Analyzing the Effect of Spinning Process Variables on Draw Frame Blended Cotton Mélange Yarn Quality

NASA Astrophysics Data System (ADS)

Ray, Suchibrata; Ghosh, Anindya; Banerjee, Debamalya

2018-06-01

An investigation has been made to study the effect of important spinning process variables namely shade depth, ring frame spindle speed and yarn twist multiplier (TM) on various yarn quality parameters like unevenness, strength, imperfection, elongation at break and hairiness index of draw frame blended cotton mélange yarn. Three factors Box and Behnken design of experiment has been used to conduct the study. The quadratic regression model is used to device the statistical inferences about sensitivity of the yarn quality parameters to the different process variables. The response surfaces are constructed for depicting the geometric representation of yarn quality parameters plotted as a function of process variables. Analysis of the results show that yarn strength of draw frame blended cotton mélange yarn is significantly affected by shade depth and TM. Yarn unevenness is affected by shade depth and ring frame spindle speed. Yarn imperfection level is mainly influenced by the shade depth and spindle speed. The shade depth and yarn TM have shown significant impact on yarn hairiness index.

Analyzing the Effect of Spinning Process Variables on Draw Frame Blended Cotton Mélange Yarn Quality

NASA Astrophysics Data System (ADS)

Ray, Suchibrata; Ghosh, Anindya; Banerjee, Debamalya

2017-12-01

An investigation has been made to study the effect of important spinning process variables namely shade depth, ring frame spindle speed and yarn twist multiplier (TM) on various yarn quality parameters like unevenness, strength, imperfection, elongation at break and hairiness index of draw frame blended cotton mélange yarn. Three factors Box and Behnken design of experiment has been used to conduct the study. The quadratic regression model is used to device the statistical inferences about sensitivity of the yarn quality parameters to the different process variables. The response surfaces are constructed for depicting the geometric representation of yarn quality parameters plotted as a function of process variables. Analysis of the results show that yarn strength of draw frame blended cotton mélange yarn is significantly affected by shade depth and TM. Yarn unevenness is affected by shade depth and ring frame spindle speed. Yarn imperfection level is mainly influenced by the shade depth and spindle speed. The shade depth and yarn TM have shown significant impact on yarn hairiness index.

The association of external knee adduction moment with biomechanical variables in osteoarthritis: a systematic review.

PubMed

Foroughi, Nasim; Smith, Richard; Vanwanseele, Benedicte

2009-10-01

Osteoarthritis (OA) is a musculoskeletal disorder primarily affecting the older population and resulting in chronic pain and disability. Biomechanical variables, associated with OA severity such as external knee adduction moment (KAM) and joint malalignment, may affect the disease process by altering the bone-on-bone forces during gait. To investigate the association between biomechanical variables and KAM in knee OA. A systematic search for published studies' titles and abstracts was performed on Ovid Medline, Cumulative index to Nursing and Allied Health, PREMEDLINE, EBM reviews and SPORTDiscus. Fourteen studies met the inclusion criteria and were considered for the review. The magnitude and time course of KAM during gait appeared to be consistent across laboratories and computational methods. Only two of the included studies that compared patients with OA to a control group reported a higher peak KAM for the OA group. Knee adduction moment increased with OA severity and was directly proportional to varus malalignment. Classifying the patients on the basis of disease severity decreased the group variability, permitting the differences to be more detectable. Biomechanical variables such as varus malalignment are associated with KAM and therefore may affect the disease process. These variables should be taken into considerations when developing therapeutic interventions for individuals suffering from knee OA.

A Framework for Categorizing Important Project Variables

NASA Technical Reports Server (NTRS)

Parsons, Vickie S.

2003-01-01

While substantial research has led to theories concerning the variables that affect project success, no universal set of such variables has been acknowledged as the standard. The identification of a specific set of controllable variables is needed to minimize project failure. Much has been hypothesized about the need to match project controls and management processes to individual projects in order to increase the chance for success. However, an accepted taxonomy for facilitating this matching process does not exist. This paper surveyed existing literature on classification of project variables. After an analysis of those proposals, a simplified categorization is offered to encourage further research.

Training and Older Workers: Implications for U.S. Competitiveness. Contract Report.

ERIC Educational Resources Information Center

Rothstein, Frances R.; Ratte, Donna J.

Age-related changes in functional ability and work attitude affect job performance, but many variables affect the extent and timing of change for different older workers. Declines due to age occur in sensory/perceptual processes; strength, speed and accuracy of movement, and balance; and cognitive processes. Individuals can compensate for some…

Intrinsic colony conditions affect the provisioning and oviposition process in the stingless bee Melipona scutellaris.

PubMed

Pereira, R A; Morais, M M; Nascimento, F S; Bego, L R

2009-01-01

The cell provisioning and oviposition process (POP) is a unique characteristic of stingless bees (Meliponini), in which coordinated interactions between workers and queen regulate the filling of brood cells with larval resources and subsequent egg laying. Environmental conditions seem to regulate reproduction in stingless bees; however, little is known about how the amount of food affects quantitative sequences of the process. We examined intrinsic variables by comparing three colonies in distinct conditions (strong, intermediate and weak state). We predicted that some of these variables are correlated with temporal events of POP in Melipona scutellaris colonies. The results demonstrated that the strong colony had shorter periods of POP.

Latent structure analysis of the process variables and pharmaceutical responses of an orally disintegrating tablet.

PubMed

Hayashi, Yoshihiro; Oshima, Etsuko; Maeda, Jin; Onuki, Yoshinori; Obata, Yasuko; Takayama, Kozo

2012-01-01

A multivariate statistical technique was applied to the design of an orally disintegrating tablet and to clarify the causal correlation among variables of the manufacturing process and pharmaceutical responses. Orally disintegrating tablets (ODTs) composed mainly of mannitol were prepared via the wet-granulation method using crystal transition from the δ to the β form of mannitol. Process parameters (water amounts (X(1)), kneading time (X(2)), compression force (X(3)), and amounts of magnesium stearate (X(4))) were optimized using a nonlinear response surface method (RSM) incorporating a thin plate spline interpolation (RSM-S). The results of a verification study revealed that the experimental responses, such as tensile strength and disintegration time, coincided well with the predictions. A latent structure analysis of the pharmaceutical formulations of the tablet performed using a Bayesian network led to the clear visualization of a causal connection among variables of the manufacturing process and tablet characteristics. The quantity of β-mannitol in the granules (Q(β)) was affected by X(2) and influenced all granule properties. The specific surface area of the granules was affected by X(1) and Q(β) and had an effect on all tablet characteristics. Moreover, the causal relationships among the variables were clarified by inferring conditional probability distributions. These techniques provide a better understanding of the complicated latent structure among variables of the manufacturing process and tablet characteristics.

Sometimes processes don't matter: the general effect of short term climate variability on erosional systems.

NASA Astrophysics Data System (ADS)

Deal, Eric; Braun, Jean

2017-04-01

Climatic forcing undoubtedly plays an important role in shaping the Earth's surface. However, precisely how climate affects erosion rates, landscape morphology and the sedimentary record is highly debated. Recently there has been a focus on the influence of short-term variability in rainfall and river discharge on the relationship between climate and erosion rates. Here, we present a simple probabilistic argument, backed by modelling, that demonstrates that the way the Earth's surface responds to short-term climatic forcing variability is primarily determined by the existence and magnitude of erosional thresholds. We find that it is the ratio between the threshold magnitude and the mean magnitude of climatic forcing that determines whether variability matters or not and in which way. This is a fundamental result that applies regardless of the nature of the erosional process. This means, for example, that we can understand the role that discharge variability plays in determining fluvial erosion efficiency despite doubts about the processes involved in fluvial erosion. We can use this finding to reproduce the main conclusions of previous studies on the role of discharge variability in determining long-term fluvial erosion efficiency. Many aspects of the landscape known to influence discharge variability are affected by human activity, such as land use and river damming. Another important control on discharge variability, rainfall intensity, is also expected to increase with warmer temperatures. Among many other implications, our findings help provide a general framework to understand and predict the response of the Earth's surface to changes in mean and variability of rainfall and river discharge associated with the anthropogenic activity. In addition, the process independent nature of our findings suggest that previous work on river discharge variability and erosion thresholds can be applied to other erosional systems.

The impact of inter-annual rainfall variability on food production in the Ganges basin

NASA Astrophysics Data System (ADS)

Siderius, Christian; Biemans, Hester; van Walsum, Paul; hellegers, Petra; van Ierland, Ekko; Kabat, Pavel

2014-05-01

Rainfall variability is expected to increase in the coming decades as the world warms. Especially in regions already water stressed, a higher rainfall variability will jeopardize food security. Recently, the impact of inter-annual rainfall variability has received increasing attention in regional to global analysis on water availability and food security. But the description of the dynamics behind it is still incomplete in most models. Contemporary land surface and hydrological models used for such analyses describe variability in production primarily as a function of yield, a process driven by biophysical parameters, thereby neglecting yearly variations in cropped area, a process driven largely by management decisions. Agricultural statistics for northern India show that the latter process could explain up to 40% of the observed inter-annual variation in food production in various states. We added a simple dynamic land use decision module to a land surface model (LPJmL) and analyzed to what extent this improved the estimation of variability in food production. Using this improved modelling framework we then assessed if and at which scale rainfall variability affects meeting the food self-sufficiency threshold. Early results for the Ganges Basin indicate that, while on basin level variability in crop production is still relatively low, several districts and states are highly affected (RSTD > 50%). Such insight can contribute to better recommendations on the most effective measures, at the most appropriate scale, to buffer variability in food production.

Troubleshooting crude vacuum tower overhead ejector systems

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

Lines, J.R.; Frens, L.L.

1995-03-01

Routinely surveying tower overhead vacuum systems can improve performance and product quality. These vacuum systems normally provide reliable and consistent operation. However, process conditions, supplied utilities, corrosion, erosion and fouling all have an impact on ejector system performance. Refinery vacuum distillation towers use ejector systems to maintain tower top pressure and remove overhead gases. However, as with virtually all refinery equipment, performance may be affected by a number of variables. These variables may act independently or concurrently. It is important to understand basic operating principles of vacuum systems and how performance is affected by: utilities, corrosion and erosion, fouling, andmore » process conditions. Reputable vacuum-system suppliers have service engineers that will come to a refinery to survey the system and troubleshoot performance or offer suggestions for improvement. A skilled vacuum-system engineer may be needed to diagnose and remedy system problems. The affect of these variables on performance is discussed. A case history is described of a vacuum system on a crude tower in a South American refinery.« less

Processes Affecting the Annual Surface Energy Budget at High-Latitude Terrestrial Sites

NASA Astrophysics Data System (ADS)

Persson, P. O. G.; Stone, R. S.; Grachev, A.; Matrosova, L.

2012-04-01

Instrumentation at four Study of Environmental Arctic Change (SEARCH) sites (Barrow, Eureka, Alert, and Tiksi) have been enhanced in the past 6 years, including during the 2007-2008 IPY. Data from these sites are used to investigate the annual cycle of the surface energy budget (SEB), its coupling to atmospheric processes, and for Alert, its interannual variability. The comprehensive data sets are useful for showing interactions between the atmosphere, surface, and soil at high temporal resolution throughout the annual cycle. Processes that govern the SEB variability at each site are identified, and their impacts on the SEB are quantified. For example, mesoscale modulation of the SEB caused by forcing from the local terrain (downslope wind events) and coastlines (sea and land breezes) are significant at Alert and Eureka, with these processes affecting both radiative, turbulent, and ground heat flux terms in the SEB. Sub-seasonal and interannual variations in atmospheric processes and SEB impact soil thermal structures, such as the depth and timing of the summer active layer. These analyses provide an improved understanding of the processes producing changes in surface and soil temperature, linking them through the SEB as affected by atmospheric processes.

Factors affecting medication-order processing time.

PubMed

Beaman, M A; Kotzan, J A

1982-11-01

The factors affecting medication-order processing time at one hospital were studied. The order processing time was determined by directly observing the time to process randomly selected new drug orders on all three work shifts during two one-week periods. An order could list more than one drug for an individual patient. The observer recorded the nature, location, and cost of the drugs ordered, as well as the time to process the order. The time and type of interruptions also were noted. The time to process a drug order was classified as six dependent variables: (1) total time, (2) work time, (3) check time, (4) waiting time I--time from arrival on the dumbwaiter until work was initiated, (5) waiting time II--time between completion of the work and initiation of checking, and (6) waiting time III--time after the check was completed until the order left on the dumbwaiter. The significant predictors of each of the six dependent variables were determined using stepwise multiple regression. The total time to process a prescription order was 58.33 +/- 48.72 minutes; the urgency status of the order was the only significant determinant of total time. Urgency status also significantly predicted the three waiting-time variables. Interruptions and the number of drugs on the order were significant determinants of work time and check time. Each telephone interruption increased the work time by 1.72 minutes. While the results of this study cannot be generalized to other institutions, pharmacy managers can use the method of determining factors that affect medication-order processing time to identify problem areas in their institutions.

Variables in Human Consequation/Feedback.

DTIC Science & Technology

1979-07-31

that make consequators effective , in each case listed according to the aspects that characterize them and their relationships with consequators ; another...category consists of the purposes and effects of consequated actions. The compilation draws variables from both cognitive research in information...This report presents salient variables in consequation or feedback processes that affect human behavior. As comprehensive a compilation has not been

The role of personal self-regulation and regulatory teaching to predict motivational-affective variables, achievement, and satisfaction: a structural model

PubMed Central

De la Fuente, Jesus; Zapata, Lucía; Martínez-Vicente, Jose M.; Sander, Paul; Cardelle-Elawar, María

2014-01-01

The present investigation examines how personal self-regulation (presage variable) and regulatory teaching (process variable of teaching) relate to learning approaches, strategies for coping with stress, and self-regulated learning (process variables of learning) and, finally, how they relate to performance and satisfaction with the learning process (product variables). The objective was to clarify the associative and predictive relations between these variables, as contextualized in two different models that use the presage-process-product paradigm (the Biggs and DEDEPRO models). A total of 1101 university students participated in the study. The design was cross-sectional and retrospective with attributional (or selection) variables, using correlations and structural analysis. The results provide consistent and significant empirical evidence for the relationships hypothesized, incorporating variables that are part of and influence the teaching–learning process in Higher Education. Findings confirm the importance of interactive relationships within the teaching–learning process, where personal self-regulation is assumed to take place in connection with regulatory teaching. Variables that are involved in the relationships validated here reinforce the idea that both personal factors and teaching and learning factors should be taken into consideration when dealing with a formal teaching–learning context at university. PMID:25964764

Examining the causes of memory strength variability: Recollection, attention failure, or encoding variability?

PubMed Central

Koen, Joshua D.; Aly, Mariam; Wang, Wei-Chun; Yonelinas, Andrew P.

2013-01-01

A prominent finding in recognition memory is that studied items are associated with more variability in memory strength than new items. Here, we test three competing theories for why this occurs - the encoding variability, attention failure, and recollection accounts. Distinguishing amongst these theories is critical because each provides a fundamentally different account of the processes underlying recognition memory. The encoding variability and attention failure accounts propose that old item variance will be unaffected by retrieval manipulations because the processes producing this effect are ascribed to encoding. The recollection account predicts that both encoding and retrieval manipulations that preferentially affect recollection will affect memory variability. These contrasting predictions were tested by examining the effect of response speeding (Experiment 1), dividing attention at retrieval (Experiment 2), context reinstatement (Experiment 3), and increased test delay (Experiment 4) on recognition performance. The results of all four experiments confirmed the predictions of the recollection account, and were inconsistent with the encoding variability account. The evidence supporting the attention failure account was mixed, with two of the four experiments confirming the account and two disconfirming the account. These results indicate that encoding variability and attention failure are insufficient accounts of memory variance, and provide support for the recollection account. Several alternative theoretical accounts of the results are also considered. PMID:23834057

A gentle introduction to quantile regression for ecologists

USGS Publications Warehouse

Cade, B.S.; Noon, B.R.

2003-01-01

Quantile regression is a way to estimate the conditional quantiles of a response variable distribution in the linear model that provides a more complete view of possible causal relationships between variables in ecological processes. Typically, all the factors that affect ecological processes are not measured and included in the statistical models used to investigate relationships between variables associated with those processes. As a consequence, there may be a weak or no predictive relationship between the mean of the response variable (y) distribution and the measured predictive factors (X). Yet there may be stronger, useful predictive relationships with other parts of the response variable distribution. This primer relates quantile regression estimates to prediction intervals in parametric error distribution regression models (eg least squares), and discusses the ordering characteristics, interval nature, sampling variation, weighting, and interpretation of the estimates for homogeneous and heterogeneous regression models.

Spatial Variability of Dissolved Organic Carbon in Headwater Wetlands in Central Pennsylvania

NASA Astrophysics Data System (ADS)

Reichert-Eberhardt, A. J.; Wardrop, D.; Boyer, E. W.

2011-12-01

Dissolved organic carbon (DOC) is known to be of an important factor in many microbially mediated biochemical processes, such as denitrification, that occur in wetlands. The spatial variability of DOC within a wetland could impact the microbes that fuel these processes, which in turn can affect the ecosystem services provided by wetlands. However, the amount of spatial variability of DOC in wetlands is generally unknown. Furthermore, it is unknown how disturbance to wetlands can affect spatial variability of DOC. Previous research in central Pennsylvania headwater wetland soils has shown that wetlands with increased human disturbance had decreased heterogeneity in soil biochemistry. To address groundwater chemical variability 20 monitoring wells were installed in a random pattern in a 400 meter squared plot in a low-disturbance headwater wetland and a high-disturbance headwater wetland in central Pennsylvania. Water samples from these wells will be analyzed for DOC, dissolved inorganic carbon, nitrate, ammonia, and sulfate concentrations, as well as pH, conductivity, and temperature on a seasonal basis. It is hypothesized that there will be greater spatial variability of groundwater chemistry in the low disturbance wetland than the high disturbance wetland. This poster will present the initial data concerning DOC spatial variability in both the low and high impact headwater wetlands.

Guidelines for the Investigation of Mediating Variables in Business Research.

PubMed

MacKinnon, David P; Coxe, Stefany; Baraldi, Amanda N

2012-03-01

Business theories often specify the mediating mechanisms by which a predictor variable affects an outcome variable. In the last 30 years, investigations of mediating processes have become more widespread with corresponding developments in statistical methods to conduct these tests. The purpose of this article is to provide guidelines for mediation studies by focusing on decisions made prior to the research study that affect the clarity of conclusions from a mediation study, the statistical models for mediation analysis, and methods to improve interpretation of mediation results after the research study. Throughout this article, the importance of a program of experimental and observational research for investigating mediating mechanisms is emphasized.

On the upscaling of process-based models in deltaic applications

NASA Astrophysics Data System (ADS)

Li, L.; Storms, J. E. A.; Walstra, D. J. R.

2018-03-01

Process-based numerical models are increasingly used to study the evolution of marine and terrestrial depositional environments. Whilst a detailed description of small-scale processes provides an accurate representation of reality, application on geological timescales is restrained by the associated increase in computational time. In order to reduce the computational time, a number of acceleration methods are combined and evaluated for a schematic supply-driven delta (static base level) and an accommodation-driven delta (variable base level). The performance of the combined acceleration methods is evaluated by comparing the morphological indicators such as distributary channel networking and delta volumes derived from the model predictions for various levels of acceleration. The results of the accelerated models are compared to the outcomes from a series of simulations to capture autogenic variability. Autogenic variability is quantified by re-running identical models on an initial bathymetry with 1 cm added noise. The overall results show that the variability of the accelerated models fall within the autogenic variability range, suggesting that the application of acceleration methods does not significantly affect the simulated delta evolution. The Time-scale compression method (the acceleration method introduced in this paper) results in an increased computational efficiency of 75% without adversely affecting the simulated delta evolution compared to a base case. The combination of the Time-scale compression method with the existing acceleration methods has the potential to extend the application range of process-based models towards geologic timescales.

The Effect of Propellant Variables on Slag in Subscale Spin Motors. Part 1; Design and Qualification of a Slag Discrimination Motor

NASA Technical Reports Server (NTRS)

Perkins, F. M.; Beus, R. W.; May, D. H.

1995-01-01

The formation, collection, and expulsion of aluminum oxide slag is known to affect the performance of many solid rocket motor systems. Slag expulsion, in particular, is believed to be capable of causing pressure and thrust perturbations. Propellant combustion studies, performed and documented by many investigators, have shown that variations in propellant raw materials and processing affect the nature of alumina droplets at the burning propellant surface, and hence, may affect the quantity of slag retained in the motor chamber, available for expulsion. Thiokol has completed an experimental and analytical evaluation to determine the effects of several material and process variables on Space SHuttle propellant and its propensity to 'slag'. This paper describes the test article, a small scale spin motor with special nozzle, designed and qualified as a slag discriminating tool for use in the evaluation.

Affective Computing and the Impact of Gender and Age

PubMed Central

Rukavina, Stefanie; Gruss, Sascha; Hoffmann, Holger; Tan, Jun-Wen; Walter, Steffen; Traue, Harald C.

2016-01-01

Affective computing aims at the detection of users’ mental states, in particular, emotions and dispositions during human-computer interactions. Detection can be achieved by measuring multimodal signals, namely, speech, facial expressions and/or psychobiology. Over the past years, one major approach was to identify the best features for each signal using different classification methods. Although this is of high priority, other subject-specific variables should not be neglected. In our study, we analyzed the effect of gender, age, personality and gender roles on the extracted psychobiological features (derived from skin conductance level, facial electromyography and heart rate variability) as well as the influence on the classification results. In an experimental human-computer interaction, five different affective states with picture material from the International Affective Picture System and ULM pictures were induced. A total of 127 subjects participated in the study. Among all potentially influencing variables (gender has been reported to be influential), age was the only variable that correlated significantly with psychobiological responses. In summary, the conducted classification processes resulted in 20% classification accuracy differences according to age and gender, especially when comparing the neutral condition with four other affective states. We suggest taking age and gender specifically into account for future studies in affective computing, as these may lead to an improvement of emotion recognition accuracy. PMID:26939129

Examining the causes of memory strength variability: recollection, attention failure, or encoding variability?

PubMed

Koen, Joshua D; Aly, Mariam; Wang, Wei-Chun; Yonelinas, Andrew P

2013-11-01

A prominent finding in recognition memory is that studied items are associated with more variability in memory strength than new items. Here, we test 3 competing theories for why this occurs-the encoding variability, attention failure, and recollection accounts. Distinguishing among these theories is critical because each provides a fundamentally different account of the processes underlying recognition memory. The encoding variability and attention failure accounts propose that old item variance will be unaffected by retrieval manipulations because the processes producing this effect are ascribed to encoding. The recollection account predicts that both encoding and retrieval manipulations that preferentially affect recollection will affect memory variability. These contrasting predictions were tested by examining the effect of response speeding (Experiment 1), dividing attention at retrieval (Experiment 2), context reinstatement (Experiment 3), and increased test delay (Experiment 4) on recognition performance. The results of all 4 experiments confirm the predictions of the recollection account and are inconsistent with the encoding variability account. The evidence supporting the attention failure account is mixed, with 2 of the 4 experiments confirming the account and 2 disconfirming the account. These results indicate that encoding variability and attention failure are insufficient accounts of memory variance and provide support for the recollection account. Several alternative theoretical accounts of the results are also considered. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Stability of Intercellular Exchange of Biochemical Substances Affected by Variability of Environmental Parameters

NASA Astrophysics Data System (ADS)

Mihailović, Dragutin T.; Budinčević, Mirko; Balaž, Igor; Mihailović, Anja

Communication between cells is realized by exchange of biochemical substances. Due to internal organization of living systems and variability of external parameters, the exchange is heavily influenced by perturbations of various parameters at almost all stages of the process. Since communication is one of essential processes for functioning of living systems it is of interest to investigate conditions for its stability. Using previously developed simplified model of bacterial communication in a form of coupled difference logistic equations we investigate stability of exchange of signaling molecules under variability of internal and external parameters.

Mental training enhances attentional stability: Neural and behavioral evidence

PubMed Central

Lutz, Antoine; Slagter, Heleen A.; Rawlings, Nancy B.; Francis, Andrew D.; Greischar, Lawrence L.; Davidson, Richard J.

2009-01-01

The capacity to stabilize the content of attention over time varies among individuals and its impairment is a hallmark of several mental illnesses. Impairments in sustained attention in patients with attention disorders have been associated with increased trial-to-trial variability in reaction time and event-related potential (ERP) deficits during attention tasks. At present, it is unclear whether the ability to sustain attention and its underlying brain circuitry are transformable through training. Here, we show, with dichotic listening task performance and electroencephalography (EEG), that training attention, as cultivated by meditation, can improve the ability to sustain attention. Three months of intensive meditation training reduced variability in attentional processing of target tones, as indicated by both enhanced theta-band phase consistency of oscillatory neural responses over anterior brain areas and reduced reaction time variability. Furthermore, those individuals who showed the greatest increase in neural response consistency showed the largest decrease in behavioral response variability. Notably, we also observed reduced variability in neural processing, in particular in low-frequency bands, regardless of whether the deviant tone was attended or unattended. Focused attention meditation may thus affect both distracter and target processing, perhaps by enhancing entrainment of neuronal oscillations to sensory input rhythms; a mechanism important for controlling the content of attention. These novel findings highlight the mechanisms underlying focused attention meditation, and support the notion that mental training can significantly affect attention and brain function. PMID:19846729

Graduate Students as Academic Writers: Writing Anxiety, Self-Efficacy and Emotional Intelligence

ERIC Educational Resources Information Center

Huerta, Margarita; Goodson, Patricia; Beigi, Mina; Chlup, Dominique

2017-01-01

Researchers interested in psychological factors affecting writers in higher-education institutions, or academic writers, are concerned with internal variables affecting writing productivity; however few empirical studies explore these factors with samples of students who are in the process of earning master's or doctoral degrees (i.e., graduate…

Factors Affecting Students' Self-Efficacy in Higher Education

ERIC Educational Resources Information Center

van Dinther, Mart; Dochy, Filip; Segers, Mien

2011-01-01

Researchers working in educational settings are increasingly paying attention to the role students' thoughts and beliefs play in the learning process. Self-efficacy, a key element of social cognitive theory, appears to be an important variable because it affects students' motivation and learning. This article investigates empirical literature…

Cognitive Style Predictors of Affect Change in Older Adults

ERIC Educational Resources Information Center

Isaacowitz, Derek M.; Seligman, Martin E. P.

2002-01-01

Cognitive styles are the lenses through which individuals habitually process information from their environment. In this study, we evaluated whether different cognitive style individual difference variables, such as explanatory style and dispositional optimism, could predict changes in affective state over time in community-dwelling older adults.…

Predicting Vaccination Intention and Benefit and Risk Perceptions: The Incorporation of Affect, Trust, and Television Influence in a Dual-Mode Model.

PubMed

Chen, Nien-Tsu Nancy

2015-07-01

Major health behavior change models tend to consider health decisions as primarily resulting from a systematic appraisal of relevant beliefs, such as the perceived benefits and risks of a pharmacological intervention. Drawing on research from the disciplines of risk management, communication, and psychology, this study proposed the inclusion of a heuristic route in established theory and tested the direction of influence between heuristic and systematic process variables. Affect and social trust were included as key heuristics in the proposed dual-mode framework of health decision making. Furthermore, exposure to health-related coverage on television was considered potentially influential over both heuristic and systematic process variables. To test this framework, data were collected from a national probability sample of 584 adults in the United States in 2012 regarding their decision to vaccinate against a hypothetical avian flu. The results provided some support for the bidirectional influence between heuristic and systematic processing. Affect toward flu vaccination and trust in the Food and Drug Administration were found to be powerful predictors of vaccination intention, enhancing intention both directly and indirectly via certain systematic process variables. The direction of influence between perceived susceptibility and severity, on the one hand, and affect, on the other, is less clear, suggesting the need for further research. Contrary to the opinion of media critics, exposure to televised health coverage was negatively associated with the perceived risks of vaccination. Results from this study carry theoretical and practical implications, and applying this model to the acceptance of different health interventions constitutes an area for future inquiries. © 2015 Society for Risk Analysis.

A comparison of four typical green exercise environments and prediction of psychological health outcomes.

PubMed

Rogerson, Mike; Brown, Daniel K; Sandercock, Gavin; Wooller, John-James; Barton, Jo

2016-05-01

'Green exercise' (GE) is physical activity while simultaneously being exposed to nature. GE comprises three physical components: the individual, the exercise and the environment, and one processes component encompassing a range of psychological and physiological processes. Previous research has consistently shown affective benefits of GE compared to equivalent non-GE. Investigating the possibility of optimum GE environments may help maximise health benefits. The aim of this study was to compare affective outcomes of GE participation between four different typical GE environments (beach, grasslands, riverside, heritage), and further examine influences of several physical component-related variables and one processes component-related variable, on these outcomes. Participants (N = 331) completed questionnaires before and after a 5km run, at one of four parkrun event locations. Self-esteem (Δ = 1.61, 95% confidence interval (CI) = (1.30, 1.93)), stress (Δ = -2.36, 95% CI = (-3.01, -1.71)) and mood (Δ = -5.25, 95% CI = (-7.45, -3.05)) all significantly improved from pre- to post-run (p < .05). Improvements in these measures were not significantly different between environments. Several component-related variables significantly predicted these improvements, accounting for 9% of self-esteem improvement, 1.6% of perceived stress improvement, and 9.5% of mood improvement. GE offers accessible provision for improving acute psychological wellbeing. Although nature-based exercise environments can facilitate affective outcomes, the overall type of nature may be less critical. Other characteristics of the individual, exercise and environment can significantly influence attainment of psychological GE benefits. However, the results support a greater importance of the processes component in attaining previously reported affective outcomes. © Royal Society for Public Health 2015.

Factors Affecting Relationships between the Contextual Variables and the Information Characteristics of Accounting Information Systems.

ERIC Educational Resources Information Center

Choe, Jong-Min; Lee, Jinjoo

1993-01-01

Reports on a study of accounting information systems that explored the interactions among influence factors (e.g., user participation in the development process, top management support, capability of information systems personnel, and existence of steering committees), contextual variables (e.g., organizational structure and task characteristics),…

Perceptual Learning Style Preferences among Iranian Graduate Students

ERIC Educational Resources Information Center

Naserieh, Farid; Sarab, Mohammad Reza Anani

2013-01-01

Research suggests that a host of cognitive, affective, and perceptual variables are at work when individuals go about the task of second or foreign language learning. Among these variables are learning styles that are habitual ways of perceiving, processing, and storing information. This study was conducted as a response to Isemonger and…

Designed experiment evaluation of key variables affecting the cutting performance of rotary instruments.

PubMed

Funkenbusch, Paul D; Rotella, Mario; Ercoli, Carlo

2015-04-01

Laboratory studies of tooth preparation are often performed under a limited range of conditions involving single values for all variables other than the 1 being tested. In contrast, in clinical settings not all variables can be tightly controlled. For example, a new dental rotary cutting instrument may be tested in the laboratory by making a specific cut with a fixed force, but in clinical practice, the instrument must make different cuts with individual dentists applying a range of different forces. Therefore, the broad applicability of laboratory results to diverse clinical conditions is uncertain and the comparison of effects across studies is difficult. The purpose of this study was to examine the effect of 9 process variables on dental cutting in a single experiment, allowing each variable to be robustly tested over a range of values for the other 8 and permitting a direct comparison of the relative importance of each on the cutting process. The effects of 9 key process variables on the efficiency of a simulated dental cutting operation were measured. A fractional factorial experiment was conducted by using a computer-controlled, dedicated testing apparatus to simulate dental cutting procedures and Macor blocks as the cutting substrate. Analysis of Variance (ANOVA) was used to judge the statistical significance (α=.05). Five variables consistently produced large, statistically significant effects (target applied load, cut length, starting rpm, diamond grit size, and cut type), while 4 variables produced relatively small, statistically insignificant effects (number of cooling ports, rotary cutting instrument diameter, disposability, and water flow rate). The control exerted by the dentist, simulated in this study by targeting a specific level of applied force, was the single most important factor affecting cutting efficiency. Cutting efficiency was also significantly affected by factors simulating patient/clinical circumstances as well as hardware choices. These results highlight the importance of local clinical conditions (procedure, dentist) in understanding dental cutting procedures and in designing adequate experimental methodologies for future studies. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Guidelines for the Investigation of Mediating Variables in Business Research

PubMed Central

Coxe, Stefany; Baraldi, Amanda N.

2013-01-01

Business theories often specify the mediating mechanisms by which a predictor variable affects an outcome variable. In the last 30 years, investigations of mediating processes have become more widespread with corresponding developments in statistical methods to conduct these tests. The purpose of this article is to provide guidelines for mediation studies by focusing on decisions made prior to the research study that affect the clarity of conclusions from a mediation study, the statistical models for mediation analysis, and methods to improve interpretation of mediation results after the research study. Throughout this article, the importance of a program of experimental and observational research for investigating mediating mechanisms is emphasized. PMID:25237213

[Effects of situational and individual variables on critical thinking expression].

PubMed

Tanaka, Yuko; Kusumi, Takashi

2016-04-01

The present study examined when people decide to choose an expression that is based on critical thinking, and how situational and individual variables affect such a decision process. Given a conversation scenario including overgeneralization with two friends, participants decided whether to follow the conversation by a critical-thinking expression or not. The authors controlled purpose and topic as situational variables, and measured critical-thinking ability, critical-thinking disposition, and self-monitoring as individual variables. We conducted an experiment in which the situational variables were counterbalanced in a within-subject design with 60 university students. The results of logistic regression analysis showed differences within individuals in the decision process whether to choose a critical-thinking expression, and that some situational factors and some subscales of the individual measurements were related to the differences.

Neural correlates of processing negative and sexually arousing pictures.

PubMed

Bailey, Kira; West, Robert; Mullaney, Kellie M

2012-01-01

Recent work has questioned whether the negativity bias is a distinct component of affective picture processing. The current study was designed to determine whether there are different neural correlates of processing positive and negative pictures using event-related brain potentials. The early posterior negativity and late positive potential were greatest in amplitude for erotic pictures. Partial Least Squares analysis revealed one latent variable that distinguished erotic pictures from neutral and positive pictures and another that differentiated negative pictures from neutral and positive pictures. The effects of orienting task on the neural correlates of processing negative and erotic pictures indicate that affective picture processing is sensitive to both stimulus-driven, and attentional or decision processes. The current data, together with other recent findings from our laboratory, lead to the suggestion that there are distinct neural correlates of processing negative and positive stimuli during affective picture processing.

Neural Correlates of Processing Negative and Sexually Arousing Pictures

PubMed Central

Bailey, Kira; West, Robert; Mullaney, Kellie M.

2012-01-01

Recent work has questioned whether the negativity bias is a distinct component of affective picture processing. The current study was designed to determine whether there are different neural correlates of processing positive and negative pictures using event-related brain potentials. The early posterior negativity and late positive potential were greatest in amplitude for erotic pictures. Partial Least Squares analysis revealed one latent variable that distinguished erotic pictures from neutral and positive pictures and another that differentiated negative pictures from neutral and positive pictures. The effects of orienting task on the neural correlates of processing negative and erotic pictures indicate that affective picture processing is sensitive to both stimulus-driven, and attentional or decision processes. The current data, together with other recent findings from our laboratory, lead to the suggestion that there are distinct neural correlates of processing negative and positive stimuli during affective picture processing. PMID:23029071

Affective norms of 875 Spanish words for five discrete emotional categories and two emotional dimensions.

PubMed

Hinojosa, J A; Martínez-García, N; Villalba-García, C; Fernández-Folgueiras, U; Sánchez-Carmona, A; Pozo, M A; Montoro, P R

2016-03-01

In the present study, we introduce affective norms for a new set of Spanish words, the Madrid Affective Database for Spanish (MADS), that were scored on two emotional dimensions (valence and arousal) and on five discrete emotional categories (happiness, anger, sadness, fear, and disgust), as well as on concreteness, by 660 Spanish native speakers. Measures of several objective psycholinguistic variables--grammatical class, word frequency, number of letters, and number of syllables--for the words are also included. We observed high split-half reliabilities for every emotional variable and a strong quadratic relationship between valence and arousal. Additional analyses revealed several associations between the affective dimensions and discrete emotions, as well as with some psycholinguistic variables. This new corpus complements and extends prior databases in Spanish and allows for designing new experiments investigating the influence of affective content in language processing under both dimensional and discrete theoretical conceptions of emotion. These norms can be downloaded as supplemental materials for this article from www.dropbox.com/s/o6dpw3irk6utfhy/Hinojosa%20et%20al_Supplementary%20materials.xlsx?dl=0 .

Neuroimaging and Recovery of Language in Aphasia

PubMed Central

Thompson, Cynthia K.; den Ouden, Dirk-Bart

2010-01-01

The use of functional neuroimaging techniques has advanced what is known about the neural mechanisms used to support language processing in aphasia resulting from brain damage. This paper highlights recent findings derived from neuroimaging studies focused on neuroplasticity of language networks, the role of the left and right hemispheres in this process, and studies examining how treatment affects the neurobiology of recovery. We point out variability across studies as well as factors related to this variability, and we emphasize challenges that remain for research. PMID:18957184

Using neutral models to identify constraints on low-severity fire regimes.

Treesearch

Donald McKenzie; Amy E. Hessl; Lara-Karena B. Kellogg

2006-01-01

Climate, topography, fuel loadings, and human activities all affect spatial and temporal patterns of fire occurrence. Because fire is modeled as a stochastic process, for which each fire history is only one realization, a simulation approach is necessary to understand baseline variability, thereby identifying constraints, or forcing functions, that affect fire regimes...

Effect of synthesis variables on tack in urea-formaldehyde resin

Treesearch

R.J. Leicht; C.Y. Hse; R.C. Tang

1988-01-01

The degree of tack-the ability of resin to adhere to another surface under light pressure and over short time- in urea-formaldehyde resin varies throughout the particle board manufacturing process and affects mill maintenance and board quality. A three-part study was conducted to evaluate the effects of certain synthesis variables- molar formaldehyde:urea ratio,...

Motor Activity and Intra-Individual Variability According to Sleep-wake States in Preschool-aged Children with Iron-Deficiency Anemia in Infancy

PubMed Central

Angulo-Barroso, R.M.; Peirano, P.; Algarin, C.; Kaciroti, N.; Lozoff, B.

2013-01-01

Background A chronic or acute insult may affect the regulatory processes that guide motor and behavioral performance, leading to increased intra-individual variability (IIV). Increased variability is often interpreted as an indication of regulatory dysfunction. Iron plays an important role in the regulatory processes of the nervous system and affects motor activity. To our knowledge, no study has examined the long-lasting patterns and IIV of motor activity following iron-deficiency anemia in human infants. Aims This study compared 48-hour motor activity and variability in preschool-aged children with or without iron-deficiency anemia (IDA) in infancy. Methods Motor activity was recorded through actigraphs during two week-days in 47 4-year-old Chilean children (23 former IDA and 24 non-anemic in infancy). All were given oral iron as infants. Sleep-wake states were identified by means of automated software. The frequency of movement units per minute was determined for each waking/sleep state during the individual day and night periods; data were examined in blocks of 15 minutes. Analyses of mean frequency and duration and intra-individual variability were conducted using multivariate mixed models. Results For daytime sleep, former IDA children were more active without a difference in the total duration. They also spent less time awake throughout the individual day period. Motor activity intra-individual variability was higher in former IDA children. Conclusions The findings suggest that IDA in infancy sets the stage for long lasting dysfunction in the neural processes regulating sleep-wake states and spontaneous motor activity patterns. PMID:24041817

Motor activity and intra-individual variability according to sleep-wake states in preschool-aged children with iron-deficiency anemia in infancy.

PubMed

Angulo-Barroso, R M; Peirano, P; Algarin, C; Kaciroti, N; Lozoff, B

2013-12-01

A chronic or acute insult may affect the regulatory processes that guide motor and behavioral performance, leading to increased intra-individual variability (IIV). Increased variability is often interpreted as an indication of regulatory dysfunction. Iron plays an important role in the regulatory processes of the nervous system and affects motor activity. To our knowledge, no study has examined the long-lasting patterns and IIV of motor activity following iron-deficiency anemia in human infants. This study compared 48-h motor activity and variability in preschool-aged children with or without iron-deficiency anemia (IDA) in infancy. Motor activity was recorded through actigraphs during two week-days in 47 4-year-old Chilean children (23 former IDA and 24 non-anemic in infancy). All were given oral iron as infants. Sleep-wake states were identified by means of automated software. The frequency of movement units per minute was determined for each waking/sleep state during the individual day and night periods; data were examined in blocks of 15 min. Analyses of mean frequency and duration and intra-individual variability were conducted using multivariate mixed models. For daytime sleep, former IDA children were more active without a difference in the total duration. They also spent less time awake throughout the individual day period. Motor activity intra-individual variability was higher in former IDA children. The findings suggest that IDA in infancy sets the stage for long lasting dysfunction in the neural processes regulating sleep-wake states and spontaneous motor activity patterns. © 2013.

Ant-mediated ecosystem processes are driven by trophic community structure but mainly by the environment.

PubMed

Salas-Lopez, Alex; Mickal, Houadria; Menzel, Florian; Orivel, Jérôme

2017-01-01

The diversity and functional identity of organisms are known to be relevant to the maintenance of ecosystem processes but can be variable in different environments. Particularly, it is uncertain whether ecosystem processes are driven by complementary effects or by dominant groups of species. We investigated how community structure (i.e., the diversity and relative abundance of biological entities) explains the community-level contribution of Neotropical ant communities to different ecosystem processes in different environments. Ants were attracted with food resources representing six ant-mediated ecosystem processes in four environments: ground and vegetation strata in cropland and forest habitats. The exploitation frequencies of the baits were used to calculate the taxonomic and trophic structures of ant communities and their contribution to ecosystem processes considered individually or in combination (i.e., multifunctionality). We then investigated whether community structure variables could predict ecosystem processes and whether such relationships were affected by the environment. We found that forests presented a greater biodiversity and trophic complementarity and lower dominance than croplands, but this did not affect ecosystem processes. In contrast, trophic complementarity was greater on the ground than on vegetation and was followed by greater resource exploitation levels. Although ant participation in ecosystem processes can be predicted by means of trophic-based indices, we found that variations in community structure and performance in ecosystem processes were best explained by environment. We conclude that determining the extent to which the dominance and complementarity of communities affect ecosystem processes in different environments requires a better understanding of resource availability to different species.

Design of forging process variables under uncertainties

NASA Astrophysics Data System (ADS)

Repalle, Jalaja; Grandhi, Ramana V.

2005-02-01

Forging is a complex nonlinear process that is vulnerable to various manufacturing anomalies, such as variations in billet geometry, billet/die temperatures, material properties, and workpiece and forging equipment positional errors. A combination of these uncertainties could induce heavy manufacturing losses through premature die failure, final part geometric distortion, and reduced productivity. Identifying, quantifying, and controlling the uncertainties will reduce variability risk in a manufacturing environment, which will minimize the overall production cost. In this article, various uncertainties that affect the forging process are identified, and their cumulative effect on the forging tool life is evaluated. Because the forging process simulation is time-consuming, a response surface model is used to reduce computation time by establishing a relationship between the process performance and the critical process variables. A robust design methodology is developed by incorporating reliability-based optimization techniques to obtain sound forging components. A case study of an automotive-component forging-process design is presented to demonstrate the applicability of the method.

Statistical quality control through overall vibration analysis

NASA Astrophysics Data System (ADS)

Carnero, M. ^a. Carmen; González-Palma, Rafael; Almorza, David; Mayorga, Pedro; López-Escobar, Carlos

2010-05-01

The present study introduces the concept of statistical quality control in automotive wheel bearings manufacturing processes. Defects on products under analysis can have a direct influence on passengers' safety and comfort. At present, the use of vibration analysis on machine tools for quality control purposes is not very extensive in manufacturing facilities. Noise and vibration are common quality problems in bearings. These failure modes likely occur under certain operating conditions and do not require high vibration amplitudes but relate to certain vibration frequencies. The vibration frequencies are affected by the type of surface problems (chattering) of ball races that are generated through grinding processes. The purpose of this paper is to identify grinding process variables that affect the quality of bearings by using statistical principles in the field of machine tools. In addition, an evaluation of the quality results of the finished parts under different combinations of process variables is assessed. This paper intends to establish the foundations to predict the quality of the products through the analysis of self-induced vibrations during the contact between the grinding wheel and the parts. To achieve this goal, the overall self-induced vibration readings under different combinations of process variables are analysed using statistical tools. The analysis of data and design of experiments follows a classical approach, considering all potential interactions between variables. The analysis of data is conducted through analysis of variance (ANOVA) for data sets that meet normality and homoscedasticity criteria. This paper utilizes different statistical tools to support the conclusions such as chi squared, Shapiro-Wilks, symmetry, Kurtosis, Cochran, Hartlett, and Hartley and Krushal-Wallis. The analysis presented is the starting point to extend the use of predictive techniques (vibration analysis) for quality control. This paper demonstrates the existence of predictive variables (high-frequency vibration displacements) that are sensible to the processes setup and the quality of the products obtained. Based on the result of this overall vibration analysis, a second paper will analyse self-induced vibration spectrums in order to define limit vibration bands, controllable every cycle or connected to permanent vibration-monitoring systems able to adjust sensible process variables identified by ANOVA, once the vibration readings exceed established quality limits.

How Do Microphysical Processes Influence Large-Scale Precipitation Variability and Extremes?

DOE PAGES

Hagos, Samson; Ruby Leung, L.; Zhao, Chun; ...

2018-02-10

Convection permitting simulations using the Model for Prediction Across Scales-Atmosphere (MPAS-A) are used to examine how microphysical processes affect large-scale precipitation variability and extremes. An episode of the Madden-Julian Oscillation is simulated using MPAS-A with a refined region at 4-km grid spacing over the Indian Ocean. It is shown that cloud microphysical processes regulate the precipitable water (PW) statistics. Because of the non-linear relationship between precipitation and PW, PW exceeding a certain critical value (PWcr) contributes disproportionately to precipitation variability. However, the frequency of PW exceeding PWcr decreases rapidly with PW, so changes in microphysical processes that shift the columnmore » PW statistics relative to PWcr even slightly have large impacts on precipitation variability. Furthermore, precipitation variance and extreme precipitation frequency are approximately linearly related to the difference between the mean and critical PW values. Thus observed precipitation statistics could be used to directly constrain model microphysical parameters as this study demonstrates using radar observations from DYNAMO field campaign.« less

How Do Microphysical Processes Influence Large-Scale Precipitation Variability and Extremes?

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

Hagos, Samson; Ruby Leung, L.; Zhao, Chun

Convection permitting simulations using the Model for Prediction Across Scales-Atmosphere (MPAS-A) are used to examine how microphysical processes affect large-scale precipitation variability and extremes. An episode of the Madden-Julian Oscillation is simulated using MPAS-A with a refined region at 4-km grid spacing over the Indian Ocean. It is shown that cloud microphysical processes regulate the precipitable water (PW) statistics. Because of the non-linear relationship between precipitation and PW, PW exceeding a certain critical value (PWcr) contributes disproportionately to precipitation variability. However, the frequency of PW exceeding PWcr decreases rapidly with PW, so changes in microphysical processes that shift the columnmore » PW statistics relative to PWcr even slightly have large impacts on precipitation variability. Furthermore, precipitation variance and extreme precipitation frequency are approximately linearly related to the difference between the mean and critical PW values. Thus observed precipitation statistics could be used to directly constrain model microphysical parameters as this study demonstrates using radar observations from DYNAMO field campaign.« less

Modeling of laser transmission contour welding process using FEA and DoE

NASA Astrophysics Data System (ADS)

Acherjee, Bappa; Kuar, Arunanshu S.; Mitra, Souren; Misra, Dipten

2012-07-01

In this research, a systematic investigation on laser transmission contour welding process is carried out using finite element analysis (FEA) and design of experiments (DoE) techniques. First of all, a three-dimensional thermal model is developed to simulate the laser transmission contour welding process with a moving heat source. The commercial finite element code ANSYS® multi-physics is used to obtain the numerical results by implementing a volumetric Gaussian heat source, and combined convection-radiation boundary conditions. Design of experiments together with regression analysis is then employed to plan the experiments and to develop mathematical models based on simulation results. Four key process parameters, namely power, welding speed, beam diameter, and carbon black content in absorbing polymer, are considered as independent variables, while maximum temperature at weld interface, weld width, and weld depths in transparent and absorbing polymers are considered as dependent variables. Sensitivity analysis is performed to determine how different values of an independent variable affect a particular dependent variable.

Cognitive switching processes in young people with attention-deficit/hyperactivity disorder.

PubMed

Oades, Robert D; Christiansen, Hanna

2008-01-01

Patients with attention-deficit/hyperactivity disorder (ADHD) can be slow at switching between stimuli, or between sets of stimuli to control behaviour appropriate to changing situations. We examined clinical and experimental parameters that may influence the speed of such processes measured in the trail-making (TMT) and switch-tasks in cases with ADHD combined type, their non-affected siblings and unrelated healthy controls. The latency for completion of the trail-making task controlling for psychomotor processing (TMT-B-A) was longer for ADHD cases, and correlated with Conners' ratings of symptom severity across all subjects. The effect decreased with age. Switch-task responses to questions of "Which number?" and "How many?" between sets of 1/111 or 3/333 elicited differential increases in latency with condition that affected all groups. But there was evidence for increased symptom-related intra-individual variability among the ADHD cases, and across all subjects. Young siblings showed familiality for some measures of TMT and switch-task performance but these were modest. The potential influences of moderator variables on the efficiency of processing stimulus change rather than the speed of processing are discussed.

Taking the pulse of mountains: Ecosystem responses to climatic variability

USGS Publications Warehouse

Fagre, Daniel B.; Peterson, David L.; Hessl, Amy E.

2003-01-01

An integrated program of ecosystem modeling and field studies in the mountains of the Pacific Northwest (U.S.A.) has quantified many of the ecological processes affected by climatic variability. Paleoecological and contemporary ecological data in forest ecosystems provided model parameterization and validation at broad spatial and temporal scales for tree growth, tree regeneration and treeline movement. For subalpine tree species, winter precipitation has a strong negative correlation with growth; this relationship is stronger at higher elevations and west-side sites (which have more precipitation). Temperature affects tree growth at some locations with respect to length of growing season (spring) and severity of drought at drier sites (summer). Furthermore, variable but predictable climate-growth relationships across elevation gradients suggest that tree species respond differently to climate at different locations, making a uniform response of these species to future climatic change unlikely. Multi-decadal variability in climate also affects ecosystem processes. Mountain hemlock growth at high-elevation sites is negatively correlated with winter snow depth and positively correlated with the winter Pacific Decadal Oscillation (PDO) index. At low elevations, the reverse is true. Glacier mass balance and fire severity are also linked to PDO. Rapid establishment of trees in subalpine ecosystems during this century is increasing forest cover and reducing meadow cover at many subalpine locations in the western U.S.A. and precipitation (snow depth) is a critical variable regulating conifer expansion. Lastly, modeling potential future ecosystem conditions suggests that increased climatic variability will result in increasing forest fire size and frequency, and reduced net primary productivity in drier, east-side forest ecosystems. As additional empirical data and modeling output become available, we will improve our ability to predict the effects of climatic change across a broad range of climates and mountain ecosystems in the northwestern U.S.A.

The rise of global warming skepticism: exploring affective image associations in the United States over time.

PubMed

Smith, Nicholas; Leiserowitz, Anthony

2012-06-01

This article explores how affective image associations to global warming have changed over time. Four nationally representative surveys of the American public were conducted between 2002 and 2010 to assess public global warming risk perceptions, policy preferences, and behavior. Affective images (positive or negative feelings and cognitive representations) were collected and content analyzed. The results demonstrate a large increase in "naysayer" associations, indicating extreme skepticism about the issue of climate change. Multiple regression analyses found that holistic affect and "naysayer" associations were more significant predictors of global warming risk perceptions than cultural worldviews or sociodemographic variables, including political party and ideology. The results demonstrate the important role affective imagery plays in judgment and decision-making processes, how these variables change over time, and how global warming is currently perceived by the American public. © 2012 Society for Risk Analysis.

Approximate reduction of linear population models governed by stochastic differential equations: application to multiregional models.

PubMed

Sanz, Luis; Alonso, Juan Antonio

2017-12-01

In this work we develop approximate aggregation techniques in the context of slow-fast linear population models governed by stochastic differential equations and apply the results to the treatment of populations with spatial heterogeneity. Approximate aggregation techniques allow one to transform a complex system involving many coupled variables and in which there are processes with different time scales, by a simpler reduced model with a fewer number of 'global' variables, in such a way that the dynamics of the former can be approximated by that of the latter. In our model we contemplate a linear fast deterministic process together with a linear slow process in which the parameters are affected by additive noise, and give conditions for the solutions corresponding to positive initial conditions to remain positive for all times. By letting the fast process reach equilibrium we build a reduced system with a lesser number of variables, and provide results relating the asymptotic behaviour of the first- and second-order moments of the population vector for the original and the reduced system. The general technique is illustrated by analysing a multiregional stochastic system in which dispersal is deterministic and the rate growth of the populations in each patch is affected by additive noise.

How emotions affect eating: a five-way model.

PubMed

Macht, Michael

2008-01-01

Despite the importance of affective processes in eating behaviour, it remains difficult to predict how emotions affect eating. Emphasizing individual differences, previous research did not pay full attention to the twofold variability of emotion-induced changes of eating (variability across both individuals and emotions). By contrast, the present paper takes into account both individual characteristics and emotion features, and specifies five classes of emotion-induced changes of eating: (1) emotional control of food choice, (2) emotional suppression of food intake, (3) impairment of cognitive eating controls, (4) eating to regulate emotions, and (5) emotion-congruent modulation of eating. These classes are distinguished by antecedent conditions, eating responses and mediating mechanisms. They point to basic functional principles underlying the relations between emotions and biologically based motives: interference, concomitance and regulation. Thus, emotion-induced changes of eating can be a result of interference of eating by emotions, a by-product of emotions, and a consequence of regulatory processes (i.e., emotions may regulate eating, and eating may regulate emotions).

Analysis of Quality and Output of Entrepreneurship in the Field of Refractionist Optician

NASA Astrophysics Data System (ADS)

Wesnita, A.; Dewi, M.

2018-02-01

The launching of the Asean Economic Community (AEC) caused a rivalry on the exchange of the work, especially workers who are involved in the sector of specific expertise that increased sharply. The solution offered is through the implementation of entrepreneurship learning, but despite entrepreneurship courses have been given to students since 2007, data from the last three years states only 21% of graduates of Refractionist Optician Academy in Padang, Indonesia, which became entrepreneurs in the fields of optics and eye health. Therefore, there needs to be an assessment whether the 5 variables of learning process that has been done three variables affect the output quality of learning entrepreneurship. This study has a quantitative method to determine the effect on output quality of the learning process of learning through regression analysis, test t, R2 and the percentage of contribution. The population consist of 121 students and the sample is 54 people. The study states that the academic skills of entrepreneurship is influenced by four variables of learning process, personnel skills of entrepreneurship is not influenced by any learning variable process, and social skills of entrepreneurship is influenced by three variables learning process.

Colour-induced relationship between affect and reaching kinematics during a goal-directed aiming task.

PubMed

Williams, Camille K; Grierson, Lawrence E M; Carnahan, Heather

2011-08-01

A link between affect and action has been supported by the discovery that threat information is prioritized through an action-centred pathway--the dorsal visual stream. Magnocellular afferents, which originate from the retina and project to dorsal stream structures, are suppressed by exposure to diffuse red light, which diminishes humans' perception of threat-based images. In order to explore the role of colour in the relationship between affect and action, participants donned different pairs of coloured glasses (red, yellow, green, blue and clear) and completed Positive and Negative Affect Scale questionnaires as well as a series of target-directed aiming movements. Analyses of affect scores revealed a significant main effect for affect valence and a significant interaction between colour and valence: perceived positive affect was significantly smaller for the red condition. Kinematic analyses of variable error in the primary movement direction and Pearson correlation analyses between the displacements travelled prior to and following peak velocity indicated reduced accuracy and application of online control processes while wearing red glasses. Variable error of aiming was also positively and significantly correlated with negative affect scores under the red condition. These results suggest that only red light modulates the affect-action link by suppressing magnocellular activity, which disrupts visual processing for movement control. Furthermore, previous research examining the effect of the colour red on psychomotor tasks and perceptual acceleration of threat-based imagery suggest that stimulus-driven motor performance tasks requiring online control may be particularly susceptible to this effect.

Which Sweetener Is Best for Yeast? An Inquiry-Based Learning for Conceptual Change

ERIC Educational Resources Information Center

Cherif, Abour H.; Siuda, JoElla E.; Kassem, Sana; Gialamas, Stefanos; Movahedzadeh, Farahnaz

2017-01-01

One way to help students understand the scientific inquiry process, and how it applies in investigative research, is to involve them in scientific investigation. An example of this would be letting them come to their own understanding of how different variables (e.g., starting products) can affect outcomes (e.g., variable quality end products)…

Estuarine fish communities respond to climate variability over both river and ocean basins

USGS Publications Warehouse

Feyrer, Frederick V.; Cloern, James E.; Brown, Larry R.; Fish, Maxfield; Hieb, Kathryn; Baxter, Randall

2015-01-01

Estuaries are dynamic environments at the land–sea interface that are strongly affected by interannual climate variability. Ocean–atmosphere processes propagate into estuaries from the sea, and atmospheric processes over land propagate into estuaries from watersheds. We examined the effects of these two separate climate-driven processes on pelagic and demersal fish community structure along the salinity gradient in the San Francisco Estuary, California, USA. A 33-year data set (1980–2012) on pelagic and demersal fishes spanning the freshwater to marine regions of the estuary suggested the existence of five estuarine salinity fish guilds: limnetic (salinity = 0–1), oligohaline (salinity = 1–12), mesohaline (salinity = 6–19), polyhaline (salinity = 19–28), and euhaline (salinity = 29–32). Climatic effects propagating from the adjacent Pacific Ocean, indexed by the North Pacific Gyre Oscillation (NPGO), affected demersal and pelagic fish community structure in the euhaline and polyhaline guilds. Climatic effects propagating over land, indexed as freshwater outflow from the watershed (OUT), affected demersal and pelagic fish community structure in the oligohaline, mesohaline, polyhaline, and euhaline guilds. The effects of OUT propagated further down the estuary salinity gradient than the effects of NPGO that propagated up the estuary salinity gradient, exemplifying the role of variable freshwater outflow as an important driver of biotic communities in river-dominated estuaries. These results illustrate how unique sources of climate variability interact to drive biotic communities and, therefore, that climate change is likely to be an important driver in shaping the future trajectory of biotic communities in estuaries and other transitional habitats.

Estuarine fish communities respond to climate variability over both river and ocean basins.

PubMed

Feyrer, Frederick; Cloern, James E; Brown, Larry R; Fish, Maxfield A; Hieb, Kathryn A; Baxter, Randall D

2015-10-01

Estuaries are dynamic environments at the land-sea interface that are strongly affected by interannual climate variability. Ocean-atmosphere processes propagate into estuaries from the sea, and atmospheric processes over land propagate into estuaries from watersheds. We examined the effects of these two separate climate-driven processes on pelagic and demersal fish community structure along the salinity gradient in the San Francisco Estuary, California, USA. A 33-year data set (1980-2012) on pelagic and demersal fishes spanning the freshwater to marine regions of the estuary suggested the existence of five estuarine salinity fish guilds: limnetic (salinity = 0-1), oligohaline (salinity = 1-12), mesohaline (salinity = 6-19), polyhaline (salinity = 19-28), and euhaline (salinity = 29-32). Climatic effects propagating from the adjacent Pacific Ocean, indexed by the North Pacific Gyre Oscillation (NPGO), affected demersal and pelagic fish community structure in the euhaline and polyhaline guilds. Climatic effects propagating over land, indexed as freshwater outflow from the watershed (OUT), affected demersal and pelagic fish community structure in the oligohaline, mesohaline, polyhaline, and euhaline guilds. The effects of OUT propagated further down the estuary salinity gradient than the effects of NPGO that propagated up the estuary salinity gradient, exemplifying the role of variable freshwater outflow as an important driver of biotic communities in river-dominated estuaries. These results illustrate how unique sources of climate variability interact to drive biotic communities and, therefore, that climate change is likely to be an important driver in shaping the future trajectory of biotic communities in estuaries and other transitional habitats. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

The Climate Variability & Predictability (CVP) Program at NOAA - Observing and Understanding Processes Affecting the Propagation of Intraseasonal Oscillations in the Maritime Continent Region

NASA Astrophysics Data System (ADS)

Lucas, S. E.

2017-12-01

The Climate Variability & Predictability (CVP) Program supports research aimed at providing process-level understanding of the climate system through observation, modeling, analysis, and field studies. This vital knowledge is needed to improve climate models and predictions so that scientists can better anticipate the impacts of future climate variability and change. To achieve its mission, the CVP Program supports research carried out at NOAA and other federal laboratories, NOAA Cooperative Institutes, and academic institutions. The Program also coordinates its sponsored projects with major national and international scientific bodies including the World Climate Research Programme (WCRP), the International and U.S. Climate Variability and Predictability (CLIVAR/US CLIVAR) Program, and the U.S. Global Change Research Program (USGCRP). The CVP program sits within NOAA's Climate Program Office (http://cpo.noaa.gov/CVP). In 2017, the CVP Program had a call for proposals focused on observing and understanding processes affecting the propagation of intraseasonal oscillations in the Maritime Continent region. This poster will present the recently funded CVP projects, the expected scientific outcomes, the geographic areas of their work in the Maritime Continent region, and the collaborations with the Office of Naval Research, Indonesian Agency for Meteorology, Climatology and Geophysics (BMKG), Japan Agency for Marine-Earth Science and Technology (JAMSTEC) and other partners.

When time affects space: Dispersal ability and extreme weather events determine metacommunity organization in marine sediments.

PubMed

Corte, Guilherme N; Gonçalves-Souza, Thiago; Checon, Helio H; Siegle, Eduardo; Coleman, Ross A; Amaral, A Cecília Z

2018-05-01

Community ecology has traditionally assumed that the distribution of species is mainly influenced by environmental processes. There is, however, growing evidence that environmental (habitat characteristics and biotic interactions) and spatial processes (factors that affect a local assemblage regardless of environmental conditions - typically related to dispersal and movement of species) interactively shape biological assemblages. A metacommunity, which is a set of local assemblages connected by dispersal of individuals, is spatial in nature and can be used as a straightforward approach for investigating the interactive and independent effects of both environmental and spatial processes. Here, we examined (i) how environmental and spatial processes affect the metacommunity organization of marine macroinvertebrates inhabiting the intertidal sediments of a biodiverse coastal ecosystem; (ii) whether the influence of these processes is constant through time or is affected by extreme weather events (storms); and (iii) whether the relative importance of these processes depends on the dispersal abilities of organisms. We found that macrobenthic assemblages are influenced by each of environmental and spatial variables; however, spatial processes exerted a stronger role. We also found that this influence changes through time and is modified by storms. Moreover, we observed that the influence of environmental and spatial processes varies according to the dispersal capabilities of organisms. More effective dispersers (i.e., species with planktonic larvae) are more affected by spatial processes whereas environmental variables had a stronger effect on weaker dispersers (i.e. species with low motility in larval and adult stages). These findings highlight that accounting for spatial processes and differences in species life histories is essential to improve our understanding of species distribution and coexistence patterns in intertidal soft-sediments. Furthermore, it shows that storms modify the structure of coastal assemblages. Given that the influence of spatial and environmental processes is not consistent through time, it is of utmost importance that future studies replicate sampling over different periods so the influence of temporal and stochastic factors on macrobenthic metacommunities can be better understood. Copyright © 2018 Elsevier Ltd. All rights reserved.

Trends in Solidification Grain Size and Morphology for Additive Manufacturing of Ti-6Al-4V

NASA Astrophysics Data System (ADS)

Gockel, Joy; Sheridan, Luke; Narra, Sneha P.; Klingbeil, Nathan W.; Beuth, Jack

2017-12-01

Metal additive manufacturing (AM) is used for both prototyping and production of final parts. Therefore, there is a need to predict and control the microstructural size and morphology. Process mapping is an approach that represents AM process outcomes in terms of input variables. In this work, analytical, numerical, and experimental approaches are combined to provide a holistic view of trends in the solidification grain structure of Ti-6Al-4V across a wide range of AM process input variables. The thermal gradient is shown to vary significantly through the depth of the melt pool, which precludes development of fully equiaxed microstructure throughout the depth of the deposit within any practical range of AM process variables. A strategy for grain size control is demonstrated based on the relationship between melt pool size and grain size across multiple deposit geometries, and additional factors affecting grain size are discussed.

Bioremediation techniques applied to aqueous media contaminated with mercury.

PubMed

Velásquez-Riaño, Möritz; Benavides-Otaya, Holman D

2016-12-01

In recent years, the environmental and human health impacts of mercury contamination have driven the search for alternative, eco-efficient techniques different from the traditional physicochemical methods for treating this metal. One of these alternative processes is bioremediation. A comprehensive analysis of the different variables that can affect this process is presented. It focuses on determining the effectiveness of different techniques of bioremediation, with a specific consideration of three variables: the removal percentage, time needed for bioremediation and initial concentration of mercury to be treated in an aqueous medium.

An Examination of Individual Level Factors in Stress and Coping Processes: Perspectives of Chinese International Students in the United States

ERIC Educational Resources Information Center

Yan, Kun; Berliner, David C.

2011-01-01

No empirical research has focused solely upon understanding the stress and coping processes of Chinese international students in the United States. This qualitative inquiry examines the individual-level variables that affect the stress-coping process of Chinese international students and how they conceptualize and adapt to their stress at an…

Optimal Mixtures of Test Types in Paired-Associate Learning (Sensory Information Processing). Final Report.

ERIC Educational Resources Information Center

Wolford, George

Seven experiments were run to determine the precise nature of some of the variables which affect the processing of short-term visual information. In particular, retinal location, report order, processing order, lateral masking, and redundancy were studied along with the nature of the confusion errors which are made in the full report procedure.…

Quality by Design approach for studying the impact of formulation and process variables on product quality of oral disintegrating films.

PubMed

Mazumder, Sonal; Pavurala, Naresh; Manda, Prashanth; Xu, Xiaoming; Cruz, Celia N; Krishnaiah, Yellela S R

2017-07-15

The present investigation was carried out to understand the impact of formulation and process variables on the quality of oral disintegrating films (ODF) using Quality by Design (QbD) approach. Lamotrigine (LMT) was used as a model drug. Formulation variable was plasticizer to film former ratio and process variables were drying temperature, air flow rate in the drying chamber, drying time and wet coat thickness of the film. A Definitive Screening Design of Experiments (DoE) was used to identify and classify the critical formulation and process variables impacting critical quality attributes (CQA). A total of 14 laboratory-scale DoE formulations were prepared and evaluated for mechanical properties (%elongation at break, yield stress, Young's modulus, folding endurance) and other CQA (dry thickness, disintegration time, dissolution rate, moisture content, moisture uptake, drug assay and drug content uniformity). The main factors affecting mechanical properties were plasticizer to film former ratio and drying temperature. Dissolution rate was found to be sensitive to air flow rate during drying and plasticizer to film former ratio. Data were analyzed for elucidating interactions between different variables, rank ordering the critical materials attributes (CMA) and critical process parameters (CPP), and for providing a predictive model for the process. Results suggested that plasticizer to film former ratio and process controls on drying are critical to manufacture LMT ODF with the desired CQA. Published by Elsevier B.V.

Assessing the effects of multiple stressors on the functioning of Mediterranean rivers using poplar wood breakdown.

PubMed

Aristi, Ibon; Díez, Jose Ramon; Larrañaga, Aitor; Navarro-Ortega, Alícia; Barceló, Damià; Elosegi, Arturo

2012-12-01

Mediterranean rivers in the Iberian Peninsula are being increasingly affected by human activities, which threaten their ecological status. A clear picture of how do these multiple stressors affect river ecosystem functioning is still lacking. We addressed this question by measuring a key ecosystem process, namely breakdown of organic matter, at 66 sites distributed across Mediterranean Spain. We performed breakdown experiments by measuring the mass lost by wood sticks for 54 to 106 days. Additionally, we gathered data on physico-chemical, biological and geomorphological characteristics of study sites. Study sites spanned a broad range of environmental characteristics and breakdown rates varied fiftyfold across sites. No clear geographic patterns were found between or within basins. 90th quantile regressions performed to link breakdown rates with environmental characteristics included the following 7 variables in the model, in decreasing order of importance: altitude, water content in phosphorus, catchment area, toxicity, invertebrate-based biotic index, riparian buffer width, and diatom-based quality index. Breakdown rate was systematically low in high-altitude rivers with few human impacts, but showed a high variability in areas affected by human activity. This increase in variability is the result of the influence of multiple stressors acting simultaneously, as some of these can promote whereas others slow down the breakdown of organic matter. Therefore, stick breakdown gives information on the intensity of a key ecosystem process, which would otherwise be very difficult to predict based on environmental variables. Copyright © 2012 Elsevier B.V. All rights reserved.

Negative affect variability and adolescent self-medication: The role of the peer context.

PubMed

Shadur, Julia M; Hussong, Andrea M; Haroon, Maleeha

2015-11-01

Findings in the literature show mixed support for adolescent self-medication. Following recent reformulations of the self-medication hypothesis, we tested within-person effects of daily fluctuations in sadness and worry on daily substance use, and explored the moderating role of the peer context on self-medication. We hypothesized that greater daily fluctuations in mood would predict greater daily substance use, and lower levels of peer social support and higher levels of peer drug use would further increase this risk. Experience sampling methods captured within-person daily variations in mood and substance use over 21 days among 73 adolescents. An observational coding system was employed to characterize enacted peer social support. Multilevel modeling was used to parse between- versus within-person differences in risk for daily substance use. Greater within-person daily fluctuations in feelings of worry (but not sadness) significantly predicted increased daily substance use, consistent with self-medication. Moreover, greater daily fluctuations in negative affect were a stronger predictor of daily use than total level of daily negative affect. Peer social support moderated this relationship such that those with more supportive friendships were less likely to engage in self-medication. This is the first reported study to examine within-person processes of adolescent self-medication related to daily variability in mood and the peer context. Adolescent self-medication processes appear to differ depending on the type of negative affect and whether daily affective experiences are chronic or fluctuating, suggesting that the affective processes that cue adolescents to engage in substance use are quite nuanced. © 2015 Australasian Professional Society on Alcohol and other Drugs.

The sequential pathway between trauma-related symptom severity and cognitive-based smoking processes through perceived stress and negative affect reduction expectancies among trauma exposed smokers.

PubMed

Garey, Lorra; Cheema, Mina K; Otal, Tanveer K; Schmidt, Norman B; Neighbors, Clayton; Zvolensky, Michael J

2016-10-01

Smoking rates are markedly higher among trauma-exposed individuals relative to non-trauma-exposed individuals. Extant work suggests that both perceived stress and negative affect reduction smoking expectancies are independent mechanisms that link trauma-related symptoms and smoking. Yet, no work has examined perceived stress and negative affect reduction smoking expectancies as potential explanatory variables for the relation between trauma-related symptom severity and smoking in a sequential pathway model. Methods The present study utilized a sample of treatment-seeking, trauma-exposed smokers (n = 363; 49.0% female) to examine perceived stress and negative affect reduction expectancies for smoking as potential sequential explanatory variables linking trauma-related symptom severity and nicotine dependence, perceived barriers to smoking cessation, and severity of withdrawal-related problems and symptoms during past quit attempts. As hypothesized, perceived stress and negative affect reduction expectancies had a significant sequential indirect effect on trauma-related symptom severity and criterion variables. Findings further elucidate the complex pathways through which trauma-related symptoms contribute to smoking behavior and cognitions, and highlight the importance of addressing perceived stress and negative affect reduction expectancies in smoking cessation programs among trauma-exposed individuals. (Am J Addict 2016;25:565-572). © 2016 American Academy of Addiction Psychiatry.

