Tacit knowledge as the unifying factor in evidence based medicine and clinical judgement

PubMed Central

Thornton, Tim

2006-01-01

The paper outlines the role that tacit knowledge plays in what might seem to be an area of knowledge that can be made fully explicit or codified and which forms a central element of Evidence Based Medicine. Appeal to the role the role of tacit knowledge in science provides a way to unify the tripartite definition of Evidence Based Medicine given by Sackett et al: the integration of best research evidence with clinical expertise and patient values. Each of these three elements, crucially including research evidence, rests on an ineliminable and irreducible notion of uncodified good judgement. The paper focuses on research evidence, drawing first on the work of Kuhn to suggest that tacit knowledge contributes, as a matter of fact, to puzzle solving within what he calls normal science. A stronger argument that it must play a role in research is first motivated by looking to Collins' first hand account of replication in applied physics and then broader considerations of replication in justifying knowledge claims in scientific research. Finally, consideration of an argument from Wittgenstein shows that whatever explicit guidelines can be drawn up to guide judgement the specification of what counts as correctly following them has to remain implicit. Overall, the paper sets out arguments for the claim that even though explicit guidelines and codifications can play a practical role in informing clinical practice, they rest on a body of tacit or implicit skill that is in principle ineliminable. It forms the bedrock of good judgement and unites the integration of research, expertise and values. PMID:16759426

Technology Considerations for Inclusion of Survivability in MDAO

NASA Technical Reports Server (NTRS)

Alexandrov, Natalia M.

2017-01-01

Rising traffic density, along with autonomy and diversity of vehicles in the air, will fundamentally change the safety environment of the future air transportation system. The change in risk is two-fold: increasing chances of mid-air collisions with non-cooperative objects and increasing chances of crashes over highly populated areas. The changing nature of the vehicles populating the airspace means that civilian aircraft design must now explicitly include considerations of survivability in the event of collision with other vehicles, as well as prevention of damage to people, animals and property on the ground, to a much greater extent than today. This paper offers a preliminary perspective on how MDAO could contribute toward these goals. One of the conclusions is that, in contrast to traditional vehicle design, to accommodate the complexity of the future airspace safely and efficiently, vehicle design requirements, modeling, and design optimization must be closely connected to the properties of the airspace, including those of other vehicles in the air. Thus, the total measure of a vehicle's survivability should include the traditional survivability in malfunction scenarios, combined with new considerations of survivability in collisions and survivability of the public on the ground.

Special-case closed form of the Baker-Campbell-Hausdorff formula

NASA Astrophysics Data System (ADS)

Van-Brunt, Alexander; Visser, Matt

2015-06-01

The Baker-Campbell-Hausdorff formula is a general result for the quantity Z(X,Y)=ln ({{e}X}{{e}Y}), where X and Y are not necessarily commuting. For completely general commutation relations between X and Y, (the free Lie algebra), the general result is somewhat unwieldy. However in specific physics applications the commutator [X,Y], while non-zero, might often be relatively simple, which sometimes leads to explicit closed form results. We consider the special case [X,Y]=uX+vY+cI, and show that in this case the general result reduces to Furthermore we explicitly evaluate the symmetric function f(u,v)=f(v,u), demonstrating that and relate this to previously known results. For instance this result includes, but is considerably more general than, results obtained from either the Heisenberg commutator [P,Q]=-i\\hbar I or the creation-destruction commutator [a,{{a}\\dagger }]=I.

A Comparison of the neural correlates that underlie rule-based and information-integration category learning.

PubMed

Carpenter, Kathryn L; Wills, Andy J; Benattayallah, Abdelmalek; Milton, Fraser

2016-10-01

The influential competition between verbal and implicit systems (COVIS) model proposes that category learning is driven by two competing neural systems-an explicit, verbal, system, and a procedural-based, implicit, system. In the current fMRI study, participants learned either a conjunctive, rule-based (RB), category structure that is believed to engage the explicit system, or an information-integration category structure that is thought to preferentially recruit the implicit system. The RB and information-integration category structures were matched for participant error rate, the number of relevant stimulus dimensions, and category separation. Under these conditions, considerable overlap in brain activation, including the prefrontal cortex, basal ganglia, and the hippocampus, was found between the RB and information-integration category structures. Contrary to the predictions of COVIS, the medial temporal lobes and in particular the hippocampus, key regions for explicit memory, were found to be more active in the information-integration condition than in the RB condition. No regions were more activated in RB than information-integration category learning. The implications of these results for theories of category learning are discussed. Hum Brain Mapp 37:3557-3574, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Economic evaluation of targeted cancer interventions: critical review and recommendations.

PubMed

Elkin, Elena B; Marshall, Deborah A; Kulin, Nathalie A; Ferrusi, Ilia L; Hassett, Michael J; Ladabaum, Uri; Phillips, Kathryn A

2011-10-01

Scientific advances have improved our ability to target cancer interventions to individuals who will benefit most and spare the risks and costs to those who will derive little benefit or even be harmed. Several approaches are currently used for targeting interventions for cancer risk reduction, screening, and treatment, including risk prediction algorithms for identifying high-risk subgroups and diagnostic tests for tumor markers and germline genetic mutations. Economic evaluation can inform decisions about the use of targeted interventions, which may be more costly than traditional strategies. However, assessing the impact of a targeted intervention on costs and health outcomes requires explicit consideration of the method of targeting. In this study, we describe the importance of this principle by reviewing published cost-effectiveness analyses of targeted interventions in breast cancer. Few studies we identified explicitly evaluated the relationships among the method of targeting, the accuracy of the targeting test, and outcomes of the targeted intervention. Those that did found that characteristics of targeting tests had a substantial impact on outcomes. We posit that the method of targeting and the outcomes of a targeted intervention are inextricably linked and recommend that cost-effectiveness analyses of targeted interventions explicitly consider costs and outcomes of the method of targeting.

An image-based skeletal dosimetry model for the ICRP reference adult male—internal electron sources

NASA Astrophysics Data System (ADS)

Hough, Matthew; Johnson, Perry; Rajon, Didier; Jokisch, Derek; Lee, Choonsik; Bolch, Wesley

2011-04-01

In this study, a comprehensive electron dosimetry model of the adult male skeletal tissues is presented. The model is constructed using the University of Florida adult male hybrid phantom of Lee et al (2010 Phys. Med. Biol. 55 339-63) and the EGSnrc-based Paired Image Radiation Transport code of Shah et al (2005 J. Nucl. Med. 46 344-53). Target tissues include the active bone marrow, associated with radiogenic leukemia, and total shallow marrow, associated with radiogenic bone cancer. Monoenergetic electron emissions are considered over the energy range 1 keV to 10 MeV for the following sources: bone marrow (active and inactive), trabecular bone (surfaces and volumes), and cortical bone (surfaces and volumes). Specific absorbed fractions are computed according to the MIRD schema, and are given as skeletal-averaged values in the paper with site-specific values reported in both tabular and graphical format in an electronic annex available from http://stacks.iop.org/0031-9155/56/2309/mmedia. The distribution of cortical bone and spongiosa at the macroscopic dimensions of the phantom, as well as the distribution of trabecular bone and marrow tissues at the microscopic dimensions of the phantom, is imposed through detailed analyses of whole-body ex vivo CT images (1 mm resolution) and spongiosa-specific ex vivo microCT images (30 µm resolution), respectively, taken from a 40 year male cadaver. The method utilized in this work includes: (1) explicit accounting for changes in marrow self-dose with variations in marrow cellularity, (2) explicit accounting for electron escape from spongiosa, (3) explicit consideration of spongiosa cross-fire from cortical bone, and (4) explicit consideration of the ICRP's change in the surrogate tissue region defining the location of the osteoprogenitor cells (from a 10 µm endosteal layer covering the trabecular and cortical surfaces to a 50 µm shallow marrow layer covering trabecular and medullary cavity surfaces). Skeletal-averaged values of absorbed fraction in the present model are noted to be very compatible with those weighted by the skeletal tissue distributions found in the ICRP Publication 110 adult male and female voxel phantoms, but are in many cases incompatible with values used in current and widely implemented internal dosimetry software.

Business or pleasure? Utilitarian versus hedonic considerations in emotion regulation.

PubMed

Tamir, Maya; Chiu, Chi-Yue; Gross, James J

2007-08-01

It is widely accepted that emotions have utilitarian as well as hedonic consequences. Nevertheless, it is typically assumed that individuals regulate emotions to obtain hedonic, rather than utilitarian, benefits. In this study, the authors tested whether individuals represent the utility of pleasant and unpleasant emotions and whether they would be motivated to experience unpleasant emotions if they believed they could be useful. First, findings revealed that participants explicitly viewed approach emotions (e.g., excitement) as useful for obtaining rewards, but viewed avoidance emotions (e.g., worry) as useful for avoiding threats. Second, this pattern was replicated in implicit representations of emotional utility, which were dissociated from explicit ones. Third, implicit, but not explicit, representations of emotional utility predicted motives for emotion regulation. When anticipating a threatening task, participants who viewed emotions such as worry and fear as useful for avoiding threats preferred to engage in activities that were likely to increase worry and fear (vs. excitement) before the task. These findings demonstrate that utilitarian considerations play an important, if underappreciated, role in emotion regulation. ((c) 2007 APA, all rights reserved).

Should Countries Set an Explicit Health Benefits Package? The Case of the English National Health Service.

PubMed

Smith, Peter C; Chalkidou, Kalipso

2017-01-01

A fundamental debate in the transition towards universal health coverage concerns whether to establish an explicit health benefits package to which all citizens are entitled, and the level of detail in which to specify that package. At one extreme, the treatments to be funded, and the circumstances in which patients qualify for the treatment, might be specified in great detail, and be entirely mandatory. This would make clinicians little more than automata, carrying out prescribed practice. At the other extreme, priorities may be expressed in very broad terms, with no compulsion or other incentives to encourage adherence. The paper examines the arguments for and against setting an explicit benefits package, and discusses the circumstances in which increased detail in specification are most appropriate. The English National Health Service is used as a case study, based on institutional history, official documents and research literature. Although the English NHS does not explicitly specify a health benefits package, it is in some respects establishing an 'intelligent' package, based on instruments such as an essential medicines list, clinical guidelines, provider payment and performance reporting, which acknowledges gaps in evidence and variations in local resource constraints. Further moves towards a more explicit specification are likely to yield substantial benefits in most health systems. Considerations in determining the 'hardness' of benefits package specification might include the quality of information about the costs and benefits of treatments, the heterogeneity of patient needs and preferences, the financing regime in place, and the nature of supply side constraints. Copyright © 2016 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

A Global Mitigation Hierarchy for Nature Conservation

PubMed Central

Bull, Joseph W; Addison, Prue F E; Burgass, Michael J; Gianuca, Dimas; Gorham, Taylor M; Jacob, Céline; Watson, James E M; Wilcox, Chris; Milner-Gulland, E J

2018-01-01

Abstract Efforts to conserve biodiversity comprise a patchwork of international goals, national-level plans, and local interventions that, overall, are failing. We discuss the potential utility of applying the mitigation hierarchy, widely used during economic development activities, to all negative human impacts on biodiversity. Evaluating all biodiversity losses and gains through the mitigation hierarchy could help prioritize consideration of conservation goals and drive the empirical evaluation of conservation investments through the explicit consideration of counterfactual trends and ecosystem dynamics across scales. We explore the challenges in using this framework to achieve global conservation goals, including operationalization and monitoring and compliance, and we discuss solutions and research priorities. The mitigation hierarchy's conceptual power and ability to clarify thinking could provide the step change needed to integrate the multiple elements of conservation goals and interventions in order to achieve successful biodiversity outcomes. PMID:29731513

Knowledge translation within a population health study: how do you do it?

PubMed Central

2013-01-01

Background Despite the considerable and growing body of knowledge translation (KT) literature, there are few methodologies sufficiently detailed to guide an integrated KT research approach for a population health study. This paper argues for a clearly articulated collaborative KT approach to be embedded within the research design from the outset. Discussion Population health studies are complex in their own right, and strategies to engage the local community in adopting new interventions are often fraught with considerable challenges. In order to maximise the impact of population health research, more explicit KT strategies need to be developed from the outset. We present four propositions, arising from our work in developing a KT framework for a population health study. These cover the need for an explicit theory-informed conceptual framework; formalizing collaborative approaches within the design; making explicit the roles of both the stakeholders and the researchers; and clarifying what counts as evidence. From our deliberations on these propositions, our own co-creating (co-KT) Framework emerged in which KT is defined as both a theoretical and practical framework for actioning the intent of researchers and communities to co-create, refine, implement and evaluate the impact of new knowledge that is sensitive to the context (values, norms and tacit knowledge) where it is generated and used. The co-KT Framework has five steps. These include initial contact and framing the issue; refining and testing knowledge; interpreting, contextualising and adapting knowledge to the local context; implementing and evaluating; and finally, the embedding and translating of new knowledge into practice. Summary Although descriptions of how to incorporate KT into research designs are increasing, current theoretical and operational frameworks do not generally span a holistic process from knowledge co-creation to knowledge application and implementation within one project. Population health studies may have greater health impact when KT is incorporated early and explicitly into the research design. This, we argue, will require that particular attention be paid to collaborative approaches, stakeholder identification and engagement, the nature and sources of evidence used, and the role of the research team working with the local study community. PMID:23694753

Explicit accounting of electronic effects on the Hugoniot of porous materials

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

Nayak, Bishnupriya; Menon, S. V. G., E-mail: menon.svg98@gmail.com

2016-03-28

A generalized enthalpy based equation of state, which includes thermal electron excitations explicitly, is formulated from simple considerations. Its application to obtain Hugoniot of materials needs simultaneous evaluation of pressure-volume curve and temperature, the latter requiring solution of a differential equation. The errors involved in two recent papers [Huayun et al., J. Appl. Phys. 92, 5917 (2002); 92, 5924 (2002)], which employed this approach, are brought out and discussed. In addition to developing the correct set of equations, the present work also provides a numerical method to implement this approach. Constant pressure specific heat of ions and electrons and ionicmore » enthalpy parameter, needed for applications, are calculated using a three component equation of state. The method is applied to porous Cu with different initial porosities. Comparison of results with experimental data shows good agreement. It is found that temperatures along the Hugoniot of porous materials are significantly modified due to electronic effects.« less

Explicit solutions of a gravity-induced film flow along a convectively heated vertical wall.

PubMed

Raees, Ammarah; Xu, Hang

2013-01-01

The gravity-driven film flow has been analyzed along a vertical wall subjected to a convective boundary condition. The Boussinesq approximation is applied to simplify the buoyancy term, and similarity transformations are used on the mathematical model of the problem under consideration, to obtain a set of coupled ordinary differential equations. Then the reduced equations are solved explicitly by using homotopy analysis method (HAM). The resulting solutions are investigated for heat transfer effects on velocity and temperature profiles.

GRADE equity guidelines 3: considering health equity in GRADE guideline development: rating the certainty of synthesized evidence.

PubMed

Welch, Vivian A; Akl, Elie A; Pottie, Kevin; Ansari, Mohammed T; Briel, Matthias; Christensen, Robin; Dans, Antonio; Dans, Leonila; Eslava-Schmalbach, Javier; Guyatt, Gordon; Hultcrantz, Monica; Jull, Janet; Katikireddi, Srinivasa Vittal; Lang, Eddy; Matovinovic, Elizabeth; Meerpohl, Joerg J; Morton, Rachael L; Mosdol, Annhild; Murad, M Hassan; Petkovic, Jennifer; Schünemann, Holger; Sharaf, Ravi; Shea, Bev; Singh, Jasvinder A; Solà, Ivan; Stanev, Roger; Stein, Airton; Thabaneii, Lehana; Tonia, Thomy; Tristan, Mario; Vitols, Sigurd; Watine, Joseph; Tugwell, Peter

2017-10-01

The aim of this paper is to describe a conceptual framework for how to consider health equity in the Grading Recommendations Assessment and Development Evidence (GRADE) guideline development process. Consensus-based guidance developed by the GRADE working group members and other methodologists. We developed consensus-based guidance to help address health equity when rating the certainty of synthesized evidence (i.e., quality of evidence). When health inequity is determined to be a concern by stakeholders, we propose five methods for explicitly assessing health equity: (1) include health equity as an outcome; (2) consider patient-important outcomes relevant to health equity; (3) assess differences in the relative effect size of the treatment; (4) assess differences in baseline risk and the differing impacts on absolute effects; and (5) assess indirectness of evidence to disadvantaged populations and/or settings. The most important priority for research on health inequity and guidelines is to identify and document examples where health equity has been considered explicitly in guidelines. Although there is a weak scientific evidence base for assessing health equity, this should not discourage the explicit consideration of how guidelines and recommendations affect the most vulnerable members of society. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Phases of higher spin black holes: Hawking-Page, transitions between black holes, and a critical point

NASA Astrophysics Data System (ADS)

Bañados, Máximo; Düring, Gustavo; Faraggi, Alberto; Reyes, Ignacio A.

2017-08-01

We study the thermodynamic phase diagram of three-dimensional s l (N ;R ) higher spin black holes. By analyzing the semiclassical partition function we uncover a rich structure that includes Hawking-Page transitions to the AdS3 vacuum, first order phase transitions among black hole states, and a second order critical point. Our analysis is explicit for N =4 but we extrapolate some of our conclusions to arbitrary N . In particular, we argue that even N is stable in the ensemble under consideration but odd N is not.

A Green's function formulation for a nonlinear potential flow solution applicable to transonic flow

NASA Technical Reports Server (NTRS)

Baker, A. J.; Fox, C. H., Jr.

1977-01-01

Routine determination of inviscid subsonic flow fields about wing-body-tail configurations employing a Green's function approach for numerical solution of the perturbation velocity potential equation is successfully extended into the high subsonic subcritical flow regime and into the shock-free supersonic flow regime. A modified Green's function formulation, valid throughout a range of Mach numbers including transonic, that takes an explicit accounting of the intrinsic nonlinearity in the parent governing partial differential equations is developed. Some considerations pertinent to flow field predictions in the transonic flow regime are discussed.

Implicit and Explicit Representations of Hand Position in Tool Use

PubMed Central

Rand, Miya K.; Heuer, Herbert

2013-01-01

Understanding the interactions of visual and proprioceptive information in tool use is important as it is the basis for learning of the tool's kinematic transformation and thus skilled performance. This study investigated how the CNS combines seen cursor positions and felt hand positions under a visuo-motor rotation paradigm. Young and older adult participants performed aiming movements on a digitizer while looking at rotated visual feedback on a monitor. After each movement, they judged either the proprioceptively sensed hand direction or the visually sensed cursor direction. We identified asymmetric mutual biases with a strong visual dominance. Furthermore, we found a number of differences between explicit and implicit judgments of hand directions. The explicit judgments had considerably larger variability than the implicit judgments. The bias toward the cursor direction for the explicit judgments was about twice as strong as for the implicit judgments. The individual biases of explicit and implicit judgments were uncorrelated. Biases of these judgments exhibited opposite sequential effects. Moreover, age-related changes were also different between these judgments. The judgment variability was decreased and the bias toward the cursor direction was increased with increasing age only for the explicit judgments. These results indicate distinct explicit and implicit neural representations of hand direction, similar to the notion of distinct visual systems. PMID:23894307

Explicit and implicit assessment of gender roles.

PubMed

Fernández, Juan; Quiroga, M Ángeles; Escorial, Sergio; Privado, Jesús

2014-05-01

Gender roles have been assessed by explicit measures and, recently, by implicit measures. In the former case, the theoretical assumptions have been questioned by empirical results. To solve this contradiction, we carried out two concatenated studies based on a relatively well-founded theoretical and empirical approach. The first study was designed to obtain a sample of genderized activities of the domestic sphere by means of an explicit assessment. Forty-two raters (22 women and 20 men, balanced on age, sex, and level of education) took part as raters. In the second study, an implicit assessment of gender roles was carried out, focusing on the response time given to the sample activities obtained from the first study. A total of 164 adults (90 women and 74 men, mean age = 43), with experience in living with a partner and balanced on age, sex, and level of education, participated. Taken together, results show that explicit and implicit assessment converge. The current social reality shows that there is still no equity in some gender roles in the domestic sphere. These consistent results show considerable theoretical and empirical robustness, due to the double implicit and explicit assessment.

It's all connected: Pathways in visual object recognition and early noun learning.

PubMed

Smith, Linda B

2013-11-01

A developmental pathway may be defined as the route, or chain of events, through which a new structure or function forms. For many human behaviors, including object name learning and visual object recognition, these pathways are often complex and multicausal and include unexpected dependencies. This article presents three principles of development that suggest the value of a developmental psychology that explicitly seeks to trace these pathways and uses empirical evidence on developmental dependencies among motor development, action on objects, visual object recognition, and object name learning in 12- to 24-month-old infants to make the case. The article concludes with a consideration of the theoretical implications of this approach. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

Impact of mesophyll diffusion on estimated global land CO 2 fertilization

DOE PAGES

Sun, Ying; Gu, Lianhong; Dickinson, Robert E.; ...

2014-10-13

In C 3 plants, CO 2 concentrations drop considerably along mesophyll diffusion pathways from substomatal cavities to chloroplasts where CO 2 assimilation occurs. Global carbon cycle models have not explicitly represented this internal drawdown and so overestimate CO 2 available for carboxylation and underestimate photosynthetic responsiveness to atmospheric CO 2. An explicit consideration of mesophyll diffusion increases the modeled cumulative CO 2 fertilization effect (CFE) for global gross primary production (GPP) from 915 PgC to 1057 PgC for the period of 1901 to 2010. This increase represents a 16% correction, large enough to explain the persistent overestimation of growth ratesmore » of historical atmospheric CO 2 by Earth System Models. Without this correction, the CFE for global GPP is underestimated by 0.05 PgC yr -1ppm -1. This finding implies that the contemporary terrestrial biosphere is more CO 2-limited than previously thought.« less

The free energy landscape of small peptides as obtained from metadynamics with umbrella sampling corrections

PubMed Central

Babin, Volodymyr; Roland, Christopher; Darden, Thomas A.; Sagui, Celeste

2007-01-01

There is considerable interest in developing methodologies for the accurate evaluation of free energies, especially in the context of biomolecular simulations. Here, we report on a reexamination of the recently developed metadynamics method, which is explicitly designed to probe “rare events” and areas of phase space that are typically difficult to access with a molecular dynamics simulation. Specifically, we show that the accuracy of the free energy landscape calculated with the metadynamics method may be considerably improved when combined with umbrella sampling techniques. As test cases, we have studied the folding free energy landscape of two prototypical peptides: Ace-(Gly)2-Pro-(Gly)3-Nme in vacuo and trialanine solvated by both implicit and explicit water. The method has been implemented in the classical biomolecular code AMBER and is to be distributed in the next scheduled release of the code. © 2006 American Institute of Physics. PMID:17144742

Trait-based assessment of borderline personality disorder using the NEO Five-Factor Inventory: Phenotypic and genetic support

PubMed Central

Few, Lauren R.; Miller, Joshua D.; Grant, Julia D.; Maples, Jessica; Trull, Timothy J.; Nelson, Elliot C.; Oltmanns, Thomas F.; Martin, Nicholas G.; Lynskey, Michael T.; Agrawal, Arpana

2015-01-01

The aim of the current study was to examine the reliability and validity of a trait-based assessment of borderline personality disorder (BPD) using the NEO Five-Factor Inventory. Correlations between the Five-Factor Inventory-BPD composite (FFI-BPD) and explicit measures of BPD were examined across six samples, including undergraduate, community, and clinical samples. The median correlation was .60, which was nearly identical to the correlation between measures of BPD and a BPD composite generated from the full Revised NEO Personality Inventory (i.e., NEO-BPD; r =.61). Correlations between FFI-BPD and relevant measures of psychiatric symptomatology and etiology (e.g., childhood abuse, drug use, depression, and personality disorders) were also examined and compared to those generated using explicit measures of BPD and NEO-BPD. As expected, the FFI-BPD composite correlated most strongly with measures associated with high levels of Neuroticism, such as depression, anxiety, and emotion dysregulation, and the pattern of correlations generated using the FFI-BPD was highly similar to those generated using explicit measures of BPD and NEO-BPD. Finally, genetic analyses estimated that FFI-BPD is 44% heritable, which is comparable to meta-analytic research examining genetics associated with BPD, and revealed that 71% of the genetic influences are shared between FFI-BPD and a self-report measure assessing BPD (Personality Assessment Inventory – Borderline subscale; Morey, 1991). Generally, these results support the use of FFI-BPD as a reasonable proxy for BPD, which has considerable implications, particularly for potential gene-finding efforts in large, epidemiological datasets that include the NEO FFI. PMID:25984635

Commentary: considerations for using the 'Trials within Cohorts' design in a clinical trial of an investigational medicinal product.

PubMed

Bibby, Anna C; Torgerson, David J; Leach, Samantha; Lewis-White, Helen; Maskell, Nick A

2018-01-08

The 'trials within cohorts' (TwiC) design is a pragmatic approach to randomised trials in which trial participants are randomly selected from an existing cohort. The design has multiple potential benefits, including the option of conducting multiple trials within the same cohort. To date, the TwiC design methodology been used in numerous clinical settings but has never been applied to a clinical trial of an investigational medicinal product (CTIMP). We have recently secured the necessary approvals to undertake the first CTIMP using the TwiC design. In this paper, we describe some of the considerations and modifications required to ensure such a trial is compliant with Good Clinical Practice and international clinical trials regulations. We advocate using a two-stage consent process and using the consent stages to explicitly differentiate between trial participants and cohort participants who are providing control data. This distinction ensured compliance but had consequences with respect to costings, recruitment and the trial assessment schedule. We have demonstrated that it is possible to secure ethical and regulatory approval for a CTIMP TwiC. By including certain considerations at the trial design stage, we believe this pragmatic and efficient methodology could be utilised in other CTIMPs in future.

A comparison of two central difference schemes for solving the Navier-Stokes equations

NASA Technical Reports Server (NTRS)

Maksymiuk, C. M.; Swanson, R. C.; Pulliam, T. H.

1990-01-01

Five viscous transonic airfoil cases were computed by two significantly different computational fluid dynamics codes: An explicit finite-volume algorithm with multigrid, and an implicit finite-difference approximate-factorization method with Eigenvector diagonalization. Both methods are described in detail, and their performance on the test cases is compared. The codes utilized the same grids, turbulence model, and computer to provide the truest test of the algorithms. The two approaches produce very similar results, which, for attached flows, also agree well with experimental results; however, the explicit code is considerably faster.

Age effects on explicit and implicit memory

PubMed Central

Ward, Emma V.; Berry, Christopher J.; Shanks, David R.

2013-01-01

It is well-documented that explicit memory (e.g., recognition) declines with age. In contrast, many argue that implicit memory (e.g., priming) is preserved in healthy aging. For example, priming on tasks such as perceptual identification is often not statistically different in groups of young and older adults. Such observations are commonly taken as evidence for distinct explicit and implicit learning/memory systems. In this article we discuss several lines of evidence that challenge this view. We describe how patterns of differential age-related decline may arise from differences in the ways in which the two forms of memory are commonly measured, and review recent research suggesting that under improved measurement methods, implicit memory is not age-invariant. Formal computational models are of considerable utility in revealing the nature of underlying systems. We report the results of applying single and multiple-systems models to data on age effects in implicit and explicit memory. Model comparison clearly favors the single-system view. Implications for the memory systems debate are discussed. PMID:24065942

Planning Faculty Reduction.

ERIC Educational Resources Information Center

Rose, Homer C., Jr.; Hample, Stephen R.

1982-01-01

Considerations that can help colleges and universities develop institutionally specific strategies for planning faculty reductions are addressed. It is suggested that an institution can provide a fair and workable reduction plan if it: thoroughly explores alternatives to faculty layoffs; develops explicit standards and procedures for reduction…

Simulating ectomycorrhiza in boreal forests: implementing ectomycorrhizal fungi model MYCOFON in CoupModel (v5)

NASA Astrophysics Data System (ADS)

He, Hongxing; Meyer, Astrid; Jansson, Per-Erik; Svensson, Magnus; Rütting, Tobias; Klemedtsson, Leif

2018-02-01

The symbiosis between plants and Ectomycorrhizal fungi (ECM) is shown to considerably influence the carbon (C) and nitrogen (N) fluxes between the soil, rhizosphere, and plants in boreal forest ecosystems. However, ECM are either neglected or presented as an implicit, undynamic term in most ecosystem models, which can potentially reduce the predictive power of models.

In order to investigate the necessity of an explicit consideration of ECM in ecosystem models, we implement the previously developed MYCOFON model into a detailed process-based, soil-plant-atmosphere model, Coup-MYCOFON, which explicitly describes the C and N fluxes between ECM and roots. This new Coup-MYCOFON model approach (ECM explicit) is compared with two simpler model approaches: one containing ECM implicitly as a dynamic uptake of organic N considering the plant roots to represent the ECM (ECM implicit), and the other a static N approach in which plant growth is limited to a fixed N level (nonlim). Parameter uncertainties are quantified using Bayesian calibration in which the model outputs are constrained to current forest growth and soil C / N ratio for four forest sites along a climate and N deposition gradient in Sweden and simulated over a 100-year period.

The nonlim approach could not describe the soil C / N ratio due to large overestimation of soil N sequestration but simulate the forest growth reasonably well. The ECM implicit and explicit approaches both describe the soil C / N ratio well but slightly underestimate the forest growth. The implicit approach simulated lower litter production and soil respiration than the explicit approach. The ECM explicit Coup-MYCOFON model provides a more detailed description of internal ecosystem fluxes and feedbacks of C and N between plants, soil, and ECM. Our modeling highlights the need to incorporate ECM and organic N uptake into ecosystem models, and the nonlim approach is not recommended for future long-term soil C and N predictions. We also provide a key set of posterior fungal parameters that can be further investigated and evaluated in future ECM studies.

Developing interventions for chronically ill patients: is coping a helpful concept?

PubMed

de Ridder, D; Schreurs, K

2001-03-01

In this review, the role of coping in the development of psychosocial interventions for chronically ill patients is discussed. After summarizing the theoretical issues involved in the translation of the coping concept into an intervention, a review is undertaken of 35 studies concerned with the impact of interventions aimed at improving coping on patients' quality of life. These studies concern seven different chronic disease types (AIDS, asthma, cancer, cardiovascular diseases, chronic pain, diabetes, and rheumatoid arthritis) and show explicit consideration of attempts to manage illness in terms of coping to be rare. Many studies nevertheless address the equivalent of coping, namely behaviors and/or cognitions intended to deal with an illness situation appraised as stressful. The results of these studies are encouraging, although largely limited to the improvement of one or two particular coping strategies and problem-focused strategies in particular. It is argued that in order to expand on these initially positive findings, greater and more explicit consideration should be given to the potential of the coping concept for intervention with the chronically ill. The appraisal of stressful situations, the use of coping resources, and the strategic application of particular coping strategies should, for example, be given more careful consideration.

'Governance of' and 'Governance by': implementing a clinical governance framework in an area mental health service.

PubMed

O'Connor, Nick; Paton, Michael

2008-04-01

A framework developed to promote the understanding and application of clinical governance principles in an area mental health service is described. The framework is operationalized through systems, processes, roles and responsibilities. The development of an explicit and operationalizable framework for clinical governance arose from the authors' experiences in leading and managing mental health services. There is a particular emphasis on improvement of quality of care and patient safety. The framework is informed by recent developments in thinking about clinical governance, including key documents from Australia and the United Kingdom. The operational nature of the framework allows for key components of clinical governance to be described explicitly, communicated effectively, and continually tested and improved. Further consideration and assessment of the value of differing approaches to this task are required. For example, a general, illustrative approach to raise clinician awareness can be contrasted with prescriptive and specified approaches which progressively encompass the many functions and processes of a mental health service. Mental health clinicians and managers can be guided by a framework that will ensure safe, high quality and continually improving processes of care.

More than a feeling: Pervasive influences of memory without awareness of retrieval

PubMed Central

Voss, Joel L.; Lucas, Heather D.; Paller, Ken A.

2015-01-01

The subjective experiences of recollection and familiarity have featured prominently in the search for neurocognitive mechanisms of memory. However, these two explicit expressions of memory, which involve conscious awareness of memory retrieval, are distinct from an entire category of implicit expressions of memory that do not entail such awareness. This review summarizes recent evidence showing that neurocognitive processing related to implicit memory can powerfully influence the behavioral and neural measures typically associated with explicit memory. Although there are striking distinctions between the neurocognitive processing responsible for implicit versus explicit memory, tests designed to measure only explicit memory nonetheless often capture implicit memory processing as well. In particular, the evidence described here suggests that investigations of familiarity memory are prone to the accidental capture of implicit memory processing. These findings have considerable implications for neurocognitive accounts of memory, as they suggest that many neural and behavioral measures often accepted as signals of explicit memory instead reflect the distinct operation of implicit memory mechanisms that are only sometimes related to explicit memory expressions. Proper identification of the explicit and implicit mechanisms for memory is vital to understanding the normal operation of memory, in addition to the disrupted memory capabilities associated with many neurological disorders and mental illnesses. We suggest that future progress requires utilizing neural, behavioral, and subjective evidence to dissociate implicit and explicit memory processing so as to better understand their distinct mechanisms as well as their potential relationships. When searching for the neurocognitive mechanisms of memory, it is important to keep in mind that memory involves more than a feeling. PMID:24171735

Dissociation between implicit and explicit responses in postconditioning UCS revaluation after fear conditioning in humans

PubMed Central

Schultz, Douglas H.; Balderston, Nicholas L.; Geiger, Jennifer A.; Helmstetter, Fred J.

2014-01-01

The nature of the relationship between explicit and implicit learning is a topic of considerable debate. In order to investigate this relationship we conducted two experiments on postconditioning revaluation of the unconditional stimulus (UCS) in human fear conditioning. In Experiment 1, the intensity of the UCS was decreased following acquisition for one group (devaluation) and held constant for another group (control). A subsequent test revealed that even though both groups exhibited similar levels of UCS expectancy, the devaluation group had significantly smaller conditional skin conductance responses. The devaluation effect was not explained by differences in the explicit estimates of UCS probability or explicit knowledge that the UCS intensity had changed. In Experiment 2, the value of the UCS was increased following acquisition for one group (inflation) and held constant for another group (control). Test performance revealed that UCS inflation did not alter expectancy ratings, but the inflation group exhibited larger learned skin conductance responses than the control group. The inflation effect was not explained by differences in the explicit estimates of UCS probability or explicit knowledge that the UCS intensity had changed. The SCR revaluation effect was not dependent on explicit memory processes in either experiment. In both experiments we found differences on an implicit measure of learning in the absence of changes in explicit measures. Together, the differences observed between expectancy measures and skin conductance support the idea that these responses might reflect different types of memory formed during the same training procedure and be supported by separate neural systems. PMID:23731073

Improving Land-Surface Model Hydrology: Is an Explicit Aquifer Model Better than a Deeper Soil Profile?

NASA Technical Reports Server (NTRS)

Gulden, L. E.; Rosero, E.; Yang, Z.-L.; Rodell, Matthew; Jackson, C. S.; Niu, G.-Y.; Yeh, P. J.-F.; Famiglietti, J. S.

2007-01-01

Land surface models (LSMs) are computer programs, similar to weather and climate prediction models, which simulate the storage and movement of water (including soil moisture, snow, evaporation, and runoff) after it falls to the ground as precipitation. It is not currently possible to measure all of the variables of interest everywhere on Earth with sufficient accuracy. Hence LSMs have been developed to integrate the available information, including satellite observations, using powerful computers, in order to track water storage and redistribution. The maps are used to improve weather forecasts, support water resources and agricultural applications, and study the Earth's water cycle and climate variability. Recently, the models have begun to simulate groundwater storage. In this paper, we compare several possible approaches, and examine the pitfalls associated with trying to estimate aquifer parameters (such as porosity) that are required by the models. We find that explicit representation of groundwater, as opposed to the addition of deeper soil layers, considerably decreases the sensitivity of modeled terrestrial water storage to aquifer parameter choices. We also show that approximate knowledge of parameter values is not sufficient to guarantee realistic model performance: because interaction among parameters is significant, they must be prescribed as a harmonious set.

A methodological approach for deriving regional crop rotations as basis for the assessment of the impact of agricultural strategies using soil erosion as example.

PubMed

Lorenz, Marco; Fürst, Christine; Thiel, Enrico

2013-09-01

Regarding increasing pressures by global societal and climate change, the assessment of the impact of land use and land management practices on land degradation and the related decrease in sustainable provision of ecosystem services gains increasing interest. Existing approaches to assess agricultural practices focus on the assessment of single crops or statistical data because spatially explicit information on practically applied crop rotations is mostly not available. This provokes considerable uncertainties in crop production models as regional specifics have to be neglected or cannot be considered in an appropriate way. In a case study in Saxony, we developed an approach to (i) derive representative regional crop rotations by combining different data sources and expert knowledge. This includes the integration of innovative crop sequences related to bio-energy production or organic farming and different soil tillage, soil management and soil protection techniques. Furthermore, (ii) we developed a regionalization approach for transferring crop rotations and related soil management strategies on the basis of statistical data and spatially explicit data taken from so called field blocks. These field blocks are the smallest spatial entity for which agricultural practices must be reported to apply for agricultural funding within the frame of the European Agricultural Fund for Rural Development (EAFRD) program. The information was finally integrated into the spatial decision support tool GISCAME to assess and visualize in spatially explicit manner the impact of alternative agricultural land use strategies on soil erosion risk and ecosystem services provision. Objective of this paper is to present the approach how to create spatially explicit information on agricultural management practices for a study area around Dresden, the capital of the German Federal State Saxony. Copyright © 2013 Elsevier Ltd. All rights reserved.

Management considerations

Treesearch

Steven T. Knick; Steven E. Hanser; Matthias Leu; Cameron L. Aldridge; Scott E. Neilsen; Mary M. Rowland; Sean P. Finn; Michael J. Wisdom

2011-01-01

We conducted an ecoregional assessment of sagebrush (Artemisia spp.) ecosystems in the Wyoming Basins and surrounding regions (WBEA) to determine broad-scale species-environmental relationships. Our goal was to assess the potential influence from threats to the sagebrush ecosystem on associated wildlife through the use of spatially explicit...

Default contagion risks in Russian interbank market

NASA Astrophysics Data System (ADS)

Leonidov, A. V.; Rumyantsev, E. L.

2016-06-01

Systemic risks of default contagion in the Russian interbank market are investigated. The analysis is based on considering the bow-tie structure of the weighted oriented graph describing the structure of the interbank loans. A probabilistic model of interbank contagion explicitly taking into account the empirical bow-tie structure reflecting functionality of the corresponding nodes (borrowers, lenders, borrowers and lenders simultaneously), degree distributions and disassortativity of the interbank network under consideration based on empirical data is developed. The characteristics of contagion-related systemic risk calculated with this model are shown to be in agreement with those of explicit stress tests.

GRADE equity guidelines 1: considering health equity in GRADE guideline development: introduction and rationale.

PubMed

Welch, Vivian A; Akl, Elie A; Guyatt, Gordon; Pottie, Kevin; Eslava-Schmalbach, Javier; Ansari, Mohammed T; de Beer, Hans; Briel, Matthias; Dans, Tony; Dans, Inday; Hultcrantz, Monica; Jull, Janet; Katikireddi, Srinivasa Vittal; Meerpohl, Joerg; Morton, Rachael; Mosdol, Annhild; Petkovic, Jennifer; Schünemann, Holger J; Sharaf, Ravi N; Singh, Jasvinder A; Stanev, Roger; Tonia, Thomy; Tristan, Mario; Vitols, Sigurd; Watine, Joseph; Tugwell, Peter

2017-10-01

This article introduces the rationale and methods for explicitly considering health equity in the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology for development of clinical, public health, and health system guidelines. We searched for guideline methodology articles, conceptual articles about health equity, and examples of guidelines that considered health equity explicitly. We held three meetings with GRADE Working Group members and invited comments from the GRADE Working Group listserve. We developed three articles on incorporating equity considerations into the overall approach to guideline development, rating certainty, and assembling the evidence base and evidence to decision and/or recommendation. Clinical and public health guidelines have a role to play in promoting health equity by explicitly considering equity in the process of guideline development. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Content relatedness in the social web based on social explicit semantic analysis

NASA Astrophysics Data System (ADS)

Ntalianis, Klimis; Otterbacher, Jahna; Mastorakis, Nikolaos

2017-06-01

In this paper a novel content relatedness algorithm for social media content is proposed, based on the Explicit Semantic Analysis (ESA) technique. The proposed scheme takes into consideration social interactions. In particular starting from the vector space representation model, similarity is expressed by a summation of term weight products. In this paper, term weights are estimated by a social computing method, where the strength of each term is calculated by the attention the terms receives. For this reason each post is split into two parts, title and comments area, while attention is defined by the number of social interactions such as likes and shares. The overall approach is named Social Explicit Semantic Analysis. Experimental results on real data show the advantages and limitations of the proposed approach, while an initial comparison between ESA and S-ESA is very promising.

An image-based skeletal dosimetry model for the ICRP reference newborn—internal electron sources

NASA Astrophysics Data System (ADS)

Pafundi, Deanna; Rajon, Didier; Jokisch, Derek; Lee, Choonsik; Bolch, Wesley

2010-04-01

In this study, a comprehensive electron dosimetry model of newborn skeletal tissues is presented. The model is constructed using the University of Florida newborn hybrid phantom of Lee et al (2007 Phys. Med. Biol. 52 3309-33), the newborn skeletal tissue model of Pafundi et al (2009 Phys. Med. Biol. 54 4497-531) and the EGSnrc-based Paired Image Radiation Transport code of Shah et al (2005 J. Nucl. Med. 46 344-53). Target tissues include the active bone marrow (surrogate tissue for hematopoietic stem cells), shallow marrow (surrogate tissue for osteoprogenitor cells) and unossified cartilage (surrogate tissue for chondrocytes). Monoenergetic electron emissions are considered over the energy range 1 keV to 10 MeV for the following source tissues: active marrow, trabecular bone (surfaces and volumes), cortical bone (surfaces and volumes) and cartilage. Transport results are reported as specific absorbed fractions according to the MIRD schema and are given as skeletal-averaged values in the paper with bone-specific values reported in both tabular and graphic format as electronic annexes (supplementary data). The method utilized in this work uniquely includes (1) explicit accounting for the finite size and shape of newborn ossification centers (spongiosa regions), (2) explicit accounting for active and shallow marrow dose from electron emissions in cortical bone as well as sites of unossified cartilage, (3) proper accounting of the distribution of trabecular and cortical volumes and surfaces in the newborn skeleton when considering mineral bone sources and (4) explicit consideration of the marrow cellularity changes for active marrow self-irradiation as applicable to radionuclide therapy of diseased marrow in the newborn child.

The ABCs of Student Engagement

ERIC Educational Resources Information Center

Parsons, Seth A.; Nuland, Leila Richey; Parsons, Allison Ward

2014-01-01

Student engagement is an important consideration for teachers and administrators because it is explicitly associated with achievement. What the authors call the ABC's of engagement they outline as: Affective engagement, Behavioral engagement, and Cognitive engagement. They also present "Three Things Every Teacher Needs to Know about…

Finite Element Analysis of the Maximum Stress at the Joints of the Transmission Tower

NASA Astrophysics Data System (ADS)

Itam, Zarina; Beddu, Salmia; Liyana Mohd Kamal, Nur; Bamashmos, Khaled H.

2016-03-01

Transmission towers are tall structures, usually a steel lattice tower, used to support an overhead power line. Usually, transmission towers are analyzed as frame-truss systems and the members are assumed to be pin-connected without explicitly considering the effects of joints on the tower behavior. In this research, an engineering example of joint will be analyzed with the consideration of the joint detailing to investigate how it will affect the tower analysis. A static analysis using STAAD Pro was conducted to indicate the joint with the maximum stress. This joint will then be explicitly analyzed in ANSYS using the Finite Element Method. Three approaches were used in the software which are the simple plate model, bonded contact with no bolts, and beam element bolts. Results from the joint analysis show that stress values increased with joint details consideration. This proves that joints and connections play an important role in the distribution of stress within the transmission tower.

Numerical modeling of field-assisted ion-exchanged channel waveguides by the explicit consideration of space-charge buildup.

PubMed

Mrozek, Piotr

2011-08-01

A numerical model explicitly considering the space-charge density evolved both under the mask and in the region of optical structure formation was used to predict the profiles of Ag concentration during field-assisted Ag(+)-Na(+) ion exchange channel waveguide fabrication. The influence of the unequal values of diffusion constants and mobilities of incoming and outgoing ions, the value of a correlation factor (Haven ratio), and particularly space-charge density induced during the ion exchange, on the resulting profiles of Ag concentration was analyzed and discussed. It was shown that the incorporation into the numerical model of a small quantity of highly mobile ions other than exclusively Ag(+) and Na(+) may considerably affect the range and shape of calculated Ag profiles in the multicomponent glass. The Poisson equation was used to predict the electric field spread evolution in the glass substrate. The results of the numerical analysis were verified by the experimental data of Ag concentration in a channel waveguide fabricated using a field-assisted process.

Utilization of multiple-criteria decision analysis (MCDA) to support healthcare decision-making FIFARMA, 2016

PubMed Central

Drake, Julia I.; de Hart, Juan Carlos Trujillo; Monleón, Clara; Toro, Walter; Valentim, Joice

2017-01-01

ABSTRACT Background and objectives:   MCDA is a decision-making tool with increasing use in the healthcare sector, including HTA (Health Technology Assessment). By applying multiple criteria, including innovation, in a comprehensive, structured and explicit manner, MCDA fosters a transparent, participative, consistent decision-making process taking into consideration values of all stakeholders. This paper by FIFARMA (Latin American Federation of Pharmaceutical Industry) proposes the deliberative (partial) MCDA as a more pragmatic, agile approach, especially when newly implemented. Methods: Literature review including real-world examples of effective MCDA implementation in healthcare decision making in both the public and private sector worldwide and in LA. Results and conclusion: It is the view of FIFARMA that MCDA should strongly be considered as a tool to support HTA and broader healthcare decision making such as the contracts and tenders process in order to foster transparency, fairness, and collaboration amongst stakeholders. PMID:29081919

Spatially explicit multi-criteria decision analysis for managing vector-borne diseases

PubMed Central

2011-01-01

The complex epidemiology of vector-borne diseases creates significant challenges in the design and delivery of prevention and control strategies, especially in light of rapid social and environmental changes. Spatial models for predicting disease risk based on environmental factors such as climate and landscape have been developed for a number of important vector-borne diseases. The resulting risk maps have proven value for highlighting areas for targeting public health programs. However, these methods generally only offer technical information on the spatial distribution of disease risk itself, which may be incomplete for making decisions in a complex situation. In prioritizing surveillance and intervention strategies, decision-makers often also need to consider spatially explicit information on other important dimensions, such as the regional specificity of public acceptance, population vulnerability, resource availability, intervention effectiveness, and land use. There is a need for a unified strategy for supporting public health decision making that integrates available data for assessing spatially explicit disease risk, with other criteria, to implement effective prevention and control strategies. Multi-criteria decision analysis (MCDA) is a decision support tool that allows for the consideration of diverse quantitative and qualitative criteria using both data-driven and qualitative indicators for evaluating alternative strategies with transparency and stakeholder participation. Here we propose a MCDA-based approach to the development of geospatial models and spatially explicit decision support tools for the management of vector-borne diseases. We describe the conceptual framework that MCDA offers as well as technical considerations, approaches to implementation and expected outcomes. We conclude that MCDA is a powerful tool that offers tremendous potential for use in public health decision-making in general and vector-borne disease management in particular. PMID:22206355

Review and Assessment of JPL's Thermal Margins

NASA Technical Reports Server (NTRS)

Siebes, G.; Kingery, C.; Farguson, C.; White, M.; Blakely, M.; Nunes, J.; Avila, A.; Man, K.; Hoffman, A.; Forgrave, J.

2012-01-01

JPL has captured its experience from over four decades of robotic space exploration into a set of design rules. These rules have gradually changed into explicit requirements and are now formally implemented and verified. Over an extended period of time, the initial understanding of intent and rationale for these rules has faded and rules are now frequently applied without further consideration. In the meantime, mission classes and their associated risk postures have evolved, coupled with resource constraints and growing design diversity, bringing into question the current "one size fits all" thermal margin approach. This paper offers a systematic review of the heat flow path from an electronic junction to the eventual heat rejection to space. This includes the identification of different regimes along this path and the associated requirements. The work resulted in a renewed understanding of the intent behind JPL requirements for hot thermal margins and a framework for relevant considerations, which in turn enables better decision making when a deviation to these requirements is considered.

Hedged Monte-Carlo: low variance derivative pricing with objective probabilities

NASA Astrophysics Data System (ADS)

Potters, Marc; Bouchaud, Jean-Philippe; Sestovic, Dragan

2001-01-01

We propose a new ‘hedged’ Monte-Carlo ( HMC) method to price financial derivatives, which allows to determine simultaneously the optimal hedge. The inclusion of the optimal hedging strategy allows one to reduce the financial risk associated with option trading, and for the very same reason reduces considerably the variance of our HMC scheme as compared to previous methods. The explicit accounting of the hedging cost naturally converts the objective probability into the ‘risk-neutral’ one. This allows a consistent use of purely historical time series to price derivatives and obtain their residual risk. The method can be used to price a large class of exotic options, including those with path dependent and early exercise features.

Quantitative force measurements using frequency modulation atomic force microscopy—theoretical foundations

NASA Astrophysics Data System (ADS)

Sader, John E.; Uchihashi, Takayuki; Higgins, Michael J.; Farrell, Alan; Nakayama, Yoshikazu; Jarvis, Suzanne P.

2005-03-01

Use of the atomic force microscope (AFM) in quantitative force measurements inherently requires a theoretical framework enabling conversion of the observed deflection properties of the cantilever to an interaction force. In this paper, the theoretical foundations of using frequency modulation atomic force microscopy (FM-AFM) in quantitative force measurements are examined and rigorously elucidated, with consideration being given to both 'conservative' and 'dissipative' interactions. This includes a detailed discussion of the underlying assumptions involved in such quantitative force measurements, the presentation of globally valid explicit formulae for evaluation of so-called 'conservative' and 'dissipative' forces, discussion of the origin of these forces, and analysis of the applicability of FM-AFM to quantitative force measurements in liquid.

Theoretical and practical considerations for the development of online international collaborative learning for dental hygiene students.

PubMed

Gussy, M G; Knevel, R J M; Sigurdson, V; Karlberg, G

2006-08-01

Globalization and concurrent development in computer and communication technology has increased interest in collaborative online teaching and learning for students in higher education institutions. Many institutions and teachers have introduced computer-supported programmes in areas including dental hygiene. The potential for the use of this technology is exciting; however, its introduction should be careful and considered. We suggest that educators wanting to introduce computer-supported programmes make explicit their pedagogical principles and then select technologies that support and exploit these principles. This paper describes this process as it was applied to the development of an international web-based collaborative learning programme for dental hygiene students.

Where Does the Irrigation Water Go? An Estimate of the Contribution of Irrigation to Precipitation Using MERRA

NASA Technical Reports Server (NTRS)

Wei, Jiangfeng; Dirmeyer, Paul A.; Wisser, Dominik; Bosilovich, Michael G.; Mocko, David M.

2013-01-01

Irrigation is an important human activity that may impact local and regional climate, but current climate model simulations and data assimilation systems generally do not explicitly include it. The European Centre for Medium-Range Weather Forecasts (ECMWF) Interim Re-Analysis (ERA-Interim) shows more irrigation signal in surface evapotranspiration (ET) than the Modern-Era Retrospective Analysis for Research and Applications (MERRA) because ERA-Interim adjusts soil moisture according to the observed surface temperature and humidity while MERRA has no explicit consideration of irrigation at the surface. But, when compared with the results from a hydrological model with detailed considerations of agriculture, the ET from both reanalyses show large deficiencies in capturing the impact of irrigation. Here, a back-trajectory method is used to estimate the contribution of irrigation to precipitation over local and surrounding regions, using MERRA with observation-based corrections and added irrigation-caused ET increase from the hydrological model. Results show substantial contributions of irrigation to precipitation over heavily irrigated regions in Asia, but the precipitation increase is much less than the ET increase over most areas, indicating that irrigation could lead to water deficits over these regions. For the same increase in ET, precipitation increases are larger over wetter areas where convection is more easily triggered, but the percentage increase in precipitation is similar for different areas. There are substantial regional differences in the patterns of irrigation impact, but, for all the studied regions, the highest percentage contribution to precipitation is over local land.

The Analytic Hierarchy Process and Participatory Decisionmaking

Treesearch

Daniel L. Schmoldt; Daniel L. Peterson; Robert L. Smith

1995-01-01

Managing natural resource lands requires social, as well as biophysical, considerations. Unfortunately, it is extremely difficult to accurately assess and quantify changing social preferences, and to aggregate conflicting opinions held by diverse social groups. The Analytic Hierarchy Process (AHP) provides a systematic, explicit, rigorous, and robust mechanism for...

Donor Behavior and Voluntary Support for Higher Education Institutions.

ERIC Educational Resources Information Center

Leslie, Larry L.; Ramey, Garey

Voluntary support of higher education in America is investigated through regression analysis of institutional characteristics at two points in time. The assumption of donor rationality together with explicit consideration of interorganizational relationships offers a coherent framework for the analysis of voluntary support by the major…

The History Major and Liberal Education

ERIC Educational Resources Information Center

Liberal Education, 2009

2009-01-01

All disciplines and fields have something important to contribute to liberal learning. History, however, provides something distinctive. This contribution can be enhanced by a more explicit understanding of the relationship between the history major and the broader goals and processes of liberal learning, and through consideration of that…

How environmental justice patterns are shaped by place: terrain and tree canopy in Cincinnati, Ohio, USA

EPA Science Inventory

Understanding the spatial distribution of environmental amenities requires consideration of social and biogeophysical factors, and how they interact to produce patterns of environmental justice or injustice. In this study, we explicitly account for terrain, a key local environmen...

Improving our legacy: Incorporation of adaptive management into state wildlife action plans

USGS Publications Warehouse

Fontaine, J.J.

2011-01-01

The loss of biodiversity is a mounting concern, but despite numerous attempts there are few large scale conservation efforts that have proven successful in reversing current declines. Given the challenge of biodiversity conservation, there is a need to develop strategic conservation plans that address species declines even with the inherent uncertainty in managing multiple species in complex environments. In 2002, the State Wildlife Grant program was initiated to fulfill this need, and while not explicitly outlined by Congress follows the fundamental premise of adaptive management, 'Learning by doing'. When action is necessary, but basic biological information and an understanding of appropriate management strategies are lacking, adaptive management enables managers to be proactive in spite of uncertainty. However, regardless of the strengths of adaptive management, the development of an effective adaptive management framework is challenging. In a review of 53 State Wildlife Action Plans, I found a keen awareness by planners that adaptive management was an effective method for addressing biodiversity conservation, but the development and incorporation of explicit adaptive management approaches within each plan remained elusive. Only ???25% of the plans included a framework for how adaptive management would be implemented at the project level within their state. There was, however, considerable support across plans for further development and implementation of adaptive management. By furthering the incorporation of adaptive management principles in conservation plans and explicitly outlining the decision making process, states will be poised to meet the pending challenges to biodiversity conservation. ?? 2010 .

Improving our legacy: incorporation of adaptive management into state wildlife action plans.

PubMed

Fontaine, Joseph J

2011-05-01

The loss of biodiversity is a mounting concern, but despite numerous attempts there are few large scale conservation efforts that have proven successful in reversing current declines. Given the challenge of biodiversity conservation, there is a need to develop strategic conservation plans that address species declines even with the inherent uncertainty in managing multiple species in complex environments. In 2002, the State Wildlife Grant program was initiated to fulfill this need, and while not explicitly outlined by Congress follows the fundamental premise of adaptive management, 'Learning by doing'. When action is necessary, but basic biological information and an understanding of appropriate management strategies are lacking, adaptive management enables managers to be proactive in spite of uncertainty. However, regardless of the strengths of adaptive management, the development of an effective adaptive management framework is challenging. In a review of 53 State Wildlife Action Plans, I found a keen awareness by planners that adaptive management was an effective method for addressing biodiversity conservation, but the development and incorporation of explicit adaptive management approaches within each plan remained elusive. Only ~25% of the plans included a framework for how adaptive management would be implemented at the project level within their state. There was, however, considerable support across plans for further development and implementation of adaptive management. By furthering the incorporation of adaptive management principles in conservation plans and explicitly outlining the decision making process, states will be poised to meet the pending challenges to biodiversity conservation. Published by Elsevier Ltd.

The explicit and implicit dance in psychoanalytic change.

