After controlling for the effects of demography, the results indicate that supervisor identification partially mediates the relationship between feedback-seeking (including feedback monitoring and feedback inquiry) and the supervisor-feedback environment. Implications are also discussed. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5585180','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5585180">Follower-Centered Perspective on Feedback: Effects of Feedback Seeking on Identification and Feedback Environment</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Gong, Zhenxing; Li, Miaomiao; Qi, Yaoyuan; Zhang, Na 2017-01-01 In the formation mechanism of the feedback environment, the existing research pays attention to external feedback sources and regards individuals as objects passively accepting feedback. Thus, the external source fails to realize the individuals’ need for feedback, and the feedback environment cannot provide them with useful information, leading to a feedback vacuum. The aim of this study is to examine the effect of feedback-seeking by different strategies on the supervisor-feedback environment through supervisor identification. The article consists of an empirical study with a sample of 264 employees in China; here, participants complete a series of questionnaires in three waves. After controlling for the effects of demography, the results indicate that supervisor identification partially mediates the relationship between feedback-seeking (including feedback monitoring and feedback inquiry) and the supervisor-feedback environment. Implications are also discussed. PMID:28919872 </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018OptCo.410..690C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018OptCo.410..690C">Modeling and experimental verification of laser self-mixing interference phenomenon with the structure of two-external-cavity feedback</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Chen, Peng; Liu, Yuwei; Gao, Bingkun; Jiang, Chunlei 2018-03-01 A semiconductor laser employed with two-external-cavity feedback structure for laser self-mixing interference (SMI) phenomenon is investigated and analyzed. The SMI model with two directions based on F-P cavity is deduced, and numerical simulation and experimental verification were conducted. Experimental results show that the SMI with the structure of two-external-cavity feedback under weak light feedback is similar to the sum of two SMIs. </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active">10</li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active">11</li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.A41K3205J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.A41K3205J">The highs and lows of cloud radiative feedback: Comparing observational data and CMIP5 models</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Jenney, A.; Randall, D. A. 2014-12-01 Clouds play a complex role in the climate system, and remain one of the more difficult aspects of the future climate to predict. Over subtropical eastern ocean basins, particularly next to California, Peru, and Southwest Africa, low marine stratocumulus clouds (MSC) help to reduce the amount of solar radiation that reaches the surface by reflecting incident sunlight. The climate feedback associated with these clouds is thought to be positive. This project looks at CMIP5 models and compares them to observational data from CERES and ERA-Interim to try and find observational evidence and model agreement for low, marine stratocumulus cloud feedback. Although current evidence suggests that the low cloud feedback is positive (IPCC, 2014), an analysis of the simulated relationship between July lower tropospheric stability (LTS) and shortwave cloud forcing in MSC regions suggests that this feedback is not due to changes in LTS. IPCC, 2013: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 1535 pp. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28008136','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28008136">How does feedback in mini-CEX affect students' learning response?</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Sudarso, Sulistiawati; Rahayu, Gandes Retno; Suhoyo, Yoyo 2016-12-19 This study was aimed to explore students' learning response toward feedback during mini-CEX encounter. This study used a phenomenological approach to identify the students' experiences toward feedback during mini-CEX encounter. Data was collected using Focus Group Discussion (FGD) for all students who were in their final week of clerkship in the internal medicine rotation. There were 4 FGD groups (6 students for each group). All FGD were audio-taped and transcribed verbatim. The FGD transcripts were analyzed thematically and managed using Atlas-ti (version 7.0). Feedback content and the way of providing feedback on mini-CEX stimulated students' internal process, including self-reflection, emotional response, and motivation. These internal processes encouraged the students to take action or do a follow-up on the feedback to improve their learning process. In addition, there was also an external factor, namely consequences, which also influenced the students' reaction to the follow-up on feedback. In the end, this action caused several learning effects that resulted in the students' increased self-efficacy, attitude, knowledge and clinical skill. Feedback content and the way of providing feedback on mini-CEX stimulates the students' internal processes to do a follow-up on feedback. However, another external factor also affects the students' decision on the follow-up actions. The follow-ups result in various learning effects on the students. Feedback given along with summative assessment enhances learning effects on students, as well. It is suggested that supervisors of clinical education are prepared to comprehend every factor influencing feedback on mini CEX to improve the students' learning response. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PhLA..382..482Q','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PhLA..382..482Q">A new lattice hydrodynamic model based on control method considering the flux change rate and delay feedback signal</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Qin, Shunda; Ge, Hongxia; Cheng, Rongjun 2018-02-01 In this paper, a new lattice hydrodynamic model is proposed by taking delay feedback and flux change rate effect into account in a single lane. The linear stability condition of the new model is derived by control theory. By using the nonlinear analysis method, the mKDV equation near the critical point is deduced to describe the traffic congestion. Numerical simulations are carried out to demonstrate the advantage of the new model in suppressing traffic jam with the consideration of flux change rate effect in delay feedback model. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28753639','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28753639">Self-regulation strategy, feedback timing and hemodynamic properties modulate learning in a simulated fMRI neurofeedback environment.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Oblak, Ethan F; Lewis-Peacock, Jarrod A; Sulzer, James S 2017-07-01 Direct manipulation of brain activity can be used to investigate causal brain-behavior relationships. Current noninvasive neural stimulation techniques are too coarse to manipulate behaviors that correlate with fine-grained spatial patterns recorded by fMRI. However, these activity patterns can be manipulated by having people learn to self-regulate their own recorded neural activity. This technique, known as fMRI neurofeedback, faces challenges as many participants are unable to self-regulate. The causes of this non-responder effect are not well understood due to the cost and complexity of such investigation in the MRI scanner. Here, we investigated the temporal dynamics of the hemodynamic response measured by fMRI as a potential cause of the non-responder effect. Learning to self-regulate the hemodynamic response involves a difficult temporal credit-assignment problem because this signal is both delayed and blurred over time. Two factors critical to this problem are the prescribed self-regulation strategy (cognitive or automatic) and feedback timing (continuous or intermittent). Here, we sought to evaluate how these factors interact with the temporal dynamics of fMRI without using the MRI scanner. We first examined the role of cognitive strategies by having participants learn to regulate a simulated neurofeedback signal using a unidimensional strategy: pressing one of two buttons to rotate a visual grating that stimulates a model of visual cortex. Under these conditions, continuous feedback led to faster regulation compared to intermittent feedback. Yet, since many neurofeedback studies prescribe implicit self-regulation strategies, we created a computational model of automatic reward-based learning to examine whether this result held true for automatic processing. When feedback was delayed and blurred based on the hemodynamics of fMRI, this model learned more reliably from intermittent feedback compared to continuous feedback. These results suggest that different </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5550007','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5550007">Self-regulation strategy, feedback timing and hemodynamic properties modulate learning in a simulated fMRI neurofeedback environment</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Sulzer, James S. 2017-01-01 Direct manipulation of brain activity can be used to investigate causal brain-behavior relationships. Current noninvasive neural stimulation techniques are too coarse to manipulate behaviors that correlate with fine-grained spatial patterns recorded by fMRI. However, these activity patterns can be manipulated by having people learn to self-regulate their own recorded neural activity. This technique, known as fMRI neurofeedback, faces challenges as many participants are unable to self-regulate. The causes of this non-responder effect are not well understood due to the cost and complexity of such investigation in the MRI scanner. Here, we investigated the temporal dynamics of the hemodynamic response measured by fMRI as a potential cause of the non-responder effect. Learning to self-regulate the hemodynamic response involves a difficult temporal credit-assignment problem because this signal is both delayed and blurred over time. Two factors critical to this problem are the prescribed self-regulation strategy (cognitive or automatic) and feedback timing (continuous or intermittent). Here, we sought to evaluate how these factors interact with the temporal dynamics of fMRI without using the MRI scanner. We first examined the role of cognitive strategies by having participants learn to regulate a simulated neurofeedback signal using a unidimensional strategy: pressing one of two buttons to rotate a visual grating that stimulates a model of visual cortex. Under these conditions, continuous feedback led to faster regulation compared to intermittent feedback. Yet, since many neurofeedback studies prescribe implicit self-regulation strategies, we created a computational model of automatic reward-based learning to examine whether this result held true for automatic processing. When feedback was delayed and blurred based on the hemodynamics of fMRI, this model learned more reliably from intermittent feedback compared to continuous feedback. These results suggest that different </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29771919','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29771919">Firing-rate based network modeling of the dLGN circuit: Effects of cortical feedback on spatiotemporal response properties of relay cells.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Mobarhan, Milad Hobbi; Halnes, Geir; Martínez-Cañada, Pablo; Hafting, Torkel; Fyhn, Marianne; Einevoll, Gaute T 2018-05-01 Visually evoked signals in the retina pass through the dorsal geniculate nucleus (dLGN) on the way to the visual cortex. This is however not a simple feedforward flow of information: there is a significant feedback from cortical cells back to both relay cells and interneurons in the dLGN. Despite four decades of experimental and theoretical studies, the functional role of this feedback is still debated. Here we use a firing-rate model, the extended difference-of-Gaussians (eDOG) model, to explore cortical feedback effects on visual responses of dLGN relay cells. For this model the responses are found by direct evaluation of two- or three-dimensional integrals allowing for fast and comprehensive studies of putative effects of different candidate organizations of the cortical feedback. Our analysis identifies a special mixed configuration of excitatory and inhibitory cortical feedback which seems to best account for available experimental data. This configuration consists of (i) a slow (long-delay) and spatially widespread inhibitory feedback, combined with (ii) a fast (short-delayed) and spatially narrow excitatory feedback, where (iii) the excitatory/inhibitory ON-ON connections are accompanied respectively by inhibitory/excitatory OFF-ON connections, i.e. following a phase-reversed arrangement. The recent development of optogenetic and pharmacogenetic methods has provided new tools for more precise manipulation and investigation of the thalamocortical circuit, in particular for mice. Such data will expectedly allow the eDOG model to be better constrained by data from specific animal model systems than has been possible until now for cat. We have therefore made the Python tool pyLGN which allows for easy adaptation of the eDOG model to new situations. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1438357','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/1438357">Quantifying climate feedbacks in polar regions</a> <a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a> Goosse, Hugues; Kay, Jennifer E.; Armour, Kyle C. The concept of feedback is key in assessing whether a perturbation to a system is amplified or damped by mechanisms internal to the system. In polar regions, climate dynamics are controlled by both radiative and non-radiative interactions between the atmosphere, ocean, sea ice, ice sheets and land surfaces. Precisely quantifying polar feedbacks is required for a process-oriented evaluation of climate models, a clear understanding of the processes responsible for polar climate changes, and a reduction in uncertainty associated with model projections. This quantification can be performed using a simple and consistent approach that is valid for a wide range ofmore » feedbacks, thus offering the opportunity for more systematic feedback analyses and a better understanding of polar climate changes.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1438357-quantifying-climate-feedbacks-polar-regions','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1438357-quantifying-climate-feedbacks-polar-regions">Quantifying climate feedbacks in polar regions</a> <a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a> Goosse, Hugues; Kay, Jennifer E.; Armour, Kyle C.; ... 2018-05-15 The concept of feedback is key in assessing whether a perturbation to a system is amplified or damped by mechanisms internal to the system. In polar regions, climate dynamics are controlled by both radiative and non-radiative interactions between the atmosphere, ocean, sea ice, ice sheets and land surfaces. Precisely quantifying polar feedbacks is required for a process-oriented evaluation of climate models, a clear understanding of the processes responsible for polar climate changes, and a reduction in uncertainty associated with model projections. This quantification can be performed using a simple and consistent approach that is valid for a wide range ofmore » feedbacks, thus offering the opportunity for more systematic feedback analyses and a better understanding of polar climate changes.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.B23J..07B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.B23J..07B">Chasing Perfection: Should We Reduce Model Uncertainty in Carbon Cycle-Climate Feedbacks</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Bonan, G. B.; Lombardozzi, D.; Wieder, W. R.; Lindsay, K. T.; Thomas, R. Q. 2015-12-01 Earth system model simulations of the terrestrial carbon (C) cycle show large multi-model spread in the carbon-concentration and carbon-climate feedback parameters. Large differences among models are also seen in their simulation of global vegetation and soil C stocks and other aspects of the C cycle, prompting concern about model uncertainty and our ability to faithfully represent fundamental aspects of the terrestrial C cycle in Earth system models. Benchmarking analyses that compare model simulations with common datasets have been proposed as a means to assess model fidelity with observations, and various model-data fusion techniques have been used to reduce model biases. While such efforts will reduce multi-model spread, they may not help reduce uncertainty (and increase confidence) in projections of the C cycle over the twenty-first century. Many ecological and biogeochemical processes represented in Earth system models are poorly understood at both the site scale and across large regions, where biotic and edaphic heterogeneity are important. Our experience with the Community Land Model (CLM) suggests that large uncertainty in the terrestrial C cycle and its feedback with climate change is an inherent property of biological systems. The challenge of representing life in Earth system models, with the rich diversity of lifeforms and complexity of biological systems, may necessitate a multitude of modeling approaches to capture the range of possible outcomes. Such models should encompass a range of plausible model structures. We distinguish between model parameter uncertainty and model structural uncertainty. Focusing on improved parameter estimates may, in fact, limit progress in assessing model structural uncertainty associated with realistically representing biological processes. Moreover, higher confidence may be achieved through better process representation, but this does not necessarily reduce uncertainty. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007PMB....52.5831Q','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007PMB....52.5831Q">Inferential modeling and predictive feedback control in real-time motion compensation using the treatment couch during radiotherapy</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Qiu, Peng; D'Souza, Warren D.; McAvoy, Thomas J.; Liu, K. J. Ray 2007-09-01 Tumor motion induced by respiration presents a challenge to the reliable delivery of conformal radiation treatments. Real-time motion compensation represents the technologically most challenging clinical solution but has the potential to overcome the limitations of existing methods. The performance of a real-time couch-based motion compensation system is mainly dependent on two aspects: the ability to infer the internal anatomical position and the performance of the feedback control system. In this paper, we propose two novel methods for the two aspects respectively, and then combine the proposed methods into one system. To accurately estimate the internal tumor position, we present partial-least squares (PLS) regression to predict the position of the diaphragm using skin-based motion surrogates. Four radio-opaque markers were placed on the abdomen of patients who underwent fluoroscopic imaging of the diaphragm. The coordinates of the markers served as input variables and the position of the diaphragm served as the output variable. PLS resulted in lower prediction errors compared with standard multiple linear regression (MLR). The performance of the feedback control system depends on the system dynamics and dead time (delay between the initiation and execution of the control action). While the dynamics of the system can be inverted in a feedback control system, the dead time cannot be inverted. To overcome the dead time of the system, we propose a predictive feedback control system by incorporating forward prediction using least-mean-square (LMS) and recursive least square (RLS) filtering into the couch-based control system. Motion data were obtained using a skin-based marker. The proposed predictive feedback control system was benchmarked against pure feedback control (no forward prediction) and resulted in a significant performance gain. Finally, we combined the PLS inference model and the predictive feedback control to evaluate the overall performance of the </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4497459','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4497459">Modeling the relativistic runaway electron avalanche and the feedback mechanism with GEANT4</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Skeltved, Alexander Broberg; Østgaard, Nikolai; Carlson, Brant; Gjesteland, Thomas; Celestin, Sebastien 2014-01-01 This paper presents the first study that uses the GEometry ANd Tracking 4 (GEANT4) toolkit to do quantitative comparisons with other modeling results related to the production of terrestrial gamma ray flashes and high-energy particle emission from thunderstorms. We will study the relativistic runaway electron avalanche (RREA) and the relativistic feedback process, as well as the production of bremsstrahlung photons from runaway electrons. The Monte Carlo simulations take into account the effects of electron ionization, electron by electron (Møller), and electron by positron (Bhabha) scattering as well as the bremsstrahlung process and pair production, in the 250 eV to 100 GeV energy range. Our results indicate that the multiplication of electrons during the development of RREAs and under the influence of feedback are consistent with previous estimates. This is important to validate GEANT4 as a tool to model RREAs and feedback in homogeneous electric fields. We also determine the ratio of bremsstrahlung photons to energetic electrons Nγ/Ne. We then show that the ratio has a dependence on the electric field, which can be expressed by the avalanche time τ(E) and the bremsstrahlung coefficient α(ε). In addition, we present comparisons of GEANT4 simulations performed with a “standard” and a “low-energy” physics list both validated in the 1 keV to 100 GeV energy range. This comparison shows that the choice of physics list used in GEANT4 simulations has a significant effect on the results. Key Points Testing the feedback mechanism with GEANT4 Validating the GEANT4 programming toolkit Study the ratio of bremsstrahlung photons to electrons at TGF source altitude PMID:26167437 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26453020','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26453020">Modeling and control of non-square MIMO system using relay feedback.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Kalpana, D; Thyagarajan, T; Gokulraj, N 2015-11-01 This paper proposes a systematic approach for the modeling and control of non-square MIMO systems in time domain using relay feedback. Conventionally, modeling, selection of the control configuration and controller design of non-square MIMO systems are performed using input/output information of direct loop, while the output of undesired responses that bears valuable information on interaction among the loops are not considered. However, in this paper, the undesired response obtained from relay feedback test is also taken into consideration to extract the information about the interaction between the loops. The studies are performed on an Air Path Scheme of Turbocharged Diesel Engine (APSTDE) model, which is a typical non-square MIMO system, with input and output variables being 3 and 2 respectively. From the relay test response, the generalized analytical expressions are derived and these analytical expressions are used to estimate unknown system parameters and also to evaluate interaction measures. The interaction is analyzed by using Block Relative Gain (BRG) method. The model thus identified is later used to design appropriate controller to carry out closed loop studies. Closed loop simulation studies were performed for both servo and regulatory operations. Integral of Squared Error (ISE) performance criterion is employed to quantitatively evaluate performance of the proposed scheme. The usefulness of the proposed method is demonstrated on a lab-scale Two-Tank Cylindrical Interacting System (TTCIS), which is configured as a non-square system. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18490793','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18490793">The motivating role of positive feedback in sport and physical education: evidence for a motivational model.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Mouratidis, Athanasios; Vansteenkiste, Maarten; Lens, Willy; Sideridis, Georgios 2008-04-01 Based on self-determination theory (Deci & Ryan, 2000), an experimental study with middle school students participating in a physical education task and a correlational study with highly talented sport students investigated the motivating role of positive competence feedback on participants' well-being, performance, and intention to participate. In Study 1, structural equation modeling favored the hypothesized motivational model, in which, after controlling for pretask perceived competence and competence valuation, feedback positively predicted competence satisfaction, which in turn predicted higher levels of vitality and greater intentions to participate, through the mediation of autonomous motivation. No effects on performance were found. Study 2 further showed that autonomous motivation mediated the relation between competence satisfaction and well-being, whereas a motivation mediated the negative relation between competence satisfaction and ill-being and rated performance. The discussion focuses on the motivational role of competence feedback in sports and physical education settings. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=time+AND+dilation&pg=3&id=EJ366676','ERIC'); return false;" href="https://eric.ed.gov/?q=time+AND+dilation&pg=3&id=EJ366676">Feedback in Action--The Mechanism of the Iris.</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Pingnet, B.; And Others 1988-01-01 Describes two demonstration experiments. Outlines a demonstration of the general principle of positive and negative feedback and the influence of time delays in feedback circuits. Elucidates the principle of negative feedback with a model of the iris of the eye. Emphasizes the importance of feedback in biological systems. (CW) </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1240921-relationship-between-interannual-long-term-cloud-feedbacks','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1240921-relationship-between-interannual-long-term-cloud-feedbacks">The relationship between interannual and long-term cloud feedbacks</a> <a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a> Zhou, Chen; Zelinka, Mark D.; Dessler, Andrew E.; ... 2015-12-11 The analyses of Coupled Model Intercomparison Project phase 5 simulations suggest that climate models with more positive cloud feedback in response to interannual climate fluctuations also have more positive cloud feedback in response to long-term global warming. Ensemble mean vertical profiles of cloud change in response to interannual and long-term surface warming are similar, and the ensemble mean cloud feedback is positive on both timescales. However, the average long-term cloud feedback is smaller than the interannual cloud feedback, likely due to differences in surface warming pattern on the two timescales. Low cloud cover (LCC) change in response to interannual andmore » long-term global surface warming is found to be well correlated across models and explains over half of the covariance between interannual and long-term cloud feedback. In conclusion, the intermodel correlation of LCC across timescales likely results from model-specific sensitivities of LCC to sea surface warming.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003SPIE.5114..268T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003SPIE.5114..268T">Feedback coupling in dynamical systems</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Trimper, Steffen; Zabrocki, Knud 2003-05-01 Different evolution models are considered with feedback-couplings. In particular, we study the Lotka-Volterra system under the influence of a cumulative term, the Ginzburg-Landau model with a convolution memory term and chemical rate equations with time delay. The memory leads to a modified dynamical behavior. In case of a positive coupling the generalized Lotka-Volterra system exhibits a maximum gain achieved after a finite time, but the population will die out in the long time limit. In the opposite case, the time evolution is terminated in a crash. Due to the nonlinear feedback coupling the two branches of a bistable model are controlled by the the strength and the sign of the memory. For a negative coupling the system is able to switch over between both branches of the stationary solution. The dynamics of the system is further controlled by the initial condition. The diffusion-limited reaction is likewise studied in case the reacting entities are not available simultaneously. Whereas for an external feedback the dynamics is altered, but the stationary solution remain unchanged, a self-organized internal feedback leads to a time persistent solution. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004AGUFM.A23B0797A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004AGUFM.A23B0797A">Polar Amplification of Global Warming in Models Without Ice-Albedo Feedbacks</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Alexeev, V. A.; Langen, P. L. 2004-12-01 Non-ice-albedo feedback mechanisms leading to polar amplification, as reported by Alexeev (2003), are explored in three aquaplanet climate model systems of different complexity. We analyze this pattern using three different "ghost forcing" experiments (Hansen et al, 1997). In the first one we uniformly add 4W/m2 to the oceanic mixed layer in order to roughly simulate a 2xCO2 forcing at the surface. The second forcing, of the same magnitude, is applied only within the tropics and the third forcing is applied only polewards of 30 degrees (north and south). It turns out that our systems' equilibrium responses are linear with respect to these forcings. Surprisingly, the response to the tropical-only forcing is essentially non-local with quite significant warming at higher latitudes. The response to the high-latitude-only forcing is more local and has higher amplitude near the poles. Our explanation of the polar amplification obtained in the uniform forcing experiment is therefore two-fold. Firstly, the tropics are much more difficult to warm because of the higher sensitivity of the surface budget to SST changes at higher temperatures. Secondly, any extra heat deposited in the tropics is not easily radiated to outer space because of the high opaqueness of the tropical atmosphere. The energy, most of which is latent, needs to be redistributed by transports to the extra-tropics. Consequently, the tropical "ghost forcing" results in an essentially non-local response, while the extra-tropical one yields a more localized response, because the energy in the atmosphere cannot propagate effectively equator-wards from high latitudes. The paper deals with these mechanisms in three climate model systems with no ice-albedo feedbacks - an EBM and two different GCMs - one with cloud feedbacks and the other with cloud feedbacks excluded. References. Alexeev, V.A., (2003) Sensitivity to CO2 doubling of an atmospheric GCM coupled to an oceanic mixed layer: a linear analysis. Climate </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3751067','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3751067">Qualitative study about the ways teachers react to feedback from resident evaluations</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> 2013-01-01 Background Currently, one of the main interventions that are widely expected to contribute to teachers’ professional development is confronting teachers with feedback from resident evaluations of their teaching performance. Receiving feedback, however, is a double edged sword. Teachers see themselves confronted with information about themselves and are, at the same time, expected to be role models in the way they respond to feedback. Knowledge about the teachers’ responses could be not only of benefit for their professional development, but also for supporting their role modeling. Therefore, research about professional development should include the way teachers respond to feedback. Method We designed a qualitative study with semi-structured individual conversations about feedback reports, gained from resident evaluations. Two researchers carried out a systematic analysis using qualitative research software. The analysis focused on what happened in the conversations and structured the data in three main themes: conversation process, acceptance and coping strategies. Results The result section describes the conversation patterns and atmosphere. Teachers accepted their results calmly, stating that, although they recognised some points of interest, they could not meet with every standard. Most used coping strategies were explaining the results from their personal beliefs about good teaching and attributing poor results to external factors and good results to themselves. However, some teachers admitted that they had poor results because of the fact that they were not “sharp enough” in their resident group, implying that they did not do their best. Conclusions Our study not only confirms that the effects of feedback depend first and foremost on the recipient but also enlightens the meaning and role of acceptance and being a role model. We think that the results justify the conclusion that teachers who are responsible for the day release programmes in the three </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.A21H3130P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.A21H3130P">The Radiative Forcing Model Intercomparison Project (RFMIP): Assessment and characterization of forcing to enable feedback studies</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Pincus, R.; Stevens, B. B.; Forster, P.; Collins, W.; Ramaswamy, V. 2014-12-01 The Radiative Forcing Model Intercomparison Project (RFMIP): Assessment and characterization of forcing to enable feedback studies An enormous amount of attention has been paid to the diversity of responses in the CMIP and other multi-model ensembles. This diversity is normally interpreted as a distribution in climate sensitivity driven by some distribution of feedback mechanisms. Identification of these feedbacks relies on precise identification of the forcing to which each model is subject, including distinguishing true error from model diversity. The Radiative Forcing Model Intercomparison Project (RFMIP) aims to disentangle the role of forcing from model sensitivity as determinants of varying climate model response by carefully characterizing the radiative forcing to which such models are subject and by coordinating experiments in which it is specified. RFMIP consists of four activities: 1) An assessment of accuracy in flux and forcing calculations for greenhouse gases under past, present, and future climates, using off-line radiative transfer calculations in specified atmospheres with climate model parameterizations and reference models 2) Characterization and assessment of model-specific historical forcing by anthropogenic aerosols, based on coordinated diagnostic output from climate models and off-line radiative transfer calculations with reference models 3) Characterization of model-specific effective radiative forcing, including contributions of model climatology and rapid adjustments, using coordinated climate model integrations and off-line radiative transfer calculations with a single fast model 4) Assessment of climate model response to precisely-characterized radiative forcing over the historical record, including efforts to infer true historical forcing from patterns of response, by direct specification of non-greenhouse-gas forcing in a series of coordinated climate model integrations This talk discusses the rationale for RFMIP, provides an overview </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013MNRAS.431.2513W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013MNRAS.431.2513W">A comparative study of AGN feedback algorithms</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Wurster, J.; Thacker, R. J. 2013-05-01 Modelling active galactic nuclei (AGN) feedback in numerical simulations is both technically and theoretically challenging, with numerous approaches having been published in the literature. We present a study of five distinct approaches to modelling AGN feedback within gravitohydrodynamic simulations of major mergers of Milky Way-sized galaxies. To constrain differences to only be between AGN feedback models, all simulations start from the same initial conditions and use the same star formation algorithm. Most AGN feedback algorithms have five key aspects: the black hole accretion rate, energy feedback rate and method, particle accretion algorithm, black hole advection algorithm and black hole merger algorithm. All models follow different accretion histories, and in some cases, accretion rates differ by up to three orders of magnitude at any given time. We consider models with either thermal or kinetic feedback, with the associated energy deposited locally around the black hole. Each feedback algorithm modifies the region around the black hole to different extents, yielding gas densities and temperatures within r ˜ 200 pc that differ by up to six orders of magnitude at any given time. The particle accretion algorithms usually maintain good agreement between the total mass accreted by dot{M} dt and the total mass of gas particles removed from the simulation, although not all algorithms guarantee this to be true. The black hole advection algorithms dampen inappropriate dragging of the black holes by two-body interactions. Advecting the black hole a limited distance based upon local mass distributions has many desirably properties, such as avoiding large artificial jumps and allowing the possibility of the black hole remaining in a gas void. Lastly, two black holes instantly merge when given criteria are met, and we find a range of merger times for different criteria. This is important since the AGN feedback rate changes across the merger in a way that is dependent </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active">11</li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active">12</li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21711354','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21711354">Age, sex and individual differences in punishment sensitivity: factors influencing the feedback-related negativity.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Santesso, Diane L; Dzyundzyak, Angela; Segalowitz, Sidney J 2011-11-01 The anterior cingulate cortex (ACC) is central to evaluating performance outcomes and has been linked to individual differences in affective responses to feedback. We used electrophysiological source localization to examine the feedback-related negativity (FRN) and related ACC activity during a gambling task in relation to punishment and reward sensitivity among 16- to 17-year-old adolescents (n=20) and 18- to 29-year-old adults (n=30). The FRN was larger for monetary loss compared to win feedback and larger for high relative to low monetary value feedback, with no age differences in the FRN for win or loss feedback. Self-reported sensitivity to punishment accounted for unique variance (over sex and sensitivity to reward) in FRNs, with higher scores relating to larger FRNs and increased rostral ACC activity. These results support the ACC role in experiencing negative performance feedback, especially for individuals highly sensitive to punishment. Copyright © 2011 Society for Psychophysiological Research. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24808008','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24808008">Feedback control by online learning an inverse model.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Waegeman, Tim; Wyffels, Francis; Schrauwen, Francis 2012-10-01 A model, predictor, or error estimator is often used by a feedback controller to control a plant. Creating such a model is difficult when the plant exhibits nonlinear behavior. In this paper, a novel online learning control framework is proposed that does not require explicit knowledge about the plant. This framework uses two learning modules, one for creating an inverse model, and the other for actually controlling the plant. Except for their inputs, they are identical. The inverse model learns by the exploration performed by the not yet fully trained controller, while the actual controller is based on the currently learned model. The proposed framework allows fast online learning of an accurate controller. The controller can be applied on a broad range of tasks with different dynamic characteristics. We validate this claim by applying our control framework on several control tasks: 1) the heating tank problem (slow nonlinear dynamics); 2) flight pitch control (slow linear dynamics); and 3) the balancing problem of a double inverted pendulum (fast linear and nonlinear dynamics). The results of these experiments show that fast learning and accurate control can be achieved. Furthermore, a comparison is made with some classical control approaches, and observations concerning convergence and stability are made. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AtmEn.115..499M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AtmEn.115..499M">Feedbacks between air pollution and weather, part 2: Effects on chemistry</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Makar, P. A.; Gong, W.; Hogrefe, C.; Zhang, Y.; Curci, G.; Žabkar, R.; Milbrandt, J.; Im, U.; Balzarini, A.; Baró, R.; Bianconi, R.; Cheung, P.; Forkel, R.; Gravel, S.; Hirtl, M.; Honzak, L.; Hou, A.; Jiménez-Guerrero, P.; Langer, M.; Moran, M. D.; Pabla, B.; Pérez, J. L.; Pirovano, G.; San José, R.; Tuccella, P.; Werhahn, J.; Zhang, J.; Galmarini, S. 2015-08-01 Fully-coupled air-quality models running in ;feedback; and ;no-feedback; configurations were compared against each other and observation network data as part of Phase 2 of the Air Quality Model Evaluation International Initiative. In the ;no-feedback; mode, interactions between meteorology and chemistry through the aerosol direct and indirect effects were disabled, with the models reverting to climatologies of aerosol properties, or a no-aerosol weather simulation, while in the ;feedback; mode, the model-generated aerosols were allowed to modify the models' radiative transfer and/or cloud formation processes. Annual simulations with and without feedbacks were conducted for domains in North America for the years 2006 and 2010, and for Europe for the year 2010. Comparisons against observations via annual statistics show model-to-model variation in performance is greater than the within-model variation associated with feedbacks. However, during the summer and during intense emission events such as the Russian forest fires of 2010, feedbacks have a significant impact on the chemical predictions of the models. The aerosol indirect effect was usually found to dominate feedbacks compared to the direct effect. The impacts of direct and indirect effects were often shown to be in competition, for predictions of ozone, particulate matter and other species. Feedbacks were shown to result in local and regional shifts of ozone-forming chemical regime, between NOx- and VOC-limited environments. Feedbacks were shown to have a substantial influence on biogenic hydrocarbon emissions and concentrations: North American simulations incorporating both feedbacks resulted in summer average isoprene concentration decreases of up to 10%, while European direct effect simulations during the Russian forest fire period resulted in grid average isoprene changes of -5 to +12.5%. The atmospheric transport and chemistry of large emitting sources such as plumes from forest fires and large cities </li> <li> <a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060043977&hterms=artificial+intelligence+improve+diagnosis&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dartificial%2Bintelligence%2Bimprove%2Bdiagnosis','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060043977&hterms=artificial+intelligence+improve+diagnosis&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dartificial%2Bintelligence%2Bimprove%2Bdiagnosis">Model compilation for real-time planning and diagnosis with feedback</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Barrett, Anthony 2005-01-01 This paper describes MEXEC, an implemented micro executive that compiles a device model that can have feedback into a structure for subsequent evaluation. This system computes both the most likely current device mode from n sets of sensor measurements and the n-1 step reconfiguration plan that is most likely to result in reaching a target mode - if such a plan exists. A user tunes the system by increasing n to improve system capability at the cost of real-time performance. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26213674','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26213674">On the nature of the sea ice albedo feedback in simple models.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Moon, W; Wettlaufer, J S 2014-08-01 We examine the nature of the ice-albedo feedback in a long-standing approach used in the dynamic-thermodynamic modeling of sea ice. The central issue examined is how the evolution of the ice area is treated when modeling a partial ice cover using a two-category-thickness scheme; thin sea ice and open water in one category and "thick" sea ice in the second. The problem with the scheme is that the area evolution is handled in a manner that violates the basic rules of calculus, which leads to a neglected area evolution term that is equivalent to neglecting a leading-order latent heat flux. We demonstrate the consequences by constructing energy balance models with a fractional ice cover and studying them under the influence of increased radiative forcing. It is shown that the neglected flux is particularly important in a decaying ice cover approaching the transitions to seasonal or ice-free conditions. Clearly, a mishandling of the evolution of the ice area has leading-order effects on the ice-albedo feedback. Accordingly, it may be of considerable importance to reexamine the relevant climate model schemes and to begin the process of converting them to fully resolve the sea ice thickness distribution in a manner such as remapping, which does not in principle suffer from the pathology we describe. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4508964','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4508964">On the nature of the sea ice albedo feedback in simple models</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Moon, W; Wettlaufer, J S 2014-01-01 We examine the nature of the ice-albedo feedback in a long-standing approach used in the dynamic-thermodynamic modeling of sea ice. The central issue examined is how the evolution of the ice area is treated when modeling a partial ice cover using a two-category-thickness scheme; thin sea ice and open water in one category and “thick” sea ice in the second. The problem with the scheme is that the area evolution is handled in a manner that violates the basic rules of calculus, which leads to a neglected area evolution term that is equivalent to neglecting a leading-order latent heat flux. We demonstrate the consequences by constructing energy balance models with a fractional ice cover and studying them under the influence of increased radiative forcing. It is shown that the neglected flux is particularly important in a decaying ice cover approaching the transitions to seasonal or ice-free conditions. Clearly, a mishandling of the evolution of the ice area has leading-order effects on the ice-albedo feedback. Accordingly, it may be of considerable importance to reexamine the relevant climate model schemes and to begin the process of converting them to fully resolve the sea ice thickness distribution in a manner such as remapping, which does not in principle suffer from the pathology we describe. PMID:26213674 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24082126','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24082126">Stratospheric water vapor feedback.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Dessler, A E; Schoeberl, M R; Wang, T; Davis, S M; Rosenlof, K H 2013-11-05 We show here that stratospheric water vapor variations play an important role in the evolution of our climate. This comes from analysis of observations showing that stratospheric water vapor increases with tropospheric temperature, implying the existence of a stratospheric water vapor feedback. We estimate the strength of this feedback in a chemistry-climate model to be +0.3 W/(m(2)⋅K), which would be a significant contributor to the overall climate sensitivity. One-third of this feedback comes from increases in water vapor entering the stratosphere through the tropical tropopause layer, with the rest coming from increases in water vapor entering through the extratropical tropopause. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3831493','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3831493">Stratospheric water vapor feedback</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Dessler, A. E.; Schoeberl, M. R.; Wang, T.; Davis, S. M.; Rosenlof, K. H. 2013-01-01 We show here that stratospheric water vapor variations play an important role in the evolution of our climate. This comes from analysis of observations showing that stratospheric water vapor increases with tropospheric temperature, implying the existence of a stratospheric water vapor feedback. We estimate the strength of this feedback in a chemistry–climate model to be +0.3 W/(m2⋅K), which would be a significant contributor to the overall climate sensitivity. One-third of this feedback comes from increases in water vapor entering the stratosphere through the tropical tropopause layer, with the rest coming from increases in water vapor entering through the extratropical tropopause. PMID:24082126 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5253555','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5253555">Effectiveness of a lumbopelvic monitor and feedback device to change postural behaviour: a protocol for the ELF cluster randomised controlled trial</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Milosavljevic, Stephan 2017-01-01 Introduction Low back pain (LBP) is the most common, costly and disabling musculoskeletal disorder worldwide, and is prevalent in healthcare workers. Posture is a modifiable risk factor for LBP shown to reduce the prevalence of LBP. Our feasibility research suggests that postural feedback might help healthcare workers avoid hazardous postures. The Effectiveness of Lumbopelvic Feedback (ELF) trial will investigate the extent to which postural monitor and feedback (PMF) can reduce exposure to hazardous posture associated with LBP. Methods This is a participant-blinded, randomised controlled trial with blocked cluster random allocation. Participants will include volunteer healthcare workers recruited from aged care institutions and hospitals. A postural monitoring and feedback device will monitor and record lumbopelvic forward bending posture, and provide audio feedback whenever the user sustains a lumbopelvic forward bending posture that exceeds predefined thresholds. The primary outcome measure will be postural behaviour (exceeding thresholds). Secondary outcome measures will be incidence of LBP, participant-reported disability and adherence. Following baseline assessment, we will randomly assign participants to 1 of 2 intervention arms: a feedback group and a no-feedback control group. We will compare between-group differences of changes in postural behaviour by using a repeated measures mixed-effect model analysis of covariance (ANCOVA) at 6 weeks. Postural behaviour baseline scores, work-related psychosocial factors and disability scores will be input as covariates into the statistical models. We will use logistic mixed model analysis and Cox's proportional hazards for assessing the effect of a PMF on LBP incidence between groups. Discussion Posture is a modifiable risk factor for low back disorders. Findings from the ELF trial will inform the design of future clinical trials assessing the effectiveness of wearable technology on minimising hazardous posture </li> <li> <a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED509945.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED509945.pdf">Feedback Processes in Multimedia Language Learning Software</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Kartal, Erdogan 2010-01-01 Feedback has been one of the important elements of learning and teaching theories and still pervades the literature and instructional models, especially computer and web-based ones. However, the mechanisms about feedback dominating the fundamentals of all the instructional models designed for self-learning have changed considerably with the… </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMGC44B..02K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMGC44B..02K">Quantifying the ice-albedo feedback through decoupling</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Kravitz, B.; Rasch, P. J. 2017-12-01 The ice-albedo feedback involves numerous individual components, whereby warming induces sea ice melt, inducing reduced surface albedo, inducing increased surface shortwave absorption, causing further warming. Here we attempt to quantify the sea ice albedo feedback using an analogue of the "partial radiative perturbation" method, but where the governing mechanisms are directly decoupled in a climate model. As an example, we can isolate the insulating effects of sea ice on surface energy and moisture fluxes by allowing sea ice thickness to change but fixing Arctic surface albedo, or vice versa. Here we present results from such idealized simulations using the Community Earth System Model in which individual components are successively fixed, effectively decoupling the ice-albedo feedback loop. We isolate the different components of this feedback, including temperature change, sea ice extent/thickness, and air-sea exchange of heat and moisture. We explore the interactions between these different components, as well as the strengths of the total feedback in the decoupled feedback loop, to quantify contributions from individual pieces. We also quantify the non-additivity of the effects of the components as a means of investigating the dominant sources of nonlinearity in the ice-albedo feedback. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AIPC.1559..333M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AIPC.1559..333M">Modeling of testosterone regulation by pulse-modulated feedback: An experimental data study</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Mattsson, Per; Medvedev, Alexander 2013-10-01 The continuous part of a hybrid (pulse-modulated) model of testosterone feedback regulation is extended with infinite-dimensional and nonlinear dynamics, to better explain the testosterone concentration profiles observed in clinical data. A linear least-squares based optimization algorithm is developed for the purpose of detecting impulses of gonadotropin-realsing hormone from measured concentration of luteinizing hormone. The parameters in the model are estimated from hormone concentration measured in human males, and simulation results from the full closed-loop system are provided. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=deep+AND+processing+AND+time&pg=4&id=ED266766','ERIC'); return false;" href="https://eric.ed.gov/?q=deep+AND+processing+AND+time&pg=4&id=ED266766">Levels of Questioning and Forms of Feedback: Instructional Factors in Courseware Design.</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Merrill, John High and low level questions as determined by a panel of evaluators were combined with corrective feedback and attribute isolation feedback to form four versions of a computer-based science lesson. The sample consisted of 154 high school chemistry students in a suburban high school. The primary hypothesis was that students who received high level… </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018GMD....11...77S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018GMD....11...77S">The Cloud Feedback Model Intercomparison Project Observational Simulator Package: Version 2</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Swales, Dustin J.; Pincus, Robert; Bodas-Salcedo, Alejandro 2018-01-01 The Cloud Feedback Model Intercomparison Project Observational Simulator Package (COSP) gathers together a collection of observation proxies or <q>satellite simulators</q> that translate model-simulated cloud properties to synthetic observations as would be obtained by a range of satellite observing systems. This paper introduces COSP2, an evolution focusing on more explicit and consistent separation between host model, coupling infrastructure, and individual observing proxies. Revisions also enhance flexibility by allowing for model-specific representation of sub-grid-scale cloudiness, provide greater clarity by clearly separating tasks, support greater use of shared code and data including shared inputs across simulators, and follow more uniform software standards to simplify implementation across a wide range of platforms. The complete package including a testing suite is freely available. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29222625','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29222625">Using Patient Feedback to Optimize the Design of a Certolizumab Pegol Electromechanical Self-Injection Device: Insights from Human Factors Studies.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Domańska, Barbara; Stumpp, Oliver; Poon, Steven; Oray, Serkan; Mountian, Irina; Pichon, Clovis 2018-01-01 We incorporated patient feedback from human factors studies (HFS) in the patient-centric design and validation of ava ® , an electromechanical device (e-Device) for self-injecting the anti-tumor necrosis factor certolizumab pegol (CZP). Healthcare professionals, caregivers, healthy volunteers, and patients with rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, or Crohn's disease participated in 11 formative HFS to optimize the e-Device design through intended user feedback; nine studies involved simulated injections. Formative participant questionnaire feedback was collected following e-Device prototype handling. Validation HFS (one EU study and one US study) assessed the safe and effective setup and use of the e-Device using 22 predefined critical tasks. Task outcomes were categorized as "failures" if participants did not succeed within three attempts. Two hundred eighty-three participants entered formative (163) and validation (120) HFS; 260 participants performed one or more simulated e-Device self-injections. Design changes following formative HFS included alterations to buttons and the graphical user interface screen. All validation HFS participants completed critical tasks necessary for CZP dose delivery, with minimal critical task failures (12 of 572 critical tasks, 2.1%, in the EU study, and 2 of 5310 critical tasks, less than 0.1%, in the US study). CZP e-Device development was guided by intended user feedback through HFS, ensuring the final design addressed patients' needs. In both validation studies, participants successfully performed all critical tasks, demonstrating safe and effective e-Device self-injections. UCB Pharma. Plain language summary available on the journal website. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017MNRAS.465.1682H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017MNRAS.465.1682H">How stellar feedback simultaneously regulates star formation and drives outflows</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Hayward, Christopher C.; Hopkins, Philip F. 2017-02-01 We present an analytic model for how momentum deposition from stellar feedback simultaneously regulates star formation and drives outflows in a turbulent interstellar medium (ISM). Because the ISM is turbulent, a given patch of ISM exhibits sub-patches with a range of surface densities. The high-density patches are 'pushed' by feedback, thereby driving turbulence and self-regulating local star formation. Sufficiently low-density patches, however, are accelerated to above the escape velocity before the region can self-adjust and are thus vented as outflows. When the gas fraction is ≳ 0.3, the ratio of the turbulent velocity dispersion to the circular velocity is sufficiently high that at any given time, of the order of half of the ISM has surface density less than the critical value and thus can be blown out on a dynamical time. The resulting outflows have a mass-loading factor (η ≡ dot{M}_{out}/M_{star }) that is inversely proportional to the gas fraction times the circular velocity. At low gas fractions, the star formation rate needed for local self-regulation, and corresponding turbulent Mach number, declines rapidly; the ISM is 'smoother', and it is actually more difficult to drive winds with large mass-loading factors. Crucially, our model predicts that stellar-feedback-driven outflows should be suppressed at z ≲ 1 in M⋆ ≳ 1010 M⊙ galaxies. This mechanism allows massive galaxies to exhibit violent outflows at high redshifts and then 'shut down' those outflows at late times, thereby enabling the formation of a smooth, extended thin stellar disc. We provide simple fitting functions for η that should be useful for sub-resolution and semi-analytic models. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018MS%26E..320a2013I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018MS%26E..320a2013I">An Optimization of Manufacturing Systems using a Feedback Control Scheduling Model</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Ikome, John M.; Kanakana, Grace M. 2018-03-01 In complex production system that involves multiple process, unplanned disruption often turn to make the entire production system vulnerable to a number of problems which leads to customer’s dissatisfaction. However, this problem has been an ongoing problem that requires a research and methods to streamline the entire process or develop a model that will address it, in contrast to this, we have developed a feedback scheduling model that can minimize some of this problem and after a number of experiment, it shows that some of this problems can be eliminated if the correct remedial actions are implemented on time. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28182558','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28182558">Model-Based Adaptive Event-Triggered Control of Strict-Feedback Nonlinear Systems.