Paleodust variability since the Last Glacial Maximum and implications for iron inputs to the ocean

NASA Astrophysics Data System (ADS)

Albani, S.; Mahowald, N. M.; Murphy, L. N.; Raiswell, R.; Moore, J. K.; Anderson, R. F.; McGee, D.; Bradtmiller, L. I.; Delmonte, B.; Hesse, P. P.; Mayewski, P. A.

2016-04-01

Changing climate conditions affect dust emissions and the global dust cycle, which in turn affects climate and biogeochemistry. In this study we use observationally constrained model reconstructions of the global dust cycle since the Last Glacial Maximum, combined with different simplified assumptions of atmospheric and sea ice processing of dust-borne iron, to provide estimates of soluble iron deposition to the oceans. For different climate conditions, we discuss uncertainties in model-based estimates of atmospheric processing and dust deposition to key oceanic regions, highlighting the large degree of uncertainty of this important variable for ocean biogeochemistry and the global carbon cycle. We also show the role of sea ice acting as a time buffer and processing agent, which results in a delayed and pulse-like soluble iron release into the ocean during the melting season, with monthly peaks up to ~17 Gg/month released into the Southern Oceans during the Last Glacial Maximum (LGM).

Trace metal pyritization variability in response to mangrove soil aerobic and anaerobic oxidation processes.

PubMed

Machado, W; Borrelli, N L; Ferreira, T O; Marques, A G B; Osterrieth, M; Guizan, C

2014-02-15

The degree of iron pyritization (DOP) and degree of trace metal pyritization (DTMP) were evaluated in mangrove soil profiles from an estuarine area located in Rio de Janeiro (SE Brazil). The soil pH was negatively correlated with redox potential (Eh) and positively correlated with DOP and DTMP of some elements (Mn, Cu and Pb), suggesting that pyrite oxidation generated acidity and can affect the importance of pyrite as a trace metal-binding phase, mainly in response to spatial variability in tidal flooding. Besides these aerobic oxidation effects, results from a sequential extraction analyses of reactive phases evidenced that Mn oxidized phase consumption in reaction with pyrite can be also important to determine the pyritization of trace elements. Cumulative effects of these aerobic and anaerobic oxidation processes were evidenced as factors affecting the capacity of mangrove soils to act as a sink for trace metals through pyritization processes. Copyright © 2013 Elsevier Ltd. All rights reserved.

Affective functioning among early adolescents at high and low familial risk for depression and their mothers: A focus on individual and transactional processes across contexts

PubMed Central

McMakin, Dana L.; Burkhouse, Katie L.; Olino, Thomas M.; Siegle, Greg J.; Dahl, Ronald E.; Silk, Jennifer S.

2013-01-01

This study aimed to characterize affective functioning in families of youth at high familial risk for depression, with particular attention to features of affective functioning that appear to be critical to adaptive functioning but have been underrepresented in prior research including: positive and negative affect across multiple contexts, individual and transactional processes, and affective flexibility. Interactions among early adolescents (ages 9-14) and their mothers were coded for affective behaviors across both positive and negative contexts. Primary analyses compared never-depressed youth at high (n=44) and low (n=57) familial risk for depression. The high risk group showed a relatively consistent pattern for low positive affect across negative and positive contexts at both the individual and transactional level. In contrast to prior studies focusing on negative affect that did not support disruptions in negative affect, the data from this study suggest variability by context: (i.e. increased negativity in a positive, but not negative, context) and individual vs. transactional processes (e.g., negative escalation). Findings are discussed in concert with attention to affect flexibility, contextual and transactional factors. PMID:21744058

Effect of processing on recovery and variability associated with immunochemical analytical methods for multiple allergens in a single matrix: sugar cookies.

PubMed

Khuda, Sefat; Slate, Andrew; Pereira, Marion; Al-Taher, Fadwa; Jackson, Lauren; Diaz-Amigo, Carmen; Bigley, Elmer C; Whitaker, Thomas; Williams, Kristina M

2012-05-02

Among the major food allergies, peanut, egg, and milk are the most common. The immunochemical detection of food allergens depends on various factors, such as the food matrix and processing method, which can affect allergen conformation and extractability. This study aimed to (1) develop matrix-specific incurred reference materials for allergen testing, (2) determine whether multiple allergens in the same model food can be simultaneously detected, and (3) establish the effect of processing on reference material stability and allergen detection. Defatted peanut flour, whole egg powder, and spray-dried milk were added to cookie dough at seven incurred levels before baking. Allergens were measured using five commercial enzyme-linked immunosorbent assay (ELISA) kits. All kits showed decreased recovery of all allergens after baking. Analytical coefficients of variation for most kits increased with baking time, but decreased with incurred allergen level. Thus, food processing negatively affects the recovery and variability of peanut, egg, and milk detection in a sugar cookie matrix when using immunochemical methods.

Does Gender Play a Role in the Assessment of Oral Proficiency?

ERIC Educational Resources Information Center

Motallebzadeh, Khalil; Nematizadeh, Shaahin

2011-01-01

Gender has been a controversial issue which affects the language learning process. McNamara (1996) has proposed that there are some variables affecting second language performance one of which is sex. In much the same way, it has been reported that gender plays a role in the area of language testing (Brown, 2003; Lumley & O'Sullivan, 2005;…

Depressive Symptoms Affect Working Memory in Healthy Older Adult Hispanics.

PubMed

Salazar-Villanea, Monica; Liebmann, Edward; Garnier-Villarreal, Mauricio; Montenegro-Montenegro, Esteban; Johnson, David K

2015-10-01

Low and middle income nations will experience an unprecedented growth of the elderly population and subsequent increase in age-related neurological disorders. Worldwide prevalence and incidence of all-types of neurological disorders with serious mental health complications will increase with life expectancy across the globe. One-in- ten individuals over 75 has at least moderate cognitive impairment. Prevalence of cognitive impairment doubles every 5 years thereafter. Latin America's population of older adult's 65 years and older is growing rapidly, yet little is known about cognitive aging among healthy older Latinos. Clinically significant depressive symptomatology is common among community-dwelling older adults and is associated with deficits across multiple cognitive domains, however much of the literature has not modeled the unique effects of depression distinct from negative and low positive affect. Our objective was to understand how mental health affects cognitive health in healthy aging Latinos. The present study used confirmatory factor analysis (CFA) and structural equation modeling (SEM) to examine the relative effects of Negative Affect, Positive Affect and Geriatric Depression on Verbal Memory, Verbal Reasoning, Processing Speed, and Working Memory in healthy aging Latinos. Data was collected from a sample of healthy community dwelling older adults living in San Jose, Costa Rica. Modeling of latent variables attenuated error and improved measurement reliability of cognition, affect, and depression variables. Costa Ricans enjoy a notoriety for being much happier than US citizens and are renowned as one of the happiest nations in the world in global surveys. This was born out in these data. Costa Rican affective profiles differed substantively from US profiles. Levels of negative affect and depression were similar to US samples, but their levels of positive affect were much higher. Cognitive performance of these Costa Rican older adults was similar to US-age and education matched peers. CFA and SEM found that increased depressive symptomatology had deleterious effects on Working Memory made up of subtest scores sampling simple attention and vigilance for numbers. Verbal Memory, Verbal Reasoning, and Processing Speed were not affected by self-reported Positive Affect, Negative Affect or Depressive symptoms. Costa Rican older adults were happy, as evidenced by the high ratio of positive affect to relatively low negative affect. Thus, we were somewhat surprised to find that depressive symptoms were selectively correlated to decrements in working memory and that negative and positive affect contributed negligible amounts of variance to any of the cognitive factors. Because of the methodological rigor of latent variable analysis, these results are very specific. The Working Memory factor is not contaminated with Speed of Processing or other measured cognitive factors. Likewise, the measured Geriatric Depression represents symptoms that are richly cognitive, not overtly affective.

What controls channel form in steep mountain streams?

NASA Astrophysics Data System (ADS)

Palucis, M. C.; Lamb, M. P.

2017-07-01

Steep mountain streams have channel morphologies that transition from alternate bar to step-pool to cascade with increasing bed slope, which affect stream habitat, flow resistance, and sediment transport. Experimental and theoretical studies suggest that alternate bars form under large channel width-to-depth ratios, step-pools form in near supercritical flow or when channel width is narrow compared to bed grain size, and cascade morphology is related to debris flows. However, the connection between these process variables and bed slope—the apparent dominant variable for natural stream types—is unclear. Combining field data and theory, we find that certain bed slopes have unique channel morphologies because the process variables covary systematically with bed slope. Multiple stable states are predicted for other ranges in bed slope, suggesting that a competition of underlying processes leads to the emergence of the most stable channel form.

Latent variable modeling to analyze the effects of process parameters on the dissolution of paracetamol tablet

PubMed Central

Sun, Fei; Xu, Bing; Zhang, Yi; Dai, Shengyun; Shi, Xinyuan; Qiao, Yanjiang

2017-01-01

ABSTRACT The dissolution is one of the critical quality attributes (CQAs) of oral solid dosage forms because it relates to the absorption of drug. In this paper, the influence of raw materials, granules and process parameters on the dissolution of paracetamol tablet was analyzed using latent variable modeling methods. The variability in raw materials and granules was understood based on the principle component analysis (PCA), respectively. A multi-block partial least squares (MBPLS) model was used to determine the critical factors affecting the dissolution. The results showed that the binder amount, the post granulation time, the API content in granule, the fill depth and the punch tip separation distance were the critical factors with variable importance in the projection (VIP) values larger than 1. The importance of each unit of the whole process was also ranked using the block importance in the projection (BIP) index. It was concluded that latent variable models (LVMs) were very useful tools to extract information from the available data and improve the understanding on dissolution behavior of paracetamol tablet. The obtained LVMs were also helpful to propose the process design space and to design control strategies in the further research. PMID:27689242

Six Sigma methods applied to cryogenic coolers assembly line

NASA Astrophysics Data System (ADS)

Ventre, Jean-Marc; Germain-Lacour, Michel; Martin, Jean-Yves; Cauquil, Jean-Marc; Benschop, Tonny; Griot, René

2009-05-01

Six Sigma method have been applied to manufacturing process of a rotary Stirling cooler: RM2. Name of the project is NoVa as main goal of the Six Sigma approach is to reduce variability (No Variability). Project has been based on the DMAIC guideline following five stages: Define, Measure, Analyse, Improve, Control. Objective has been set on the rate of coolers succeeding performance at first attempt with a goal value of 95%. A team has been gathered involving people and skills acting on the RM2 manufacturing line. Measurement System Analysis (MSA) has been applied to test bench and results after R&R gage show that measurement is one of the root cause for variability in RM2 process. Two more root causes have been identified by the team after process mapping analysis: regenerator filling factor and cleaning procedure. Causes for measurement variability have been identified and eradicated as shown by new results from R&R gage. Experimental results show that regenerator filling factor impacts process variability and affects yield. Improved process haven been set after new calibration process for test bench, new filling procedure for regenerator and an additional cleaning stage have been implemented. The objective for 95% coolers succeeding performance test at first attempt has been reached and kept for a significant period. RM2 manufacturing process is now managed according to Statistical Process Control based on control charts. Improvement in process capability have enabled introduction of sample testing procedure before delivery.

Large-scale climatic anomalies affect marine predator foraging behaviour and demography.

PubMed

Bost, Charles A; Cotté, Cedric; Terray, Pascal; Barbraud, Christophe; Bon, Cécile; Delord, Karine; Gimenez, Olivier; Handrich, Yves; Naito, Yasuhiko; Guinet, Christophe; Weimerskirch, Henri

2015-10-27

Determining the links between the behavioural and population responses of wild species to environmental variations is critical for understanding the impact of climate variability on ecosystems. Using long-term data sets, we show how large-scale climatic anomalies in the Southern Hemisphere affect the foraging behaviour and population dynamics of a key marine predator, the king penguin. When large-scale subtropical dipole events occur simultaneously in both subtropical Southern Indian and Atlantic Oceans, they generate tropical anomalies that shift the foraging zone southward. Consequently the distances that penguins foraged from the colony and their feeding depths increased and the population size decreased. This represents an example of a robust and fast impact of large-scale climatic anomalies affecting a marine predator through changes in its at-sea behaviour and demography, despite lack of information on prey availability. Our results highlight a possible behavioural mechanism through which climate variability may affect population processes.

Large-scale climatic anomalies affect marine predator foraging behaviour and demography

NASA Astrophysics Data System (ADS)

Bost, Charles A.; Cotté, Cedric; Terray, Pascal; Barbraud, Christophe; Bon, Cécile; Delord, Karine; Gimenez, Olivier; Handrich, Yves; Naito, Yasuhiko; Guinet, Christophe; Weimerskirch, Henri

2015-10-01

Determining the links between the behavioural and population responses of wild species to environmental variations is critical for understanding the impact of climate variability on ecosystems. Using long-term data sets, we show how large-scale climatic anomalies in the Southern Hemisphere affect the foraging behaviour and population dynamics of a key marine predator, the king penguin. When large-scale subtropical dipole events occur simultaneously in both subtropical Southern Indian and Atlantic Oceans, they generate tropical anomalies that shift the foraging zone southward. Consequently the distances that penguins foraged from the colony and their feeding depths increased and the population size decreased. This represents an example of a robust and fast impact of large-scale climatic anomalies affecting a marine predator through changes in its at-sea behaviour and demography, despite lack of information on prey availability. Our results highlight a possible behavioural mechanism through which climate variability may affect population processes.

Mechanisms of the 40-70 Day Variability in the Yucatan Channel Volume Transport

NASA Astrophysics Data System (ADS)

van Westen, René M.; Dijkstra, Henk A.; Klees, Roland; Riva, Riccardo E. M.; Slobbe, D. Cornelis; van der Boog, Carine G.; Katsman, Caroline A.; Candy, Adam S.; Pietrzak, Julie D.; Zijlema, Marcel; James, Rebecca K.; Bouma, Tjeerd J.

2018-02-01

The Yucatan Channel connects the Caribbean Sea with the Gulf of Mexico and is the main outflow region of the Caribbean Sea. Moorings in the Yucatan Channel show high-frequent variability in kinetic energy (50-100 days) and transport (20-40 days), but the physical mechanisms controlling this variability are poorly understood. In this study, we show that the short-term variability in the Yucatan Channel transport has an upstream origin and arises from processes in the North Brazil Current. To establish this connection, we use data from altimetry and model output from several high resolution global models. A significant 40-70 day variability is found in the sea surface height in the North Brazil Current retroflection region with a propagation toward the Lesser Antilles. The frequency of variability is generated by intrinsic processes associated with the shedding of eddies, rather than by atmospheric forcing. This sea surface height variability is able to pass the Lesser Antilles, it propagates westward with the background ocean flow in the Caribbean Sea and finally affects the variability in the Yucatan Channel volume transport.

Impact of Timed Reading on Comprehension and Speed: A Study on Turkish EFL Learners

ERIC Educational Resources Information Center

Armagan, Kiymet Selin; Genc, Zubeyde Sinem

2017-01-01

Reading process has always been one of the most significant and debatable topics in the area of learning and teaching languages. Reading process in mother tongue (L1) and in a foreign language (L2), the association of these processes, variables affecting reading and the qualities of good and poor readers in L1 and L2 have been investigated…

Evidence of opposing fitness effects of parental heterozygosity and relatedness in a critically endangered marine turtle?

PubMed

Phillips, K P; Jorgensen, T H; Jolliffe, K G; Richardson, D S

2017-11-01

How individual genetic variability relates to fitness is important in understanding evolution and the processes affecting populations of conservation concern. Heterozygosity-fitness correlations (HFCs) have been widely used to study this link in wild populations, where key parameters that affect both variability and fitness, such as inbreeding, can be difficult to measure. We used estimates of parental heterozygosity and genetic similarity ('relatedness') derived from 32 microsatellite markers to explore the relationship between genetic variability and fitness in a population of the critically endangered hawksbill turtle, Eretmochelys imbricata. We found no effect of maternal MLH (multilocus heterozygosity) on clutch size or egg success rate, and no single-locus effects. However, we found effects of paternal MLH and parental relatedness on egg success rate that interacted in a way that may result in both positive and negative effects of genetic variability. Multicollinearity in these tests was within safe limits, and null simulations suggested that the effect was not an artefact of using paternal genotypes reconstructed from large samples of offspring. Our results could imply a tension between inbreeding and outbreeding depression in this system, which is biologically feasible in turtles: female-biased natal philopatry may elevate inbreeding risk and local adaptation, and both processes may be disrupted by male-biased dispersal. Although this conclusion should be treated with caution due to a lack of significant identity disequilibrium, our study shows the importance of considering both positive and negative effects when assessing how variation in genetic variability affects fitness in wild systems. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

Optimization of porthole die geometrical variables by Taguchi method

NASA Astrophysics Data System (ADS)

Gagliardi, F.; Ciancio, C.; Ambrogio, G.; Filice, L.

2017-10-01

Porthole die extrusion is commonly used to manufacture hollow profiles made of lightweight alloys for numerous industrial applications. The reliability of extruded parts is affected strongly by the quality of the longitudinal and transversal seam welds. According to that, the die geometry must be designed correctly and the process parameters must be selected properly to achieve the desired product quality. In this study, numerical 3D simulations have been created and run to investigate the role of various geometrical variables on punch load and maximum pressure inside the welding chamber. These are important outputs to take into account affecting, respectively, the necessary capacity of the extrusion press and the quality of the welding lines. The Taguchi technique has been used to reduce the number of the required numerical simulations necessary for considering the influence of twelve different geometric variables. Moreover, the Analysis of variance (ANOVA) has been implemented to individually analyze the effect of each input parameter on the two responses. Then, the methodology has been utilized to determine the optimal process configuration individually optimizing the two investigated process outputs. Finally, the responses of the optimized parameters have been verified through finite element simulations approximating the predicted value closely. This study shows the feasibility of the Taguchi technique for predicting performance, optimization and therefore for improving the design of a porthole extrusion process.

Using Bayesian Nonparametric Hidden Semi-Markov Models to Disentangle Affect Processes during Marital Interaction

PubMed Central

Griffin, William A.; Li, Xun

2016-01-01

Sequential affect dynamics generated during the interaction of intimate dyads, such as married couples, are associated with a cascade of effects—some good and some bad—on each partner, close family members, and other social contacts. Although the effects are well documented, the probabilistic structures associated with micro-social processes connected to the varied outcomes remain enigmatic. Using extant data we developed a method of classifying and subsequently generating couple dynamics using a Hierarchical Dirichlet Process Hidden semi-Markov Model (HDP-HSMM). Our findings indicate that several key aspects of existing models of marital interaction are inadequate: affect state emissions and their durations, along with the expected variability differences between distressed and nondistressed couples are present but highly nuanced; and most surprisingly, heterogeneity among highly satisfied couples necessitate that they be divided into subgroups. We review how this unsupervised learning technique generates plausible dyadic sequences that are sensitive to relationship quality and provide a natural mechanism for computational models of behavioral and affective micro-social processes. PMID:27187319

[Heart rate variability of subjects when the instruction reading and their interrelations with the effectiveness of the follow-visual-motor activities].

PubMed

Murtazina, E P

2015-01-01

Investigation of the processes of studying human instructions relevant follow-up in terms of systemic mechanisms of learning and memory processes, and moreover affects such a fundamental issue as psychophysiology focused attention, understanding the meaning of the information provided and the formation of social motivation in human activities. Analysis of heart rate variability in reading the instructions compared to the initial state of operational rest showed that this stage of the activity causes pronounced emotional stress, which is manifested in increased heart rate, decrease in variability and pronounced changes in the spectral characteristics of heart rate. Besides, it was revealed that heart rate variability in a state of operational rest before testing, and in the process of reading instructions positively correlated with the duration of the instruction reading and inversely correlated with effectiveness and the level of resistance of the subjects to the error after error when follow-up activities. Showing pronounced gender differences in the relationships between changes in the variability of heart rate when reading the instructions and the subsequent execution indicators of visual-motor test.

The role of physician characteristics in clinical trial acceptance: testing pathways of influence.

PubMed

Curbow, Barbara; Fogarty, Linda A; McDonnell, Karen A; Chill, Julia; Scott, Lisa Benz

2006-03-01

Eight videotaped vignettes were developed that assessed the effects of three physician-related experimental variables (in a 2 x 2 x 2 factorial design) on clinical trial (CT) knowledge, video knowledge, information processing, CT beliefs, affective evaluations (attitudes), and CT acceptance. It was hypothesized that the physician variables (community versus academic-based affiliation, enthusiastic versus neutral presentation of the trial, and new versus previous relationship with the patient) would serve as communication cues that would interrupt message processing, leading to lower knowledge gain but more positive beliefs, attitudes, and CT acceptance. A total of 262 women (161 survivors and 101 controls) participated in the study. The manipulated variables primarily influenced the intermediary variables of post-test CT beliefs and satisfaction with information rather than knowledge or information processing. Multiple regression results indicated that CT acceptance was associated with positive post-CT beliefs, a lower level of information processing, satisfaction with information, and control status. Based on these results, CT acceptance does not appear to be based on a rational decision-making model; this has implications for both the ethics of informed consent and research conceptual models.

Co-extrusion of food grains-banana pulp for nutritious snacks: optimization of process variables.

PubMed

Mridula, D; Sethi, Swati; Tushir, Surya; Bhadwal, Sheetal; Gupta, R K; Nanda, S K

2017-08-01

Present study was undertaken to optimize the process conditions for development of food grains (maize, defatted soy flour, sesame seed)-banana based nutritious expanded snacks using extrusion processing. Experiments were designed using Box-Behnken design with banana pulp (8-24 g), screw speed (300-350 rpm) and feed moisture (14-16% w.b.). Seven responses viz. expansion ratio (ER), bulk density (BD), water absorption index (WAI), protein, minerals, iron and sensory acceptability were considered for optimizing independent parameters. ER, BD, WAI, protein content, total minerals, iron content, and overall acceptability ranged 2.69-3.36, 153.43-238.83 kg/m 3 , 4.56-4.88 g/g, 15.19-15.52%, 2.06-2.27%, 4.39-4.67 mg/100 g (w.b.) and 6.76-7.36, respectively. ER was significantly affected by all three process variables while BD was influenced by banana pulp and screw speed only. Studied process variables did not affected colour quality except 'a' value with banana pulp and screw speed. Banana pulp had positive correlation with water solubility index, total minerals and iron content and negative with WAI, protein and overall acceptability. Based upon multiple response analysis, optimized conditions were 8 g banana pulp, 350 rpm screw speed and 14% feed moisture indicating the protein, calorie, iron content and overall sensory acceptability in sample as 15.46%, 401 kcal/100 g, 4.48 mg/100 g and 7.6 respectively.

Production of biodiesel from Jatropha curcas L. oil catalyzed by SO₄²⁻/ZrO₂ catalyst: effect of interaction between process variables.

PubMed

Yee, Kian Fei; Lee, Keat Teong; Ceccato, Riccardo; Abdullah, Ahmad Zuhairi

2011-03-01

This study reports the conversion of Jatrophacurcas L. oil to biodiesel catalyzed by sulfated zirconia loaded on alumina catalyst using response surface methodology (RSM), specifically to study the effect of interaction between process variables on the yield of biodiesel. The transesterification process variables studied were reaction temperature, reaction duration, molar ratio of methanol to oil and catalyst loading. Results from this study revealed that individual as well as interaction between variables significantly affect the yield of biodiesel. With this information, it was found that 4h of reaction at 150°C, methanol to oil molar ratio of 9.88 mol/mol and 7.61 wt.% for catalyst loading gave an optimum biodiesel yield of 90.32 wt.%. The fuel properties of Jatropha biodiesel were characterized and it indeed met the specification for biodiesel according to ASTM D6751. Copyright © 2010 Elsevier Ltd. All rights reserved.

The contribution of local and transport processes to phytoplankton biomass variability over different timescales in the Upper James River, Virginia

NASA Astrophysics Data System (ADS)

Qin, Qubin; Shen, Jian

2017-09-01

Although both local processes (photosynthesis, respiration, grazing, and settling), and transport processes (advective transport and diffusive transport) significantly affect local phytoplankton dynamics, it is difficult to separate their contributions and to investigate the relative importance of each process to the local variability of phytoplankton biomass over different timescales. A method of using the transport rate is introduced to quantify the contribution of transport processes. By combining the time-varying transport rate and high-frequency observed chlorophyll a data, we can explicitly examine the impact of local and transport processes on phytoplankton biomass over a range of timescales from hourly to annually. For the Upper James River, results show that the relative importance of local and transport processes differs on different timescales. Local processes dominate phytoplankton variability on daily to weekly timescales, whereas the contribution of transport processes increases on seasonal to annual timescales and reaches equilibrium with local processes. With the use of the transport rate and high-frequency chlorophyll a data, a method similar to the open water oxygen method for metabolism is also presented to estimate phytoplankton primary production.

Raw material variability of an active pharmaceutical ingredient and its relevance for processability in secondary continuous pharmaceutical manufacturing.

PubMed

Stauffer, F; Vanhoorne, V; Pilcer, G; Chavez, P-F; Rome, S; Schubert, M A; Aerts, L; De Beer, T

2018-06-01

Active Pharmaceutical Ingredients (API) raw material variability is not always thoroughly considered during pharmaceutical process development, mainly due to low quantities of drug substance available. However, synthesis, crystallization routes and production sites evolve during product development and product life cycle leading to changes in physical material attributes which can potentially affect their processability. Recent literature highlights the need for a global approach to understand the link between material synthesis, material variability, process and product quality. The study described in this article aims at explaining the raw material variability of an API using extensive material characterization on a restricted number of representative batches using multivariate data analysis. It is part of a larger investigation trying to link the API drug substance manufacturing process, the resulting physical API raw material attributes and the drug product continuous manufacturing process. Eight API batches produced using different synthetic routes, crystallization, drying, delumping processes and processing equipment were characterized, extensively. Seventeen properties from seven characterization techniques were retained for further analysis using Principal Component Analysis (PCA). Three principal components (PCs) were sufficient to explain 92.9% of the API raw material variability. The first PC was related to crystal length, agglomerate size and fraction, flowability and electrostatic charging. The second PC was driven by the span of the particle size distribution and the agglomerates strength. The third PC was related to surface energy. Additionally, the PCA allowed to summarize the API batch-to-batch variability in only three PCs which can be used in future drug product development studies to quantitatively evaluate the impact of the API raw material variability upon the drug product process. The approach described in this article could be applied to any other compound which is prone to batch-to-batch variability. Copyright © 2018 Elsevier B.V. All rights reserved.

Surface complexation modeling

USDA-ARS?s Scientific Manuscript database

Adsorption-desorption reactions are important processes that affect the transport of contaminants in the environment. Surface complexation models are chemical models that can account for the effects of variable chemical conditions, such as pH, on adsorption reactions. These models define specific ...

Exposure Science and Its Applications for Effective Environmental Management

EPA Science Inventory

Exposure is the link between environmental pollution and human/ecosystem health. Exposure science entails understanding the scientific processes that affect source emissions, transport and fate, spatio-temporal variability in the ambient concentrations, levels of contaminants tha...

Effect of initial bulk density on high-solids anaerobic digestion of MSW: General mechanism.

PubMed

Caicedo, Luis M; Wang, Hongtao; Lu, Wenjing; De Clercq, Djavan; Liu, Yanjun; Xu, Sai; Ni, Zhe

2017-06-01

Initial bulk density (IBD) is an important variable in anaerobic digestion since it defines and optimizes the treatment capacity of a system. This study reveals the mechanism on how IBD might affect anaerobic digestion of waste. Four different IBD values: D 1 (500-700kgm -3 ), D 2 (900-1000kgm -3 ), D 3 (1100-1200kgm -3 ) and D 4 (1200-1400kgm -3 ) were set and tested over a period of 90days in simulated landfill reactors. The main variables affected by the IBD are the methane generation, saturation degree, extraction of organic matter, and the total population of methanogens. The study identified that IBD >1000kgm -3 may have significant effect on methane generation, either prolonging the lag time or completely inhibiting the process. This study provides a new understanding of the anaerobic digestion process in saturated high-solids systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

Interaction between DRD2 variation and sound environment on mood and emotion-related brain activity.

PubMed

Quarto, T; Fasano, M C; Taurisano, P; Fazio, L; Antonucci, L A; Gelao, B; Romano, R; Mancini, M; Porcelli, A; Masellis, R; Pallesen, K J; Bertolino, A; Blasi, G; Brattico, E

2017-01-26

Sounds, like music and noise, are capable of reliably affecting individuals' mood and emotions. However, these effects are highly variable across individuals. A putative source of variability is genetic background. Here we explored the interaction between a functional polymorphism of the dopamine D2 receptor gene (DRD2 rs1076560, G>T, previously associated with the relative expression of D2S/L isoforms) and sound environment on mood and emotion-related brain activity. Thirty-eight healthy subjects were genotyped for DRD2 rs1076560 (G/G=26; G/T=12) and underwent functional magnetic resonance imaging (fMRI) during performance of an implicit emotion-processing task while listening to music or noise. Individual variation in mood induction was assessed before and after the task. Results showed mood improvement after music exposure in DRD2GG subjects and mood deterioration after noise exposure in GT subjects. Moreover, the music, as opposed to noise environment, decreased the striatal activity of GT subjects as well as the prefrontal activity of GG subjects while processing emotional faces. These findings suggest that genetic variability of dopamine receptors affects sound environment modulations of mood and emotion processing. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Measuring myokines with cardiovascular functions: pre-analytical variables affecting the analytical output.

PubMed

Lombardi, Giovanni; Sansoni, Veronica; Banfi, Giuseppe

2017-08-01

In the last few years, a growing number of molecules have been associated to an endocrine function of the skeletal muscle. Circulating myokine levels, in turn, have been associated with several pathophysiological conditions including the cardiovascular ones. However, data from different studies are often not completely comparable or even discordant. This would be due, at least in part, to the whole set of situations related to the preparation of the patient prior to blood sampling, blood sampling procedure, processing and/or store. This entire process constitutes the pre-analytical phase. The importance of the pre-analytical phase is often not considered. However, in routine diagnostics, the 70% of the errors are in this phase. Moreover, errors during the pre-analytical phase are carried over in the analytical phase and affects the final output. In research, for example, when samples are collected over a long time and by different laboratories, a standardized procedure for sample collecting and the correct procedure for sample storage are acknowledged. In this review, we discuss the pre-analytical variables potentially affecting the measurement of myokines with cardiovascular functions.

Synthesis and review: African environmental processes and water-cycle dynamics

NASA Astrophysics Data System (ADS)

Ichoku, Charles; Adegoke, Jimmy

2016-12-01

Africa’s vast landmass harbors a variety of physical processes that affect the environment and the water cycle. This focus issue on ‘African Environmental Processes and Water-Cycle Dynamics’ contains eight articles that address these phenomena from different but complementary perspectives. Fires used for agricultural and related purposes play a major role in land-cover change, surface albedo modifications, and smoke emission; all of which affect the environment and the water cycle in different ways. However, emissions of aerosols and trace gases are not restricted to fires, but also emanate from other natural and human activities. The African water cycle undergoes significant perturbations that are attributable to several factors, including the aforesaid environmental processes. These changes in the water cycle have produced severe drought and flooding events in recent decades that affect societal wellbeing across sub-Saharan Africa. The combined effects of the environmental processes and water-cycle dynamics affect and are affected by climate variability and can be propagated beyond the continent. Future studies should utilize the wealth of observations and modeling tools that are constantly improving to clearly elucidate the interrelationships between all of these phenomena for the benefit of society.

Synthesis and review: African environmental processes and water-cycle dynamics.

PubMed

Ichoku, Charles; Adegoke, Jimmy

2016-12-01

Africa's vast landmass harbors a variety of physical processes that affect the environment and the water cycle. This focus issue on 'African Environmental Processes and Water-Cycle Dynamics' contains eight articles that address these phenomena from different but complementary perspectives. Fires used for agricultural and related purposes play a major role in land-cover change, surface albedo modifications, and smoke emission; all of which affect the environment and the water cycle in different ways. However, emissions of aerosols and trace gases are not restricted to fires, but also emanate from other natural and human activities. The African water cycle undergoes significant perturbations that are attributable to several factors, including the aforesaid environmental processes. These changes in the water cycle have produced severe drought and flooding events in recent decades that affect societal wellbeing across sub-Saharan Africa. The combined effects of the environmental processes and water-cycle dynamics affect and are affected by climate variability and can be propagated beyond the continent. Future studies should utilize the wealth of observations and modeling tools that are constantly improving to clearly elucidate the interrelationships between all of these phenomena for the benefit of society.

Synthesis and review: African environmental processes and water-cycle dynamics

PubMed Central

Ichoku, Charles; Adegoke, Jimmy

2018-01-01

Africa’s vast landmass harbors a variety of physical processes that affect the environment and the water cycle. This focus issue on ‘African Environmental Processes and Water-Cycle Dynamics’ contains eight articles that address these phenomena from different but complementary perspectives. Fires used for agricultural and related purposes play a major role in land-cover change, surface albedo modifications, and smoke emission; all of which affect the environment and the water cycle in different ways. However, emissions of aerosols and trace gases are not restricted to fires, but also emanate from other natural and human activities. The African water cycle undergoes significant perturbations that are attributable to several factors, including the aforesaid environmental processes. These changes in the water cycle have produced severe drought and flooding events in recent decades that affect societal wellbeing across sub-Saharan Africa. The combined effects of the environmental processes and water-cycle dynamics affect and are affected by climate variability and can be propagated beyond the continent. Future studies should utilize the wealth of observations and modeling tools that are constantly improving to clearly elucidate the interrelationships between all of these phenomena for the benefit of society. PMID:29682001

Multi objective optimization model for minimizing production cost and environmental impact in CNC turning process

NASA Astrophysics Data System (ADS)

Widhiarso, Wahyu; Rosyidi, Cucuk Nur

2018-02-01

Minimizing production cost in a manufacturing company will increase the profit of the company. The cutting parameters will affect total processing time which then will affect the production cost of machining process. Besides affecting the production cost and processing time, the cutting parameters will also affect the environment. An optimization model is needed to determine the optimum cutting parameters. In this paper, we develop an optimization model to minimize the production cost and the environmental impact in CNC turning process. The model is used a multi objective optimization. Cutting speed and feed rate are served as the decision variables. Constraints considered are cutting speed, feed rate, cutting force, output power, and surface roughness. The environmental impact is converted from the environmental burden by using eco-indicator 99. Numerical example is given to show the implementation of the model and solved using OptQuest of Oracle Crystal Ball software. The results of optimization indicate that the model can be used to optimize the cutting parameters to minimize the production cost and the environmental impact.

Emotion dysregulation in alexithymia: Startle reactivity to fearful affective imagery and its relation to heart rate variability.

PubMed

Panayiotou, Georgia; Constantinou, Elena

2017-09-01

Alexithymia is associated with deficiencies in recognizing and expressing emotions and impaired emotion regulation, though few studies have verified the latter assertion using objective measures. This study examined startle reflex modulation by fearful imagery and its associations with heart rate variability in alexithymia. Fifty-four adults (27 alexithymic) imagined previously normed fear scripts. Startle responses were assessed during baseline, first exposure, and reexposure. During first exposure, participants, in separate trials, engaged in either shallow or deep emotion processing, giving emphasis on descriptive or affective aspects of imagery, respectively. Resting heart rate variability was assessed during 2 min of rest prior to the experiment, with high alexithymic participants demonstrating significantly higher LF/HF (low frequency/high frequency) ratio than controls. Deep processing was associated with nonsignificantly larger and faster startle responses at first exposure for alexithymic participants. Lower LF/HF ratio, reflecting higher parasympathetic cardiac activity, predicted greater startle amplitude habituation for alexithymia but lower habituation for controls. Results suggest that, when exposed to prolonged threat, alexithymics may adjust poorly, showing a smaller initial defensive response but slower habituation. This pattern seems related to their low emotion regulation ability as indexed by heart rate variability. © 2017 Society for Psychophysiological Research.

Exploring the nature of facial affect processing deficits in schizophrenia.

PubMed

van 't Wout, Mascha; Aleman, André; Kessels, Roy P C; Cahn, Wiepke; de Haan, Edward H F; Kahn, René S

2007-04-15

Schizophrenia has been associated with deficits in facial affect processing, especially negative emotions. However, the exact nature of the deficit remains unclear. The aim of the present study was to investigate whether schizophrenia patients have problems in automatic allocation of attention as well as in controlled evaluation of facial affect. Thirty-seven patients with schizophrenia were compared with 41 control subjects on incidental facial affect processing (gender decision of faces with a fearful, angry, happy, disgusted, and neutral expression) and degraded facial affect labeling (labeling of fearful, angry, happy, and neutral faces). The groups were matched on estimates of verbal and performance intelligence (National Adult Reading Test; Raven's Matrices), general face recognition ability (Benton Face Recognition), and other demographic variables. The results showed that patients with schizophrenia as well as control subjects demonstrate the normal threat-related interference during incidental facial affect processing. Conversely, on controlled evaluation patients were specifically worse in the labeling of fearful faces. In particular, patients with high levels of negative symptoms may be characterized by deficits in labeling fear. We suggest that patients with schizophrenia show no evidence of deficits in the automatic allocation of attention resources to fearful (threat-indicating) faces, but have a deficit in the controlled processing of facial emotions that may be specific for fearful faces.

Negative affect and smoking motives sequentially mediate the effect of panic attacks on tobacco-relevant processes

PubMed Central

Farris, Samantha G.; Zvolensky, Michael J.; Blalock, Janice A.; Schmidt, Norman B.

2018-01-01

Introduction Empirical work has documented a robust and consistent relation between panic attacks and smoking behavior. Theoretical models posit smokers with panic attacks may rely on smoking to help them manage chronically elevated negative affect due to uncomfortable bodily states, which may explain higher levels of nicotine dependence and quit problems. Methods The current study examined the effects of panic attack history on nicotine dependence, perceived barriers for quitting, smoking inflexibility when emotionally distressed, and expired carbon monoxide among 461 treatment-seeking smokers. A multiple mediator path model was evaluated to examine the indirect effects of negative affect and negative affect reduction motives as mediators of the panic attack-smoking relations. Results Panic attack history was indirectly related to greater levels of nicotine dependence (b=0.039, CI95%=0.008, 0.097), perceived barriers to smoking cessation (b=0.195, CI95%=0.043, 0.479), smoking inflexibility/avoidance when emotionally distressed (b=0.188, CI95%=0.041, 0.445), and higher levels of expired carbon monoxide (b=0.071, CI95%=0.010, 0.230) through the sequential effects of negative affect and negative affect smoking motives. Conclusions The present results provide empirical support for the sequential mediating role of negative affect and smoking motives for negative affect reduction in the relation between panic attacks and a variety of smoking variables in treatment-seeking smokers. These mediating variables are likely important processes to address in smoking cessation treatment, especially in panic-vulnerable smokers. PMID:24720260

Negative affect and smoking motives sequentially mediate the effect of panic attacks on tobacco-relevant processes.

PubMed

Farris, Samantha G; Zvolensky, Michael J; Blalock, Janice A; Schmidt, Norman B

2014-05-01

Empirical work has documented a robust and consistent relation between panic attacks and smoking behavior. Theoretical models posit smokers with panic attacks may rely on smoking to help them manage chronically elevated negative affect due to uncomfortable bodily states, which may explain higher levels of nicotine dependence and quit problems. The current study examined the effects of panic attack history on nicotine dependence, perceived barriers for quitting, smoking inflexibility when emotionally distressed, and expired carbon monoxide among 461 treatment-seeking smokers. A multiple mediator path model was evaluated to examine the indirect effects of negative affect and negative affect reduction motives as mediators of the panic attack-smoking relations. Panic attack history was indirectly related to greater levels of nicotine dependence (b = 0.039, CI95% = 0.008, 0.097), perceived barriers to smoking cessation (b = 0.195, CI95% = 0.043, 0.479), smoking inflexibility/avoidance when emotionally distressed (b = 0.188, CI95% = 0.041, 0.445), and higher levels of expired carbon monoxide (b = 0.071, CI95% = 0.010, 0.230) through the sequential effects of negative affect and negative affect smoking motives. The present results provide empirical support for the sequential mediating role of negative affect and smoking motives for negative affect reduction in the relation between panic attacks and a variety of smoking variables in treatment-seeking smokers. These mediating variables are likely important processes to address in smoking cessation treatment, especially in panic-vulnerable smokers.

When is affect variability bad for health? The association between affect variability and immune response to the influenza vaccination.

PubMed

Jenkins, Brooke N; Hunter, John F; Cross, Marie P; Acevedo, Amanda M; Pressman, Sarah D

2018-01-01

This study addresses methodological and theoretical questions about the association between affect and physical health. Specifically, we examine the role of affect variability and its interaction with mean levels of affect to predict antibody (Ab) levels in response to an influenza vaccination. Participants (N=83) received the vaccination and completed daily diary measures of affect four times a day for 13days. At one and four months post-vaccination, blood was collected from the participants to assess Ab levels. Findings indicate that affect variability and its interaction with mean levels of affect predict an individual's immune response. Those high in mean positive affect (PA) who had more PA variability were more likely to have a lower Ab response in comparison to those who had high mean PA and less PA variability. Although it did not interact with mean negative affect (NA), NA variability on its own was associated with Ab response, whereby those with less NA variability mounted a more robust immune response. Affect variability is related to immune response to an influenza vaccination and, in some cases, interacts with mean levels of affect. These oscillations in affective experiences are critical to consider in order to unpack the intricacies of how affect influences health. These findings suggest that future researchers should consider the important role of affect variability on physical health-relevant outcomes as well as examine the moderating effect of mean affect levels. Copyright © 2017 Elsevier Inc. All rights reserved.

Individual movement behavior, matrix heterogeneity, and the dynamics of spatially structured populations.

PubMed

Revilla, Eloy; Wiegand, Thorsten

2008-12-09

The dynamics of spatially structured populations is characterized by within- and between-patch processes. The available theory describes the latter with simple distance-dependent functions that depend on landscape properties such as interpatch distance or patch size. Despite its potential role, we lack a good mechanistic understanding of how the movement of individuals between patches affects the dynamics of these populations. We used the theoretical framework provided by movement ecology to make a direct representation of the processes determining how individuals connect local populations in a spatially structured population of Iberian lynx. Interpatch processes depended on the heterogeneity of the matrix where patches are embedded and the parameters defining individual movement behavior. They were also very sensitive to the dynamic demographic variables limiting the time moving, the within-patch dynamics of available settlement sites (both spatiotemporally heterogeneous) and the response of individuals to the perceived risk while moving. These context-dependent dynamic factors are an inherent part of the movement process, producing connectivities and dispersal kernels whose variability is affected by other demographic processes. Mechanistic representations of interpatch movements, such as the one provided by the movement-ecology framework, permit the dynamic interaction of birth-death processes and individual movement behavior, thus improving our understanding of stochastic spatially structured populations.

Proximal soil sensing: global perspective

USDA-ARS?s Scientific Manuscript database

As a result of a number of naturally occurring processes and cultural practices, the characteristics of soils demonstrate substantial spatial heterogeneity that affects current land use. From infrastructure development to agriculture, spatial variability in soils must be taken into account in order ...

A plant’s perspective of extremes: Terrestrial plant responses to changing climatic variability

PubMed Central

Reyer, C.; Leuzinger, S.; Rammig, A.; Wolf, A.; Bartholomeus, R. P.; Bonfante, A.; de Lorenzi, F.; Dury, M.; Gloning, P.; Abou Jaoudé, R.; Klein, T.; Kuster, T. M.; Martins, M.; Niedrist, G.; Riccardi, M.; Wohlfahrt, G.; de Angelis, P.; de Dato, G.; François, L.; Menzel, A.; Pereira, M.

2013-01-01

We review observational, experimental and model results on how plants respond to extreme climatic conditions induced by changing climatic variability. Distinguishing between impacts of changing mean climatic conditions and changing climatic variability on terrestrial ecosystems is generally underrated in current studies. The goals of our review are thus (1) to identify plant processes that are vulnerable to changes in the variability of climatic variables rather than to changes in their mean, and (2) to depict/evaluate available study designs to quantify responses of plants to changing climatic variability. We find that phenology is largely affected by changing mean climate but also that impacts of climatic variability are much less studied but potentially damaging. We note that plant water relations seem to be very vulnerable to extremes driven by changes in temperature and precipitation and that heatwaves and flooding have stronger impacts on physiological processes than changing mean climate. Moreover, interacting phenological and physiological processes are likely to further complicate plant responses to changing climatic variability. Phenological and physiological processes and their interactions culminate in even more sophisticated responses to changing mean climate and climatic variability at the species and community level. Generally, observational studies are well suited to study plant responses to changing mean climate, but less suitable to gain a mechanistic understanding of plant responses to climatic variability. Experiments seem best suited to simulate extreme events. In models, temporal resolution and model structure are crucial to capture plant responses to changing climatic variability. We highlight that a combination of experimental, observational and /or modeling studies have the potential to overcome important caveats of the respective individual approaches. PMID:23504722

Understanding Hydrological Processes in Variable Source Areas in the Glaciated Northeastern US Watersheds under Variable Climate Conditions

NASA Astrophysics Data System (ADS)

Steenhuis, T. S.; Azzaino, Z.; Hoang, L.; Pacenka, S.; Worqlul, A. W.; Mukundan, R.; Stoof, C.; Owens, E. M.; Richards, B. K.

2017-12-01

The New York City source watersheds in the Catskill Mountains' humid, temperate climate has long-term hydrological and water quality monitoring data It is one of the few catchments where implementation of source and landscape management practices has led to decreased phosphorus concentration in the receiving surface waters. One of the reasons is that landscape measures correctly targeted the saturated variable source runoff areas (VSA) in the valley bottoms as the location where most of the runoff and other nonpoint pollutants originated. Measures targeting these areas were instrumental in lowering phosphorus concentration. Further improvements in water quality can be made based on a better understanding of the flow processes and water table fluctuations in the VSA. For that reason, we instrumented a self-contained upland variable source watershed with a landscape characteristic of a soil underlain by glacial till at shallow depth similar to the Catskill watersheds. In this presentation, we will discuss our experimental findings and present a mathematical model. Variable source areas have a small slope making gravity the driving force for the flow, greatly simplifying the simulation of the flow processes. The experimental data and the model simulations agreed for both outflow and water table fluctuations. We found that while the flows to the outlet were similar throughout the year, the discharge of the VSA varies greatly. This was due to transpiration by the plants which became active when soil temperatures were above 10oC. We found that shortly after the temperature increased above 10oC the baseflow stopped and only surface runoff occurred when rainstorms exceeded the storage capacity of the soil in at least a portion of the variable source area. Since plant growth in the variable source area was a major variable determining the base flow behavior, changes in temperature in the future - affecting the duration of the growing season - will affect baseflow and related transport of nutrient and other chemicals many times more than small temperature related increases in potential evaporation rate. This in turn will directly change the water availability and pollutant transport in the many surface source watersheds with variable source area hydrology.

Mastoid vibration affects dynamic postural control during gait in healthy older adults

NASA Astrophysics Data System (ADS)

Chien, Jung Hung; Mukherjee, Mukul; Kent, Jenny; Stergiou, Nicholas

2017-01-01

Vestibular disorders are difficult to diagnose early due to the lack of a systematic assessment. Our previous work has developed a reliable experimental design and the result shows promising results that vestibular sensory input while walking could be affected through mastoid vibration (MV) and changes are in the direction of motion. In the present paper, we wanted to extend this work to older adults and investigate how manipulating sensory input through mastoid vibration (MV) could affect dynamic postural control during walking. Three levels of MV (none, unilateral, and bilateral) applied via vibrating elements placed on the mastoid processes were combined with the Locomotor Sensory Organization Test (LSOT) paradigm to challenge the visual and somatosensory systems. We hypothesized that the MV would affect sway variability during walking in older adults. Our results revealed that MV significantly not only increased the amount of sway variability but also decreased the temporal structure of sway variability only in anterior-posterior direction. Importantly, the bilateral MV stimulation generally produced larger effects than the unilateral. This is an important finding that confirmed our experimental design and the results produced could guide a more reliable screening of vestibular system deterioration.

On the relationship between personal experience, affect and risk perception: The case of climate change

PubMed Central

van der Linden, Sander

2014-01-01

Examining the conceptual relationship between personal experience, affect, and risk perception is crucial in improving our understanding of how emotional and cognitive process mechanisms shape public perceptions of climate change. This study is the first to investigate the interrelated nature of these variables by contrasting three prominent social-psychological theories. In the first model, affect is viewed as a fast and associative information processing heuristic that guides perceptions of risk. In the second model, affect is seen as flowing from cognitive appraisals (i.e., affect is thought of as a post-cognitive process). Lastly, a third, dual-process model is advanced that integrates aspects from both theoretical perspectives. Four structural equation models were tested on a national sample (N = 808) of British respondents. Results initially provide support for the “cognitive” model, where personal experience with extreme weather is best conceptualized as a predictor of climate change risk perception and, in turn, risk perception a predictor of affect. Yet, closer examination strongly indicates that at the same time, risk perception and affect reciprocally influence each other in a stable feedback system. It is therefore concluded that both theoretical claims are valid and that a dual-process perspective provides a superior fit to the data. Implications for theory and risk communication are discussed. © 2014 The Authors. European Journal of Social Psychology published by John Wiley & Sons, Ltd. PMID:25678723

Variability in, variability out: best practice recommendations to standardize pre-analytical variables in the detection of circulating and tissue microRNAs.

PubMed

Khan, Jenna; Lieberman, Joshua A; Lockwood, Christina M

2017-05-01

microRNAs (miRNAs) hold promise as biomarkers for a variety of disease processes and for determining cell differentiation. These short RNA species are robust, survive harsh treatment and storage conditions and may be extracted from blood and tissue. Pre-analytical variables are critical confounders in the analysis of miRNAs: we elucidate these and identify best practices for minimizing sample variation in blood and tissue specimens. Pre-analytical variables addressed include patient-intrinsic variation, time and temperature from sample collection to storage or processing, processing methods, contamination by cells and blood components, RNA extraction method, normalization, and storage time/conditions. For circulating miRNAs, hemolysis and blood cell contamination significantly affect profiles; samples should be processed within 2 h of collection; ethylene diamine tetraacetic acid (EDTA) is preferred while heparin should be avoided; samples should be "double spun" or filtered; room temperature or 4 °C storage for up to 24 h is preferred; miRNAs are stable for at least 1 year at -20 °C or -80 °C. For tissue-based analysis, warm ischemic time should be <1 h; cold ischemic time (4 °C) <24 h; common fixative used for all specimens; formalin fix up to 72 h prior to processing; enrich for cells of interest; validate candidate biomarkers with in situ visualization. Most importantly, all specimen types should have standard and common workflows with careful documentation of relevant pre-analytical variables.

A Study of Light Level Effect on the Accuracy of Image Processing-based Tomato Grading

NASA Astrophysics Data System (ADS)

Prijatna, D.; Muhaemin, M.; Wulandari, R. P.; Herwanto, T.; Saukat, M.; Sugandi, W. K.

2018-05-01

Image processing method has been used in non-destructive tests of agricultural products. Compared to manual method, image processing method may produce more objective and consistent results. Image capturing box installed in currently used tomato grading machine (TEP-4) is equipped with four fluorescence lamps to illuminate the processed tomatoes. Since the performance of any lamp will decrease if its service time has exceeded its lifetime, it is predicted that this will affect tomato classification. The objective of this study was to determine the minimum light levels which affect classification accuracy. This study was conducted by varying light level from minimum and maximum on tomatoes in image capturing boxes and then investigates its effects on image characteristics. Research results showed that light intensity affects two variables which are important for classification, for example, area and color of captured image. Image processing program was able to determine correctly the weight and classification of tomatoes when light level was 30 lx to 140 lx.

Multi-objective optimization model of CNC machining to minimize processing time and environmental impact

NASA Astrophysics Data System (ADS)

Hamada, Aulia; Rosyidi, Cucuk Nur; Jauhari, Wakhid Ahmad

2017-11-01

Minimizing processing time in a production system can increase the efficiency of a manufacturing company. Processing time are influenced by application of modern technology and machining parameter. Application of modern technology can be apply by use of CNC machining, one of the machining process can be done with a CNC machining is turning. However, the machining parameters not only affect the processing time but also affect the environmental impact. Hence, optimization model is needed to optimize the machining parameters to minimize the processing time and environmental impact. This research developed a multi-objective optimization to minimize the processing time and environmental impact in CNC turning process which will result in optimal decision variables of cutting speed and feed rate. Environmental impact is converted from environmental burden through the use of eco-indicator 99. The model were solved by using OptQuest optimization software from Oracle Crystal Ball.

Does climate variability influence the demography of wild primates? Evidence from long-term life-history data in seven species.

PubMed

Campos, Fernando A; Morris, William F; Alberts, Susan C; Altmann, Jeanne; Brockman, Diane K; Cords, Marina; Pusey, Anne; Stoinski, Tara S; Strier, Karen B; Fedigan, Linda M

2017-11-01

Earth's rapidly changing climate creates a growing need to understand how demographic processes in natural populations are affected by climate variability, particularly among organisms threatened by extinction. Long-term, large-scale, and cross-taxon studies of vital rate variation in relation to climate variability can be particularly valuable because they can reveal environmental drivers that affect multiple species over extensive regions. Few such data exist for animals with slow life histories, particularly in the tropics, where climate variation over large-scale space is asynchronous. As our closest relatives, nonhuman primates are especially valuable as a resource to understand the roles of climate variability and climate change in human evolutionary history. Here, we provide the first comprehensive investigation of vital rate variation in relation to climate variability among wild primates. We ask whether primates are sensitive to global changes that are universal (e.g., higher temperature, large-scale climate oscillations) or whether they are more sensitive to global change effects that are local (e.g., more rain in some places), which would complicate predictions of how primates in general will respond to climate change. To address these questions, we use a database of long-term life-history data for natural populations of seven primate species that have been studied for 29-52 years to investigate associations between vital rate variation, local climate variability, and global climate oscillations. Associations between vital rates and climate variability varied among species and depended on the time windows considered, highlighting the importance of temporal scale in detection of such effects. We found strong climate signals in the fertility rates of three species. However, survival, which has a greater impact on population growth, was little affected by climate variability. Thus, we found evidence for demographic buffering of life histories, but also evidence of mechanisms by which climate change could affect the fates of wild primates. © 2017 John Wiley & Sons Ltd.

Marked and variable inhibition by chemical fixation of cytochrome oxidase and succinate dehydrogenase in single motoneurons

NASA Technical Reports Server (NTRS)

Chalmers, G. R.; Edgerton, V. R.

1989-01-01

The effect of tissue fixation on succinate dehydrogenase and cytochrome oxidase activity in single motoneurons of the rat was demonstrated using a computer image processing system. Inhibition of enzyme activity by chemical fixation was variable, with some motoneurons being affected more than others. It was concluded that quantification of enzymatic activity in chemically fixed tissue provides an imprecise estimate of enzyme activities found in fresh-frozen tissues.

Thermal Management in Friction-Stir Welding of Precipitation-Hardening Aluminum Alloys

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

Upadhyay, Piyush; Reynolds, Anthony

2015-05-25

Process design and implementation in FSW is mostly dependent on empirical information gathered through experience. Basic science of friction stir welding and processing can only be complete when fundamental interrelationships between process control parameters and response variables and resulting weld microstructure and properties are established to a reasonable extent. It is known that primary process control parameters like tool rotation and translation rate and forge axis force have complicated and interactive relationships to the process response variables such as peak temperature, time at temperature etc. Of primary influence to the other process response parameters are temperature and its gradient atmore » the deformation and heat affected zones. Through review of pertinent works in the literature and some experimental results from boundary condition work performed in precipitation hardening aluminum alloys this paper will partially elucidate the nature and effects of temperature transients caused by variation of thermal boundaries in Friction Stir Welding.« less

Thermal Management in Friction-Stir Welding of Precipitation-Hardened Aluminum Alloys

NASA Astrophysics Data System (ADS)

Upadhyay, Piyush; Reynolds, Anthony P.

2015-05-01

Process design and implementation in friction-stir welding (FSW) is mostly dependent on empirical information. Basic science of FSW and processing can only be complete when fundamental interrelationships between the process control parameters and response variables and the resulting weld microstructure and properties are established to a reasonable extent. It is known that primary process control parameters such as tool rotation, translation rates, and forge axis force have complicated and interactive relationships to process-response variables such as peak temperature and time at temperature. Of primary influence on the other process-response parameters are temperature and its gradient in the deformation and heat-affected zones. Through a review of pertinent works in the literature and results from boundary condition experiments performed in precipitation-hardening aluminum alloys, this article partially elucidates the nature and effects of temperature transients caused by variation of thermal boundaries in FSW.

Effects of long-term voluntary exercise on learning and memory processes: dependency of the task and level of exercise.

PubMed

García-Capdevila, Sílvia; Portell-Cortés, Isabel; Torras-Garcia, Meritxell; Coll-Andreu, Margalida; Costa-Miserachs, David

2009-09-14

The effect of long-term voluntary exercise (running wheel) on anxiety-like behaviour (plus maze and open field) and learning and memory processes (object recognition and two-way active avoidance) was examined on Wistar rats. Because major individual differences in running wheel behaviour were observed, the data were analysed considering the exercising animals both as a whole and grouped according to the time spent in the running wheel (low, high, and very-high running). Although some variables related to anxiety-like behaviour seem to reflect an anxiogenic compatible effect, the view of the complete set of variables could be interpreted as an enhancement of defensive and risk assessment behaviours in exercised animals, without major differences depending on the exercise level. Effects on learning and memory processes were dependent on task and level of exercise. Two-way avoidance was not affected either in the acquisition or in the retention session, while the retention of object recognition task was affected. In this latter task, an enhancement in low running subjects and impairment in high and very-high running animals were observed.

Identification of formulation and manufacturing variables that influence in vitro dissolution and in vivo bioavailability of propranolol hydrochloride tablets.

PubMed

Eddington, N D; Ashraf, M; Augsburger, L L; Leslie, J L; Fossler, M J; Lesko, L J; Shah, V P; Rekhi, G S

1998-11-01

The purpose of this study was to evaluate the effect of formulation and processing changes on the dissolution and bioavailability of propranolol hydrochloride tablets. Directly compressed blends of 6 kg (20,000 units) were prepared by mixing in a 16-qt V blender and tablets were compressed on an instrumented Manesty D3B tablet press. A half-factorial (2(5-1), Resolution V) design was used to study the following variables: filler ratio (lactose/dicalcium phosphate), sodium starch glycolate level, magnesium stearate level, lubricant blend time, and compression force. The levels and ranges of the excipients and processing changes studied represented level 2 or greater changes as indicated by the Scale-up and Post Approval Changes (SUPAC-IR) Guidance. Changes in filler ratio, disintegrant level, and compression force were significant in affecting percent drug released (Q) in 5 min (Q5) and Q10. However, changes in magnesium stearate level and lubricant blend time did not influence Q5 and Q10. Hardness was found to be affected by changes in all of the variables studied. Some interaction effects between the variables studied were also found to be significant. To examine the impact of formulation and processing variables on in vivo absorption, three batches were selected for a bioavailability study based on their dissolution profiles. Thirteen subjects received four propranolol treatments (slow-, medium-, and fast-dissolving formulations and Inderal 80 mg) separated by 1 week washout according to a randomized crossover design. The formulations were found to be bioequivalent with respect to the log Cmax and log AUC0-infinity. The results of this study suggest that (i) bioavailability/bioequivalency studies may not be necessary for propranolol and perhaps other class 1 drugs after level 2 type changes, and (ii) in vitro dissolution tests may be used to show bioequivalence of propranolol formulations with processing or formulation changes within the specified level 2 ranges examined.

Motivation as an independent and a dependent variable in medical education: a review of the literature.

PubMed

Kusurkar, R A; Ten Cate, Th J; van Asperen, M; Croiset, G

2011-01-01

Motivation in learning behaviour and education is well-researched in general education, but less in medical education. To answer two research questions, 'How has the literature studied motivation as either an independent or dependent variable? How is motivation useful in predicting and understanding processes and outcomes in medical education?' in the light of the Self-determination Theory (SDT) of motivation. A literature search performed using the PubMed, PsycINFO and ERIC databases resulted in 460 articles. The inclusion criteria were empirical research, specific measurement of motivation and qualitative research studies which had well-designed methodology. Only studies related to medical students/school were included. Findings of 56 articles were included in the review. Motivation as an independent variable appears to affect learning and study behaviour, academic performance, choice of medicine and specialty within medicine and intention to continue medical study. Motivation as a dependent variable appears to be affected by age, gender, ethnicity, socioeconomic status, personality, year of medical curriculum and teacher and peer support, all of which cannot be manipulated by medical educators. Motivation is also affected by factors that can be influenced, among which are, autonomy, competence and relatedness, which have been described as the basic psychological needs important for intrinsic motivation according to SDT. Motivation is an independent variable in medical education influencing important outcomes and is also a dependent variable influenced by autonomy, competence and relatedness. This review finds some evidence in support of the validity of SDT in medical education.

Analysis of multi-year near-surface ozone observations at the WMO/GAW "Concordia" station (75°06‧S, 123°20‧E, 3280 m a.s.l. - Antarctica)

NASA Astrophysics Data System (ADS)

Cristofanelli, Paolo; Putero, Davide; Bonasoni, Paolo; Busetto, Maurizio; Calzolari, Francescopiero; Camporeale, Giuseppe; Grigioni, Paolo; Lupi, Angelo; Petkov, Boyan; Traversi, Rita; Udisti, Roberto; Vitale, Vito

2018-03-01

This work focuses on the near-surface O3 variability over the eastern Antarctic Plateau. In particular, eight years (2006-2013) of continuous observations at the WMO/GAW contributing station "Concordia" (Dome C-DMC: 75°06‧S, 123°20‧E, 3280 m) are presented, in the framework of the Italian Antarctic Research Programme (PNRA). First, the characterization of seasonal and diurnal O3 variability at DMC is provided. Then, for the period of highest data coverage (2008-2013), we investigated the role of specific atmospheric processes in affecting near-surface summer O3 variability, when O3 enhancement events (OEEs) are systematically observed at DMC (average monthly frequency peaking up to 60% in December). As deduced by a statistical selection methodology, these OEEs are affected by a significant interannual variability, both in their average O3 values and in their frequency. To explain part of this variability, we analyzed OEEs as a function of specific atmospheric variables and processes: (i) total column of O3 (TCO) and UV-A irradiance, (ii) long-range transport of air masses over the Antarctic Plateau (by Lagrangian back-trajectory analysis - LAGRANTO), (iii) occurrence of "deep" stratospheric intrusion events (by using the Lagrangian tool STLEFLUX). The overall near-surface O3 variability at DMC is controlled by a day-to-day pattern, which strongly points towards a dominating influence of processes occurring at "synoptic" scales rather than "local" processes. Even if previous studies suggested an inverse relationship between OEEs and TCO, we found a slight tendency for the annual frequency of OEEs to be higher when TCO values are higher over DMC. The annual occurrence of OEEs at DMC seems related to the total time spent by air masses over the Antarctic plateau before their arrival to DMC, suggesting the accumulation of photochemically-produced O3 during the transport, rather than a more efficient local production. Moreover, the identification of recent (i.e., 4-day old) stratospheric intrusion events by STEFLUX suggested only a minor influence (up to 3% of the period, in November) of "deep" events on the variability of near-surface summer O3 at DMC.

Confidence limits for contribution plots in multivariate statistical process control using bootstrap estimates.

PubMed

Babamoradi, Hamid; van den Berg, Frans; Rinnan, Åsmund

2016-02-18

In Multivariate Statistical Process Control, when a fault is expected or detected in the process, contribution plots are essential for operators and optimization engineers in identifying those process variables that were affected by or might be the cause of the fault. The traditional way of interpreting a contribution plot is to examine the largest contributing process variables as the most probable faulty ones. This might result in false readings purely due to the differences in natural variation, measurement uncertainties, etc. It is more reasonable to compare variable contributions for new process runs with historical results achieved under Normal Operating Conditions, where confidence limits for contribution plots estimated from training data are used to judge new production runs. Asymptotic methods cannot provide confidence limits for contribution plots, leaving re-sampling methods as the only option. We suggest bootstrap re-sampling to build confidence limits for all contribution plots in online PCA-based MSPC. The new strategy to estimate CLs is compared to the previously reported CLs for contribution plots. An industrial batch process dataset was used to illustrate the concepts. Copyright © 2016 Elsevier B.V. All rights reserved.

Variability of the Labrador Sea Surface Eddy Kinetic Energy Observed by Altimeter From 1993 to 2012

NASA Astrophysics Data System (ADS)

Zhang, Weiwei; Yan, Xiao-Hai

2018-01-01

A merged along track altimeter data set is used to study the variability of eddy kinetic energy (EKE) in the Labrador Sea from 1993 to 2012. The EKE near the west Greenland current (WGC) has strong interannual variability without long-term trend from 1993 to 2012. The propagation direction of the Irminger Rings (IRs) originating from the WGC can be inferred from the EKE derived from altimeter, and the southward propagation of the IRs varies interannually. The central Labrador Sea EKE increases significantly from 1993 to 2012. The central Labrador Sea temperature difference between the end and the beginning of the winter convections is defined as restratification index to measure the restratification strengths. The relation between the central Labrador Sea EKE and the restratification index shows that the enhanced eddy activity originating from the west of the central Labrador Sea may cool the central Labrador Sea significantly. The interannual variability of the WGC EKE is likely to be driven by the large scale Subpolar Gyre (SPG) circulation variability and the North Atlantic Oscillation (NAO). The NAO also affects the central Labrador Sea EKE through its fingerprint in the local wind stress and surface heat flux. The NAO affects the WGC EKE by changing the SPG circulation strength, which will subsequently affect the WGC EKE through unknown physical processes.

Attachment change processes in the early years of marriage.

PubMed

Davila, J; Karney, B R; Bradbury, T N

1999-05-01

The authors examined 4 models of attachment change: a contextual model, a social-cognitive model, an individual-difference model, and a diathesis-stress model. Models were examined in a sample of newlyweds over the first 2 years of marriage, using growth curve analyses. Reciprocal processes, whereby attachment representations and interpersonal life circumstances affect one another over time, also were studied. On average, newlyweds became more secure over time. However, there was significant within-subject variability on attachment change that was predicted by intra- and interpersonal factors. Attachment representations changed in response to contextual, social-cognitive, and individual-difference factors. Reciprocal processes between attachment representations and marital variables emerged, suggesting that these factors influence one another in an ongoing way.

Modelling Pseudocalanus elongatus stage-structured population dynamics embedded in a water column ecosystem model for the northern North Sea

NASA Astrophysics Data System (ADS)

Moll, Andreas; Stegert, Christoph

2007-01-01

This paper outlines an approach to couple a structured zooplankton population model with state variables for eggs, nauplii, two copepodites stages and adults adapted to Pseudocalanus elongatus into the complex marine ecosystem model ECOHAM2 with 13 state variables resolving the carbon and nitrogen cycle. Different temperature and food scenarios derived from laboratory culture studies were examined to improve the process parameterisation for copepod stage dependent development processes. To study annual cycles under realistic weather and hydrographic conditions, the coupled ecosystem-zooplankton model is applied to a water column in the northern North Sea. The main ecosystem state variables were validated against observed monthly mean values. Then vertical profiles of selected state variables were compared to the physical forcing to study differences between zooplankton as one biomass state variable or partitioned into five population state variables. Simulated generation times are more affected by temperature than food conditions except during the spring phytoplankton bloom. Up to six generations within the annual cycle can be discerned in the simulation.

Valorisation of waste tyre by pyrolysis in a moving bed reactor.

PubMed

Aylón, E; Fernández-Colino, A; Murillo, R; Navarro, M V; García, T; Mastral, A M

2010-07-01

The aim of this work is to assess the behaviour of a moving bed reactor, based on a screw transporter design, in waste tyre pyrolysis under several experimental conditions. Waste tyre represents a significant problem in developed countries and it is necessary to develop new technology that could easily process big amounts of this potentially raw material. In this work, the influence of the main pyrolysis process variables (temperature, solid residence time, mass flow rate and inert gas flow) has been studied by a thorough analysis of product yields and properties. It has been found that regardless the process operational parameters, a total waste tyre devolatilisation is achieved, producing a pyrolytic carbon black with a volatile matter content under 5 wt.%. In addition, it has been proven that, in the range studied, the most influencing process variables are temperature and solid mass flow rate, mainly because both variables modify the gas residence time inside the reactor. In addition, it has been found that the modification of these variables affects to the chemical properties of the products. This fact is mainly associated to the different cracking reaction of the primary pyrolysis products. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

Valorisation of waste tyre by pyrolysis in a moving bed reactor

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

Aylon, E.; Fernandez-Colino, A.; Murillo, R., E-mail: ramonm@icb.csic.e

2010-07-15

The aim of this work is to assess the behaviour of a moving bed reactor, based on a screw transporter design, in waste tyre pyrolysis under several experimental conditions. Waste tyre represents a significant problem in developed countries and it is necessary to develop new technology that could easily process big amounts of this potentially raw material. In this work, the influence of the main pyrolysis process variables (temperature, solid residence time, mass flow rate and inert gas flow) has been studied by a thorough analysis of product yields and properties. It has been found that regardless the process operationalmore » parameters, a total waste tyre devolatilisation is achieved, producing a pyrolytic carbon black with a volatile matter content under 5 wt.%. In addition, it has been proven that, in the range studied, the most influencing process variables are temperature and solid mass flow rate, mainly because both variables modify the gas residence time inside the reactor. In addition, it has been found that the modification of these variables affects to the chemical properties of the products. This fact is mainly associated to the different cracking reaction of the primary pyrolysis products.« less

Which Are the Determinants of Online Students' Efficiency in Higher Education?

NASA Astrophysics Data System (ADS)

Castillo-Merino, David; Serradell-Lopez, Enric; González-González, Inés

International literature shows that the positive effect on students performance from the adoption of innovations in the technology of teaching and learning do not affect all teaching methods and learning styles equally, as it depends on university strategy and policy towards Information and Communication Technologies (ICT) adoption, students abilities, technology uses in the educational process by teachers and students, or the selection of a methodology that matches with digital uses. This paper provides empirical answers to these questions with data from online students at the Open University of Catalonia (UOC). An empirical model based on structural equations has been defined to explain complex relationships between variables. Our results show that motivation is the main variable affecting online students' performance. It appears as a latent variable influenced by students' perception of efficiency, a driver for indirect positive and significant effect on students' performance from students' ability in ICT uses.

Catch me if I fall! Enacted uncertainty avoidance and the social safety net as country-level moderators in the job insecurity-job attitudes link.

PubMed

Debus, Maike E; Probst, Tahira M; König, Cornelius J; Kleinmann, Martin

2012-05-01

Job insecurity is related to many detrimental outcomes, with reduced job satisfaction and affective organizational commitment being the 2 most prominent reactions. Yet, effect sizes vary greatly, suggesting the presence of moderator variables. On the basis of Lazarus's cognitive appraisal theory, we assumed that country-level enacted uncertainty avoidance and a country's social safety net would affect an individual's appraisal of job insecurity. More specifically, we hypothesized that these 2 country-level variables would buffer the negative relationships between job insecurity and the 2 aforementioned job attitudes. Combining 3 different data sources, we tested the hypotheses in a sample of 15,200 employees from 24 countries by applying multilevel modeling. The results confirmed the hypotheses that both enacted uncertainty avoidance and the social safety net act as cross-level buffer variables. Furthermore, our data revealed that the 2 cross-level interactions share variance in explaining the 2 job attitudes. Our study responds to calls to look at stress processes from a multilevel perspective and highlights the potential importance of governmental regulation when it comes to individual stress processes. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

Modulation of brain activity by multiple lexical and word form variables in visual word recognition: A parametric fMRI study.