PubMed

Fosshage, James L

2004-02-01

How the implicit/non-declarative and explicit/declarative cognitive domains interact is centrally important in the consideration of effecting change within the psychoanalytic arena. Stern et al. (1998) declare that long-lasting change occurs in the domain of implicit relational knowledge. In the view of this author, the implicit and explicit domains are intricately intertwined in an interactive dance within a psychoanalytic process. The author views that a spirit of inquiry (Lichtenberg, Lachmann & Fosshage 2002) serves as the foundation of the psychoanalytic process. Analyst and patient strive to explore, understand and communicate and, thereby, create a 'spirit' of interaction that contributes, through gradual incremental learning, to new implicit relational knowledge. This spirit, as part of the implicit relational interaction, is a cornerstone of the analytic relationship. The 'inquiry' more directly brings explicit/declarative processing to the foreground in the joint attempt to explore and understand. The spirit of inquiry in the psychoanalytic arena highlights both the autobiographical scenarios of the explicit memory system and the mental models of the implicit memory system as each contributes to a sense of self, other, and self with other. This process facilitates the extrication and suspension of the old models, so that new models based on current relational experience can be gradually integrated into both memory systems for lasting change.

A review of numerical techniques approaching microstructures of crystalline rocks

NASA Astrophysics Data System (ADS)

Zhang, Yahui; Wong, Louis Ngai Yuen

2018-06-01

The macro-mechanical behavior of crystalline rocks including strength, deformability and failure pattern are dominantly influenced by their grain-scale structures. Numerical technique is commonly used to assist understanding the complicated mechanisms from a microscopic perspective. Each numerical method has its respective strengths and limitations. This review paper elucidates how numerical techniques take geometrical aspects of the grain into consideration. Four categories of numerical methods are examined: particle-based methods, block-based methods, grain-based methods, and node-based methods. Focusing on the grain-scale characters, specific relevant issues including increasing complexity of micro-structure, deformation and breakage of model elements, fracturing and fragmentation process are described in more detail. Therefore, the intrinsic capabilities and limitations of different numerical approaches in terms of accounting for the micro-mechanics of crystalline rocks and their phenomenal mechanical behavior are explicitly presented.

Experiments with explicit filtering for LES using a finite-difference method

NASA Technical Reports Server (NTRS)

Lund, T. S.; Kaltenbach, H. J.

1995-01-01

The equations for large-eddy simulation (LES) are derived formally by applying a spatial filter to the Navier-Stokes equations. The filter width as well as the details of the filter shape are free parameters in LES, and these can be used both to control the effective resolution of the simulation and to establish the relative importance of different portions of the resolved spectrum. An analogous, but less well justified, approach to filtering is more or less universally used in conjunction with LES using finite-difference methods. In this approach, the finite support provided by the computational mesh as well as the wavenumber-dependent truncation errors associated with the finite-difference operators are assumed to define the filter operation. This approach has the advantage that it is also 'automatic' in the sense that no explicit filtering: operations need to be performed. While it is certainly convenient to avoid the explicit filtering operation, there are some practical considerations associated with finite-difference methods that favor the use of an explicit filter. Foremost among these considerations is the issue of truncation error. All finite-difference approximations have an associated truncation error that increases with increasing wavenumber. These errors can be quite severe for the smallest resolved scales, and these errors will interfere with the dynamics of the small eddies if no corrective action is taken. Years of experience at CTR with a second-order finite-difference scheme for high Reynolds number LES has repeatedly indicated that truncation errors must be minimized in order to obtain acceptable simulation results. While the potential advantages of explicit filtering are rather clear, there is a significant cost associated with its implementation. In particular, explicit filtering reduces the effective resolution of the simulation compared with that afforded by the mesh. The resolution requirements for LES are usually set by the need to capture most of the energy-containing eddies, and if explicit filtering is used, the mesh must be enlarged so that these motions are passed by the filter. Given the high cost of explicit filtering, the following interesting question arises. Since the mesh must be expanded in order to perform the explicit filter, might it be better to take advantage of the increased resolution and simply perform an unfiltered simulation on the larger mesh? The cost of the two approaches is roughly the same, but the philosophy is rather different. In the filtered simulation, resolution is sacrificed in order to minimize the various forms of numerical error. In the unfiltered simulation, the errors are left intact, but they are concentrated at very small scales that could be dynamically unimportant from a LES perspective. Very little is known about this tradeoff and the objective of this work is to study this relationship in high Reynolds number channel flow simulations using a second-order finite-difference method.

Putting an Ethical Lens on Learning Analytics

ERIC Educational Resources Information Center

West, Deborah; Huijser, Henk; Heath, David

2016-01-01

As learning analytics activity has increased, a variety of ethical implications and considerations have emerged, though a significant research gap remains in explicitly investigating the views of key stakeholders, such as academic staff. This paper draws on ethics-related findings from an Australian study featuring two surveys, one of…

The Explicit Siphon

ERIC Educational Resources Information Center

Binder, P.-M.; Richert, A.

2011-01-01

A series of papers have recently addressed the mechanism by which a siphon works. While all this started as an effort to clarify words--namely, dictionary definitions--the authors feel that words, along with the misguided use of physical concepts, are currently contributing to considerable confusion and casuistry on this subject. They wish to make…

Research on golden-winged warblers: recent progress and current needs

Treesearch

Henry M. Streby; Ronald W. Rohrbaugh; David A. Buehler; David E. Andersen; Rachel Vallender; David I. King; Tom Will

2016-01-01

Considerable advances have been made in knowledge about Golden-winged Warblers (Vermivora chrysoptera) in the past decade. Recent employment of molecular analysis, stable-isotope analysis, telemetry-based monitoring of survival and behavior, and spatially explicit modeling techniques have added to, and revised, an already broad base of published...

Influence of Familiar Features on Diagnosis: Instantiated Features in an Applied Setting

ERIC Educational Resources Information Center

Dore, Kelly L.; Brooks, Lee R.; Weaver, Bruce; Norman, Geoffrey R.

2012-01-01

Medical diagnosis can be viewed as a categorization task. There are two mechanisms whereby humans make categorical judgments: "analytical reasoning," based on explicit consideration of features and "nonanalytical reasoning," an unconscious holistic process of matching against prior exemplars. However, there is evidence that prior experience can…

Science Education Curriculum Development Principles in Taiwan: Connecting with Aboriginal Learning and Culture

ERIC Educational Resources Information Center

Huang, Tzu-Hua; Liu, Yuan-Chen

2017-01-01

This paper reflects thorough consideration of cultural perspectives in the establishment of science curriculum development principles in Taiwan. The authority explicitly states that education measures and activities of aboriginal peoples' ethnic group should be implemented consistently to incorporate their history, language, art, living customs,…

President's Education Aims Aired

ERIC Educational Resources Information Center

McNeil, Michele; Klein, Alyson

2009-01-01

By explicitly naming education as one of three top priority areas in his first joint congressional address and in his first federal budget proposal, President Barack Obama is putting considerable political weight--and even more money--behind the agenda he laid out during his campaign. Certain themes he struck in the February 24…

President's Education Aims Aired

ERIC Educational Resources Information Center

McNeil, Michele; Klein, Alyson

2009-01-01

By explicitly naming education as one of three top priority areas in his first joint congressional address and in his first federal budget proposal, President Barack Obama is putting considerable political weight--and even more money--behind the agenda he laid out during his campaign. Certain themes he struck in the Feb. 24…

Considering Fees in Psychodynamic Psychotherapy: Opportunities for Residents

ERIC Educational Resources Information Center

Newman, Stewart S.

2005-01-01

OBJECTIVE: The topic of money is ubiquitous to psychodynamic therapy work, yet often neglected in residency training programs. Residency allows a unique opportunity to address issues pertaining to money and their impact on therapy. METHOD: Through the experience of the author, the need for a more explicit and systematic consideration within…

Fast but fleeting: adaptive motor learning processes associated with aging and cognitive decline.

PubMed

Trewartha, Kevin M; Garcia, Angeles; Wolpert, Daniel M; Flanagan, J Randall

2014-10-01

Motor learning has been shown to depend on multiple interacting learning processes. For example, learning to adapt when moving grasped objects with novel dynamics involves a fast process that adapts and decays quickly-and that has been linked to explicit memory-and a slower process that adapts and decays more gradually. Each process is characterized by a learning rate that controls how strongly motor memory is updated based on experienced errors and a retention factor determining the movement-to-movement decay in motor memory. Here we examined whether fast and slow motor learning processes involved in learning novel dynamics differ between younger and older adults. In addition, we investigated how age-related decline in explicit memory performance influences learning and retention parameters. Although the groups adapted equally well, they did so with markedly different underlying processes. Whereas the groups had similar fast processes, they had different slow processes. Specifically, the older adults exhibited decreased retention in their slow process compared with younger adults. Within the older group, who exhibited considerable variation in explicit memory performance, we found that poor explicit memory was associated with reduced retention in the fast process, as well as the slow process. These findings suggest that explicit memory resources are a determining factor in impairments in the both the fast and slow processes for motor learning but that aging effects on the slow process are independent of explicit memory declines. Copyright © 2014 the authors 0270-6474/14/3413411-11$15.00/0.

Optimal routing of hazardous substances in time-varying, stochastic transportation networks

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

Woods, A.L.; Miller-Hooks, E.; Mahmassani, H.S.

This report is concerned with the selection of routes in a network along which to transport hazardous substances, taking into consideration several key factors pertaining to the cost of transport and the risk of population exposure in the event of an accident. Furthermore, the fact that travel time and the risk measures are not constant over time is explicitly recognized in the routing decisions. Existing approaches typically assume static conditions, possibly resulting in inefficient route selection and unnecessary risk exposure. The report described the application of recent advances in network analysis methodologies to the problem of routing hazardous substances. Severalmore » specific problem formulations are presented, reflecting different degrees of risk aversion on the part of the decision-maker, as well as different possible operational scenarios. All procedures explicitly consider travel times and travel costs (including risk measures) to be stochastic time-varying quantities. The procedures include both exact algorithms, which may require extensive computational effort in some situations, as well as more efficient heuristics that may not guarantee a Pareto-optimal solution. All procedures are systematically illustrated for an example application using the Texas highway network, for both normal and incident condition scenarios. The application illustrates the trade-offs between the information obtained in the solution and computational efficiency, and highlights the benefits of incorporating these procedures in a decision-support system for hazardous substance shipment routing decisions.« less

Separating sensitivity from exposure in assessing extinction risk from climate change.

PubMed

Dickinson, Maria G; Orme, C David L; Suttle, K Blake; Mace, Georgina M

2014-11-04

Predictive frameworks of climate change extinction risk generally focus on the magnitude of climate change a species is expected to experience and the potential for that species to track suitable climate. A species' risk of extinction from climate change will depend, in part, on the magnitude of climate change the species experiences, its exposure. However, exposure is only one component of risk. A species' risk of extinction will also depend on its intrinsic ability to tolerate changing climate, its sensitivity. We examine exposure and sensitivity individually for two example taxa, terrestrial amphibians and mammals. We examine how these factors are related among species and across regions and how explicit consideration of each component of risk may affect predictions of climate change impacts. We find that species' sensitivities to climate change are not congruent with their exposures. Many highly sensitive species face low exposure to climate change and many highly exposed species are relatively insensitive. Separating sensitivity from exposure reveals patterns in the causes and drivers of species' extinction risk that may not be evident solely from predictions of climate change. Our findings emphasise the importance of explicitly including sensitivity and exposure to climate change in assessments of species' extinction risk.

Explicit B-spline regularization in diffeomorphic image registration

PubMed Central

Tustison, Nicholas J.; Avants, Brian B.

2013-01-01

Diffeomorphic mappings are central to image registration due largely to their topological properties and success in providing biologically plausible solutions to deformation and morphological estimation problems. Popular diffeomorphic image registration algorithms include those characterized by time-varying and constant velocity fields, and symmetrical considerations. Prior information in the form of regularization is used to enforce transform plausibility taking the form of physics-based constraints or through some approximation thereof, e.g., Gaussian smoothing of the vector fields [a la Thirion's Demons (Thirion, 1998)]. In the context of the original Demons' framework, the so-called directly manipulated free-form deformation (DMFFD) (Tustison et al., 2009) can be viewed as a smoothing alternative in which explicit regularization is achieved through fast B-spline approximation. This characterization can be used to provide B-spline “flavored” diffeomorphic image registration solutions with several advantages. Implementation is open source and available through the Insight Toolkit and our Advanced Normalization Tools (ANTs) repository. A thorough comparative evaluation with the well-known SyN algorithm (Avants et al., 2008), implemented within the same framework, and its B-spline analog is performed using open labeled brain data and open source evaluation tools. PMID:24409140

Stellar feedback strongly alters the amplification and morphology of galactic magnetic fields

NASA Astrophysics Data System (ADS)

Su, Kung-Yi; Hayward, Christopher C.; Hopkins, Philip F.; Quataert, Eliot; Faucher-Giguère, Claude-André; Kereš, Dušan

2018-01-01

Using high-resolution magnetohydrodynamic simulations of idealized, non-cosmological galaxies, we investigate how cooling, star formation and stellar feedback affect galactic magnetic fields. We find that the amplification histories, saturation values and morphologies of the magnetic fields vary considerably depending on the baryonic physics employed, primarily because of differences in the gas density distribution. In particular, adiabatic runs and runs with a subgrid (effective equation of state) stellar feedback model yield lower saturation values and morphologies that exhibit greater large-scale order compared with runs that adopt explicit stellar feedback and runs with cooling and star formation but no feedback. The discrepancies mostly lie in gas denser than the galactic average, which requires cooling and explicit fragmentation to capture. Independent of the baryonic physics included, the magnetic field strength scales with gas density as B ∝ n2/3, suggesting isotropic flux freezing or equipartition between the magnetic and gravitational energies during the field amplification. We conclude that accurate treatments of cooling, star formation and stellar feedback are crucial for obtaining the correct magnetic field strength and morphology in dense gas, which, in turn, is essential for properly modelling other physical processes that depend on the magnetic field, such as cosmic ray feedback.

Separating sensitivity from exposure in assessing extinction risk from climate change

PubMed Central

Dickinson, Maria G.; Orme, C. David L.; Suttle, K. Blake; Mace, Georgina M.

2014-01-01

Predictive frameworks of climate change extinction risk generally focus on the magnitude of climate change a species is expected to experience and the potential for that species to track suitable climate. A species' risk of extinction from climate change will depend, in part, on the magnitude of climate change the species experiences, its exposure. However, exposure is only one component of risk. A species' risk of extinction will also depend on its intrinsic ability to tolerate changing climate, its sensitivity. We examine exposure and sensitivity individually for two example taxa, terrestrial amphibians and mammals. We examine how these factors are related among species and across regions and how explicit consideration of each component of risk may affect predictions of climate change impacts. We find that species' sensitivities to climate change are not congruent with their exposures. Many highly sensitive species face low exposure to climate change and many highly exposed species are relatively insensitive. Separating sensitivity from exposure reveals patterns in the causes and drivers of species' extinction risk that may not be evident solely from predictions of climate change. Our findings emphasise the importance of explicitly including sensitivity and exposure to climate change in assessments of species' extinction risk. PMID:25367429

Systematic review of model-based analyses reporting the cost-effectiveness and cost-utility of cardiovascular disease management programs.

PubMed

Maru, Shoko; Byrnes, Joshua; Whitty, Jennifer A; Carrington, Melinda J; Stewart, Simon; Scuffham, Paul A

2015-02-01

The reported cost effectiveness of cardiovascular disease management programs (CVD-MPs) is highly variable, potentially leading to different funding decisions. This systematic review evaluates published modeled analyses to compare study methods and quality. Articles were included if an incremental cost-effectiveness ratio (ICER) or cost-utility ratio (ICUR) was reported, it is a multi-component intervention designed to manage or prevent a cardiovascular disease condition, and it addressed all domains specified in the American Heart Association Taxonomy for Disease Management. Nine articles (reporting 10 clinical outcomes) were included. Eight cost-utility and two cost-effectiveness analyses targeted hypertension (n=4), coronary heart disease (n=2), coronary heart disease plus stoke (n=1), heart failure (n=2) and hyperlipidemia (n=1). Study perspectives included the healthcare system (n=5), societal and fund holders (n=1), a third party payer (n=3), or was not explicitly stated (n=1). All analyses were modeled based on interventions of one to two years' duration. Time horizon ranged from two years (n=1), 10 years (n=1) and lifetime (n=8). Model structures included Markov model (n=8), 'decision analytic models' (n=1), or was not explicitly stated (n=1). Considerable variation was observed in clinical and economic assumptions and reporting practices. Of all ICERs/ICURs reported, including those of subgroups (n=16), four were above a US$50,000 acceptability threshold, six were below and six were dominant. The majority of CVD-MPs was reported to have favorable economic outcomes, but 25% were at unacceptably high cost for the outcomes. Use of standardized reporting tools should increase transparency and inform what drives the cost-effectiveness of CVD-MPs. © The European Society of Cardiology 2014.

Development of a framework for the assessment of capacity and throughput technologies within the National Airspace System

NASA Astrophysics Data System (ADS)

Garcia, Elena

The demand for air travel is expanding beyond the capacity of the existing National Airspace System. Excess traffic results in delays and compromised safety. Thus, a number of initiatives to improve airspace capacity have been proposed. To assess the impact of these technologies on air traffic one must move beyond the vehicle to a system-of-systems point of view. This top-level perspective must include consideration of the aircraft, airports, air traffic control and airlines that make up the airspace system. In addition to these components and their interactions economics, safety and government regulations must also be considered. Furthermore, the air transportation system is inherently variable with changes in everything from fuel prices to the weather. The development of a modeling environment that enables a comprehensive probabilistic evaluation of technological impacts was the subject of this thesis. The final modeling environment developed used economics as the thread to tie the airspace components together. Airport capacities and delays were calculated explicitly with due consideration to the impacts of air traffic control. The delay costs were then calculated for an entire fleet, and an airline economic analysis, considering the impact of these costs, was carried out. Airline return on investment was considered the metric of choice since it brings together all costs and revenues, including the cost of delays, landing fees for airport use and aircraft financing costs. Safety was found to require a level of detail unsuitable for a system-of-systems approach and was relegated to future airspace studies. Environmental concerns were considered to be incorporated into airport regulations and procedures and were not explicitly modeled. A deterministic case study was developed to test this modeling environment. The Atlanta airport operations for the year 2000 were used for validation purposes. A 2005 baseline was used as a basis for comparing the four technologies considered: a very large aircraft, Terminal Area Productivity air traffic control technologies, smoothing of an airline schedule, and the addition of a runway. A case including all four technologies simultaneously was also considered. Unfortunately, the complexity of the system prevented full exploration of the probabilistic aspects of the National Airspace System.

The Purpose of Analytical Models from the Perspective of a Data Provider.

ERIC Educational Resources Information Center

Sheehan, Bernard S.

The purpose of analytical models is to reduce complex institutional management problems and situations to simpler proportions and compressed time frames so that human skills of decision makers can be brought to bear most effectively. Also, modeling cultivates the art of management by forcing explicit and analytical consideration of important…

Perspectives on Complexity, Its Definition and Applications in the Field

ERIC Educational Resources Information Center

Koopmans, Matthijs

2017-01-01

There is considerable variation in the dynamical literature in how the term "complexity" is used. While there have been several attempts to describe from an educational perspective what complexity encompasses, the term is frequently used without an explicit definition. To forge a shared understanding of what complexity means, the purpose…

Research-Based Worksheets on Using Multiple Representations in Science Classrooms

ERIC Educational Resources Information Center

Hill, Matthew; Sharma, Manjula

2015-01-01

The ability to represent the world like a scientist is difficult to teach; it is more than simply knowing the representations (e.g., graphs, words, equations and diagrams). For meaningful science learning to take place, consideration needs to be given to explicitly integrating representations into instructional methods, linked to the content, and…

Child Labour, Education Policy and Governance in Cambodia

ERIC Educational Resources Information Center

Kim, Chae-Young

2011-01-01

This paper considers how the issue of child labour is located in Cambodian education policy debates and how it is affected by the major constraints surrounding the Cambodian education sector. In particular, it asks why Cambodian policy makers have not sought to address the issue explicitly despite its considerable, and adverse, impact on…

Reading Comprehension Instruction in Irish Primary Classrooms: Key Insights into Teachers' Perspectives on Classroom Practices

ERIC Educational Resources Information Center

Concannon-Gibney, Tara; Murphy, Brian

2012-01-01

Despite a wealth of international research indicating the importance but also the dearth of explicit reading comprehension instruction in classrooms, current classroom reading pedagogy does not appear to have acknowledged and addressed this shortcoming to any significant degree. This is cause for some considerable concern, as today's students…

Toward Modeling the Learner's Personality Using Educational Games

ERIC Educational Resources Information Center

Essalmi, Fathi; Tlili, Ahmed; Ben Ayed, Leila Jemni; Jemmi, Mohamed

2017-01-01

Learner modeling is a crucial step in the learning personalization process. It allows taking into consideration the learner's profile to make the learning process more efficient. Most studies refer to an explicit method, namely questionnaire, to model learners. Questionnaires are time consuming and may not be motivating for learners. Thus, this…

Family Poicy in Canada: Some Theoretical Considerations and a Practical Application.

ERIC Educational Resources Information Center

Hepworth, H. Philip

Frequently implicit in Canadian social policy addressing other issues, family policy is generally assumed to be a good thing, is bound up with social structure, and, when made explicit, is prescriptive and potentially embarrassing to government. Historically important as a forerunner of more recent income assistance programs, the provision of…

Clinical Studies of Biofield Therapies: Summary, Methodological Challenges, and Recommendations

PubMed Central

Hammerschlag, Richard; Mills, Paul; Cohen, Lorenzo; Krieger, Richard; Vieten, Cassandra; Lutgendorf, Susan

2015-01-01

Biofield therapies are noninvasive therapies in which the practitioner explicitly works with a client's biofield (interacting fields of energy and information that surround living systems) to stimulate healing responses in patients. While the practice of biofield therapies has existed in Eastern and Western cultures for thousands of years, empirical research on the effectiveness of biofield therapies is still relatively nascent. In this article, we provide a summary of the state of the evidence for biofield therapies for a number of different clinical conditions. We note specific methodological issues for research in biofield therapies that need to be addressed (including practitioner-based, outcomes-based, and research design considerations), as well as provide a list of suggested next steps for biofield researchers to consider. PMID:26665043

Clinical Studies of Biofield Therapies: Summary, Methodological Challenges, and Recommendations.

PubMed

Jain, Shamini; Hammerschlag, Richard; Mills, Paul; Cohen, Lorenzo; Krieger, Richard; Vieten, Cassandra; Lutgendorf, Susan

2015-11-01

Biofield therapies are noninvasive therapies in which the practitioner explicitly works with a client's biofield (interacting fields of energy and information that surround living systems) to stimulate healing responses in patients. While the practice of biofield therapies has existed in Eastern and Western cultures for thousands of years, empirical research on the effectiveness of biofield therapies is still relatively nascent. In this article, we provide a summary of the state of the evidence for biofield therapies for a number of different clinical conditions. We note specific methodological issues for research in biofield therapies that need to be addressed (including practitioner-based, outcomes-based, and research design considerations), as well as provide a list of suggested next steps for biofield researchers to consider.

The effect of articulatory suppression on implicit and explicit false memory in the DRM paradigm.

PubMed

Van Damme, Ilse; Menten, Jan; d'Ydewalle, Gery

2010-11-01

Several studies have shown that reliable implicit false memory can be obtained in the DRM paradigm. There has been considerable debate, however, about whether or not conscious activation of critical lures during study is a necessary condition for this. Recent findings have revealed that articulatory suppression prevents subsequent false priming in an anagram task (Lovden & Johansson, 2003). The present experiment sought to replicate and extend these findings to an implicit word stem completion task, and to additionally investigate the effect of articulatory suppression on explicit false memory. Results showed an inhibitory effect of articulatory suppression on veridical memory, as well as on implicit false memory, whereas the level of explicit false memory was heightened. This suggests that articulatory suppression did not merely eliminate conscious lure activation, but had a more general capacity-delimiting effect. The drop in veridical memory can be attributed to diminished encoding of item-specific information. Superficial encoding also limited the spreading of semantic activation during study, which inhibited later false priming. In addition, the lack of item-specific and phenomenological details caused impaired source monitoring at test, resulting in heightened explicit false memory.

Gravity discharge vessel revisited: An explicit Lambert W function solution

NASA Astrophysics Data System (ADS)

Digilov, Rafael M.

2017-07-01

Based on the generalized Poiseuille equation modified by a kinetic energy correction, an explicit solution for the time evolution of a liquid column draining under gravity through an exit capillary tube is derived in terms of the Lambert W function. In contrast to the conventional exponential behavior, as implied by the Poiseuille law, a new analytical solution gives a full account for the volumetric flow rate of a fluid through a capillary of any length and improves the precision of viscosity determination. The theoretical consideration may be of interest to students as an example of how implicit equations in the field of physics can be solved analytically using the Lambert function.

Fostering Upper Secondary Students' Ability to Engage in Practices of Scientific Investigation: a Comparative Analysis of an Explicit and an Implicit Instructional Approach

NASA Astrophysics Data System (ADS)

Vorholzer, Andreas; von Aufschnaiter, Claudia; Boone, William J.

2018-02-01

Inquiry-based teaching is considered as contributing to content-related, procedural, and epistemic learning goals of science education. In this study, a quasi-experimental research design was utilized to investigate to what extent embedding inquiry activities in an explicit and an implicit instructional approach fosters students' ability to engage in three practices of scientific investigation (POSI): (1) formulating questions and hypotheses, (2) planning investigations, (3) analyzing and interpreting data. Both approaches were implemented in a classroom-based intervention conducted in a German upper secondary school (N = 222). Students' procedural knowledge of the three POSI was assessed with a paper-pencil test prior and post to the intervention, their content knowledge and dispositional factors (e.g., cognitive abilities) were gathered once. Results show that not only explicit but also implicit instruction fosters students' knowledge of POSI. While overall explicit instruction was found to be more effective, the findings indicate that the effectiveness depends considerably on the practice addressed. Moreover, findings suggest that both approaches were equally beneficial for all students regardless of their prior content knowledge and their prior procedural knowledge of POSI. Potential conditions for the success of explicit and implicit approaches as well as implications for instruction on POSI in science classrooms and for future research are discussed.

Late positive potential to explicit sexual images associated with the number of sexual intercourse partners

PubMed Central

Steele, Vaughn R.; Staley, Cameron; Sabatinelli, Dean

2015-01-01

Risky sexual behaviors typically occur when a person is sexually motivated by potent, sexual reward cues. Yet, individual differences in sensitivity to sexual cues have not been examined with respect to sexual risk behaviors. A greater responsiveness to sexual cues might provide greater motivation for a person to act sexually; a lower responsiveness to sexual cues might lead a person to seek more intense, novel, possibly risky, sexual acts. In this study, event-related potentials were recorded in 64 men and women while they viewed a series of emotional, including explicit sexual, photographs. The motivational salience of the sexual cues was varied by including more and less explicit sexual images. Indeed, the more explicit sexual stimuli resulted in enhanced late positive potentials (LPP) relative to the less explicit sexual images. Participants with fewer sexual intercourse partners in the last year had reduced LPP amplitude to the less explicit sexual images than the more explicit sexual images, whereas participants with more partners responded similarly to the more and less explicit sexual images. This pattern of results is consistent with a greater responsivity model. Those who engage in more sexual behaviors consistent with risk are also more responsive to less explicit sexual cues. PMID:24526189

Effects of explicit instruction on the acquisition of students' science inquiry skills in grades 5 and 6 of primary education

NASA Astrophysics Data System (ADS)

Kruit, P. M.; Oostdam, R. J.; van den Berg, E.; Schuitema, J. A.

2018-03-01

In most primary science classes, students are taught science inquiry skills by way of learning by doing. Research shows that explicit instruction may be more effective. The aim of this study was to investigate the effects of explicit instruction on the acquisition of inquiry skills. Participants included 705 Dutch fifth and sixth graders. Students in an explicit instruction condition received an eight-week intervention of explicit instruction on inquiry skills. In the lessons of the implicit condition, all aspects of explicit instruction were absent. Students in the baseline condition followed their regular science curriculum. In a quasi-experimental pre-test-post-test design, two paper-and-pencil tests and three performance assessments were used to examine the acquisition and transfer of inquiry skills. Additionally, questionnaires were used to measure metacognitive skills. The results of a multilevel analysis controlling for pre-tests, general cognitive ability, age, gender and grade level indicated that explicit instruction facilitates the acquisition of science inquiry skills. Specifically on the performance assessment with an unfamiliar topic, students in the explicit condition outperformed students of both the implicit and baseline condition. Therefore, this study provides a strong argument for including an explicit teaching method for developing inquiry skills in primary science education.

Seniors, risk and rehabilitation: broadening our thinking.

PubMed

Egan, Mary Y; Laliberte Rudman, Debbie; Ceci, Christine; Kessler, Dorothy; McGrath, Colleen; Gardner, Paula; King, Judy; Lanoix, Monique; Malhotra, Ravi

2017-06-01

Conceptualizations of risk in seniors' rehabilitation emphasize potential physical injury, functional independence and cost containment, shifting rehabilitation from other considerations essential to promoting a satisfying life. In a two-day multidisciplinary planning meeting we critically examined and discussed alternatives to dominant conceptualizations. Invitees reflected on conceptualizations of risk in stroke rehabilitation and low vision rehabilitation, identified and explored positive and negative implications and generated alternative perspectives to support rehabilitation approaches related to living a good life. Current risk conceptualizations help focus rehabilitation teamwork and make this work publically recognizable and valued. However, they also lead to practice that is depersonalized, decontextualized and restrictive. Further research and practice development initiatives should include the voices of clinicians and seniors to more adequately support meaningfully living, and foster safe spaces for seniors and clinicians to speak candidly, comprehensively and respectfully about risk. To ensure that seniors' rehabilitation targets a satisfying life as defined by seniors, increased focus on the environment and more explicit examination of how cost containment concerns are driving services is also necessary. This work reinforced current concerns about conceptualizations of risk in seniors' rehabilitation and generated ways forward that re-focus rehabilitation more on promoting a satisfying life. Implications for rehabilitation In seniors' rehabilitation, considerations of risk focus on physical injury, functional dependence and cost containment. Focus on provider-defined risk of physical injury limits examination of patient goals and patients' histories of judging and dealing with risk. Focus on functional dependence and cost containment may lead to practice that is depersonalized and decontextualized. Abandonment of ableist and ageist thinking and an explicit focus on person-centered definitions of risk and a satisfying life are recommended.

Conflicting and complementary ethics of animal welfare considerations in reintroductions.

PubMed

Harrington, Lauren A; Moehrenschlager, Axel; Gelling, Merryl; Atkinson, Rob P D; Hughes, Joelene; Macdonald, David W

2013-06-01

Despite differences in focus, goals, and strategies between conservation biology and animal welfare, both are inextricably linked in many ways, and greater consideration of animal welfare, although important in its own right, also has considerable potential to contribute to conservation success. Nevertheless, animal welfare and animal ethics are not always considered explicitly within conservation practice. We systematically reviewed the recent scientific peer-reviewed and online gray literature on reintroductions of captive-bred and wild-caught animals (mammals, birds, amphibians, and reptiles) to quantify the occurrence of animal welfare issues. We considered monitoring that could be indicative of the animal's welfare status and supportive management actions that could improve animal welfare (regardless of whether the aim was explicitly animal-welfare orientated). Potential welfare issues (of variable nature and extent) were recorded in 67% of 199 projects reviewed; the most common were mortality >50%, dispersal or loss of animals, disease, and human conflict. Most (>70%) projects monitored survival, 18% assessed body condition, and 2% monitored stress levels. Animal welfare, explicitly, was referred to in 6% of projects. Supportive actions, most commonly use of on-site prerelease pens and provision of supplemental food or water, were implemented in 79% of projects, although the extent and duration of support varied. Practitioners can address animal-welfare issues in reintroductions by considering the potential implications for individual animals at all stages of the release process using the decision tree presented. We urge practitioners to report potential animal-welfare issues, describe mitigation actions, and evaluate their efficacy to facilitate transparent evaluation of common moral dilemmas and to advance communal strategies for dealing with them. Currently, comparative mortality rates, health risks, postrelease stress, effectiveness of supportive measures, and behavior of individuals warrant further research to improve animal welfare in reintroductions and to increase success of such projects. © 2013 Society for Conservation Biology.

Explicit frequency equations of free vibration of a nonlocal Timoshenko beam with surface effects

NASA Astrophysics Data System (ADS)

Zhao, Hai-Sheng; Zhang, Yao; Lie, Seng-Tjhen

2018-02-01

Considerations of nonlocal elasticity and surface effects in micro- and nanoscale beams are both important for the accurate prediction of natural frequency. In this study, the governing equation of a nonlocal Timoshenko beam with surface effects is established by taking into account three types of boundary conditions: hinged-hinged, clamped-clamped and clamped-hinged ends. For a hinged-hinged beam, an exact and explicit natural frequency equation is obtained. However, for clamped-clamped and clamped-hinged beams, the solutions of corresponding frequency equations must be determined numerically due to their transcendental nature. Hence, the Fredholm integral equation approach coupled with a curve fitting method is employed to derive the approximate fundamental frequency equations, which can predict the frequency values with high accuracy. In short, explicit frequency equations of the Timoshenko beam for three types of boundary conditions are proposed to exhibit directly the dependence of the natural frequency on the nonlocal elasticity, surface elasticity, residual surface stress, shear deformation and rotatory inertia, avoiding the complicated numerical computation.

Testing the Use of Implicit Solvent in the Molecular Dynamics Modelling of DNA Flexibility

NASA Astrophysics Data System (ADS)

Mitchell, J.; Harris, S.

DNA flexibility controls packaging, looping and in some cases sequence specific protein binding. Molecular dynamics simulations carried out with a computationally efficient implicit solvent model are potentially a powerful tool for studying larger DNA molecules than can be currently simulated when water and counterions are represented explicitly. In this work we compare DNA flexibility at the base pair step level modelled using an implicit solvent model to that previously determined from explicit solvent simulations and database analysis. Although much of the sequence dependent behaviour is preserved in implicit solvent, the DNA is considerably more flexible when the approximate model is used. In addition we test the ability of the implicit solvent to model stress induced DNA disruptions by simulating a series of DNA minicircle topoisomers which vary in size and superhelical density. When compared with previously run explicit solvent simulations, we find that while the levels of DNA denaturation are similar using both computational methodologies, the specific structural form of the disruptions is different.

Comparison of three explicit multigrid methods for the Euler and Navier-Stokes equations

NASA Technical Reports Server (NTRS)

Chima, Rodrick V.; Turkel, Eli; Schaffer, Steve

1987-01-01

Three explicit multigrid methods, Ni's method, Jameson's finite-volume method, and a finite-difference method based on Brandt's work, are described and compared for two model problems. All three methods use an explicit multistage Runge-Kutta scheme on the fine grid, and this scheme is also described. Convergence histories for inviscid flow over a bump in a channel for the fine-grid scheme alone show that convergence rate is proportional to Courant number and that implicit residual smoothing can significantly accelerate the scheme. Ni's method was slightly slower than the implicitly-smoothed scheme alone. Brandt's and Jameson's methods are shown to be equivalent in form but differ in their node versus cell-centered implementations. They are about 8.5 times faster than Ni's method in terms of CPU time. Results for an oblique shock/boundary layer interaction problem verify the accuracy of the finite-difference code. All methods slowed considerably on the stretched viscous grid but Brandt's method was still 2.1 times faster than Ni's method.

[Nutrition or industry. Experiences with nutritional considerations in the agricultural policy].

PubMed

Botten, G

1991-06-30

The need to export health considerations to various sector policies is regarded as important in health promotion. Health is generally a highly appreciated benefit; thus many sectors seek to use health as an argument for their policy. This article describes the relation between nutrition and agricultural policy in Norway. In areas where nutrition and agriculture had mutual interests, health considerations were easily exported. However, when interests diverged the issue became more complicated. Much effort was focused upon achieving correct use of nutritional arguments. Before negotiating and weighing respective viewpoints it is essential to clarify each sector's standpoint and interest. Conflicts and negotiations are linked to strategies which seek explicitly to integrate health premisses into sectors outside the health services itself.

What Does It Take for an Infant to Learn How to Use a Tool by Observation?

PubMed Central

Fagard, Jacqueline; Rat-Fischer, Lauriane; Esseily, Rana; Somogyi, Eszter; O’Regan, J. K.

2016-01-01

Observational learning is probably one of the most powerful factors determining progress during child development. When learning a new skill, infants rely on their own exploration; but they also frequently benefit from an adult’s verbal support or from demonstration by an adult modeling the action. At what age and under what conditions does adult demonstration really help the infant to learn a novel behavior? In this review, we summarize recently published work we have conducted on the acquisition of tool use during the second year of life. In particular, we consider under what conditions and to what extent seeing a demonstration from an adult advances an infant’s understanding of how to use a tool to obtain an out-of-reach object. Our results show that classic demonstration starts being helpful at 18 months of age. When adults explicitly show their intention prior to demonstration, even 16-month-old infants learn from the demonstration. On the other hand, providing an explicit demonstration (“look at how I do it”) is not very useful before infants are ready to succeed by themselves anyway. In contrast, repeated observations of the required action in a social context, without explicit reference to this action, considerably advances the age of success and the usefulness of providing a demonstration. We also show that the effect of demonstration can be enhanced if the demonstration makes the baby laugh. Taken together, the results from this series of studies on observational learning of tool use in infants suggest, first, that when observing a demonstration, infants do not know what to pay attention to: demonstration must be accompanied by rich social cues to be effective; second, infants’ attention is inhibited rather than enhanced by an explicit demand of “look at what I do”; and finally a humorous situation considerably helps infants understand the demonstration. PMID:26973565

What Does It Take for an Infant to Learn How to Use a Tool by Observation?

PubMed

Fagard, Jacqueline; Rat-Fischer, Lauriane; Esseily, Rana; Somogyi, Eszter; O'Regan, J K

2016-01-01

Observational learning is probably one of the most powerful factors determining progress during child development. When learning a new skill, infants rely on their own exploration; but they also frequently benefit from an adult's verbal support or from demonstration by an adult modeling the action. At what age and under what conditions does adult demonstration really help the infant to learn a novel behavior? In this review, we summarize recently published work we have conducted on the acquisition of tool use during the second year of life. In particular, we consider under what conditions and to what extent seeing a demonstration from an adult advances an infant's understanding of how to use a tool to obtain an out-of-reach object. Our results show that classic demonstration starts being helpful at 18 months of age. When adults explicitly show their intention prior to demonstration, even 16-month-old infants learn from the demonstration. On the other hand, providing an explicit demonstration ("look at how I do it") is not very useful before infants are ready to succeed by themselves anyway. In contrast, repeated observations of the required action in a social context, without explicit reference to this action, considerably advances the age of success and the usefulness of providing a demonstration. We also show that the effect of demonstration can be enhanced if the demonstration makes the baby laugh. Taken together, the results from this series of studies on observational learning of tool use in infants suggest, first, that when observing a demonstration, infants do not know what to pay attention to: demonstration must be accompanied by rich social cues to be effective; second, infants' attention is inhibited rather than enhanced by an explicit demand of "look at what I do"; and finally a humorous situation considerably helps infants understand the demonstration.

Linking the concept of scale to studies of biological diversity: evolving approaches and tools.

USGS Publications Warehouse

Beever, E.A.; Swihart, R.K.; Bestelmeyer, B. T.

2006-01-01

Although the concepts of scale and biological diversity independently have received rapidly increasing attention in the scientific literature since the 1980s, the rate at which the two concepts have been investigated jointly has grown much more slowly. We find that scale considerations have been incorporated explicitly into six broad areas of investigation related to biological diversity: (1) heterogeneity within and among ecosystems, (2) disturbance ecology, (3) conservation and restoration, (4) invasion biology, (5) importance of temporal scale for understanding processes, and (6) species responses to environmental heterogeneity. In addition to placing the papers of this Special Feature within the context of brief summaries of the expanding literature on these six topics, we provide an overview of tools useful for integrating scale considerations into studies of biological diversity. Such tools include hierarchical and structural-equation modelling, kriging, variable-width buffers, k-fold cross-validation, and cascading graph diagrams, among others. Finally, we address some of the major challenges and research frontiers that remain, and conclude with a look to the future.

Toward a Physical Characterization of Raindrop Collision Outcome Regimes

NASA Technical Reports Server (NTRS)

Testik, F. Y.; Barros, Ana P.; Bilven, Francis L.

2011-01-01

A comprehensive raindrop collision outcome regime diagram that delineates the physical conditions associated with the outcome regimes (i.e., bounce, coalescence, and different breakup types) of binary raindrop collisions is proposed. The proposed diagram builds on a theoretical regime diagram defined in the phase space of collision Weber numbers We and the drop diameter ratio p by including critical angle of impact considerations. In this study, the theoretical regime diagram is first evaluated against a comprehensive dataset for drop collision experiments representative of raindrop collisions in nature. Subsequently, the theoretical regime diagram is modified to explicitly describe the dominant regimes of raindrop interactions in (We, p) by delineating the physical conditions necessary for the occurrence of distinct types of collision-induced breakup (neck/filament, sheet, disk, and crown breakups) based on critical angle of impact consideration. Crown breakup is a subtype of disk breakup for lower collision kinetic energy that presents distinctive morphology. Finally, the experimental results are analyzed in the context of the comprehensive collision regime diagram, and conditional probabilities that can be used in the parameterization of breakup kernels in stochastic models of raindrop dynamics are provided.

Finnish policy approach and measures for the promotion of sustainability in contaminated land management.

PubMed

Reinikainen, Jussi; Sorvari, Jaana; Tikkanen, Sarianne

2016-12-15

The importance of sustainability considerations in contaminated land management (CLM) is highlighted in policy frameworks all around the world. It means that while the reduction of risks to human health and the environment remains the main goal of CLM, a variety of other environmental factors as well as economic and social aspects have an increasing role in decision making. The success of finding the right balance between these considerations and incorporating them in the risk management approach defines the overall sustainability of the outcome. Although the concept and principles of sustainable CLM are already widely accepted, they have not been fully realized in national procedures. According to several studies this often results from the lack of explicit policy measures. A sound policy framework in conjunction with functional policy instruments is therefore a prerequisite for the attainment of sustainable practices. In Finland, the environmental administration along with other key stakeholder groups, including regional authorities, landowners, consultants, industries, research institutes and academia, has developed a national strategy and associated policy measures in order to promote sustainable CLM. Copyright © 2016 Elsevier Ltd. All rights reserved.

Setting conservation priorities.

PubMed

Wilson, Kerrie A; Carwardine, Josie; Possingham, Hugh P

2009-04-01

A generic framework for setting conservation priorities based on the principles of classic decision theory is provided. This framework encapsulates the key elements of any problem, including the objective, the constraints, and knowledge of the system. Within the context of this framework the broad array of approaches for setting conservation priorities are reviewed. While some approaches prioritize assets or locations for conservation investment, it is concluded here that prioritization is incomplete without consideration of the conservation actions required to conserve the assets at particular locations. The challenges associated with prioritizing investments through time in the face of threats (and also spatially and temporally heterogeneous costs) can be aided by proper problem definition. Using the authors' general framework for setting conservation priorities, multiple criteria can be rationally integrated and where, how, and when to invest conservation resources can be scheduled. Trade-offs are unavoidable in priority setting when there are multiple considerations, and budgets are almost always finite. The authors discuss how trade-offs, risks, uncertainty, feedbacks, and learning can be explicitly evaluated within their generic framework for setting conservation priorities. Finally, they suggest ways that current priority-setting approaches may be improved.

Practical Methods for Including Torsional Anharmonicity in Thermochemical Calculations on Complex Molecules: The Internal-Coordinate Multi-Structural Approximation

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

Zheng, J.; Yu, T.; Papajak, E.

2011-01-01

Many methods for correcting harmonic partition functions for the presence of torsional motions employ some form of one-dimensional torsional treatment to replace the harmonic contribution of a specific normal mode. However, torsions are often strongly coupled to other degrees of freedom, especially other torsions and low-frequency bending motions, and this coupling can make assigning torsions to specific normal modes problematic. Here, we present a new class of methods, called multi-structural (MS) methods, that circumvents the need for such assignments by instead adjusting the harmonic results by torsional correction factors that are determined using internal coordinates. We present three versions ofmore » the MS method: (i) MS-AS based on including all structures (AS), i.e., all conformers generated by internal rotations; (ii) MS-ASCB based on all structures augmented with explicit conformational barrier (CB) information, i.e., including explicit calculations of all barrier heights for internal-rotation barriers between the conformers; and (iii) MS-RS based on including all conformers generated from a reference structure (RS) by independent torsions. In the MS-AS scheme, one has two options for obtaining the local periodicity parameters, one based on consideration of the nearly separable limit and one based on strongly coupled torsions. The latter involves assigning the local periodicities on the basis of Voronoi volumes. The methods are illustrated with calculations for ethanol, 1-butanol, and 1-pentyl radical as well as two one-dimensional torsional potentials. The MS-AS method is particularly interesting because it does not require any information about conformational barriers or about the paths that connect the various structures.« less

Practical methods for including torsional anharmonicity in thermochemical calculations on complex molecules: the internal-coordinate multi-structural approximation.

PubMed

Zheng, Jingjing; Yu, Tao; Papajak, Ewa; Alecu, I M; Mielke, Steven L; Truhlar, Donald G

2011-06-21

Many methods for correcting harmonic partition functions for the presence of torsional motions employ some form of one-dimensional torsional treatment to replace the harmonic contribution of a specific normal mode. However, torsions are often strongly coupled to other degrees of freedom, especially other torsions and low-frequency bending motions, and this coupling can make assigning torsions to specific normal modes problematic. Here, we present a new class of methods, called multi-structural (MS) methods, that circumvents the need for such assignments by instead adjusting the harmonic results by torsional correction factors that are determined using internal coordinates. We present three versions of the MS method: (i) MS-AS based on including all structures (AS), i.e., all conformers generated by internal rotations; (ii) MS-ASCB based on all structures augmented with explicit conformational barrier (CB) information, i.e., including explicit calculations of all barrier heights for internal-rotation barriers between the conformers; and (iii) MS-RS based on including all conformers generated from a reference structure (RS) by independent torsions. In the MS-AS scheme, one has two options for obtaining the local periodicity parameters, one based on consideration of the nearly separable limit and one based on strongly coupled torsions. The latter involves assigning the local periodicities on the basis of Voronoi volumes. The methods are illustrated with calculations for ethanol, 1-butanol, and 1-pentyl radical as well as two one-dimensional torsional potentials. The MS-AS method is particularly interesting because it does not require any information about conformational barriers or about the paths that connect the various structures.

Qualitative Secondary Analysis: A Case Exemplar.

PubMed

Tate, Judith Ann; Happ, Mary Beth

Qualitative secondary analysis (QSA) is the use of qualitative data that was collected by someone else or was collected to answer a different research question. Secondary analysis of qualitative data provides an opportunity to maximize data utility, particularly with difficult-to-reach patient populations. However, qualitative secondary analysis methods require careful consideration and explicit description to best understand, contextualize, and evaluate the research results. In this article, we describe methodologic considerations using a case exemplar to illustrate challenges specific to qualitative secondary analysis and strategies to overcome them. Copyright © 2017 National Association of Pediatric Nurse Practitioners. Published by Elsevier Inc. All rights reserved.

Efficiency and flexibility using implicit methods within atmosphere dycores

NASA Astrophysics Data System (ADS)

Evans, K. J.; Archibald, R.; Norman, M. R.; Gardner, D. J.; Woodward, C. S.; Worley, P.; Taylor, M.

2016-12-01

A suite of explicit and implicit methods are evaluated for a range of configurations of the shallow water dynamical core within the spectral-element Community Atmosphere Model (CAM-SE) to explore their relative computational performance. The configurations are designed to explore the attributes of each method under different but relevant model usage scenarios including varied spectral order within an element, static regional refinement, and scaling to large problem sizes. The limitations and benefits of using explicit versus implicit, with different discretizations and parameters, are discussed in light of trade-offs such as MPI communication, memory, and inherent efficiency bottlenecks. For the regionally refined shallow water configurations, the implicit BDF2 method is about the same efficiency as an explicit Runge-Kutta method, without including a preconditioner. Performance of the implicit methods with the residual function executed on a GPU is also presented; there is speed up for the residual relative to a CPU, but overwhelming transfer costs motivate moving more of the solver to the device. Given the performance behavior of implicit methods within the shallow water dynamical core, the recommendation for future work using implicit solvers is conditional based on scale separation and the stiffness of the problem. The strong growth of linear iterations with increasing resolution or time step size is the main bottleneck to computational efficiency. Within the hydrostatic dynamical core, of CAM-SE, we present results utilizing approximate block factorization preconditioners implemented using the Trilinos library of solvers. They reduce the cost of linear system solves and improve parallel scalability. We provide a summary of the remaining efficiency considerations within the preconditioner and utilization of the GPU, as well as a discussion about the benefits of a time stepping method that provides converged and stable solutions for a much wider range of time step sizes. As more complex model components, for example new physics and aerosols, are connected in the model, having flexibility in the time stepping will enable more options for combining and resolving multiple scales of behavior.

Trait-based assessment of borderline personality disorder using the NEO Five-Factor Inventory: Phenotypic and genetic support.

PubMed

Few, Lauren R; Miller, Joshua D; Grant, Julia D; Maples, Jessica; Trull, Timothy J; Nelson, Elliot C; Oltmanns, Thomas F; Martin, Nicholas G; Lynskey, Michael T; Agrawal, Arpana

2016-01-01

[Correction Notice: An Erratum for this article was reported in Vol 28(1) of Psychological Assessment (see record 2015-54029-001). The FFI-BPD values for Sample 3 in Table 2 should read 1.42 (0.44), 0.83.] The aim of the current study was to examine the reliability and validity of a trait-based assessment of borderline personality disorder (BPD) using the NEO Five-Factor Inventory. Correlations between the Five-Factor Inventory-BPD composite (FFI-BPD) and explicit measures of BPD were examined across 6 samples, including undergraduate, community, and clinical samples. The median correlation was .60, which was nearly identical to the correlation between measures of BPD and a BPD composite generated from the full Revised NEO Personality Inventory (i.e., NEO-BPD; r = .61). Correlations between FFI-BPD and relevant measures of psychiatric symptomatology and etiology (e.g., childhood abuse, drug use, depression, and personality disorders) were also examined and compared to those generated using explicit measures of BPD and NEO-BPD. As expected, the FFI-BPD composite correlated most strongly with measures associated with high levels of Neuroticism, such as depression, anxiety, and emotion dysregulation, and the pattern of correlations generated using the FFI-BPD was highly similar to those generated using explicit measures of BPD and NEO-BPD. Finally, genetic analyses estimated that FFI-BPD is 44% heritable, which is comparable to meta-analytic research examining genetics associated with BPD, and revealed that 71% of the genetic influences are shared between FFI-BPD and a self-report measure assessing BPD (Personality Assessment Inventory-Borderline subscale; Morey, 1991). Generally, these results support the use of FFI-BPD as a reasonable proxy for BPD, which has considerable implications, particularly for potential gene-finding efforts in large, epidemiological datasets that include the NEO FFI. (c) 2016 APA, all rights reserved).

A systematic review of ecological attributes that confer resilience to climate change in environmental restoration

PubMed Central

Timpane-Padgham, Britta L.

2017-01-01

Ecological restoration is widely practiced as a means of rehabilitating ecosystems and habitats that have been degraded or impaired through human use or other causes. Restoration practices now are confronted by climate change, which has the potential to influence long-term restoration outcomes. Concepts and attributes from the resilience literature can help improve restoration and monitoring efforts under changing climate conditions. We systematically examined the published literature on ecological resilience to identify biological, chemical, and physical attributes that confer resilience to climate change. We identified 45 attributes explicitly related to climate change and classified them as individual- (9), population- (6), community- (7), ecosystem- (7), or process-level attributes (16). Individual studies defined resilience as resistance to change or recovery from disturbance, and only a few studies explicitly included both concepts in their definition of resilience. We found that individual and population attributes generally are suited to species- or habitat-specific restoration actions and applicable at the population scale. Community attributes are better suited to habitat-specific restoration at the site scale, or system-wide restoration at the ecosystem scale. Ecosystem and process attributes vary considerably in their type and applicability. We summarize these relationships in a decision support table and provide three example applications to illustrate how these classifications can be used to prioritize climate change resilience attributes for specific restoration actions. We suggest that (1) including resilience as an explicit planning objective could increase the success of restoration projects, (2) considering the ecological context and focal scale of a restoration action is essential in choosing appropriate resilience attributes, and (3) certain ecological attributes, such as diversity and connectivity, are more commonly considered to confer resilience because they apply to a wide variety of species and ecosystems. We propose that identifying sources of ecological resilience is a critical step in restoring ecosystems in a changing climate. PMID:28301560

A systematic review of ecological attributes that confer resilience to climate change in environmental restoration.

PubMed

Timpane-Padgham, Britta L; Beechie, Tim; Klinger, Terrie

2017-01-01

Ecological restoration is widely practiced as a means of rehabilitating ecosystems and habitats that have been degraded or impaired through human use or other causes. Restoration practices now are confronted by climate change, which has the potential to influence long-term restoration outcomes. Concepts and attributes from the resilience literature can help improve restoration and monitoring efforts under changing climate conditions. We systematically examined the published literature on ecological resilience to identify biological, chemical, and physical attributes that confer resilience to climate change. We identified 45 attributes explicitly related to climate change and classified them as individual- (9), population- (6), community- (7), ecosystem- (7), or process-level attributes (16). Individual studies defined resilience as resistance to change or recovery from disturbance, and only a few studies explicitly included both concepts in their definition of resilience. We found that individual and population attributes generally are suited to species- or habitat-specific restoration actions and applicable at the population scale. Community attributes are better suited to habitat-specific restoration at the site scale, or system-wide restoration at the ecosystem scale. Ecosystem and process attributes vary considerably in their type and applicability. We summarize these relationships in a decision support table and provide three example applications to illustrate how these classifications can be used to prioritize climate change resilience attributes for specific restoration actions. We suggest that (1) including resilience as an explicit planning objective could increase the success of restoration projects, (2) considering the ecological context and focal scale of a restoration action is essential in choosing appropriate resilience attributes, and (3) certain ecological attributes, such as diversity and connectivity, are more commonly considered to confer resilience because they apply to a wide variety of species and ecosystems. We propose that identifying sources of ecological resilience is a critical step in restoring ecosystems in a changing climate.

Color-Blind Leadership: A Critical Race Theory Analysis of the ISLLC and ELCC Standards

ERIC Educational Resources Information Center

Davis, Bradley W.; Gooden, Mark A.; Micheaux, Donna J.

2015-01-01

Purpose: Working from the driving research question--"is the explicit consideration of race present in the ISLLC and ELCC standards?"--this article explores the implications of a school leadership landscape reliant on a collection of color-blind leadership standards to guide the preparation and practice of school leaders. In doing so, we…

Developing a Pilot Program to Embed Service-Learning in the Curriculum of a Christian Liberal Arts College

ERIC Educational Resources Information Center

Frawley, Rebecca Glenn

2013-01-01

Since equipping students for service to God and others is either an implicit or explicit element of the mission statement of every Christ-centered college and university, academic officers at such institutions should give serious consideration to making service-learning one of their regular pedagogical strategies. This paper presents the…

Simulating the effects of the southern pine beetle on regional dynamics 60 years into the future

Treesearch

Jennifer K. Costanza; Jiri Hulcr; Frank H. Koch; Todd Earnhardt; Alexa J. McKerrow; Rob R. Dunn; Jaime A. Collazo

2012-01-01

We developed a spatially explicit model that simulated future southern pine beetle (Dendroctonus frontalis, SPB) dynamics and pine forest management for a real landscape over 60 years to inform regional forest management. The SPB has a considerable effect on forest dynamics in the Southeastern United States, especially in loblolly pine (...

University Social Responsibility and Brand Image of Private Universities in Bangkok

ERIC Educational Resources Information Center

Plungpongpan, Jirawan; Tiangsoongnern, Leela; Speece, Mark

2016-01-01

Purpose: The purpose of this paper is to examine the effects of university social responsibility (USR) on the brand image of private universities in Thailand. Brand image is important for entry into the consideration set as prospective students evaluate options for university study. USR activities may be implicit or explicit, i.e., actively…

Changes in Determining Gifted Eligibility for Underrepresented Students. Research Note. Volume 0802

ERIC Educational Resources Information Center

Froman, Terry

2008-01-01

There are a number of detailed requirements for gifted screening, referral and eligibility specified under State Board Rules and School Board Rules. In all of these areas, explicit mention is made of the Florida Comprehensive Assessment Test (FCAT) Norm Referenced Test (NRT) scores as being integral components. Due to budget considerations, the…

Scaling laws and complexity in fire regimes [Chapter 2

Treesearch

Donald McKenzie; Maureen Kennedy

2011-01-01

Use of scaling terminology and concepts in ecology evolved rapidly from rare occurrences in the early 1980s to a central idea by the early 1990s (Allen and Hoekstra 1992; Levin 1992; Peterson and Parker 1998). In landscape ecology, use of "scale" frequently connotes explicitly spatial considerations (Dungan et al. 2002), notably grain and extent. More...