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Li, Yuan-Xin; Yang, Guang-Hong 2018-04-01 This paper is concerned with the adaptive event-triggered control problem of nonlinear continuous-time systems in strict-feedback form. By using the event-sampled neural network (NN) to approximate the unknown nonlinear function, an adaptive model and an associated event-triggered controller are designed by exploiting the backstepping method. In the proposed method, the feedback signals and the NN weights are aperiodically updated only when the event-triggered condition is violated. A positive lower bound on the minimum intersample time is guaranteed to avoid accumulation point. The closed-loop stability of the resulting nonlinear impulsive dynamical system is rigorously proved via Lyapunov analysis under an adaptive event sampling condition. In comparing with the traditional adaptive backstepping design with a fixed sample period, the event-triggered method samples the state and updates the NN weights only when it is necessary. Therefore, the number of transmissions can be significantly reduced. Finally, two simulation examples are presented to show the effectiveness of the proposed control method. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=information+AND+processing+AND+model+AND+recall&pg=7&id=EJ523269','ERIC'); return false;" href="https://eric.ed.gov/?q=information+AND+processing+AND+model+AND+recall&pg=7&id=EJ523269">Effects of OCR Errors on Ranking and Feedback Using the Vector Space Model.</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Taghva, Kazem; And Others 1996-01-01 Reports on the performance of the vector space model in the presence of OCR (optical character recognition) errors in information retrieval. Highlights include precision and recall, a full-text test collection, smart vector representation, impact of weighting parameters, ranking variability, and the effect of relevance feedback. (Author/LRW) </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMGC22A..07H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMGC22A..07H">Building sector feedbacks lead to increased energy demands</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Hartin, C.; Link, R. P.; Patel, P.; Horowitz, R.; Clarke, L.; Mundra, A. 2017-12-01 Typically in human-earth system modeling studies, feedbacks between the earth and human systems are analyzed by passing information between independent models, leading to data errors and poor reproducibility. In this study we explore the two-way feedbacks between the human and earth systems in the building sector of GCAM, an integrated assessment model and, its fully-integrated climate component, Hector. While there is a general agreement in the literature that increasing temperatures will increase cooling energy demands and decrease heating energy demands, there has been no fully-coupled analysis of this dynamic that would, for example, account for the feedbacks on hydrofluorocarbons from increased cooling demands. Using a statistical relationship between global mean temperature change and heating and cooling degree days, we find that the feedbacks on hydrofluorocarbons lead to an increase in global mean temperature of between 0.16 to 0.27 °C in 2100. Demands for electricity increase by about 10% in Africa, while demands decrease in Canada by about 3.0% when taking into account these feedbacks. While the feedbacks between building energy demand and global mean temperature are modest by themselves, this study prompts future research on coupled human-earth system feedbacks, in particular in regards to land, water, and other energy infrastructure. </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active">12</li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active">13</li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/EJ1100358.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/EJ1100358.pdf">Student Views on the Value of Feedback</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Marie, Jenny A. 2016-01-01 This paper investigates the value that a sample of students placed on feedback, what they valued it for and the conditions that affected this value judgement. I show that not all students value feedback particularly highly, especially when considered in relation to other factors in their education and when considered for its intrinsic value as… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1354831-feedback-assisted-extension-tokamak-operating-space-low-safety-factor','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1354831-feedback-assisted-extension-tokamak-operating-space-low-safety-factor">Feedback-assisted extension of the tokamak operating space to low safety factor</a> <a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a> Hanson, Jeremy M.; Bialek, James M.; Baruzzo, M.; ... 2014-07-07 Recent DIII-D and RFX-mod experiments have demonstrated stable tokamak operation at very low values of the edge safety factor q( a) near and below 2. The onset of n = 1 resistive wall mode (RWM) kink instabilities leads to a disruptive stability limit, encountered at q( a) = 2 (limiter plasmas) and q 95 = 2 (divertor plasmas). However, passively stable operation can be attained for q( a) and q 95 values as low as 2.2. RWM damping in the q( a) = 2 regime was measured using active MHD spectroscopy. Although consistent with theoretical predictions, the amplitude of themore » damped response does not increase significantly as the q( a) = 2 limit is approached, in contrast with damping measurements made approaching the pressure-driven RWM limit. Applying proportional gain magnetic feedback control of the n = 1 modes has resulted in stabilized operation with q 95 values reaching as low as 1.9 in DIII-D and q( a) reaching 1.55 in RFX-mod. In addition to being consistent with the q( a) = 2 external kink mode stability limit, the unstable modes have growth rates on the order of the characteristic wall eddy-current decay timescale in both devices, and a dominant m = 2 poloidal structure that is consistent with ideal MHD predictions. As a result, the experiments contribute to validating MHD stability theory and demonstrate that a key tokamak stability limit can be overcome with feedback.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1430258','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/1430258">Understanding the tropical cloud feedback from an analysis of the circulation and stability regimes simulated from an upgraded multiscale modeling framework</a> <a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a> Xu, Kuan-Man; Cheng, Anning As revealed from studies using conventional general circulation models (GCMs), the thermodynamic contribution to the tropical cloud feedback dominates the dynamic contribution, but these models have difficulty in simulating the subsidence regimes in the tropics. In this study, we analyze the tropical cloud feedback from a 2 K sea surface temperature (SST) perturbation experiment performed with a multiscale modeling framework (MMF). The MMF explicitly represents cloud processes using 2-D cloud-resolving models with an advanced higher-order turbulence closure in each atmospheric column of the host GCM. We sort the monthly mean cloud properties and cloud radiative effects according to circulation andmore » stability regimes. Here, we find that the regime-sorted dynamic changes dominate the thermodynamic changes in terms of the absolute magnitude. The dynamic changes in the weak subsidence regimes exhibit strong negative cloud feedback due to increases in shallow cumulus and deep clouds while those in strongly convective and moderate-to-strong subsidence regimes have opposite signs, resulting in a small contribution to cloud feedback. On the other hand, the thermodynamic changes are large due to decreases in stratocumulus clouds in the moderate-to-strong subsidence regimes with small opposite changes in the weak subsidence and strongly convective regimes, resulting in a relatively large contribution to positive cloud feedback. The dynamic and thermodynamic changes contribute equally to positive cloud feedback and are relatively insensitive to stability in the moderate-to-strong subsidence regimes. But they are sensitive to stability changes from the SST increase in convective and weak subsidence regimes. Lastly, these results have implications for interpreting cloud feedback mechanisms.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1430258-understanding-tropical-cloud-feedback-from-analysis-circulation-stability-regimes-simulated-from-upgraded-multiscale-modeling-framework','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1430258-understanding-tropical-cloud-feedback-from-analysis-circulation-stability-regimes-simulated-from-upgraded-multiscale-modeling-framework">Understanding the tropical cloud feedback from an analysis of the circulation and stability regimes simulated from an upgraded multiscale modeling framework</a> <a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a> Xu, Kuan-Man; Cheng, Anning 2016-11-15 As revealed from studies using conventional general circulation models (GCMs), the thermodynamic contribution to the tropical cloud feedback dominates the dynamic contribution, but these models have difficulty in simulating the subsidence regimes in the tropics. In this study, we analyze the tropical cloud feedback from a 2 K sea surface temperature (SST) perturbation experiment performed with a multiscale modeling framework (MMF). The MMF explicitly represents cloud processes using 2-D cloud-resolving models with an advanced higher-order turbulence closure in each atmospheric column of the host GCM. We sort the monthly mean cloud properties and cloud radiative effects according to circulation andmore » stability regimes. Here, we find that the regime-sorted dynamic changes dominate the thermodynamic changes in terms of the absolute magnitude. The dynamic changes in the weak subsidence regimes exhibit strong negative cloud feedback due to increases in shallow cumulus and deep clouds while those in strongly convective and moderate-to-strong subsidence regimes have opposite signs, resulting in a small contribution to cloud feedback. On the other hand, the thermodynamic changes are large due to decreases in stratocumulus clouds in the moderate-to-strong subsidence regimes with small opposite changes in the weak subsidence and strongly convective regimes, resulting in a relatively large contribution to positive cloud feedback. The dynamic and thermodynamic changes contribute equally to positive cloud feedback and are relatively insensitive to stability in the moderate-to-strong subsidence regimes. But they are sensitive to stability changes from the SST increase in convective and weak subsidence regimes. Lastly, these results have implications for interpreting cloud feedback mechanisms.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25202845','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25202845">Auditory feedback improves heart rate moderation during moderate-intensity exercise.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Shaykevich, Alex; Grove, J Robert; Jackson, Ben; Landers, Grant J; Dimmock, James 2015-05-01 The objective of this study is to determine whether exposure to automated HR feedback can produce improvements in the ability to regulate HR during moderate-intensity exercise and to evaluate the persistence of these improvements after feedback is removed. Twenty healthy adults performed 10 indoor exercise sessions on cycle ergometers over 5 wk after a twice-weekly schedule. During these sessions (FB), participants received auditory feedback designed to maintain HR within a personalized, moderate-intensity training zone between 70% and 80% of estimated maximum HR. All feedback was delivered via a custom mobile software application. Participants underwent an initial assessment (PREFB) to measure their ability to maintain exercise intensity defined by the training zone without use of feedback. After completing the feedback training, participants performed three additional assessments identical to PREFB at 1 wk (POST1), 2 wk (POST2), and 4 wk (POST3) after their last feedback session. Time in zone (TIZ), defined as the ratio of the time spent within the training zone divided by the overall time of exercise, rate of perceived exertion, instrumental attitudes, and affective attitudes were then evaluated to assess results using two-way, mixed-model ANOVA with sessions and gender as factors. Training with feedback significantly improved TIZ (P < 0.01) compared with PREFB. An absence of significant differences in TIZ between FB, POST1, POST2, and POST3 (P ≥ 0.35) indicated that these improvements were maintained after feedback was removed. No significant differences in rate of perceived exertion (P ≥ 0.40) or attitude measures (P ≥ 0.30) were observed. Auditory biofeedback is an effective mechanism for entraining HR regulation during moderate-intensity exercise in healthy adults. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19910057048&hterms=air+plant&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dair%2Bplant','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19910057048&hterms=air+plant&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dair%2Bplant">Feedback linearization for control of air breathing engines</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Phillips, Stephen; Mattern, Duane 1991-01-01 The method of feedback linearization for control of the nonlinear nozzle and compressor components of an air breathing engine is presented. This method overcomes the need for a large number of scheduling variables and operating points to accurately model highly nonlinear plants. Feedback linearization also results in linear closed loop system performance simplifying subsequent control design. Feedback linearization is used for the nonlinear partial engine model and performance is verified through simulation. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1376324','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/1376324">The BGC Feedbacks Scientific Focus Area 2016 Annual Progress Report</a> <a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a> Hoffman, Forrest M.; Riley, William J.; Randerson, James T. 2016-06-01 The BGC Feedbacks Project will identify and quantify the feedbacks between biogeochemical cycles and the climate system, and quantify and reduce the uncertainties in Earth System Models (ESMs) associated with those feedbacks. The BGC Feedbacks Project will contribute to the integration of the experimental and modeling science communities, providing researchers with new tools to compare measurements and models, thereby enabling DOE to contribute more effectively to future climate assessments by the U.S. Global Change Research Program (USGCRP) and the Intergovernmental Panel on Climate Change (IPCC). </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=Mammalian&pg=5&id=EJ356054','ERIC'); return false;" href="https://eric.ed.gov/?q=Mammalian&pg=5&id=EJ356054">The Inversion of Sensory Processing by Feedback Pathways: A Model of Visual Cognitive Functions.</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Harth, E.; And Others 1987-01-01 Explains the hierarchic structure of the mammalian visual system. Proposes a model in which feedback pathways serve to modify sensory stimuli in ways that enhance and complete sensory input patterns. Investigates the functioning of the system through computer simulations. (ML) </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1438795','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/1438795">Sources of Intermodel Spread in the Lapse Rate and Water Vapor Feedbacks</a> <a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a> Po-Chedley, Stephen; Armour, Kyle C.; Bitz, Cecilia M. Sources of intermodel differences in the global lapse rate (LR) and water vapor (WV) feedbacks are assessed using CO 2 forcing simulations from 28 general circulation models. Tropical surface warming leads to significant warming and moistening in the tropical and extratropical upper troposphere, signifying a nonlocal, tropical influence on extratropical radiation and feedbacks. Model spread in the locally defined LR and WV feedbacks is pronounced in the Southern Ocean because of large-scale ocean upwelling, which reduces surface warming and decouples the surface from the tropospheric response. The magnitude of local extratropical feedbacks across models and over time is well characterizedmore » using the ratio of tropical to extratropical surface warming. It is shown that model differences in locally defined LR and WV feedbacks, particularly over the southern extratropics, drive model variability in the global feedbacks. The cross-model correlation between the global LR and WV feedbacks therefore does not arise from their covariation in the tropics, but rather from the pattern of warming exerting a common control on extratropical feedback responses. Because local feedbacks over the Southern Hemisphere are an important contributor to the global feedback, the partitioning of surface warming between the tropics and the southern extratropics is a key determinant of the spread in the global LR and WV feedbacks. It is also shown that model Antarctic sea ice climatology influences sea ice area changes and southern extratropical surface warming. In conclusion, as a result, model discrepancies in climatological Antarctic sea ice area have a significant impact on the intermodel spread of the global LR and WV feedbacks.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1438795-sources-intermodel-spread-lapse-rate-water-vapor-feedbacks','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1438795-sources-intermodel-spread-lapse-rate-water-vapor-feedbacks">Sources of Intermodel Spread in the Lapse Rate and Water Vapor Feedbacks</a> <a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a> Po-Chedley, Stephen; Armour, Kyle C.; Bitz, Cecilia M.; ... 2018-03-23 Sources of intermodel differences in the global lapse rate (LR) and water vapor (WV) feedbacks are assessed using CO 2 forcing simulations from 28 general circulation models. Tropical surface warming leads to significant warming and moistening in the tropical and extratropical upper troposphere, signifying a nonlocal, tropical influence on extratropical radiation and feedbacks. Model spread in the locally defined LR and WV feedbacks is pronounced in the Southern Ocean because of large-scale ocean upwelling, which reduces surface warming and decouples the surface from the tropospheric response. The magnitude of local extratropical feedbacks across models and over time is well characterizedmore » using the ratio of tropical to extratropical surface warming. It is shown that model differences in locally defined LR and WV feedbacks, particularly over the southern extratropics, drive model variability in the global feedbacks. The cross-model correlation between the global LR and WV feedbacks therefore does not arise from their covariation in the tropics, but rather from the pattern of warming exerting a common control on extratropical feedback responses. Because local feedbacks over the Southern Hemisphere are an important contributor to the global feedback, the partitioning of surface warming between the tropics and the southern extratropics is a key determinant of the spread in the global LR and WV feedbacks. It is also shown that model Antarctic sea ice climatology influences sea ice area changes and southern extratropical surface warming. In conclusion, as a result, model discrepancies in climatological Antarctic sea ice area have a significant impact on the intermodel spread of the global LR and WV feedbacks.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ESD.....9..507L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ESD.....9..507L">Analytically tractable climate-carbon cycle feedbacks under 21st century anthropogenic forcing</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Lade, Steven J.; Donges, Jonathan F.; Fetzer, Ingo; Anderies, John M.; Beer, Christian; Cornell, Sarah E.; Gasser, Thomas; Norberg, Jon; Richardson, Katherine; Rockström, Johan; Steffen, Will 2018-05-01 Changes to climate-carbon cycle feedbacks may significantly affect the Earth system's response to greenhouse gas emissions. These feedbacks are usually analysed from numerical output of complex and arguably opaque Earth system models. Here, we construct a stylised global climate-carbon cycle model, test its output against comprehensive Earth system models, and investigate the strengths of its climate-carbon cycle feedbacks analytically. The analytical expressions we obtain aid understanding of carbon cycle feedbacks and the operation of the carbon cycle. Specific results include that different feedback formalisms measure fundamentally the same climate-carbon cycle processes; temperature dependence of the solubility pump, biological pump, and CO2 solubility all contribute approximately equally to the ocean climate-carbon feedback; and concentration-carbon feedbacks may be more sensitive to future climate change than climate-carbon feedbacks. Simple models such as that developed here also provide <q>workbenches</q> for simple but mechanistically based explorations of Earth system processes, such as interactions and feedbacks between the planetary boundaries, that are currently too uncertain to be included in comprehensive Earth system models. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=logistic+AND+costs&pg=7&id=EJ827055','ERIC'); return false;" href="https://eric.ed.gov/?q=logistic+AND+costs&pg=7&id=EJ827055">Individual and Situational Factors that Influence the Efficacy of Personalized Feedback Substance Use Interventions for Mandated College Students</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Mun, Eun Young; White, Helene R.; Morgan, Thomas J. 2009-01-01 Little is known about individual and situational factors that moderate the efficacy of personalized feedback interventions (PFIs). Mandated college students (N = 348) were randomly assigned either to a PFI delivered in the context of a brief motivational interview (BMI; n = 180) or to a written PFI only (WF) condition and were followed up at 4… </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMED22A..05S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMED22A..05S">Using Students' Explanatory Models as Sources of Feedback: Conceptualizing Ocean Acidification and Its Impacts</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Sezen-Barrie, A.; Stapleton, M.; Wolfson, J. 2017-12-01 This qualitative study focuses on students evidence-based explanatory models on how ocean acidification impacts oysters. Explanatory models are the crucial components of scientific endeavors as it helps scientists explain how the natural world functions and the reasons for the ways it functions. Moreover, these models assemble individual practices to understand how they work together to reach clear conclusions through scientific investigations. Due to their critical roles in making sense of authentic science, recent studies in science education suggest that these models should be part of the curriculum aligned with new science standards, i.e. Next Generation Science Standards, which stress the importance of engaging students in scientific practices. By collecting data from 400 secondary school students in Maryland, we aim to respond to the question: How can we use secondary school students' explanatory models to provide students with constructive feedback for more comprehensive learning of ocean acidification (the related evidence, causes and impact)? The data were analyzed through discourse analysis method. We highlighted and coded students' inscriptions (e.g., drawings, writings, and representations) that are signs of students' understanding (or lack thereof) of ocean acidification. These signs included explanations of pH levels, drawings of oyster growth, and inclusions of relevant data. The findings showed that the explanatory models can be critical forms of feedback as they reveal a) students' alternative conceptions on how ocean acidification impacts oysters or how acidification works in general; b) students' interpretations of oceans' (non)connectedness to Earth system; c) the choice of scientific representations and their sources; and d) the way students' integrate evidence or data from the investigations. Our work tackles an understanding of one of the most vital signs of modern climatic changes. Recent scientific evidence shows that if the change in ocean </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4422442','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4422442">Feedback Valence Affects Auditory Perceptual Learning Independently of Feedback Probability</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Amitay, Sygal; Moore, David R.; Molloy, Katharine; Halliday, Lorna F. 2015-01-01 Previous studies have suggested that negative feedback is more effective in driving learning than positive feedback. We investigated the effect on learning of providing varying amounts of negative and positive feedback while listeners attempted to discriminate between three identical tones; an impossible task that nevertheless produces robust learning. Four feedback conditions were compared during training: 90% positive feedback or 10% negative feedback informed the participants that they were doing equally well, while 10% positive or 90% negative feedback informed them they were doing equally badly. In all conditions the feedback was random in relation to the listeners’ responses (because the task was to discriminate three identical tones), yet both the valence (negative vs. positive) and the probability of feedback (10% vs. 90%) affected learning. Feedback that informed listeners they were doing badly resulted in better post-training performance than feedback that informed them they were doing well, independent of valence. In addition, positive feedback during training resulted in better post-training performance than negative feedback, but only positive feedback indicating listeners were doing badly on the task resulted in learning. As we have previously speculated, feedback that better reflected the difficulty of the task was more effective in driving learning than feedback that suggested performance was better than it should have been given perceived task difficulty. But contrary to expectations, positive feedback was more effective than negative feedback in driving learning. Feedback thus had two separable effects on learning: feedback valence affected motivation on a subjectively difficult task, and learning occurred only when feedback probability reflected the subjective difficulty. To optimize learning, training programs need to take into consideration both feedback valence and probability. PMID:25946173 </li> <li> <a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110013481','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110013481">Quantifying the Negative Feedback of Vegetation to Greenhouse Warming: A Modeling Approach</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Bounous, L.; Hall, F. G.; Sellers, P. J.; Kumar, A.; Collatz, G. J.; Tucker, C. J.; Imhoff, M. L. 2010-01-01 Several climate models indicate that in a 2 x CO2 environment, temperature and precipitation would increase and runoff would increase faster than precipitation. These models, however, did not allow the vegetation to increase its leaf density as a response to the physiological effects of increased CO2 and consequent changes in climate. Other assessments included these interactions but did not account for the vegetation down-regulation to reduce plant's photosynthetic activity and as such resulted in a weak vegetation negative response. When we combine these interactions in climate simulations with 2 x CO2, the associated increase in precipitation contributes primarily to increase evapotranspiration rather than surface runoff, consistent with observations, and results in an additional cooling effect not fully accounted for in previous simulations with elevated CO2. By accelerating the water cycle, this feedback slows but does not alleviate the projected warming, reducing the land surface warming by 0.6 C. Compared to previous studies, these results imply that long term negative feedback from CO2-induced increases in vegetation density could reduce temperature following a stabilization of CO2 concentration. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22272362','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22272362">Climate effects and feedback structure determining weed population dynamics in a long-term experiment.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Lima, Mauricio; Navarrete, Luis; González-Andujar, José Luis 2012-01-01 Pest control is one of the areas in which population dynamic theory has been successfully applied to solve practical problems. However, the links between population dynamic theory and model construction have been less emphasized in the management and control of weed populations. Most management models of weed population dynamics have emphasized the role of the endogenous process, but the role of exogenous variables such as climate have been ignored in the study of weed populations and their management. Here, we use long-term data (22 years) on two annual weed species from a locality in Central Spain to determine the importance of endogenous and exogenous processes (local and large-scale climate factors). Our modeling study determined two different feedback structures and climate effects in the two weed species analyzed. While Descurainia sophia exhibited a second-order feedback and low climate influence, Veronica hederifolia was characterized by a first-order feedback structure and important effects from temperature and rainfall. Our results strongly suggest the importance of theoretical population dynamics in understanding plant population systems. Moreover, the use of this approach, discerning between the effect of exogenous and endogenous factors, can be fundamental to applying weed management practices in agricultural systems and to controlling invasive weedy species. This is a radical change from most approaches currently used to guide weed and invasive weedy species managements. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3260292','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3260292">Climate Effects and Feedback Structure Determining Weed Population Dynamics in a Long-Term Experiment</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Lima, Mauricio; Navarrete, Luis; González-Andujar, José Luis 2012-01-01 Pest control is one of the areas in which population dynamic theory has been successfully applied to solve practical problems. However, the links between population dynamic theory and model construction have been less emphasized in the management and control of weed populations. Most management models of weed population dynamics have emphasized the role of the endogenous process, but the role of exogenous variables such as climate have been ignored in the study of weed populations and their management. Here, we use long-term data (22 years) on two annual weed species from a locality in Central Spain to determine the importance of endogenous and exogenous processes (local and large-scale climate factors). Our modeling study determined two different feedback structures and climate effects in the two weed species analyzed. While Descurainia sophia exhibited a second-order feedback and low climate influence, Veronica hederifolia was characterized by a first-order feedback structure and important effects from temperature and rainfall. Our results strongly suggest the importance of theoretical population dynamics in understanding plant population systems. Moreover, the use of this approach, discerning between the effect of exogenous and endogenous factors, can be fundamental to applying weed management practices in agricultural systems and to controlling invasive weedy species. This is a radical change from most approaches currently used to guide weed and invasive weedy species managements. PMID:22272362 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21113000','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21113000">Disrupting vagal feedback affects birdsong motor control.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Méndez, Jorge M; Dall'asén, Analía G; Goller, Franz 2010-12-15 Coordination of different motor systems for sound production involves the use of feedback mechanisms. Song production in oscines is a well-established animal model for studying learned vocal behavior. Whereas the online use of auditory feedback has been studied in the songbird model, very little is known about the role of other feedback mechanisms. Auditory feedback is required for the maintenance of stereotyped adult song. In addition, the use of somatosensory feedback to maintain pressure during song has been demonstrated with experimentally induced fluctuations in air sac pressure. Feedback information mediating this response is thought to be routed to the central nervous system via afferent fibers of the vagus nerve. Here, we tested the effects of unilateral vagotomy on the peripheral motor patterns of song production and the acoustic features. Unilateral vagotomy caused a variety of disruptions and alterations to the respiratory pattern of song, some of which affected the acoustic structure of vocalizations. These changes were most pronounced a few days after nerve resection and varied between individuals. In the most extreme cases, the motor gestures of respiration were so severely disrupted that individual song syllables or the song motif were atypically terminated. Acoustic changes also suggest altered use of the two sound generators and upper vocal tract filtering, indicating that the disruption of vagal feedback caused changes to the motor program of all motor systems involved in song production and modification. This evidence for the use of vagal feedback by the song system with disruption of song during the first days after nerve cut provides a contrast to the longer-term effects of auditory feedback disruption. It suggests a significant role for somatosensory feedback that differs from that of auditory feedback. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2992464','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2992464">Disrupting vagal feedback affects birdsong motor control</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Méndez, Jorge M.; Dall'Asén, Analía G.; Goller, Franz 2010-01-01 Coordination of different motor systems for sound production involves the use of feedback mechanisms. Song production in oscines is a well-established animal model for studying learned vocal behavior. Whereas the online use of auditory feedback has been studied in the songbird model, very little is known about the role of other feedback mechanisms. Auditory feedback is required for the maintenance of stereotyped adult song. In addition, the use of somatosensory feedback to maintain pressure during song has been demonstrated with experimentally induced fluctuations in air sac pressure. Feedback information mediating this response is thought to be routed to the central nervous system via afferent fibers of the vagus nerve. Here, we tested the effects of unilateral vagotomy on the peripheral motor patterns of song production and the acoustic features. Unilateral vagotomy caused a variety of disruptions and alterations to the respiratory pattern of song, some of which affected the acoustic structure of vocalizations. These changes were most pronounced a few days after nerve resection and varied between individuals. In the most extreme cases, the motor gestures of respiration were so severely disrupted that individual song syllables or the song motif were atypically terminated. Acoustic changes also suggest altered use of the two sound generators and upper vocal tract filtering, indicating that the disruption of vagal feedback caused changes to the motor program of all motor systems involved in song production and modification. This evidence for the use of vagal feedback by the song system with disruption of song during the first days after nerve cut provides a contrast to the longer-term effects of auditory feedback disruption. It suggests a significant role for somatosensory feedback that differs from that of auditory feedback. PMID:21113000 </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013ESASP.720E...9T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013ESASP.720E...9T">The Robust Software Feedback Model: An Effective Waterfall Model Tailoring for Space SW</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Tipaldi, Massimo; Gotz, Christoph; Ferraguto, Massimo; Troiano, Luigi; Bruenjes, Bernhard 2013-08-01 The selection of the most suitable software life cycle process is of paramount importance in any space SW project. Despite being the preferred choice, the waterfall model is often exposed to some criticism. As matter of fact, its main assumption of moving to a phase only when the preceding one is completed and perfected (and under the demanding SW schedule constraints) is not easily attainable. In this paper, a tailoring of the software waterfall model (named “Robust Software Feedback Model”) is presented. The proposed methodology sorts out these issues by combining a SW waterfall model with a SW prototyping approach. The former is aligned with the SW main production line and is based on the full ECSS-E-ST-40C life-cycle reviews, whereas the latter is carried out in advance versus the main SW streamline (so as to inject its lessons learnt into the main streamline) and is based on a lightweight approach. </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active">13</li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active">14</li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014HESS...18.2141E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014HESS...18.2141E">A prototype framework for models of socio-hydrology: identification of key feedback loops and parameterisation approach</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Elshafei, Y.; Sivapalan, M.; Tonts, M.; Hipsey, M. R. 2014-06-01 It is increasingly acknowledged that, in order to sustainably manage global freshwater resources, it is critical that we better understand the nature of human-hydrology interactions at the broader catchment system scale. Yet to date, a generic conceptual framework for building models of catchment systems that include adequate representation of socioeconomic systems - and the dynamic feedbacks between human and natural systems - has remained elusive. In an attempt to work towards such a model, this paper outlines a generic framework for models of socio-hydrology applicable to agricultural catchments, made up of six key components that combine to form the coupled system dynamics: namely, catchment hydrology, population, economics, environment, socioeconomic sensitivity and collective response. The conceptual framework posits two novel constructs: (i) a composite socioeconomic driving variable, termed the Community Sensitivity state variable, which seeks to capture the perceived level of threat to a community's quality of life, and acts as a key link tying together one of the fundamental feedback loops of the coupled system, and (ii) a Behavioural Response variable as the observable feedback mechanism, which reflects land and water management decisions relevant to the hydrological context. The framework makes a further contribution through the introduction of three macro-scale parameters that enable it to normalise for differences in climate, socioeconomic and political gradients across study sites. In this way, the framework provides for both macro-scale contextual parameters, which allow for comparative studies to be undertaken, and catchment-specific conditions, by way of tailored "closure relationships", in order to ensure that site-specific and application-specific contexts of socio-hydrologic problems can be accommodated. To demonstrate how such a framework would be applied, two socio-hydrological case studies, taken from the Australian experience, are presented </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=computer&pg=7&id=EJ948642','ERIC'); return false;" href="https://eric.ed.gov/?q=computer&pg=7&id=EJ948642">Computer-Generated Feedback on Student Writing</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Ware, Paige 2011-01-01 A distinction must be made between "computer-generated scoring" and "computer-generated feedback". Computer-generated scoring refers to the provision of automated scores derived from mathematical models built on organizational, syntactic, and mechanical aspects of writing. In contrast, computer-generated feedback, the focus of this article, refers… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26621339','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26621339">Depression as a systemic syndrome: mapping the feedback loops of major depressive disorder.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Wittenborn, A K; Rahmandad, H; Rick, J; Hosseinichimeh, N 2016-02-01 Depression is a complex public health problem with considerable variation in treatment response. The systemic complexity of depression, or the feedback processes among diverse drivers of the disorder, contribute to the persistence of depression. This paper extends prior attempts to understand the complex causal feedback mechanisms that underlie depression by presenting the first broad boundary causal loop diagram of depression dynamics. We applied qualitative system dynamics methods to map the broad feedback mechanisms of depression. We used a structured approach to identify candidate causal mechanisms of depression in the literature. We assessed the strength of empirical support for each mechanism and prioritized those with support from validation studies. Through an iterative process, we synthesized the empirical literature and created a conceptual model of major depressive disorder. The literature review and synthesis resulted in the development of the first causal loop diagram of reinforcing feedback processes of depression. It proposes candidate drivers of illness, or inertial factors, and their temporal functioning, as well as the interactions among drivers of depression. The final causal loop diagram defines 13 key reinforcing feedback loops that involve nine candidate drivers of depression. Future research is needed to expand upon this initial model of depression dynamics. Quantitative extensions may result in a better understanding of the systemic syndrome of depression and contribute to personalized methods of evaluation, prevention and intervention. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4737091','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4737091">Depression as a systemic syndrome: mapping the feedback loops of major depressive disorder</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Wittenborn, A. K.; Rahmandad, H.; Rick, J.; Hosseinichimeh, N. 2016-01-01 Background Depression is a complex public health problem with considerable variation in treatment response. The systemic complexity of depression, or the feedback processes among diverse drivers of the disorder, contribute to the persistence of depression. This paper extends prior attempts to understand the complex causal feedback mechanisms that underlie depression by presenting the first broad boundary causal loop diagram of depression dynamics. Method We applied qualitative system dynamics methods to map the broad feedback mechanisms of depression. We used a structured approach to identify candidate causal mechanisms of depression in the literature. We assessed the strength of empirical support for each mechanism and prioritized those with support from validation studies. Through an iterative process, we synthesized the empirical literature and created a conceptual model of major depressive disorder. Results The literature review and synthesis resulted in the development of the first causal loop diagram of reinforcing feedback processes of depression. It proposes candidate drivers of illness, or inertial factors, and their temporal functioning, as well as the interactions among drivers of depression. The final causal loop diagram defines 13 key reinforcing feedback loops that involve nine candidate drivers of depression. Conclusions Future research is needed to expand upon this initial model of depression dynamics. Quantitative extensions may result in a better understanding of the systemic syndrome of depression and contribute to personalized methods of evaluation, prevention and intervention. PMID:26621339 </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018FNL....1750005V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018FNL....1750005V">Relation Between Firing Statistics of Spiking Neuron with Delayed Fast Inhibitory Feedback and Without Feedback</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Vidybida, Alexander; Shchur, Olha We consider a class of spiking neuronal models, defined by a set of conditions typical for basic threshold-type models, such as the leaky integrate-and-fire or the binding neuron model and also for some artificial neurons. A neuron is fed with a Poisson process. Each output impulse is applied to the neuron itself after a finite delay Δ. This impulse acts as being delivered through a fast Cl-type inhibitory synapse. We derive a general relation which allows calculating exactly the probability density function (pdf) p(t) of output interspike intervals of a neuron with feedback based on known pdf p0(t) for the same neuron without feedback and on the properties of the feedback line (the Δ value). Similar relations between corresponding moments are derived. Furthermore, we prove that the initial segment of pdf p0(t) for a neuron with a fixed threshold level is the same for any neuron satisfying the imposed conditions and is completely determined by the input stream. For the Poisson input stream, we calculate that initial segment exactly and, based on it, obtain exactly the initial segment of pdf p(t) for a neuron with feedback. That is the initial segment of p(t) is model-independent as well. The obtained expressions are checked by means of Monte Carlo simulation. The course of p(t) has a pronounced peculiarity, which makes it impossible to approximate p(t) by Poisson or another simple stochastic process. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19720024608','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19720024608">A feedback control model for network flow with multiple pure time delays</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Press, J. 1972-01-01 A control model describing a network flow hindered by multiple pure time (or transport) delays is formulated. Feedbacks connect each desired output with a single control sector situated at the origin. The dynamic formulation invokes the use of differential difference equations. This causes the characteristic equation of the model to consist of transcendental functions instead of a common algebraic polynomial. A general graphical criterion is developed to evaluate the stability of such a problem. A digital computer simulation confirms the validity of such criterion. An optimal decision making process with multiple delays is presented. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4550282','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4550282">Pluripotency, Differentiation, and Reprogramming: A Gene Expression Dynamics Model with Epigenetic Feedback Regulation</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Miyamoto, Tadashi; Furusawa, Chikara; Kaneko, Kunihiko 2015-01-01 Embryonic stem cells exhibit pluripotency: they can differentiate into all types of somatic cells. Pluripotent genes such as Oct4 and Nanog are activated in the pluripotent state, and their expression decreases during cell differentiation. Inversely, expression of differentiation genes such as Gata6 and Gata4 is promoted during differentiation. The gene regulatory network controlling the expression of these genes has been described, and slower-scale epigenetic modifications have been uncovered. Although the differentiation of pluripotent stem cells is normally irreversible, reprogramming of cells can be experimentally manipulated to regain pluripotency via overexpression of certain genes. Despite these experimental advances, the dynamics and mechanisms of differentiation and reprogramming are not yet fully understood. Based on recent experimental findings, we constructed a simple gene regulatory network including pluripotent and differentiation genes, and we demonstrated the existence of pluripotent and differentiated states from the resultant dynamical-systems model. Two differentiation mechanisms, interaction-induced switching from an expression oscillatory state and noise-assisted transition between bistable stationary states, were tested in the model. The former was found to be relevant to the differentiation process. We also introduced variables representing epigenetic modifications, which controlled the threshold for gene expression. By assuming positive feedback between expression levels and the epigenetic variables, we observed differentiation in expression dynamics. Additionally, with numerical reprogramming experiments for differentiated cells, we showed that pluripotency was recovered in cells by imposing overexpression of two pluripotent genes and external factors to control expression of differentiation genes. Interestingly, these factors were consistent with the four Yamanaka factors, Oct4, Sox2, Klf4, and Myc, which were necessary for the </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhDT........19I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhDT........19I">Model-based Optimization and Feedback Control of the Current Density Profile Evolution in NSTX-U</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Ilhan, Zeki Okan Nuclear fusion research is a highly challenging, multidisciplinary field seeking contributions from both plasma physics and multiple engineering areas. As an application of plasma control engineering, this dissertation mainly explores methods to control the current density profile evolution within the National Spherical Torus eXperiment-Upgrade (NSTX-U), which is a substantial upgrade based on the NSTX device, which is located in Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ. Active control of the toroidal current density profile is among those plasma control milestones that the NSTX-U program must achieve to realize its next-step operational goals, which are characterized by high-performance, long-pulse, MHD-stable plasma operation with neutral beam heating. Therefore, the aim of this work is to develop model-based, feedforward and feedback controllers that can enable time regulation of the current density profile in NSTX-U by actuating the total plasma current, electron density, and the powers of the individual neutral beam injectors. Motivated by the coupled, nonlinear, multivariable, distributed-parameter plasma dynamics, the first step towards control design is the development of a physics-based, control-oriented model for the current profile evolution in NSTX-U in response to non-inductive current drives and heating systems. Numerical simulations of the proposed control-oriented model show qualitative agreement with the high-fidelity physics code TRANSP. The next step is to utilize the proposed control-oriented model to design an open-loop actuator trajectory optimizer. Given a desired operating state, the optimizer produces the actuator trajectories that can steer the plasma to such state. The objective of the feedforward control design is to provide a more systematic approach to advanced scenario planning in NSTX-U since the development of such scenarios is conventionally carried out experimentally by modifying the tokamak's actuator </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=Formative+AND+assessment+AND+design+AND+instructional+AND+systems&pg=5&id=ED476707','ERIC'); return false;" href="https://eric.ed.gov/?q=Formative+AND+assessment+AND+design+AND+instructional+AND+systems&pg=5&id=ED476707">Using Hi-FAME (High Feedback-Assessment-Multimedia-Environment) Instructional Model in WBI: A Case Study for Biology Teacher Education.</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Wang, Tzu-Hua; Wang, Wei-Lung; Wang, Kuo-Hua; Huang, Shih-Chieh The study attempted to adapt two web tools, FFS system (Frontpage Feedback System) and WATA system (Web-based Assessment and Test Analysis System), to construct a Hi-FAME (High Feedback-Assessment-Multimedia-Environment) Model in WBI (Web-based Instruction) to facilitate pre-service teacher training. Participants were 30 junior pre-service… </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015IAUGA..2256792S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015IAUGA..2256792S">How to model AGN feedback in cosmological simulations?</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Sijacki, Debora 2015-08-01 Hydrodynamical cosmological simulations are one of the most powerful tools to study the formation and evolution of galaxies in the fully non-linear regime. Despite several recent successes in simulating Milky Way look-alikes, self-consistent, ab-initio models are still a long way off. In this talk I will review numerical and physical uncertainties plaguing current state-of-the-art cosmological simulations of galaxy formation. I will then discuss which feedback mechanisms are needed to reproduce realistic stellar masses and galaxy morphologies in the present day Universe and argue that the black hole feedback is necessary for the quenching of massive galaxies. I will then demonstrate how black hole - host galaxy scaling relations depend on galaxy morphology and colour, highlighting the implications for the co-evolutionary picture between galaxies and their central black holes. In the second part of the talk I will present a novel method that permits to resolve gas flows around black holes all the way from large cosmological scales to the Bondi radii of black holes themselves. I will demonstrate that with this new numerical technique it is possible to estimate much more accurately gas properties in the vicinity of black holes than has been feasible before in galaxy and cosmological simulations, allowing to track reliably gas angular momentum transport from Mpc to pc scales. Finally, I will also discuss if AGN-driven outflows are more likely to be energy- or momentum-driven and what implications this has for the redshift evolution of black hole - host galaxy scaling relations. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PlST...20b5404S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PlST...20b5404S">Feedback model of secondary electron emission in DC gas discharge plasmas</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Saravanan, ARUMUGAM; Prince, ALEX; Suraj, Kumar SINHA 2018-01-01 Feedback is said to exist in any amplifier when the fraction of output power in fed back as an input. Similarly, in gaseous discharge ions that incident on the cathode act as a natural feedback element to stabilize and self sustain the discharge. The present investigation is intended to emphasize the feedback nature of ions that emits secondary electrons (SEs) from the cathode surface in DC gas discharges. The average number of SEs emitted per incident ion and non ionic species (energetic neutrals, metastables and photons) which results from ion is defined as effective secondary electron emission coefficient (ESEEC,{γ }{{E}}). In this study, we derive an analytic expression that corroborates the relation between {γ }{{E}} and power influx by ion to the cathode based on the feedback theory of an amplifier. In addition, experimentally, we confirmed the typical positive feedback nature of SEE from the cathode in argon DC glow discharges. The experiment is done for three different cathode material of same dimension (tungsten (W), copper (Cu) and brass) under identical discharge conditions (pressure: 0.45 mbar, cathode bias: -600 V, discharge gab: 15 cm and operating gas: argon). Further, we found that the {γ }{{E}} value of these cathode material controls the amount of feedback power given by ions. The difference in feedback leads different final output i.e the power carried by ion at cathode ({P}{{i}}{\\prime }{| }{{C}}). The experimentally obtained value of {P}{{i}}{\\prime }{| }{{C}} is 4.28 W, 6.87 W and 9.26 W respectively for W, Cu and brass. In addition, the present investigation reveals that the amount of feedback power in a DC gas discharges not only affect the fraction of power fed back to the cathode but also the entire characteristics of the discharge. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.H41D0837M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.H41D0837M">Modeling Feedbacks Between Individual Human Decisions and Hydrology Using Interconnected Physical and Social Models</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Murphy, J.; Lammers, R. B.; Proussevitch, A. A.; Ozik, J.; Altaweel, M.; Collier, N. T.; Alessa, L.; Kliskey, A. D. 2014-12-01 The global hydrological cycle intersects with human decision making at multiple scales, from dams and irrigation works to the taps in individuals' homes. Residential water consumers are commonly encouraged to conserve; these messages are heard against a background of individual values and conceptions about water quality, uses, and availability. The degree to which these values impact the larger-hydrological dynamics, the way that changes in those values have impacts on the hydrological cycle through time, and the feedbacks by which water availability and quality in turn shape those values, are not well explored. To investigate this domain we employ a global-scale water balance model (WBM) coupled with a social-science-grounded agent-based model (ABM). The integration of a hydrological model with an agent-based model allows us to explore driving factors in the dynamics in coupled human-natural systems. From the perspective of the physical hydrologist, the ABM offers a richer means of incorporating the human decisions that drive the hydrological system; from the view of the social scientist, a physically-based hydrological model allows the decisions of the agents to play out against constraints faithful to the real world. We apply the interconnected models to a study of Tucson, Arizona, USA, and its role in the larger Colorado River system. Our core concept is Technology-Induced Environmental Distancing (TIED), which posits that layers of technology can insulate consumers from direct knowledge of a resource. In Tucson, multiple infrastructure and institutional layers have arguably increased the conceptual distance between individuals and their water supply, offering a test case of the TIED framework. Our coupled simulation allows us to show how the larger system transforms a resource with high temporal and spatial variability into a consumer constant, and the effects of this transformation on the regional system. We use this to explore how pricing, messaging, and </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.H13C1109S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.H13C1109S">Coupled MODEL Intercomparison Project PHASE 5 (CMIP5) Projected Twenty-First Century Warming over Southern Africa: Role of LOCAL Feedbacks</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Shongwe, M. 2014-12-01 The warming rates projected by an ensemble of the Coupled Model Intercomparion Project Phase 5 (CMIP5) global climate models (GCMs) over southern Africa (south of 10 degrees latitude) are investigated. In all RCPs, CMIP5 models project a higher warming rate over the southwestern parts centred around the arid Kalahari and Namib deserts. The higher warming rates over these areas outpace global warming by up to a factor 2 in some GCMs. The projected warming is associated with an increase in heat waves. There is notable consensus across the models with little intermodel spread, suggesting a strong robustness of the projections. Mechanisms underlying the enhanced warming are investigated. A positive soil moisture-temperature feedback is suggested to contribute to the accelerated temperature increase. A decrease in soil moisture is projected by the GCMs over the area of highest warming. The reduction in soil wetness reduces evapotranspiration rates over the area where evaporation is dependent on available soil moisture. The reduction is evapotranspiration affects the partitioning of turbulent energy fluxes from the soil surface into the atmosphere and translates into an increase of the Bowen ratio featuring an increase in sensible relative to latent heat flux. An increase in sensible heat flux leads to an increase in near-surface temperature. The increase in temperature leads to a higher vapour pressure deficit and evaporative demand and evapotranspiration from the dry soils, possibly leading to a further decrease in soil moisture. A precipitation-soil moisture feedback is also suggested. A decrease in mean precipitation and an increase in drought conditions are projected over the area of enhanced warming. The reduced precipitation results in drier soils. The drier soil translates to reduced evapotranspiration for cloud and rainfall formation. However, the role played by the soil moisture-precipitation feedback loop is still inconclusive and characterized by some degree </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21541321','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21541321">Collective irrationality and positive feedback.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Nicolis, Stamatios C; Zabzina, Natalia; Latty, Tanya; Sumpter, David J T 2011-04-26 Recent experiments on ants and slime moulds have assessed the degree to which they make rational decisions when presented with a number of alternative food sources or shelter. Ants and slime moulds are just two examples of a wide range of species and biological processes that use positive feedback mechanisms to reach decisions. Here we use a generic, experimentally validated model of positive feedback between group members to show that the probability of taking the best of options depends crucially on the strength of feedback. We show how the probability of choosing the best option can be maximized by applying an optimal feedback strength. Importantly, this optimal value depends on the number of options, so that when we change the number of options the preference of the group changes, producing apparent "irrationalities". We thus reinterpret the idea that collectives show "rational" or "irrational" preferences as being a necessary consequence of the use of positive feedback. We argue that positive feedback is a heuristic which often produces fast and accurate group decision-making, but is always susceptible to apparent irrationality when studied under particular experimental conditions. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2701448','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2701448">Haptic Feedback in Robot-Assisted Minimally Invasive Surgery</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Okamura, Allison M. 2009-01-01 Purpose of Review Robot-assisted minimally invasive surgery (RMIS) holds great promise for improving the accuracy and dexterity of a surgeon while minimizing trauma to the patient. However, widespread clinical success with RMIS has been marginal. It is hypothesized that the lack of haptic (force and tactile) feedback presented to the surgeon is a limiting factor. This review explains the technical challenges of creating haptic feedback for robot-assisted surgery and provides recent results that evaluate the effectiveness of haptic feedback in mock surgical tasks. Recent Findings Haptic feedback systems for RMIS are still under development and evaluation. Most provide only force feedback, with limited fidelity. The major challenge at this time is sensing forces applied to the patient. A few tactile feedback systems for RMIS have been created, but their practicality for clinical implementation needs to be shown. It is particularly difficult to sense and display spatially distributed tactile information. The cost-benefit ratio for haptic feedback in RMIS has not been established. Summary The designs of existing commercial RMIS systems are not conducive for force feedback, and creative solutions are needed to create compelling tactile feedback systems. Surgeons, engineers, and neuroscientists should work together to develop effective solutions for haptic feedback in RMIS. PMID:19057225 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5805346','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5805346">Biophysical network modeling of the dLGN circuit: Effects of cortical feedback on spatial response properties of relay cells</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Martínez-Cañada, Pablo; Halnes, Geir; Fyhn, Marianne 2018-01-01 Despite half-a-century of research since the seminal work of Hubel and Wiesel, the role of the dorsal lateral geniculate nucleus (dLGN) in shaping the visual signals is not properly understood. Placed on route from retina to primary visual cortex in the early visual pathway, a striking feature of the dLGN circuit is that both the relay cells (RCs) and interneurons (INs) not only receive feedforward input from retinal ganglion cells, but also a prominent feedback from cells in layer 6 of visual cortex. This feedback has been proposed to affect synchronicity and other temporal properties of the RC firing. It has also been seen to affect spatial properties such as the center-surround antagonism of thalamic receptive fields, i.e., the suppression of the response to very large stimuli compared to smaller, more optimal stimuli. Here we explore the spatial effects of cortical feedback on the RC response by means of a a comprehensive network model with biophysically detailed, single-compartment and multicompartment neuron models of RCs, INs and a population of orientation-selective layer 6 simple cells, consisting of pyramidal cells (PY). We have considered two different arrangements of synaptic feedback from the ON and OFF zones in the visual cortex to the dLGN: phase-reversed (‘push-pull’) and phase-matched (‘push-push’), as well as different spatial extents of the corticothalamic projection pattern. Our simulation results support that a phase-reversed arrangement provides a more effective way for cortical feedback to provide the increased center-surround antagonism seen in experiments both for flashing spots and, even more prominently, for patch gratings. This implies that ON-center RCs receive direct excitation from OFF-dominated cortical cells and indirect inhibitory feedback from ON-dominated cortical cells. The increased center-surround antagonism in the model is accompanied by spatial focusing, i.e., the maximum RC response occurs for smaller stimuli when </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27606244','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27606244">Using Video Modeling with Voiceover Instruction Plus Feedback to Train Staff to Implement Direct Teaching Procedures.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Giannakakos, Antonia R; Vladescu, Jason C; Kisamore, April N; Reeve, Sharon A 2016-06-01 Direct teaching procedures are often an important part of early intensive behavioral intervention for consumers with autism spectrum disorder. In the present study, a video model with voiceover (VMVO) instruction plus feedback was evaluated to train three staff trainees to implement a most-to-least direct (MTL) teaching procedure. Probes for generalization were conducted with untrained direct teaching procedures (i.e., least-to-most, prompt delay) and with an actual consumer. The results indicated that VMVO plus feedback was effective in training the staff trainees to implement the MTL procedure. Although additional feedback was required for the staff trainees to show mastery of the untrained direct teaching procedures (i.e., least-to-most and prompt delay) and with an actual consumer, moderate to high levels of generalization were observed. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ESD.....8..357N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ESD.....8..357N">A model study of warming-induced phosphorus-oxygen feedbacks in open-ocean oxygen minimum zones on millennial timescales</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Niemeyer, Daniela; Kemena, Tronje P.; Meissner, Katrin J.; Oschlies, Andreas 2017-05-01 Observations indicate an expansion of oxygen minimum zones (OMZs) over the past 50 years, likely related to ongoing deoxygenation caused by reduced oxygen solubility, changes in stratification and circulation, and a potential acceleration of organic matter turnover in a warming climate. The overall area of ocean sediments that are in direct contact with low-oxygen bottom waters also increases with expanding OMZs. This leads to a release of phosphorus from ocean sediments. If anthropogenic carbon dioxide emissions continue unabated, higher temperatures will cause enhanced weathering on land, which, in turn, will increase the phosphorus and alkalinity fluxes into the ocean and therefore raise the ocean's phosphorus inventory even further. A higher availability of phosphorus enhances biological production, remineralisation and oxygen consumption, and might therefore lead to further expansions of OMZs, representing a positive feedback. A negative feedback arises from the enhanced productivity-induced drawdown of carbon and also increased uptake of CO2 due to weathering-induced alkalinity input. This feedback leads to a decrease in atmospheric CO2 and weathering rates. Here, we quantify these two competing feedbacks on millennial timescales for a high CO2 emission scenario. Using the University of Victoria (UVic) Earth System Climate Model of intermediate complexity, our model results suggest that the positive benthic phosphorus release feedback has only a minor impact on the size of OMZs in the next 1000 years. The increase in the marine phosphorus inventory under assumed business-as-usual global warming conditions originates, on millennial timescales, almost exclusively (> 80 %) from the input via terrestrial weathering and causes a 4- to 5-fold expansion of the suboxic water volume in the model. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5124963','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5124963">Negative feedback regulation of ABA biosynthesis in peanut (Arachis hypogaea): a transcription factor complex inhibits AhNCED1 expression during water stress</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Liu, Shuai; Li, Meijuan; Su, Liangchen; Ge, Kui; Li, Limei; Li, Xiaoyun; Liu, Xu; Li, Ling 2016-01-01 Abscisic acid (ABA), a key plant stress-signaling hormone, is produced in response to drought and counteracts the effects of this stress. The accumulation of ABA is controlled by the enzyme 9-cis-epoxycarotenoid dioxygenase (NCED). In Arabidopsis, NCED3 is regulated by a positive feedback mechanism by ABA. In this study in peanut (Arachis hypogaea), we demonstrate that ABA biosynthesis is also controlled by negative feedback regulation, mediated by the inhibitory effect on AhNCED1 transcription of a protein complex between transcription factors AhNAC2 and AhAREB1. AhNCED1 was significantly down-regulated after PEG treatment for 10 h, at which time ABA content reached a peak. A ChIP-qPCR assay confirmed AhAREB1 and AhNAC2 binding to the AhNCED1 promoter in response to ABA. Moreover, the interaction between AhAREB1 and AhNAC2, and a transient expression assay showed that the protein complex could negatively regulate the expression of AhNCED1. The results also demonstrated that AhAREB1 was the key factor in AhNCED1 feedback regulation, while AhNAC2 played a subsidiary role. ABA reduced the rate of AhAREB1 degradation and enhanced both the synthesis and degradation rate of the AhNAC2 protein. In summary, the AhAREB1/AhNAC2 protein complex functions as a negative feedback regulator of drought-induced ABA biosynthesis in peanut. PMID:27892506 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24989869','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24989869">How we give personalised audio feedback after summative OSCEs.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Harrison, Christopher J; Molyneux, Adrian J; Blackwell, Sara; Wass, Valerie J 2015-04-01 Students often receive little feedback after summative objective structured clinical examinations (OSCEs) to enable them to improve their performance. Electronic audio feedback has shown promise in other educational areas. We investigated the feasibility of electronic audio feedback in OSCEs. An electronic OSCE system was designed, comprising (1) an application for iPads allowing examiners to mark in the key consultation skill domains, provide "tick-box" feedback identifying strengths and difficulties, and record voice feedback; (2) a feedback website giving students the opportunity to view/listen in multiple ways to the feedback. Acceptability of the audio feedback was investigated, using focus groups with students and questionnaires with both examiners and students. 87 (95%) students accessed the examiners' audio comments; 83 (90%) found the comments useful and 63 (68%) reported changing the way they perform a skill as a result of the audio feedback. They valued its highly personalised, relevant nature and found it much more useful than written feedback. Eighty-nine per cent of examiners gave audio feedback to all students on their stations. Although many found the method easy, lack of time was a factor. Electronic audio feedback provides timely, personalised feedback to students after a summative OSCE provided enough time is allocated to the process. </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active">14</li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active">15</li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19964205','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19964205">Real-time implementation of biofidelic SA1 model for tactile feedback.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Russell, A F; Armiger, R S; Vogelstein, R J; Bensmaia, S J; Etienne-Cummings, R 2009-01-01 In order for the functionality of an upper-limb prosthesis to approach that of a real limb it must be able to, accurately and intuitively, convey sensory feedback to the limb user. This paper presents results of the real-time implementation of a 'biofidelic' model that describes mechanotransduction in Slowly Adapting Type 1 (SA1) afferent fibers. The model accurately predicts the timing of action potentials for arbitrary force or displacement stimuli and its output can be used as stimulation times for peripheral nerve stimulation by a neuroprosthetic device. The model performance was verified by comparing the predicted action potential (or spike) outputs against measured spike outputs for different vibratory stimuli. Furthermore experiments were conducted to show that, like real SA1 fibers, the model's spike rate varies according to input pressure and that a periodic 'tapping' stimulus evokes periodic spike outputs. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28741446','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28741446">Uncovering the unknown: A grounded theory study exploring the impact of self-awareness on the culture of feedback in residency education.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Ramani, Subha; Könings, Karen; Mann, Karen V; van der Vleuten, Cees 2017-10-01 Self-assessment and reflection are essential for meaningful feedback. We aimed to explore whether the well-known Johari window model of self-awareness could guide feedback conversations between faculty and residents and enhance the institutional feedback culture. We had previously explored perceptions of residents and faculty regarding sociocultural factors impacting feedback. We re-analyzed data targeting themes related to self-assessment, reflection, feedback seeking and acceptance, aiming to generate individual and institutional feedback strategies applicable to each quadrant of the window. We identified the following themes for each quadrant: (1) Behaviors known to self and others - Validating the known; (2) Behaviors unknown to self but known to others - Accepting the blind; (3) Behaviors known to self and unknown to others - Disclosure of hidden; and (4) Behaviors unknown to self and others - Uncovering the unknown. Normalizing self-disclosure of limitations, encouraging feedback seeking, training in nonjudgmental feedback and providing opportunities for longitudinal relationships could promote self-awareness, ultimately expanding the "open" quadrant of the Johari window. The Johari window, a model of self-awareness in interpersonal communications, could provide a robust framework for individuals to improve their feedback conversations and institutions to design feedback initiatives that enhance its quality and impact. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23135749','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23135749">Probability matching in risky choice: the interplay of feedback and strategy availability.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Newell, Ben R; Koehler, Derek J; James, Greta; Rakow, Tim; van Ravenzwaaij, Don 2013-04-01 Probability matching in sequential decision making is a striking violation of rational choice that has been observed in hundreds of experiments. Recent studies have demonstrated that matching persists even in described tasks in which all the information required for identifying a superior alternative strategy-maximizing-is present before the first choice is made. These studies have also indicated that maximizing increases when (1) the asymmetry in the availability of matching and maximizing strategies is reduced and (2) normatively irrelevant outcome feedback is provided. In the two experiments reported here, we examined the joint influences of these factors, revealing that strategy availability and outcome feedback operate on different time courses. Both behavioral and modeling results showed that while availability of the maximizing strategy increases the choice of maximizing early during the task, feedback appears to act more slowly to erode misconceptions about the task and to reinforce optimal responding. The results illuminate the interplay between "top-down" identification of choice strategies and "bottom-up" discovery of those strategies via feedback. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=Audio&id=EJ1032053','ERIC'); return false;" href="https://eric.ed.gov/?q=Audio&id=EJ1032053">Audio Feedback -- Better Feedback?</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Voelkel, Susanne; Mello, Luciane V. 2014-01-01 National Student Survey (NSS) results show that many students are dissatisfied with the amount and quality of feedback they get for their work. This study reports on two case studies in which we tried to address these issues by introducing audio feedback to one undergraduate (UG) and one postgraduate (PG) class, respectively. In case study one… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1362194','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/1362194">Biospheric feedback effects in a synchronously coupled model of human and Earth systems</a> <a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a> Thornton, Peter E.; Calvin, Katherine; Jones, Andrew D. Fossil fuel combustion and land-use change are the two largest contributors to industrial-era increases in atmospheric CO 2 concentration. Projections of these are thus fundamental inputs for coupled Earth system models (ESMs) used to estimate the physical and biological consequences of future climate system forcing. While historical datasets are available to inform past and current climate analyses, assessments of future climate change have relied on projections of energy and land use from energy economic models, constrained by assumptions about future policy, land-use patterns, and socio-economic development trajectories. We show that the climatic impacts on land ecosystems drives significant feedbacks inmore » energy, agriculture, land-use, and carbon cycle projections for the 21st century. We also find that exposure of human appropriated land ecosystem productivity to biospheric change results in reductions of land area used for crops; increases in managed forest area and carbon stocks; decreases in global crop prices; and reduction in fossil fuel emissions for a low-mid range forcing scenario. Furthermore, the feedbacks between climate-induced biospheric change and human system forcings to the climate system demonstrated here are handled inconsistently, or excluded altogether, in the one-way asynchronous coupling of energy economic models to ESMs used to date.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017NatCC...7..496T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017NatCC...7..496T">Biospheric feedback effects in a synchronously coupled model of human and Earth systems</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Thornton, Peter E.; Calvin, Katherine; Jones, Andrew D.; di Vittorio, Alan V.; Bond-Lamberty, Ben; Chini, Louise; Shi, Xiaoying; Mao, Jiafu; Collins, William D.; Edmonds, Jae; Thomson, Allison; Truesdale, John; Craig, Anthony; Branstetter, Marcia L.; Hurtt, George 2017-07-01 Fossil fuel combustion and land-use change are the two largest contributors to industrial-era increases in atmospheric CO 2 concentration. Projections of these are thus fundamental inputs for coupled Earth system models (ESMs) used to estimate the physical and biological consequences of future climate system forcing. While historical data sets are available to inform past and current climate analyses, assessments of future climate change have relied on projections of energy and land use from energy-economic models, constrained by assumptions about future policy, land-use patterns and socio-economic development trajectories. Here we show that the climatic impacts on land ecosystems drive significant feedbacks in energy, agriculture, land use and carbon cycle projections for the twenty-first century. We find that exposure of human-appropriated land ecosystem productivity to biospheric change results in reductions of land area used for crops; increases in managed forest area and carbon stocks; decreases in global crop prices; and reduction in fossil fuel emissions for a low-mid-range forcing scenario. The feedbacks between climate-induced biospheric change and human system forcings to the climate system--demonstrated here--are handled inconsistently, or excluded altogether, in the one-way asynchronous coupling of energy-economic models to ESMs used to date. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1362194-biospheric-feedback-effects-synchronously-coupled-model-human-earth-systems','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1362194-biospheric-feedback-effects-synchronously-coupled-model-human-earth-systems">Biospheric feedback effects in a synchronously coupled model of human and Earth systems</a> <a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a> Thornton, Peter E.; Calvin, Katherine; Jones, Andrew D.; ... 2017-06-12 Fossil fuel combustion and land-use change are the two largest contributors to industrial-era increases in atmospheric CO 2 concentration. Projections of these are thus fundamental inputs for coupled Earth system models (ESMs) used to estimate the physical and biological consequences of future climate system forcing. While historical datasets are available to inform past and current climate analyses, assessments of future climate change have relied on projections of energy and land use from energy economic models, constrained by assumptions about future policy, land-use patterns, and socio-economic development trajectories. We show that the climatic impacts on land ecosystems drives significant feedbacks inmore » energy, agriculture, land-use, and carbon cycle projections for the 21st century. We also find that exposure of human appropriated land ecosystem productivity to biospheric change results in reductions of land area used for crops; increases in managed forest area and carbon stocks; decreases in global crop prices; and reduction in fossil fuel emissions for a low-mid range forcing scenario. Furthermore, the feedbacks between climate-induced biospheric change and human system forcings to the climate system demonstrated here are handled inconsistently, or excluded altogether, in the one-way asynchronous coupling of energy economic models to ESMs used to date.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhRvE..95a2201B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhRvE..95a2201B">Self-tuning bistable parametric feedback oscillator: Near-optimal amplitude maximization without model information</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Braun, David J.; Sutas, Andrius; Vijayakumar, Sethu 2017-01-01 Theory predicts that parametrically excited oscillators, tuned to operate under resonant condition, are capable of large-amplitude oscillation useful in diverse applications, such as signal amplification, communication, and analog computation. However, due to amplitude saturation caused by nonlinearity, lack of robustness to model uncertainty, and limited sensitivity to parameter modulation, these oscillators require fine-tuning and strong modulation to generate robust large-amplitude oscillation. Here we present a principle of self-tuning parametric feedback excitation that alleviates the above-mentioned limitations. This is achieved using a minimalistic control implementation that performs (i) self-tuning (slow parameter adaptation) and (ii) feedback pumping (fast parameter modulation), without sophisticated signal processing past observations. The proposed approach provides near-optimal amplitude maximization without requiring model-based control computation, previously perceived inevitable to implement optimal control principles in practical application. Experimental implementation of the theory shows that the oscillator self-tunes itself near to the onset of dynamic bifurcation to achieve extreme sensitivity to small resonant parametric perturbations. As a result, it achieves large-amplitude oscillations by capitalizing on the effect of nonlinearity, despite substantial model uncertainties and strong unforeseen external perturbations. We envision the present finding to provide an effective and robust approach to parametric excitation when it comes to real-world application. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1238757','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1238757">Effectiveness and cost of different strategies for information feedback in general practice.</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Szczepura, A; Wilmot, J; Davies, C; Fletcher, J 1994-01-01 AIM. The aim of this study was to determine the effectiveness and relative cost of three forms of information feedback to general practices--graphical, graphical plus a visit by a medical facilitator and tabular. METHOD. Routinely collected, centrally-held data were used where possible, analysed at practice level. Some non-routine practice data in the form of risk factor recording in medical notes, for example weight, smoking status, alcohol consumption and blood pressure, were also provided to those who requested it. The 52 participating practices were stratified and randomly allocated to one of the three feedback groups. The cost of providing each type of feedback was determined. The immediate response of practitioners to the form of feedback (acceptability), ease of understanding (intelligibility), and usefulness of regular feedback was recorded. Changes introduced as a result of feedback were assessed by questionnaire shortly after feedback, and 12 months later. Changes at the practice level in selected indicators were also assessed 12 and 24 months after initial feedback. RESULTS. The resulting cost per effect was calculated to be 46.10 pounds for both graphical and tabular feedback, 132.50 pounds for graphical feedback plus facilitator visit and 773.00 pounds for the manual audit of risk factors recorded in the practice notes. The three forms of feedback did not differ in intelligibility or usefulness, but feedback plus a medical facilitator visit was significantly less acceptable. There was a high level of self-reported organizational change following feedback, with 69% of practices reporting changes as a direct result; this was not significantly different for the three types of feedback. There were no significant changes in the selected indicators at 12 or 24 months following feedback. The practice characteristic most closely related to better indicators of preventive practice was practice size, smaller practices performing significantly better. Separate </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005JCli...18..237S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005JCli...18..237S">Cloud Feedbacks in the Climate System: A Critical Review.</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Stephens, Graeme L. 2005-01-01 This paper offers a critical review of the topic of cloud-climate feedbacks and exposes some of the underlying reasons for the inherent lack of understanding of these feedbacks and why progress might be expected on this important climate problem in the coming decade. Although many processes and related parameters come under the influence of clouds, it is argued that atmospheric processes fundamentally govern the cloud feedbacks via the relationship between the atmospheric circulations, cloudiness, and the radiative and latent heating of the atmosphere. It is also shown how perturbations to the atmospheric radiation budget that are induced by cloud changes in response to climate forcing dictate the eventual response of the global-mean hydrological cycle of the climate model to climate forcing. This suggests that cloud feedbacks are likely to control the bulk precipitation efficiency and associated responses of the planet's hydrological cycle to climate radiative forcings.The paper provides a brief overview of the effects of clouds on the radiation budget of the earth-atmosphere system and a review of cloud feedbacks as they have been defined in simple systems, one being a system in radiative-convective equilibrium (RCE) and others relating to simple feedback ideas that regulate tropical SSTs. The systems perspective is reviewed as it has served as the basis for most feedback analyses. What emerges is the importance of being clear about the definition of the system. It is shown how different assumptions about the system produce very different conclusions about the magnitude and sign of feedbacks. Much more diligence is called for in terms of defining the system and justifying assumptions. In principle, there is also neither any theoretical basis to justify the system that defines feedbacks in terms of global-time-mean changes in surface temperature nor is there any compelling empirical evidence to do so. The lack of maturity of feedback analysis methods also suggests </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20225784','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20225784">Understanding constructive feedback: a commitment between teachers and students for academic and professional development.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Hamid, Yasir; Mahmood, Sajid 2010-03-01 This review highlights the need in the Pakistani medical education system for teachers and students to be able to: define constructive feedback; provide constructive feedback; identify standards for constructive feedback; identify a suitable model for the provision of constructive feedback and evaluate the use of constructive feedback. For the purpose of literature review we had defined the key word glossary as: feedback, constructive feedback, teaching constructive feedback, models for feedback, models for constructive feedback and giving and receiving feedback. The data bases for the search include: Medline (EBSCO), Web of Knowledge, SCOPUS, TRIP, ScienceDirect, Pubmed, U.K. Pubmed Central, ZETOC, University of Dundee Library catalogue, SCIRUS (Elsevier) and Google Scholar. This article states that the Pakistani medical schools do not reflect on or use the benefits of the constructive feedback process. The discussion about constructive feedback suggests that in the context of Pakistan, constructive feedback will facilitate the teaching and learning activities. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.B43F0354R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.B43F0354R">Dynamic Mesoscale Land-Atmosphere Feedbacks in Fragmented Forests in Amazonia</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Rastogi, D.; Baidya Roy, S. 2011-12-01 This paper investigates land-atmosphere feedbacks in disturbed rainforests of Amazonia. Deforestation along the rapidly expanding highways and road network has created the unique fishbone land cover pattern in Rondonia, a state in southwestern Amazonia. Numerical experiments and observations show that sharp gradients in land cover due to the fishbone heterogeneity triggers mesoscale circulations. These circulations significantly change the spatial pattern of local hydrometeorology, especially convection, clouds and precipitation. The primary research question now is can these changes in local hydrometeorology affect vegetation growth in the clearings. If so, that would be a clear indication that land-atmosphere feedbacks can affect vegetation recovery in fragmented forests. A computationally-efficient modeling tool consisting of a mesoscale atmospheric model dynamically coupled with a plant growth model has been specifically developed to identify the atmospheric feedback pathways. Preliminary experiments focus on the seasonal-scale feedbacks during the dry season. Results show that temperature, incoming shortwave and precipitation are the three primary drivers through which the feedbacks operate. Increasing temperature increases respiratory losses generating a positive feedback. Increased cloud cover reduces incoming PAR and photosynthesis, resulting in a positive feedback. Increased precipitation reduces water stress and promotes growth resulting in a negative feedback. The net effect is a combination of these 3 feedback loops. These findings can significantly improve our understanding of ecosystem resiliency in disturbed tropical forests. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=industrial+AND+design&id=EJ1155032','ERIC'); return false;" href="https://eric.ed.gov/?q=industrial+AND+design&id=EJ1155032">Feedback Conversations: Creating Feedback Dialogues with a New Textual Tool for Industrial Design Student Feedback</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Funk, Mathias; van Diggelen, Migchiel 2017-01-01 In this paper, the authors describe how a study of a large database of written university teacher feedback in the department of Industrial Design led to the development of a new conceptual framework for feedback and the design of a new feedback tool. This paper focuses on the translation of related work in the area of feedback mechanisms for… </li> <li> <a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840021834','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840021834">Approximation techniques for parameter estimation and feedback control for distributed models of large flexible structures</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Banks, H. T.; Rosen, I. G. 1984-01-01 Approximation ideas are discussed that can be used in parameter estimation and feedback control for Euler-Bernoulli models of elastic systems. Focusing on parameter estimation problems, ways by which one can obtain convergence results for cubic spline based schemes for hybrid models involving an elastic cantilevered beam with tip mass and base acceleration are outlined. Sample numerical findings are also presented. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.A33R..01W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.A33R..01W">Vegetation-climate feedback causes reduced precipitation and tropical rainforest cover in CMIP5 regional Earth system model simulation over Africa</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Wu, M.; Smith, B.; Samuelsson, P.; Rummukainen, M.; Schurgers, G. 2012-12-01 We applied a coupled regional climate-vegetation model, RCA-GUESS (Smith et al. 2011), over the CORDEX Africa domain, forced by boundary conditions from a CanESM2 CMIP5 simulation under the RCP8.5 future climate scenario. The simulations were from 1961 to 2100 and covered the African continent at a horizontal grid spacing of 0.44°. RCA-GUESS simulates changes in the phenology, productivity, relative cover and population structure of up to eight plant function types (PFTs) in response to forcing from the climate part of the model. These vegetation changes feed back to simulated climate through dynamic adjustments in surface energy fluxes and surface properties. Changes in the net ecosystem-atmosphere carbon flux and its components net primary production (NPP), heterotrophic respiration and emissions from biomass burning were also simulated but do not feed back to climate in our model. Constant land cover was assumed. We compared simulations with and without vegetation feedback switched "on" to assess the influence of vegetation-climate feedback on simulated climate, vegetation and ecosystem carbon cycling. Both positive and negative warming feedbacks were identified in different parts of Africa. In the Sahel savannah zone near 15°N, reduced vegetation cover and productivity, and mortality caused by a deterioration of soil water conditions led to a positive warming feedback mediated by decreased evapotranspiration and increased sensible heat flux between vegetation and the atmosphere. In the equatorial rainforest stronghold region of central Africa, a feedback syndrome characterised by reduced plant production and LAI, a dominance shift from tropical trees to grasses, reduced soil water and reduced rainfall was identified. The likely underlying mechanism was a decline in evaporative water recycling associated with sparser vegetation cover, reminiscent of Earth system model studies in which a similar feedback mechanism was simulated to force dieback of tropical </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2790943','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2790943">VIDEO MODELING BY EXPERTS WITH VIDEO FEEDBACK TO ENHANCE GYMNASTICS SKILLS</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Boyer, Eva; Miltenberger, Raymond G; Batsche, Catherine; Fogel, Victoria 2009-01-01 The effects of combining video modeling by experts with video feedback were analyzed with 4 female competitive gymnasts (7 to 10 years old) in a multiple baseline design across behaviors. During the intervention, after the gymnast performed a specific gymnastics skill, she viewed a video segment showing an expert gymnast performing the same skill and then viewed a video replay of her own performance of the skill. The results showed that all gymnasts demonstrated improved performance across three gymnastics skills following exposure to the intervention. PMID:20514194 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20514194','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20514194">Video modeling by experts with video feedback to enhance gymnastics skills.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Boyer, Eva; Miltenberger, Raymond G; Batsche, Catherine; Fogel, Victoria 2009-01-01 The effects of combining video modeling by experts with video feedback were analyzed with 4 female competitive gymnasts (7 to 10 years old) in a multiple baseline design across behaviors. During the intervention, after the gymnast performed a specific gymnastics skill, she viewed a video segment showing an expert gymnast performing the same skill and then viewed a video replay of her own performance of the skill. The results showed that all gymnasts demonstrated improved performance across three gymnastics skills following exposure to the intervention. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=attention+AND+size&pg=2&id=EJ1147927','ERIC'); return false;" href="https://eric.ed.gov/?q=attention+AND+size&pg=2&id=EJ1147927">Lessons from Alternative Grading: Essential Qualities of Teacher Feedback</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Percell, Jay C. 2017-01-01 One critically important step in the instructional process is providing feedback to students, and yet, providing timely and thorough feedback is often lacking due attention. Reasons for this oversight could range from several factors including increased class sizes, vast content coverage requirements, extracurricular responsibilities, and the… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22913632','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22913632">Modeling the optimal central carbon metabolic pathways under feedback inhibition using flux balance analysis.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> De, Rajat K; Tomar, Namrata 2012-12-01 Metabolism is a complex process for energy production for cellular activity. It consists of a cascade of reactions that form a highly branched network in which the product of one reaction is the reactant of the next reaction. Metabolic pathways efficiently produce maximal amount of biomass while maintaining a steady-state behavior. The steady-state activity of such biochemical pathways necessarily incorporates feedback inhibition of the enzymes. This observation motivates us to incorporate feedback inhibition for modeling the optimal activity of metabolic pathways using flux balance analysis (FBA). We demonstrate the effectiveness of the methodology on a synthetic pathway with and without feedback inhibition. Similarly, for the first time, the Central Carbon Metabolic (CCM) pathways of Saccharomyces cerevisiae and Homo sapiens have been modeled and compared based on the above understanding. The optimal pathway, which maximizes the amount of the target product(s), is selected from all those obtained by the proposed method. For this, we have observed the concentration of the product inhibited enzymes of CCM pathway and its influence on its corresponding metabolite/substrate. We have also studied the concentration of the enzymes which are responsible for the synthesis of target products. We further hypothesize that an optimal pathway would opt for higher flux rate reactions. In light of these observations, we can say that an optimal pathway should have lower enzyme concentration and higher flux rates. Finally, we demonstrate the superiority of the proposed method by comparing it with the extreme pathway analysis. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5768857','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5768857">Micro-Feedback Training:Learning the art of effective feedback</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Baseer, Najma; Mahboob, Usman; Degnan, James 2017-01-01 Multiple attributes are expected of postgraduate research supervisors. Provision of timely and effective face-to-face feedback is one such skill that carries enormous significance in supervisee’s professional development. Feedback allows the supervisees to improve upon their performances. Unfortunately, both supervisors and supervisees have contrasting approaches towards the ongoing feedback practices. This incongruence is attributed, in part, to a lack of structured pedagogic training among the medical professionals. A standardized schema is therefore required to acquire and harmonize this pedagogical skill. One such systemized way is a training method called microteaching. Microteaching has long been used to enhance and incorporate old and new undergraduate teaching skills, respectively. Here we propose a similar structured approach of micro-feedback to inculcate effective feedback skills among postgraduate research supervisors using feedback-based scenarios, simulated students, standardized checklists and audiovisual aids. Thus, micro-feedback exercise may prove to be quite promising in improving feedback practices of postgraduate research supervisors. PMID:29492091 </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active">15</li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active">16</li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25435591','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25435591">Coexistence and relative abundance in plant communities are determined by feedbacks when the scale of feedback and dispersal is local.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Mack, Keenan M L; Bever, James D 2014-09-01 1. Negative plant-soil feedback occurs when the presence of an individual of a particular species at a particular site decreases the relative success of individuals of the same species compared to those other species at that site. This effect favors heterospecifics thereby facilitating coexistence and maintaining diversity. Empirical work has demonstrated that the average strengths of these feedbacks correlate with the relative abundance of species within a community, suggesting that feedbacks are an important driver of plant community composition. Understanding what factors contribute to the generation of this relationship is necessary for diagnosing the dynamic forces that maintain diversity in plant communities. 2. We used a spatially explicit, individual-based computer simulation to test the effects of dispersal distance, the size of feedback neighbourhoods, the strength of pairwise feedbacks and community wide variation of feedbacks, community richness, as well as life-history differences on the dependence of relative abundance on strength of feedback. 3. We found a positive dependence of relative abundance of a species on its average feedback for local scale dispersal and feedback. However, we found that the strength of this dependence decreased as either the spatial scale of dispersal and/or the spatial scale of feedback increased. We also found that for spatially local (i.e. relatively small) scale interaction and dispersal, as the mean strength of feedbacks in the community becomes less negative, the greater the increase in abundance produced by a comparable increase in species-specific average feedback. We found that life-history differences such as mortality rate did not generate a pattern with abundance, nor did they affect the relationship between abundance and average feedback. 4. Synthesis . Our results support the claim that empirical observations of a positive correlation between relative abundance and strength of average feedback serves as </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.H11L..06T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.H11L..06T">Soil moisture - precipitation feedbacks in observations and models (Invited)</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Taylor, C. 2013-12-01 There is considerable uncertainty about the strength, geographical extent, and even the sign of feedbacks between soil moisture and precipitation. Whilst precipitation trivially increases soil moisture, the impact of soil moisture, via surface fluxes, on convective rainfall is far from straight-forward, and likely depends on space and time scale, soil and synoptic conditions, and the nature of the convection itself. In considering how daytime convection responds to surface fluxes, large-scale models based on convective parameterisations may not necessarily provide reliable depictions, particularly given their long-standing inability to reproduce a realistic diurnal cycle of convection. On the other hand, long-term satellite data provide the potential to establish robust relationships between soil moisture and precipitation across the world, notwithstanding some fundamental weaknesses and uncertainties in the datasets. Here, results from regional and global satellite-based analyses are presented. Globally, using 3-hourly precipitation and daily soil moisture datasets, a methodology has been developed to compare the statistics of antecedent soil moisture in the region of localised afternoon rain events (Taylor et al 2012). Specifically the analysis tests whether there are any significant differences in pre-event soil moisture between rainfall maxima and nearby (50-100km) minima. The results reveal a clear signal across a number of semi-arid regions, most notably North Africa, indicating a preference for afternoon rain over drier soil. Analysis by continent and by climatic zone reveals that this signal (locally a negative feedback) is evident in other continents and climatic zones, but is somewhat weaker. This may be linked to the inherent geographical differences across the world, as detection of a feedback requires water-stressed surfaces coincident with frequent active convective initiations. The differences also reflect the quality and utility of the soil moisture </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3658624','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3658624">Neural mechanisms underlying auditory feedback control of speech</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Reilly, Kevin J.; Guenther, Frank H. 2013-01-01 The neural substrates underlying auditory feedback control of speech were investigated using a combination of functional magnetic resonance imaging (fMRI) and computational modeling. Neural responses were measured while subjects spoke monosyllabic words under two conditions: (i) normal auditory feedback of their speech, and (ii) auditory feedback in which the first formant frequency of their speech was unexpectedly shifted in real time. Acoustic measurements showed compensation to the shift within approximately 135 ms of onset. Neuroimaging revealed increased activity in bilateral superior temporal cortex during shifted feedback, indicative of neurons coding mismatches between expected and actual auditory signals, as well as right prefrontal and Rolandic cortical activity. Structural equation modeling revealed increased influence of bilateral auditory cortical areas on right frontal areas during shifted speech, indicating that projections from auditory error cells in posterior superior temporal cortex to motor correction cells in right frontal cortex mediate auditory feedback control of speech. PMID:18035557 </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.A42C..08S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.A42C..08S">Landscape fires dominate terrestrial natural aerosol - climate feedbacks</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Scott, C.; Arnold, S.; Monks, S. A.; Asmi, A.; Paasonen, P.; Spracklen, D. V. 2017-12-01 The terrestrial biosphere is an important source of natural aerosol including landscape fire emissions and secondary organic aerosol (SOA) formed from biogenic volatile organic compounds (BVOCs). Atmospheric aerosol alters the Earth's climate by absorbing and scattering radiation (direct radiative effect; DRE) and by perturbing the properties of clouds (aerosol indirect effect; AIE). Natural aerosol sources are strongly controlled by, and can influence, climate; giving rise to potential natural aerosol-climate feedbacks. Earth System Models (ESMs) include a description of some of these natural aerosol-climate feedbacks, predicting substantial changes in natural aerosol over the coming century with associated radiative perturbations. Despite this, the sensitivity of natural aerosols simulated by ESMs to changes in climate or emissions has not been robustly tested against observations. Here we combine long-term observations of aerosol number and a global aerosol microphysics model to assess terrestrial natural aerosol-climate feedbacks. We find a strong positive relationship between the summertime anomaly in observed concentration of particles greater than 100 nm diameter and the anomaly in local air temperature. This relationship is reproduced by the model and driven by variability in dynamics and meteorology, as well as natural sources of aerosol. We use an offline radiative transfer model to determine radiative effects due to changes in two natural aerosol sources: landscape fire and biogenic SOA. We find that interannual variability in the simulated global natural aerosol radiative effect (RE) is negatively related to the global temperature anomaly. The magnitude of global aerosol-climate feedback (sum of DRE and AIE) is estimated to be -0.15 Wm-2 K-1 for landscape fire aerosol and -0.06 Wm-2 K-1 for biogenic SOA. These feedbacks are comparable in magnitude, but opposite in sign to the snow albedo feedback, highlighting the need for natural aerosol feedbacks to </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28811530','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28811530">Evidence for ice-ocean albedo feedback in the Arctic Ocean shifting to a seasonal ice zone.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Kashiwase, Haruhiko; Ohshima, Kay I; Nihashi, Sohey; Eicken, Hajo 2017-08-15 Ice-albedo feedback due to the albedo contrast between water and ice is a major factor in seasonal sea ice retreat, and has received increasing attention with the Arctic Ocean shifting to a seasonal ice cover. However, quantitative evaluation of such feedbacks is still insufficient. Here we provide quantitative evidence that heat input through the open water fraction is the primary driver of seasonal and interannual variations in Arctic sea ice retreat. Analyses of satellite data (1979-2014) and a simplified ice-upper ocean coupled model reveal that divergent ice motion in the early melt season triggers large-scale feedback which subsequently amplifies summer sea ice anomalies. The magnitude of divergence controlling the feedback has doubled since 2000 due to a more mobile ice cover, which can partly explain the recent drastic ice reduction in the Arctic Ocean. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.7407K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.7407K">Sea-level and solid-Earth deformation feedbacks in ice sheet modelling</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Konrad, Hannes; Sasgen, Ingo; Klemann, Volker; Thoma, Malte; Grosfeld, Klaus; Martinec, Zdeněk 2014-05-01 The interactions of ice sheets with the sea level and the solid Earth are important factors for the stability of the ice shelves and the tributary inland ice (e.g. Thomas and Bentley, 1978; Gomez et al, 2012). First, changes in ice extent and ice thickness induce viscoelastic deformation of the Earth surface and Earth's gravity field. In turn, global and local changes in sea level and bathymetry affect the grounding line and, subsequently, alter the ice dynamic behaviour. Here, we investigate these feedbacks for a synthetic ice sheet configuration as well as for the Antarctic ice sheet using a three-dimensional thermomechanical ice sheet and shelf model, coupled to a viscoelastic solid-Earth and gravitationally self-consistent sea-level model. The respective ice sheet undergoes a forcing from rising sea level, warming ocean, and/or changing surface mass balance. The coupling is realized by exchanging ice thickness, Earth surface deformation and sea level periodically. We apply several sets of viscoelastic Earth parameters to our coupled model, e.g. simulating a low-viscous upper mantle present at the Antarctic Peninsula (Ivins et al., 2011). Special focus of our study lies on the evolution of Earth surface deformation and local sea level changes, as well as on the accompanying grounding line evolution. N. Gomez, D. Pollard, J. X. Mitrovica, P. Huybers, and P. U. Clark 2012. Evolution of a coupled marine ice sheet-sea level model, J. Geophys. Res., 117, F01013, doi:10.1029/2011JF002128. E. R. Ivins, M. M. Watkins, D.-N. Yuan, R. Dietrich, G. Casassa, and A. Rülke 2011. On-land ice loss and glacial isostatic adjustment at the Drake Passage: 2003-2009, J. Geophys. Res. 116, B02403, doi: 10.1029/2010JB007607 R. H. Thomas and C. R. Bentley 1978. A model for Holocene retreat of the West Antarctic Ice Sheet, Quaternary Research, 10 (2), pages 150-170, doi: 10.1016/0033-5894(78)90098-4. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014ApJ...789..150G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014ApJ...789..150G">Active Galactic Nucleus Feedback in an Isolated Elliptical Galaxy: The Effect of Strong Radiative Feedback in the Kinetic Mode</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Gan, Zhaoming; Yuan, Feng; Ostriker, Jeremiah P.; Ciotti, Luca; Novak, Gregory S. 2014-07-01 Based on two-dimensional high-resolution hydrodynamic numerical simulation, we study the mechanical and radiative feedback effects from the central active galactic nucleus (AGN) on the cosmological evolution of an isolated elliptical galaxy. The inner boundary of the simulation domain is carefully chosen so that the fiducial Bondi radius is resolved and the accretion rate of the black hole is determined self-consistently. It is well known that when the accretion rates are high and low, the central AGNs will be in cold and hot accretion modes, which correspond to the radiative and kinetic feedback modes, respectively. The emitted spectrum from the hot accretion flows is harder than that from the cold accretion flows, which could result in a higher Compton temperature accompanied by a more efficient radiative heating, according to previous theoretical works. Such a difference of the Compton temperature between the two feedback modes, the focus of this study, has been neglected in previous works. Significant differences in the kinetic feedback mode are found as a result of the stronger Compton heating. More importantly, if we constrain models to correctly predict black hole growth and AGN duty cycle after cosmological evolution, we find that the favored model parameters are constrained: mechanical feedback efficiency diminishes with decreasing luminosity (the maximum efficiency being ~= 10-3.5), and X-ray Compton temperature increases with decreasing luminosity, although models with fixed mechanical efficiency and Compton temperature can be found that are satisfactory as well. We conclude that radiative feedback in the kinetic mode is much more important than previously thought. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29517523','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29517523">About Politeness, Face, and Feedback: Exploring Resident and Faculty Perceptions of How Institutional Feedback Culture Influences Feedback Practices.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Ramani, Subha; Könings, Karen D; Mann, Karen V; Pisarski, Emily E; van der Vleuten, Cees P M 2018-03-06 To explore resident and faculty perspectives on what constitutes feedback culture, their perceptions of how institutional feedback culture (including politeness concepts) might influence the quality and impact of feedback, feedback seeking, receptivity, and readiness to engage in bidirectional feedback. Using a constructivist grounded theory approach, five focus group discussions with internal medicine residents, three focus group discussions with general medicine faculty, and eight individual interviews with subspecialist faculty were conducted at Brigham and Women's Hospital between April and December 2016. Discussions and interviews were audiotaped and transcribed verbatim; concurrent data collection and analysis were performed using the constant comparative approach. Analysis was considered through the lens of politeness theory and organizational culture. Twenty-nine residents and twenty-two general medicine faculty participated in focus group discussions, and eight subspecialty faculty participated in interviews. The institutional feedback culture was described by participants as: (1) a culture of politeness, in which language potentially damaging to residents' self-esteem was discouraged, and (2) a culture of excellence, in which the institution's outstanding reputation and pedigree of trainees inhibited constructive feedback. Three key themes situated within this broader cultural context were discovered: normalizing constructive feedback to promote a culture of growth, overcoming the mental block to feedback seeking, and hierarchical culture impeding bidirectional feedback. An institutional feedback culture of excellence and politeness may impede honest, meaningful feedback and may impact feedback seeking, receptivity, and bidirectional feedback exchanges. It is essential to understand the institutional feedback culture before it can be successfully changed. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015CNSNS..22..747Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015CNSNS..22..747Z">Bifurcation analysis of a delay reaction-diffusion malware propagation model with feedback control</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Zhu, Linhe; Zhao, Hongyong; Wang, Xiaoming 2015-05-01 With the rapid development of network information technology, information networks security has become a very critical issue in our work and daily life. This paper attempts to develop a delay reaction-diffusion model with a state feedback controller to describe the process of malware propagation in mobile wireless sensor networks (MWSNs). By analyzing the stability and Hopf bifurcation, we show that the state feedback method can successfully be used to control unstable steady states or periodic oscillations. Moreover, formulas for determining the properties of the bifurcating periodic oscillations are derived by applying the normal form method and center manifold theorem. Finally, we conduct extensive simulations on large-scale MWSNs to evaluate the proposed model. Numerical evidences show that the linear term of the controller is enough to delay the onset of the Hopf bifurcation and the properties of the bifurcation can be regulated to achieve some desirable behaviors by choosing the appropriate higher terms of the controller. Furthermore, we obtain that the spatial-temporal dynamic characteristics of malware propagation are closely related to the rate constant for nodes leaving the infective class for recovered class and the mobile behavior of nodes. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28300384','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28300384">Quantitation of clinical feedback on image quality differences between two CT scanner models.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Bache, Steven T; Stauduhar, Paul J; Liu, Xinming; Loyer, Evelyne M; John, Rong X 2017-03-01 The aim of this work was to quantitate differences in image quality between two GE CT scanner models - the LightSpeed VCT ("VCT") and Discovery HD750 ("HD") - based upon feedback from radiologists at our institution. First, 3 yrs of daily QC images of the manufacturer-provided QC phantom from 10 scanners - five of each model - were analyzed for both noise magnitude, measured as CT-number standard deviation, and noise power spectrum within the uniform water section. The same phantom was then scanned on four of each model and analyzed for low contrast detectability (LCD) using a built-in LCD tool at the scanner console. An anthropomorphic phantom was scanned using the same eight scanners. A slice within the abdomen section was chosen and three ROIs were placed in regions representing liver, stomach, and spleen. Both standard deviation of CT-number and LCD value was calculated for each image. Noise magnitude was 8.5% higher in HD scanners compared to VCT scanners. An associated increase in the magnitude of the noise power spectra were also found, but both peak and mean NPS frequency were not different between the two models. VCT scanners outperformed HD scanners with respect to LCD by an average of 13.1% across all scanners and phantoms. Our results agree with radiologist feedback, and necessitate a closer look at our body CT protocols among different scanner models at our institution. © 2017 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20100017476','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20100017476">Analysis of Atmosphere-Ocean Surface Flux Feedbacks in Recent Satellite and Model Reanalysis Products</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Roberts, J. Brent; Robertson, F. R.; Clayson, C. A. 2010-01-01 Recent investigations have examined observations in an attempt to determine when and how the ocean forces the atmosphere, and vice versa. These studies focus primarily on relationships between sea surface temperature anomalies and the turbulent and radiative surface heat fluxes. It has been found that both positive and negative feedbacks, which enhance or reduce sea surface temperature anomaly amplitudes, can be generated through changes in the surface boundary layer. Consequent changes in sea surface temperature act to change boundary layer characteristics through changes in static stability or turbulent fluxes. Previous studies over the global oceans have used coarse-resolution observational and model products such as ICOADS and the NCEP Reanalysis. This study focuses on documenting the atmosphere ocean feedbacks that exist in recently produced higher resolution products, namely the SeaFlux v1.0 product and the NASA Modern Era Retrospective-Analysis for Research and Applications (MERRA). It has been noted in recent studies that evidence of oceanic forcing of the atmosphere exists on smaller scales than the usually more dominant atmospheric forcing of the ocean, particularly in higher latitudes. It is expected that use of these higher resolution products will allow for a more comprehensive description of these small-scale ocean-atmosphere feedbacks. The SeaFlux intercomparisons have revealed large scatter between various surface flux climatologies. This study also investigates the uncertainty in surface flux feedbacks based on several of these recent satellite based climatologies </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29221450','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29221450">Peer feedback for examiner quality assurance on MRCGP International South Asia: a mixed methods study.