PubMed

Hauk, Olaf; Davis, Matthew H; Pulvermüller, Friedemann

2008-09-01

Psycholinguistic research has documented a range of variables that influence visual word recognition performance. Many of these variables are highly intercorrelated. Most previous studies have used factorial designs, which do not exploit the full range of values available for continuous variables, and are prone to skewed stimulus selection as well as to effects of the baseline (e.g. when contrasting words with pseudowords). In our study, we used a parametric approach to study the effects of several psycholinguistic variables on brain activation. We focussed on the variable word frequency, which has been used in numerous previous behavioural, electrophysiological and neuroimaging studies, in order to investigate the neuronal network underlying visual word processing. Furthermore, we investigated the variable orthographic typicality as well as a combined variable for word length and orthographic neighbourhood size (N), for which neuroimaging results are still either scarce or inconsistent. Data were analysed using multiple linear regression analysis of event-related fMRI data acquired from 21 subjects in a silent reading paradigm. The frequency variable correlated negatively with activation in left fusiform gyrus, bilateral inferior frontal gyri and bilateral insulae, indicating that word frequency can affect multiple aspects of word processing. N correlated positively with brain activity in left and right middle temporal gyri as well as right inferior frontal gyrus. Thus, our analysis revealed multiple distinct brain areas involved in visual word processing within one data set.

Methodological development for selection of significant predictors explaining fatal road accidents.

PubMed

Dadashova, Bahar; Arenas-Ramírez, Blanca; Mira-McWilliams, José; Aparicio-Izquierdo, Francisco

2016-05-01

Identification of the most relevant factors for explaining road accident occurrence is an important issue in road safety research, particularly for future decision-making processes in transport policy. However model selection for this particular purpose is still an ongoing research. In this paper we propose a methodological development for model selection which addresses both explanatory variable and adequate model selection issues. A variable selection procedure, TIM (two-input model) method is carried out by combining neural network design and statistical approaches. The error structure of the fitted model is assumed to follow an autoregressive process. All models are estimated using Markov Chain Monte Carlo method where the model parameters are assigned non-informative prior distributions. The final model is built using the results of the variable selection. For the application of the proposed methodology the number of fatal accidents in Spain during 2000-2011 was used. This indicator has experienced the maximum reduction internationally during the indicated years thus making it an interesting time series from a road safety policy perspective. Hence the identification of the variables that have affected this reduction is of particular interest for future decision making. The results of the variable selection process show that the selected variables are main subjects of road safety policy measures. Published by Elsevier Ltd.

Potential interactions among linguistic, autonomic, and motor factors in speech.

PubMed

Kleinow, Jennifer; Smith, Anne

2006-05-01

Though anecdotal reports link certain speech disorders to increases in autonomic arousal, few studies have described the relationship between arousal and speech processes. Additionally, it is unclear how increases in arousal may interact with other cognitive-linguistic processes to affect speech motor control. In this experiment we examine potential interactions between autonomic arousal, linguistic processing, and speech motor coordination in adults and children. Autonomic responses (heart rate, finger pulse volume, tonic skin conductance, and phasic skin conductance) were recorded simultaneously with upper and lower lip movements during speech. The lip aperture variability (LA variability index) across multiple repetitions of sentences that varied in length and syntactic complexity was calculated under low- and high-arousal conditions. High arousal conditions were elicited by performance of the Stroop color word task. Children had significantly higher lip aperture variability index values across all speaking tasks, indicating more variable speech motor coordination. Increases in syntactic complexity and utterance length were associated with increases in speech motor coordination variability in both speaker groups. There was a significant effect of Stroop task, which produced increases in autonomic arousal and increased speech motor variability in both adults and children. These results provide novel evidence that high arousal levels can influence speech motor control in both adults and children. (c) 2006 Wiley Periodicals, Inc.

Investigation of clinical pharmacokinetic variability of an opioid antagonist through physiologically based absorption modeling.

PubMed

Ding, Xuan; He, Minxia; Kulkarni, Rajesh; Patel, Nita; Zhang, Xiaoyu

2013-08-01

Identifying the source of inter- and/or intrasubject variability in pharmacokinetics (PK) provides fundamental information in understanding the pharmacokinetics-pharmacodynamics relationship of a drug and project its efficacy and safety in clinical populations. This identification process can be challenging given that a large number of potential causes could lead to PK variability. Here we present an integrated approach of physiologically based absorption modeling to investigate the root cause of unexpectedly high PK variability of a Phase I clinical trial drug. LY2196044 exhibited high intersubject variability in the absorption phase of plasma concentration-time profiles in humans. This could not be explained by in vitro measurements of drug properties and excellent bioavailability with low variability observed in preclinical species. GastroPlus™ modeling suggested that the compound's optimal solubility and permeability characteristics would enable rapid and complete absorption in preclinical species and in humans. However, simulations of human plasma concentration-time profiles indicated that despite sufficient solubility and rapid dissolution of LY2196044 in humans, permeability and/or transit in the gastrointestinal (GI) tract may have been negatively affected. It was concluded that clinical PK variability was potentially due to the drug's antagonism on opioid receptors that affected its transit and absorption in the GI tract. Copyright © 2013 Wiley Periodicals, Inc.

Impact of Hydrologic Variability on Ecosystem Dynamics and the Sustainable Use of Soil and Water Resources

NASA Astrophysics Data System (ADS)

Porporato, A. M.

2013-05-01

We discuss the key processes by which hydrologic variability affects the probabilistic structure of soil moisture dynamics in water-controlled ecosystems. These in turn impact biogeochemical cycling and ecosystem structure through plant productivity and biodiversity as well as nitrogen availability and soil conditions. Once the long-term probabilistic structure of these processes is quantified, the results become useful to understand the impact of climatic changes and human activities on ecosystem services, and can be used to find optimal strategies of water and soil resources management under unpredictable hydro-climatic fluctuations. Particular applications regard soil salinization, phytoremediation and optimal stochastic irrigation.

Comparing the Use of Evidence and Culture in Targeted Colorectal Cancer Communication for African Americans

PubMed Central

Thompson, Vetta L. Sanders; Kalesan, Bindu; Wells, Anjanette; Williams, Sha-Lai; Caito, Nicole M.

2010-01-01

Objective This study examined the effects (affective reactions, cognitive reactions and processing, perceived benefits and barriers and intent to screen) of targeted Peripheral + Evidential (PE) and Peripheral+Evidential+Socio-cultural (PE+SC) colorectal cancer communications. Methods This study was a two-arm randomized control study of cancer communication effects on affective, cognitive processing, and behavioral outcomes over a 22-week intervention. There were 771 African American participants, 45 to 75 years, participating in the baseline survey related to CRC screening. Three follow-up interviews that assessed intervention effects on affective response to the publications, cognitive processing, and intent to obtain CRC screening were completed. Results There were no statistically significant differences between PE and PE+SC intervention groups for affect, cognitive processing or intent to screen. However, there were significant interactions effects on outcome variables. Conclusions The advantages and disadvantages of PE+SC targeted cancer communications and implications of sex differences are considered. Practice Implications While there do not appear to be significant differences in behavioral outcomes when using PE and PE+SC strategies, there appear to be subtle differences in affective and cognitive processing outcomes related to medical suspicion and ethnic identity, particularly as it relates to gender. PMID:20702056

Comparing the use of evidence and culture in targeted colorectal cancer communication for African Americans.

PubMed

Thompson, Vetta L Sanders; Kalesan, Bindu; Wells, Anjanette; Williams, Sha-Lai; Caito, Nicole M

2010-12-01

This study examined the effects (affective reactions, cognitive reactions and processing, perceived benefits and barriers and intent to screen) of targeted peripheral+evidential (PE) and peripheral+evidential+socio-cultural (PE+SC) colorectal cancer communications. This study was a two-arm randomized control study of cancer communication effects on affective, cognitive processing, and behavioral outcomes over a 22-week intervention. There were 771 African American participants, 45-75 years, participating in the baseline survey related to CRC screening. Three follow-up interviews that assessed intervention effects on affective response to the publications, cognitive processing, and intent to obtain CRC screening were completed. There were no statistically significant differences between PE and PE+SC intervention groups for affect, cognitive processing or intent to screen. However, there were significant interactions effects on outcome variables. The advantages and disadvantages of PE+SC targeted cancer communications and implications of sex differences are considered. While there do not appear to be significant differences in behavioral outcomes when using PE and PE+SC strategies, there appear to be subtle differences in affective and cognitive processing outcomes related to medical suspicion and ethnic identity, particularly as it relates to gender. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Statistical Study to Evaluate the Effect of Processing Variables on Shrinkage Incidence During Solidification of Nodular Cast Irons

NASA Astrophysics Data System (ADS)

Gutiérrez, J. M.; Natxiondo, A.; Nieves, J.; Zabala, A.; Sertucha, J.

2017-04-01

The study of shrinkage incidence variations in nodular cast irons is an important aspect of manufacturing processes. These variations change the feeding requirements on castings and the optimization of risers' size is consequently affected when avoiding the formation of shrinkage defects. The effect of a number of processing variables on the shrinkage size has been studied using a layout specifically designed for this purpose. The β parameter has been defined as the relative volume reduction from the pouring temperature up to the room temperature. It is observed that shrinkage size and β decrease as effective carbon content increases and when inoculant is added in the pouring stream. A similar effect is found when the parameters selected from cooling curves show high graphite nucleation during solidification of cast irons for a given inoculation level. Pearson statistical analysis has been used to analyze the correlations among all involved variables and a group of Bayesian networks have been subsequently built so as to get the best accurate model for predicting β as a function of the input processing variables. The developed models can be used in foundry plants to study the shrinkage incidence variations in the manufacturing process and to optimize the related costs.

A comparative study of job satisfaction among nurses, psychologists/psychotherapists and social workers working in Quebec mental health teams.

PubMed

Fleury, Marie-Josée; Grenier, Guy; Bamvita, Jean-Marie

2017-01-01

This study identified multiple socio-professional and team effectiveness variables, based on the Input-Mediator-Output-Input (IMOI) model, and tested their associations with job satisfaction for three categories of mental health professionals (nurses, psychologists/psychotherapists, and social workers). Job satisfaction was assessed with the Job Satisfaction Survey. Independent variables were classified into four categories: 1) Socio-professional Characteristics; 2) Team Attributes; 3) Team Processes; and 4) Team Emergent States. Variables were entered successively, by category, into a hierarchical regression model. Team Processes contributed the greatest number of variables to job satisfaction among all professional groups, including team support which was the only significant variable common to all three types of professionals. Greater involvement in the decision-making process, and lower levels of team conflict (Team Processes) were associated with job satisfaction among nurses and social workers. Lower seniority on team (Socio-professional Characteristics), and team collaboration (Team Processes) were associated with job satisfaction among nurses, as was belief in the advantages of interdisciplinary collaboration (Team Emergent States) among psychologists. Knowledge sharing (Team Processes) and affective commitment to the team (Team Emergent States) were associated with job satisfaction among social workers. Results suggest the need for mental health decision-makers and team managers to offer adequate support to mental health professionals, to involve nurses and social workers in the decision-making process, and implement procedures and mechanisms favourable to the prevention or resolution of team conflict with a view toward increasing job satisfaction among mental health professionals.

National climate assessment technical report on the impacts of climate and land use and land cover change

USGS Publications Warehouse

Loveland, Thomas; Mahmood, Rezaul; Patel-Weynand, Toral; Karstensen, Krista; Beckendorf, Kari; Bliss, Norman; Carleton, Andrew

2012-01-01

This technical report responds to the recognition by the U.S. Global Change Research Program (USGCRP) and the National Climate Assessment (NCA) of the importance of understanding how land use and land cover (LULC) affects weather and climate variability and change and how that variability and change affects LULC. Current published, peer-reviewed, scientific literature and supporting data from both existing and original sources forms the basis for this report's assessment of the current state of knowledge regarding land change and climate interactions. The synthesis presented herein documents how current and future land change may alter environment processes and in turn, how those conditions may affect both land cover and land use by specifically investigating, * The primary contemporary trends in land use and land cover, * The land-use and land-cover sectors and regions which are most affected by weather and climate variability,* How land-use practices are adapting to climate change, * How land-use and land-cover patterns and conditions are affecting weather and climate, and * The key elements of an ongoing Land Resources assessment. These findings present information that can be used to better assess land change and climate interactions in order to better assess land management and adaptation strategies for future environmental change and to assist in the development of a framework for an ongoing national assessment.

Processes Affecting Variability of Fluorescence Signals from Benthic Targets in Shallow Waters

DTIC Science & Technology

1997-09-30

processes in the Department of Chemistry at Brookhaven National Laboratory. The model organisms used are primarily cultured zooxanthellae obtained from...and closed (Fm) photosystem II reaction centers in the zooxanthellae isolated from the fire coral, Montipora. The short lifetime curve corresponds...individual zooxanthellae strains, is highly correlated Figure 2. The correlation between the average fluorescence lifetimes, calculated from a four

Multifractal Properties of Process Control Variables

NASA Astrophysics Data System (ADS)

Domański, Paweł D.

2017-06-01

Control system is an inevitable element of any industrial installation. Its quality affects overall process performance significantly. The assessment, whether control system needs any improvement or not, requires relevant and constructive measures. There are various methods, like time domain based, Minimum Variance, Gaussian and non-Gaussian statistical factors, fractal and entropy indexes. Majority of approaches use time series of control variables. They are able to cover many phenomena. But process complexities and human interventions cause effects that are hardly visible for standard measures. It is shown that the signals originating from industrial installations have multifractal properties and such an analysis may extend standard approach to further observations. The work is based on industrial and simulation data. The analysis delivers additional insight into the properties of control system and the process. It helps to discover internal dependencies and human factors, which are hardly detectable.

Hemispheric specialization in affective responses, cerebral dominance for language, and handedness: Lateralization of emotion, language, and dexterity.

PubMed

Costanzo, Elsa Yolanda; Villarreal, Mirta; Drucaroff, Lucas Javier; Ortiz-Villafañe, Manuel; Castro, Mariana Nair; Goldschmidt, Micaela; Wainsztein, Agustina Edith; Ladrón-de-Guevara, María Soledad; Romero, Carlos; Brusco, Luis Ignacio; Camprodon, Joan A; Nemeroff, Charles; Guinjoan, Salvador Martín

2015-07-15

Hemispheric specialization in affective responses has received little attention in the literature. This is a fundamental variable to understand circuit dynamics of networks subserving emotion. In this study we put to test a modified "valence" hypothesis of emotion processing, considering that sadness and happiness are processed by each hemisphere in relation to dominance for language and handedness. Mood induction and language activation during functional magnetic resonance imaging (fMRI) were used in 20 right-handed and 20 nonright-handed subjects, focusing on interconnected regions known to play critical roles in affective responses: subgenual cingulate cortex, amygdala, and anterior insular cortex. We observed a consistent relationship between lateralization of affective processing, motor dexterity, and language in individuals with clear right-handedness. Sadness induces a greater activation of right-hemisphere cortical structures in right-handed, left-dominant individuals, which is not evident in nonright-handed subjects who show no consistent hemispheric dominance for language. In anterior insula, right-handed individuals displayed reciprocal activation of either hemisphere depending upon mood valence, whereas amygdala activation was predominantly left-sided regardless of mood valence. Nonright-handed individuals exhibited less consistent brain lateralization of affective processing regardless of language and motor dexterity lateralization. In contrast with traditional views on emotion processing lateralization, hemispheric specialization in affective responses is not a unitary process but is specific to the brain structure being activated. Copyright © 2015 Elsevier B.V. All rights reserved.

Effects of Attention and Levels of Processing on Explicit and Implicit Memory Function with Interesting and Uninteresting Tasks in University Students

NASA Astrophysics Data System (ADS)

Mahdavian, Alireza; Kormi-Nouri, Reza

This study aims to investigate the effect of attention and levels of processing on memory function and recalling words in two situations when students are interested in the subject and when they are not. This is an experimental study of 160 students conducted individually using a computer software. Results reveal focused attention, interest in the subject and deep processing caused the explicit memory to be at its highest level of functionality. On the contrary, shallow processing, divided attention and lack of interest in the subject plunged memory function into its lowest levels. Variables have different effects on attention, explicit and implicit memory. That is, interesting tasks with focused attention and deep processing have the highest effect on explicit memory in order. Also, interesting tasks, focused attention, respectively affect implicit memory. But level of processing does not affect implicit memory significantly.

Climate Controls AM Fungal Distributions from Global to Local Scales

NASA Astrophysics Data System (ADS)

Kivlin, S. N.; Hawkes, C.; Muscarella, R.; Treseder, K. K.; Kazenel, M.; Lynn, J.; Rudgers, J.

2016-12-01

Arbuscular mycorrhizal (AM) fungi have key functions in terrestrial biogeochemical processes; thus, determining the relative importance of climate, edaphic factors, and plant community composition on their geographic distributions can improve predictions of their sensitivity to global change. Local adaptation by AM fungi to plant hosts, soil nutrients, and climate suggests that all of these factors may control fungal geographic distributions, but their relative importance is unknown. We created species distribution models for 142 AM fungal taxa at the global scale with data from GenBank. We compared climate variables (BioClim and soil moisture), edaphic variables (phosphorus, carbon, pH, and clay content), and plant variables using model selection on models with (1) all variables, (2) climatic variables only (including soil moisture) and (3) resource-related variables only (all other soil parameters and NPP) using the MaxEnt algorithm evaluated with ENMEval. We also evaluated whether drivers of AM fungal distributions were phylogenetically conserved. To test whether global correlates of AM fungal distributions were reflected at local scales, we then surveyed AM fungi in nine plant hosts along three elevation gradients in the Upper Gunnison Basin, Colorado, USA. At the global scale, the distributions of 55% of AM fungal taxa were affected by both climate and soil resources, whereas 16% were only affected by climate and 29% were only affected by soil resources. Even for AM fungi that were affected by both climate and resources, the effects of climatic variables nearly always outweighed those of resources. Soil moisture and isothermality were the main climatic and NPP and soil carbon the main resource related factors influencing AM fungal distributions. Distributions of closely related AM fungal taxa were similarly affected by climate, but not by resources. Local scale surveys of AM fungi across elevations confirmed that climate was a key driver of AM fungal composition and root colonization, with weaker influences of plant identity and soil nutrients. These two studies across scales suggest prevailing effects of climate on AM fungal distributions. Thus, incorporating climate when forecasting future ranges of AM fungi will enhance predictions of AM fungal abundance and associated ecosystem functions.

Control of plasma process by use of harmonic frequency components of voltage and current

DOEpatents

Miller, Paul A.; Kamon, Mattan

1994-01-01

The present invention provides for a technique for taking advantage of the intrinsic electrical non-linearity of processing plasmas to add additional control variables that affect process performance. The technique provides for the adjustment of the electrical coupling circuitry, as well as the electrical excitation level, in response to measurements of the reactor voltage and current and to use that capability to modify the plasma characteristics to obtain the desired performance.

How Do Land-Use and Climate Change Affect Watershed Health? A Scenario-Based Analysis

EPA Science Inventory

With the growing emphasis on biofuel crops and potential impacts of climate variability and change, there is a need to quantify their effects on hydrological processes for developing watershed management plans. Environmental consequences are currently estimated by utilizing comp...

A study on the risk perception of light pollution and the process of social amplification of risk in Korea.

PubMed

Kim, Kyung Hee; Choi, Jae Wook; Lee, Eunil; Cho, Yong Min; Ahn, Hyung Rae

2015-05-01

In this study, the risk perception level of each light pollution type was analyzed, and the effects of the variables (e.g., psychometric paradigm factor, trust in the government, etc.) on the process of the increase in the risk perception were analyzed. For the sample population (1096 persons) in Korea, the risk perception levels of each light pollution type and other environmental and health risk factors were compared, and the relative magnitude was examined. In addition, to test which variables affect the group with high-risk perception of each light pollution type, a logistic regression analysis was performed. For the group with highest risk perception of light pollution, the odds ratios (OR) of all psychometric paradigms (excluding controllability) increased compared to those of the group with low-risk perception. Additionally, the level showing the acquisition of information from the media and the recollection level of media criticism on each light pollution type showed a statistically significant increase. Especially, the risk perception of light trespass increased as trust in the government decreased. The significance of this study includes the finding that the public's risk perception of light pollution was significantly affected by the psychometric paradigm factors. Moreover, this study analyzed the differences of the variables that affect the increase in the risk perception of each light pollution type and provided a theoretical framework that can practically reflect the strategy for the risk communication of light pollution.

Characteristics, processes, and causes of the spatio-temporal variabilities of the East Asian monsoon system

NASA Astrophysics Data System (ADS)

Huang, Ronghui; Chen, Jilong; Wang, Lin; Lin, Zhongda

2012-09-01

Recent advances in the study of the characteristics, processes, and causes of spatio-temporal variabilities of the East Asian monsoon (EAM) system are reviewed in this paper. The understanding of the EAM system has improved in many aspects: the basic characteristics of horizontal and vertical structures, the annual cycle of the East Asian summer monsoon (EASM) system and the East Asian winter monsoon (EAWM) system, the characteristics of the spatio-temporal variabilities of the EASM system and the EAWM system, and especially the multiple modes of the EAM system and their spatio-temporal variabilities. Some new results have also been achieved in understanding the atmosphere-ocean interaction and atmosphere-land interaction processes that affect the variability of the EAM system. Based on recent studies, the EAM system can be seen as more than a circulation system, it can be viewed as an atmosphere-ocean-land coupled system, namely, the EAM climate system. In addition, further progress has been made in diagnosing the internal physical mechanisms of EAM climate system variability, especially regarding the characteristics and properties of the East Asia-Pacific (EAP) teleconnection over East Asia and the North Pacific, the "Silk Road" teleconnection along the westerly jet stream in the upper troposphere over the Asian continent, and the dynamical effects of quasi-stationary planetary wave activity on EAM system variability. At the end of the paper, some scientific problems regarding understanding the EAM system variability are proposed for further study.

Stochastic analysis of multiphase flow in porous media: II. Numerical simulations

NASA Astrophysics Data System (ADS)

Abin, A.; Kalurachchi, J. J.; Kemblowski, M. W.; Chang, C.-M.

1996-08-01

The first paper (Chang et al., 1995b) of this two-part series described the stochastic analysis using spectral/perturbation approach to analyze steady state two-phase (water and oil) flow in a, liquid-unsaturated, three fluid-phase porous medium. In this paper, the results between the numerical simulations and closed-form expressions obtained using the perturbation approach are compared. We present the solution to the one-dimensional, steady-state oil and water flow equations. The stochastic input processes are the spatially correlated logk where k is the intrinsic permeability and the soil retention parameter, α. These solutions are subsequently used in the numerical simulations to estimate the statistical properties of the key output processes. The comparison between the results of the perturbation analysis and numerical simulations showed a good agreement between the two methods over a wide range of logk variability with three different combinations of input stochastic processes of logk and soil parameter α. The results clearly demonstrated the importance of considering the spatial variability of key subsurface properties under a variety of physical scenarios. The variability of both capillary pressure and saturation is affected by the type of input stochastic process used to represent the spatial variability. The results also demonstrated the applicability of perturbation theory in predicting the system variability and defining effective fluid properties through the ergodic assumption.

Large deviation probabilities for correlated Gaussian stochastic processes and daily temperature anomalies

NASA Astrophysics Data System (ADS)

Massah, Mozhdeh; Kantz, Holger

2016-04-01

As we have one and only one earth and no replicas, climate characteristics are usually computed as time averages from a single time series. For understanding climate variability, it is essential to understand how close a single time average will typically be to an ensemble average. To answer this question, we study large deviation probabilities (LDP) of stochastic processes and characterize them by their dependence on the time window. In contrast to iid variables for which there exists an analytical expression for the rate function, the correlated variables such as auto-regressive (short memory) and auto-regressive fractionally integrated moving average (long memory) processes, have not an analytical LDP. We study LDP for these processes, in order to see how correlation affects this probability in comparison to iid data. Although short range correlations lead to a simple correction of sample size, long range correlations lead to a sub-exponential decay of LDP and hence to a very slow convergence of time averages. This effect is demonstrated for a 120 year long time series of daily temperature anomalies measured in Potsdam (Germany).

75 FR 9626 - Notice of Issuance of Regulatory Guide

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-03

... maintain variables and systems that can affect the fission process, the integrity of the reactor core, the... on some other defined basis. GDC 24 requires that interconnection of the protection and control..., Regulatory Guide Development Branch, Division of Engineering, Office of Nuclear Regulatory Research. [FR Doc...

Motivational Effects on Self-Regulated Learning with Different Tasks

ERIC Educational Resources Information Center

Vollmeyer, Regina; Rheinberg, Falko

2006-01-01

In our cognitive motivational process model (Vollmeyer & Rheinberg, "Zeitschrift fur Padagogische Psychologie," 12:11-23, 1998) we assume that initial motivation affects performance via motivation during learning and learning strategies. These variables are also central for self-regulation theories (e.g., M. Boekaerts, "European Psychologist,"…

Application of Spaceborne Scatterometer for Mapping Freeze-Thaw State in Northern Landscapes as a Measure of Ecological and Hydrological Processes

NASA Technical Reports Server (NTRS)

McDonald, Kyle; Kimball, John; Zimmermann, Reiner; Way, JoBea; Frolking, Steve; Running, Steve

1994-01-01

Landscape freeze/thaw transitions coincide with marked shifts in albedo, surface energy and mass exchange, and associated snow dynamics. monitoring landscape freeze/thaw dynamics would improve our ability to quantify the interannual variability of boreal hydrology and river runoff/flood dynamics, The annual duration of frost-free period also bounds the period of photosynthetic activity in borel and arctic regions thus affecting the carbon budget and the interannual variability fo regional carbon fluxes.

Cross-scale impact of climate temporal variability on ecosystem water and carbon fluxes

DOE PAGES

Paschalis, Athanasios; Fatichi, Simone; Katul, Gabriel G.; ...

2015-08-07

While the importance of ecosystem functioning is undisputed in the context of climate change and Earth system modeling, the role of short-scale temporal variability of hydrometeorological forcing (~1 h) on the related ecosystem processes remains to be fully understood. Additionally, various impacts of meteorological forcing variability on water and carbon fluxes across a range of scales are explored here using numerical simulations. Synthetic meteorological drivers that highlight dynamic features of the short temporal scale in series of precipitation, temperature, and radiation are constructed. These drivers force a mechanistic ecohydrological model that propagates information content into the dynamics of water andmore » carbon fluxes for an ensemble of representative ecosystems. The focus of the analysis is on a cross-scale effect of the short-scale forcing variability on the modeled evapotranspiration and ecosystem carbon assimilation. Interannual variability of water and carbon fluxes is emphasized in the analysis. The main study inferences are summarized as follows: (a) short-scale variability of meteorological input does affect water and carbon fluxes across a wide range of time scales, spanning from the hourly to the annual and longer scales; (b) different ecosystems respond to the various characteristics of the short-scale variability of the climate forcing in various ways, depending on dominant factors limiting system productivity; (c) whenever short-scale variability of meteorological forcing influences primarily fast processes such as photosynthesis, its impact on the slow-scale variability of water and carbon fluxes is small; and (d) whenever short-scale variability of the meteorological forcing impacts slow processes such as movement and storage of water in the soil, the effects of the variability can propagate to annual and longer time scales.« less

Cross-scale impact of climate temporal variability on ecosystem water and carbon fluxes

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

Paschalis, Athanasios; Fatichi, Simone; Katul, Gabriel G.

While the importance of ecosystem functioning is undisputed in the context of climate change and Earth system modeling, the role of short-scale temporal variability of hydrometeorological forcing (~1 h) on the related ecosystem processes remains to be fully understood. Additionally, various impacts of meteorological forcing variability on water and carbon fluxes across a range of scales are explored here using numerical simulations. Synthetic meteorological drivers that highlight dynamic features of the short temporal scale in series of precipitation, temperature, and radiation are constructed. These drivers force a mechanistic ecohydrological model that propagates information content into the dynamics of water andmore » carbon fluxes for an ensemble of representative ecosystems. The focus of the analysis is on a cross-scale effect of the short-scale forcing variability on the modeled evapotranspiration and ecosystem carbon assimilation. Interannual variability of water and carbon fluxes is emphasized in the analysis. The main study inferences are summarized as follows: (a) short-scale variability of meteorological input does affect water and carbon fluxes across a wide range of time scales, spanning from the hourly to the annual and longer scales; (b) different ecosystems respond to the various characteristics of the short-scale variability of the climate forcing in various ways, depending on dominant factors limiting system productivity; (c) whenever short-scale variability of meteorological forcing influences primarily fast processes such as photosynthesis, its impact on the slow-scale variability of water and carbon fluxes is small; and (d) whenever short-scale variability of the meteorological forcing impacts slow processes such as movement and storage of water in the soil, the effects of the variability can propagate to annual and longer time scales.« less

Mindfulness based cognitive therapy may improve emotional processing in bipolar disorder: pilot ERP and HRV study.

PubMed

Howells, Fleur M; Laurie Rauch, H G; Ives-Deliperi, Victoria L; Horn, Neil R; Stein, Dan J

2014-06-01

Emotional processing in bipolar disorder (BD) is impaired. We aimed to measure the effects of mindfulness based cognitive-behavioral therapy (MBCT) in BD on emotional processing, as measured by event related potentials (ERP) and by heart rate variability (HRV). ERP and HRV were recorded during the completion of a visual matching task, which included object matching, affect matching, and affect labeling. Individuals with BD (n = 12) were compared with controls (n = 9) to obtain baseline data prior to the individuals with BD undergoing an 8-week MBCT intervention. ERP and HRV recording was repeated after the MBCT intervention in BD. Participants with BD had exaggerated ERP N170 amplitude and increased HRV HF peak compared to controls, particularly during the affect matching condition. After an 8-week MBCT intervention, participants with BD showed attenuation of ERP N170 amplitude and reduced HRV HF peak. Our findings support findings from the literature emphasizing that emotional processing in BD is altered, and suggesting that MBCT may improve emotional processing in BD.

Haploinsufficiency of the NF-κB1 Subunit p50 in Common Variable Immunodeficiency.

PubMed

Fliegauf, Manfred; Bryant, Vanessa L; Frede, Natalie; Slade, Charlotte; Woon, See-Tarn; Lehnert, Klaus; Winzer, Sandra; Bulashevska, Alla; Scerri, Thomas; Leung, Euphemia; Jordan, Anthony; Keller, Baerbel; de Vries, Esther; Cao, Hongzhi; Yang, Fang; Schäffer, Alejandro A; Warnatz, Klaus; Browett, Peter; Douglass, Jo; Ameratunga, Rohan V; van der Meer, Jos W M; Grimbacher, Bodo

2015-09-03

Common variable immunodeficiency (CVID), characterized by recurrent infections, is the most prevalent symptomatic antibody deficiency. In ∼90% of CVID-affected individuals, no genetic cause of the disease has been identified. In a Dutch-Australian CVID-affected family, we identified a NFKB1 heterozygous splice-donor-site mutation (c.730+4A>G), causing in-frame skipping of exon 8. NFKB1 encodes the transcription-factor precursor p105, which is processed to p50 (canonical NF-κB pathway). The altered protein bearing an internal deletion (p.Asp191_Lys244delinsGlu; p105ΔEx8) is degraded, but is not processed to p50ΔEx8. Altered NF-κB1 proteins were also undetectable in a German CVID-affected family with a heterozygous in-frame exon 9 skipping mutation (c.835+2T>G) and in a CVID-affected family from New Zealand with a heterozygous frameshift mutation (c.465dupA) in exon 7. Given that residual p105 and p50—translated from the non-mutated alleles—were normal, and altered p50 proteins were absent, we conclude that the CVID phenotype in these families is caused by NF-κB1 p50 haploinsufficiency. Copyright © 2015 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

Langevin dynamics for vector variables driven by multiplicative white noise: A functional formalism

NASA Astrophysics Data System (ADS)

Moreno, Miguel Vera; Arenas, Zochil González; Barci, Daniel G.

2015-04-01

We discuss general multidimensional stochastic processes driven by a system of Langevin equations with multiplicative white noise. In particular, we address the problem of how time reversal diffusion processes are affected by the variety of conventions available to deal with stochastic integrals. We present a functional formalism to build up the generating functional of correlation functions without any type of discretization of the Langevin equations at any intermediate step. The generating functional is characterized by a functional integration over two sets of commuting variables, as well as Grassmann variables. In this representation, time reversal transformation became a linear transformation in the extended variables, simplifying in this way the complexity introduced by the mixture of prescriptions and the associated calculus rules. The stochastic calculus is codified in our formalism in the structure of the Grassmann algebra. We study some examples such as higher order derivative Langevin equations and the functional representation of the micromagnetic stochastic Landau-Lifshitz-Gilbert equation.

Potential Impact of North Atlantic Climate Variability on Ocean Biogeochemical Processes

NASA Astrophysics Data System (ADS)

Liu, Y.; Muhling, B.; Lee, S. K.; Muller-Karger, F. E.; Enfield, D. B.; Lamkin, J. T.; Roffer, M. A.

2016-02-01

Previous studies have shown that upper ocean circulations largely determine primary production in the euphotic layers, here the global ocean model with biogeochemistry (GFDL's Modular Ocean Model with TOPAZ biogeochemistry) forced with the ERA-Interim is used to simulate the natural variability of biogeochemical processes in global ocean during 1979-present. Preliminary results show that the surface chlorophyll is overall underestimated in MOM-TOPAZ, but its spatial pattern is fairly realistic. Relatively high chlorophyll variability is shown in the subpolar North Atlantic, northeastern tropical Atlantic, and equatorial Atlantic. Further analysis suggests that the chlorophyll variability in the North Atlantic Ocean is affected by long-term climate variability. For the subpolar North Atlantic region, the chlorophyll variability is light-limited and is significantly correlated with North Atlantic Oscillation. A dipole pattern of chlorophyll variability is found between the northeastern tropical Atlantic and equatorial Atlantic. For the northeastern North Atlantic, the chlorophyll variability is significantly correlated with Atlantic Meridional Mode (AMM) and Atlantic Multidecadal Oscillation (AMO). During the negative phase of AMM and AMO, the increased trade wind in the northeast North Atlantic can lead to increased upwelling of nutrients. In the equatorial Atlantic region, the chlorophyll variability is largely link to Atlantic-Niño and associated equatorial upwelling of nutrients. The potential impact of climate variability on the distribution of pelagic fishes (i.e. yellowfin tuna) are discussed.

The Extent to Which Principals' Leadership and Decision-Making Processes Exerts Influence on the Operations of Inclusion Classrooms Including Students with Autism Spectrum Disorder at the Elementary School Level

ERIC Educational Resources Information Center

Bermani, Michelle Ines

2017-01-01

In this quantitative and qualitative mixed study, the researcher focused on a range of factors that drive principals' decision making and examined the variables that affect principals' decision-making. The study assessed the extent to which principals' leadership and decision-making processes exert influence on the operations of inclusion…

The modulation of EEG variability between internally- and externally-driven cognitive states varies with maturation and task performance

PubMed Central

Willatt, Stephanie E.; Cortese, Filomeno; Protzner, Andrea B.

2017-01-01

Increasing evidence suggests that brain signal variability is an important measure of brain function reflecting information processing capacity and functional integrity. In this study, we examined how maturation from childhood to adulthood affects the magnitude and spatial extent of state-to-state transitions in brain signal variability, and how this relates to cognitive performance. We looked at variability changes between resting-state and task (a symbol-matching task with three levels of difficulty), and within trial (fixation, post-stimulus, and post-response). We calculated variability with multiscale entropy (MSE), and additionally examined spectral power density (SPD) from electroencephalography (EEG) in children aged 8–14, and in adults aged 18–33. Our results suggest that maturation is characterized by increased local information processing (higher MSE at fine temporal scales) and decreased long-range interactions with other neural populations (lower MSE at coarse temporal scales). Children show MSE changes that are similar in magnitude, but greater in spatial extent when transitioning between internally- and externally-driven brain states. Additionally, we found that in children, greater changes in task difficulty were associated with greater magnitude of modulation in MSE. Our results suggest that the interplay between maturational and state-to-state changes in brain signal variability manifest across different spatial and temporal scales, and influence information processing capacity in the brain. PMID:28750035

A soil-landscape framework for understanding spatial and temporal variability in biogeochemical processes in catchments

NASA Astrophysics Data System (ADS)

McGuire, K. J.; Bailey, S. W.; Ross, D. S.

2017-12-01

Heterogeneity in biophysical properties within catchments challenges how we quantify and characterize biogeochemical processes and interpret catchment outputs. Interactions between the spatiotemporal variability of hydrological states and fluxes and soil development can spatially structure catchments, leading to a framework for understanding patterns in biogeochemical processes. In an upland, glaciated landscape at the Hubbard Brook Experimental Forest (HBEF) in New Hampshire, USA, we are embracing the structure and organization of soils to understand the spatial relations between runoff production zones, distinct soil-biogeochemical environments, and solute retention and release. This presentation will use observations from the HBEF to demonstrate that a soil-landscape framework is essential in understanding the spatial and temporal variability of biogeochemical processes in this catchment. Specific examples will include how laterally developed soils reveal the location of active runoff production zones and lead to gradients in primary mineral dissolution and the distribution of weathering products along hillslopes. Soil development patterns also highlight potential carbon and nitrogen cycling hotspots, differentiate acidic conditions, and affect the regulation of surface water quality. Overall, this work demonstrates the importance of understanding the landscape-level structural organization of soils in characterizing the variation and extent of biogeochemical processes that occur in catchments.

Job satisfaction among mental healthcare professionals: The respective contributions of professional characteristics, team attributes, team processes, and team emergent states.

PubMed

Fleury, Marie-Josée; Grenier, Guy; Bamvita, Jean-Marie

2017-01-01

The aim of this study was to determine the respective contribution of professional characteristics, team attributes, team processes, and team emergent states on the job satisfaction of 315 mental health professionals from Quebec (Canada). Job satisfaction was measured with the Job Satisfaction Survey. Independent variables were organized into four categories according to a conceptual framework inspired from the Input-Mediator-Outcomes-Input Model. The contribution of each category of variables was assessed using hierarchical regression analysis. Variations in job satisfaction were mostly explained by team processes, with minimal contribution from the other three categories. Among the six variables significantly associated with job satisfaction in the final model, four were team processes: stronger team support, less team conflict, deeper involvement in the decision-making process, and more team collaboration. Job satisfaction was also associated with nursing and, marginally, male gender (professional characteristics) as well as with a stronger affective commitment toward the team (team emergent states). Results confirm the importance for health managers of offering adequate support to mental health professionals, and creating an environment favorable to collaboration and decision-sharing, and likely to reduce conflicts between team members.

Vulnerability to climate change and adaptation strategies of local communities in Malawi: experiences of women fish-processing groups in the Lake Chilwa Basin

NASA Astrophysics Data System (ADS)

Jørstad, Hanne; Webersik, Christian

2016-12-01

In recent years, research on climate change and human security has received much attention among policy makers and academia alike. Communities in the Global South that rely on an intact resource base and struggle with poverty, existing inequalities and historical injustices will especially be affected by predicted changes in temperature and precipitation. The objective of this article is to better understand under what conditions local communities can adapt to anticipated impacts of climate change. The empirical part of the paper answers the question as to what extent local women engaged in fish processing in the Chilwa Basin in Malawi have experienced climate change and how they are affected by it. The article assesses an adaptation project designed to make those women more resilient to a warmer and more variable climate. The research results show that marketing and improving fish processing as strategies to adapt to climate change have their limitations. The study concludes that livelihood diversification can be a more effective strategy for Malawian women to adapt to a more variable and unpredictable climate rather than exclusively relying on a resource base that is threatened by climate change.

Identification of critical formulation and processing variables for metoprolol tartrate extended-release (ER) matrix tablets.

PubMed

Rekhi, G S; Nellore, R V; Hussain, A S; Tillman, L G; Malinowski, H J; Augsburger, L L

1999-06-02

The objective of this study, was to examine the influence of critical formulation and processing variables as described in the AAPS/FDA Workshop II report on scale-up of oral extended-release dosage forms, using a hydrophilic polymer hydroxypropyl methylcellulose (Methocel K100LV). A face-centered central composite design (26 runs+3 center points) was selected and the variables studied were: filler ratio (lactose:dicalcium phosphate (50:50)), polymer level (15/32.5/50%), magnesium stearate level (1/1.5/2%), lubricant blend time (2/6/10 min) and compression force (400/600/800 kg). Granulations (1.5 kg, 3000 units) were manufactured using a fluid-bed process, lubricated and tablets (100 mg metoprolol tartrate) were compressed on an instrumented Manesty D3B rotary tablet press. Dissolution tests were performed using USP apparatus 2, at 50 rpm in 900 ml phosphate buffer (pH 6.8). Responses studied included percent drug released at Q1 (1 h), Q4, Q6, Q12. Analysis of variance indicated that change in polymer level was the most significant factor affecting drug release. Increase in dicalcium phosphate level and compression force were found to affect the percent released at the later dissolution time points. Some interaction effects between the variables studied were also found to be statistically significant. The drug release mechanism was predominantly found to be Fickian diffusion controlled (n=0.46-0.59). Response surface plots and regression models were developed which adequately described the experimental space. Three formulations having slow-, medium- and fast-releasing dissolution profiles were identified for a future bioavailability/bioequivalency study. The results of this study provided the framework for further work involving both in vivo studies and scale-up.

Artificial Intelligence Tools for Scaling Up of High Shear Wet Granulation Process.

PubMed

Landin, Mariana

2017-01-01

The results presented in this article demonstrate the potential of artificial intelligence tools for predicting the endpoint of the granulation process in high-speed mixer granulators of different scales from 25L to 600L. The combination of neurofuzzy logic and gene expression programing technologies allowed the modeling of the impeller power as a function of operation conditions and wet granule properties, establishing the critical variables that affect the response and obtaining a unique experimental polynomial equation (transparent model) of high predictability (R 2 > 86.78%) for all size equipment. Gene expression programing allowed the modeling of the granulation process for granulators of similar and dissimilar geometries and can be improved by implementing additional characteristics of the process, as composition variables or operation parameters (e.g., batch size, chopper speed). The principles and the methodology proposed here can be applied to understand and control manufacturing process, using any other granulation equipment, including continuous granulation processes. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Connecting Achievement Motivation to Performance in General Chemistry

ERIC Educational Resources Information Center

Ferrell, Brent; Phillips, Michael M.; Barbera, Jack

2016-01-01

Student success in chemistry is inherently tied to motivational and other affective processes. We investigated three distinct constructs tied to motivation: self-efficacy, interest, and effort beliefs. These variables were measured twice over the course of a semester in three sections of a first-semester general chemistry course (n = 170). We…

Linguistic Parameters in Performance Models.

ERIC Educational Resources Information Center

Mansell, Philip

This paper deals with problems concerning the nature of the input to a phonetic processor. Several assumptions provide the basis for consideration of the problem. There is a phonological level of processing which reflects the sound structure of the language; the rules associated with it are not affected by variables associated either with the…

Utility of computer simulations in landscape genetics

Treesearch

Bryan K. Epperson; Brad H. McRae; Kim Scribner; Samuel A. Cushman; Michael S. Rosenberg; Marie-Josee Fortin; Patrick M. A. James; Melanie Murphy; Stephanie Manel; Pierre Legendre; Mark R. T. Dale

2010-01-01

Population genetics theory is primarily based on mathematical models in which spatial complexity and temporal variability are largely ignored. In contrast, the field of landscape genetics expressly focuses on how population genetic processes are affected by complex spatial and temporal environmental heterogeneity. It is spatially explicit and relates patterns to...

Attitudes of EFL Learners towards the Internet

ERIC Educational Resources Information Center

Aydin, Selami

2007-01-01

Related literature indicates that the Internet has an important role and great potential in foreign language learning. It is also obvious that attitudes of learners affect learning process significantly. This study aimed to investigate the attitudes of foreign language learners and to find the relationship between attitudes and subject variables.…

Processes Affecting the Variability of Fluorescence Signals from Benthic Targets in Shallow Waters

DTIC Science & Technology

1999-09-30

isolated green fluorescent proteins from a variety of cnidarians and characterized their spectral signatures and biochemical characteristics. RESULTS...types of GFP-like fluorophores are present in Cnidarians . The first one had the only excitation band centered at ca. 495 nm; the second type had two

High variability impairs motor learning regardless of whether it affects task performance.

PubMed

Cardis, Marco; Casadio, Maura; Ranganathan, Rajiv

2018-01-01

Motor variability plays an important role in motor learning, although the exact mechanisms of how variability affects learning are not well understood. Recent evidence suggests that motor variability may have different effects on learning in redundant tasks, depending on whether it is present in the task space (where it affects task performance) or in the null space (where it has no effect on task performance). We examined the effect of directly introducing null and task space variability using a manipulandum during the learning of a motor task. Participants learned a bimanual shuffleboard task for 2 days, where their goal was to slide a virtual puck as close as possible toward a target. Critically, the distance traveled by the puck was determined by the sum of the left- and right-hand velocities, which meant that there was redundancy in the task. Participants were divided into five groups, based on both the dimension in which the variability was introduced and the amount of variability that was introduced during training. Results showed that although all groups were able to reduce error with practice, learning was affected more by the amount of variability introduced rather than the dimension in which variability was introduced. Specifically, groups with higher movement variability during practice showed larger errors at the end of practice compared with groups that had low variability during learning. These results suggest that although introducing variability can increase exploration of new solutions, this may adversely affect the ability to retain the learned solution. NEW & NOTEWORTHY We examined the role of introducing variability during motor learning in a redundant task. The presence of redundancy allows variability to be introduced in different dimensions: the task space (where it affects task performance) or the null space (where it does not affect task performance). We found that introducing variability affected learning adversely, but the amount of variability was more critical than the dimension in which variability was introduced.

Mediators of weight loss in a family-based intervention presented over the internet.

PubMed

White, Marney A; Martin, Pamela D; Newton, Robert L; Walden, Heather M; York-Crowe, Emily E; Gordon, Stewart T; Ryan, Donna H; Williamson, Donald A

2004-07-01

To assess the process variables involved in a weight loss program for African-American adolescent girls. Several process variables have been identified as affecting success in in vivo weight loss programs for adults and children, including program adherence, self-efficacy, and social support. The current study sought to broaden the understanding of these process variables as they pertain to an intervention program that is presented using the Internet. It was hypothesized that variables such as program adherence, dietary self-efficacy, psychological factors, and family environment factors would mediate the effect of the experimental condition on weight loss. Participants were 57 adolescent African-American girls who joined the program with one obese parent; family pairs were randomized to either a behavioral or control condition in an Internet-based weight loss program. Outcome data (weight loss) are reported for the first 6 months of the intervention. Results partially supported the hypotheses. For weight loss among adolescents, parent variables pertaining to life and family satisfaction were the strongest mediating variables. For parental weight loss, changes in dietary practices over the course of 6 months were the strongest mediators. The identification of factors that enhance or impede weight loss for adolescents is an important step in improving weight loss programs for this group. The current findings suggest that family/parental variables exert a strong influence on weight loss efforts for adolescents and should be considered in developing future programs. Copyright 2004 NAASO

Systematic review of the neural basis of social cognition in patients with mood disorders.

PubMed

Cusi, Andrée M; Nazarov, Anthony; Holshausen, Katherine; Macqueen, Glenda M; McKinnon, Margaret C

2012-05-01

This review integrates neuroimaging studies of 2 domains of social cognition--emotion comprehension and theory of mind (ToM)--in patients with major depressive disorder and bipolar disorder. The influence of key clinical and method variables on patterns of neural activation during social cognitive processing is also examined. Studies were identified using PsycINFO and PubMed (January 1967 to May 2011). The search terms were "fMRI," "emotion comprehension," "emotion perception," "affect comprehension," "affect perception," "facial expression," "prosody," "theory of mind," "mentalizing" and "empathy" in combination with "major depressive disorder," "bipolar disorder," "major depression," "unipolar depression," "clinical depression" and "mania." Taken together, neuroimaging studies of social cognition in patients with mood disorders reveal enhanced activation in limbic and emotion-related structures and attenuated activity within frontal regions associated with emotion regulation and higher cognitive functions. These results reveal an overall lack of inhibition by higher-order cognitive structures on limbic and emotion-related structures during social cognitive processing in patients with mood disorders. Critically, key variables, including illness burden, symptom severity, comorbidity, medication status and cognitive load may moderate this pattern of neural activation. Studies that did not include control tasks or a comparator group were included in this review. Further work is needed to examine the contribution of key moderator variables and to further elucidate the neural networks underlying altered social cognition in patients with mood disorders. The neural networks under lying higher-order social cognitive processes, including empathy, remain unexplored in patients with mood disorders.

Dimensional control of die castings

NASA Astrophysics Data System (ADS)

Karve, Aniruddha Ajit

The demand for net shape die castings, which require little or no machining, is steadily increasing. Stringent customer requirements are forcing die casters to deliver high quality castings in increasingly short lead times. Dimensional conformance to customer specifications is an inherent part of die casting quality. The dimensional attributes of a die casting are essentially dependent upon many factors--the quality of the die and the degree of control over the process variables being the two major sources of dimensional error in die castings. This study focused on investigating the nature and the causes of dimensional error in die castings. The two major components of dimensional error i.e., dimensional variability and die allowance were studied. The major effort of this study was to qualitatively and quantitatively study the effects of casting geometry and process variables on die casting dimensional variability and die allowance. This was accomplished by detailed dimensional data collection at production die casting sites. Robust feature characterization schemes were developed to describe complex casting geometry in quantitative terms. Empirical modeling was utilized to quantify the effects of the casting variables on dimensional variability and die allowance for die casting features. A number of casting geometry and process variables were found to affect dimensional variability in die castings. The dimensional variability was evaluated by comparisons with current published dimensional tolerance standards. The casting geometry was found to play a significant role in influencing the die allowance of the features measured. The predictive models developed for dimensional variability and die allowance were evaluated to test their effectiveness. Finally, the relative impact of all the components of dimensional error in die castings was put into perspective, and general guidelines for effective dimensional control in the die casting plant were laid out. The results of this study will contribute to enhancement of dimensional quality and lead time compression in the die casting industry, thus making it competitive with other net shape manufacturing processes.

Compounding nonlinearities in the climate and wildfire system contribute to high uncertainty in estimates of future burned area in the western United State

NASA Astrophysics Data System (ADS)

Williams, P.

2015-12-01

Ecological studies are increasingly recognizing the importance of atmospheric vapor-pressure deficit (VPD) as a driver of forest drought stress and disturbance processes such as wildfire. Because of the nonlinear Clausius-Clapeyron relationship between temperature and saturation vapor pressure, small variations in temperature can have large impacts on VPD, and therefore drought, particularly in warm, dry areas and particularly during the warm season. It is also clear that VPD and drought affect forest fire nonlinearly, as incremental drying leads to increasingly large burned areas. Forest fire is also affected by fuel amount and connectivity, which are promoted by vegetation growth in previous years, which is in turn promoted by lack of drought, highlighting the importance of nuances in the sequencing of natural interannual climate variations in modulating the impacts of drought on wildfire. The many factors affecting forest fire, and the nonlinearities embedded within the climate and wildfire systems, cause interannual variability in forest-fire area and frequency to be wildly variable and strongly affected by internal climate variability. In addition, warming over the past century has produced a background increase in forest fire frequency and area in many regions. In this talk I focus on the western United States and will explore whether the relationships between internal climate variability on forest fire area have been amplified by the effects of warming as a result of the compounding nonlinearities described above. I will then explore what this means for future burned area in the western United States and make the case that uncertainties in the future global greenhouse gas emissions trajectory, model projections of mean temperatures, model projections of precipitation, and model projections of natural climate variability translate to very large uncertainties in the effects of future climate variability on forest fire area in the United States and globally.

Examining the sources of variability in cell culture media used for biopharmaceutical production.

PubMed

McGillicuddy, Nicola; Floris, Patrick; Albrecht, Simone; Bones, Jonathan

2018-01-01

Raw materials, in particular cell culture media, represent a significant source of variability to biopharmaceutical manufacturing processes that can detrimentally affect cellular growth, viability and specific productivity or alter the quality profile of the expressed therapeutic protein. The continual expansion of the biopharmaceutical industry is creating an increasing demand on the production and supply chain consistency for cell culture media, especially as companies embrace intensive continuous processing. Here, we provide a historical perspective regarding the transition from serum containing to serum-free media, the development of chemically-defined cell culture media for biopharmaceutical production using industrial scale bioprocesses and review production mechanisms for liquid and powder culture media. An overview and critique of analytical approaches used for the characterisation of cell culture media and the identification of root causes of variability are also provided, including in-depth liquid phase separations, mass spectrometry and spectroscopic methods.

Statistical optimization of lovastatin production by Omphalotus olearius (DC.) singer in submerged fermentation.

PubMed

Atlı, Burcu; Yamaç, Mustafa; Yıldız, Zeki; Isikhuemhen, Omoanghe S

2016-01-01

In this study, culture conditions were optimized to improve lovastatin production by Omphalotus olearius, isolate OBCC 2002, using statistical experimental designs. The Plackett-Burman design was used to select important variables affecting lovastatin production. Accordingly, glucose, peptone, and agitation speed were determined as the variables that have influence on lovastatin production. In a further experiment, these variables were optimized with a Box-Behnken design and applied in a submerged process; this resulted in 12.51 mg/L lovastatin production on a medium containing glucose (10 g/L), peptone (5 g/L), thiamine (1 mg/L), and NaCl (0.4 g/L) under static conditions. This level of lovastatin production is eight times higher than that produced under unoptimized media and growth conditions by Omphalotus olearius. To the best of our knowledge, this is the first attempt to optimize submerged fermentation process for lovastatin production by Omphalotus olearius.

Analysis of Setting Efficacy in Young Male and Female Volleyball Players.

PubMed

González-Silva, Jara; Domínguez, Alberto Moreno; Fernández-Echeverría, Carmen; Rabaz, Fernando Claver; Arroyo, M Perla Moreno

2016-12-01

The main objective of this study was to analyse the variables that predicted setting efficacy in complex I (KI) in volleyball, in formative categories and depending on gender. The study sample was comprised of 5842 game actions carried out by the 16 male category and the 18 female category teams that participated in the Under-16 Spanish Championship. The dependent variable was setting efficacy. The independent variables were grouped into: serve variables (a serve zone, the type of serve, striking technique, an in-game role of the server and serve direction), reception variables (a reception zone, a receiver player and reception efficacy) and setting variables (a setter's position, a setting zone, the type of a set, setting technique, a set's area and tempo of a set). Multinomial logistic regression showed that the best predictive variables of setting efficacy, both in female and male categories, were reception efficacy, setting technique and tempo of a set. In the male category, the jump serve was the greatest predictor of setting efficacy, while in the female category, it was the set's area. Therefore, in the male category, it was not only the preceding action that affected setting efficacy, but also the serve. On the contrary, in the female category, only variables of the action itself and of the previous action, reception, affected setting efficacy. The results obtained in the present study should be taken into account in the training process of both male and female volleyball players in formative stages.

An attentional drift diffusion model over binary-attribute choice.

PubMed

Fisher, Geoffrey

2017-11-01

In order to make good decisions, individuals need to identify and properly integrate information about various attributes associated with a choice. Since choices are often complex and made rapidly, they are typically affected by contextual variables that are thought to influence how much attention is paid to different attributes. I propose a modification of the attentional drift-diffusion model, the binary-attribute attentional drift diffusion model (baDDM), which describes the choice process over simple binary-attribute choices and how it is affected by fluctuations in visual attention. Using an eye-tracking experiment, I find the baDDM makes accurate quantitative predictions about several key variables including choices, reaction times, and how these variables are correlated with attention to two attributes in an accept-reject decision. Furthermore, I estimate an attribute-based fixation bias that suggests attention to an attribute increases its subjective weight by 5%, while the unattended attribute's weight is decreased by 10%. Copyright © 2017 Elsevier B.V. All rights reserved.

Climate change hampers endangered species through intensified moisture-related plant stresses

NASA Astrophysics Data System (ADS)

(Ruud) Bartholomeus, R. P.; (Flip) Witte, J. P. M.; (Peter) van Bodegom, P. M.; (Jos) van Dam, J. C.; (Rien) Aerts, R.

2010-05-01

With recent climate change, extremes in meteorological conditions are forecast and observed to increase globally, and to affect vegetation composition. More prolonged dry periods will alternate with more intensive rainfall events, both within and between years, which will change soil moisture dynamics. In temperate climates, soil moisture, in concert with nutrient availability and soil acidity, is the most important environmental filter in determining local plant species composition, as it determines the availability of both oxygen and water to plant roots. These resources are indispensable for meeting the physiological demands of plants. The consequences of climate change for our natural environment are among the most pressing issues of our time. The international research community is beginning to realise that climate extremes may be more powerful drivers of vegetation change and species extinctions than slow-and-steady climatic changes, but the causal mechanisms of such changes are presently unknown. The roles of amplitudes in water availability as drivers of vegetation change have been particularly elusive owing to the lack of integration of the key variables involved. Here we show that the combined effect of increased rainfall variability, temperature and atmospheric CO2-concentration will lead to an increased variability in both wet and dry extremes in stresses faced by plants (oxygen and water stress, respectively). We simulated these plant stresses with a novel, process-based approach, incorporating in detail the interacting processes in the soil-plant-atmosphere interface. In order to quantify oxygen and water stress with causal measures, we focused on interacting meteorological, soil physical, microbial, and plant physiological processes in the soil-plant-atmosphere system. The first physiological process inhibited at high soil moisture contents is plant root respiration, i.e. oxygen consumption in the roots, which responds to increased temperatures. High soil moisture contents hamper oxygen transport from the atmosphere, through the soil - where part of the oxygen additionally disappears by soil microbial oxygen consumption - and to the root cells. Reduced respiration negatively affects the energy supply to plant metabolism. Plant transpiration, which responds to increased temperatures and atmospheric CO2-concentrations, is the first physiological process that will be inhibited by low soil moisture contents, negatively affecting both photosynthesis and cooling. As both the supply and demand of oxygen and water depend strongly on the prevailing meteorological conditions, both oxygen and water stress were calculated dynamically in time to capture climate change effects. We demonstrate that increased rainfall variability in interaction with predicted changes in temperature and CO2, affects soil moisture conditions and plant oxygen and water demands such, that both oxygen stress and water stress will intensify due to climate change. Moreover, these stresses will increasingly coincide, causing variable stress conditions. These variable stress conditions were found to decrease future habitat suitability, especially for plant species that are presently endangered. The future existence of such species is thus at risk by climate change, which has direct implications for policies to maintain endangered species, as applied by international nature management organisations (e.g. IUCN). Our integrated mechanistic analysis of two stresses combined, which has never been done so far, reveals large impacts of climate change on species extinctions and thereby on biodiversity.

Meta-analysis of variables affecting mouse protection efficacy of whole organism Brucella vaccines and vaccine candidates

PubMed Central

2013-01-01

Background Vaccine protection investigation includes three processes: vaccination, pathogen challenge, and vaccine protection efficacy assessment. Many variables can affect the results of vaccine protection. Brucella, a genus of facultative intracellular bacteria, is the etiologic agent of brucellosis in humans and multiple animal species. Extensive research has been conducted in developing effective live attenuated Brucella vaccines. We hypothesized that some variables play a more important role than others in determining vaccine protective efficacy. Using Brucella vaccines and vaccine candidates as study models, this hypothesis was tested by meta-analysis of Brucella vaccine studies reported in the literature. Results Nineteen variables related to vaccine-induced protection of mice against infection with virulent brucellae were selected based on modeling investigation of the vaccine protection processes. The variable "vaccine protection efficacy" was set as a dependent variable while the other eighteen were set as independent variables. Discrete or continuous values were collected from papers for each variable of each data set. In total, 401 experimental groups were manually annotated from 74 peer-reviewed publications containing mouse protection data for live attenuated Brucella vaccines or vaccine candidates. Our ANOVA analysis indicated that nine variables contributed significantly (P-value < 0.05) to Brucella vaccine protection efficacy: vaccine strain, vaccination host (mouse) strain, vaccination dose, vaccination route, challenge pathogen strain, challenge route, challenge-killing interval, colony forming units (CFUs) in mouse spleen, and CFU reduction compared to control group. The other 10 variables (e.g., mouse age, vaccination-challenge interval, and challenge dose) were not found to be statistically significant (P-value > 0.05). The protection level of RB51 was sacrificed when the values of several variables (e.g., vaccination route, vaccine viability, and challenge pathogen strain) change. It is suggestive that it is difficult to protect against aerosol challenge. Somewhat counter-intuitively, our results indicate that intraperitoneal and subcutaneous vaccinations are much more effective to protect against aerosol Brucella challenge than intranasal vaccination. Conclusions Literature meta-analysis identified variables that significantly contribute to Brucella vaccine protection efficacy. The results obtained provide critical information for rational vaccine study design. Literature meta-analysis is generic and can be applied to analyze variables critical for vaccine protection against other infectious diseases. PMID:23735014

How are streamflow responses to the El Nino Southern Oscillation affected by watershed characteristics?

NASA Astrophysics Data System (ADS)

Rice, Joshua S.; Emanuel, Ryan E.

2017-05-01

Understanding the factors that influence how global climate phenomena, such as the El-Nino Southern Oscillation (ENSO), affect streamflow behavior is an important area of research in the hydrologic sciences. While large-scale patterns in ENSO-streamflow relationships have been thoroughly studied, and are relatively well-understood, information is scarce concerning factors that affect variation in ENSO responses from one watershed to another. To this end, we examined relationships between variability in ENSO activity and streamflow for 2731 watersheds across the conterminous U.S. from 1970 to 2014 using a novel approach to account for the intermediary role of precipitation. We applied an ensemble of regression techniques to describe relationships between variability in ENSO activity and streamflow as a function of watershed characteristics including: hydroclimate, topography, geomorphology, geographic location, land cover, soil characteristics, bedrock geology, and anthropogenic influences. We found that variability in watershed scale ENSO-streamflow relationships was strongly related to factors including: precipitation timing and phase, forest cover, and interactions between watershed topography and geomorphology. These, and other influential factors, share in common the ability to affect the partitioning and movement of water within watersheds. Our results demonstrate that the conceptualization of watersheds as signal filters for hydroclimate inputs, commonly applied to short-term rainfall-runoff responses, also applies to long-term hydrologic responses to sources of recurrent climate variability. These results also show that watershed processes, which are typically studied at relatively fine spatial scales, are also critical for understanding continental scale hydrologic responses to global climate.

Bioreactor process parameter screening utilizing a Plackett-Burman design for a model monoclonal antibody.

PubMed

Agarabi, Cyrus D; Schiel, John E; Lute, Scott C; Chavez, Brittany K; Boyne, Michael T; Brorson, Kurt A; Khan, Mansoora; Read, Erik K

2015-06-01

Consistent high-quality antibody yield is a key goal for cell culture bioprocessing. This endpoint is typically achieved in commercial settings through product and process engineering of bioreactor parameters during development. When the process is complex and not optimized, small changes in composition and control may yield a finished product of less desirable quality. Therefore, changes proposed to currently validated processes usually require justification and are reported to the US FDA for approval. Recently, design-of-experiments-based approaches have been explored to rapidly and efficiently achieve this goal of optimized yield with a better understanding of product and process variables that affect a product's critical quality attributes. Here, we present a laboratory-scale model culture where we apply a Plackett-Burman screening design to parallel cultures to study the main effects of 11 process variables. This exercise allowed us to determine the relative importance of these variables and identify the most important factors to be further optimized in order to control both desirable and undesirable glycan profiles. We found engineering changes relating to culture temperature and nonessential amino acid supplementation significantly impacted glycan profiles associated with fucosylation, β-galactosylation, and sialylation. All of these are important for monoclonal antibody product quality. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

Combined effects of positive and negative affectivity and job satisfaction on job performance and turnover intentions.

PubMed

Bouckenooghe, Dave; Raja, Usman; Butt, Arif Nazir

2013-01-01

Capturing data from employee-supervisor dyads (N = 321) from eight organizations in Pakistan, including human service organizations, an electronics assembly plant, a packaging material manufacturing company, and a small food processing plant, we used moderated regression analysis to examine whether the relationships between trait affect (positive affectivity [PA] and negative affectivity [NA]) and two key work outcome variables (job performance and turnover) are contingent upon the level of job satisfaction. We applied the Trait Activation Theory to explain the moderating effect of job satisfaction on the relationship between affect and performance and between affect and turnover. Overall, the data supported our hypotheses. Positive and negative affectivity influenced performance and the intention to quit, and job satisfaction moderated these relationships. We discuss in detail the results of these findings and their implications for research and practice.

Drivers of inter-year variability of plant production and decomposers across contrasting island ecosystems.

PubMed

Wardle, David A; Jonsson, Micael; Kalela-Brundin, Maarit; Lagerström, Anna; Bardgett, Richard D; Yeates, Gregor W; Nilsson, Marie-Charlotte

2012-03-01

Despite the likely importance of inter-year dynamics of plant production and consumer biota for driving community- and ecosystem-level processes, very few studies have explored how and why these dynamics vary across contrasting ecosystems. We utilized a well-characterized system of 30 lake islands in the boreal forest zone of northern Sweden across which soil fertility and productivity vary considerably, with larger islands being more fertile and productive than smaller ones. In this system we assessed the inter-year dynamics of several measures of plant production and the soil microbial community (primary consumers in the decomposer food web) for each of nine years, and soil microfaunal groups (secondary and tertiary consumers) for each of six of those years. We found that, for measures of plant production and each of the three consumer trophic levels, inter-year dynamics were strongly affected by island size. Further, many variables were strongly affected by island size (and thus bottom-up regulation by soil fertility and resources) in some years, but not in other years, most likely due to inter-year variation in climatic conditions. For each of the plant and microbial variables for which we had nine years of data, we also determined the inter-year coefficient of variation (CV), an inverse measure of stability. We found that CVs of some measures of plant productivity were greater on large islands, whereas those of other measures were greater on smaller islands; CVs of microbial variables were unresponsive to island size. We also found that the effects of island size on the temporal dynamics of some variables were related to inter-year variability of macroclimatic variables. As such, our results show that the inter-year dynamics of both plant productivity and decomposer biota across each of three trophic levels, as well as the inter-year stability of plant productivity, differ greatly across contrasting ecosystems, with potentially important but largely overlooked implications for community and ecosystem processes.

An investigative model evaluating how consumers process pictorial information on nonprescription medication labels.

PubMed

Sansgiry, S S; Cady, P S

1997-01-01

Currently, marketed over-the-counter (OTC) medication labels were simulated and tested in a controlled environment to understand consumer evaluation of OTC label information. Two factors, consumers' age (younger and older adults) and label designs (picture-only, verbal-only, congruent picture-verbal, and noncongruent picture-verbal) were controlled and tested to evaluate consumer information processing. The effects exerted by the independent variables, namely, comprehension of label information (understanding) and product evaluations (satisfaction, certainty, and perceived confusion) were evaluated on the dependent variable purchase intention. Intention measured as purchase recommendation was significantly related to product evaluations and affected by the factor label design. Participants' level of perceived confusion was more important than actual understanding of information on OTC medication labels. A Label Evaluation Process Model was developed which could be used for future testing of OTC medication labels.

Does prior psychotherapy experience affect the course of cognitive-behavioural group therapy for social anxiety disorder?

PubMed

Delsignore, Aba

2008-08-01

To examine whether and how different patterns of psychotherapy history (no prior therapy, successful therapy experience, and unsuccessful therapy experience) affect the outcome of future treatment among patients undergoing cognitive-behavioural group therapy for social anxiety disorder. Fifty-seven patients with varying histories of psychotherapy participating in cognitive-behavioural group treatment for social anxiety disorder were included in the study. Symptom severity (including anxiety, depression, self-efficacy, and global symptom severity) was assessed at pre- and posttreatment. A therapist-rated measure of patient therapy engagement was included as a process variable. First-time therapy patients showed more favourable pretreatment variables and achieved greater benefit from group therapy. Among patients with unsuccessful therapy experience, substantial gains were attained by those who were able to actively engage in the therapy process. Patients rating previous therapies as successful could benefit the least and tended to stagnate. Possible explanations for group differences and clinical implications are discussed. Prior psychotherapy experience affects the course of cognitive-behavioural group therapy in patients with social phobias. While patients with negative therapy experience may need extensive support in being and remaining actively engaged, those rating previous therapies as successful should be assessed very carefully and may benefit from a major focus on relational aspects.

Linking daily stress processes and laboratory-based heart rate variability in a national sample of midlife and older adults

PubMed Central

Sin, Nancy L.; Sloan, Richard P.; McKinley, Paula S.; Almeida, David M.

2015-01-01

Objective This study evaluates the associations between people’s trait-like patterns of stress in daily life (stressor frequency, perceived stressor severity, affective reactivity to stressors, and negative affect) and laboratory-assessed heart rate variability (HRV). Methods Data were collected from 909 participants ages 35-85 in the Midlife in the United States Study. Participants reported negative affect and minor stressful events during telephone interviews on eight consecutive evenings. On a separate occasion, HRV was measured from electrocardiograph recordings taken at rest during a laboratory-based psychophysiology protocol. Regression models were used to evaluate the associations between daily stress processes and 3 log-transformed HRV indices: standard deviation of RR intervals (SDRR), root mean square of successive differences (RMSSD), and high-frequency power (HF-HRV). Analyses were adjusted for demographics, body mass index, comorbid conditions, medications, physical activity, and smoking. Results Stressor frequency was unrelated to HRV (r-values ranging from −0.04 to −0.01, p’s > 0.20). However, people with greater perceived stressor severity had lower resting SDRR (fully-adjusted B [SE] = −0.05 [0.02]), RMSSD (−0.08 [0.03]), and HF-HRV (−0.16 [0.07]). Individuals with more pronounced affective reactivity to stressors also had lower levels of all 3 HRV indices (SDRR: B [SE] = −0.28 [0.14]; RMSSD: −0.44 [0.19]; HF-HRV: −0.96 [0.37]). Furthermore, aggregated daily negative affect was linked to reduced RMSSD (B [SE] = −0.16 [0.08]) and HF-HRV (−0.35 [0.15]). Conclusions In a national sample, individual differences in daily negative affect and responses to daily stressors were more strongly related to cardiovascular autonomic regulation than the frequency of such stressors. PMID:26867082

Affective neuroscience of self-generated thought.

PubMed

Fox, Kieran C R; Andrews-Hanna, Jessica R; Mills, Caitlin; Dixon, Matthew L; Markovic, Jelena; Thompson, Evan; Christoff, Kalina

2018-05-12

Despite increasing scientific interest in self-generated thought-mental content largely independent of the immediate environment-there has yet to be any comprehensive synthesis of the subjective experience and neural correlates of affect in these forms of thinking. Here, we aim to develop an integrated affective neuroscience encompassing many forms of self-generated thought-normal and pathological, moderate and excessive, in waking and in sleep. In synthesizing existing literature on this topic, we reveal consistent findings pertaining to the prevalence, valence, and variability of emotion in self-generated thought, and highlight how these factors might interact with self-generated thought to influence general well-being. We integrate these psychological findings with recent neuroimaging research, bringing attention to the neural correlates of affect in self-generated thought. We show that affect in self-generated thought is prevalent, positively biased, highly variable (both within and across individuals), and consistently recruits many brain areas implicated in emotional processing, including the orbitofrontal cortex, amygdala, insula, and medial prefrontal cortex. Many factors modulate these typical psychological and neural patterns, however; the emerging affective neuroscience of self-generated thought must endeavor to link brain function and subjective experience in both everyday self-generated thought as well as its dysfunctions in mental illness. © 2018 New York Academy of Sciences.

A UV-to-MIR monitoring of DR Tau: Exploring how water vapor in the planet formation region is affected by stellar accretion variability

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

Banzatti, A.; Meyer, M. R.; Manara, C. F.