Extracellular mass transport considerations for space flight research concerning suspended and adherent in vitro cell cultures

NASA Technical Reports Server (NTRS)

Klaus, David M.; Benoit, Michael R.; Nelson, Emily S.; Hammond, Timmothy G.

2004-01-01

Conducting biological research in space requires consideration be given to isolating appropriate control parameters. For in vitro cell cultures, numerous environmental factors can adversely affect data interpretation. A biological response attributed to microgravity can, in theory, be explicitly correlated to a specific lack of weight or gravity-driven motion occurring to, within or around a cell. Weight can be broken down to include the formation of hydrostatic gradients, structural load (stress) or physical deformation (strain). Gravitationally induced motion within or near individual cells in a fluid includes sedimentation (or buoyancy) of the cell and associated shear forces, displacement of cytoskeleton or organelles, and factors associated with intra- or extracellular mass transport. Finally, and of particular importance for cell culture experiments, the collective effects of gravity must be considered for the overall system consisting of the cells, their environment and the device in which they are contained. This does not, however, rule out other confounding variables such as launch acceleration, on orbit vibration, transient acceleration impulses or radiation, which can be isolated using onboard centrifuges or vibration isolation techniques. A framework is offered for characterizing specific cause-and-effect relationships for gravity-dependent responses as a function of the above parameters.

Use of programme theory to understand the differential effects of interventions across socio-economic groups in systematic reviews-a systematic methodology review.

PubMed

Maden, Michelle; Cunliffe, Alex; McMahon, Naoimh; Booth, Andrew; Carey, Gina Michelle; Paisley, Suzy; Dickson, Rumona; Gabbay, Mark

2017-12-29

Systematic review guidance recommends the use of programme theory to inform considerations of if and how healthcare interventions may work differently across socio-economic status (SES) groups. This study aimed to address the lack of detail on how reviewers operationalise this in practice. A methodological systematic review was undertaken to assess if, how and the extent to which systematic reviewers operationalise the guidance on the use of programme theory in considerations of socio-economic inequalities in health. Multiple databases were searched from January 2013 to May 2016. Studies were included if they were systematic reviews assessing the effectiveness of an intervention and included data on SES. Two reviewers independently screened all studies, undertook quality assessment and extracted data. A narrative approach to synthesis was adopted. A total of 37 systematic reviews were included, 10 of which were explicit in the use of terminology for 'programme theory'. Twenty-nine studies used programme theory to inform both their a priori assumptions and explain their review findings. Of these, 22 incorporated considerations of both what and how interventions do/do not work in SES groups to both predict and explain their review findings. Thirteen studies acknowledged 24 unique theoretical references to support their assumptions of what or how interventions may have different effects in SES groups. Most reviewers used supplementary evidence to support their considerations of differential effectiveness. The majority of authors outlined a programme theory in the "Introduction" and "Discussion" sections of the review to inform their assumptions or provide explanations of what or how interventions may result in differential effects within or across SES groups. About a third of reviews used programme theory to inform the review analysis and/or synthesis. Few authors used programme theory to inform their inclusion criteria, data extraction or quality assessment. Twenty-one studies tested their a priori programme theory. The use of programme theory to inform considerations of if, what and how interventions lead to differential effects on health in different SES groups in the systematic review process is not yet widely adopted, is used implicitly, is often fragmented and is not implemented in a systematic way.

SOCIO-ETHICAL ISSUES IN PERSONALIZED MEDICINE: A SYSTEMATIC REVIEW OF ENGLISH LANGUAGE HEALTH TECHNOLOGY ASSESSMENTS OF GENE EXPRESSION PROFILING TESTS FOR BREAST CANCER PROGNOSIS.

PubMed

Ali-Khan, Sarah E; Black, Lee; Palmour, Nicole; Hallett, Michael T; Avard, Denise

2015-01-01

There have been multiple calls for explicit integration of ethical, legal, and social issues (ELSI) in health technology assessment (HTA) and addressing ELSI has been highlighted as key in optimizing benefits in the Omics/Personalized Medicine field. This study examines HTAs of an early clinical example of Personalized Medicine (gene expression profile tests [GEP] for breast cancer prognosis) aiming to: (i) identify ELSI; (ii) assess whether ELSIs are implicitly or explicitly addressed; and (iii) report methodology used for ELSI integration. A systematic search for HTAs (January 2004 to September 2012), followed by descriptive and qualitative content analysis. Seventeen HTAs for GEP were retrieved. Only three (18%) explicitly presented ELSI, and only one reported methodology. However, all of the HTAs included implicit ELSI. Eight themes of implicit and explicit ELSI were identified. "Classical" ELSI including privacy, informed consent, and concerns about limited patient/clinician genetic literacy were always presented explicitly. Some ELSI, including the need to understand how individual patients' risk tolerances affect clinical decision-making after reception of GEP results, were presented both explicitly and implicitly in HTAs. Others, such as concern about evidentiary deficiencies for clinical utility of GEP tests, occurred only implicitly. Despite a wide variety of important ELSI raised, these were rarely explicitly addressed in HTAs. Explicit treatment would increase their accessibility to decision-makers, and may augment HTA efficiency maximizing their utility. This is particularly important where complex Personalized Medicine applications are rapidly expanding choices for patients, clinicians and healthcare systems.

Medical students' and residents' clinical and educational experiences with defensive medicine.

PubMed

O'Leary, Kevin J; Choi, Jennifer; Watson, Katie; Williams, Mark V

2012-02-01

To assess medical students' and residents' experiences with defensive medicine, which is any deviation from sound medical practice due to a perceived threat of liability through either assurance or avoidance behaviors. Assurance behaviors include providing additional services of minimal clinical value. Avoidance behaviors include withholding services that are, or avoiding patients who are, perceived as high risk. The authors conducted a cross-sectional survey of fourth-year medical students and third-year residents in 2010. Respondents rated how often malpractice liability concerns caused their teams to engage in four types of assurance and two types of avoidance behaviors using a four-point scale (never, rarely, sometimes, often). Respondents also rated how often their attending physicians explicitly recommended that liability concerns be taken into account when making clinical decisions. Overall, 126 of 194 medical students (65%) and 76 of 141 residents (54%) completed the survey. Of the responding medical students, 116 (92%) reported sometimes or often encountering at least one assurance practice, and 43 (34%) reported encountering at least one avoidance practice. Of the responding residents, 73 (96%) reported encountering at least one assurance practice, and 33 (43%) reported encountering at least one avoidance practice. Overall, 50 of 121 medical students (41%) and 36 of 68 residents (53%) reported that their attending physicians sometimes or often explicitly taught them to take liability into account when making clinical decisions. Medical trainees reported frequently encountering defensive medicine practices and often being taught to take malpractice liability into consideration during clinical decision making.

Analytical steady-state solutions for water-limited cropping systems using saline irrigation water

NASA Astrophysics Data System (ADS)

Skaggs, T. H.; Anderson, R. G.; Corwin, D. L.; Suarez, D. L.

2014-12-01

Due to the diminishing availability of good quality water for irrigation, it is increasingly important that irrigation and salinity management tools be able to target submaximal crop yields and support the use of marginal quality waters. In this work, we present a steady-state irrigated systems modeling framework that accounts for reduced plant water uptake due to root zone salinity. Two explicit, closed-form analytical solutions for the root zone solute concentration profile are obtained, corresponding to two alternative functional forms of the uptake reduction function. The solutions express a general relationship between irrigation water salinity, irrigation rate, crop salt tolerance, crop transpiration, and (using standard approximations) crop yield. Example applications are illustrated, including the calculation of irrigation requirements for obtaining targeted submaximal yields, and the generation of crop-water production functions for varying irrigation waters, irrigation rates, and crops. Model predictions are shown to be mostly consistent with existing models and available experimental data. Yet the new solutions possess advantages over available alternatives, including: (i) the solutions were derived from a complete physical-mathematical description of the system, rather than based on an ad hoc formulation; (ii) the analytical solutions are explicit and can be evaluated without iterative techniques; (iii) the solutions permit consideration of two common functional forms of salinity induced reductions in crop water uptake, rather than being tied to one particular representation; and (iv) the utilized modeling framework is compatible with leading transient-state numerical models.

Ethical Design of Intelligent Assistive Technologies for Dementia: A Descriptive Review.

PubMed

Ienca, Marcello; Wangmo, Tenzin; Jotterand, Fabrice; Kressig, Reto W; Elger, Bernice

2017-09-22

The use of Intelligent Assistive Technology (IAT) in dementia care opens the prospects of reducing the global burden of dementia and enabling novel opportunities to improve the lives of dementia patients. However, with current adoption rates being reportedly low, the potential of IATs might remain under-expressed as long as the reasons for suboptimal adoption remain unaddressed. Among these, ethical and social considerations are critical. This article reviews the spectrum of IATs for dementia and investigates the prevalence of ethical considerations in the design of current IATs. Our screening shows that a significant portion of current IATs is designed in the absence of explicit ethical considerations. These results suggest that the lack of ethical consideration might be a codeterminant of current structural limitations in the translation of IATs from designing labs to bedside. Based on these data, we call for a coordinated effort to proactively incorporate ethical considerations early in the design and development of new products.

Recent Advances in Understanding Particle Acceleration Processes in Solar Flares

NASA Astrophysics Data System (ADS)

Zharkova, V. V.; Arzner, K.; Benz, A. O.; Browning, P.; Dauphin, C.; Emslie, A. G.; Fletcher, L.; Kontar, E. P.; Mann, G.; Onofri, M.; Petrosian, V.; Turkmani, R.; Vilmer, N.; Vlahos, L.

2011-09-01

We review basic theoretical concepts in particle acceleration, with particular emphasis on processes likely to occur in regions of magnetic reconnection. Several new developments are discussed, including detailed studies of reconnection in three-dimensional magnetic field configurations (e.g., current sheets, collapsing traps, separatrix regions) and stochastic acceleration in a turbulent environment. Fluid, test-particle, and particle-in-cell approaches are used and results compared. While these studies show considerable promise in accounting for the various observational manifestations of solar flares, they are limited by a number of factors, mostly relating to available computational power. Not the least of these issues is the need to explicitly incorporate the electrodynamic feedback of the accelerated particles themselves on the environment in which they are accelerated. A brief prognosis for future advancement is offered.

Criticality and Connectivity in Macromolecular Charge Complexation

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

Qin, Jian; de Pablo, Juan J.

We examine the role of molecular connectivity and architecture on the complexation of ionic macromolecules (polyelectrolytes) of finite size. A unified framework is developed and applied to evaluate the electrostatic correlation free energy for point-like, rod-like, and coil-like molecules. That framework is generalized to molecules of variable fractal dimensions, including dendrimers. Analytical expressions for the free energy, correlation length, and osmotic pressure are derived, thereby enabling consideration of the effects of charge connectivity, fractal dimension, and backbone stiffness on the complexation behavior of a wide range of polyelectrolytes. Results are presented for regions in the immediate vicinity of the criticalmore » region and far from it. A transparent and explicit expression for the coexistence curve is derived in order to facilitate analysis of experimentally observed phase diagrams.« less

Casimir force in a Lorentz violating theory

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

Frank, Mariana; Turan, Ismail

2006-08-01

We study the effects of the minimal extension of the standard model including Lorentz violation on the Casimir force between two parallel conducting plates in the vacuum. We provide explicit solutions for the electromagnetic field using scalar field analogy, for both the cases in which the Lorentz violating terms come from the CPT-even or CPT-odd terms. We also calculate the effects of the Lorentz violating terms for a fermion field between two parallel conducting plates and analyze the modifications of the Casimir force due to the modifications of the Dirac equation. In all cases under consideration, the standard formulas formore » the Casimir force are modified by either multiplicative or additive correction factors, the latter case exhibiting different dependence on the distance between the plates.« less

The right to health under international law and its relevance to the United States.

PubMed

Yamin, Alicia Ely

2005-07-01

In recent years, there have been considerable developments in international law with respect to the normative definition of the right to health, which includes both health care and healthy conditions. These norms offer a framework that shifts the analysis of issues such as disparities in treatment from questions of quality of care to matters of social justice. Building on work in social epidemiology, a rights paradigm explicitly links health with laws, policies, and practices that sustain a functional democracy and focuses on accountability. In the United States, framing a well-documented problem such as health disparities as a "rights violation" attaches shame and blame to governmental neglect. Further, international law offers standards for evaluating governmental conduct as well as mechanisms for establishing some degree of accountability.

A behavioral window on the mind of the market: an application of the response time paradigm.

PubMed

Mast, Fred W; Zaltman, Gerald

2005-11-15

This article focuses on the role of implicit knowledge consumers have about particular brands, products or names. The major findings of several studies, conducted at the Mind of the Market Laboratory at Harvard Business School, are presented with specific emphasis on studies in which response time measurements were the core method. The results revealed that implicit measures provide a rich understanding of the meaning conveyed by a product or brand. Moreover, there is also considerable evidence that implicit measures may be better than traditional explicit measures as predictors of consumer behavior. We discuss the implications for the study of consumer behavior and the importance of combining several methods including neuroimaging, which has received recent attention by marketers, economists and social scientists.

Replication and robustness in developmental research.

PubMed

Duncan, Greg J; Engel, Mimi; Claessens, Amy; Dowsett, Chantelle J

2014-11-01

Replications and robustness checks are key elements of the scientific method and a staple in many disciplines. However, leading journals in developmental psychology rarely include explicit replications of prior research conducted by different investigators, and few require authors to establish in their articles or online appendices that their key results are robust across estimation methods, data sets, and demographic subgroups. This article makes the case for prioritizing both explicit replications and, especially, within-study robustness checks in developmental psychology. It provides evidence on variation in effect sizes in developmental studies and documents strikingly different replication and robustness-checking practices in a sample of journals in developmental psychology and a sister behavioral science-applied economics. Our goal is not to show that any one behavioral science has a monopoly on best practices, but rather to show how journals from a related discipline address vital concerns of replication and generalizability shared by all social and behavioral sciences. We provide recommendations for promoting graduate training in replication and robustness-checking methods and for editorial policies that encourage these practices. Although some of our recommendations may shift the form and substance of developmental research articles, we argue that they would generate considerable scientific benefits for the field. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

Molecular Dynamics based on a Generalized Born solvation model: application to protein folding

NASA Astrophysics Data System (ADS)

Onufriev, Alexey

2004-03-01

An accurate description of the aqueous environment is essential for realistic biomolecular simulations, but may become very expensive computationally. We have developed a version of the Generalized Born model suitable for describing large conformational changes in macromolecules. The model represents the solvent implicitly as continuum with the dielectric properties of water, and include charge screening effects of salt. The computational cost associated with the use of this model in Molecular Dynamics simulations is generally considerably smaller than the cost of representing water explicitly. Also, compared to traditional Molecular Dynamics simulations based on explicit water representation, conformational changes occur much faster in implicit solvation environment due to the absence of viscosity. The combined speed-up allow one to probe conformational changes that occur on much longer effective time-scales. We apply the model to folding of a 46-residue three helix bundle protein (residues 10-55 of protein A, PDB ID 1BDD). Starting from an unfolded structure at 450 K, the protein folds to the lowest energy state in 6 ns of simulation time, which takes about a day on a 16 processor SGI machine. The predicted structure differs from the native one by 2.4 A (backbone RMSD). Analysis of the structures seen on the folding pathway reveals details of the folding process unavailable form experiment.

Fluctuating hydrodynamics for multiscale modeling and simulation: energy and heat transfer in molecular fluids.

PubMed

Shang, Barry Z; Voulgarakis, Nikolaos K; Chu, Jhih-Wei

2012-07-28

This work illustrates that fluctuating hydrodynamics (FHD) simulations can be used to capture the thermodynamic and hydrodynamic responses of molecular fluids at the nanoscale, including those associated with energy and heat transfer. Using all-atom molecular dynamics (MD) trajectories as the reference data, the atomistic coordinates of each snapshot are mapped onto mass, momentum, and energy density fields on Eulerian grids to generate a corresponding field trajectory. The molecular length-scale associated with finite molecule size is explicitly imposed during this coarse-graining by requiring that the variances of density fields scale inversely with the grid volume. From the fluctuations of field variables, the response functions and transport coefficients encoded in the all-atom MD trajectory are computed. By using the extracted fluid properties in FHD simulations, we show that the fluctuations and relaxation of hydrodynamic fields quantitatively match with those observed in the reference all-atom MD trajectory, hence establishing compatibility between the atomistic and field representations. We also show that inclusion of energy transfer in the FHD equations can more accurately capture the thermodynamic and hydrodynamic responses of molecular fluids. The results indicate that the proposed MD-to-FHD mapping with explicit consideration of finite molecule size provides a robust framework for coarse-graining the solution phase of complex molecular systems.

Problem formulation for risk assessment of combined exposures to chemicals and other stressors in humans.

PubMed

Solomon, Keith R; Wilks, Martin F; Bachman, Ammie; Boobis, Alan; Moretto, Angelo; Pastoor, Timothy P; Phillips, Richard; Embry, Michelle R

2016-11-01

When the human health risk assessment/risk management paradigm was developed, it did not explicitly include a "problem formulation" phase. The concept of problem formulation was first introduced in the context of ecological risk assessment (ERA) for the pragmatic reason to constrain and focus ERAs on the key questions. However, this need also exists for human health risk assessment, particularly for cumulative risk assessment (CRA), because of its complexity. CRA encompasses the combined threats to health from exposure via all relevant routes to multiple stressors, including biological, chemical, physical and psychosocial stressors. As part of the HESI Risk Assessment in the 21st Century (RISK21) Project, a framework for CRA was developed in which problem formulation plays a critical role. The focus of this effort is primarily on a chemical CRA (i.e., two or more chemicals) with subsequent consideration of non-chemical stressors, defined as "modulating factors" (ModFs). Problem formulation is a systematic approach that identifies all factors critical to a specific risk assessment and considers the purpose of the assessment, scope and depth of the necessary analysis, analytical approach, available resources and outcomes, and overall risk management goal. There are numerous considerations that are specific to multiple stressors, and proper problem formulation can help to focus a CRA to the key factors in order to optimize resources. As part of the problem formulation, conceptual models for exposures and responses can be developed that address these factors, such as temporal relationships between stressors and consideration of the appropriate ModFs.

Symmetry considerations in the scattering of identical composite bodies

NASA Technical Reports Server (NTRS)

Norbury, J. W.; Townsend, L. W.; Deutchman, P. A.

1986-01-01

Previous studies of the interactions between composite particles were extended to the case in which the composites are identical. The form of the total interaction potential matrix elements was obtained, and guidelines for their explicit evaluation were given. For the case of elastic scattering of identical composites, the matrix element approach was shown to be equivalent to the scattering amplitude method.

The Language of the Liberal Consensus: John F. Kennedy, Technical Reason, and the "New Economics" at Yale University

ERIC Educational Resources Information Center

Murphy, John W.

2004-01-01

On June 11, 1962, President John F. Kennedy addressed the economy at Yale University. This essay explains the symbolic charge of his economic rhetoric, a persuasive campaign that enjoyed considerable success and marked the first time that a president took explicit responsibility for the nation's economic performance. I argue that the president…

The Integration of Delta Prime (f)in a Multidimensional Space

NASA Technical Reports Server (NTRS)

Farassat, F.

1999-01-01

Consideration is given to the thickness noise term of the Ffowcs Williams-Hawkings equation when the time derivative is taken explicitly. An interpretation is presented of the integral I = function phi(x)delta-prime(f) dx, where it is initially assumed that the absolute value of Del-f is not equal to 1 on the surface f = 0.

A Primer for DoD Reliability, Maintainability and Safety Standards

DTIC Science & Technology

1988-03-02

the project engineer and the concurrence of their respective managers. The primary consideration in such cases is the thoroughness of the ...basic approaches to the application of environmental stress screening. In one approach, the government explicitly specifies the screens and screening...TO USE DOD-HDBK-344 (USAF) There are two basic approaches to the application of environmental stress

Defining Pre-Katrina New Orleans: The Structural Transformation of Public Education in New Orleans and Historical Memory

ERIC Educational Resources Information Center

Boselovic, Joseph L.

2014-01-01

Although considerable work has been done around the supposed successes and failures of education reform in post-Katrina New Orleans, concerns about the public/private qualities of new policies are often not discussed explicitly. In kind, this article serves to investigate theoretical conceptions of the public as they relate to education while…

Comparative functional neuroanatomy between implicit and explicit memory tasks under negative emotional condition in schizophrenia.

PubMed

Song, Xiao-Li; Kim, Gwang-Won; Moon, Chung-Man; Jeong, Gwang-Woo

To evaluate the brain activation patterns in response to negative emotion during implicit and explicit memory in patients with schizophrenia. Fourteen patients with schizophrenia and 14 healthy controls were included in this study. The 3.0T fMRI was obtained while the subjects performed the implicit and explicit retrievals with unpleasant words. The different predominant brain activation areas were observed during the implicit retrieval and explicit with unpleasant words. The differential neural mechanisms between implicit and explicit memory tasks associated with negative emotional processing in schizophrenia. Copyright © 2017. Published by Elsevier Inc.

ESL Elementary Teachers' Use of Children's Picture Books to Initiate Explicit Instruction of Reading Comprehension Strategies

ERIC Educational Resources Information Center

Al Khaiyali, Al Tiyb S.

2014-01-01

Reading comprehension instruction has been recognized as a key factor in developing any reading and literacy program. Therefore, many attempts were devoted to improve explicit comprehension strategy instruction at different school levels and fields including EFL and ESL. Despite these efforts, explicit comprehension instruction is still drought…

The Effect of Explicit Instruction on Strategic Reading in a Literacy Methods Course

ERIC Educational Resources Information Center

Iwai, Yuko

2016-01-01

This study examined the impact of explicit instruction on metacognitive reading strategies among 18 K-8 teacher candidates in a literacy methods course. They received weekly explicit intervention about these strategies over one semester. Collected data included pre- and post-scores of the Metacognitive Awareness of Reading Strategies Inventory…

Intrusive effects of implicitly processed information on explicit memory.

PubMed

Sentz, Dustin F; Kirkhart, Matthew W; LoPresto, Charles; Sobelman, Steven

2002-02-01

This study described the interference of implicitly processed information on the memory for explicitly processed information. Participants studied a list of words either auditorily or visually under instructions to remember the words (explicit study). They were then visually presented another word list under instructions which facilitate implicit but not explicit processing. Following a distractor task, memory for the explicit study list was tested with either a visual or auditory recognition task that included new words, words from the explicit study list, and words implicitly processed. Analysis indicated participants both failed to recognize words from the explicit study list and falsely recognized words that were implicitly processed as originating from the explicit study list. However, this effect only occurred when the testing modality was visual, thereby matching the modality for the implicitly processed information, regardless of the modality of the explicit study list. This "modality effect" for explicit memory was interpreted as poor source memory for implicitly processed information and in light of the procedures used. as well as illustrating an example of "remembering causing forgetting."

Putting Public Health Ethics into Practice: A Systematic Framework

PubMed Central

Marckmann, Georg; Schmidt, Harald; Sofaer, Neema; Strech, Daniel

2015-01-01

It is widely acknowledged that public health practice raises ethical issues that require a different approach than traditional biomedical ethics. Several frameworks for public health ethics (PHE) have been proposed; however, none of them provides a practice-oriented combination of the two necessary components: (1) a set of normative criteria based on an explicit ethical justification and (2) a structured methodological approach for applying the resulting normative criteria to concrete public health (PH) issues. Building on prior work in the field and integrating valuable elements of other approaches to PHE, we present a systematic ethical framework that shall guide professionals in planning, conducting, and evaluating PH interventions. Based on a coherentist model of ethical justification, the proposed framework contains (1) an explicit normative foundation with five substantive criteria and seven procedural conditions to guarantee a fair decision process, and (2) a six-step methodological approach for applying the criteria and conditions to the practice of PH and health policy. The framework explicitly ties together ethical analysis and empirical evidence, thus striving for evidence-based PHE. It can provide normative guidance to those who analyze the ethical implications of PH practice including academic ethicists, health policy makers, health technology assessment bodies, and PH professionals. It will enable those who implement a PH intervention and those affected by it (i.e., the target population) to critically assess whether and how the required ethical considerations have been taken into account. Thereby, the framework can contribute to assuring the quality of ethical analysis in PH. Whether the presented framework will be able to achieve its goals has to be determined by evaluating its practical application. PMID:25705615

Towards a minimal stochastic model for a large class of diffusion-reactions on biological membranes.

PubMed

Chevalier, Michael W; El-Samad, Hana

2012-08-28

Diffusion of biological molecules on 2D biological membranes can play an important role in the behavior of stochastic biochemical reaction systems. Yet, we still lack a fundamental understanding of circumstances where explicit accounting of the diffusion and spatial coordinates of molecules is necessary. In this work, we illustrate how time-dependent, non-exponential reaction probabilities naturally arise when explicitly accounting for the diffusion of molecules. We use the analytical expression of these probabilities to derive a novel algorithm which, while ignoring the exact position of the molecules, can still accurately capture diffusion effects. We investigate the regions of validity of the algorithm and show that for most parameter regimes, it constitutes an accurate framework for studying these systems. We also document scenarios where large spatial fluctuation effects mandate explicit consideration of all the molecules and their positions. Taken together, our results derive a fundamental understanding of the role of diffusion and spatial fluctuations in these systems. Simultaneously, they provide a general computational methodology for analyzing a broad class of biological networks whose behavior is influenced by diffusion on membranes.

Explicit and implicit reinforcement learning across the psychosis spectrum.

PubMed

Barch, Deanna M; Carter, Cameron S; Gold, James M; Johnson, Sheri L; Kring, Ann M; MacDonald, Angus W; Pizzagalli, Diego A; Ragland, J Daniel; Silverstein, Steven M; Strauss, Milton E

2017-07-01

Motivational and hedonic impairments are core features of a variety of types of psychopathology. An important aspect of motivational function is reinforcement learning (RL), including implicit (i.e., outside of conscious awareness) and explicit (i.e., including explicit representations about potential reward associations) learning, as well as both positive reinforcement (learning about actions that lead to reward) and punishment (learning to avoid actions that lead to loss). Here we present data from paradigms designed to assess both positive and negative components of both implicit and explicit RL, examine performance on each of these tasks among individuals with schizophrenia, schizoaffective disorder, and bipolar disorder with psychosis, and examine their relative relationships to specific symptom domains transdiagnostically. None of the diagnostic groups differed significantly from controls on the implicit RL tasks in either bias toward a rewarded response or bias away from a punished response. However, on the explicit RL task, both the individuals with schizophrenia and schizoaffective disorder performed significantly worse than controls, but the individuals with bipolar did not. Worse performance on the explicit RL task, but not the implicit RL task, was related to worse motivation and pleasure symptoms across all diagnostic categories. Performance on explicit RL, but not implicit RL, was related to working memory, which accounted for some of the diagnostic group differences. However, working memory did not account for the relationship of explicit RL to motivation and pleasure symptoms. These findings suggest transdiagnostic relationships across the spectrum of psychotic disorders between motivation and pleasure impairments and explicit RL. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Thalamic volume deficit contributes to procedural and explicit memory impairment in HIV infection with primary alcoholism comorbidity.

PubMed

Fama, Rosemary; Rosenbloom, Margaret J; Sassoon, Stephanie A; Rohlfing, Torsten; Pfefferbaum, Adolf; Sullivan, Edith V

2014-12-01

Component cognitive and motor processes contributing to diminished visuomotor procedural learning in HIV infection with comorbid chronic alcoholism (HIV+ALC) include problems with attention and explicit memory processes. The neural correlates associated with this constellation of cognitive and motor processes in HIV infection and alcoholism have yet to be delineated. Frontostriatal regions are affected in HIV infection, frontothalamocerebellar regions are affected in chronic alcoholism, and frontolimbic regions are likely affected in both; all three of these systems have the potential of contributing to both visuomotor procedural learning and explicit memory processes. Here, we examined the neural correlates of implicit memory, explicit memory, attention, and motor tests in 26 HIV+ALC (5 with comorbidity for nonalcohol drug abuse/dependence) and 19 age-range matched healthy control men. Parcellated brain volumes, including cortical, subcortical, and allocortical regions, as well as cortical sulci and ventricles, were derived using the SRI24 brain atlas. Results indicated that smaller thalamic volumes were associated with poorer performance on tests of explicit (immediate and delayed) and implicit (visuomotor procedural) memory in HIV+ALC. By contrast, smaller hippocampal volumes were associated with lower scores on explicit, but not implicit memory. Multiple regression analyses revealed that volumes of both the thalamus and the hippocampus were each unique independent predictors of explicit memory scores. This study provides evidence of a dissociation between implicit and explicit memory tasks in HIV+ALC, with selective relationships observed between hippocampal volume and explicit but not implicit memory, and highlights the relevance of the thalamus to mnemonic processes.

PIRLS 2011 User Guide for the International Database. Supplement 4: PIRLS 2011 Sampling Stratification Information

ERIC Educational Resources Information Center

Foy, Pierre, Ed.; Drucker, Kathleen T., Ed.

2013-01-01

This supplement contains documentation on the explicit and implicit stratification variables included in the PIRLS 2011 data files. The explicit strata are smaller sampling frames, created from the national sampling frames, from which national samples of schools were drawn. The implicit strata are nested within the explicit strata, and were used…

TIMSS 2011 User Guide for the International Database. Supplement 4: TIMSS 2011 Sampling Stratification Information

ERIC Educational Resources Information Center

Foy, Pierre, Ed.; Arora, Alka, Ed.; Stanco, Gabrielle M., Ed.

2013-01-01

This supplement contains documentation on the explicit and implicit stratification variables included in the TIMSS 2011 data files. The explicit strata are smaller sampling frames, created from the national sampling frames, from which national samples of schools were drawn. The implicit strata are nested within the explicit strata, and were used…

'It was a freak accident': an analysis of the labelling of injury events in the US press.

PubMed

Smith, Katherine C; Girasek, Deborah C; Baker, Susan P; Manganello, Jennifer A; Bowman, Stephen M; Samuels, Alicia; Gielen, Andrea C

2012-02-01

Given that the news media shape our understanding of health issues, a study was undertaken to examine the use by the US media of the expression 'freak accident' in relation to injury events. This analysis is intended to contribute to the ongoing consideration of lay conceptualisation of injuries as 'accidents'. LexisNexis Academic was used to search three purposively selected US news sources (Associated Press, New York Times and Philadelphia Inquirer) for the expression 'freak accident' over 5 years (2005-9). Textual analysis included both structured and open coding. Coding included measures for who used the expression within the story, the nature of the injury event and the injured person(s) being reported upon, incorporation of prevention information within the story and finally a phenomenological consideration of the uses and meanings of the expression within the story context. Results The search yielded a dataset of 250 human injury stories incorporating the term 'freak accident'. Injuries sustained by professional athletes dominated coverage (61%). Fewer than 10% of stories provided a clear and explicit injury prevention message. Stories in which journalists employed the expression 'freak accident' were less likely to include prevention information than stories in which the expression was used by people quoted in the story. Journalists who frame injury events as freak accidents may be an appropriate focus for advocacy efforts. Effective prevention messages should be developed and disseminated to accompany injury reporting in order to educate and protect the public.

Singing over the Wall: Legal and Ethical Considerations for Sacred Music in the Public Schools

ERIC Educational Resources Information Center

Drummond, Tim

2014-01-01

Music with sacred texts is integral to the historical and modern development of the music education field, yet many who teach in public schools find themselves limited or banned from using sacred music. School divisions do not have a consensus opinion on how to handle this sensitive topic, and the law is not explicit. In this article, I provide an…

Reading the Bible as a Pedagogical Text: Testing, Testament, and Some Postmodern Considerations about Religion/the Bible in Contemporary Education

ERIC Educational Resources Information Center

Segall, Avner; Burke, Kevin

2013-01-01

While it is true that following various Supreme Court decisions in the last century, religion is, in most cases, no longer explicitly taught in public school classrooms, we use this article to explore the ways in which implicit religious understandings regarding curriculum and pedagogy still remain prevalent in current public education. Building…

What Is "Known" in Community Music in Higher Education? Engagement, Emotional Learning and an Ecology of Ideas from the Student Perspective

ERIC Educational Resources Information Center

Mellor, Liz

2011-01-01

This article aims to make explicit the evolving ecology of ideas in the field of community music and higher education that are particular to a context yet transferable across respective fields of enquiry--music education, community music, music therapy and community music therapy. This is contextualized in two ways: (1) through a consideration of…

Chemically frozen multicomponent boundary layer theory of salt and/or ash deposition rates from combustion gases

NASA Technical Reports Server (NTRS)

Rosner, D. E.; Chen, B.-K.; Fryburg, G. C.; Kohl, F. J.

1979-01-01

There is increased interest in, and concern about, deposition and corrosion phenomena in combustion systems containing inorganic condensible vapors and particles (salts, ash). To meet the need for a computationally tractable deposition rate theory general enough to embrace multielement/component situations of current and future gas turbine and magnetogasdynamic interest, a multicomponent chemically 'frozen' boundary layer (CFBL) deposition theory is presented and its applicability to the special case of Na2SO4 deposition from seeded laboratory burner combustion products is demonstrated. The coupled effects of Fick (concentration) diffusion and Soret (thermal) diffusion are included, along with explicit corrections for effects of variable properties and free stream turbulence. The present formulation is sufficiently general to include the transport of particles provided they are small enough to be formally treated as heavy molecules. Quantitative criteria developed to delineate the domain of validity of CFBL-rate theory suggest considerable practical promise for the present framework, which is characterized by relatively modest demands for new input information and computer time.

The importance of values in evidence-based medicine.

PubMed

Kelly, Michael P; Heath, Iona; Howick, Jeremy; Greenhalgh, Trisha

2015-10-12

Evidence-based medicine (EBM) has always required integration of patient values with 'best' clinical evidence. It is widely recognized that scientific practices and discoveries, including those of EBM, are value-laden. But to date, the science of EBM has focused primarily on methods for reducing bias in the evidence, while the role of values in the different aspects of the EBM process has been almost completely ignored. In this paper, we address this gap by demonstrating how a consideration of values can enhance every aspect of EBM, including: prioritizing which tests and treatments to investigate, selecting research designs and methods, assessing effectiveness and efficiency, supporting patient choice and taking account of the limited time and resources available to busy clinicians. Since values are integral to the practice of EBM, it follows that the highest standards of EBM require values to be made explicit, systematically explored, and integrated into decision making. Through 'values based' approaches, EBM's connection to the humanitarian principles upon which it was founded will be strengthened.

Approaches to assessment in time-limited Mentalization-Based Therapy for Children (MBT-C)

PubMed Central

Muller, Nicole; Midgley, Nick

2015-01-01

In this article we describe our clinical approach to assessment, formulation and the identification of a therapeutic focus in the context of time-limited Mentalization-Based Treatment for Children (MBT-C) aged between 6 and 12. Rather than seeing the capacity to mentalize as a global construct, we set out an approach to assessing the developmental ‘building blocks’ of the capacity to mentalize the self and others, including the capacity for attention regulation, emotion regulation, and explicit mentalization. Assessing the child’s strengths and vulnerabilities in each of these domains provides a more nuanced picture of the child’s mentalizing capacities and difficulties, and can provide a useful approach to case formulation. The article sets out an approach to assessment that includes a consideration of mentalizing strengths and difficulties in both the child and the parents, and shows how this can be used to help develop a mutually agreed treatment focus. A clinical vignette illustrates the approach taken to assessment and connects it to routine clinical practice. PMID:26283994

Magnetic design for the PediaFlow ventricular assist device.

PubMed

Noh, Myounggyu D; Antaki, James F; Ricci, Michael; Gardiner, Jeff; Paden, Dave; Wu, Jingchun; Prem, Ed; Borovetz, Harvey; Paden, Bradley E

2008-02-01

This article describes a design process for a new pediatric ventricular assist device, the PediaFlow. The pump is embodied in a magnetically levitated turbodynamic design that was developed explicitly based on the requirements for chronic support of infants and small children. The procedure entailed the consideration of multiple pump topologies, from which an axial mixed-flow configuration was chosen for further development. The magnetic design includes permanent-magnet (PM) passive bearings for radial support of the rotor, an actively controlled thrust actuator for axial support, and a brushless direct current (DC) motor for rotation. These components are closely coupled both geometrically and magnetically, and were therefore optimized in parallel, using electromagnetic, rotordynamic models and fluid models, and in consideration of hydrodynamic requirements. Multiple design objectives were considered, including efficiency, size, and margin between critical speeds to operating speed. The former depends upon the radial and yaw stiffnesses of the PM bearings. Analytical expressions for the stiffnesses were derived and verified through finite element analysis (FEA). A toroidally wound motor was designed for high efficiency and minimal additional negative radial stiffness. The design process relies heavily on optimization at the component level and system level. The results of this preliminary design optimization yielded a pump design with an overall stability margin of 15%, based on a pressure rise of 100 mm Hg at 0.5 lpm running at 16,000 rpm.

Resource allocation in health care and the role of personal autonomy.

PubMed

Gandjour, A

2015-03-01

Resource allocation decisions in health care require the consideration of ethical values. Major ethical theories include Amartya Sen's capability approach, Norman Daniels's theory of justice for health, and preference utilitarian theory. This paper argues that while only preference utilitarian theory explicitly considers the impact of an individual's actions on others, all 3 theories agree in terms of providing individual autonomy. Furthermore, it shows that all 3 theories emphasise the role of informed preferences in securing individual autonomy. Still, stressing personal autonomy has limited direct implications for priority setting. 2 priority rules for resource allocation could be identified: 1) to give priority to patients with mental disability (over those with pure physical disability); and 2) to give priority to patients with a large expected loss of autonomy without treatment. © Georg Thieme Verlag KG Stuttgart · New York.

Evaluating lightning hazards to building environments using explicit numerical solutions of Maxwell's equations

NASA Astrophysics Data System (ADS)

Collier, Richard S.; McKenna, Paul M.; Perala, Rodney A.

1991-08-01

The objective here is to describe the lightning hazards to buildings and their internal environments using advanced formulations of Maxwell's Equations. The method described is the Three Dimensional Finite Difference Time Domain Solution. It can be used to solve for the lightning interaction with such structures in three dimensions with the inclusion of a considerable amount of detail. Special techniques were developed for including wire, plumbing, and rebar into the model. Some buildings have provisions for lightning protection in the form of air terminals connected to a ground counterpoise system. It is shown that fields and currents within these structures can be significantly high during a lightning strike. Time lapse video presentations were made showing the electric and magnetic field distributions on selected cross sections of the buildings during a simulated lightning strike.

Evaluating lightning hazards to building environments using explicit numerical solutions of Maxwell's equations

NASA Technical Reports Server (NTRS)

Collier, Richard S.; Mckenna, Paul M.; Perala, Rodney A.

1991-01-01

The objective here is to describe the lightning hazards to buildings and their internal environments using advanced formulations of Maxwell's Equations. The method described is the Three Dimensional Finite Difference Time Domain Solution. It can be used to solve for the lightning interaction with such structures in three dimensions with the inclusion of a considerable amount of detail. Special techniques were developed for including wire, plumbing, and rebar into the model. Some buildings have provisions for lightning protection in the form of air terminals connected to a ground counterpoise system. It is shown that fields and currents within these structures can be significantly high during a lightning strike. Time lapse video presentations were made showing the electric and magnetic field distributions on selected cross sections of the buildings during a simulated lightning strike.

Algebraic grid generation for coolant passages of turbine blades with serpentine channels and pin fins

NASA Technical Reports Server (NTRS)

Shih, T. I.-P.; Roelke, R. J.; Steinthorsson, E.

1991-01-01

In order to study numerically details of the flow and heat transfer within coolant passages of turbine blades, a method must first be developed to generate grid systems within the very complicated geometries involved. In this study, a grid generation package was developed that is capable of generating the required grid systems. The package developed is based on an algebraic grid generation technique that permits the user considerable control over how grid points are to be distributed in a very explicit way. These controls include orthogonality of grid lines next to boundary surfaces and ability to cluster about arbitrary points, lines, and surfaces. This paper describes that grid generation package and shows how it can be used to generate grid systems within complicated-shaped coolant passages via an example.

Time Series Expression Analyses Using RNA-seq: A Statistical Approach

PubMed Central

Oh, Sunghee; Song, Seongho; Grabowski, Gregory; Zhao, Hongyu; Noonan, James P.

2013-01-01

RNA-seq is becoming the de facto standard approach for transcriptome analysis with ever-reducing cost. It has considerable advantages over conventional technologies (microarrays) because it allows for direct identification and quantification of transcripts. Many time series RNA-seq datasets have been collected to study the dynamic regulations of transcripts. However, statistically rigorous and computationally efficient methods are needed to explore the time-dependent changes of gene expression in biological systems. These methods should explicitly account for the dependencies of expression patterns across time points. Here, we discuss several methods that can be applied to model timecourse RNA-seq data, including statistical evolutionary trajectory index (SETI), autoregressive time-lagged regression (AR(1)), and hidden Markov model (HMM) approaches. We use three real datasets and simulation studies to demonstrate the utility of these dynamic methods in temporal analysis. PMID:23586021

Economic lot sizing in a production system with random demand

NASA Astrophysics Data System (ADS)

Lee, Shine-Der; Yang, Chin-Ming; Lan, Shu-Chuan

2016-04-01

An extended economic production quantity model that copes with random demand is developed in this paper. A unique feature of the proposed study is the consideration of transient shortage during the production stage, which has not been explicitly analysed in existing literature. The considered costs include set-up cost for the batch production, inventory carrying cost during the production and depletion stages in one replenishment cycle, and shortage cost when demand cannot be satisfied from the shop floor immediately. Based on renewal reward process, a per-unit-time expected cost model is developed and analysed. Under some mild condition, it can be shown that the approximate cost function is convex. Computational experiments have demonstrated that the average reduction in total cost is significant when the proposed lot sizing policy is compared with those with deterministic demand.

Time series expression analyses using RNA-seq: a statistical approach.

PubMed

Oh, Sunghee; Song, Seongho; Grabowski, Gregory; Zhao, Hongyu; Noonan, James P

2013-01-01

RNA-seq is becoming the de facto standard approach for transcriptome analysis with ever-reducing cost. It has considerable advantages over conventional technologies (microarrays) because it allows for direct identification and quantification of transcripts. Many time series RNA-seq datasets have been collected to study the dynamic regulations of transcripts. However, statistically rigorous and computationally efficient methods are needed to explore the time-dependent changes of gene expression in biological systems. These methods should explicitly account for the dependencies of expression patterns across time points. Here, we discuss several methods that can be applied to model timecourse RNA-seq data, including statistical evolutionary trajectory index (SETI), autoregressive time-lagged regression (AR(1)), and hidden Markov model (HMM) approaches. We use three real datasets and simulation studies to demonstrate the utility of these dynamic methods in temporal analysis.

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

Wieder, William R.; Allison, Steven D.; Davidson, Eric A.

Microbes influence soil organic matter (SOM) decomposition and the long-term stabilization of carbon (C) in soils. We contend that by revising the representation of microbial processes and their interactions with the physicochemical soil environment, Earth system models (ESMs) may make more realistic global C cycle projections. Explicit representation of microbial processes presents considerable challenges due to the scale at which these processes occur. Thus, applying microbial theory in ESMs requires a framework to link micro-scale process-level understanding and measurements to macro-scale models used to make decadal- to century-long projections. Here, we review the diversity, advantages, and pitfalls of simulating soilmore » biogeochemical cycles using microbial-explicit modeling approaches. We present a roadmap for how to begin building, applying, and evaluating reliable microbial-explicit model formulations that can be applied in ESMs. Drawing from experience with traditional decomposition models we suggest: (1) guidelines for common model parameters and output that can facilitate future model intercomparisons; (2) development of benchmarking and model-data integration frameworks that can be used to effectively guide, inform, and evaluate model parameterizations with data from well-curated repositories; and (3) the application of scaling methods to integrate microbial-explicit soil biogeochemistry modules within ESMs. With contributions across scientific disciplines, we feel this roadmap can advance our fundamental understanding of soil biogeochemical dynamics and more realistically project likely soil C response to environmental change at global scales.« less

Scalable explicit implementation of anisotropic diffusion with Runge-Kutta-Legendre super-time stepping

NASA Astrophysics Data System (ADS)

Vaidya, Bhargav; Prasad, Deovrat; Mignone, Andrea; Sharma, Prateek; Rickler, Luca

2017-12-01

An important ingredient in numerical modelling of high temperature magnetized astrophysical plasmas is the anisotropic transport of heat along magnetic field lines from higher to lower temperatures. Magnetohydrodynamics typically involves solving the hyperbolic set of conservation equations along with the induction equation. Incorporating anisotropic thermal conduction requires to also treat parabolic terms arising from the diffusion operator. An explicit treatment of parabolic terms will considerably reduce the simulation time step due to its dependence on the square of the grid resolution (Δx) for stability. Although an implicit scheme relaxes the constraint on stability, it is difficult to distribute efficiently on a parallel architecture. Treating parabolic terms with accelerated super-time-stepping (STS) methods has been discussed in literature, but these methods suffer from poor accuracy (first order in time) and also have difficult-to-choose tuneable stability parameters. In this work, we highlight a second-order (in time) Runge-Kutta-Legendre (RKL) scheme (first described by Meyer, Balsara & Aslam 2012) that is robust, fast and accurate in treating parabolic terms alongside the hyperbolic conversation laws. We demonstrate its superiority over the first-order STS schemes with standard tests and astrophysical applications. We also show that explicit conduction is particularly robust in handling saturated thermal conduction. Parallel scaling of explicit conduction using RKL scheme is demonstrated up to more than 104 processors.

Desire for autonomy in health care decisions: a general population survey.

PubMed

Cullati, Stéphane; Courvoisier, Delphine S; Charvet-Bérard, Agathe I; Perneger, Thomas V

2011-04-01

To examine factors associated with desire for autonomy in health care decisions in the general population. Mailed survey of 2348 residents of Geneva, Switzerland. Participants answered questions on a scale measuring their desire for autonomy in health care decisions. The scale was scored between 0 (lowest desire for autonomy) and 100 (highest desire for autonomy). On average the respondents favoured shared or active involvement in medical decisions (mean score 62.0, SD 20.9), but attitudes varied considerably. In the multivariate model, factors associated with a higher desire for autonomy included female gender, younger age, higher education, living alone, reporting an excellent global health and - a new observation compared to previous studies - having made several medical decisions in the past 6 months. The attitudes of the general public appear to be consistent with the model of shared decision making. However, people vary considerably in their desire for autonomy. An explicit assessment of each individual's desire for autonomy may improve the decision-making process. Such an assessment should be repeated regularly, as familiarity with medical decisions may increase the desire for autonomy. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Do Public Involvement Activities in Biomedical Research and Innovation Recruit Representatively? A Systematic Qualitative Review.

PubMed

Lander, Jonas; Hainz, Tobias; Hirschberg, Irene; Bossert, Sabine; Strech, Daniel

2016-01-01

Public involvement activities (PIAs) may contribute to the governance of ethically challenging biomedical research and innovation by informing, consulting with and engaging the public in developments and decision-making processes. For PIAs to capture a population's preferences (e.g. on issues in whole genome sequencing, biobanks or genome editing), a central methodological requirement is to involve a sufficiently representative subgroup of the general public. While the existing literature focusses on theoretical and normative aspects of 'representation', this study assesses empirically how such considerations are implemented in practice. It evaluates how PIA reports describe representation objectives, the recruitment process and levels of representation achieved. PIA reports were included from a systematic literature search if they directly reported a PIA conducted in a relevant discipline such as genomics, biobanks, biotechnology or others. PIA reports were analyzed with thematic text analysis. The text analysis was guided by an assessment matrix based on PIA-specific guidelines and frameworks. We included 46 relevant reports, most focusing on issues in genomics. 27 reports (59%) explicitly described representation objectives, though mostly without adjusting eligibility criteria and recruiting methods to the specific objective. 11 reports (24%) explicitly reported to have achieved the intended representation; the rest either reported failure or were silent on this issue. Representation of study samples in PIAs in biomedical research and innovation is currently not reported systematically. Improved reporting on representation would not only improve the validity and value of PIAs, but could also contribute to PIA results being used more often in relevant policy and decision-making processes. © 2016 S. Karger AG, Basel.

Sexting, substance use, and sexual risk behavior in young adults

PubMed Central

Benotsch, Eric G.; Snipes, Daniel J.; Martin, Aaron M.; Bull, Sheana S.

2012-01-01

Purpose Cell phone use has become more widespread over the past decade. Young adults are frequently early adopters of new technologies, including cell phones. Most prior research examining sexting, the act of sending sexually explicit or suggestive images via text message, has focused on the legal or social consequences of this behavior. The current study focused on the public health implications of sexting by examining associations between sexting, substance use, and sexual risk behavior in youth. Methods Young adults (N=763) completed online questionnaires assessing demographics, cell phone use (e.g., texting, sexting), substance use, and sexual risk behaviors. Results Sexting was reported by a substantial minority of participants (44%). Compared to their non-sexting counterparts, participants who engaged in sexting were more likely to report recent substance use and high-risk sexual behaviors, including unprotected sex and sex with multiple partners. Of those who engaged in sexting, a considerable percentage (31.8%) reported having sex with a new partner for the first time after sexting with that person. In multivariate analyses, sexting was associated with high-risk sexual behavior after accounting for demographic factors, total texting behaviors, and substance use. Conclusions Results suggest that sexting is robustly associated with high-risk sexual behavior. Many individuals exchange explicit or provocative photos with long-term sexual partners, but at least some participants in this study were incurring new sexual risks subsequent to sexting. Additional research is needed to understand the contexts in which sexting occurs, motivations for sexting, and relationship of sexting to risk behavior. PMID:23299017

Sexting, substance use, and sexual risk behavior in young adults.

PubMed

Benotsch, Eric G; Snipes, Daniel J; Martin, Aaron M; Bull, Sheana S

2013-03-01

Cell phone use has become more widespread over the past decade. Young adults are frequently early adopters of new technologies, including cell phones. Most previous research examining sexting, the act of sending sexually explicit or suggestive images via text message, has focused on the legal or social consequences of this behavior. The current study focused on the public health implications of sexting by examining associations between sexting, substance use, and sexual risk behavior in youth. Young adults (N = 763) completed online questionnaires assessing demographics, cell phone use (e.g., texting, sexting), substance use, and sexual risk behaviors. Sexting was reported by a substantial minority of participants (44%). Compared with their nonsexting counterparts, participants who engaged in sexting were more likely to report recent substance use and high-risk sexual behaviors, including unprotected sex and sex with multiple partners. Of those who engaged in sexting, a considerable percentage (31.8%) reported having sex with a new partner for the first time after sexting with that person. In multivariate analyses, sexting was associated with high-risk sexual behavior, after accounting for demographic factors, total texting behaviors, and substance use. Results suggest that sexting is robustly associated with high-risk sexual behavior. Many individuals exchange explicit or provocative photos with long-term sexual partners, but at least some participants in this study were incurring new sexual risks after sexting. Additional research is needed to understand the contexts in which sexting occurs, motivations for sexting, and relationship of sexting to risk behavior. Copyright © 2013 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

At the nexus of fire, water and society

USGS Publications Warehouse

Martin, Deborah

2016-01-01

The societal risks of water scarcity and water-quality impairment have received considerable attention, evidenced by recent analyses of these topics by the 2030 Water Resources Group, the United Nations and the World Economic Forum. What are the effects of fire on the predicted water scarcity and declines in water quality? Drinking water supplies for humans, the emphasis of this exploration, are derived from several land cover types, including forests, grasslands and peatlands, which are vulnerable to fire. In the last two decades, fires have affected the water supply catchments of Denver (CO) and other southwestern US cities, and four major Australian cities including Sydney, Canberra, Adelaide and Melbourne. In the same time period, several, though not all, national, regional and global water assessments have included fire in evaluations of the risks that affect water supplies. The objective of this discussion is to explore the nexus of fire, water and society with the hope that a more explicit understanding of fire effects on water supplies will encourage the incorporation of fire into future assessments of water supplies, into the pyrogeography conceptual framework and into planning efforts directed at water resiliency.

Using Synchronous Videoconferencing to Deliver Family-Based Mental Healthcare.

PubMed

Crum, Kathleen I; Comer, Jonathan S

2016-04-01

Leading telemental healthcare programs are increasingly harnessing new technologies in innovative ways to broaden the reach of supported care for children and adolescents. Technology-based delivery methods drawing on synchronous videoteleconferencing can transcend geographic barriers to quality care and remotely provide real-time services to affected families, regardless of their proximity to an expert mental health facility. The present review considers critical issues specific to family-based telemental healthcare, including: 1) Navigating varying levels of technological literacy across generations of participants; 2) deciding which family members to include in family-based telemental healthcare; 3) ensuring the safety of participants in family-based telemental healthcare; 4) optimizing therapeutic alliance and engagement in family-based telemental healthcare; 5) navigating logistical concerns in the conducting of sessions; and 6) ensuring privacy in family-based telemental healthcare. We discuss illustrations of recent child telemental healthcare advances that have focused explicitly on family-based treatment approaches, including Internet-delivered Parent-Child Interaction Therapy and Internet-delivered family-based cognitive-behavioral therapy for early-onset OCD. We conclude with a consideration of future directions for the field of family-based telemental healthcare.

Implicit and explicit social mentalizing: dual processes driven by a shared neural network

PubMed Central

Van Overwalle, Frank; Vandekerckhove, Marie

2013-01-01

Recent social neuroscientific evidence indicates that implicit and explicit inferences on the mind of another person (i.e., intentions, attributions or traits), are subserved by a shared mentalizing network. Under both implicit and explicit instructions, ERP studies reveal that early inferences occur at about the same time, and fMRI studies demonstrate an overlap in core mentalizing areas, including the temporo-parietal junction (TPJ) and the medial prefrontal cortex (mPFC). These results suggest a rapid shared implicit intuition followed by a slower explicit verification processes (as revealed by additional brain activation during explicit vs. implicit inferences). These data provide support for a default-adjustment dual-process framework of social mentalizing. PMID:24062663

Systematic review of the methodological quality of clinical guideline development for the management of chronic disease in Europe.

PubMed

Knai, Cécile; Brusamento, Serena; Legido-Quigley, Helena; Saliba, Vanessa; Panteli, Dimitra; Turk, Eva; Car, Josip; McKee, Martin; Busse, Reinhard

2012-10-01

The use of evidence-based clinical guidelines is an essential component of chronic disease management. However, there is well-documented concern about variability in the quality of clinical guidelines, with evidence of persisting methodological shortcomings. The most widely accepted approach to assessing the quality of guidelines is the Appraisal of Guidelines for Research and Evaluation (AGREE) instrument. We have conducted a systematic review of the methodological quality (as assessed by AGREE) of clinical guidelines developed in Europe for the management of chronic diseases published since 2000. The systematic review was undertaken in accordance with the Cochrane methodology. The inclusion criteria were that studies should have appraised European clinical guidelines for certain selected chronic disorders using the AGREE instrument. We searched five databases (Cab Abstracts, EMBASE, MEDLINE, Trip and EPPI). Nine studies reported in 10 papers, analysing a total of 28 European guidelines from eight countries as well as pan-European, were included. There was considerable variation in the quality of clinical guidelines across the AGREE domains. The least well addressed domains were 'editorial independence' (with a mean domain score of 41%), 'applicability' (44%), 'stakeholder involvement' (55%), and 'rigour of development' (64%), while 'clarity of presentation' (80%) and 'scope and purpose' (84%) were less problematic. This review indicates that there is considerable scope for improvement in the methods used to develop clinical guidelines for the prevention, management and treatment of chronic diseases in Europe. Given the importance of decision support strategies such as clinical guidelines in chronic disease management, improvement measures should include the explicit and transparent involvement of key stakeholders (especially scientific experts, guideline users and methodological specialists) and consideration of the implications for guideline implementation and applicability early on in the process. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

The Impact of Explicit, Self-Regulatory Reading Comprehension Strategy Instruction on the Reading-Specific Self-Efficacy, Attributions, and Affect of Students with Reading Disabilities

ERIC Educational Resources Information Center

Nelson, Jason M.; Manset-Williamson, Genevieve

2006-01-01

We compared a reading intervention that consisted of explicit, self-regulatory strategy instruction to a strategy intervention that was less explicit to determine the impact on the reading-specific self-efficacy, attributions, and affect of students with reading disabilities (RD). Participants included 20 students with RD who were entering grades…

Effects of Explicit Instruction on the Acquisition of Students' Science Inquiry Skills in Grades 5 and 6 of Primary Education

ERIC Educational Resources Information Center

Kruit, P. M.; Oostdam, R. J.; van den Berg, E.; Schuitema, J. A.