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Perera, D P; Andrades, Marie; Wass, Val 2017-12-08 The International Membership Examination (MRCGP[INT]) of the Royal College of General Practitioners UK is a unique collaboration between four South Asian countries with diverse cultures, epidemiology, clinical facilities and resources. In this setting good quality assurance is imperative to achieve acceptable standards of inter rater reliability. This study aims to explore the process of peer feedback for examiner quality assurance with regard to factors affecting the implementation and acceptance of the method. A sequential mixed methods approach was used based on focus group discussions with examiners (n = 12) and clinical examination convenors who acted as peer reviewers (n = 4). A questionnaire based on emerging themes and literature review was then completed by 20 examiners at the subsequent OSCE exam. Qualitative data were analysed using an iterative reflexive process. Quantitative data were integrated by interpretive analysis looking for convergence, complementarity or dissonance. The qualitative data helped understand the issues and informed the process of developing the questionnaire. The quantitative data allowed for further refining of issues, wider sampling of examiners and giving voice to different perspectives. Examiners stated specifically that peer feedback gave an opportunity for discussion, standardisation of judgments and improved discriminatory abilities. Interpersonal dynamics, hierarchy and perception of validity of feedback were major factors influencing acceptance of feedback. Examiners desired increased transparency, accountability and the opportunity for equal partnership within the process. The process was stressful for examiners and reviewers; however acceptance increased with increasing exposure to receiving feedback. The process could be refined to improve acceptability through scrupulous attention to training and selection of those giving feedback to improve the perceived validity of feedback and improved reviewer feedback </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.7501C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.7501C">Feedbacks in human-landscape systems</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Chin, Anne 2015-04-01 As human interactions with Earth systems intensify in the "Anthropocene", understanding the complex relationships among human activity, landscape change, and societal responses to those changes is increasingly important. Interdisciplinary research centered on the theme of "feedbacks" in human-landscape systems serves as a promising focus for unraveling these interactions. Deciphering interacting human-landscape feedbacks extends our traditional approach of considering humans as unidirectional drivers of change. Enormous challenges exist, however, in quantifying impact-feedback loops in landscapes with significant human alterations. This paper illustrates an example of human-landscape interactions following a wildfire in Colorado (USA) that elicited feedback responses. After the 2012 Waldo Canyon Fire, concerns for heightened flood potential and debris flows associated with post-fire hydrologic changes prompted local landowners to construct tall fences at the base of a burned watershed. These actions changed the sediment transport regime and promoted further landscape change and human responses in a positive feedback cycle. The interactions ultimately increase flood and sediment hazards, rather than dampening the effects of fire. A simple agent-based model, capable of integrating social and hydro-geomorphological data, demonstrates how such interacting impacts and feedbacks could be simulated. Challenges for fully capturing human-landscape feedback interactions include the identification of diffuse and subtle feedbacks at a range of scales, the availability of data linking impact with response, the identification of multiple thresholds that trigger feedback mechanisms, and the varied metrics and data needed to represent both the physical and human systems. By collaborating with social scientists with expertise in the human causes of landscape change, as well as the human responses to those changes, geoscientists could more fully recognize and anticipate the coupled </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3125197','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3125197">Feedback Enhances Feedforward Figure-Ground Segmentation by Changing Firing Mode</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Supèr, Hans; Romeo, August 2011-01-01 In the visual cortex, feedback projections are conjectured to be crucial in figure-ground segregation. However, the precise function of feedback herein is unclear. Here we tested a hypothetical model of reentrant feedback. We used a previous developed 2-layered feedforwardspiking network that is able to segregate figure from ground and included feedback connections. Our computer model data show that without feedback, neurons respond with regular low-frequency (∼9 Hz) bursting to a figure-ground stimulus. After including feedback the firing pattern changed into a regular (tonic) spiking pattern. In this state, we found an extra enhancement of figure responses and a further suppression of background responses resulting in a stronger figure-ground signal. Such push-pull effect was confirmed by comparing the figure-ground responses withthe responses to a homogenous texture. We propose that feedback controlsfigure-ground segregation by influencing the neural firing patterns of feedforward projecting neurons. PMID:21738747 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21738747','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21738747">Feedback enhances feedforward figure-ground segmentation by changing firing mode.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Supèr, Hans; Romeo, August 2011-01-01 In the visual cortex, feedback projections are conjectured to be crucial in figure-ground segregation. However, the precise function of feedback herein is unclear. Here we tested a hypothetical model of reentrant feedback. We used a previous developed 2-layered feedforward spiking network that is able to segregate figure from ground and included feedback connections. Our computer model data show that without feedback, neurons respond with regular low-frequency (∼9 Hz) bursting to a figure-ground stimulus. After including feedback the firing pattern changed into a regular (tonic) spiking pattern. In this state, we found an extra enhancement of figure responses and a further suppression of background responses resulting in a stronger figure-ground signal. Such push-pull effect was confirmed by comparing the figure-ground responses with the responses to a homogenous texture. We propose that feedback controls figure-ground segregation by influencing the neural firing patterns of feedforward projecting neurons. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015CNSNS..23...78P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015CNSNS..23...78P">A stage structure pest management model with impulsive state feedback control</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Pang, Guoping; Chen, Lansun; Xu, Weijian; Fu, Gang 2015-06-01 A stage structure pest management model with impulsive state feedback control is investigated. We get the sufficient condition for the existence of the order-1 periodic solution by differential equation geometry theory and successor function. Further, we obtain a new judgement method for the stability of the order-1 periodic solution of the semi-continuous systems by referencing the stability analysis for limit cycles of continuous systems, which is different from the previous method of analog of Poincarè criterion. Finally, we analyze numerically the theoretical results obtained. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19900016212','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19900016212">The human factors of workstation telepresence</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Smith, Thomas J.; Smith, Karl U. 1990-01-01 The term workstation telepresence has been introduced to describe human-telerobot compliance, which enables the human operator to effectively project his/her body image and behavioral skills to control of the telerobot itself. Major human-factors considerations for establishing high fidelity workstation telepresence during human-telerobot operation are discussed. Telerobot workstation telepresence is defined by the proficiency and skill with which the operator is able to control sensory feedback from direct interaction with the workstation itself, and from workstation-mediated interaction with the telerobot. Numerous conditions influencing such control have been identified. This raises the question as to what specific factors most critically influence the realization of high fidelity workstation telepresence. The thesis advanced here is that perturbations in sensory feedback represent a major source of variability in human performance during interactive telerobot operation. Perturbed sensory feedback research over the past three decades has established that spatial transformations or temporal delays in sensory feedback engender substantial decrements in interactive task performance, which training does not completely overcome. A recently developed social cybernetic model of human-computer interaction can be used to guide this approach, based on computer-mediated tracking and control of sensory feedback. How the social cybernetic model can be employed for evaluating the various modes, patterns, and integrations of interpersonal, team, and human-computer interactions which play a central role is workstation telepresence are discussed. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUOSME24B0704H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUOSME24B0704H">An Integrative, Multi-Scale Computational Model of a Swimming Lamprey Fully Coupled to Its Fluid Environment and Incorporating Proprioceptive Feedback</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Hamlet, C. L.; Hoffman, K.; Fauci, L.; Tytell, E. 2016-02-01 The lamprey is a model organism for both neurophysiology and locomotion studies. To study the role of sensory feedback as an organism moves through its environment, a 2D, integrative, multi-scale model of an anguilliform swimmer driven by neural activation from a central pattern generator (CPG) is constructed. The CPG in turn drives muscle kinematics and is fully coupled to the surrounding fluid. The system is numerically evolved in time using an immersed boundary framework producing an emergent swimming mode. Proprioceptive feedback to the CPG based on experimental observations adjust the activation signal as the organism interacts with its environment. Effects on the speed, stability and cost (metabolic work) of swimming due to nonlinear dependencies associated with muscle force development combined with proprioceptive feedback to neural activation are estimated and examined. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.B53J..06T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.B53J..06T">Biospheric feedback effects in a synchronously coupled model of human and Earth systems</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Thornton, P. E.; Calvin, K. V.; Jones, A. D.; Di Vittorio, A. V.; Bond-Lamberty, B. P.; Chini, L. P.; Shi, X.; Mao, J.; Collins, W. D.; Edmonds, J.; Hurtt, G. C. 2017-12-01 Fossil fuel combustion and land-use change are the two largest contributors to industrial-era increases in atmospheric CO2 concentration. Projections of these are thus fundamental inputs for coupled Earth system models (ESMs) used to estimate the physical and biological consequences of future climate system forcing. While historical datasets are available to inform past and current climate analyses, assessments of future climate change have relied on projections of energy and land use from energy economic models, constrained by assumptions about future policy, land-use patterns, and socio-economic development trajectories. In this work we show that the climatic impacts on land ecosystems drives significant feedbacks in energy, agriculture, land-use, and carbon cycle projections for the 21st century. We find that exposure of human appropriated land ecosystem productivity to biospheric change results in reductions of land area used for crops; increases in managed forest area and carbon stocks; decreases in global crop prices; and reduction in fossil fuel emissions for a low-mid range forcing scenario. Land ecosystem response to increased carbon dioxide concentration, increased anthropogenic nitrogen deposition, and changes in temperature and precipitation all play a role. The feedbacks between climate-induced biospheric change and human system forcings to the climate system demonstrated in this work are handled inconsistently, or excluded altogether, in the one-way asynchronous coupling of energy economic models to ESMs used to date. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17240397','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17240397">Biodiversity maintenance in food webs with regulatory environmental feedbacks.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Bagdassarian, Carey K; Dunham, Amy E; Brown, Christopher G; Rauscher, Daniel 2007-04-21 Although the food web is one of the most fundamental and oldest concepts in ecology, elucidating the strategies and structures by which natural communities of species persist remains a challenge to empirical and theoretical ecologists. We show that simple regulatory feedbacks between autotrophs and their environment when embedded within complex and realistic food-web models enhance biodiversity. The food webs are generated through the niche-model algorithm and coupled with predator-prey dynamics, with and without environmental feedbacks at the autotroph level. With high probability and especially at lower, more realistic connectance levels, regulatory environmental feedbacks result in fewer species extinctions, that is, in increased species persistence. These same feedback couplings, however, also sensitize food webs to environmental stresses leading to abrupt collapses in biodiversity with increased forcing. Feedback interactions between species and their material environments anchor food-web persistence, adding another dimension to biodiversity conservation. We suggest that the regulatory features of two natural systems, deep-sea tubeworms with their microbial consortia and a soil ecosystem manifesting adaptive homeostatic changes, can be embedded within niche-model food-web dynamics. </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active">16</li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active">17</li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017IJSS...48.1932P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017IJSS...48.1932P">A new modelling and identification scheme for time-delay systems with experimental investigation: a relay feedback approach</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Pandey, Saurabh; Majhi, Somanath; Ghorai, Prasenjit 2017-07-01 In this paper, the conventional relay feedback test has been modified for modelling and identification of a class of real-time dynamical systems in terms of linear transfer function models with time-delay. An ideal relay and unknown systems are connected through a negative feedback loop to bring the sustained oscillatory output around the non-zero setpoint. Thereafter, the obtained limit cycle information is substituted in the derived mathematical equations for accurate identification of unknown plants in terms of overdamped, underdamped, critically damped second-order plus dead time and stable first-order plus dead time transfer function models. Typical examples from the literature are included for the validation of the proposed identification scheme through computer simulations. Subsequently, the comparisons between estimated model and true system are drawn through integral absolute error criterion and frequency response plots. Finally, the obtained output responses through simulations are verified experimentally on real-time liquid level control system using Yokogawa Distributed Control System CENTUM CS3000 set up. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.C31A0734W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.C31A0734W">Spring snow albedo feedback in daily data over Russia: Comparing in-situ measurements with reanalysis products.</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Wegmann, M.; Zolina, O.; Jacobi, H. W. 2016-12-01 Global warming is enhanced at high northern latitudes where the Arctic surface air temperature has risen at twice the rate of the global average in recent decades - a feature called Arctic amplification. This recent Arctic warming signal likely results from several factors such as the albedo feedback due to a diminishing cryosphere, enhanced poleward atmospheric and oceanic heat transport, and changes in humidity. Surface albedo feedback is stating that the additional amount of shortwave radiation at the top of the atmosphere decreases with decreasing surface albedo whereas surface air temperature increases with decreasing surface albedo. It is considered a positive feedback in that an initial warming perturbation than kicks off a strengthening warming. Looking at the Northern Hemisphere with its large landmasses, snow albedo feedback is especially strong since most of these landmasses experience snow cover during boreal wintertime. Unfortunately, so far there remains a lack of reliable observational data over large parts of the cryosphere. Satellite products cover large parts of the NH, however lack high temporal resolution and have problems with large solar zenith angles as well as over complex terrain (eg. Wang et al. 2014). Our analysis focuses at the Russian territory where we utilize in-situ radiation and snow depth measurements. We found 50 stations which measure both variables on a daily basis for the period 2000-2013. Since Hall (2004) found that 50% of the notal NH snow albedo feedback caused by global warming occurs during NH spring, we focus on the transition period of March to June (MAMJ). Thackeray & Fletcher 2006 compared albedo feedback processes CMIP3 and CMIP5 model families and found while the models represent the feedback process accurately, there are still inherent biases and outdated parameterizations. Therefore we use the daily observations and state of the art reanalysis products to 1) evaluate reanalysis and model products in respect to </li> <li> <a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/EJ1097542.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/EJ1097542.pdf">Learning to Swim Using Video Modelling and Video Feedback within a Self-Management Program</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Lao, So-An; Furlonger, Brett E.; Moore, Dennis W.; Busacca, Margherita 2016-01-01 Although many adults who cannot swim are primarily interested in learning by direct coaching there are options that have a focus on self-directed learning. As an alternative a self-management program combined with video modelling, video feedback and high quality and affordable video technology was used to assess its effectiveness to assisting an… </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMGC31B1124M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMGC31B1124M">Integrated modeling of land-use change: the role of coupling, interactions and feedbacks between the human and Earth systems</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Monier, E.; Kicklighter, D. W.; Ejaz, Q.; Winchester, N.; Paltsev, S.; Reilly, J. M. 2016-12-01 Land-use change integrates a large number of components of the human and Earth systems, including climate, energy, water, and land. These complex coupling elements, interactions and feedbacks take place on a variety of space and time scales, thus increasing the complexity of land-use change modeling frameworks. In this study, we aim to identify which coupling elements, interactions and feedbacks are important for modeling land-use change, both at the global and regional level. First, we review the existing land-use change modeling framework used to develop land-use change projections for the Representative Concentration Pathways (RCP) scenarios. In such framework, land-use change is simulated by Integrated Assessment Models (IAMs) and mainly influenced by economic, energy, demographic and policy drivers. IAMs focus on representing the demand for agriculture and forestry goods (crops for food and bioenergy, forest products for construction and bioenergy), the interactions with other sectors of the economy and trade between various regions of the world. Then, we investigate how important various coupling elements and feedbacks with the Earth system are for projections of land-use change at the global and regional level. We focus on the following: i) the climate impacts on land productivity and greenhouse gas emissions, which requires climate change information and coupling to a terrestrial ecosystem model/crop model; ii) the climate and economic impacts on irrigation availability, which requires coupling the LUC modeling framework to a water resources management model and disaggregating rainfed and irrigated croplands; iii) the feedback of land-use change on the global and regional climate system through land-use change emissions and changes in the surface albedo and hydrology, which requires coupling to an Earth system model. Finally, we conclude our study by highlighting the current lack of clarity in how various components of the human and Earth systems are </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRC..121.7326Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRC..121.7326Z">A modulating effect of Tropical Instability Wave (TIW)-induced surface wind feedback in a hybrid coupled model of the tropical Pacific</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Zhang, Rong-Hua 2016-10-01 Tropical Instability Waves (TIWs) and the El Niño-Southern Oscillation (ENSO) are two air-sea coupling phenomena that are prominent in the tropical Pacific, occurring at vastly different space-time scales. It has been challenging to adequately represent both of these processes within a large-scale coupled climate model, which has led to a poor understanding of the interactions between TIW-induced feedback and ENSO. In this study, a novel modeling system was developed that allows representation of TIW-scale air-sea coupling and its interaction with ENSO. Satellite data were first used to derive an empirical model for TIW-induced sea surface wind stress perturbations (τTIW). The model was then embedded in a basin-wide hybrid-coupled model (HCM) of the tropical Pacific. Because τTIW were internally determined from TIW-scale sea surface temperatures (SSTTIW) simulated in the ocean model, the wind-SST coupling at TIW scales was interactively represented within the large-scale coupled model. Because the τTIW-SSTTIW coupling part of the model can be turned on or off in the HCM simulations, the related TIW wind feedback effects can be isolated and examined in a straightforward way. Then, the TIW-scale wind feedback effects on the large-scale mean ocean state and interannual variability in the tropical Pacific were investigated based on this embedded system. The interactively represented TIW-scale wind forcing exerted an asymmetric influence on SSTs in the HCM, characterized by a mean-state cooling and by a positive feedback on interannual variability, acting to enhance ENSO amplitude. Roughly speaking, the feedback tends to increase interannual SST variability by approximately 9%. Additionally, there is a tendency for TIW wind to have an effect on the phase transition during ENSO evolution, with slightly shortened interannual oscillation periods. Additional sensitivity experiments were performed to elucidate the details of TIW wind effects on SST evolution during ENSO </li> <li> <a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19910041575&hterms=current+feedback&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dcurrent%2Bfeedback','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19910041575&hterms=current+feedback&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dcurrent%2Bfeedback">Positive water vapour feedback in climate models confirmed by satellite data</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Rind, D.; Lerner, J.; Chiou, E.-W.; Chu, W.; Larsen, J.; Mccormick, M. P.; Mcmaster, L. 1991-01-01 It has recently been suggested that GCMs used to evaluate climate change overestimate the greenhouse effect due to increased concentrations of trace gases in the atmosphere. Here, new satellite-generated water vapor data are used to compare summer and winter moisture values in regions of the middle and upper troposphere that have previously been difficult to observe with confidence. It is found that, as the hemispheres warm, increased convection leads to increased water vapor above 500 mbar in approximate quantitative agreement with results from current climate models. The same conclusion is reached by comparing the tropical western and eastern Pacific regions. Thus, water vapor feedback is not overestimated in models and should amplify the climate response to increased trace-gas concentrations. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017IJSS...48.1891Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017IJSS...48.1891Z">Non-fragile observer-based output feedback control for polytopic uncertain system under distributed model predictive control approach</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Zhu, Kaiqun; Song, Yan; Zhang, Sunjie; Zhong, Zhaozhun 2017-07-01 In this paper, a non-fragile observer-based output feedback control problem for the polytopic uncertain system under distributed model predictive control (MPC) approach is discussed. By decomposing the global system into some subsystems, the computation complexity is reduced, so it follows that the online designing time can be saved.Moreover, an observer-based output feedback control algorithm is proposed in the framework of distributed MPC to deal with the difficulties in obtaining the states measurements. In this way, the presented observer-based output-feedback MPC strategy is more flexible and applicable in practice than the traditional state-feedback one. What is more, the non-fragility of the controller has been taken into consideration in favour of increasing the robustness of the polytopic uncertain system. After that, a sufficient stability criterion is presented by using Lyapunov-like functional approach, meanwhile, the corresponding control law and the upper bound of the quadratic cost function are derived by solving an optimisation subject to convex constraints. Finally, some simulation examples are employed to show the effectiveness of the method. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22277888-modeling-laser-induced-periodic-surface-structures-finite-difference-time-domain-feedback-simulations','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22277888-modeling-laser-induced-periodic-surface-structures-finite-difference-time-domain-feedback-simulations">Modeling laser-induced periodic surface structures: Finite-difference time-domain feedback simulations</a> <a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a> Skolski, J. Z. P., E-mail: j.z.p.skolski@utwente.nl; Vincenc Obona, J.; Römer, G. R. B. E. 2014-03-14 A model predicting the formation of laser-induced periodic surface structures (LIPSSs) is presented. That is, the finite-difference time domain method is used to study the interaction of electromagnetic fields with rough surfaces. In this approach, the rough surface is modified by “ablation after each laser pulse,” according to the absorbed energy profile, in order to account for inter-pulse feedback mechanisms. LIPSSs with a periodicity significantly smaller than the laser wavelength are found to “grow” either parallel or orthogonal to the laser polarization. The change in orientation and periodicity follow from the model. LIPSSs with a periodicity larger than the wavelengthmore » of the laser radiation and complex superimposed LIPSS patterns are also predicted by the model.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28992943','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28992943">Perturbed cooperative-state feedback strategy for model predictive networked control of interconnected systems.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Tran, Tri; Ha, Q P 2018-01-01 A perturbed cooperative-state feedback (PSF) strategy is presented for the control of interconnected systems in this paper. The subsystems of an interconnected system can exchange data via the communication network that has multiple connection topologies. The PSF strategy can resolve both issues, the sensor data losses and the communication network breaks, thanks to the two components of the control including a cooperative-state feedback and a perturbation variable, e.g., u i =K ij x j +w i . The PSF is implemented in a decentralized model predictive control scheme with a stability constraint and a non-monotonic storage function (ΔV(x(k))≥0), derived from the dissipative systems theory. Numerical simulation for the automatic generation control problem in power systems is studied to illustrate the effectiveness of the presented PSF strategy. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23141878','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23141878">Reserve selection with land market feedbacks.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Butsic, Van; Lewis, David J; Radeloff, Volker C 2013-01-15 How to best site reserves is a leading question for conservation biologists. Recently, reserve selection has emphasized efficient conservation: maximizing conservation goals given the reality of limited conservation budgets, and this work indicates that land market can potentially undermine the conservation benefits of reserves by increasing property values and development probabilities near reserves. Here we propose a reserve selection methodology which optimizes conservation given both a budget constraint and land market feedbacks by using a combination of econometric models along with stochastic dynamic programming. We show that amenity based feedbacks can be accounted for in optimal reserve selection by choosing property price and land development models which exogenously estimate the effects of reserve establishment. In our empirical example, we use previously estimated models of land development and property prices to select parcels to maximize coarse woody debris along 16 lakes in Vilas County, WI, USA. Using each lake as an independent experiment, we find that including land market feedbacks in the reserve selection algorithm has only small effects on conservation efficacy. Likewise, we find that in our setting heuristic (minloss and maxgain) algorithms perform nearly as well as the optimal selection strategy. We emphasize that land market feedbacks can be included in optimal reserve selection; the extent to which this improves reserve placement will likely vary across landscapes. Copyright © 2012 Elsevier Ltd. All rights reserved. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=reduce+AND+turnover&pg=5&id=EJ108683','ERIC'); return false;" href="https://eric.ed.gov/?q=reduce+AND+turnover&pg=5&id=EJ108683">Feedback & Objectives</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Butterworth, James R. 1975-01-01 Industrial objectives, if they are employee oriented, produce feedback, and the motivation derived from the feedback helps reduce turnover. Feedback is the power to clarify objectives, to stimulate communication, and to motivate people. (Author/MW) </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JPhCS1007a2001P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JPhCS1007a2001P">Overview Electrotactile Feedback for Enhancing Human Computer Interface</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Pamungkas, Daniel S.; Caesarendra, Wahyu 2018-04-01 To achieve effective interaction between a human and a computing device or machine, adequate feedback from the computing device or machine is required. Recently, haptic feedback is increasingly being utilised to improve the interactivity of the Human Computer Interface (HCI). Most existing haptic feedback enhancements aim at producing forces or vibrations to enrich the user’s interactive experience. However, these force and/or vibration actuated haptic feedback systems can be bulky and uncomfortable to wear and only capable of delivering a limited amount of information to the user which can limit both their effectiveness and the applications they can be applied to. To address this deficiency, electrotactile feedback is used. This involves delivering haptic sensations to the user by electrically stimulating nerves in the skin via electrodes placed on the surface of the skin. This paper presents a review and explores the capability of electrotactile feedback for HCI applications. In addition, a description of the sensory receptors within the skin for sensing tactile stimulus and electric currents alsoseveral factors which influenced electric signal to transmit to the brain via human skinare explained. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19880050737&hterms=greenhouse+effect&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dgreenhouse%2Beffect','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19880050737&hterms=greenhouse+effect&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dgreenhouse%2Beffect">Cloud-radiation interactions - Effects of cirrus optical thickness feedbacks</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Somerville, Richard C. J.; Iacobellis, Sam 1987-01-01 The paper is concerned with a cloud-radiation feedback mechanism which may be an important component of the climate changes expected from increased atmospheric concentrations of carbon dioxide and other trace greenhouse gases. A major result of the study is that cirrus cloud optical thickness feedbacks may indeed tend to increase the surface warming due to trace gas increases. However, the positive feedback from cirrus appears to be generally weaker than the negative effects due to lower clouds. The results just confirm those of earlier research indicating that the net effect of cloud optical thickness feedbacks may be a negative feedback which may substantially (by a factor of about 2) reduce the surface warming due to the doubling of CO2, even in the presence of cirrus clouds. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=competence+AND+fear&pg=4&id=EJ955626','ERIC'); return false;" href="https://eric.ed.gov/?q=competence+AND+fear&pg=4&id=EJ955626">Factors Influencing Responsiveness to Feedback: On the Interplay between Fear, Confidence, and Reasoning Processes</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Eva, Kevin W.; Armson, Heather; Holmboe, Eric; Lockyer, Jocelyn; Loney, Elaine; Mann, Karen; Sargeant, Joan 2012-01-01 Self-appraisal has repeatedly been shown to be inadequate as a mechanism for performance improvement. This has placed greater emphasis on understanding the processes through which self-perception and external feedback interact to influence professional development. As feedback is inevitably interpreted through the lens of one's self-perceptions it… </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ResPh...9..609A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ResPh...9..609A">Semi-analytical solutions of the Schnakenberg model of a reaction-diffusion cell with feedback</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Al Noufaey, K. S. 2018-06-01 This paper considers the application of a semi-analytical method to the Schnakenberg model of a reaction-diffusion cell. The semi-analytical method is based on the Galerkin method which approximates the original governing partial differential equations as a system of ordinary differential equations. Steady-state curves, bifurcation diagrams and the region of parameter space in which Hopf bifurcations occur are presented for semi-analytical solutions and the numerical solution. The effect of feedback control, via altering various concentrations in the boundary reservoirs in response to concentrations in the cell centre, is examined. It is shown that increasing the magnitude of feedback leads to destabilization of the system, whereas decreasing this parameter to negative values of large magnitude stabilizes the system. The semi-analytical solutions agree well with numerical solutions of the governing equations. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1785251','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1785251">Corticothalamic feedback enhances stimulus response precision in the visual system</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Andolina, Ian M.; Jones, Helen E.; Wang, Wei; Sillito, Adam M. 2007-01-01 There is a tightly coupled bidirectional interaction between visual cortex and visual thalamus [lateral geniculate nucleus (LGN)]. Using drifting sinusoidal grating stimuli, we compared the response of cells in the LGN with and without feedback from the visual cortex. Raster plots revealed a striking difference in the response pattern of cells with and without feedback. This difference was reflected in the results from computing vector sum plots and the ratio of zero harmonic to the fundamental harmonic of the fast Fourier transform (FFT) for these responses. The variability of responses assessed by using the Fano factor was also different for the two groups, with the cells without feedback showing higher variability. We examined the covariance of these measures between pairs of simultaneously recorded cells with and without feedback, and they were much more strongly positively correlated with feedback. We constructed orientation tuning curves from the central 5 ms in the raw cross-correlograms of the outputs of pairs of LGN cells, and these curves revealed much sharper tuning with feedback. We discuss the significance of these data for cortical function and suggest that the precision in stimulus-linked firing in the LGN appears as an emergent factor from the corticothalamic interaction. PMID:17237220 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3950218','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3950218">Spatial Climate Patterns Explain Negligible Variation in Strength of Compensatory Density Feedbacks in Birds and Mammals</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Herrando-Pérez, Salvador; Delean, Steven; Brook, Barry W.; Cassey, Phillip; Bradshaw, Corey J. A. 2014-01-01 The use of long-term population data to separate the demographic role of climate from density-modified demographic processes has become a major topic of ecological investigation over the last two decades. Although the ecological and evolutionary mechanisms that determine the strength of density feedbacks are now well understood, the degree to which climate gradients shape those processes across taxa and broad spatial scales remains unclear. Intuitively, harsh or highly variable environmental conditions should weaken compensatory density feedbacks because populations are hypothetically unable to achieve or maintain densities at which social and trophic interactions (e.g., competition, parasitism, predation, disease) might systematically reduce population growth. Here we investigate variation in the strength of compensatory density feedback, from long-term time series of abundance over 146 species of birds and mammals, in response to spatial gradients of broad-scale temperature precipitation variables covering 97 localities in 28 countries. We use information-theoretic metrics to rank phylogenetic generalized least-squares regression models that control for sample size (time-series length) and phylogenetic non-independence. Climatic factors explained < 1% of the remaining variation in density-feedback strength across species, with the highest non-control, model-averaged effect sizes related to extreme precipitation variables. We could not link our results directly to other published studies, because ecologists use contrasting responses, predictors and statistical approaches to correlate density feedback and climate – at the expense of comparability in a macroecological context. Censuses of multiple populations within a given species, and a priori knowledge of the spatial scales at which density feedbacks interact with climate, seem to be necessary to determine cross-taxa variation in this phenomenon. Despite the availability of robust modelling tools, the </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24618822','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24618822">Spatial climate patterns explain negligible variation in strength of compensatory density feedbacks in birds and mammals.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Herrando-Pérez, Salvador; Delean, Steven; Brook, Barry W; Cassey, Phillip; Bradshaw, Corey J A 2014-01-01 The use of long-term population data to separate the demographic role of climate from density-modified demographic processes has become a major topic of ecological investigation over the last two decades. Although the ecological and evolutionary mechanisms that determine the strength of density feedbacks are now well understood, the degree to which climate gradients shape those processes across taxa and broad spatial scales remains unclear. Intuitively, harsh or highly variable environmental conditions should weaken compensatory density feedbacks because populations are hypothetically unable to achieve or maintain densities at which social and trophic interactions (e.g., competition, parasitism, predation, disease) might systematically reduce population growth. Here we investigate variation in the strength of compensatory density feedback, from long-term time series of abundance over 146 species of birds and mammals, in response to spatial gradients of broad-scale temperature precipitation variables covering 97 localities in 28 countries. We use information-theoretic metrics to rank phylogenetic generalized least-squares regression models that control for sample size (time-series length) and phylogenetic non-independence. Climatic factors explained < 1% of the remaining variation in density-feedback strength across species, with the highest non-control, model-averaged effect sizes related to extreme precipitation variables. We could not link our results directly to other published studies, because ecologists use contrasting responses, predictors and statistical approaches to correlate density feedback and climate--at the expense of comparability in a macroecological context. Censuses of multiple populations within a given species, and a priori knowledge of the spatial scales at which density feedbacks interact with climate, seem to be necessary to determine cross-taxa variation in this phenomenon. Despite the availability of robust modelling tools, the appropriate </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRD..123.1079X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRD..123.1079X">Modeling East Asian Dust and Its Radiative Feedbacks in CAM4-BAM</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Xie, Xiaoning; Liu, Xiaodong; Che, Huizheng; Xie, Xiaoxun; Wang, Hongli; Li, Jiandong; Shi, Zhengguo; Liu, Yangang 2018-01-01 East Asian dust and its radiative feedbacks are analyzed by the use of the fourth version of the Community Atmosphere Model (CAM4) with a bulk aerosol model parameterization (BAM) for the dust size distribution (CAM4-BAM). Two numerical experiments are conducted and intercompared: one with (Active) and one without (Passive) the radiative effects of dust aerosols. This CAM4-BAM captures the main spatial distribution of the dust aerosol optical depth (AOD) and the dust surface concentrations over East Asia, with positive correlations with the local observational data on annual and seasonal means. A comparative analysis of the Active and Passive experiments reveals that consideration of the dust-radiation interaction can significantly reduce dust emissions, loading, transport, and dry and wet depositions over East Asia, which is opposite to the enhanced dust cycle over North Africa. Further analysis of the contrasting dust-radiation feedbacks between North Africa and East Asia shows that over North Africa, the dust radiative forcing significantly increases the surface temperature and 10 m wind speed, whereas it decreases the surface temperature and the surface wind speeds over East Asia. These contrasting radiative effects, in turn, result in distinct dust cycle changes over these two regions. Mechanistic analysis reveals that the radiative contrasts between East Asia and North Africa are mainly due to the differences in their regional surface albedo, dust vertical distribution, and size distribution. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17067787','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17067787">Learning receptive fields using predictive feedback.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Jehee, Janneke F M; Rothkopf, Constantin; Beck, Jeffrey M; Ballard, Dana H 2006-01-01 Previously, it was suggested that feedback connections from higher- to lower-level areas carry predictions of lower-level neural activities, whereas feedforward connections carry the residual error between the predictions and the actual lower-level activities [Rao, R.P.N., Ballard, D.H., 1999. Nature Neuroscience 2, 79-87.]. A computational model implementing the hypothesis learned simple cell receptive fields when exposed to natural images. Here, we use predictive feedback to explain tuning properties in medial superior temporal area (MST). We implement the hypothesis using a new, biologically plausible, algorithm based on matching pursuit, which retains all the features of the previous implementation, including its ability to efficiently encode input. When presented with natural images, the model developed receptive field properties as found in primary visual cortex. In addition, when exposed to visual motion input resulting from movements through space, the model learned receptive field properties resembling those in MST. These results corroborate the idea that predictive feedback is a general principle used by the visual system to efficiently encode natural input. </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active">17</li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active">18</li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22365686-active-galactic-nucleus-feedback-isolated-elliptical-galaxy-effect-strong-radiative-feedback-kinetic-mode','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22365686-active-galactic-nucleus-feedback-isolated-elliptical-galaxy-effect-strong-radiative-feedback-kinetic-mode">Active galactic nucleus feedback in an isolated elliptical galaxy: The effect of strong radiative feedback in the kinetic mode</a> <a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a> Gan, Zhaoming; Yuan, Feng; Ostriker, Jeremiah P. 2014-07-10 Based on two-dimensional high-resolution hydrodynamic numerical simulation, we study the mechanical and radiative feedback effects from the central active galactic nucleus (AGN) on the cosmological evolution of an isolated elliptical galaxy. The inner boundary of the simulation domain is carefully chosen so that the fiducial Bondi radius is resolved and the accretion rate of the black hole is determined self-consistently. It is well known that when the accretion rates are high and low, the central AGNs will be in cold and hot accretion modes, which correspond to the radiative and kinetic feedback modes, respectively. The emitted spectrum from the hotmore » accretion flows is harder than that from the cold accretion flows, which could result in a higher Compton temperature accompanied by a more efficient radiative heating, according to previous theoretical works. Such a difference of the Compton temperature between the two feedback modes, the focus of this study, has been neglected in previous works. Significant differences in the kinetic feedback mode are found as a result of the stronger Compton heating. More importantly, if we constrain models to correctly predict black hole growth and AGN duty cycle after cosmological evolution, we find that the favored model parameters are constrained: mechanical feedback efficiency diminishes with decreasing luminosity (the maximum efficiency being ≅ 10{sup –3.5}), and X-ray Compton temperature increases with decreasing luminosity, although models with fixed mechanical efficiency and Compton temperature can be found that are satisfactory as well. We conclude that radiative feedback in the kinetic mode is much more important than previously thought.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26438281','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26438281">Shortwave forcing and feedbacks in Last Glacial Maximum and Mid-Holocene PMIP3 simulations.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Braconnot, Pascale; Kageyama, Masa 2015-11-13 Simulations of the climates of the Last Glacial Maximum (LGM), 21 000 years ago, and of the Mid-Holocene (MH), 6000 years ago, allow an analysis of climate feedbacks in climate states that are radically different from today. The analyses of cloud and surface albedo feedbacks show that the shortwave cloud feedback is a major driver of differences between model results. Similar behaviours appear when comparing the LGM and MH simulated changes, highlighting the fingerprint of model physics. Even though the different feedbacks show similarities between the different climate periods, the fact that their relative strength differs from one climate to the other prevents a direct comparison of past and future climate sensitivity. The land-surface feedback also shows large disparities among models even though they all produce positive sea-ice and snow feedbacks. Models have very different sensitivities when considering the vegetation feedback. This feedback has a regional pattern that differs significantly between models and depends on their level of complexity and model biases. Analyses of the MH climate in two versions of the IPSL model provide further indication on the possibilities to assess the role of model biases and model physics on simulated climate changes using past climates for which observations can be used to assess the model results. © 2015 The Author(s). </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28275362','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28275362">Impact of the Supervisor Feedback Environment on Creative Performance: A Moderated Mediation Model.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Zhang, Jian; Gong, Zhenxing; Zhang, Shuangyu; Zhao, Yujia 2017-01-01 Studies on the relationship between feedback and creative performance have only focused on the feedback-self and have underestimated the value of the feedback environment. Building on Self Determined Theory, the purpose of this article is to examine the relationship among feedback environment, creative personality, goal self-concordance and creative performance. Hierarchical regression analysis of a sample of 162 supervisor-employee dyads from nine industry firms. The results indicate that supervisor feedback environment is positively related to creative performance, the relationship between the supervisor feedback environment and creative performance is mediated by goal self-concordance perfectly and moderated by creative personality significantly. The mediation effort of goal self-concordance is significantly influenced by creative personality. The implication of improving employees' creative performance is further discussed. The present study advances several perspectives of previous studies, echoes recent suggestions that organizations interested in stimulating employee creativity might profitably focus on developing work contexts that support it. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5320563','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5320563">Impact of the Supervisor Feedback Environment on Creative Performance: A Moderated Mediation Model</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Zhang, Jian; Gong, Zhenxing; Zhang, Shuangyu; Zhao, Yujia 2017-01-01 Studies on the relationship between feedback and creative performance have only focused on the feedback-self and have underestimated the value of the feedback environment. Building on Self Determined Theory, the purpose of this article is to examine the relationship among feedback environment, creative personality, goal self-concordance and creative performance. Hierarchical regression analysis of a sample of 162 supervisor–employee dyads from nine industry firms. The results indicate that supervisor feedback environment is positively related to creative performance, the relationship between the supervisor feedback environment and creative performance is mediated by goal self-concordance perfectly and moderated by creative personality significantly. The mediation effort of goal self-concordance is significantly influenced by creative personality. The implication of improving employees’ creative performance is further discussed. The present study advances several perspectives of previous studies, echoes recent suggestions that organizations interested in stimulating employee creativity might profitably focus on developing work contexts that support it. PMID:28275362 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26877074','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26877074">Stochasticity and bifurcations in a reduced model with interlinked positive and negative feedback loops of CREB1 and CREB2 stimulated by 5-HT.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Hao, Lijie; Yang, Zhuoqin; Bi, Yuanhong 2016-04-01 The cyclic AMP (cAMP)-response element-binding protein (CREB) family of transcription factors is crucial in regulating gene expression required for long-term memory (LTM) formation. Upon exposure of sensory neurons to the neurotransmitter serotonin (5-HT), CREB1 is activated via activation of the protein kinase A (PKA) intracellular signaling pathways, and CREB2 as a transcriptional repressor is relieved possibly via phosphorylation of CREB2 by mitogen-activated protein kinase (MAPK). Song et al. [18] proposed a minimal model with only interlinked positive and negative feedback loops of transcriptional regulation by the activator CREB1 and the repressor CREB2. Without considering feedbacks between the CREB proteins, Pettigrew et al. [8] developed a computational model characterizing complex dynamics of biochemical pathways downstream of 5-HT receptors. In this work, to describe more simply the biochemical pathways and gene regulation underlying 5-HT-induced LTM, we add the important extracellular sensitizing stimulus 5-HT as well as the product Ap-uch into the Song's minimal model. We also strive to examine dynamical properties of the gene regulatory network under the changing concentration of the stimulus, [5-HT], cooperating with the varying positive feedback strength in inducing a high state of CREB1 for the establishment of long-term memory. Different dynamics including monostability, bistability and multistability due to coexistence of stable steady states and oscillations is investigated by means of codimension-2 bifurcation analysis. At the different positive feedback strengths, comparative analysis of deterministic and stochastic dynamics reveals that codimension-1 bifurcation with respect to [5-HT] as the parameter can predict diverse stochastic behaviors resulted from the finite number of molecules, and the number of CREB1 molecules more and more preferentially resides near the high steady state with increasing [5-HT], which contributes to long </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24051765','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24051765">UTOPIAN: user-driven topic modeling based on interactive nonnegative matrix factorization.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Choo, Jaegul; Lee, Changhyun; Reddy, Chandan K; Park, Haesun 2013-12-01 Topic modeling has been widely used for analyzing text document collections. Recently, there have been significant advancements in various topic modeling techniques, particularly in the form of probabilistic graphical modeling. State-of-the-art techniques such as Latent Dirichlet Allocation (LDA) have been successfully applied in visual text analytics. However, most of the widely-used methods based on probabilistic modeling have drawbacks in terms of consistency from multiple runs and empirical convergence. Furthermore, due to the complicatedness in the formulation and the algorithm, LDA cannot easily incorporate various types of user feedback. To tackle this problem, we propose a reliable and flexible visual analytics system for topic modeling called UTOPIAN (User-driven Topic modeling based on Interactive Nonnegative Matrix Factorization). Centered around its semi-supervised formulation, UTOPIAN enables users to interact with the topic modeling method and steer the result in a user-driven manner. We demonstrate the capability of UTOPIAN via several usage scenarios with real-world document corpuses such as InfoVis/VAST paper data set and product review data sets. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/AD1011064','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/AD1011064">Gregarious Convection and Radiative Feedbacks in Idealized Worlds</a> <a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a> 2016-08-29 exist neither on the globe nor within the cloud model. Since mesoscales impose great computational costs on atmosphere models, as well as inconven...Atmospheric Science, University of Miami, Miami, Florida, USA Abstract What role does convection play in cloud feedbacks? What role does convective... cloud fields depends systematically on global temperature, then convective organization could be a climate system feedback. How reconcilable and how </li> <li> <a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20010037378','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20010037378">Inferring Instantaneous, Multivariate and Nonlinear Sensitivities for the Analysis of Feedback Processes in a Dynamical System: Lorenz Model Case Study</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Aires, Filipe; Rossow, William B.; Hansen, James E. (Technical Monitor) 2001-01-01 A new approach is presented for the analysis of feedback processes in a nonlinear dynamical system by observing its variations. The new methodology consists of statistical estimates of the sensitivities between all pairs of variables in the system based on a neural network modeling of the dynamical system. The model can then be used to estimate the instantaneous, multivariate and nonlinear sensitivities, which are shown to be essential for the analysis of the feedbacks processes involved in the dynamical system. The method is described and tested on synthetic data from the low-order Lorenz circulation model where the correct sensitivities can be evaluated analytically. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/1422596-validation-statistical-methodology-extracting-vegetation-feedbacks-focus-north-african-ecosystems-community-earth-system-model','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/1422596-validation-statistical-methodology-extracting-vegetation-feedbacks-focus-north-african-ecosystems-community-earth-system-model">Validation of a Statistical Methodology for Extracting Vegetation Feedbacks: Focus on North African Ecosystems in the Community Earth System Model</a> <a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a> Yu, Yan; Notaro, Michael; Wang, Fuyao Generalized equilibrium feedback assessment (GEFA) is a potentially valuable multivariate statistical tool for extracting vegetation feedbacks to the atmosphere in either observations or coupled Earth system models. The reliability of GEFA at capturing the terrestrial impacts on regional climate is demonstrated in this paper using the National Center for Atmospheric Research Community Earth System Model (CESM), with focus on North Africa. The feedback is assessed statistically by applying GEFA to output from a fully coupled control run. To reduce the sampling error caused by short data records, the traditional or full GEFA is refined through stepwise GEFA by dropping unimportantmore » forcings. Two ensembles of dynamical experiments are developed for the Sahel or West African monsoon region against which GEFA-based vegetation feedbacks are evaluated. In these dynamical experiments, regional leaf area index (LAI) is modified either alone or in conjunction with soil moisture, with the latter runs motivated by strong regional soil moisture–LAI coupling. Stepwise GEFA boasts higher consistency between statistically and dynamically assessed atmospheric responses to land surface anomalies than full GEFA, especially with short data records. GEFA-based atmospheric responses are more consistent with the coupled soil moisture–LAI experiments, indicating that GEFA is assessing the combined impacts of coupled vegetation and soil moisture. Finally, both the statistical and dynamical assessments reveal a negative vegetation–rainfall feedback in the Sahel associated with an atmospheric stability mechanism in CESM versus a weaker positive feedback in the West African monsoon region associated with a moisture recycling mechanism in CESM.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1422596-validation-statistical-methodology-extracting-vegetation-feedbacks-focus-north-african-ecosystems-community-earth-system-model','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1422596-validation-statistical-methodology-extracting-vegetation-feedbacks-focus-north-african-ecosystems-community-earth-system-model">Validation of a Statistical Methodology for Extracting Vegetation Feedbacks: Focus on North African Ecosystems in the Community Earth System Model</a> <a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a> Yu, Yan; Notaro, Michael; Wang, Fuyao; ... 2018-02-05 Generalized equilibrium feedback assessment (GEFA) is a potentially valuable multivariate statistical tool for extracting vegetation feedbacks to the atmosphere in either observations or coupled Earth system models. The reliability of GEFA at capturing the terrestrial impacts on regional climate is demonstrated in this paper using the National Center for Atmospheric Research Community Earth System Model (CESM), with focus on North Africa. The feedback is assessed statistically by applying GEFA to output from a fully coupled control run. To reduce the sampling error caused by short data records, the traditional or full GEFA is refined through stepwise GEFA by dropping unimportantmore » forcings. Two ensembles of dynamical experiments are developed for the Sahel or West African monsoon region against which GEFA-based vegetation feedbacks are evaluated. In these dynamical experiments, regional leaf area index (LAI) is modified either alone or in conjunction with soil moisture, with the latter runs motivated by strong regional soil moisture–LAI coupling. Stepwise GEFA boasts higher consistency between statistically and dynamically assessed atmospheric responses to land surface anomalies than full GEFA, especially with short data records. GEFA-based atmospheric responses are more consistent with the coupled soil moisture–LAI experiments, indicating that GEFA is assessing the combined impacts of coupled vegetation and soil moisture. Finally, both the statistical and dynamical assessments reveal a negative vegetation–rainfall feedback in the Sahel associated with an atmospheric stability mechanism in CESM versus a weaker positive feedback in the West African monsoon region associated with a moisture recycling mechanism in CESM.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28507527','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28507527">Perceived Insider Status and Feedback Reactions: A Dual Path of Feedback Motivation Attribution.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Chen, Xiao; Liao, JianQiao; Wu, Weijiong; Zhang, Wei 2017-01-01 Many studies have evaluated how the characteristics of feedback receiver, feedback deliverer and feedback information influence psychological feedback reactions of the feedback receiver while largely neglecting that feedback intervention is a kind of social interaction process. To address this issue, this study proposes that employees' perceived insider status (PIS), as a kind of employee-organization relationship, could also influence employees' reactions to supervisory feedback. In particular, this study investigates the influence of PIS focusing on affective and cognitive feedback reactions, namely feedback satisfaction and feedback utility. Surveys were conducted in a machinery manufacturing company in the Guangdong province of China. Samples were collected from 192 employees. Data analysis demonstrated that PIS and feedback utility possessed a U-shaped relationship, whereas PIS and feedback satisfaction exhibited positively linear relationships. The analysis identified two kinds of mediating mechanisms related to feedback satisfaction and feedback utility. Internal feedback motivation attribution partially mediated the relationship between PIS and feedback satisfaction but failed to do the same with respect to the relationship between PIS and feedback utility. In contrast, external feedback motivation attribution partially mediated the relationship between PIS and feedback utility while failing to mediate the relationship between PIS and feedback satisfaction. Theoretical contributions and practical implications of the findings are discussed at the end of the paper. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20130009387','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20130009387">Feedback Augmented Sub-Ranging (FASR) Quantizer</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Guilligan, Gerard 2012-01-01 This innovation is intended to reduce the size, power, and complexity of pipeline analog-to-digital converters (ADCs) that require high resolution and speed along with low power. Digitizers are important components in any application where analog signals (such as light, sound, temperature, etc.) need to be digitally processed. The innovation implements amplification of a sampled residual voltage in a switched capacitor amplifier stage that does not depend on charge redistribution. The result is less sensitive to capacitor mismatches that cause gain errors, which are the main limitation of such amplifiers in pipeline ADCs. The residual errors due to mismatch are reduced by at least a factor of 16, which is equivalent to at least 4 bits of improvement. The settling time is also faster because of a higher feedback factor. In traditional switched capacitor residue amplifiers, closed-loop amplification of a sampled and held residue signal is achieved by redistributing sampled charge onto a feedback capacitor around a high-gain transconductance amplifier. The residual charge that was sampled during the acquisition or sampling phase is stored on two or more capacitors, often equal in value or integral multiples of each other. During the hold or amplification phase, all of the charge is redistributed onto one capacitor in the feedback loop of the amplifier to produce an amplified voltage. The key error source is the non-ideal ratios of feedback and input capacitors caused by manufacturing tolerances, called mismatches. The mismatches cause non-ideal closed-loop gain, leading to higher differential non-linearity. Traditional solutions to the mismatch errors are to use larger capacitor values (than dictated by thermal noise requirements) and/or complex calibration schemes, both of which increase the die size and power dissipation. The key features of this innovation are (1) the elimination of the need for charge redistribution to achieve an accurate closed-loop gain of two </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27860200','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27860200">PReSaFe: A model of barriers and facilitators to patients providing feedback on experiences of safety.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> De Brún, Aoife; Heavey, Emily; Waring, Justin; Dawson, Pamela; Scott, Jason 2017-08-01 The importance of involving patients in reporting on safety is increasingly recognized. Whilst studies have identified barriers to clinician incident reporting, few have explored barriers and facilitators to patient reporting of safety experiences. This paper explores patient perspectives on providing feedback on safety experiences. Patients (n=28) were invited to take part in semi-structured interviews when given a survey about their experiences of safety following hospital discharge. Transcripts were thematically analysed using NVivo10. Patients were recruited from four hospitals in the UK. Three themes were identified as barriers and facilitators to patient involvement in providing feedback on their safety experiences. The first, cognitive-cultural, found that whilst safety was a priority for most, some felt the term was not relevant to them because safety was the "default" position, and/or because safety could not be disentangled from the overall experience of care. The structural-procedural theme indicated that reporting was facilitated when patients saw the process as straightforward, but that disinclination or perceived inability to provide feedback was a barrier. Finally, learning and change illustrated that perception of the impact of feedback could facilitate or inhibit reporting. When collecting patient feedback on experiences of safety, it is important to consider what may help or hinder this process, beyond the process alone. We present a staged model of prerequisite barriers and facilitators and hypothesize that each stage needs to be achieved for patients to provide feedback on safety experiences. Implications for collecting meaningful data on patients' safety experiences are considered. © 2016 The Authors. Health Expectations Published by John Wiley & Sons Ltd. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29056782','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29056782">The importance of mechano-electrical feedback and inertia in cardiac electromechanics.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Costabal, Francisco Sahli; Concha, Felipe A; Hurtado, Daniel E; Kuhl, Ellen 2017-06-15 In the past years, a number cardiac electromechanics models have been developed to better understand the excitation-contraction behavior of the heart. However, there is no agreement on whether inertial forces play a role in this system. In this study, we assess the influence of mass in electromechanical simulations, using a fully coupled finite element model. We include the effect of mechano-electrical feedback via stretch activated currents. We compare five different models: electrophysiology, electromechanics, electromechanics with mechano-electrical feedback, electromechanics with mass, and electromechanics with mass and mechano-electrical feedback. We simulate normal conduction to study conduction velocity and spiral waves to study fibrillation. During normal conduction, mass in conjunction with mechano-electrical feedback increased the conduction velocity by 8.12% in comparison to the plain electrophysiology case. During the generation of a spiral wave, mass and mechano-electrical feedback generated secondary wavefronts, which were not present in any other model. These secondary wavefronts were initiated in tensile stretch regions that induced electrical currents. We expect that this study will help the research community to better understand the importance of mechanoelectrical feedback and inertia in cardiac electromechanics. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28001442','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28001442">"It's Just Not the Culture": A Qualitative Study Exploring Residents' Perceptions of the Impact of Institutional Culture on Feedback.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Ramani, Subha; Post, Sarah E; Könings, Karen; Mann, Karen; Katz, Joel T; van der Vleuten, Cees 2017-01-01 Phenomenon: Competency-based medical education requires ongoing performance-based feedback for professional growth. In several studies, medical trainees report that the quality of faculty feedback is inadequate. Sociocultural barriers to feedback exchanges are further amplified in graduate and postgraduate medical education settings, where trainees serve as frontline providers of patient care. Factors that affect institutional feedback culture, enhance feedback seeking, acceptance, and bidirectional feedback warrant further exploration in these settings. Using a constructivist grounded theory approach, we sought to examine residents' perspectives on institutional factors that affect the quality of feedback, factors that influence receptivity to feedback, and quality and impact of faculty feedback. Four focus group discussions were conducted, with two investigators present at each. One facilitated the discussion, and the other observed the interactions and took field notes. We audiotaped and transcribed the discussions, and performed a thematic analysis. Measures to ensure rigor included thick descriptions, independent coding by two investigators, and attention to reflexivity. We identified five key themes, dominated by resident perceptions regarding the influence of institutional feedback culture. The theme labels are taken from direct participant quotes: (a) the cultural norm lacks clear expectations and messages around feedback, (b) the prevailing culture of niceness does not facilitate honest feedback, (c) bidirectional feedback is not part of the culture, (d) faculty-resident relationships impact credibility and receptivity to feedback, and (e) there is a need to establish a culture of longitudinal professional growth. Insights: Institutional culture could play a key role in influencing the quality, credibility, and acceptability of feedback. A polite culture promotes a positive learning environment but can be a barrier to honest feedback. Feedback initiatives </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018BGeo...15.1721M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018BGeo...15.1721M">Carbon-climate feedbacks accelerate ocean acidification</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Matear, Richard J.; Lenton, Andrew 2018-03-01 Carbon-climate feedbacks have the potential to significantly impact the future climate by altering atmospheric CO2 concentrations (Zaehle et al. 2010). By modifying the future atmospheric CO2 concentrations, the carbon-climate feedbacks will also influence the future ocean acidification trajectory. Here, we use the CO2 emissions scenarios from four representative concentration pathways (RCPs) with an Earth system model to project the future trajectories of ocean acidification with the inclusion of carbon-climate feedbacks. We show that simulated carbon-climate feedbacks can significantly impact the onset of undersaturated aragonite conditions in the Southern and Arctic oceans, the suitable habitat for tropical coral and the deepwater saturation states. Under the high-emissions scenarios (RCP8.5 and RCP6), the carbon-climate feedbacks advance the onset of surface water under saturation and the decline in suitable coral reef habitat by a decade or more. The impacts of the carbon-climate feedbacks are most significant for the medium- (RCP4.5) and low-emissions (RCP2.6) scenarios. For the RCP4.5 scenario, by 2100 the carbon-climate feedbacks nearly double the area of surface water undersaturated with respect to aragonite and reduce by 50 % the surface water suitable for coral reefs. For the RCP2.6 scenario, by 2100 the carbon-climate feedbacks reduce the area suitable for coral reefs by 40 % and increase the area of undersaturated surface water by 20 %. The sensitivity of ocean acidification to the carbon-climate feedbacks in the low to medium emission scenarios is important because recent CO2 emission reduction commitments are trying to transition emissions to such a scenario. Our study highlights the need to better characterise the carbon-climate feedbacks and ensure we do not underestimate the projected ocean acidification. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5410612','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5410612">Perceived Insider Status and Feedback Reactions: A Dual Path of Feedback Motivation Attribution</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Chen, Xiao; Liao, JianQiao; Wu, Weijiong; Zhang, Wei 2017-01-01 Many studies have evaluated how the characteristics of feedback receiver, feedback deliverer and feedback information influence psychological feedback reactions of the feedback receiver while largely neglecting that feedback intervention is a kind of social interaction process. To address this issue, this study proposes that employees’ perceived insider status (PIS), as a kind of employee-organization relationship, could also influence employees’ reactions to supervisory feedback. In particular, this study investigates the influence of PIS focusing on affective and cognitive feedback reactions, namely feedback satisfaction and feedback utility. Surveys were conducted in a machinery manufacturing company in the Guangdong province of China. Samples were collected from 192 employees. Data analysis demonstrated that PIS and feedback utility possessed a U-shaped relationship, whereas PIS and feedback satisfaction exhibited positively linear relationships. The analysis identified two kinds of mediating mechanisms related to feedback satisfaction and feedback utility. Internal feedback motivation attribution partially mediated the relationship between PIS and feedback satisfaction but failed to do the same with respect to the relationship between PIS and feedback utility. In contrast, external feedback motivation attribution partially mediated the relationship between PIS and feedback utility while failing to mediate the relationship between PIS and feedback satisfaction. Theoretical contributions and practical implications of the findings are discussed at the end of the paper. PMID:28507527 </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ESD.....9..413A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ESD.....9..413A">Earth system model simulations show different feedback strengths of the terrestrial carbon cycle under glacial and interglacial conditions</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Adloff, Markus; Reick, Christian H.; Claussen, Martin 2018-04-01 In simulations with the MPI Earth System Model, we study the feedback between the terrestrial carbon cycle and atmospheric CO2 concentrations under ice age and interglacial conditions. We find different sensitivities of terrestrial carbon storage to rising CO2 concentrations in the two settings. This result is obtained by comparing the transient response of the terrestrial carbon cycle to a fast and strong atmospheric CO2 concentration increase (roughly 900 ppm) in Coupled Climate Carbon Cycle Model Intercomparison Project (C4MIP)-type simulations starting from climates representing the Last Glacial Maximum (LGM) and pre-industrial times (PI). In this set-up we disentangle terrestrial contributions to the feedback from the carbon-concentration effect, acting biogeochemically via enhanced photosynthetic productivity when CO2 concentrations increase, and the carbon-climate effect, which affects the carbon cycle via greenhouse warming. We find that the carbon-concentration effect is larger under LGM than PI conditions because photosynthetic productivity is more sensitive when starting from the lower, glacial CO2 concentration and CO2 fertilization saturates later. This leads to a larger productivity increase in the LGM experiment. Concerning the carbon-climate effect, it is the PI experiment in which land carbon responds more sensitively to the warming under rising CO2 because at the already initially higher temperatures, tropical plant productivity deteriorates more strongly and extratropical carbon is respired more effectively. Consequently, land carbon losses increase faster in the PI than in the LGM case. Separating the carbon-climate and carbon-concentration effects, we find that they are almost additive for our model set-up; i.e. their synergy is small in the global sum of carbon changes. Together, the two effects result in an overall strength of the terrestrial carbon cycle feedback that is almost twice as large in the LGM experiment as in the PI experiment </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016SPIE10030E..16R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016SPIE10030E..16R">Optical feedback effects on terahertz quantum cascade lasers: modelling and applications</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Rakić, Aleksandar D.; Lim, Yah Leng; Taimre, Thomas; Agnew, Gary; Qi, Xiaoqiong; Bertling, Karl; Han, She; Wilson, Stephen J.; Kundu, Iman; Grier, Andrew; Ikonić, Zoran; Valavanis, Alexander; Demić, Aleksandar; Keeley, James; Li, Lianhe H.; Linfield, Edmund H.; Davies, A. Giles; Harrison, Paul; Ferguson, Blake; Walker, Graeme; Prow, Tarl; Indjin, Dragan; Soyer, H. Peter 2016-11-01 Terahertz (THz) quantum cascade lasers (QCLs) are compact sources of radiation in the 1-5 THz range with significant potential for applications in sensing and imaging. Laser feedback interferometry (LFI) with THz QCLs is a technique utilizing the sensitivity of the QCL to the radiation reflected back into the laser cavity from an external target. We will discuss modelling techniques and explore the applications of LFI in biological tissue imaging and will show that the confocal nature of the QCL in LFI systems, with their innate capacity for depth sectioning, makes them suitable for skin diagnostics with the well-known advantages of more conventional confocal microscopes. A demonstration of discrimination of neoplasia from healthy tissue using a THz, LFI-based system in the context of melanoma is presented using a transgenic mouse model. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22521781-star-cluster-formation-stellar-feedback-large-scale-inflow','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22521781-star-cluster-formation-stellar-feedback-large-scale-inflow">STAR CLUSTER FORMATION WITH STELLAR FEEDBACK AND LARGE-SCALE INFLOW</a> <a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a> Matzner, Christopher D.; Jumper, Peter H., E-mail: matzner@astro.utoronto.ca 2015-12-10 During star cluster formation, ongoing mass accretion is resisted by stellar feedback in the form of protostellar outflows from the low-mass stars and photo-ionization and radiation pressure feedback from the massive stars. We model the evolution of cluster-forming regions during a phase in which both accretion and feedback are present and use these models to investigate how star cluster formation might terminate. Protostellar outflows are the strongest form of feedback in low-mass regions, but these cannot stop cluster formation if matter continues to flow in. In more massive clusters, radiation pressure and photo-ionization rapidly clear the cluster-forming gas when itsmore » column density is too small. We assess the rates of dynamical mass ejection and of evaporation, while accounting for the important effect of dust opacity on photo-ionization. Our models are consistent with the census of protostellar outflows in NGC 1333 and Serpens South and with the dust temperatures observed in regions of massive star formation. Comparing observations of massive cluster-forming regions against our model parameter space, and against our expectations for accretion-driven evolution, we infer that massive-star feedback is a likely cause of gas disruption in regions with velocity dispersions less than a few kilometers per second, but that more massive and more turbulent regions are too strongly bound for stellar feedback to be disruptive.« less </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active">18</li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active">19</li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3995711','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3995711">Acute Stress Modulates Feedback Processing in Men and Women: Differential Effects on the Feedback-Related Negativity and Theta and Beta Power</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Banis, Stella; Geerligs, Linda; Lorist, Monicque M. 2014-01-01 Sex-specific prevalence rates in mental and physical disorders may be partly explained by sex differences in physiological stress responses. Neural networks that might be involved are those underlying feedback processing. Aim of the present EEG study was to investigate whether acute stress alters feedback processing, and whether stress effects differ between men and women. Male and female participants performed a gambling task, in a control and a stress condition. Stress was induced by exposing participants to a noise stressor. Brain activity was analyzed using both event-related potential and time-frequency analyses, measuring the feedback-related negativity (FRN) and feedback-related changes in theta and beta oscillatory power, respectively. While the FRN and feedback-related theta power were similarly affected by stress induction in both sexes, feedback-related beta power depended on the combination of stress induction condition and sex. FRN amplitude and theta power increases were smaller in the stress relative to the control condition in both sexes, demonstrating that acute noise stress impairs performance monitoring irrespective of sex. However, in the stress but not in the control condition, early lower beta-band power increases were larger for men than women, indicating that stress effects on feedback processing are partly sex-dependent. Our findings suggest that sex-specific effects on feedback processing may comprise a factor underlying sex-specific stress responses. PMID:24755943 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11675340','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11675340">Negative feedback on the effects of stem cell factor on hematopoiesis is partly mediated through neutral endopeptidase activity on substance P: a combined functional and proteomic study.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Joshi, D D; Dang, A; Yadav, P; Qian, J; Bandari, P S; Chen, K; Donnelly, R; Castro, T; Gascon, P; Haider, A; Rameshwar, P 2001-11-01 Hematopoietic regulation is a complex but dynamic process regulated by intercellular and intracellular interactions within the bone marrow (BM) microenvironment. Through neurokinin-1 (NK-1) and NK-2 receptors, peptides (eg, substance P [SP]) encoded by the preprotachykinin-I gene mediate distinct hematopoietic effects. Cytokines, associated with hematopoietic stimulation, and SP regulate the expression of each other in BM mesenchymal and immune cells. Neutral endopeptidase (NEP) uses SP as a substrate to produce SP(1-4), which inhibits the proliferation of matured myeloid progenitor. This study determines whether the degradation of SP to SP(1-4) by endogenous NEP in BM stroma could be a feedback on hematopoietic stimulation by stem cell factor (SCF). SP(1-4) induced the production of transforming growth factor (TGF)-beta and tumor necrosis factor-alpha in BM stroma. TGF-beta production accounted for part of the inhibitory effects by SP(1-4) on the proliferation of early (granulocyte-macrophage colony-forming units) and late (long-term culture-initiating cells) hematopoietic progenitors. Enzyme-linked immunosorbent assays and/or protein-chip arrays indicated a timeline change of SP to SP(1-4) in BM stroma stimulated with SCF, which correlated with increase in NEP messenger RNA. Since SP and its fragment, SP(1-4), interact with the same receptor to mediate opposing hematopoietic effects, 2 interactive studies were done to understand the dual responses of NK-1: (1) a 3-dimensional molecular model of NK-1 and SP and (2) screening of a random dodecapeptide library for SP(1-4) interacting sites. The effects of SP(1-4) on hematopoietic progenitors and the timeline change of SP to SP(1-4), together with the 3-dimensional model, provide a partial explanation for the feedback on the stimulatory effects of SCF and SP on hematopoiesis. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.C42A..06E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.C42A..06E">Quantifying Uncertainty in the Greenland Surface Mass Balance Elevation Feedback</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Edwards, T. 2015-12-01 As the shape of the Greenland ice sheet responds to changes in surface mass balance (SMB) and dynamics, it affects the surface mass balance through the atmospheric lapse rate and by altering atmospheric circulation patterns. Positive degree day models include simplified representations of this feedback, but it is difficult to simulate with state-of-the-art models because it requires coupling of regional climate models with dynamical ice sheet models, which is technically challenging. This difficulty, along with the high computational expense of regional climate models, also drastically limits opportunities for exploring the impact of modelling uncertainties on sea level projections. We present a parameterisation of the SMB-elevation feedback in the MAR regional climate model that provides a far easier and quicker estimate than atmosphere-ice sheet model coupling, which can be used with any ice sheet model. This allows us to use ensembles of different parameter values and ice sheet models to assess the effect of uncertainty in the feedback and ice sheet model structure on future sea level projections. We take a Bayesian approach to uncertainty in the feedback parameterisation, scoring the results from multiple possible "SMB lapse rates" according to how well they reproduce a MAR simulation with altered ice sheet topography. We test the impact of the resulting parameterisation on sea level projections using five ice sheet models forced by MAR (in turned forced by two different global climate models) under the emissions scenario A1B. The estimated additional sea level contribution due to the SMB-elevation feedback is 4.3% at 2100 (95% credibility interval 1.8-6.9%), and 9.6% at 2200 (3.6-16.0%). </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018GeoRL..45.5062S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018GeoRL..45.5062S">Ocean Carbon Cycle Feedbacks Under Negative Emissions</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Schwinger, Jörg; Tjiputra, Jerry 2018-05-01 Negative emissions will most likely be needed to achieve ambitious climate targets, such as limiting global warming to 1.5°. Here we analyze the ocean carbon-concentration and carbon-climate feedback in an Earth system model under an idealized strong CO2 peak and decline scenario. We find that the ocean carbon-climate feedback is not reversible by means of negative emissions on decadal to centennial timescales. When preindustrial surface climate is restored, the oceans, due to the carbon-climate feedback, still contain about 110 Pg less carbon compared to a simulation without climate change. This result is unsurprising but highlights an issue with a widely used carbon cycle feedback metric. We show that this metric can be greatly improved by using ocean potential temperature as a proxy for climate change. The nonlinearity (nonadditivity) of climate and CO2-driven feedbacks continues to grow after the atmospheric CO2 peak. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23334125','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23334125">Feedback and rewards, part II: formal and informal feedback reviews.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Harolds, Jay 2013-02-01 There are 2 major classes of feedback. One class of feedback consists of the informal, numerous conversations between various people in the organization regarding the performance, behavior, and goals of an individual. Another class of feedback consists of formal reviews held once or twice a year between a supervisor and an individual. This article discusses both types of feedback. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1430400','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1430400">Feedback equilibrium control during human standing</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Alexandrov, Alexei V.; AA, Frolov; FB, Horak; P, Carlson-Kuhta; S, Park 2006-01-01 Equilibrium maintenance during standing in humans was investigated with a 3-joint (ankle, knee and hip) sagittal model of body movement. The experimental paradigm consisted of sudden perturbations of humans in quiet stance by backward displacements of the support platform. Data analysis was performed using eigenvectors of motion equation. The results supported three conclusions. First, independent feedback control of movements along eigenvectors (eigenmovements) can adequately describe human postural responses to stance perturbations. This conclusion is consistent with previous observations (Alexandrov et al., 2001b) that these same eigenmovements are also independently controlled in a feed-forward manner during voluntary upper-trunk bending. Second, independent feedback control of each eigenmovement is sufficient to provide its stability. Third, the feedback loop in each eigenmovement can be modeled as a linear visco-elastic spring with delay. Visco-elastic parameters and time-delay values result from the combined contribution of passive visco-elastic mechanisms and sensory systems of different modalities. PMID:16228222 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25955788','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25955788">Impaired Inhibitory Force Feedback in Fixed Dystonia.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Mugge, Winfred; Schouten, Alfred C; van Hilten, Jacobus J; van der Helm, Frans C T 2016-04-01 Complex regional pain syndrome (CRPS) is a multifactorial disorder associated with an aberrant host response to tissue injury. About 25% of CRPS patients suffer poorly understood involuntary sustained muscle contractions associated with dysfunctional reflexes that result in abnormal postures (fixed dystonia). A recent modeling study simulated fixed dystonia (FD) caused by aberrant force feedback. The current study aims to validate this hypothesis by experimentally recording the modulation of reflexive force feedback in patients with FD. CRPS patients with and without FD, patients with FD but without CRPS, as well as healthy controls participated in the experiment. Three task instructions and three perturbation characteristics were used to evoke a wide range of responses to force perturbations. During position tasks ("maintain posture"), healthy subjects as well as patients resisted the perturbations, becoming more stiff than when being relaxed (i.e., the relax task). Healthy subjects and CRPS patients without FD were both more compliant during force tasks ("maintain force") than during relax tasks, meaning they actively gave way to the imposed forces. Remarkably, the patients with FD failed to do so. A neuromuscular model was fitted to the experimental data to separate the distinct contributions of position, velocity and force feedback, as well as co-contraction to the motor behavior. The neuromuscular modeling indicated that inhibitory force feedback is deregulated in patients with FD, for both CRPS and non-CRPS patients. From previously published simulation results and the present experimental study, it is concluded that aberrant force feedback plays a role in fixed dystonia. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/12261578','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/12261578">A system dynamics feedback control model study of population of "India 2001" and policies for stabilizing growth.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Patil, M K; Janahanlal, P S 1978-06-01 A mathematical population model is presented and diagrammed. The model is a nonlinear, higher order, self-regulating, goal-seeking system. In other words, the model treats the population system like a biological system which has positive and negative feedbacks. The model incorporates the effects of important economic factors that influence human birth and death rates. It calculates the total population size, which is a determinant of resource usage. It also indicates the demographic response, through a changing birth and death rate, to a changing resource supply. The model is illustrated with Indian population data, disaggregated by age into 15 levels each of which is, in turn, divided into 4 income levels. The effect on population growth of various alternative population policies is analyzed with the goal of stabilizing the population growth quickly without causing undue hardship. Different computer runs of the model are conducted, using different levels of family planning practice, different ages at marriage, and different distributions of income throughout the country. The policy which would result in the lowest population for the year 2001 is 1 in which family planning acceptance levels would increase from 15% in 1975 to 60% in 1980 and 100% from 1990 on. However, there is widespread opposition to this policy. It is felt that a much slower rise in family planning acceptance would be a more acceptable policy for stabilizing population in India. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.4710S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.4710S">Constructing wetlands: measuring and modeling feedbacks of oxidation processes between plants and clay-rich material</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Saaltink, Rémon; Dekker, Stefan C.; Griffioen, Jasper; Wassen, Martin J. 2016-04-01 Interest is growing in using soft sediment as a building material in eco-engineering projects. Wetland construction in the Dutch lake Markermeer is an example: here the option of dredging some of the clay-rich lake-bed sediment and using it to construct 10.000 ha of wetland will soon go under construction. Natural processes will be utilized during and after construction to accelerate ecosystem development. Knowing that plants can eco-engineer their environment via positive or negative biogeochemical plant-soil feedbacks, we conducted a six-month greenhouse experiment to identify the key biogeochemical processes in the mud when Phragmites australis is used as an eco-engineering species. We applied inverse biogeochemical modeling to link observed changes in pore water composition to biogeochemical processes. Two months after transplantation we observed reduced plant growth and shriveling as well as yellowing of foliage. The N:P ratios of plant tissue were low and were affected not by hampered uptake of N but by enhanced uptake of P. Plant analyses revealed high Fe concentrations in the leaves and roots. Sulfate concentrations rose drastically in our experiment due to pyrite oxidation; as reduction of sulfate will decouple Fe-P in reducing conditions, we argue that plant-induced iron toxicity hampered plant growth, forming a negative feedback loop, while simultaneously there was a positive feedback loop, as iron toxicity promotes P mobilization as a result of reduced conditions through root death, thereby stimulating plant growth and regeneration. Given these two feedback mechanisms, we propose that when building wetlands from these mud deposits Fe-tolerant species are used rather than species that thrive in N-limited conditions. The results presented in this study demonstrate the importance of studying the biogeochemical properties of the building material and the feedback mechanisms between plant and soil prior to finalizing the design of the eco-engineering project. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/EJ1167256.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/EJ1167256.pdf">Written Corrective Feedback: Student Preferences and Teacher Feedback Practices</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Irwin, Bradley 2017-01-01 This case study explores the intricate interaction between students' preferences for written corrective feedback and actual teacher feedback practices in a second year academic EFL writing class in a Japanese university. Specific institutional and instructional details establish the context in which written feedback is being provided. A… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19000212','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19000212">Feedback produces divergence from prospect theory in descriptive choice.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Jessup, Ryan K; Bishara, Anthony J; Busemeyer, Jerome R 2008-10-01 A recent study demonstrated that individuals making experience-based choices underweight small probabilities, in contrast to the overweighting observed in a typical descriptive paradigm. We tested whether trial-by-trial feedback in a repeated descriptive paradigm would engender choices more correspondent with experiential or descriptive paradigms. The results of a repeated gambling task indicated that individuals receiving feedback underweighted small probabilities, relative to their no-feedback counterparts. These results implicate feedback as a critical component during the decision-making process, even in the presence of fully specified descriptive information. A model comparison at the individual-subject level suggested that feedback drove individuals' decision weights toward objective probability weighting. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25263844','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25263844">The predictability of frequency-altered auditory feedback changes the weighting of feedback and feedforward input for speech motor control.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Scheerer, Nichole E; Jones, Jeffery A 2014-12-01 Speech production requires the combined effort of a feedback control system driven by sensory feedback, and a feedforward control system driven by internal models. However, the factors that dictate the relative weighting of these feedback and feedforward control systems are unclear. In this event-related potential (ERP) study, participants produced vocalisations while being exposed to blocks of frequency-altered feedback (FAF) perturbations that were either predictable in magnitude (consistently either 50 or 100 cents) or unpredictable in magnitude (50- and 100-cent perturbations varying randomly within each vocalisation). Vocal and P1-N1-P2 ERP responses revealed decreases in the magnitude and trial-to-trial variability of vocal responses, smaller N1 amplitudes, and shorter vocal, P1 and N1 response latencies following predictable FAF perturbation magnitudes. In addition, vocal response magnitudes correlated with N1 amplitudes, vocal response latencies, and P2 latencies. This pattern of results suggests that after repeated exposure to predictable FAF perturbations, the contribution of the feedforward control system increases. Examination of the presentation order of the FAF perturbations revealed smaller compensatory responses, smaller P1 and P2 amplitudes, and shorter N1 latencies when the block of predictable 100-cent perturbations occurred prior to the block of predictable 50-cent perturbations. These results suggest that exposure to large perturbations modulates responses to subsequent perturbations of equal or smaller size. Similarly, exposure to a 100-cent perturbation prior to a 50-cent perturbation within a vocalisation decreased the magnitude of vocal and N1 responses, but increased P1 and P2 latencies. Thus, exposure to a single perturbation can affect responses to subsequent perturbations. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940017168','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940017168">Climate forcings and feedbacks</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Hansen, James 1993-01-01 Global temperature has increased significantly during the past century. Understanding the causes of observed global temperature change is impossible in the absence of adequate monitoring of changes in global climate forcings and radiative feedbacks. Climate forcings are changes imposed on the planet's energy balance, such as change of incoming sunlight or a human-induced change of surface properties due to deforestation. Radiative feedbacks are radiative changes induced by climate change, such as alteration of cloud properties or the extent of sea ice. Monitoring of global climate forcings and feedbacks, if sufficiently precise and long-term, can provide a very strong constraint on interpretation of observed temperature change. Such monitoring is essential to eliminate uncertainties about the relative importance of various climate change mechanisms including tropospheric sulfate aerosols from burning of coal and oil smoke from slash and burn agriculture, changes of solar irradiance changes of several greenhouse gases, and many other mechanisms. The considerable variability of observed temperature, together with evidence that a substantial portion of this variability is unforced indicates that observations of climate forcings and feedbacks must be continued for decades. Since the climate system responds to the time integral of the forcing, a further requirement is that the observations be carried out continuously. However, precise observations of forcings and feedbacks will also be able to provide valuable conclusions on shorter time scales. For example, knowledge of the climate forcing by increasing CFC's relative to the forcing by changing ozone is important to policymakers, as is information on the forcing by CO2 relative to the forcing by sulfate aerosols. It will also be possible to obtain valuable tests of climate models on short time scales, if there is precise monitoring of all forcings and feedbacks during and after events such as a large volcanic eruption </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017NatSR...738244K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017NatSR...738244K">Relaxation oscillations and hierarchy of feedbacks in MAPK signaling</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Kochańczyk, Marek; Kocieniewski, Paweł; Kozłowska, Emilia; Jaruszewicz-Błońska, Joanna; Sparta, Breanne; Pargett, Michael; Albeck, John G.; Hlavacek, William S.; Lipniacki, Tomasz 2017-01-01 We formulated a computational model for a MAPK signaling cascade downstream of the EGF receptor to investigate how interlinked positive and negative feedback loops process EGF signals into ERK pulses of constant amplitude but dose-dependent duration and frequency. A positive feedback loop involving RAS and SOS, which leads to bistability and allows for switch-like responses to inputs, is nested within a negative feedback loop that encompasses RAS and RAF, MEK, and ERK that inhibits SOS via phosphorylation. This negative feedback, operating on a longer time scale, changes switch-like behavior into oscillations having a period of 1 hour or longer. Two auxiliary negative feedback loops, from ERK to MEK and RAF, placed downstream of the positive feedback, shape the temporal ERK activity profile but are dispensable for oscillations. Thus, the positive feedback introduces a hierarchy among negative feedback loops, such that the effect of a negative feedback depends on its position with respect to the positive feedback loop. Furthermore, a combination of the fast positive feedback involving slow-diffusing membrane components with slower negative feedbacks involving faster diffusing cytoplasmic components leads to local excitation/global inhibition dynamics, which allows the MAPK cascade to transmit paracrine EGF signals into spatially non-uniform ERK activity pulses. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=current+AND+feedback&id=EJ1120349','ERIC'); return false;" href="https://eric.ed.gov/?q=current+AND+feedback&id=EJ1120349">Feedback on Feedback Practice: Perceptions of Students and Academics</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Mulliner, Emma; Tucker, Matthew 2017-01-01 While feedback is widely considered central to student learning, students across the higher education sector commonly report dissatisfaction with the feedback they receive. In contrast, academics often feel they provide quality and informative feedback. This article explores and compares the perceptions of students and academics with regard to… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1424979-modeling-east-asian-dust-its-radiative-feedbacks-cam4-bam','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1424979-modeling-east-asian-dust-its-radiative-feedbacks-cam4-bam">Modeling East Asian Dust and Its Radiative Feedbacks in CAM4-BAM</a> <a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a> Xie, Xiaoning; Liu, Xiaodong; Che, Huizheng; ... 2018-01-18 East Asian dust and its radiative feedbacks are analyzed by the use of the fourth version of the Community Atmosphere Model (CAM4) with a bulk aerosol model parameterization (BAM) for the dust size distribution (CAM4-BAM). Two numerical experiments are conducted and intercompared: one with (Active) and one without (Passive) the radiative effects of dust aerosols. This CAM4-BAM captures the main spatial distribution of the dust aerosol optical depth (AOD) and the dust surface concentrations over East Asia, with positive correlations with the local observational data on annual and seasonal means. A comparative analysis of the Active and Passive experiments revealsmore » that consideration of the dust-radiation interaction can significantly reduce dust emissions, loading, transport, and dry and wet depositions over East Asia, which is opposite to the enhanced dust cycle over North Africa. Further analysis of the contrasting dust-radiation feedbacks between North Africa and East Asia shows that over North Africa, the dust radiative forcing significantly increases the surface temperature and 10-m wind speed, whereas it decreases the surface temperature and the surface wind speeds over East Asia. These contrasting radiative effects, in turn, result in distinct dust cycle changes over these two regions. Thus, mechanistic analysis reveals that the radiative contrasts between East Asia and North Africa are mainly due to the differences in their regional surface albedo, dust vertical distribution and size distribution.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/1424979-modeling-east-asian-dust-its-radiative-feedbacks-cam4-bam','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/1424979-modeling-east-asian-dust-its-radiative-feedbacks-cam4-bam">Modeling East Asian Dust and Its Radiative Feedbacks in CAM4-BAM</a> <a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a> Xie, Xiaoning; Liu, Xiaodong; Che, Huizheng East Asian dust and its radiative feedbacks are analyzed by the use of the fourth version of the Community Atmosphere Model (CAM4) with a bulk aerosol model parameterization (BAM) for the dust size distribution (CAM4-BAM). Two numerical experiments are conducted and intercompared: one with (Active) and one without (Passive) the radiative effects of dust aerosols. This CAM4-BAM captures the main spatial distribution of the dust aerosol optical depth (AOD) and the dust surface concentrations over East Asia, with positive correlations with the local observational data on annual and seasonal means. A comparative analysis of the Active and Passive experiments revealsmore » that consideration of the dust-radiation interaction can significantly reduce dust emissions, loading, transport, and dry and wet depositions over East Asia, which is opposite to the enhanced dust cycle over North Africa. Further analysis of the contrasting dust-radiation feedbacks between North Africa and East Asia shows that over North Africa, the dust radiative forcing significantly increases the surface temperature and 10-m wind speed, whereas it decreases the surface temperature and the surface wind speeds over East Asia. These contrasting radiative effects, in turn, result in distinct dust cycle changes over these two regions. Thus, mechanistic analysis reveals that the radiative contrasts between East Asia and North Africa are mainly due to the differences in their regional surface albedo, dust vertical distribution and size distribution.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010APS..MARZ13007A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010APS..MARZ13007A">Towards random matrix model of breaking the time-reversal invariance of elastic waves in chaotic cavities by feedback</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Antoniuk, Oleg; Sprik, Rudolf 2010-03-01 We developed a random matrix model to describe the statistics of resonances in an acoustic cavity with broken time-reversal invariance. Time-reversal invariance braking is achieved by connecting an amplified feedback loop between two transducers on the surface of the cavity. The model is based on approach [1] that describes time- reversal properties of the cavity without a feedback loop. Statistics of eigenvalues (nearest neighbor resonance spacing distributions and spectral rigidity) has been calculated and compared to the statistics obtained from our experimental data. Experiments have been performed on aluminum block of chaotic shape confining ultrasound waves. [1] Carsten Draeger and Mathias Fink, One-channel time- reversal in chaotic cavities: Theoretical limits, Journal of Acoustical Society of America, vol. 105, Nr. 2, pp. 611-617 (1999) </li> <li> <a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/EJ1043247.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/EJ1043247.pdf">Using Confidence as Feedback in Multi-Sized Learning Environments</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Hench, Thomas L. 2014-01-01 This paper describes the use of existing confidence and performance data to provide feedback by first demonstrating the data's fit to a simple linear model. The paper continues by showing how the model's use as a benchmark provides feedback to allow current or future students to infer either the difficulty or the degree of under or over… </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017NucFu..57k6026S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017NucFu..57k6026S">Enhanced reproducibility of L-mode plasma discharges via physics-model-based q-profile feedback control in DIII-D</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Schuster, E.; Wehner, W. P.; Barton, J. E.; Boyer, M. D.; Luce, T. C.; Ferron, J. R.; Holcomb, C. T.; Walker, M. L.; Humphreys, D. A.; Solomon, W. M.; Penaflor, B. G.; Johnson, R. D. 2017-11-01 Recent experiments on DIII-D demonstrate the potential of physics-model-based q-profile control to improve reproducibility of plasma discharges. A combined feedforward + feedback control scheme is employed to optimize the current ramp-up phase by consistently achieving target q profiles (Target 1: q_min=1.3, q95=4.4 ; Target 2: q_min=1.65, q95=5.0 ; Target 3: q_min=2.1, q95=6.2 ) at prescribed times during the plasma formation phase (Target 1: t=1.5 s; Target 2: t=1.3 s; Target 3: t=1.0 s). At the core of the control scheme is a nonlinear, first-principles-driven, physics-based, control-oriented model of the plasma dynamics valid for low confinement (L-mode) scenarios. To prevent undesired L-H transitions, a constraint on the maximum allowable total auxiliary power is imposed in addition to the maximum powers for the individual heating and current-drive sources. Experimental results are presented to demonstrate the effectiveness of the combined feedforward + feedback control scheme to consistently achieve the desired target profiles at the predefined times. These results also show how the addition of feedback control significantly improves upon the feedforward-only control solution by reducing the matching error and also how the feedback controller is able to reduce the matching error as the constraint on the maximum allowable total auxiliary power is relaxed while keeping the plasma in L-mode. </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active">19</li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active">20</li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMGC21B1094F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMGC21B1094F">Validation of snow characteristics and snow albedo feedback in the Canadian Regional Climate Model simulations over North America</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Fang, B.; Sushama, L.; Diro, G. T. 2015-12-01 Snow characteristics and snow albedo feedback (SAF) over North America, as simulated by the fifth-generation Canadian Regional Climate Model (CRCM5), when driven by ERA-40/ERA-Interim, CanESM2 and MPI-ESM-LR at the lateral boundaries, are analyzed in this study. Validation of snow characteristics is performed by comparing simulations against available observations from MODIS, ISCCP and CMC. Results show that the model is able to represent the main spatial distribution of snow characteristics with some overestimation in snow mass and snow depth over the Canadian high Arctic. Some overestimation in surface albedo is also noted for the boreal region which is believed to be related to the snow unloading parameterization, as well as the overestimation of snow albedo. SAF is assessed both in seasonal and climate change contexts when possible. The strength of SAF is quantified as the amount of additional net shortwave radiation at the top of the atmosphere as surface albedo decreases in association with a 1°C increase in surface temperature. Following Qu and Hall (2007), this is expressed as the product of the variation in planetary albedo with surface albedo and the change in surface albedo for 1°C change in surface air temperature during the season, which in turn is determined by the strength of the snow cover and snowpack metamorphosis feedback loops. Analysis of the latter term in the seasonal cycle suggests that for CRCM5 simulations, the snow cover feedback loop is more dominant compared to the snowpack metamorphosis feedback loop, whereas for MODIS, the two feedback loops have more or less similar strength. Moreover, the SAF strength in the climate change context appears to be weaker than in the seasonal cycle and is sensitive to the driving GCM and the RCP scenario. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PhRvL.109o3602K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PhRvL.109o3602K">Superconducting Microwave Multivibrator Produced by Coherent Feedback</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Kerckhoff, Joseph; Lehnert, K. W. 2012-10-01 We investigate a nonlinear coherent feedback circuit constructed from preexisting superconducting microwave devices. The network exhibits emergent bistable and astable states, and we demonstrate its operation as a latch and the frequency locking of its oscillations. While the network is tedious to model by hand, our observations agree quite well with the semiclassical dynamical model produced by a new software package (N. Tezak , arXiv:1111.3081v1 [Phil. Trans. R. Soc. A (to be published)]) that systematically interpreted an idealized schematic of the system as a quantum optic feedback network. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NPGD....2..475S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NPGD....2..475S">Nonlinear feedback in a six-dimensional Lorenz Model: impact of an additional heating term</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Shen, B.-W. 2015-03-01 In this study, a six-dimensional Lorenz model (6DLM) is derived, based on a recent study using a five-dimensional (5-D) Lorenz model (LM), in order to examine the impact of an additional mode and its accompanying heating term on solution stability. The new mode added to improve the representation of the steamfunction is referred to as a secondary streamfunction mode, while the two additional modes, that appear in both the 6DLM and 5DLM but not in the original LM, are referred to as secondary temperature modes. Two energy conservation relationships of the 6DLM are first derived in the dissipationless limit. The impact of three additional modes on solution stability is examined by comparing numerical solutions and ensemble Lyapunov exponents of the 6DLM and 5DLM as well as the original LM. For the onset of chaos, the critical value of the normalized Rayleigh number (rc) is determined to be 41.1. The critical value is larger than that in the 3DLM (rc ~ 24.74), but slightly smaller than the one in the 5DLM (rc ~ 42.9). A stability analysis and numerical experiments obtained using generalized LMs, with or without simplifications, suggest the following: (1) negative nonlinear feedback in association with the secondary temperature modes, as first identified using the 5DLM, plays a dominant role in providing feedback for improving the solution's stability of the 6DLM, (2) the additional heating term in association with the secondary streamfunction mode may destabilize the solution, and (3) overall feedback due to the secondary streamfunction mode is much smaller than the feedback due to the secondary temperature modes; therefore, the critical Rayleigh number of the 6DLM is comparable to that of the 5DLM. The 5DLM and 6DLM collectively suggest different roles for small-scale processes (i.e., stabilization vs. destabilization), consistent with the following statement by Lorenz (1972): If the flap of a butterfly's wings can be instrumental in generating a tornado, it can </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NPGeo..22..749S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NPGeo..22..749S">Nonlinear feedback in a six-dimensional Lorenz model: impact of an additional heating term</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Shen, B.-W. 2015-12-01 In this study, a six-dimensional Lorenz model (6DLM) is derived, based on a recent study using a five-dimensional (5-D) Lorenz model (LM), in order to examine the impact of an additional mode and its accompanying heating term on solution stability. The new mode added to improve the representation of the streamfunction is referred to as a secondary streamfunction mode, while the two additional modes, which appear in both the 6DLM and 5DLM but not in the original LM, are referred to as secondary temperature modes. Two energy conservation relationships of the 6DLM are first derived in the dissipationless limit. The impact of three additional modes on solution stability is examined by comparing numerical solutions and ensemble Lyapunov exponents of the 6DLM and 5DLM as well as the original LM. For the onset of chaos, the critical value of the normalized Rayleigh number (rc) is determined to be 41.1. The critical value is larger than that in the 3DLM (rc ~ 24.74), but slightly smaller than the one in the 5DLM (rc ~ 42.9). A stability analysis and numerical experiments obtained using generalized LMs, with or without simplifications, suggest the following: (1) negative nonlinear feedback in association with the secondary temperature modes, as first identified using the 5DLM, plays a dominant role in providing feedback for improving the solution's stability of the 6DLM, (2) the additional heating term in association with the secondary streamfunction mode may destabilize the solution, and (3) overall feedback due to the secondary streamfunction mode is much smaller than the feedback due to the secondary temperature modes; therefore, the critical Rayleigh number of the 6DLM is comparable to that of the 5DLM. The 5DLM and 6DLM collectively suggest different roles for small-scale processes (i.e., stabilization vs. destabilization), consistent with the following statement by Lorenz (1972): "If the flap of a butterfly's wings can be instrumental in generating a tornado, it can </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5227098','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5227098">Rapid control and feedback rates enhance neuroprosthetic control</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Shanechi, Maryam M.; Orsborn, Amy L.; Moorman, Helene G.; Gowda, Suraj; Dangi, Siddharth; Carmena, Jose M. 2017-01-01 Brain-machine interfaces (BMI) create novel sensorimotor pathways for action. Much as the sensorimotor apparatus shapes natural motor control, the BMI pathway characteristics may also influence neuroprosthetic control. Here, we explore the influence of control and feedback rates, where control rate indicates how often motor commands are sent from the brain to the prosthetic, and feedback rate indicates how often visual feedback of the prosthetic is provided to the subject. We developed a new BMI that allows arbitrarily fast control and feedback rates, and used it to dissociate the effects of each rate in two monkeys. Increasing the control rate significantly improved control even when feedback rate was unchanged. Increasing the feedback rate further facilitated control. We also show that our high-rate BMI significantly outperformed state-of-the-art methods due to higher control and feedback rates, combined with a different point process mathematical encoding model. Our BMI paradigm can dissect the contribution of different elements in the sensorimotor pathway, providing a unique tool for studying neuroprosthetic control mechanisms. PMID:28059065 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28082010','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28082010">Perioperative feedback in surgical training: A systematic review.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> McKendy, Katherine M; Watanabe, Yusuke; Lee, Lawrence; Bilgic, Elif; Enani, Ghada; Feldman, Liane S; Fried, Gerald M; Vassiliou, Melina C 2017-07-01 Changes in surgical training have raised concerns about residents' operative exposure and preparedness for independent practice. One way of addressing this concern is by optimizing teaching and feedback in the operating room (OR). The objective of this study was to perform a systematic review on perioperative teaching and feedback. A systematic literature search identified articles from 1994 to 2014 that addressed teaching, feedback, guidance, or debriefing in the perioperative period. Data was extracted according to ENTREQ guidelines, and a qualitative analysis was performed. Thematic analysis of the 26 included studies identified four major topics. Observation of teaching behaviors in the OR described current teaching practices. Identification of effective teaching strategies analyzed teaching behaviors, differentiating positive and negative teaching strategies. Perceptions of teaching behaviors described resident and attending satisfaction with teaching in the OR. Finally models for delivering structured feedback cited examples of feedback strategies and measured their effectiveness. This study provides an overview of perioperative teaching and feedback for surgical trainees and identifies a need for improved quality and quantity of structured feedback. Copyright © 2016 Elsevier Inc. All rights reserved. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017NatCo...813825S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017NatCo...813825S">Rapid control and feedback rates enhance neuroprosthetic control</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Shanechi, Maryam M.; Orsborn, Amy L.; Moorman, Helene G.; Gowda, Suraj; Dangi, Siddharth; Carmena, Jose M. 2017-01-01 Brain-machine interfaces (BMI) create novel sensorimotor pathways for action. Much as the sensorimotor apparatus shapes natural motor control, the BMI pathway characteristics may also influence neuroprosthetic control. Here, we explore the influence of control and feedback rates, where control rate indicates how often motor commands are sent from the brain to the prosthetic, and feedback rate indicates how often visual feedback of the prosthetic is provided to the subject. We developed a new BMI that allows arbitrarily fast control and feedback rates, and used it to dissociate the effects of each rate in two monkeys. Increasing the control rate significantly improved control even when feedback rate was unchanged. Increasing the feedback rate further facilitated control. We also show that our high-rate BMI significantly outperformed state-of-the-art methods due to higher control and feedback rates, combined with a different point process mathematical encoding model. Our BMI paradigm can dissect the contribution of different elements in the sensorimotor pathway, providing a unique tool for studying neuroprosthetic control mechanisms. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4821804','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4821804">Mesolimbic confidence signals guide perceptual learning in the absence of external feedback</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Guggenmos, Matthias; Wilbertz, Gregor; Hebart, Martin N; Sterzer, Philipp 2016-01-01 It is well established that learning can occur without external feedback, yet normative reinforcement learning theories have difficulties explaining such instances of learning. Here, we propose that human observers are capable of generating their own feedback signals by monitoring internal decision variables. We investigated this hypothesis in a visual perceptual learning task using fMRI and confidence reports as a measure for this monitoring process. Employing a novel computational model in which learning is guided by confidence-based reinforcement signals, we found that mesolimbic brain areas encoded both anticipation and prediction error of confidence—in remarkable similarity to previous findings for external reward-based feedback. We demonstrate that the model accounts for choice and confidence reports and show that the mesolimbic confidence prediction error modulation derived through the model predicts individual learning success. These results provide a mechanistic neurobiological explanation for learning without external feedback by augmenting reinforcement models with confidence-based feedback. DOI: http://dx.doi.org/10.7554/eLife.13388.001 PMID:27021283 </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017Chaos..27k4306S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017Chaos..27k4306S">Quantization improves stabilization of dynamical systems with delayed feedback</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Stepan, Gabor; Milton, John G.; Insperger, Tamas 2017-11-01 We show that an unstable scalar dynamical system with time-delayed feedback can be stabilized by quantizing the feedback. The discrete time model corresponds to a previously unrecognized case of the microchaotic map in which the fixed point is both locally and globally repelling. In the continuous-time model, stabilization by quantization is possible when the fixed point in the absence of feedback is an unstable node, and in the presence of feedback, it is an unstable focus (spiral). The results are illustrated with numerical simulation of the unstable Hayes equation. The solutions of the quantized Hayes equation take the form of oscillations in which the amplitude is a function of the size of the quantization step. If the quantization step is sufficiently small, the amplitude of the oscillations can be small enough to practically approximate the dynamics around a stable fixed point. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.A14F..05S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.A14F..05S">Convection and the Soil-Moisture Precipitation Feedback</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Schar, C.; Froidevaux, P.; Keller, M.; Schlemmer, L.; Langhans, W.; Schmidli, J. 2014-12-01 The soil moisture - precipitation (SMP) feedback is of key importance for climate and climate change. A positive SMP feedback tends to amplify the hydrological response to external forcings (and thereby fosters precipitation and drought extremes), while a negative SMP feedback tends to moderate the influence of external forcings (and thereby stabilizes the hydrological cycle). The sign of the SMP feedback is poorly constrained by the current literature. Theoretical, modeling and observational studies partly disagree, and have suggested both negative and positive feedback loops. Can wet soil anomalies indeed result in either an increase or a decrease of precipitation (positive or negative SMP feedback, respectively)? Here we investigate the local SMP feedback using real-case and idealized convection-resolving simulations. An idealized simulation strategy is developed, which is able to replicate both signs of the feedback loop, depending on the environmental parameters. The mechanism relies on horizontal soil moisture variations, which may develop and intensify spontaneously. The positive expression of the feedback is associated with the initiation of convection over dry soil patches, but the convective cells then propagate over wet patches, where they strengthen and preferentially precipitate. The negative feedback may occur when the wind profile is too weak to support the propagation of convective features from dry to wet areas. Precipitation is then generally weaker and falls preferentially over dry patches. The results highlight the role of the mid-tropospheric flow in determining the sign of the feedback. A key element of the positive feedback is the exploitation of both low convective inhibition (CIN) over dry patches (for the initiation of convection), and high CAPE over wet patches (for the generation of precipitation). The results of this study will also be discussed in relation to climate change scenarios that exhibit large biases in surface temperature and </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4087028','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4087028">Modeling of endoluminal and interstitial ultrasound hyperthermia and thermal ablation: applications to device design, feedback control, and treatment planning</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Prakash, Punit; Salgaonkar, Vasant A.; Diederich, Chris J. 2014-01-01 Endoluminal and catheter-based ultrasound applicators are currently under development and are in clinical use for minimally invasive hyperthermia and thermal ablation of various tissue targets. Computational models play a critical role in in device design and optimization, assessment of therapeutic feasibility and safety, devising treatment monitoring and feedback control strategies, and performing patient-specific treatment planning with this technology. The critical aspects of theoretical modeling, applied specifically to endoluminal and interstitial ultrasound thermotherapy, are reviewed. Principles and practical techniques for modeling acoustic energy deposition, bioheat transfer, thermal tissue damage, and dynamic changes in the physical and physiological state of tissue are reviewed. The integration of these models and applications of simulation techniques in identification of device design parameters, development of real time feedback-control platforms, assessing the quality and safety of treatment delivery strategies, and optimization of inverse treatment plans are presented. PMID:23738697 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21900076','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21900076">Stabilization of nonlinear systems using sampled-data output-feedback fuzzy controller based on polynomial-fuzzy-model-based control approach.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Lam, H K 2012-02-01 This paper investigates the stability of sampled-data output-feedback (SDOF) polynomial-fuzzy-model-based control systems. Representing the nonlinear plant using a polynomial fuzzy model, an SDOF fuzzy controller is proposed to perform the control process using the system output information. As only the system output is available for feedback compensation, it is more challenging for the controller design and system analysis compared to the full-state-feedback case. Furthermore, because of the sampling activity, the control signal is kept constant by the zero-order hold during the sampling period, which complicates the system dynamics and makes the stability analysis more difficult. In this paper, two cases of SDOF fuzzy controllers, which either share the same number of fuzzy rules or not, are considered. The system stability is investigated based on the Lyapunov stability theory using the sum-of-squares (SOS) approach. SOS-based stability conditions are obtained to guarantee the system stability and synthesize the SDOF fuzzy controller. Simulation examples are given to demonstrate the merits of the proposed SDOF fuzzy control approach. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015APS..DPPG12077I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015APS..DPPG12077I">Performance Assessment of Model-Based Optimal Feedforward and Feedback Current Profile Control in NSTX-U using the TRANSP Code</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Ilhan, Z.; Wehner, W. P.; Schuster, E.; Boyer, M. D.; Gates, D. A.; Gerhardt, S.; Menard, J. 2015-11-01 Active control of the toroidal current density profile is crucial to achieve and maintain high-performance, MHD-stable plasma operation in NSTX-U. A first-principles-driven, control-oriented model describing the temporal evolution of the current profile has been proposed earlier by combining the magnetic diffusion equation with empirical correlations obtained at NSTX-U for the electron density, electron temperature, and non-inductive current drives. A feedforward + feedback control scheme for the requlation of the current profile is constructed by embedding the proposed nonlinear, physics-based model into the control design process. Firstly, nonlinear optimization techniques are used to design feedforward actuator trajectories that steer the plasma to a desired operating state with the objective of supporting the traditional trial-and-error experimental process of advanced scenario planning. Secondly, a feedback control algorithm to track a desired current profile evolution is developed with the goal of adding robustness to the overall control scheme. The effectiveness of the combined feedforward + feedback control algorithm for current profile regulation is tested in predictive simulations carried out in TRANSP. Supported by PPPL. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017BGeo...14.3051B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017BGeo...14.3051B">Quantifying uncertainties of permafrost carbon-climate feedbacks</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Burke, Eleanor J.; Ekici, Altug; Huang, Ye; Chadburn, Sarah E.; Huntingford, Chris; Ciais, Philippe; Friedlingstein, Pierre; Peng, Shushi; Krinner, Gerhard 2017-06-01 The land surface models JULES (Joint UK Land Environment Simulator, two versions) and ORCHIDEE-MICT (Organizing Carbon and Hydrology in Dynamic Ecosystems), each with a revised representation of permafrost carbon, were coupled to the Integrated Model Of Global Effects of climatic aNomalies (IMOGEN) intermediate-complexity climate and ocean carbon uptake model. IMOGEN calculates atmospheric carbon dioxide (CO2) and local monthly surface climate for a given emission scenario with the land-atmosphere CO2 flux exchange from either JULES or ORCHIDEE-MICT. These simulations include feedbacks associated with permafrost carbon changes in a warming world. Both IMOGEN-JULES and IMOGEN-ORCHIDEE-MICT were forced by historical and three alternative future-CO2-emission scenarios. Those simulations were performed for different climate sensitivities and regional climate change patterns based on 22 different Earth system models (ESMs) used for CMIP3 (phase 3 of the Coupled Model Intercomparison Project), allowing us to explore climate uncertainties in the context of permafrost carbon-climate feedbacks. Three future emission scenarios consistent with three representative concentration pathways were used: RCP2.6, RCP4.5 and RCP8.5. Paired simulations with and without frozen carbon processes were required to quantify the impact of the permafrost carbon feedback on climate change. The additional warming from the permafrost carbon feedback is between 0.2 and 12 % of the change in the global mean temperature (ΔT) by the year 2100 and 0.5 and 17 % of ΔT by 2300, with these ranges reflecting differences in land surface models, climate models and emissions pathway. As a percentage of ΔT, the permafrost carbon feedback has a greater impact on the low-emissions scenario (RCP2.6) than on the higher-emissions scenarios, suggesting that permafrost carbon should be taken into account when evaluating scenarios of heavy mitigation and stabilization. Structural differences between the land </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25227174','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25227174">Effectiveness of patient feedback as an educational intervention to improve medical student consultation (PTA Feedback Study): study protocol for a randomized controlled trial.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Lai, Michelle Mei Yee; Roberts, Noel; Martin, Jenepher 2014-09-17 Oral feedback from clinical educators is the traditional teaching method for improving clinical consultation skills in medical students. New approaches are needed to enhance this teaching model. Multisource feedback is a commonly used assessment method for learning among practising clinicians, but this assessment has not been explored rigorously in medical student education. This study seeks to evaluate if additional feedback on patient satisfaction improves medical student performance. The Patient Teaching Associate (PTA) Feedback Study is a single site randomized controlled, double-blinded trial with two parallel groups.An after-hours general practitioner clinic in Victoria, Australia, is adapted as a teaching clinic during the day. Medical students from two universities in their first clinical year participate in six simulated clinical consultations with ambulatory patient volunteers living with chronic illness. Eligible students will be randomized in equal proportions to receive patient satisfaction score feedback with the usual multisource feedback and the usual multisource feedback alone as control. Block randomization will be performed. We will assess patient satisfaction and consultation performance outcomes at baseline and after one semester and will compare any change in mean scores at the last session from that at baseline. We will model data using regression analysis to determine any differences between intervention and control groups. Full ethical approval has been obtained for the study. This trial will comply with CONSORT guidelines and we will disseminate data at conferences and in peer-reviewed journals. This is the first proposed trial to determine whether consumer feedback enhances the use of multisource feedback in medical student education, and to assess the value of multisource feedback in teaching and learning about the management of ambulatory patients living with chronic conditions. Australian New Zealand Clinical Trials Registry (ANZCTR </li> <li> <a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/publication/?seqNo115=332729','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/publication/?seqNo115=332729">Plant-soil feedbacks and mycorrhizal type influence temperate forest population dynamics</a> <a target="_blank" href="https://www.ars.usda.gov/research/publications/find-a-publication/">USDA-ARS?s Scientific Manuscript database</a> Feedback with soil biota is a major driver of diversity within terrestrial plant communities. However, little is known about the factors regulating plant-soil feedback, which can vary from positive to negative among plant species. In a large-scale observational and experimental study involving 55 sp... </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=engine+AND+research&pg=7&id=EJ1153899','ERIC'); return false;" href="https://eric.ed.gov/?q=engine+AND+research&pg=7&id=EJ1153899">Investigating the Impact of Automated Feedback on Students' Scientific Argumentation</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Zhu, Mengxiao; Lee, Hee-Sun; Wang, Ting; Liu, Ou Lydia; Belur, Vinetha; Pallant, Amy 2017-01-01 This study investigates the role of automated scoring and feedback in supporting students' construction of written scientific arguments while learning about factors that affect climate change in the classroom. The automated scoring and feedback technology was integrated into an online module. Students' written scientific argumentation occurred… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5473947','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5473947">Using Feedback to Promote Physical Activity: The Role of the Feedback Sign</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Kramer, Jan-Niklas 2017-01-01 Background Providing feedback is a technique to promote health behavior that is emphasized by behavior change theories. However, these theories make contradicting predictions regarding the effect of the feedback sign—that is, whether the feedback signals success or failure. Thus, it is unclear whether positive or negative feedback leads to more favorable behavior change in a health behavior intervention. Objective The aim of this study was to examine the effect of the feedback sign in a health behavior change intervention. Methods Data from participants (N=1623) of a 6-month physical activity intervention was used. Participants received a feedback email at the beginning of each month. Feedback was either positive or negative depending on the participants’ physical activity in the previous month. In an exploratory analysis, change in monthly step count averages was used to evaluate the feedback effect. Results The feedback sign did not predict the change in monthly step count averages over the course of the intervention (b=−84.28, P=.28). Descriptive differences between positive and negative feedback can be explained by regression to the mean. Conclusions The feedback sign might not influence the effect of monthly feedback emails sent out to participants of a large-scale physical activity intervention. However, randomized studies are needed to further support this conclusion. Limitations as well as opportunities for future research are discussed. PMID:28576757 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1067333','DOE-PATENT-XML'); return false;" href="https://www.osti.gov/servlets/purl/1067333">Temperature feedback control for long-term carrier-envelope phase locking</a> <a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a> Chang, Zenghu [Manhattan, KS; Yun, Chenxia [Manhattan, KS; Chen, Shouyuan [Manhattan, KS; Wang, He [Manhattan, KS; Chini, Michael [Manhattan, KS 2012-07-24 A feedback control module for stabilizing a carrier-envelope phase of an output of a laser oscillator system comprises a first photodetector, a second photodetector, a phase stabilizer, an optical modulator, and a thermal control element. The first photodetector may generate a first feedback signal corresponding to a first portion of a laser beam from an oscillator. The second photodetector may generate a second feedback signal corresponding to a second portion of the laser beam filtered by a low-pass filter. The phase stabilizer may divide the frequency of the first feedback signal by a factor and generate an error signal corresponding to the difference between the frequency-divided first feedback signal and the second feedback signal. The optical modulator may modulate the laser beam within the oscillator corresponding to the error signal. The thermal control unit may change the temperature of the oscillator corresponding to a signal operable to control the optical modulator. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3487539','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3487539">Decorrelation of Neural-Network Activity by Inhibitory Feedback</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Einevoll, Gaute T.; Diesmann, Markus 2012-01-01 Correlations in spike-train ensembles can seriously impair the encoding of information by their spatio-temporal structure. An inevitable source of correlation in finite neural networks is common presynaptic input to pairs of neurons. Recent studies demonstrate that spike correlations in recurrent neural networks are considerably smaller than expected based on the amount of shared presynaptic input. Here, we explain this observation by means of a linear network model and simulations of networks of leaky integrate-and-fire neurons. We show that inhibitory feedback efficiently suppresses pairwise correlations and, hence, population-rate fluctuations, thereby assigning inhibitory neurons the new role of active decorrelation. We quantify this decorrelation by comparing the responses of the intact recurrent network (feedback system) and systems where the statistics of the feedback channel is perturbed (feedforward system). Manipulations of the feedback statistics can lead to a significant increase in the power and coherence of the population response. In particular, neglecting correlations within the ensemble of feedback channels or between the external stimulus and the feedback amplifies population-rate fluctuations by orders of magnitude. The fluctuation suppression in homogeneous inhibitory networks is explained by a negative feedback loop in the one-dimensional dynamics of the compound activity. Similarly, a change of coordinates exposes an effective negative feedback loop in the compound dynamics of stable excitatory-inhibitory networks. The suppression of input correlations in finite networks is explained by the population averaged correlations in the linear network model: In purely inhibitory networks, shared-input correlations are canceled by negative spike-train correlations. In excitatory-inhibitory networks, spike-train correlations are typically positive. Here, the suppression of input correlations is not a result of the mere existence of correlations between </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active">20</li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active">21</li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4250444','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4250444">Social closeness and feedback modulate susceptibility to the framing effect</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Sip, Kamila E.; Smith, David V.; Porcelli, Anthony J.; Kar, Kohitij; Delgado, Mauricio R. 2014-01-01 Although, we often seek social feedback from others to help us make decisions, little is known about how social feedback affects decisions under risk, particularly from a close peer. We conducted two experiments using an established framing task to probe how decision making is modulated by social feedback valence (positive, negative) and the level of closeness with feedback provider (friend, confederate). Participants faced mathematically equivalent decisions framed as either an opportunity to keep (gain frame) or lose (loss frame) part of an initial endowment. Periodically, participants were provided with positive (e.g., “Nice!”) or negative (e.g., “Lame!”) feedback about their choices. Such feedback was provided by either a confederate (Experiment 1), or a gender-matched close friend (Experiment 2). As expected, the framing effect was observed in both experiments. Critically, an individual’s susceptibility to the framing effect was modulated by the valence of the social feedback, but only when the feedback provider was a close friend. This effect was reflected in the activation patterns of ventromedial prefrontal cortex and posterior cingulate cortex, regions involved in complex decision making. Taken together, these results highlight social closeness as an important factor in understanding the impact of social feedback on neural mechanisms of decision making. PMID:25074501 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=ELEMENTS+AND+OF+AND+THE+AND+DECISION+AND+MAKING+AND+PROCESS&pg=3&id=ED582890','ERIC'); return false;" href="https://eric.ed.gov/?q=ELEMENTS+AND+OF+AND+THE+AND+DECISION+AND+MAKING+AND+PROCESS&pg=3&id=ED582890">Beyond Barriers: Encouraging Teacher Use of Feedback Resources. A Report from the Teacher Feedback Resources Project</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Morgan, Nicholas; Killion, Joellen 2018-01-01 This report investigates factors that drive teachers to embrace or challenge the use of products and services designed to support improvements in practice. Key elements of the study include: (1) Technology-based resources studied include those designed for video observations, peer feedback and collaboration, online professional learning, and… </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017Chaos..27k4320Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017Chaos..27k4320Z">Time-delayed feedback control of coherence resonance chimeras</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Zakharova, Anna; Semenova, Nadezhda; Anishchenko, Vadim; Schöll, Eckehard 2017-11-01 Using the model of a FitzHugh-Nagumo system in the excitable regime, we investigate the influence of time-delayed feedback on noise-induced chimera states in a network with nonlocal coupling, i.e., coherence resonance chimeras. It is shown that time-delayed feedback allows for the control of the range of parameter values where these chimera states occur. Moreover, for the feedback delay close to the intrinsic period of the system, we find a novel regime which we call period-two coherence resonance chimera. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28712529','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28712529">Dynamic simulation of knee-joint loading during gait using force-feedback control and surrogate contact modelling.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Walter, Jonathan P; Pandy, Marcus G 2017-10-01 The aim of this study was to perform multi-body, muscle-driven, forward-dynamics simulations of human gait using a 6-degree-of-freedom (6-DOF) model of the knee in tandem with a surrogate model of articular contact and force control. A forward-dynamics simulation incorporating position, velocity and contact force-feedback control (FFC) was used to track full-body motion capture data recorded for multiple trials of level walking and stair descent performed by two individuals with instrumented knee implants. Tibiofemoral contact force errors for FFC were compared against those obtained from a standard computed muscle control algorithm (CMC) with a 6-DOF knee contact model (CMC6); CMC with a 1-DOF translating hinge-knee model (CMC1); and static optimization with a 1-DOF translating hinge-knee model (SO). Tibiofemoral joint loads predicted by FFC and CMC6 were comparable for level walking, however FFC produced more accurate results for stair descent. SO yielded reasonable predictions of joint contact loading for level walking but significant differences between model and experiment were observed for stair descent. CMC1 produced the least accurate predictions of tibiofemoral contact loads for both tasks. Our findings suggest that reliable estimates of knee-joint loading may be obtained by incorporating position, velocity and force-feedback control with a multi-DOF model of joint contact in a forward-dynamics simulation of gait. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=business+AND+law&pg=7&id=EJ1153239','ERIC'); return false;" href="https://eric.ed.gov/?q=business+AND+law&pg=7&id=EJ1153239">The Impact of Student Feedback on Teaching in Higher Education</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Flodén, Jonas 2017-01-01 Receiving feedback from students has become a normal part of life for university teachers worldwide. This puts pressure on them from several sides and may be an influential factor that leads them to tailor their teaching to students' preferences. The aim of this study was to investigate teachers' perceptions of student feedback and how it affects… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26263382','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26263382">Effects of invalid feedback on learning and feedback-related brain activity in decision-making.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Ernst, Benjamin; Steinhauser, Marco 2015-10-01 For adaptive decision-making it is important to utilize only relevant, valid and to ignore irrelevant feedback. The present study investigated how feedback processing in decision-making is impaired when relevant feedback is combined with irrelevant and potentially invalid feedback. We analyzed two electrophysiological markers of feedback processing, the feedback-related negativity (FRN) and the P300, in a simple decision-making task, in which participants processed feedback stimuli consisting of relevant and irrelevant feedback provided by the color and meaning of a Stroop stimulus. We found that invalid, irrelevant feedback not only impaired learning, it also altered the amplitude of the P300 to relevant feedback, suggesting an interfering effect of irrelevant feedback on the processing of relevant feedback. In contrast, no such effect on the FRN was obtained. These results indicate that detrimental effects of invalid, irrelevant feedback result from failures of controlled feedback processing. Copyright © 2015 Elsevier Inc. All rights reserved. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018NatGe..11...44S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018NatGe..11...44S">Substantial large-scale feedbacks between natural aerosols and climate</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Scott, C. E.; Arnold, S. R.; Monks, S. A.; Asmi, A.; Paasonen, P.; Spracklen, D. V. 2018-01-01 The terrestrial biosphere is an important source of natural aerosol. Natural aerosol sources alter climate, but are also strongly controlled by climate, leading to the potential for natural aerosol-climate feedbacks. Here we use a global aerosol model to make an assessment of terrestrial natural aerosol-climate feedbacks, constrained by observations of aerosol number. We find that warmer-than-average temperatures are associated with higher-than-average number concentrations of large (>100 nm diameter) particles, particularly during the summer. This relationship is well reproduced by the model and is driven by both meteorological variability and variability in natural aerosol from biogenic and landscape fire sources. We find that the calculated extratropical annual mean aerosol radiative effect (both direct and indirect) is negatively related to the observed global temperature anomaly, and is driven by a positive relationship between temperature and the emission of natural aerosol. The extratropical aerosol-climate feedback is estimated to be -0.14 W m-2 K-1 for landscape fire aerosol, greater than the -0.03 W m-2 K-1 estimated for biogenic secondary organic aerosol. These feedbacks are comparable in magnitude to other biogeochemical feedbacks, highlighting the need for natural aerosol feedbacks to be included in climate simulations. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19720034045&hterms=evaluative&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Devaluative','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19720034045&hterms=evaluative&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Devaluative">Motivation in vigilance - Effects of self-evaluation and experimenter-controlled feedback.</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Warm, J. S.; Kanfer, F. H.; Kuwada, S.; Clark, J. L. 1972-01-01 Vigilance experiments have been performed to study the relative efficiency of feedback operations in enhancing vigilance performance. Two feedback operations were compared - i.e., experimenter-controlled feedback in the form of knowledge of results (KR) regarding response times to signal detections, and subject-controlled feedback in the form of self-evaluation (SE) of response times to signal detections. The subjects responded to the aperiodic offset of a visual signal during a 1-hr vigil. Both feedback operations were found to enhance performance efficiency: subjects in the KR and SE conditions had faster response times than controls receiving no evaluative feedback. Moreover, the data of the KR and SE groups did not differ significantly from each other. The results are discussed in terms of the hypothesis that self-evaluation is a critical factor underlying the incentive value of KR in vigilance tasks. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28889779','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28889779">Physician performance feedback in a Canadian academic center.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Garvin, Dennis; Worthington, James; McGuire, Shaun; Burgetz, Stephanie; Forster, Alan J; Patey, Andrea; Gerin-Lajoie, Caroline; Turnbull, Jeffrey; Roth, Virginia 2017-10-02 Purpose This paper aims at the implementation and early evaluation of a comprehensive, formative annual physician performance feedback process in a large academic health-care organization. Design/methodology/approach A mixed methods approach was used to introduce a formative feedback process to provide physicians with comprehensive feedback on performance and to support professional development. This initiative responded to organization-wide engagement surveys through which physicians identified effective performance feedback as a priority. In 2013, physicians primarily affiliated with the organization participated in a performance feedback process, and physician satisfaction and participant perceptions were explored through participant survey responses and physician leader focus groups. Training was required for physician leaders prior to conducting performance feedback discussions. Findings This process was completed by 98 per cent of eligible physicians, and 30 per cent completed an evaluation survey. While physicians endorsed the concept of a formative feedback process, process improvement opportunities were identified. Qualitative analysis revealed the following process improvement themes: simplify the tool, ensure leaders follow process, eliminate redundancies in data collection (through academic or licensing requirements) and provide objective quality metrics. Following physician leader training on performance feedback, 98 per cent of leaders who completed an evaluation questionnaire agreed or strongly agreed that the performance feedback process was useful and that training objectives were met. Originality/value This paper introduces a physician performance feedback model, leadership training approach and first-year implementation outcomes. The results of this study will be useful to health administrators and physician leaders interested in implementing physician performance feedback or improving physician engagement. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1236365-deterministic-generation-remote-entanglement-active-quantum-feedback','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1236365-deterministic-generation-remote-entanglement-active-quantum-feedback">Deterministic generation of remote entanglement with active quantum feedback</a> <a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a> Martin, Leigh; Motzoi, Felix; Li, Hanhan; ... 2015-12-10 We develop and study protocols for deterministic remote entanglement generation using quantum feedback, without relying on an entangling Hamiltonian. In order to formulate the most effective experimentally feasible protocol, we introduce the notion of average-sense locally optimal feedback protocols, which do not require real-time quantum state estimation, a difficult component of real-time quantum feedback control. We use this notion of optimality to construct two protocols that can deterministically create maximal entanglement: a semiclassical feedback protocol for low-efficiency measurements and a quantum feedback protocol for high-efficiency measurements. The latter reduces to direct feedback in the continuous-time limit, whose dynamics can bemore » modeled by a Wiseman-Milburn feedback master equation, which yields an analytic solution in the limit of unit measurement efficiency. Our formalism can smoothly interpolate between continuous-time and discrete-time descriptions of feedback dynamics and we exploit this feature to derive a superior hybrid protocol for arbitrary nonunit measurement efficiency that switches between quantum and semiclassical protocols. Lastly, we show using simulations incorporating experimental imperfections that deterministic entanglement of remote superconducting qubits may be achieved with current technology using the continuous-time feedback protocol alone.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29197382','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29197382">Beyond quality improvement: exploring why primary care teams engage in a voluntary audit and feedback program.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Wagner, Daniel J; Durbin, Janet; Barnsley, Jan; Ivers, Noah M 2017-12-02 Despite its popularity, the effectiveness of audit and feedback in support quality improvement efforts is mixed. While audit and feedback-related research efforts have investigated issues relating to feedback design and delivery, little attention has been directed towards factors which motivate interest and engagement with feedback interventions. This study explored the motivating factors that drove primary care teams to participate in a voluntary audit and feedback initiative. Interviews were conducted with leaders of primary care teams who had participated in at least one iteration of the audit and feedback program. This intervention was developed by an organization which advocates for high-quality, team-based primary care in Ontario, Canada. Interview transcripts were coded using the Consolidated Framework for Implementation Research and the resulting framework was analyzed inductively to generate key themes. Interviews were completed with 25 individuals from 18 primary care teams across Ontario. The majority were Executive Directors (14), Physician leaders (3) and support staff for Quality Improvement (4). A range of motivations for participating in the audit and feedback program beyond quality improvement were emphasized. Primarily, informants believed that the program would eventually become a best-in-class audit and feedback initiative. This reflected concerns regarding existing initiatives in terms of the intervention components and intentions as well as the perception that an initiative by primary care, for primary care would better reflect their own goals and better support desired patient outcomes. Key enablers included perceived obligations to engage and provision of support for the work involved. No teams cited an evidence base for A&F as a motivating factor for participation. A range of motivating factors, beyond quality improvement, contributed to participation in the audit and feedback program. Findings from this study highlight that efforts to </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy...48.1109W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy...48.1109W">The Alpine snow-albedo feedback in regional climate models</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Winter, Kevin J.-P. M.; Kotlarski, Sven; Scherrer, Simon C.; Schär, Christoph 2017-02-01 The effect of the snow-albedo feedback (SAF) on 2m temperatures and their future changes in the European Alps is investigated in the ENSEMBLES regional climate models (RCMs) with a focus on the spring season. A total of 14 re-analysis-driven RCM experiments covering the period 1961-2000 and 10 GCM-driven transient climate change projections for 1950-2099 are analysed. A positive springtime SAF is found in all RCMs, but the range of the diagnosed SAF is large. Results are compared against an observation-based SAF estimate. For some RCMs, values very close to this estimate are found; other models show a considerable overestimation of the SAF. Net shortwave radiation has the largest influence of all components of the energy balance on the diagnosed SAF and can partly explain its spatial variability. Model deficiencies in reproducing 2m temperatures above snow and ice and associated cold temperature biases at high elevations seem to contribute to a SAF overestimation in several RCMs. The diagnosed SAF in the observational period strongly influences the estimated SAF contribution to twenty first century temperature changes in the European Alps. This contribution is subject to a clear elevation dependency that is governed by the elevation-dependent change in the number of snow days. Elevations of maximum SAF contribution range from 1500 to 2000 m in spring and are found above 2000 m in summer. Here, a SAF contribution to the total simulated temperature change between 0 and 0.5 °C until 2099 (multi-model mean in spring: 0.26 °C) or 0 and 14 % (multi-model mean in spring: 8 %) is obtained for models showing a realistic SAF. These numbers represent a well-funded but only approximate estimate of the SAF contribution to future warming, and a remaining contribution of model-specific SAF misrepresentations cannot be ruled out. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/1406917-enhanced-reproducibility-mode-plasma-discharges-via-physics-model-based-profile-feedback-control-diii','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/1406917-enhanced-reproducibility-mode-plasma-discharges-via-physics-model-based-profile-feedback-control-diii">Enhanced reproducibility of L-mode plasma discharges via physics-model-based q-profile feedback control in DIII-D</a> <a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a> Schuster, Eugenio J.; Wehner, William P.; Barton, Joseph E. Recent experiments on DIII-D demonstrate the potential of physics-model-based q-profile control to improve reproducibility of plasma discharges. A combined feed forward + feedback control scheme is employed to optimize the current ramp-up phase by consistently achieving target q profiles (Target 1: q min = 1.3,q 95 = 4:4; Target 2: q min = 1.65,q 95 = 5.0; Target 3: q min = 2.1,q 95 = 6:2) at prescribed times during the plasma formation phase (Target 1: t = 1.5 s; Target 2: t = 1:3 s; Target 3: t = 1.0 s). At the core of the control scheme ismore » a nonlinear, first-principles-driven, physics-based, control-oriented model of the plasma dynamics valid for low confinement (L-mode) scenarios. To prevent undesired L-H transitions, a constraint on the maximum allowable total auxiliary power is imposed in addition to the maximum powers for the individual heating and current-drive sources. Experimental results are presented to demonstrate the effectiveness of the combined feed forward + feedback control scheme to consistently achieve the desired target profiles at the predefined times. Here, these results also show how the addition of feedback control significantly improves upon the feed forward only control solution by reducing the matching error and also how the feedback controller is able to reduce the matching error as the constraint on the maximum allowable total auxiliary power is relaxed while keeping the plasma in L-mode.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1406917-enhanced-reproducibility-mode-plasma-discharges-via-physics-model-based-profile-feedback-control-diii','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1406917-enhanced-reproducibility-mode-plasma-discharges-via-physics-model-based-profile-feedback-control-diii">Enhanced reproducibility of L-mode plasma discharges via physics-model-based q-profile feedback control in DIII-D</a> <a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a> Schuster, Eugenio J.; Wehner, William P.; Barton, Joseph E.; ... 2017-08-09 Recent experiments on DIII-D demonstrate the potential of physics-model-based q-profile control to improve reproducibility of plasma discharges. A combined feed forward + feedback control scheme is employed to optimize the current ramp-up phase by consistently achieving target q profiles (Target 1: q min = 1.3,q 95 = 4:4; Target 2: q min = 1.65,q 95 = 5.0; Target 3: q min = 2.1,q 95 = 6:2) at prescribed times during the plasma formation phase (Target 1: t = 1.5 s; Target 2: t = 1:3 s; Target 3: t = 1.0 s). At the core of the control scheme ismore » a nonlinear, first-principles-driven, physics-based, control-oriented model of the plasma dynamics valid for low confinement (L-mode) scenarios. To prevent undesired L-H transitions, a constraint on the maximum allowable total auxiliary power is imposed in addition to the maximum powers for the individual heating and current-drive sources. Experimental results are presented to demonstrate the effectiveness of the combined feed forward + feedback control scheme to consistently achieve the desired target profiles at the predefined times. Here, these results also show how the addition of feedback control significantly improves upon the feed forward only control solution by reducing the matching error and also how the feedback controller is able to reduce the matching error as the constraint on the maximum allowable total auxiliary power is relaxed while keeping the plasma in L-mode.« less </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018DDA....4930303W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018DDA....4930303W">Implications of Stellar Feedback for Dynamical Modeling of the Milky Way and Dwarf Galaxies</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Wetzel, Andrew 2018-04-01 I will present recent results on dynamical modeling of stellar populations from the FIRE cosmological zoom-in baryonic simulations of Milky Way-like and dwarf galaxies. First, I will discuss the dynamical formation of the Milky Way, including the origin of thin+thick stellar disk morphology. I also will discuss the curious origin of metal-rich stars on halo-like orbits near the Sun, as recently measured by Gaia, with new insights from FIRE simulations on stellar radial migration/heating. Next, I will discuss role of stellar feedback in generating non-equilibrium fluctuations of the gravitational potential in low-mass 'dwarf' galaxies, which can explain the origin of cores in their dark-matter density profiles. In particular, we predict significant observable effects on stellar dynamics, including radial migration, size fluctuations, and population gradients, which can provide observational tests of feedback-driven core formation. Finally, this scenario can explain the formation of newly discovered 'ultra-diffuse' galaxies. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4248023','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4248023">MEK-Dependent Negative Feedback Underlies BCR-ABL-Mediated Oncogene Addiction</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Asmussen, Jennifer; Lasater, Elisabeth A.; Tajon, Cheryl; Oses-Prieto, Juan; Jun, Young-wook; Taylor, Barry S.; Burlingame, Alma; Craik, Charles S.; Shah, Neil P. 2014-01-01 The clinical experience with BCR-ABL tyrosine kinase inhibitors (TKIs) for the treatment of chronic myeloid leukemia (CML) provides compelling evidence for oncogene addiction. Yet, the molecular basis of oncogene addiction remains elusive. Through unbiased quantitative phosphoproteomic analyses of CML cells transiently exposed to BCR-ABL TKI, we identified persistent downregulation of growth factor receptor (GF-R) signaling pathways. We then established and validated a tissue-relevant isogenic model of BCR-ABL-mediated addiction, and found evidence for myeloid GF-R signaling pathway rewiring that profoundly and persistently dampens physiologic pathway activation. We demonstrate that eventual restoration of ligand-mediated GF-R pathway activation is insufficient to fully rescue cells from a competing apoptotic fate. In contrast to previous work with BRAFV600E in melanoma cells, feedback inhibition following BCR-ABL TKI treatment is markedly prolonged, extending beyond the time required to initiate apoptosis. Mechanistically, BCR-ABL-mediated oncogene addiction is facilitated by persistent high levels of MEK-dependent negative feedback. PMID:24362263 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4046020','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4046020">A combined model of human erythropoiesis and granulopoiesis under growth factor and chemotherapy treatment</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> 2014-01-01 Background Haematotoxicity of conventional chemotherapies often results in delays of treatment or reduction of chemotherapy dose. To ameliorate these side-effects, patients are routinely treated with blood transfusions or haematopoietic growth factors such as erythropoietin (EPO) or granulocyte colony-stimulating factor (G-CSF). For the latter ones, pharmaceutical derivatives are available, which differ in absorption kinetics, pharmacokinetic and -dynamic properties. Due to the complex interaction of cytotoxic effects of chemotherapy and the stimulating effects of different growth factor derivatives, optimal treatment is a non-trivial task. In the past, we developed mathematical models of thrombopoiesis, granulopoiesis and erythropoiesis under chemotherapy and growth-factor applications which can be used to perform clinically relevant predictions regarding the feasibility of chemotherapy schedules and cytopenia prophylaxis with haematopoietic growth factors. However, interactions of lineages and growth-factors were ignored so far. Results To close this gap, we constructed a hybrid model of human granulopoiesis and erythropoiesis under conventional chemotherapy, G-CSF and EPO applications. This was achieved by combining our single lineage models of human erythropoiesis and granulopoiesis with a common stem cell model. G-CSF effects on erythropoiesis were also implemented. Pharmacodynamic models are based on ordinary differential equations describing proliferation and maturation of haematopoietic cells. The system is regulated by feedback loops partly mediated by endogenous and exogenous EPO and G-CSF. Chemotherapy is modelled by depletion of cells. Unknown model parameters were determined by fitting the model predictions to time series data of blood counts and cytokine profiles. Data were extracted from literature or received from cooperating clinical study groups. Our model explains dynamics of mature blood cells and cytokines after growth-factor applications in </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=teaching+AND+mathematics+AND+e-learning&pg=5&id=EJ826507','ERIC'); return false;" href="https://eric.ed.gov/?q=teaching+AND+mathematics+AND+e-learning&pg=5&id=EJ826507">The Effects of Cooperative Learning and Feedback on E-Learning in Statistics</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Krause, Ulrike-Marie; Stark, Robin; Mandl, Heinz 2009-01-01 This study examined whether cooperative learning and feedback facilitate situated, example-based e-learning in the field of statistics. The factors "social context" (individual vs. cooperative) and "feedback intervention" (available vs. not available) were varied; participants were 137 university students. Results showed that… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26221437','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26221437">Barriers and Facilitators to Effective Feedback: A Qualitative Analysis of Data From Multispecialty Resident Focus Groups.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Reddy, Shalini T; Zegarek, Matthew H; Fromme, H Barrett; Ryan, Michael S; Schumann, Sarah-Anne; Harris, Ilene B 2015-06-01 Despite the importance of feedback, the literature suggests that there is inadequate feedback in graduate medical education. We explored barriers and facilitators that residents in anesthesiology, emergency medicine, obstetrics and gynecology, and surgery experience with giving and receiving feedback during their clinical training. Residents from 3 geographically diverse teaching institutions were recruited to participate in focus groups in 2012. Open-ended questions prompted residents to describe their experiences with giving and receiving feedback, and discuss facilitators and barriers. Data were transcribed and analyzed using the constant comparative method associated with a grounded theory approach. A total of 19 residents participated in 1 of 3 focus groups. Five major themes related to feedback were identified: teacher factors, learner factors, feedback process, feedback content, and educational context. Unapproachable attendings, time pressures due to clinical work, and discomfort with giving negative feedback were cited as major barriers in the feedback process. Learner engagement in the process was a major facilitator in the feedback process. Residents provided insights for improving the feedback process based on their dual roles as teachers and learners. Time pressures in the learning environment may be mitigated by efforts to improve the quality of teacher-learner relationships. Forms for collecting written feedback should be augmented by faculty development to ensure meaningful use. Efforts to improve residents' comfort with giving feedback and encouraging learners to engage in the feedback process may foster an environment conducive to increasing feedback. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5504241','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5504241">Ethical Leadership, Leader-Member Exchange and Feedback Seeking: A Double-Moderated Mediation Model of Emotional Intelligence and Work-Unit Structure</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Qian, Jing; Wang, Bin; Han, Zhuo; Song, Baihe 2017-01-01 This research elucidates the role of ethical leadership in employee feedback seeking by examining how and when ethical leadership may exert a positive influence on feedback seeking. Using matched reports from 64 supervisors and 265 of their immediate employees from a hotel group located in a major city in China, we proposed and tested a moderated mediation model that examines leader-member exchange (LMX) as the mediator and emotional intelligence as well as work-unit structure as double moderators in the relationships between ethical leadership and followers’ feedback-seeking behavior from supervisors and coworkers. Our findings indicated that (1) LMX mediated the positive relationship between ethical leadership and feedback seeking from both ethical leaders and coworkers, and (2) emotional intelligence and work-unit structure served as joint moderators on the mediated positive relationship in such a way that the relationship was strongest when the emotional intelligence was high and work-unit structure was more of an organic structure rather than a mechanistic structure. PMID:28744251 </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active">21</li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active">22</li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28744251','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28744251">Ethical Leadership, Leader-Member Exchange and Feedback Seeking: A Double-Moderated Mediation Model of Emotional Intelligence and Work-Unit Structure.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Qian, Jing; Wang, Bin; Han, Zhuo; Song, Baihe 2017-01-01 This research elucidates the role of ethical leadership in employee feedback seeking by examining how and when ethical leadership may exert a positive influence on feedback seeking. Using matched reports from 64 supervisors and 265 of their immediate employees from a hotel group located in a major city in China, we proposed and tested a moderated mediation model that examines leader-member exchange (LMX) as the mediator and emotional intelligence as well as work-unit structure as double moderators in the relationships between ethical leadership and followers' feedback-seeking behavior from supervisors and coworkers. Our findings indicated that (1) LMX mediated the positive relationship between ethical leadership and feedback seeking from both ethical leaders and coworkers, and (2) emotional intelligence and work-unit structure served as joint moderators on the mediated positive relationship in such a way that the relationship was strongest when the emotional intelligence was high and work-unit structure was more of an organic structure rather than a mechanistic structure. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013PhRvE..87c2722W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PhRvE..87c2722W">Strong feedback limit of the Goodwin circadian oscillator</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Woller, Aurore; Gonze, Didier; Erneux, Thomas 2013-03-01 The three-variable Goodwin model constitutes a prototypical oscillator based on a negative feedback loop. It was used as a minimal model for circadian oscillations. Other core models for circadian clocks are variants of the Goodwin model. The Goodwin oscillator also appears in many studies of coupled oscillator networks because of its relative simplicity compared to other biophysical models involving a large number of variables and parameters. Because the synchronization properties of Goodwin oscillators still remain difficult to explore mathematically, further simplifications of the Goodwin model have been sought. In this paper, we investigate the strong negative feedback limit of Goodwin equations by using asymptotic techniques. We find that Goodwin oscillations approach a sequence of decaying exponentials that can be described in terms of a single-variable leaky integrated-and-fire model. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24427208','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24427208">Effect of inhibitory feedback on correlated firing of spiking neural network.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Xie, Jinli; Wang, Zhijie 2013-08-01 Understanding the properties and mechanisms that generate different forms of correlation is critical for determining their role in cortical processing. Researches on retina, visual cortex, sensory cortex, and computational model have suggested that fast correlation with high temporal precision appears consistent with common input, and correlation on a slow time scale likely involves feedback. Based on feedback spiking neural network model, we investigate the role of inhibitory feedback in shaping correlations on a time scale of 100 ms. Notably, the relationship between the correlation coefficient and inhibitory feedback strength is non-monotonic. Further, computational simulations show how firing rate and oscillatory activity form the basis of the mechanisms underlying this relationship. When the mean firing rate holds unvaried, the correlation coefficient increases monotonically with inhibitory feedback, but the correlation coefficient keeps decreasing when the network has no oscillatory activity. Our findings reveal that two opposing effects of the inhibitory feedback on the firing activity of the network contribute to the non-monotonic relationship between the correlation coefficient and the strength of the inhibitory feedback. The inhibitory feedback affects the correlated firing activity by modulating the intensity and regularity of the spike trains. Finally, the non-monotonic relationship is replicated with varying transmission delay and different spatial network structure, demonstrating the universality of the results. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018GeoRL..45.1972S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018GeoRL..45.1972S">Multidecadal Variability in Surface Albedo Feedback Across CMIP5 Models</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Schneider, Adam; Flanner, Mark; Perket, Justin 2018-02-01 Previous studies quantify surface albedo feedback (SAF) in climate change, but few assess its variability on decadal time scales. Using the Coupled Model Intercomparison Project Version 5 (CMIP5) multimodel ensemble data set, we calculate time evolving SAF in multiple decades from surface albedo and temperature linear regressions. Results are meaningful when temperature change exceeds 0.5 K. Decadal-scale SAF is strongly correlated with century-scale SAF during the 21st century. Throughout the 21st century, multimodel ensemble mean SAF increases from 0.37 to 0.42 W m-2 K-1. These results suggest that models' mean decadal-scale SAFs are good estimates of their century-scale SAFs if there is at least 0.5 K temperature change. Persistent SAF into the late 21st century indicates ongoing capacity for Arctic albedo decline despite there being less sea ice. If the CMIP5 multimodel ensemble results are representative of the Earth, we cannot expect decreasing Arctic sea ice extent to suppress SAF in the 21st century. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010SPIE.7750E..0TM','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010SPIE.7750E..0TM">Optimizing the feedback control of Galvo scanners for laser manufacturing systems</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Mirtchev, Theodore; Weeks, Robert; Minko, Sergey 2010-06-01 This paper summarizes the factors that limit the performance of moving-magnet galvo scanners driven by closed-loop digital servo amplifiers: torsional resonances, drifts, nonlinearities, feedback noise and friction. Then it describes a detailed Simulink® simulator that takes into account these factors and can be used to automatically tune the controller for best results with given galvo type and trajectory patterns. It allows for rapid testing of different control schemes, for instance combined position/velocity PID loops and displays the corresponding output in terms of torque, angular position and feedback sensor signal. The tool is configurable and can either use a dynamical state-space model of galvo's open-loop response, or can import the experimentally measured frequency domain transfer function. Next a drive signal digital pre-filtering technique is discussed. By performing a real-time Fourier analysis of the raw command signal it can be pre-warped to minimize all harmonics around the torsional resonances while boosting other non-resonant high frequencies. The optimized waveform results in much smaller overshoot and better settling time. Similar performance gain cannot be extracted from the servo controller alone. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3338401','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3338401">Barriers and attitudes influencing non-engagement in a peer feedback model to inform evidence for GP appraisal</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> 2012-01-01 Background The UK general practitioner (GP) appraisal system is deemed to be an inadequate source of performance evidence to inform a future medical revalidation process. A long-running voluntary model of external peer review in the west of Scotland provides feedback by trained peers on the standard of GP colleagues' core appraisal activities and may 'add value' in strengthening the robustness of the current system in support of revalidation. A significant minority of GPs has participated in the peer feedback model, but a clear majority has yet to engage with it. We aimed to explore the views of non-participants to identify barriers to engagement and attitudes to external peer review as a means to inform the current appraisal system. Methods We conducted semi-structured interviews with a sample of west of Scotland GPs who had yet to participate in the peer review model. A thematic analysis of the interview transcriptions was conducted using a constant comparative approach. Results 13 GPs were interviewed of whom nine were males. Four core themes were identified in relation to the perceived and experienced 'value' placed on the topics discussed and their relevance to routine clinical practice and professional appraisal: 1. Value of the appraisal improvement activity. 2. Value of external peer review. 3. Value of the external peer review model and host organisation and 4. Attitudes to external peer review. Conclusions GPs in this study questioned the 'value' of participation in the external peer review model and the national appraisal system over the standard of internal feedback received from immediate work colleagues. There was a limited understanding of the concept, context and purpose of external peer review and some distrust of the host educational provider. Future engagement with the model by these GPs is likely to be influenced by policy to improve the standard of appraisal and contractual related activities, rather than a self-directed recognition of learning </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22443714','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22443714">Barriers and attitudes influencing non-engagement in a peer feedback model to inform evidence for GP appraisal.