2014-01-01

Young stars are known to show variability due to non-steady mass accretion rate from their circumstellar disks. Accretion flares can produce strong energetic irradiation and heating that may affect the disk in the planet formation region, close to the central star. During an extreme accretion outburst in the young star EX Lupi, the prototype of EXor variables, remarkable changes in molecular gas emission from ∼1 AU in the disk have recently been observed. Here, we focus on water vapor and explore how it is affected by variable accretion luminosity in T Tauri stars. We monitored a young highly variable solar-massmore » star, DR Tau, using simultaneously two high/medium-resolution spectrographs at the European Southern Observatory Very Large Telescope: VISIR at 12.4 μm to observe water lines from the disk and X-shooter covering from 0.3 to 2.5 μm to constrain the stellar accretion. Three epochs spanning timescales from several days to several weeks were obtained. The accretion luminosity was estimated to change within a factor of ∼2 and no change in water emission was detected at a significant level. In comparison with EX Lupi and EXor outbursts, DR Tau suggests that the less long-lived and weaker variability phenomena typical of T Tauri stars may leave water at planet-forming radii in the disk mostly unaffected. We propose that these systems may provide evidence for two processes that act over different timescales: ultraviolet photochemistry in the disk atmosphere (faster) and heating of the deeper disk layers (slower).« less

Dual process interaction model of HIV-risk behaviors among drug offenders.

PubMed

Ames, Susan L; Grenard, Jerry L; Stacy, Alan W

2013-03-01

This study evaluated dual process interaction models of HIV-risk behavior among drug offenders. A dual process approach suggests that decisions to engage in appetitive behaviors result from a dynamic interplay between a relatively automatic associative system and an executive control system. One synergistic type of interplay suggests that executive functions may dampen or block effects of spontaneously activated associations. Consistent with this model, latent variable interaction analyses revealed that drug offenders scoring higher in affective decision making were relatively protected from predictive effects of spontaneous sex associations promoting risky sex. Among drug offenders with lower levels of affective decision making ability, spontaneous sexually-related associations more strongly predicted risky sex (lack of condom use and greater number of sex partners). These findings help elucidate associative and control process effects on appetitive behaviors and are important for explaining why some individuals engage in risky sex, while others are relatively protected.

Dual Process Interaction Model of HIV-Risk Behaviors Among Drug Offenders

PubMed Central

Grenard, Jerry L.; Stacy, Alan W.

2012-01-01

This study evaluated dual process interaction models of HIV-risk behavior among drug offenders. A dual process approach suggests that decisions to engage in appetitive behaviors result from a dynamic interplay between a relatively automatic associative system and an executive control system. One synergistic type of interplay suggests that executive functions may dampen or block effects of spontaneously activated associations. Consistent with this model, latent variable interaction analyses revealed that drug offenders scoring higher in affective decision making were relatively protected from predictive effects of spontaneous sex associations promoting risky sex. Among drug offenders with lower levels of affective decision making ability, spontaneous sexually-related associations more strongly predicted risky sex (lack of condom use and greater number of sex partners). These findings help elucidate associative and control process effects on appetitive behaviors and are important for explaining why some individuals engage in risky sex, while others are relatively protected. PMID:22331391

The role of musical training in emergent and event-based timing.

PubMed

Baer, L H; Thibodeau, J L N; Gralnick, T M; Li, K Z H; Penhune, V B

2013-01-01

Musical performance is thought to rely predominantly on event-based timing involving a clock-like neural process and an explicit internal representation of the time interval. Some aspects of musical performance may rely on emergent timing, which is established through the optimization of movement kinematics, and can be maintained without reference to any explicit representation of the time interval. We predicted that musical training would have its largest effect on event-based timing, supporting the dissociability of these timing processes and the dominance of event-based timing in musical performance. We compared 22 musicians and 17 non-musicians on the prototypical event-based timing task of finger tapping and on the typically emergently timed task of circle drawing. For each task, participants first responded in synchrony with a metronome (Paced) and then responded at the same rate without the metronome (Unpaced). Analyses of the Unpaced phase revealed that non-musicians were more variable in their inter-response intervals for finger tapping compared to circle drawing. Musicians did not differ between the two tasks. Between groups, non-musicians were more variable than musicians for tapping but not for drawing. We were able to show that the differences were due to less timer variability in musicians on the tapping task. Correlational analyses of movement jerk and inter-response interval variability revealed a negative association for tapping and a positive association for drawing in non-musicians only. These results suggest that musical training affects temporal variability in tapping but not drawing. Additionally, musicians and non-musicians may be employing different movement strategies to maintain accurate timing in the two tasks. These findings add to our understanding of how musical training affects timing and support the dissociability of event-based and emergent timing modes.

The Mediating Role of Affective Commitment in the Relation of the Feedback Environment to Work Outcomes

ERIC Educational Resources Information Center

Norris-Watts, Christina; Levy, Paul E.

2004-01-01

The Feedback Environment, as opposed to the formal performance appraisal process, is comprised of the daily interactions between members of an organization (Steelman, Levy, & Snell, in press). Relations between the feedback environment and work outcome variables such as Organizational Citizenship Behavior (OCB) were examined through the mediating…

The role of time in place attachment

Treesearch

David Smaldone

2007-01-01

Quantitative studies have found that the length of association is an important variable affecting place attachment (Kaltenborn 1998, Moore & Graefe 1994, Patterson & Williams 1991, Vorkinn & Riese 2001). These studies, however, have provided less insight into how and why time is involved in the process of forming place attachment, as well as the meanings...

A neutral model of low-severity fire regimes

Treesearch

Don McKenzie; Amy E. Hessl

2008-01-01

Climate, topography, fuel loadings, and human activities all affect spatial and temporal patterns of fire occurrence. Because fire occurrence is a stochastic process, an understanding of baseline variability is necessary in order to identify constraints on surface fire regimes. With a suitable null, or neutral, model, characteristics of natural fire regimes estimated...

Exploring the "Lone Wolf" Phenomenon in Student Teams

ERIC Educational Resources Information Center

Barr, Terri Feldman; Dixon, Andrea L.; Gassenheimer, Jule B.

2005-01-01

The proliferation of projects using student teams has motivated researchers to examine factors that affect both team process and outcomes. This research introduces an individual difference variable found in the business environment that has not been examined in a classroom context. The lone wolf appears to play a role in how teams function and…

Processes Affecting the Variability of Fluorescence Signals from Benthic Targets in Shallow Waters

DTIC Science & Technology

2001-09-30

symbiotic corals. - Limnol. and Oceanogr., 46: 75-85. Gorbunov M.Y. and Falkowski P.G. 2001. Photoreceptors in the cnidarian hosts allow symbiotic...Gorbunov M.Y. and Falkowski P.G. 2001. Photoreceptors in the cnidarian hosts allow symbiotic corals to sense blue moonlight. – Limnol. and Oceanogr

Ecosystem dynamics and disturbance in mountain wildernesses: assessing vulnerability of natural resources to change

Treesearch

Daniel B. Fagre; David L. Peterson

2000-01-01

An integrated program of ecosystem modeling and extensive field studies at Glacier and Olympic National Parks has quantified many of the ecological processes affected by climatic variability and disturbance. Models have successfully estimated snow distribution, annual watershed discharge, and stream temperature variation based on seven years of monitoring. Various...

Winter climate change affects growing-season soil microbial biomass and activity in northern hardwood forests.

PubMed

Durán, Jorge; Morse, Jennifer L; Groffman, Peter M; Campbell, John L; Christenson, Lynn M; Driscoll, Charles T; Fahey, Timothy J; Fisk, Melany C; Mitchell, Myron J; Templer, Pamela H

2014-11-01

Understanding the responses of terrestrial ecosystems to global change remains a major challenge of ecological research. We exploited a natural elevation gradient in a northern hardwood forest to determine how reductions in snow accumulation, expected with climate change, directly affect dynamics of soil winter frost, and indirectly soil microbial biomass and activity during the growing season. Soils from lower elevation plots, which accumulated less snow and experienced more soil temperature variability during the winter (and likely more freeze/thaw events), had less extractable inorganic nitrogen (N), lower rates of microbial N production via potential net N mineralization and nitrification, and higher potential microbial respiration during the growing season. Potential nitrate production rates during the growing season were particularly sensitive to changes in winter snow pack accumulation and winter soil temperature variability, especially in spring. Effects of elevation and winter conditions on N transformation rates differed from those on potential microbial respiration, suggesting that N-related processes might respond differently to winter climate change in northern hardwood forests than C-related processes. © 2014 John Wiley & Sons Ltd.

Variability of mass-wasting processes in the tectonically-controlled Calabro Tyrrhenian continental margin (Southern Italy)

NASA Astrophysics Data System (ADS)

Casalbore, D.; Bosman, A.; Casas, D.; Chiocci, F. L.; Martorelli, E.; Ridente, D.

2017-12-01

The recent collection of multibeam bathymetry and single-channel seismic profiles on the Calabro-Tyrrhenian continental margin in Southern Italy allowed us to depict a large suite of mass-wasting processes, ranging from gullies up to shelf-indenting canyon system along with over 400 landslide scars, affecting the 52% of the entire area. In detail, slide scars occur from the coast down to -1700 m, with mobilized volumes ranging from some hundreds of m3 up to tens of millions of m3. On the whole, they affect an area of >85 km2, being able to mobilize approximately 1.4 km3. These slides also show a large variability of features both in the headwall, translational and toe domain, thus providing useful insights for a better understanding of their failure and post-failure behavior. The aim of this study is to show the magnitude-frequency relationship of this large amount of slides in order to quantify a range of probabilities for the occurrence of new landslide events as well as to illustrate the main mechanisms that control their development and emplacement.

Century-scale Changes in Environmental Synchrony and Variability and their Effects on Populations of Birds and Reproduction of Trees

NASA Astrophysics Data System (ADS)

Koenig, W.

2016-12-01

The ecological impacts of modern global climate change are detectable in a wide variety of phenomena ranging from shifts in species ranges to changes in community composition and human disease dynamics. Thus far, however, little attention has been given to temporal changes in environmental spatial synchrony-the coincident change in abundance or value across the landscape-or environmental variability, despite the importance of these factors as drivers of population rescue and extinction and reproductive dynamics of both animal and plant populations. We quantified spatial synchrony of widespread North American wintering birds species using Audubon Christmas Bird Counts over the past 50 years and seed set variability (mast fruiting) among trees over the past century and found that both spatial synchrony of the birds and seed set variability have significantly increased over these time periods. The first of these results was mirrored by significant increases in spatial synchrony of mean maximum air temperature across North America, primarily during the summer, while the second is consistent with the hypothesis that climate change is resulting in greater seed set variability. These findings suggest the potential for temporal changes in envioronmental synchrony and variability to be affecting a wide range of ecological phenomena by influencing the probability of population rescue and extinction and by affecting ecosystem processes that rely on the resource pulses provided by mast fruiting plants.

SLEEP AND MENTAL DISORDERS: A META-ANALYSIS OF POLYSOMNOGRAPHIC RESEARCH

PubMed Central

Baglioni, Chiara; Nanovska, Svetoslava; Regen, Wolfram; Spiegelhalder, Kai; Feige, Bernd; Nissen, Christoph; Reynolds, Charles F.; Riemann, Dieter

2016-01-01

Investigating sleep in mental disorders has the potential to reveal both disorder-specific and transdiagnostic psychophysiological mechanisms. This meta-analysis aimed at determining the polysomnographic (PSG) characteristics of several mental disorders. Relevant studies were searched through standard strategies. Controlled PSG studies evaluating sleep in affective, anxiety, eating, pervasive developmental, borderline and antisocial personality disorders, ADHD, and schizophrenia were included. PSG variables of sleep continuity, depth, and architecture, as well as rapid-eye movement (REM) sleep were considered. Calculations were performed with the “Comprehensive Meta-Analysis” and “R” softwares. Using random effects modeling, for each disorder and each variable, a separate meta-analysis was conducted if at least 3 studies were available for calculation of effect sizes as standardized means (Hedges’g). Sources of variability, i.e., sex, age, and mental disorders comorbidity, were evaluated in subgroup analyses. Sleep alterations were evidenced in all disorders, with the exception of ADHD and seasonal affective disorders. Sleep continuity problems were observed in most mental disorders. Sleep depth and REM pressure alterations were associated with affective, anxiety, autism and schizophrenia disorders. Comorbidity was associated with enhanced REM sleep pressure and more inhibition of sleep depth. No sleep parameter was exclusively altered in one condition; however, no two conditions shared the same PSG profile. Sleep continuity disturbances imply a transdiagnostic imbalance in the arousal system likely representing a basic dimension of mental health. Sleep depth and REM variables might play a key role in psychiatric comorbidity processes. Constellations of sleep alterations may define distinct disorders better than alterations in one single variable. PMID:27416139

Quality by design approach for understanding the critical quality attributes of cyclosporine ophthalmic emulsion.

PubMed

Rahman, Ziyaur; Xu, Xiaoming; Katragadda, Usha; Krishnaiah, Yellela S R; Yu, Lawrence; Khan, Mansoor A

2014-03-03

Restasis is an ophthalmic cyclosporine emulsion used for the treatment of dry eye syndrome. There are no generic products for this product, probably because of the limitations on establishing in vivo bioequivalence methods and lack of alternative in vitro bioequivalence testing methods. The present investigation was carried out to understand and identify the appropriate in vitro methods that can discriminate the effect of formulation and process variables on critical quality attributes (CQA) of cyclosporine microemulsion formulations having the same qualitative (Q1) and quantitative (Q2) composition as that of Restasis. Quality by design (QbD) approach was used to understand the effect of formulation and process variables on critical quality attributes (CQA) of cyclosporine microemulsion. The formulation variables chosen were mixing order method, phase volume ratio, and pH adjustment method, while the process variables were temperature of primary and raw emulsion formation, microfluidizer pressure, and number of pressure cycles. The responses selected were particle size, turbidity, zeta potential, viscosity, osmolality, surface tension, contact angle, pH, and drug diffusion. The selected independent variables showed statistically significant (p < 0.05) effect on droplet size, zeta potential, viscosity, turbidity, and osmolality. However, the surface tension, contact angle, pH, and drug diffusion were not significantly affected by independent variables. In summary, in vitro methods can detect formulation and manufacturing changes and would thus be important for quality control or sameness of cyclosporine ophthalmic products.

Microbial production of polyhydroxybutyrate with tailor-made properties: an integrated modelling approach and experimental validation.

PubMed

Penloglou, Giannis; Chatzidoukas, Christos; Kiparissides, Costas

2012-01-01

The microbial production of polyhydroxybutyrate (PHB) is a complex process in which the final quantity and quality of the PHB depend on a large number of process operating variables. Consequently, the design and optimal dynamic operation of a microbial process for the efficient production of PHB with tailor-made molecular properties is an extremely interesting problem. The present study investigates how key process operating variables (i.e., nutritional and aeration conditions) affect the biomass production rate and the PHB accumulation in the cells and its associated molecular weight distribution. A combined metabolic/polymerization/macroscopic modelling approach, relating the process performance and product quality with the process variables, was developed and validated using an extensive series of experiments and measurements. The model predicts the dynamic evolution of the biomass growth, the polymer accumulation, the consumption of carbon and nitrogen sources and the average molecular weights of the PHB in a bioreactor, under batch and fed-batch operating conditions. The proposed integrated model was used for the model-based optimization of the production of PHB with tailor-made molecular properties in Azohydromonas lata bacteria. The process optimization led to a high intracellular PHB accumulation (up to 95% g of PHB per g of DCW) and the production of different grades (i.e., different molecular weight distributions) of PHB. Copyright © 2011 Elsevier Inc. All rights reserved.

Micro-topographic hydrologic variability due to vegetation acclimation under climate change

NASA Astrophysics Data System (ADS)

Le, P. V.; Kumar, P.

2012-12-01

Land surface micro-topography and vegetation cover have fundamental effects on the land-atmosphere interactions. The altered temperature and precipitation variability associated with climate change will affect the water and energy processes both directly and that mediated through vegetation. Since climate change induces vegetation acclimation that leads to shifts in evapotranspiration and heat fluxes, it further modifies microclimate and near-surface hydrological processes. In this study, we investigate the impacts of vegetation acclimation to climate change on micro-topographic hydrologic variability. The ability to accurately predict these impacts requires the simultaneous considerations of biochemical, ecophysiological and hydrological processes. A multilayer canopy-root-soil system model coupled with a conjunctive surface-subsurface flow model is used to capture the acclimatory responses and analyze the changes in dynamics of structure and connectivity of micro-topographic storage and in magnitudes of runoff. The study is performed using Light Detection and Ranging (LiDAR) topographic data in the Birds Point-New Madrid floodway in Missouri, U.S.A. The result indicates that both climate change and its associated vegetation acclimation play critical roles in altering the micro-topographic hydrological responses.

Human footprint affects US carbon balance more than climate change

USGS Publications Warehouse

Bachelet, Dominique; Ferschweiler, Ken; Sheehan, Tim; Baker, Barry; Sleeter, Benjamin M.; Zhu, Zhiliang

2017-01-01

The MC2 model projects an overall increase in carbon capture in conterminous United States during the 21st century while also simulating a rise in fire causing much carbon loss. Carbon sequestration in soils is critical to prevent carbon losses from future disturbances, and we show that natural ecosystems store more carbon belowground than managed systems do. Natural and human-caused disturbances affect soil processes that shape ecosystem recovery and competitive interactions between native, exotics, and climate refugees. Tomorrow's carbon budgets will depend on how land use, natural disturbances, and climate variability will interact and affect the balance between carbon capture and release.

Pluck or Luck: Does Trait Variation or Chance Drive Variation in Lifetime Reproductive Success?

PubMed

Snyder, Robin E; Ellner, Stephen P

2018-04-01

While there has been extensive interest in how intraspecific trait variation affects ecological processes, outcomes are highly variable even when individuals are identical: some are lucky, while others are not. Trait variation is therefore important only if it adds substantially to the variability produced by luck. We ask when trait variation has a substantial effect on variability in lifetime reproductive success (LRS), using two approaches: (1) we partition the variation in LRS into contributions from luck and trait variation and (2) we ask what can be inferred about an individual's traits and with what certainty, given their observed LRS. In theoretical stage- and size-structured models and two empirical case studies, we find that luck usually dominates the variance of LRS. Even when individuals differ substantially in ways that affect expected LRS, unless the effects of luck are substantially reduced (e.g., low variability in reproductive life span or annual fecundity), most variance in lifetime outcomes is due to luck, implying that departures from "null" models omitting trait variation will be hard to detect. Luck also obscures the relationship between realized LRS and individual traits. While trait variation may influence the fate of populations, luck often governs the lives of individuals.

Motor-sensory confluence in tactile perception.

PubMed

Saig, Avraham; Gordon, Goren; Assa, Eldad; Arieli, Amos; Ahissar, Ehud

2012-10-03

Perception involves motor control of sensory organs. However, the dynamics underlying emergence of perception from motor-sensory interactions are not yet known. Two extreme possibilities are as follows: (1) motor and sensory signals interact within an open-loop scheme in which motor signals determine sensory sampling but are not affected by sensory processing and (2) motor and sensory signals are affected by each other within a closed-loop scheme. We studied the scheme of motor-sensory interactions in humans using a novel object localization task that enabled monitoring the relevant overt motor and sensory variables. We found that motor variables were dynamically controlled within each perceptual trial, such that they gradually converged to steady values. Training on this task resulted in improvement in perceptual acuity, which was achieved solely by changes in motor variables, without any change in the acuity of sensory readout. The within-trial dynamics is captured by a hierarchical closed-loop model in which lower loops actively maintain constant sensory coding, and higher loops maintain constant sensory update flow. These findings demonstrate interchangeability of motor and sensory variables in perception, motor convergence during perception, and a consistent hierarchical closed-loop perceptual model.

Cognitive determinants of affective forecasting errors

PubMed Central

Hoerger, Michael; Quirk, Stuart W.; Lucas, Richard E.; Carr, Thomas H.

2011-01-01

Often to the detriment of human decision making, people are prone to an impact bias when making affective forecasts, overestimating the emotional consequences of future events. The cognitive processes underlying the impact bias, and methods for correcting it, have been debated and warrant further exploration. In the present investigation, we examined both individual differences and contextual variables associated with cognitive processing in affective forecasting for an election. Results showed that the perceived importance of the event and working memory capacity were both associated with an increased impact bias for some participants, whereas retrieval interference had no relationship with bias. Additionally, an experimental manipulation effectively reduced biased forecasts, particularly among participants who were most distracted thinking about peripheral life events. These findings have direct theoretical implications for understanding the impact bias, highlight the importance of individual differences in affective forecasting, and have ramifications for future decision making research. The possible functional role of the impact bias is discussed within the context of evolutionary psychology. PMID:21912580

Factors affecting strategic plan implementation using interpretive structural modeling (ISM).

PubMed

Bahadori, Mohammadkarim; Teymourzadeh, Ehsan; Tajik, Hamidreza; Ravangard, Ramin; Raadabadi, Mehdi; Hosseini, Seyed Mojtaba

2018-06-11

Purpose Strategic planning is the best tool for managers seeking an informed presence and participation in the market without surrendering to changes. Strategic planning enables managers to achieve their organizational goals and objectives. Hospital goals, such as improving service quality and increasing patient satisfaction cannot be achieved if agreed strategies are not implemented. The purpose of this paper is to investigate the factors affecting strategic plan implementation in one teaching hospital using interpretive structural modeling (ISM). Design/methodology/approach The authors used a descriptive study involving experts and senior managers; 16 were selected as the study sample using a purposive sampling method. Data were collected using a questionnaire designed and prepared based on previous studies. Data were analyzed using ISM. Findings Five main factors affected strategic plan implementation. Although all five variables and factors are top level, "senior manager awareness and participation in the strategic planning process" and "creating and maintaining team participation in the strategic planning process" had maximum drive power. "Organizational structure effects on the strategic planning process" and "Organizational culture effects on the strategic planning process" had maximum dependence power. Practical implications Identifying factors affecting strategic plan implementation is a basis for healthcare quality improvement by analyzing the relationship among factors and overcoming the barriers. Originality/value The authors used ISM to analyze the relationship between factors affecting strategic plan implementation.

Adult Demography and Larval Processes in Coastal Benthic Populations: Intertidal Barnacles in Southern California and Baja California

DTIC Science & Technology

2005-09-01

mechanism for near-shore concentration and estuarine recruitment of post-larval Penaeus plebejus Hess ( Decapoda , Penaeidae). Estuarine, Coastal and...the physical The dynamics of coastal populations is highly processes that are likely to affect the distribution dependent on the mechanisms and...help. I was lucky to land on a lab where, depending on the lunar phase, time of year, and who knows what other environmental variables, I would find a

Job satisfaction among mental healthcare professionals: The respective contributions of professional characteristics, team attributes, team processes, and team emergent states

PubMed Central

Fleury, Marie-Josée; Grenier, Guy; Bamvita, Jean-Marie

2017-01-01

Objectives: The aim of this study was to determine the respective contribution of professional characteristics, team attributes, team processes, and team emergent states on the job satisfaction of 315 mental health professionals from Quebec (Canada). Methods: Job satisfaction was measured with the Job Satisfaction Survey. Independent variables were organized into four categories according to a conceptual framework inspired from the Input-Mediator-Outcomes-Input Model. The contribution of each category of variables was assessed using hierarchical regression analysis. Results: Variations in job satisfaction were mostly explained by team processes, with minimal contribution from the other three categories. Among the six variables significantly associated with job satisfaction in the final model, four were team processes: stronger team support, less team conflict, deeper involvement in the decision-making process, and more team collaboration. Job satisfaction was also associated with nursing and, marginally, male gender (professional characteristics) as well as with a stronger affective commitment toward the team (team emergent states). Discussion and Conclusion: Results confirm the importance for health managers of offering adequate support to mental health professionals, and creating an environment favorable to collaboration and decision-sharing, and likely to reduce conflicts between team members. PMID:29276591

Effect of feed moisture, extrusion temperature and screw speed on properties of soy white flakes based aquafeed: a response surface analysis.

PubMed

Singh, Sushil K; Muthukumarappan, Kasiviswanathan

2016-04-01

Soy white flakes (SWF) is an intermediate product during soy bean processing. It is an untoasted inexpensive product and contains around 51% of crude protein. It can be a potential source of protein to replace fish meal for developing aquafeed. The extrusion process is versatile and is used for the development of aquafeed. Our objective was to study the effects of inclusion of SWF (up to 50%) and other extrusion processing parameters such as barrel temperature and screw speed on the properties of aquafeed extrudates using a single-screw extruder. Extrudate properties, including pellet durability index, bulk density, water absorption and solubility indices and mass flow rate, were significantly (P < 0.05) affected by the process variables. SWF was the most significant variable with quadratic effects on most of the properties. Increasing temperature and screw speed resulted in increase in durability and mass flow rate of extrudates. Response surface regression models were established to correlate the properties of extrudates to the process variables. SWF was used as an alternative protein source of fish meal. Our study shows that aquafeed with high durability, lower bulk density and lower water absorption and higher solubility indices can be obtained by adding SWF up to 40%. © 2015 Society of Chemical Industry.

Factors Affecting Husband Participation in Antenatal Care Attendance and Delivery

NASA Astrophysics Data System (ADS)

Rumaseuw, R.; Berliana, S. M.; Nursalam, N.; Efendi, F.; Pradanie, R.; Rachmawati, P. D.; Aurizki, G. E.

2018-02-01

The government has implemented several programs to prevent and reduce a mother’s mortality rate by enhancing active role of the family. The most responsible family member on maintaining the pregnancy and delivery process is the husband. The husband must be active to take care of his wife. Active participation of the husband in accompanying his wife during pregnancy and the delivery process is one of the substantial factors, which helps the husband to take decisions related to the health of his wife. This study aimed to identify variables and its trends, which significantly affect a husband’s participation in accompanying his wife during pregnancy and the delivery process. The data used in this study was from an Indonesian Demographic Health Survey 2012. The study used binary logistic regression as the analysis method. The result showed as many as 8,237 husbands accompanied their wife in antenatal care and the delivery process. The significant variables affecting the husband participation are the age of the wife, the education of wife, the education of the husband, the occupational status of the wife and the husband, the number of children, pregnancy status, and residency region. The possibility for a husband to accompany his wife is larger in several factors, such as the wife being between the ages of 21 - 35 years old, a husband who minimally graduated from junior high school, a working husband, as well as a wife, and the number of children less than and equal to two and the expected pregnancy. The government should consider those factors to create policy related women’s health and integrate the factors into various sectors.

Individual Differences in Amygdala-Medial Prefrontal Anatomy Link Negative Affect, Impaired Social Functioning, and Polygenic Depression Risk

PubMed Central

Holmes, Avram J.; Lee, Phil H.; Hollinshead, Marisa O.; Bakst, Leah; Roffman, Joshua L.; Smoller, Jordan W.; Buckner, Randy L.

2013-01-01

Individual differences in affective and social processes may arise from variability in amygdala-medial prefrontal (mPFC) circuitry and related genetic heterogeneity. To explore this possibility in humans, we examined the structural correlates of trait negative affect in a sample of 1050 healthy young adults with no history of psychiatric illness. Analyses revealed that heightened negative affect was associated with increased amygdala volume and reduced thickness in a left mPFC region encompassing the subgenual and rostral anterior cingulate cortex. The most extreme individuals displayed an inverse correlation between amygdala volume and mPFC thickness, suggesting that imbalance between these structures is linked to negative affect in the general population. Subgroups of participants were further evaluated on social (n = 206) and emotional (n = 533) functions. Individuals with decreased mPFC thickness exhibited the poorest social cognition and were least able to correctly identify facial emotion. Given prior links between disrupted amygdala–mPFC circuitry and the presence of major depressive disorder (MDD), we explored whether the individual differences in anatomy observed here in healthy young adults were associated with polygenic risk for MDD (n = 438) using risk scores derived from a large genome-wide association analysis (n = 18,759). Analyses revealed associations between increasing polygenic burden for MDD and reduced cortical thickness in the left mPFC. These collective findings suggest that, within the healthy population, there is significant variability in amygdala–mPFC circuitry that is associated with poor functioning across affective and social domains. Individual differences in this circuitry may arise, in part, from common genetic variability that contributes to risk for MDD. PMID:23238724

Anxiety, affect, self-esteem, and stress: mediation and moderation effects on depression.

PubMed

Nima, Ali Al; Rosenberg, Patricia; Archer, Trevor; Garcia, Danilo

2013-01-01

Mediation analysis investigates whether a variable (i.e., mediator) changes in regard to an independent variable, in turn, affecting a dependent variable. Moderation analysis, on the other hand, investigates whether the statistical interaction between independent variables predict a dependent variable. Although this difference between these two types of analysis is explicit in current literature, there is still confusion with regard to the mediating and moderating effects of different variables on depression. The purpose of this study was to assess the mediating and moderating effects of anxiety, stress, positive affect, and negative affect on depression. Two hundred and two university students (males  = 93, females  = 113) completed questionnaires assessing anxiety, stress, self-esteem, positive and negative affect, and depression. Mediation and moderation analyses were conducted using techniques based on standard multiple regression and hierarchical regression analyses. The results indicated that (i) anxiety partially mediated the effects of both stress and self-esteem upon depression, (ii) that stress partially mediated the effects of anxiety and positive affect upon depression, (iii) that stress completely mediated the effects of self-esteem on depression, and (iv) that there was a significant interaction between stress and negative affect, and between positive affect and negative affect upon depression. The study highlights different research questions that can be investigated depending on whether researchers decide to use the same variables as mediators and/or moderators.

Hierarchical Synthesis of Coastal Ecosystem Health Indicators at Karimunjawa National Marine Park

NASA Astrophysics Data System (ADS)

Danu Prasetya, Johan; Ambariyanto; Supriharyono; Purwanti, Frida

2018-02-01

The coastal ecosystem of Karimunjawa National Marine Park (KNMP) is facing various pressures, including from human activity. Monitoring the health condition of coastal ecosystems periodically is needed as an evaluation of the ecosystem condition. Systematic and consistent indicators are needed in monitoring of coastal ecosystem health. This paper presents hierarchical synthesis of coastal ecosystem health indicators using Analytic Hierarchy Process (AHP) method. Hierarchical synthesis is obtained from process of weighting by paired comparison based on expert judgments. The variables of coastal ecosystem health indicators in this synthesis consist of 3 level of variable, i.e. main variable, sub-variable and operational variable. As a result of assessment, coastal ecosystem health indicators consist of 3 main variables, i.e. State of Ecosystem, Pressure and Management. Main variables State of Ecosystem and Management obtain the same value i.e. 0.400, while Pressure value was 0.200. Each main variable consist of several sub-variable, i.e. coral reef, reef fish, mangrove and seagrass for State of Ecosystem; fisheries and marine tourism activity for Pressure; planning and regulation, institutional and also infrastructure and financing for Management. The highest value of sub-variable of main variable State of Ecosystem, Pressure and Management were coral reef (0.186); marine tourism pressure (0.133) and institutional (0.171), respectively. The highest value of operational variable of main variable State of Ecosystem, Pressure and Management were percent of coral cover (0.058), marine tourism pressure (0.133) and presence of zonation plan, regulation also socialization of monitoring program (0.53), respectively. Potential pressure from marine tourism activity is the variable that most affect the health of the ecosystem. The results of this research suggest that there is a need to develop stronger conservation strategies to facing with pressures from marine tourism activities.

Effects of differentiated music on cycling time trial.

PubMed

Lim, H B T; Atkinson, G; Karageorghis, C I; Eubank, M R; Eubank, M M

2009-06-01

The aim of this study was to investigate the effects of music introduced and removed during a 10-km cycling time trial with reference to Rejeski's parallel processing theory and Karageorghis, Terry and Lane's conceptual framework for the prediction of responses to asynchronous music during sub-maximal exercise. A range of performance variables, ratings of perceived exertion, positive affect, negative affect, and blood lactate were assessed. Eleven males (mean age=24.9, s=6.1 years) completed a 10-km time trial under three conditions; no music, music played initially then removed between 5-10 km, and music played between 5-10 km only. Variables of time, power, cadence, speed, RPE, blood lactate, positive and negative affect were analysed using a ConditionxDistance ANOVA. There was no significant main effect for music conditions for the performance variables, perceived exertion, blood lactate, and affect (p>0.05). Nevertheless, a significant interaction effect for ConditionxDistance was found for cycling speed, with participants cycling 1-1.25 km/h faster at the start of the music introduced time trial than in both the music removed and no music time trials (p<0.05). The results indicate that performance and affect during a 10 km time trial are influenced by the introduction and/or removal of music during exercise and this finding can be used to extend current theory as it does not specifically address the periodic use music. The fact that participants exercised harder when they expected music to be introduced at a later stage illustrates the behavioural influences that music can engender during self-paced exercise.

Combining nutrition, food science and engineering in developing solutions to Inflammatory bowel diseases--omega-3 polyunsaturated fatty acids as an example.

PubMed

Ferguson, Lynnette R; Smith, Bronwen G; James, Bryony J

2010-10-01

The Inflammatory bowel diseases, Crohn's disease and ulcerative colitis, are debilitating conditions, characterised by lifelong sensitivity to certain foods, and often a need for surgery and life-long medication. The anti-inflammatory effects of long chain omega-3 polyunsaturated acids justify their inclusion in enteral nutrition formulas that have been associated with disease remission. However, there have been variable data in clinical trials to test supplementary omega-3 polyunsaturated fatty acids in inducing or maintaining remission in these diseases. Although variability in trial design has been suggested as a major factor, we suggest that variability in processing and presentation of the products may be equally or more important. The nature of the source, and rapidity of getting the fish or other food source to processing or to market, will affect the percentage of the various fatty acids, possible presence of heavy metal contaminants and oxidation status of the various fatty acids. For dietary supplements or fortified foods, whether the product is encapsulated or not, whether storage is under nitrogen or not, and length of time between harvest, processing and marketing will again profoundly affect the properties of the final product. Clinical trials to test efficacy of these products in IBD to date have utilised the relevant skills of pharmacology and gastroenterology. We suggest that knowledge from food science, nutrition and engineering will be essential to establish the true role of this important group of compounds in these diseases. This journal is © The Royal Society of Chemistry 2010

A cognitive developmental approach to variability in the psychotherapeutic process with adolescents.

PubMed

Gunning, C; Verheij, F

1990-01-01

Formulated from a cognitive frame of reference, psychodynamic therapy can be viewed as acting on one of the three aspects (feeling, thought, action) in order to influence or change the client's action and thought schemes. In this paper the consequences of the interaction of cognition and emotion for psychotherapeutic practice with adolescents are explored. Knowledge of cognitive development is supposed to be important for the therapist because, from Piaget's viewpoint, the structures of affect are cognitive structures. Moreover a great variability exists in cognitive development between adolescents. This variability is due to individual, family and social variables. The cognitive structural developmental model, the relation between emotional and cognitive development and the afore-mentioned variables are discussed. Consequences are psychotherapeutic practice with adolescents are described and short case histories are given. The authors conclude that in psychotherapeutic practice psychodynamic theory and cognitive structural theory can complete each other.

Tuned Normalization Explains the Size of Attention Modulations

PubMed Central

Ni, Amy M.; Ray, Supratim; Maunsell, John H. R.

2012-01-01

SUMMARY The effect of attention on firing rates varies considerably within a single cortical area. The firing rate of some neurons is greatly modulated by attention while others are hardly affected. The reason for this variability across neurons is unknown. We found that the variability in attention modulation across neurons in area MT of macaques can be well explained by variability in the strength of tuned normalization across neurons. The presence of tuned normalization also explains a striking asymmetry in attention effects within neurons: when two stimuli are in a neuron’s receptive field, directing attention to the preferred stimulus modulates firing rates more than directing attention to the non-preferred stimulus. These findings show that much of the neuron-to-neuron variability in modulation of responses by attention depends on variability in the way the neurons process multiple stimuli, rather than differences in the influence of top-down signals related to attention. PMID:22365552

Remote sensing and avian influenza: A review of image processing methods for extracting key variables affecting avian influenza virus survival in water from Earth Observation satellites

NASA Astrophysics Data System (ADS)

Tran, Annelise; Goutard, Flavie; Chamaillé, Lise; Baghdadi, Nicolas; Lo Seen, Danny

2010-02-01

Recent studies have highlighted the potential role of water in the transmission of avian influenza (AI) viruses and the existence of often interacting variables that determine the survival rate of these viruses in water; the two main variables are temperature and salinity. Remote sensing has been used to map and monitor water bodies for several decades. In this paper, we review satellite image analysis methods used for water detection and characterization, focusing on the main variables that influence AI virus survival in water. Optical and radar imagery are useful for detecting water bodies at different spatial and temporal scales. Methods to monitor the temperature of large water surfaces are also available. Current methods for estimating other relevant water variables such as salinity, pH, turbidity and water depth are not presently considered to be effective.

Tuned normalization explains the size of attention modulations.

PubMed

Ni, Amy M; Ray, Supratim; Maunsell, John H R

2012-02-23

The effect of attention on firing rates varies considerably within a single cortical area. The firing rate of some neurons is greatly modulated by attention while others are hardly affected. The reason for this variability across neurons is unknown. We found that the variability in attention modulation across neurons in area MT of macaques can be well explained by variability in the strength of tuned normalization across neurons. The presence of tuned normalization also explains a striking asymmetry in attention effects within neurons: when two stimuli are in a neuron's receptive field, directing attention to the preferred stimulus modulates firing rates more than directing attention to the nonpreferred stimulus. These findings show that much of the neuron-to-neuron variability in modulation of responses by attention depends on variability in the way the neurons process multiple stimuli, rather than differences in the influence of top-down signals related to attention. Copyright © 2012 Elsevier Inc. All rights reserved.

Testing for Neuropsychological Endophenotypes in Siblings Discordant for ADHD

PubMed Central

Bidwell, L. Cinnamon; Willcutt, Erik G.; DeFries, John C.; Pennington, Bruce F.

2007-01-01

Objective Neurocognitive deficits associated with attention deficit-hyperactivity disorder (ADHD) may be useful intermediate endophenotypes for determining specific genetic pathways that contribute to ADHD. Methods This study administered 17 measures from prominent neuropsychological theories of ADHD (executive function, processing speed, arousal regulation and motivation/delay aversion) in dizygotic (DZ) twin pairs discordant for ADHD and control twin pairs (ages 8–18) in order to compare performance between twins affected with ADHD (n = 266), their unaffected co-twins (n = 228), and control children from twin pairs without ADHD or learning difficulties (n = 332). Results ADHD subjects show significant impairment on executive function, processing speed, and response variability measures compared to control subjects. Unaffected cotwins of ADHD subjects are significantly impaired on nearly all the same measures as their ADHD siblings, even when subclinical symptoms of ADHD are controlled. Conclusion Executive function, processing speed, and response variability deficits may be useful endophenotypes for genetic studies of ADHD. PMID:17585884

Punishment induced behavioural and neurophysiological variability reveals dopamine-dependent selection of kinematic movement parameters

PubMed Central

Galea, Joseph M.; Ruge, Diane; Buijink, Arthur; Bestmann, Sven; Rothwell, John C.

2013-01-01

Action selection describes the high-level process which selects between competing movements. In animals, behavioural variability is critical for the motor exploration required to select the action which optimizes reward and minimizes cost/punishment, and is guided by dopamine (DA). The aim of this study was to test in humans whether low-level movement parameters are affected by punishment and reward in ways similar to high-level action selection. Moreover, we addressed the proposed dependence of behavioural and neurophysiological variability on DA, and whether this may underpin the exploration of kinematic parameters. Participants performed an out-and-back index finger movement and were instructed that monetary reward and punishment were based on its maximal acceleration (MA). In fact, the feedback was not contingent on the participant’s behaviour but pre-determined. Blocks highly-biased towards punishment were associated with increased MA variability relative to blocks with either reward or without feedback. This increase in behavioural variability was positively correlated with neurophysiological variability, as measured by changes in cortico-spinal excitability with transcranial magnetic stimulation over the primary motor cortex. Following the administration of a DA-antagonist, the variability associated with punishment diminished and the correlation between behavioural and neurophysiological variability no longer existed. Similar changes in variability were not observed when participants executed a pre-determined MA, nor did DA influence resting neurophysiological variability. Thus, under conditions of punishment, DA-dependent processes influence the selection of low-level movement parameters. We propose that the enhanced behavioural variability reflects the exploration of kinematic parameters for less punishing, or conversely more rewarding, outcomes. PMID:23447607

Below room temperature: How the photocatalytic activity of dense and mesoporous TiO2 coatings is affected

NASA Astrophysics Data System (ADS)

Cedillo-González, Erika Iveth; Riccò, Raffaele; Costacurta, Stefano; Siligardi, Cristina; Falcaro, Paolo

2018-03-01

Different parameters such as morphology, porosity, crystalline phase or doping agents affect the self-cleaning performance of photocatalytic TiO2-based coatings. However, also environmental conditions have been found to play a major role on the photocatalytic self-cleaning property. Substrate temperature is a significant environmental variable that can drastically affect this process. This variable becomes of great importance especially for outdoor applications: many self-cleaning photocatalytic materials have been designed to be exposed to outdoor environments and consequently, can be exposed to variable temperatures depending on the season of the year and the typical weather of the geographical zone. Thus, understanding the influence of the most common outdoor temperatures on the self-cleaning performance of TiO2-based coatings is essential for the fabrication of any kind of photocatalytic self-cleaning materials (fabricated by coating technology) that is expected to be subjected to outdoor environments. In this work, the photocatalytic activity was studied by Fourier Transformed Infrared (FTIR) Spectroscopy varying the temperature in the 0 to 30 °C range for dense and mesoporous TiO2 coatings. The temperature conditions at which these coatings present better performances were identified, providing a deeper insight for the practical application of TiO2-based self-cleaning coatings.

ERP correlates of word production predictors in picture naming: a trial by trial multiple regression analysis from stimulus onset to response.

PubMed

Valente, Andrea; Bürki, Audrey; Laganaro, Marina

2014-01-01

A major effort in cognitive neuroscience of language is to define the temporal and spatial characteristics of the core cognitive processes involved in word production. One approach consists in studying the effects of linguistic and pre-linguistic variables in picture naming tasks. So far, studies have analyzed event-related potentials (ERPs) during word production by examining one or two variables with factorial designs. Here we extended this approach by investigating simultaneously the effects of multiple theoretical relevant predictors in a picture naming task. High density EEG was recorded on 31 participants during overt naming of 100 pictures. ERPs were extracted on a trial by trial basis from picture onset to 100 ms before the onset of articulation. Mixed-effects regression models were conducted to examine which variables affected production latencies and the duration of periods of stable electrophysiological patterns (topographic maps). Results revealed an effect of a pre-linguistic variable, visual complexity, on an early period of stable electric field at scalp, from 140 to 180 ms after picture presentation, a result consistent with the proposal that this time period is associated with visual object recognition processes. Three other variables, word Age of Acquisition, Name Agreement, and Image Agreement influenced response latencies and modulated ERPs from ~380 ms to the end of the analyzed period. These results demonstrate that a topographic analysis fitted into the single trial ERPs and covering the entire processing period allows one to associate the cost generated by psycholinguistic variables to the duration of specific stable electrophysiological processes and to pinpoint the precise time-course of multiple word production predictors at once.

Symmetry breaking, mixing, instability, and low-frequency variability in a minimal Lorenz-like system.

PubMed

Lucarini, Valerio; Fraedrich, Klaus

2009-08-01

Starting from the classical Saltzman two-dimensional convection equations, we derive via a severe spectral truncation a minimal 10 ODE system which includes the thermal effect of viscous dissipation. Neglecting this process leads to a dynamical system which includes a decoupled generalized Lorenz system. The consideration of this process breaks an important symmetry and couples the dynamics of fast and slow variables, with the ensuing modifications to the structural properties of the attractor and of the spectral features. When the relevant nondimensional number (Eckert number Ec) is different from zero, an additional time scale of O(Ec(-1)) is introduced in the system, as shown with standard multiscale analysis and made clear by several numerical evidences. Moreover, the system is ergodic and hyperbolic, the slow variables feature long-term memory with 1/f(3/2) power spectra, and the fast variables feature amplitude modulation. Increasing the strength of the thermal-viscous feedback has a stabilizing effect, as both the metric entropy and the Kaplan-Yorke attractor dimension decrease monotonically with Ec. The analyzed system features very rich dynamics: it overcomes some of the limitations of the Lorenz system and might have prototypical value in relevant processes in complex systems dynamics, such as the interaction between slow and fast variables, the presence of long-term memory, and the associated extreme value statistics. This analysis shows how neglecting the coupling of slow and fast variables only on the basis of scale analysis can be catastrophic. In fact, this leads to spurious invariances that affect essential dynamical properties (ergodicity, hyperbolicity) and that cause the model losing ability in describing intrinsically multiscale processes.

A process model for the heat-affected zone microstructure evolution in duplex stainless steel weldments: Part I. the model

NASA Astrophysics Data System (ADS)

Hemmer, H.; Grong, Ø.

1999-11-01

The present investigation is concerned with modeling of the microstructure evolution in duplex stainless steels under thermal conditions applicable to welding. The important reactions that have been modeled are the dissolution of austenite during heating, subsequent grain growth in the delta ferrite regime, and finally, the decomposition of the delta ferrite to austenite during cooling. As a starting point, a differential formulation of the underlying diffusion problem is presented, based on the internal-state variable approach. These solutions are later manipulated and expressed in terms of the Scheil integral in the cases where the evolution equation is separable or can be made separable by a simple change of variables. The models have then been applied to describe the heat-affected zone microstructure evolution during both thick-plate and thin-plate welding of three commercial duplex stainless steel grades: 2205, 2304, and 2507. The results may conveniently be presented in the form of novel process diagrams, which display contours of constant delta ferrite grain size along with information about dissolution and reprecipitation of austenite for different combinations of weld input energy and peak temperature. These diagrams are well suited for quantitative readings and illustrate, in a condensed manner, the competition between the different variables that lead to structural changes during welding of duplex stainless steels.

Influence of attitudes and behavior of milkers on the hygienic and sanitary quality of milk

PubMed Central

Cassoli, Laerte D.; Machado, Paulo F.; Cerón-Muñoz, Mario Fernando

2017-01-01

Recognizing how human behaviors affect the milk process can be useful to understand variations in hygienic and sanitary parameters in bulk tank milk. Furthermore, this knowledge could be used to design management programs that guarantee milk quality, favoring the optimization of such processes. Forty-six milkers from the same number of dairy farms in Antioquia province (Colombia) were interviewed to establish the main factors associated to milk quality. Technical knowledge, motivations, and behavior of the personnel and its effect on hygienic and sanitary quality of milk were evaluated. Quality was assessed in terms of colony-forming units (CFU) and somatic cell count (SCC) in bulk tank milk. Two factors from a multivariate mixed data analysis were evaluated. One of those factors explained 9.51% of the total variability, related with in-farm availability and use of tools and the relationships between milker and manager. The other factor, associated with work environment and recognition, explained 6.97% of the total variability. The variables that best explained CFU levels were Knowledge of the udder condition at milking, and Milking type (parlor or pasture). The SCC was associated to knowledge of animal handling, schooling of milkers, milking site, and the groups derived from the cluster analysis by farm. In conclusion, milker attitudes and behaviors can affect CFU and SCC in bulk tank milk. PMID:28926583

Adaptive Neuro-Fuzzy Determination of the Effect of Experimental Parameters on Vehicle Agent Speed Relative to Vehicle Intruder.

PubMed

Shamshirband, Shahaboddin; Banjanovic-Mehmedovic, Lejla; Bosankic, Ivan; Kasapovic, Suad; Abdul Wahab, Ainuddin Wahid Bin

2016-01-01

Intelligent Transportation Systems rely on understanding, predicting and affecting the interactions between vehicles. The goal of this paper is to choose a small subset from the larger set so that the resulting regression model is simple, yet have good predictive ability for Vehicle agent speed relative to Vehicle intruder. The method of ANFIS (adaptive neuro fuzzy inference system) was applied to the data resulting from these measurements. The ANFIS process for variable selection was implemented in order to detect the predominant variables affecting the prediction of agent speed relative to intruder. This process includes several ways to discover a subset of the total set of recorded parameters, showing good predictive capability. The ANFIS network was used to perform a variable search. Then, it was used to determine how 9 parameters (Intruder Front sensors active (boolean), Intruder Rear sensors active (boolean), Agent Front sensors active (boolean), Agent Rear sensors active (boolean), RSSI signal intensity/strength (integer), Elapsed time (in seconds), Distance between Agent and Intruder (m), Angle of Agent relative to Intruder (angle between vehicles °), Altitude difference between Agent and Intruder (m)) influence prediction of agent speed relative to intruder. The results indicated that distance between Vehicle agent and Vehicle intruder (m) and angle of Vehicle agent relative to Vehicle Intruder (angle between vehicles °) is the most influential parameters to Vehicle agent speed relative to Vehicle intruder.

Speed, Variability, and Timing of Motor Output in ADHD: Which Measures are Useful for Endophenotypic Research?

PubMed Central

Altink, Marieke E.; Oosterlaan, Jaap; Beem, Leo; Buschgens, Cathelijne J. M.; Buitelaar, Jan; Sergeant, Joseph A.

2007-01-01

Attention-Deficit/Hyperactivity Disorder (ADHD) shares a genetic basis with motor coordination problems and probably motor timing problems. In line with this, comparable problems in motor timing should be observed in first degree relatives and might, therefore, form a suitable endophenotypic candidate. This hypothesis was investigated in 238 ADHD-families (545 children) and 147 control-families (271 children). A motor timing task was administered, in which children had to produce a 1,000 ms interval. In addition to this task, two basic motor tasks were administered to examine speed and variability of motor output, when no timing component was required. Results indicated that variability in motor timing is a useful endophenotypic candidate: It was clearly associated with ADHD, it was also present in non-affected siblings, and it correlated within families. Accuracy (under- versus over-production) in motor timing appeared less useful: Even though accuracy was associated with ADHD (probands and affected siblings had a tendency to under-produce the 1,000 ms interval compared to controls), non-affected siblings did not differ from controls and sibling correlations were only marginally significant. Slow and variable motor output without timing component also appears present in ADHD, but not in non-affected siblings, suggesting these deficits not to be related to a familial vulnerability for ADHD. Deficits in motor timing could not be explained by deficits already present in basic motor output without a timing component. This suggests abnormalities in motor timing were predominantly related to deficient motor timing processes and not to general deficient motor functioning. The finding that deficits in motor timing run in ADHD-families suggests this to be a fruitful domain for further exploration in relation to the genetic underpinnings of ADHD. PMID:18071893

Shifts in leaf litter breakdown along a forest-pasture-urban gradient in Andean streams.

PubMed

Iñiguez-Armijos, Carlos; Rausche, Sirkka; Cueva, Augusta; Sánchez-Rodríguez, Aminael; Espinosa, Carlos; Breuer, Lutz

2016-07-01

Tropical montane ecosystems of the Andes are critically threatened by a rapid land-use change which can potentially affect stream variables, aquatic communities, and ecosystem processes such as leaf litter breakdown. However, these effects have not been sufficiently investigated in the Andean region and at high altitude locations in general. Here, we studied the influence of land use (forest-pasture-urban) on stream physico-chemical variables (e.g., water temperature, nutrient concentration, and pH), aquatic communities (macroinvertebrates and aquatic fungi) and leaf litter breakdown rates in Andean streams (southern Ecuador), and how variation in those stream physico-chemical variables affect macroinvertebrates and fungi related to leaf litter breakdown. We found that pH, water temperature, and nutrient concentration increased along the land-use gradient. Macroinvertebrate communities were significantly different between land uses. Shredder richness and abundance were lower in pasture than forest sites and totally absent in urban sites, and fungal richness and biomass were higher in forest sites than in pasture and urban sites. Leaf litter breakdown rates became slower as riparian land use changed from natural to anthropogenically disturbed conditions and were largely determined by pH, water temperature, phosphate concentration, fungal activity, and single species of leaf-shredding invertebrates. Our findings provide evidence that leaf litter breakdown in Andean streams is sensitive to riparian land-use change, with urban streams being the most affected. In addition, this study highlights the role of fungal biomass and shredder species (Phylloicus; Trichoptera and Anchytarsus; Coleoptera) on leaf litter breakdown in Andean streams and the contribution of aquatic fungi in supporting this ecosystem process when shredders are absent or present low abundance in streams affected by urbanization. Finally, we summarize important implications in terms of managing of native vegetation and riparian buffers to promote ecological integrity and functioning of tropical Andean stream ecosystems.

Effect of process variables on the sulfate reduction process in bioreactors treating metal-containing wastewaters: factorial design and response surface analyses.

PubMed

Villa-Gomez, D K; Pakshirajan, K; Maestro, R; Mushi, S; Lens, P N L

2015-07-01

The individual and combined effect of the pH, chemical oxygen demand (COD) and SO4 (2-) concentration, metal to sulfide (M/S(2-)) ratio and hydraulic retention time (HRT) on the biological sulfate reduction (SR) process was evaluated in an inverse fluidized bed reactor by factorial design analysis (FDA) and response surface analysis (RSA). The regression-based model of the FDA described the experimental results well and revealed that the most significant variable affecting the process was the pH. The combined effect of the pH and HRT was barely observable, while the pH and COD concentration positive effect (up to 7 and 3 gCOD/L, respectively) enhanced the SR process. Contrary, the individual COD concentration effect only enhanced the COD removal efficiency, suggesting changes in the microbial pathway. The RSA showed that the M/S(2-) ratio determined whether the inhibition mechanism to the SR process was due to the presence of free metals or precipitated metal sulfides.

Randomized Trial of a Lifestyle Physical Activity Intervention for Breast Cancer Survivors: Effects on Transtheoretical Model Variables.

PubMed

Scruggs, Stacie; Mama, Scherezade K; Carmack, Cindy L; Douglas, Tommy; Diamond, Pamela; Basen-Engquist, Karen

2018-01-01

This study examined whether a physical activity intervention affects transtheoretical model (TTM) variables that facilitate exercise adoption in breast cancer survivors. Sixty sedentary breast cancer survivors were randomized to a 6-month lifestyle physical activity intervention or standard care. TTM variables that have been shown to facilitate exercise adoption and progress through the stages of change, including self-efficacy, decisional balance, and processes of change, were measured at baseline, 3 months, and 6 months. Differences in TTM variables between groups were tested using repeated measures analysis of variance. The intervention group had significantly higher self-efficacy ( F = 9.55, p = .003) and perceived significantly fewer cons of exercise ( F = 5.416, p = .025) at 3 and 6 months compared with the standard care group. Self-liberation, counterconditioning, and reinforcement management processes of change increased significantly from baseline to 6 months in the intervention group, and self-efficacy and reinforcement management were significantly associated with improvement in stage of change. The stage-based physical activity intervention increased use of select processes of change, improved self-efficacy, decreased perceptions of the cons of exercise, and helped participants advance in stage of change. These results point to the importance of using a theory-based approach in interventions to increase physical activity in cancer survivors.

Computer Optimization of Biodegradable Nanoparticles Fabricated by Dispersion Polymerization.

PubMed

Akala, Emmanuel O; Adesina, Simeon; Ogunwuyi, Oluwaseun

2015-12-22

Quality by design (QbD) in the pharmaceutical industry involves designing and developing drug formulations and manufacturing processes which ensure predefined drug product specifications. QbD helps to understand how process and formulation variables affect product characteristics and subsequent optimization of these variables vis-à-vis final specifications. Statistical design of experiments (DoE) identifies important parameters in a pharmaceutical dosage form design followed by optimizing the parameters with respect to certain specifications. DoE establishes in mathematical form the relationships between critical process parameters together with critical material attributes and critical quality attributes. We focused on the fabrication of biodegradable nanoparticles by dispersion polymerization. Aided by a statistical software, d-optimal mixture design was used to vary the components (crosslinker, initiator, stabilizer, and macromonomers) to obtain twenty nanoparticle formulations (PLLA-based nanoparticles) and thirty formulations (poly-ɛ-caprolactone-based nanoparticles). Scheffe polynomial models were generated to predict particle size (nm), zeta potential, and yield (%) as functions of the composition of the formulations. Simultaneous optimizations were carried out on the response variables. Solutions were returned from simultaneous optimization of the response variables for component combinations to (1) minimize nanoparticle size; (2) maximize the surface negative zeta potential; and (3) maximize percent yield to make the nanoparticle fabrication an economic proposition.

Self-efficacy with application to nursing education: a concept analysis.

PubMed

Robb, Meigan

2012-01-01

Concept analysis and self-efficacy. This article analyzes the concept self-efficacy and its relationship to nursing education using Walker and Avant's methodology. Published literature. Nursing literature suggests increasing students' perceived self-efficacy will help to narrow the theory-practice gap. Self-efficacy is a cognitive variable that affects performance behaviors and affective processes. Perceived self-efficacy can be influenced by a direct experience, vicarious experience, or verbal persuasion. Individuals with high levels of self-efficacy demonstrate the defining attributes of confidence, perceived capability, and perseverance. © 2012 Wiley Periodicals, Inc.

Method of predicting a change in an economy

DOEpatents

Pryor, Richard J [Albuquerque, NM; Basu, Nipa [Albany, NY

2006-01-10

An economy whose activity is to be predicted comprises a plurality of decision makers. Decision makers include, for example, households, government, industry, and banks. The decision makers are represented by agents, where an agent can represent one or more decision makers. Each agent has decision rules that determine the agent's actions. Each agent can affect the economy by affecting variable conditions characteristic of the economy or the internal state of other agents. Agents can communicate actions through messages. On a multiprocessor computer, the agents can be assigned to processing elements.

Interannual variability of terrestrial NEP and its attributions to carbon uptake amplitude and period

NASA Astrophysics Data System (ADS)

Niu, S.

2015-12-01

Earth system exhibits strong interannual variability (IAV) in the global carbon cycle as reflected in the year-to-year anomalies of the atmospheric CO2 concentration. Although various analyses suggested that land ecosystems contribute mostly to the IAV of atmospheric CO2 concentration, processes leading to the IAV in the terrestrial carbon (C) cycle are far from clear and hinder our effort in predicting the IAV of global C cycle. Previous studies on IAV of global C cycle have focused on the regulation of climatic variables in tropical or semiarid areas, but generated inconsistent conclusions. Using long-term eddy-flux measurements of net ecosystem production (NEP), atmospheric CO2 inversion NEP, and the MODIS-derived gross primary production (GPP), we demonstrate that seasonal carbon uptake amplitude (CUA) and period (CUP) are two key processes that control the IAV in the terrestrial C cycle. The two processes together explain 78% of the variations in the IAV in eddy covariance NEP, 70% in global atmospheric inversed NEP, and 53% in the IAV of GPP. Moreover, the three lines of evidence consistently show that variability in CUA is much more important than that of CUP in determining the variation of NEP at most eddy-flux sites, and most grids of global NEP and GPP. Our results suggest that the maximum carbon uptake potential in the peak-growing season is a determinant process of global C cycle internnual variability and carbon uptake period may play less important role than previous expectations. This study uncovers the most parsimonious, proximate processes underlying the IAV in global C cycle of the Earth system. Future research is needed to identify how climate factors affect the IAV in terrestrial C cycle through their influence on CUA and CUP.

Optimization of nanoparticles for cardiovascular tissue engineering.

PubMed

Izadifar, Mohammad; Kelly, Michael E; Haddadi, Azita; Chen, Xiongbiao

2015-06-12

Nano-particulate delivery systems have increasingly been playing important roles in cardiovascular tissue engineering. Properties of nanoparticles (e.g. size, polydispersity, loading capacity, zeta potential, morphology) are essential to system functions. Notably, these characteristics are regulated by fabrication variables, but in a complicated manner. This raises a great need to optimize fabrication process variables to ensure the desired nanoparticle characteristics. This paper presents a comprehensive experimental study on this matter, along with a novel method, the so-called Geno-Neural approach, to analyze, predict and optimize fabrication variables for desired nanoparticle characteristics. Specifically, ovalbumin was used as a protein model of growth factors used in cardiovascular tissue regeneration, and six fabrication variables were examined with regard to their influence on the characteristics of nanoparticles made from high molecular weight poly(lactide-co-glycolide). The six-factor five-level central composite rotatable design was applied to the conduction of experiments, and based on the experimental results, a geno-neural model was developed to determine the optimum fabrication conditions. For desired particle sizes of 150, 200, 250 and 300 nm, respectively, the optimum conditions to achieve the low polydispersity index, higher negative zeta potential and higher loading capacity were identified based on the developed geno-neural model and then evaluated experimentally. The experimental results revealed that the polymer and the external aqueous phase concentrations and their interactions with other fabrication variables were the most significant variables to affect the size, polydispersity index, zeta potential, loading capacity and initial burst release of the nanoparticles, while the electron microscopy images of the nanoparticles showed their spherical geometries with no sign of large pores or cracks on their surfaces. The release study revealed that the onset of the third phase of release can be affected by the polymer concentration. Circular dichroism spectroscopy indicated that ovalbumin structural integrity is preserved during the encapsulation process. Findings from this study would greatly contribute to the design of high molecular weight poly(lactide-co-glycolide) nanoparticles for prolonged release patterns in cardiovascular engineering.

Water vapour fluxes trends on different time scales and their relationship with weather and soil drivers: a case study from a dehesa site in South Spain

NASA Astrophysics Data System (ADS)

Polo, María José; Egüen, Marta; Andreu, Ana; Carpintero, Elisabet; Gómez-Giráldez, Pedro; Patrocinio González-Dugo, María

2017-04-01

Water vapour fluxes between the soil surface and the atmosphere constitute one of the most important components of the water cycle in the continental areas. Their regime directly affect the availability of water to plants, water storage in surface bodies, air humidity in the boundary layer, snow persistence… among others, and the list of indirectly affected processes comprises a large number of components. Water potential or wetness gradients are some of the main drivers of water vapour fluxes to the atmosphere; soil humidity is usually monitored as key variable in many hydrological and environmental studies, and its estimated series are used to calibrate and validate the modelling of certain hydrological processes. However, such results may differ when water fluxes are used instead of water state variables, such as humidity. This work shows the analysis of high resolution water vapour fluxes series from a dehesa area in South Spain where a complete energy and water fluxes/variables monitoring site has been operating for the last four years. The results include pasture and tree vegetated control points. The daily water budget calculation on both types of sites has been performed from weather and energy fluxes measurements, and soil moisture measurements, and the results have been aggregated on a weekly, monthly and seasonal basis. Comparison between observed trends of soil moisture and calculated trends of water vapour fluxes is included to show the differences arising in terms of the regime of the dominant weather variables in this type of ecosystems. The results identify significant thresholds for each weather variable driver and highlight the importance of the wind regime, which is the somehow forgotten variable in future climate impacts on hydrology. Further work is being carried out to assess water cycle potential trends under future climate conditions and their impacts on the vegetation in dehesa ecosystems.

Clinical Significance of Mobile Health Assessed Sleep Duration and Variability in Bipolar Disorder

PubMed Central

Kaufmann, Christopher N.; Gershon, Anda; Eyler, Lisa T.; Depp, Colin A.

2016-01-01

OBJECTIVE Sleep disturbances are prevalent, persistent, and impairing features of bipolar disorder. However, the near-term and cumulative impact of the severity and variability of sleep disturbances on symptoms and functioning remains unclear. We examined self-reported daily sleep duration and variability in relation to mood symptoms, medication adherence, cognitive functioning, and concurrent daily affect. METHODS Forty-one outpatients diagnosed with bipolar disorder were asked to provide daily reports of sleep duration and affect collected via ecological momentary assessment with smartphones over eleven weeks. Measures of depressive and manic symptoms, medication adherence, and cognitive function were collected at baseline and concurrent assessment of affect were collected daily. Analyses examined whether sleep duration or variability were associated with baseline measures and changes in same-day or next-day affect. RESULTS Greater sleep duration variability (but not average sleep duration) was associated with greater depressive and manic symptom severity, and lower medication adherence at baseline, and with lower and more variable ratings of positive affect and higher ratings of negative affect. Sleep durations shorter than 7-8 hours were associated with lower same-day ratings of positive and higher same-day ratings of negative affect, however this did not extend to next-day affect. CONCLUSIONS Greater cumulative day-to-day sleep duration variability, but not average sleep duration, was related to more severe mood symptoms, lower self-reported medication adherence and higher levels of negative affect. Bouts of short- or long-duration sleep had transient impact on affect. Day-to-day sleep variability may be important to incorporate into clinical assessment of sleep disturbances in bipolar disorder. PMID:27451108

Clinical significance of mobile health assessed sleep duration and variability in bipolar disorder.

PubMed

Kaufmann, Christopher N; Gershon, Anda; Eyler, Lisa T; Depp, Colin A

2016-10-01

Sleep disturbances are prevalent, persistent, and impairing features of bipolar disorder. However, the near-term and cumulative impact of the severity and variability of sleep disturbances on symptoms and functioning remains unclear. We examined self-reported daily sleep duration and variability in relation to mood symptoms, medication adherence, cognitive functioning, and concurrent daily affect. Forty-one outpatients diagnosed with bipolar disorder were asked to provide daily reports of sleep duration and affect collected via ecological momentary assessment with smartphones over eleven weeks. Measures of depressive and manic symptoms, medication adherence, and cognitive function were collected at baseline and concurrent assessment of affect were collected daily. Analyses examined whether sleep duration or variability were associated with baseline measures and changes in same-day or next-day affect. Greater sleep duration variability (but not average sleep duration) was associated with greater depressive and manic symptom severity, and lower medication adherence at baseline, and with lower and more variable ratings of positive affect and higher ratings of negative affect. Sleep durations shorter than 7-8 h were associated with lower same-day ratings of positive and higher same-day ratings of negative affect, however this did not extend to next-day affect. Greater cumulative day-to-day sleep duration variability, but not average sleep duration, was related to more severe mood symptoms, lower self-reported medication adherence and higher levels of negative affect. Bouts of short- or long-duration sleep had transient impact on affect. Day-to-day sleep variability may be important to incorporate into clinical assessment of sleep disturbances in bipolar disorder. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Socio-Moral Image Database (SMID): A novel stimulus set for the study of social, moral and affective processes.

PubMed

Crone, Damien L; Bode, Stefan; Murawski, Carsten; Laham, Simon M

2018-01-01

A major obstacle for the design of rigorous, reproducible studies in moral psychology is the lack of suitable stimulus sets. Here, we present the Socio-Moral Image Database (SMID), the largest standardized moral stimulus set assembled to date, containing 2,941 freely available photographic images, representing a wide range of morally (and affectively) positive, negative and neutral content. The SMID was validated with over 820,525 individual judgments from 2,716 participants, with normative ratings currently available for all images on affective valence and arousal, moral wrongness, and relevance to each of the five moral values posited by Moral Foundations Theory. We present a thorough analysis of the SMID regarding (1) inter-rater consensus, (2) rating precision, and (3) breadth and variability of moral content. Additionally, we provide recommendations for use aimed at efficient study design and reproducibility, and outline planned extensions to the database. We anticipate that the SMID will serve as a useful resource for psychological, neuroscientific and computational (e.g., natural language processing or computer vision) investigations of social, moral and affective processes. The SMID images, along with associated normative data and additional resources are available at https://osf.io/2rqad/.

Effect of interannual climate variability on carbon storage in Amazonian ecosystems

USGS Publications Warehouse

Tian, H.; Melillo, J.M.; Kicklighter, D.W.; McGuire, David A.; Helfrich, J. V. K.; Moore, B.; Vorosmarty, C.J.

1998-01-01

The Amazon Basin contains almost one-half of the world's undisturbed tropical evergreen forest as well as large areas of tropical savanna. The forests account for about 10 per cent of the world's terrestrial primary productivity and for a similar fraction of the carbon stored in land ecosystems, and short-term field measurements suggest that these ecosystems are globally important carbon sinks. But tropical land ecosystems have experienced substantial interannual climate variability owing to frequent El Nino episodes in recent decades. Of particular importance to climate change policy is how such climate variations, coupled with increases in atmospheric CO2 concentration, affect terrestrial carbon storage. Previous model analyses have demonstrated the importance of temperature in controlling carbon storage. Here we use a transient process-based biogeochemical model of terrestrial ecosystems to investigate interannual variations of carbon storage in undisturbed Amazonian ecosystems in response to climate variability and increasing atmospheric CO2 concentration during the period 1980 to 1994. In El Nino years, which bring hot, dry weather to much of the Amazon region, the ecosystems act as a source of carbon to the atmosphere (up to 0.2 petagrams of carbon in 1987 and 1992). In other years, these ecosystems act as a carbon sink (up to 0.7 Pg C in 1981 and 1993). These fluxes are large; they compare to a 0.3 Pg C per year source to the atmosphere associated with deforestation in the Amazon Basin in the early 1990s. Soil moisture, which is affected by both precipitation and temperature, and which affects both plant and soil processes, appears to be an important control on carbon storage.

The "Trouble Shooting" Checklist: A Manual to Aid Educational Change Agents in the Prediction of Organizational Change Potential.

ERIC Educational Resources Information Center

Manning, Brad A.

The first section of this manual contains a selective review of organizational change literature which focuses on predictive institutional variables as they affect the adoption-diffusion process. The second section describes the development of the Trouble Shooting Checklist (TSC). The third section presents two Trouble Shooting Checklists (TSC-A…

Factors affecting ammonium uptake in streams - an inter-biome perspective

Treesearch

Jackson R Webster; Partick J. Mulholland; Jennifer L. Tanks; H. Maurice Valett; Walter K. Dodds; Bruce J. Peterson; William B. Bowden; Clifford N. Dahm; Stuart Findlay; Stanley V. Gregory; Nancy B. Grimm; Stephen K. Hamilton; Sherri L. Johnson; Eugenia Marti; William H. McDowell; Judy L. Meyer; Donna D. Morrall; Steven A. Thomas; Wilfred M. Wollhem

2003-01-01

1. The Lotic Intersite Nitrogen experiment (LINX) was a coordinated study of the relationships between North American biomes and factors governing ammonium uptake in streams. Our objective was to relate inter-biome variability of ammonium uptake to physical, chemical and biological processes. 2. Data were collected from 11 streams ranging from arctic to tropical and...

Daily Landsat-scale evapotranspiration estimation over a managed pine plantation in North Carolina, USA using multi-satellite data fusion

USDA-ARS?s Scientific Manuscript database

As a primary flux in the global water cycle, evapotranspiration (ET) connects hydrologic and biological processes and is directly affected by water and land management, land use change and climate variability. The Two Source Energy Balance (TSEB) model has been widely applied to quantify field- to g...

Effects of Cognitive Styles on an MSN Virtual Learning Companion System as an Adjunct to Classroom Instructions

ERIC Educational Resources Information Center

Hsieh, Sheng-Wen

2011-01-01

This study designed a chatbot system, Confucius, as a MSN virtual learning companion to examine how specific application design variables within educational software affect the learning process of subjects as defined by the cognitive continuum of field-dependent and field-independent learners. 104 college students participated in a 12 week…

Methods Improvement of the Fluorescent Penetrant Inspection (FPI) Process.

DTIC Science & Technology

1980-10-01

also affect his ability. There has bieen recetnt eff’o to automiate V14. unfo~rtunatelyv, the humnan factors of’ F14I currentl lv cannot be replaced liY...control, and (6) human factors like variability of training, experience, and job interest. TECHNICAL APPROACH The objective of’ Phase II was to evaluate

Optimization of Processing Variables Which Affect Adhesion of Organic Coatings to Anodized Aluminum Alloys

DTIC Science & Technology

1975-10-01

DC anodizing all adhesion values were lower but almost equal. 36 mnamnminmh TABU X SWOT OF EFFECT OF CURRaTT DEÄITT, TIME ABD SEAUK OF CHJOOC...Continuum Interpretation for Fracture and Adhesion", J. Appl . Polymer Science, 1^, 29 (I969) 3. Williams, M. L., "Stress Singularities, Adhesion, and

L2 Motivation, Anxiety and Self-Efficacy: The Interrelationship of Individual Variables in the Secondary School Context

ERIC Educational Resources Information Center

Piniel, Katalin; Csizér, Kata

2013-01-01

Our study describes the relationship of second language learning motivation, self-efficacy, and anxiety; that is, how motivation, cognition, and affect might interact during the process of second language learning. Questionnaire data were collected from 236 Hungarian students studying at various secondary schools. Structural equation modeling was…

Gathering Time-Series Data for Evaluating Behavior-Change Campaigns in Developing Countries: Reactivity of Diaries and Interviews

ERIC Educational Resources Information Center

Tobias, Robert; Inauen, Jennifer

2010-01-01

Gathering time-series data of behaviors and psychological variables is important to understand, guide, and evaluate behavior-change campaigns and other change processes. However, repeated measurement can affect the phenomena investigated, particularly frequent face-to-face interviews, which are often the only option in developing countries. This…

A review of blood sample handling and pre-processing for metabolomics studies.