2018-01-01

In most primary science classes, students are taught science inquiry skills by way of learning by doing. Research shows that explicit instruction may be more effective. The aim of this study was to investigate the effects of explicit instruction on the acquisition of inquiry skills. Participants included 705 Dutch fifth and sixth graders. Students…

On lattice chiral gauge theories

NASA Technical Reports Server (NTRS)

Maiani, L.; Rossi, G. C.; Testa, M.

1991-01-01

The Smit-Swift-Aoki formulation of a lattice chiral gauge theory is presented. In this formulation the Wilson and other non invariant terms in the action are made gauge invariant by the coupling with a nonlinear auxilary scalar field, omega. It is shown that omega decouples from the physical states only if appropriate parameters are tuned so as to satisfy a set of BRST identities. In addition, explicit ghost fields are necessary to ensure decoupling. These theories can give rise to the correct continuum limit. Similar considerations apply to schemes with mirror fermions. Simpler cases with a global chiral symmetry are discussed and it is shown that the theory becomes free at decoupling. Recent numerical simulations agree with those considerations.

Commentary: Writing and Evaluating Qualitative Research Reports

PubMed Central

Thompson, Deborah; Aroian, Karen J.; McQuaid, Elizabeth L.; Deatrick, Janet A.

2016-01-01

Objective To provide an overview of qualitative methods, particularly for reviewers and authors who may be less familiar with qualitative research. Methods A question and answer format is used to address considerations for writing and evaluating qualitative research. Results and Conclusions When producing qualitative research, individuals are encouraged to address the qualitative research considerations raised and to explicitly identify the systematic strategies used to ensure rigor in study design and methods, analysis, and presentation of findings. Increasing capacity for review and publication of qualitative research within pediatric psychology will advance the field’s ability to gain a better understanding of the specific needs of pediatric populations, tailor interventions more effectively, and promote optimal health. PMID:27118271

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

Ji Zhengfeng; Feng Yuan; Ying Mingsheng

Local quantum operations and classical communication (LOCC) put considerable constraints on many quantum information processing tasks such as cloning and discrimination. Surprisingly, however, discrimination of any two pure states survives such constraints in some sense. We show that cloning is not that lucky; namely, probabilistic LOCC cloning of two product states is strictly less efficient than global cloning. We prove our result by giving explicitly the efficiency formula of local cloning of any two product states.

A discussion supporting presumed consent for posthumous sperm procurement and conception.

PubMed

Tremellen, Kelton; Savulescu, Julian

2015-01-01

Conception of a child using cryopreserved sperm from a deceased man is generally considered ethically sound provided explicit consent for its use has been made, thereby protecting the man's autonomy. When death is sudden (trauma, unexpected illness), explicit consent is not possible, thereby preventing posthumous sperm procurement (PSP) and conception according to current European Society of Human Reproduction and Embryology and the American Society for Reproductive Medicine guidelines. Here, we argue that autonomy of a deceased person should not be considered the paramount ethical concern, but rather consideration of the welfare of the living (widow and prospective child) should be the primary focus. Posthumous conception can bring significant advantages to the widow and her resulting child, with most men supporting such practice. We suggest that a deceased man can benefit from posthumous conception (continuation of his 'bloodline', allowing his widow's wishes for a child to be satisfied), and has a moral duty to allow his widow access to his sperm, if she so wishes, unless he clearly indicated that he did not want children when alive. We outline the arguments favouring presumed consent over implied or proxy consent, plus practical considerations for recording men's wishes to opt-out of posthumous conception. Copyright © 2014 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

Pre-gilbertian conceptions of terrestrial magnetism

USGS Publications Warehouse

Smith, P.J.

1968-01-01

It is now well known that William Gilbert, in his De Magnete of 1600, first suggested that the earth behaves as a great magnet. By their very nature, however, such explicit statements tend, in retrospect, to be emphasised at the expense of less explicit antecedent ideas and experiments, with the result that, in the example under consideration here, the impression has sometimes been given that before Gilbert there was not the slightest suspicion that the earth exerts influence on the magnetic needle. In fact, Gilbert's conclusion represented the culmination of many centuries of thought and experimentation on the subject. This essay traces the main steps in the evolutionary process from the idea that magnetic 'virtue' derived from the heave, through the gradual realisation that magnetism is closely associated with the earth, up to the time of Gilbert's definite statement. ?? 1968.

Using effort information with change-in-ratio data for population estimation

USGS Publications Warehouse

Udevitz, Mark S.; Pollock, Kenneth H.

1995-01-01

Most change-in-ratio (CIR) methods for estimating fish and wildlife population sizes have been based only on assumptions about how encounter probabilities vary among population subclasses. When information on sampling effort is available, it is also possible to derive CIR estimators based on assumptions about how encounter probabilities vary over time. This paper presents a generalization of previous CIR models that allows explicit consideration of a range of assumptions about the variation of encounter probabilities among subclasses and over time. Explicit estimators are derived under this model for specific sets of assumptions about the encounter probabilities. Numerical methods are presented for obtaining estimators under the full range of possible assumptions. Likelihood ratio tests for these assumptions are described. Emphasis is on obtaining estimators based on assumptions about variation of encounter probabilities over time.

[The development of health information with the involvement of consumers at the German Institute for Quality and Efficiency in Health Care (IQWiG)].

PubMed

Zschorlich, B; Knelangen, M; Bastian, H

2011-07-01

The German Institute for Quality and Efficiency in Health Care (IQWiG) began publishing free bi-lingual (German/English) evidence-based health information in February 2006 on the website, http://www.gesundheitsinformation.de http://www.informedhealthonline.org . The Institute aims to be a patient-centred and non-directive provider of health information to the public and patients. The point of view and information needs of the public are a central element in the development of health information. People can be involved implicitly or explicitly. People can participate directly or explicitly in health information, for example, by suggesting a topic, by helping shape the content and during the development process. We do this in several ways, including surveys, consultation with consumer representatives as well as through user-testing and reader online rating. In addition, implicit involvement of patients occurs indirectly through consideration of the experiences and information needs of patients via an analysis of qualitative research. A challenge here is the generalisability of information derived from research in other cultures. The Institute monitors methodological developments in the area of patient and health information, to keep its methods up-to-date. In addition, the colleagues involved in this work participate in an in-house training program on patient-centred health information. © Georg Thieme Verlag KG Stuttgart · New York.

Integrating biological and social values when prioritizing places for biodiversity conservation.

PubMed

Whitehead, Amy L; Kujala, Heini; Ives, Christopher D; Gordon, Ascelin; Lentini, Pia E; Wintle, Brendan A; Nicholson, Emily; Raymond, Christopher M

2014-08-01

The consideration of information on social values in conjunction with biological data is critical for achieving both socially acceptable and scientifically defensible conservation planning outcomes. However, the influence of social values on spatial conservation priorities has received limited attention and is poorly understood. We present an approach that incorporates quantitative data on social values for conservation and social preferences for development into spatial conservation planning. We undertook a public participation GIS survey to spatially represent social values and development preferences and used species distribution models for 7 threatened fauna species to represent biological values. These spatially explicit data were simultaneously included in the conservation planning software Zonation to examine how conservation priorities changed with the inclusion of social data. Integrating spatially explicit information about social values and development preferences with biological data produced prioritizations that differed spatially from the solution based on only biological data. However, the integrated solutions protected a similar proportion of the species' distributions, indicating that Zonation effectively combined the biological and social data to produce socially feasible conservation solutions of approximately equivalent biological value. We were able to identify areas of the landscape where synergies and conflicts between different value sets are likely to occur. Identification of these synergies and conflicts will allow decision makers to target communication strategies to specific areas and ensure effective community engagement and positive conservation outcomes. © 2014 Society for Conservation Biology.

Human health and wellbeing in environmental impact assessment in New South Wales, Australia: Auditing health impacts within environmental assessments of major projects

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

Harris, Patrick J., E-mail: patrick.harris@unsw.edu.a; Harris, Elizabeth, E-mail: e.harris@unsw.edu.a; Thompson, Susan, E-mail: s.thompson@unsw.edu.a

Internationally the inclusion of health within environmental impact assessment (EIA) has been shown to be limited. While Australian EIA documentation has not been studied empirically to date, deficiencies in practice have been documented. This research developed an audit tool to undertake a qualitative descriptive analysis of 22 Major Project EAs in New South Wales, Australia. Results showed that health and wellbeing impacts were not considered explicitly. They were, however, included indirectly in the identification of traditional public health exposures associated with the physical environment and to a lesser extent the inclusion of social and economic impacts. However, no health datamore » was used to inform any of the assessments, there was no reference to causal pathways between exposures or determinants and physical or mental health effects, and there was no inclusion of the differential distribution of exposures or health impacts on different populations. The results add conceptually and practically to the long standing integration debate, showing that health is in a position to add value to the EIA process as an explicit part of standard environmental, social and economic considerations. However, to overcome the consistently documented barriers to integrating health in EIA, capacity must be developed amongst EIA professionals, led by the health sector, to progress health related knowledge and tools.« less

Measuring Explicit Word Learning of Preschool Children: A Development Study.

PubMed

Kelley, Elizabeth Spencer

2017-08-15

The purpose of this article is to present preliminary results related to the development of a new measure of explicit word learning. The measure incorporated elements of explicit vocabulary instruction and dynamic assessment and was designed to be sensitive to differences in word learning skill and to be feasible for use in clinical settings. The explicit word learning measure included brief teaching trials and repeated fine-grained measurement of semantic knowledge and production of 3 novel words (2 verbs and 1 adjective). Preschool children (N = 23) completed the measure of explicit word learning; standardized, norm-referenced measures of expressive and receptive vocabulary; and an incidental word learning task. The measure of explicit word learning provided meaningful information about word learning. Performance on the explicit measure was related to existing vocabulary knowledge and incidental word learning. Findings from this development study indicate that further examination of the measure of explicit word learning is warranted. The measure may have the potential to identify children who are poor word learners. https://doi.org/10.23641/asha.5170738.

The predictive effect of empathy and social norms on adolescents' implicit and explicit stigma responses.

PubMed

Silke, Charlotte; Swords, Lorraine; Heary, Caroline

2017-11-01

Research indicates that adolescents who experience mental health difficulties are frequently stigmatised by their peers. Stigmatisation is associated with a host of negative social and psychological effects, which impacts a young person's well-being. As a result, the development of effective anti-stigma strategies is considered a major research priority. However, in order to design effective stigma reduction strategies, researchers must be informed by an understanding of the factors that influence the expression of stigma. Although evidence suggests that empathy and social norms have a considerable effect on adolescents' social attitudes and behaviours, research has yet to examine whether these factors significantly influence adolescents' responses toward their peers with mental health difficulties. Thus, this study aims to examine whether empathy (cognitive and affective) and peer norms (descriptive and injunctive) influence adolescents' implicit and explicit stigmatising responses toward peers with mental health problems. A total of 570 (221 male and 348 female; 1 non-specified) adolescents, aged between 13 and 18 years (M = 15.51, SD = 1.13), participated in this research. Adolescents read vignettes describing male/female depressed and 'typically developing' peers. Adolescents answered questions assessing their stigmatising responses toward each target, as well as their empathic responding and normative perceptions. A sub-sample of participants (n=173) also completed an IAT assessing their implicit stigmatising responses. Results showed that descriptive norms exerted a substantial effect on adolescents' explicit responses. Cognitive empathy, affective empathy and injunctive norms exerted more limited effects on explicit responses. No significant effects were observed for implicit stigma. Overall, empathy was found to have limited effects on adolescents' explicit and implicit stigmatising responses, which may suggest that other contextual variables moderate the effects of dispositional empathy on responding. In conclusion, these findings suggest that tackling the perception of negative descriptive norms may be an effective strategy for reducing explicit stigmatising responses among adolescents. Copyright © 2017 Elsevier B.V. All rights reserved.

Thinking Together: Modeling Clinical Decision-Support as a Sociotechnical System

PubMed Central

Hussain, Mustafa I.; Reynolds, Tera L.; Mousavi, Fatemeh E.; Chen, Yunan; Zheng, Kai

2017-01-01

Computerized clinical decision-support systems are members of larger sociotechnical systems, composed of human and automated actors, who send, receive, and manipulate artifacts. Sociotechnical consideration is rare in the literature. This makes it difficult to comparatively evaluate the success of CDS implementations, and it may also indicate that sociotechnical context receives inadequate consideration in practice. To facilitate sociotechnical consideration, we developed the Thinking Together model, a flexible diagrammatical means of representing CDS systems as sociotechnical systems. To develop this model, we examined the literature with the lens of Distributed Cognition (DCog) theory. We then present two case studies of vastly different CDSSs, one almost fully automated and the other with minimal automation, to illustrate the flexibility of the Thinking Together model. We show that this model, informed by DCog and the CDS literature, are capable of supporting both research, by enabling comparative evaluation, and practice, by facilitating explicit sociotechnical planning and communication. PMID:29854164

Modeling trends from North American Breeding Bird Survey data: a spatially explicit approach

USGS Publications Warehouse

Bled, Florent; Sauer, John R.; Pardieck, Keith L.; Doherty, Paul; Royle, J. Andy

2013-01-01

Population trends, defined as interval-specific proportional changes in population size, are often used to help identify species of conservation interest. Efficient modeling of such trends depends on the consideration of the correlation of population changes with key spatial and environmental covariates. This can provide insights into causal mechanisms and allow spatially explicit summaries at scales that are of interest to management agencies. We expand the hierarchical modeling framework used in the North American Breeding Bird Survey (BBS) by developing a spatially explicit model of temporal trend using a conditional autoregressive (CAR) model. By adopting a formal spatial model for abundance, we produce spatially explicit abundance and trend estimates. Analyses based on large-scale geographic strata such as Bird Conservation Regions (BCR) can suffer from basic imbalances in spatial sampling. Our approach addresses this issue by providing an explicit weighting based on the fundamental sample allocation unit of the BBS. We applied the spatial model to three species from the BBS. Species have been chosen based upon their well-known population change patterns, which allows us to evaluate the quality of our model and the biological meaning of our estimates. We also compare our results with the ones obtained for BCRs using a nonspatial hierarchical model (Sauer and Link 2011). Globally, estimates for mean trends are consistent between the two approaches but spatial estimates provide much more precise trend estimates in regions on the edges of species ranges that were poorly estimated in non-spatial analyses. Incorporating a spatial component in the analysis not only allows us to obtain relevant and biologically meaningful estimates for population trends, but also enables us to provide a flexible framework in order to obtain trend estimates for any area.

Implicit and Explicit Number-Space Associations Differentially Relate to Interference Control in Young Adults With ADHD

PubMed Central

Georges, Carrie; Hoffmann, Danielle; Schiltz, Christine

2018-01-01

Behavioral evidence for the link between numerical and spatial representations comes from the spatial-numerical association of response codes (SNARC) effect, consisting in faster reaction times to small/large numbers with the left/right hand respectively. The SNARC effect is, however, characterized by considerable intra- and inter-individual variability. It depends not only on the explicit or implicit nature of the numerical task, but also relates to interference control. To determine whether the prevalence of the latter relation in the elderly could be ascribed to younger individuals’ ceiling performances on executive control tasks, we determined whether the SNARC effect related to Stroop and/or Flanker effects in 26 young adults with ADHD. We observed a divergent pattern of correlation depending on the type of numerical task used to assess the SNARC effect and the type of interference control measure involved in number-space associations. Namely, stronger number-space associations during parity judgments involving implicit magnitude processing related to weaker interference control in the Stroop but not Flanker task. Conversely, stronger number-space associations during explicit magnitude classifications tended to be associated with better interference control in the Flanker but not Stroop paradigm. The association of stronger parity and magnitude SNARC effects with weaker and better interference control respectively indicates that different mechanisms underlie these relations. Activation of the magnitude-associated spatial code is irrelevant and potentially interferes with parity judgments, but in contrast assists explicit magnitude classifications. Altogether, the present study confirms the contribution of interference control to number-space associations also in young adults. It suggests that magnitude-associated spatial codes in implicit and explicit tasks are monitored by different interference control mechanisms, thereby explaining task-related intra-individual differences in number-space associations. PMID:29881363

Progressive Damage Analysis of Bonded Composite Joints

NASA Technical Reports Server (NTRS)

Leone, Frank A., Jr.; Girolamo, Donato; Davila, Carlos G.

2012-01-01

The present work is related to the development and application of progressive damage modeling techniques to bonded joint technology. The joint designs studied in this work include a conventional composite splice joint and a NASA-patented durable redundant joint. Both designs involve honeycomb sandwich structures with carbon/epoxy facesheets joined using adhesively bonded doublers.Progressive damage modeling allows for the prediction of the initiation and evolution of damage within a structure. For structures that include multiple material systems, such as the joint designs under consideration, the number of potential failure mechanisms that must be accounted for drastically increases the complexity of the analyses. Potential failure mechanisms include fiber fracture, intraply matrix cracking, delamination, core crushing, adhesive failure, and their interactions. The bonded joints were modeled using highly parametric, explicitly solved finite element models, with damage modeling implemented via custom user-written subroutines. Each ply was discretely meshed using three-dimensional solid elements. Layers of cohesive elements were included between each ply to account for the possibility of delaminations and were used to model the adhesive layers forming the joint. Good correlation with experimental results was achieved both in terms of load-displacement history and the predicted failure mechanism(s).

Estimating the Health Effects of Greenhouse Gas Mitigation Strategies: Addressing Parametric, Model, and Valuation Challenges

PubMed Central

Hess, Jeremy J.; Ebi, Kristie L.; Markandya, Anil; Balbus, John M.; Wilkinson, Paul; Haines, Andy; Chalabi, Zaid

2014-01-01

Background: Policy decisions regarding climate change mitigation are increasingly incorporating the beneficial and adverse health impacts of greenhouse gas emission reduction strategies. Studies of such co-benefits and co-harms involve modeling approaches requiring a range of analytic decisions that affect the model output. Objective: Our objective was to assess analytic decisions regarding model framework, structure, choice of parameters, and handling of uncertainty when modeling health co-benefits, and to make recommendations for improvements that could increase policy uptake. Methods: We describe the assumptions and analytic decisions underlying models of mitigation co-benefits, examining their effects on modeling outputs, and consider tools for quantifying uncertainty. Discussion: There is considerable variation in approaches to valuation metrics, discounting methods, uncertainty characterization and propagation, and assessment of low-probability/high-impact events. There is also variable inclusion of adverse impacts of mitigation policies, and limited extension of modeling domains to include implementation considerations. Going forward, co-benefits modeling efforts should be carried out in collaboration with policy makers; these efforts should include the full range of positive and negative impacts and critical uncertainties, as well as a range of discount rates, and should explicitly characterize uncertainty. We make recommendations to improve the rigor and consistency of modeling of health co-benefits. Conclusion: Modeling health co-benefits requires systematic consideration of the suitability of model assumptions, of what should be included and excluded from the model framework, and how uncertainty should be treated. Increased attention to these and other analytic decisions has the potential to increase the policy relevance and application of co-benefits modeling studies, potentially helping policy makers to maximize mitigation potential while simultaneously improving health. Citation: Remais JV, Hess JJ, Ebi KL, Markandya A, Balbus JM, Wilkinson P, Haines A, Chalabi Z. 2014. Estimating the health effects of greenhouse gas mitigation strategies: addressing parametric, model, and valuation challenges. Environ Health Perspect 122:447–455; http://dx.doi.org/10.1289/ehp.1306744 PMID:24583270

A Geographically Explicit Genetic Model of Worldwide Human-Settlement History

PubMed Central

Liu, Hua; Prugnolle, Franck; Manica, Andrea; Balloux, François

2006-01-01

Currently available genetic and archaeological evidence is generally interpreted as supportive of a recent single origin of modern humans in East Africa. However, this is where the near consensus on human settlement history ends, and considerable uncertainty clouds any more detailed aspect of human colonization history. Here, we present a dynamic genetic model of human settlement history coupled with explicit geographical distances from East Africa, the likely origin of modern humans. We search for the best-supported parameter space by fitting our analytical prediction to genetic data that are based on 52 human populations analyzed at 783 autosomal microsatellite markers. This framework allows us to jointly estimate the key parameters of the expansion of modern humans. Our best estimates suggest an initial expansion of modern humans ∼56,000 years ago from a small founding population of ∼1,000 effective individuals. Our model further points to high growth rates in newly colonized habitats. The general fit of the model with the data is excellent. This suggests that coupling analytical genetic models with explicit demography and geography provides a powerful tool for making inferences on human-settlement history. PMID:16826514

Explicit continuous charge-based compact model for long channel heavily doped surrounding-gate MOSFETs incorporating interface traps and quantum effects

NASA Astrophysics Data System (ADS)

Hamzah, Afiq; Hamid, Fatimah A.; Ismail, Razali

2016-12-01

An explicit solution for long-channel surrounding-gate (SRG) MOSFETs is presented from intrinsic to heavily doped body including the effects of interface traps and fixed oxide charges. The solution is based on the core SRGMOSFETs model of the Unified Charge Control Model (UCCM) for heavily doped conditions. The UCCM model of highly doped SRGMOSFETs is derived to obtain the exact equivalent expression as in the undoped case. Taking advantage of the undoped explicit charge-based expression, the asymptotic limits for below threshold and above threshold have been redefined to include the effect of trap states for heavily doped cases. After solving the asymptotic limits, an explicit mobile charge expression is obtained which includes the trap state effects. The explicit mobile charge model shows very good agreement with respect to numerical simulation over practical terminal voltages, doping concentration, geometry effects, and trap state effects due to the fixed oxide charges and interface traps. Then, the drain current is obtained using the Pao-Sah's dual integral, which is expressed as a function of inversion charge densities at the source/drain ends. The drain current agreed well with the implicit solution and numerical simulation for all regions of operation without employing any empirical parameters. A comparison with previous explicit models has been conducted to verify the competency of the proposed model with the doping concentration of 1× {10}19 {{cm}}-3, as the proposed model has better advantages in terms of its simplicity and accuracy at a higher doping concentration.

Process Modeling Applied to Metal Forming and Thermomechanical Processing

DTIC Science & Technology

1984-09-01

the flow stress of structural alloys de- creases with temperature. It is well accepted that the homologous temperature, the ratio of the absolute...hardening coefficient y reducing to the value y = 1. This is simply the well - known Considere condition. The influence of strain rate sensitivity on...obtained by sent, well understood [6]. It is also important to note that no way rate effects explicitly in the Hill theory. Thus, comparisons of the

Ballistic Missile Defense in the European Theater: Political, Military and Technical Considerations

DTIC Science & Technology

2007-04-15

currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) 15 04 2007 2. REPORT TYPE...the European Security Strategy. These strategic documents implicitly and explicitly build a strong case for bolstering missile defense capabilities...states. The NMS advocates the building of a defense in depth by extending defensive capabilities well beyond United States borders, and uses the

Sending Nudes: Sex, Self-Rated Mate Value, and Trait Machiavellianism Predict Sending Unsolicited Explicit Images

PubMed Central

March, Evita; Wagstaff, Danielle L.

2017-01-01

Modern dating platforms have given rise to new dating and sexual behaviors. In the current study, we examine predictors of sending unsolicited explicit images, a particularly underexplored online sexual behavior. The aim of the current study was to explore the utility of dark personality traits (i.e., narcissism, Machiavellianism, psychopathy, and sadism) and self-rated mate value in predicting attitudes toward and behavior of sending unsolicited explicit images. Two hundred and forty participants (72% female; Mage = 25.96, SD = 9.79) completed an online questionnaire which included a measure of self-rated mate value, a measure of dark personality traits, and questions regarding sending unsolicited explicit images (operationalized as the explicit image scale). Men, compared to women, were found to have higher explicit image scale scores, and both self-rated mate value and trait Machiavellianism were positive predictors of explicit image scale scores. Interestingly, there were no significant interactions between sex and these variables. Further, Machiavellianism mediated all relationships between other dark traits and explicit image scale scores, indicating this behavior is best explained by the personality trait associated with behavioral strategies. In sum, these results provide support for the premise that sending unsolicited explicit images may be a tactic of a short-term mating strategy; however, future research should further explore this claim. PMID:29326632

Improving the quality of health care in the United Kingdom and the United States: a framework for change.

PubMed

Ferlie, E B; Shortell, S M

2001-01-01

Fueled by public incidents and growing evidence of deficiencies in care, concern over the quality and outcomes of care has increased in both the United Kingdom and the United States. Both countries have launched a number of initiatives to deal with these issues. These initiatives are unlikely to achieve their objectives without explicit consideration of the multilevel approach to change that includes the individual, group/team, organization, and larger environment/system level. Attention must be given to issues of leadership, culture, team development, and information technology at all levels. A number of contingent factors influence these efforts in both countries, which must each balance a number of tradeoffs between centralization and decentralization in efforts to sustain the impetus for quality improvement over time. The multilevel change framework and associated properties provide a framework for assessing progress along the journey.

Entropy of black holes with multiple horizons

NASA Astrophysics Data System (ADS)

He, Yun; Ma, Meng-Sen; Zhao, Ren

2018-05-01

We examine the entropy of black holes in de Sitter space and black holes surrounded by quintessence. These black holes have multiple horizons, including at least the black hole event horizon and a horizon outside it (cosmological horizon for de Sitter black holes and "quintessence horizon" for the black holes surrounded by quintessence). Based on the consideration that the two horizons are not independent each other, we conjecture that the total entropy of these black holes should not be simply the sum of entropies of the two horizons, but should have an extra term coming from the correlations between the two horizons. Different from our previous works, in this paper we consider the cosmological constant as the variable and employ an effective method to derive the explicit form of the entropy. We also try to discuss the thermodynamic stabilities of these black holes according to the entropy and the effective temperature.

Continuum theories for fluid-particle flows: Some aspects of lift forces and turbulence

NASA Technical Reports Server (NTRS)

Mctigue, David F.; Givler, Richard C.; Nunziato, Jace W.

1988-01-01

A general framework is outlined for the modeling of fluid particle flows. The momentum exchange between the constituents embodies both lift and drag forces, constitutive equations for which can be made explicit with reference to known single particle analysis. Relevant results for lift are reviewed, and invariant representations are posed. The fluid and particle velocities and the particle volume fraction are then decomposed into mean and fluctuating parts to characterize turbulent motions, and the equations of motion are averaged. In addition to the Reynolds stresses, further correlations between concentration and velocity fluctuations appear. These can be identified with turbulent transport processes such as eddy diffusion of the particles. When the drag force is dominant, the classical convection dispersion model for turbulent transport of particles is recovered. When other interaction forces enter, particle segregation effects can arise. This is illustrated qualitatively by consideration of turbulent channel flow with lift effects included.

Enhancing the Student Experiment Experience: Visible Scientific Inquiry Through a Virtual Chemistry Laboratory

NASA Astrophysics Data System (ADS)

Donnelly, Dermot; O'Reilly, John; McGarr, Oliver

2013-08-01

Practical work is often noted as a core reason many students take on science in secondary schools (high schools). However, there are inherent difficulties associated with classroom practical work that militate against scientific inquiry, an approach espoused by many science educators. The use of interactive simulations to facilitate student inquiry has emerged as a complement to practical work. This study presents case studies of four science teachers using a virtual chemistry laboratory (VCL) with their students in an explicitly guided inquiry manner. Research tools included the use of the Inquiry Science Implementation Scale in a `talk-aloud' manner, Reformed Teaching Observation Protocol for video observations, and teacher interviews. The findings suggest key aspects of practical work that hinder teachers in adequately supporting inquiry and highlight where a VCL can overcome many of these difficulties. The findings also indicate considerations in using the VCL in its own right.

Value-driven process management: using value to improve processes.

PubMed

Melnyk, S A; Christensen, R T

2000-08-01

Every firm can be viewed as consisting of various processes. These processes affect everything that the firm does from accepting orders and designing products to scheduling production. In many firms, the management of processes often reflects considerations of efficiency (cost) rather than effectiveness (value). In this article, we introduce a well-structured process for managing processes that begins not with the process, but rather with the customer and the product and the concept of value. This process progresses through a number of steps which include issues such as defining value, generating the appropriate metrics, identifying the critical processes, mapping and assessing the performance of these processes, and identifying long- and short-term areas for action. What makes the approach presented in this article so powerful is that it explicitly links the customer to the process and that the process is evaluated in term of its ability to effectively serve the customers.

An improved Cauchy number approach for predicting the drag and reconfiguration of flexible vegetation

NASA Astrophysics Data System (ADS)

Whittaker, Peter; Wilson, Catherine A. M. E.; Aberle, Jochen

2015-09-01

An improved model to describe the drag and reconfiguration of flexible riparian vegetation is proposed. The key improvement over previous models is the use of a refined 'vegetative' Cauchy number to explicitly determine the magnitude and rate of the vegetation's reconfiguration. After being derived from dimensional consideration, the model is applied to two experimental data sets. The first contains high-resolution drag force and physical property measurements for twenty-one foliated and defoliated full-scale trees, including specimens of Alnus glutinosa, Populus nigra and Salix alba. The second data set is independent and of a different scale, consisting of drag force and physical property measurements for natural and artificial branches of willow and poplar, under partially and fully submerged flow conditions. Good agreement between the measured and predicted drag forces is observed for both data sets, especially when compared to a more typical 'rigid' approximation, where the effects of reconfiguration are neglected.

Initialization and Predictability of a Coupled ENSO Forecast Model

NASA Technical Reports Server (NTRS)

Chen, Dake; Zebiak, Stephen E.; Cane, Mark A.; Busalacchi, Antonio J.

1997-01-01

The skill of a coupled ocean-atmosphere model in predicting ENSO has recently been improved using a new initialization procedure in which initial conditions are obtained from the coupled model, nudged toward observations of wind stress. The previous procedure involved direct insertion of wind stress observations, ignoring model feedback from ocean to atmosphere. The success of the new scheme is attributed to its explicit consideration of ocean-atmosphere coupling and the associated reduction of "initialization shock" and random noise. The so-called spring predictability barrier is eliminated, suggesting that such a barrier is not intrinsic to the real climate system. Initial attempts to generalize the nudging procedure to include SST were not successful; possible explanations are offered. In all experiments forecast skill is found to be much higher for the 1980s than for the 1970s and 1990s, suggesting decadal variations in predictability.

Mono- and Di-Alkylation Processes of DNA Bases by Nitrogen Mustard Mechlorethamine.

PubMed

Larrañaga, Olatz; de Cózar, Abel; Cossío, Fernando P

2017-12-06

The reactivity of nitrogen mustard mechlorethamine (mec) with purine bases towards formation of mono- (G-mec and A-mec) and dialkylated (AA-mec, GG-mec and AG-mec) adducts has been studied using density functional theory (DFT). To gain a complete overview of DNA-alkylation processes, direct chloride substitution and formation through activated aziridinium species were considered as possible reaction paths for adduct formation. Our results confirm that DNA alkylation by mec occurs via aziridine intermediates instead of direct substitution. Consideration of explicit water molecules in conjunction with polarizable continuum model (PCM) was shown as an adequate computational method for a proper representation of the system. Moreover, Runge-Kutta numerical kinetic simulations including the possible bisadducts have been performed. These simulations predicted a product ratio of 83:17 of GG-mec and AG-mec diadducts, respectively. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Unifying Views of Autism Spectrum Disorders: A Consideration of Autoregulatory Feedback Loops

PubMed Central

Mullins, Caitlin; Fishell, Gord

2017-01-01

Understanding the mechanisms underlying autism spectrum disorders (ASD) is a challenging goal. Here we review recent progress on several fronts, including genetics, proteomics, biochemistry and electrophysiology, that raise motivation for forming a viable pathophysiological hypothesis. In place of a traditionally unidirectional progression, we put forward a framework that extends homeostatic hypotheses by explicitly emphasizing autoregulatory feedback loops and known synaptic biology. The regulated biological feature can be neuronal electrical activity, the collective strength of synapses onto a dendritic branch, the local concentration of a signaling molecule, or the relative strengths of synaptic excitation and inhibition. The sensor of the biological variable (which we have termed the homeostat) engages mechanisms that operate as negative feedback elements to keep the biological variable tightly confined. We categorize known ASD-associated gene products according to their roles in such feedback loops, and provide detailed commentary for exemplar genes within each module. PMID:26985722

Plumbing noise in multifamily dwellings: 50 years and counting

NASA Astrophysics Data System (ADS)

Loverde, John J.; Dong, David W.

2005-09-01

Historically, plumbing sound was only of concern in luxury buildings and plumbing noise was rarely addressed explicitly in building codes or design guidelines. The last couple of decades have seen marked increases in population density, occupant expectations and sensitivity to noise, and the number of noise-related lawsuits. These demographic factors have considerably increased the importance of adequately addressing plumbing noise in multifamily projects, as shown by the increasing number of published guidelines (such as in the latest ASHRAE Handbook). Over the course of our firm's history, we have attempted to determine the relationship between the sound level from plumbing systems and the acceptability to the occupants. Our current criteria for plumbing noise and the reasoning behind them is discussed, including test cases and lawsuits, as well as the materials and methods available to meet those criteria, and their impact on the design of multifamily projects.

Science and policy: valuing framing, language and listening.

PubMed

Forbes, Stephen

2011-01-01

This paper considers the context for science contributing to policy development and explores some critical issues that should inform science advocacy and influence with policy makers. The paper argues that the key challenges are at least as much in educating conservation scientists and science communicators about society and policy making as they are in educating society and policy makers about science. The importance of developing processes to ensure that scientists and science communicators invest in the development of relationships based on respect and understanding of their audience in both communities and amongst policy makers provides a critical first step. The objectives of the Global Strategy for Plant Conservation acknowledge the importance of developing the capacities and public engagement necessary to implement the Strategy, including knowledge transfer and community capacity building. However, the development of targets to equip institutions and plant conservation professionals to explicitly address the barriers to influencing policy development through knowledge transfer and integration require further consideration.

Program optimizations: The interplay between power, performance, and energy

DOE PAGES

Leon, Edgar A.; Karlin, Ian; Grant, Ryan E.; ...

2016-05-16

Practical considerations for future supercomputer designs will impose limits on both instantaneous power consumption and total energy consumption. Working within these constraints while providing the maximum possible performance, application developers will need to optimize their code for speed alongside power and energy concerns. This paper analyzes the effectiveness of several code optimizations including loop fusion, data structure transformations, and global allocations. A per component measurement and analysis of different architectures is performed, enabling the examination of code optimizations on different compute subsystems. Using an explicit hydrodynamics proxy application from the U.S. Department of Energy, LULESH, we show how code optimizationsmore » impact different computational phases of the simulation. This provides insight for simulation developers into the best optimizations to use during particular simulation compute phases when optimizing code for future supercomputing platforms. Here, we examine and contrast both x86 and Blue Gene architectures with respect to these optimizations.« less

Extreme Basicity of Biguanide Drugs in Aqueous Solutions: Ion Transfer Voltammetry and DFT Calculations.

PubMed

Langmaier, Jan; Pižl, Martin; Samec, Zdeněk; Záliš, Stanislav

2016-09-22

Ion transfer voltammetry is used to estimate the acid dissociation constants Ka1 and Ka2 of the mono- and diprotonated forms of the biguanide drugs metformin (MF), phenformin (PF), and 1-phenylbiguanide (PB) in an aqueous solution. Measurements gave the pKa1 values for MFH(+), PFH(+), and PBH(+) characterizing the basicity of MF, PF, and PB, which are significantly higher than those reported in the literature. As a result, the monoprotonated forms of these biguanides should prevail in a considerably broader range of pH 1-15 (MFH(+), PFH(+)) and 2-13 (PBH(+)). DFT calculations with solvent correction were performed for possible tautomeric forms of neutral, monoprotonated, and diprotonated species. Extreme basicity of all drugs is confirmed by DFT calculations of pKa1 for the most stable tautomers of the neutral and protonated forms with explicit water molecules in the first solvation sphere included.

Asymptotic Linear Spectral Statistics for Spiked Hermitian Random Matrices

NASA Astrophysics Data System (ADS)

Passemier, Damien; McKay, Matthew R.; Chen, Yang

2015-07-01

Using the Coulomb Fluid method, this paper derives central limit theorems (CLTs) for linear spectral statistics of three "spiked" Hermitian random matrix ensembles. These include Johnstone's spiked model (i.e., central Wishart with spiked correlation), non-central Wishart with rank-one non-centrality, and a related class of non-central matrices. For a generic linear statistic, we derive simple and explicit CLT expressions as the matrix dimensions grow large. For all three ensembles under consideration, we find that the primary effect of the spike is to introduce an correction term to the asymptotic mean of the linear spectral statistic, which we characterize with simple formulas. The utility of our proposed framework is demonstrated through application to three different linear statistics problems: the classical likelihood ratio test for a population covariance, the capacity analysis of multi-antenna wireless communication systems with a line-of-sight transmission path, and a classical multiple sample significance testing problem.

Explicit Instruction Elements in Core Reading Programs

ERIC Educational Resources Information Center

Child, Angela R.

2012-01-01

Classroom teachers are provided instructional recommendations for teaching reading from their adopted core reading programs (CRPs). Explicit instruction elements or what is also called instructional moves, including direct explanation, modeling, guided practice, independent practice, discussion, feedback, and monitoring, were examined within CRP…

Generalized Born Models of Macromolecular Solvation Effects

NASA Astrophysics Data System (ADS)

Bashford, Donald; Case, David A.

2000-10-01

It would often be useful in computer simulations to use a simple description of solvation effects, instead of explicitly representing the individual solvent molecules. Continuum dielectric models often work well in describing the thermodynamic aspects of aqueous solvation, and approximations to such models that avoid the need to solve the Poisson equation are attractive because of their computational efficiency. Here we give an overview of one such approximation, the generalized Born model, which is simple and fast enough to be used for molecular dynamics simulations of proteins and nucleic acids. We discuss its strengths and weaknesses, both for its fidelity to the underlying continuum model and for its ability to replace explicit consideration of solvent molecules in macromolecular simulations. We focus particularly on versions of the generalized Born model that have a pair-wise analytical form, and therefore fit most naturally into conventional molecular mechanics calculations.

GPU-accelerated simulations of isolated black holes

NASA Astrophysics Data System (ADS)

Lewis, Adam G. M.; Pfeiffer, Harald P.

2018-05-01

We present a port of the numerical relativity code SpEC which is capable of running on NVIDIA GPUs. Since this code must be maintained in parallel with SpEC itself, a primary design consideration is to perform as few explicit code changes as possible. We therefore rely on a hierarchy of automated porting strategies. At the highest level we use TLoops, a C++ library of our design, to automatically emit CUDA code equivalent to tensorial expressions written into C++ source using a syntax similar to analytic calculation. Next, we trace out and cache explicit matrix representations of the numerous linear transformations in the SpEC code, which allows these to be performed on the GPU using pre-existing matrix-multiplication libraries. We port the few remaining important modules by hand. In this paper we detail the specifics of our port, and present benchmarks of it simulating isolated black hole spacetimes on several generations of NVIDIA GPU.

An ab initio MO study on the hydrolysis of methyl chloride with explicit consideration of 13 water molecules

NASA Astrophysics Data System (ADS)

Yamataka, Hiroshi; Aida, Misako

1998-06-01

Ab initio MO calculations (HF/3-21G, HF/6-31G, HF/6-31+G* and MP2/6-31+G*) were carried out on the hydrolysis of CH 3Cl in which up to 13 water solvent molecules were explicitly considered. For n⩾3, three important stationary points ( cmp1, TS, and cmp2) were detected in the course of the reaction. The calculations for the n=13 system at the HF/6-31+G* level reproduced the experimental activation enthalpy and the secondary deuterium kinetic isotope effect. The two reacting bond lengths in the transition state are 1.975 Å (O-C) and 2.500 Å (C-Cl), and CH 3Cl is surrounded by 13 water molecules without any apparent vacant space. The proton transfer from the attacking water to the water cluster occurs after TS is reached.

Guidelines for appropriate care: the importance of empirical normative analysis.

PubMed

Berg, M; Meulen, R T; van den Burg, M

2001-01-01

The Royal Dutch Medical Association recently completed a research project aimed at investigating how guidelines for 'appropriate medical care' should be construed. The project took as a starting point that explicit attention should be given to ethical and political considerations in addition to data about costs and effectiveness. In the project, two research groups set out to design guidelines and cost-effectiveness analyses (CEAs) for two circumscribed medical areas (angina pectoris and major depression). Our third group was responsible for the normative analysis. We undertook an explorative, qualitative pilot study of the normative considerations that played a role in constructing the guidelines and CEAs, and simultaneously interviewed specialists about the normative considerations that guided their diagnostic and treatment decisions. Explicating normative considerations, we argue, is important democratically: the issues at stake should not be left to decision analysts and guideline developers to decide. Moreover, it is a necessary condition for a successful implementation of such tools: those who draw upon these tools will only accept them when they can recognize themselves in the considerations implied. Empirical normative analysis, we argue, is a crucial tool in developing guidelines for appropriate medical care.

A conceptual framework for evaluating data suitability for observational studies.

PubMed

Shang, Ning; Weng, Chunhua; Hripcsak, George

2017-09-08

To contribute a conceptual framework for evaluating data suitability to satisfy the research needs of observational studies. Suitability considerations were derived from a systematic literature review on researchers' common data needs in observational studies and a scoping review on frequent clinical database design considerations, and were harmonized to construct a suitability conceptual framework using a bottom-up approach. The relationships among the suitability categories are explored from the perspective of 4 facets of data: intrinsic, contextual, representational, and accessible. A web-based national survey of domain experts was conducted to validate the framework. Data suitability for observational studies hinges on the following key categories: Explicitness of Policy and Data Governance, Relevance, Availability of Descriptive Metadata and Provenance Documentation, Usability, and Quality. We describe 16 measures and 33 sub-measures. The survey uncovered the relevance of all categories, with a 5-point Likert importance score of 3.9 ± 1.0 for Explicitness of Policy and Data Governance, 4.1 ± 1.0 for Relevance, 3.9 ± 0.9 for Availability of Descriptive Metadata and Provenance Documentation, 4.2 ± 1.0 for Usability, and 4.0 ± 0.9 for Quality. The suitability framework evaluates a clinical data source's fitness for research use. Its construction reflects both researchers' points of view and data custodians' design features. The feedback from domain experts rated Usability, Relevance, and Quality categories as the most important considerations. © The Author 2017. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Legal liability in iatrogenic orbital injury.

PubMed

Svider, Peter F; Kovalerchik, Olga; Mauro, Andrew C; Baredes, Soly; Eloy, Jean Anderson

2013-09-01

In this study, we detailed factors governing legal outcomes in iatrogenic orbital injury, with the purpose of discussing strategies to minimize liability and enhance patient safety. Retrospective analysis. Jury verdict and settlement reports were searched from publically available federal and state court records using the Westlaw database (Thomson Reuters, New York, NY). After exclusion of nonrelevant cases, 20 cases of iatrogenic orbital injuries were examined for factors such as legal outcome, damages awarded, defendant specialty, alleged causes of malpractice, and patient demographic information. The majority (60.0%) of cases were resolved in the defendant's favor. Payment was considerable for the cases decided in support of the plaintiff, averaging $1.13 million. Out-of-court settlements averaged $1.78 million (range, $487,500-$3.9 million), whereas jury-awarded damages averaged $472,661 (range, $75,000-$763,214). Complications stemming from endoscopic sinus surgery were most common (50.0%). Diplopia was the most common medical complaint (50.0%), whereas permanent deficits and having to undergo additional surgery were each present in 65.0% of cases. The potential for permanent sequelae of iatrogenic orbital injury makes this complication susceptible to malpractice litigation. Otolaryngologists were the most common defendants. Although cases were resolved in the defendant's favor 60% of the time, payments made were considerable, averaging $1.13 million. Steps to minimize liability and improve patient safety include an informed consent process explicitly listing risks, including diplopia and blindness, and obtaining timely ophthalmology consultation when a complication is recognized. Copyright © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

Some Observations from Behavioral Economics for Consideration in Promoting Money Management among Those with Substance Use Disorders

PubMed Central

Chivers, Laura L.; Higgins, Stephen T.

2016-01-01

Background Behavioral economics research has revealed systematic biases in decision making that merit consideration in efforts to promote money management skills among those with substance use disorders (SUDs). Objectives The objective of this article was to briefly review the literature on five of those biases (i.e., hyperbolic delay discounting, defaults and preference for the status quo, loss aversion, mental accounting, and failure to account for opportunity cost) that may have particular relevance to the topic of money management. Methods Selected studies are reviewed to illustrate these biases and how they may relate to efforts to promote money management skills among those with substance use disorders. Studies were identified by searching PubMed using the terms “behavioral economics” and “substance use disorders”, reviewing bibliographies of published articles, and discussions with colleagues. Results Only one of these biases (i.e., hyperbolic delay discounting) has been investigated extensively among those with SUDs. Indeed, it has been found to be sufficiently prevalent among those with SUDs to be considered as a potential risk factor for those disorders and certainly merits careful consideration in efforts to improve money management skills in that population. There has been relatively little empirical research reported regarding the other biases among those with SUDs, although they appear to be sufficiently fundamental to human behavior and relevant to the topic of money management (e.g., loss aversion) to also merit consideration. There is precedent of effective leveraging of behavioral economics principles in treatment development for SUDs (e.g., contingency management), including at least one intervention that explicitly focuses on money management (i.e., advisor–teller money management therapy). Conclusions and Scientific Significance The consideration of the systematic biases in human decision making that have been revealed in behavioral economics research has the potential to enhance efforts to devise effective strategies for improving money management skills among those with SUDs. PMID:22211484

Some observations from behavioral economics for consideration in promoting money management among those with substance use disorders.

PubMed

Chivers, Laura L; Higgins, Stephen T

2012-01-01

Behavioral economics research has revealed systematic biases in decision making that merit consideration in efforts to promote money management skills among those with substance use disorders (SUDs). The objective of this article was to briefly review the literature on five of those biases (i.e., hyperbolic delay discounting, defaults and preference for the status quo, loss aversion, mental accounting, and failure to account for opportunity cost) that may have particular relevance to the topic of money management. Selected studies are reviewed to illustrate these biases and how they may relate to efforts to promote money management skills among those with substance use disorders. Studies were identified by searching PubMed using the terms "behavioral economics" and "substance use disorders", reviewing bibliographies of published articles, and discussions with colleagues. Only one of these biases (i.e., hyperbolic delay discounting) has been investigated extensively among those with SUDs. Indeed, it has been found to be sufficiently prevalent among those with SUDs to be considered as a potential risk factor for those disorders and certainly merits careful consideration in efforts to improve money management skills in that population. There has been relatively little empirical research reported regarding the other biases among those with SUDs, although they appear to be sufficiently fundamental to human behavior and relevant to the topic of money management (e.g., loss aversion) to also merit consideration. There is precedent of effective leveraging of behavioral economics principles in treatment development for SUDs (e.g., contingency management), including at least one intervention that explicitly focuses on money management (i.e., advisor-teller money management therapy). The consideration of the systematic biases in human decision making that have been revealed in behavioral economics research has the potential to enhance efforts to devise effective strategies for improving money management skills among those with SUDs.

Effects of reducing attentional resources on implicit and explicit memory after severe traumatic brain injury.

PubMed

Watt, S; Shores, E A; Kinoshita, S

1999-07-01

Implicit and explicit memory were examined in individuals with severe traumatic brain injury (TBI) under conditions of full and divided attention. Participants included 12 individuals with severe TBI and 12 matched controls. In Experiment 1, participants carried out an implicit test of word-stem completion and an explicit test of cued recall. Results demonstrated that TBI participants exhibited impaired explicit memory but preserved implicit memory. In Experiment 2, a significant reduction in the explicit memory performance of both TBI and control participants, as well as a significant decrease in the implicit memory performance of TBI participants, was achieved by reducing attentional resources at encoding. These results indicated that performance on an implicit task of word-stem completion may require the availability of additional attentional resources that are not preserved after severe TBI.

Multistate approaches in computational protein design

PubMed Central

Davey, James A; Chica, Roberto A

2012-01-01

Computational protein design (CPD) is a useful tool for protein engineers. It has been successfully applied towards the creation of proteins with increased thermostability, improved binding affinity, novel enzymatic activity, and altered ligand specificity. Traditionally, CPD calculations search and rank sequences using a single fixed protein backbone template in an approach referred to as single-state design (SSD). While SSD has enjoyed considerable success, certain design objectives require the explicit consideration of multiple conformational and/or chemical states. Cases where a “multistate” approach may be advantageous over the SSD approach include designing conformational changes into proteins, using native ensembles to mimic backbone flexibility, and designing ligand or oligomeric association specificities. These design objectives can be efficiently tackled using multistate design (MSD), an emerging methodology in CPD that considers any number of protein conformational or chemical states as inputs instead of a single protein backbone template, as in SSD. In this review article, recent examples of the successful design of a desired property into proteins using MSD are described. These studies employing MSD are divided into two categories—those that utilized multiple conformational states, and those that utilized multiple chemical states. In addition, the scoring of competing states during negative design is discussed as a current challenge for MSD. PMID:22811394

PRA and Risk Informed Analysis

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

Bernsen, Sidney A.; Simonen, Fredric A.; Balkey, Kenneth R.

2006-01-01

The Boiler and Pressure Vessel Code (BPVC) of the American Society of Mechanical Engineers (ASME) has introduced a risk based approach into Section XI that covers Rules for Inservice Inspection of Nuclear Power Plant Components. The risk based approach requires application of the probabilistic risk assessments (PRA). Because no industry consensus standard existed for PRAs, ASME has developed a standard to evaluate the quality level of an available PRA needed to support a given risk based application. The paper describes the PRA standard, Section XI application of PRAs, and plans for broader applications of PRAs to other ASME nuclear codesmore » and standards. The paper addresses several specific topics of interest to Section XI. Important consideration are special methods (surrogate components) used to overcome the lack of PRA treatments of passive components in PRAs. The approach allows calculations of conditional core damage probabilities both for component failures that cause initiating events and failures in standby systems that decrease the availability of these systems. The paper relates the explicit risk based methods of the new Section XI code cases to the implicit consideration of risk used in the development of Section XI. Other topics include the needed interactions of ISI engineers, plant operating staff, PRA specialists, and members of expert panels that review the risk based programs.« less

Receiver psychology turns 20: is it time for a broader approach?

PubMed Central

Miller, Cory T.; Bee, Mark A.

2013-01-01

Twenty years ago, a new conceptual paradigm known as ‘receiver psychology’ was introduced to explain the evolution of animal communication systems. This paradigm advanced the idea that psychological processes in the receiver's nervous system influence a signal's detectability, discriminability and memorability, and thereby serve as powerful sources of selection shaping signal design. While advancing our understanding of signal diversity, more recent studies make clear that receiver psychology, as a paradigm, has been structured too narrowly and does not incorporate many of the perceptual and cognitive processes of signal reception that operate between sensory transduction and a receiver's response. Consequently, the past two decades of research on receiver psychology have emphasized considerations of signal evolution but failed to ask key questions about the mechanisms of signal reception and their evolution. The primary aim of this essay is to advocate for a broader receiver psychology paradigm that more explicitly includes a research focus on receivers' psychological landscapes. We review recent experimental studies of hearing and sound communication to illustrate how considerations of several general perceptual and cognitive processes will facilitate future research on animal signalling systems. We also emphasize how a rigorous comparative approach to receiver psychology is critical to explicating the full range of perceptual and cognitive processes involved in receiving and responding to signals. PMID:24013277

Sexual and reproductive health care for adolescents: legal rights and policy challenges.

PubMed

English, Abigail

2007-12-01

Laws developed over the past half century have significantly improved adolescents' access to essential sexual and reproductive health care. These laws allow many adolescent minors to give their own consent, protect confidentiality, and provide financial support for the care. The consent requirements for adolescents to receive health care are contained primarily in state court decisions and in statutes known as "state minor consent laws," which are based on either the minor's status or the services sought. Confidentiality protections for adolescents' health information are contained in these minor consent laws, in the federal medical privacy regulations known as the "HIPAA Privacy Rule," and in state medical privacy laws. Other significant laws include statutes providing for the emancipation of minors, court decisions delineating the mature minor doctrine, regulations protecting adolescents' access to confidential family planning services in publicly funded programs, and court decisions interpreting the constitutional right of privacy. Special considerations apply to consent and confidentiality questions pertaining to family planning, contraception, and pregnancy-related care for minors. In addition to the explicit provisions of state minor consent laws, many of the most important considerations are articulated in court decisions based on the constitutional right of privacy and the confidentiality requirements that are part of the federal Title X Family Planning Program and Medicaid.

Coincident Extraction of Line Objects from Stereo Image Pairs.

DTIC Science & Technology

1983-09-01

4.4.3 Reconstruction of intersections 4.5 Final result processing 5. Presentation of the results 5.1 FIM image processing system 5.2 Extraction results in...image. To achieve this goal, the existing software system had to be modified and extended considerably. The following sections of this report will give...8000 pixels of each image without explicit loading of subimages could not yet be performed due to computer system software problems. m m n m -4- The

On 'the fear of death' as the primary anxiety: how and why Klein differs from Freud.

PubMed

Blass, Rachel B

2014-08-01

It is well known that Melanie Klein held the view that 'fear of death' is the primary source of anxiety and that her position is explicitly opposed to that of Sigmund Freud, who maintained that that fear cannot in any way or form be a source of anxiety. In a previous article on Freud's Inhibitions, Symptoms and Anxiety (Blass, 2013), the author argued that, counter to what is commonly portrayed in the literature, Freud's considerations for rejecting the fear of death as a source of anxiety were based on relational and experiential factors that are usually associated with Kleinian psychoanalysis. In light of this affinity of Freud with Klein a question arises as to the actual source of their differences in this context. The present paper offers an answer to this question. The author first presents some of her earlier findings on what led Freud to reject the fear of death as a source of anxiety and then turns to investigate Klein's considerations for accepting it. This takes us beyond her explicit statements on this matter and sheds new light on the relationship of her views regarding death and anxiety and those of Freud. In turn this deepens the understanding of the relationship of Freud and Klein's conceptualizations of the psyche and its internal object relations, pointing to both surprising common ground and foundational differences. Copyright © 2014 Institute of Psychoanalysis.

Explicit expressions for meromorphic solutions of autonomous nonlinear ordinary differential equations

NASA Astrophysics Data System (ADS)

Demina, Maria V.; Kudryashov, Nikolay A.

2011-03-01

Meromorphic solutions of autonomous nonlinear ordinary differential equations are studied. An algorithm for constructing meromorphic solutions in explicit form is presented. General expressions for meromorphic solutions (including rational, periodic, elliptic) are found for a wide class of autonomous nonlinear ordinary differential equations.

A Solution to the Cosmic Conundrum including Cosmological Constant and Dark Energy Problems

NASA Astrophysics Data System (ADS)

Singh, A.

2009-12-01

A comprehensive solution to the cosmic conundrum is presented that also resolves key paradoxes of quantum mechanics and relativity. A simple mathematical model, the Gravity Nullification model (GNM), is proposed that integrates the missing physics of the spontaneous relativistic conversion of mass to energy into the existing physics theories, specifically a simplified general theory of relativity. Mechanistic mathematical expressions are derived for a relativistic universe expansion, which predict both the observed linear Hubble expansion in the nearby universe and the accelerating expansion exhibited by the supernova observations. The integrated model addresses the key questions haunting physics and Big Bang cosmology. It also provides a fresh perspective on the misconceived birth and evolution of the universe, especially the creation and dissolution of matter. The proposed model eliminates singularities from existing models and the need for the incredible and unverifiable assumptions including the superluminous inflation scenario, multiple universes, multiple dimensions, Anthropic principle, and quantum gravity. GNM predicts the observed features of the universe without any explicit consideration of time as a governing parameter.

Assessing health impact assessment: multidisciplinary and international perspectives

PubMed Central

Krieger, N; Northridge, M; Gruskin, S; Quinn, M; Kriebel, D; Davey, S; Bassett, M; Rehkopf, D; Miller, C

2003-01-01

Health impact assessment (HIA) seeks to expand evaluation of policy and programmes in all sectors, both private and public, to include their impact on population health. While the idea that the public's health is affected by a broad array of social and economic policies is not new and dates back well over two centuries, what is new is the notion—increasingly adopted by major health institutions, such as the World Health Organisation (WHO) and the United Kingdom National Health Services (NHS)—that health should be an explicit consideration when evaluating all public policies. In this article, it is argued that while HIA has the potential to enhance recognition of societal determinants of health and of intersectoral responsibility for health, its pitfalls warrant critical attention. Greater clarity is required regarding criteria for initiating, conducting, and completing HIA, including rules pertaining to decision making, enforcement, compliance, plus paying for their conduct. Critical debate over the promise, process, and pitfalls of HIA needs to be informed by multiple disciplines and perspectives from diverse people and regions of the world. PMID:12933768

Paleobiology of a Neoproterozoic tidal flat/lagoonal complex: the Draken Conglomerate Formation, Spitsbergen.