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Curnock, Esther; Bowie, Paul; Pope, Lindsey; McKay, John 2012-03-23 The UK general practitioner (GP) appraisal system is deemed to be an inadequate source of performance evidence to inform a future medical revalidation process. A long-running voluntary model of external peer review in the west of Scotland provides feedback by trained peers on the standard of GP colleagues' core appraisal activities and may 'add value' in strengthening the robustness of the current system in support of revalidation. A significant minority of GPs has participated in the peer feedback model, but a clear majority has yet to engage with it. We aimed to explore the views of non-participants to identify barriers to engagement and attitudes to external peer review as a means to inform the current appraisal system. We conducted semi-structured interviews with a sample of west of Scotland GPs who had yet to participate in the peer review model. A thematic analysis of the interview transcriptions was conducted using a constant comparative approach. 13 GPs were interviewed of whom nine were males. Four core themes were identified in relation to the perceived and experienced 'value' placed on the topics discussed and their relevance to routine clinical practice and professional appraisal: 1. Value of the appraisal improvement activity. 2. Value of external peer review. 3. Value of the external peer review model and host organisation and 4. Attitudes to external peer review. GPs in this study questioned the 'value' of participation in the external peer review model and the national appraisal system over the standard of internal feedback received from immediate work colleagues. There was a limited understanding of the concept, context and purpose of external peer review and some distrust of the host educational provider. Future engagement with the model by these GPs is likely to be influenced by policy to improve the standard of appraisal and contractual related activities, rather than a self-directed recognition of learning needs. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4466796','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4466796">Mitogen-Inducible Gene-6 Mediates Feedback Inhibition from Mutated BRAF towards the Epidermal Growth Factor Receptor and Thereby Limits Malignant Transformation</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Milewska, Malgorzata; Romano, David; Herrero, Ana; Guerriero, Maria Luisa; Birtwistle, Marc; Quehenberger, Franz; Hatzl, Stefan; Kholodenko, Boris N.; Segatto, Oreste; Kolch, Walter; Zebisch, Armin 2015-01-01 BRAF functions in the RAS-extracellular signal-regulated kinase (ERK) signaling cascade. Activation of this pathway is necessary to mediate the transforming potential of oncogenic BRAF, however, it may also cause a negative feedback that inhibits the epidermal growth factor receptor (EGFR). Mitogen-inducible gene-6 (MIG-6) is a potent inhibitor of the EGFR and has been demonstrated to function as a tumor suppressor. As MIG-6 can be induced via RAS-ERK signaling, we investigated its potential involvement in this negative regulatory loop. Focus formation assays were performed and demonstrated that MIG-6 significantly reduces malignant transformation induced by oncogenic BRAF. Although this genetic interaction was mirrored by a physical interaction between MIG-6 and BRAF, we did not observe a direct regulation of BRAF kinase activity by MIG-6. Interestingly, a selective chemical EGFR inhibitor suppressed transformation to a similar degree as MIG-6, whereas combining these approaches had no synergistic effect. By analyzing a range of BRAF mutated and wildtype cell line models, we could show that BRAF V600E causes a strong upregulation of MIG-6, which was mediated at the transcriptional level via the RAS-ERK pathway and resulted in downregulation of EGFR activation. This feedback loop is operational in tumors, as shown by the analysis of almost 400 patients with papillary thyroid cancer (PTC). Presence of BRAF V600E correlated with increased MIG-6 expression on the one hand, and with inactivation of the EGFR and of PI3K/AKT signaling on the other hand. Importantly, we also observed a more aggressive disease phenotype when BRAF V600E coexisted with low MIG-6 expression. Finally, analysis of methylation data was performed and revealed that higher methylation of MIG-6 correlated to its decreased expression. Taken together, we demonstrate that MIG-6 efficiently reduces cellular transformation driven by oncogenic BRAF by orchestrating a negative feedback circuit directed </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28191003','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28191003">Want More? Learn Less: Motivation Affects Adolescents Learning from Negative Feedback.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Zhuang, Yun; Feng, Wenfeng; Liao, Yu 2017-01-01 The primary goal of the present study was to investigate how positive and negative feedback may differently facilitate learning throughout development. In addition, the role of motivation as a modulating factor was examined. Participants (children, adolescents, and adults) completed two forms of the guess and application task (GAT). Feedback from the Cool-GAT task has low motivational salience because there are no consequences, while feedback from the Hot-GAT task has high motivational salience as it pertains to receiving a reward. The results indicated that negative feedback leads to a reduction in learning compared to positive feedback. The effect of negative feedback was greater in adolescent participants compared to children and adults in the Hot-GAT task, suggesting an interaction between age and motivation level on learning. Further analysis indicated that greater risk was associated with a greater reduction in learning from negative feedback and again, the reduction was greatest in adolescents. In summary, the current study supports the idea that learning from positive feedback and negative feedback differs throughout development. In a rule-based learning task, when associative learning is primarily in practice, participants learned less from negative feedback. This reduction is amplified during adolescence when task-elicited motivation is high. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5271404','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5271404">Want More? Learn Less: Motivation Affects Adolescents Learning from Negative Feedback</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Zhuang, Yun; Feng, Wenfeng; Liao, Yu 2017-01-01 The primary goal of the present study was to investigate how positive and negative feedback may differently facilitate learning throughout development. In addition, the role of motivation as a modulating factor was examined. Participants (children, adolescents, and adults) completed two forms of the guess and application task (GAT). Feedback from the Cool-GAT task has low motivational salience because there are no consequences, while feedback from the Hot-GAT task has high motivational salience as it pertains to receiving a reward. The results indicated that negative feedback leads to a reduction in learning compared to positive feedback. The effect of negative feedback was greater in adolescent participants compared to children and adults in the Hot-GAT task, suggesting an interaction between age and motivation level on learning. Further analysis indicated that greater risk was associated with a greater reduction in learning from negative feedback and again, the reduction was greatest in adolescents. In summary, the current study supports the idea that learning from positive feedback and negative feedback differs throughout development. In a rule-based learning task, when associative learning is primarily in practice, participants learned less from negative feedback. This reduction is amplified during adolescence when task-elicited motivation is high. PMID:28191003 </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016BGeo...13.4945S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016BGeo...13.4945S">Wetland eco-engineering: measuring and modeling feedbacks of oxidation processes between plants and clay-rich material</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Saaltink, Rémon; Dekker, Stefan C.; Griffioen, Jasper; Wassen, Martin J. 2016-09-01 Interest is growing in using soft sediment as a foundation in eco-engineering projects. Wetland construction in the Dutch lake Markermeer is an example: here, dredging some of the clay-rich lake-bed sediment and using it to construct wetland will soon begin. Natural processes will be utilized during and after construction to accelerate ecosystem development. Knowing that plants can eco-engineer their environment via positive or negative biogeochemical plant-soil feedbacks, we conducted a 6-month greenhouse experiment to identify the key biogeochemical processes in the mud when Phragmites australis is used as an eco-engineering species. We applied inverse biogeochemical modeling to link observed changes in pore water composition to biogeochemical processes. Two months after transplantation we observed reduced plant growth and shriveling and yellowing of foliage. The N : P ratios of the plant tissue were low, and these were affected not by hampered uptake of N but by enhanced uptake of P. Subsequent analyses revealed high Fe concentrations in the leaves and roots. Sulfate concentrations rose drastically in our experiment due to pyrite oxidation; as reduction of sulfate will decouple Fe-P in reducing conditions, we argue that plant-induced iron toxicity hampered plant growth, forming a negative feedback loop, while simultaneously there was a positive feedback loop, as iron toxicity promotes P mobilization as a result of reduced conditions through root death, thereby stimulating plant growth and regeneration. Given these two feedback mechanisms, we propose the use of Fe-tolerant species rather than species that thrive in N-limited conditions. The results presented in this study demonstrate the importance of studying the biogeochemical properties of the situated sediment and the feedback mechanisms between plant and soil prior to finalizing the design of the eco-engineering project. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.A11M..03M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.A11M..03M">The Dependence of Cloud-SST Feedback on Circulation Regime and Timescale</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Middlemas, E.; Clement, A. C.; Medeiros, B. 2017-12-01 Studies suggest cloud radiative feedback amplifies internal variability of Pacific sea surface temperature (SST) on interannual-and-longer timescales, though only a few modeling studies have tested the quantitative importance of this feedback (Bellomo et al. 2014b, Brown et al. 2016, Radel et al. 2016 Burgman et al. 2017). We prescribe clouds from a previous control run in the radiation module in Community Atmospheric Model (CAM5-slab), a method called "cloud-locking". By comparing this run to a control run, in which cloud radiative forcing can feedback on the climate system, we isolate the effect of cloud radiative forcing on SST variability. Cloud-locking prevents clouds from radiatively interacting with atmospheric circulation, water vapor, and SST, while maintaining a similar mean state to the control. On all timescales, cloud radiative forcing's influence on SST variance is modulated by the circulation regime. Cloud radiative forcing amplifies SST variance in subsiding regimes and dampens SST variance in convecting regimes. In this particular model, a tug of war between latent heat flux and cloud radiative forcing determines the variance of SST, and the winner depends on the timescale. On decadal-and-longer timescales, cloud radiative forcing plays a relatively larger role than on interannual-and-shorter timescales, while latent heat flux plays a smaller role. On longer timescales, the absence of cloud radiative feedback changes SST variance in a zonally asymmetric pattern in the Pacific Ocean that resembles an IPO-like pattern. We also present an analysis of cloud feedback's role on Pacific SST variability among preindustrial control CMIP5 models to test the model robustness of our results. Our results suggest that circulation plays a crucial role in cloud-SST feedbacks across the globe and cloud radiative feedbacks cannot be ignored when studying SST variability on decadal-and-longer timescales. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28474292','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28474292">Brain activation upon ideal-body media exposure and peer feedback in late adolescent girls.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> van der Meulen, Mara; Veldhuis, Jolanda; Braams, Barbara R; Peters, Sabine; Konijn, Elly A; Crone, Eveline A 2017-08-01 Media's prevailing thin-body ideal plays a vital role in adolescent girls' body image development, but the co-occurring impact of peer feedback is understudied. The present study used functional magnetic resonance imaging (fMRI) to test media imagery and peer feedback combinations on neural activity related to thin-body ideals. Twenty-four healthy female late adolescents rated precategorized body sizes of bikini models (too thin or normal), directly followed by ostensible peer feedback (too thin or normal). Consistent with prior studies on social feedback processing, results showed increased brain activity in the dorsal medial prefrontal cortex (dmPFC)/anterior cingulate cortex (ACC) and bilateral insula in incongruent situations: when participants rated media models' body size as normal while peer feedback indicated the models as too thin (or vice versa). This effect was stronger for girls with lower self-esteem. A subsequent behavioral study (N = 34 female late adolescents, separate sample) demonstrated that participants changed behavior in the direction of the peer feedback: precategorized normal sized models were rated as too thin more often after receiving too thin peer feedback. This suggests that the neural responses upon peer feedback may influence subsequent choice. Our results show that media-by-peer interactions have pronounced effects on girls' body ideals. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11242721','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11242721">Comparison of an enhanced versus a written feedback model on the management of Medicare inpatients with venous thrombosis.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Hayes, R; Bratzler, D; Armour, B; Moore, L; Murray, C; Stevens, B R; Radford, M; Fitzgerald, D; Elward, K; Ballard, D J 2001-03-01 A multistate randomized study conducted under the Health Care Financing Administration's (HCFA's) Health Care Quality Improvement Program (HCQIP) offered the opportunity to compare the effect of a written feedback intervention (WFI) with that of an enhanced feedback intervention (EFI) on improving the anticoagulant management of Medicare beneficiaries who present to the hospital with venous thromboembolic disease. Twenty-nine hospitals in five states were randomly assigned to receive written hospital-specific feedback (WFI) of feedback enhanced by the participation of a trained physician, quality improvement tools, and an Anticoagulant Management of Venous Thrombosis (AMVT) project liaison (EFI). Differences in the performance of five quality indicators between baseline and remeasurement were assessed. Quality managers were interviewed to determine perceptions of project implementation. No significant differences in the change from baseline to remeasurement were found between the two intervention groups. Significant improvement in one indicator and significant decline in two indicators were found for one or both groups. Yet 59% of all quality managers perceived the AMVT project as being successful to very successful, and more EFI quality managers perceived success than did WFI managers (71% versus 40%). In the majority of EFI hospitals, physician liaisons played an important role in project implementation. Study results indicated that the addition of a physician liaison, quality improvement tools, and a project liaison did not provide incremental value to hospital-specific feedback for improving quality of care. Future studies with larger sample sizes, lengthier follow-up periods, and interventions that include more of the elements shown to affect practice behavior change are needed to identify an optimal feedback model for use by external quality management organizations. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5409484','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5409484">Glucocorticoid and cytokine crosstalk: Feedback, feedforward, and co-regulatory interactions determine repression or resistance</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Shah, Suharsh; Altonsy, Mohammed O.; Gerber, Antony N. 2017-01-01 Inflammatory signals induce feedback and feedforward systems that provide temporal control. Although glucocorticoids can repress inflammatory gene expression, glucocorticoid receptor recruitment increases expression of negative feedback and feedforward regulators, including the phosphatase, DUSP1, the ubiquitin-modifying enzyme, TNFAIP3, or the mRNA-destabilizing protein, ZFP36. Moreover, glucocorticoid receptor cooperativity with factors, including nuclear factor-κB (NF-κB), may enhance regulator expression to promote repression. Conversely, MAPKs, which are inhibited by glucocorticoids, provide feedforward control to limit expression of the transcription factor IRF1, and the chemokine, CXCL10. We propose that modulation of feedback and feedforward control can determine repression or resistance of inflammatory gene expression toglucocorticoid. PMID:28283576 </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013ClDy...40.1453K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013ClDy...40.1453K">A further assessment of vegetation feedback on decadal Sahel rainfall variability</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Kucharski, Fred; Zeng, Ning; Kalnay, Eugenia 2013-03-01 The effect of vegetation feedback on decadal-scale Sahel rainfall variability is analyzed using an ensemble of climate model simulations in which the atmospheric general circulation model ICTPAGCM ("SPEEDY") is coupled to the dynamic vegetation model VEGAS to represent feedbacks from surface albedo change and evapotranspiration, forced externally by observed sea surface temperature (SST) changes. In the control experiment, where the full vegetation feedback is included, the ensemble is consistent with the observed decadal rainfall variability, with a forced component 60 % of the observed variability. In a sensitivity experiment where climatological vegetation cover and albedo are prescribed from the control experiment, the ensemble of simulations is not consistent with the observations because of strongly reduced amplitude of decadal rainfall variability, and the forced component drops to 35 % of the observed variability. The decadal rainfall variability is driven by SST forcing, but significantly enhanced by land-surface feedbacks. Both, local evaporation and moisture flux convergence changes are important for the total rainfall response. Also the internal decadal variability across the ensemble members (not SST-forced) is much stronger in the control experiment compared with the one where vegetation cover and albedo are prescribed. It is further shown that this positive vegetation feedback is physically related to the albedo feedback, supporting the Charney hypothesis. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24110376','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24110376">Effect of vibrotactile feedback on an EMG-based proportional cursor control system.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Li, Shunchong; Chen, Xingyu; Zhang, Dingguo; Sheng, Xinjun; Zhu, Xiangyang 2013-01-01 Surface electromyography (sEMG) has been introduced into the bio-mechatronics systems, however, most of them are lack of the sensory feedback. In this paper, the effect of vibrotactile feedback for a myoelectric cursor control system is investigated quantitatively. Simultaneous and proportional control signals are extracted from EMG using a muscle synergy model. Different types of feedback including vibrotactile feedback and visual feedback are added, assessed and compared with each other. The results show that vibrotactile feedback is capable of improving the performance of EMG-based human machine interface. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4193330','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4193330">Neural dynamics of feedforward and feedback processing in figure-ground segregation</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Layton, Oliver W.; Mingolla, Ennio; Yazdanbakhsh, Arash 2014-01-01 Determining whether a region belongs to the interior or exterior of a shape (figure-ground segregation) is a core competency of the primate brain, yet the underlying mechanisms are not well understood. Many models assume that figure-ground segregation occurs by assembling progressively more complex representations through feedforward connections, with feedback playing only a modulatory role. We present a dynamical model of figure-ground segregation in the primate ventral stream wherein feedback plays a crucial role in disambiguating a figure's interior and exterior. We introduce a processing strategy whereby jitter in RF center locations and variation in RF sizes is exploited to enhance and suppress neural activity inside and outside of figures, respectively. Feedforward projections emanate from units that model cells in V4 known to respond to the curvature of boundary contours (curved contour cells), and feedback projections from units predicted to exist in IT that strategically group neurons with different RF sizes and RF center locations (teardrop cells). Neurons (convex cells) that preferentially respond when centered on a figure dynamically balance feedforward (bottom-up) information and feedback from higher visual areas. The activation is enhanced when an interior portion of a figure is in the RF via feedback from units that detect closure in the boundary contours of a figure. Our model produces maximal activity along the medial axis of well-known figures with and without concavities, and inside algorithmically generated shapes. Our results suggest that the dynamic balancing of feedforward signals with the specific feedback mechanisms proposed by the model is crucial for figure-ground segregation. PMID:25346703 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25346703','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25346703">Neural dynamics of feedforward and feedback processing in figure-ground segregation.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Layton, Oliver W; Mingolla, Ennio; Yazdanbakhsh, Arash 2014-01-01 Determining whether a region belongs to the interior or exterior of a shape (figure-ground segregation) is a core competency of the primate brain, yet the underlying mechanisms are not well understood. Many models assume that figure-ground segregation occurs by assembling progressively more complex representations through feedforward connections, with feedback playing only a modulatory role. We present a dynamical model of figure-ground segregation in the primate ventral stream wherein feedback plays a crucial role in disambiguating a figure's interior and exterior. We introduce a processing strategy whereby jitter in RF center locations and variation in RF sizes is exploited to enhance and suppress neural activity inside and outside of figures, respectively. Feedforward projections emanate from units that model cells in V4 known to respond to the curvature of boundary contours (curved contour cells), and feedback projections from units predicted to exist in IT that strategically group neurons with different RF sizes and RF center locations (teardrop cells). Neurons (convex cells) that preferentially respond when centered on a figure dynamically balance feedforward (bottom-up) information and feedback from higher visual areas. The activation is enhanced when an interior portion of a figure is in the RF via feedback from units that detect closure in the boundary contours of a figure. Our model produces maximal activity along the medial axis of well-known figures with and without concavities, and inside algorithmically generated shapes. Our results suggest that the dynamic balancing of feedforward signals with the specific feedback mechanisms proposed by the model is crucial for figure-ground segregation. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19..453L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19..453L">Feedbacks between climate change and biosphere integrity</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Lade, Steven; Anderies, J. Marty; Donges, Jonathan; Steffen, Will; Rockström, Johan; Richardson, Katherine; Cornell, Sarah; Norberg, Jon; Fetzer, Ingo 2017-04-01 The terrestrial and marine biospheres sink substantial fractions of human fossil fuel emissions. How the biosphere's capacity to sink carbon depends on biodiversity and other measures of biosphere integrity is however poorly understood. Here, we (1): review assumptions from literature regarding the relationships between the carbon cycle and the terrestrial and marine biospheres; and (2) explore the consequences of these different assumptions for climate feedbacks using the stylised carbon cycle model PB-INT. We find that: terrestrial biodiversity loss could significantly dampen climate-carbon cycle feedbacks; direct biodiversity effects, if they exist, could rival temperature increases from low-emission trajectories; and the response of the marine biosphere is critical for longer term climate change. Simple, low-dimensional climate models such as PB-INT can help assess the importance of still unknown or controversial earth system processes such as biodiversity loss for climate feedbacks. This study constitutes the first detailed study of the interactions between climate change and biosphere integrity, two of the 'planetary boundaries'. </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active">22</li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active">23</li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhyA..479..478W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhyA..479..478W">A lattice hydrodynamic model based on delayed feedback control considering the effect of flow rate difference</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Wang, Yunong; Cheng, Rongjun; Ge, Hongxia 2017-08-01 In this paper, a lattice hydrodynamic model is derived considering not only the effect of flow rate difference but also the delayed feedback control signal which including more comprehensive information. The control method is used to analyze the stability of the model. Furthermore, the critical condition for the linear steady traffic flow is deduced and the numerical simulation is carried out to investigate the advantage of the proposed model with and without the effect of flow rate difference and the control signal. The results are consistent with the theoretical analysis correspondingly. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.B21C1970B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.B21C1970B">Modeling the Space-Time Destiny of Pan-Arctic Permafrost DOC in a Global Land Surface Model: Feedback Implications</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Bowring, S.; Lauerwald, R.; Guenet, B.; Zhu, D.; Ciais, P. 2017-12-01 Most global climate models do not represent the unique permafrost soil environment and its respective processes. This significantly contributes to uncertainty in estimating their responses, and that of the planet at large, to warming. Here, the production, transport and atmospheric release of dissolved organic carbon (DOC) from high-latitude permafrost soils into inland waters and the ocean is explicitly represented for the first time in the land surface component (ORCHIDEE-MICT) of a CMIP6 global climate model (IPSL). This work merges two models that are able to mechanistically simulate complex processes for 1) snow, ice and soil phenomena in high latitude environments, and 2) DOC production and lateral transport through soils and the river network, respectively, at 0.5° to 2° resolution. The resulting model is subjected to a wide range of input forcing data, parameter testing and contentious feedback phenomena, including microbial heat generation as the active layer deepens. We present results for the present and future Pan-Arctic and Eurasia, with a focus on the Lena and Mackenzie River basins, and show that soil DOC concentrations, their riverine transport and atmospheric evasion are reasonably well represented as compared to observed stocks, fluxes and seasonality. We show that most basins exhibit large increases in DOC transport and riverine CO2 evasion across the suite of RCP scenarios to 2100. We also show that model output is strongly influenced by choice of input forcing data. The riverine component of what is known as the `boundless carbon cycle' is little-recognized in global climate modeling. Hydrological mobilization to the river network results either in sedimentary settling or atmospheric `evasion', presently amounting to 0.5-1.8 PgC yr-1. Our work aims at filling in these knowledge gaps, and the response of these DOC-related processes to thermal forcing. Potential feedbacks owing to such a response are of particular relevance, given the magnitude </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28140727','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28140727">Relational interaction in occupational therapy: Conversation analysis of positive feedback.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Weiste, Elina 2018-01-01 The therapeutic relationship is an important factor for good therapy outcomes. The primary mediator of a beneficial therapy relationship is clinician-client interaction. However, few studies identify the observable interactional attributes of good quality relational interactions, e.g. offering the client positive feedback. The present paper aims to expand current understanding of relational interaction by analyzing the real-time interactional practices therapists use for offering positive feedback, an important value in occupational therapy. The analysis is based on the conversation analysis of 15 video-recorded occupational therapy encounters in psychiatric outpatient clinics. Two types of positive feedback were identified. In aligning feedback, therapists encouraged and complimented clients' positive perspectives on their own achievements in adopting certain behaviour, encouraging and supporting their progress. In redirecting feedback, therapists shifted the perspective from clients' negative experiences to their positive experiences. This shift was interactionally successful if they laid the foundation for the shift in perspective and attuned their expressions to the clients' emotional states. Occupational therapists routinely provide their clients with positive feedback. Awareness of the interactional attributes related to positive feedback is critically important for successful relational interaction. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18823521','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18823521">Specialty-specific multi-source feedback: assuring validity, informing training.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Davies, Helena; Archer, Julian; Bateman, Adrian; Dewar, Sandra; Crossley, Jim; Grant, Janet; Southgate, Lesley 2008-10-01 The white paper 'Trust, Assurance and Safety: the Regulation of Health Professionals in the 21st Century' proposes a single, generic multi-source feedback (MSF) instrument in the UK. Multi-source feedback was proposed as part of the assessment programme for Year 1 specialty training in histopathology. An existing instrument was modified following blueprinting against the histopathology curriculum to establish content validity. Trainees were also assessed using an objective structured practical examination (OSPE). Factor analysis and correlation between trainees' OSPE performance and the MSF were used to explore validity. All 92 trainees participated and the assessor response rate was 93%. Reliability was acceptable with eight assessors (95% confidence interval 0.38). Factor analysis revealed two factors: 'generic' and 'histopathology'. Pearson correlation of MSF scores with OSPE performances was 0.48 (P = 0.001) and the histopathology factor correlated more highly (histopathology r = 0.54, generic r = 0.42; t = - 2.76, d.f. = 89, P < 0.01). Trainees scored least highly in relation to ability to use histopathology to solve clinical problems (mean = 4.39) and provision of good reports (mean = 4.39). Three of six doctors whose means were < 4.0 received free text comments about report writing. There were 83 forms with aggregate scores of < 4. Of these, 19.2% included comments about report writing. Specialty-specific MSF is feasible and achieves satisfactory reliability. The higher correlation of the 'histopathology' factor with the OSPE supports validity. This paper highlights the importance of validating an MSF instrument within the specialty-specific context as, in addition to assuring content validity, the PATH-SPRAT (Histopathology-Sheffield Peer Review Assessment Tool) also demonstrates the potential to inform training as part of a quality improvement model. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.A12C..01S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.A12C..01S">On the Representation of Ice Nucleation in Global Climate Models, and its Importance for Simulations of Climate Forcings and Feedbacks</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Storelvmo, T. 2015-12-01 Substantial improvements have been made to the cloud microphysical schemes used in the latest generation of global climate models (GCMs), however, an outstanding weakness of these schemes lies in the arbitrariness of their tuning parameters. Despite the growing effort in improving the cloud microphysical schemes in GCMs, most of this effort has not focused on improving the ability of GCMs to accurately simulate phase partitioning in mixed-phase clouds. Getting the relative proportion of liquid droplets and ice crystals in clouds right in GCMs is critical for the representation of cloud radiative forcings and cloud-climate feedbacks. Here, we first present satellite observations of cloud phase obtained by NASA's CALIOP instrument, and report on robust statistical relationships between cloud phase and several aerosols species that have been demonstrated to act as ice nuclei (IN) in laboratory studies. We then report on results from model intercomparison projects that reveal that GCMs generally underestimate the amount of supercooled liquid in clouds. For a selected GCM (NCAR 's CAM5), we thereafter show that the underestimate can be attributed to two main factors: i) the presence of IN in the mixed-phase temperature range, and ii) the Wegener-Bergeron-Findeisen process, which converts liquid to ice once ice crystals have formed. Finally, we show that adjusting these two processes such that the GCM's cloud phase is in agreement with the observed has a substantial impact on the simulated radiative forcing due to IN perturbations, as well as on the cloud-climate feedbacks and ultimately climate sensitivity simulated by the GCM. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFMNG43B1422M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFMNG43B1422M">Transient and asymptotic behavior in a regular network model for the ice-albedo feedback under thermal forcing</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Mueller-Stoffels, M.; Wackerbauer, R. 2010-12-01 The Arctic ocean and sea ice form a feedback system which plays an important role in the global climate. Variations of the global ice and snow distribution have a significant effect on the planetary albedo which governs the absorption of shortwave radiation. The complexity of highly parametrized GCMs makes it very difficult to assess single feedback processes in the climate system without the concurrent use of simple models where the physics are understood [1][2][3]. We introduce a complex systems model to investigate thermodynamic feedback processes in an Arctic ice-ocean layer. The ice-ocean layer is represented as a regular network of coupled cells. The state of each cell is determined by its energy content, which also defines the phase of the cell. The energy transport between cells is described with nonlinear and heterogeneous diffusion constants. And the time-evolution of the ice-ocean is driven by shortwave, longwave and lateral oceanic and atmospheric thermal forcing. This model is designed to study the stability of an ice cover under various heat intake scenarios. The network structure of the model allows to easily introduce albedo heterogeneities due to aging ice, wind blown snow cover, and ice movement to explore the time-evolution and pattern formation (melt ponds) processes in the Arctic sea ice. The solely thermodynamic model exhibits two stable states; one in the perennially ice covered domain and one in the perennially open water domain. Their existence is due to the temperature dependence of the longwave radiative budget. Transition between these states can be forced via lateral heat fluxes. During the transition from the ice covered to the open water stable state the ice albedo feedback effects are manifested as an increased warming rate of the ice cover together with enhanced seasonal energy oscillations. In the current model realization seasonal ice cover is present as a transient state only. Furthermore, the model exhibits hysteresis between </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24910596','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24910596">Corticocortical feedback increases the spatial extent of normalization.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Nassi, Jonathan J; Gómez-Laberge, Camille; Kreiman, Gabriel; Born, Richard T 2014-01-01 Normalization has been proposed as a canonical computation operating across different brain regions, sensory modalities, and species. It provides a good phenomenological description of non-linear response properties in primary visual cortex (V1), including the contrast response function and surround suppression. Despite its widespread application throughout the visual system, the underlying neural mechanisms remain largely unknown. We recently observed that corticocortical feedback contributes to surround suppression in V1, raising the possibility that feedback acts through normalization. To test this idea, we characterized area summation and contrast response properties in V1 with and without feedback from V2 and V3 in alert macaques and applied a standard normalization model to the data. Area summation properties were well explained by a form of divisive normalization, which computes the ratio between a neuron's driving input and the spatially integrated activity of a "normalization pool." Feedback inactivation reduced surround suppression by shrinking the spatial extent of the normalization pool. This effect was independent of the gain modulation thought to mediate the influence of contrast on area summation, which remained intact during feedback inactivation. Contrast sensitivity within the receptive field center was also unaffected by feedback inactivation, providing further evidence that feedback participates in normalization independent of the circuit mechanisms involved in modulating contrast gain and saturation. These results suggest that corticocortical feedback contributes to surround suppression by increasing the visuotopic extent of normalization and, via this mechanism, feedback can play a critical role in contextual information processing. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3123842','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3123842">Adaptive Control Model Reveals Systematic Feedback and Key Molecules in Metabolic Pathway Regulation</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Moffitt, Richard A.; Merrill, Alfred H.; Wang, May D. 2011-01-01 Abstract Robust behavior in metabolic pathways resembles stabilized performance in systems under autonomous control. This suggests we can apply control theory to study existing regulation in these cellular networks. Here, we use model-reference adaptive control (MRAC) to investigate the dynamics of de novo sphingolipid synthesis regulation in a combined theoretical and experimental case study. The effects of serine palmitoyltransferase over-expression on this pathway are studied in vitro using human embryonic kidney cells. We report two key results from comparing numerical simulations with observed data. First, MRAC simulations of pathway dynamics are comparable to simulations from a standard model using mass action kinetics. The root-sum-square (RSS) between data and simulations in both cases differ by less than 5%. Second, MRAC simulations suggest systematic pathway regulation in terms of adaptive feedback from individual molecules. In response to increased metabolite levels available for de novo sphingolipid synthesis, feedback from molecules along the main artery of the pathway is regulated more frequently and with greater amplitude than from other molecules along the branches. These biological insights are consistent with current knowledge while being new that they may guide future research in sphingolipid biology. In summary, we report a novel approach to study regulation in cellular networks by applying control theory in the context of robust metabolic pathways. We do this to uncover potential insight into the dynamics of regulation and the reverse engineering of cellular networks for systems biology. This new modeling approach and the implementation routines designed for this case study may be extended to other systems. Supplementary Material is available at www.liebertonline.com/cmb. PMID:21314456 </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JPhCS.574a2137T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JPhCS.574a2137T">Feedback stabilization of an oscillating vertical cylinder by POD Reduced-Order Model</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Tissot, Gilles; Cordier, Laurent; Noack, Bernd R. 2015-01-01 The objective is to demonstrate the use of reduced-order models (ROM) based on proper orthogonal decomposition (POD) to stabilize the flow over a vertically oscillating circular cylinder in the laminar regime (Reynolds number equal to 60). The 2D Navier-Stokes equations are first solved with a finite element method, in which the moving cylinder is introduced via an ALE method. Since in fluid-structure interaction, the POD algorithm cannot be applied directly, we implemented the fictitious domain method of Glowinski et al. [1] where the solid domain is treated as a fluid undergoing an additional constraint. The POD-ROM is classically obtained by projecting the Navier-Stokes equations onto the first POD modes. At this level, the cylinder displacement is enforced in the POD-ROM through the introduction of Lagrange multipliers. For determining the optimal vertical velocity of the cylinder, a linear quadratic regulator framework is employed. After linearization of the POD-ROM around the steady flow state, the optimal linear feedback gain is obtained as solution of a generalized algebraic Riccati equation. Finally, when the optimal feedback control is applied, it is shown that the flow converges rapidly to the steady state. In addition, a vanishing control is obtained proving the efficiency of the control approach. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhyA..465...91S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhyA..465...91S">Extended nonlinear feedback model for describing episodes of high inflation</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Szybisz, Martín A.; Szybisz, Leszek 2017-01-01 An extension of the nonlinear feedback (NLF) formalism to describe regimes of hyper- and high-inflation in economy is proposed in the present work. In the NLF model the consumer price index (CPI) exhibits a finite time singularity of the type 1 /(tc - t) (1 - β) / β, with β > 0, predicting a blow up of the economy at a critical time tc. However, this model fails in determining tc in the case of weak hyperinflation regimes like, e.g., that occurred in Israel. To overcome this trouble, the NLF model is extended by introducing a parameter γ, which multiplies all terms with past growth rate index (GRI). In this novel approach the solution for CPI is also analytic being proportional to the Gaussian hypergeometric function 2F1(1 / β , 1 / β , 1 + 1 / β ; z) , where z is a function of β, γ, and tc. For z → 1 this hypergeometric function diverges leading to a finite time singularity, from which a value of tc can be determined. This singularity is also present in GRI. It is shown that the interplay between parameters β and γ may produce phenomena of multiple equilibria. An analysis of the severe hyperinflation occurred in Hungary proves that the novel model is robust. When this model is used for examining data of Israel a reasonable tc is got. High-inflation regimes in Mexico and Iceland, which exhibit weaker inflations than that of Israel, are also successfully described. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4304240','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4304240">Effects of different feedback types on information integration in repeated monetary gambles</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Haffke, Peter; Hübner, Ronald 2015-01-01 Most models of risky decision making assume that all relevant information is taken into account (e.g., von Neumann and Morgenstern, 1944; Kahneman and Tversky, 1979). However, there are also some models supposing that only part of the information is considered (e.g., Brandstätter et al., 2006; Gigerenzer and Gaissmaier, 2011). To further investigate the amount of information that is usually used for decision making, and how the use depends on feedback, we conducted a series of three experiments in which participants choose between two lotteries and where no feedback, outcome feedback, and error feedback was provided, respectively. The results show that without feedback participants mostly chose the lottery with the higher winning probability, and largely ignored the potential gains. The same results occurred when the outcome of each decision was fed back. Only after presenting error feedback (i.e., signaling whether a choice was optimal or not), participants considered probabilities as well as gains, resulting in more optimal choices. We propose that outcome feedback was ineffective, because of its probabilistic and ambiguous nature. Participants improve information integration only if provided with a consistent and deterministic signal such as error feedback. PMID:25667576 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25667576','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25667576">Effects of different feedback types on information integration in repeated monetary gambles.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Haffke, Peter; Hübner, Ronald 2014-01-01 Most models of risky decision making assume that all relevant information is taken into account (e.g., von Neumann and Morgenstern, 1944; Kahneman and Tversky, 1979). However, there are also some models supposing that only part of the information is considered (e.g., Brandstätter et al., 2006; Gigerenzer and Gaissmaier, 2011). To further investigate the amount of information that is usually used for decision making, and how the use depends on feedback, we conducted a series of three experiments in which participants choose between two lotteries and where no feedback, outcome feedback, and error feedback was provided, respectively. The results show that without feedback participants mostly chose the lottery with the higher winning probability, and largely ignored the potential gains. The same results occurred when the outcome of each decision was fed back. Only after presenting error feedback (i.e., signaling whether a choice was optimal or not), participants considered probabilities as well as gains, resulting in more optimal choices. We propose that outcome feedback was ineffective, because of its probabilistic and ambiguous nature. Participants improve information integration only if provided with a consistent and deterministic signal such as error feedback. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29467687','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29467687">"Homework Feedback Is…": Elementary and Middle School Teachers' Conceptions of Homework Feedback.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Cunha, Jennifer; Rosário, Pedro; Núñez, José Carlos; Nunes, Ana Rita; Moreira, Tânia; Nunes, Tânia 2018-01-01 This study explored mathematics teachers' conceptions of the homework feedback focusing on four key aspects: definition, purpose, types, and perceived impact. Forty-seven teachers from elementary and middle schools participated in six focus groups. Data were analyzed using content analysis. To enhance the trustworthiness of findings, classroom observations were used for triangulation of data. Participants conceptualized homework feedback in three directions (i.e., teachers' feedback provided to students, students' feedback provided to teachers, and homework self-feedback), being teachers' monitoring of students' learning the purpose reported by most teachers. Participants also reported the types of homework feedback more frequently used in class (e.g., checking homework completion, checking homework on the board), and their perceived impact on students. Findings provide valuable information to deepen the understanding of the homework feedback process, which may help develop new avenues for future research. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=cybernetics&pg=5&id=EJ536187','ERIC'); return false;" href="https://eric.ed.gov/?q=cybernetics&pg=5&id=EJ536187">Feedback in Information Retrieval.</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Spink, Amanda; Losee, Robert M. 1996-01-01 As Information Retrieval (IR) has evolved, it has become a highly interactive process, rooted in cognitive and situational contexts. Consequently the traditional cybernetic-based IR model does not suffice for interactive IR or the human approach to IR. Reviews different views of feedback in IR and their relationship to cybernetic and social… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24343906','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24343906">Climate warming feedback from mountain birch forest expansion: reduced albedo dominates carbon uptake.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> de Wit, Heleen A; Bryn, Anders; Hofgaard, Annika; Karstensen, Jonas; Kvalevåg, Maria M; Peters, Glen P 2014-07-01 Expanding high-elevation and high-latitude forest has contrasting climate feedbacks through carbon sequestration (cooling) and reduced surface reflectance (warming), which are yet poorly quantified. Here, we present an empirically based projection of mountain birch forest expansion in south-central Norway under climate change and absence of land use. Climate effects of carbon sequestration and albedo change are compared using four emission metrics. Forest expansion was modeled for a projected 2.6 °C increase in summer temperature in 2100, with associated reduced snow cover. We find that the current (year 2000) forest line of the region is circa 100 m lower than its climatic potential due to land-use history. In the future scenarios, forest cover increased from 12% to 27% between 2000 and 2100, resulting in a 59% increase in biomass carbon storage and an albedo change from 0.46 to 0.30. Forest expansion in 2100 was behind its climatic potential, forest migration rates being the primary limiting factor. In 2100, the warming caused by lower albedo from expanding forest was 10 to 17 times stronger than the cooling effect from carbon sequestration for all emission metrics considered. Reduced snow cover further exacerbated the net warming feedback. The warming effect is considerably stronger than previously reported for boreal forest cover, because of the typically low biomass density in mountain forests and the large changes in albedo of snow-covered tundra areas. The positive climate feedback of high-latitude and high-elevation expanding forests with seasonal snow cover exceeds those of afforestation at lower elevation, and calls for further attention of both modelers and empiricists. The inclusion and upscaling of these climate feedbacks from mountain forests into global models is warranted to assess the potential global impacts. © 2013 John Wiley & Sons Ltd. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017SuScT..30f4006G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017SuScT..30f4006G">Electrothermal feedback in kinetic inductance detectors</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Guruswamy, T.; Thomas, C. N.; Withington, S.; Goldie, D. J. 2017-06-01 In kinetic inductance detectors (KIDs) and other similar applications of superconducting microresonators, both the large and small-signal behaviour of the device may be affected by electrothermal feedback. Microwave power applied to read out the device is absorbed by and heats the superconductor quasiparticles, changing the superconductor conductivity and hence the readout power absorbed in a positive or negative feedback loop. In this work, we explore numerically the implications of an extensible theoretical model of a generic superconducting microresonator device for a typical KID, incorporating recent work on the power flow between superconductor quasiparticles and phonons. This model calculates the large-signal (changes in operating point) and small-signal behaviour of a device, allowing us to determine the effect of electrothermal feedback on device responsivity and noise characteristics under various operating conditions. We also investigate how thermally isolating the device from the bath, for example by designing the device on a membrane only connected to the bulk substrate by thin legs, affects device performance. We find that at a typical device operating point, positive electrothermal feedback reduces the effective thermal conductance from the superconductor quasiparticles to the bath, and so increases responsivity to signal (pair-breaking) power, increases noise from temperature fluctuations, and decreases the noise equivalent power (NEP). Similarly, increasing the thermal isolation of the device while keeping the quasiparticle temperature constant decreases the NEP, but also decreases the device response bandwidth. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19990008647','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19990008647">Predictive Feedback and Feedforward Control for Systems with Unknown Disturbances</a> <a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a> Juang, Jer-Nan; Eure, Kenneth W. 1998-01-01 Predictive feedback control has been successfully used in the regulation of plate vibrations when no reference signal is available for feedforward control. However, if a reference signal is available it may be used to enhance regulation by incorporating a feedforward path in the feedback controller. Such a controller is known as a hybrid controller. This paper presents the theory and implementation of the hybrid controller for general linear systems, in particular for structural vibration induced by acoustic noise. The generalized predictive control is extended to include a feedforward path in the multi-input multi-output case and implemented on a single-input single-output test plant to achieve plate vibration regulation. There are cases in acoustic-induce vibration where the disturbance signal is not available to be used by the hybrid controller, but a disturbance model is available. In this case the disturbance model may be used in the feedback controller to enhance performance. In practice, however, neither the disturbance signal nor the disturbance model is available. This paper presents the theory of identifying and incorporating the noise model into the feedback controller. Implementations are performed on a test plant and regulation improvements over the case where no noise model is used are demonstrated. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70035148','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70035148">Strong atmospheric chemistry feedback to climate warming from Arctic methane emissions</a> <a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a> Isaksen, Ivar S.A.; Gauss, Michael; Myhre, Gunnar; Walter Anthony, Katey M.; Ruppel, Carolyn 2011-01-01 The magnitude and feedbacks of future methane release from the Arctic region are unknown. Despite limited documentation of potential future releases associated with thawing permafrost and degassing methane hydrates, the large potential for future methane releases calls for improved understanding of the interaction of a changing climate with processes in the Arctic and chemical feedbacks in the atmosphere. Here we apply a “state of the art” atmospheric chemistry transport model to show that large emissions of CH4 would likely have an unexpectedly large impact on the chemical composition of the atmosphere and on radiative forcing (RF). The indirect contribution to RF of additional methane emission is particularly important. It is shown that if global methane emissions were to increase by factors of 2.5 and 5.2 above current emissions, the indirect contributions to RF would be about 250% and 400%, respectively, of the RF that can be attributed to directly emitted methane alone. Assuming several hypothetical scenarios of CH4 release associated with permafrost thaw, shallow marine hydrate degassing, and submarine landslides, we find a strong positive feedback on RF through atmospheric chemistry. In particular, the impact of CH4 is enhanced through increase of its lifetime, and of atmospheric abundances of ozone, stratospheric water vapor, and CO2 as a result of atmospheric chemical processes. Despite uncertainties in emission scenarios, our results provide a better understanding of the feedbacks in the atmospheric chemistry that would amplify climate warming. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22194574','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22194574">Evidence from numerical experiments for a feedback dynamo generating Mercury's magnetic field.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Heyner, Daniel; Wicht, Johannes; Gómez-Pérez, Natalia; Schmitt, Dieter; Auster, Hans-Ulrich; Glassmeier, Karl-Heinz 2011-12-23 The observed weakness of Mercury's magnetic field poses a long-standing puzzle to dynamo theory. Using numerical dynamo simulations, we show that it could be explained by a negative feedback between the magnetospheric and the internal magnetic fields. Without feedback, a small internal field was amplified by the dynamo process up to Earth-like values. With feedback, the field strength saturated at a much lower level, compatible with the observations at Mercury. The classical saturation mechanism via the Lorentz force was replaced by the external field impact. The resulting surface field was dominated by uneven harmonic components. This will allow the feedback model to be distinguished from other models once a more accurate field model is constructed from MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) and BepiColombo data. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4009509','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4009509">Accuracy and speed feedback: Global and local effects on strategy use</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Touron, Dayna R.; Hertzog, Christopher 2013-01-01 Background Skill acquisition often involves a shift from an effortful algorithm-based strategy to more fluent memory-based performance. Older adults’ slower strategy transitions can be ascribed to both slowed learning and metacognitive factors. Experimenters often provide feedback on response accuracy; this emphasis may either inadvertently reinforce older adults’ conservatism or might highlight that retrieval is generally quite accurate. RT feedback can lead to more rapid shift to retrieval (Hertzog, Touron, & Hines, 2007). Methods This study parametrically varied trial-by-trial feedback to examine whether strategy shifts in the noun-pair task in younger (M = 19) and older adults (M = 67) were influenced by type of performance feedback: none, trial accuracy, trial RT, or both accuracy and RT. Results Older adults who received accuracy feedback retrieved more often, particularly on difficult rearranged trials, and participants who receive speed feedback performed the scanning strategy more quickly. Age differences were also obtained in local (trial-level) reactivity to task performance, but these were not affected by feedback. Conclusions Accuracy and speed feedback had distinct global (general) influences on task strategies and performance. In particular, it appears that the standard practice of providing trial-by-trial accuracy feedback might facilitate older adults’ use of retrieval strategies in skill acquisition tasks. PMID:24785594 </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active">23</li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active">24</li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16475782','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16475782">A global bioheat model with self-tuning optimal regulation of body temperature using Hebbian feedback covariance learning.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Ong, M L; Ng, E Y K 2005-12-01 In the lower brain, body temperature is continually being regulated almost flawlessly despite huge fluctuations in ambient and physiological conditions that constantly threaten the well-being of the body. The underlying control problem defining thermal homeostasis is one of great enormity: Many systems and sub-systems are involved in temperature regulation and physiological processes are intrinsically complex and intertwined. Thus the defining control system has to take into account the complications of nonlinearities, system uncertainties, delayed feedback loops as well as internal and external disturbances. In this paper, we propose a self-tuning adaptive thermal controller based upon Hebbian feedback covariance learning where the system is to be regulated continually to best suit its environment. This hypothesis is supported in part by postulations of the presence of adaptive optimization behavior in biological systems of certain organisms which face limited resources vital for survival. We demonstrate the use of Hebbian feedback covariance learning as a possible self-adaptive controller in body temperature regulation. The model postulates an important role of Hebbian covariance adaptation as a means of reinforcement learning in the thermal controller. The passive system is based on a simplified 2-node core and shell representation of the body, where global responses are captured. Model predictions are consistent with observed thermoregulatory responses to conditions of exercise and rest, and heat and cold stress. An important implication of the model is that optimal physiological behaviors arising from self-tuning adaptive regulation in the thermal controller may be responsible for the departure from homeostasis in abnormal states, e.g., fever. This was previously unexplained using the conventional "set-point" control theory. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28283576','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28283576">Glucocorticoid and cytokine crosstalk: Feedback, feedforward, and co-regulatory interactions determine repression or resistance.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Newton, Robert; Shah, Suharsh; Altonsy, Mohammed O; Gerber, Antony N 2017-04-28 Inflammatory signals induce feedback and feedforward systems that provide temporal control. Although glucocorticoids can repress inflammatory gene expression, glucocorticoid receptor recruitment increases expression of negative feedback and feedforward regulators, including the phosphatase, DUSP1, the ubiquitin-modifying enzyme, TNFAIP3, or the mRNA-destabilizing protein, ZFP36. Moreover, glucocorticoid receptor cooperativity with factors, including nuclear factor-κB (NF-κB), may enhance regulator expression to promote repression. Conversely, MAPKs, which are inhibited by glucocorticoids, provide feedforward control to limit expression of the transcription factor IRF1, and the chemokine, CXCL10. We propose that modulation of feedback and feedforward control can determine repression or resistance of inflammatory gene expression toglucocorticoid. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26497268','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26497268">Randomised prior feedback modulates neural signals of outcome monitoring.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Mushtaq, Faisal; Wilkie, Richard M; Mon-Williams, Mark A; Schaefer, Alexandre 2016-01-15 Substantial evidence indicates that decision outcomes are typically evaluated relative to expectations learned from relatively long sequences of previous outcomes. This mechanism is thought to play a key role in general learning and adaptation processes but relatively little is known about the determinants of outcome evaluation when the capacity to learn from series of prior events is difficult or impossible. To investigate this issue, we examined how the feedback-related negativity (FRN) is modulated by information briefly presented before outcome evaluation. The FRN is a brain potential time-locked to the delivery of decision feedback and it is widely thought to be sensitive to prior expectations. We conducted a multi-trial gambling task in which outcomes at each trial were fully randomised to minimise the capacity to learn from long sequences of prior outcomes. Event-related potentials for outcomes (Win/Loss) in the current trial (Outcomet) were separated according to the type of outcomes that occurred in the preceding two trials (Outcomet-1 and Outcomet-2). We found that FRN voltage was more positive during the processing of win feedback when it was preceded by wins at Outcomet-1 compared to win feedback preceded by losses at Outcomet-1. However, no influence of preceding outcomes was found on FRN activity relative to the processing of loss feedback. We also found no effects of Outcomet-2 on FRN amplitude relative to current feedback. Additional analyses indicated that this effect was largest for trials in which participants selected a decision different to the gamble chosen in the previous trial. These findings are inconsistent with models that solely relate the FRN to prediction error computation. Instead, our results suggest that if stable predictions about future events are weak or non-existent, then outcome processing can be determined by affective systems. More specifically, our results indicate that the FRN is likely to reflect the activity of positive </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4692517','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4692517">Randomised prior feedback modulates neural signals of outcome monitoring</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Mushtaq, Faisal; Wilkie, Richard M.; Mon-Williams, Mark A.; Schaefer, Alexandre 2016-01-01 Substantial evidence indicates that decision outcomes are typically evaluated relative to expectations learned from relatively long sequences of previous outcomes. This mechanism is thought to play a key role in general learning and adaptation processes but relatively little is known about the determinants of outcome evaluation when the capacity to learn from series of prior events is difficult or impossible. To investigate this issue, we examined how the feedback-related negativity (FRN) is modulated by information briefly presented before outcome evaluation. The FRN is a brain potential time-locked to the delivery of decision feedback and it is widely thought to be sensitive to prior expectations. We conducted a multi-trial gambling task in which outcomes at each trial were fully randomised to minimise the capacity to learn from long sequences of prior outcomes. Event-related potentials for outcomes (Win/Loss) in the current trial (Outcomet) were separated according to the type of outcomes that occurred in the preceding two trials (Outcomet-1 and Outcomet-2). We found that FRN voltage was more positive during the processing of win feedback when it was preceded by wins at Outcomet-1 compared to win feedback preceded by losses at Outcomet-1. However, no influence of preceding outcomes was found on FRN activity relative to the processing of loss feedback. We also found no effects of Outcomet-2 on FRN amplitude relative to current feedback. Additional analyses indicated that this effect was largest for trials in which participants selected a decision different to the gamble chosen in the previous trial. These findings are inconsistent with models that solely relate the FRN to prediction error computation. Instead, our results suggest that if stable predictions about future events are weak or non-existent, then outcome processing can be determined by affective systems. More specifically, our results indicate that the FRN is likely to reflect the activity of positive </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/12687924','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/12687924">Fear of feedback.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Jackman, Jay M; Strober, Myra H 2003-04-01 Nobody likes performance reviews. Subordinates are terrified they'll hear nothing but criticism. Bosses think their direct reports will respond to even the mildest criticism with anger or tears. The result? Everyone keeps quiet. That's unfortunate, because most people need help figuring out how to improve their performance and advance their careers. This fear of feedback doesn't come into play just during annual reviews. At least half the executives with whom the authors have worked never ask for feedback. Many expect the worst: heated arguments, even threats of dismissal. So rather than seek feedback, people try to guess what their bosses are thinking. Fears and assumptions about feedback often manifest themselves in psychologically maladaptive behaviors such as procrastination, denial, brooding, jealousy, and self-sabotage. But there's hope, say the authors. Those who learn adaptive techniques can free themselves from destructive responses. They'll be able to deal with feedback better if they acknowledge negative emotions, reframe fear and criticism constructively, develop realistic goals, create support systems, and reward themselves for achievements along the way. Once you've begun to alter your maladaptive behaviors, you can begin seeking regular feedback from your boss. The authors take you through four steps for doing just that: self-assessment, external assessment, absorbing the feedback, and taking action toward change. Organizations profit when employees ask for feedback and deal well with criticism. Once people begin to know how they are doing relative to management's priorities, their work becomes better aligned with organizational goals. What's more, they begin to transform a feedback-averse environment into a more honest and open one, in turn improving performance throughout the organization. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=emotional+AND+response&pg=2&id=EJ1038652','ERIC'); return false;" href="https://eric.ed.gov/?q=emotional+AND+response&pg=2&id=EJ1038652">Understanding Classroom Feedback Practices: A Study of New Zealand Student Experiences, Perceptions, and Emotional Responses</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Harris, Lois R.; Brown, Gavin T.; Harnett, Jennifer A. 2014-01-01 While feedback is a key factor for improving student learning, little is known about how students understand and experience feedback within the classroom. This study analysed 193 New Zealand primary and secondary students' survey responses alongside drawings of their understandings and experiences of feedback to examine how they experience,… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3933776','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3933776">Feedback about action performed can alter the sense of self-agency</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Kumar, Neeraj; Manjaly, Jaison A.; Miyapuram, Krishna P. 2014-01-01 Sense of agency refers to the sense of authorship of an action and its outcome. Sense of agency is often explained through computational models of motor control (e.g., the comparator model). Previous studies using the comparator model have manipulated action-outcome contingency to understand its effect on the sense of agency. More recent studies have shown that cues related to outcome, priming outcome and priming action have an effect on agency attribution. However, relatively few studies have focused on the effect of recalibrating internal predictions on the sense of agency. This study aims to investigate how feedback about action can recalibrate prediction and modulates the sense of agency. While participants performed a Flanker task, we manipulated the feedback about the validity of the action performed, independent of their responses. When true feedback is given, the sense of agency would reflect congruency between the sensory outcome and the action performed. The results show an opposite effect on the sense of agency when false feedback was given. We propose that feedback about action performed can recalibrate the prediction of sensory outcome and thus alter the sense of agency. PMID:24611059 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23543746','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23543746">Feedback Seeking in Early Adolescence: Self-Enhancement or Self-Verification?</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Rosen, Lisa H; Principe, Connor P; Langlois, Judith H 2013-02-13 The authors examined whether early adolescents ( N = 90) solicit self-enhancing feedback (i.e., positive feedback) or self-verifying feedback (i.e., feedback congruent with self-views, even when these views are negative). Sixth, seventh, and eighth graders first completed a self-perception measure and then selected whether to receive positive or negative feedback from an unknown peer in different domains of self. Results were consistent with self-verification theory; adolescents who perceived themselves as having both strengths and weaknesses were more likely to seek negative feedback regarding a self-perceived weakness compared to a self-perceived strength. The authors found similar support for self-verification processes when they considered the entire sample regardless of perceived strengths and weaknesses; hierarchical linear modeling (HLM) examined the predictive power of ratings of self-perceived ability, certainty, and importance on feedback seeking for all participants and provided additional evidence of self-verification strivings in adolescence. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3610180','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3610180">Feedback Seeking in Early Adolescence: Self-Enhancement or Self-Verification?</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Rosen, Lisa H.; Principe, Connor P.; Langlois, Judith H. 2012-01-01 The authors examined whether early adolescents (N = 90) solicit self-enhancing feedback (i.e., positive feedback) or self-verifying feedback (i.e., feedback congruent with self-views, even when these views are negative). Sixth, seventh, and eighth graders first completed a self-perception measure and then selected whether to receive positive or negative feedback from an unknown peer in different domains of self. Results were consistent with self-verification theory; adolescents who perceived themselves as having both strengths and weaknesses were more likely to seek negative feedback regarding a self-perceived weakness compared to a self-perceived strength. The authors found similar support for self-verification processes when they considered the entire sample regardless of perceived strengths and weaknesses; hierarchical linear modeling (HLM) examined the predictive power of ratings of self-perceived ability, certainty, and importance on feedback seeking for all participants and provided additional evidence of self-verification strivings in adolescence. PMID:23543746 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4732667','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4732667">Modelling Feedback Excitation, Pacemaker Properties and Sensory Switching of Electrically Coupled Brainstem Neurons Controlling Rhythmic Activity</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Hull, Michael J.; Soffe, Stephen R.; Willshaw, David J.; Roberts, Alan 2016-01-01 What cellular and network properties allow reliable neuronal rhythm generation or firing that can be started and stopped by brief synaptic inputs? We investigate rhythmic activity in an electrically-coupled population of brainstem neurons driving swimming locomotion in young frog tadpoles, and how activity is switched on and off by brief sensory stimulation. We build a computational model of 30 electrically-coupled conditional pacemaker neurons on one side of the tadpole hindbrain and spinal cord. Based on experimental estimates for neuron properties, population sizes, synapse strengths and connections, we show that: long-lasting, mutual, glutamatergic excitation between the neurons allows the network to sustain rhythmic pacemaker firing at swimming frequencies following brief synaptic excitation; activity persists but rhythm breaks down without electrical coupling; NMDA voltage-dependency doubles the range of synaptic feedback strengths generating sustained rhythm. The network can be switched on and off at short latency by brief synaptic excitation and inhibition. We demonstrate that a population of generic Hodgkin-Huxley type neurons coupled by glutamatergic excitatory feedback can generate sustained asynchronous firing switched on and off synaptically. We conclude that networks of neurons with NMDAR mediated feedback excitation can generate self-sustained activity following brief synaptic excitation. The frequency of activity is limited by the kinetics of the neuron membrane channels and can be stopped by brief inhibitory input. Network activity can be rhythmic at lower frequencies if the neurons are electrically coupled. Our key finding is that excitatory synaptic feedback within a population of neurons can produce switchable, stable, sustained firing without synaptic inhibition. PMID:26824331 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3216642','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3216642">Clustering in Cell Cycle Dynamics with General Response/Signaling Feedback</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Young, Todd R.; Fernandez, Bastien; Buckalew, Richard; Moses, Gregory; Boczko, Erik M. 2011-01-01 Motivated by experimental and theoretical work on autonomous oscillations in yeast, we analyze ordinary differential equations models of large populations of cells with cell-cycle dependent feedback. We assume a particular type of feedback that we call Responsive/Signaling (RS), but do not specify a functional form of the feedback. We study the dynamics and emergent behaviour of solutions, particularly temporal clustering and stability of clustered solutions. We establish the existence of certain periodic clustered solutions as well as “uniform” solutions and add to the evidence that cell-cycle dependent feedback robustly leads to cell-cycle clustering. We highlight the fundamental differences in dynamics between systems with negative and positive feedback. For positive feedback systems the most important mechanism seems to be the stability of individual isolated clusters. On the other hand we find that in negative feedback systems, clusters must interact with each other to reinforce coherence. We conclude from various details of the mathematical analysis that negative feedback is most consistent with observations in yeast experiments. PMID:22001733 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26186763','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26186763">Cutaneous Feedback of Fingertip Deformation and Vibration for Palpation in Robotic Surgery.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Pacchierotti, Claudio; Prattichizzo, Domenico; Kuchenbecker, Katherine J 2016-02-01 Despite its expected clinical benefits, current teleoperated surgical robots do not provide the surgeon with haptic feedback largely because grounded forces can destabilize the system's closed-loop controller. This paper presents an alternative approach that enables the surgeon to feel fingertip contact deformations and vibrations while guaranteeing the teleoperator's stability. We implemented our cutaneous feedback solution on an Intuitive Surgical da Vinci Standard robot by mounting a SynTouch BioTac tactile sensor to the distal end of a surgical instrument and a custom cutaneous display to the corresponding master controller. As the user probes the remote environment, the contact deformations, dc pressure, and ac pressure (vibrations) sensed by the BioTac are directly mapped to input commands for the cutaneous device's motors using a model-free algorithm based on look-up tables. The cutaneous display continually moves, tilts, and vibrates a flat plate at the operator's fingertip to optimally reproduce the tactile sensations experienced by the BioTac. We tested the proposed approach by having eighteen subjects use the augmented da Vinci robot to palpate a heart model with no haptic feedback, only deformation feedback, and deformation plus vibration feedback. Fingertip deformation feedback significantly improved palpation performance by reducing the task completion time, the pressure exerted on the heart model, and the subject's absolute error in detecting the orientation of the embedded plastic stick. Vibration feedback significantly improved palpation performance only for the seven subjects who dragged the BioTac across the model, rather than pressing straight into it. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AAS...22942301D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AAS...22942301D">How Supermassive Black Hole Feedback Might Work</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Donahue, Megan 2017-01-01 How black holes regulate their own growth and the growth of their host galaxy is an unsolved problem in galaxy evolution. The problem is particularly acute in the centers of clusters of galaxies, where the largest and most massive galaxies in the universe are found. That is, coincidentally, also where the interaction between the black hole and the surrounding gas is the easiest to study because the gas is sufficiently hot and dense to emit X-rays. The massive central galaxies of clusters of galaxies (BCGs) exhibit striking patterns in their relationships between star formation, radio AGN activity, and the thermodynamic state of the hot, X-ray emitting intracluster gas (ICM) surrounding the galaxies. The AGN jets excavate giant, kpc-scale cavities in the hot gas, in principle, supplying enough heat to the ICM to replace energy lost to radiative cooling. Simulations suggest (by elimination) that AGN feedback must be required to explain the luminosity and colors of these galaxies, but cosmological simulations still struggle with modeling how AGN feedback works in detail. In clusters of galaxies with active AGN and star-forming BCGs, the AGN somehow regulates the gaseous atmosphere to be marginally critical, with a ratio of the cooling time to the free fall time of ~ 5-20. This behavior is also seen in elliptical galaxies, where the feedback is mostly coming from stars. I will discuss the observations that motivated this model. The precipitation model in BCGs is a class of models known as "preventative" feedback, regulated by jets in BCGs. Further, the complex behaviour seen in recent idealized simulations seem to follow emergent patterns predicted by this model, while reproducing the scatter and the time scales inferred from the observations. The link between the thermal instabilities and the depth of the gravitational potential may explain scaling laws such as the black hole mass-velocity dispersion relation, the galaxy mass-metallicity relation and the baryonic </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4039070','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4039070">Corticocortical feedback increases the spatial extent of normalization</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Nassi, Jonathan J.; Gómez-Laberge, Camille; Kreiman, Gabriel; Born, Richard T. 2014-01-01 Normalization has been proposed as a canonical computation operating across different brain regions, sensory modalities, and species. It provides a good phenomenological description of non-linear response properties in primary visual cortex (V1), including the contrast response function and surround suppression. Despite its widespread application throughout the visual system, the underlying neural mechanisms remain largely unknown. We recently observed that corticocortical feedback contributes to surround suppression in V1, raising the possibility that feedback acts through normalization. To test this idea, we characterized area summation and contrast response properties in V1 with and without feedback from V2 and V3 in alert macaques and applied a standard normalization model to the data. Area summation properties were well explained by a form of divisive normalization, which computes the ratio between a neuron's driving input and the spatially integrated activity of a “normalization pool.” Feedback inactivation reduced surround suppression by shrinking the spatial extent of the normalization pool. This effect was independent of the gain modulation thought to mediate the influence of contrast on area summation, which remained intact during feedback inactivation. Contrast sensitivity within the receptive field center was also unaffected by feedback inactivation, providing further evidence that feedback participates in normalization independent of the circuit mechanisms involved in modulating contrast gain and saturation. These results suggest that corticocortical feedback contributes to surround suppression by increasing the visuotopic extent of normalization and, via this mechanism, feedback can play a critical role in contextual information processing. PMID:24910596 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22411103','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22411103">Feedback-related brain activity predicts learning from feedback in multiple-choice testing.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Ernst, Benjamin; Steinhauser, Marco 2012-06-01 Different event-related potentials (ERPs) have been shown to correlate with learning from feedback in decision-making tasks and with learning in explicit memory tasks. In the present study, we investigated which ERPs predict learning from corrective feedback in a multiple-choice test, which combines elements from both paradigms. Participants worked through sets of multiple-choice items of a Swahili-German vocabulary task. Whereas the initial presentation of an item required the participants to guess the answer, corrective feedback could be used to learn the correct response. Initial analyses revealed that corrective feedback elicited components related to reinforcement learning (FRN), as well as to explicit memory processing (P300) and attention (early frontal positivity). However, only the P300 and early frontal positivity were positively correlated with successful learning from corrective feedback, whereas the FRN was even larger when learning failed. These results suggest that learning from corrective feedback crucially relies on explicit memory processing and attentional orienting to corrective feedback, rather than on reinforcement learning. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.B23C0208K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.B23C0208K">Constraints on long-term carbon-climate feedbacks from spatially resolved CO2 growth rate fluctuations linked to temperature and precipitation</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Keppel-Aleks, G.; Hoffman, F. M. 2014-12-01 Feedbacks between the global carbon cycle and climate represent one of the largest uncertainties in climate prediction. A promising method for reducing uncertainty in predictions of carbon-climate feedbacks is based on identifying an "emergent constraint" that leverages correlations between mechanistically linked long-term feedbacks and short-term variations within the model ensemble. By applying contemporary observations to evaluate model skill in simulating short-term variations, we may be able to better assess the probability of simulated long-term feedbacks. We probed the constraint on long-term terrestrial carbon stocks provided by climate-driven fluctuations in the atmospheric CO2 growth rate at contemporary timescales. We considered the impact of both temperature and precipitation anomalies on terrestrial ecosystem exchange and further separated the direct influence of fire where possible. When we explicitly considered the role of atmospheric transport in smoothing the imprint of climate-driven flux anomalies on atmospheric CO2 patterns, we found that the extent of temporal averaging of both the observations and ESM output leads to estimates for the long-term climate sensitivity of tropical land carbon storage that are different by a factor of two. In the context of these results, we discuss strategies for applying emergent constraints for benchmarking biogeochemical feedbacks in ESMs. Specifically, our results underscore the importance of selecting appropriate observational benchmarks and, for future model intercomparison projects, outputting fields that most closely correspond to available observational datasets. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20831971','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20831971">Overreliance on auditory feedback may lead to sound/syllable repetitions: simulations of stuttering and fluency-inducing conditions with a neural model of speech production.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Civier, Oren; Tasko, Stephen M; Guenther, Frank H 2010-09-01 This paper investigates the hypothesis that stuttering may result in part from impaired readout of feedforward control of speech, which forces persons who stutter (PWS) to produce speech with a motor strategy that is weighted too much toward auditory feedback control. Over-reliance on feedback control leads to production errors which if they grow large enough, can cause the motor system to "reset" and repeat the current syllable. This hypothesis is investigated using computer simulations of a "neurally impaired" version of the DIVA model, a neural network model of speech acquisition and production. The model's outputs are compared to published acoustic data from PWS' fluent speech, and to combined acoustic and articulatory movement data collected from the dysfluent speech of one PWS. The simulations mimic the errors observed in the PWS subject's speech, as well as the repairs of these errors. Additional simulations were able to account for enhancements of fluency gained by slowed/prolonged speech and masking noise. Together these results support the hypothesis that many dysfluencies in stuttering are due to a bias away from feedforward control and toward feedback control. The reader will be able to (a) describe the contribution of auditory feedback control and feedforward control to normal and stuttered speech production, (b) summarize the neural modeling approach to speech production and its application to stuttering, and (c) explain how the DIVA model accounts for enhancements of fluency gained by slowed/prolonged speech and masking noise. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010IJSyS..41...17E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010IJSyS..41...17E">Modelling and analysis of gene regulatory network using feedback control theory</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> El-Samad, H.; Khammash, M. 2010-01-01 Molecular pathways are a part of a remarkable hierarchy of regulatory networks that operate at all levels of organisation. These regulatory networks are responsible for much of the biological complexity within the cell. The dynamic character of these pathways and the prevalence of feedback regulation strategies in their operation make them amenable to systematic mathematical analysis using the same tools that have been used with success in analysing and designing engineering control systems. In this article, we aim at establishing this strong connection through various examples where the behaviour exhibited by gene networks is explained in terms of their underlying control strategies. We complement our analysis by a survey of mathematical techniques commonly used to model gene regulatory networks and analyse their dynamic behaviour. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1816529B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1816529B">Slab Ocean El Niño atmospheric feedbacks in Coupled Climate Models and its relationship to the Recharge Oscillator</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Bayr, Tobias; Wengel, Christian; Latif, Mojib 2016-04-01 Dommenget (2010) found that El Niño-like variability, termed Slab Ocean El Niño, can exist in the absence of ocean dynamics and is driven by the interaction of the atmospheric surface heat fluxes and the heat content of the upper ocean. Further, Dommenget et al. (2014) report the Slab Ocean El Niño is not an artefact of the ECHAM5-AGCM coupled to a slab ocean model. In fact, atmospheric feedbacks crucial to the Slab Ocean El Niño can also be found in many state-of-the-art coupled climate models participating in CMIP3 and CMIP5, so that ENSO in many CMIP models can be understood as a mixed recharge oscillator/Slab Ocean El Niño mode. Here we show further analysis of the Slab Ocean El Niño atmospheric feedbacks in coupled models. The BCCR_CM2.0 climate model from the CMIP3 data base, which has a very large equatorial cold bias, has an El Niño that is mostly driven by Slab Ocean El Niño atmospheric feedbacks and is used as an example to describe Slab Ocean El Niño atmospheric feedbacks in a coupled model. In the BCCR_CM2.0, the ENSO-related variability in the 20°C isotherm (Z20), a measure of upper ocean heat content, is decoupled from the first mode of the seasonal cycle-related variability, while the two are coupled in observations, with ENSO being phase-locked to the seasonal cycle. Further analysis of the seasonal cycle in Z20 using SODA Ocean Reanalysis reveals two different regimes in the seasonal cycle along the equator: The first regime, to which ENSO is phase-locked, extends over the west and central equatorial Pacific and is driven by subsurface ocean dynamics. The second regime, extending in observations only over the cold tongue region, is driven by the seasonal cycle at the sea surface and is shifted by roughly six months relative to the first regime. In a series of experiments with the Kiel Climate Model (KCM) with different mean states due to tuning in the convection parameters, we can show that the strength of the equatorial cold bias and the </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27426914','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27426914">Feedback in surgical education.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> El Boghdady, Michael; Alijani, Afshin 2017-04-01 The positive effect of feedback has long been recognized in surgical education. Surgical educators convey feedback to improve the performance of the surgical trainees. We aimed to review the scientific classification and application of feedback in surgical education, and to propose possible future directions for research. A literature search was performed using Pubmed, OVID, CINAHL, Web of science, EMBASE, ERIC database and Google Scholar. The following search terms were used: 'feedback', 'feedback in medical education', 'feedback in medical training' and 'feedback in surgery'. The search was limited to articles in English. From 1157 citations, 12 books and 43 articles met the inclusion criteria and were selected for this review. Feedback comes in a variety of types and is an essential tool for learning and developing performance in surgical education. Different methods of feedback application are evolving and future work needs to concentrate on the value of each method as well as the role of new technologies in surgical education. Copyright © 2016 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland. Published by Elsevier Ltd. All rights reserved. </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active">24</li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div id="page_25" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active">25</li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="481"> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=formative+AND+variable&pg=3&id=EJ787077','ERIC'); return false;" href="https://eric.ed.gov/?q=formative+AND+variable&pg=3&id=EJ787077">Focus on Formative Feedback</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Shute, Valerie J. 2008-01-01 This article reviews the corpus of research on feedback, with a focus on formative feedback--defined as information communicated to the learner that is intended to modify his or her thinking or behavior to improve learning. According to researchers, formative feedback should be nonevaluative, supportive, timely, and specific. Formative feedback is… </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1998PhDT........44I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1998PhDT........44I">Feedback linearizing control of a MIMO power system</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Ilyes, Laszlo Prior research has demonstrated that either the mechanical or electrical subsystem of a synchronous electric generator may be controlled using single-input single-output (SISO) nonlinear feedback linearization. This research suggests a new approach which applies nonlinear feedback linearization to a multi-input multi-output (MIMO) model of the synchronous electric generator connected to an infinite bus load model. In this way, the electrical and mechanical subsystems may be linearized and simultaneously decoupled through the introduction of a pair of auxiliary inputs. This allows well known, linear, SISO control methods to be effectively applied to the resulting systems. The derivation of the feedback linearizing control law is presented in detail, including a discussion on the use of symbolic math processing as a development tool. The linearizing and decoupling properties of the control law are validated through simulation. And finally, the robustness of the control law is demonstrated. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017IJSEd..39.1648Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017IJSEd..39.1648Z">Investigating the impact of automated feedback on students' scientific argumentation</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Zhu, Mengxiao; Lee, Hee-Sun; Wang, Ting; Liu, Ou Lydia; Belur, Vinetha; Pallant, Amy 2017-08-01 This study investigates the role of automated scoring and feedback in supporting students' construction of written scientific arguments while learning about factors that affect climate change in the classroom. The automated scoring and feedback technology was integrated into an online module. Students' written scientific argumentation occurred when they responded to structured argumentation prompts. After submitting the open-ended responses, students received scores generated by a scoring engine and written feedback associated with the scores in real-time. Using the log data that recorded argumentation scores as well as argument submission and revisions activities, we answer three research questions. First, how students behaved after receiving the feedback; second, whether and how students' revisions improved their argumentation scores; and third, did item difficulties shift with the availability of the automated feedback. Results showed that the majority of students (77%) made revisions after receiving the feedback, and students with higher initial scores were more likely to revise their responses. Students who revised had significantly higher final scores than those who did not, and each revision was associated with an average increase of 0.55 on the final scores. Analysis on item difficulty shifts showed that written scientific argumentation became easier after students used the automated feedback. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED440621.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED440621.pdf">A Review of Literature on Formative Evaluation of Teachers through Mid-Term Student Feedback and How the Reiser and Dick Instructional Planning Model Can Enhance This Feedback.</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Hampton, Scott E. Research has shown that student mid-term feedback has significantly increased subsequent ratings of teacher effectiveness, student achievement, and student attitudes when the feedback results were accompanied by expert consultation. A gap in the literature is an instrument intended to provide specific feedback on systematic planning and delivery… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29746091','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29746091">A Framework for Engineering Stress Resilient Plants Using Genetic Feedback Control and Regulatory Network Rewiring.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Foo, Mathias; Gherman, Iulia; Zhang, Peijun; Bates, Declan G; Denby, Katherine J 2018-05-23 Crop disease leads to significant waste worldwide, both pre- and postharvest, with subsequent economic and sustainability consequences. Disease outcome is determined both by the plants' response to the pathogen and by the ability of the pathogen to suppress defense responses and manipulate the plant to enhance colonization. The defense response of a plant is characterized by significant transcriptional reprogramming mediated by underlying gene regulatory networks, and components of these networks are often targeted by attacking pathogens. Here, using gene expression data from Botrytis cinerea-infected Arabidopsis plants, we develop a systematic approach for mitigating the effects of pathogen-induced network perturbations, using the tools of synthetic biology. We employ network inference and system identification techniques to build an accurate model of an Arabidopsis defense subnetwork that contains key genes determining susceptibility of the plant to the pathogen attack. Once validated against time-series data, we use this model to design and test perturbation mitigation strategies based on the use of genetic feedback control. We show how a synthetic feedback controller can be designed to attenuate the effect of external perturbations on the transcription factor CHE in our subnetwork. We investigate and compare two approaches for implementing such a controller biologically-direct implementation of the genetic feedback controller, and rewiring the regulatory regions of multiple genes-to achieve the network motif required to implement the controller. Our results highlight the potential of combining feedback control theory with synthetic biology for engineering plants with enhanced resilience to environmental stress. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4116619','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4116619">Ten tips for receiving feedback effectively in clinical practice</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Algiraigri, Ali H. 2014-01-01 Background Despite being recognized as a fundamental part of the educational process and emphasized for several decades in medical education, the influence of the feedback process is still suboptimal. This may not be surprising, because the focus is primarily centered on only one half of the process – the teachers. The learners are the targets of the feedback process and improvement needs to be shifted. Learners need to be empowered with the skills needed to receive and utilize feedback and compensate for less than ideal feedback delivery due to the busy clinical environment. Methods Based on the available feedback literature and clinical experience regarding feedback, the author developed 10 tips to empower learners with the necessary skills to seek, receive, and handle feedback effectively, regardless of how it is delivered. Although, most of the tips are directed at the individual clinical trainee, this model can be utilized by clinical educators involved in learner development and serve as a framework for educational workshops or curriculum. Results Ten practical tips are identified that specifically address the learner's role in the feedback process. These tips not only help the learner to ask, receive, and handle the feedback, but will also ease the process for the teachers. Collectively, these tips help to overcome most, if not all, of the barriers to feedback and bridge the gaps in busy clinical practices. Conclusions Feedback is a crucial element in the educational process and it is shown that we are still behind in the optimal use of it; thus, learners need to be taught how to better receive and utilize feedback. The focus in medical education needs to balance the two sides of the feedback process. It is time now to invest on the learner's development of skills that can be utilized in a busy day-to-day clinical practice. PMID:25079664 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21463017','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21463017">Feedback and the rationing of time and effort among competing tasks.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Northcraft, Gregory B; Schmidt, Aaron M; Ashford, Susan J 2011-09-01 The study described here tested a model of how characteristics of the feedback environment influence the allocation of resources (time and effort) among competing tasks. Results demonstrated that performers invest more resources on tasks for which higher quality (more timely and more specific) feedback is available; this effect was partially mediated by task salience and task expectancies. Feedback timing and feedback specificity demonstrated both main and interaction effects on resource allocations. Results also demonstrated that performers do better on tasks for which higher quality feedback is available; this effect was mediated by resources allocated to tasks. The practical and theoretical implications of the role of the feedback environment in managing performance are discussed. PsycINFO Database Record (c) 2011 APA, all rights reserved </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=Biological&pg=7&id=EJ959261','ERIC'); return false;" href="https://eric.ed.gov/?q=Biological&pg=7&id=EJ959261">Student Engagement with Feedback</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Scott, Jon; Shields, Cathy; Gardner, James; Hancock, Alysoun; Nutt, Alex 2011-01-01 This report considers Biological Sciences students' perceptions of feedback, compared with those of the University as a whole, this includes what forms of feedback were considered most useful and how feedback used. Compared with data from previous studies, Biological Sciences students gave much greater recognition to oral feedback, placing it on a… </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1818313S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1818313S">On the Representation of Cloud Phase in Global Climate Models, and its Importance for Simulations of Climate Forcings and Feedbacks</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Storelvmo, Trude; Sagoo, Navjit; Tan, Ivy 2016-04-01 Despite the growing effort in improving the cloud microphysical schemes in GCMs, most of this effort has not focused on improving the ability of GCMs to accurately simulate phase partitioning in mixed-phase clouds. Getting the relative proportion of liquid droplets and ice crystals in clouds right in GCMs is critical for the representation of cloud radiative forcings and cloud-climate feedbacks. Here, we first present satellite observations of cloud phase obtained by NASA's CALIOP instrument, and report on robust statistical relationships between cloud phase and several aerosols species that have been demonstrated to act as ice nuclei (IN) in laboratory studies. We then report on results from model intercomparison projects that reveal that GCMs generally underestimate the amount of supercooled liquid in clouds. For a selected GCM (NCAR 's CAM5), we thereafter show that the underestimate can be attributed to two main factors: i) the presence of IN in the mixed-phase temperature range, and ii) the Wegener-Bergeron-Findeisen process, which converts liquid to ice once ice crystals have formed. Finally, we show that adjusting these two processes such that the GCM's cloud phase is in agreement with the observed has a substantial impact on the simulated radiative forcing due to IN perturbations, as well as on the cloud-climate feedbacks and ultimately climate sensitivity simulated by the GCM. </li> <li> <a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PhPro..25..749L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PhPro..25..749L">On the Feed-back Mechanism of Chinese Stock Markets</a> <a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a> Lu, Shu Quan; Ito, Takao; Zhang, Jianbo Feed-back models in the stock markets research imply an adjustment process toward investors' expectation for current information and past experiences. Error-correction and cointegration are often used to evaluate the long-run relation. The Efficient Capital Market Hypothesis, which had ignored the effect of the accumulation of information, cannot explain some anomalies such as bubbles and partial predictability in the stock markets. In order to investigate the feed-back mechanism and to determine an effective model, we use daily data of the stock index of two Chinese stock markets with the expectational model, which is one kind of geometric lag models. Tests and estimations of error-correction show that long-run equilibrium seems to be seldom achieved in Chinese stock markets. Our result clearly shows the common coefficient of expectations and fourth-order autoregressive disturbance exist in the two Chinese stock markets. Furthermore, we find the same coefficient of expectations has an autoregressive effect on disturbances in the two Chinese stock markets. Therefore the presence of such feed-back is also supported in Chinese stock markets. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3565692','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3565692">Acceleration feedback improves balancing against reflex delay</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Insperger, Tamás; Milton, John; Stépán, Gábor 2013-01-01 A model for human postural balance is considered in which the time-delayed feedback depends on position, velocity and acceleration (proportional–derivative–acceleration (PDA) feedback). It is shown that a PDA controller is equivalent to a predictive controller, in which the prediction is based on the most recent information of the state, but the control input is not involved into the prediction. A PDA controller is superior to the corresponding proportional–derivative controller in the sense that the PDA controller can stabilize systems with approximately 40 per cent larger feedback delays. The addition of a sensory dead zone to account for the finite thresholds for detection by sensory receptors results in highly intermittent, complex oscillations that are a typical feature of human postural sway. PMID:23173196 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28113520','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28113520">A Physics-Based Vibrotactile Feedback Library for Collision Events.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Park, Gunhyuk; Choi, Seungmoon 2017-01-01 We present PhysVib: a software solution on the mobile platform extending an open-source physics engine in a multi-rate rendering architecture for automatic vibrotactile feedback upon collision events. PhysVib runs concurrently with a physics engine at a low update rate and generates vibrotactile feedback commands at a high update rate based on the simulation results of the physics engine using an exponentially-decaying sinusoidal model. We demonstrate through a user study that this vibration model is more appropriate to our purpose in terms of perceptual quality than more complex models based on sound synthesis. We also evaluated the perceptual performance of PhysVib by comparing eight vibrotactile rendering methods. Experimental results suggested that PhysVib enables more realistic vibrotactile feedback than the other methods as to perceived similarity to the visual events. PhysVib is an effective solution for providing physically plausible vibrotactile responses while reducing application development time to great extent. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29347143','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29347143">Time-delayed feedback control of diffusion in random walkers.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Ando, Hiroyasu; Takehara, Kohta; Kobayashi, Miki U 2017-07-01 Time delay in general leads to instability in some systems, while specific feedback with delay can control fluctuated motion in nonlinear deterministic systems to a stable state. In this paper, we consider a stochastic process, i.e., a random walk, and observe its diffusion phenomenon with time-delayed feedback. As a result, the diffusion coefficient decreases with increasing delay time. We analytically illustrate this suppression of diffusion by using stochastic delay differential equations and justify the feasibility of this suppression by applying time-delayed feedback to a molecular dynamics model. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=open+AND+heart&id=EJ1140464','ERIC'); return false;" href="https://eric.ed.gov/?q=open+AND+heart&id=EJ1140464">Stop Sabotaging Feedback</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Stone, Douglas; David-Lang, Jenn 2017-01-01 School leaders need to be able to give and receive feedback--to give it skillfully to teachers, and to receive it skillfully from, well, everyone. Most educators agree that feedback can be necessary and helpful--yet the unending cascade of new directives governing feedback often feel like a waste of time. In this article, the authors offer… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=success+AND+criteria&pg=2&id=EJ1002436','ERIC'); return false;" href="https://eric.ed.gov/?q=success+AND+criteria&pg=2&id=EJ1002436">Preventing Feedback Fizzle</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Brookhart, Susan M. 2012-01-01 Feedback is certainly about saying or writing helpful, learning-focused comments. But that is only part of it. What happens beforehand? What happens afterward? Feedback that is helpful and learning-focused fits into a context. Before a teacher gives feedback, students need to know the learning target so they have a purpose for using the feedback… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5268650','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5268650">Alterations in Neural Control of Constant Isometric Contraction with the Size of Error Feedback</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Hwang, Ing-Shiou; Lin, Yen-Ting; Huang, Wei-Min; Yang, Zong-Ru; Hu, Chia-Ling; Chen, Yi-Ching 2017-01-01 Discharge patterns from a population of motor units (MUs) were estimated with multi-channel surface electromyogram and signal processing techniques to investigate parametric differences in low-frequency force fluctuations, MU discharges, and force-discharge relation during static force-tracking with varying sizes of execution error presented via visual feedback. Fourteen healthy adults produced isometric force at 10% of maximal voluntary contraction through index abduction under three visual conditions that scaled execution errors with different amplification factors. Error-augmentation feedback that used a high amplification factor (HAF) to potentiate visualized error size resulted in higher sample entropy, mean frequency, ratio of high-frequency components, and spectral dispersion of force fluctuations than those of error-reducing feedback using a low amplification factor (LAF). In the HAF condition, MUs with relatively high recruitment thresholds in the dorsal interosseous muscle exhibited a larger coefficient of variation for inter-spike intervals and a greater spectral peak of the pooled MU coherence at 13–35 Hz than did those in the LAF condition. Manipulation of the size of error feedback altered the force-discharge relation, which was characterized with non-linear approaches such as mutual information and cross sample entropy. The association of force fluctuations and global discharge trace decreased with increasing error amplification factor. Our findings provide direct neurophysiological evidence that favors motor training using error-augmentation feedback. Amplification of the visualized error size of visual feedback could enrich force gradation strategies during static force-tracking, pertaining to selective increases in the discharge variability of higher-threshold MUs that receive greater common oscillatory inputs in the β-band. PMID:28125658 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=swords&pg=6&id=EJ844102','ERIC'); return false;" href="https://eric.ed.gov/?q=swords&pg=6&id=EJ844102">The Nature of Feedback: How Different Types of Peer Feedback Affect Writing Performance</a> <a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a> Nelson, Melissa M.; Schunn, Christian D. 2009-01-01 Although providing feedback is commonly practiced in education, there is no general agreement regarding what type of feedback is most helpful and why it is helpful. This study examined the relationship between various types of feedback, potential internal mediators, and the likelihood of implementing feedback. Five main predictions were developed… </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4020807','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4020807">Feedforward-Feedback Hybrid Control for Magnetic Shape Memory Alloy Actuators Based on the Krasnosel'skii-Pokrovskii Model</a> <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a> Zhou, Miaolei; Zhang, Qi; Wang, Jingyuan 2014-01-01 As a new type of smart material, magnetic shape memory alloy has the advantages of a fast response frequency and outstanding strain capability in the field of microdrive and microposition actuators. The hysteresis nonlinearity in magnetic shape memory alloy actuators, however, limits system performance and further application. Here we propose a feedforward-feedback hybrid control method to improve control precision and mitigate the effects of the hysteresis nonlinearity of magnetic shape memory alloy actuators. First, hysteresis nonlinearity compensation for the magnetic shape memory alloy actuator is implemented by establishing a feedforward controller which is an inverse hysteresis model based on Krasnosel'skii-Pokrovskii operator. Secondly, the paper employs the classical Proportion Integration Differentiation feedback control with feedforward control to comprise the hybrid control system, and for further enhancing the adaptive performance of the system and improving the control accuracy, the Radial Basis Function neural network self-tuning Proportion Integration Differentiation feedback control replaces the classical Proportion Integration Differentiation feedback control. Utilizing self-learning ability of the Radial Basis Function neural network obtains Jacobian information of magnetic shape memory alloy actuator for the on-line adjustment of parameters in Proportion Integration Differentiation controller. Finally, simulation results show that the hybrid control method proposed in this paper can greatly improve the control precision of magnetic shape memory alloy actuator and the maximum tracking error is reduced from 1.1% in the open-loop system to 0.43% in the hybrid control system. PMID:24828010 </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24828010','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24828010">Feedforward-feedback hybrid control for magnetic shape memory alloy actuators based on the Krasnosel'skii-Pokrovskii model.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Zhou, Miaolei; Zhang, Qi; Wang, Jingyuan 2014-01-01 As a new type of smart material, magnetic shape memory alloy has the advantages of a fast response frequency and outstanding strain capability in the field of microdrive and microposition actuators. The hysteresis nonlinearity in magnetic shape memory alloy actuators, however, limits system performance and further application. Here we propose a feedforward-feedback hybrid control method to improve control precision and mitigate the effects of the hysteresis nonlinearity of magnetic shape memory alloy actuators. First, hysteresis nonlinearity compensation for the magnetic shape memory alloy actuator is implemented by establishing a feedforward controller which is an inverse hysteresis model based on Krasnosel'skii-Pokrovskii operator. Secondly, the paper employs the classical Proportion Integration Differentiation feedback control with feedforward control to comprise the hybrid control system, and for further enhancing the adaptive performance of the system and improving the control accuracy, the Radial Basis Function neural network self-tuning Proportion Integration Differentiation feedback control replaces the classical Proportion Integration Differentiation feedback control. Utilizing self-learning ability of the Radial Basis Function neural network obtains Jacobian information of magnetic shape memory alloy actuator for the on-line adjustment of parameters in Proportion Integration Differentiation controller. Finally, simulation results show that the hybrid control method proposed in this paper can greatly improve the control precision of magnetic shape memory alloy actuator and the maximum tracking error is reduced from 1.1% in the open-loop system to 0.43% in the hybrid control system. </li> <li> <a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21350383','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21350383">Relationships among supervisor feedback environment, work-related stressors, and employee deviance.</a> <a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a> Peng, Jei-Chen; Tseng, Mei-Man; Lee, Yin-Ling 2011-03-01 Previous research has demonstrated that the employee deviance imposes enormous costs on organizational performance and productivity. Similar research supports the positive effect of favorable supervisor feedback on employee job performance. In light of such, it is important to understand the interaction between supervisor feedback environment and employee deviant behavior to streamline organization operations. The purposes of this study were to explore how the supervisor feedback environment influences employee deviance and to examine the mediating role played by work-related stressors. Data were collected from 276 subordinate-supervisor dyads at a regional hospital in Yilan. Structural equation modeling analyses were conducted to test hypotheses. Structural equation modeling analysis results show that supervisor feedback environment negatively related to interpersonal and organizational deviance. Moreover, work-related stressors were found to partially mediate the relationship between supervisor feedback environment and employee deviance. Study findings suggest that when employees (nurses in this case) perceive an appropriate supervisor-provided feedback environment, their deviance is suppressed because of the related reduction in work-related stressors. Thus, to decrease deviant behavior, organizations may foster supervisor integration of disseminated knowledge such as (a) how to improve employees' actual performance, (b) how to effectively clarify expected performance, and (c) how to improve continuous performance feedback. If supervisors absorb this integrated feedback knowledge, they should be in a better position to enhance their own daily interactions with nurses and reduce nurses' work-related stress and, consequently, decrease deviant behavior. </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active">25</li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> </div> <div class="footer-extlink text-muted" style="margin-bottom:1rem; text-align:center;">Some links on this page may take you to non-federal websites. Their policies may differ from this site.</div> </div> <footer><a id="backToTop" href="#top"> </a><nav><a id="backToTop" href="#top"> </a><ul class="links"><a id="backToTop" href="#top"> </a><li><a id="backToTop" href="#top"></a><a href="/sitemap.html">Site Map</a></li> <li><a href="/members/index.html">Members Only</a></li> <li><a href="/website-policies.html">Website Policies</a></li> <li><a href="https://doe.responsibledisclosure.com/hc/en-us" target="_blank">Vulnerability Disclosure Program</a></li> <li><a href="/contact.html">Contact Us</a></li> </ul> <div class="small">Science.gov is maintained by the U.S. Department of Energy's <a href="https://www.osti.gov/" target="_blank">Office of Scientific and Technical Information</a>, in partnership with <a href="https://www.cendi.gov/" target="_blank">CENDI</a>.</div> </nav> </footer> <script type="text/javascript"> </script> <script> /** * Function that tracks a click on an outbound link in Google Analytics. * This function takes a valid URL string as an argument, and uses that URL string * as the event label. */ var trackOutboundLink = function(url,collectionCode) { try { h = window.open(url); setTimeout(function() { ga('send', 'event', 'topic-page-click-through', collectionCode, url); }, 1000); } catch(err){} }; </script>  <script> (function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){ (i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o), m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m) })(window,document,'script','//www.google-analytics.com/analytics.js','ga'); ga('create', 'UA-1122789-34', 'auto'); ga('send', 'pageview'); </script>  <script> showDiv('page_1') </script> </body> </html>

Sample records for factor feedback model