PubMed

Hernandes, Vinicius Veri; Barbas, Coral; Dudzik, Danuta

2017-09-01

Metabolomics has been found to be applicable to a wide range of clinical studies, bringing a new era for improving clinical diagnostics, early disease detection, therapy prediction and treatment efficiency monitoring. A major challenge in metabolomics, particularly untargeted studies, is the extremely diverse and complex nature of biological specimens. Despite great advances in the field there still exist fundamental needs for considering pre-analytical variability that can introduce bias to the subsequent analytical process and decrease the reliability of the results and moreover confound final research outcomes. Many researchers are mainly focused on the instrumental aspects of the biomarker discovery process, and sample related variables sometimes seem to be overlooked. To bridge the gap, critical information and standardized protocols regarding experimental design and sample handling and pre-processing are highly desired. Characterization of a range variation among sample collection methods is necessary to prevent results misinterpretation and to ensure that observed differences are not due to an experimental bias caused by inconsistencies in sample processing. Herein, a systematic discussion of pre-analytical variables affecting metabolomics studies based on blood derived samples is performed. Furthermore, we provide a set of recommendations concerning experimental design, collection, pre-processing procedures and storage conditions as a practical review that can guide and serve for the standardization of protocols and reduction of undesirable variation. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Unsaturated flow processes in structurally-variable pathways in wildfire-affected soils and ash

NASA Astrophysics Data System (ADS)

Ebel, B. A.

2016-12-01

Prediction of flash flood and debris flow generation in wildfire-affected soils and ash hinges on understanding unsaturated flow processes. Water resources issues, such as groundwater recharge, also rely on our ability to quantify subsurface flow. Soil-hydraulic property data provide insight into unsaturated flow processes and timescales. A literature review and synthesis of existing data from the literature for wildfire-affected soils, including ash and unburned soils, facilitated calculating metrics and timescales of hydrologic response related to infiltration and surface runoff generation. Sorptivity (S) and the Green-Ampt wetting front parameter (Ψf) were significantly lower in burned soils compared to unburned soils, while field-saturated hydraulic conductivity (Kfs) was not significantly different. The magnitude and duration of the influence of capillarity was substantially reduced in burned soils, leading to faster ponding times in response to rainfall. Ash had large values of S and Kfs compared to unburned and burned soils but intermediate values of Ψf, suggesting that ash has long ponding times in response to rainfall. The ratio of S2/Kfs was nearly constant ( 100 mm) for unburned soils, but was more variable in burned soils. Post-wildfire changes in this ratio suggested that unburned soils had a balance between gravity and capillarity contributions to infiltration, which may depend on soil organic matter, while burning shifted infiltration more towards gravity contributions by reducing S. Taken together, the changes in post-wildfire soil-hydraulic properties increased the propensity for surface runoff generation and may have enhanced subsurface preferential flow through pathways altered by wildfire.

Intra-individual variability in information processing speed reflects white matter microstructure in multiple sclerosis.

PubMed

Mazerolle, Erin L; Wojtowicz, Magdalena A; Omisade, Antonina; Fisk, John D

2013-01-01

Slowed information processing speed is commonly reported in persons with multiple sclerosis (MS), and is typically investigated using clinical neuropsychological tests, which provide sensitive indices of mean-level information processing speed. However, recent studies have demonstrated that within-person variability or intra-individual variability (IIV) in information processing speed may be a more sensitive indicator of neurologic status than mean-level performance on clinical tests. We evaluated the neural basis of increased IIV in mildly affected relapsing-remitting MS patients by characterizing the relation between IIV (controlling for mean-level performance) and white matter integrity using diffusion tensor imaging (DTI). Twenty women with relapsing-remitting MS and 20 matched control participants completed the Computerized Test of Information Processing (CTIP), from which both mean response time and IIV were calculated. Other clinical measures of information processing speed were also collected. Relations between IIV on the CTIP and DTI metrics of white matter microstructure were evaluated using tract-based spatial statistics. We observed slower and more variable responses on the CTIP in MS patients relative to controls. Significant relations between white matter microstructure and IIV were observed for MS patients. Increased IIV was associated with reduced integrity in more white matter tracts than was slowed information processing speed as measured by either mean CTIP response time or other neuropsychological test scores. Thus, despite the common use of mean-level performance as an index of cognitive dysfunction in MS, IIV may be more sensitive to the overall burden of white matter disease at the microstructural level. Furthermore, our study highlights the potential value of considering within-person fluctuations, in addition to mean-level performance, for uncovering brain-behavior relationships in neurologic disorders with widespread white matter pathology.

[Application of regression tree in analyzing the effects of climate factors on NDVI in loess hilly area of Shaanxi Province].

PubMed

Liu, Yang; Lü, Yi-he; Zheng, Hai-feng; Chen, Li-ding

2010-05-01

Based on the 10-day SPOT VEGETATION NDVI data and the daily meteorological data from 1998 to 2007 in Yan' an City, the main meteorological variables affecting the annual and interannual variations of NDVI were determined by using regression tree. It was found that the effects of test meteorological variables on the variability of NDVI differed with seasons and time lags. Temperature and precipitation were the most important meteorological variables affecting the annual variation of NDVI, and the average highest temperature was the most important meteorological variable affecting the inter-annual variation of NDVI. Regression tree was very powerful in determining the key meteorological variables affecting NDVI variation, but could not build quantitative relations between NDVI and meteorological variables, which limited its further and wider application.

Anxiety, Affect, Self-Esteem, and Stress: Mediation and Moderation Effects on Depression

PubMed Central

Nima, Ali Al; Rosenberg, Patricia; Archer, Trevor; Garcia, Danilo

2013-01-01

Background Mediation analysis investigates whether a variable (i.e., mediator) changes in regard to an independent variable, in turn, affecting a dependent variable. Moderation analysis, on the other hand, investigates whether the statistical interaction between independent variables predict a dependent variable. Although this difference between these two types of analysis is explicit in current literature, there is still confusion with regard to the mediating and moderating effects of different variables on depression. The purpose of this study was to assess the mediating and moderating effects of anxiety, stress, positive affect, and negative affect on depression. Methods Two hundred and two university students (males  = 93, females  = 113) completed questionnaires assessing anxiety, stress, self-esteem, positive and negative affect, and depression. Mediation and moderation analyses were conducted using techniques based on standard multiple regression and hierarchical regression analyses. Main Findings The results indicated that (i) anxiety partially mediated the effects of both stress and self-esteem upon depression, (ii) that stress partially mediated the effects of anxiety and positive affect upon depression, (iii) that stress completely mediated the effects of self-esteem on depression, and (iv) that there was a significant interaction between stress and negative affect, and between positive affect and negative affect upon depression. Conclusion The study highlights different research questions that can be investigated depending on whether researchers decide to use the same variables as mediators and/or moderators. PMID:24039896

Replication stress affects the fidelity of nucleosome-mediated epigenetic inheritance

PubMed Central

Li, Wenzhu; Yi, Jia; Agbu, Pamela; Zhou, Zheng; Kelley, Richard L.; Jia, Songtao

2017-01-01

The fidelity of epigenetic inheritance or, the precision by which epigenetic information is passed along, is an essential parameter for measuring the effectiveness of the process. How the precision of the process is achieved or modulated, however, remains largely elusive. We have performed quantitative measurement of epigenetic fidelity, using position effect variegation (PEV) in Schizosaccharomyces pombe as readout, to explore whether replication perturbation affects nucleosome-mediated epigenetic inheritance. We show that replication stresses, due to either hydroxyurea treatment or various forms of genetic lesions of the replication machinery, reduce the inheritance accuracy of CENP-A/Cnp1 nucleosome positioning within centromere. Mechanistically, we demonstrate that excessive formation of single-stranded DNA, a common molecular abnormality under these conditions, might have correlation with the reduction in fidelity of centromeric chromatin duplication. Furthermore, we show that replication stress broadly changes chromatin structure at various loci in the genome, such as telomere heterochromatin expanding and mating type locus heterochromatin spreading out of the boundaries. Interestingly, the levels of inheritable expanding at sub-telomeric heterochromatin regions are highly variable among independent cell populations. Finally, we show that HU treatment of the multi-cellular organisms C. elegans and D. melanogaster affects epigenetically programmed development and PEV, illustrating the evolutionary conservation of the phenomenon. Replication stress, in addition to its demonstrated role in genetic instability, promotes variable epigenetic instability throughout the epigenome. PMID:28749973

An ecological alternative to Snodgrass & Vanderwart: 360 high quality colour images with norms for seven psycholinguistic variables.

PubMed

Moreno-Martínez, Francisco Javier; Montoro, Pedro R

2012-01-01

This work presents a new set of 360 high quality colour images belonging to 23 semantic subcategories. Two hundred and thirty-six Spanish speakers named the items and also provided data from seven relevant psycholinguistic variables: age of acquisition, familiarity, manipulability, name agreement, typicality and visual complexity. Furthermore, we also present lexical frequency data derived from Internet search hits. Apart from the high number of variables evaluated, knowing that it affects the processing of stimuli, this new set presents important advantages over other similar image corpi: (a) this corpus presents a broad number of subcategories and images; for example, this will permit researchers to select stimuli of appropriate difficulty as required, (e.g., to deal with problems derived from ceiling effects); (b) the fact of using coloured stimuli provides a more realistic, ecologically-valid, representation of real life objects. In sum, this set of stimuli provides a useful tool for research on visual object- and word-processing, both in neurological patients and in healthy controls.

Flow, affect and visual creativity.

PubMed

Cseh, Genevieve M; Phillips, Louise H; Pearson, David G

2015-01-01

Flow (being in the zone) is purported to have positive consequences in terms of affect and performance; however, there is no empirical evidence about these links in visual creativity. Positive affect often--but inconsistently--facilitates creativity, and both may be linked to experiencing flow. This study aimed to determine relationships between these variables within visual creativity. Participants performed the creative mental synthesis task to simulate the creative process. Affect change (pre- vs. post-task) and flow were measured via questionnaires. The creativity of synthesis drawings was rated objectively and subjectively by judges. Findings empirically demonstrate that flow is related to affect improvement during visual creativity. Affect change was linked to productivity and self-rated creativity, but no other objective or subjective performance measures. Flow was unrelated to all external performance measures but was highly correlated with self-rated creativity; flow may therefore motivate perseverance towards eventual excellence rather than provide direct cognitive enhancement.

The Cox proportional Hazard model on duration of birth process

NASA Astrophysics Data System (ADS)

Wuryandari, Triastuti; Haryatmi Kartiko, Sri; Danardono

2018-05-01

The duration of birth process, which is measured from the birth sign until baby born, is one important factor to the whole outcome of delivery process. There is a method of birth process that given relaxing and gentle treatment to the mother caled as gentlebirth. Gentlebirth is a method of birth process that combines brain science, birth science and technology to empower positive birth without pain. However the effect of method to the duration of birth process is still need empirical investigations. Therefore, the objective of this paper is to analyze the duration of birth process using the appropriate statistical methods for durational data, survival data or time to event data. Since there are many variables or factor that may affect the duration, a regression model is considerated. The flexibility of the Cox Proportional Hazard Model in the sense that there is no distributional assumption required, makes the Cox Model as the appropriate model and method to analyze the duration birth process. It is concluded that the Gentlebirth method affects on duration of birth process, with Hazard Ratio of 2.073, showing that the duration of birth process with gentlebirth method is faster than the other method.

Sleep and mental disorders: A meta-analysis of polysomnographic research.

PubMed

Baglioni, Chiara; Nanovska, Svetoslava; Regen, Wolfram; Spiegelhalder, Kai; Feige, Bernd; Nissen, Christoph; Reynolds, Charles F; Riemann, Dieter

2016-09-01

Investigating sleep in mental disorders has the potential to reveal both disorder-specific and transdiagnostic psychophysiological mechanisms. This meta-analysis aimed at determining the polysomnographic (PSG) characteristics of several mental disorders. Relevant studies were searched through standard strategies. Controlled PSG studies evaluating sleep in affective, anxiety, eating, pervasive developmental, borderline and antisocial personality disorders, attention-deficit-hyperactivity disorder (ADHD), and schizophrenia were included. PSG variables of sleep continuity, depth, and architecture, as well as rapid-eye movement (REM) sleep were considered. Calculations were performed with the "Comprehensive Meta-Analysis" and "R" software. Using random effects modeling, for each disorder and each variable, a separate meta-analysis was conducted if at least 3 studies were available for calculation of effect sizes as standardized means (Hedges' g). Sources of variability, that is, sex, age, and mental disorders comorbidity, were evaluated in subgroup analyses. Sleep alterations were evidenced in all disorders, with the exception of ADHD and seasonal affective disorders. Sleep continuity problems were observed in most mental disorders. Sleep depth and REM pressure alterations were associated with affective, anxiety, autism and schizophrenia disorders. Comorbidity was associated with enhanced REM sleep pressure and more inhibition of sleep depth. No sleep parameter was exclusively altered in 1 condition; however, no 2 conditions shared the same PSG profile. Sleep continuity disturbances imply a transdiagnostic imbalance in the arousal system likely representing a basic dimension of mental health. Sleep depth and REM variables might play a key role in psychiatric comorbidity processes. Constellations of sleep alterations may define distinct disorders better than alterations in 1 single variable. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

A process dissociation approach to objective-projective test score interrelationships.

PubMed

Bornstein, Robert F

2002-02-01

Even when self-report and projective measures of a given trait or motive both predict theoretically related features of behavior, scores on the 2 tests correlate modestly with each other. This article describes a process dissociation framework for personality assessment, derived from research on implicit memory and learning, which can resolve these ostensibly conflicting results. Research on interpersonal dependency is used to illustrate 3 key steps in the process dissociation approach: (a) converging behavioral predictions, (b) modest test score intercorrelations, and (c) delineation of variables that differentially affect self-report and projective test scores. Implications of the process dissociation framework for personality assessment and test development are discussed.

Intraseasonal and interannual oscillations in coupled ocean-atmosphere models

NASA Technical Reports Server (NTRS)

Hirst, Anthony C.; Lau, K.-M.

1990-01-01

An investigation is presented of coupled ocean-atmosphere models' behavior in an environment where atmospheric wave speeds are substantially reduced from dry atmospheric values by such processes as condensation-moisture convergence. Modes are calculated for zonally periodic, unbounded ocean-atmosphere systems, emphasizing the importance of an inclusion of prognostic atmosphere equations in simple coupled ocean-atmosphere models with a view to simulations of intraseasonal variability and its possible interaction with interannual variability. The dynamics of low and high frequency modes are compared; both classes are sensitive to the degree to which surface wind anomalies are able to affect the evaporation rate.

A MODEL FOR (QUASI-)PERIODIC MULTIWAVELENGTH PHOTOMETRIC VARIABILITY IN YOUNG STELLAR OBJECTS

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

Kesseli, Aurora Y.; Petkova, Maya A.; Wood, Kenneth

We present radiation transfer models of rotating young stellar objects (YSOs) with hot spots in their atmospheres, inner disk warps, and other three-dimensional effects in the nearby circumstellar environment. Our models are based on the geometry expected from magneto-accretion theory, where material moving inward in the disk flows along magnetic field lines to the star and creates stellar hot spots upon impact. Due to rotation of the star and magnetosphere, the disk is variably illuminated. We compare our model light curves to data from the Spitzer YSOVAR project to determine if these processes can explain the variability observed at opticalmore » and mid-infrared wavelengths in young stars. We focus on those variables exhibiting “dipper” behavior that may be periodic, quasi-periodic, or aperiodic. We find that the stellar hot-spot size and temperature affects the optical and near-infrared light curves, while the shape and vertical extent of the inner disk warp affects the mid-IR light curve variations. Clumpy disk distributions with non-uniform fractal density structure produce more stochastic light curves. We conclude that magneto-accretion theory is consistent with certain aspects of the multiwavelength photometric variability exhibited by low-mass YSOs. More detailed modeling of individual sources can be used to better determine the stellar hot-spot and inner disk geometries of particular sources.« less

The Role of Emotion in Global Warming Policy Support and Opposition

PubMed Central

Smith, Nicholas; Leiserowitz, Anthony

2014-01-01

Prior research has found that affect and affective imagery strongly influence public support for global warming. This article extends this literature by exploring the separate influence of discrete emotions. Utilizing a nationally representative survey in the United States, this study found that discrete emotions were stronger predictors of global warming policy support than cultural worldviews, negative affect, image associations, or sociodemographic variables. In particular, worry, interest, and hope were strongly associated with increased policy support. The results contribute to experiential theories of risk information processing and suggest that discrete emotions play a significant role in public support for climate change policy. Implications for climate change communication are also discussed. PMID:24219420

The role of emotion in global warming policy support and opposition.

PubMed

Smith, Nicholas; Leiserowitz, Anthony

2014-05-01

Prior research has found that affect and affective imagery strongly influence public support for global warming. This article extends this literature by exploring the separate influence of discrete emotions. Utilizing a nationally representative survey in the United States, this study found that discrete emotions were stronger predictors of global warming policy support than cultural worldviews, negative affect, image associations, or sociodemographic variables. In particular, worry, interest, and hope were strongly associated with increased policy support. The results contribute to experiential theories of risk information processing and suggest that discrete emotions play a significant role in public support for climate change policy. Implications for climate change communication are also discussed. © 2013 Society for Risk Analysis.

Auditory agnosia.

PubMed

Slevc, L Robert; Shell, Alison R

2015-01-01

Auditory agnosia refers to impairments in sound perception and identification despite intact hearing, cognitive functioning, and language abilities (reading, writing, and speaking). Auditory agnosia can be general, affecting all types of sound perception, or can be (relatively) specific to a particular domain. Verbal auditory agnosia (also known as (pure) word deafness) refers to deficits specific to speech processing, environmental sound agnosia refers to difficulties confined to non-speech environmental sounds, and amusia refers to deficits confined to music. These deficits can be apperceptive, affecting basic perceptual processes, or associative, affecting the relation of a perceived auditory object to its meaning. This chapter discusses what is known about the behavioral symptoms and lesion correlates of these different types of auditory agnosia (focusing especially on verbal auditory agnosia), evidence for the role of a rapid temporal processing deficit in some aspects of auditory agnosia, and the few attempts to treat the perceptual deficits associated with auditory agnosia. A clear picture of auditory agnosia has been slow to emerge, hampered by the considerable heterogeneity in behavioral deficits, associated brain damage, and variable assessments across cases. Despite this lack of clarity, these striking deficits in complex sound processing continue to inform our understanding of auditory perception and cognition. © 2015 Elsevier B.V. All rights reserved.

Constant negotiating: managing work-related musculoskeletal disorders while remaining at the workplace.

PubMed

Smith-Young, Joanne; Solberg, Shirley; Gaudine, Alice

2014-02-01

We used grounded theory to explore processes and strategies used by workers affected by work-related musculoskeletal disorders (WMSDs) while they remained in the workplace, and we developed a theory to describe the overall process. Participants included 25 workers affected by WMSDs who were currently employed in various workplaces in Newfoundland and Labrador, Canada. The theoretical model has five main phases: (a) becoming concerned, (b) getting medical help, (c) dealing with the workplace, (d) making adjustments to lifestyle, and (e) taking charge, each with separate subphases. Constant negotiating was the core variable that explained the overall process, with workers engaged in negotiations with others in occupational, health, and social contexts. Using a two-dimensional figure, we illustrate the negotiation strategies workers used. We discuss implications for health care, workplaces, education, and research for creating a culture of understanding and respect for injured workers who wish to remain working after developing WMSDs.

Switching between simple cognitive tasks: the interaction of top-down and bottom-up factors

NASA Technical Reports Server (NTRS)

Ruthruff, E.; Remington, R. W.; Johnston, J. C.

2001-01-01

How do top-down factors (e.g., task expectancy) and bottom-up factors (e.g., task recency) interact to produce an overall level of task readiness? This question was addressed by factorially manipulating task expectancy and task repetition in a task-switching paradigm. The effects of expectancy and repetition on response time tended to interact underadditively, but only because the traditional binary task-repetition variable lumps together all switch trials, ignoring variation in task lag. When the task-recency variable was scaled continuously, all 4 experiments instead showed additivity between expectancy and recency. The results indicated that expectancy and recency influence different stages of mental processing. One specific possibility (the configuration-execution model) is that task expectancy affects the time required to configure upcoming central operations, whereas task recency affects the time required to actually execute those central operations.

Noonan syndrome and clinically related disorders

PubMed Central

Tartaglia, Marco; Gelb, Bruce D.; Zenker, Martin

2010-01-01

Noonan syndrome is a relatively common, clinically variable developmental disorder. Cardinal features include postnatally reduced growth, distinctive facial dysmorphism, congenital heart defects and hypertrophic cardiomyopathy, variable cognitive deficit and skeletal, ectodermal and hematologic anomalies. Noonan syndrome is transmitted as an autosomal dominant trait, and is genetically heterogeneous. So far, heterozygous mutations in nine genes (PTPN11, SOS1, KRAS, NRAS, RAF1, BRAF, SHOC2, MEK1 and CBL) have been documented to underlie this disorder or clinically related phenotypes. Based on these recent discoveries, the diagnosis can now be confirmed molecularly in approximately 75% of affected individuals. Affected genes encode for proteins participating in the RAS-mitogen-activated protein kinases (MAPK) signal transduction pathway, which is implicated in several developmental processes controlling morphology determination, organogenesis, synaptic plasticity and growth. Here, we provide an overview of clinical aspects of this disorder and closely related conditions, the molecular mechanisms underlying pathogenesis, and major genotype-phenotype correlations. PMID:21396583

Contextualization: Memory Formation and Retrieval in a Nested Environment

NASA Astrophysics Data System (ADS)

Piefke, Martina; Markowitsch, Hans J.

Episodic memory functions are highly context-dependent. This is true for both experimental and autobiographical episodic memory. We here review neuropsychological and neuroimaging evidence for effects of differential encoding and retrieval contexts on episodic memory performance as well as the underlying neurofunctional mechanisms. In studies of laboratory episodic memory, the influence of context parameters can be assessed by experimental manipulations. Such experiments suggest that contextual variables mainly affect prefrontal functions supporting executive processes involved in episodic learning and retrieval. Context parameters affecting episodic autobiographical memory are far more complex and cannot easily be controlled. Data support the view that not only prefrontal, but also further medial temporal and posterior parietal regions mediating the re-experience and emotional evaluation of personal memories are highly influenced by changing contextual variables of memory encoding and retrieval. Based on our review of available data, we thus suggest that experimental and autobiographical episodic memories are influenced by both overlapping and differential context parameters.

Interannual rainfall variability and SOM-based circulation classification

NASA Astrophysics Data System (ADS)

Wolski, Piotr; Jack, Christopher; Tadross, Mark; van Aardenne, Lisa; Lennard, Christopher

2018-01-01

Self-Organizing Maps (SOM) based classifications of synoptic circulation patterns are increasingly being used to interpret large-scale drivers of local climate variability, and as part of statistical downscaling methodologies. These applications rely on a basic premise of synoptic climatology, i.e. that local weather is conditioned by the large-scale circulation. While it is clear that this relationship holds in principle, the implications of its implementation through SOM-based classification, particularly at interannual and longer time scales, are not well recognized. Here we use a SOM to understand the interannual synoptic drivers of climate variability at two locations in the winter and summer rainfall regimes of South Africa. We quantify the portion of variance in seasonal rainfall totals that is explained by year to year differences in the synoptic circulation, as schematized by a SOM. We furthermore test how different spatial domain sizes and synoptic variables affect the ability of the SOM to capture the dominant synoptic drivers of interannual rainfall variability. Additionally, we identify systematic synoptic forcing that is not captured by the SOM classification. The results indicate that the frequency of synoptic states, as schematized by a relatively disaggregated SOM (7 × 9) of prognostic atmospheric variables, including specific humidity, air temperature and geostrophic winds, captures only 20-45% of interannual local rainfall variability, and that the residual variance contains a strong systematic component. Utilising a multivariate linear regression framework demonstrates that this residual variance can largely be explained using synoptic variables over a particular location; even though they are used in the development of the SOM their influence, however, diminishes with the size of the SOM spatial domain. The influence of the SOM domain size, the choice of SOM atmospheric variables and grid-point explanatory variables on the levels of explained variance, is consistent with the general understanding of the dominant processes and atmospheric variables that affect rainfall variability at a particular location.

Plot-scale field experiment of surface hydrologic processes with EOS implications

NASA Technical Reports Server (NTRS)

Laymon, Charles A.; Macari, Emir J.; Costes, Nicholas C.

1992-01-01

Plot-scale hydrologic field studies were initiated at NASA Marshall Space Flight Center to a) investigate the spatial and temporal variability of surface and subsurface hydrologic processes, particularly as affected by vegetation, and b) develop experimental techniques and associated instrumentation methodology to study hydrologic processes at increasingly large spatial scales. About 150 instruments, most of which are remotely operated, have been installed at the field site to monitor ground atmospheric conditions, precipitation, interception, soil-water status, and energy flux. This paper describes the nature of the field experiment, instrumentation and sampling rationale, and presents preliminary findings.

PROCESS DEVELOPMENT QUARTERLY REPORT. II. PILOT PLANT WORK

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

Kuhlman, N. ed.

1957-05-01

Progress is reported on the gross solubility of U in digestions of Mallinokrodt feed materials, studies of variables affecting U purity in a TBP hexane extraction cycle, low-acid flowsheet for TBP--hexane extraction process based on a 440 g U/liter in lM HNO/sub 3/ digest liquor, hacking studies in the pilot plant pumperdecanter system, recovery of U from residues from the dingot process, lowering the H level in dingot metal, forging of dingot bar stock, dingot extrusion, fubrication of UO/sub 2/ fuel elements, and the determination of H content of derby and ingot metal. (W.L.H.)

The growth receptors and their role in wound healing.

PubMed

Rolfe, Kerstin J; Grobbelaar, Adriaan O

2010-11-01

Abnormal wound healing is a major problem in healthcare today, with both scarring and chronic wounds affecting large numbers of individuals worldwide. Wound healing is a complex process involving several variables, including growth factors and their receptors. Chronic wounds fail to complete the wound healing process, while scarring is considered to be an overzealous wound healing process. Growth factor receptors and their ligands are being investigated to assess their potential in the development of therapeutic strategies to improve wound healing. This review discusses potential therapeutics for manipulating growth factors and their corresponding receptors for the treatment of abnormal wound healing.

Affective touch awareness in mental health and disease relates to autistic traits - An explorative neurophysiological investigation.

PubMed

Croy, Ilona; Geide, Helen; Paulus, Martin; Weidner, Kerstin; Olausson, Håkan

2016-11-30

Affective touch is important for social interaction within families and groups and there is evidence that unmyelinated C tactile fibers are involved in this process. Individuals with autism spectrum disorders show alterations in the perception and processing of affective touch. sThus, we hypothesized that affective touch awareness based on C tactile fiber activation is impaired in individuals with high levels of autistic trait. The pleasantness perception of optimal and suboptimal C tactile stimuli was tested in an explorative study in 70 patients recruited from an outpatient psychotherapy clinic and 69 healthy comparison subjects. All participants completed questionnaires about autistic traits, depressive symptomatology, childhood maltreatment, and about the daily amount of touch. Relative to comparison subjects, patients reported engaging in touch less frequently in daily life and rated touch less pleasant. Reduced valence ratings of touch were explained by childhood maltreatment but not by any particular disorder or depression severity. Among all tested variables, the affective touch awareness correlated with autistic traits only - in patients as well as in comparison subjects. Taken together, individuals with mental health issues have a lower baseline of expression and reception of affective touch. Autistic traits and childhood maltreatment modulate the experience of affective touch. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Point process analyses of variations in smoking rate by setting, mood, gender, and dependence

PubMed Central

Shiffman, Saul; Rathbun, Stephen L.

2010-01-01

The immediate emotional and situational antecedents of ad libitum smoking are still not well understood. We re-analyzed data from Ecological Momentary Assessment using novel point-process analyses, to assess how craving, mood, and social setting influence smoking rate, as well as assessing the moderating effects of gender and nicotine dependence. 304 smokers recorded craving, mood, and social setting using electronic diaries when smoking and at random nonsmoking times over 16 days of smoking. Point-process analysis, which makes use of the known random sampling scheme for momentary variables, examined main effects of setting and interactions with gender and dependence. Increased craving was associated with higher rates of smoking, particularly among women. Negative affect was not associated with smoking rate, even in interaction with arousal, but restlessness was associated with substantially higher smoking rates. Women's smoking tended to be less affected by negative affect. Nicotine dependence had little moderating effect on situational influences. Smoking rates were higher when smokers were alone or with others smoking, and smoking restrictions reduced smoking rates. However, the presence of others smoking undermined the effects of restrictions. The more sensitive point-process analyses confirmed earlier findings, including the surprising conclusion that negative affect by itself was not related to smoking rates. Contrary to hypothesis, men's and not women's smoking was influenced by negative affect. Both smoking restrictions and the presence of others who are not smoking suppress smoking, but others’ smoking undermines the effects of restrictions. Point-process analyses of EMA data can bring out even small influences on smoking rate. PMID:21480683

A data mining approach to optimize pellets manufacturing process based on a decision tree algorithm.

PubMed

Ronowicz, Joanna; Thommes, Markus; Kleinebudde, Peter; Krysiński, Jerzy

2015-06-20

The present study is focused on the thorough analysis of cause-effect relationships between pellet formulation characteristics (pellet composition as well as process parameters) and the selected quality attribute of the final product. The shape using the aspect ratio value expressed the quality of pellets. A data matrix for chemometric analysis consisted of 224 pellet formulations performed by means of eight different active pharmaceutical ingredients and several various excipients, using different extrusion/spheronization process conditions. The data set contained 14 input variables (both formulation and process variables) and one output variable (pellet aspect ratio). A tree regression algorithm consistent with the Quality by Design concept was applied to obtain deeper understanding and knowledge of formulation and process parameters affecting the final pellet sphericity. The clear interpretable set of decision rules were generated. The spehronization speed, spheronization time, number of holes and water content of extrudate have been recognized as the key factors influencing pellet aspect ratio. The most spherical pellets were achieved by using a large number of holes during extrusion, a high spheronizer speed and longer time of spheronization. The described data mining approach enhances knowledge about pelletization process and simultaneously facilitates searching for the optimal process conditions which are necessary to achieve ideal spherical pellets, resulting in good flow characteristics. This data mining approach can be taken into consideration by industrial formulation scientists to support rational decision making in the field of pellets technology. Copyright © 2015 Elsevier B.V. All rights reserved.

Additive Manufacturing in Production: A Study Case Applying Technical Requirements

NASA Astrophysics Data System (ADS)

Ituarte, Iñigo Flores; Coatanea, Eric; Salmi, Mika; Tuomi, Jukka; Partanen, Jouni

Additive manufacturing (AM) is expanding the manufacturing capabilities. However, quality of AM produced parts is dependent on a number of machine, geometry and process parameters. The variability of these parameters affects the manufacturing drastically and therefore standardized processes and harmonized methodologies need to be developed to characterize the technology for end use applications and enable the technology for manufacturing. This research proposes a composite methodology integrating Taguchi Design of Experiments, multi-objective optimization and statistical process control, to optimize the manufacturing process and fulfil multiple requirements imposed to an arbitrary geometry. The proposed methodology aims to characterize AM technology depending upon manufacturing process variables as well as to perform a comparative assessment of three AM technologies (Selective Laser Sintering, Laser Stereolithography and Polyjet). Results indicate that only one machine, laser-based Stereolithography, was feasible to fulfil simultaneously macro and micro level geometrical requirements but mechanical properties were not at required level. Future research will study a single AM system at the time to characterize AM machine technical capabilities and stimulate pre-normative initiatives of the technology for end use applications.

Development and validation of a predictive model for the influences of selected product and process variables on ascorbic acid degradation in simulated fruit juice.

PubMed

Gabriel, Alonzo A; Cayabyab, Jochelle Elysse C; Tan, Athalie Kaye L; Corook, Mark Lester F; Ables, Errol John O; Tiangson-Bayaga, Cecile Leah P

2015-06-15

A predictive response surface model for the influences of product (soluble solids and titratable acidity) and process (temperature and heating time) parameters on the degradation of ascorbic acid (AA) in heated simulated fruit juices (SFJs) was established. Physicochemical property ranges of freshly squeezed and processed juices, and a previously established decimal reduction times of Escherichiacoli O157:H7 at different heating temperatures were used in establishing a Central Composite Design of Experiment that determined the combinations of product and process variable used in the model building. Only the individual linear effects of temperature and heating time significantly (P<0.05) affected AA reduction (%AAr). Validating systems either over- or underestimated actual %AAr with bias factors 0.80-1.20. However, all validating systems still resulted in acceptable predictive efficacy, with accuracy factor 1.00-1.26. The model may be useful in establishing unique process schedules for specific products, for the simultaneous control and improvement of food safety and quality. Copyright © 2015 Elsevier Ltd. All rights reserved.

Students' Interpersonal Trust and Attitudes towards Standardised Tests: Exploring Affective Variables Related to Student Assessment

ERIC Educational Resources Information Center

Chu, Man-Wai; Guo, Qi; Leighton, Jacqueline P.

2014-01-01

Cognitive and psychometric variables have directed research on student test performance. However, student learning involves a substantial affective component. The objective of this study was to explore the relationship between two kinds of affective variables--interpersonal trust and attitudes towards standardised tests--likely to underlie student…

Intersubject Variability in Fearful Face Processing: The Link Between Behavior and Neural Activation

PubMed Central

Doty, Tracy J.; Japee, Shruti; Ingvar, Martin; Ungerleider, Leslie G.

2014-01-01

Stimuli that signal threat show considerable variability in the extent to which they enhance behavior, even among healthy individuals. However, the neural underpinning of this behavioral variability is not well understood. By manipulating expectation of threat in an fMRI study of fearful vs. neutral face categorization, we uncovered a network of areas underlying variability in threat processing in healthy adults. We explicitly altered expectation by presenting face images at three different expectation levels: 80%, 50%, and 20%. Subjects were instructed to report as fast and as accurately as possible whether the face was fearful (signaled threat) or not. An uninformative cue preceded each face by 4 seconds (s). By taking the difference between response times (RT) to fearful compared to neutral faces, we quantified an overall fear RT bias (i.e. faster to fearful than neutral faces) for each subject. This bias correlated positively with late trial fMRI activation (8 s after the face) during unexpected fearful face trials in bilateral ventromedial prefrontal cortex, the left subgenual cingulate cortex, and the right caudate nucleus and correlated negatively with early trial fMRI activation (4 s after the cue) during expected neutral face trials in bilateral dorsal striatum and the right ventral striatum. These results demonstrate that the variability in threat processing among healthy adults is reflected not only in behavior but also in the magnitude of activation in medial prefrontal and striatal regions that appear to encode affective value. PMID:24841078

An Overview of OCTAV-UTLS (Observed Composition Trends and Variability in the UTLS), a SPARC Emerging Activity

NASA Astrophysics Data System (ADS)

Petropavlovskikh, I. V.; Manney, G. L.; Hoor, P. M.; Bourassa, A. E.; Braathen, G.; Chang, K. L.; Hegglin, M. I.; Kramarova, N. A.; Kunkel, D.; Lawrence, Z. D.; Leblanc, T.; Livesey, N. J.; Millan Valle, L. F.; Stiller, G. P.; Tegtmeier, S.; Thouret, V.; Voigt, C.; Walker, K. A.

2017-12-01

The distribution of tracers in the upper troposphere and lower stratosphere (UTLS) shows large spatial and temporal variability because of interactions of transport, chemical, and mixing processes near the tropopause, as well as variations in the location of the tropopause itself. This strongly affects quantitative estimates of the impact of radiatively active substances, including ozone and water vapour, on surface temperatures, and complicates diagnosis of dynamical processes such as stratosphere troposphere exchange (STE). The Stratosphere-troposphere Processes And their Role in Climate (SPARC) emerging activity OCTAV-UTLS (Observed Composition Trends and Variability in the UTLS) aims to reduce the uncertainties in trend estimates by accounting for these dynamically induced sources of variability. Achieving these goals by using existing UTLS trace gas observations from aircraft, ground-based, balloon and satellite platforms requires a consistent analysis of these different data with respect to the tropopause or the jets. As a central task for OCTAV-UTLS, we are developing and applying common metrics, calculated using the same reanalysis datasets, to compare UTLS data using geophysically-based coordinate systems including tropopause and upper tropospheric jet relative coordinates. In addition to assessing present day measurement capabilities, OCTAV-UTLS will assess gaps in current geographical / temporal sampling of the UTLS that limit our ability to determine atmospheric composition variability and trends. This talk will provide an overview of the OCTAV-UTLS activity and some examples of initial calculations of geophysically-based coordinates and comparisons of remapped data.

Intersubject variability in fearful face processing: the link between behavior and neural activation.

PubMed

Doty, Tracy J; Japee, Shruti; Ingvar, Martin; Ungerleider, Leslie G

2014-12-01

Stimuli that signal threat show considerable variability in the extents to which they enhance behavior, even among healthy individuals. However, the neural underpinning of this behavioral variability is not well understood. By manipulating expectation of threat in an fMRI study of fearful versus neutral face categorization, we uncovered a network of areas underlying variability in threat processing in healthy adults. We explicitly altered expectations by presenting face images at three different expectation levels: 80 %, 50 %, and 20 %. Subjects were instructed to report as quickly and accurately as possible whether the face was fearful (signaled threat) or not. An uninformative cue preceded each face by 4 s. By taking the difference between reaction times (RTs) to fearful and neutral faces, we quantified an overall fear RT bias (i.e., faster to fearful than to neutral faces) for each subject. This bias correlated positively with late-trial fMRI activation (8 s after the face) during unexpected-fearful-face trials in bilateral ventromedial prefrontal cortex, the left subgenual cingulate cortex, and the right caudate nucleus, and correlated negatively with early-trial fMRI activation (4 s after the cue) during expected-neutral-face trials in bilateral dorsal striatum and the right ventral striatum. These results demonstrate that the variability in threat processing among healthy adults is reflected not only in behavior, but also in the magnitude of activation in medial prefrontal and striatal regions that appear to encode affective value.

Associations between cognitive and gait performance during single- and dual-task walking in people with Parkinson disease.

PubMed

Stegemöller, Elizabeth L; Wilson, Jonathan P; Hazamy, Audrey; Shelley, Mack C; Okun, Michael S; Altmann, Lori J P; Hass, Chris J

2014-06-01

Cognitive impairments in Parkinson disease (PD) manifest as deficits in speed of processing, working memory, and executive function and attention abilities. The gait impairment in PD is well documented to include reduced speed, shortened step lengths, and increased step-to-step variability. However, there is a paucity of research examining the relationship between overground walking and cognitive performance in people with PD. This study sought to examine the relationship between both the mean and variability of gait spatiotemporal parameters and cognitive performance across a broad range of cognitive domains. A cross-sectional design was used. Thirty-five participants with no dementia and diagnosed with idiopathic PD completed a battery of 12 cognitive tests that yielded 3 orthogonal factors: processing speed, working memory, and executive function and attention. Participants completed 10 trials of overground walking (single-task walking) and 5 trials of overground walking while counting backward by 3's (dual-task walking). All gait measures were impaired by the dual task. Cognitive processing speed correlated with stride length and walking speed. Executive function correlated with step width variability. There were no significant associations with working memory. Regression models relating speed of processing to gait spatiotemporal variables revealed that including dual-task costs in the model significantly improved the fit of the model. Participants with PD were tested only in the on-medication state. Different characteristics of gait are related to distinct types of cognitive processing, which may be differentially affected by dual-task walking due to the pathology of PD. © 2014 American Physical Therapy Association.

The Heterogeneity in Retrieved Relations between the Personality Trait ‘Harm Avoidance’ and Gray Matter Volumes Due to Variations in the VBM and ROI Labeling Processing Settings

PubMed Central

Van Schuerbeek, Peter; Baeken, Chris; De Mey, Johan

2016-01-01

Concerns are raising about the large variability in reported correlations between gray matter morphology and affective personality traits as ‘Harm Avoidance’ (HA). A recent review study (Mincic 2015) stipulated that this variability could come from methodological differences between studies. In order to achieve more robust results by standardizing the data processing procedure, as a first step, we repeatedly analyzed data from healthy females while changing the processing settings (voxel-based morphology (VBM) or region-of-interest (ROI) labeling, smoothing filter width, nuisance parameters included in the regression model, brain atlas and multiple comparisons correction method). The heterogeneity in the obtained results clearly illustrate the dependency of the study outcome to the opted analysis settings. Based on our results and the existing literature, we recommended the use of VBM over ROI labeling for whole brain analyses with a small or intermediate smoothing filter (5-8mm) and a model variable selection step included in the processing procedure. Additionally, it is recommended that ROI labeling should only be used in combination with a clear hypothesis and that authors are encouraged to report their results uncorrected for multiple comparisons as supplementary material to aid review studies. PMID:27096608

Kpejigaou: an indigenous, high-protein, low-fat, cowpea-based griddled food proposed for coastal West Africa.

PubMed

Amonsou, Eric Oscar; Sakyi-Dawson, Esther; Saalia, Firibu Kwesi; Houssou, Paul

2008-12-01

Griddled cowpea paste foods have high nutritional potential because they are low in fat but high in protein. A good understanding of process and product characteristics of kpejigaou is necessary to improve its quality and enhance acceptability. To describe the product, evaluate critical variables in traditional processing, and determine consumer quality criteria and preferences for kpejigaou. A survey of kpejigaou processing was carried out among processors and regular consumers of kpejigaou. Kpejigaou is flat and circular in shape, with uniform thickness and porous structure. The production process of kpejigaou was found to be simple and rapid, but the quality of the finished product varied among processors and among batches. Critical processing variables affecting quality were dehulling of the cowpeas, type of griddling equipment, and griddling temperature. Texture (sponginess) is the most important quality index that determines the preference and acceptability of kpejigaou by consumers. Traditionally processed kpejigaou does not meet current standards for high-quality foods. This study provides the basis for efforts to standardize the kpejigaou process to ensure consistent product quality and enhance the acceptability of kpejigaou among consumers. Kpejigaou has a potential for success if marketed as a low-fat, nutritious fast food.

Epigenetic modification of the oxytocin receptor gene influences the perception of anger and fear in the human brain

PubMed Central

Puglia, Meghan H.; Lillard, Travis S.; Morris, James P.; Connelly, Jessica J.

2015-01-01

In humans, the neuropeptide oxytocin plays a critical role in social and emotional behavior. The actions of this molecule are dependent on a protein that acts as its receptor, which is encoded by the oxytocin receptor gene (OXTR). DNA methylation of OXTR, an epigenetic modification, directly influences gene transcription and is variable in humans. However, the impact of this variability on specific social behaviors is unknown. We hypothesized that variability in OXTR methylation impacts social perceptual processes often linked with oxytocin, such as perception of facial emotions. Using an imaging epigenetic approach, we established a relationship between OXTR methylation and neural activity in response to emotional face processing. Specifically, high levels of OXTR methylation were associated with greater amounts of activity in regions associated with face and emotion processing including amygdala, fusiform, and insula. Importantly, we found that these higher levels of OXTR methylation were also associated with decreased functional coupling of amygdala with regions involved in affect appraisal and emotion regulation. These data indicate that the human endogenous oxytocin system is involved in attenuation of the fear response, corroborating research implicating intranasal oxytocin in the same processes. Our findings highlight the importance of including epigenetic mechanisms in the description of the endogenous oxytocin system and further support a central role for oxytocin in social cognition. This approach linking epigenetic variability with neural endophenotypes may broadly explain individual differences in phenotype including susceptibility or resilience to disease. PMID:25675509

Eye Contact Affects Object Representation in 9-Month-Old Infants.

PubMed

Okumura, Yuko; Kobayashi, Tessei; Itakura, Shoji

2016-01-01

Social cues in interaction with others enable infants to extract useful information from their environment. Although previous research has shown that infants process and retain different information about an object depending on the presence of social cues, the effect of eye contact as an isolated independent variable has not been investigated. The present study investigated how eye contact affects infants' object processing. Nine-month-olds engaged in two types of social interactions with an experimenter. When the experimenter showed an object without eye contact, the infants processed and remembered both the object's location and its identity. In contrast, when the experimenter showed the object while making eye contact with the infant, the infant preferentially processed object's identity but not its location. Such effects might assist infants to selectively attend to useful information. Our findings revealed that 9-month-olds' object representations are modulated in accordance with the context, thus elucidating the function of eye contact for infants' object representation.

A systematic approach to evaluate parameter consistency in the inlet stream of source separated biowaste composting facilities: A case study in Colombia.

PubMed

Oviedo-Ocaña, E R; Torres-Lozada, P; Marmolejo-Rebellon, L F; Torres-López, W A; Dominguez, I; Komilis, D; Sánchez, A

2017-04-01

Biowaste is commonly the largest fraction of municipal solid waste (MSW) in developing countries. Although composting is an effective method to treat source separated biowaste (SSB), there are certain limitations in terms of operation, partly due to insufficient control to the variability of SSB quality, which affects process kinetics and product quality. This study assesses the variability of the SSB physicochemical quality in a composting facility located in a small town of Colombia, in which SSB collection was performed twice a week. Likewise, the influence of the SSB physicochemical variability on the variability of compost parameters was assessed. Parametric and non-parametric tests (i.e. Student's t-test and the Mann-Whitney test) showed no significant differences in the quality parameters of SSB among collection days, and therefore, it was unnecessary to establish specific operation and maintenance regulations for each collection day. Significant variability was found in eight of the twelve quality parameters analyzed in the inlet stream, with corresponding coefficients of variation (CV) higher than 23%. The CVs for the eight parameters analyzed in the final compost (i.e. pH, moisture, total organic carbon, total nitrogen, C/N ratio, total phosphorus, total potassium and ash) ranged from 9.6% to 49.4%, with significant variations in five of those parameters (CV>20%). The above indicate that variability in the inlet stream can affect the variability of the end-product. Results suggest the need to consider variability of the inlet stream in the performance of composting facilities to achieve a compost of consistent quality. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Change Process at Schools Based on the Variables of School Administrators and Environment

ERIC Educational Resources Information Center

Balikçi, Abdullah; Akbasli, Sait; Sahin, Mehmet; Kiliç, Murat

2017-01-01

Change is a growing phenomenon in the era we live. The issue of change has been one of the topics of interest in the field of administration. In general, change refers to transfer from the present situation to another situation and differentiation. Implementations related to the change also affect today's education systems. School administrators,…

Strong spatial variability in trace gas dynamics following experimental drought in a humid tropical forest

Treesearch

Tana Wood; W. L. Silver

2012-01-01

[1] Soil moisture is a key driver of biogeochemical processes in terrestrial ecosystems, strongly affecting carbon (C) and nutrient availability as well as trace gas production and consumption in soils. Models predict increasing drought frequency in tropical forest ecosystems, which could feed back on future climate change directly via effects on trace gasdynamics and...

Exploring Learning Performance toward Cognitive Approaches of a Virtual Companion System in LINE App for m-Learning

ERIC Educational Resources Information Center

Hsieh, Sheng-Wen; Wu, Min-Ping

2013-01-01

This paper used a Virtual Companion System (VCS) to examine how specific design variables within virtual learning companion affect the learning process of learners as defined by the cognitive continuum of field-dependent, field-independent and field-mixed learners in LINE app for m-learning. The data were collected from 198 participants in a…

The Relationship among School Safety, School Liking, and Students' Self-Esteem: Based on a Multilevel Mediation Model

ERIC Educational Resources Information Center

Zhang, Xinghui; Xuan, Xin; Chen, Fumei; Zhang, Cai; Luo, Yuhan; Wang, Yun

2016-01-01

Background: Perceptions of school safety have an important effect on students' development. Based on the model of "context-process-outcomes," we examined school safety as a context variable to explore how school safety at the school level affected students' self-esteem. Methods: We used hierarchical linear modeling to examine the link…

Daily Landsat-scale evapotranspiration estimation over a forested landscape in North Carolina, USA, using multi-satellite data fusion

Treesearch

Yun Yang; Martha C. Anderson; Feng Gao; Christopher R. Hain; Kathryn A. Semmens; William P. Kustas; Asko Noormets; Randolph H. Wynne; Valerie A. Thomas; Ge Sun

2017-01-01

As a primary flux in the global water cycle, evapotranspiration (ET) connects hydrologic and biological processes and is directly affected by water and land management, land use change and climate variability. Satellite remote sensing provides an effective means for diagnosing ET patterns over heterogeneous landscapes; however, limitations on the spatial and temporal...

Cognitive levels of performance account for hemispheric lateralisation effects in dyslexic and normally reading children.

PubMed

Heim, Stefan; Grande, Marion; Meffert, Elisabeth; Eickhoff, Simon B; Schreiber, Helen; Kukolja, Juraj; Shah, Nadim Jon; Huber, Walter; Amunts, Katrin

2010-12-01

Recent theories of developmental dyslexia explain reading deficits in terms of deficient phonological awareness, attention, visual and auditory processing, or automaticity. Since dyslexia has a neurobiological basis, the question arises how the reader's proficiency in these cognitive variables affects the brain regions involved in visual word recognition. This question was addressed in two fMRI experiments with 19 normally reading children (Experiment 1) and 19 children with dyslexia (Experiment 2). First, reading-specific brain activation was assessed by contrasting the BOLD signal for reading aloud words vs. overtly naming pictures of real objects. Next, ANCOVAs with brain activation during reading the individuals' scores for all five cognitive variables assessed outside the scanner as covariates were performed. Whereas the normal readers' brain activation during reading showed co-variation effects predominantly in the right hemisphere, the reverse pattern was observed for the dyslexics. In particular, middle frontal gyrus, inferior parietal cortex, and precuneus showed contralateral effects for controls as compared to dyslexics. In line with earlier findings in the literature, these data hint at a global change in hemispheric asymmetry during cognitive processing in dyslexic readers, which, in turn, might affect reading proficiency. Copyright © 2010 Elsevier Inc. All rights reserved.

Hydrological responses to channelization and the formation of valley plugs and shoals

USGS Publications Warehouse

Pierce, Aaron R.; King, Sammy L.

2017-01-01

Rehabilitation of floodplain systems focuses on restoring interactions between the fluvial system and floodplain, however, there is a paucity of information on the effects of valley plugs and shoals on floodplain hydrological processes. We investigated hydrologic regimes in floodplains at three valley plug sites, two shoal sites, and three unchannelized sites. Valley plug sites had altered surface and sub-surface hydrology relative to unchannelized sites, while only sub-surface hydrology was affected at shoal sites. Some of the changes were unexpected, such as reduced flood duration and flood depth in floodplains associated with valley plugs. Our results emphasize the variability associated with hydrologic processes around valley plugs and our rudimentary understanding of the effects associated with these geomorphic features. Water table levels were lower at valley plug sites compared to unchannelized sites, however, valley plug sites had a greater proportion of days when water table inundation was above mean root collar depth than both shoal and unchannelized sites as a result of lower root collar depths and higher deposition rates. This study has provided evidence that valley plugs can affect both surface and sub-surface hydrology in different ways than previously thought and illustrates the variability in hydrological responses to valley plug formation.

Attention, working memory, and grammaticality judgment in typical young adults.

PubMed

Smith, Pamela A

2011-06-01

To examine resource allocation and sentence processing, this study examined the effects of auditory distraction on grammaticality judgment (GJ) of sentences varied by semantics (reversibility) and short-term memory requirements. Experiment 1: Typical young adult females (N = 60) completed a whole-sentence GJ task in distraction (Quiet, Noise, or Talk). Participants judged grammaticality of Passive sentences varied by sentence (length), grammaticality, and reversibility. Reaction time (RT) data were analyzed using a mixed analysis of variance. Experiment 2: A similar group completed a self-paced reading GJ task using the similar materials. Experiment 1: Participants responded faster to Bad and to Nonreversible sentences, and in the Talk distraction. The slowest RTs were noted for Good-Reversible-Padded sentences in the Quiet condition. Experiment 2: Distraction did not differentially affect RTs for sentence components. Verb RTs were slower for Reversible sentences. Results suggest that narrative distraction affected GJ, but by speeding responses, not slowing them. Sentence variables of memory and reversibility slowed RTs, but narrative distraction resulted in faster processing times regardless of individual sentence variables. More explicit, deliberate tasks (self-paced reading) resulted in less effect from distraction. Results are discussed in terms of recent theories about auditory distraction.

Size variability of handwriting in healthy Korean older adults.

PubMed

Yoon, Ji Hye; Kim, Hyanghee; Kim, Jungwan; Park, Eunjeong; Kim, Soo Ryon

2014-04-01

The aim of the present study was to delineate how age-related deterioration affects the handwriting of healthy elderly (HE) subjects. A total of 235 HE (54 males, 181 females) aged 57-91 years participated as subjects in the study. In order to compare the area of handwriting, we divided the participants into two groups: (i) aged 57-74 years; and (ii) aged 75-91 years. The writing stimulus was a four-syllabic word with one-to-one grapheme-to-phoneme correspondence. The size of each syllable in the target word was measured using a software program. Alignment of the word to baseline was assessed using a multiple-choice checklist. As compared with handwriting by the younger group, the older group showed greater variability in the size of the written syllables within the word (P = 0.023). The handwriting was characterized by unequal size among syllables and non-perpendicular alignment, which could be explained by several factors. First, the variability might have resulted from irregular fine movement motor control in older adults. Second, the deterioration of visual feedback and visuomotor integration in normal aging might have affected handwriting performance. In conclusion, variability of handwriting can be sensitive in predicting the aging process. © 2013 Japan Geriatrics Society.

Role of wind forcing and eddy activity in the intraseasonal variability of the barrier layer in the South China Sea

NASA Astrophysics Data System (ADS)

Liang, Zhanlin; Xie, Qiang; Zeng, Lili; Wang, Dongxiao

2018-03-01

In addition to widely discussed seasonal variability, the barrier layer (BL) of the South China Sea (SCS) also exhibits significant intraseasonal variability (ISV) and plays an important role in the upper heat and salt balances. The characteristics and mechanisms of spatiotemporal variations in the BL are investigated using an eddy-resolving ocean model OFES (OGCM For the Earth Simulator) ouput and related atmospheric and oceanic processes. The active intraseasonal BL variability in the SCS occurs mainly during the late summer/autumn and winter and exhibits remarkable differences between these two periods. The BL ISV in late summer/autumn occurs in the southern basin, while in winter, it is limited to the northwestern basin. To further discuss the evolution and driving thermodynamic mechanisms, we quantify the processes that control the variability of intraseasonal BL. Different mechanisms for the intraseasonal BL variability for these two active periods are investigated based on the case study and composite analysis. During late summer/autumn, the active BL in the southern basin is generated by advected and local freshwater, and then decays rapidly with the enhanced wind. In winter, anticyclonic eddy activity is associated with the evolution of the BL by affecting the thermocline and halocline variations, while wind stress and wind stress curl have no obvious influence on BL.

Climate change and water table fluctuation: Implications for raised bog surface variability

NASA Astrophysics Data System (ADS)

Taminskas, Julius; Linkevičienė, Rita; Šimanauskienė, Rasa; Jukna, Laurynas; Kibirkštis, Gintautas; Tamkevičiūtė, Marija

2018-03-01

Cyclic peatland surface variability is influenced by hydrological conditions that highly depend on climate and/or anthropogenic activities. A low water level leads to a decrease of peatland surface and an increase of C emissions into the atmosphere, whereas a high water level leads to an increase of peatland surface and carbon sequestration in peatlands. The main aim of this article is to evaluate the influence of hydrometeorological conditions toward the peatland surface and its feedback toward the water regime. A regional survey of the raised bog water table fluctuation and surface variability was made in one of the largest peatlands in Lithuania. Two appropriate indicators for different peatland surface variability periods (increase and decrease) were detected. The first one is an 200 mm y- 1 average net rainfall over a three-year range. The second one is an average annual water depth of 25-30 cm. The application of these indicators enabled the reconstruction of Čepkeliai peatland surface variability during a 100 year period. Processes of peatland surface variability differ in time and in separate parts of peatland. Therefore, internal subbasins in peatland are formed. Subbasins involve autogenic processes that can later affect their internal hydrology, nutrient status, and vegetation succession. Internal hydrological conditions, surface fluctuation, and vegetation succession in peatland subbasins should be taken into account during evaluation of their state, nature management projects, and other peatland research works.

Determination of the dried product resistance variability and its influence on the product temperature in pharmaceutical freeze-drying.

PubMed

Scutellà, Bernadette; Trelea, Ioan Cristian; Bourlès, Erwan; Fonseca, Fernanda; Passot, Stephanie

2018-07-01

During the primary drying step of the freeze-drying process, mass transfer resistance strongly affects the product temperature, and consequently the final product quality. The main objective of this study was to evaluate the variability of the mass transfer resistance resulting from the dried product layer (R p ) in a manufacturing batch of vials, and its potential effect on the product temperature, from data obtained in a pilot scale freeze-dryer. Sublimation experiments were run at -25 °C and 10 Pa using two different freezing protocols: with spontaneous or controlled ice nucleation. Five repetitions of each condition were performed. Global (pressure rise test) and local (gravimetric) methods were applied as complementary approaches to estimate R p . The global method allowed to assess variability of the evolution of R p with the dried layer thickness between different experiments whereas the local method informed about R p variability at a fixed time within the vial batch. A product temperature variability of approximately ±4.4 °C was defined for a product dried layer thickness of 5 mm. The present approach can be used to estimate the risk of failure of the process due to mass transfer variability when designing freeze-drying cycle. Copyright © 2018 Elsevier B.V. All rights reserved.

Burgers or tofu? Eating between two worlds: risk information seeking and processing during dietary acculturation.

PubMed

Lu, Hang

2015-01-01

This study attempted to examine what factors might motivate Chinese international students, the fastest growing ethnic student group in the United States, to seek and process information about potential health risks from eating American-style food. This goal was accomplished by applying the Risk Information Seeking and Processing (RISP) model to this study. An online 2 (severity: high vs. low) × 2 (coping strategies: present vs. absent) between-subjects experiment was conducted via Qualtrics to evaluate the effects of the manipulated variables on the dependent variables of interest as well as various relationships proposed in the RISP model. A convenience sample of 635 participants was recruited online. Data were analyzed primarily using structural equation modeling (SEM) in AMOS 21.0 with maximum likelihood estimation. The final conceptual model has a good model fit to the data given the sample size. The results showed that although the experimentally manipulated variables failed to cause any significant differences in individuals' perceived severity and self-efficacy, this study largely supported the RISP model's propositions about the sociopsychological factors that explain individual variations in information seeking and processing. More specifically, the findings indicated a prominent role of informational subjective norms and affective responses (both negative and positive emotions) in predicting individuals' information seeking and processing. Future implications and limitations are also discussed.

Influence of long-range atmospheric transport pathways and climate teleconnection patterns on the variability of surface 210Pb and 7Be concentrations in southwestern Europe.

PubMed

Grossi, C; Ballester, J; Serrano, I; Galmarini, S; Camacho, A; Curcoll, R; Morguí, J A; Rodò, X; Duch, M A

2016-12-01

The variability of the atmospheric concentration of the 7 Be and 210 Pb radionuclides is strongly linked to the origin of air masses, the strength of their sources and the processes of wet and dry deposition. It has been shown how these processes and their variability are strongly affected by climate change. Thus, a deeper knowledge of the relationship between the atmospheric radionuclides variability measured close to the ground and these atmospheric processes could help in the analysis of climate scenarios. In the present study, we analyze the atmospheric variability of a 14-year time series of 7 Be and 210 Pb in a Mediterranean coastal city using a synergy of different indicators and tools such as: the local meteorological conditions, global and regional climate indexes and a lagrangian atmospheric transport model. We particularly focus on the relationships between the main pathways of air masses and sun spots occurrence, the variability of the local relative humidity and temperature conditions, and the main modes of regional climate variability, such as the North Atlantic Oscillation (NAO) and the Western Mediterranean Oscillation (WeMO). The variability of the observed atmospheric concentrations of both 7 Be and 210 Pb radionuclides was found to be mainly positively associated to the local climate conditions of temperature and to the pathways of air masses arriving at the station. Measured radionuclide concentrations significantly increase when air masses travel at low tropospheric levels from central Europe and the western part of the Iberian Peninsula, while low concentrations are associated with westerly air masses. We found a significant negative correlation between the WeMO index and the atmospheric variability of both radionuclides and no significant association was observed for the NAO index. Copyright © 2016 Elsevier Ltd. All rights reserved.

Ecological Drivers of Biogeographic Patterns of Soil Archaeal Community

PubMed Central

Zheng, Yuan-Ming; Cao, Peng; Fu, Bojie; Hughes, Jane M.; He, Ji-Zheng

2013-01-01

Knowledge about the biogeography of organisms has long been a focus in ecological research, including the mechanisms that generate and maintain diversity. In this study, we targeted a microbial group relatively underrepresented in the microbial biogeographic literature, the soil Archaea. We surveyed the archaeal abundance and community composition using real-time quantitative PCR and T-RFLP approaches for 105 soil samples from 2 habitat types to identify the archaeal distribution patterns and factors driving these patterns. Results showed that the soil archaeal community was affected by spatial and environmental variables, and 79% and 51% of the community variation was explained in the non-flooded soil (NS) and flooded soil (FS) habitat, respectively, showing its possible biogeographic distribution. The diversity patterns of soil Archaea across the landscape were influenced by a combination of stochastic and deterministic processes. The contribution from neutral processes was higher than that from deterministic processes associated with environmental variables. The variables pH, sample depth and longitude played key roles in determining the archaeal distribution in the NS habitat, while sampling depth, longitude and NH4 +-N were most important in the FS habitat. Overall, there might be similar ecological drivers in the soil archaeal community as in macroorganism communities. PMID:23717418

Long-memory and the sea level-temperature relationship: a fractional cointegration approach.

PubMed

Ventosa-Santaulària, Daniel; Heres, David R; Martínez-Hernández, L Catalina

2014-01-01

Through thermal expansion of oceans and melting of land-based ice, global warming is very likely contributing to the sea level rise observed during the 20th century. The amount by which further increases in global average temperature could affect sea level is only known with large uncertainties due to the limited capacity of physics-based models to predict sea levels from global surface temperatures. Semi-empirical approaches have been implemented to estimate the statistical relationship between these two variables providing an alternative measure on which to base potentially disrupting impacts on coastal communities and ecosystems. However, only a few of these semi-empirical applications had addressed the spurious inference that is likely to be drawn when one nonstationary process is regressed on another. Furthermore, it has been shown that spurious effects are not eliminated by stationary processes when these possess strong long memory. Our results indicate that both global temperature and sea level indeed present the characteristics of long memory processes. Nevertheless, we find that these variables are fractionally cointegrated when sea-ice extent is incorporated as an instrumental variable for temperature which in our estimations has a statistically significant positive impact on global sea level.

Multiscale Model Simulations of Temperature and Relative Humidity for the License Application of the Proposed Yucca Mountain Repository

NASA Astrophysics Data System (ADS)

Buscheck, T.; Glascoe, L.; Sun, Y.; Gansemer, J.; Lee, K.

2003-12-01

For the proposed Yucca Mountain geologic repository for high-level nuclear waste, the planned method of disposal involves the emplacement of cylindrical packages containing the waste inside horizontal tunnels, called emplacement drifts, bored several hundred meters below the ground surface. The emplacement drifts reside in highly fractured, partially saturated volcanic tuff. An important phenomenological consideration for the licensing of the proposed repository at Yucca Mountain is the generation of decay heat by the emplaced waste and the consequences of this decay heat. Changes in temperature will affect the hydrologic and chemical environment at Yucca Mountain. A thermohydrologic-modeling tool is necessary to support the performance assessment of the Engineered Barrier System (EBS) of the proposed repository. This modeling tool must simultaneously account for processes occurring at a scale of a few tens of centimeters around individual waste packages, for processes occurring around the emplacement drifts themselves, and for processes occurring at the multi-kilometer scale of the mountain. Additionally, many other features must be considered including non-isothermal, multiphase-flow in fractured porous rock of variable liquid-phase saturation and thermal radiation and convection in open cavities. The Multiscale Thermohydrologic Model (MSTHM) calculates the following thermohydrologic (TH) variables: temperature, relative humidity, liquid-phase saturation, evaporation rate, air-mass fraction, gas-phase pressure, capillary pressure, and liquid- and gas-phase fluxes. The TH variables are determined as a function of position along each of the emplacement drifts in the repository and as a function of waste-package (WP) type. These variables are determined at various generic locations within the emplacement drifts, including the waste package and drip-shield surfaces and in the invert; they are also determined at various generic locations in the adjoining host rock; these variables are determined every 20 m for each emplacement drift in the repository. The MSTHM accounts for 3-D drift-scale and mountain-scale heat flow and captures the influence of the key engineering-design variables and natural-system factors affecting TH conditions in the emplacement drifts and adjoining host rock. Presented is a synopsis of recent MSTHM calculations conducted to support the Total System Performance Assessment for the License Application (TSPA-LA). This work was performed under the auspices of the U.S. Department of Energy by University of California Lawrence Livermore National Laboratory under contract No. W-7405-Eng-48.

Systematic review of the neural basis of social cognition in patients with mood disorders

PubMed Central

Cusi, Andrée M.; Nazarov, Anthony; Holshausen, Katherine; MacQueen, Glenda M.; McKinnon, Margaret C.

2012-01-01

Background This review integrates neuroimaging studies of 2 domains of social cognition — emotion comprehension and theory of mind (ToM) — in patients with major depressive disorder and bipolar disorder. The influence of key clinical and method variables on patterns of neural activation during social cognitive processing is also examined. Methods Studies were identified using PsycINFO and PubMed (January 1967 to May 2011). The search terms were “fMRI,” “emotion comprehension,” “emotion perception,” “affect comprehension,” “affect perception,” “facial expression,” “prosody,” “theory of mind,” “mentalizing” and “empathy” in combination with “major depressive disorder,” “bipolar disorder,” “major depression,” “unipolar depression,” “clinical depression” and “mania.” Results Taken together, neuroimaging studies of social cognition in patients with mood disorders reveal enhanced activation in limbic and emotion-related structures and attenuated activity within frontal regions associated with emotion regulation and higher cognitive functions. These results reveal an overall lack of inhibition by higher-order cognitive structures on limbic and emotion-related structures during social cognitive processing in patients with mood disorders. Critically, key variables, including illness burden, symptom severity, comorbidity, medication status and cognitive load may moderate this pattern of neural activation. Limitations Studies that did not include control tasks or a comparator group were included in this review. Conclusion Further work is needed to examine the contribution of key moderator variables and to further elucidate the neural networks underlying altered social cognition in patients with mood disorders. The neural networks underlying higher-order social cognitive processes, including empathy, remain unexplored in patients with mood disorders. PMID:22297065

How does alcohol advertising influence underage drinking? The role of desirability, identification and skepticism.

PubMed

Austin, Erica Weintraub; Chen, Meng-Jinn; Grube, Joel W

2006-04-01

To investigate, using an information processing model, how persuasive media messages for alcohol use lead to concurring beliefs and behaviors among youths. Data were collected in 2000-2001 using computer-assisted, self-administered interviews with youths aged 9-17 years (n = 652). Latent variable structural equations models showed that skepticism was negatively associated with positive affect toward alcohol portrayals and positively with the desire to emulate characters portrayed in alcohol advertisements. These, in turn, predicted expectancies and liking of/desire for beer toys and brands, which predicted alcohol use. Parental guidance decreased alcohol use directly and indirectly by lessening influences of positive affect toward advertising. Media alcohol portrayals influence children's drinking through a progressive decision-making process, with its influence underestimated by typical exposure-and-effects analyses.

Seychelles Dome variability in a high resolution ocean model

NASA Astrophysics Data System (ADS)

Nyadjro, E. S.; Jensen, T.; Richman, J. G.; Shriver, J. F.

2016-02-01

The Seychelles-Chagos Thermocline Ridge (SCTR; 5ºS-10ºS, 50ºE-80ºE) in the tropical Southwest Indian Ocean (SWIO) has been recognized as a region of prominence with regards to climate variability in the Indian Ocean. Convective activities in this region have regional consequences as it affect socio-economic livelihood of the people especially in the countries along the Indian Ocean rim. The SCTR is characterized by a quasi-permanent upwelling that is often associated with thermocline shoaling. This upwelling affects sea surface temperature (SST) variability. We present results on the variability and dynamics of the SCTR as simulated by the 1/12º high resolution HYbrid Coordinate Ocean Model (HYCOM). It is observed that locally, wind stress affects SST via Ekman pumping of cooler subsurface waters, mixing and anomalous zonal advection. Remotely, wind stress curl in the eastern equatorial Indian Ocean generates westward-propagating Rossby waves that impacts the depth of the thermocline which in turn impacts SST variability in the SCTR region. The variability of the contributions of these processes, especially with regard to the Indian Ocean Dipole (IOD) are further examined. In a typical positive IOD (PIOD) year, the net vertical velocity in the SCTR is negative year-round as easterlies along the region are intensified leading to a strong positive curl. This vertical velocity is caused mainly by anomalous local Ekman downwelling (with peak during September-November), a direct opposite to the climatology scenario when local Ekman pumping is positive (upwelling favorable) year-round. The anomalous remote contribution to the vertical velocity changes is minimal especially during the developing and peak stages of PIOD events. In a typical negative IOD (NIOD) year, anomalous vertical velocity is positive almost year-round with peaks in May and October. The remote contribution is positive, in contrast to the climatology and most of the PIOD years.

Operator agency in process intervention: tampering versus application of tacit knowledge

NASA Astrophysics Data System (ADS)

Van Gestel, P.; Pons, D. J.; Pulakanam, V.

2015-09-01

Statistical process control (SPC) theory takes a negative view of adjustment of process settings, which is termed tampering. In contrast, quality and lean programmes actively encourage operators to acts of intervention and personal agency in the improvement of production outcomes. This creates a conflict that requires operator judgement: How does one differentiate between unnecessary tampering and needful intervention? Also, difficult is that operators apply tacit knowledge to such judgements. There is a need to determine where in a given production process the operators are applying tacit knowledge, and whether this is hindering or aiding quality outcomes. The work involved the conjoint application of systems engineering, statistics, and knowledge management principles, in the context of a case study. Systems engineering was used to create a functional model of a real plant. Actual plant data were analysed with the statistical methods of ANOVA, feature selection, and link analysis. This identified the variables to which the output quality was most sensitive. These key variables were mapped back to the functional model. Fieldwork was then directed to those areas to prospect for operator judgement activities. A natural conversational approach was used to determine where and how operators were applying judgement. This contrasts to the interrogative approach of conventional knowledge management. Data are presented for a case study of a meat rendering plant. The results identify specific areas where operators' tacit knowledge and mental model contribute to quality outcomes and untangles the motivations behind their agency. Also evident is how novice and expert operators apply their knowledge differently. Novices were focussed on meeting throughput objectives, and their incomplete understanding of the plant characteristics led them to inadvertently sacrifice quality in the pursuit of productivity in certain situations. Operators' responses to the plant are affected by their individual mental models of the plant, which differ between operators and have variable validity. Their behaviour is also affected by differing interpretations of how their personal agency should be applied to the achievement of production objectives. The methodology developed here is an integration of systems engineering, statistical analysis, and knowledge management. It shows how to determine where in a given production process the operator intervention is occurring, how it affects quality outcomes, and what tacit knowledge operators are using. It thereby assists the continuous quality improvement processes in a different way to SPC. A second contribution is the provision of a novel methodology for knowledge management, one that circumvents the usual codification barriers to knowledge management.