PubMed

Knoll, A H; Swett, K; Mark, J

1991-01-01

Carbonates and rare shales of the ca 700-800 Ma old Draken Conglomerate Formation, northeastern Spitsbergen, preserve a record of environmental variation within a Neoproterozoic tidal flat/lagoon complex. Forty-two microfossil taxa have been recognized in Draken rocks, and of these, 39 can be characterized in terms of their paleoenvironmental distributions along a gradient from the supratidal zone to permanently submerged lagoons. Supratidal to subtidal trends include: increasing microbenthic diversity, increasing abundance and diversity of included allochthonous (presumably planktonic) elements, decreasing sheath thickness of mat-building organisms (with significant taphonomic consequences), and an increasing sediment/fossil ratio in fossiliferous rocks. Five principal and several minor biofacies can be distinguished. The paleoecological resolution obtainable in the Draken Conglomerate Formation rivals that achieved for most Phanerozoic fossil deposits. It documents the complexity and diversity of Proterozoic coastal ecosystems and indicates that both environment and taphonomy need to be taken into explicit consideration in attempts to understand evolutionary trends in early fossil record. Three species, Coniunctiophycus majorinum, Myxococcoides distola, and M. chlorelloidea, are described as new; Siphonophycus robustum, Siphonophycus septatum, and Gorgonisphaeridium maximum are proposed as new combinations.

Paleobiology of a Neoproterozoic tidal flat/lagoonal complex: the Draken Conglomerate Formation, Spitsbergen

NASA Technical Reports Server (NTRS)

Knoll, A. H.; Swett, K.; Mark, J.

1991-01-01

Carbonates and rare shales of the ca 700-800 Ma old Draken Conglomerate Formation, northeastern Spitsbergen, preserve a record of environmental variation within a Neoproterozoic tidal flat/lagoon complex. Forty-two microfossil taxa have been recognized in Draken rocks, and of these, 39 can be characterized in terms of their paleoenvironmental distributions along a gradient from the supratidal zone to permanently submerged lagoons. Supratidal to subtidal trends include: increasing microbenthic diversity, increasing abundance and diversity of included allochthonous (presumably planktonic) elements, decreasing sheath thickness of mat-building organisms (with significant taphonomic consequences), and an increasing sediment/fossil ratio in fossiliferous rocks. Five principal and several minor biofacies can be distinguished. The paleoecological resolution obtainable in the Draken Conglomerate Formation rivals that achieved for most Phanerozoic fossil deposits. It documents the complexity and diversity of Proterozoic coastal ecosystems and indicates that both environment and taphonomy need to be taken into explicit consideration in attempts to understand evolutionary trends in early fossil record. Three species, Coniunctiophycus majorinum, Myxococcoides distola, and M. chlorelloidea, are described as new; Siphonophycus robustum, Siphonophycus septatum, and Gorgonisphaeridium maximum are proposed as new combinations.

Researchers’ Perceptions of the Ethical Implications of Pharmacogenomics Research with Children

PubMed Central

Avard, D.; Silverstein, T.; Sillon, G.; Joly, Y.

2009-01-01

Background This paper presents the results of an exploratory qualitative study that assesses Canadian pediatric researchers’ perceptions of a pre-selected group of ethical issues raised by pharmacogenomics research with children. Methods As a pilot study, we conducted semi-structured telephone interviews with Canadian pediatric pharmacogenomic researchers. The interviews were guided by the following themes: (1) benefits and risks of inclusion, (2) the consent/assent process, and (3) the return of research results. Results Issues about assent, consent, risks and benefits, as well as the communication of results were addressed by the respondents. Some issues, such as the unique vulnerability of children, the long term privacy concerns associated with biobanking, additional core elements that need to be discussed and included in the consent/assent forms, as well as the challenges of communicating research results in a pediatric research were not explicitly identified by the respondents. Conclusion Further consideration should be given to address the ethical challenges of including children in pharmacogenomics research. This exploratory study indicates that further guidance is needed if children are to be protected and yet benefit from such research. PMID:19204423

At the nexus of fire, water and society

PubMed Central

2016-01-01

The societal risks of water scarcity and water-quality impairment have received considerable attention, evidenced by recent analyses of these topics by the 2030 Water Resources Group, the United Nations and the World Economic Forum. What are the effects of fire on the predicted water scarcity and declines in water quality? Drinking water supplies for humans, the emphasis of this exploration, are derived from several land cover types, including forests, grasslands and peatlands, which are vulnerable to fire. In the last two decades, fires have affected the water supply catchments of Denver (CO) and other southwestern US cities, and four major Australian cities including Sydney, Canberra, Adelaide and Melbourne. In the same time period, several, though not all, national, regional and global water assessments have included fire in evaluations of the risks that affect water supplies. The objective of this discussion is to explore the nexus of fire, water and society with the hope that a more explicit understanding of fire effects on water supplies will encourage the incorporation of fire into future assessments of water supplies, into the pyrogeography conceptual framework and into planning efforts directed at water resiliency. This article is part of the themed issue ‘The interaction of fire and mankind’. PMID:27216505

Potential impacts of global warming on water resources in southern California.

PubMed

Beuhler, M

2003-01-01

Global warming will have a significant impact on water resources within the 20 to 90-year planning period of many water projects. Arid and semi-arid regions such as Southern California are especially vulnerable to anticipated negative impacts of global warming on water resources. Long-range water facility planning must consider global climate change in the recommended mix of new facilities needed to meet future water requirements. The generally accepted impacts of global warming include temperature, rising sea levels, more frequent and severe floods and droughts, and a shift from snowfall to rain. Precipitation changes are more difficult to predict. For Southern California, these impacts will be especially severe on surface water supplies. Additionally, rising sea levels will exacerbate salt-water intrusion into freshwater and impact the quality of surface water supplies. Integrated water resources planning is emerging as a tool to develop water supplies and demand management strategies that are less vulnerable to the impacts of global warming. These tools include water conservation, conjunctive use of surface and groundwater and desalination of brackish water and possibly seawater. Additionally, planning for future water needs should include explicit consideration of the potential range of global warming impacts through techniques such as scenario planning.

Marginalized zero-altered models for longitudinal count data.

PubMed

Tabb, Loni Philip; Tchetgen, Eric J Tchetgen; Wellenius, Greg A; Coull, Brent A

2016-10-01

Count data often exhibit more zeros than predicted by common count distributions like the Poisson or negative binomial. In recent years, there has been considerable interest in methods for analyzing zero-inflated count data in longitudinal or other correlated data settings. A common approach has been to extend zero-inflated Poisson models to include random effects that account for correlation among observations. However, these models have been shown to have a few drawbacks, including interpretability of regression coefficients and numerical instability of fitting algorithms even when the data arise from the assumed model. To address these issues, we propose a model that parameterizes the marginal associations between the count outcome and the covariates as easily interpretable log relative rates, while including random effects to account for correlation among observations. One of the main advantages of this marginal model is that it allows a basis upon which we can directly compare the performance of standard methods that ignore zero inflation with that of a method that explicitly takes zero inflation into account. We present simulations of these various model formulations in terms of bias and variance estimation. Finally, we apply the proposed approach to analyze toxicological data of the effect of emissions on cardiac arrhythmias.

Marginalized zero-altered models for longitudinal count data

PubMed Central

Tabb, Loni Philip; Tchetgen, Eric J. Tchetgen; Wellenius, Greg A.; Coull, Brent A.

2015-01-01

Count data often exhibit more zeros than predicted by common count distributions like the Poisson or negative binomial. In recent years, there has been considerable interest in methods for analyzing zero-inflated count data in longitudinal or other correlated data settings. A common approach has been to extend zero-inflated Poisson models to include random effects that account for correlation among observations. However, these models have been shown to have a few drawbacks, including interpretability of regression coefficients and numerical instability of fitting algorithms even when the data arise from the assumed model. To address these issues, we propose a model that parameterizes the marginal associations between the count outcome and the covariates as easily interpretable log relative rates, while including random effects to account for correlation among observations. One of the main advantages of this marginal model is that it allows a basis upon which we can directly compare the performance of standard methods that ignore zero inflation with that of a method that explicitly takes zero inflation into account. We present simulations of these various model formulations in terms of bias and variance estimation. Finally, we apply the proposed approach to analyze toxicological data of the effect of emissions on cardiac arrhythmias. PMID:27867423

Cumulative environmental impacts and integrated coastal management: the case of Xiamen, China.

PubMed

Xue, Xiongzhi; Hong, Huasheng; Charles, Anthony T

2004-07-01

This paper examines the assessment of cumulative environmental impacts and the implementation of integrated coastal management within the harbour of Xiamen, China, an urban region in which the coastal zone is under increasing pressure as a result of very rapid economic growth. The first stage of analysis incorporates components of a cumulative effects assessment, including (a) identification of sources of environmental impacts, notably industrial expansion, port development, shipping, waste disposal, aquaculture and coastal construction, (b) selection of a set of valued ecosystem components, focusing on circulation and siltation, water quality, sediment, the benthic community, and mangrove forests, and (c) use of a set of key indicators to examine cumulative impacts arising from the aggregate of human activities. In the second stage of analysis, the paper describes and assesses the development of an institutional framework for integrated coastal management in Xiamen, one that combines policy and planning (including legislative and enforcement mechanisms) with scientific and monitoring mechanisms (including an innovative 'marine functional zoning' system). The paper concludes that the integrated coastal management framework in Xiamen has met all relevant requirements for 'integration' as laid out in the literature, and has explicitly incorporated consideration of cumulative impacts within its management and monitoring processes.

Including thermal disorder of hydrogen bonding to describe the vibrational circular dichroism spectrum of zwitterionic L-alanine in water.

PubMed

Orestes, Ednilsom; Bistafa, Carlos; Rivelino, Roberto; Canuto, Sylvio

2015-05-28

The vibrational circular dichroism (VCD) spectrum of l-alanine amino acid in aqueous solution in ambient conditions has been studied. The emphasis has been placed on the inclusion of the thermal disorder of the solute-solvent hydrogen bonds that characterize the aqueous solution condition. A combined and sequential use of molecular mechanics and quantum mechanics was adopted. To calculate the average VCD spectrum, the DFT B3LYP/6-311++G(d,p) level of calculation was employed, over one-hundred configurations composed of the solute plus all water molecules making hydrogen bonds with the solute. Simplified considerations including only four explicit solvent molecules and the polarizable continuum model were also made for comparison. Considering the large number of vibration frequencies with only limited experimental results a direct comparison is presented, when possible, and in addition a statistical analysis of the calculated values was performed. The results are found to be in line with the experiment, leading to the conclusion that including thermal disorder may improve the agreement of the vibrational frequencies with experimental results, but the thermal effects may be of greater value in the calculations of the rotational strengths.

Implicit and explicit weight bias in a national sample of 4,732 medical students: the medical student CHANGES study.

PubMed

Phelan, Sean M; Dovidio, John F; Puhl, Rebecca M; Burgess, Diana J; Nelson, David B; Yeazel, Mark W; Hardeman, Rachel; Perry, Sylvia; van Ryn, Michelle

2014-04-01

To examine the magnitude of explicit and implicit weight biases compared to biases against other groups; and identify student factors predicting bias in a large national sample of medical students. A web-based survey was completed by 4,732 1st year medical students from 49 medical schools as part of a longitudinal study of medical education. The survey included a validated measure of implicit weight bias, the implicit association test, and 2 measures of explicit bias: a feeling thermometer and the anti-fat attitudes test. A majority of students exhibited implicit (74%) and explicit (67%) weight bias. Implicit weight bias scores were comparable to reported bias against racial minorities. Explicit attitudes were more negative toward obese people than toward racial minorities, gays, lesbians, and poor people. In multivariate regression models, implicit and explicit weight bias was predicted by lower BMI, male sex, and non-Black race. Either implicit or explicit bias was also predicted by age, SES, country of birth, and specialty choice. Implicit and explicit weight bias is common among 1st year medical students, and varies across student factors. Future research should assess implications of biases and test interventions to reduce their impact. Copyright © 2013 The Obesity Society.

Individual-Based Spatially-Explicit Model of an Herbivore and Its Resource: The Effect of Habitat Reduction and Fragmentation

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

Kostova, T; Carlsen, T; Kercher, J

2002-06-17

We present an individual-based, spatially-explicit model of the dynamics of a small mammal and its resource. The life histories of each individual animal are modeled separately. The individuals can have the status of residents or wanderers and belong to behaviorally differing groups of juveniles or adults and males or females. Their territory defending and monogamous behavior is taken into consideration. The resource, green vegetation, grows depending on seasonal climatic characteristics and is diminished due to the herbivore's grazing. Other specifics such as a varying personal energetic level due to feeding and starvation of the individuals, mating preferences, avoidance of competitors,more » dispersal of juveniles, as a result of site overgrazing, etc. are included in the model. We determined model parameters from real data for the species Microtus ochrogaster (prairie vole). The simulations are done for a case of an enclosed habitat without predators or other species competitors. The goal of the study is to find the relation between size of habitat and population persistence. The experiments with the model show the populations go extinct due to severe overgrazing, but that the length of population persistence depends on the area of the habitat as well as on the presence of fragmentation. Additionally, the total population size of the vole population obtained during the simulations exhibits yearly fluctuations as well as multi-yearly peaks of fluctuations. This dynamics is similar to the one observed in prairie vole field studies.« less

Valuing flexibilities in the design of urban water management systems.

PubMed

Deng, Yinghan; Cardin, Michel-Alexandre; Babovic, Vladan; Santhanakrishnan, Deepak; Schmitter, Petra; Meshgi, Ali

2013-12-15

Climate change and rapid urbanization requires decision-makers to develop a long-term forward assessment on sustainable urban water management projects. This is further complicated by the difficulties of assessing sustainable designs and various design scenarios from an economic standpoint. A conventional valuation approach for urban water management projects, like Discounted Cash Flow (DCF) analysis, fails to incorporate uncertainties, such as amount of rainfall, unit cost of water, and other uncertainties associated with future changes in technological domains. Such approach also fails to include the value of flexibility, which enables managers to adapt and reconfigure systems over time as uncertainty unfolds. This work describes an integrated framework to value investments in urban water management systems under uncertainty. It also extends the conventional DCF analysis through explicit considerations of flexibility in systems design and management. The approach incorporates flexibility as intelligent decision-making mechanisms that enable systems to avoid future downside risks and increase opportunities for upside gains over a range of possible futures. A water catchment area in Singapore was chosen to assess the value of a flexible extension of standard drainage canals and a flexible deployment of a novel water catchment technology based on green roofs and porous pavements. Results show that integrating uncertainty and flexibility explicitly into the decision-making process can reduce initial capital expenditure, improve value for investment, and enable decision-makers to learn more about system requirements during the lifetime of the project. Copyright © 2013 Elsevier Ltd. All rights reserved.

The influence of explicit versus implicit instructional approaches during a technology-based curriculum on students' understanding of nature of science (NOS)

NASA Astrophysics Data System (ADS)

Al-Saidi, Ahmed Mohammad

The purpose of this study was to examine the effect of an explicit versus an implicit instructional approach during technology-based curriculum on students' understanding of the nature of science (NOS) within an introductory biology course. The study emphasized the inferential and tentative nature of science. The intervention or explicit group was involved in inquiry activities followed by discussions that were directly geared towards the target aspects of NOS. The implicit group was engaged in the same activities but received instruction devoid of direct reference to the NOS aspects. Students in both groups spent identical amount of time on task. Selected items of the Views of Nature of Science Questionnaire (VNOS) together with semi-structured interviews were used to evaluate students' NOS conceptions before and at the end of the intervention, which lasted two weeks. A quantitative analysis using chi-square of students' pre-intervention NOS views as provided by the VNOS questionnaires revealed that there was not a statistically significant difference between implicit and explicit groups in both targeted NOS aspects, with (p = 0.18) and (p = 0.34) for inferential and tentative NOS, respectively. However the same analysis indicated statistical significance difference for post-intervention between implicit and explicit groups, yielding (p < 0.02) and (p < 0.002) for both inferential and tentative NOS, respectively. A qualitative analysis of students' pre and post-intervention views of the target aspects of NOS as well as semi-structured interviews for both groups was also conducted. Before intervention, the number of informed NOS responses in both groups was not considerably different. However, analysis of post-intervention NOS views indicated that more students in the explicit group demonstrated informed views of the NOS aspects than in the implicit group. Therefore, the analysis of the data indicated that, in this particular study, engaging students in inquiry-based activities followed by explicit discussion that is geared toward NOS aspects was more effective than merely involving them in implicit, inquiry-based instruction. The imperative finding of the present study provides evidence that teaching the NOS could be achieved through short-intensive discussion and does not necessarily require separate and independent courses.

On ultrasound-induced microbubble oscillation in a capillary blood vessel and its implications for the blood-brain barrier

NASA Astrophysics Data System (ADS)

Wiedemair, W.; Tuković, Ž.; Jasak, H.; Poulikakos, D.; Kurtcuoglu, V.

2012-02-01

The complex interaction between an ultrasound-driven microbubble and an enclosing capillary microvessel is investigated by means of a coupled, multi-domain numerical model using the finite volume formulation. This system is of interest in the study of transient blood-brain barrier disruption (BBBD) for drug delivery applications. The compliant vessel structure is incorporated explicitly as a distinct domain described by a dedicated physical model. Red blood cells (RBCs) are taken into account as elastic solids in the blood plasma. We report the temporal and spatial development of transmural pressure (Ptm) and wall shear stress (WSS) at the luminal endothelial interface, both of which are candidates for the yet unknown mediator of BBBD. The explicit introduction of RBCs shapes the Ptm and WSS distributions and their derivatives markedly. While the peak values of these mechanical wall parameters are not affected considerably by the presence of RBCs, a pronounced increase in their spatial gradients is observed compared to a configuration with blood plasma alone. The novelty of our work lies in the explicit treatment of the vessel wall, and in the modelling of blood as a composite fluid, which we show to be relevant for the mechanical processes at the endothelium.

[Application of spatially explicit landscape model in soil loss study in Huzhong area].

PubMed

Xu, Chonggang; Hu, Yuanman; Chang, Yu; Li, Xiuzhen; Bu, Renchang; He, Hongshi; Leng, Wenfang

2004-10-01

Universal Soil Loss Equation (USLE) has been widely used to estimate the average annual soil loss. In most of the previous work on soil loss evaluation on forestland, cover management factor was calculated from the static forest landscape. The advent of spatially explicit forest landscape model in the last decade, which explicitly simulates the forest succession dynamics under natural and anthropogenic disturbances (fire, wind, harvest and so on) on heterogeneous landscape, makes it possible to take into consideration the change of forest cover, and to dynamically simulate the soil loss in different year (e.g. 10 years and 20 years after current year). In this study, we linked a spatially explicit landscape model (LANDIS) with USLE to simulate the soil loss dynamics under two scenarios: fire and no harvest, fire and harvest. We also simulated the soil loss with no fire and no harvest as a control. The results showed that soil loss varied periodically with simulation year, and the amplitude of change was the lowest under the control scenario and the highest under the fire and no harvest scenario. The effect of harvest on soil loss could not be easily identified on the map; however, the cumulative effect of harvest on soil loss was larger than that of fire. Decreasing the harvest area and the percent of bare soil increased by harvest could significantly reduce soil loss, but had no significant effects on the dynamic of soil loss. Although harvest increased the annual soil loss, it tended to decrease the variability of soil loss between different simulation years.

Implicit memory. Retention without remembering.

PubMed

Roediger, H L

1990-09-01

Explicit measures of human memory, such as recall or recognition, reflect conscious recollection of the past. Implicit tests of retention measure transfer (or priming) from past experience on tasks that do not require conscious recollection of recent experiences for their performance. The article reviews research on the relation between explicit and implicit memory. The evidence points to substantial differences between standard explicit and implicit tests, because many variables create dissociations between these tests. For example, although pictures are remembered better than words on explicit tests, words produce more priming than do pictures on several implicit tests. These dissociations may implicate different memory systems that subserve distinct memorial functions, but the present argument is that many dissociations can be understood by appealing to general principles that apply to both explicit and implicit tests. Phenomena studied under the rubric of implicit memory may have important implications in many other fields, including social cognition, problem solving, and cognitive development.

Darboux transformation and explicit solutions for some (2+1)-dimensional equations

NASA Astrophysics Data System (ADS)

Wang, Yan; Shen, Lijuan; Du, Dianlou

2007-06-01

Three systems of (2+1)-dimensional soliton equations and their decompositions into the (1+1)-dimensional soliton equations are proposed. These equations include KPI, CKP, MKPI. With the help of Darboux transformation of (1+1)-dimensional equations, we get the explicit solutions of the (2+1)-dimensional equations.

La parole, vue et prise par les etudiants (Speech as Seen and Understood by Student).

ERIC Educational Resources Information Center

Gajo, Laurent, Ed.; Jeanneret, Fabrice, Ed.

1998-01-01

Articles on speech and second language learning include: "Les sequences de correction en classe de langue seconde: evitement du 'non' explicite" ("Error Correction Sequences in Second Language Class: Avoidance of the Explicit 'No'") (Anne-Lise de Bosset); "Analyse hierarchique et fonctionnelle du discours: conversations…

An example of population-level risk assessments for small mammals using individual-based population models.

PubMed

Schmitt, Walter; Auteri, Domenica; Bastiansen, Finn; Ebeling, Markus; Liu, Chun; Luttik, Robert; Mastitsky, Sergey; Nacci, Diane; Topping, Chris; Wang, Magnus

2016-01-01

This article presents a case study demonstrating the application of 3 individual-based, spatially explicit population models (IBMs, also known as agent-based models) in ecological risk assessments to predict long-term effects of a pesticide to populations of small mammals. The 3 IBMs each used a hypothetical fungicide (FungicideX) in different scenarios: spraying in cereals (common vole, Microtus arvalis), spraying in orchards (field vole, Microtus agrestis), and cereal seed treatment (wood mouse, Apodemus sylvaticus). Each scenario used existing model landscapes, which differed greatly in size and structural complexity. The toxicological profile of FungicideX was defined so that the deterministic long-term first tier risk assessment would result in high risk to small mammals, thus providing the opportunity to use the IBMs for risk assessment refinement (i.e., higher tier risk assessment). Despite differing internal model design and scenarios, results indicated in all 3 cases low population sensitivity unless FungicideX was applied at very high (×10) rates. Recovery from local population impacts was generally fast. Only when patch extinctions occured in simulations of intentionally high acute toxic effects, recovery periods, then determined by recolonization, were of any concern. Conclusions include recommendations for the most important input considerations, including the selection of exposure levels, duration of simulations, statistically robust number of replicates, and endpoints to report. However, further investigation and agreement are needed to develop recommendations for landscape attributes such as size, structure, and crop rotation to define appropriate regulatory risk assessment scenarios. Overall, the application of IBMs provides multiple advantages to higher tier ecological risk assessments for small mammals, including consistent and transparent direct links to specific protection goals, and the consideration of more realistic scenarios. © 2015 SETAC.

Extending Vulnerability Assessment to Include Life Stages Considerations

PubMed Central

Hodgson, Emma E.; Essington, Timothy E.; Kaplan, Isaac C.

2016-01-01

Species are experiencing a suite of novel stressors from anthropogenic activities that have impacts at multiple scales. Vulnerability assessment is one tool to evaluate the likely impacts that these stressors pose to species so that high-vulnerability cases can be identified and prioritized for monitoring, protection, or mitigation. Commonly used semi-quantitative methods lack a framework to explicitly account for differences in exposure to stressors and organism responses across life stages. Here we propose a modification to commonly used spatial vulnerability assessment methods that includes such an approach, using ocean acidification in the California Current as an illustrative case study. Life stage considerations were included by assessing vulnerability of each life stage to ocean acidification and were used to estimate population vulnerability in two ways. We set population vulnerability equal to: (1) the maximum stage vulnerability and (2) a weighted mean across all stages, with weights calculated using Lefkovitch matrix models. Vulnerability was found to vary across life stages for the six species explored in this case study: two krill–Euphausia pacifica and Thysanoessa spinifera, pteropod–Limacina helicina, pink shrimp–Pandalus jordani, Dungeness crab–Metacarcinus magister and Pacific hake–Merluccius productus. The maximum vulnerability estimates ranged from larval to subadult and adult stages with no consistent stage having maximum vulnerability across species. Similarly, integrated vulnerability metrics varied greatly across species. A comparison showed that some species had vulnerabilities that were similar between the two metrics, while other species’ vulnerabilities varied substantially between the two metrics. These differences primarily resulted from cases where the most vulnerable stage had a low relative weight. We compare these methods and explore circumstances where each method may be appropriate. PMID:27416031

Extending Vulnerability Assessment to Include Life Stages Considerations.

PubMed

Hodgson, Emma E; Essington, Timothy E; Kaplan, Isaac C

2016-01-01

Species are experiencing a suite of novel stressors from anthropogenic activities that have impacts at multiple scales. Vulnerability assessment is one tool to evaluate the likely impacts that these stressors pose to species so that high-vulnerability cases can be identified and prioritized for monitoring, protection, or mitigation. Commonly used semi-quantitative methods lack a framework to explicitly account for differences in exposure to stressors and organism responses across life stages. Here we propose a modification to commonly used spatial vulnerability assessment methods that includes such an approach, using ocean acidification in the California Current as an illustrative case study. Life stage considerations were included by assessing vulnerability of each life stage to ocean acidification and were used to estimate population vulnerability in two ways. We set population vulnerability equal to: (1) the maximum stage vulnerability and (2) a weighted mean across all stages, with weights calculated using Lefkovitch matrix models. Vulnerability was found to vary across life stages for the six species explored in this case study: two krill-Euphausia pacifica and Thysanoessa spinifera, pteropod-Limacina helicina, pink shrimp-Pandalus jordani, Dungeness crab-Metacarcinus magister and Pacific hake-Merluccius productus. The maximum vulnerability estimates ranged from larval to subadult and adult stages with no consistent stage having maximum vulnerability across species. Similarly, integrated vulnerability metrics varied greatly across species. A comparison showed that some species had vulnerabilities that were similar between the two metrics, while other species' vulnerabilities varied substantially between the two metrics. These differences primarily resulted from cases where the most vulnerable stage had a low relative weight. We compare these methods and explore circumstances where each method may be appropriate.

Stakeholders apply the GRADE evidence-to-decision framework to facilitate coverage decisions.

PubMed

Dahm, Philipp; Oxman, Andrew D; Djulbegovic, Benjamin; Guyatt, Gordon H; Murad, M Hassan; Amato, Laura; Parmelli, Elena; Davoli, Marina; Morgan, Rebecca L; Mustafa, Reem A; Sultan, Shahnaz; Falck-Ytter, Yngve; Akl, Elie A; Schünemann, Holger J

2017-06-01

Coverage decisions are complex and require the consideration of many factors. A well-defined, transparent process could improve decision-making and facilitate decision-maker accountability. We surveyed key US-based stakeholders regarding their current approaches for coverage decisions. Then, we held a workshop to test an evidence-to-decision (EtD) framework for coverage based on the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria. A total of 42 individuals (including 19 US stakeholders as well as international health policymakers and GRADE working group members) attended the workshop. Of the 19 stakeholders, 14 (74%) completed the survey before the workshop. Almost all of their organizations (13 of 14; 93%) used systematic reviews for coverage decision-making; few (2 of 14; 14%) developed their own evidence synthesis; a majority (9 of 14; 64%) rated the certainty of evidence (using various systems); almost all (13 of 14; 93%) denied formal consideration of resource use; and half (7 of 14; 50%) reported explicit criteria for decision-making. At the workshop, stakeholders successfully applied the EtD framework to four case studies and provided narrative feedback, which centered on contextual factors affecting coverage decisions in the United States, the need for reliable data on subgroups of patients, and the challenge of decision-making without formal consideration of resource use. Stakeholders successfully applied the EtD framework to four case studies and highlighted contextual factors affecting coverage decisions and affirmed its value. Their input informed the further development of a revised EtD framework, now publicly available (http://gradepro.org/). Published by Elsevier Inc.

Public participation in decision-making on the coverage of new antivirals for hepatitis C.

PubMed

Kieslich, Katharina; Ahn, Jeonghoon; Badano, Gabriele; Chalkidou, Kalipso; Cubillos, Leonardo; Hauegen, Renata Curi; Henshall, Chris; Krubiner, Carleigh B; Littlejohns, Peter; Lu, Lanting; Pearson, Steven D; Rid, Annette; Whitty, Jennifer A; Wilson, James

2016-08-15

Purpose - New hepatitis C medicines such as sofosbuvir underline the need to balance considerations of innovation, clinical evidence, budget impact and equity in health priority-setting. The purpose of this paper is to examine the role of public participation in addressing these considerations. Design/methodology/approach - The paper employs a comparative case study approach. It explores the experience of four countries - Brazil, England, South Korea and the USA - in making coverage decisions about the antiviral sofosbuvir and involving the public and patients in these decision-making processes. Findings - Issues emerging from public participation ac tivities include the role of the universal right to health in Brazil, the balance between innovation and budget impact in England, the effect of unethical medical practices on public perception in South Korea and the legitimacy of priority-setting processes in the USA. Providing policymakers are receptive to these issues, public participation activities may be re-conceptualized as processes that illuminate policy problems relevant to a particular context, thereby promoting an agenda-setting role for the public. Originality/value - The paper offers an empirical analysis of public involvement in the case of sofosbuvir, where the relevant considerations that bear on priority-setting decisions have been particularly stark. The perspectives that emerge suggest that public participation contributes to raising attention to issues that need to be addressed by policymakers. Public participation activities can thus contribute to setting policy agendas, even if that is not their explicit purpose. However, the actualization of this contribution is contingent on the receptiveness of policymakers.

Exponential localization of Wannier functions in insulators.

PubMed

Brouder, Christian; Panati, Gianluca; Calandra, Matteo; Mourougane, Christophe; Marzari, Nicola

2007-01-26

The exponential localization of Wannier functions in two or three dimensions is proven for all insulators that display time-reversal symmetry, settling a long-standing conjecture. Our proof relies on the equivalence between the existence of analytic quasi-Bloch functions and the nullity of the Chern numbers (or of the Hall current) for the system under consideration. The same equivalence implies that Chern insulators cannot display exponentially localized Wannier functions. An explicit condition for the reality of the Wannier functions is identified.

Implications of a quadratic stream definition in radiative transfer theory.

NASA Technical Reports Server (NTRS)

Whitney, C.

1972-01-01

An explicit definition of the radiation-stream concept is stated and applied to approximate the integro-differential equation of radiative transfer with a set of twelve coupled differential equations. Computational efficiency is enhanced by distributing the corresponding streams in three-dimensional space in a totally symmetric way. Polarization is then incorporated in this model. A computer program based on the model is briefly compared with a Monte Carlo program for simulation of horizon scans of the earth's atmosphere. It is found to be considerably faster.

Constructing increment-decrement life tables.

PubMed

Schoen, R

1975-05-01

A life table model which can recognize increments (or entrants) as well as decrements has proven to be of considerable value in the analysis of marital status patterns, labor force participation patterns, and other areas of substantive interest. Nonetheless, relatively little work has been done on the methodology of increment-decrement (or combined) life tables. The present paper reviews the general, recursive solution of Schoen and Nelson (1974), develops explicit solutions for three cases of particular interest, and compares alternative approaches to the construction of increment-decrement tables.

Tailoring the Psychotherapy to the Borderline Patient

PubMed Central

HORWITZ, LEONARD; GABBARD, GLEN O.; ALLEN, JON G.; COLSON, DONALD B.; FRIESWYK, SIEBOLT; NEWSOM, GAVIN E.; COYNE, LOLAFAYE

1996-01-01

Views still differ as to the optimal psychodynamic treatment of borderline patients. Recommendations range from psychoanalysis and exploratory psychotherapy to an explicitly supportive treatment aimed at strengthening adaptive defenses. The authors contend that no single approach is appropriate for all patients in this wide-ranging diagnostic category, which spans a continuum from close-to-neurotic to close-to-psychotic levels of functioning. Careful differentiations based on developmental considerations, ego structures, and relationship patterns provide the basis for the optimal treatment approach. PMID:22700301

EdgeMaps: visualizing explicit and implicit relations

NASA Astrophysics Data System (ADS)

Dörk, Marian; Carpendale, Sheelagh; Williamson, Carey

2011-01-01

In this work, we introduce EdgeMaps as a new method for integrating the visualization of explicit and implicit data relations. Explicit relations are specific connections between entities already present in a given dataset, while implicit relations are derived from multidimensional data based on shared properties and similarity measures. Many datasets include both types of relations, which are often difficult to represent together in information visualizations. Node-link diagrams typically focus on explicit data connections, while not incorporating implicit similarities between entities. Multi-dimensional scaling considers similarities between items, however, explicit links between nodes are not displayed. In contrast, EdgeMaps visualize both implicit and explicit relations by combining and complementing spatialization and graph drawing techniques. As a case study for this approach we chose a dataset of philosophers, their interests, influences, and birthdates. By introducing the limitation of activating only one node at a time, interesting visual patterns emerge that resemble the aesthetics of fireworks and waves. We argue that the interactive exploration of these patterns may allow the viewer to grasp the structure of a graph better than complex node-link visualizations.

Explicit and Implicit Stigma of Mental Illness as Predictors of the Recovery Attitudes of Assertive Community Treatment Practitioners.

PubMed

Stull, Laura G; McConnell, Haley; McGrew, John; Salyers, Michelle P

2017-01-01

While explicit negative stereotypes of mental illness are well established as barriers to recovery, implicit attitudes also may negatively impact outcomes. The current study is unique in its focus on both explicit and implicit stigma as predictors of recovery attitudes of mental health practitioners. Assertive Community Treatment practitioners (n = 154) from 55 teams completed online measures of stigma, recovery attitudes, and an Implicit Association Test (IAT). Three of four explicit stigma variables (perceptions of blameworthiness, helplessness, and dangerousness) and all three implicit stigma variables were associated with lower recovery attitudes. In a multivariate, hierarchical model, however, implicit stigma did not explain additional variance in recovery attitudes. In the overall model, perceptions of dangerousness and implicitly associating mental illness with "bad" were significant individual predictors of lower recovery attitudes. The current study demonstrates a need for interventions to lower explicit stigma, particularly perceptions of dangerousness, to increase mental health providers' expectations for recovery. The extent to which implicit and explicit stigma differentially predict outcomes, including recovery attitudes, needs further research.

Explicit formulation of an anisotropic Allman/DKT 3-node thin triangular flat shell elements

NASA Astrophysics Data System (ADS)

Ertas, A.; Krafcik, J. T.; Ekwaro-Osire, S.

A simple, explicit formulation of the stiffness matrix for an anisotropic, 3-node, thin triangular, flat shell element in global coordinates is presented. An Allman triangle is used for membrane stiffness. The membrane stiffness matrix is explicitly derived by applying an Allman transformation to a Felippa 6-node linear strain triangle (LST). Bending stiffness is incorporated by the use of a discrete Kirchhoff triangle (DKT) bending triangle. Stiffness terms resulting from anisotropic membrane-bending coupling are included by integrating, in area coordinates, membrane and bending strain-displacement matrices.

Toward an Optimal Pedagogy for Teamwork.

PubMed

Earnest, Mark A; Williams, Jason; Aagaard, Eva M

2017-10-01

Teamwork and collaboration are increasingly listed as core competencies for undergraduate health professions education. Despite the clear mandate for teamwork training, the optimal method for providing that training is much less certain. In this Perspective, the authors propose a three-level classification of pedagogical approaches to teamwork training based on the presence of two key learning factors: interdependent work and explicit training in teamwork. In this classification framework, level 1-minimal team learning-is where learners work in small groups but neither of the key learning factors is present. Level 2-implicit team learning-engages learners in interdependent learning activities but does not include an explicit focus on teamwork. Level 3-explicit team learning-creates environments where teams work interdependently toward common goals and are given explicit instruction and practice in teamwork. The authors provide examples that demonstrate each level. They then propose that the third level of team learning, explicit team learning, represents a best practice approach in teaching teamwork, highlighting their experience with an explicit team learning course at the University of Colorado Anschutz Medical Campus. Finally, they discuss several challenges to implementing explicit team-learning-based curricula: the lack of a common teamwork model on which to anchor such a curriculum; the question of whether the knowledge, skills, and attitudes acquired during training would be transferable to the authentic clinical environment; and effectively evaluating the impact of explicit team learning.

Connecting Free Energy Surfaces in Implicit and Explicit Solvent: an Efficient Method to Compute Conformational and Solvation Free Energies

PubMed Central

Deng, Nanjie; Zhang, Bin W.; Levy, Ronald M.

2015-01-01

The ability to accurately model solvent effects on free energy surfaces is important for understanding many biophysical processes including protein folding and misfolding, allosteric transitions and protein-ligand binding. Although all-atom simulations in explicit solvent can provide an accurate model for biomolecules in solution, explicit solvent simulations are hampered by the slow equilibration on rugged landscapes containing multiple basins separated by barriers. In many cases, implicit solvent models can be used to significantly speed up the conformational sampling; however, implicit solvent simulations do not fully capture the effects of a molecular solvent, and this can lead to loss of accuracy in the estimated free energies. Here we introduce a new approach to compute free energy changes in which the molecular details of explicit solvent simulations are retained while also taking advantage of the speed of the implicit solvent simulations. In this approach, the slow equilibration in explicit solvent, due to the long waiting times before barrier crossing, is avoided by using a thermodynamic cycle which connects the free energy basins in implicit solvent and explicit solvent using a localized decoupling scheme. We test this method by computing conformational free energy differences and solvation free energies of the model system alanine dipeptide in water. The free energy changes between basins in explicit solvent calculated using fully explicit solvent paths agree with the corresponding free energy differences obtained using the implicit/explicit thermodynamic cycle to within 0.3 kcal/mol out of ~3 kcal/mol at only ~8 % of the computational cost. We note that WHAM methods can be used to further improve the efficiency and accuracy of the explicit/implicit thermodynamic cycle. PMID:26236174

Connecting free energy surfaces in implicit and explicit solvent: an efficient method to compute conformational and solvation free energies.

PubMed

Deng, Nanjie; Zhang, Bin W; Levy, Ronald M

2015-06-09

The ability to accurately model solvent effects on free energy surfaces is important for understanding many biophysical processes including protein folding and misfolding, allosteric transitions, and protein–ligand binding. Although all-atom simulations in explicit solvent can provide an accurate model for biomolecules in solution, explicit solvent simulations are hampered by the slow equilibration on rugged landscapes containing multiple basins separated by barriers. In many cases, implicit solvent models can be used to significantly speed up the conformational sampling; however, implicit solvent simulations do not fully capture the effects of a molecular solvent, and this can lead to loss of accuracy in the estimated free energies. Here we introduce a new approach to compute free energy changes in which the molecular details of explicit solvent simulations are retained while also taking advantage of the speed of the implicit solvent simulations. In this approach, the slow equilibration in explicit solvent, due to the long waiting times before barrier crossing, is avoided by using a thermodynamic cycle which connects the free energy basins in implicit solvent and explicit solvent using a localized decoupling scheme. We test this method by computing conformational free energy differences and solvation free energies of the model system alanine dipeptide in water. The free energy changes between basins in explicit solvent calculated using fully explicit solvent paths agree with the corresponding free energy differences obtained using the implicit/explicit thermodynamic cycle to within 0.3 kcal/mol out of ∼3 kcal/mol at only ∼8% of the computational cost. We note that WHAM methods can be used to further improve the efficiency and accuracy of the implicit/explicit thermodynamic cycle.

Face puzzle—two new video-based tasks for measuring explicit and implicit aspects of facial emotion recognition

PubMed Central

Kliemann, Dorit; Rosenblau, Gabriela; Bölte, Sven; Heekeren, Hauke R.; Dziobek, Isabel

2013-01-01

Recognizing others' emotional states is crucial for effective social interaction. While most facial emotion recognition tasks use explicit prompts that trigger consciously controlled processing, emotional faces are almost exclusively processed implicitly in real life. Recent attempts in social cognition suggest a dual process perspective, whereby explicit and implicit processes largely operate independently. However, due to differences in methodology the direct comparison of implicit and explicit social cognition has remained a challenge. Here, we introduce a new tool to comparably measure implicit and explicit processing aspects comprising basic and complex emotions in facial expressions. We developed two video-based tasks with similar answer formats to assess performance in respective facial emotion recognition processes: Face Puzzle, implicit and explicit. To assess the tasks' sensitivity to atypical social cognition and to infer interrelationship patterns between explicit and implicit processes in typical and atypical development, we included healthy adults (NT, n = 24) and adults with autism spectrum disorder (ASD, n = 24). Item analyses yielded good reliability of the new tasks. Group-specific results indicated sensitivity to subtle social impairments in high-functioning ASD. Correlation analyses with established implicit and explicit socio-cognitive measures were further in favor of the tasks' external validity. Between group comparisons provide first hints of differential relations between implicit and explicit aspects of facial emotion recognition processes in healthy compared to ASD participants. In addition, an increased magnitude of between group differences in the implicit task was found for a speed-accuracy composite measure. The new Face Puzzle tool thus provides two new tasks to separately assess explicit and implicit social functioning, for instance, to measure subtle impairments as well as potential improvements due to social cognitive interventions. PMID:23805122

Using PPI network autocorrelation in hierarchical multi-label classification trees for gene function prediction.

PubMed

Stojanova, Daniela; Ceci, Michelangelo; Malerba, Donato; Dzeroski, Saso

2013-09-26

Ontologies and catalogs of gene functions, such as the Gene Ontology (GO) and MIPS-FUN, assume that functional classes are organized hierarchically, that is, general functions include more specific ones. This has recently motivated the development of several machine learning algorithms for gene function prediction that leverages on this hierarchical organization where instances may belong to multiple classes. In addition, it is possible to exploit relationships among examples, since it is plausible that related genes tend to share functional annotations. Although these relationships have been identified and extensively studied in the area of protein-protein interaction (PPI) networks, they have not received much attention in hierarchical and multi-class gene function prediction. Relations between genes introduce autocorrelation in functional annotations and violate the assumption that instances are independently and identically distributed (i.i.d.), which underlines most machine learning algorithms. Although the explicit consideration of these relations brings additional complexity to the learning process, we expect substantial benefits in predictive accuracy of learned classifiers. This article demonstrates the benefits (in terms of predictive accuracy) of considering autocorrelation in multi-class gene function prediction. We develop a tree-based algorithm for considering network autocorrelation in the setting of Hierarchical Multi-label Classification (HMC). We empirically evaluate the proposed algorithm, called NHMC (Network Hierarchical Multi-label Classification), on 12 yeast datasets using each of the MIPS-FUN and GO annotation schemes and exploiting 2 different PPI networks. The results clearly show that taking autocorrelation into account improves the predictive performance of the learned models for predicting gene function. Our newly developed method for HMC takes into account network information in the learning phase: When used for gene function prediction in the context of PPI networks, the explicit consideration of network autocorrelation increases the predictive performance of the learned models. Overall, we found that this holds for different gene features/ descriptions, functional annotation schemes, and PPI networks: Best results are achieved when the PPI network is dense and contains a large proportion of function-relevant interactions.

Differentiating for Struggling Readers and Writers: Improving Motivation and Metacognition through Multisensory Methods & Explicit Strategy Instruction

ERIC Educational Resources Information Center

Walet, Jennifer

2011-01-01

This paper examines the issue of struggling readers and writers, and offers suggestions to help teachers increase struggling students' motivation and metacognition. Suggestions include multisensory methods that make use of the visual, auditory and kinesthetic learning pathways, as well as explicit strategy instruction to improve students' ability…

ICCS 2009 User Guide for the International Database. Supplement 4: ICCS 2009 Sampling Stratification Information

ERIC Educational Resources Information Center

Brese, Falk; Jung, Michael; Mirazchiyski, Plamen; Schulz, Wolfram; Zuehlke, Olaf

2011-01-01

This supplement contains documentation on the explicit and implicit stratification variables included in the International Civic and Citizenship Education Study (ICCS) 2009 data files. The explicit strata are smaller sampling frames, created from the national sampling frames, from which national samples of schools were drawn. The implicit strata…

Evaluating spatially explicit burn probabilities for strategic fire management planning

Treesearch

C. Miller; M.-A. Parisien; A. A. Ager; M. A. Finney

2008-01-01

Spatially explicit information on the probability of burning is necessary for virtually all strategic fire and fuels management planning activities, including conducting wildland fire risk assessments, optimizing fuel treatments, and prevention planning. Predictive models providing a reliable estimate of the annual likelihood of fire at each point on the landscape have...

Explicitly Teaching Social Skills Schoolwide: Using a Matrix to Guide Instruction

ERIC Educational Resources Information Center

Simonsen, Brandi; Myers, Diane; Everett, Susannah; Sugai, George; Spencer, Rebecca; LaBreck, Chris

2012-01-01

Socially skilled students are more successful in school. Just like academic skills, social skills need to be explicitly taught. Students, including students who display at-risk behavior, benefit when social skills instruction is delivered schoolwide as part of a comprehensive intervention approach. This article presents a seven-step action…

Advances in the treatment of explicit water molecules in docking and binding free energy calculations.

PubMed

Hu, Xiao; Maffucci, Irene; Contini, Alessandro

2018-05-13

The inclusion of direct effects mediated by water during the ligand-receptor recognition is a hot-topic of modern computational chemistry applied to drug discovery and development. Docking or virtual screening with explicit hydration is still debatable, despite the successful cases that have been presented in the last years. Indeed, how to select the water molecules that will be included in the docking process or how the included waters should be treated remain open questions. In this review, we will discuss some of the most recent methods that can be used in computational drug discovery and drug development when the effect of a single water, or of a small network of interacting waters, needs to be explicitly considered. Here, we analyse software to aid the selection, or to predict the position, of water molecules that are going to be explicitly considered in later docking studies. We also present software and protocols able to efficiently treat flexible water molecules during docking, including examples of applications. Finally, we discuss methods based on molecular dynamics simulations that can be used to integrate docking studies or to reliably and efficiently compute binding energies of ligands in presence of interfacial or bridging water molecules. Software applications aiding the design of new drugs that exploit water molecules, either as displaceable residues or as bridges to the receptor, are constantly being developed. Although further validation is needed, workflows that explicitly consider water will probably become a standard for computational drug discovery soon. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Refining prognosis in lung cancer: A report on the quality and relevance of clinical prognostic tools

PubMed Central

Mahar, Alyson L.; Compton, Carolyn; McShane, Lisa M.; Halabi, Susan; Asamura, Hisao; Rami-Porta, Ramon; Groome, Patti A.

2015-01-01

Introduction Accurate, individualized prognostication for lung cancer patients requires the integration of standard patient and pathologic factors, biologic, genetic, and other molecular characteristics of the tumor. Clinical prognostic tools aim to aggregate information on an individual patient to predict disease outcomes such as overall survival, but little is known about their clinical utility and accuracy in lung cancer. Methods A systematic search of the scientific literature for clinical prognostic tools in lung cancer published Jan 1, 1996-Jan 27, 2015 was performed. In addition, web-based resources were searched. A priori criteria determined by the Molecular Modellers Working Group of the American Joint Committee on Cancer were used to investigate the quality and usefulness of tools. Criteria included clinical presentation, model development approaches, validation strategies, and performance metrics. Results Thirty-two prognostic tools were identified. Patients with metastases were the most frequently considered population in non-small cell lung cancer. All tools for small cell lung cancer covered that entire patient population. Included prognostic factors varied considerably across tools. Internal validity was not formally evaluated for most tools and only eleven were evaluated for external validity. Two key considerations were highlighted for tool development: identification of an explicit purpose related to a relevant clinical population and clear decision-points, and prioritized inclusion of established prognostic factors over emerging factors. Conclusions Prognostic tools will contribute more meaningfully to the practice of personalized medicine if better study design and analysis approaches are used in their development and validation. PMID:26313682

Matching is not naming: a direct comparison of lexical manipulations in explicit and implicit reading tasks.

PubMed

Vogel, Alecia C; Petersen, Steven E; Schlaggar, Bradley L

2013-10-01

The neurobiological basis of reading is of considerable interest, yet analyzing data from subjects reading words aloud during functional MRI data collection can be difficult. Therefore, many investigators use surrogate tasks such as visual matching or rhyme matching to eliminate the need for spoken output. Use of these tasks has been justified by the presumption of "automatic activation" of reading-related neural processing when a word is viewed. We have tested the efficacy of using a nonreading task for studying "reading effects" by directly comparing blood oxygen level dependent (BOLD) activity in subjects performing a visual matching task and an item naming task on words, pseudowords (meaningless but legal letter combinations), and nonwords (meaningless and illegal letter combinations). When compared directly, there is significantly more activity during the naming task in "reading-related" regions such as the inferior frontal gyrus (IFG) and supramarginal gyrus. More importantly, there are differing effects of lexicality in the tasks. A whole-brain task (matching vs. naming) by string type (word vs. pseudoword vs. nonword) by BOLD timecourse analysis identifies regions showing this three-way interaction, including the left IFG and left angular gyrus (AG). In the majority of the identified regions (including the left IFG and left AG), there is a string type × timecourse interaction in the naming but not the matching task. These results argue that the processing performed in specific regions is contingent on task, even in reading-related regions and is thus nonautomatic. Such differences should be taken into consideration when designing studies intended to investigate reading. Copyright © 2012 Wiley Periodicals, Inc.

Predicate calculus, artificial intelligence, and workers' compensation.

PubMed

Harber, P; McCoy, J M

1989-05-01

Application of principles of predicate calculus (PC) and artificial intelligence (AI) search methods to occupational medicine can meet several goals. First, they can improve understanding of the diagnostic process and recognition of the sources of uncertainty in knowledge and in case specific information. Second, PC provides a rational means of resolving differences in conclusion based upon the same premises. Third, understanding of these principles allows separation of knowledge (facts) from the process by which they are used and therefore facilitates development of AI-based expert systems. Application of PC to recognizing causation of pulmonary fibrosis is demonstrated in this paper, providing a method that can be generalized to other problems in occupational medicine. Application of PC and understanding of AI search routines may be particularly applicable to workers' compensation where explicit statement of rational and inferential process is necessary. This approach is useful in the diagnosis of occupational lung disease and may be particularly valuable in workers' compensation considerations, wherein explicit statement of rationale is needed.

Motivated independence? Implicit party identity predicts political judgments among self-proclaimed Independents.

PubMed

Hawkins, Carlee Beth; Nosek, Brian A

2012-11-01

Reporting an Independent political identity does not guarantee the absence of partisanship. Independents demonstrated considerable variability in relative identification with Republicans versus Democrats as measured by an Implicit Association Test (IAT; M = 0.10, SD = 0.47). To test whether this variation predicted political judgment, participants read a newspaper article describing two competing welfare (Study 1) or special education (Study 2) policies. The authors manipulated which policy was proposed by which party. Among self-proclaimed Independents, those who were implicitly Democratic preferred the liberal welfare plan, and those who were implicitly Republican preferred the conservative welfare plan. Regardless of the policy details, these implicit partisans preferred the policy proposed by "their" party, and this effect occurred more strongly for implicit than explicit plan preference. The authors suggest that implicitly partisan Independents may consciously override some partisan influence when making explicit political judgments, and Independents may identify as such to appear objective even when they are not.

Structural kinetic modeling of metabolic networks.

PubMed

Steuer, Ralf; Gross, Thilo; Selbig, Joachim; Blasius, Bernd

2006-08-08

To develop and investigate detailed mathematical models of metabolic processes is one of the primary challenges in systems biology. However, despite considerable advance in the topological analysis of metabolic networks, kinetic modeling is still often severely hampered by inadequate knowledge of the enzyme-kinetic rate laws and their associated parameter values. Here we propose a method that aims to give a quantitative account of the dynamical capabilities of a metabolic system, without requiring any explicit information about the functional form of the rate equations. Our approach is based on constructing a local linear model at each point in parameter space, such that each element of the model is either directly experimentally accessible or amenable to a straightforward biochemical interpretation. This ensemble of local linear models, encompassing all possible explicit kinetic models, then allows for a statistical exploration of the comprehensive parameter space. The method is exemplified on two paradigmatic metabolic systems: the glycolytic pathway of yeast and a realistic-scale representation of the photosynthetic Calvin cycle.

Oceanic signals in rapid polar motion: results from a barotropic forward model with explicit consideration of self-attraction and loading effects

NASA Astrophysics Data System (ADS)

Schindelegger, Michael; Quinn, Katherine J.; Ponte, Rui M.

2017-04-01

Numerical modeling of non-tidal variations in ocean currents and bottom pressure has played a key role in closing the excitation budget of Earth's polar motion for a wide range of periodicities. Non-negligible discrepancies between observations and model accounts of pole position changes prevail, however, on sub-monthly time scales and call for examination of hydrodynamic effects usually omitted in general circulation models. Specifically, complete hydrodynamic cores must incorporate self-attraction and loading (SAL) feedbacks on redistributed water masses, effects that produces ocean bottom pressure perturbations of typically about 10% relative to the computed mass variations. Here, we report on a benchmark simulation with a near-global, barotropic forward model forced by wind stress, atmospheric pressure, and a properly calculated SAL term. The latter is obtained by decomposing ocean mass anomalies on a 30-minute grid into spherical harmonics at each time step and applying Love numbers to account for seafloor deformation and changed gravitational attraction. The increase in computational time at each time step is on the order of 50%. Preliminary results indicate that the explicit consideration of SAL in the forward runs increases the fidelity of modeled polar motion excitations, in particular on time scales shorter than 5 days as evident from cross spectral comparisons with geodetic excitation. Definite conclusions regarding the relevance of SAL in simulating rapid polar motion are, however, still hampered by the model's incomplete domain representation that excludes parts of the highly energetic Arctic Ocean.

A systematic review of clinical audit in companion animal veterinary medicine.

PubMed

Rose, Nicole; Toews, Lorraine; Pang, Daniel S J

2016-02-26

Clinical audit is a quality improvement process with the goal of continuously improving quality of patient care as assessed by explicit criteria. In human medicine clinical audit has become an integral and required component of the standard of care. In contrast, in veterinary medicine there appear to have been a limited number of clinical audits published, indicating that while clinical audit is recognised, its adoption in veterinary medicine is still in its infancy. A systematic review was designed to report and evaluate the veterinary literature on clinical audit in companion animal species (dog, cat, horse). A systematic search of English and French articles using Proquest Dissertations and Theses database (February 6, 2014), CAB Abstracts (March 21, 2014 and April 4, 2014), Scopus (March 21, 2014), Web of Science Citation index (March 21, 2014) and OVID Medline (March 21, 2014) was performed. Included articles were those either discussing clinical audit (such as review articles and editorials) or reporting parts of, or complete, audit cycles. The majority of articles describing clinical audit were reviews. From 89 articles identified, twenty-one articles were included and available for review. Twelve articles were reviews of clinical audit in veterinary medicine, five articles included at least one veterinary clinical audit, one thesis was identified, one report was of a veterinary clinical audit website and two articles reported incomplete clinical audits. There was no indication of an increase in the number of published clinical audits since the first report in 1998. However, there was evidence of article misclassification, with studies fulfilling the criteria of clinical audit not appropriately recognised. Quality of study design and reporting of findings varied considerably, with information missing on key components, including duration of study, changes in practice implemented between audits, development of explicit criteria and appropriate statistical analyses. Available evidence suggests the application and reporting of clinical audit in veterinary medicine is sporadic despite the potential to improve patient care, though the true incidence of clinical audit reporting is likely to be underestimated due to incorrect indexing. Reporting standards of clinical audits are highly variable, limiting evaluation, application and repeatability of published work.

Cost considerations for long-term ecological monitoring

USGS Publications Warehouse

Caughlan, L.; Oakley, K.L.

2001-01-01

For an ecological monitoring program to be successful over the long-term, the perceived benefits of the information must justify the cost. Financial limitations will always restrict the scope of a monitoring program, hence the program's focus must be carefully prioritized. Clearly identifying the costs and benefits of a program will assist in this prioritization process, but this is easier said than done. Frequently, the true costs of monitoring are not recognized and are, therefore, underestimated. Benefits are rarely evaluated, because they are difficult to quantify. The intent of this review is to assist the designers and managers of long-term ecological monitoring programs by providing a general framework for building and operating a cost-effective program. Previous considerations of monitoring costs have focused on sampling design optimization. We present cost considerations of monitoring in a broader context. We explore monitoring costs, including both budgetary costs--what dollars are spent on--and economic costs, which include opportunity costs. Often, the largest portion of a monitoring program budget is spent on data collection, and other, critical aspects of the program, such as scientific oversight, training, data management, quality assurance, and reporting, are neglected. Recognizing and budgeting for all program costs is therefore a key factor in a program's longevity. The close relationship between statistical issues and cost is discussed, highlighting the importance of sampling design, replication and power, and comparing the costs of alternative designs through pilot studies and simulation modeling. A monitoring program development process that includes explicit checkpoints for considering costs is presented. The first checkpoint occur during the setting of objectives and during sampling design optimization. The last checkpoint occurs once the basic shape of the program is known, and the costs and benefits, or alternatively the cost-effectiveness, of each program element can be evaluated. Moving into the implementation phase without careful evaluation of costs and benefits is risky because if costs are later found to exceed benefits, the program will fail. The costs of development, which can be quite high, will have been largely wasted. Realistic expectations of costs and benefits will help ensure that monitoring programs survive the early, turbulent stages of development and the challenges posed by fluctuating budgets during implementation.