A probabilistic approach to quantifying spatial patterns of flow regimes and network-scale connectivity

NASA Astrophysics Data System (ADS)

Garbin, Silvia; Alessi Celegon, Elisa; Fanton, Pietro; Botter, Gianluca

2017-04-01

The temporal variability of river flow regime is a key feature structuring and controlling fluvial ecological communities and ecosystem processes. In particular, streamflow variability induced by climate/landscape heterogeneities or other anthropogenic factors significantly affects the connectivity between streams with notable implication for river fragmentation. Hydrologic connectivity is a fundamental property that guarantees species persistence and ecosystem integrity in riverine systems. In riverine landscapes, most ecological transitions are flow-dependent and the structure of flow regimes may affect ecological functions of endemic biota (i.e., fish spawning or grazing of invertebrate species). Therefore, minimum flow thresholds must be guaranteed to support specific ecosystem services, like fish migration, aquatic biodiversity and habitat suitability. In this contribution, we present a probabilistic approach aiming at a spatially-explicit, quantitative assessment of hydrologic connectivity at the network-scale as derived from river flow variability. Dynamics of daily streamflows are estimated based on catchment-scale climatic and morphological features, integrating a stochastic, physically based approach that accounts for the stochasticity of rainfall with a water balance model and a geomorphic recession flow model. The non-exceedance probability of ecologically meaningful flow thresholds is used to evaluate the fragmentation of individual stream reaches, and the ensuing network-scale connectivity metrics. A multi-dimensional Poisson Process for the stochastic generation of rainfall is used to evaluate the impact of climate signature on reach-scale and catchment-scale connectivity. The analysis shows that streamflow patterns and network-scale connectivity are influenced by the topology of the river network and the spatial variability of climatic properties (rainfall, evapotranspiration). The framework offers a robust basis for the prediction of the impact of land-use/land-cover changes and river regulation on network-scale connectivity.

Factors affecting exits from homelessness among persons with serious mental illness and substance use disorders

PubMed Central

Gabrielian, Sonya; Bromley, Elizabeth; Hellemann, Gerhard S.; Kern, Robert S.; Goldenson, Nicholas I.; Danley, Megan E.; Young, Alexander S.

2015-01-01

Objective We sought to understand the housing trajectories of homeless consumers with serious mental illness (SMI) and co-occurring substance use disorders (SUD) and to identify factors that best-predicted achievement of independent housing. Methods Using administrative data, we identified homeless persons with SMI and SUD admitted to a residential rehabilitation program from 12/2008-11/2011. On a random sample (n=36), we assessed a range of potential predictors of housing outcomes, including symptoms, cognition, and social/community supports. We used the Residential Time-Line Follow-Back (TLFB) Inventory to gather housing histories since exiting rehabilitation and identify housing outcomes. We used recursive partitioning to identify variables that best-differentiated participants by these outcomes. Results We identified three housing trajectories: stable housing (n=14); unstable housing (n=15); and continuously engaged in housing services (n=7). Using recursive partitioning, two variables (symbol digit modalities test (SDMT), a neurocognitive speed of processing measure and Behavior and Symptom Identification Scale (BASIS)-relationships subscale, which quantifies symptoms affecting relationships) were sufficient to capture information provided by 26 predictors to classify participants by housing outcome. Participants predicted to continuously engage in services had impaired processing speeds (SDMT score<32.5). Among consumers with SDMT score≥32.5, those predicted to achieve stable housing had fewer interpersonal symptoms (BASIS-relationships score<0.81) than those predicted to have unstable housing. This model explains 57% of this sample's variability and 14% of this population's variability in housing outcomes. Conclusion As cognition and symptoms influencing relationships predicted housing outcomes for homeless adults with SMI and SUD, cognitive and social skills trainings may be useful for this population. PMID:25919839

Factors affecting exits from homelessness among persons with serious mental illness and substance use disorders.

PubMed

Gabrielian, Sonya; Bromley, Elizabeth; Hellemann, Gerhard S; Kern, Robert S; Goldenson, Nicholas I; Danley, Megan E; Young, Alexander S

2015-04-01

We sought to understand the housing trajectories of homeless consumers with serious mental illness (SMI) and co-occurring substance use disorders (SUD) and to identify factors that best predicted achievement of independent housing. Using administrative data, we identified homeless persons with SMI and SUD admitted to a residential rehabilitation program from December 2008 to November 2011. Our primary outcome measure was independent housing status. On a random sample (N = 36), we assessed a range of potential predictors of housing outcomes, including symptoms, cognition, and social/community supports. We used the Residential Time-Line Follow-Back (TLFB) Inventory to gather housing histories since exiting rehabilitation and to identify housing outcomes. We used Recursive Partitioning (RP) to identify variables that best differentiated participants by these outcomes. We identified 3 housing trajectories: stable housing (n = 14), unstable housing (n = 15), and continuously engaged in housing services (n = 7). In RP analysis, 2 variables (Symbol Digit Modalities Test [SDMT], a neurocognitive speed of processing measure, and Behavior and Symptom Identification Scale [BASIS-24] Relationships subscale, which quantifies symptoms affecting relationships) were sufficient to capture information provided by 26 predictors to classify participants by housing outcome. Participants predicted to continuously engage in services had impaired processing speeds (SDMT score < 32.5). Among consumers with SDMT score ≥ 32.5, those predicted to achieve stable housing had fewer interpersonal symptoms (BASIS-24 Relationships subscale score < 0.81) than those predicted to have unstable housing. This model explains 57% of this sample's variability and 14% of this population's variability in housing outcomes. Because cognition and symptoms influencing relationships predicted housing outcomes for homeless adults with SMI and SUD, cognitive and social skills training may be useful for this population. © Copyright 2015 Physicians Postgraduate Press, Inc.

The spanning set indicates that variability during the stance period of running is affected by footwear.

PubMed

Kurz, Max J; Stergiou, Nicholas

2003-04-01

Sensory information the foot receives appears to be related to kinematic variability. Since footwear material densities affect sensory information, footwear may be an important factor that dictates variability. This study hypothesized that modifications in footwear would result in changes in kinematic variability during the running stance period. Subjects ran on a treadmill for three conditions: hard shoe, soft shoe and barefoot. The spanning sets of the mean ensemble curves of the knee and ankle changes for each condition were used to define variability. Variability was significantly larger in the barefoot condition in comparison with the two footwear conditions for both joints. These results suggest that variability can be affected by peripheral sensory information. The spanning set methodology can be utilized to examine changes in variability.

GWM-a ground-water management process for the U.S. Geological Survey modular ground-water model (MODFLOW-2000)

USGS Publications Warehouse

Ahlfeld, David P.; Barlow, Paul M.; Mulligan, Anne E.

2005-01-01

GWM is a Ground?Water Management Process for the U.S. Geological Survey modular three?dimensional ground?water model, MODFLOW?2000. GWM uses a response?matrix approach to solve several types of linear, nonlinear, and mixed?binary linear ground?water management formulations. Each management formulation consists of a set of decision variables, an objective function, and a set of constraints. Three types of decision variables are supported by GWM: flow?rate decision variables, which are withdrawal or injection rates at well sites; external decision variables, which are sources or sinks of water that are external to the flow model and do not directly affect the state variables of the simulated ground?water system (heads, streamflows, and so forth); and binary variables, which have values of 0 or 1 and are used to define the status of flow?rate or external decision variables. Flow?rate decision variables can represent wells that extend over one or more model cells and be active during one or more model stress periods; external variables also can be active during one or more stress periods. A single objective function is supported by GWM, which can be specified to either minimize or maximize the weighted sum of the three types of decision variables. Four types of constraints can be specified in a GWM formulation: upper and lower bounds on the flow?rate and external decision variables; linear summations of the three types of decision variables; hydraulic?head based constraints, including drawdowns, head differences, and head gradients; and streamflow and streamflow?depletion constraints. The Response Matrix Solution (RMS) Package of GWM uses the Ground?Water Flow Process of MODFLOW to calculate the change in head at each constraint location that results from a perturbation of a flow?rate variable; these changes are used to calculate the response coefficients. For linear management formulations, the resulting matrix of response coefficients is then combined with other components of the linear management formulation to form a complete linear formulation; the formulation is then solved by use of the simplex algorithm, which is incorporated into the RMS Package. Nonlinear formulations arise for simulated conditions that include water?table (unconfined) aquifers or head?dependent boundary conditions (such as streams, drains, or evapotranspiration from the water table). Nonlinear formulations are solved by sequential linear programming; that is, repeated linearization of the nonlinear features of the management problem. In this approach, response coefficients are recalculated for each iteration of the solution process. Mixed?binary linear (or mildly nonlinear) formulations are solved by use of the branch and bound algorithm, which is also incorporated into the RMS Package. Three sample problems are provided to demonstrate the use of GWM for typical ground?water flow management problems. These sample problems provide examples of how GWM input files are constructed to specify the decision variables, objective function, constraints, and solution process for a GWM run. The GWM Process runs with the MODFLOW?2000 Global and Ground?Water Flow Processes, but in its current form GWM cannot be used with the Observation, Sensitivity, Parameter?Estimation, or Ground?Water Transport Processes. The GWM Process is written with a modular structure so that new objective functions, constraint types, and solution algorithms can be added.

The Effects Of Urban Landscape Patterns On Rainfall-Runoff Processes At Small Scale

NASA Astrophysics Data System (ADS)

Chen, L.

2016-12-01

Many studies have indicated that urban landscape change may alter rainfall-runoff processes. However, how urban landscape pattern affect this process is little addressed. In this study, the hydrological effects of landscape pattern on rainfall-runoff processes at small-scale was explored. Twelve residential blocks with independent drainage systems in Beijing were selected as case study areas. Impervious metrics of these blocks, i.e., total impervious area (TIA) and directly connected impervious area (DCIA), were identified. A drainage index describing catchment general drainage load and the overland flow distance, Ad, was estimated and used as one of the landscape spatial metrics. Three scenarios were designed to test the potential influence of impervious surface pattern on runoff processes. Runoff variables including total and peak runoff depth (Qt and Qp) were simulated under different rainfall conditions by Storm Water Management Model (SWMM). The relationship between landscape patterns and runoff variables were analyzed, and further among the three scenarios. The results demonstrated that, in small urban blocks, spatial patterns have inherent influences on rainfall-runoff processes. Specifically, (1) Imperviousness acts as effective indicators in predicting both Qt and Qp. As rainfall intensity increases, the major affecting factor changes from DCIA to TIA for both Qt and Qp; (2) Increasing the size of drainage area dominated by each drainage inlet will benefit the block peak flow mitigation; (3) Different spatial concentrations of impervious surfaces have inherent influences on Qp, when impervious surfaces located away from the outlet can reduce the peak flow discharge. These findings may provide insights into the role of urban landscape patterns in driving rainfall-runoff responses in urbanization, which is essential for urban planning and stormwater management.

Skeletal muscle repair in a mouse model of nemaline myopathy

PubMed Central

Sanoudou, Despina; Corbett, Mark A.; Han, Mei; Ghoddusi, Majid; Nguyen, Mai-Anh T.; Vlahovich, Nicole; Hardeman, Edna C.; Beggs, Alan H.

2012-01-01

Nemaline myopathy (NM), the most common non-dystrophic congenital myopathy, is a variably severe neuromuscular disorder for which no effective treatment is available. Although a number of genes have been identified in which mutations can cause NM, the pathogenetic mechanisms leading to the phenotypes are poorly understood. To address this question, we examined gene expression patterns in an NM mouse model carrying the human Met9Arg mutation of alpha-tropomyosin slow (Tpm3). We assessed five different skeletal muscles from affected mice, which are representative of muscles with differing fiber-type compositions, different physiological specializations and variable degrees of pathology. Although these same muscles in non-affected mice showed marked variation in patterns of gene expression, with diaphragm being the most dissimilar, the presence of the mutant protein in nemaline muscles resulted in a more similar pattern of gene expression among the muscles. This result suggests a common process or mechanism operating in nemaline muscles independent of the variable degrees of pathology. Transcriptional and protein expression data indicate the presence of a repair process and possibly delayed maturation in nemaline muscles. Markers indicative of satellite cell number, activated satellite cells and immature fibers including M-Cadherin, MyoD, desmin, Pax7 and Myf6 were elevated by western-blot analysis or immunohistochemistry. Evidence suggesting elevated focal repair was observed in nemaline muscle in electron micrographs. This analysis reveals that NM is characterized by a novel repair feature operating in multiple different muscles. PMID:16877500

Skeletal muscle repair in a mouse model of nemaline myopathy.

PubMed

Sanoudou, Despina; Corbett, Mark A; Han, Mei; Ghoddusi, Majid; Nguyen, Mai-Anh T; Vlahovich, Nicole; Hardeman, Edna C; Beggs, Alan H

2006-09-01

Nemaline myopathy (NM), the most common non-dystrophic congenital myopathy, is a variably severe neuromuscular disorder for which no effective treatment is available. Although a number of genes have been identified in which mutations can cause NM, the pathogenetic mechanisms leading to the phenotypes are poorly understood. To address this question, we examined gene expression patterns in an NM mouse model carrying the human Met9Arg mutation of alpha-tropomyosin slow (Tpm3). We assessed five different skeletal muscles from affected mice, which are representative of muscles with differing fiber-type compositions, different physiological specializations and variable degrees of pathology. Although these same muscles in non-affected mice showed marked variation in patterns of gene expression, with diaphragm being the most dissimilar, the presence of the mutant protein in nemaline muscles resulted in a more similar pattern of gene expression among the muscles. This result suggests a common process or mechanism operating in nemaline muscles independent of the variable degrees of pathology. Transcriptional and protein expression data indicate the presence of a repair process and possibly delayed maturation in nemaline muscles. Markers indicative of satellite cell number, activated satellite cells and immature fibers including M-Cadherin, MyoD, desmin, Pax7 and Myf6 were elevated by western-blot analysis or immunohistochemistry. Evidence suggesting elevated focal repair was observed in nemaline muscle in electron micrographs. This analysis reveals that NM is characterized by a novel repair feature operating in multiple different muscles.

Whole blood flow cytometry measurements of in vivo platelet activation in critically-Ill patients are influenced by variability in blood sampling techniques.

PubMed

Rondina, Matthew T; Grissom, Colin K; Men, Shaohua; Harris, Estelle S; Schwertz, Hansjorg; Zimmerman, Guy A; Weyrich, Andrew S

2012-06-01

Flow cytometry is often used to measure in vivo platelet activation in critically-ill patients. Variability in blood sampling techniques, which may confound these measurements, remains poorly characterized. Platelet activation was measured by flow cytometry performed on arterial and venous blood from 116 critically-ill patients. We determined how variability in vascular sampling site, processing times, and platelet counts influenced levels of platelet-monocyte aggregates (PMA), PAC-1 binding (for glycoprotein (GP) IIbIIIa), and P-selectin (P-SEL) expression. Levels of PMA, but not PAC-1 binding or P-SEL expression, were significantly affected by variability in vascular sampling site. Average PMA levels were approximately 60% higher in whole blood drawn from an arterial vessel compared to venous blood (16.2±1.8% vs. 10.7±1.2%, p<0.05). Levels of PMA in both arterial and venous blood increased significantly during ex vivo processing delays (1.7% increase for every 10 minute delay, p<0.05). In contrast, PAC-1 binding and P-SEL expression were unaffected by processing delays. Levels of PMA, but not PAC-1 binding or P-SEL expression, were correlated with platelet count quartiles (9.4±1.6% for the lowest quartile versus 15.4±1.6% for the highest quartile, p<0.05). In critically-ill patients, variability in vascular sampling site, processing times, and platelet counts influence levels of PMA, but not PAC-1 binding or P-SEL expression. These data demonstrate the need for rigorous adherence to blood sampling protocols, particularly when levels of PMA, which are most sensitive to variations in blood collection, are measured for detection of in vivo platelet activation. Copyright © 2011 Elsevier Ltd. All rights reserved.

Variable compensation in Primary Healthcare: a report on the experience in Curitiba, Rio de Janeiro, Brazil, and Lisbon, Portugal.

PubMed

Poli Neto, Paulo; Faoro, Nilza Teresinha; Prado Júnior, José Carlos do; Pisco, Luís Augusto Coelho

2016-05-01

How professionals are compensated may affect how they perform their tasks. Fixed compensation may take the form of wages, payment for productivity or capitation. In addition to fixed compensation, there are numerous mechanisms for variable compensation. This article describes the experience of Curitiba and Rio de Janeiro in Brazil, and Lisbon in Portugal, using different models of performance-based compensation. In all three of these examples, management felt the need to offer monetary reward to achieve certain goals. The indicators analyzed the structure, processes and outcomes, and assessed professionals individual and as part of healthcare teams. In Lisbon, variable compensation can be as high as 40% of the base wage, while in Curitiba and Rio de Janeiro it is limited to 10%. Despite the growing use of this management tool in Brazil and the world, further studies are required to analyze the effectiveness of variable compensation.

Modelling Escherichia coli concentrations in the tidal Scheldt river and estuary.

PubMed

de Brauwere, Anouk; de Brye, Benjamin; Servais, Pierre; Passerat, Julien; Deleersnijder, Eric

2011-04-01

Recent observations in the tidal Scheldt River and Estuary revealed a poor microbiological water quality and substantial variability of this quality which can hardly be assigned to a single factor. To assess the importance of tides, river discharge, point sources, upstream concentrations, mortality and settling a new model (SLIM-EC) was built. This model was first validated by comparison with the available field measurements of Escherichia coli (E. coli, a common fecal bacterial indicator) concentrations. The model simulations agreed well with the observations, and in particular were able to reproduce the observed long-term median concentrations and variability. Next, the model was used to perform sensitivity runs in which one process/forcing was removed at a time. These simulations revealed that the tide, upstream concentrations and the mortality process are the primary factors controlling the long-term median E. coli concentrations and the observed variability. The tide is crucial to explain the increased concentrations upstream of important inputs, as well as a generally increased variability. Remarkably, the wastewater treatment plants discharging in the study domain do not seem to have a significant impact. This is due to a dilution effect, and to the fact that the concentrations coming from upstream (where large cities are located) are high. Overall, the settling process as it is presently described in the model does not significantly affect the simulated E. coli concentrations. Copyright © 2011 Elsevier Ltd. All rights reserved.

Multivariate analysis of sludge disintegration by microwave-hydrogen peroxide pretreatment process.

PubMed

Ya-Wei, Wang; Cheng-Min, Gui; Xiao-Tang, Ni; Mei-Xue, Chen; Yuan-Song, Wei

2015-01-01

Microwave irradiation (with H2O2) has been shown to offer considerable advantages owing to its flexible control, low overall cost, and resulting higher soluble chemical oxygen demand (SCOD); accordingly, the method has been proposed recently as a means of improving sludge disintegration. However, the key factor controlling this sludge pretreatment process, pH, has received insufficient attention to date. To address this, the response surface approach (central composite design) was applied to evaluate the effects of total suspended solids (TSS, 2-20 g/L), pH (4-10), and H2O2 dosage (0-2 w/w) and their interactions on 16 response variables (e.g., SCODreleased, pH, H2O2remaining). The results demonstrated that all three factors affect sludge disintegration significantly, and no pronounced interactions between response variables were observed during disintegration, except for three variables (TCOD, TSSremaining, and H2O2 remaining). Quadratic predictive models were constructed for all 16 response variables (R(2): 0.871-0.991). Taking soluble chemical oxygen demand (SCOD) as an example, the model and coefficients derived above were able to predict the performance of microwave pretreatment (enhanced by H2O2 and pH adjustment) from previously published studies. The predictive models developed were able to optimize the treatment process for multiple disintegration objectives. Copyright © 2014 Elsevier B.V. All rights reserved.

Spatio-Temporal Process Variability in Watershed Scale Wetland Restoration Planning

NASA Astrophysics Data System (ADS)

Evenson, G. R.

2012-12-01

Watershed scale restoration decision making processes are increasingly informed by quantitative methodologies providing site-specific restoration recommendations - sometimes referred to as "systematic planning." The more advanced of these methodologies are characterized by a coupling of search algorithms and ecological models to discover restoration plans that optimize environmental outcomes. Yet while these methods have exhibited clear utility as decision support toolsets, they may be critiqued for flawed evaluations of spatio-temporally variable processes fundamental to watershed scale restoration. Hydrologic and non-hydrologic mediated process connectivity along with post-restoration habitat dynamics, for example, are commonly ignored yet known to appreciably affect restoration outcomes. This talk will present a methodology to evaluate such spatio-temporally complex processes in the production of watershed scale wetland restoration plans. Using the Tuscarawas Watershed in Eastern Ohio as a case study, a genetic algorithm will be coupled with the Soil and Water Assessment Tool (SWAT) to reveal optimal wetland restoration plans as measured by their capacity to maximize nutrient reductions. Then, a so-called "graphical" representation of the optimization problem will be implemented in-parallel to promote hydrologic and non-hydrologic mediated connectivity amongst existing wetlands and sites selected for restoration. Further, various search algorithm mechanisms will be discussed as a means of accounting for temporal complexities such as post-restoration habitat dynamics. Finally, generalized patterns of restoration plan optimality will be discussed as an alternative and possibly superior decision support toolset given the complexity and stochastic nature of spatio-temporal process variability.

Process Evaluation of AISI 4340 Steel Manufactured by Laser Powder Bed Fusion

NASA Astrophysics Data System (ADS)

Jelis, Elias; Hespos, Michael R.; Ravindra, Nuggehalli M.

2018-01-01

Laser powder bed fusion (L-PBF) involves the consolidation of metal powder, layer by layer, through laser melting and solidification. In this study, process parameters are optimized for AISI 4340 steel to produce dense and homogeneous structures. The optimized process parameters produce mechanical properties at the center of the build plate that are comparable to wrought in the vertical and horizontal orientations after heat treatment and machining. Four subsequent builds are filled with specimens to evaluate the mechanical behavior as a function of location and orientation. Variations in the mechanical properties are likely due to recoater blade interactions with the powder and uneven gas flow. The results obtained in this study are analyzed to assess the reliability and reproducibility of the process. A different build evaluates the performance of near-net-shaped tensile specimens angled 35°-90° from the build plate surface (horizontal). Ductility measurements and surface roughness vary significantly as a function of the build angle. In the stress-relieved and as-built conditions, the mechanical behavior of vertically oriented specimens exhibits somewhat lower and more variable ductility than horizontally oriented specimens. Therefore, several process variables affect the mechanical properties of parts produced by the L-PBF process.

Humor drawings evoked temporal and spectral EEG processes

PubMed Central

Kuo, Hsien-Chu; Chuang, Shang-Wen

2017-01-01

Abstract The study aimed to explore the humor processing elicited through the manipulation of artistic drawings. Using the Comprehension–Elaboration Theory of humor as the main research background, the experiment manipulated the head portraits of celebrities based on the independent variables of facial deformation (large/small) and addition of affective features (positive/negative). A 64-channel electroencephalography was recorded in 30 participants while viewing the incongruous drawings of celebrities. The electroencephalography temporal and spectral responses were measured during the three stages of humor which included incongruity detection, incongruity comprehension and elaboration of humor. Analysis of event-related potentials indicated that for humorous vs non-humorous drawings, facial deformation and the addition of affective features significantly affected the degree of humor elicited, specifically: large > small deformation; negative > positive affective features. The N170, N270, N400, N600-800 and N900-1200 components showed significant differences, particularly in the right prefrontal and frontal regions. Analysis of event-related spectral perturbation showed significant differences in the theta band evoked in the anterior cingulate cortex, parietal region and posterior cingulate cortex; and in the alpha and beta bands in the motor areas. These regions are involved in emotional processing, memory retrieval, and laughter and feelings of amusement induced by elaboration of the situation. PMID:28402573

The Socio-Moral Image Database (SMID): A novel stimulus set for the study of social, moral and affective processes

PubMed Central

Bode, Stefan; Murawski, Carsten; Laham, Simon M.

2018-01-01

A major obstacle for the design of rigorous, reproducible studies in moral psychology is the lack of suitable stimulus sets. Here, we present the Socio-Moral Image Database (SMID), the largest standardized moral stimulus set assembled to date, containing 2,941 freely available photographic images, representing a wide range of morally (and affectively) positive, negative and neutral content. The SMID was validated with over 820,525 individual judgments from 2,716 participants, with normative ratings currently available for all images on affective valence and arousal, moral wrongness, and relevance to each of the five moral values posited by Moral Foundations Theory. We present a thorough analysis of the SMID regarding (1) inter-rater consensus, (2) rating precision, and (3) breadth and variability of moral content. Additionally, we provide recommendations for use aimed at efficient study design and reproducibility, and outline planned extensions to the database. We anticipate that the SMID will serve as a useful resource for psychological, neuroscientific and computational (e.g., natural language processing or computer vision) investigations of social, moral and affective processes. The SMID images, along with associated normative data and additional resources are available at https://osf.io/2rqad/. PMID:29364985

Visual Complexity and Affect: Ratings Reflect More Than Meets the Eye.

PubMed

Madan, Christopher R; Bayer, Janine; Gamer, Matthias; Lonsdorf, Tina B; Sommer, Tobias

2017-01-01

Pictorial stimuli can vary on many dimensions, several aspects of which are captured by the term 'visual complexity.' Visual complexity can be described as, "a picture of a few objects, colors, or structures would be less complex than a very colorful picture of many objects that is composed of several components." Prior studies have reported a relationship between affect and visual complexity, where complex pictures are rated as more pleasant and arousing. However, a relationship in the opposite direction, an effect of affect on visual complexity, is also possible; emotional arousal and valence are known to influence selective attention and visual processing. In a series of experiments, we found that ratings of visual complexity correlated with affective ratings, and independently also with computational measures of visual complexity. These computational measures did not correlate with affect, suggesting that complexity ratings are separately related to distinct factors. We investigated the relationship between affect and ratings of visual complexity, finding an 'arousal-complexity bias' to be a robust phenomenon. Moreover, we found this bias could be attenuated when explicitly indicated but did not correlate with inter-individual difference measures of affective processing, and was largely unrelated to cognitive and eyetracking measures. Taken together, the arousal-complexity bias seems to be caused by a relationship between arousal and visual processing as it has been described for the greater vividness of arousing pictures. The described arousal-complexity bias is also of relevance from an experimental perspective because visual complexity is often considered a variable to control for when using pictorial stimuli.

Visual Complexity and Affect: Ratings Reflect More Than Meets the Eye

PubMed Central

Madan, Christopher R.; Bayer, Janine; Gamer, Matthias; Lonsdorf, Tina B.; Sommer, Tobias

2018-01-01

Pictorial stimuli can vary on many dimensions, several aspects of which are captured by the term ‘visual complexity.’ Visual complexity can be described as, “a picture of a few objects, colors, or structures would be less complex than a very colorful picture of many objects that is composed of several components.” Prior studies have reported a relationship between affect and visual complexity, where complex pictures are rated as more pleasant and arousing. However, a relationship in the opposite direction, an effect of affect on visual complexity, is also possible; emotional arousal and valence are known to influence selective attention and visual processing. In a series of experiments, we found that ratings of visual complexity correlated with affective ratings, and independently also with computational measures of visual complexity. These computational measures did not correlate with affect, suggesting that complexity ratings are separately related to distinct factors. We investigated the relationship between affect and ratings of visual complexity, finding an ‘arousal-complexity bias’ to be a robust phenomenon. Moreover, we found this bias could be attenuated when explicitly indicated but did not correlate with inter-individual difference measures of affective processing, and was largely unrelated to cognitive and eyetracking measures. Taken together, the arousal-complexity bias seems to be caused by a relationship between arousal and visual processing as it has been described for the greater vividness of arousing pictures. The described arousal-complexity bias is also of relevance from an experimental perspective because visual complexity is often considered a variable to control for when using pictorial stimuli. PMID:29403412

Heritability of Intraindividual Mean and Variability of Positive and Negative Affect.

PubMed

Zheng, Yao; Plomin, Robert; von Stumm, Sophie

2016-12-01

Positive affect (e.g., attentiveness) and negative affect (e.g., upset) fluctuate over time. We examined genetic influences on interindividual differences in the day-to-day variability of affect (i.e., ups and downs) and in average affect over the duration of a month. Once a day, 17-year-old twins in the United Kingdom ( N = 447) rated their positive and negative affect online. The mean and standard deviation of each individual's daily ratings across the month were used as the measures of that individual's average affect and variability of affect. Analyses revealed that the average of negative affect was significantly heritable (.53), but the average of positive affect was not; instead, the latter showed significant shared environmental influences (.42). Fluctuations across the month were significantly heritable for both negative affect (.54) and positive affect (.34). The findings support the two-factor theory of affect, which posits that positive affect is more situational and negative affect is more dispositional.

Heritability of Intraindividual Mean and Variability of Positive and Negative Affect

PubMed Central

Zheng, Yao; Plomin, Robert; von Stumm, Sophie

2016-01-01

Positive affect (e.g., attentiveness) and negative affect (e.g., upset) fluctuate over time. We examined genetic influences on interindividual differences in the day-to-day variability of affect (i.e., ups and downs) and in average affect over the duration of a month. Once a day, 17-year-old twins in the United Kingdom (N = 447) rated their positive and negative affect online. The mean and standard deviation of each individual’s daily ratings across the month were used as the measures of that individual’s average affect and variability of affect. Analyses revealed that the average of negative affect was significantly heritable (.53), but the average of positive affect was not; instead, the latter showed significant shared environmental influences (.42). Fluctuations across the month were significantly heritable for both negative affect (.54) and positive affect (.34). The findings support the two-factor theory of affect, which posits that positive affect is more situational and negative affect is more dispositional. PMID:27729566

Reliability analysis of composite structures

NASA Technical Reports Server (NTRS)

Kan, Han-Pin

1992-01-01

A probabilistic static stress analysis methodology has been developed to estimate the reliability of a composite structure. Closed form stress analysis methods are the primary analytical tools used in this methodology. These structural mechanics methods are used to identify independent variables whose variations significantly affect the performance of the structure. Once these variables are identified, scatter in their values is evaluated and statistically characterized. The scatter in applied loads and the structural parameters are then fitted to appropriate probabilistic distribution functions. Numerical integration techniques are applied to compute the structural reliability. The predicted reliability accounts for scatter due to variability in material strength, applied load, fabrication and assembly processes. The influence of structural geometry and mode of failure are also considerations in the evaluation. Example problems are given to illustrate various levels of analytical complexity.

Inhibition of microbial biofuel production in drought-stressed switchgrass hydrolysate

DOE PAGES

Ong, Rebecca Garlock; Higbee, Alan; Bottoms, Scott; ...

2016-11-08

Here, interannual variability in precipitation, particularly drought, can affect lignocellulosic crop biomass yields and composition, and is expected to increase biofuel yield variability. However, the effect of precipitation on downstream fermentation processes has never been directly characterized. In order to investigate the impact of interannual climate variability on biofuel production, corn stover and switchgrass were collected during 3 years with significantly different precipitation profiles, representing a major drought year (2012) and 2 years with average precipitation for the entire season (2010 and 2013). All feedstocks were AFEX (ammonia fiber expansion)-pretreated, enzymatically hydrolyzed, and the hydrolysates separately fermented using xylose-utilizing strainsmore » of Saccharomyces cerevisiae and Zymomonas mobilis. As a result, a chemical genomics approach was also used to evaluate the growth of yeast mutants in the hydrolysates.« less

Are there meaningful individual differences in temporal inconsistency in self-reported personality?

PubMed

Soubelet, Andrea; Salthouse, Timothy A; Oishi, Shigehiro

2014-11-01

The current project had three goals. The first was to examine whether it is meaningful to refer to across-time variability in self-reported personality as an individual differences characteristic. The second was to investigate whether negative affect was associated with variability in self-reported personality, while controlling for mean levels, and correcting for measurement errors. The third goal was to examine whether variability in self-reported personality would be larger among young adults than among older adults, and whether the relation of variability with negative affect would be stronger at older ages than at younger ages. Two moderately large samples of participants completed the International Item Pool Personality questionnaire assessing the Big Five personality dimensions either twice or thrice, in addition to several measures of negative affect. Results were consistent with the hypothesis that within-person variability in self-reported personality is a meaningful individual difference characteristic. Some people exhibited greater across-time variability than others after removing measurement error, and people who showed temporal instability in one trait also exhibited temporal instability across the other four traits. However, temporal variability was not related to negative affect, and there was no evidence that either temporal variability or its association with negative affect varied with age.

Pupillary responses during lexical decisions vary with word frequency but not emotional valence.

PubMed

Kuchinke, Lars; Võ, Melissa L-H; Hofmann, Markus; Jacobs, Arthur M

2007-08-01

Pupillary responses were examined during a lexical decision task (LDT). Word frequency (high and low frequency words) and emotional valence (positive, neutral and negative words) were varied as experimental factors incidental to the subjects. Both variables significantly affected lexical decision performance and an interaction effect was observed. The behavioral results suggest that manipulating word frequency may partly account for the heterogeneous literature findings regarding emotional valence effects in the LDT. In addition, a difference between high and low frequency words was observed in the pupil data as reflected by higher peak pupil dilations for low frequency words, whereas pupillary responses to emotionally valenced words did not differ. This result was further supported by means of a principal component analysis on the pupil data, in which a late component was shown only to be affected by word frequency. Consistent with previous findings, word frequency was found to affect the resource allocation towards processing of the letter string, while emotionally valenced words tend to facilitate processing.

Discrete Emotion Effects on Lexical Decision Response Times

PubMed Central

Briesemeister, Benny B.; Kuchinke, Lars; Jacobs, Arthur M.

2011-01-01

Our knowledge about affective processes, especially concerning effects on cognitive demands like word processing, is increasing steadily. Several studies consistently document valence and arousal effects, and although there is some debate on possible interactions and different notions of valence, broad agreement on a two dimensional model of affective space has been achieved. Alternative models like the discrete emotion theory have received little interest in word recognition research so far. Using backward elimination and multiple regression analyses, we show that five discrete emotions (i.e., happiness, disgust, fear, anger and sadness) explain as much variance as two published dimensional models assuming continuous or categorical valence, with the variables happiness, disgust and fear significantly contributing to this account. Moreover, these effects even persist in an experiment with discrete emotion conditions when the stimuli are controlled for emotional valence and arousal levels. We interpret this result as evidence for discrete emotion effects in visual word recognition that cannot be explained by the two dimensional affective space account. PMID:21887307

Trust, cooperation, and equality: a psychological analysis of the formation of social capital.

PubMed

Cozzolino, Philip J

2011-06-01

Research suggests that in modern Western culture there is a positive relationship between the equality of resources and the formation of trust and cooperation, two psychological components of social capital. Two studies elucidate the psychological processes underlying that relationship. Study 1 experimentally tested the influence of resource distributions on the formation of trust and intentions to cooperate; individuals receiving a deficit of resources and a surplus of resources evidenced lower levels of social capital (i.e., trust and cooperation) than did individuals receiving equal amounts. Analyses revealed the process was affective for deficit participants and cognitive for surplus participants. Study 2 provided suggestive support for the affective-model of equality and social capital using proxy variables in the 1996 General Social Survey data set. Results suggest support for a causal path of unequal resource distributions generating affective experiences and cognitive concerns of justice, which mediate disengagement and distrust of others. ©2010 The British Psychological Society.

Discrete emotion effects on lexical decision response times.

PubMed

Briesemeister, Benny B; Kuchinke, Lars; Jacobs, Arthur M

2011-01-01

Our knowledge about affective processes, especially concerning effects on cognitive demands like word processing, is increasing steadily. Several studies consistently document valence and arousal effects, and although there is some debate on possible interactions and different notions of valence, broad agreement on a two dimensional model of affective space has been achieved. Alternative models like the discrete emotion theory have received little interest in word recognition research so far. Using backward elimination and multiple regression analyses, we show that five discrete emotions (i.e., happiness, disgust, fear, anger and sadness) explain as much variance as two published dimensional models assuming continuous or categorical valence, with the variables happiness, disgust and fear significantly contributing to this account. Moreover, these effects even persist in an experiment with discrete emotion conditions when the stimuli are controlled for emotional valence and arousal levels. We interpret this result as evidence for discrete emotion effects in visual word recognition that cannot be explained by the two dimensional affective space account.

Mental chronometry with simple linear regression.

PubMed

Chen, J Y

1997-10-01

Typically, mental chronometry is performed by means of introducing an independent variable postulated to affect selectively some stage of a presumed multistage process. However, the effect could be a global one that spreads proportionally over all stages of the process. Currently, there is no method to test this possibility although simple linear regression might serve the purpose. In the present study, the regression approach was tested with tasks (memory scanning and mental rotation) that involved a selective effect and with a task (word superiority effect) that involved a global effect, by the dominant theories. The results indicate (1) the manipulation of the size of a memory set or of angular disparity affects the intercept of the regression function that relates the times for memory scanning with different set sizes or for mental rotation with different angular disparities and (2) the manipulation of context affects the slope of the regression function that relates the times for detecting a target character under word and nonword conditions. These ratify the regression approach as a useful method for doing mental chronometry.

Challenges to a blow/fill/seal process with airborne microorganisms having different resistances to dry heat.

PubMed

Poisson, Patrick; Sinclair, Colin S; Tallentire, Alan

2006-01-01

Controlled challenges with air dispersed microorganisms having widely different resistances to dry heat, carried out on 624 BFS machine processing growth medium, have shown that higher the heat resistance, the greater the extent of vial contamination. Differences in heat resistance affected also the extent of vial contamination when parison and vial formation were knowingly manipulated through changes made to each of three process variables, provision of ballooning air, mould vacuum delay, and parison extrusion rate. The findings demonstrate that, in this investigational system, exposure of challenge micoorganisms to heat inherent in the process has a controlling influence on vial contamination, an influence that could also control microbiological risk in production environments.

Intraindividual change and variability in daily stress processes: Findings from two measurement-burst diary studies

PubMed Central

Sliwinski, Martin J.; Almeida, David M.; Smyth, Joshua; Stawski, Robert S.

2010-01-01

There is little longitudinal information on aging-related changes in emotional responses to negative events. The present manuscript examined intraindividual change and variability in the within-person coupling of daily stress and negative affect (NA) using data from two-measurement burst daily diary studies. Three main findings emerged. First, average reactivity to daily stress increased longitudinally, and this increase was evident across most the adult lifespan. Second, individual differences in emotional reactivity to daily stress exhibited long-term temporal stability, but this stability was greatest in midlife and decreased in old age. And third, reactivity to daily stress varied reliably within-persons (across-time), with individual exhibiting higher levels of reactivity during times when reporting high levels of global subject stress in previous month. Taken together, the present results emphasize the importance of modeling dynamic psychosocial and aging processes that operate across different time scales for understanding age-related changes in daily stress processes. PMID:20025399

Assessing Biobehavioural Self-Regulation and Coregulation in Early Childhood: The Parent-Child Challenge Task

PubMed Central

Lunkenheimer, Erika; Kemp, Christine J.; Lucas-Thompson, Rachel G.; Cole, Pamela M.; Albrecht, Erin C.

2016-01-01

Researchers have argued for more dynamic and contextually relevant measures of regulatory processes in interpersonal interactions. In response, we introduce and examine the effectiveness of a new task, the Parent-Child Challenge Task, designed to assess the self-regulation and coregulation of affect, goal-directed behavior, and physiology in parents and their preschoolers in response to an experimental perturbation. Concurrent and predictive validity was examined via relations with children’s externalizing behaviors. Mothers used only their words to guide their 3-year-old children to complete increasingly difficult puzzles in order to win a prize (N = 96). A challenge condition was initiated mid-way through the task with a newly introduced time limit. The challenge produced decreases in parental teaching and dyadic behavioral variability and increases in child negative affect and dyadic affective variability, measured by dynamic systems-based methods. Children rated lower on externalizing showed respiratory sinus arrhythmia (RSA) suppression in response to challenge, whereas those rated higher on externalizing showed RSA augmentation. Additionally, select task changes in affect, behavior, and physiology predicted teacher-rated externalizing behaviors four months later. Findings indicate the Parent-Child Challenge Task was effective in producing regulatory changes and suggest its utility in assessing biobehavioral self-regulation and coregulation in parents and their preschoolers. PMID:28458616

Assessing Biobehavioural Self-Regulation and Coregulation in Early Childhood: The Parent-Child Challenge Task.

PubMed

Lunkenheimer, Erika; Kemp, Christine J; Lucas-Thompson, Rachel G; Cole, Pamela M; Albrecht, Erin C

2017-01-01

Researchers have argued for more dynamic and contextually relevant measures of regulatory processes in interpersonal interactions. In response, we introduce and examine the effectiveness of a new task, the Parent-Child Challenge Task, designed to assess the self-regulation and coregulation of affect, goal-directed behavior, and physiology in parents and their preschoolers in response to an experimental perturbation. Concurrent and predictive validity was examined via relations with children's externalizing behaviors. Mothers used only their words to guide their 3-year-old children to complete increasingly difficult puzzles in order to win a prize ( N = 96). A challenge condition was initiated mid-way through the task with a newly introduced time limit. The challenge produced decreases in parental teaching and dyadic behavioral variability and increases in child negative affect and dyadic affective variability, measured by dynamic systems-based methods. Children rated lower on externalizing showed respiratory sinus arrhythmia (RSA) suppression in response to challenge, whereas those rated higher on externalizing showed RSA augmentation. Additionally, select task changes in affect, behavior, and physiology predicted teacher-rated externalizing behaviors four months later. Findings indicate the Parent-Child Challenge Task was effective in producing regulatory changes and suggest its utility in assessing biobehavioral self-regulation and coregulation in parents and their preschoolers.

Effect of fire-retardant treatment on plywood pH and the relationship of pH to strength properties

Treesearch

S. T. Lebow; J. E. Winandy

1999-01-01

This paper investigates the relationship between wood pH and the strength properties of fire-retardant-treated (FRT) plywood, as it is affected by fire-retardant (FR) formulations, processing variables, and extended high temperature exposure conditions. The objectives of this study were to (1) identify the effect of post-treatment kiln-drying temperature, followed by...

On the Process and Consequences of Job Rationing in Oregon's Declining Wood Products Industry. WRDC Discussion Paper No. 4.

ERIC Educational Resources Information Center

Stevens, Joe B.; And Others

The study of the mobility of the wood products labor force was made in response to a predicted decline in manpower needs for the wood products industry in western Oregon and western Washington. Variables affecting workers' employability and mobility were analyzed to determine the potential in Oregon for mobility within and out of the industry, the…

Coupled hydrological and biogeochemical processes controlling variability of nitrogen species in streamflow during autumn in an upland forest

Treesearch

Stephen D. Sebestyen; James B. Shanley; Elizabeth W. Boyer; Carol Kendall; Daniel H. Doctor

2014-01-01

Autumn is a season of dynamic change in forest streams of the northeastern United States due to effects of leaf fall on both hydrology and biogeochemistry. Few studies have explored how interactions of biogeochemical transformations, various nitrogen sources, and catchment flow paths affect stream nitrogen variation during autumn. To provide more information on this...

Long-term variability in the water budget and its controls in an oak-dominated temperate forest

Treesearch

Jing Xie; Ge Sun; Hou-Sen Chu; Junguo Liu; Steven G. McNulty; Asko Noormets; Ranjeet John; Zutao Ouyang; Tianshan Zha; Haitao Li; Wenbin Guan; Jiquan Chen

2014-01-01

Water availability is one of the key environmental factors that control ecosystem functions in temperate forests. Changing climate is likely to alter the ecohydrology and other ecosystem processes, which affect forest structures and functions. We constructed a multi-year water budget (2004–2010) and quantified environmental controls on an evapotranspiration (ET) in a...

Co-evolution of Climate, Soil, and Vegetation and their interplay with Hydrological Partitioning at the Catchment Scale

NASA Astrophysics Data System (ADS)

Zapata-Rios, X.; Brooks, P. D.; Troch, P. A. A.; McIntosh, J. C.

2014-12-01

Landscape, climate, and vegetation interactions play a fundamental role in controlling the distribution of available water in hillslopes and catchments. In mid-latitudes, terrain aspect can regulate surface and subsurface hydrological processes, which not only affect the partitioning of energy and precipitation on short time scales, but also soil development, vegetation characteristics on long time scales. In Redondo Peak in northern New Mexico, a volcanic resurgent dome, first order streams drain different slopes around the mountain. In this setting, we study three adjacent first order catchments that share similar physical characteristics, but drain different aspects, allowing for an empirical study of how topographically controlled microclimate and soil influence the integrated hydrological and vegetation response. From 2008 to 2012, catchments were compared for the way they partition precipitation and how vegetation responds to variable water fluxes. Meteorological variables were monitored in 5 stations around Redondo Peak and surface runoff was monitored at the catchments' outlets. Hydrological partitioning at the catchment scale was estimated with the Horton Index, defined as the ratio between vaporization and wetting and it represents a measure of catchment-scale vegetation water use. Vegetation response was estimated using remotely sensed vegetation greenness (NDVI) derived from MODIS every 16 days with a spatial resolution of 250 m. Results show that the predominantly north facing catchment has the largest and least variable baseflow and discharge, consistent with greater mineral weathering fluxes and longer water transit times. In addition, vaporization, wetting and Horton Index, as well as NDVI, are smaller in the north facing catchment compared to the south east facing catchments. The predominant terrain aspect controls soil development, which affects the partitioning of precipitation and vegetation response at the catchment scale. These results also demonstrate how landscape evolution (e.g. depth of weathering profile) can affect various hydrologic processes, including streamflow response to precipitation and water residence time. In turn these processes are first-order controls on the sensitivity of the landscape to land use and climate change.

Short-term rainfall: its scaling properties over Portugal

NASA Astrophysics Data System (ADS)

de Lima, M. Isabel P.

2010-05-01

The characterization of rainfall at a variety of space- and time-scales demands usually that data from different origins and resolution are explored. Different tools and methodologies can be used for this purpose. In regions where the spatial variation of rain is marked, the study of the scaling structure of rainfall can lead to a better understanding of the type of events affecting that specific area, which is essential for many engineering applications. The relevant factors affecting rain variability, in time and space, can lead to contrasting statistics which should be carefully taken into account in design procedures and decision making processes. One such region is Mainland Portugal; the territory is located in the transitional region between the sub-tropical anticyclone and the subpolar depression zones and is characterized by strong north-south and east-west rainfall gradients. The spatial distribution and seasonal variability of rain are particularly influenced by the characteristics of the global circulation. One specific feature is the Atlantic origin of many synoptic disturbances in the context of the regional geography (e.g. latitude, orography, oceanic and continental influences). Thus, aiming at investigating the statistical signature of rain events of different origins, resulting from the large number of mechanisms and factors affecting the rainfall climate over Portugal, scale-invariant analyses of the temporal structure of rain from several locations in mainland Portugal were conducted. The study used short-term rainfall time series. Relevant scaling ranges were identified and characterized that help clarifying the small-scale behaviour and statistics of this process.

An Informatics Based Approach to Reduce the Grain Size of Cast Hadfield Steel

NASA Astrophysics Data System (ADS)

Dey, Swati; Pathak, Shankha; Sheoran, Sumit; Kela, Damodar H.; Datta, Shubhabrata

2016-04-01

Materials Informatics concept using computational intelligence based approaches are employed to bring out the significant alloying additions to achieve grain refinement in cast Hadfield steel. Castings of Hadfield steels used for railway crossings, requires fine grained austenitic structure. Maintaining proper grain size of this component is very crucial in order to achieve the desired properties and service life. This work studies the important variables affecting the grain size of such steels which includes the compositional and processing variables. The computational findings and prior knowledge is used to design the alloy, which is subjected to a few trials to validate the findings.

Why do Tornados and Hail Storms Rest on Weekends?

NASA Technical Reports Server (NTRS)

Rosenfeld, Daniel; Bell, Thomas L.

2010-01-01

When anthropogenic aerosols over the eastern USA during summertime are at their weekly mid-week peak, tornado and hail storm activity there is also near its weekly maximum. The weekly cycle in storm activity is statistically significant and unlikely to be due to natural variability. The pattern of variability supports the hypothesis that air pollution aerosols invigorate deep convective clouds in a moist, unstable atmosphere, to the extent of inducing production of large hailstones and tornados. This is caused by the effect of aerosols on cloud-drop nucleation, making cloud drops smaller, delaying precipitation-forming processes and their evaporation, and hence affecting cloud dynamics.

Dryland ecosystem responses to precipitation extremes and wildfire at a long-term rainfall manipulation experiment

NASA Astrophysics Data System (ADS)

Brown, R. F.; Collins, S. L.

2017-12-01

Climate is becoming increasingly more variable due to global environmental change, which is evidenced by fewer, but more extreme precipitation events, changes in precipitation seasonality, and longer, higher severity droughts. These changes, combined with a rising incidence of wildfire, have the potential to strongly impact net primary production (NPP) and key biogeochemical cycles, particularly in dryland ecosystems where NPP is sequentially limited by water and nutrient availability. Here we utilize a ten-year dataset from an ongoing long-term field experiment established in 2007 in which we experimentally altered monsoon rainfall variability to examine how our manipulations, along with naturally occurring events, affect NPP and associated biogeochemical cycles in a semi-arid grassland in central New Mexico, USA. Using long-term regional averages, we identified extremely wet monsoon years (242.8 mm, 2013), and extremely dry monsoon years (86.0 mm, 2011; 80.0 mm, 2015) and water years (117.0 mm, 2011). We examined how changes in precipitation variability and extreme events affected ecosystem processes and function particularly in the context of ecosystem recovery following a 2009 wildfire. Response variables included above- and below-ground plant biomass (ANPP & BNPP) and abundance, soil nitrogen availability, and soil CO2 efflux. Mean ANPP ranged from 3.6 g m-2 in 2011 to 254.5 g m-2 in 2013, while BNPP ranged from 23.5 g m-2 in 2015 to 194.2 g m-2 in 2013, demonstrating NPP in our semi-arid grassland is directly linked to extremes in both seasonal and annual precipitation. We also show increased nitrogen deposition positively affects NPP in unburned grassland, but has no significant impact on NPP post-fire except during extremely wet monsoon years. While soil respiration rates reflect lower ANPP post-fire, patterns in CO2 efflux have not been shown to change significantly in that efflux is greatest following large precipitation events preceded by longer drying periods. Current land surface models poorly represent dryland ecosystems, which frequently undergo extreme weather events. Our long-term experiment provides key insights into ecosystem processes and function, thereby providing capacity for model improvement particularly in the context of future environmental change.

Variables affecting learning in a simulation experience: a mixed methods study.

PubMed

Beischel, Kelly P

2013-02-01

The primary purpose of this study was to test a hypothesized model describing the direct effects of learning variables on anxiety and cognitive learning outcomes in a high-fidelity simulation (HFS) experience. The secondary purpose was to explain and explore student perceptions concerning the qualities and context of HFS affecting anxiety and learning. This study used a mixed methods quantitative-dominant explanatory design with concurrent qualitative data collection to examine variables affecting learning in undergraduate, beginning nursing students (N = 124). Being ready to learn, having a strong auditory-verbal learning style, and being prepared for simulation directly affected anxiety, whereas learning outcomes were directly affected by having strong auditory-verbal and hands-on learning styles. Anxiety did not quantitatively mediate cognitive learning outcomes as theorized, although students qualitatively reported debilitating levels of anxiety. This study advances nursing education science by providing evidence concerning variables affecting learning outcomes in HFS.

Extrusion-spheronization: process variables and characterization.

PubMed

Sinha, V R; Agrawal, M K; Agarwal, A; Singh, G; Ghai, D

2009-01-01

Multiparticulate systems have undergone great development in the past decade fueled by the better understanding of their multiple roles as a suitable delivery system. With the passage of time, significant advances have been made in the process of pelletization due to the incorporation of specialized techniques for their development. Extrusion-spheronization seems to be the most promising process for the optimum delivery of many potent drugs having high systemic toxicity. It also offers immense pharmaceutical applicability due to the benefits of high loading capacity of active ingredient(s), narrow size distribution, and cost-effectiveness. On application of a specific coat, these systems can also aid in site-specific delivery, thereby enhancing the bioavailability of many drugs. The current review focuses on the process of extrusion-spheronization and the operational (extruder types, screen pressure, screw speed, temperature, moisture content, spheronization load, speed and time) and formulation (excipients and drugs) variables, which may affect the quality of the final pellets. Various methods for the evaluation of the quality of the pellets with regard to the size distribution, shape, friability, granule strength, density, porosity, flow properties, and surface texture are discussed.

Utilizing multiple state variables to improve the dynamic range of analog switching in a memristor

NASA Astrophysics Data System (ADS)

Jeong, YeonJoo; Kim, Sungho; Lu, Wei D.

2015-10-01

Memristors and memristive systems have been extensively studied for data storage and computing applications such as neuromorphic systems. To act as synapses in neuromorphic systems, the memristor needs to exhibit analog resistive switching (RS) behavior with incremental conductance change. In this study, we show that the dynamic range of the analog RS behavior can be significantly enhanced in a tantalum-oxide-based memristor. By controlling different state variables enabled by different physical effects during the RS process, the gradual filament expansion stage can be selectively enhanced without strongly affecting the abrupt filament length growth stage. Detailed physics-based modeling further verified the observed experimental effects and revealed the roles of oxygen vacancy drift and diffusion processes, and how the diffusion process can be selectively enhanced during the filament expansion stage. These findings lead to more desirable and reliable memristor behaviors for analog computing applications. Additionally, the ability to selectively control different internal physical processes demonstrated in the current study provides guidance for continued device optimization of memristor devices in general.

Supercritical fluid extraction of ginger (Zingiber Officinale Var. Amarum) : Global yield and composition study

NASA Astrophysics Data System (ADS)

Fitriady, Muhammad Arifuddin; Sulaswatty, Anny; Agustian, Egi; Salahuddin, Aditama, Deska Prayoga Fauzi

2017-11-01

An experiment to observe the effect of temperature and time process in ginger rhizome-Supercritical Fluid Extraction (SFE) using CO2 as the solvent has been conducted. The ginger rhizome (Zingiber Officinale Var. Amarum) was washed, drained, sliced, sun-dried, and then stored in a sealed bag prior to usage. The temperature and time process variables are each 35, 40, 45°C and 2, 4, 6 hours respectively with the pressure variable are 3500, 4000, and 4500 psi. It is found that the highest yield (2.9%) was achieved using temperature of 40°C and pressure of 4500 psiwith the process time of 4 hours. However, using the curve-fitting method, it is suggested to use 42°C as the temperature and 5 hours, 7 minutes, and 30 seconds (5.125 Hours) as the time process to obtain the highest yield. The temperature changes will affect both solvent and vapor pressure of diluted compounds of the ginger which will influence the global yield and the composition of the extract. The three major components of the extract are curcumene, zingiberene, and β - sesquipellandrene,

Depressed mood, positive affect, and heart rate variability in patients with suspected coronary artery disease.

PubMed

Bhattacharyya, Mimi R; Whitehead, Daisy L; Rakhit, Roby; Steptoe, Andrew

2008-11-01

To test associations between heart rate variability (HRV), depressed mood, and positive affect in patients with suspected coronary artery disease (CAD). Depression is associated with impaired HRV post acute cardiac events, but evidence in patients with stable coronary artery disease (CAD) is inconsistent. Seventy-six patients (52 men, 24 women; mean age = 61.1 years) being investigated for suspected CAD on the basis of symptomatology and positive noninvasive tests, completed 24-hour electrocardiograms. The Beck Depression Inventory (BDI) was administered, and positive and depressed affect was measured over the study period with the Day Reconstruction Method (DRM). A total of 46 (60.5%) patients were later found to have definite CAD. HRV was analyzed, using spectral analysis. Typical diurnal profiles of HRV were observed, with greater normalized high frequency (HF) and lower normalized low frequency (LF) power in the night compared with the day. BDI depression scores were not consistently associated with HRV. But positive affect was associated with greater normalized HF power (p = .039) and reduced normalized LF power (p = .007) independently of age, gender, medication with beta blockers, CAD status, body mass index, smoking, and habitual physical activity level. In patients with definite CAD, depressed affect assessed using the DRM was associated with reduced normalized HF power and heightened normalized LF power (p = .007) independently of covariates. Relationships between depression and HRV in patients with CAD may depend on affective experience over the monitoring period. Enhanced parasympathetic cardiac control may be a process through which positive affect protects against cardiovascular disease.

Does Encope emarginata (Echinodermata: Echinoidea) affect spatial variation patterns of estuarine subtidal meiofauna and microphytobenthos?

NASA Astrophysics Data System (ADS)

Brustolin, Marco C.; Thomas, Micheli C.; Mafra, Luiz L.; Lana, Paulo da Cunha

2014-08-01

Foraging macrofauna, such as the sand dollar Encope emarginata, can modify sediment properties and affect spatial distribution patterns of microphytobenthos and meiobenthos at different spatial scales. We adopted a spatial hierarchical approach composed of five spatial levels (km, 100 s m, 10 s m, 1 s m and cm) to describe variation patterns of microphytobenthos, meiobenthos and sediment variables in shallow subtidal regions in the subtropical Paranaguá Bay (Southern Brazil) with live E. emarginata (LE), dead E. emarginata (only skeletons - (DE), and no E. emarginata (WE). The overall structure of microphytobenthos and meiofauna was always less variable at WE and much of variation at the scale of 100 s m was related to variability within LE and DE, due to foraging activities or to the presence of shell hashes. Likewise, increased variability in chlorophyll-a and phaeopigment contents was observed among locations within LE, although textural parameters of sediment varied mainly at smaller scales. Variations within LE were related to changes on the amount and quality of food as a function of sediment heterogeneity induced by the foraging behavior of sand dollars. We provide strong evidence that top-down effects related to the occurrence of E. emarginata act in synergy with bottom-up structuring related to hydrodynamic processes in determining overall benthic spatial variability. Conversely, species richness is mainly influenced by environmental heterogeneity at small spatial scales (centimeters to meters), which creates a mosaic of microhabitats.

Analysis of Salmonella sp bacterial contamination on Vannamei Shrimp using binary logit model approach

NASA Astrophysics Data System (ADS)

Oktaviana, P. P.; Fithriasari, K.

2018-04-01

Mostly Indonesian citizen consume vannamei shrimp as their food. Vannamei shrimp also is one of Indonesian exports comodities mainstay. Vannamei shrimp in the ponds and markets could be contaminated by Salmonella sp bacteria. This bacteria will endanger human health. Salmonella sp bacterial contamination on vannamei shrimp could be affected by many factors. This study is intended to identify what factors that supposedly influence the Salmonella sp bacterial contamination on vannamei shrimp. The researchers used the testing result of Salmonella sp bacterial contamination on vannamei shrimp as response variable. This response variable has two categories: 0 = if testing result indicate that there is no Salmonella sp on vannamei shrimp; 1 = if testing result indicate that there is Salmonella sp on vannamei shrimp. There are four factors that supposedly influence the Salmonella sp bacterial contamination on vannamei shrimp, which are the testing result of Salmonella sp bacterial contamination on farmer hand swab; the subdistrict of vannamei shrimp ponds; the fish processing unit supplied by; and the pond are in hectare. This four factors used as predictor variables. The analysis used is Binary Logit Model Approach according to the response variable that has two categories. The analysis result indicates that the factors or predictor variables which is significantly affect the Salmonella sp bacterial contamination on vannamei shrimp are the testing result of Salmonella sp bacterial contamination on farmer hand swab and the subdistrict of vannamei shrimp ponds.

Feeling old today? Daily health, stressors, and affect explain day-to-day variability in subjective age.

PubMed

Kotter-Grühn, Dana; Neupert, Shevaun D; Stephan, Yannick

2015-01-01

Subjective age is an important correlate of health, well-being, and longevity. So far, little is known about short-term variability in subjective age and the circumstances under which individuals feel younger/older in daily life. This study examined whether (a) older adults' felt age fluctuates on a day-to-day basis, (b) daily changes in health, stressors, and affect explain fluctuations in felt age, and (c) the daily associations between felt age and health, stressors, or affect are time-ordered. Using an eight-day daily diary approach, N = 43 adults (60-96 years, M = 74.65, SD = 8.19) filled out daily questionnaires assessing subjective age, health, daily stressors, and affect. Data were analysed using multilevel modelling. Subjective age, health, daily stressors, affect. Intra-individual variability in felt age was not explained by time but by short-term variability in other variables. Specifically, on days when participants experienced more than average health problems, stress, or negative affect they felt older than on days with average health, stress, or negative affect. No time-ordered effects were found. Bad health, many stressors, and negative affective experiences constitute circumstances under which older adults feel older than they typically do. Thus, daily measures of subjective age could be markers of health and well-being.

Large herbivores affect forest ecosystem functions by altering the structure of dung beetle communities

NASA Astrophysics Data System (ADS)

Iida, Taichi; Soga, Masashi; Koike, Shinsuke

2018-04-01

Dramatic increases in populations of large mammalian herbivores have become a major ecological issue, particularly in the northern hemisphere, due to their substantial impacts on both animal and plant communities through processes such as grazing, browsing, and trampling. However, little is known about the consequences of these population explosions on ecosystem functions. Here, we experimentally investigated how the population density of sika deer (Cervus nippon) in temperate deciduous forest areas in Japan affected the decomposition of mammal dung by dung beetles, which is a key process in forest ecosystems. We measured a range of environmental variables (e.g., vegetation cover, soil hardness) and the dung decomposition rate, measured as the amount of deer dung decomposed during one week, and sampled dung beetles at 16 study sites with three different deer densities (high/intermediate/low). We then used structural equation modeling to investigate the relationships between deer density, environmental variables, the biomass of dung beetles (classified into small or large species), and the dung decomposition rate. We found that the biomass of small species increased with increasing deer density, whereas that of large species was not related to deer density. Furthermore, the dung decomposition rate was positively related to the biomass of small species but unrelated to that of large species. Overall, our results showed that an increase in deer density affects the decomposition rate of mammal dung by changing the structure of dung beetle communities (i.e., increasing the number of small dung beetles). Such an understanding of how increases in large herbivore populations affect ecosystem functions is important for accurately evaluating the ecological consequences of their overabundance and ultimately managing their populations appropriately.

Understanding interannual variability in the distribution of, and transport processes affecting, the early life stages of Todarodes pacificus using behavioral-hydrodynamic modeling approaches

NASA Astrophysics Data System (ADS)

Kim, Jung Jin; Stockhausen, William; Kim, Suam; Cho, Yang-Ki; Seo, Gwang-Ho; Lee, Joon-Soo

2015-11-01

To understand interannual variability in the distribution of the early life stages of Todarodes pacificus summer spawning population, and to identify the key transport processes influencing this variability, we used a coupled bio-physical model that combines an individual-based model (IBM) incorporating ontogenetic vertical migration for paralarval behavior and temperature-dependent survival process with a ROMS oceanographic model. Using the distribution of paralarvae observed in the northern East China Sea (ECS) during several field cruises as an end point, the spawning ground for the summer-spawning population was estimated to extend from southeast Jeju Island to the central ECS near 29°N by running the model backwards in time. Running the model forward, interannual variability in the distribution of paralarvae predicted by the model was consistent with that observed in several field surveys; surviving individuals in the northern ECS were substantially more abundant in late July 2006 than in 2007, in agreement with observed paralarval distributions. The total number of surviving individuals at 60 days after release based on the simulation throughout summer spawning period (June-August) was 20,329 for 2006, compared with 13,816 for 2007. The surviving individuals were mainly distributed in the East/Japan Sea (EJS), corresponding to a pathway following the nearshore branch of the Tsushima Warm Current flowing along the Japanese coast during both years. In contrast, the abundance of surviving individuals was extremely low in 2007 compared to 2006 on the Pacific side of Japan. Interannual variability in transport and survival processes made a substantial impact on not only the abundance of surviving paralarvae, but also on the flux of paralarvae to adjacent waters. Our simulation results for between-year variation in paralarval abundance coincide with recruitment (year n + 1) variability of T. pacificus in the field. The agreement between the simulation and field data indicates our model may be useful for predicting the recruitment of T. pacificus.

Bio-inspired online variable recruitment control of fluidic artificial muscles

NASA Astrophysics Data System (ADS)

Jenkins, Tyler E.; Chapman, Edward M.; Bryant, Matthew

2016-12-01

This paper details the creation of a hybrid variable recruitment control scheme for fluidic artificial muscle (FAM) actuators with an emphasis on maximizing system efficiency and switching control performance. Variable recruitment is the process of altering a system’s active number of actuators, allowing operation in distinct force regimes. Previously, FAM variable recruitment was only quantified with offline, manual valve switching; this study addresses the creation and characterization of novel, on-line FAM switching control algorithms. The bio-inspired algorithms are implemented in conjunction with a PID and model-based controller, and applied to a simulated plant model. Variable recruitment transition effects and chatter rejection are explored via a sensitivity analysis, allowing a system designer to weigh tradeoffs in actuator modeling, algorithm choice, and necessary hardware. Variable recruitment is further developed through simulation of a robotic arm tracking a variety of spline position inputs, requiring several levels of actuator recruitment. Switching controller performance is quantified and compared with baseline systems lacking variable recruitment. The work extends current variable recruitment knowledge by creating novel online variable recruitment control schemes, and exploring how online actuator recruitment affects system efficiency and control performance. Key topics associated with implementing a variable recruitment scheme, including the effects of modeling inaccuracies, hardware considerations, and switching transition concerns are also addressed.

Environmental variability and population dynamics: Do European and North American ducks play by the same rules?

USGS Publications Warehouse

Pöysä, Hannu; Rintala, Jukka; Johnson, Douglas H.; Kauppinen, Jukka; Lammi, Esa; Nudds, Thomas D.; Väänänen, Veli-Matti

2016-01-01

Density dependence, population regulation, and variability in population size are fundamental population processes, the manifestation and interrelationships of which are affected by environmental variability. However, there are surprisingly few empirical studies that distinguish the effect of environmental variability from the effects of population processes. We took advantage of a unique system, in which populations of the same duck species or close ecological counterparts live in highly variable (north American prairies) and in stable (north European lakes) environments, to distinguish the relative contributions of environmental variability (measured as between-year fluctuations in wetland numbers) and intraspecific interactions (density dependence) in driving population dynamics. We tested whether populations living in stable environments (in northern Europe) were more strongly governed by density dependence than populations living in variable environments (in North America). We also addressed whether relative population dynamical responses to environmental variability versus density corresponded to differences in life history strategies between dabbling (relatively “fast species” and governed by environmental variability) and diving (relatively “slow species” and governed by density) ducks. As expected, the variance component of population fluctuations caused by changes in breeding environments was greater in North America than in Europe. Contrary to expectations, however, populations in more stable environments were not less variable nor clearly more strongly density dependent than populations in highly variable environments. Also, contrary to expectations, populations of diving ducks were neither more stable nor stronger density dependent than populations of dabbling ducks, and the effect of environmental variability on population dynamics was greater in diving than in dabbling ducks. In general, irrespective of continent and species life history, environmental variability contributed more to variation in species abundances than did density. Our findings underscore the need for more studies on populations of the same species in different environments to verify the generality of current explanations about population dynamics and its association with species life history.

Environmental variability and population dynamics: do European and North American ducks play by the same rules?

PubMed

Pöysä, Hannu; Rintala, Jukka; Johnson, Douglas H; Kauppinen, Jukka; Lammi, Esa; Nudds, Thomas D; Väänänen, Veli-Matti

2016-10-01

Density dependence, population regulation, and variability in population size are fundamental population processes, the manifestation and interrelationships of which are affected by environmental variability. However, there are surprisingly few empirical studies that distinguish the effect of environmental variability from the effects of population processes. We took advantage of a unique system, in which populations of the same duck species or close ecological counterparts live in highly variable (north American prairies) and in stable (north European lakes) environments, to distinguish the relative contributions of environmental variability (measured as between-year fluctuations in wetland numbers) and intraspecific interactions (density dependence) in driving population dynamics. We tested whether populations living in stable environments (in northern Europe) were more strongly governed by density dependence than populations living in variable environments (in North America). We also addressed whether relative population dynamical responses to environmental variability versus density corresponded to differences in life history strategies between dabbling (relatively "fast species" and governed by environmental variability) and diving (relatively "slow species" and governed by density) ducks. As expected, the variance component of population fluctuations caused by changes in breeding environments was greater in North America than in Europe. Contrary to expectations, however, populations in more stable environments were not less variable nor clearly more strongly density dependent than populations in highly variable environments. Also, contrary to expectations, populations of diving ducks were neither more stable nor stronger density dependent than populations of dabbling ducks, and the effect of environmental variability on population dynamics was greater in diving than in dabbling ducks. In general, irrespective of continent and species life history, environmental variability contributed more to variation in species abundances than did density. Our findings underscore the need for more studies on populations of the same species in different environments to verify the generality of current explanations about population dynamics and its association with species life history.

Affective Factors in the Mediation of Background Effects on Cognitive Performance.

ERIC Educational Resources Information Center

Cuttance, Peter F.

1980-01-01

Academic achievement at age 16 was influenced more by achievement at age 14 than by affective variables. Affective variables included academic and occupational aspiration, parent expectations, school attitudes, sex, socioeconomic status, parents' education, and migrancy. (CP)

Communication and Organization in Software Development: An Empirical Study

NASA Technical Reports Server (NTRS)

Seaman, Carolyn B.; Basili, Victor R.

1996-01-01

The empirical study described in this paper addresses the issue of communication among members of a software development organization. The independent variables are various attributes of organizational structure. The dependent variable is the effort spent on sharing information which is required by the software development process in use. The research questions upon which the study is based ask whether or not these attributes of organizational structure have an effect on the amount of communication effort expended. In addition, there are a number of blocking variables which have been identified. These are used to account for factors other than organizational structure which may have an effect on communication effort. The study uses both quantitative and qualitative methods for data collection and analysis. These methods include participant observation, structured interviews, and graphical data presentation. The results of this study indicate that several attributes of organizational structure do affect communication effort, but not in a simple, straightforward way. In particular, the distances between communicators in the reporting structure of the organization, as well as in the physical layout of offices, affects how quickly they can share needed information, especially during meetings. These results provide a better understanding of how organizational structure helps or hinders communication in software development.

Reduction of tablet weight variability by optimizing paddle speed in the forced feeder of a high-speed rotary tablet press.

PubMed

Peeters, Elisabeth; De Beer, Thomas; Vervaet, Chris; Remon, Jean-Paul

2015-04-01

Tableting is a complex process due to the large number of process parameters that can be varied. Knowledge and understanding of the influence of these parameters on the final product quality is of great importance for the industry, allowing economic efficiency and parametric release. The aim of this study was to investigate the influence of paddle speeds and fill depth at different tableting speeds on the weight and weight variability of tablets. Two excipients possessing different flow behavior, microcrystalline cellulose (MCC) and dibasic calcium phosphate dihydrate (DCP), were selected as model powders. Tablets were manufactured via a high-speed rotary tablet press using design of experiments (DoE). During each experiment also the volume of powder in the forced feeder was measured. Analysis of the DoE revealed that paddle speeds are of minor importance for tablet weight but significantly affect volume of powder inside the feeder in case of powders with excellent flowability (DCP). The opposite effect of paddle speed was observed for fairly flowing powders (MCC). Tableting speed played a role in weight and weight variability, whereas changing fill depth exclusively influenced tablet weight. The DoE approach allowed predicting the optimum combination of process parameters leading to minimum tablet weight variability. Monte Carlo simulations allowed assessing the probability to exceed the acceptable response limits if factor settings were varied around their optimum. This multi-dimensional combination and interaction of input variables leading to response criteria with acceptable probability reflected the design space.

Variables affecting the quantitation of CD22 in neoplastic B cells.

PubMed

Jasper, Gregory A; Arun, Indu; Venzon, David; Kreitman, Robert J; Wayne, Alan S; Yuan, Constance M; Marti, Gerald E; Stetler-Stevenson, Maryalice

2011-03-01

Quantitative flow cytometry (QFCM) is being applied in the clinical flow cytometry laboratory for diagnosis, prognosis, and assessment of patients receiving antibody-based therapy. ABC values and the effect of technical variables on CD22 quantitation in acute lymphoblastic leukemia (ALL), chronic lymphocytic leukemia (CLL), mantle cell lymphoma (MCL), follicular lymphoma (FCL), hairy cell leukemia (HCL) and normal B cells were studied. The QuantiBrite System® was used to determine the level of CD22 expression (mean antibody bound per cell, ABC) by malignant and normal B cells. The intra-assay variability, number of cells required for precision, effect of delayed processing as well as shipment of peripheral blood specimens (delayed processing and exposure to noncontrolled environments), and the effect of paraformaldehyde fixation on assay results were studied. The QuantiBRITE method of measuring CD22 ABC is precise (median CV 1.6%, 95% confidence interval, 1.2-2.3%) but a threshold of 250 malignant cells is required for reliable CD22 ABC values. Delayed processing and overnight shipment of specimens resulted in significantly different ABC values whereas fixation for up to 12 h had no significant effect. ABC measurements determined that CD22 expression is lower than normal in ALL, CLL, FCL, and MCL but higher than normal in HCL. CD22 expression was atypical in the hematolymphoid malignancies studied and may have diagnostic utility. Technical variables such as cell number analyzed and delayed processing or overnight shipment of specimens impact significantly on the measurement of antigen expression by QFCM in the clinical laboratory. Published 2010 Wiley-Liss, Inc.

A data-driven approach to identify controls on global fire activity from satellite and climate observations (SOFIA V1)

NASA Astrophysics Data System (ADS)

Forkel, Matthias; Dorigo, Wouter; Lasslop, Gitta; Teubner, Irene; Chuvieco, Emilio; Thonicke, Kirsten

2017-12-01

Vegetation fires affect human infrastructures, ecosystems, global vegetation distribution, and atmospheric composition. However, the climatic, environmental, and socioeconomic factors that control global fire activity in vegetation are only poorly understood, and in various complexities and formulations are represented in global process-oriented vegetation-fire models. Data-driven model approaches such as machine learning algorithms have successfully been used to identify and better understand controlling factors for fire activity. However, such machine learning models cannot be easily adapted or even implemented within process-oriented global vegetation-fire models. To overcome this gap between machine learning-based approaches and process-oriented global fire models, we introduce a new flexible data-driven fire modelling approach here (Satellite Observations to predict FIre Activity, SOFIA approach version 1). SOFIA models can use several predictor variables and functional relationships to estimate burned area that can be easily adapted with more complex process-oriented vegetation-fire models. We created an ensemble of SOFIA models to test the importance of several predictor variables. SOFIA models result in the highest performance in predicting burned area if they account for a direct restriction of fire activity under wet conditions and if they include a land cover-dependent restriction or allowance of fire activity by vegetation density and biomass. The use of vegetation optical depth data from microwave satellite observations, a proxy for vegetation biomass and water content, reaches higher model performance than commonly used vegetation variables from optical sensors. We further analyse spatial patterns of the sensitivity between anthropogenic, climate, and vegetation predictor variables and burned area. We finally discuss how multiple observational datasets on climate, hydrological, vegetation, and socioeconomic variables together with data-driven modelling and model-data integration approaches can guide the future development of global process-oriented vegetation-fire models.

Interannual variation of carbon fluxes from three contrasting evergreen forests: the role of forest dynamics and climate.

PubMed

Sierra, Carlos A; Loescher, Henry W; Harmon, Mark E; Richardson, Andrew D; Hollinger, David Y; Perakis, Steven S

2009-10-01

Interannual variation of carbon fluxes can be attributed to a number of biotic and abiotic controls that operate at different spatial and temporal scales. Type and frequency of disturbance, forest dynamics, and climate regimes are important sources of variability. Assessing the variability of carbon fluxes from these specific sources can enhance the interpretation of past and current observations. Being able to separate the variability caused by forest dynamics from that induced by climate will also give us the ability to determine if the current observed carbon fluxes are within an expected range or whether the ecosystem is undergoing unexpected change. Sources of interannual variation in ecosystem carbon fluxes from three evergreen ecosystems, a tropical, a temperate coniferous, and a boreal forest, were explored using the simulation model STANDCARB. We identified key processes that introduced variation in annual fluxes, but their relative importance differed among the ecosystems studied. In the tropical site, intrinsic forest dynamics contributed approximately 30% of the total variation in annual carbon fluxes. In the temperate and boreal sites, where many forest processes occur over longer temporal scales than those at the tropical site, climate controlled more of the variation among annual fluxes. These results suggest that climate-related variability affects the rates of carbon exchange differently among sites. Simulations in which temperature, precipitation, and radiation varied from year to year (based on historical records of climate variation) had less net carbon stores than simulations in which these variables were held constant (based on historical records of monthly average climate), a result caused by the functional relationship between temperature and respiration. This suggests that, under a more variable temperature regime, large respiratory pulses may become more frequent and high enough to cause a reduction in ecosystem carbon stores. Our results also show that the variation of annual carbon fluxes poses an important challenge in our ability to determine whether an ecosystem is a source, a sink, or is neutral in regard to CO2 at longer timescales. In simulations where climate change negatively affected ecosystem carbon stores, there was a 20% chance of committing Type II error, even with 20 years of sequential data.

Multivariate evaluation of the cutting performance of rotary instruments with electric and air-turbine handpieces.

PubMed

Funkenbusch, Paul D; Rotella, Mario; Chochlidakis, Konstantinos; Ercoli, Carlo

2016-10-01

Laboratory studies of tooth preparation often involve single values for all variables other than the one being tested. In contrast, in clinical settings, not all variables can be adequately controlled. For example, a new dental rotary cutting instrument may be tested in the laboratory by making a specific cut with a fixed force, but, in clinical practice, the instrument must make different cuts with individual dentists applying different forces. Therefore, the broad applicability of laboratory results to diverse clinical conditions is uncertain and the comparison of effects across studies difficult. The purpose of this in vitro study was to examine the effects of 9 process variables on the dental cutting of rotary cutting instruments used with an electric handpiece and compare them with those of a previous study that used an air-turbine handpiece. The effects of 9 key process variables on the efficiency of a simulated dental cutting operation were measured. A fractional factorial experiment was conducted by using an electric handpiece in a computer-controlled, dedicated testing apparatus to simulate dental cutting procedures with Macor blocks as the cutting substrate. Analysis of variance (ANOVA) was used to assess the statistical significance (α=.05). Four variables (targeted applied load, cut length, diamond grit size, and cut type) consistently produced large, statistically significant effects, whereas 5 variables (rotation per minute, number of cooling ports, rotary cutting instrument diameter, disposability, and water flow rate) produced relatively small, statistically insignificant effects. These results are generally similar to those previously found for an air-turbine handpiece. Regardless of whether an electric or air-turbine handpiece was used, the control exerted by the dentist, simulated in this study by targeting a specific level of applied force, was the single most important factor affecting cutting efficiency. Cutting efficiency was also significantly affected by factors simulating patient/clinical circumstances and hardware choices. These results highlight the greater importance of local clinical conditions (procedure, dentist) in understanding dental cutting as opposed to other hardware-related factors. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

An Ecological Alternative to Snodgrass & Vanderwart: 360 High Quality Colour Images with Norms for Seven Psycholinguistic Variables

PubMed Central

Moreno-Martínez, Francisco Javier; Montoro, Pedro R.

2012-01-01

This work presents a new set of 360 high quality colour images belonging to 23 semantic subcategories. Two hundred and thirty-six Spanish speakers named the items and also provided data from seven relevant psycholinguistic variables: age of acquisition, familiarity, manipulability, name agreement, typicality and visual complexity. Furthermore, we also present lexical frequency data derived from Internet search hits. Apart from the high number of variables evaluated, knowing that it affects the processing of stimuli, this new set presents important advantages over other similar image corpi: (a) this corpus presents a broad number of subcategories and images; for example, this will permit researchers to select stimuli of appropriate difficulty as required, (e.g., to deal with problems derived from ceiling effects); (b) the fact of using coloured stimuli provides a more realistic, ecologically-valid, representation of real life objects. In sum, this set of stimuli provides a useful tool for research on visual object-and word- processing, both in neurological patients and in healthy controls. PMID:22662166

How does spatial variability of climate affect catchment streamflow predictions?

EPA Science Inventory

Spatial variability of climate can negatively affect catchment streamflow predictions if it is not explicitly accounted for in hydrologic models. In this paper, we examine the changes in streamflow predictability when a hydrologic model is run with spatially variable (distribute...

Identification and statistical optimization of fermentation conditions for a newly isolated extracellular cholesterol oxidase-producing Streptomyces cavourensis strain NEAE-42.

PubMed

El-Naggar, Noura El-Ahmady; El-Shweihy, Nancy M; El-Ewasy, Sara M

2016-09-20

Due to broad range of clinical and industrial applications of cholesterol oxidase, isolation and screening of bacterial strains producing extracellular form of cholesterol oxidase is of great importance. One hundred and thirty actinomycete isolates were screened for their cholesterol oxidase activity. Among them, a potential culture, strain NEAE-42 is displayed the highest extracellular cholesterol oxidase activity. It was selected and identified as Streptomyces cavourensis strain NEAE-42. The optimization of different process parameters for cholesterol oxidase production by Streptomyces cavourensis strain NEAE-42 using Plackett-Burman experimental design and response surface methodology was carried out. Fifteen variables were screened using Plackett-Burman experimental design. Cholesterol, initial pH and (NH4)2SO4 were the most significant positive independent variables affecting cholesterol oxidase production. Central composite design was chosen to elucidate the optimal concentrations of the selected process variables on cholesterol oxidase production. It was found that, cholesterol oxidase production by Streptomyces cavourensis strain NEAE-42 after optimization process was 20.521U/mL which is higher than result obtained from the basal medium before screening process using Plackett-Burman (3.31 U/mL) with a fold of increase 6.19. The cholesterol oxidase level production obtained in this study (20.521U/mL) by the statistical method is higher than many of the reported values.

A Conceptual Model of Natural and Anthropogenic Drivers and Their Influence on the Prince William Sound, Alaska, Ecosystem

PubMed Central

Harwell, Mark A.; Gentile, John H.; Cummins, Kenneth W.; Highsmith, Raymond C.; Hilborn, Ray; McRoy, C. Peter; Parrish, Julia; Weingartner, Thomas

2010-01-01

Prince William Sound (PWS) is a semi-enclosed fjord estuary on the coast of Alaska adjoining the northern Gulf of Alaska (GOA). PWS is highly productive and diverse, with primary productivity strongly coupled to nutrient dynamics driven by variability in the climate and oceanography of the GOA and North Pacific Ocean. The pelagic and nearshore primary productivity supports a complex and diverse trophic structure, including large populations of forage and large fish that support many species of marine birds and mammals. High intra-annual, inter-annual, and interdecadal variability in climatic and oceanographic processes as drives high variability in the biological populations. A risk-based conceptual ecosystem model (CEM) is presented describing the natural processes, anthropogenic drivers, and resultant stressors that affect PWS, including stressors caused by the Great Alaska Earthquake of 1964 and the Exxon Valdez oil spill of 1989. A trophodynamic model incorporating PWS valued ecosystem components is integrated into the CEM. By representing the relative strengths of driver/stressors/effects, the CEM graphically demonstrates the fundamental dynamics of the PWS ecosystem, the natural forces that control the ecological condition of the Sound, and the relative contribution of natural processes and human activities to the health of the ecosystem. The CEM illustrates the dominance of natural processes in shaping the structure and functioning of the GOA and PWS ecosystems. PMID:20862192

A Conceptual Model of Natural and Anthropogenic Drivers and Their Influence on the Prince William Sound, Alaska, Ecosystem.

PubMed

Harwell, Mark A; Gentile, John H; Cummins, Kenneth W; Highsmith, Raymond C; Hilborn, Ray; McRoy, C Peter; Parrish, Julia; Weingartner, Thomas

2010-07-01

Prince William Sound (PWS) is a semi-enclosed fjord estuary on the coast of Alaska adjoining the northern Gulf of Alaska (GOA). PWS is highly productive and diverse, with primary productivity strongly coupled to nutrient dynamics driven by variability in the climate and oceanography of the GOA and North Pacific Ocean. The pelagic and nearshore primary productivity supports a complex and diverse trophic structure, including large populations of forage and large fish that support many species of marine birds and mammals. High intra-annual, inter-annual, and interdecadal variability in climatic and oceanographic processes as drives high variability in the biological populations. A risk-based conceptual ecosystem model (CEM) is presented describing the natural processes, anthropogenic drivers, and resultant stressors that affect PWS, including stressors caused by the Great Alaska Earthquake of 1964 and the Exxon Valdez oil spill of 1989. A trophodynamic model incorporating PWS valued ecosystem components is integrated into the CEM. By representing the relative strengths of driver/stressors/effects, the CEM graphically demonstrates the fundamental dynamics of the PWS ecosystem, the natural forces that control the ecological condition of the Sound, and the relative contribution of natural processes and human activities to the health of the ecosystem. The CEM illustrates the dominance of natural processes in shaping the structure and functioning of the GOA and PWS ecosystems.

Impacts of cattle grazing on spatio-temporal variability of soil moisture and above-ground live plant biomass in mixed grasslands

NASA Astrophysics Data System (ADS)

Virk, Ravinder

Areas with relatively high spatial heterogeneity generally have more biodiversity than spatially homogeneous areas due to increased potential habitat. Management practices such as controlled grazing also affect the biodiversity in grasslands, but the nature of this impact is not well understood. Therefore this thesis studies the impacts of variation in grazing on soil moisture and biomass heterogeneity. These are not only important in terms of management of protected grasslands, but also for designing an effective grazing system from a livestock management point of view. This research is a part of the cattle grazing experiment underway in Grasslands National Park (GNP) of Canada since 2006, as part of the adaptive management process for restoring ecological integrity of the northern mixed-grass prairie region. An experimental approach using field measurements and remote sensing (Landsat) was combined with modelling (CENTURY) to examine and predict the impacts of grazing intensity on the spatial heterogeneity and patterns of above-ground live plant biomass (ALB) in experimental pastures in a mixed grassland ecosystem. The field-based research quantified the temporal patterns and spatial variability in both soil moisture (SM) and ALB, and the influence of local intra-seasonal weather variability and slope location on the spatio-temporal variability of SM and ALB at field plot scales. Significant impacts of intra-seasonal weather variability, slope position and grazing pressure on SM and ALB across a range of scales (plot and local (within pasture)) were found. Grazing intensity significantly affected the ALB even after controlling for the effect of slope position. Satellite-based analysis extended the scale of interest to full pastures and the surrounding region to assess the effects of grazing intensity on the spatio-temporal pattern of ALB in mixed grasslands. Overall, low to moderate grazing intensity showed increase in ALB heterogeneity whereas no change in ALB heterogeneity over time was observed for heavy grazing intensity. All grazing intensities showed decrease in spatial range (patch size) over time indicating that grazing is a patchy process. The study demonstrates that cattle grazing with variable intensity can maintain and change the spatial patterns of vegetation in the studied region. Using a modelling approach, the relative degrees to which grazing intensity and soil properties affect grassland productivity and carbon dynamics at longer time-periods were investigated. Both grass productivity and carbon dynamics are sensitive to variability in soil texture and grazing intensity. Moderate grazing is predicted to be the best option in terms of maintaining sufficient heterogeneity to support species diversity, as well as for carbon management in the mixed grassland ecosystem.

Faces in Context: A Review and Systematization of Contextual Influences on Affective Face Processing

PubMed Central

Wieser, Matthias J.; Brosch, Tobias

2012-01-01

Facial expressions are of eminent importance for social interaction as they convey information about other individuals’ emotions and social intentions. According to the predominant “basic emotion” approach, the perception of emotion in faces is based on the rapid, automatic categorization of prototypical, universal expressions. Consequently, the perception of facial expressions has typically been investigated using isolated, de-contextualized, static pictures of facial expressions that maximize the distinction between categories. However, in everyday life, an individual’s face is not perceived in isolation, but almost always appears within a situational context, which may arise from other people, the physical environment surrounding the face, as well as multichannel information from the sender. Furthermore, situational context may be provided by the perceiver, including already present social information gained from affective learning and implicit processing biases such as race bias. Thus, the perception of facial expressions is presumably always influenced by contextual variables. In this comprehensive review, we aim at (1) systematizing the contextual variables that may influence the perception of facial expressions and (2) summarizing experimental paradigms and findings that have been used to investigate these influences. The studies reviewed here demonstrate that perception and neural processing of facial expressions are substantially modified by contextual information, including verbal, visual, and auditory information presented together with the face as well as knowledge or processing biases already present in the observer. These findings further challenge the assumption of automatic, hardwired categorical emotion extraction mechanisms predicted by basic emotion theories. Taking into account a recent model on face processing, we discuss where and when these different contextual influences may take place, thus outlining potential avenues in future research. PMID:23130011

Real time monitoring of powder blend bulk density for coupled feed-forward/feed-back control of a continuous direct compaction tablet manufacturing process.

PubMed

Singh, Ravendra; Román-Ospino, Andrés D; Romañach, Rodolfo J; Ierapetritou, Marianthi; Ramachandran, Rohit

2015-11-10

The pharmaceutical industry is strictly regulated, where precise and accurate control of the end product quality is necessary to ensure the effectiveness of the drug products. For such control, the process and raw materials variability ideally need to be fed-forward in real time into an automatic control system so that a proactive action can be taken before it can affect the end product quality. Variations in raw material properties (e.g., particle size), feeder hopper level, amount of lubrication, milling and blending action, applied shear in different processing stages can affect the blend density significantly and thereby tablet weight, hardness and dissolution. Therefore, real time monitoring of powder bulk density variability and its incorporation into the automatic control system so that its effect can be mitigated proactively and efficiently is highly desired. However, real time monitoring of powder bulk density is still a challenging task because of different level of complexities. In this work, powder bulk density which has a significant effect on the critical quality attributes (CQA's) has been monitored in real time in a pilot-plant facility, using a NIR sensor. The sensitivity of the powder bulk density on critical process parameters (CPP's) and CQA's has been analyzed and thereby feed-forward controller has been designed. The measured signal can be used for feed-forward control so that the corrective actions on the density variations can be taken before they can influence the product quality. The coupled feed-forward/feed-back control system demonstrates improved control performance and improvements in the final product quality in the presence of process and raw material variations. Copyright © 2015 Elsevier B.V. All rights reserved.

Faces in context: a review and systematization of contextual influences on affective face processing.

PubMed

Wieser, Matthias J; Brosch, Tobias

2012-01-01

Facial expressions are of eminent importance for social interaction as they convey information about other individuals' emotions and social intentions. According to the predominant "basic emotion" approach, the perception of emotion in faces is based on the rapid, automatic categorization of prototypical, universal expressions. Consequently, the perception of facial expressions has typically been investigated using isolated, de-contextualized, static pictures of facial expressions that maximize the distinction between categories. However, in everyday life, an individual's face is not perceived in isolation, but almost always appears within a situational context, which may arise from other people, the physical environment surrounding the face, as well as multichannel information from the sender. Furthermore, situational context may be provided by the perceiver, including already present social information gained from affective learning and implicit processing biases such as race bias. Thus, the perception of facial expressions is presumably always influenced by contextual variables. In this comprehensive review, we aim at (1) systematizing the contextual variables that may influence the perception of facial expressions and (2) summarizing experimental paradigms and findings that have been used to investigate these influences. The studies reviewed here demonstrate that perception and neural processing of facial expressions are substantially modified by contextual information, including verbal, visual, and auditory information presented together with the face as well as knowledge or processing biases already present in the observer. These findings further challenge the assumption of automatic, hardwired categorical emotion extraction mechanisms predicted by basic emotion theories. Taking into account a recent model on face processing, we discuss where and when these different contextual influences may take place, thus outlining potential avenues in future research.

Age-Related Changes in the Processing of Emotional Faces in a Dual-Task Paradigm.

PubMed

Casares-Guillén, Carmen; García-Rodríguez, Beatriz; Delgado, Marisa; Ellgring, Heiner

2016-01-01

Background/ Study Context: Age-related changes appear to affect the ability to identify emotional facial expressions in dual-task conditions (i.e., while simultaneously performing a second visual task). The level of interference generated by the secondary task depends on the phase of emotional processing affected by the interference and the nature of the secondary task. The aim of the present study was to investigate the effect of these variables on age-related changes in the processing of emotional faces. The identification of emotional facial expressions (EFEs) was assessed in a dual-task paradigm using the following variables: (a) the phase during which interference was applied (encoding vs. retrieval phase); and (b) the nature of the interfering stimulus (visuospatial vs. verbal). The sample population consisted of 24 healthy aged adults (mean age = 75.38) and 40 younger adults (mean age = 26.90). The accuracy of EFE identification was calculated for all experimental conditions. Consistent with our hypothesis, the performance of the older group was poorer than that of the younger group in all experimental conditions. Dual-task performance was poorer when the interference occurred during the encoding phase of emotional face processing and when both tasks were of the same nature (i.e., when the experimental condition was more demanding in terms of attention). These results provide empirical evidence of age-related deficits in the identification of emotional facial expressions, which may be partially explained by the impairment of cognitive resources specific to this task. These findings may account for the difficulties experienced by the elderly during social interactions that require the concomitant processing of emotional and environmental information.

Evidence against decay in verbal working memory.

PubMed

Oberauer, Klaus; Lewandowsky, Stephan

2013-05-01

The article tests the assumption that forgetting in working memory for verbal materials is caused by time-based decay, using the complex-span paradigm. Participants encoded 6 letters for serial recall; each letter was preceded and followed by a processing period comprising 4 trials of difficult visual search. Processing duration, during which memory could decay, was manipulated via search set size. This manipulation increased retention interval by up to 100% without having any effect on recall accuracy. This result held with and without articulatory suppression. Two experiments using a dual-task paradigm showed that the visual search process required central attention. Thus, even when memory maintenance by central attention and by articulatory rehearsal was prevented, a large delay had no effect on memory performance, contrary to the decay notion. Most previous experiments that manipulated the retention interval and the opportunity for maintenance processes in complex span have confounded these variables with time pressure during processing periods. Three further experiments identified time pressure as the variable that affected recall. We conclude that time-based decay does not contribute to the capacity limit of verbal working memory. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Beyond interference control impairment in ADHD: evidence from increased intraindividual variability in the color-stroop test.

PubMed

Borella, Erika; de Ribaupierre, Anik; Cornoldi, Cesare; Chicherio, Christian

2013-09-01

The present study investigates intraindividual variability (IIV) in the Color-Stroop test and in a simple reaction time (SRT) task. Performance level and variability in reaction times (RTs)-quantified with different measures such as individual standard deviation (ISD) and coefficient of variation (ICV), as well as ex-Gaussian parameters (mu, sigma, tau)-were analyzed in 24 children with attention deficit/hyperactivity disorder (ADHD) and 24 typically developing children (TDC). Children with ADHD and TDC presented equivalent Color-Stroop interference effects when mean RTs were considered, and the two groups did not differ in the SRT task. Interestingly, compared to TDC, children with ADHD were more variable in their responses, showing increased ISD and ICV in the Color-Stroop interference condition and in the SRT task. Moreover, children with ADHD exhibited higher tau values-that is, more frequent abnormally long RTs-in the Color-Stroop interference condition than did the TDC, but comparable tau values in the SRT, suggesting more variable responses. These results speak in favor of a general deficit in more basic and central processes that only secondarily may affect the efficiency of inhibitory processes in children with ADHD. Overall the present findings confirm the role of IIV as a cornerstone in the ADHD cognitive profile and support the search for fine-grained analysis of performance fluctuations.

Mediating processes between stress and problematic marijuana use.

PubMed

Ketcherside, Ariel; Filbey, Francesca M

2015-06-01

The literature widely reports that stress is associated with marijuana use, yet, to date, the path from stress to marijuana-related problems has not been tested. In this study, we evaluated whether negative affect mediates the relationship between stress and marijuana use. To that end, we tested models to determine mediators between problems with marijuana use (via Marijuana Problem Scale), stress (via Early Life Stress Questionnaire, Perceived Stress Scale), and negative affect (via Beck Depression Inventory; Beck Anxiety Inventory) in 157 current heavy marijuana users. Mediation tests and bootstrap confidence intervals were carried out via the "Mediation" package in R. Depression and anxiety scores both significantly mediated the relationship between perceived stress and problematic marijuana use. Only depression significantly mediated the relationship between early life stress and problematic marijuana use. Early life stress, perceived stress and problematic marijuana use were significant only as independent variables and dependent variables. These findings demonstrate that (1) depression mediated both early life stress and perceived stress, and problematic marijuana use, and, (2) anxiety mediated perceived stress and problematic marijuana use. This mediation analysis represents a strong first step toward understanding the relationship between these variables; however, longitudinal studies are needed to determine causality between these variables. To conclude, addressing concomitant depression and anxiety in those who report either perceived stress or early life stress is important for the prevention of cannabis use disorders. Copyright © 2015. Published by Elsevier Ltd.

Momentum, sensible heat and CO2 correlation coefficient variability: what can we learn from 20 years of continuous eddy covariance measurements?

NASA Astrophysics Data System (ADS)

Hurdebise, Quentin; Heinesch, Bernard; De Ligne, Anne; Vincke, Caroline; Aubinet, Marc

2017-04-01

Long-term data series of carbon dioxide and other gas exchanges between terrestrial ecosystems and atmosphere become more and more numerous. Long-term analyses of such exchanges require a good understanding of measurement conditions during the investigated period. Independently of climate drivers, measurements may indeed be influenced by measurement conditions themselves subjected to long-term variability due to vegetation growth or set-up changes. The present research refers to the Vielsalm Terrestrial Observatory (VTO) an ICOS candidate site located in a mixed forest (beech, silver fir, Douglas fir, Norway spruce) in the Belgian Ardenne. Fluxes of momentum, carbon dioxide and sensible heat have been continuously measured there by eddy covariance for more than 20 years. During this period, changes in canopy height and measurement height occurred. The correlation coefficients (for momemtum, sensible heat and CO2) and the normalized standard deviations measured for the past 20 years at the Vielsalm Terrestrial Observatory (VTO) were analysed in order to define how the fluxes, independently of climate conditions, were affected by the surrounding environment evolution, including tree growth, forest thinning and tower height change. A relationship between canopy aerodynamic distance and the momentum correlation coefficient was found which is characteristic of the roughness sublayer, and suggests that momentum transport processes were affected by z-d. In contrast, no relationship was found for sensible heat and CO2 correlation coefficients, suggesting that the z-d variability observed did not affect their turbulent transport. There were strong differences in these coefficients, however, between two wind sectors, characterized by contrasted stands (height differences, homogeneity) and different hypotheses were raised to explain it. This study highlighted the importance of taking the surrounding environment variability into account in order to ensure the spatio-temporal consistency of datasets.

Spatial variability of sediment transport processes over intra‐ and subtidal timescales within a fringing coral reef system

USGS Publications Warehouse

Pomeroy, Andrew; Lowe, Ryan J.; Ghisalberti, Marco; Winter, Gundula; Storlazzi, Curt D.; Cuttler, Michael V. W.

2018-01-01

Sediment produced on fringing coral reefs that is transported along the bed or in suspension affects ecological reef communities as well as the morphological development of the reef, lagoon, and adjacent shoreline. This study quantified the physical process contribution and relative importance of incident waves, infragravity waves, and mean currents to the spatial and temporal variability of sediment in suspension. Estimates of bed shear stresses demonstrate that incident waves are the key driver of the SSC variability spatially (reef flat, lagoon, and channels) but cannot not fully describe the SSC variability alone. The comparatively small but statistically significant contribution to the bed shear stress by infragravity waves and currents, along with the spatial availability of sediment of a suitable size and volume, is also important. Although intra‐tidal variability in SSC occurs in the different reef zones, the majority of the variability occurs over longer slowly varying (subtidal) time scales, which is related to the arrival of large incident waves at a reef location. The predominant flow pathway, which can transport suspended sediment, consists of cross‐reef flow across the reef flat that diverges in the lagoon and returns offshore through channels. This pathway is primarily due to subtidal variations in wave‐driven flows, but can also be driven alongshore by wind stresses when the incident waves are small. Higher frequency (intra‐tidal) current variability also occur due to both tidal flows, as well as variations in the water depth that influence wave transmission across the reef and wave‐driven currents.

Application of Complex Fluids in Lignocellulose Processing

NASA Astrophysics Data System (ADS)

Carrillo Lugo, Carlos A.

Complex fluids such as emulsions, microemulsions and foams, have been used for different applications due to the multiplicity of properties they possess. In the present work, such fluids are introduced as effective media for processing lignocellulosic biomass. A demonstration of the generic benefits of complex fluids is presented to enhance biomass impregnation, to facilitate pretreatment for fiber deconstruction and to make compatible cellulose fibrils with hydrophobic polymers during composite manufacture. An improved impregnation of woody biomass was accomplished by application of water-continuous microemulsions. Microemulsions with high water content, > 85%, were formulated and wood samples were impregnated by wicking and capillary flooding at atmospheric pressure and temperature. Formulations were designed to effectively impregnate different wood species during shorter times and to a larger extent compared to the single components of the microemulsions (water, oil or surfactant solutions). The viscosity of the microemulsions and their interactions with cell wall constituents in fibers were critical to define the extent of impregnation and solubilization. The relation between composition and formulation variables and the extent of microemulsion penetration in different woody substrates was studied. Formulation variables such as salinity content of the aqueous phase and type of surfactant were elucidated. Likewise, composition variables such as the water-to-oil ratio and surfactant concentration were investigated. These variables affected the characteristics of the microemulsion and determined their effectiveness in wood treatment. Also, the interactions between the surfactant and the substrate had an important contribution in defining microemulsion penetration in the capillary structure of wood. Microemulsions as an alternative pretreatment for the manufacture of cellulose nanofibrils (CNFs) was also studied. Microemulsions were applied to pretreat lignin-free and lignin-containing fibers obtained from various processes. Incorporation of active agents in the microemulsion facilitated fiber pretreatment before deconstruction via grinding and microfluidization. The energy consumed during the manufacture of cellulose nanofibrils was reduced by up to 55 and 32% in the case of lignin-containing and lignin-free fibers. Moreover, such pre-treatment did not affect negatively the mechanical properties of films prepared with the produced CNF. CNF was also used to enhance the stability of normal and multiple emulsions of the water-in-oil-in-water (W/O/W) type and to prevent their creaming. This was achieved by the marked increase in viscosity of the aqueous phase in the presence CNF. Finally, water-continuous emulsions were used to prepare nanocomposite fibers containing polystyrene and CNF. The morphology of composite fibers obtained after electrospinning of emulsions incorporating polystyrene and CNF was affected by parameters such the concentration of surfactant additives present in the microemulsion and the conductivity of the aqueous phase. Overall, emulsions and microemulsions are presented as a convenient platform to improve the compatibility between polymers of different hydrophilicity, to facilitate their processing and integration in composites.

To think or not to think: two pathways towards persuasion by short films on AIDS prevention.

PubMed

Igartua, Juan José; Cheng, Lifen; Lopes, Orquídea

2003-01-01

Health messages are designed to stimulate an active cognitive process in those audiences generally with little involvement. The Elaboration Likelihood Model by Petty and Cacioppo sustains that subjects with high involvement and those with low involvement react differently to the persuasive message to which they are exposed. One efficient way to capture the attention of the low involvement audiences is to insert the messages within an entertainment context. Our study attempted to analyze affective and cognitive processes to explain the impact of these new formats, fictional shorts for HIV/AIDS prevention. A 2 x 2 factorial design was used, with involvement in the AIDS issue (high/low) and the type of format (musical/dialogue) as independent variables. The finding showed the better the quality of the short (with dialogue style) the more negative affectivity was stimulated, also the more cognitive processing was induced, and a more favorable attitude towards preventive behavior was stimulated.

Neuroimaging self-esteem: a fMRI study of individual differences in women

PubMed Central

Lundberg, Erica; Brimson-Théberge, Melanie; Théberge, Jean

2013-01-01

Although neuroimaging studies strongly implicate the medial prefrontal cortex (ventral and dorsal), cingulate gyrus (anterior and posterior), precuneus and temporoparietal cortex in mediating self-referential processing (SRP), little is known about the neural bases mediating individual differences in valenced SRP, that is, processes intrinsic to self-esteem. This study investigated the neural correlates of experimentally engendered valenced SRP via the Visual–Verbal Self-Other Referential Processing Task in 20 women with fMRI. Participants viewed pictures of themselves or unknown other women during separate trials while covertly rehearsing ‘I am’ or ‘She is’, followed by reading valenced trait adjectives, thus variably associating the self/other with positivity/negativity. Response within dorsal and ventral medial prefrontal cortex, cingulate cortex and left temporoparietal cortex varied with individual differences in both pre-task rated self-descriptiveness of the words, as well as task-induced affective responses. Results are discussed as they relate to a social cognitive and affective neuroscience view of self-esteem. PMID:22403154

Financial strain and cognitive-based smoking processes: The explanatory role of depressive symptoms among adult daily smokers.

PubMed

Robles, Zuzuky; Anjum, Sahar; Garey, Lorra; Kauffman, Brooke Y; Rodríguez-Cano, Rubén; Langdon, Kirsten J; Neighbors, Clayton; Reitzel, Lorraine R; Zvolensky, Michael J

2017-07-01

Little work has focused on the underlying mechanisms that may link financial strain and smoking processes. The current study tested the hypothesis that financial strain would exert an indirect effect on cognitive-based smoking processes via depressive symptoms. Three clinically significant dependent variables linked to the maintenance of smoking were evaluated: negative affect reduction motives, negative mood abstinence expectancies, and perceived barriers for quitting. Participants included 102 adult daily smokers (M age =33.0years, SD=13.60; 35.3% female) recruited from the community to participate in a self-guided (unaided; no psychological or pharmacological intervention) smoking cessation study. Results indicated that depressive symptoms explain, in part, the relation between financial strain and smoking motives for negative affect reduction, negative mood abstinence expectancies, and perceived barriers for quitting. Results indicate that smoking interventions for individuals with high levels of financial strain may potentially benefit from the addition of therapeutic tactics aimed at reducing depression. Copyright © 2017 Elsevier Ltd. All rights reserved.

Salinity Effects on the Adsorption of Nucleic Acid Compounds on Na-Montmorillonite: a Prebiotic Chemistry Experiment

NASA Astrophysics Data System (ADS)

Villafañe-Barajas, Saúl A.; Baú, João Paulo T.; Colín-García, María; Negrón-Mendoza, Alicia; Heredia-Barbero, Alejandro; Pi-Puig, Teresa; Zaia, Dimas A. M.

2018-02-01

Any proposed model of Earth's primitive environments requires a combination of geochemical variables. Many experiments are prepared in aqueous solutions and in the presence of minerals. However, most sorption experiments are performed in distilled water, and just a few in seawater analogues, mostly inconsistent with a representative primitive ocean model. Therefore, it is necessary to perform experiments that consider the composition and concentration of dissolved salts in the early ocean to understand how these variables could have affected the absorption of organic molecules into minerals. In this work, the adsorption of adenine, adenosine, and 5'AMP onto Na+montmorillonite was studied using a primitive ocean analog (4.0 Ga) from experimental and computational approaches. The order of sorption of the molecules was: 5'AMP > adenine > adenosine. Infrared spectra showed that the interaction between these molecules and montmorillonite occurs through the NH2 group. In addition, electrostatic interaction between negatively charged montmorillonite and positively charge N1 of these molecules could occur. Results indicate that dissolved salts affect the sorption in all cases; the size and structure of each organic molecule influence the amount sorbed. Specifically, the X-ray diffraction patterns show that dissolved salts occupy the interlayer space in Na-montmorillonite and compete with organic molecules for available sites. The adsorption capacity is clearly affected by dissolved salts in thermodynamic terms as deduced by isotherm models. Indeed, molecular dynamic models suggest that salts are absorbed in the interlamellar space and can interact with oxygen atoms exposed in the edges of clay or in its surface, reducing the sorption of the organic molecules. This research shows that the sorption process could be affected by high concentration of salts, since ions and organic molecules may compete for available sites on inorganic surfaces. Salt concentration in primitive oceans may have strongly affected the sorption, and hence the concentration processes of organic molecules on minerals.

Land Cover Land Use Change and Soil Organic Carbon under Climate Variability in the Semi-Arid West African Sahel (1960-2050)

ERIC Educational Resources Information Center

Dieye, Amadou M.

2016-01-01

Land Cover Land Use (LCLU) change affects land surface processes recognized to influence climate change at local, national and global levels. Soil organic carbon is a key component for the functioning of agro-ecosystems and has a direct effect on the physical, chemical and biological characteristics of the soil. The capacity to model and project…

Processes Affecting the Variability of Fluorescence Signals from Benthic Targets in Shallow Waters

DTIC Science & Technology

1998-09-30

analysis of zooxanthellae isolated from coral samples. We examined fluorescence lifetimes from benthic targets using femtosecond laser based Single...a temporal resolution 5 ps. The laser set-up was employed for laboratory studies of fluorescence lifetimes from model targets such as zooxanthellae ...seagrasses. Over 200 measurements on isolated zooxanthellae were conducted with a bench-top FRR fluorometer and Phase Shift Fluorometer. During the CoBOP-98

Binary black holes' effects on electromagnetic fields.

PubMed

Palenzuela, Carlos; Anderson, Matthew; Lehner, Luis; Liebling, Steven L; Neilsen, David

2009-08-21

In addition to producing gravitational waves, the dynamics of a binary black hole system could induce emission of electromagnetic radiation by affecting the behavior of plasmas and electromagnetic fields in their vicinity. We here study how the electromagnetic fields are affected by a pair of orbiting black holes through the merger. In particular, we show how the binary's dynamics induce a variability in possible electromagnetically induced emissions as well as a possible enhancement of electromagnetic fields during the late-merge and merger epochs. These time dependent features will likely leave their imprint in processes generating detectable emissions and can be exploited in the detection of electromagnetic counterparts of gravitational waves.

Antifungal Therapy in Birds: Old Drugs in a New Jacket.

PubMed

Antonissen, Gunther; Martel, An

2018-05-01

The use of antifungals in birds is characterized by interspecies and interindividual variability in the pharmacokinetics, affecting drug safety and efficacy. Oral antifungal drug absorption is a complex process affected by drug formulation characteristics, gastrointestinal anatomy, and physiology. New antifungal drug delivery systems can enhance drug stability, reduce off-target side effects, prolong residence time in the blood, and improve efficacy. Topical administration of antifungals through nebulization shows promising results. However, therapeutic output is highly influenced by drug formulation and type of nebulizer, indicating these factors should be taken into account when selecting this medication route. Copyright © 2018 Elsevier Inc. All rights reserved.

Effects of formulation variables and characterization of guaifenesin wax microspheres for controlled release.

PubMed

Mani, Narasimhan; Park, M O; Jun, H W

2005-01-01

Sustained-release wax microspheres of guaifenesin, a highly water-soluble drug, were prepared by the hydrophobic congealable disperse method using a salting-out procedure. The effects of formulation variables on the loading efficiency, particle properties, and in-vitro drug release from the microspheres were determined. The type of dispersant, the amount of wetting agent, and initial stirring time used affected the loading efficiency, while the volume of external phase and emulsification speed affected the particle size of the microspheres to a greater extent. The crystal properties of the drug in the wax matrix and the morphology of the microspheres were studied by differential scanning calorimetry (DSC), powder x-ray diffraction (XRD), and scanning electron microscopy (SEM). The DSC thermograms of the microspheres showed that the drug lost its crystallinity during the microencapsulation process, which was further confirmed by the XRD data. The electron micrographs of the drug-loaded microspheres showed well-formed spherical particles with a rough exterior.

Variables affecting the propensity to buy branded beef among groups of Australian beef buyers.

PubMed

Morales, L Emilio; Griffith, Garry; Wright, Victor; Fleming, Euan; Umberger, Wendy; Hoang, Nam

2013-06-01

Australian beef consumers have different preferences given their characteristics and the effect on expected quality of cues related to health, production process and eating experience. Beef brands using Meat Standards Australia (MSA) grades can help to signal quality and reduce consumers' uncertainty when shopping. The objective of this study is to identify the characteristics of beef buyers and their perceptions about product attributes that affect the propensity to buy branded beef. Binary logistic models were applied identifying differences between all respondents and the potential target market, including buyers in medium to high income segments, and between buyers in the target market who would buy branded beef for taste and health reasons. Variables increasing the propensity to buy branded beef include previous experience, appreciation for branded cuts and concern about quality more than size. Finally, variations in preferences for marbling and cut were found between buyers who would buy branded beef for taste and health reasons. Copyright © 2013 Elsevier Ltd. All rights reserved.

Variability in pesticides residues--the US experience.

PubMed

Suhre, F B

2000-07-01

The evolution of US Environmental Protection Agency's (EPA) process for estimating potential health risks from pesticide residues in or on food is examined in light of changes in US Legislation and the variability of residue data and assumptions used to estimate dietary exposure. In the 86 years since enactment of the Insecticide Act, pesticide laws have become progressively more health-based. Passage of the 1996 Food Quality Protection Act (FQPA) requires EPA to place particular emphasis on assessing potential risk from pesticides to infants and children. Primary factors affecting the actual pesticide residues in food include frequency of application, percentage of crop treated, and the interval from treatment to harvest. Primary factors affecting the estimated pesticide residues in food include the source of the residue data, calculation techniques for non-detected residues, and the availability of data reflecting post-harvest treatments. Risk assessors must thoroughly consider these factors when assessing dietary risk to pesticides. Risk managers will need to consider these factors as a means of mitigating dietary risk from pesticides.

On the evaluation of cultural and environmental public goods, and its implications for social innovation.

PubMed

Graffeo, Michele; Bonini, Nicolao

2013-01-01

Public goods (e.g., parks) and welfare services (e.g., garbage disposal and transportation policies) are extremely important for the citizens' well-being but in the complex modern societies their influence and effectiveness are affected by the citizens' support. For this reason, it is crucial to understand which are the factors that influence the citizens' perception of the benefits, costs, and risks associated to public goods and welfare services. In this chapter, we describe some psychological variables that are relevant for the evaluation process of the public goods, but that are not considered by the standard economic models. At the same time, we show that some variables of central importance for the economic models do not significantly affect the citizens' evaluations. Finally, we discuss the concept of Nudge, a policy-making approach that suggests the use of psychological mechanisms to increase the citizens' support to public provision of welfare services. Copyright © 2013 Elsevier B.V. All rights reserved.

The Impact of an Ego Depletion Manipulation on Performance-Based and Self-Report Assessment Measures.

PubMed

Charek, Daniel B; Meyer, Gregory J; Mihura, Joni L

2016-10-01

We investigated the impact of ego depletion on selected Rorschach cognitive processing variables and self-reported affect states. Research indicates acts of effortful self-regulation transiently deplete a finite pool of cognitive resources, impairing performance on subsequent tasks requiring self-regulation. We predicted that relative to controls, ego-depleted participants' Rorschach protocols would have more spontaneous reactivity to color, less cognitive sophistication, and more frequent logical lapses in visualization, whereas self-reports would reflect greater fatigue and less attentiveness. The hypotheses were partially supported; despite a surprising absence of self-reported differences, ego-depleted participants had Rorschach protocols with lower scores on two variables indicative of sophisticated combinatory thinking, as well as higher levels of color receptivity; they also had lower scores on a composite variable computed across all hypothesized markers of complexity. In addition, self-reported achievement striving moderated the effect of the experimental manipulation on color receptivity, and in the Depletion condition it was associated with greater attentiveness to the tasks, more color reactivity, and less global synthetic processing. Results are discussed with an emphasis on the response process, methodological limitations and strengths, implications for calculating refined Rorschach scores, and the value of using multiple methods in research and experimental paradigms to validate assessment measures. © The Author(s) 2015.

Processing Pipeline of Sugarcane Spectral Response to Characterize the Fallen Plants Phenomenon

NASA Astrophysics Data System (ADS)

Solano, Agustín; Kemerer, Alejandra; Hadad, Alejandro

2016-04-01

Nowadays, in agronomic systems it is possible to make a variable management of inputs to improve the efficiency of agronomic industry and optimize the logistics of the harvesting process. In this way, it was proposed for sugarcane culture the use of remote sensing tools and computational methods to identify useful areas in the cultivated lands. The objective was to use these areas to make variable management of the crop. When at the moment of harvesting the sugarcane there are fallen stalks, together with them some strange material (vegetal or mineral) is collected. This strange material is not millable and when it enters onto the sugar mill it causes important looses of efficiency in the sugar extraction processes and affects its quality. Considering this issue, the spectral response of sugarcane plants in aerial multispectral images was studied. The spectral response was analyzed in different bands of the electromagnetic spectrum. Then, the aerial images were segmented to obtain homogeneous regions useful for producers to make decisions related to the use of inputs and resources according to the variability of the system (existence of fallen cane and standing cane). The obtained segmentation results were satisfactory. It was possible to identify regions with fallen cane and regions with standing cane with high precision rates.

Time Resolved Spectroscopy of Cepheid Variable Stars

NASA Astrophysics Data System (ADS)

Hartman, Katherine; Beaton, Rachael L.; SDSS-IV APOGEE-2 Team

2018-01-01

Galactic Cepheid variable stars have been used for over a century as standard candles and as the first rung of the cosmic distance ladder, integral to the calculation of the Hubble constant. However, it is challenging to observe Cepheids within the Milky Way Galaxy because of extinction, and there are still uncertainties in the Cepheid period-luminosity relation (or Leavitt Law) that affect these important distance calculations. The Apache Point Observatory Galactic Evolution Experiment (APOGEE) survey has provided spectra for a large sample of Galactic Cepheids, but the standard chemical abundance pipeline (ASPCAP) processing is not well-suited to pulsational variables, preventing us from using them to study metallicity effect in the Leavitt Law with standard processing. Using a standalone version of the ASPCAP pipeline, we present an analysis of individual visit spectra from a test sample of nine APOGEE Cepheids, and we compare its output to the stars’ literature abundance values. Based on the results of this comparison, we will be able to improve the standard analysis and process the entirety of APOGEE’s Cepheid catalogue to improve its abundance measurements. The resulting abundance data will allow us to constrain the effect of metallicity on the Leavitt Law and thus allow for more accurate Cepheid distance measurements for the determination of the Hubble constant.

Multi-criteria analysis for PM10 planning

NASA Astrophysics Data System (ADS)

Pisoni, Enrico; Carnevale, Claudio; Volta, Marialuisa

To implement sound air quality policies, Regulatory Agencies require tools to evaluate outcomes and costs associated to different emission reduction strategies. These tools are even more useful when considering atmospheric PM10 concentrations due to the complex nonlinear processes that affect production and accumulation of the secondary fraction of this pollutant. The approaches presented in the literature (Integrated Assessment Modeling) are mainly cost-benefit and cost-effective analysis. In this work, the formulation of a multi-objective problem to control particulate matter is proposed. The methodology defines: (a) the control objectives (the air quality indicator and the emission reduction cost functions); (b) the decision variables (precursor emission reductions); (c) the problem constraints (maximum feasible technology reductions). The cause-effect relations between air quality indicators and decision variables are identified tuning nonlinear source-receptor models. The multi-objective problem solution provides to the decision maker a set of not-dominated scenarios representing the efficient trade-off between the air quality benefit and the internal costs (emission reduction technology costs). The methodology has been implemented for Northern Italy, often affected by high long-term exposure to PM10. The source-receptor models used in the multi-objective analysis are identified processing long-term simulations of GAMES multiphase modeling system, performed in the framework of CAFE-Citydelta project.

Using interviews and peer pairs to better understand how school environments affect young children's playground physical activity levels: a qualitative study.

PubMed

Parrish, Anne-Maree; Yeatman, Heather; Iverson, Don; Russell, Ken

2012-04-01

School break times provide a daily opportunity for children to be active; however, research indicates this time is underutilized. Reasons for low children's playground activity levels have primarily focused on physical barriers. This research aimed to contribute to physical environmental findings affecting children's playground physical activity levels by identifying additional variables through the interview process. Thirteen public schools were included in the sample (total 2946 children). Physical activity and environmental data were collected over 3 days. Environmental variables were manually assessed at each of the 13 schools. Observational data were used to determine which three schools were the most and least active. The principal, three teachers and 20 students in Grades 4-6 from these six schools (four lower and two average socioeconomic status) were invited to participate in the interview process. Student interviews involved the paired interview technique. The main themes generated from the school interviews included the effect of non-fixed equipment (including balls), playground markings, playground aesthetics, activity preference, clothing, the amount of break time available for play, teacher playground involvement, gender, bullying, school policies, student confidence in break-time activity and fundamental movement skills. The effect of bullying on playground physical activity levels was concerning.

A case for using Plethodontid salamanders for monitoring biodiversity and ecosystem integrity of North American forests

USGS Publications Warehouse

Welsh, H.H.; Droege, S.

2001-01-01

Terrestrial salamanders of the family P!ethodontidae have unique attributes that make them excellent indicators of biodiversity and ecosystem integrity in forested habitats. Their longevity, small territory size, site fidelity, sensitivity to natural and anthropogenic perturbations, tendency to occur in high densities, and low sampling costs mean that counts of plethodontid salamanders provide numerous advantages over counts of other North American forest organisms for indicating environmental change. Furthermore, they are tightly linked physiologically to microclimatic and successional processes that influence the distribution and abundance of numerous other hydrophilic but difficult-to-study forest-dwelling plants and animals. Ecosystem processes such as moisture cycling, food-web dynamics, and succession, with their related structural and microclimatic variability, all affect forest biodiversity and have been shown to affect salamander populations as well. We determined the variability associated with sampling for plethodontid salamanders by estimating the coefficient of variation (CV) from available time-series data. The median coefficient of variation indicated that variation in counts of individuals among studies was much lower in plethodonticis (27%) than in lepidoptera (93%), passerine birds (57%), small mammals (69%), or other amphibians (37-46%), which means plethodontid salamanders provide an important statistical advantage over other species for monitoring long-term forest health.

Direct and Indirect Effects of Maternal and Peer Influences on Sexual Intention among Urban African American and Hispanic Females

PubMed Central

Barman-Adhikari, Anamika; Cederbaum, Julie; Sathoff, Chelsea; Toro, Rosa

2014-01-01

Peer and family influences are interconnected in complex ways. These influences shape adolescent decision-making regarding engagement in sexual behaviors. Evidence indicates the more proximal (and direct) a process is to an individual, the more likely it is to affect his/her development and behavior. Therefore, family factors (e.g., parenting practices) and peer influence (e.g., peer norms) tend to be more strongly associated with adolescent behavior than distal factors (e.g., media or the economy). Guided by an ecological framework, this study explored how maternal influence variables interact with perceptions of peer influence to affect daughters' intentions to have sex. A nonprobability sample of 176 mother-daughter dyads was recruited in clinics and service organizations in the northeastern United States. Results from path analysis revealed that maternal influence variables had a significant indirect relationship with daughters' intentions to have sex through daughters' perceptions of peer influence. Maternal processes can act as protective factors for adolescent girls who perceive their peers are engaged in sexual behaviors. Therefore, risk reduction interventions with adolescents should include opportunities for parents to learn about sex-related issues and develop skills that will allow them to buffer negative peer influence. PMID:25422533

Biogeochemical evolution of a landfill leachate plume, Norman, Oklahoma

USGS Publications Warehouse

Cozzarelli, Isabelle M.; Böhlke, John Karl; Masoner, Jason R.; Breit, George N.; Lorah, Michelle M.; Tuttle, Michele L.W.; Jaeschke, Jeanne B.

2011-01-01

Leachate from municipal landfills can create groundwater contaminant plumes that may last for decades to centuries. The fate of reactive contaminants in leachate-affected aquifers depends on the sustainability of biogeochemical processes affecting contaminant transport. Temporal variations in the configuration of redox zones downgradient from the Norman Landfill were studied for more than a decade. The leachate plume contained elevated concentrations of nonvolatile dissolved organic carbon (NVDOC) (up to 300 mg/L), methane (16 mg/L), ammonium (650 mg/L as N), iron (23 mg/L), chloride (1030 mg/L), and bicarbonate (4270 mg/L). Chemical and isotopic investigations along a 2D plume transect revealed consumption of solid and aqueous electron acceptors in the aquifer, depleting the natural attenuation capacity. Despite the relative recalcitrance of NVDOC to biodegradation, the center of the plume was depleted in sulfate, which reduces the long-term oxidation capacity of the leachate-affected aquifer. Ammonium and methane were attenuated in the aquifer relative to chloride by different processes: ammonium transport was retarded mainly by physical interaction with aquifer solids, whereas the methane plume was truncated largely by oxidation. Studies near plume boundaries revealed temporal variability in constituent concentrations related in part to hydrologic changes at various time scales. The upper boundary of the plume was a particularly active location where redox reactions responded to recharge events and seasonal water-table fluctuations. Accurately describing the biogeochemical processes that affect the transport of contaminants in this landfill-leachate-affected aquifer required understanding the aquifer's geologic and hydrodynamic framework.

Rumination, experiential avoidance, and dysfunctional thinking in eating disorders

PubMed Central

Rawal, Adhip; Park, Rebecca J.; Williams, J. Mark G.

2010-01-01

The majority of research in eating disorders (ED) has investigated the content of disorder-specific thoughts, while few studies have addressed underlying cognitive-affective processes. A better understanding of processes underpinning ED may have important implications for treatment development. Two studies were conducted that investigated levels of rumination, beliefs about rumination, experiential avoidance, and aspects of schematic thinking in individuals with eating pathology. The latter was assessed with a newly designed ED-Sentence Completion Task (ED-SCT). Study 1 (N = 177) examined relations between ED psychopathology and these variables in a student population. Extending this, Study 2 (N = 26) assessed differences between patients with anorexia nervosa and healthy control participants. The results showed that ED psychopathology was related to disorder-specific cognitions, experiential avoidance as well as ruminative brooding but not reflection. A follow-up of anorexia nervosa patients indicated that changes in ED psychopathology were associated with changes in dysfunctional attitudes and maladaptive cognitive-affective processes. These findings highlight cognitive processes that may play an important role in the maintenance of eating pathology. PMID:20598670

Preparation of Effective Operating Manuals to Support Waste Management Plant Operator Training

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

Brown, S. R.

2003-02-25

Effective plant operating manuals used in a formal training program can make the difference between a successful operation and a failure. Once the plant process design and control strategies have been fixed, equipment has been ordered, and the plant is constructed, the only major variable affecting success is the capability of plant operating personnel. It is essential that the myriad details concerning plant operation are documented in comprehensive operating manuals suitable for training the non-technical personnel that will operate the plant. These manuals must cover the fundamental principles of each unit operation including how each operates, what process variables aremore » important, and the impact of each variable on the overall process. In addition, operators must know the process control strategies, process interlocks, how to respond to alarms, each of the detailed procedures required to start up and optimize the plant, and every control loop-including when it is appropriate to take manual control. More than anything else, operating mistakes during the start-up phase can lead to substantial delays in achieving design processing rates as well as to problems with government authorities if environmental permit limits are exceeded. The only way to assure return on plant investment is to ensure plant operators have the knowledge to properly run the plant from the outset. A comprehensive set of operating manuals specifically targeted toward plant operators and supervisors written by experienced operating personnel is the only effective way to provide the necessary information for formal start-up training.« less

Denudational surface processes and trends of relief development in mountain valleys in western Norway

NASA Astrophysics Data System (ADS)

Laute, Katja; Beylich, Achim A.

2014-05-01

The various rates at which mountain landscapes are changing today are a response to (i) the long-term landscape history, (ii) the contemporary imprint of current tectonic activity, (iii) climate variability and (iv) anthropogenic influences. Large areas of the Norwegian mountainous fjord landscapes are today occupied by hillslopes which reflect the influence of glacial inheritance from the Last Glacial Maximum (LGM) as a direct response to climate variability during the Pleistocene. This study deals with the quantitative analysis of denudational slope processes and relief development occurring in selected mountain valleys in western Norway from the end of the LGM until today. The main focus of this research is two-fold: (i) analyzing the complexity of hillslope development since the LGM in glacially formed valleys, and (ii) assessing the spatio-temporal variability, controls and rates of relevant denudational slope processes operating under Holocene to contemporary environmental conditions in western Norway. Five years of research (2009-2013) were conducted in two steep, parabolic-shaped and glacier-connected neighbouring drainage basins, Erdalen (79.5 km2) and Bødalen (60.1 km2), located on the western side of the Jostedalsbreen ice cap in western Norway. The process-based approach applied encompasses techniques and methods for geomorphic process analysis of past (e.g. DEM/GIS based spatial data analysis, geophysical investigation of slope storage) and contemporary (process monitoring in field, in-depth studies of relevant slope processes) denudational process activity. The main results of this work reveal that the Holocene to contemporary slope processes and the connected relief development during this time period are primarily controlled by the imprint of the glacial history of the study areas which can be seen as a direct response to climate variability. Apart from that, a significant influence of the Little Ice Age (LIA) glacier advance on hillslope morphometry was discovered, with the LIA glacier advance causing higher intensities of post-LIA denudation on hillslope systems affected by the LIA glacier advance as compared to non-affected hillslope systems. Distinct differences are found between single headwater systems of the Erdalen and Bødalen drainage basins (i) regarding the absolute and relative importance of different contemporary slope processes as well as (ii) with respect to the importance of sediment delivery from headwater systems for the sedimentary budgets of the entire drainage basin systems. The detected differences are seen as a direct consequence of the varying glacially inherited valley morphometries which determine hillslope storage capacity, the average process transport distances and the intensity of hillslope-channel coupling. A comparison to geomorphic process rates published for other cold climate environments situated at high latitudes of the northern hemisphere permits the statement that the general intensity of present-day denudational processes in Erdalen and Bødalen is in a comparable range of magnitude. Even though denudational slope processes are leading to an ongoing valley widening, the Holocene modification of the inherited glacial relief until today is regarded to be minor. The results from the two selected typical drainage basins are considered to be representative on a regional scale for the mountainous fjord landscape in western Norway.

Calibration of visually guided reaching is driven by error-corrective learning and internal dynamics.

PubMed

Cheng, Sen; Sabes, Philip N

2007-04-01

The sensorimotor calibration of visually guided reaching changes on a trial-to-trial basis in response to random shifts in the visual feedback of the hand. We show that a simple linear dynamical system is sufficient to model the dynamics of this adaptive process. In this model, an internal variable represents the current state of sensorimotor calibration. Changes in this state are driven by error feedback signals, which consist of the visually perceived reach error, the artificial shift in visual feedback, or both. Subjects correct for > or =20% of the error observed on each movement, despite being unaware of the visual shift. The state of adaptation is also driven by internal dynamics, consisting of a decay back to a baseline state and a "state noise" process. State noise includes any source of variability that directly affects the state of adaptation, such as variability in sensory feedback processing, the computations that drive learning, or the maintenance of the state. This noise is accumulated in the state across trials, creating temporal correlations in the sequence of reach errors. These correlations allow us to distinguish state noise from sensorimotor performance noise, which arises independently on each trial from random fluctuations in the sensorimotor pathway. We show that these two noise sources contribute comparably to the overall magnitude of movement variability. Finally, the dynamics of adaptation measured with random feedback shifts generalizes to the case of constant feedback shifts, allowing for a direct comparison of our results with more traditional blocked-exposure experiments.

Optimization of conditions for isolation of high quality chitin from shrimp processing raw byproducts using response surface methodology and its characterization.

PubMed

Nidheesh, T; Suresh, P V

2015-06-01

Chitin is one of the most abundant bioactive biopolymer on earth. It is commercially extracted from seafood processing crustacean shell byproducts by harsh thermochemical treatments. The extraction conditions, the source and pretreatment of raw material significantly affect its quality and bioactivity. In this investigation response surface methodology (RSM) has been applied to optimize and evaluate the interaction of variables for extraction of high quality chitin from shrimp processing raw byproducts. Variables such as, concentration of HCl (%, v/v) 4.5 (for wet) and 4.9 (for dry), reaction time 3 h, solid liquid ratio of HCl (w/v) 1:5.5 (for wet) and 1:7.9 (for dry) with two treatments achieved >98 % demineralization of shrimp byproduct. Variables such as, concentration of NaOH 3.6 % (w/v), reaction time 2.5 h, temperature 69.0 ± 1 °C, solid liquid ratio of NaOH 7.4 (w/v) and two treatments accomplished >98 % deproteinization of demineralized byproducts. Significant (p ≤ 0.05-0.001) interactive effects were observed between different variables. Chitin obtained in these conditions had residual content (%, w/w) of ash <0.4 and protein <0.8 and the degree of N-acetylation was >93 % with purity of >98 %. In conclusion, the optimized conditions by RSM can be applied for large scale preparation of high quality chitin from raw shrimp byproduct.

Assessing spatial and temporal variability of acid-extractable organics in oil sands process-affected waters.

PubMed

Frank, Richard A; Milestone, Craig B; Rowland, Steve J; Headley, John V; Kavanagh, Richard J; Lengger, Sabine K; Scarlett, Alan G; West, Charles E; Peru, Kerry M; Hewitt, L Mark

2016-10-01

The acid-extractable organic compounds (AEOs), including naphthenic acids (NAs), present within oil sands process-affected water (OSPW) receive great attention due to their known toxicity. While recent progress in advanced separation and analytical methodologies for AEOs has improved our understanding of the composition of these mixtures, little is known regarding any variability (i.e., spatial, temporal) inherent within, or between, tailings ponds. In this study, 5 samples were collected from the same location of one tailings pond over a 2-week period. In addition, 5 samples were collected simultaneously from different locations within a tailings pond from a different mine site, as well as its associated recycling pond. In both cases, the AEOs were analyzed using SFS, ESI-MS, HRMS, GC×GC-ToF/MS, and GC- & LC-QToF/MS (GC analyses following conversion to methyl esters). Principal component analysis of HRMS data was able to distinguish the ponds from each other, while data from GC×GC-ToF/MS, and LC- and GC-QToF/MS were used to differentiate samples from within the temporal and spatial sample sets, with the greater variability associated with the latter. Spatial differences could be attributed to pond dynamics, including differences in inputs of tailings and surface run-off. Application of novel chemometric data analyses of unknown compounds detected by LC- and GC-QToF/MS allowed further differentiation of samples both within and between data sets, providing an innovative approach for future fingerprinting studies. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

The Relationship Between Intensity Coding and Binaural Sensitivity in Adults With Cochlear Implants.

PubMed

Todd, Ann E; Goupell, Matthew J; Litovsky, Ruth Y

Many bilateral cochlear implant users show sensitivity to binaural information when stimulation is provided using a pair of synchronized electrodes. However, there is large variability in binaural sensitivity between and within participants across stimulation sites in the cochlea. It was hypothesized that within-participant variability in binaural sensitivity is in part affected by limitations and characteristics of the auditory periphery which may be reflected by monaural hearing performance. The objective of this study was to examine the relationship between monaural and binaural hearing performance within participants with bilateral cochlear implants. Binaural measures included dichotic signal detection and interaural time difference discrimination thresholds. Diotic signal detection thresholds were also measured. Monaural measures included dynamic range and amplitude modulation detection. In addition, loudness growth was compared between ears. Measures were made at three stimulation sites per listener. Greater binaural sensitivity was found with larger dynamic ranges. Poorer interaural time difference discrimination was found with larger difference between comfortable levels of the two ears. In addition, poorer diotic signal detection thresholds were found with larger differences between the dynamic ranges of the two ears. No relationship was found between amplitude modulation detection thresholds or symmetry of loudness growth and the binaural measures. The results suggest that some of the variability in binaural hearing performance within listeners across stimulation sites can be explained by factors nonspecific to binaural processing. The results are consistent with the idea that dynamic range and comfortable levels relate to peripheral neural survival and the width of the excitation pattern which could affect the fidelity with which central binaural nuclei process bilateral inputs.

Compensation for Lithography Induced Process Variations during Physical Design

NASA Astrophysics Data System (ADS)

Chin, Eric Yiow-Bing

This dissertation addresses the challenge of designing robust integrated circuits in the deep sub micron regime in the presence of lithography process variability. By extending and combining existing process and circuit analysis techniques, flexible software frameworks are developed to provide detailed studies of circuit performance in the presence of lithography variations such as focus and exposure. Applications of these software frameworks to select circuits demonstrate the electrical impact of these variations and provide insight into variability aware compact models that capture the process dependent circuit behavior. These variability aware timing models abstract lithography variability from the process level to the circuit level and are used to estimate path level circuit performance with high accuracy with very little overhead in runtime. The Interconnect Variability Characterization (IVC) framework maps lithography induced geometrical variations at the interconnect level to electrical delay variations. This framework is applied to one dimensional repeater circuits patterned with both 90nm single patterning and 32nm double patterning technologies, under the presence of focus, exposure, and overlay variability. Studies indicate that single and double patterning layouts generally exhibit small variations in delay (between 1--3%) due to self compensating RC effects associated with dense layouts and overlay errors for layouts without self-compensating RC effects. The delay response of each double patterned interconnect structure is fit with a second order polynomial model with focus, exposure, and misalignment parameters with 12 coefficients and residuals of less than 0.1ps. The IVC framework is also applied to a repeater circuit with cascaded interconnect structures to emulate more complex layout scenarios, and it is observed that the variations on each segment average out to reduce the overall delay variation. The Standard Cell Variability Characterization (SCVC) framework advances existing layout-level lithography aware circuit analysis by extending it to cell-level applications utilizing a physically accurate approach that integrates process simulation, compact transistor models, and circuit simulation to characterize electrical cell behavior. This framework is applied to combinational and sequential cells in the Nangate 45nm Open Cell Library, and the timing response of these cells to lithography focus and exposure variations demonstrate Bossung like behavior. This behavior permits the process parameter dependent response to be captured in a nine term variability aware compact model based on Bossung fitting equations. For a two input NAND gate, the variability aware compact model captures the simulated response to an accuracy of 0.3%. The SCVC framework is also applied to investigate advanced process effects including misalignment and layout proximity. The abstraction of process variability from the layout level to the cell level opens up an entire new realm of circuit analysis and optimization and provides a foundation for path level variability analysis without the computationally expensive costs associated with joint process and circuit simulation. The SCVC framework is used with slight modification to illustrate the speedup and accuracy tradeoffs of using compact models. With variability aware compact models, the process dependent performance of a three stage logic circuit can be estimated to an accuracy of 0.7% with a speedup of over 50,000. Path level variability analysis also provides an accurate estimate (within 1%) of ring oscillator period in well under a second. Another significant advantage of variability aware compact models is that they can be easily incorporated into existing design methodologies for design optimization. This is demonstrated by applying cell swapping on a logic circuit to reduce the overall delay variability along a circuit path. By including these variability aware compact models in cell characterization libraries, design metrics such as circuit timing, power, area, and delay variability can be quickly assessed to optimize for the correct balance of all design metrics, including delay variability. Deterministic lithography variations can be easily captured using the variability aware compact models described in this dissertation. However, another prominent source of variability is random dopant fluctuations, which affect transistor threshold voltage and in turn circuit performance. The SCVC framework is utilized to investigate the interactions between deterministic lithography variations and random dopant fluctuations. Monte Carlo studies show that the output delay distribution in the presence of random dopant fluctuations is dependent on lithography focus and exposure conditions, with a 3.6 ps change in standard deviation across the focus exposure process window. This indicates that the electrical impact of random variations is dependent on systematic lithography variations, and this dependency should be included for precise analysis.

A review of dark fermentative hydrogen production from biodegradable municipal waste fractions.

PubMed

De Gioannis, G; Muntoni, A; Polettini, A; Pomi, R

2013-06-01

Hydrogen is believed to play a potentially key role in the implementation of sustainable energy production, particularly when it is produced from renewable sources and low energy-demanding processes. In the present paper an attempt was made at critically reviewing more than 80 recent publications, in order to harmonize and compare the available results from different studies on hydrogen production from FW and OFMSW through dark fermentation, and derive reliable information about process yield and stability in view of building related predictive models. The review was focused on the effect of factors, recognized as potentially affecting process evolution (including type of substrate and co-substrate and relative ratio, type of inoculum, food/microorganisms [F/M] ratio, applied pre-treatment, reactor configuration, temperature and pH), on the fermentation yield and kinetics. Statistical analysis of literature data from batch experiments was also conducted, showing that the variables affecting the H2 production yield were ranked in the order: type of co-substrate, type of pre-treatment, operating pH, control of initial pH and fermentation temperature. However, due to the dispersion of data observed in some instances, the ambiguity about the presence of additional hidden variables cannot be resolved. The results from the analysis thus suggest that, for reliable predictive models of fermentative hydrogen production to be derived, a high level of consistency between data is strictly required, claiming for more systematic and comprehensive studies on the subject. Copyright © 2013 Elsevier Ltd. All rights reserved.

Neuropsychological and FDG-PET profiles in VGKC autoimmune limbic encephalitis.

PubMed

Dodich, Alessandra; Cerami, Chiara; Iannaccone, Sandro; Marcone, Alessandra; Alongi, Pierpaolo; Crespi, Chiara; Canessa, Nicola; Andreetta, Francesca; Falini, Andrea; Cappa, Stefano F; Perani, Daniela

2016-10-01

Limbic encephalitis (LE) is characterized by an acute or subacute onset with memory impairments, confusional state, behavioral disorders, variably associated with seizures and dystonic movements. It is due to inflammatory processes that selectively affect the medial temporal lobe structures. Voltage-gate potassium channel (VGKC) autoantibodies are frequently observed. In this study, we assessed at the individual level FDG-PET brain metabolic dysfunctions and neuropsychological profiles in three autoimmune LE cases seropositive for neuronal VGKC-complex autoantibodies. LGI1 and CASPR2 potassium channel complex autoantibody subtyping was performed. Cognitive abilities were evaluated with an in-depth neuropsychological battery focused on episodic memory and affective recognition/processing skills. FDG-PET data were analyzed at single-subject level according to a standardized and validated voxel-based Statistical Parametric Mapping (SPM) method. Patients showed severe episodic memory and fear recognition deficits at the neuropsychological assessment. No disorder of mentalizing processing was present. Variable patterns of increases and decreases of brain glucose metabolism emerged in the limbic structures, highlighting the pathology-driven selective vulnerability of this system. Additional involvement of cortical and subcortical regions, particularly in the sensorimotor system and basal ganglia, was found. Episodic memory and fear recognition deficits characterize the cognitive profile of LE. Commonalities and differences may occur in the brain metabolic patterns. Single-subject voxel-based analysis of FDG-PET imaging could be useful in the early detection of the metabolic correlates of cognitive and non-cognitive deficits characterizing LE condition. Copyright © 2016 Elsevier Inc. All rights reserved.

Electro activation of persulfate using iron sheet as low-cost electrode: the role of the operating conditions.

PubMed

Silveira, Jefferson E; Cardoso, Tais O; Barreto-Rodrigues, Marcio; Zazo, Juan A; Casas, José A

2018-05-01

This work assesses the role of the operational conditions upon the electro-activation of persulfate (PS) using sacrificed iron electrode as a continuous low-cost Fe 2+ source. An aqueous phenol solution (100 mg L -1 ) was selected as model effluent. The studied variables include current density (1-10 mA cm -2 ), persulfate concentration (0.7-2.85 g L -1 ), temperature (30-90°C) and the solution conductivity (2.7-20.7 mS cm -1 ) using Na 2 SO 4 and NaCl as supporting electrolyte. A mineralization degree of around 80% with Na 2 SO 4 and 92% in presence of NaCl was achieved at 30°C using 2.15 g L -1 PS at the lowest current density tested (1 mA cm -2 ). Besides PS concentration, temperature was the main variable affecting the process. In the range of 30-70°C, it showed a positive effect, achieving TOC conversion above 95% (using Na 2 SO 4 under the previous conditions) along with a significant increase in iron sludge, which adversely affects the economy of the process. A lumped and simplified kinetic model based on persulfate consumption and TOC mineralization is suggested. The activation energy obtained for the TOC decay was 29 kJ mol -1 . An estimated operating cost of US$ 3.00 per m 3 was obtained, demonstrating the economic feasibility of this process.