Implicit measures of the stereotype content associated with disability.

PubMed

Rohmer, Odile; Louvet, Eva

2012-12-01

The present research aimed to show that the mixed stereotype content of persons with disability observed at an explicit level does not manifest itself using implicit measures. Two experimental studies were conducted to analyse the stereotype content of persons with a disability at the implicit level. The procedure used in this study was the concept priming paradigm. Furthermore, Study 2 also included an explicit measure. Results show important discrepancies between implicit and explicit measures. At an explicit level, previous work supporting the mixed stereotype content of persons with disability was replicated: participants judged these persons as warmer but less competent than persons without a disability. At an implicit level, a quite different pattern of results emerged: persons with a disability were associated not only with less competence than persons without disability, but also with less warmth. These findings suggest that the mixed pattern between warmth and competence generally observed at an explicit level may be based on societal pressures against prejudice and discrimination. ©2012 The British Psychological Society.

Valuing Healthcare Improvement: Implicit Norms, Explicit Normativity, and Human Agency.

PubMed

Carter, Stacy M

2018-06-01

I argue that greater attention to human agency and normativity in both researching and practicing service improvement may be one strategy for enhancing improvement science, illustrating with examples from cancer screening. Improvement science tends to deliberately avoid explicit normativity, for paradigmatically coherent reasons. But there are good reasons to consider including explicit normativity in thinking about improvement. Values and moral judgements are central to social life, so an adequate account of social life must include these elements. And improvement itself is unavoidably normative: it assumes that things could and should be better than they are. I seek to show that normativity will always be implicated in the creation of evidence, the design of programs, the practice of healthcare, and in citizens' judgements about that care, and to make a case that engaging with this normativity is worthwhile.

The Environment Makes a Difference: The Impact of Explicit and Implicit Attitudes as Precursors in Different Food Choice Tasks

PubMed Central

König, Laura M.; Giese, Helge; Schupp, Harald T.; Renner, Britta

2016-01-01

Studies show that implicit and explicit attitudes influence food choice. However, precursors of food choice often are investigated using tasks offering a very limited number of options despite the comparably complex environment surrounding real life food choice. In the present study, we investigated how the assortment impacts the relationship between implicit and explicit attitudes and food choice (confectionery and fruit), assuming that a more complex choice architecture is more taxing on cognitive resources. Specifically, a binary and a multiple option choice task based on the same stimulus set (fake food items) were presented to ninety-seven participants. Path modeling revealed that both explicit and implicit attitudes were associated with relative food choice (confectionery vs. fruit) in both tasks. In the binary option choice task, both explicit and implicit attitudes were significant precursors of food choice, with explicit attitudes having a greater impact. Conversely, in the multiple option choice task, the additive impact of explicit and implicit attitudes was qualified by an interaction indicating that, even if explicit and implicit attitudes toward confectionery were inconsistent, more confectionery was chosen than fruit if either was positive. This compensatory ‘one is sufficient’-effect indicates that the structure of the choice environment modulates the relationship between attitudes and choice. The study highlights that environmental constraints, such as the number of choice options, are an important boundary condition that need to be included when investigating the relationship between psychological precursors and behavior. PMID:27621719

The Environment Makes a Difference: The Impact of Explicit and Implicit Attitudes as Precursors in Different Food Choice Tasks.

PubMed

König, Laura M; Giese, Helge; Schupp, Harald T; Renner, Britta

2016-01-01

Studies show that implicit and explicit attitudes influence food choice. However, precursors of food choice often are investigated using tasks offering a very limited number of options despite the comparably complex environment surrounding real life food choice. In the present study, we investigated how the assortment impacts the relationship between implicit and explicit attitudes and food choice (confectionery and fruit), assuming that a more complex choice architecture is more taxing on cognitive resources. Specifically, a binary and a multiple option choice task based on the same stimulus set (fake food items) were presented to ninety-seven participants. Path modeling revealed that both explicit and implicit attitudes were associated with relative food choice (confectionery vs. fruit) in both tasks. In the binary option choice task, both explicit and implicit attitudes were significant precursors of food choice, with explicit attitudes having a greater impact. Conversely, in the multiple option choice task, the additive impact of explicit and implicit attitudes was qualified by an interaction indicating that, even if explicit and implicit attitudes toward confectionery were inconsistent, more confectionery was chosen than fruit if either was positive. This compensatory 'one is sufficient'-effect indicates that the structure of the choice environment modulates the relationship between attitudes and choice. The study highlights that environmental constraints, such as the number of choice options, are an important boundary condition that need to be included when investigating the relationship between psychological precursors and behavior.

Two-spoke placement optimization under explicit specific absorption rate and power constraints in parallel transmission at ultra-high field.

PubMed

Dupas, Laura; Massire, Aurélien; Amadon, Alexis; Vignaud, Alexandre; Boulant, Nicolas

2015-06-01

The spokes method combined with parallel transmission is a promising technique to mitigate the B1(+) inhomogeneity at ultra-high field in 2D imaging. To date however, the spokes placement optimization combined with the magnitude least squares pulse design has never been done in direct conjunction with the explicit Specific Absorption Rate (SAR) and hardware constraints. In this work, the joint optimization of 2-spoke trajectories and RF subpulse weights is performed under these constraints explicitly and in the small tip angle regime. The problem is first considerably simplified by making the observation that only the vector between the 2 spokes is relevant in the magnitude least squares cost-function, thereby reducing the size of the parameter space and allowing a more exhaustive search. The algorithm starts from a set of initial k-space candidates and performs in parallel for all of them optimizations of the RF subpulse weights and the k-space locations simultaneously, under explicit SAR and power constraints, using an active-set algorithm. The dimensionality of the spoke placement parameter space being low, the RF pulse performance is computed for every location in k-space to study the robustness of the proposed approach with respect to initialization, by looking at the probability to converge towards a possible global minimum. Moreover, the optimization of the spoke placement is repeated with an increased pulse bandwidth in order to investigate the impact of the constraints on the result. Bloch simulations and in vivo T2(∗)-weighted images acquired at 7 T validate the approach. The algorithm returns simulated normalized root mean square errors systematically smaller than 5% in 10 s. Copyright © 2015 Elsevier Inc. All rights reserved.

When the body reveals the mind: Children's use of others' body orientation to understand their focus of attention.

PubMed

Paulus, Markus; Murillo, Esther; Sodian, Beate

2016-08-01

A considerable amount of research has examined children's ability to rely on explicit social cues such as pointing to understand others' referential intentions. Yet, skillful social interaction also requires reliance on and learning from implicit cues (i.e., cues that are not displayed with the explicit intention to teach or inform someone). From an embodied point of view, orienting movements and body orientation are salient cues that reveal something about a person's intentional relations without being explicit communicative cues. In three experiments, the current study investigated the development of the ability to use body information in a word learning situation. To this end, we presented 2-year-old children, 3.5-year-old children, and adults with movies on an eye-tracking screen in which an actor oriented her upper body to one of two objects while uttering a novel word. The results show that the 3.5-year-old children and adults, but not the 2-year-old children, related the novel word to the referred object (Experiments 1 and 2). Yet, when the actor oriented her body to one object while pointing to the other object, children of both age groups relied on the pointing cue (Experiment 3). This suggests that by 3.5 years children use another's body orientation as an indicator of her intentional relations but that they prioritize explicit social cues over the implicit body posture cues. Overall, the study supports theoretical views that an appreciation of others' intentional relations does not emerge as an all-or-nothing ability but rather emerges gradually during the course of early development. Copyright © 2016 Elsevier Inc. All rights reserved.

Commentary: Writing and Evaluating Qualitative Research Reports.

PubMed

Wu, Yelena P; Thompson, Deborah; Aroian, Karen J; McQuaid, Elizabeth L; Deatrick, Janet A

2016-06-01

To provide an overview of qualitative methods, particularly for reviewers and authors who may be less familiar with qualitative research. A question and answer format is used to address considerations for writing and evaluating qualitative research. When producing qualitative research, individuals are encouraged to address the qualitative research considerations raised and to explicitly identify the systematic strategies used to ensure rigor in study design and methods, analysis, and presentation of findings. Increasing capacity for review and publication of qualitative research within pediatric psychology will advance the field's ability to gain a better understanding of the specific needs of pediatric populations, tailor interventions more effectively, and promote optimal health. © The Author 2016. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Dual-loop model of the human controller

NASA Technical Reports Server (NTRS)

Hess, R. A.

1978-01-01

A dual-loop model of the human controller in single-axis compensatory tracking tasks is introduced. This model possesses an inner-loop closure that involves feeding back that portion of controlled element output rate that is due to control activity. A novel feature of the model is the explicit appearance of the human's internal representation of the manipulator-controlled element dynamics in the inner loop. The sensor inputs to the human controller are assumed to be system error and control force. The former can be sensed via visual, aural, or tactile displays, whereas the latter is assumed to be sensed in kinesthetic fashion. A set of general adaptive characteristics for the model is hypothesized, including a method for selecting simplified internal models of the manipulator-controlled element dynamics. It is demonstrated that the model can produce controller describing functions that closely approximate those measured in four laboratory tracking tasks in which the controlled element dynamics vary considerably in terms of ease of control. An empirically derived expression for the normalized injected error remnant spectrum is introduced.

Layer-switching cost and optimality in information spreading on multiplex networks

PubMed Central

Min, Byungjoon; Gwak, Sang-Hwan; Lee, Nanoom; Goh, K. -I.

2016-01-01

We study a model of information spreading on multiplex networks, in which agents interact through multiple interaction channels (layers), say online vs. offline communication layers, subject to layer-switching cost for transmissions across different interaction layers. The model is characterized by the layer-wise path-dependent transmissibility over a contact, that is dynamically determined dependently on both incoming and outgoing transmission layers. We formulate an analytical framework to deal with such path-dependent transmissibility and demonstrate the nontrivial interplay between the multiplexity and spreading dynamics, including optimality. It is shown that the epidemic threshold and prevalence respond to the layer-switching cost non-monotonically and that the optimal conditions can change in abrupt non-analytic ways, depending also on the densities of network layers and the type of seed infections. Our results elucidate the essential role of multiplexity that its explicit consideration should be crucial for realistic modeling and prediction of spreading phenomena on multiplex social networks in an era of ever-diversifying social interaction layers. PMID:26887527

Higher spin gravitational couplings: Ghosts in the Yang-Mills detour complex

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

Gover, A. R.; Hallowell, K.; Waldron, A.

2007-01-15

Gravitational interactions of higher spin fields are generically plagued by inconsistencies. There exists however, a simple framework that couples higher spins to a broad class of gravitational backgrounds (including Ricci flat and Einstein) consistently at the classical level. The model is the simplest example of a Yang-Mills detour complex and has broad mathematical applications, especially to conformal geometry. Even the simplest version of the theory, which couples gravitons, vectors and scalar fields in a flat background is rather rich, providing an explicit setting for detailed analysis of ghost excitations. Its asymptotic scattering states consist of a physical massless graviton, scalar,more » and massive vector along with a degenerate pair of zero norm photon excitations. Coherent states of the unstable sector do have positive norms, but their evolution is no longer unitary and amplitudes grow with time. The class of models proposed is extremely general and of considerable interest for ghost condensation and invariant theory.« less

Sibling self-management: Programming for generalization to improve interactions between typically developing siblings and children with autism spectrum disorders.

PubMed

Kryzak, Lauren A; Jones, Emily A

2017-11-01

The present study taught typically developing (TD) siblings of children with autism spectrum disorders (ASD) social-communicative and self-management skills. The authors' hypothesized that the acquisition of self-management skills would support generalization of targeted social-communicative responses. A multiple baseline probe design across sibling dyads was used to decrease exposure to unnecessary sessions in the absence of intervention. Four TD siblings were taught self-management of a social skills curriculum using behavioral skills training, which consisted of instructions, modeling, practice, and subsequent feedback. Results indicated that TD siblings learned to self-manage the social skills curriculum with some generalization across novel settings and over time. Comparisons of social-communicative responses to their typical peers provided some support for the social validity of the intervention outcomes. These results support the use of self-management, when explicitly programming for generalization, which continues to be a key consideration when including TD siblings in interventions with their siblings with ASD.

Addressing the determinants of child mental health: intersectionality as a guide to primary health care renewal.

PubMed

McPherson, Charmaine M; McGibbon, Elizabeth A

2010-09-01

Primary health care (PHC) renewal was designed explicitly to attend to the multidimensional factors impacting on health, including the social determinants of health. These determinants are central considerations in the development of integrated, cross-sectoral, and multi-jurisdictional policies such as those that inform models of shared mental health care for children. However, there are complex theoretical challenges in translating these multidimensional issues into policy. One of these is the rarely discussed interrelationships among the social determinants of health and identities such as race, gender, age, sexuality, and social class within the added confluence of geographic contexts. An intersectionality lens is used to examine the complex interrelationships among the factors affecting child mental health and the associated policy challenges surrounding PHC renewal. The authors argue that an understanding of the intersections of social determinants of health, identity, and geography is pivotal in guiding policy-makers as they address child mental health inequities using a PHC renewal agenda.

Forced nutations of the earth: Influence of inner core dynamics. I - Theory. II - Numerical results and comparisons. III - Very long interferometry data analysis

NASA Technical Reports Server (NTRS)

Mathews, P. M.; Buffett, Bruce A.; Herring, Thomas A.; Shapiro, Irwin I.

1991-01-01

A treatment is presented of the nutation problem for an oceanless, elastic, spheroidally stratified earth, with the dynamical role of the inner core explicitly included in the formulation. Solving the enlarged system of equations shows that a new almost diurnal eigenfrequency emerges. A rough estimate places it not far from the prograde annual tidal excitation frequency, so that possible resonance effects on nutation amplitudes need careful consideration. Tables are provided that exhibit the sensitivities of various relevant quantities, the eigenfrequencies and the coefficients which appear in the resonance expansion, as well as the nutation amplitudes at important tidal frequencies, to possible errors in the earth parameters which enter the theory set forth. Finally, the analysis of 798 VLBI experiments performed between July 1980 and February 1989 and the determination from this analysis of corrections to selected coefficients in the International Astronomical Union 1980 theory of the nutations of the earth are discussed.

Navigating around the algebraic jungle of QCD: efficient evaluation of loop helicity amplitudes

NASA Astrophysics Data System (ADS)

Lam, C. S.

1993-05-01

A method is developed whereby spinor helicity techniques can be used to simlify the calculation of loop amplitudes. This is achieved by using the Feynman-parameter representation where the offending off-shell loop momenta do not appear. Other shortcuts motivated by the Bern-Kosower one-loop string calculations can be incorporated into the formalism. This includes color reorganization into Chan-Paton factors and the use of background Feynman gauge. This method is applicable to any Feynman diagram with any number of loops as long as the external masses can be ignored. In order to minimize the very considerable algebra encountered in non-abelian gauge theories, graphical methods are developed for most of the calculations. This enables the large number of terms encountered to be organized implicitly in the Feynman diagram without the necessity of writing down any of them algebraically. A one-loop four-gluon amplitude in a particular helicity configuration is computed explicitly to illustrate the method.

Emotional engineers: toward morally responsible design.

PubMed

Roeser, Sabine

2012-03-01

Engineers are normally seen as the archetype of people who make decisions in a rational and quantitative way. However, technological design is not value neutral. The way a technology is designed determines its possibilities, which can, for better or for worse, have consequences for human wellbeing. This leads various scholars to the claim that engineers should explicitly take into account ethical considerations. They are at the cradle of new technological developments and can thereby influence the possible risks and benefits more directly than anybody else. I have argued elsewhere that emotions are an indispensable source of ethical insight into ethical aspects of risk. In this paper I will argue that this means that engineers should also include emotional reflection into their work. This requires a new understanding of the competencies of engineers: they should not be unemotional calculators; quite the opposite, they should work to cultivate their moral emotions and sensitivity, in order to be engaged in morally responsible engineering. © The Author(s) 2010. This article is published with open access at Springerlink.com

Annual Irrigation Dynamics in the U.S. Northern High Plains Derived from Landsat Satellite Data

NASA Astrophysics Data System (ADS)

Deines, Jillian M.; Kendall, Anthony D.; Hyndman, David W.

2017-09-01

Sustainable management of agricultural water resources requires improved understanding of irrigation patterns in space and time. We produced annual, high-resolution (30 m) irrigation maps for 1999-2016 by combining all available Landsat satellite imagery with climate and soil covariables in Google Earth Engine. Random forest classification had accuracies from 92 to 100% and generally agreed with county statistics (r2 = 0.88-0.96). Two novel indices that integrate plant greenness and moisture information show promise for improving satellite classification of irrigation. We found considerable interannual variability in irrigation location and extent, including a near doubling between 2002 and 2016. Statistical modeling suggested that precipitation and commodity price influenced irrigated extent through time. High prices incentivized expansion to increase crop yield and profit, but dry years required greater irrigation intensity, thus reducing area in this supply-limited region. Data sets produced with this approach can improve water sustainability by providing consistent, spatially explicit tracking of irrigation dynamics over time.

The cognitive dismantling of Eye Movement Desensitization and Reprocessing (EMDR) treatment of Posttraumatic Stress Disorder (PTSD).

PubMed

Cusack, K; Spates, C R

1999-01-01

Twenty-seven subjects were exposed to standard Eye Movement Desensitization and Reprocessing (EMDR) treatment or a similar treatment without the explicit cognitive elements found in EMDR. Standardized psychometric assessments were administered (Structured Interview for Post Traumatic Stress Disorder, Impact of Event Scale, Revised Symptom Checklist-90) by independent assessors at pretest, posttest and two separate follow-up periods. Potential subjects met specific inclusion/exclusion criteria. Subjective measures including Subjective Units of Disturbance and Validity of Cognition assessments were also conducted. A two-factor repeated measures analysis of variance revealed that both treatments produced significant symptom reductions and were comparable on all dependent measures across assessment phases. The present findings are discussed in light of previous dismantling research that converges to suggest that several elements in the EMDR protocol may be superfluous in terms of the contribution to treatment outcome. These same elements have nevertheless entered unparsimoniously into consideration as possible explanatory variables.

The Effect of Explicit-Reflective and Historical Approach on Preservice Elementary Teachers' Views of Nature of Science

ERIC Educational Resources Information Center

Pekbay, Canay; Yilmaz, Serkan

2015-01-01

This study aims to explore the influence of nature of science (NOS) activities based on explicit-reflective and historical approach on preservice elementary teachers' views of NOS aspects. Mixed-method approach including both qualitative and quantitative methods was used. The sample consisted of 83 preservice elementary teachers of a public…

An Attempt to Raise Japanese EFL Learners' Pragmatic Awareness Using Online Discourse Completion Tasks

ERIC Educational Resources Information Center

Tanaka, Hiroya; Oki, Nanaho

2015-01-01

This practical paper discusses the effect of explicit instruction to raise Japanese EFL learners' pragmatic awareness using online discourse completion tasks. The five-part tasks developed by the authors use American TV drama scenes depicting particular speech acts and include explicit instruction in these speech acts. 46 Japanese EFL college…

Awakening the Scientist Inside: Global Climate Change and the Nature of Science in an Elementary Science Methods Course

ERIC Educational Resources Information Center

Matkins, Juanita Jo; Bell, Randy L.

2007-01-01

This investigation assessed the impact of situating explicit nature of science (NOS) instruction within the issues surrounding global climate change and global warming (GCC/GW). Participants in the study were 15 preservice elementary teachers enrolled in a science methods course. The instructional intervention included explicit NOS instruction…

Transfer-of-Training Effects in Processing Instruction: The Role of Form-Related Explicit Information

ERIC Educational Resources Information Center

White, Justin P.; DeMil, Andrew J.

2013-01-01

This study compares the effects of processing instruction (PI), structured input (SI), and form-related explicit information (FREI) on a primary target form (i.e., third-person Spanish accusative clitics) and on a secondary form (i.e., third-person Spanish dative clitics). Participants included 151 adult learners enrolled in a beginning-level…

Do Children with Social Communication Disorder Have Explicit Knowledge of Pragmatic Rules They Break? A Comparison of Conversational Pragmatic Ability and Metapragmatic Awareness

ERIC Educational Resources Information Center

Lockton, Elaine; Adams, Catherine; Collins, Anna

2016-01-01

Background: Children who have social communication disorder (CwSCD) demonstrate persistent difficulties with language pragmatics in conversations and other verbal interactions. Speech-language interventions for these children often include promotion of metapragmatic awareness (MPA); that is, the ability to identify explicitly and reflect upon…

Modeling Physiological Processes That Relate Toxicant Exposure and Bacterial Population Dynamics

PubMed Central

Klanjscek, Tin; Nisbet, Roger M.; Priester, John H.; Holden, Patricia A.

2012-01-01

Quantifying effects of toxicant exposure on metabolic processes is crucial to predicting microbial growth patterns in different environments. Mechanistic models, such as those based on Dynamic Energy Budget (DEB) theory, can link physiological processes to microbial growth. Here we expand the DEB framework to include explicit consideration of the role of reactive oxygen species (ROS). Extensions considered are: (i) additional terms in the equation for the “hazard rate” that quantifies mortality risk; (ii) a variable representing environmental degradation; (iii) a mechanistic description of toxic effects linked to increase in ROS production and aging acceleration, and to non-competitive inhibition of transport channels; (iv) a new representation of the “lag time” based on energy required for acclimation. We estimate model parameters using calibrated Pseudomonas aeruginosa optical density growth data for seven levels of cadmium exposure. The model reproduces growth patterns for all treatments with a single common parameter set, and bacterial growth for treatments of up to 150 mg(Cd)/L can be predicted reasonably well using parameters estimated from cadmium treatments of 20 mg(Cd)/L and lower. Our approach is an important step towards connecting levels of biological organization in ecotoxicology. The presented model reveals possible connections between processes that are not obvious from purely empirical considerations, enables validation and hypothesis testing by creating testable predictions, and identifies research required to further develop the theory. PMID:22328915

Implicit time accurate simulation of unsteady flow

NASA Astrophysics Data System (ADS)

van Buuren, René; Kuerten, Hans; Geurts, Bernard J.

2001-03-01

Implicit time integration was studied in the context of unsteady shock-boundary layer interaction flow. With an explicit second-order Runge-Kutta scheme, a reference solution to compare with the implicit second-order Crank-Nicolson scheme was determined. The time step in the explicit scheme is restricted by both temporal accuracy as well as stability requirements, whereas in the A-stable implicit scheme, the time step has to obey temporal resolution requirements and numerical convergence conditions. The non-linear discrete equations for each time step are solved iteratively by adding a pseudo-time derivative. The quasi-Newton approach is adopted and the linear systems that arise are approximately solved with a symmetric block Gauss-Seidel solver. As a guiding principle for properly setting numerical time integration parameters that yield an efficient time accurate capturing of the solution, the global error caused by the temporal integration is compared with the error resulting from the spatial discretization. Focus is on the sensitivity of properties of the solution in relation to the time step. Numerical simulations show that the time step needed for acceptable accuracy can be considerably larger than the explicit stability time step; typical ratios range from 20 to 80. At large time steps, convergence problems that are closely related to a highly complex structure of the basins of attraction of the iterative method may occur. Copyright

Why do morphological phylogenies vary in quality? An investigation based on the comparative history of lizard clades.

PubMed

Arnold, E N

1990-05-22

Phylogenies based on morphology vary considerably in their quality: some are robust and explicit with little conflict in the data set, whereas others are far more tenuous, with much conflict and many possible alternatives. The main primary reasons for untrue or inexplicit morphological phylogenies are: not enough characters developed between branching points, uncertain character polarity, poorly differentiated character states, homoplasy caused by parallelism or reversal, and extinction, which may remove species entirely from consideration and can make originally conflicting data sets misleadingly compatible, increasing congruence at the expense of truth. Extinction differs from other confounding factors in not being apparent either in the data set or in subsequent analysis. One possibility is that variation in the quality of morphological phylogenies has resulted from exposure to different ecological situations. To investigate this, it is necessary to compare the histories of the clades concerned. In the case of explicit morphological phylogenies, ecological and behavioural data can be integrated with them and it may then be possible to decide whether morphological characters are likely to have been elicited by the environments through which the clade has passed. The credibility of such results depends not only on the phylogeny being robust but also on its detailed topology: a pectinate phylogeny will often allow more certain and more explicit statements to be made about historical events. In the case of poor phylogenies, it is not possible to produce detailed histories, but they can be compared with robust phylogenies in the range of ecological situations occupied, and whether they occupy novel situations in comparison with their outgroups. LeQuesne testing can give information about niche homoplasy, and it may also be possible to see if morphological features are functionally associated with ecological parameters, even if the direction of change is unknown. Examination of the robust and explicit phylogeny of the semaphore geckoes (Pristurus) suggests that its quality does stem from a variety of environmental factors. The group has progressed along an ecological continuum, passing through a series of increasingly severe niches that appear to have elicited many morphological changes. The fact that niches are progressively filled reduces the likelihood of species reinvading a previous one with related character reversal. Because the niches of advanced Pristurus are virtually unique within the Gekkonidae the morphological changes produced are also very rare and therefore easy to polarize. Ecological changes on the main stem of the phylogeny are abrupt and associated character states consequently well differentiated.(ABSTRACT TRUNCATED AT 400 WORDS)

Spatially-Explicit Simulation Modeling of Ecological Response to Climate Change: Methodological Considerations in Predicting Shifting Population Dynamics of Infectious Disease Vectors.

PubMed

Dhingra, Radhika; Jimenez, Violeta; Chang, Howard H; Gambhir, Manoj; Fu, Joshua S; Liu, Yang; Remais, Justin V

2013-09-01

Poikilothermic disease vectors can respond to altered climates through spatial changes in both population size and phenology. Quantitative descriptors to characterize, analyze and visualize these dynamic responses are lacking, particularly across large spatial domains. In order to demonstrate the value of a spatially explicit, dynamic modeling approach, we assessed spatial changes in the population dynamics of Ixodes scapularis , the Lyme disease vector, using a temperature-forced population model simulated across a grid of 4 × 4 km cells covering the eastern United States, using both modeled (Weather Research and Forecasting (WRF) 3.2.1) baseline/current (2001-2004) and projected (Representative Concentration Pathway (RCP) 4.5 and RCP 8.5; 2057-2059) climate data. Ten dynamic population features (DPFs) were derived from simulated populations and analyzed spatially to characterize the regional population response to current and future climate across the domain. Each DPF under the current climate was assessed for its ability to discriminate observed Lyme disease risk and known vector presence/absence, using data from the US Centers for Disease Control and Prevention. Peak vector population and month of peak vector population were the DPFs that performed best as predictors of current Lyme disease risk. When examined under baseline and projected climate scenarios, the spatial and temporal distributions of DPFs shift and the seasonal cycle of key questing life stages is compressed under some scenarios. Our results demonstrate the utility of spatial characterization, analysis and visualization of dynamic population responses-including altered phenology-of disease vectors to altered climate.

Spatially-Explicit Simulation Modeling of Ecological Response to Climate Change: Methodological Considerations in Predicting Shifting Population Dynamics of Infectious Disease Vectors

PubMed Central

Dhingra, Radhika; Jimenez, Violeta; Chang, Howard H.; Gambhir, Manoj; Fu, Joshua S.; Liu, Yang; Remais, Justin V.

2014-01-01

Poikilothermic disease vectors can respond to altered climates through spatial changes in both population size and phenology. Quantitative descriptors to characterize, analyze and visualize these dynamic responses are lacking, particularly across large spatial domains. In order to demonstrate the value of a spatially explicit, dynamic modeling approach, we assessed spatial changes in the population dynamics of Ixodes scapularis, the Lyme disease vector, using a temperature-forced population model simulated across a grid of 4 × 4 km cells covering the eastern United States, using both modeled (Weather Research and Forecasting (WRF) 3.2.1) baseline/current (2001–2004) and projected (Representative Concentration Pathway (RCP) 4.5 and RCP 8.5; 2057–2059) climate data. Ten dynamic population features (DPFs) were derived from simulated populations and analyzed spatially to characterize the regional population response to current and future climate across the domain. Each DPF under the current climate was assessed for its ability to discriminate observed Lyme disease risk and known vector presence/absence, using data from the US Centers for Disease Control and Prevention. Peak vector population and month of peak vector population were the DPFs that performed best as predictors of current Lyme disease risk. When examined under baseline and projected climate scenarios, the spatial and temporal distributions of DPFs shift and the seasonal cycle of key questing life stages is compressed under some scenarios. Our results demonstrate the utility of spatial characterization, analysis and visualization of dynamic population responses—including altered phenology—of disease vectors to altered climate. PMID:24772388

SPREADING SPEEDS AND TRAVELING WAVES FOR NON-COOPERATIVE INTEGRO-DIFFERENCE SYSTEMS

PubMed Central

Wang, Haiyan; Castillo-Chavez, Carlos

2014-01-01

The study of spatially explicit integro-difference systems when the local population dynamics are given in terms of discrete-time generations models has gained considerable attention over the past two decades. These nonlinear systems arise naturally in the study of the spatial dispersal of organisms. The brunt of the mathematical research on these systems, particularly, when dealing with cooperative systems, has focused on the study of the existence of traveling wave solutions and the characterization of their spreading speed. Here, we characterize the minimum propagation (spreading) speed, via the convergence of initial data to wave solutions, for a large class of non cooperative nonlinear systems of integro-difference equations. The spreading speed turns out to be the slowest speed from a family of non-constant traveling wave solutions. The applicability of these theoretical results is illustrated through the explicit study of an integro-difference system with local population dynamics governed by Hassell and Comins’ non-cooperative competition model (1976). The corresponding integro-difference nonlinear systems that results from the redistribution of individuals via a dispersal kernel is shown to satisfy conditions that guarantee the existence of minimum speeds and traveling waves. This paper is dedicated to Avner Friedman as we celebrate his immense contributions to the fields of partial differential equations, integral equations, mathematical biology, industrial mathematics and applied mathematics in general. His leadership in the mathematical sciences and his mentorship of students and friends over several decades has made a huge difference in the personal and professional lives of many, including both of us. PMID:24899868

A cluster randomised trial of a school-based resilience intervention to decrease tobacco, alcohol and illicit drug use in secondary school students: study protocol.

PubMed

Hodder, Rebecca K; Freund, Megan; Bowman, Jenny; Wolfenden, Luke; Campbell, Elizabeth; Wye, Paula; Hazell, Trevor; Gillham, Karen; Wiggers, John

2012-11-21

Whilst schools provide a potentially appropriate setting for preventing substance use among young people, systematic review evidence suggests that past interventions in this setting have demonstrated limited effectiveness in preventing tobacco, alcohol and other drug use. Interventions that adopt a mental wellbeing approach to prevent substance use offer considerable promise and resilience theory provides one method to impact on adolescent mental well-being. The aim of the proposed study is to examine the efficacy of a resilience intervention in decreasing the tobacco, alcohol and illicit drug use of adolescents. A cluster randomised controlled trial with schools as the unit of randomisation will be undertaken. Thirty two schools in disadvantaged areas will be allocated to either an intervention or a control group. A comprehensive resilience intervention will be implemented, inclusive of explicit program adoption strategies. Baseline surveys will be conducted with students in Grade 7 in both groups and again three years later when the student cohort is in Grade 10. The primary outcome measures will include self-reported tobacco, alcohol, marijuana and other illicit drug use. Comparisons will be made post-test between Grade 10 students in intervention and control schools to determine intervention effectiveness across all measures. To the authors' knowledge this is the first randomised controlled trial to evaluate the effectiveness of a comprehensive school-based resilience intervention, inclusive of explicit adoption strategies, in decreasing tobacco, alcohol and illicit drug use of adolescents attending disadvantaged secondary schools. ACTRN12611000606987.

Prevalence and characteristics of youth sexting: a national study.

PubMed

Mitchell, Kimberly J; Finkelhor, David; Jones, Lisa M; Wolak, Janis

2012-01-01

To obtain national estimates of youth involved in sexting in the past year (the transmission via cell phone, the Internet, and other electronic media of sexual images), as well as provide details of the youth involved and the nature of the sexual images. The study was based on a cross-sectional national telephone survey of 1560 youth Internet users, ages 10 through 17. Estimates varied considerably depending on the nature of the images or videos and the role of the youth involved. Two and one-half percent of youth had appeared in or created nude or nearly nude pictures or videos. However, this percentage is reduced to 1.0% when the definition is restricted to only include images that were sexually explicit (ie, showed naked breasts, genitals, or bottoms). Of the youth who participated in the survey, 7.1% said they had received nude or nearly nude images of others; 5.9% of youth reported receiving sexually explicit images. Few youth distributed these images. Because policy debates on youth sexting behavior focus on concerns about the production and possession of illegal child pornography, it is important to have research that collects details about the nature of the sexual images rather than using ambiguous screening questions without follow-ups. The rate of youth exposure to sexting highlights a need to provide them with information about legal consequences of sexting and advice about what to do if they receive a sexting image. However, the data suggest that appearing in, creating, or receiving sexual images is far from being a normative behavior for youth.

A cluster randomised trial of a school-based resilience intervention to decrease tobacco, alcohol and illicit drug use in secondary school students: study protocol

PubMed Central

2012-01-01

Background Whilst schools provide a potentially appropriate setting for preventing substance use among young people, systematic review evidence suggests that past interventions in this setting have demonstrated limited effectiveness in preventing tobacco, alcohol and other drug use. Interventions that adopt a mental wellbeing approach to prevent substance use offer considerable promise and resilience theory provides one method to impact on adolescent mental well-being. The aim of the proposed study is to examine the efficacy of a resilience intervention in decreasing the tobacco, alcohol and illicit drug use of adolescents. Methods A cluster randomised controlled trial with schools as the unit of randomisation will be undertaken. Thirty two schools in disadvantaged areas will be allocated to either an intervention or a control group. A comprehensive resilience intervention will be implemented, inclusive of explicit program adoption strategies. Baseline surveys will be conducted with students in Grade 7 in both groups and again three years later when the student cohort is in Grade 10. The primary outcome measures will include self-reported tobacco, alcohol, marijuana and other illicit drug use. Comparisons will be made post-test between Grade 10 students in intervention and control schools to determine intervention effectiveness across all measures. Discussion To the authors’ knowledge this is the first randomised controlled trial to evaluate the effectiveness of a comprehensive school-based resilience intervention, inclusive of explicit adoption strategies, in decreasing tobacco, alcohol and illicit drug use of adolescents attending disadvantaged secondary schools. Trial registration ACTRN12611000606987 PMID:23171383

Policies for patient access to clinical data via PHRs: current state and recommendations.

PubMed

Collins, Sarah A; Vawdrey, David K; Kukafka, Rita; Kuperman, Gilad J

2011-12-01

Healthcare delivery organizations are increasingly using online personal health records (PHRs) to provide patients with direct access to their clinical information; however, there may be a lack of consistency in the data made available. We aimed to understand the general use and functionality of PHRs and the organizational policies and decision-making structures for making data available to patients. A cross-sectional survey was administered by telephone structured interview to 21 organizations to determine the types of data made available to patients through PHRs and the presence of explicit governance for PHR data release. Organizations were identified based on a review of the literature, PHR experts, and snowball sampling. Organizations that did not provide patients with electronic access to their data via a PHR were excluded. Interviews were conducted with 17 organizations for a response rate of 81%. Half of the organizations had explicit governance in the form of a written policy that outlined the data types made available to patients. Overall, 88% of the organizations used a committee structure for the decision-making process and included senior management and information services. All organizations sought input from clinicians. Discussion There was considerable variability in the types of clinical data and the time frame for releasing these data to patients. Variability in data release policies may have implications for PHR use and adoption. Future policy activities, such as requirement specification for the latter stages of Meaningful Use, should be leveraged as an opportunity to encourage standardization of functionality and broad deployment of PHRs.

Implicit and explicit self-esteem discrepancies in people with psychogenic nonepileptic seizures.

PubMed

Dimaro, Lian V; Roberts, Nicole A; Moghaddam, Nima G; Dawson, David L; Brown, Ian; Reuber, Markus

2015-05-01

Self-esteem (SE), or one's sense of competence and worth, is reduced in many mental and physical disorders. Low SE is associated with perceived stigma and disability and poor treatment outcomes. The present study examined implicit and explicit SE (automatic and deliberate views about the self) in people with epilepsy and people with psychogenic nonepileptic seizures (PNESs). Discrepancies between implicit SE and explicit SE have been found to correlate with psychological distress in disorders often associated with PNESs but are relatively unexplored in PNESs. We hypothesized that, compared with epilepsy, PNESs would be associated with lower self-reported SE and greater discrepancies between implicit SE and explicit SE. Thirty adults with PNESs, 25 adults with epilepsy, and 31 controls without a history of seizures were asked to complete the Rosenberg Self-esteem Scale as a measure of explicit SE and an Implicit Relational Assessment Procedure as a measure of implicit SE. The State-Trait Anxiety Inventory and Patient Health Questionnaire-15 (a somatic symptom inventory) were also administered. We found significant group differences in explicit (p<0.001) but not implicit SE. Patients with PNESs reported lower SE than the other groups. No group differences were found in implicit SE. Implicit-explicit SE discrepancies were larger in the group with PNESs than in the other groups (p<0.001). Higher frequency of PNESs (but not epileptic seizures) was associated with lower explicit SE (rs=-.83, p<0.01) and greater SE discrepancies (i.e., lower explicit relative to implicit SE; rs=.65, p<0.01). These relationships remained significant when controlling for anxiety and somatization. Patients with PNESs had lower explicit SE than those with epilepsy or healthy controls. In keeping with our expectations, there were greater discrepancies between implicit SE and explicit SE among patients with PNESs than in the other groups. Our results, including the strong relationship between PNES frequency, anxiety, and explicit-implicit SE discrepancies, support the interpretation that PNESs serve to reduce cognitive dissonance, perhaps protecting patients' implicit SE. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.

At the nexus of fire, water and society.

PubMed

Martin, Deborah A

2016-06-05

The societal risks of water scarcity and water-quality impairment have received considerable attention, evidenced by recent analyses of these topics by the 2030 Water Resources Group, the United Nations and the World Economic Forum. What are the effects of fire on the predicted water scarcity and declines in water quality? Drinking water supplies for humans, the emphasis of this exploration, are derived from several land cover types, including forests, grasslands and peatlands, which are vulnerable to fire. In the last two decades, fires have affected the water supply catchments of Denver (CO) and other southwestern US cities, and four major Australian cities including Sydney, Canberra, Adelaide and Melbourne. In the same time period, several, though not all, national, regional and global water assessments have included fire in evaluations of the risks that affect water supplies. The objective of this discussion is to explore the nexus of fire, water and society with the hope that a more explicit understanding of fire effects on water supplies will encourage the incorporation of fire into future assessments of water supplies, into the pyrogeography conceptual framework and into planning efforts directed at water resiliency.This article is part of the themed issue 'The interaction of fire and mankind'. © 2016 The Author(s).

A global research synthesis of HIV and STI biobehavioral risks in female-to-male (FTM) transgender adults

PubMed Central

Reisner, Sari L.; Murchison, Gabriel R.

2016-01-01

There is a growing interest in HIV infection and sexually transmitted infection (STI) disease burden and risk among transgender people globally; however, the majority of work has been conducted with male-to-female (MTF) transgender populations. This research synthesis comprehensively reviews HIV and STI research in female-to-male (FTM) transgender adults. A paucity of research exists about HIV and STIs in FTMs. Only 25 peer-reviewed papers (18 quantitative, 7 qualitative) and 11 ‘grey literature’ reports were identified, most in the U.S. or Canada, that include data identifying HIV and STI risks in FTMs (five with fully laboratory-confirmed HIV and/or STIs, and five with partial laboratory confirmation). Little is known about the sexual and drug use risk behaviors contributing to HIV and STIs in FTMs. Future directions are suggested, including the need for routine surveillance and monitoring of HIV and STIs globally by transgender identity, more standardized sexual risk assessment measures, targeted data collection in lower and middle income countries, and explicit consideration of the rationale for inclusion/exclusion of FTMs in category-based prevention approaches with MSM and transgender people. Implications for research, policy, programming, and interventions are discussed, including the need to address diverse sexual identities, attractions, and behaviors and engage local FTM communities. PMID:26785800

Clinical research informatics and electronic health record data.

PubMed

Richesson, R L; Horvath, M M; Rusincovitch, S A

2014-08-15

The goal of this survey is to discuss the impact of the growing availability of electronic health record (EHR) data on the evolving field of Clinical Research Informatics (CRI), which is the union of biomedical research and informatics. Major challenges for the use of EHR-derived data for research include the lack of standard methods for ensuring that data quality, completeness, and provenance are sufficient to assess the appropriateness of its use for research. Areas that need continued emphasis include methods for integrating data from heterogeneous sources, guidelines (including explicit phenotype definitions) for using these data in both pragmatic clinical trials and observational investigations, strong data governance to better understand and control quality of enterprise data, and promotion of national standards for representing and using clinical data. The use of EHR data has become a priority in CRI. Awareness of underlying clinical data collection processes will be essential in order to leverage these data for clinical research and patient care, and will require multi-disciplinary teams representing clinical research, informatics, and healthcare operations. Considerations for the use of EHR data provide a starting point for practical applications and a CRI research agenda, which will be facilitated by CRI's key role in the infrastructure of a learning healthcare system.

Journal Clubs in Sports Medicine Fellowship Programs: Results From a National Survey and Recommendations for Quality Improvement.

PubMed

Asif, Irfan M; Wiederman, Michael; Kapur, Rahul

2017-11-01

Journal club is a pervasive component of graduate medical education, yet there is no gold standard as to format and logistics. Survey of primary care sports medicine fellowship directors in the United States. Sixty-nine program directors completed the online questionnaire (40% response rate). There were some common aspects to journal club exhibited by a majority of programs, including the general format, required attendance by fellows and expected or required attendance by faculty, the expectation that participants had at least read the article before the meeting, and that meetings occurred during the workday in the work setting without provision of food. There was considerable variation on other aspects, including the objectives of journal club, who had primary responsibility for organizing the session, the criteria for selection of articles, who was invited to attend, and the perceived problems with journal club. This is the first survey investigating the current state of journal club in primary care sports medicine fellowship programs. Several opportunities for educational enhancements exist within journal clubs in primary care sports medicine, including the use of structured tools to guide discussion, providing mechanisms to evaluate the journal club experience as a whole, inviting multidisciplinary team members (eg, statisticians) to discussions, and ensuring that objectives are explicitly stated to participants.

FRAMEWORK FOR ASSESSING RISKS OF ...

EPA Pesticide Factsheets

The Framework for Children's Health Risk Assessment report can serve as a resource on children's health risk assessment and it addresses the need to provide a comprehensive and consistent framework for considering children in risk assessments at EPA. This framework lays out the process, points to existing published sources for more detailed information on life stage-specific considerations, and includes web links to specific online publications and relevant Agency science policy papers, guidelines and guidance. The document emphasizes the need to take into account the potential exposures to environmental agents during preconception and all stages of development and focuses on the relevant adverse health outcomes that may occur as a result of such exposures. This framework is not an Agency guideline, but rather describes the overall structure and the components considered important for children's health risk assessment. The document describes an approach that includes problem formulation, analysis, and risk characterization, and also builds on Agency experience assessing risk to susceptible populations. The problem formulation step focuses on the life stage-specific nature of the analysis to include scoping and screening level questions for hazard characterization, dose response and exposure assessment. The risk characterization step recognizes the need to consider life stage-specific risks and explicitly describes the uncertainties and variability in the d

Decision-making and cognitive abilities: A review of associations between Iowa Gambling Task performance, executive functions, and intelligence.

PubMed

Toplak, Maggie E; Sorge, Geoff B; Benoit, André; West, Richard F; Stanovich, Keith E

2010-07-01

The Iowa Gambling Task (IGT) has been used to study decision-making differences in many different clinical and developmental samples. It has been suggested that IGT performance captures abilities that are separable from cognitive abilities, including executive functions and intelligence. The purpose of the current review was to examine studies that have explicitly examined the relationship between IGT performance and these cognitive abilities. We included 43 studies that reported correlational analyses with IGT performance, including measures of inhibition, working memory, and set-shifting as indices of executive functions, as well as measures of verbal, nonverbal, and full-scale IQ as indices of intelligence. Overall, only a small proportion of the studies reported a statistically significant relationship between IGT performance and these cognitive abilities. The majority of studies reported a non-significant relationship. Of the minority of studies that reported statistically significant effects, effect sizes were, at best, small to modest, and confidence intervals were large, indicating that considerable variability in performance on the IGT is not captured by current measures of executive function and intelligence. These findings highlight the separability between decision-making on the IGT and cognitive abilities, which is consistent with recent conceptualizations that differentiate rationality from intelligence. 2010 Elsevier Ltd. All rights reserved.

Clinical Research Informatics and Electronic Health Record Data

PubMed Central

Horvath, M. M.; Rusincovitch, S. A.

2014-01-01

Summary Objectives The goal of this survey is to discuss the impact of the growing availability of electronic health record (EHR) data on the evolving field of Clinical Research Informatics (CRI), which is the union of biomedical research and informatics. Results Major challenges for the use of EHR-derived data for research include the lack of standard methods for ensuring that data quality, completeness, and provenance are sufficient to assess the appropriateness of its use for research. Areas that need continued emphasis include methods for integrating data from heterogeneous sources, guidelines (including explicit phenotype definitions) for using these data in both pragmatic clinical trials and observational investigations, strong data governance to better understand and control quality of enterprise data, and promotion of national standards for representing and using clinical data. Conclusions The use of EHR data has become a priority in CRI. Awareness of underlying clinical data collection processes will be essential in order to leverage these data for clinical research and patient care, and will require multi-disciplinary teams representing clinical research, informatics, and healthcare operations. Considerations for the use of EHR data provide a starting point for practical applications and a CRI research agenda, which will be facilitated by CRI’s key role in the infrastructure of a learning healthcare system. PMID:25123746

Assessment of the GECKO-A Modeling Tool and Simplified 3D Model Parameterizations for SOA Formation

NASA Astrophysics Data System (ADS)

Aumont, B.; Hodzic, A.; La, S.; Camredon, M.; Lannuque, V.; Lee-Taylor, J. M.; Madronich, S.

2014-12-01

Explicit chemical mechanisms aim to embody the current knowledge of the transformations occurring in the atmosphere during the oxidation of organic matter. These explicit mechanisms are therefore useful tools to explore the fate of organic matter during its tropospheric oxidation and examine how these chemical processes shape the composition and properties of the gaseous and the condensed phases. Furthermore, explicit mechanisms provide powerful benchmarks to design and assess simplified parameterizations to be included 3D model. Nevertheless, the explicit mechanism describing the oxidation of hydrocarbons with backbones larger than few carbon atoms involves millions of secondary organic compounds, far exceeding the size of chemical mechanisms that can be written manually. Data processing tools can however be designed to overcome these difficulties and automatically generate consistent and comprehensive chemical mechanisms on a systematic basis. The Generator for Explicit Chemistry and Kinetics of Organics in the Atmosphere (GECKO-A) has been developed for the automatic writing of explicit chemical schemes of organic species and their partitioning between the gas and condensed phases. GECKO-A can be viewed as an expert system that mimics the steps by which chemists might develop chemical schemes. GECKO-A generates chemical schemes according to a prescribed protocol assigning reaction pathways and kinetics data on the basis of experimental data and structure-activity relationships. In its current version, GECKO-A can generate the full atmospheric oxidation scheme for most linear, branched and cyclic precursors, including alkanes and alkenes up to C25. Assessments of the GECKO-A modeling tool based on chamber SOA observations will be presented. GECKO-A was recently used to design a parameterization for SOA formation based on a Volatility Basis Set (VBS) approach. First results will be presented.

Replication and Pedagogy in the History of Psychology VI: Egon Brunswik on Perception and Explicit Reasoning

NASA Astrophysics Data System (ADS)

Athy, Jeremy; Friedrich, Jeff; Delany, Eileen

2008-05-01

Egon Brunswik (1903 1955) first made an interesting distinction between perception and explicit reasoning, arguing that perception included quick estimates of an object’s size, nearly always resulting in good approximations in uncertain environments, whereas explicit reasoning, while better at achieving exact estimates, could often fail by wide margins. An experiment conducted by Brunswik to investigate these ideas was never published and the only available information is a figure of the results presented in a posthumous book in 1956. We replicated and extended his study to gain insight into the procedures Brunswik used in obtaining his results. Explicit reasoning resulted in fewer errors, yet more extreme ones than perception. Brunswik’s graphical analysis of the results led to different conclusions, however, than did a modern statistically-based analysis.

Development and necessary norms of reasoning

PubMed Central

Markovits, Henry

2014-01-01

The question of whether reasoning can, or should, be described by a single normative model is an important one. In the following, I combine epistemological considerations taken from Piaget’s notion of genetic epistemology, a hypothesis about the role of reasoning in communication and developmental data to argue that some basic logical principles are in fact highly normative. I argue here that explicit, analytic human reasoning, in contrast to intuitive reasoning, uniformly relies on a form of validity that allows distinguishing between valid and invalid arguments based on the existence of counterexamples to conclusions. PMID:24904501

Anthropology and affect: a consideration of the idiosyncratic dimension of human behaviour.

PubMed

Izmirlian, H

1977-01-01

In this paper a theoretical perspective is presented in which affect occupies a central position and behaviour is viewed in terms of different degrees of affective expression. Such behaviour is conceptualized in terms of three models: a structural model, a rational model and a psychological model. While the first two models are frequently encountered in the literature, the psychological model has not received explicit formulation, although, as shown here, it is crucial in understanding certain forms of idiosyncratic behaviour that have political and social relevance.

Robust root clustering for linear uncertain systems using generalized Lyapunov theory

NASA Technical Reports Server (NTRS)

Yedavalli, R. K.

1993-01-01

Consideration is given to the problem of matrix root clustering in subregions of a complex plane for linear state space models with real parameter uncertainty. The nominal matrix root clustering theory of Gutman & Jury (1981) using the generalized Liapunov equation is extended to the perturbed matrix case, and bounds are derived on the perturbation to maintain root clustering inside a given region. The theory makes it possible to obtain an explicit relationship between the parameters of the root clustering region and the uncertainty range of the parameter space.

Solvent electronic polarization effects on a charge transfer excitation studied by the mean-field QM/MM method

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

Nakano, Hiroshi; Elements Strategy Initiative for Catalysts and Batteries, Kyoto University, Kyoto 615-8245

2015-12-31

Electronic polarization effects of a medium can have a significant impact on a chemical reaction in condensed phases. We discuss the effects on the charge transfer excitation of a chromophore, N,N-dimethyl-4-nitroaniline, in various solvents using the mean-field QM/MM method with a polarizable force field. The results show that the explicit consideration of the solvent electronic polarization effects is important especially for a solvent with a low dielectric constant when we study the solvatochromism of the chromophore.

Tunnelling in Dante's Inferno

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

Furuuchi, Kazuyuki; Sperling, Marcus, E-mail: kazuyuki.furuuchi@manipal.edu, E-mail: marcus.sperling@univie.ac.at

2017-05-01

We study quantum tunnelling in Dante's Inferno model of large field inflation. Such a tunnelling process, which will terminate inflation, becomes problematic if the tunnelling rate is rapid compared to the Hubble time scale at the time of inflation. Consequently, we constrain the parameter space of Dante's Inferno model by demanding a suppressed tunnelling rate during inflation. The constraints are derived and explicit numerical bounds are provided for representative examples. Our considerations are at the level of an effective field theory; hence, the presented constraints have to hold regardless of any UV completion.

Legal Barriers to Adolescent Participation in Research About HIV and Other Sexually Transmitted Infections

PubMed Central

Moore, Quianta L.; Paul, Mary E.; McGuire, Amy L.

2016-01-01

Whether adolescents can participate in clinical trials of pharmacologic therapies for HIV prevention, such as preexposure prophylaxis, without parental permission hinges on state minor consent laws. Very few of these laws explicitly authorize adolescents to consent to preventive services for HIV and other sexually transmitted infections. Unclear state laws may lead to research cessation. We have summarized legal, ethical, and policy considerations related to adolescents’ participation in HIV and sexually transmitted infection prevention research in the United States, and we have explored strategies for facilitating adolescents’ access. PMID:26562103

Papers on Program Testing,

DTIC Science & Technology

1979-01-01

tractability for scientific analysis. Although much remains to be learned about mutation as a testing tool, there is a considerable body of written material...explicitly address classifications (2) may not have been affected at all! In general, the and (3) in this article , except to point out that even relative...34 ARTICLE B=B’B C IN CACM 1971). C=C*02 INTEGER AiN),N.F D=B+C INTEGER M.NS.R.I.J.W IF (A.NE.D) GOTO 200 MI PRINT 150 NS=N 150 FORMATIIH .RIGHT ANGLED

Size-dependent axial instability of microtubules surrounded by cytoplasm of a living cell based on nonlocal strain gradient elasticity theory.

PubMed

Sahmani, S; Aghdam, M M

2017-06-07

Microtubules including tubulin heterodimers arranging in a parallel shape of cylindrical hollow plays an important role in the mechanical stiffness of a living cell. In the present study, the nonlocal strain gradient theory of elasticity including simultaneously the both nonlocality and strain gradient size dependency is put to use within the framework of a refined orthotropic shell theory with hyperbolic distribution of shear deformation to analyze the size-dependent buckling and postbuckling characteristics of microtubules embedded in cytoplasm under axial compressive load. The non-classical governing differential equations are deduced via boundary layer theory of shell buckling incorporating the nonlinear prebuckling deformation and microtubule-cytoplasm interaction in the living cell environment. Finally, with the aid of a two-stepped perturbation solution methodology, the explicit analytical expressions for nonlocal strain gradient stability paths of axially loaded microtubules are achieved. It is illustrated that by taking the nonlocal size effect into consideration, the critical buckling load of microtubule and its maximum deflection associated with the minimum postbuckling load decreases, while the strain gradient size dependency causes to increase them. Copyright © 2017 Elsevier Ltd. All rights reserved.

Mainstreaming gender in integrated water resources management: the case of Zimbabwe

NASA Astrophysics Data System (ADS)

Manase, G.; Ndamba, J.; Makoni, F.

Zimbabwe embarked on a water sector reform programme in 1995. Two goals of the water reform were to broaden women’s access to water and to enhance their participation in water management. This paper analyses how gender was addressed at the national and institutional levels and in the water reform process, paying particular attention on how strategic gender needs were addressed in the process and the resultant policies and Acts. The results show that although the government of Zimbabwe has made considerable progress in mainstreaming gender at the ministerial level, departments which are involved in the actual implementation of water programmes do not have clear gender policies. Therefore although gender equity was one of the main goals of the water reform, most poor women and men were not involved in the consultations. Consequently neither the new Water Act nor the Zimbabwe National Water Authority (ZINWA) Act addresses gender in explicit terms. Strategic gender needs are not addressed at all. It is recommended that all institutions in the water sector, including NGOs, should have clear gender policies, include a gender perspective in their organisation culture and practices and address strategic gender needs through training, education and supporting productive use of water.

Consistent simulation of direct-photon production in hadron collisions including associated two-jet production

NASA Astrophysics Data System (ADS)

Odaka, Shigeru; Kurihara, Yoshimasa

2016-05-01

We have developed an event generator for direct-photon production in hadron collisions, including associated 2-jet production in the framework of the GR@PPA event generator. The event generator consistently combines γ + 2-jet production processes with the lowest-order γ + jet and photon-radiation (fragmentation) processes from quantum chromodynamics (QCD) 2-jet production using a subtraction method. The generated events can be fed to general-purpose event generators to facilitate the addition of hadronization and decay simulations. Using the obtained event information, we can simulate photon isolation and hadron-jet reconstruction at the particle (hadron) level. The simulation reasonably reproduces measurement data obtained at the large hadron collider (LHC) concerning not only the inclusive photon spectrum, but also the correlation between the photon and jet. The simulation implies that the contribution of the γ + 2-jet is very large, especially in low photon-pT ( ≲ 50 GeV) regions. Discrepancies observed at low pT, although marginal, may indicate the necessity for the consideration of further higher-order processes. Unambiguous particle-level definition of the photon-isolation condition for the signal events is desired to be given explicitly in future measurements.