Factors contributing to variability in larval ingress of Atlantic menhaden, Brevoortia tyrannus

NASA Astrophysics Data System (ADS)

Lozano, C.; Houde, E. D.

2013-02-01

Annual recruitment levels of age-0 juvenile Atlantic menhaden to Chesapeake Bay, which historically supported >65% of coastwide recruitment, have been consistently low since the 1980s. Diminished larval supply to the Bay is one hypothesized explanation. In a three-year ichthyoplankton survey at the Chesapeake Bay mouth, abundance of ingressing larvae varied nine-fold among years. Larvae were most abundant in 2007-2008 and less abundant in 2005-2006 and 2006-2007. High month-to-month variability in larval concentrations was attributable primarily to seasonality of occurrences. There was no defined spatial pattern in distribution of larvae across the 18-km-wide Bay mouth, but larvae at the south side were longer and older on average than larvae at the middle and north side. Environmental variables measured at the times of larval collections were not correlated consistently with temporal and spatial variability in abundance of larvae at ingress, highlighting complexity and suggesting that abundance may be controlled by processes occurring offshore during the pre-ingress phase. Moreover, the substantial differences in inter-annual abundances of larvae at the Bay mouth were not concordant with subsequent abundances of age-0 juveniles in the three survey years, indicating that important processes affecting recruitment of Atlantic menhaden operate after ingress, during the larval to juvenile transition stage.

Optimization of non-thermal plasma efficiency in the simultaneous elimination of benzene, toluene, ethyl-benzene, and xylene from polluted airstreams using response surface methodology.

PubMed

Najafpoor, Ali Asghar; Jonidi Jafari, Ahmad; Hosseinzadeh, Ahmad; Khani Jazani, Reza; Bargozin, Hasan

2018-01-01

Treatment with a non-thermal plasma (NTP) is a new and effective technology applied recently for conversion of gases for air pollution control. This research was initiated to optimize the efficient application of the NTP process in benzene, toluene, ethyl-benzene, and xylene (BTEX) removal. The effects of four variables including temperature, initial BTEX concentration, voltage, and flow rate on the BTEX elimination efficiency were investigated using response surface methodology (RSM). The constructed model was evaluated by analysis of variance (ANOVA). The model goodness-of-fit and statistical significance was assessed using determination coefficients (R 2 and R 2 adj ) and the F-test. The results revealed that the R 2 proportion was greater than 0.96 for BTEX removal efficiency. The statistical analysis demonstrated that the BTEX removal efficiency was significantly correlated with the temperature, BTEX concentration, voltage, and flow rate. Voltage was the most influential variable affecting the dependent variable as it exerted a significant effect (p < 0.0001) on the response variable. According to the achieved results, NTP can be applied as a progressive, cost-effective, and practical process for treatment of airstreams polluted with BTEX in conditions of low residence time and high concentrations of pollutants.

Image-Word Pairing-Congruity Effect on Affective Responses

NASA Astrophysics Data System (ADS)

Sanabria Z., Jorge C.; Cho, Youngil; Sambai, Ami; Yamanaka, Toshimasa

The present study explores the effects of familiarity on affective responses (pleasure and arousal) to Japanese ad elements, based on the schema incongruity theory. Print ads showing natural scenes (landscapes) were used to create the stimuli (images and words). An empirical study was conducted to measure subjects' affective responses to image-word combinations that varied in terms of incongruity. The level of incongruity was based on familiarity levels, and was statistically determined by a variable called ‘pairing-congruity status’. The tested hypothesis proposed that even highly familiar image-word combinations, when combined incongruously, would elicit strong affective responses. Subjects assessed the stimuli using bipolar scales. The study was effective in tracing interactions between familiarity, pleasure and arousal, although the incongruous image-word combinations did not elicit the predicted strong effects on pleasure and arousal. The results suggest a need for further research incorporating kansei (i.e., creativity) into the process of stimuli selection.

Hydrology, phenology and the USA National Phenology Network

USGS Publications Warehouse

Kish, George R.

2010-01-01

Phenology is the study of seasonally-recurring biological events (such as leaf-out, fruit production, and animal reproduction and migration) and how these events are influenced by environmental change. Phenological changes are some of the most sensitive biological indicators of climate change, and also affect nearly all aspects of ecosystem function. Spatially extensive patterns of phenological observations have been closely linked with climate variability. Phenology and hydrology are closely linked and affect one another across a variety of scales, from leaf intercellular spaces to the troposphere, and over periods of seconds to centuries. Ecosystem life cycles and diversity are also influenced by hydrologic processes such as floods and droughts. Therefore, understanding the relationships between hydrology and phenology is increasingly important in understanding how climate change affects biological and physical systems.

Variables Affecting Preservice Teacher Candidate Identification of Teacher Sexual Misconduct

ERIC Educational Resources Information Center

Haverland, Jeffrey A.

2017-01-01

Using a quantitative research model, this study explored variables affecting pre-service teacher candidate identification of teacher sexual misconduct through a scenario-based survey instrument. Independent variables in this study were respondent gender, student gender, teacher gender, student age-related ambiguity (students depicted were 17),…

Affective Variables Indicating Success for Compensatory Education Projects.

ERIC Educational Resources Information Center

Cavin, Alonzo; And Others

This document is a study of the importance of affective variables and the implications of these variables in student success or failure. A 28 item questionnaire was administered to 30 college students enrolled in a compensatory education program. The questionnaire assessed attitudes toward professors, administrators, peers, toward relevance of…

Effects of spatial structure of population size on the population dynamics of barnacles across their elevational range.

PubMed

Fukaya, Keiichi; Okuda, Takehiro; Nakaoka, Masahiro; Noda, Takashi

2014-11-01

Explanations for why population dynamics vary across the range of a species reflect two contrasting hypotheses: (i) temporal variability of populations is larger in the centre of the range compared to the margins because overcompensatory density dependence destabilizes population dynamics and (ii) population variability is larger near the margins, where populations are more susceptible to environmental fluctuations. In both of these hypotheses, positions within the range are assumed to affect population variability. In contrast, the fact that population variability is often related to mean population size implies that the spatial structure of the population size within the range of a species may also be a useful predictor of the spatial variation in temporal variability of population size over the range of the species. To explore how population temporal variability varies spatially and the underlying processes responsible for the spatial variation, we focused on the intertidal barnacle Chthamalus dalli and examined differences in its population dynamics along the tidal levels it inhabits. Changes in coverage of barnacle populations were monitored for 10.5 years at 25 plots spanning the elevational range of this species. Data were analysed by fitting a population dynamics model to estimate the effects of density-dependent and density-independent processes on population growth. We also examined the temporal mean-variance relationship of population size with parameters estimated from the population dynamics model. We found that the relative variability of populations tended to increase from the centre of the elevational range towards the margins because of an increase in the magnitude of stochastic fluctuations of growth rates. Thus, our results supported hypothesis (2). We also found that spatial variations in temporal population variability were well characterized by Taylor's power law, the relative population variability being inversely related to the mean population size. Results suggest that understanding the population dynamics of a species over its range may be facilitated by taking the spatial structure of population size into account as well as by considering changes in population processes as a function of position within the range of the species. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

Climate change hampers endangered species through intensified moisture-related plant stresses (Invited)

NASA Astrophysics Data System (ADS)

Bartholomeus, R.; Witte, J.; van Bodegom, P.; Dam, J. V.; Aerts, R.

2010-12-01

With recent climate change, extremes in meteorological conditions are forecast and observed to increase globally, and to affect vegetation composition. More prolonged dry periods will alternate with more intensive rainfall events, both within and between years, which will change soil moisture dynamics. In temperate climates, soil moisture, in concert with nutrient availability and soil acidity, is the most important environmental filter in determining local plant species composition, as it determines the availability of both oxygen and water to plant roots. These resources are indispensable for meeting the physiological demands of plants. The consequences of climate change for our natural environment are among the most pressing issues of our time. The international research community is beginning to realise that climate extremes may be more powerful drivers of vegetation change and species extinctions than slow-and-steady climatic changes, but the causal mechanisms of such changes are presently unknown. The roles of amplitudes in water availability as drivers of vegetation change have been particularly elusive owing to the lack of integration of the key variables involved. Here we show that the combined effect of increased rainfall variability, temperature and atmospheric CO2-concentration will lead to an increased variability in both wet and dry extremes in stresses faced by plants (oxygen and water stress, respectively). We simulated these plant stresses with a novel, process-based approach, incorporating in detail the interacting processes in the soil-plant-atmosphere interface. In order to quantify oxygen and water stress with causal measures, we focused on interacting meteorological, soil physical, microbial, and plant physiological processes in the soil-plant-atmosphere system. As both the supply and demand of oxygen and water depend strongly on the prevailing meteorological conditions, both oxygen and water stress were calculated dynamically in time to capture climate change effects. We demonstrate that increased rainfall variability in interaction with predicted changes in temperature and CO2, affects soil moisture conditions and plant oxygen and water demands such, that both oxygen stress and water stress will intensify due to climate change. Moreover, these stresses will increasingly coincide, causing variable stress conditions. These variable stress conditions were found to decrease future habitat suitability, especially for plant species that are presently endangered. The future existence of such species is thus at risk by climate change, which has direct implications for policies to maintain endangered species, as applied by international nature management organisations (e.g. IUCN). Our integrated mechanistic analysis of two stresses combined, which has never been done so far, reveals large impacts of climate change on species extinctions and thereby on biodiversity.

Smoking relapse situations among a community-recruited sample of Spanish daily smokers.

PubMed

Piñeiro, Bárbara; López-Durán, Ana; Martínez-Vispo, Carmela; Fernández Del Río, Elena; Martínez, Úrsula; Rodríguez-Cano, Rubén; Míguez, M Carmen; Becoña, Elisardo

2017-12-01

Relapse is a common factor within the behavior change process. However, there is scarce and limited knowledge of smoking relapse situations in population-based samples. The aim of this study was to identify smoking relapse situations among a sample of Spanish relapsers from the general population. A sample of 775 relapsers was recruited among the general population using a snowball method. Participants completed a survey including sociodemographic, smoking-related and psychopathology variables. Smoking relapse situations were identified through specific questions assessing different aspects related to the last relapse episode. The majority of smoking relapse situations were attributed to positive affect (36.6%) and negative affect (34.3%), followed by lack of control (10.1%), smoking habit (6.7%), craving or nicotine withdrawal (6.3%), and social pressure (5.9%). Being unemployed and having a mental disorder in the past increased the likelihood of relapse in situations of negative affect. Being single and having quit smoking to save money were associated with an increased likelihood of relapse in situations of positive affect. Affect plays a significant role in smoking relapse among a community sample of unassisted Spanish smokers. Relapse may be much more of an affective and situational process than a habit, physiological or social pressure. Findings from this study may help develop tailored community smoking relapse prevention strategies or programs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Affect in the "Communicative" Classroom: A Model.

ERIC Educational Resources Information Center

Acton, William

Recent research on affective variables and classroom second language learning suggests that: (1) affective variables are context-sensitive in at least two ways; (2) attitudes are contagious, and the general attitude of students can be influenced from various directions; (3) research in pragmatics, discourse analysis, and communicative functions…

Attention Induced Gain Stabilization in Broad and Narrow-Spiking Cells in the Frontal Eye-Field of Macaque Monkeys

PubMed Central

Brandt, Christian; Dasilva, Miguel; Gotthardt, Sascha; Chicharro, Daniel; Panzeri, Stefano; Distler, Claudia

2016-01-01

Top-down attention increases coding abilities by altering firing rates and rate variability. In the frontal eye field (FEF), a key area enabling top-down attention, attention induced firing rate changes are profound, but its effect on different cell types is unknown. Moreover, FEF is the only cortical area investigated in which attention does not affect rate variability, as assessed by the Fano factor, suggesting that task engagement affects cortical state nonuniformly. We show that putative interneurons in FEF of Macaca mulatta show stronger attentional rate modulation than putative pyramidal cells. Partitioning rate variability reveals that both cell types reduce rate variability with attention, but more strongly so in narrow-spiking cells. The effects are captured by a model in which attention stabilizes neuronal excitability, thereby reducing the expansive nonlinearity that links firing rate and variance. These results show that the effect of attention on different cell classes and different coding properties are consistent across the cortical hierarchy, acting through increased and stabilized neuronal excitability. SIGNIFICANCE STATEMENT Cortical processing is critically modulated by attention. A key feature of this influence is a modulation of “cortical state,” resulting in increased neuronal excitability and resilience of the network against perturbations, lower rate variability, and an increased signal-to-noise ratio. In the frontal eye field (FEF), an area assumed to control spatial attention in human and nonhuman primates, firing rate changes with attention occur, but rate variability, quantified by the Fano factor, appears to be unaffected by attention. Using recently developed analysis tools and models to quantify attention effects on narrow- and broad-spiking cell activity, we show that attention alters cortical state strongly in the FEF, demonstrating that its effect on the neuronal network is consistent across the cortical hierarchy. PMID:27445139

[Variability patterns of nest construction, physiological state, and morphometric traits in honey bee].

PubMed

Es'kov, E K; Es'kova, M D

2014-01-01

High variability of cells size is used selectively for reproduction of working bees and drones. A decrease in both distance between cells and cells size themselves causes similar effects to body mass and morphometric traits of developing individuals. Adaptation of honey bees to living in shelters has led to their becoming tolerant to hypoxia. Improvement of ethological and physiological mechanisms of thermal regulation is associated with limitation of ecological valence and acquiring of stenothermic features by breed. Optimal thermal conditions for breed are limited by the interval 33-34.5 degrees C. Deviations of temperature by 3-4 degrees C beyond this range have minimum lethal effect at embryonic stage of development and medium effect at the stage of pre-pupa and pupa. Developing at the low bound of the vital range leads to increasing, while developing at the upper bound--to decreasing of body mass, mandibular and hypopharyngeal glands, as well as other organs, which, later, affects the variability of these traits during the adult stage of development. Eliminative and teratogenic efficiency of ecological factors that affect a breed is most often manifested in underdevelopment of wings. However, their size (in case of wing laminas formation). is characterized by relatively low variability and size-dependent asymmetry. Asymmetry variability of wings and other pair organs is expressed through realignment of size excess from right- to left-side one with respect to their increase. Selective elimination by those traits whose emerging probability increases as developmental conditions deviate from the optimal ones promotes restrictions on individual variability. Physiological mechanisms that facilitate adaptability enhancement under conditions of increasing anthropogenic contamination of eivironment and trophic substrates consumed by honey bees, arrear to be toxicants accumulation in rectum and crops' ability to absorb contaminants from nectar in course of its processing to honey.

Impact of Monsoon to Aquatic Productivity and Fish Landing at Pesawaran Regency Waters

NASA Astrophysics Data System (ADS)

Kunarso; Zainuri, Muhammad; Ario, Raden; Munandar, Bayu; Prayogi, Harmon

2018-02-01

Monsoon variability influences the productivity processes in the ocean and has different responses in each waters. Furthermore, variability of marine productivity affects to the fisheries resources fluctuation. This research has conducted using descriptive method to investigate the consequences of monsoon variability to aquatic productivity, sea surface temperature (SST), fish catches, and fish season periods at Pesawaran Regency waters, Lampung. Variability of aquatic productivity was determined based on chlorophyll-a indicator from MODIS satellite images. Monsoon variability was governed based on wind parameters and fish catches from fish landing data of Pesawaran fish market. The result showed that monsoon variability had affected to aquatic productivity, SST, and fish catches at Pesawaran Regency waters. Maximum wind speed and lowest SST occurred twice in a year, December to March and August to October, which the peaks were on January (2.55 m/s of wind speed and 29.66°C of SST) and September (2.44 m/s of wind speed and 29.06°C of SST). Also, Maximum aquatic productivity happened on January to March and July to September, which it was arisen simultaneously with maximum wind speed and the peaks was 0.74 mg/m3 and 0.78 mg/m3, on February and August respectively. The data showed that fish catches decreased along with strong wind speed and low SST. However, when weak wind speed and high SST occurred, fish catches increased. The correlation between Catch per Unit Effort (CPUE) with SST, wind speed, and chlorophyll-a was at value 0.76, -0.67, and -0.70, respectively. The high rate fish catches in Pesawaran emerged on March-May and September-December.

Reflections on gifts in the therapeutic setting: the gift from patient to therapist.

PubMed

Smolar, Andrew I

2002-01-01

Since Freud's time, psychoanalytically oriented therapists have been wary of accepting gifts from patients, although they have done so in some circumstances within the sanctum of their offices. After providing a working definition of the word "gift" for the purposes of this clinical discussion, the article reviews the relevant literature on the subject. The author presents clinical material in which he describes how gifts were presented by patients within the context of their treatment processes. The article concludes with the author's attempt to define some of the variables that affect the response of the therapist to a patient's gift, and expounds on those variables in terms of their influence on technique.

Affect dynamics in relation to depressive symptoms: variable, unstable or inert?

PubMed

Koval, Peter; Pe, Madeline L; Meers, Kristof; Kuppens, Peter

2013-12-01

Depression not only involves disturbances in prevailing affect, but also in how affect fluctuates over time. Yet, precisely which patterns of affect dynamics are associated with depressive symptoms remains unclear; depression has been linked with increased affective variability and instability, but also with greater resistance to affective change (inertia). In this paper, we argue that these paradoxical findings stem from a number of neglected methodological/analytical factors, which we address using a novel paradigm and analytic approach. Participants (N = 99), preselected to represent a wide range of depressive symptoms, watched a series of emotional film clips and rated their affect at baseline and following each film clip. We also assessed participants' affect in daily life over 1 week using experience sampling. When controlling for overlap between different measures of affect dynamics, depressive symptoms were independently associated with higher inertia of negative affect in the lab, and with greater negative affect variability both in the lab and in daily life. In contrast, depressive symptoms were not independently related to higher affective instability either in daily life or in the lab.

The relationship between sleep-wake cycle and cognitive functioning in young people with affective disorders.

PubMed

Carpenter, Joanne S; Robillard, Rébecca; Lee, Rico S C; Hermens, Daniel F; Naismith, Sharon L; White, Django; Whitwell, Bradley; Scott, Elizabeth M; Hickie, Ian B

2015-01-01

Although early-stage affective disorders are associated with both cognitive dysfunction and sleep-wake disruptions, relationships between these factors have not been specifically examined in young adults. Sleep and circadian rhythm disturbances in those with affective disorders are considerably heterogeneous, and may not relate to cognitive dysfunction in a simple linear fashion. This study aimed to characterise profiles of sleep and circadian disturbance in young people with affective disorders and examine associations between these profiles and cognitive performance. Actigraphy monitoring was completed in 152 young people (16-30 years; 66% female) with primary diagnoses of affective disorders, and 69 healthy controls (18-30 years; 57% female). Patients also underwent detailed neuropsychological assessment. Actigraphy data were processed to estimate both sleep and circadian parameters. Overall neuropsychological performance in patients was poor on tasks relating to mental flexibility and visual memory. Two hierarchical cluster analyses identified three distinct patient groups based on sleep variables and three based on circadian variables. Sleep clusters included a 'long sleep' cluster, a 'disrupted sleep' cluster, and a 'delayed and disrupted sleep' cluster. Circadian clusters included a 'strong circadian' cluster, a 'weak circadian' cluster, and a 'delayed circadian' cluster. Medication use differed between clusters. The 'long sleep' cluster displayed significantly worse visual memory performance compared to the 'disrupted sleep' cluster. No other cognitive functions differed between clusters. These results highlight the heterogeneity of sleep and circadian profiles in young people with affective disorders, and provide preliminary evidence in support of a relationship between sleep and visual memory, which may be mediated by use of antipsychotic medication. These findings have implications for the personalisation of treatments and improvement of functioning in young adults early in the course of affective illness.

Interim results of quality-control sampling of surface water for the Upper Colorado River National Water-Quality Assessment Study Unit, water years 1995-96

USGS Publications Warehouse

Spahr, N.E.; Boulger, R.W.

1997-01-01

Quality-control samples provide part of the information needed to estimate the bias and variability that result from sample collection, processing, and analysis. Quality-control samples of surface water collected for the Upper Colorado River National Water-Quality Assessment study unit for water years 1995?96 are presented and analyzed in this report. The types of quality-control samples collected include pre-processing split replicates, concurrent replicates, sequential replicates, post-processing split replicates, and field blanks. Analysis of the pre-processing split replicates, concurrent replicates, sequential replicates, and post-processing split replicates is based on differences between analytical results of the environmental samples and analytical results of the quality-control samples. Results of these comparisons indicate that variability introduced by sample collection, processing, and handling is low and will not affect interpretation of the environmental data. The differences for most water-quality constituents is on the order of plus or minus 1 or 2 lowest rounding units. A lowest rounding unit is equivalent to the magnitude of the least significant figure reported for analytical results. The use of lowest rounding units avoids some of the difficulty in comparing differences between pairs of samples when concentrations span orders of magnitude and provides a measure of the practical significance of the effect of variability. Analysis of field-blank quality-control samples indicates that with the exception of chloride and silica, no systematic contamination of samples is apparent. Chloride contamination probably was the result of incomplete rinsing of the dilute cleaning solution from the outlet ports of the decaport sample splitter. Silica contamination seems to have been introduced by the blank water. Sampling and processing procedures for water year 1997 have been modified as a result of these analyses.

Investigation of the adhesion properties of direct 3D printing of polymers and nanocomposites on textiles: Effect of FDM printing process parameters

NASA Astrophysics Data System (ADS)

Hashemi Sanatgar, Razieh; Campagne, Christine; Nierstrasz, Vincent

2017-05-01

In this paper, 3D printing as a novel printing process was considered for deposition of polymers on synthetic fabrics to introduce more flexible, resource-efficient and cost effective textile functionalization processes than conventional printing process like screen and inkjet printing. The aim is to develop an integrated or tailored production process for smart and functional textiles which avoid unnecessary use of water, energy, chemicals and minimize the waste to improve ecological footprint and productivity. Adhesion of polymer and nanocomposite layers which were 3D printed directly onto the textile fabrics using fused deposition modeling (FDM) technique was investigated. Different variables which may affect the adhesion properties including 3D printing process parameters, fabric type and filler type incorporated in polymer were considered. A rectangular shape according to the peeling standard was designed as 3D computer-aided design (CAD) to find out the effect of the different variables. The polymers were printed in different series of experimental design: nylon on polyamide 66 (PA66) fabrics, polylactic acid (PLA) on PA66 fabric, PLA on PLA fabric, and finally nanosize carbon black/PLA (CB/PLA) and multi-wall carbon nanotubes/PLA (CNT/PLA) nanocomposites on PLA fabrics. The adhesion forces were quantified using the innovative sample preparing method combining with the peeling standard method. Results showed that different variables of 3D printing process like extruder temperature, platform temperature and printing speed can have significant effect on adhesion force of polymers to fabrics while direct 3D printing. A model was proposed specifically for deposition of a commercial 3D printer Nylon filament on PA66 fabrics. In the following, among the printed polymers, PLA and its composites had high adhesion force to PLA fabrics.

The role of psychosocial processes in the development and maintenance of chronic pain disorders

PubMed Central

Edwards, Robert R.; Dworkin, Robert H.; Sullivan, Mark D.; Turk, Dennis; Wasan, Ajay D.

2016-01-01

The recently-proposed ACTTION-APS Pain Taxonomy provides an evidence-based, multidimensional, chronic pain classification system. Psychosocial factors play a crucial role within several dimensions of the Taxonomy. In this paper, we discuss the evaluation of psychosocial factors that influence the diagnosis and trajectory of chronic pain disorders. We review studies in individuals with a variety of persistent pain conditions, and describe evidence that psychosocial variables play key roles in conferring risk for the development of pain, in shaping long-term pain-related adjustment, and in modulating pain treatment outcomes. We consider both “general” psychosocial variables such as negative affect, childhood trauma, and social support, as well as “pain-specific” psychosocial variables that include pain-related catastrophizing, self-efficacy for managing pain, and pain-related coping. Collectively, the complexity and profound variability in chronic pain highlights the need to better understand the multidimensional array of interacting forces that determine the trajectory of chronic pain conditions. PMID:27586832

Early warning of changing drinking water quality by trend analysis.

PubMed

Tomperi, Jani; Juuso, Esko; Leiviskä, Kauko

2016-06-01

Monitoring and control of water treatment plants play an essential role in ensuring high quality drinking water and avoiding health-related problems or economic losses. The most common quality variables, which can be used also for assessing the efficiency of the water treatment process, are turbidity and residual levels of coagulation and disinfection chemicals. In the present study, the trend indices are developed from scaled measurements to detect warning signs of changes in the quality variables of drinking water and some operating condition variables that strongly affect water quality. The scaling is based on monotonically increasing nonlinear functions, which are generated with generalized norms and moments. Triangular episodes are classified with the trend index and its derivative. Deviation indices are used to assess the severity of situations. The study shows the potential of the described trend analysis as a predictive monitoring tool, as it provides an advantage over the traditional manual inspection of variables by detecting changes in water quality and giving early warnings.

Long-duration drought variability and impacts on ecosystem services: A case study from Glacier National Park, Montana

USGS Publications Warehouse

Pederson, Gregory T.; Gray, Stephen T.; Fagre, Daniel B.; Graumlich, Lisa J.

2006-01-01

Using a suite of paleoproxy reconstructions and information from previous studies examining the relationship between climate variability and natural processes, the authors explore how such persistent moisture anomalies affect the delivery of vital goods and services provided by Glacier NP and surrounding areas. These analyses show that regional water resources and tourism are particularly vulnerable to persistent moisture anomalies in the Glacier NP area. Many of these same decadal-scale wet and dry events were also seen among a wider network of hydroclimatic reconstructions along a north–south transect of the Rocky Mountains. Such natural climate variability can, in turn, have enormous impacts on the sustainable provision of natural resources over wide areas. Overall, these results highlight the susceptibility of goods and services provided by protected areas like Glacier NP to natural climate variability, and show that this susceptibility will likely be compounded by the effects of future human-induced climate change.

More than Math: On the Affective Domain in Developmental Mathematics

ERIC Educational Resources Information Center

Guy, G. Michael; Cornick, Jonathan; Beckford, Ian

2015-01-01

Students at a large urban community college enrolled in fourteen sections of a developmental algebra class. While cognitive variables are often used to place students, affective characteristics may also influence their success. To explore the impact of affective variables, students took ACT's Engage survey measuring motivation, academic-related…

Treatment adherence and subjective well-being in HIV/AIDS infection.

PubMed

Reis, Ana Catarina Rodrigues da Silva; Guerra, Marina Natália Prista; Lencastre, Leonor Mendes de Freitas Queirós E

2013-01-01

The aim of this study was to analyze the relationship between treatment adherence and subjective well-being (positive and negative affects and satisfaction with life) in HIV/AIDS infection. The empirical study was conducted at two Portuguese hospitals (Porto and Lisbon) with a sample of 197 outpatients diagnosed with HIV/AIDS attending the Infectology service and on antiretroviral medication, during a 6-month period (February-July 2009). All patients were asked for voluntary fulfillment of the questionnaire which recorded information on different socio-demographic variables. Clinical records were inspected in order to collect additional clinical information from the patients. The "Questionnaire to Assess Adherence to Antiretroviral Treatment-HIV" was used in order to assess the adherence degree in Portuguese version of Reis et al. The Portuguese versions of "Positive and Negative Affect Schedule" (PANAS) and the "Satisfaction with Life Scale" were used to measure subjective well-being. The study collected evidence on the positive correlation between therapeutic adherence (assessed by CEAT-VIH) and positive affect, as well as between adherence and satisfaction with life. Differences in therapeutic adherence and positive affect according to some clinical variables were also found. The multiplicity and the interaction of several determinants are being considered in the adjustment process during treatment for HIV/AIDS. The results may have implications for the psychological intervention directed at improving adherence to antiretroviral therapy.

The theory, direction, and magnitude of ecosystem fire probability as constrained by precipitation and temperature.

PubMed

Guyette, Richard; Stambaugh, Michael C; Dey, Daniel; Muzika, Rose Marie

2017-01-01

The effects of climate on wildland fire confronts society across a range of different ecosystems. Water and temperature affect the combustion dynamics, irrespective of whether those are associated with carbon fueled motors or ecosystems, but through different chemical, physical, and biological processes. We use an ecosystem combustion equation developed with the physical chemistry of atmospheric variables to estimate and simulate fire probability and mean fire interval (MFI). The calibration of ecosystem fire probability with basic combustion chemistry and physics offers a quantitative method to address wildland fire in addition to the well-studied forcing factors such as topography, ignition, and vegetation. We develop a graphic analysis tool for estimating climate forced fire probability with temperature and precipitation based on an empirical assessment of combustion theory and fire prediction in ecosystems. Climate-affected fire probability for any period, past or future, is estimated with given temperature and precipitation. A graphic analyses of wildland fire dynamics driven by climate supports a dialectic in hydrologic processes that affect ecosystem combustion: 1) the water needed by plants to produce carbon bonds (fuel) and 2) the inhibition of successful reactant collisions by water molecules (humidity and fuel moisture). These two postulates enable a classification scheme for ecosystems into three or more climate categories using their position relative to change points defined by precipitation in combustion dynamics equations. Three classifications of combustion dynamics in ecosystems fire probability include: 1) precipitation insensitive, 2) precipitation unstable, and 3) precipitation sensitive. All three classifications interact in different ways with variable levels of temperature.

The theory, direction, and magnitude of ecosystem fire probability as constrained by precipitation and temperature

PubMed Central

Guyette, Richard; Stambaugh, Michael C.; Dey, Daniel

2017-01-01

The effects of climate on wildland fire confronts society across a range of different ecosystems. Water and temperature affect the combustion dynamics, irrespective of whether those are associated with carbon fueled motors or ecosystems, but through different chemical, physical, and biological processes. We use an ecosystem combustion equation developed with the physical chemistry of atmospheric variables to estimate and simulate fire probability and mean fire interval (MFI). The calibration of ecosystem fire probability with basic combustion chemistry and physics offers a quantitative method to address wildland fire in addition to the well-studied forcing factors such as topography, ignition, and vegetation. We develop a graphic analysis tool for estimating climate forced fire probability with temperature and precipitation based on an empirical assessment of combustion theory and fire prediction in ecosystems. Climate-affected fire probability for any period, past or future, is estimated with given temperature and precipitation. A graphic analyses of wildland fire dynamics driven by climate supports a dialectic in hydrologic processes that affect ecosystem combustion: 1) the water needed by plants to produce carbon bonds (fuel) and 2) the inhibition of successful reactant collisions by water molecules (humidity and fuel moisture). These two postulates enable a classification scheme for ecosystems into three or more climate categories using their position relative to change points defined by precipitation in combustion dynamics equations. Three classifications of combustion dynamics in ecosystems fire probability include: 1) precipitation insensitive, 2) precipitation unstable, and 3) precipitation sensitive. All three classifications interact in different ways with variable levels of temperature. PMID:28704457

28nm node process optimization: a lithography centric view

NASA Astrophysics Data System (ADS)

Seltmann, Rolf

2014-10-01

Many experts claim that the 28nm technology node will be the most cost effective technology node forever. This results from primarily from the cost of manufacturing due to the fact that 28nm is the last true Single Patterning (SP) node. It is also affected by the dramatic increase of design costs and the limited shrink factor of the next following nodes. Thus, it is assumed that this technology still will be alive still for many years. To be cost competitive, high yields are mandatory. Meanwhile, leading edge foundries have optimized the yield of the 28nm node to such a level that that it is nearly exclusively defined by random defectivity. However, it was a long way to go to come to that level. In my talk I will concentrate on the contribution of lithography to this yield learning curve. I will choose a critical metal patterning application. I will show what was needed to optimize the process window to a level beyond the usual OPC model work that was common on previous nodes. Reducing the process (in particular focus) variability is a complementary need. It will be shown which improvements were needed in tooling, process control and design-mask-wafer interaction to remove all systematic yield detractors. Over the last couple of years new scanner platforms were introduced that were targeted for both better productivity and better parametric performance. But this was not a clear run-path. It needed some extra affords of the tool suppliers together with the Fab to bring the tool variability down to the necessary level. Another important topic to reduce variability is the interaction of wafer none-planarity and lithography optimization. Having an accurate knowledge of within die topography is essential for optimum patterning. By completing both the variability reduction work and the process window enhancement work we were able to transfer the original marginal process budget to a robust positive budget and thus ensuring high yield and low costs.

[Quality of sleep and selective attention in university students: descriptive cross-sectional study].

PubMed

Fontana, Silvia Alicia; Raimondi, Waldina; Rizzo, María Laura

2014-09-05

Sleep quality not only refers to sleeping well at night, but also includes appropriate daytime functioning. Poor quality of sleep can affect a variety of attention processes. The aim of this investigation was to evaluate the relationship between the perceived quality of sleep and selective focus in a group of college students. A descriptive cross-sectional study was carried out in a group of 52 Argentinian college students of the Universidad Adventista del Plata. The Pittsburgh Sleep Quality Index, the Continuous Performance Test and the Trail Making Test were applied. The main results indicate that students sleep an average of 6.48 hours. Generally half of the population tested had a good quality of sleep. However, the dispersion seen in some components demonstrates the heterogeneity of the sample in these variables. It was observed that the evaluated attention processes yielded different levels of alteration in the total sample: major variability in the process of process and in the divided-attention processes were detected. A lower percentage of alteration was observed in the process of attention support. Poor quality of sleep has more impact in the sub processes with greater participation of corticocortical circuits (selective and divided attention) and greater involvement of the prefrontal cortex. Fewer difficulties were found in the attention-support processes that rely on subcortical regions and have less frontal involvement.

Rare Central Pacific El Niño Events Caused by Interdecadal Tropical Pacific Variability

NASA Astrophysics Data System (ADS)

Zhong, Wenxiu; Zheng, Xiaotong; Cai, Wenju

2017-04-01

The frequency of Central Pacific (CP) El Niño events displays strong decadal-variability but the associated dynamics is still not clear. The Inter-decadal Pacific Oscillation (IPO) and the Tropical Pacific Decadal Variability (TPDV) are two dominant modes of the Pacific low-frequency variability that can modify high-frequency behaviors. Using a 500-year control integration of Geophysical Fluid Dynamics Laboratory Earth System Model simulation, we find that the mean state, determined by the two independent modes of tropical Pacific decadal variability, strongly affects CP El Niño frequency and the associated developing processes. A positive TPDV features a shallow thermocline and cool sea surface temperature anomalies (SSTAs) across the central-to-western tropical Pacific, and a negative IPO features cool SSTAs and strong trade winds along the equatorial Pacific. The combination of a positive TPDV and a negative IPO generates a decadal mean state, in which the climatological zonal temperature gradient is reduced, equatorward and westward current anomalies are harder to be generated over the central-to-western tropical Pacific, resulting in the lack of CP El Niño.

Genetic variability in captive populations of the stingless bee Tetragonisca angustula.

PubMed

Santiago, Leandro R; Francisco, Flávio O; Jaffé, Rodolfo; Arias, Maria C

2016-08-01

Low genetic variability has normally been considered a consequence of animal husbandry and a major contributing factor to declining bee populations. Here, we performed a molecular analysis of captive and wild populations of the stingless bee Tetragonisca angustula, one of the most commonly kept species across South America. Microsatellite analyses showed similar genetic variability between wild and captive populations However, captive populations showed lower mitochondrial genetic variability. Male-mediated gene flow, transport and division of nests are suggested as the most probable explanations for the observed patterns of genetic structure. We conclude that increasing the number of colonies kept through nest divisions does not negatively affect nuclear genetic variability, which seems to be maintained by small-scale male dispersal and human-mediated nest transport. However, the transport of nests from distant localities should be practiced with caution given the high genetic differentiation observed between samples from western and eastern areas. The high genetic structure verified is the result of a long-term evolutionary process, and bees from distant localities may represent unique evolutionary lineages.

[Effect of emotional content and self reference of learning materials on recall performance].

PubMed

Spies, K

1994-01-01

It is assumed that high affective value and high self-reference of learning material help to improve memory performance as these factors allow better memory consolidation (activation hypothesis) or better integration of the new material into existing knowledge structures (extent-of-processing hypothesis). To test this assumption, 60 subjects were shown 16 short advertising films characterized by low vs. high affective value and low vs. high self-reference. Both factors were varied within subjects. After the films had each been presented twice, subjects had to recall the product names and answer two questions to each film. Results showed for both dependent variables that films with high affective values were better remembered than films with low affective values. The same held true--though to a lower extent--with respect to self-reference. According to the expected linear trend, performance was best for material scoring high on affective value as well as on self-reference, while it was worst for material scoring low on both factors.

Smoker Characteristics and Smoking-Cessation Milestones

PubMed Central

Japuntich, Sandra J.; Leventhal, Adam M.; Piper, Megan E.; Bolt, Daniel M.; Roberts, Linda J.; Fiore, Michael C.; Baker, Timothy B.

2011-01-01

Background Contextual variables often predict long-term abstinence, but little is known about how these variables exert their effects. These variables could influence abstinence by affecting the ability to quit at all, or by altering risk of lapsing, or progressing from a lapse to relapse. Purpose To examine the effect of common predictors of smoking-cessation failure on smoking-cessation processes. Methods The current study (N = 1504, 58% female, 84% Caucasian; recruited from January 2005 to June 2007; data analyzed in 2009) uses the approach advocated by Shiffman et al., (2006), which measures cessation outcomes on three different cessation milestones (achieving initial abstinence, lapse risk, and the lapse-relapse transition) to examine relationships of smoker characteristics (dependence, contextual and demographic factors) with smoking-cessation process. Results High nicotine dependence strongly predicted all milestones: not achieving initial abstinence, and a higher risk of both lapse and transitioning from lapse to complete relapse. Numerous contextual and demographic variables were associated with higher initial cessation rates and/or decreased lapse risk at 6 months post-quit (e.g., ethnicity, gender, marital status, education, smoking in the workplace, number of smokers in the social network, and number of supportive others). However, aside from nicotine dependence, only gender significantly predicted the risk of transition from lapse to relapse. Conclusions These findings demonstrate that: (1) higher nicotine dependence predicted worse outcomes across every cessation milestone; (2) demographic and contextual variables are generally associated with initial abstinence rates and lapse risk and not the lapse-relapse transition. These results identify groups who are at risk for failure at specific stages of the smoking-cessation process, and this may have implications for treatment. PMID:21335259

Higher-order Multivariable Polynomial Regression to Estimate Human Affective States

NASA Astrophysics Data System (ADS)

Wei, Jie; Chen, Tong; Liu, Guangyuan; Yang, Jiemin

2016-03-01

From direct observations, facial, vocal, gestural, physiological, and central nervous signals, estimating human affective states through computational models such as multivariate linear-regression analysis, support vector regression, and artificial neural network, have been proposed in the past decade. In these models, linear models are generally lack of precision because of ignoring intrinsic nonlinearities of complex psychophysiological processes; and nonlinear models commonly adopt complicated algorithms. To improve accuracy and simplify model, we introduce a new computational modeling method named as higher-order multivariable polynomial regression to estimate human affective states. The study employs standardized pictures in the International Affective Picture System to induce thirty subjects’ affective states, and obtains pure affective patterns of skin conductance as input variables to the higher-order multivariable polynomial model for predicting affective valence and arousal. Experimental results show that our method is able to obtain efficient correlation coefficients of 0.98 and 0.96 for estimation of affective valence and arousal, respectively. Moreover, the method may provide certain indirect evidences that valence and arousal have their brain’s motivational circuit origins. Thus, the proposed method can serve as a novel one for efficiently estimating human affective states.

Higher-order Multivariable Polynomial Regression to Estimate Human Affective States

PubMed Central

Wei, Jie; Chen, Tong; Liu, Guangyuan; Yang, Jiemin

2016-01-01

From direct observations, facial, vocal, gestural, physiological, and central nervous signals, estimating human affective states through computational models such as multivariate linear-regression analysis, support vector regression, and artificial neural network, have been proposed in the past decade. In these models, linear models are generally lack of precision because of ignoring intrinsic nonlinearities of complex psychophysiological processes; and nonlinear models commonly adopt complicated algorithms. To improve accuracy and simplify model, we introduce a new computational modeling method named as higher-order multivariable polynomial regression to estimate human affective states. The study employs standardized pictures in the International Affective Picture System to induce thirty subjects’ affective states, and obtains pure affective patterns of skin conductance as input variables to the higher-order multivariable polynomial model for predicting affective valence and arousal. Experimental results show that our method is able to obtain efficient correlation coefficients of 0.98 and 0.96 for estimation of affective valence and arousal, respectively. Moreover, the method may provide certain indirect evidences that valence and arousal have their brain’s motivational circuit origins. Thus, the proposed method can serve as a novel one for efficiently estimating human affective states. PMID:26996254

Child-related cognitions and affective functioning of physically abusive and comparison parents.

PubMed

Haskett, Mary E; Smith Scott, Susan; Grant, Raven; Ward, Caryn Sabourin; Robinson, Canby

2003-06-01

The goal of this research was to utilize the cognitive behavioral model of abusive parenting to select and examine risk factors to illuminate the unique and combined influences of social cognitive and affective variables in predicting abuse group membership. Participants included physically abusive parents (n=56) and a closely-matched group of comparison parents (n=62). Social cognitive risk variables measured were (a) parent's expectations for children's abilities and maturity, (b) parental attributions of intentionality of child misbehavior, and (c) parents' perceptions of their children's adjustment. Affective risk variables included (a) psychopathology and (b) parenting stress. A series of logistic regression models were constructed to test the individual, combined, and interactive effects of risk variables on abuse group membership. The full set of five risk variables was predictive of abuse status; however, not all variables were predictive when considered individually and interactions did not contribute significantly to prediction. A risk composite score computed for each parent based on the five risk variables significantly predicted abuse status. Wide individual differences in risk across the five variables were apparent within the sample of abusive parents. Findings were generally consistent with a cognitive behavioral model of abuse, with cognitive variables being more salient in predicting abuse status than affective factors. Results point to the importance of considering diversity in characteristics of abusive parents.

Reader variability in breast density estimation from full-field digital mammograms: the effect of image postprocessing on relative and absolute measures.

PubMed

Keller, Brad M; Nathan, Diane L; Gavenonis, Sara C; Chen, Jinbo; Conant, Emily F; Kontos, Despina

2013-05-01

Mammographic breast density, a strong risk factor for breast cancer, may be measured as either a relative percentage of dense (ie, radiopaque) breast tissue or as an absolute area from either raw (ie, "for processing") or vendor postprocessed (ie, "for presentation") digital mammograms. Given the increasing interest in the incorporation of mammographic density in breast cancer risk assessment, the purpose of this study is to determine the inherent reader variability in breast density assessment from raw and vendor-processed digital mammograms, because inconsistent estimates could to lead to misclassification of an individual woman's risk for breast cancer. Bilateral, mediolateral-oblique view, raw, and processed digital mammograms of 81 women were retrospectively collected for this study (N = 324 images). Mammographic percent density and absolute dense tissue area estimates for each image were obtained from two radiologists using a validated, interactive software tool. The variability of interreader agreement was not found to be affected by the image presentation style (ie, raw or processed, F-test: P > .5). Interreader estimates of relative and absolute breast density are strongly correlated (Pearson r > 0.84, P < .001) but systematically different (t-test, P < .001) between the two readers. Our results show that mammographic density may be assessed with equal reliability from either raw or vendor postprocessed images. Furthermore, our results suggest that the primary source of density variability comes from the subjectivity of the individual reader in assessing the absolute amount of dense tissue present in the breast, indicating the need to use standardized tools to mitigate this effect. Copyright © 2013 AUR. Published by Elsevier Inc. All rights reserved.

Organizational factors, planning capacity, and integration challenges constrain provincial planning processes for nutrition in decentralizing Vietnam.

PubMed

Lapping, Karin; Frongillo, Edward A; Nguyen, Phuong H; Coates, Jennifer; Webb, Patrick; Menon, Purnima

2014-09-01

Translating national policies and guidelines into effective action at the subnational level (e.g., province or region) is a prerequisite for ensuring an impact on nutrition. In several countries, including Vietnam, the focus of this paper, this process is affected by the quality of the decentralized process of planning and action. This study examined how provincial planning processes for nutrition occurred in Vietnam during 2009 and 2010. Key goals were to understand variability in processes across provinces, identify factors that influenced the process, and assess the usefulness of the process for individuals involved in planning and action. A qualitative case-study methodology was used. Data were drawn from interviews with 51 government officials in eight provinces. The study found little variability in the planning process among these eight provinces, probably due to a planning process that was predominantly a fiscal exercise within the confines of a largely centralized structure. Respondents were almost unanimous about the main barriers: a top-down approach to planning, limited human capacity for effective planning at subnational levels, and difficulty in integrating actions from multiple sectors. Provincial-level actors were deeply dissatisfied with the nature of their role in the process. Despite the rhetoric to the contrary, too much power is probably still retained at the central level. A strategic multiyear approach is needed to strengthen the provincial planning process and address many of the key barriers identified in this study.

Parallel Processing and Learning: Variability and Chaos in Self- Organization of Activity in Groups of Neurons

DTIC Science & Technology

1993-03-09

neurotransmission and neuromodulation (Soinila and Mpitsos, 1992; Soinila ct al., 1992). It is necessary, as these and other publications (e.g., Mpitsos and...neurotransmitters and neuromodulators affect the activity of neural assemblies, and (b) how individual transmitters act within the framework of the many...examined mammalian tissues that may he useful ajs model s~sqerni to examine distributed function in neurotransmission and neuromodulation (Soinila and

Cognitive reserve is not associated with improved performance in all cognitive domains.

PubMed

Lavrencic, Louise M; Churches, Owen F; Keage, Hannah A D

2017-06-08

Cognitive reserve beneficially affects cognitive performance, even into advanced age. However, the benefits afforded by high cognitive reserve may not extend to all cognitive domains. This study investigated whether cognitive reserve differentially affects performance on cognitive tasks, in 521 cognitively healthy individuals aged 60 to 98 years (Mage = 68, SD = 6.22, 287 female); years of education was used to index cognitive reserve. Cognitive performance variables assessed attention, executive functions, verbal memory, motor performance, orientation, perception of emotion, processing speed, and working memory. Bootstrapped regression analyses revealed that cognitive reserve was associated with attention, executive functions, verbal and working memory, and orientation; and not significantly related to emotion perception, processing speed, or motor performance. Cognitive reserve appears to differentially affect individual cognitive domains, which extends current theory that purports benefits for all domains. This finding highlights the possibility of using tests not (or minimally) associated with cognitive reserve, to screen for cognitive impairment and dementia in late life; these tests will likely best track brain health, free of compensatory neural mechanisms.

Analysis of factors driving stream water composition and synthesis of management tools--a case study on small/medium Greek catchments.

PubMed

Skoulikidis, N Th; Amaxidis, Y; Bertahas, I; Laschou, S; Gritzalis, K

2006-06-01

Twenty-nine small- and mid-sized permanent rivers (thirty-six sites) scattered throughout Greece and equally distributed within three geo-chemical-climatic zones, have been investigated in a seasonal base. Hydrochemical types have been determined and spatio-temporal variations have been interpreted in relation to environmental characteristics and anthropogenic pressures. Multivariate statistical techniques have been used to identify the factors and processes affecting hydrochemical variability and the driving forces that control aquatic composition. It has been shown that spatial variation of aquatic quality is mainly governed by geological and hydrogeological factors. Due to geological and climatic variability, the three zones have different hydrochemical characteristics. Temporal hydrological variations in combination with hydrogeological factors control seasonal hydrochemical trends. Respiration processes due to municipal wastewaters, dominate in summer, and enhance nutrient, chloride and sodium concentrations, while nitrate originates primarily from agriculture. Photosynthetic processes dominate in spring. Carbonate chemistry is controlled by hydrogeological factors and biological activity. A possible enrichment of surface waters with nutrients in "pristine" forested catchments is attributed to soil leaching and mineralisation processes. Two management tools have been developed: a nutrient classification system and a rapid prediction of aquatic composition tool.

Rebuilding DEMATEL threshold value: an example of a food and beverage information system.

PubMed

Hsieh, Yi-Fang; Lee, Yu-Cheng; Lin, Shao-Bin

2016-01-01

This study demonstrates how a decision-making trial and evaluation laboratory (DEMATEL) threshold value can be quickly and reasonably determined in the process of combining DEMATEL and decomposed theory of planned behavior (DTPB) models. Models are combined to identify the key factors of a complex problem. This paper presents a case study of a food and beverage information system as an example. The analysis of the example indicates that, given direct and indirect relationships among variables, if a traditional DTPB model only simulates the effects of the variables without considering that the variables will affect the original cause-and-effect relationships among the variables, then the original DTPB model variables cannot represent a complete relationship. For the food and beverage example, a DEMATEL method was employed to reconstruct a DTPB model and, more importantly, to calculate reasonable DEMATEL threshold value for determining additional relationships of variables in the original DTPB model. This study is method-oriented, and the depth of investigation into any individual case is limited. Therefore, the methods proposed in various fields of study should ideally be used to identify deeper and more practical implications.

Correlated bursts and the role of memory range

NASA Astrophysics Data System (ADS)

Jo, Hang-Hyun; Perotti, Juan I.; Kaski, Kimmo; Kertész, János

2015-08-01

Inhomogeneous temporal processes in natural and social phenomena have been described by bursts that are rapidly occurring events within short time periods alternating with long periods of low activity. In addition to the analysis of heavy-tailed interevent time distributions, higher-order correlations between interevent times, called correlated bursts, have been studied only recently. As the underlying mechanism behind such correlated bursts is far from being fully understood, we devise a simple model for correlated bursts using a self-exciting point process with a variable range of memory. Whether a new event occurs is stochastically determined by a memory function that is the sum of decaying memories of past events. In order to incorporate the noise and/or limited memory capacity of systems, we apply two memory loss mechanisms: a fixed number or a variable number of memories. By analysis and numerical simulations, we find that too much memory effect may lead to a Poissonian process, implying that there exists an intermediate range of memory effect to generate correlated bursts comparable to empirical findings. Our conclusions provide a deeper understanding of how long-range memory affects correlated bursts.

Using Multigroup-Multiphase Latent State-Trait Models to Study Treatment-Induced Changes in Intra-Individual State Variability: An Application to Smokers' Affect.

PubMed

Geiser, Christian; Griffin, Daniel; Shiffman, Saul

2016-01-01

Sometimes, researchers are interested in whether an intervention, experimental manipulation, or other treatment causes changes in intra-individual state variability. The authors show how multigroup-multiphase latent state-trait (MG-MP-LST) models can be used to examine treatment effects with regard to both mean differences and differences in state variability. The approach is illustrated based on a randomized controlled trial in which N = 338 smokers were randomly assigned to nicotine replacement therapy (NRT) vs. placebo prior to quitting smoking. We found that post quitting, smokers in both the NRT and placebo group had significantly reduced intra-individual affect state variability with respect to the affect items calm and content relative to the pre-quitting phase. This reduction in state variability did not differ between the NRT and placebo groups, indicating that quitting smoking may lead to a stabilization of individuals' affect states regardless of whether or not individuals receive NRT.

Using Multigroup-Multiphase Latent State-Trait Models to Study Treatment-Induced Changes in Intra-Individual State Variability: An Application to Smokers' Affect

PubMed Central

Geiser, Christian; Griffin, Daniel; Shiffman, Saul

2016-01-01

Sometimes, researchers are interested in whether an intervention, experimental manipulation, or other treatment causes changes in intra-individual state variability. The authors show how multigroup-multiphase latent state-trait (MG-MP-LST) models can be used to examine treatment effects with regard to both mean differences and differences in state variability. The approach is illustrated based on a randomized controlled trial in which N = 338 smokers were randomly assigned to nicotine replacement therapy (NRT) vs. placebo prior to quitting smoking. We found that post quitting, smokers in both the NRT and placebo group had significantly reduced intra-individual affect state variability with respect to the affect items calm and content relative to the pre-quitting phase. This reduction in state variability did not differ between the NRT and placebo groups, indicating that quitting smoking may lead to a stabilization of individuals' affect states regardless of whether or not individuals receive NRT. PMID:27499744

Harmonic analysis of the precipitation in Greece

NASA Astrophysics Data System (ADS)

Nastos, P. T.; Zerefos, C. S.

2009-04-01

Greece is a country with a big variety of climates due to its geographical position, to the many mountain ranges and also to the multifarious and long coastline. The mountainous volumes are of such orientation that influences the distribution of the precipitation, having as a result, Western Greece to present great differentiations from Central and Eastern Greece. The application of harmonic analysis to the annual variability of precipitation is the goal of this study, so that the components, which compose the annual variability, be elicited. For this purpose, the mean monthly precipitation data from 30 meteorological stations of National Meteorological Service were used for the time period 1950-2000. The initial target is to reduce the number of variables and to detect structure in the relationships between variables. The most commonly used technique for this purpose is the application of Factor Analysis to a table having as columns the meteorological stations-variables and rows the monthly mean precipitation, so that 2 main factors were calculated, which explain the 98% of total variability of precipitation in Greece. Factor 1, representing the so-called uniform field and interpreting the most of the total variance, refers in fact to the Mediterranean depressions, affecting mainly the West of Greece and also the East Aegean and the Asia Minor coasts. In the process, the Fourier Analysis was applied to the factor scores extracted from the Factor Analysis, so that 2 harmonic components are resulted, which explain above the 98% of the total variability of each main factor, and are due to different synoptic and thermodynamic processes associated with Greece's precipitation construction. Finally, the calculation of the time of occurrence of the maximum precipitation, for each harmonic component of each one of the two main factors, gives the spatial distribution of appearance of the maximum precipitation in the Hellenic region.

An approach to understanding hydrologic connectivity on the hillslope and the implications for nutrient transport

USGS Publications Warehouse

Stieglitz, M.; Shaman, J.; McNamara, J.; Engel, V.; Shanley, J.; Kling, G.W.

2003-01-01

Hydrologic processes control much of the export of organic matter and nutrients from the land surface. It is the variability of these hydrologic processes that produces variable patterns of nutrient transport in both space and time. In this paper, we explore how hydrologic "connectivity" potentially affects nutrient transport. Hydrologic connectivity is defined as the condition by which disparate regions on the hillslope are linked via subsurface water flow. We present simulations that suggest that for much of the year, water draining through a catchment is spatially isolated. Only rarely, during storm and snowmelt events when antecedent soil moisture is high, do our simulations suggest that mid-slope saturation (or near saturation) occurs and that a catchment connects from ridge to valley. Observations during snowmelt at a small headwater catchment in Idaho are consistent with these model simulations. During early season discharge episodes, in which the mid-slope soil column is not saturated, the electrical conductivity in the stream remains low, reflecting a restricted, local (lower slope) source of stream water and the continued isolation of upper and mid-slope soil water and nutrients from the stream system. Increased streamflow and higher stream water electrical conductivity, presumably reflecting the release of water from the upper reaches of the catchment, are simultaneously observed when the mid-slope becomes sufficiently wet. This study provides preliminary evidence that the seasonal timing of hydrologic connectivity may affect a range of ecological processes, including downslope nutrient transport, C/N cycling, and biological productivity along the toposequence. A better elucidation of hydrologic connectivity will be necessary for understanding local processes as well as material export from land to water at regional and global scales. Copyright 2003 by the American Geophysical Union.

Long-Term Study of Heart Rate Variability Responses to Changes in the Solar and Geomagnetic Environment.

PubMed

Alabdulgader, Abdullah; McCraty, Rollin; Atkinson, Michael; Dobyns, York; Vainoras, Alfonsas; Ragulskis, Minvydas; Stolc, Viktor

2018-02-08

This long-term study examined relationships between solar and magnetic factors and the time course and lags of autonomic nervous system (ANS) responses to changes in solar and geomagnetic activity. Heart rate variability (HRV) was recorded for 72 consecutive hours each week over a five-month period in 16 participants in order to examine ANS responses during normal background environmental periods. HRV measures were correlated with solar and geomagnetic variables using multivariate linear regression analysis with Bonferroni corrections for multiple comparisons after removing circadian influences from both datasets. Overall, the study confirms that daily ANS activity responds to changes in geomagnetic and solar activity during periods of normal undisturbed activity and it is initiated at different times after the changes in the various environmental factors and persist over varying time periods. Increase in solar wind intensity was correlated with increases in heart rate, which we interpret as a biological stress response. Increase in cosmic rays, solar radio flux, and Schumann resonance power was all associated with increased HRV and parasympathetic activity. The findings support the hypothesis that energetic environmental phenomena affect psychophysical processes that can affect people in different ways depending on their sensitivity, health status and capacity for self-regulation.

Relationship between cardiac autonomic function and cognitive function in Alzheimer's disease.

PubMed

Nonogaki, Zen; Umegaki, Hiroyuki; Makino, Taeko; Suzuki, Yusuke; Kuzuya, Masafumi

2017-01-01

Alzheimer's disease (AD) affects many central nervous structures and neurotransmitter systems. These changes affect not only cognitive function, but also cardiac autonomic function. However, the functional relationship between cardiac autonomic function and cognition in AD has not yet been investigated. The objective of the present study was to evaluate the association between cardiac autonomic function measured by heart rate variability and cognitive function in AD. A total of 78 AD patients were recruited for this study. Cardiac autonomic function was evaluated using heart rate variability analysis. Multiple linear regression analysis was used to model the association between heart rate variability and cognitive function (global cognitive function, memory, executive function and processing speed), after adjustment for covariates. Global cognitive function was negatively associated with sympathetic modulation (low-to-high frequency power ratio). Memory performance was positively associated with parasympathetic modulation (high frequency power) and negatively associated with sympathetic modulation (low-to-high frequency power ratio). These associations were independent of age, sex, educational years, diabetes, hypertension and cholinesterase inhibitor use. Cognitive function, especially in the areas of memory, is associated with cardiac autonomic function in AD. Specifically, lower cognitive performance was found to be associated with significantly higher cardiac sympathetic and lower parasympathetic function in AD. Geriatr Gerontol Int 2017; 17: 92-98. © 2015 Japan Geriatrics Society.

Characterization and optimization of cell seeding in scaffolds by factorial design: quality by design approach for skeletal tissue engineering.

PubMed

Chen, Yantian; Bloemen, Veerle; Impens, Saartje; Moesen, Maarten; Luyten, Frank P; Schrooten, Jan

2011-12-01

Cell seeding into scaffolds plays a crucial role in the development of efficient bone tissue engineering constructs. Hence, it becomes imperative to identify the key factors that quantitatively predict reproducible and efficient seeding protocols. In this study, the optimization of a cell seeding process was investigated using design of experiments (DOE) statistical methods. Five seeding factors (cell type, scaffold type, seeding volume, seeding density, and seeding time) were selected and investigated by means of two response parameters, critically related to the cell seeding process: cell seeding efficiency (CSE) and cell-specific viability (CSV). In addition, cell spatial distribution (CSD) was analyzed by Live/Dead staining assays. Analysis identified a number of statistically significant main factor effects and interactions. Among the five seeding factors, only seeding volume and seeding time significantly affected CSE and CSV. Also, cell and scaffold type were involved in the interactions with other seeding factors. Within the investigated ranges, optimal conditions in terms of CSV and CSD were obtained when seeding cells in a regular scaffold with an excess of medium. The results of this case study contribute to a better understanding and definition of optimal process parameters for cell seeding. A DOE strategy can identify and optimize critical process variables to reduce the variability and assists in determining which variables should be carefully controlled during good manufacturing practice production to enable a clinically relevant implant.

Multivariate Models of Adult Pacific Salmon Returns

PubMed Central

Burke, Brian J.; Peterson, William T.; Beckman, Brian R.; Morgan, Cheryl; Daly, Elizabeth A.; Litz, Marisa

2013-01-01

Most modeling and statistical approaches encourage simplicity, yet ecological processes are often complex, as they are influenced by numerous dynamic environmental and biological factors. Pacific salmon abundance has been highly variable over the last few decades and most forecasting models have proven inadequate, primarily because of a lack of understanding of the processes affecting variability in survival. Better methods and data for predicting the abundance of returning adults are therefore required to effectively manage the species. We combined 31 distinct indicators of the marine environment collected over an 11-year period into a multivariate analysis to summarize and predict adult spring Chinook salmon returns to the Columbia River in 2012. In addition to forecasts, this tool quantifies the strength of the relationship between various ecological indicators and salmon returns, allowing interpretation of ecosystem processes. The relative importance of indicators varied, but a few trends emerged. Adult returns of spring Chinook salmon were best described using indicators of bottom-up ecological processes such as composition and abundance of zooplankton and fish prey as well as measures of individual fish, such as growth and condition. Local indicators of temperature or coastal upwelling did not contribute as much as large-scale indicators of temperature variability, matching the spatial scale over which salmon spend the majority of their ocean residence. Results suggest that effective management of Pacific salmon requires multiple types of data and that no single indicator can represent the complex early-ocean ecology of salmon. PMID:23326586

Examining Affect and Perfectionism in Relation to Eating Disorder Symptoms among Women with Anorexia Nervosa

PubMed Central

Lavender, Jason M.; Mason, Tyler B.; Utzinger, Linsey M.; Wonderlich, Stephen A.; Crosby, Ross D.; Engel, Scott G.; Mitchell, James E.; Le Grange, Daniel; Crow, Scott J.; Peterson, Carol B.

2016-01-01

This study examined personality and affective variables in relation to eating disorder symptoms in anorexia nervosa (AN). Women (N=118) with DSM-IV AN completed baseline questionnaires (Beck Depression Inventory, Frost Multidimensional Perfectionism Scale) and interviews (Eating Disorder Examination, Yale-Brown-Cornell Eating Disorder Scale), followed by two weeks of ecological momentary assessment (EMA) involving multiple daily reports of affective states and eating disorder behaviors. Hierarchical regression analyses were conducted using eating disorder symptoms as dependent variables (i.e., EMA binge eating, EMA self-induced vomiting, eating disorder rituals, eating disorder preoccupations, dietary restraint). Predictor variables were maladaptive perfectionism (baseline), depressive symptoms (baseline), and affect lability (EMA). Results revealed that affect lability was independently associated with binge eating, whereas depressive symptoms were independently associated with self-induced vomiting. Depressive symptoms were independently associated with eating disorder rituals, whereas both depressive symptoms and maladaptive perfectionism were independently associated with eating disorder preoccupations. Finally, maladaptive perfectionism and affect lability were both independently associated with dietary restraint. This pattern of findings suggests the importance of affective and personality constructs in relation to eating disorder symptoms in AN and may highlight the importance of targeting these variables in the context of treatment. PMID:27208513

Real Time Land-Surface Hydrologic Modeling Over Continental US

NASA Technical Reports Server (NTRS)

Houser, Paul R.

1998-01-01

The land surface component of the hydrological cycle is fundamental to the overall functioning of the atmospheric and climate processes. Spatially and temporally variable rainfall and available energy, combined with land surface heterogeneity cause complex variations in all processes related to surface hydrology. The characterization of the spatial and temporal variability of water and energy cycles are critical to improve our understanding of land surface-atmosphere interaction and the impact of land surface processes on climate extremes. Because the accurate knowledge of these processes and their variability is important for climate predictions, most Numerical Weather Prediction (NWP) centers have incorporated land surface schemes in their models. However, errors in the NWP forcing accumulate in the surface and energy stores, leading to incorrect surface water and energy partitioning and related processes. This has motivated the NWP to impose ad hoc corrections to the land surface states to prevent this drift. A proposed methodology is to develop Land Data Assimilation schemes (LDAS), which are uncoupled models forced with observations, and not affected by NWP forcing biases. The proposed research is being implemented as a real time operation using an existing Surface Vegetation Atmosphere Transfer Scheme (SVATS) model at a 40 km degree resolution across the United States to evaluate these critical science questions. The model will be forced with real time output from numerical prediction models, satellite data, and radar precipitation measurements. Model parameters will be derived from the existing GIS vegetation and soil coverages. The model results will be aggregated to various scales to assess water and energy balances and these will be validated with various in-situ observations.

Reducing the negative effects of emotion work in service occupations: emotional competence as a psychological resource.

PubMed

Giardini, Angelo; Frese, Michael

2006-01-01

Although emotion work and emotional competence focus on similar processes, there has been a lack of integration between the 2 concepts. Emotion work is the regulatory effort to express organizationally desired emotions, whereas emotional competence encompasses skills that focus on how people deal with and regulate their own affect and that of others. The general hypothesis of this study was that emotional competence can be regarded as an important personal resource in emotion work because it moderates the relationships between work characteristics, emotional dissonance, and outcome variables. Eighty-four service employees completed a questionnaire on their working conditions and their well-being. In addition, peer ratings for emotional competence were completed. The authors found that emotional competence moderated most of the proposed relationships between work characteristics and emotional dissonance, between emotional dissonance and outcome variables, and between work characteristics and outcome variables. Copyright 2006 APA.

Excessive motor overflow reveals abnormal inter-hemispheric connectivity in Friedreich ataxia.

PubMed

Low, Sze-Cheen; Corben, Louise A; Delatycki, Martin B; Ternes, Anne-Marie; Addamo, Patricia K; Georgiou-Karistianis, Nellie

2013-07-01

This study sought to characterise force variability and motor overflow in 12 individuals with Friedreich ataxia (FRDA) and 12 age- and gender-matched controls. Participants performed a finger-pressing task by exerting 30 and 70 % of their maximum finger force using the index finger of the right and left hand. Control of force production was measured as force variability, while any involuntary movements occurring on the finger of the other, passive hand, was measured as motor overflow. Significantly greater force variability in individuals with FRDA compared with controls is indicative of cortico-cerebellar disruption affecting motor control. Meanwhile, significantly greater motor overflow in this group provides the first evidence of possible abnormal inter-hemispheric activity that may be attributable to asymmetrical neuronal loss in the dentate nucleus. Overall, this study demonstrated a differential engagement in the underlying default processes of the motor system in FRDA.

Variability at the edge: highly accreting objects in Taurus

NASA Astrophysics Data System (ADS)

Abraham, Peter; Kospal, Agnes; Szabo, Robert

2017-04-01

In Kepler K2, Campaign 13, we will obtain 80-days-long optical light curves of seven highly accreting T Tauri stars in the benchmark Taurus star forming region. Here we propose to monitor our sample simultaneously with Kepler and Spitzer, to be able to separate variability patterns related to different physical processes. Monitoring our targets with Spitzer during the final 11 days of the K2 campaign, we will clean the light curves from non-accretion effects (rotating stellar spots, dips due to passing dust structures), and construct, for the first time, a variability curve which reflects the time-dependent accretion only. We will then study and understand how time-dependent mass accretion affects the density and temperature structure of the protoplanetary disk, which sets the initial conditions for planet formation. The proposed work cannot be done without the unparalleled precision of Kepler and Spitzer. This unique and one-time opportunity motivated our DDT proposal.

Brain Signal Variability Differentially Affects Cognitive Flexibility and Cognitive Stability.

PubMed

Armbruster-Genç, Diana J N; Ueltzhöffer, Kai; Fiebach, Christian J

2016-04-06

Recent research yielded the intriguing conclusion that, in healthy adults, higher levels of variability in neuronal processes are beneficial for cognitive functioning. Beneficial effects of variability in neuronal processing can also be inferred from neurocomputational theories of working memory, albeit this holds only for tasks requiring cognitive flexibility. However, cognitive stability, i.e., the ability to maintain a task goal in the face of irrelevant distractors, should suffer under high levels of brain signal variability. To directly test this prediction, we studied both behavioral and brain signal variability during cognitive flexibility (i.e., task switching) and cognitive stability (i.e., distractor inhibition) in a sample of healthy human subjects and developed an efficient and easy-to-implement analysis approach to assess BOLD-signal variability in event-related fMRI task paradigms. Results show a general positive effect of neural variability on task performance as assessed by accuracy measures. However, higher levels of BOLD-signal variability in the left inferior frontal junction area result in reduced error rate costs during task switching and thus facilitate cognitive flexibility. In contrast, variability in the same area has a detrimental effect on cognitive stability, as shown in a negative effect of variability on response time costs during distractor inhibition. This pattern was mirrored at the behavioral level, with higher behavioral variability predicting better task switching but worse distractor inhibition performance. Our data extend previous results on brain signal variability by showing a differential effect of brain signal variability that depends on task context, in line with predictions from computational theories. Recent neuroscientific research showed that the human brain signal is intrinsically variable and suggested that this variability improves performance. Computational models of prefrontal neural networks predict differential effects of variability for different behavioral situations requiring either cognitive flexibility or stability. However, this hypothesis has so far not been put to an empirical test. In this study, we assessed cognitive flexibility and cognitive stability, and, besides a generally positive effect of neural variability on accuracy measures, we show that neural variability in a prefrontal brain area at the inferior frontal junction is differentially associated with performance: higher levels of variability are beneficial for the effectiveness of task switching (cognitive flexibility) but detrimental for the efficiency of distractor inhibition (cognitive stability). Copyright © 2016 the authors 0270-6474/16/363978-10$15.00/0.

Understanding Narrative Effects: The Impact of Breast Cancer Survivor Stories on Message Processing, Attitudes, and Beliefs among African American Women

PubMed Central

McQueen, Amy; Kreuter, Matthew W.; Kalesan, Bindu; Alcaraz, Kassandra I.

2011-01-01

OBJECTIVE Examine the longitudinal effects of personal narratives about mammography and breast cancer compared with a traditional informational approach. METHOD African American women (n=489) ages 40 and older were recruited from low-income neighborhoods in St. Louis, MO and randomized to watch a narrative video comprised of stories from African American breast cancer survivors or a content-equivalent informational video. Effects were measured immediately post-exposure (T2) and at 3- (T3) and 6-month (T4) follow-up. T2 measures of initial reaction included positive and negative affect, trust, identification, and engagement. T3 message-processing variables included arguing against the messages (counterarguing) and talking to family members about the information (cognitive rehearsal). T4 behavioral correlates included perceived breast cancer risk, cancer fear, cancer fatalism, perceived barriers to mammography, and recall of core messages. Structural equation modeling examined inter-relations among constructs. RESULTS Women who watched the narrative video (n=244) compared to the informational video (n=245) experienced more positive and negative affect, identified more with the message source, and were more engaged with the video. Narratives, negative affect, identification, and engagement influenced counterarguing, which in turn influenced perceived barriers and cancer fatalism. More engaged women talked with family members more, which increased message recall. Narratives also increased risk perceptions and fear via increased negative affect. CONCLUSIONS Narratives produced stronger cognitive and affective responses immediately, which in turn influenced message processing and behavioral correlates. Narratives reduced counterarguing and increased cognitive rehearsal, which may increase acceptance and motivation to act on health information in populations most adversely affected by cancer disparities. PMID:21895370

Excess Vitamin Intake before Starvation does not Affect Body Mass, Organ Mass, or Blood Variables but Affects Urinary Excretion of Riboflavin in Starving Rats.

PubMed

Moriya, Aya; Fukuwatari, Tsutomu; Shibata, Katsumi

2013-01-01

B-vitamins are important for producing energy from amino acids, fatty acids, and glucose. The aim of this study was to elucidate the effects of excess vitamin intake before starvation on body mass, organ mass, blood, and biological variables as well as on urinary excretion of riboflavin in rats. Adult rats were fed two types of diets, one with a low vitamin content (minimum vitamin diet for optimum growth) and one with a sufficient amount of vitamins (excess vitamin diet). Body mass, organ mass, and blood variables were not affected by excess vitamin intake before starvation. Interestingly, urinary riboflavin excretion showed a different pattern. Urine riboflavin in the excess vitamin intake group declined gradually during starvation, whereas it increased in the low vitamin intake group. Excess vitamin intake before starvation does not affect body mass, organ mass, or blood variables but does affect the urinary excretion of riboflavin in starving rats.