Quantum mechanical prediction of four-phonon scattering rates and reduced thermal conductivity of solids

NASA Astrophysics Data System (ADS)

Feng, Tianli; Ruan, Xiulin

2016-01-01

Recently, first principle-based predictions of lattice thermal conductivity κ from perturbation theory have achieved significant success. However, it only includes three-phonon scattering due to the assumption that four-phonon and higher-order processes are generally unimportant. Also, directly evaluating the scattering rates of four-phonon and higher-order processes has been a long-standing challenge. In this work, however, we have developed a formalism to explicitly determine quantum mechanical scattering probability matrices for four-phonon scattering in the full Brillouin zone, and by mitigating the computational challenge we have directly calculated four-phonon scattering rates. We find that four-phonon scattering rates are comparable to three-phonon scattering rates at medium and high temperatures, and they increase quadratically with temperature. As a consequence, κ of Lennard-Jones argon is reduced by more than 60% at 80 K when four-phonon scattering is included. Also, in less anharmonic materials—diamond, silicon, and germanium—κ is still reduced considerably at high temperature by four-phonon scattering by using the classical Tersoff potentials. Also, the thermal conductivity of optical phonons is dominated by the fourth- and higher-orders phonon scattering even at low temperature.

Evidence of Microbial Regulation of Biogeochemical Cycles from a Study on Methane Flux and Land Use Change

PubMed Central

Nazaries, Loïc; Pan, Yao; Bodrossy, Levente; Baggs, Elizabeth M.; Millard, Peter; Murrell, J. Colin

2013-01-01

Microbes play an essential role in ecosystem functions, including carrying out biogeochemical cycles, but are currently considered a black box in predictive models and all global biodiversity debates. This is due to (i) perceived temporal and spatial variations in microbial communities and (ii) lack of ecological theory explaining how microbes regulate ecosystem functions. Providing evidence of the microbial regulation of biogeochemical cycles is key for predicting ecosystem functions, including greenhouse gas fluxes, under current and future climate scenarios. Using functional measures, stable-isotope probing, and molecular methods, we show that microbial (community diversity and function) response to land use change is stable over time. We investigated the change in net methane flux and associated microbial communities due to afforestation of bog, grassland, and moorland. Afforestation resulted in the stable and consistent enhancement in sink of atmospheric methane at all sites. This change in function was linked to a niche-specific separation of microbial communities (methanotrophs). The results suggest that ecological theories developed for macroecology may explain the microbial regulation of the methane cycle. Our findings provide support for the explicit consideration of microbial data in ecosystem/climate models to improve predictions of biogeochemical cycles. PMID:23624469

Recruitment of Anterior and Posterior Structures in Lexical-Semantic Processing: An fMRI Study Comparing Implicit and Explicit Tasks

ERIC Educational Resources Information Center

Ruff, Ilana; Blumstein, Sheila E.; Myers, Emily B.; Hutchison, Emmette

2008-01-01

Previous studies examining explicit semantic processing have consistently shown activation of the left inferior frontal gyrus (IFG). In contrast, implicit semantic processing tasks have shown activation in posterior areas including the superior temporal gyrus (STG) and the middle temporal gyrus (MTG) with less consistent activation in the IFG.…

Impact of Explicit Vocabulary Instruction on Writing Achievement of Upper-Intermediate EFL Learners

ERIC Educational Resources Information Center

Solati-Dehkordi, Seyed Amir; Salehi, Hadi

2016-01-01

Studying explicit vocabulary instruction effects on improving L2 learners' writing skill and their short and long-term retention is the purpose of the present study. To achieve the mentioned goal, a fill-in-the-blank test including 36 single words and 60 lexical phrases were administrated to 30 female upper-intermediate EFL learners. The EFL…

The Effects of Explicit Reading Strategy Instruction and Cooperative Learning on Reading Comprehension in Fourth Grade Students

ERIC Educational Resources Information Center

Lencioni, Gina M.

2013-01-01

The purpose of this study was to investigate the effects of explicit direct instruction and cooperative learning on reading comprehension in fourth grade students. A quasi-experimental design was used. There were six cognitive and three affective measures used to collect quantitative data. Cognitive measures included California State Test scores,…

A numerical algorithm for the explicit calculation of SU(N) and SL(N,C) Clebsch-Gordan coefficients

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

Alex, Arne; Delft, Jan von; Kalus, Matthias

2011-02-15

We present an algorithm for the explicit numerical calculation of SU(N) and SL(N,C) Clebsch-Gordan coefficients, based on the Gelfand-Tsetlin pattern calculus. Our algorithm is well suited for numerical implementation; we include a computer code in an appendix. Our exposition presumes only familiarity with the representation theory of SU(2).

Making Grammar Explicit in the Classroom: An Illustration Using the Spanish Subjunctive.

ERIC Educational Resources Information Center

Kilroe, Patricia

1988-01-01

It is proposed that explicit explanations of grammar concepts in the first language can be useful in teaching the related structures in a second language. The example used is that of the subjunctive mood, taught first in English and then in Spanish. Specific procedures for presenting the concept in English are outlined, including a set of…

Re-Examining the Role of Explicit Instruction and Input Flood on the Acquisition of Spanish Discourse Markers

ERIC Educational Resources Information Center

Hernandez, Todd A.

2011-01-01

Expanding on the studies of Hernandez (2008) and de la Fuente (2009), this investigation examines the combined effect of explicit instruction (EI) and input flood (IF) vs. IF alone on students' use of discourse markers to narrate a past event. Participants included 91 English-speaking adults enrolled in fourth-semester college Spanish courses,…

A Multi-Year Program Developing an Explicit Reflective Pedagogy for Teaching Pre-Service Teachers the Nature of Science by Ostention

ERIC Educational Resources Information Center

Smith, Mike U.; Scharmann, Lawrence

2008-01-01

This investigation delineates a multi-year action research agenda designed to develop an instructional model for teaching the nature of science (NOS) to preservice science teachers. Our past research strongly supports the use of explicit reflective instructional methods, which includes Thomas Kuhn's notion of learning by ostention and treating…

Comparative Analysis of Classroom Speech in Upper Level Spanish College Courses: A Social Constructivist View

ERIC Educational Resources Information Center

Rondon-Pari, Graziela

2011-01-01

This study reflects a social constructivist theoretical framework in which the zone of proximal development (ZPD) is a central element, as two teaching approaches, communicative language teaching (CLT) and explicit focus on form (FonF) are examined. Research questions include: Are CLT and explicit FonF conducive to reaching the ZPD? Is there a…

Understanding relevance of health research: considerations in the context of research impact assessment.

PubMed

Dobrow, Mark J; Miller, Fiona A; Frank, Cy; Brown, Adalsteinn D

2017-04-17

With massive investment in health-related research, above and beyond investments in the management and delivery of healthcare and public health services, there has been increasing focus on the impact of health research to explore and explain the consequences of these investments and inform strategic planning. Relevance is reflected by increased attention to the usability and impact of health research, with research funders increasingly engaging in relevance assessment as an input to decision processes. Yet, it is unclear whether relevance is a synonym for or predictor of impact, a necessary condition or stage in achieving it, or a distinct aim of the research enterprise. The main aim of this paper is to improve our understanding of research relevance, with specific objectives to (1) unpack research relevance from both theoretical and practical perspectives, and (2) outline key considerations for its assessment. Our approach involved the scholarly strategy of review and reflection. We prepared a draft paper based on an exploratory review of literature from various fields, and gained from detailed and insightful analysis and critique at a roundtable discussion with a group of key health research stakeholders. We also solicited review and feedback from a small sample of expert reviewers. Research relevance seems increasingly important in justifying research investments and guiding strategic research planning. However, consideration of relevance has been largely tacit in the health research community, often depending on unexplained interpretations of value, fit and potential for impact. While research relevance seems a necessary condition for impact - a process or component of efforts to make rigorous research usable - ultimately, relevance stands apart from research impact. Careful and explicit consideration of research relevance is vital to gauge the overall value and impact of a wide range of individual and collective research efforts and investments. To improve understanding, this paper outlines four key considerations, including how research relevance assessments (1) orientate to, capture and compare research versus non-research sources, (2) consider both instrumental versus non-instrumental uses of research, (3) accommodate dynamic temporal-shifting perspectives on research, and (4) align with an intersubjective understanding of relevance.

Delay and death-thought accessibility: a meta-analysis.

PubMed

Steinman, Christopher T; Updegraff, John A

2015-12-01

The dual-process component of Terror Management Theory (TMT) proposes that different types of threats lead to increases in death-thought accessibility (DTA) after different delay intervals. Experimental studies of terror management threats' effect on DTA were collected and coded for their use of explicitly death-related (vs. not explicitly death-related) threats, and for their use of delay and task-switching during the delay. Results reveal that studies using death-related threats achieved larger DTA effect-sizes when they included more task-switching or a longer delay between the threat and the DTA measurement. In contrast, studies using threats that were not explicitly death-related achieved smaller DTA effect-sizes when they included more task-switching between the threat and the DTA measurement. These findings provide partial support for the dual-process component's predictions regarding delay and DTA. Limitations and future directions are discussed. © 2015 by the Society for Personality and Social Psychology, Inc.

Solution Methods for Certain Evolution Equations

NASA Astrophysics Data System (ADS)

Vega-Guzman, Jose Manuel

Solution methods for certain linear and nonlinear evolution equations are presented in this dissertation. Emphasis is placed mainly on the analytical treatment of nonautonomous differential equations, which are challenging to solve despite the existent numerical and symbolic computational software programs available. Ideas from the transformation theory are adopted allowing one to solve the problems under consideration from a non-traditional perspective. First, the Cauchy initial value problem is considered for a class of nonautonomous and inhomogeneous linear diffusion-type equation on the entire real line. Explicit transformations are used to reduce the equations under study to their corresponding standard forms emphasizing on natural relations with certain Riccati(and/or Ermakov)-type systems. These relations give solvability results for the Cauchy problem of the parabolic equation considered. The superposition principle allows to solve formally this problem from an unconventional point of view. An eigenfunction expansion approach is also considered for this general evolution equation. Examples considered to corroborate the efficacy of the proposed solution methods include the Fokker-Planck equation, the Black-Scholes model and the one-factor Gaussian Hull-White model. The results obtained in the first part are used to solve the Cauchy initial value problem for certain inhomogeneous Burgers-type equation. The connection between linear (the Diffusion-type) and nonlinear (Burgers-type) parabolic equations is stress in order to establish a strong commutative relation. Traveling wave solutions of a nonautonomous Burgers equation are also investigated. Finally, it is constructed explicitly the minimum-uncertainty squeezed states for quantum harmonic oscillators. They are derived by the action of corresponding maximal kinematical invariance group on the standard ground state solution. It is shown that the product of the variances attains the required minimum value only at the instances that one variance is a minimum and the other is a maximum, when the squeezing of one of the variances occurs. Such explicit construction is possible due to the relation between the diffusion-type equation studied in the first part and the time-dependent Schrodinger equation. A modication of the radiation field operators for squeezed photons in a perfect cavity is also suggested with the help of a nonstandard solution of Heisenberg's equation of motion.

Spatially Explicit Simulation of Mesotopographic Controls on Peatland Hydrology and Carbon Fluxes

NASA Astrophysics Data System (ADS)

Sonnentag, O.; Chen, J. M.; Roulet, N. T.

2006-12-01

A number of field carbon flux measurements, paleoecological records, and model simulations have acknowledged the importance of northern peatlands in terrestrial carbon cycling and methane emissions. An important parameter in peatlands that influences both net primary productivity, the net gain of carbon through photosynthesis, and decomposition under aerobic and anaerobic conditions, is the position of the water table. Biological and physical processes involved in peatland carbon dynamics and their hydrological controls operate at different spatial scales. The highly variable hydraulic characteristics of the peat profile and the overall shape of the peat body as defined by its surface topography at the mesoscale (104 m2) are of major importance for peatland water table dynamics. Common types of peatlands include bogs with a slightly domed centre. As a result of the convex profile, their water supply is restricted to atmospheric inputs, and water is mainly shed by shallow subsurface flow. From a modelling perspective the influence of mesotopographic controls on peatland hydrology and thus carbon balance requires that process-oriented models that examine the links between peatland hydrology, ecosystem functioning, and climate must incorporate some form of lateral subsurface flow consideration. Most hydrological and ecological modelling studies in complex terrain explicitly account for the topographic controls on lateral subsurface flow through digital elevation models. However, modelling studies in peatlands often employ simple empirical parameterizations of lateral subsurface flow, neglecting the influence of peatlands low relief mesoscale topography. Our objective is to explicitly simulate the mesotopographic controls on peatland hydrology and carbon fluxes using the Boreal Ecosystem Productivity Simulator (BEPS) adapted to northern peatlands. BEPS is a process-oriented ecosystem model in a remote sensing framework that takes into account peatlands multi-layer canopy through vertically stratified mapped leaf area index. Model outputs are validated against multi-year measurements taken at an eddy-covariance flux tower located within Mer Bleue bog, a typical raised bog near Ottawa, Ontario, Canada. Model results for seasonal water table dynamics and evapotranspiration at daily time steps in 2003 are in good agreement with measurements with R2=0.74 and R2=0.79, respectively, and indicate the suitability of our pursued approach.

Lifestyle Approaches for People With Intellectual Disabilities: A Systematic Multiple Case Analysis.

PubMed

Steenbergen, Henderika Annegien; Van der Schans, Cees P; Van Wijck, Ruud; De Jong, Johan; Waninge, Aly

2017-11-01

Health care organizations supporting individuals with intellectual disabilities (IDs) carry out a range of interventions to support and improve a healthy lifestyle. However, it is difficult to implement an active and healthy lifestyle into daily support. The presence of numerous intervention components, multiple levels of influence, and the explicit use of theory are factors that are considered to be essential for implementation in practice. A comprehensive written lifestyle policy provides for sustainability of a lifestyle approach. It is unknown to what extent these crucial factors for successful implementation are taken into consideration by health care organizations supporting this population. To analyze the intervention components, levels of influence, explicit use of theory, and conditions for sustainability of currently used lifestyle interventions within lifestyle approaches aiming at physical activity and nutrition in health care organizations supporting people with ID. In this descriptive multiple case study of 9 health care organizations, qualitative data of the lifestyle approaches with accompanying interventions and their components were compiled with a newly developed online inventory form. From 9 health care organizations, 59 interventions were included, of which 31% aimed to improve physical activity, 10% nutrition, and 59% a combination of both. Most (49%) interventions aimed at the educational component and less at daily (19%) and generic activities (16%) and the evaluation component (16%). Most interventions targeted individuals with ID and the professionals whereas social levels were underrepresented. Although 52% of the interventions were structurally embedded, only 10 of the 59 interventions were theory-driven. Health care organizations could improve their lifestyle approaches by using an explicit theoretical basis by expanding the current focus of the interventions that primarily concentrate on their clients and professionals toward also targeting the social and external environment as well as the introduction of a written lifestyle policy. This policy should encompass all interventions and should be the responsibility of those in the organization working with individuals with ID. In conclusion, comprehensive, integrated, and theory-driven approaches at multiple levels should be promoted. Copyright © 2017 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.

Acceptability of Sexually Explicit Images in HIV Prevention Messages Targeting Men Who Have Sex With Men.

PubMed

Iantaffi, Alex; Wilkerson, J Michael; Grey, Jeremy A; Rosser, B R Simon

2015-01-01

Sexually explicit media (SEM) have been used in HIV-prevention advertisements to engage men who have sex with men (MSM) and to communicate content. These advertisements exist within larger discourses, including a dominant heteronormative culture and a growing homonormative culture. Cognizant of these hegemonic cultures, this analysis examined the acceptable level of sexual explicitness in prevention advertisements. Seventy-nine MSM participated in 13 online focus groups, which were part of a larger study of SEM. Three macro themes-audience, location, and community representation-emerged from the analysis, as did the influence of homonormativity on the acceptability of SEM in HIV-prevention messages.

Acceptability of Sexually Explicit Images in HIV Prevention Messages Targeting Men Who Have Sex with Men

PubMed Central

Iantaffi, Alex; Wilkerson, J. Michael; Grey, Jeremy A.; Rosser, B. R. Simon

2014-01-01

Sexually explicit media (SEM) have been used in HIV-prevention advertisements to engage men who have sex with men (MSM), and to communicate content. These advertisements exist within larger discourses, including a dominant heternormative culture, and a growing homonormative culture. Cognizant of these hegemonic cultures, this analysis examined the acceptable level of sexual explicitness in prevention advertisements. 79 MSM participated in 13 online focus groups, which were part of a larger study of SEM. Three macro-themes—audience, location and community representation—emerged from the analysis, as did the influence of homonormativity on the acceptability of SEM in HIV-prevention messages. PMID:26075485

International trade versus public health during the FCTC negotiations, 1999-2003.

PubMed

Mamudu, Hadii M; Hammond, Ross; Glantz, Stanton A

2011-01-01

To examine why the Framework Convention on Tobacco Control did not include an explicit trade provision and delineate the central arguments in the debate over trade provision during the negotiations. Triangulate interviews with participants in the FCTC negotiations, the FCTC negotiations documents, and tobacco industry documents. An explicit FCTC trade provision on relation between international trade and public health became a contentious issue during the negotiations. As a result, two conflicting positions, health-over-trade and opposition to health-over-trade emerged. Opposition to explicit trade language giving health priority was by both tobacco industry and countries that generally supported strong FCTC provisions because of concerns over 'disguised protectionism' and setting a precedent whereby governments could forfeit their obligations under pre-existing treaties. Owing to lack of consensus among political actors involved in the negotiations, a compromise position eliminating any mention of trade emerged, which was predicated on belief among some in the public health community that public health would prevail in future trade versus health conflicts. The absence of an explicit FCTC trade provision was due to a political compromise rather than the impact of international trade agreements and decisions on public health and lack of consensus among health advocates. This failure to include an explicit trade provision in the FCTC suggests that the public health community should become more involved in trade and health issues at all levels of governance and press the FCTC Conference of the Parties for clarification of this critical issue.

Explicit Oral Narrative Intervention for Students with Williams Syndrome

PubMed Central

Diez-Itza, Eliseo; Martínez, Verónica; Pérez, Vanesa; Fernández-Urquiza, Maite

2018-01-01

Narrative skills play a crucial role in organizing experience, facilitating social interaction and building academic discourse and literacy. They are at the interface of cognitive, social, and linguistic abilities related to school engagement. Despite their relative strengths in social and grammatical skills, students with Williams syndrome (WS) do not show parallel cognitive and pragmatic performance in narrative generation tasks. The aim of the present study was to assess retelling of a TV cartoon tale and the effect of an individualized explicit instruction of the narrative structure. Participants included eight students with WS who attended different special education levels. Narratives were elicited in two sessions (pre and post intervention), and were transcribed, coded and analyzed using the tools of the CHILDES Project. Narratives were coded for productivity and complexity at the microstructure and macrostructure levels. Microstructure productivity (i.e., length of narratives) included number of utterances, clauses, and tokens. Microstructure complexity included mean length of utterances, lexical diversity and use of discourse markers as cohesive devices. Narrative macrostructure was assessed for textual coherence through the Pragmatic Evaluation Protocol for Speech Corpora (PREP-CORP). Macrostructure productivity and complexity included, respectively, the recall and sequential order of scenarios, episodes, events and characters. A total of four intervention sessions, lasting approximately 20 min, were delivered individually once a week. This brief intervention addressed explicit instruction about the narrative structure and the use of specific discourse markers to improve cohesion of story retellings. Intervention strategies included verbal scaffolding and modeling, conversational context for retelling the story and visual support with pictures printed from the cartoon. Results showed significant changes in WS students’ retelling of the story, both at macro- and microstructure levels, when assessed following a 2-week interval. Outcomes were better in microstructure than in macrostructure, where sequential order (i.e., complexity) did not show significant improvement. These findings are consistent with previous research supporting the use of explicit oral narrative intervention with participants who are at risk of school failure due to communication impairments. Discussion focuses on how assessment and explicit instruction of narrative skills might contribute to effective intervention programs enhancing school engagement in WS students. PMID:29379455

Framing health for land-use planning legislation: A qualitative descriptive content analysis.

PubMed

Harris, Patrick; Kent, Jennifer; Sainsbury, Peter; Thow, Anne Marie

2016-01-01

Framing health as a relevant policy issue for other sectors is not well understood. A recent review of the New South Wales (Australia) land-use planning system resulted in the drafting of legislation with an internationally unprecedented focus on human health. We apply a political science approach to investigate the question 'how and to what extent were health and wider issues framed in submissions to the review?' We investigated a range of stakeholder submissions including health focussed agencies (n = 31), purposively identified key stakeholders with influence on the review (n = 24), and a random sample of other agencies and individuals (n = 47). Using qualitative descriptive analysis we inductively coded for the term 'health' and sub-categories. We deductively coded for 'wider concerns' using a locally endorsed 'Healthy Urban Development Checklist'. Additional inductive analysis uncovered further 'wider concerns'. Health was explicitly identified as a relevant issue for planning policy only in submissions by health-focussed agencies. This framing concerned the new planning system promoting and protecting health as well as connecting health to wider planning concerns including economic issues, transport, public open space and, to a slightly lesser extent, environmental sustainability. Key stakeholder and other agency submissions focussed on these and other wider planning concerns but did not mention health in detail. Health agency submissions did not emphasise infrastructure, density or housing as explicitly as others. Framing health as a relevant policy issue has the potential to influence legislative change governing the business of other sectors. Without submissions from health agencies arguing the importance of having health as an objective in the proposed legislation it is unlikely health considerations would have gained prominence in the draft bill. The findings have implications for health agency engagement with legislative change processes and beyond in land use planning. Copyright © 2015 Elsevier Ltd. All rights reserved.

SPIN CORRELATIONS OF THE FINAL LEPTONS IN THE TWO-PHOTON PROCESSES γγ → e+e-, μ+μ-, τ+τ-

NASA Astrophysics Data System (ADS)

Lyuboshitz, Valery V.; Lyuboshitz, Vladimir L.

2014-12-01

The spin structure of the process γγ → e+e- is theoretically investigated. It is shown that, if the primary photons are unpolarized, the final electron and positron are unpolarized as well but their spins are strongly correlated. For the final (e+e-) system, explicit expressions for the components of the correlation tensor are derived, and the relative fractions of singlet and triplet states are found. It is demonstrated that in the process γγ → e+e- one of the Bell-type incoherence inequalities for the correlation tensor components is always violated and, thus, spin correlations of the electron and positron in this process have the strongly pronounced quantum character. Analogous consideration can be wholly applied as well to the two-photon processes γγ → μ+μ- and γγ → τ+τ-, which become possible at considerably higher energies.

Topology optimization for nonlinear dynamic problems: Considerations for automotive crashworthiness

NASA Astrophysics Data System (ADS)

Kaushik, Anshul; Ramani, Anand

2014-04-01

Crashworthiness of automotive structures is most often engineered after an optimal topology has been arrived at using other design considerations. This study is an attempt to incorporate crashworthiness requirements upfront in the topology synthesis process using a mathematically consistent framework. It proposes the use of equivalent linear systems from the nonlinear dynamic simulation in conjunction with a discrete-material topology optimizer. Velocity and acceleration constraints are consistently incorporated in the optimization set-up. Issues specific to crash problems due to the explicit solution methodology employed, nature of the boundary conditions imposed on the structure, etc. are discussed and possible resolutions are proposed. A demonstration of the methodology on two-dimensional problems that address some of the structural requirements and the types of loading typical of frontal and side impact is provided in order to show that this methodology has the potential for topology synthesis incorporating crashworthiness requirements.

Consideration and Checkboxes: Incorporating Ethics and Science into the 3Rs

PubMed Central

Landi, Margaret S; Shriver, Adam J; Mueller, Anne

2015-01-01

Members of the research community aim to both produce high-quality research and ensure that harm is minimized in animals. The primary means of ensuring these goals are both met is the 3Rs framework of replacement, reduction, and refinement. However, some approaches to the 3Rs may result in a ‘check box mentality’ in which IACUC members, researchers, administrators, and caretakers check off a list of tasks to evaluate a protocol. We provide reasons for thinking that the 3Rs approach could be enhanced with more explicit discussion of the ethical assumptions used to arrive at an approved research protocol during IACUC review. Here we suggest that the notion of moral considerability, and all of the related issues it gives rise to, should be incorporated into IACUC discussions of 3Rs deliberations during protocol review to ensure that animal wellbeing is enhanced within the constraints of scientific investigation. PMID:25836970

Peristalsis of nonconstant viscosity Jeffrey fluid with nanoparticles

NASA Astrophysics Data System (ADS)

Alvi, N.; Latif, T.; Hussain, Q.; Asghar, S.

Mixed convective peristaltic activity of variable viscosity nanofluids is addressed. Unlike the conventional consideration of constant viscosity; the viscosity is taken as temperature dependent. Constitutive relations for linear viscoelastic Jeffrey fluid are employed and uniform magnetic field is applied in the transverse direction. For nanofluids, the formulation is completed in presence of Brownian motion, thermophoresis, viscous dissipation and Joule heating. Consideration of temperature dependence of viscosity is not a choice but the realistic requirement of the wall temperature and the heat generated due to the viscous dissipation. Well established large wavelength and small Reynolds number approximations are invoked. Non-linear coupled system is analytically solved for the convergent series solutions identifying the interval of convergence explicitly. A comparative study between analytical and numerical solution is made for certainty. Influence of the parameters undertaken for the description of the problem is pointed out and its physics explained.

An ordinal classification approach for CTG categorization.

PubMed

Georgoulas, George; Karvelis, Petros; Gavrilis, Dimitris; Stylios, Chrysostomos D; Nikolakopoulos, George

2017-07-01

Evaluation of cardiotocogram (CTG) is a standard approach employed during pregnancy and delivery. But, its interpretation requires high level expertise to decide whether the recording is Normal, Suspicious or Pathological. Therefore, a number of attempts have been carried out over the past three decades for development automated sophisticated systems. These systems are usually (multiclass) classification systems that assign a category to the respective CTG. However most of these systems usually do not take into consideration the natural ordering of the categories associated with CTG recordings. In this work, an algorithm that explicitly takes into consideration the ordering of CTG categories, based on binary decomposition method, is investigated. Achieved results, using as a base classifier the C4.5 decision tree classifier, prove that the ordinal classification approach is marginally better than the traditional multiclass classification approach, which utilizes the standard C4.5 algorithm for several performance criteria.

When should psychiatrists seek criminal prosecution of assaultive psychiatric inpatients?

PubMed

Ho, Justin; Ralston, D Christopher; McCullough, Laurence B; Coverdale, John H

2009-08-01

This Open Forum commentary reviews the ethical considerations relevant to the question of prosecuting assaultive psychiatric patients, with particular attention to the significance that should be attached to the arguments generated by those considerations. A comprehensive literature search was conducted incorporating the terms "assaultive patients," "ethics," "psychiatric inpatients," and "law." The literature of professional medical ethics was applied to identify relevant domains of ethical argument. Five domains were identified: fiduciary obligations of physicians to assaultive and other patients; obligations to staff members; professional virtues of compassion, self-sacrifice, and self-effacement; retributive justice; and the patient's right to confidentiality. The content of each domain is explained, and guidance is provided on how to assess the relative strengths of ethical argument within each domain. All five domains must be explicitly addressed in order to make ethically disciplined judgments about whether to seek prosecution. A distinctive feature of this ethical analysis is the central importance of the professional virtues.

Value-Based Requirements Traceability: Lessons Learned

NASA Astrophysics Data System (ADS)

Egyed, Alexander; Grünbacher, Paul; Heindl, Matthias; Biffl, Stefan

Traceability from requirements to code is mandated by numerous software development standards. These standards, however, are not explicit about the appropriate level of quality of trace links. From a technical perspective, trace quality should meet the needs of the intended trace utilizations. Unfortunately, long-term trace utilizations are typically unknown at the time of trace acquisition which represents a dilemma for many companies. This chapter suggests ways to balance the cost and benefits of requirements traceability. We present data from three case studies demonstrating that trace acquisition requires broad coverage but can tolerate imprecision. With this trade-off our lessons learned suggest a traceability strategy that (1) provides trace links more quickly, (2) refines trace links according to user-defined value considerations, and (3) supports the later refinement of trace links in case the initial value consideration has changed over time. The scope of our work considers the entire life cycle of traceability instead of just the creation of trace links.

On Feeling Torn About One’s Sexuality

PubMed Central

Windsor-Shellard, Ben

2014-01-01

Three studies offer novel evidence addressing the consequences of explicit–implicit sexual orientation (SO) ambivalence. In Study 1, self-identified straight females completed explicit and implicit measures of SO. The results revealed that participants with greater SO ambivalence took longer responding to explicit questions about their sexual preferences, an effect moderated by the direction of ambivalence. Study 2 replicated this effect using a different paradigm. Study 3 included self-identified straight and gay female and male participants; participants completed explicit and implicit measures of SO, plus measures of self-esteem and affect regarding their SO. Among straight participants, the response time results replicated the findings of Studies 1 and 2. Among gay participants, trends suggested that SO ambivalence influenced time spent deliberating on explicit questions relevant to sexuality, but in a different way. Furthermore, the amount and direction of SO ambivalence was related to self-esteem. PMID:24972940

Group-based differences in anti-aging bias among medical students.

PubMed

Ruiz, Jorge G; Andrade, Allen D; Anam, Ramanakumar; Taldone, Sabrina; Karanam, Chandana; Hogue, Christie; Mintzer, Michael J

2015-01-01

Medical students (MS) may develop ageist attitudes early in their training that may predict their future avoidance of caring for the elderly. This study sought to determine MS' patterns of explicit and implicit anti-aging bias, intent to practice with older people and using the quad model, the role of gender, race, and motivation-based differences. One hundred and three MS completed an online survey that included explicit and implicit measures. Explicit measures revealed a moderately positive perception of older people. Female medical students and those high in internal motivation showed lower anti-aging bias, and both were more likely to intend to practice with older people. Although the implicit measure revealed more negativity toward the elderly than the explicit measures, there were no group differences. However, using the quad model the authors identified gender, race, and motivation-based differences in controlled and automatic processes involved in anti-aging bias.

Stereotype Threat and Women's Performance in Physics

NASA Astrophysics Data System (ADS)

Marchand, Gwen C.; Taasoobshirazi, Gita

2013-12-01

Stereotype threat (ST), which involves confirming a negative stereotype about one's group, is a factor thought to contribute to the gender gap in science achievement and participation. This study involved a quasi-experiment in which 312 US high school physics students were randomly assigned, via their classroom cluster, to one of three ST conditions. The conditions included an explicit ST condition, an implicit ST condition, and a nullified condition. Results indicated that males in all three conditions performed similarly on a set of physics problems. Females in the nullified condition outperformed females in the explicit ST condition and females in the implicit and explicit conditions performed similarly. Males performed better than females in the implicit and explicit ST conditions, but male and female performance on the physics problems was not significantly different in the nullified condition. The implications of these findings for physics instruction and future research on gender differences in physics and ST in science are discussed.

Federal Workforce Quality: Measurement and Improvement

DTIC Science & Technology

1992-08-01

explicit standards of production and service quality . Assessment Tools 4 OPM should institutionalize its data collection program of longitudinal research...include data about quirements, should set explicit standards of various aspects of the model. That is, the production and service quality . effort...are the immediate consumers service quality are possible. of the products and services delivered, and still others in the larger society who have no

DoD Product Line Practice Workshop Report

DTIC Science & Technology

1998-05-01

capability. The essential enterprise management practices include ensuring sound business goals providing an appropriate funding model performing...business. This way requires vision and explicit support at the organizational level. There must be an explicit funding model to support the development...the same group seems to work best in smaller organizations. A funding model for core asset development also needs to be developed because the core

Quarantine for pandemic influenza control at the borders of small island nations.

PubMed

Nishiura, Hiroshi; Wilson, Nick; Baker, Michael G

2009-03-11

Although border quarantine is included in many influenza pandemic plans, detailed guidelines have yet to be formulated, including considerations for the optimal quarantine length. Motivated by the situation of small island nations, which will probably experience the introduction of pandemic influenza via just one airport, we examined the potential effectiveness of quarantine as a border control measure. Analysing the detailed epidemiologic characteristics of influenza, the effectiveness of quarantine at the borders of islands was modelled as the relative reduction of the risk of releasing infectious individuals into the community, explicitly accounting for the presence of asymptomatic infected individuals. The potential benefit of adding the use of rapid diagnostic testing to the quarantine process was also considered. We predict that 95% and 99% effectiveness in preventing the release of infectious individuals into the community could be achieved with quarantine periods of longer than 4.7 and 8.6 days, respectively. If rapid diagnostic testing is combined with quarantine, the lengths of quarantine to achieve 95% and 99% effectiveness could be shortened to 2.6 and 5.7 days, respectively. Sensitivity analysis revealed that quarantine alone for 8.7 days or quarantine for 5.7 days combined with using rapid diagnostic testing could prevent secondary transmissions caused by the released infectious individuals for a plausible range of prevalence at the source country (up to 10%) and for a modest number of incoming travellers (up to 8000 individuals). Quarantine at the borders of island nations could contribute substantially to preventing the arrival of pandemic influenza (or at least delaying the arrival date). For small island nations we recommend consideration of quarantine alone for 9 days or quarantine for 6 days combined with using rapid diagnostic testing (if available).

Quarantine for pandemic influenza control at the borders of small island nations

PubMed Central

2009-01-01

Background Although border quarantine is included in many influenza pandemic plans, detailed guidelines have yet to be formulated, including considerations for the optimal quarantine length. Motivated by the situation of small island nations, which will probably experience the introduction of pandemic influenza via just one airport, we examined the potential effectiveness of quarantine as a border control measure. Methods Analysing the detailed epidemiologic characteristics of influenza, the effectiveness of quarantine at the borders of islands was modelled as the relative reduction of the risk of releasing infectious individuals into the community, explicitly accounting for the presence of asymptomatic infected individuals. The potential benefit of adding the use of rapid diagnostic testing to the quarantine process was also considered. Results We predict that 95% and 99% effectiveness in preventing the release of infectious individuals into the community could be achieved with quarantine periods of longer than 4.7 and 8.6 days, respectively. If rapid diagnostic testing is combined with quarantine, the lengths of quarantine to achieve 95% and 99% effectiveness could be shortened to 2.6 and 5.7 days, respectively. Sensitivity analysis revealed that quarantine alone for 8.7 days or quarantine for 5.7 days combined with using rapid diagnostic testing could prevent secondary transmissions caused by the released infectious individuals for a plausible range of prevalence at the source country (up to 10%) and for a modest number of incoming travellers (up to 8000 individuals). Conclusion Quarantine at the borders of island nations could contribute substantially to preventing the arrival of pandemic influenza (or at least delaying the arrival date). For small island nations we recommend consideration of quarantine alone for 9 days or quarantine for 6 days combined with using rapid diagnostic testing (if available). PMID:19284571

[Internet Addiction, Suicidality and Non-Suicidal Self-Harming Behavior - A Systematic Review].

PubMed

Steinbüchel, Toni Andreas; Herpertz, Stephan; Külpmann, Ina; Kehyayan, Aram; Dieris-Hirche, Jan; Te Wildt, Bert Theodor

2017-11-23

Background Internet addiction (IA) is associated with a high rate of co-morbid mental disorders, especially depression, anxiety disorders, ADHD and personality disorders and a considerable level of psychological strain. In terms of risk assessment, the present work investigates the current research literature on suicidal behavior and non-suicidal self-injurious behavior (NSSI). Methods We performed a systematic literature search in 14 databases on title and abstract level for the most common keywords for IA, NSSI and suicidality. After deduction of multiple items, 2334 articles remained. They were filtered per inclusion and exclusion criteria. We identified studies that examined the relationship between IA, NSSI and suicidality, which were assessed by validated psychometric instruments. This allowed a total of 15 studies to be included. Results The relationship between IA and suicidality was examined in 10 studies, four studies examined the relationship of IA, suicidality, and NSSI, and one study exclusively focused on IA and NSSHB. All studies showed higher prevalence for NSSI and respectively suicidality of the subjects with an IA compared to subjects without IA, with point prevalence varying considerably between 1.6-18.7%. Discussion The results of the included publications suggest that Internet dependency is associated with an increased rate of non-suicidal self-harming behavior and increased suicidality, with suicidal ideation being more closely related to IA than suicidal actions. In order to develop a better understanding of causal relationships between IA, NSSI and suicidality, further longitudinal studies are required. Conclusion  Against the background of the presented studies NSSHB and suicidality need to be explicitly addressed within the assessment and treatment of IA patients. © Georg Thieme Verlag KG Stuttgart · New York.

Factors Influencing Learning Environments in an Integrated Experiential Program

NASA Astrophysics Data System (ADS)

Koci, Peter

The research conducted for this dissertation examined the learning environment of a specific high school program that delivered the explicit curriculum through an integrated experiential manner, which utilized field and outdoor experiences. The program ran over one semester (five months) and it integrated the grade 10 British Columbian curriculum in five subjects. A mixed methods approach was employed to identify the students' perceptions and provide richer descriptions of their experiences related to their unique learning environment. Quantitative instruments were used to assess changes in students' perspectives of their learning environment, as well as other supporting factors including students' mindfulness, and behaviours towards the environment. Qualitative data collection included observations, open-ended questions, and impromptu interviews with the teacher. The qualitative data describe the factors and processes that influenced the learning environment and give a richer, deeper interpretation which complements the quantitative findings. The research results showed positive scores on all the quantitative measures conducted, and the qualitative data provided further insight into descriptions of learning environment constructs that the students perceived as most important. A major finding was that the group cohesion measure was perceived by students as the most important attribute of their preferred learning environment. A flow chart was developed to help the researcher conceptualize how the learning environment, learning process, and outcomes relate to one another in the studied program. This research attempts to explain through the consideration of this case study: how learning environments can influence behavioural change and how an interconnectedness among several factors in the learning process is influenced by the type of learning environment facilitated. Considerably more research is needed in this area to understand fully the complexity learning environments and how they influence learning and behaviour. Keywords: learning environments; integrated experiential programs; environmental education.

Nye County Nevada Perspectives on the State of the Yucca Mountain Project - 12388

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

Lacy, Darrell; Voegele, Michael; Jaszczak, Casmier

2012-07-01

Responding to the Department of Energy decision to try to withdraw the Yucca Mountain license application and the Administration actions to close down the Yucca Mountain project, Nye County undertook a number of activities to articulate its support for continuing the Yucca Mountain project. The activities included responding to inquiries from federal agencies, including investigations undertaken by the Government Accountability Office addressing other potential uses for the Yucca Mountain site, responding to a Draft Environmental Impact Statement on the possible use of Yucca Mountain for disposal of Greater than Class C wastes, testifying in hearings, and interacting with the President'smore » Blue Ribbon Commission on America's Nuclear Future. The paper summarizes Nye County's position on the Yucca Mountain repository, Nye County's perspectives on the various activities that were developed and considered by the Government Accountability Office, Nye County's concerns with the use of the Nevada National Security Site for Disposal of Greater than Class C Low-Level Radioactive Wastes, testimony of Nye County officials expressing local community support for the Yucca Mountain project, and Nye County's perspectives on recommendations provided by the Blue Ribbon Commission to move the nation's high-level radioactive waste disposal programs forward without consideration of the role Yucca Mountain could have served in those recommendations. Nye County believes that every effort should be made to, at a minimum, fund the Nuclear Regulatory Commission to complete the license application review. Then, if Congress does decide to change the Nuclear Waste Policy Act, there will be valuable information available to support new policy development. This administration contends that Congressional language associated with the FY2010 and FY2011 appropriations and authorization process is sufficient evidence of its intent to terminate the Yucca Mountain repository program. The appropriation process needs to be explicit that, absent explicit language to the contrary, the Nuclear Waste Policy Act stands. It also should include language that requires the Department of Energy to preserve all necessary records until the Nuclear Waste Policy Act is amended or rescinded by specific Congressional action. (authors)« less

Consideration of social values in the establishment of accountable care organizations in the USA.

PubMed

Keren, Ron; Littlejohns, Peter

2012-01-01

The purpose of this paper is to introduce the new US health organizations called accountable care organizations (ACOs) which are expected to improve the quality and reduce the cost of healthcare for Medicare enrolees. It assesses the importance of ACOs, defining and articulating the values that will underpin their strategic and clinical decision making. This paper uses a social values framework developed by Clark and Weale to consider the values relevant to ACOs. It is likely that social values could be made more explicit in a US setting than they have ever been before, via the new ACOs. Social values could start to form part of a local health economy's marketing strategy. ACOs are very new. This paper identifies that they will need to be very explicit about the values relevant to them. The development of ACOs and the articulation of social values therein may even form the basis of a meaningful dialogue on the importance of assessing value for money or cost-effectiveness in the wider US health policy environment.

Principles and Benefits of Explicitly Designed Medical Device Safety Architecture.

PubMed

Larson, Brian R; Jones, Paul; Zhang, Yi; Hatcliff, John

The complexity of medical devices and the processes by which they are developed pose considerable challenges to producing safe designs and regulatory submissions that are amenable to effective reviews. Designing an appropriate and clearly documented architecture can be an important step in addressing this complexity. Best practices in medical device design embrace the notion of a safety architecture organized around distinct operation and safety requirements. By explicitly separating many safety-related monitoring and mitigation functions from operational functionality, the aspects of a device most critical to safety can be localized into a smaller and simpler safety subsystem, thereby enabling easier verification and more effective reviews of claims that causes of hazardous situations are detected and handled properly. This article defines medical device safety architecture, describes its purpose and philosophy, and provides an example. Although many of the presented concepts may be familiar to those with experience in realization of safety-critical systems, this article aims to distill the essence of the approach and provide practical guidance that can potentially improve the quality of device designs and regulatory submissions.

Explicit formulae for Yang-Mills-Einstein amplitudes from the double copy

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

Chiodaroli, Marco; Günaydin, Murat; Johansson, Henrik

Using the double-copy construction of Yang-Mills-Einstein theories formulated in our earlier work, we obtain compact presentations for single-trace Yang-Mills-Einstein tree amplitudes with up to five external gravitons and an arbitrary number of gluons. These are written as linear combinations of color-ordered Yang-Mills trees, where the coefficients are given by color/kinematics-satisfying numerators in a Yang-Mills + φ 3 theory. The construction outlined in this paper holds in general dimension and extends straightforwardly to supergravity theories. For one, two, and three external gravitons, our expressions give identical or simpler presentations of amplitudes already constructed through string-theory considerations or the scattering equations formalism.more » Our results are based on color/kinematics duality and gauge invariance, and strongly hint at a recursive structure underlying the single-trace amplitudes with an arbitrary number of gravitons. We also present explicit expressions for all-loop single-graviton Einstein-Yang-Mills amplitudes in terms of Yang-Mills amplitudes and, through gauge invariance, derive new all-loop amplitude relations for Yang-Mills theory.« less

Mothers, Intrinsic Math Motivation, Arithmetic Skills, and Math Anxiety in Elementary School

PubMed Central

Daches Cohen, Lital; Rubinsten, Orly

2017-01-01

Math anxiety is influenced by environmental, cognitive, and personal factors. Yet, the concurrent relationships between these factors have not been examined. To this end, the current study investigated how the math anxiety of 30 sixth graders is affected by: (a) mother’s math anxiety and maternal behaviors (environmental factors); (b) children’s arithmetic skills (cognitive factors); and (c) intrinsic math motivation (personal factor). A rigorous assessment of children’s math anxiety was made by using both explicit and implicit measures. The results indicated that accessible self-representations of math anxiety, as reflected by the explicit self-report questionnaire, were strongly affected by arithmetic skills. However, unconscious cognitive constructs of math anxiety, as reflected by the numerical dot-probe task, were strongly affected by environmental factors, such as maternal behaviors and mothers’ attitudes toward math. Furthermore, the present study provided preliminary evidence of intergenerational transmission of math anxiety. The conclusions are that in order to better understand the etiology of math anxiety, multiple facets of parenting and children’s skills should be taken into consideration. Implications for researchers, parents, and educators are discussed. PMID:29180973

Explicit formulae for Yang-Mills-Einstein amplitudes from the double copy

DOE PAGES

Chiodaroli, Marco; Günaydin, Murat; Johansson, Henrik; ...

2017-07-03

Using the double-copy construction of Yang-Mills-Einstein theories formulated in our earlier work, we obtain compact presentations for single-trace Yang-Mills-Einstein tree amplitudes with up to five external gravitons and an arbitrary number of gluons. These are written as linear combinations of color-ordered Yang-Mills trees, where the coefficients are given by color/kinematics-satisfying numerators in a Yang-Mills + φ 3 theory. The construction outlined in this paper holds in general dimension and extends straightforwardly to supergravity theories. For one, two, and three external gravitons, our expressions give identical or simpler presentations of amplitudes already constructed through string-theory considerations or the scattering equations formalism.more » Our results are based on color/kinematics duality and gauge invariance, and strongly hint at a recursive structure underlying the single-trace amplitudes with an arbitrary number of gravitons. We also present explicit expressions for all-loop single-graviton Einstein-Yang-Mills amplitudes in terms of Yang-Mills amplitudes and, through gauge invariance, derive new all-loop amplitude relations for Yang-Mills theory.« less

Neutron coincidence measurements when nuclear parameters vary during the multiplication process

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

Lu, Ming-Shih; Teichmann, T.

1995-07-01

In a recent paper, a physical/mathematical model was developed for neutron coincidence counting, taking explicit account of neutron absorption and leakage, and using dual probability generating function to derive explicit formulae for the single and multiple count-rates in terms of the physical parameters of the system. The results of this modeling proved very successful in a number of cases in which the system parameters (neutron reaction cross-sections, detection probabilities, etc.) remained the same at the various stages of the process (i.e. from collision to collision). However, there are practical circumstances in which such system parameters change from collision to collision,more » and it is necessary to accommodate these, too, in a general theory, applicable to such situations. For instance, in the case of the neutron coincidence collar (NCC), the parameters for the initial, spontaneous fission neutrons, are not the same as those for the succeeding induced fission neutrons, and similar situations can be envisaged for certain other experimental configurations. This present document shows how the previous considerations can be elaborated to embrace these more general requirements.« less

Mothers, Intrinsic Math Motivation, Arithmetic Skills, and Math Anxiety in Elementary School.

PubMed

Daches Cohen, Lital; Rubinsten, Orly

2017-01-01

Math anxiety is influenced by environmental, cognitive, and personal factors. Yet, the concurrent relationships between these factors have not been examined. To this end, the current study investigated how the math anxiety of 30 sixth graders is affected by: (a) mother's math anxiety and maternal behaviors (environmental factors); (b) children's arithmetic skills (cognitive factors); and (c) intrinsic math motivation (personal factor). A rigorous assessment of children's math anxiety was made by using both explicit and implicit measures. The results indicated that accessible self-representations of math anxiety, as reflected by the explicit self-report questionnaire, were strongly affected by arithmetic skills. However, unconscious cognitive constructs of math anxiety, as reflected by the numerical dot-probe task, were strongly affected by environmental factors, such as maternal behaviors and mothers' attitudes toward math. Furthermore, the present study provided preliminary evidence of intergenerational transmission of math anxiety. The conclusions are that in order to better understand the etiology of math anxiety, multiple facets of parenting and children's skills should be taken into consideration. Implications for researchers, parents, and educators are discussed.

Making the Implicit Explicit: Towards an Assurance Case for DO-178C

NASA Technical Reports Server (NTRS)

Holloway, C. Michael

2013-01-01

For about two decades, compliance with Software Considerations in Airborne Systems and Equipment Certification (DO-178B) has been the primary means for receiving regulatory approval for using software on commercial airplanes. A new edition of the standard, DO-178C, was published in December 2011, and regulatory bodies have started the process towards recognizing this edition. The stated purpose of DO-178C remains unchanged from its predecessor: providing guidance “for the production of software for airborne systems and equipment that performs its intended function with a level of confidence in safety that complies with airworthiness requirements.” Within the text of the guidance, little or no rationale is given for how a particular objective or collection of objectives contributes to achieving this purpose. Thus the assurance case for the document is implicit. This paper discusses a current effort to make the implicit explicit. In particular, the paper describes the current status of the research seeking to identify the specific arguments contained in, or implied by, the DO-178C guidance that implicitly justify the assumption that the document meets its stated purpose.

The Impact of Aerosol Microphysical Representation in Models on the Direct Radiative Effect

NASA Astrophysics Data System (ADS)

Ridley, D. A.; Heald, C. L.

2017-12-01

Aerosol impacts the radiative balance of the atmosphere both directly and indirectly. There is considerable uncertainty remaining in the aerosol direct radiative effect (DRE), hampering understanding of the present magnitude of anthropogenic aerosol forcing and how future changes in aerosol loading will influence climate. Computationally expensive explicit aerosol microphysics are usually reserved for modelling of the aerosol indirect radiative effects that depend upon aerosol particle number. However, the direct radiative effects of aerosol are also strongly dependent upon the aerosol size distribution, especially particles between 0.2µm - 2µm diameter. In this work, we use a consistent model framework and consistent emissions to explore the impact of prescribed size distributions (bulk scheme) relative to explicit microphysics (sectional scheme) on the aerosol radiative properties. We consider the difference in aerosol burden, water uptake, and extinction efficiency resulting from the two representations, highlighting when and where the bulk and sectional schemes diverge significantly in their estimates of the DRE. Finally, we evaluate the modelled size distributions using in-situ measurements over a range of regimes to provide constraints on both the accumulation and coarse aerosol sizes.

What values in design? The challenge of incorporating moral values into design.

PubMed

Manders-Huits, Noëmi

2011-06-01

Recently, there is increased attention to the integration of moral values into the conception, design, and development of emerging IT. The most reviewed approach for this purpose in ethics and technology so far is Value-Sensitive Design (VSD). This article considers VSD as the prime candidate for implementing normative considerations into design. Its methodology is considered from a conceptual, analytical, normative perspective. The focus here is on the suitability of VSD for integrating moral values into the design of technologies in a way that joins in with an analytical perspective on ethics of technology. Despite its promising character, it turns out that VSD falls short in several respects: (1) VSD does not have a clear methodology for identifying stakeholders, (2) the integration of empirical methods with conceptual research within the methodology of VSD is obscure, (3) VSD runs the risk of committing the naturalistic fallacy when using empirical knowledge for implementing values in design, (4) the concept of values, as well as their realization, is left undetermined and (5) VSD lacks a complimentary or explicit ethical theory for dealing with value trade-offs. For the normative evaluation of a technology, I claim that an explicit and justified ethical starting point or principle is required. Moreover, explicit attention should be given to the value aims and assumptions of a particular design. The criteria of adequacy for such an approach or methodology follow from the evaluation of VSD as the prime candidate for implementing moral values in design.

Challenging some assumptions about empathy.

PubMed

Gallagher, Peter; Moriarty, Helen; Huthwaite, Mark; Lim, Bee

2017-12-01

In New Zealand little nursing or medical curricula time, if any, is specifically devoted to the enhancement of empathy. If being empathic is important in the context of patient care, it is a quality that is already present in students or is learned by students during their practicum in the company of experienced clinicians. This study aimed to compare self-reported empathy ratings between different groups of medical students and one cohort of nursing students who were either exposed or not exposed to explicit empathy training or learning in clinical settings in the presence of patients. The Jefferson Scale of Physician Empathy (JSPE) was completed before and after groups of medical and nursing students had been exposed to various extended periods of practicum. Some medical student cohorts undertook brief empathy training, whereas others had no exposure. The nursing student cohort had no formal, explicit empathy training. Irrespective of profession, length of practicum or exposure to specific empathy training, there were no significant differences in the self-reported JSPE scores across the seven different cohorts of students. Empathy is a quality that is already present in students or is learned by students during their practicum DISCUSSION: If empathy is caught rather than taught, then brief efforts to enhance empathy may be futile. To optimise the inherent empathic qualities of aspirant health professionals, explicit consideration should be given to how empathy is influenced by the practicum experience. © 2017 John Wiley & Sons Ltd and The Association for the Study of Medical Education.

A Critical Review of Methods to Evaluate the Impact of FDA Regulatory Actions

PubMed Central

Briesacher, Becky A.; Soumerai, Stephen B.; Zhang, Fang; Toh, Sengwee; Andrade, Susan E.; Wagner, Joann L.; Shoaibi, Azadeh; Gurwitz, Jerry H.

2013-01-01

Purpose To conduct a synthesis of the literature on methods to evaluate the impacts of FDA regulatory actions, and identify best practices for future evaluations. Methods We searched MEDLINE for manuscripts published between January 1948 and August 2011 that included terms related to FDA, regulatory actions, and empirical evaluation; the review additionally included FDA-identified literature. We used a modified Delphi method to identify preferred methodologies. We included studies with explicit methods to address threats to validity, and identified designs and analytic methods with strong internal validity that have been applied to other policy evaluations. Results We included 18 studies out of 243 abstracts and papers screened. Overall, analytic rigor in prior evaluations of FDA regulatory actions varied considerably; less than a quarter of studies (22%) included control groups. Only 56% assessed changes in the use of substitute products/services, and 11% examined patient health outcomes. Among studies meeting minimal criteria of rigor, 50% found no impact or weak/modest impacts of FDA actions and 33% detected unintended consequences. Among those studies finding significant intended effects of FDA actions, all cited the importance of intensive communication efforts. There are preferred methods with strong internal validity that have yet to be applied to evaluations of FDA regulatory actions. Conclusions Rigorous evaluations of the impact of FDA regulatory actions have been limited and infrequent. Several methods with strong internal validity are available to improve trustworthiness of future evaluations of FDA policies. PMID:23847020

Finite Element Modeling of Coupled Flexible Multibody Dynamics and Liquid Sloshing

DTIC Science & Technology

2006-09-01

tanks is presented. The semi-discrete combined solid and fluid equations of motions are integrated using a time- accurate parallel explicit solver...Incompressible fluid flow in a moving/deforming container including accurate modeling of the free-surface, turbulence, and viscous effects ...paper, a single computational code which uses a time- accurate explicit solution procedure is used to solve both the solid and fluid equations of

The explicit mentioning of reporting guidelines in urogynecology journals in 2013: A bibliometric study.

PubMed

Koch, Marianne; Riss, Paul; Umek, Wolfgang; Hanzal, Engelbert

2016-03-01

Poor reporting of research may limit critical appraisal and reproducibility, whereas adherence to reporting guidelines (RG) can guarantee completeness and transparency. We aimed to determine the explicit citing of RGs (CONSORT, PRISMA, STROBE) in urogynecology articles in 2013, the requirements of relevant journals and a potential difference between urogynecology and general gynecology journals. All urogynecologic articles published between January and December 2013 in the journals NAU, IUJ, FPMRS, GREEN, AJOG, and BJOG were included. Issues were searched for systematic reviews, RCTs, cohort studies, case-control studies and cross-sectional studies. Each electronic article was searched for the term PRISMA, CONSORT, or STROBE according to the study design. Instructions to Authors of the six journals were screened for requirement of using RGs. We included 296 articles (243 observational studies, 40 RCTs, and 13 systematic reviews). The use of PRISMA guidelines was explicitly declared in 54% of systematic reviews, CONSORT guidelines were referenced in 25% of RCTs and STROBE in 1.2% of observational studies. The use of CONSORT is required by all journals except FPMRS. PRISMA and STROBE are only compulsory in the journals GREEN, AJOG, and BJOG. The overall rate of explicit mentioning of RGs comparing urogynecology and general gynecology journals was 6.7% versus 7.1%, respectively. The explicit mentioning of RGs was on a relatively low level. A slightly higher adherence was recognized among general gynecology journals compared to urogynecology journals. Stronger efforts should be taken to further promote the use of RGs in urogynecology. © 2015 Wiley Periodicals, Inc.

International trade versus public health during the FCTC negotiations, 1999-2003

PubMed Central

Mamudu, Hadii M; Hammond, Ross; Glantz, Stanton A

2011-01-01

Objective To examine why the Framework Convention on Tobacco Control did not include an explicit trade provision and delineate the central arguments in the debate over trade provision during the negotiations. Methods Triangulate interviews with participants in the FCTC negotiations, the FCTC negotiations documents, and tobacco industry documents. Results An explicit FCTC trade provision on relation between international trade and public health became a contentious issue during the negotiations. As a result, two conflicting positions, health-over-trade and opposition to health-over-trade emerged. Opposition to explicit trade language giving health priority was by both tobacco industry and countries that generally supported strong FCTC provisions because of concerns over ‘disguised protectionism’ and setting a precedent whereby governments could forfeit their obligations under pre-existing treaties. Owing to lack of consensus among political actors involved in the negotiations, a compromise position eliminating any mention of trade emerged, which was predicated on belief among some in the public health community that public health would prevail in future trade versus health conflicts. Conclusion The absence of an explicit FCTC trade provision was due to a political compromise rather than the impact of international trade agreements and decisions on public health and lack of consensus among health advocates. This failure to include an explicit trade provision in the FCTC suggests that the public health community should become more involved in trade and health issues at all levels of governance and press the FCTC Conference of the Parties for clarification of this critical issue. PMID:20943828

Understanding the vertical equity judgements underpinning health inequality measures.

PubMed

Allanson, Paul; Petrie, Dennis

2014-11-01

The choice of income-related health inequality measures in comparative studies is often determined by custom and analytical concerns, without much explicit consideration of the vertical equity judgements underlying alternative measures. This note employs an inequality map to illustrate how these judgements determine the ranking of populations by health inequality. In particular, it is shown that relative indices of inequality in health attainments and shortfalls embody distinct vertical equity judgments, where each may represent ethically defensible positions in specific contexts. Further research is needed to explore people's preferences over distributions of income and health. Copyright © 2013 John Wiley & Sons, Ltd.

New more accurate calculations of the ground state potential energy surface of H(3) (+).

PubMed

Pavanello, Michele; Tung, Wei-Cheng; Leonarski, Filip; Adamowicz, Ludwik

2009-02-21

Explicitly correlated Gaussian functions with floating centers have been employed to recalculate the ground state potential energy surface (PES) of the H(3) (+) ion with much higher accuracy than it was done before. The nonlinear parameters of the Gaussians (i.e., the exponents and the centers) have been variationally optimized with a procedure employing the analytical gradient of the energy with respect to these parameters. The basis sets for calculating new PES points were guessed from the points already calculated. This allowed us to considerably speed up the calculations and achieve very high accuracy of the results.

The any particle molecular orbital grid-based Hartree-Fock (APMO-GBHF) approach

NASA Astrophysics Data System (ADS)

Posada, Edwin; Moncada, Félix; Reyes, Andrés

2018-02-01

The any particle molecular orbital grid-based Hartree-Fock approach (APMO-GBHF) is proposed as an initial step to perform multi-component post-Hartree-Fock, explicitly correlated, and density functional theory methods without basis set errors. The method has been applied to a number of electronic and multi-species molecular systems. Results of these calculations show that the APMO-GBHF total energies are comparable with those obtained at the APMO-HF complete basis set limit. In addition, results reveal a considerable improvement in the description of the nuclear cusps of electronic and non-electronic densities.

Design and analysis of aerospace structures at elevated temperatures. [aircraft, missiles, and space platforms

NASA Technical Reports Server (NTRS)

Chang, C. I.

1989-01-01

An account is given of approaches that have emerged as useful in the incorporation of thermal loading considerations into advanced composite materials-based aerospace structural design practices. Sources of structural heating encompass not only propulsion system heat and aerodynamic surface heating at supersonic speeds, but the growing possibility of intense thermal fluxes from directed-energy weapons. The composite materials in question range from intrinsically nonheat-resistant polymer matrix systems to metal-matrix composites, and increasingly to such ceramic-matrix composites as carbon/carbon, which are explicitly intended for elevated temperature operation.

Copyright Holder Protection Act. Hearing before the Subcommittee on Patents, Copyrights and Trademarks of the Committee on the Judiciary. United States Senate, Ninety-Ninth Congress, First Session on S. 1384. A Bill to Amend the Copyright Act of 1976 to Clarify the Operation of the Derivative Works Exception (November 20, 1985).

ERIC Educational Resources Information Center

Congress of the U.S., Washington, DC. Senate Committee on the Judiciary.

This hearing addressed Senate Bill 1384, which deals with the copyright issue and seeks to alter the 5-to-4 decision of the Supreme Court of the United States in the Mills Music case. The question under consideration is whether the law should be made explicit to the effect that the class of intended beneficiaries of all royalties under the…

Automated detection of slum area change in Hyderabad, India using multitemporal satellite imagery

NASA Astrophysics Data System (ADS)

Kit, Oleksandr; Lüdeke, Matthias

2013-09-01

This paper presents an approach to automated identification of slum area change patterns in Hyderabad, India, using multi-year and multi-sensor very high resolution satellite imagery. It relies upon a lacunarity-based slum detection algorithm, combined with Canny- and LSD-based imagery pre-processing routines. This method outputs plausible and spatially explicit slum locations for the whole urban agglomeration of Hyderabad in years 2003 and 2010. The results indicate a considerable growth of area occupied by slums between these years and allow identification of trends in slum development in this urban agglomeration.

Axisymmetric buckling of the circular graphene sheets with the nonlocal continuum plate model

NASA Astrophysics Data System (ADS)

Farajpour, A.; Mohammadi, M.; Shahidi, A. R.; Mahzoon, M.

2011-08-01

In this article, the buckling behavior of nanoscale circular plates under uniform radial compression is studied. Small-scale effect is taken into consideration. Using nonlocal elasticity theory the governing equations are derived for the circular single-layered graphene sheets (SLGS). Explicit expressions for the buckling loads are obtained for clamped and simply supported boundary conditions. It is shown that nonlocal effects play an important role in the buckling of circular nanoplates. The effects of the small scale on the buckling loads considering various parameters such as the radius of the plate and mode numbers are investigated.

Model-based frequency response characterization of a digital-image analysis system for epifluorescence microscopy

NASA Technical Reports Server (NTRS)

Hazra, Rajeeb; Viles, Charles L.; Park, Stephen K.; Reichenbach, Stephen E.; Sieracki, Michael E.

1992-01-01

Consideration is given to a model-based method for estimating the spatial frequency response of a digital-imaging system (e.g., a CCD camera) that is modeled as a linear, shift-invariant image acquisition subsystem that is cascaded with a linear, shift-variant sampling subsystem. The method characterizes the 2D frequency response of the image acquisition subsystem to beyond the Nyquist frequency by accounting explicitly for insufficient sampling and the sample-scene phase. Results for simulated systems and a real CCD-based epifluorescence microscopy system are presented to demonstrate the accuracy of the method.

Understanding and preventing military suicide.

PubMed

Bryan, Craig J; Jennings, Keith W; Jobes, David A; Bradley, John C

2012-01-01

The continual rise in the U.S. military's suicide rate since 2004 is one of the most vexing issues currently facing military leaders, mental health professionals, and suicide experts. Despite considerable efforts to address this problem, however, suicide rates have not decreased. The authors consider possible reasons for this frustrating reality, and question common assumptions and approaches to military suicide prevention. They further argue that suicide prevention efforts that more explicitly embrace the military culture and implement evidence-based strategies across the full spectrum of prevention and treatment could improve success. Several recommendations for augmenting current efforts to prevent military suicide are proposed.

How to Connect Cardiac Excitation to the Atomic Interactions of Ion Channels.

PubMed

Silva, Jonathan R

2018-01-23

Many have worked to create cardiac action potential models that explicitly represent atomic-level details of ion channel structure. Such models have the potential to define new therapeutic directions and to show how nanoscale perturbations to channel function predispose patients to deadly cardiac arrhythmia. However, there have been significant experimental and theoretical barriers that have limited model usefulness. Recently, many of these barriers have come down, suggesting that considerable progress toward creating these long-sought models may be possible in the near term. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Learning from New York City : a case study of public health policy practice in the Bloomberg administration.

PubMed

Isett, Kimberley Roussin; Laugesen, Miriam J; Cloud, David H

2015-01-01

To ascertain any lessons learned about how public health reforms undertaken in New York City during the Bloomberg Administration were shepherded through the public policy and administration gauntlet. The question is, how feasible is this approach and would it work outside of New York City? Using a theoretically grounded case study approach, 3 initiatives were examined that were proposed and/or implemented during a 10-year period of the Mayoralty of Michael Bloomberg (2002-2011): transfats restrictions, clean bus transportation policies, and a sugar-sweetened beverages tax (as a counterfactual). The investigation began by performing a comprehensive public documents search and was followed with interviews of 27 individuals involved in the selected policy initiatives. Interviews were coded in Nvivo using an iterative, grounded methodology. Using a theoretical lens, the case study illustrates that the multifaceted role of leadership was not confined to the executives in the City or the Agency. Instead, leadership extended to other administrative officials within the agency and the Board of Health. Second, New York City used reorganization and coordinative mechanisms strategically to ensure achievement of their goals. This included creation of new departments/bureaus and coordinating structures across the City. Evidence of the explicit use of incentives, as initially anticipated from the theoretical framework, was not found. While some aspects of this case study are unique to the context of New York City, 2 approaches used in New York City are feasible for other jurisdictions: harnessing the full scope and breadth of authority of the agency and its associated boards and commissions, and remobilizing existing workforce to explicitly focus on and coordinate targeted policies for issues of concern. Questions for further consideration are posed at the conclusion of the article.

What does quality of life refer to in bipolar disorders research? A systematic review of the construct's definition, usage and measurement.

PubMed

Morton, Emma; Michalak, Erin E; Murray, Greg

2017-04-01

Quality of life (QoL) is increasingly investigated in bipolar disorders (BD) research, yet little attention has been paid to its optimal definition and measurement. This is a significant limitation, as the broader QoL literature recognises a number of divergent meanings and measurement tensions. The aim here was to advance understanding of QoL in BD by clarifying use of the construct in the existing literature and considering measurement implications. Thematic analysis techniques were used to interrogate articles identified via systematic search for (a) explicit discussion of QoL definitional/measurement issues, and (b) usage of the term QoL. A total of 275 articles were included in the analysis. A range of definitional and methodological issues confounding the study of QoL in BD were identified. While explicit definition of QoL proved rare, thematic analysis of usage of the construct revealed the concepts of functioning, health, subjective experience and wellbeing were thought to be relevant to QoL in BD. The review does not engage in top-down theory development. Our analysis was grounded in the empirical literature to support future theoretical work relevant to existing usage of QoL in BD. There was no evidence of a consensus definition of QoL in BD. A plurality of QoL definitions is not necessarily a flaw in the literature, but points to empirical and conceptual issues demanding attention. Awareness of the diversity of constructs associated with QoL will enable clinicians to better select treatments on the basis of specific QoL outcomes. A research agenda and provisional considerations for empirical research are outlined based on the present analyses. Copyright © 2017 Elsevier B.V. All rights reserved.

An Accurate Fire-Spread Algorithm in the Weather Research and Forecasting Model Using the Level-Set Method

NASA Astrophysics Data System (ADS)

Muñoz-Esparza, Domingo; Kosović, Branko; Jiménez, Pedro A.; Coen, Janice L.

2018-04-01

The level-set method is typically used to track and propagate the fire perimeter in wildland fire models. Herein, a high-order level-set method using fifth-order WENO scheme for the discretization of spatial derivatives and third-order explicit Runge-Kutta temporal integration is implemented within the Weather Research and Forecasting model wildland fire physics package, WRF-Fire. The algorithm includes solution of an additional partial differential equation for level-set reinitialization. The accuracy of the fire-front shape and rate of spread in uncoupled simulations is systematically analyzed. It is demonstrated that the common implementation used by level-set-based wildfire models yields to rate-of-spread errors in the range 10-35% for typical grid sizes (Δ = 12.5-100 m) and considerably underestimates fire area. Moreover, the amplitude of fire-front gradients in the presence of explicitly resolved turbulence features is systematically underestimated. In contrast, the new WRF-Fire algorithm results in rate-of-spread errors that are lower than 1% and that become nearly grid independent. Also, the underestimation of fire area at the sharp transition between the fire front and the lateral flanks is found to be reduced by a factor of ≈7. A hybrid-order level-set method with locally reduced artificial viscosity is proposed, which substantially alleviates the computational cost associated with high-order discretizations while preserving accuracy. Simulations of the Last Chance wildfire demonstrate additional benefits of high-order accurate level-set algorithms when dealing with complex fuel heterogeneities, enabling propagation across narrow fuel gaps and more accurate fire backing over the lee side of no fuel clusters.

Non-muscle invasive bladder cancer: Are epicrises the ‘Bermuda Triangle’ of information transfer?

PubMed Central

May, Matthias; Wick, Anne-Kathrin; Roiner, Michael; Mathew, Marcella; Gilfrich, Christian; Schostak, Martin

2017-01-01

Introduction The aim of the study was to collect information regarding the quality of communication of risk-determining factors or risk profile, and the guideline conformity of recommendations for adjuvant treatment in patients with non-muscle invasive bladder cancer (NMIBC) between clinical and ambulatory urologists. Material and methods At three German urological clinics during the period between 2012-2014, epicrises of 1,033 NMIBC-patients were retrospectively summarised to 505 tumour episodes (tumour resection including any re-resections) and analysed regarding the endpoints 1) risk profile is explicitly named or recorded risk factors are sufficient for the determination of risk profile, and 2) guideline conformity of treatment recommendation. Independent factors influencing the endpoints were determined by means of multivariate logistic regression models. Results The risk profile was explicitly named for 3.6% of tumour episodes; for 68.9% a risk profile could be derived from the information in the epicrises. Treatment recommendations were given for 93.7% of tumour episodes, but only 17.8% were guideline compliant. 42.6% of the recommendations were not reliably effective; 33.1% and 0.2% resulted in under- and overtreatment respectively. Neither endpoint showed gender specific or regional differences, but both were considerably less likely to be achieved in case of recurrence. Conclusions The discrepancy between treatment recommendation (93.7%) and guideline compliance (17.8%) could indicate a lack of familiarity with guidelines. The quality of the epicrises of NMIBC-patients was poor and bore the potential risk of undertreatment. The results of this study are not necessarily applicable to other clinics, but could, however, prompt physicians to re-examine epicrises for the fulfillment of the quality criteria examined here. PMID:29104786

Non-muscle invasive bladder cancer: Are epicrises the 'Bermuda Triangle' of information transfer?

PubMed

Lebentrau, Steffen; May, Matthias; Wick, Anne-Kathrin; Roiner, Michael; Mathew, Marcella; Gilfrich, Christian; Schostak, Martin

2017-01-01

The aim of the study was to collect information regarding the quality of communication of risk-determining factors or risk profile, and the guideline conformity of recommendations for adjuvant treatment in patients with non-muscle invasive bladder cancer (NMIBC) between clinical and ambulatory urologists. At three German urological clinics during the period between 2012-2014, epicrises of 1,033 NMIBC-patients were retrospectively summarised to 505 tumour episodes (tumour resection including any re-resections) and analysed regarding the endpoints 1) risk profile is explicitly named or recorded risk factors are sufficient for the determination of risk profile, and 2) guideline conformity of treatment recommendation. Independent factors influencing the endpoints were determined by means of multivariate logistic regression models. The risk profile was explicitly named for 3.6% of tumour episodes; for 68.9% a risk profile could be derived from the information in the epicrises. Treatment recommendations were given for 93.7% of tumour episodes, but only 17.8% were guideline compliant. 42.6% of the recommendations were not reliably effective; 33.1% and 0.2% resulted in under- and overtreatment respectively. Neither endpoint showed gender specific or regional differences, but both were considerably less likely to be achieved in case of recurrence. The discrepancy between treatment recommendation (93.7%) and guideline compliance (17.8%) could indicate a lack of familiarity with guidelines. The quality of the epicrises of NMIBC-patients was poor and bore the potential risk of undertreatment. The results of this study are not necessarily applicable to other clinics, but could, however, prompt physicians to re-examine epicrises for the fulfillment of the quality criteria examined here.

Charged Substrate and Product Together Contribute Like a Nonreactive Species to the Overall Electrostatic Steering in Diffusion-Reaction Processes.

PubMed

Xu, Jingjie; Xie, Yan; Lu, Benzhuo; Zhang, Linbo

2016-08-25

The Debye-Hückel limiting law is used to study the binding kinetics of substrate-enzyme system as well as to estimate the reaction rate of a electrostatically steered diffusion-controlled reaction process. It is based on a linearized Poisson-Boltzmann model and known for its accurate predictions in dilute solutions. However, the substrate and product particles are in nonequilibrium states and are possibly charged, and their contributions to the total electrostatic field cannot be explicitly studied in the Poisson-Boltzmann model. Hence the influences of substrate and product on reaction rate coefficient were not known. In this work, we consider all the charged species, including the charged substrate, product, and mobile salt ions in a Poisson-Nernst-Planck model, and then compare the results with previous work. The results indicate that both the charged substrate and product can significantly influence the reaction rate coefficient with different behaviors under different setups of computational conditions. It is interesting to find that when substrate and product are both considered, under an overall neutral boundary condition for all the bulk charged species, the computed reaction rate kinetics recovers a similar Debye-Hückel limiting law again. This phenomenon implies that the charged product counteracts the influence of charged substrate on reaction rate coefficient. Our analysis discloses the fact that the total charge concentration of substrate and product, though in a nonequilibrium state individually, obeys an equilibrium Boltzmann distribution, and therefore contributes as a normal charged ion species to ionic strength. This explains why the Debye-Hückel limiting law still works in a considerable range of conditions even though the effects of charged substrate and product particles are not specifically and explicitly considered in the theory.

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

Matsui, H.; Koike, Makoto; Takegawa, Nobuyuki

The new particle formation (NPF)-explicit version of the WRF-chem model, which we developed recently, can calculate the growth and sink of nucleated clusters explicitly with 20 aerosol size bins from 1 nm to 10 μm. In this study, the model is used to understand spatial and temporal variations of the frequency of NPF events and the concentrations of aerosols (condensation nuclei, CN) and cloud condensation nuclei (CCN) within the boundary layer in East Asia in spring 2009. Model simulations show distinct north-south contrast in the frequency and mechanism of NPF in East Asia. NPF mostly occurred over limited periods andmore » regions between 30° and 45°N, such as northeast China, Korea, and Japan, including regions around active volcanoes (Miyakejima and Sakurajima). At these latitudes, NPF was considerably suppressed by high concentrations of preexisting particles under stagnant air conditions associated with high-pressure systems, while nucleation occurred more extensively on most days during the simulation period. Conversely, neither nucleation nor NPF occurred frequently south of 30°N because of lower SO2 emissions and H2SO4 concentrations. The period-averaged NPF frequency was 3 times higher at latitudes of 30° - 45°N than at latitudes of 20° - 30°N. The north-south contrast of NPF frequency is validated by surface measurements in outflow regions in East Asia. The period- and domain-averaged contribution of secondary particles is estimated to be 44% for CN (> 10 nm) and 26% for CCN at a supersaturation of 1.0% in our simulation, though the contribution is highly sensitive to the magnitudes and size distributions of primary aerosol emissions and the coefficients in the nucleation parameterizations.« less

Embedding ecosystem services in coastal planning leads to better outcomes for people and nature

PubMed Central

Arkema, Katie K.; Verutes, Gregory M.; Wood, Spencer A.; Clarke-Samuels, Chantalle; Rosado, Samir; Canto, Maritza; Rosenthal, Amy; Ruckelshaus, Mary; Guannel, Gregory; Toft, Jodie; Faries, Joe; Silver, Jessica M.; Griffin, Robert; Guerry, Anne D.

2015-01-01

Recent calls for ocean planning envision informed management of social and ecological systems to sustain delivery of ecosystem services to people. However, until now, no coastal and marine planning process has applied an ecosystem-services framework to understand how human activities affect the flow of benefits, to create scenarios, and to design a management plan. We developed models that quantify services provided by corals, mangroves, and seagrasses. We used these models within an extensive engagement process to design a national spatial plan for Belize’s coastal zone. Through iteration of modeling and stakeholder engagement, we developed a preferred plan, currently under formal consideration by the Belizean government. Our results suggest that the preferred plan will lead to greater returns from coastal protection and tourism than outcomes from scenarios oriented toward achieving either conservation or development goals. The plan will also reduce impacts to coastal habitat and increase revenues from lobster fishing relative to current management. By accounting for spatial variation in the impacts of coastal and ocean activities on benefits that ecosystems provide to people, our models allowed stakeholders and policymakers to refine zones of human use. The final version of the preferred plan improved expected coastal protection by >25% and more than doubled the revenue from fishing, compared with earlier versions based on stakeholder preferences alone. Including outcomes in terms of ecosystem-service supply and value allowed for explicit consideration of multiple benefits from oceans and coasts that typically are evaluated separately in management decisions. PMID:26082545

Bayesian characterization of uncertainty in species interaction strengths.

PubMed

Wolf, Christopher; Novak, Mark; Gitelman, Alix I

2017-06-01

Considerable effort has been devoted to the estimation of species interaction strengths. This effort has focused primarily on statistical significance testing and obtaining point estimates of parameters that contribute to interaction strength magnitudes, leaving the characterization of uncertainty associated with those estimates unconsidered. We consider a means of characterizing the uncertainty of a generalist predator's interaction strengths by formulating an observational method for estimating a predator's prey-specific per capita attack rates as a Bayesian statistical model. This formulation permits the explicit incorporation of multiple sources of uncertainty. A key insight is the informative nature of several so-called non-informative priors that have been used in modeling the sparse data typical of predator feeding surveys. We introduce to ecology a new neutral prior and provide evidence for its superior performance. We use a case study to consider the attack rates in a New Zealand intertidal whelk predator, and we illustrate not only that Bayesian point estimates can be made to correspond with those obtained by frequentist approaches, but also that estimation uncertainty as described by 95% intervals is more useful and biologically realistic using the Bayesian method. In particular, unlike in bootstrap confidence intervals, the lower bounds of the Bayesian posterior intervals for attack rates do not include zero when a predator-prey interaction is in fact observed. We conclude that the Bayesian framework provides a straightforward, probabilistic characterization of interaction strength uncertainty, enabling future considerations of both the deterministic and stochastic drivers of interaction strength and their impact on food webs.

Embedding ecosystem services in coastal planning leads to better outcomes for people and nature.

PubMed

Arkema, Katie K; Verutes, Gregory M; Wood, Spencer A; Clarke-Samuels, Chantalle; Rosado, Samir; Canto, Maritza; Rosenthal, Amy; Ruckelshaus, Mary; Guannel, Gregory; Toft, Jodie; Faries, Joe; Silver, Jessica M; Griffin, Robert; Guerry, Anne D

2015-06-16

Recent calls for ocean planning envision informed management of social and ecological systems to sustain delivery of ecosystem services to people. However, until now, no coastal and marine planning process has applied an ecosystem-services framework to understand how human activities affect the flow of benefits, to create scenarios, and to design a management plan. We developed models that quantify services provided by corals, mangroves, and seagrasses. We used these models within an extensive engagement process to design a national spatial plan for Belize's coastal zone. Through iteration of modeling and stakeholder engagement, we developed a preferred plan, currently under formal consideration by the Belizean government. Our results suggest that the preferred plan will lead to greater returns from coastal protection and tourism than outcomes from scenarios oriented toward achieving either conservation or development goals. The plan will also reduce impacts to coastal habitat and increase revenues from lobster fishing relative to current management. By accounting for spatial variation in the impacts of coastal and ocean activities on benefits that ecosystems provide to people, our models allowed stakeholders and policymakers to refine zones of human use. The final version of the preferred plan improved expected coastal protection by >25% and more than doubled the revenue from fishing, compared with earlier versions based on stakeholder preferences alone. Including outcomes in terms of ecosystem-service supply and value allowed for explicit consideration of multiple benefits from oceans and coasts that typically are evaluated separately in management decisions.

Improving resource allocation decisions for health and HIV programmes in South Africa: Bioethical, cost-effectiveness and health diplomacy considerations.

PubMed

Kevany, Sebastian; Benatar, Solomon R; Fleischer, Theodore

2013-01-01

The escalating expenditure on patients with HIV/AIDS within an inadequately funded public health system is tending towards crowding out care for patients with non-HIV illnesses. Priority-setting decisions are thus required and should increasingly be based on an explicit, transparent and accountable process to facilitate sustainability. South Africa's public health system is eroding, even though the government has received extensive donor financing for specific conditions, such as HIV/AIDS. The South African government's 2007 HIV plan anticipated costs exceeding 20% of the annual health budget with a strong focus on treatment interventions, while the recently announced 2012-2016 National Strategic HIV plan could cost up to US$16 billion. Conversely, the total non-HIV health budget has remained static in recent years, effectively reducing the supply of health care for other diseases. While the South African government cannot meet all demands for health care simultaneously, health funders should attempt to allocate health resources in a fair, efficient, transparent and accountable manner, in order to ensure that publicly funded health care is delivered in a reasonable and non-discriminatory fashion. We recommend a process for resource allocation that includes ethical, economic, legal and policy considerations. This process, adapted for use by South Africa's policy-makers, could bring health, political, economic and ethical gains, whilst allaying a social crisis as mounting treatment commitments generated by HIV have the potential to overwhelm the health system.

Cross scale interactions, nonlinearities, and forecasting catastrophic events

USGS Publications Warehouse

Peters, Debra P.C.; Pielke, Roger A.; Bestelmeyer, Brandon T.; Allen, Craig D.; Munson-McGee, Stuart; Havstad, Kris M.

2004-01-01

Catastrophic events share characteristic nonlinear behaviors that are often generated by cross-scale interactions and feedbacks among system elements. These events result in surprises that cannot easily be predicted based on information obtained at a single scale. Progress on catastrophic events has focused on one of the following two areas: nonlinear dynamics through time without an explicit consideration of spatial connectivity [Holling, C. S. (1992) Ecol. Monogr. 62, 447–502] or spatial connectivity and the spread of contagious processes without a consideration of cross-scale interactions and feedbacks [Zeng, N., Neeling, J. D., Lau, L. M. & Tucker, C. J. (1999) Science 286, 1537–1540]. These approaches rarely have ventured beyond traditional disciplinary boundaries. We provide an interdisciplinary, conceptual, and general mathematical framework for understanding and forecasting nonlinear dynamics through time and across space. We illustrate the generality and usefulness of our approach by using new data and recasting published data from ecology (wildfires and desertification), epidemiology (infectious diseases), and engineering (structural failures). We show that decisions that minimize the likelihood of catastrophic events must be based on cross-scale interactions, and such decisions will often be counterintuitive. Given the continuing challenges associated with global change, approaches that cross disciplinary boundaries to include interactions and feedbacks at multiple scales are needed to increase our ability to predict catastrophic events and develop strategies for minimizing their occurrence and impacts. Our framework is an important step in developing predictive tools and designing experiments to examine cross-scale interactions.

Effects of electrostatic interactions on ligand dissociation kinetics

NASA Astrophysics Data System (ADS)

Erbaş, Aykut; de la Cruz, Monica Olvera; Marko, John F.

2018-02-01

We study unbinding of multivalent cationic ligands from oppositely charged polymeric binding sites sparsely grafted on a flat neutral substrate. Our molecular dynamics simulations are suggested by single-molecule studies of protein-DNA interactions. We consider univalent salt concentrations spanning roughly a 1000-fold range, together with various concentrations of excess ligands in solution. To reveal the ionic effects on unbinding kinetics of spontaneous and facilitated dissociation mechanisms, we treat electrostatic interactions both at a Debye-Hückel (DH) (or implicit ions, i.e., use of an electrostatic potential with a prescribed decay length) level and by the more precise approach of considering all ionic species explicitly in the simulations. We find that the DH approach systematically overestimates unbinding rates, relative to the calculations where all ion pairs are present explicitly in solution, although many aspects of the two types of calculation are qualitatively similar. For facilitated dissociation (FD) (acceleration of unbinding by free ligands in solution) explicit-ion simulations lead to unbinding at lower free-ligand concentrations. Our simulations predict a variety of FD regimes as a function of free-ligand and ion concentrations; a particularly interesting regime is at intermediate concentrations of ligands where nonelectrostatic binding strength controls FD. We conclude that explicit-ion electrostatic modeling is an essential component to quantitatively tackle problems in molecular ligand dissociation, including nucleic-acid-binding proteins.

A neurocomputational theory of how explicit learning bootstraps early procedural learning.

PubMed

Paul, Erick J; Ashby, F Gregory

2013-01-01

It is widely accepted that human learning and memory is mediated by multiple memory systems that are each best suited to different requirements and demands. Within the domain of categorization, at least two systems are thought to facilitate learning: an explicit (declarative) system depending largely on the prefrontal cortex, and a procedural (non-declarative) system depending on the basal ganglia. Substantial evidence suggests that each system is optimally suited to learn particular categorization tasks. However, it remains unknown precisely how these systems interact to produce optimal learning and behavior. In order to investigate this issue, the present research evaluated the progression of learning through simulation of categorization tasks using COVIS, a well-known model of human category learning that includes both explicit and procedural learning systems. Specifically, the model's parameter space was thoroughly explored in procedurally learned categorization tasks across a variety of conditions and architectures to identify plausible interaction architectures. The simulation results support the hypothesis that one-way interaction between the systems occurs such that the explicit system "bootstraps" learning early on in the procedural system. Thus, the procedural system initially learns a suboptimal strategy employed by the explicit system and later refines its strategy. This bootstrapping could be from cortical-striatal projections that originate in premotor or motor regions of cortex, or possibly by the explicit system's control of motor responses through basal ganglia-mediated loops.

Higher order explicit symmetric integrators for inseparable forms of coordinates and momenta

NASA Astrophysics Data System (ADS)

Liu, Lei; Wu, Xin; Huang, Guoqing; Liu, Fuyao

2016-06-01

Pihajoki proposed the extended phase-space second-order explicit symmetric leapfrog methods for inseparable Hamiltonian systems. On the basis of this work, we survey a critical problem on how to mix the variables in the extended phase space. Numerical tests show that sequent permutations of coordinates and momenta can make the leapfrog-like methods yield the most accurate results and the optimal long-term stabilized error behaviour. We also present a novel method to construct many fourth-order extended phase-space explicit symmetric integration schemes. Each scheme represents the symmetric production of six usual second-order leapfrogs without any permutations. This construction consists of four segments: the permuted coordinates, triple product of the usual second-order leapfrog without permutations, the permuted momenta and the triple product of the usual second-order leapfrog without permutations. Similarly, extended phase-space sixth, eighth and other higher order explicit symmetric algorithms are available. We used several inseparable Hamiltonian examples, such as the post-Newtonian approach of non-spinning compact binaries, to show that one of the proposed fourth-order methods is more efficient than the existing methods; examples include the fourth-order explicit symplectic integrators of Chin and the fourth-order explicit and implicit mixed symplectic integrators of Zhong et al. Given a moderate choice for the related mixing and projection maps, the extended phase-space explicit symplectic-like methods are well suited for various inseparable Hamiltonian problems. Samples of these problems involve the algorithmic regularization of gravitational systems with velocity-dependent perturbations in the Solar system and post-Newtonian Hamiltonian formulations of spinning compact objects.

Alcohol-Approach Inclinations and Drinking Identity as Predictors of Behavioral Economic Demand for Alcohol

PubMed Central

Ramirez, Jason J.; Dennhardt, Ashley A.; Baldwin, Scott A.; Murphy, James G.; Lindgren, Kristen P.

2016-01-01

Behavioral economic demand curve indices of alcohol consumption reflect decisions to consume alcohol at varying costs. Although these indices predict alcohol-related problems beyond established predictors, little is known about the determinants of elevated demand. Two cognitive constructs that may underlie alcohol demand are alcohol-approach inclinations and drinking identity. The aim of this study was to evaluate implicit and explicit measures of these constructs as predictors of alcohol demand curve indices. College student drinkers (N = 223, 59% female) completed implicit and explicit measures of drinking identity and alcohol-approach inclinations at three timepoints separated by three-month intervals, and completed the Alcohol Purchase Task to assess demand at Time 3. Given no change in our alcohol-approach inclinations and drinking identity measures over time, random intercept-only models were used to predict two demand indices: Amplitude, which represents maximum hypothetical alcohol consumption and expenditures, and Persistence, which represents sensitivity to increasing prices. When modeled separately, implicit and explicit measures of drinking identity and alcohol-approach inclinations positively predicted demand indices. When implicit and explicit measures were included in the same model, both measures of drinking identity predicted Amplitude, but only explicit drinking identity predicted Persistence. In contrast, explicit measures of alcohol-approach inclinations, but not implicit measures, predicted both demand indices. Therefore, there was more support for explicit, versus implicit, measures as unique predictors of alcohol demand. Overall, drinking identity and alcohol-approach inclinations both exhibit positive associations with alcohol demand and represent potentially modifiable cognitive constructs that may underlie elevated demand in college student drinkers. PMID:27379444

Effect of Explicit Evaluation on Neural Connectivity Related to Listening to Unfamiliar Music

PubMed Central

Liu, Chao; Brattico, Elvira; Abu-jamous, Basel; Pereira, Carlos S.; Jacobsen, Thomas; Nandi, Asoke K.

2017-01-01

People can experience different emotions when listening to music. A growing number of studies have investigated the brain structures and neural connectivities associated with perceived emotions. However, very little is known about the effect of an explicit act of judgment on the neural processing of emotionally-valenced music. In this study, we adopted the novel consensus clustering paradigm, called binarisation of consensus partition matrices (Bi-CoPaM), to study whether and how the conscious aesthetic evaluation of the music would modulate brain connectivity networks related to emotion and reward processing. Participants listened to music under three conditions – one involving a non-evaluative judgment, one involving an explicit evaluative aesthetic judgment, and one involving no judgment at all (passive listening only). During non-evaluative attentive listening we obtained auditory-limbic connectivity whereas when participants were asked to decide explicitly whether they liked or disliked the music excerpt, only two clusters of intercommunicating brain regions were found: one including areas related to auditory processing and action observation, and the other comprising higher-order structures involved with visual processing. Results indicate that explicit evaluative judgment has an impact on the neural auditory-limbic connectivity during affective processing of music. PMID:29311874

Biomass and fire dynamics in a temperate forest-grassland mosaic: Integrating multi-species herbivory, climate, and fire with the FireBGCv2/GrazeBGC system

Treesearch

Robert A. Riggs; Robert E. Keane; Norm Cimon; Rachel Cook; Lisa Holsinger; John Cook; Timothy DelCurto; L.Scott Baggett; Donald Justice; David Powell; Martin Vavra; Bridgett Naylor

2015-01-01

Landscape fire succession models (LFSMs) predict spatially-explicit interactions between vegetation succession and disturbance, but these models have yet to fully integrate ungulate herbivory as a driver of their processes. We modified a complex LFSM, FireBGCv2, to include a multi-species herbivory module, GrazeBGC. The system is novel in that it explicitly...

Expert guidelines for the management of Alport syndrome and thin basement membrane nephropathy.

PubMed

Savige, Judy; Gregory, Martin; Gross, Oliver; Kashtan, Clifford; Ding, Jie; Flinter, Frances

2013-02-01

Few prospective, randomized controlled clinical trials address the diagnosis and management of patients with Alport syndrome or thin basement membrane nephropathy. Adult and pediatric nephrologists and geneticists from four continents whose clinical practice focuses on these conditions have developed the following guidelines. The 18 recommendations are based on Level D (Expert opinion without explicit critical appraisal, or based on physiology, bench research, or first principles-National Health Service category) or Level III (Opinions of respected authorities, based on clinical experience, descriptive studies, or reports of expert committees-U.S. Preventive Services Task Force) evidence. The recommendations include the use of genetic testing as the gold standard for the diagnosis of Alport syndrome and the demonstration of its mode of inheritance; the need to identify and follow all affected members of a family with X-linked Alport syndrome, including most mothers of affected males; the treatment of males with X-linked Alport syndrome and individuals with autosomal recessive disease with renin-angiotensin system blockade, possibly even before the onset of proteinuria; discouraging the affected mothers of males with X-linked Alport syndrome from renal donation because of their own risk of kidney failure; and consideration of genetic testing to exclude X-linked Alport syndrome in some individuals with thin basement membrane nephropathy. The authors recognize that as evidence emerges, including data from patient registries, these guidelines will evolve further.

Lab Aliens, Legendary Fossils, and Deadly Science Potions: Views of Science and Scientists from Fifth Graders in a Free-Choice Creative Writing Program

NASA Astrophysics Data System (ADS)

Hellman, Leslie G.

This qualitative study uses children's writing to explore the divide between a conception of Science as a humanistic discipline reliant on creativity, ingenuity and out of the box thinking and a persistent public perception of science and scientists as rigid and methodical. Artifacts reviewed were 506 scripts written during 2014 and 2016 by 5th graders participating in an out-of classroom, mentor supported, free-choice 10-week arts and literacy initiative. 47% (237) of these scripts were found to contain content relating to Science, Scientists, Science Education and the Nature of Science. These 237 scripts were coded for themes; characteristics of named scientist characters were tracked and analyzed. Findings included NOS understandings being expressed by representation of Science and Engineering Practices; Ingenuity being primarily linked to Engineering tasks; common portrayals of science as magical or scientists as villains; and a persistence in negative stereotypes of scientists, including a lack of gender equity amongst the named scientist characters. Findings suggest that representations of scientists in popular culture highly influence the portrayals of scientists constructed by the students. Recommendations to teachers include encouraging explicit consideration of big-picture NOS concepts such as ethics during elementary school and encouraging the replacement of documentary or educational shows with more engaging fictional media.

Methods to elicit probability distributions from experts: a systematic review of reported practice in health technology assessment.

PubMed

Grigore, Bogdan; Peters, Jaime; Hyde, Christopher; Stein, Ken

2013-11-01

Elicitation is a technique that can be used to obtain probability distribution from experts about unknown quantities. We conducted a methodology review of reports where probability distributions had been elicited from experts to be used in model-based health technology assessments. Databases including MEDLINE, EMBASE and the CRD database were searched from inception to April 2013. Reference lists were checked and citation mapping was also used. Studies describing their approach to the elicitation of probability distributions were included. Data was abstracted on pre-defined aspects of the elicitation technique. Reports were critically appraised on their consideration of the validity, reliability and feasibility of the elicitation exercise. Fourteen articles were included. Across these studies, the most marked features were heterogeneity in elicitation approach and failure to report key aspects of the elicitation method. The most frequently used approaches to elicitation were the histogram technique and the bisection method. Only three papers explicitly considered the validity, reliability and feasibility of the elicitation exercises. Judged by the studies identified in the review, reports of expert elicitation are insufficient in detail and this impacts on the perceived usability of expert-elicited probability distributions. In this context, the wider credibility of elicitation will only be improved by better reporting and greater standardisation of approach. Until then, the advantage of eliciting probability distributions from experts may be lost.

Use and misuse of mixed methods in population oral health research: A scoping review.

PubMed

Gupta, A; Keuskamp, D

2018-05-30

Despite the known benefits of a mixed methods approach in health research, little is known of its use in the field of population oral health. To map the extent of literature using a mixed methods approach to examine population oral health outcomes. For a comprehensive search of all the available literature published in the English language, databases including PubMed, Dentistry and Oral Sciences Source (DOSS), CINAHL, Web of Science and EMBASE (including Medline) were searched using a range of keywords from inception to October 2017. Only peer-reviewed, population-based studies of oral health outcomes conducted among non-institutionalised participants and using mixed methods were considered eligible for inclusion. Only nine studies met the inclusion criteria and were included in the review. The most frequent oral health outcome investigated was caries experience. However, most studies lacked a theoretical rationale or framework for using mixed methods, or supporting the use of qualitative data. Concurrent triangulation with a convergent design was the most commonly used mixed methods typology for integrating quantitative and qualitative data. The tools used to collect quantitative and qualitative data were mostly limited to surveys and interviews. With growing complexity recognised in the determinants of oral disease, future studies addressing population oral health outcomes are likely to benefit from the use of mixed methods. Explicit consideration of theoretical framework and methodology will strengthen those investigations. Copyright© 2018 Dennis Barber Ltd.

Cost considerations for long-term ecological monitoring

USGS Publications Warehouse

Caughlan, L.; Oakley, K.L.

2001-01-01

For an ecological monitoring program to be successful over the long-term, the perceived benefits of the information must justify the cost. Financial limitations will always restrict the scope of a monitoring program, hence the program’s focus must be carefully prioritized. Clearly identifying the costs and benefits of a program will assist in this prioritization process, but this is easier said than done. Frequently, the true costs of monitoring are not recognized and are, therefore, underestimated. Benefits are rarely evaluated, because they are difficult to quantify. The intent of this review is to assist the designers and managers of long-term ecological monitoring programs by providing a general framework for building and operating a cost-effective program. Previous considerations of monitoring costs have focused on sampling design optimization. We present cost considerations of monitoring in a broader context. We explore monitoring costs, including both budgetary costs, what dollars are spent on, and economic costs, which include opportunity costs. Often, the largest portion of a monitoring program budget is spent on data collection, and other, critical aspects of the program, such as scientific oversight, training, data management, quality assurance, and reporting, are neglected. Recognizing and budgeting for all program costs is therefore a key factor in a program’s longevity. The close relationship between statistical issues and cost is discussed, highlighting the importance of sampling design, replication and power, and comparing the costs of alternative designs through pilot studies and simulation modeling. A monitoring program development process that includes explicit checkpoints for considering costs is presented. The first checkpoint occurs during the setting of objectives and during sampling design optimization. The last checkpoint occurs once the basic shape of the program is known, and the costs and benefits, or alternatively the cost-effectiveness, of each program element can be evaluated. Moving into the implementation phase without careful evaluation of costs and benefits is risky because if costs are later found to exceed benefits, the program will fail. The costs of development, which can be quite high, will have been largely wasted. Realistic expectations of costs and benefits will help ensure that monitoring programs survive the early, turbulent stages of development and the challenges posed by fluctuating budgets during implementation.

Looking beyond borders: integrating best practices in benefit-risk analysis into the field of food and nutrition.

PubMed

Tijhuis, M J; Pohjola, M V; Gunnlaugsdóttir, H; Kalogeras, N; Leino, O; Luteijn, J M; Magnússon, S H; Odekerken-Schröder, G; Poto, M; Tuomisto, J T; Ueland, O; White, B C; Holm, F; Verhagen, H

2012-01-01

An integrated benefit-risk analysis aims to give guidance in decision situations where benefits do not clearly prevail over risks, and explicit weighing of benefits and risks is thus indicated. The BEPRARIBEAN project aims to advance benefit-risk analysis in the area of food and nutrition by learning from other fields. This paper constitutes the final stage of the project, in which commonalities and differences in benefit-risk analysis are identified between the Food and Nutrition field and other fields, namely Medicines, Food Microbiology, Environmental Health, Economics and Marketing-Finance, and Consumer Perception. From this, ways forward are characterized for benefit-risk analysis in Food and Nutrition. Integrated benefit-risk analysis in Food and Nutrition may advance in the following ways: Increased engagement and communication between assessors, managers, and stakeholders; more pragmatic problem-oriented framing of assessment; accepting some risk; pre- and post-market analysis; explicit communication of the assessment purpose, input and output; more human (dose-response) data and more efficient use of human data; segmenting populations based on physiology; explicit consideration of value judgments in assessment; integration of multiple benefits and risks from multiple domains; explicit recognition of the impact of consumer beliefs, opinions, views, perceptions, and attitudes on behaviour; and segmenting populations based on behaviour; the opportunities proposed here do not provide ultimate solutions; rather, they define a collection of issues to be taken account of in developing methods, tools, practices and policies, as well as refining the regulatory context, for benefit-risk analysis in Food and Nutrition and other fields. Thus, these opportunities will now need to be explored further and incorporated into benefit-risk practice and policy. If accepted, incorporation of these opportunities will also involve a paradigm shift in Food and Nutrition benefit-risk analysis towards conceiving the analysis as a process of creating shared knowledge among all stakeholders. Copyright © 2011 Elsevier Ltd. All rights reserved.

Effect of e-cigarette advertisements and antismoking messages on explicit and implicit attitudes towards tobacco and e-cigarette smoking in 18–65-year-olds: a randomised controlled study protocol

PubMed Central

Albery, Ian P; Frings, Daniel

2017-01-01

Introduction Since the advent of e-cigarettes, e-cigarette advertising has escalated and companies are able to use marketing strategies that are not permissible for tobacco products. Research into the effect of e-cigarette advertising on attitudes towards tobacco and e-cigarettes is in its infancy. To date, no research has compared indirect (implicit) measures of attitude towards e-cigarettes with direct (explicit) measures. Furthermore, little consideration has been given to how viewing online advertisements may have an effect on attitudes towards e-cigarettes or how positive attitudes to e-cigarettes may undermine antismoking public health messages. The objectives of this study are to investigate (1) the relationship between explicit and implicit attitudes towards tobacco and e-cigarettes, (2) the effect of e-cigarette advertising on these attitudes and (3) the effect of these attitudes on the efficacy of antismoking health messages. Methods and analysis In experiment 1 an analysis of covariance will be conducted to determine whether viewing an e-cigarette advertisement, compared with a neutral image, has an effect on implicit or explicit attitudes towards tobacco and e-cigarettes, and if these attitudes differ between smokers, vapers and non-smokers aged 18 - 25 years. In experiment 2, moderation analysis will be conducted to assess whether attitudes towards e-cigarettes moderate the psychological efficacy of antismoking health messages in participants aged 18–65 years. In each experiment, attitudes will be measured preintervention and postintervention and 1 week later (n=150) in participants who are smokers (n=50), vapers (n=50) or non-smokers (n=50). Ethics and dissemination Approval for this study has been given by the London South Bank University’s (LSBU) Research Ethics Committee. The findings of these studies will be submitted for publication and disseminated via conferences. The results will be integrated into course provision for practitioners training at LSBU. PMID:28645957

Optimal Decisions for Organ Exchanges in a Kidney Paired Donation Program.

PubMed

Li, Yijiang; Song, Peter X-K; Zhou, Yan; Leichtman, Alan B; Rees, Michael A; Kalbfleisch, John D

2014-05-01

The traditional concept of barter exchange in economics has been extended in the modern era to the area of living-donor kidney transplantation, where one incompatible donor-candidate pair is matched to another pair with a complementary incompatibility, such that the donor from one pair gives an organ to a compatible candidate in the other pair and vice versa. Kidney paired donation (KPD) programs provide a unique and important platform for living incompatible donor-candidate pairs to exchange organs in order to achieve mutual benefit. In this paper, we propose novel organ allocation strategies to arrange kidney exchanges under uncertainties with advantages, including (i) allowance for a general utility-based evaluation of potential kidney transplants and an explicit consideration of stochastic features inherent in a KPD program; and (ii) exploitation of possible alternative exchanges when the originally planned allocation cannot be fully executed. This allocation strategy is implemented using an integer programming (IP) formulation, and its implication is assessed via a data-based simulation system by tracking an evolving KPD program over a series of match runs. Extensive simulation studies are provided to illustrate our proposed approach.

Bayesian analysis of input uncertainty in hydrological modeling: 2. Application

NASA Astrophysics Data System (ADS)

Kavetski, Dmitri; Kuczera, George; Franks, Stewart W.

2006-03-01

The Bayesian total error analysis (BATEA) methodology directly addresses both input and output errors in hydrological modeling, requiring the modeler to make explicit, rather than implicit, assumptions about the likely extent of data uncertainty. This study considers a BATEA assessment of two North American catchments: (1) French Broad River and (2) Potomac basins. It assesses the performance of the conceptual Variable Infiltration Capacity (VIC) model with and without accounting for input (precipitation) uncertainty. The results show the considerable effects of precipitation errors on the predicted hydrographs (especially the prediction limits) and on the calibrated parameters. In addition, the performance of BATEA in the presence of severe model errors is analyzed. While BATEA allows a very direct treatment of input uncertainty and yields some limited insight into model errors, it requires the specification of valid error models, which are currently poorly understood and require further work. Moreover, it leads to computationally challenging highly dimensional problems. For some types of models, including the VIC implemented using robust numerical methods, the computational cost of BATEA can be reduced using Newton-type methods.

Macroparasite dynamics of migratory host populations.

PubMed

Peacock, Stephanie J; Bouhours, Juliette; Lewis, Mark A; Molnár, Péter K

2018-03-01

Spatial variability in host density is a key factor affecting disease dynamics of wildlife, and yet there are few spatially explicit models of host-macroparasite dynamics. This limits our understanding of parasitism in migratory hosts, whose densities change considerably in both space and time. In this paper, we develop a model for host-macroparasite dynamics that considers the directional movement of host populations and their associated parasites. We include spatiotemporal changes in the mean and variance in parasite burden per host, as well as parasite-mediated host mortality and parasite-mediated migratory ability. Reduced migratory ability with increasing parasitism results in heavily infested hosts halting their migration, and higher parasite burdens in stationary hosts than in moving hosts. Simulations reveal the potential for positive feedbacks between parasite-reduced migratory ability and increasing parasite burdens at infection hotspots, such as stopover sites, that may lead to parasite-induced migratory stalling. This framework could help understand how global change might influence wildlife disease via changes to migratory patterns and parasite demographic rates. Copyright © 2018 Elsevier Inc. All rights reserved.

Drought and resprouting plants

DOE PAGES

Zeppel, Melanie J. B.; Harrison, Sandy P.; Adams, Henry D.; ...

2014-12-17

Many species have the ability to resprout vegetatively after a substantial loss of biomass induced by environmental stress, including drought. Many of the regions characterised by ecosystems where resprouting is common are projected to experience more frequent and intense drought during the 21 st century. However, in assessments of ecosystem response to drought disturbance there has been scant consideration of the resilience and post-drought recovery of resprouting species. Systematic differences in hydraulic and allocation traits suggest that resprouting species are more resilient to drought-stress than nonresprouting species. Evidence suggests that ecosystems dominated by resprouters recover from disturbance more quickly thanmore » ecosystems dominated by nonresprouters. The ability of resprouters to avoid mortality and withstand drought, coupled with their ability to recover rapidly, suggests that the impact of increased drought stress in ecosystems dominated by these species may be small. Furthermore, the strategy of resprouting needs to be modelled explicitly to improve estimates of future climate-change impacts on the carbon cycle, but this will require several important knowledge gaps to be filled before resprouting can be properly implemented.« less

NMR and MD Investigations of Human Galectin-1/Oligosaccharide Complexes

PubMed Central

Meynier, Christophe; Feracci, Mikael; Espeli, Marion; Chaspoul, Florence; Gallice, Philippe; Schiff, Claudine; Guerlesquin, Françoise; Roche, Philippe

2009-01-01

Abstract The specific recognition of carbohydrates by lectins plays a major role in many cellular processes. Galectin-1 belongs to a family of 15 structurally related β-galactoside binding proteins that are able to control a variety of cellular events, including cell cycle regulation, adhesion, proliferation, and apoptosis. The three-dimensional structure of galectin-1 has been solved by x-ray crystallography in the free form and in complex with various carbohydrate ligands. In this work, we used a combination of two-dimensional NMR titration experiments and molecular-dynamics simulations with explicit solvent to study the mode of interaction between human galectin-1 and five galactose-containing ligands. Isothermal titration calorimetry measurements were performed to determine their affinities for galectin-1. The contribution of the different hexopyranose units in the protein-carbohydrate interaction was given particular consideration. Although the galactose moiety of each oligosaccharide is necessary for binding, it is not sufficient by itself. The nature of both the reducing sugar in the disaccharide and the interglycosidic linkage play essential roles in the binding to human galectin-1. PMID:20006954

Drought and resprouting plants.

PubMed

Zeppel, Melanie J B; Harrison, Sandy P; Adams, Henry D; Kelley, Douglas I; Li, Guangqi; Tissue, David T; Dawson, Todd E; Fensham, Rod; Medlyn, Belinda E; Palmer, Anthony; West, Adam G; McDowell, Nate G

2015-04-01

Many species have the ability to resprout vegetatively after a substantial loss of biomass induced by environmental stress, including drought. Many of the regions characterised by ecosystems where resprouting is common are projected to experience more frequent and intense drought during the 21st Century. However, in assessments of ecosystem response to drought disturbance there has been scant consideration of the resilience and post-drought recovery of resprouting species. Systematic differences in hydraulic and allocation traits suggest that resprouting species are more resilient to drought-stress than nonresprouting species. Evidence suggests that ecosystems dominated by resprouters recover from disturbance more quickly than ecosystems dominated by nonresprouters. The ability of resprouters to avoid mortality and withstand drought, coupled with their ability to recover rapidly, suggests that the impact of increased drought stress in ecosystems dominated by these species may be small. The strategy of resprouting needs to be modelled explicitly to improve estimates of future climate-change impacts on the carbon cycle, but this will require several important knowledge gaps to be filled before resprouting can be properly implemented. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

Frequency mode excitations in two-dimensional Hindmarsh-Rose neural networks

NASA Astrophysics Data System (ADS)

Tabi, Conrad Bertrand; Etémé, Armand Sylvin; Mohamadou, Alidou

2017-05-01

In this work, we explicitly show the existence of two frequency regimes in a two-dimensional Hindmarsh-Rose neural network. Each of the regimes, through the semi-discrete approximation, is shown to be described by a two-dimensional complex Ginzburg-Landau equation. The modulational instability phenomenon for the two regimes is studied, with consideration given to the coupling intensities among neighboring neurons. Analytical solutions are also investigated, along with their propagation in the two frequency regimes. These waves, depending on the coupling strength, are identified as breathers, impulses and trains of soliton-like structures. Although the waves in two regimes appear in some common regions of parameters, some phase differences are noticed and the global dynamics of the system is highly influenced by the values of the coupling terms. For some values of such parameters, the high-frequency regime displays modulated trains of waves, while the low-frequency dynamics keeps the original asymmetric character of action potentials. We argue that in a wide range of pathological situations, strong interactions among neurons can be responsible for some pathological states, including schizophrenia and epilepsy.

Eigenvalue sensitivity of sampled time systems operating in closed loop

NASA Astrophysics Data System (ADS)

Bernal, Dionisio

2018-05-01

The use of feedback to create closed-loop eigenstructures with high sensitivity has received some attention in the Structural Health Monitoring field. Although practical implementation is necessarily digital, and thus in sampled time, work thus far has center on the continuous time framework, both in design and in checking performance. It is shown in this paper that the performance in discrete time, at typical sampling rates, can differ notably from that anticipated in the continuous time formulation and that discrepancies can be particularly large on the real part of the eigenvalue sensitivities; a consequence being important error on the (linear estimate) of the level of damage at which closed-loop stability is lost. As one anticipates, explicit consideration of the sampling rate poses no special difficulties in the closed-loop eigenstructure design and the relevant expressions are developed in the paper, including a formula for the efficient evaluation of the derivative of the matrix exponential based on the theory of complex perturbations. The paper presents an easily reproduced numerical example showing the level of error that can result when the discrete time implementation of the controller is not considered.

Sixth Grade Student Self-Regulation in Science

NASA Astrophysics Data System (ADS)

Reid, Lisa J.

The positive relationship between self-regulation and student achievement has been repeatedly supported through research. Key considerations that have resulted from prior research include instructor feedback and explicit expectations, student perception of their control of their progress, accurate self-calibration, reflection, goal-setting, age, and methods by which a cycle which integrates all of these can be put in place. While research provides evidence for that fact that it is possible to support student success in several of these areas, many questions are left as to how guided, active self-regulation impacts students perception of their control over their performance, their ability to accurately assess and act upon their strengths and weaknesses, and, ultimately, their overall progress at different developmental stages. This study intended to provide a better understanding of how guidance in the self-regulation strategies of sixth grade science students can impact their attitudes toward learning. Specifically, this study investigated the question, "What is the effect of active reflection, graphing of grades, and goal setting on sixth-grade students' locus of control and ability to self-regulate?"

Questionnaire design from a cross-cultural perspective: an empirical investigation of Koreans and non-Koreans.

PubMed

Willis, Gordon; Zahnd, Elaine

2007-11-01

A persistent challenge to self-report data across racial, ethnic, or cultural groups is the inherent difficulty of attaining cross-cultural comparability of key measures. The current research study investigated the cross-cultural functioning of health-survey questions presented to four groups: (1) Koreans who were monolingual in Korean; (2) non-Korean native speakers of English; (3) bilingual Koreans interviewed in English, and (4) bilingual Koreans interviewed in Korean. This design allowed us to include those likely to be medically underserved, and to assess both linguistic and cultural barriers to collecting health survey data. A total of 36 cognitive interviews were conducted to identify (a) translation problems; (b) problems of cultural adaptation that impede cross-cultural comparability; and (c) generic problems of questionnaire design that affect all groups. An important category of problems was identified that appeared to result from the interaction of respondent and question characteristics. Such problems can best be assessed through explicit consideration of the socio-cultural backgrounds of survey respondents, as opposed to the more usual focus on details of item translation and wording.

Adaptive on-line prediction of the available power of lithium-ion batteries

NASA Astrophysics Data System (ADS)

Waag, Wladislaw; Fleischer, Christian; Sauer, Dirk Uwe

2013-11-01

In this paper a new approach for prediction of the available power of a lithium-ion battery pack is presented. It is based on a nonlinear battery model that includes current dependency of the battery resistance. It results in an accurate power prediction not only at room temperature, but also at lower temperatures at which the current dependency is substantial. The used model parameters are fully adaptable on-line to the given state of the battery (state of charge, state of health, temperature). This on-line adaption in combination with an explicit consideration of differences between characteristics of individual cells in a battery pack ensures an accurate power prediction under all possible conditions. The proposed trade-off between the number of used cell parameters and the total accuracy as well as the optimized algorithm results in a real-time capability of the method, which is demonstrated on a low-cost 16 bit microcontroller. The verification tests performed on a software-in-the-loop test bench system with four 40 Ah lithium-ion cells show promising results.

Color constancy in 3D-2D face recognition

NASA Astrophysics Data System (ADS)

Meyer, Manuel; Riess, Christian; Angelopoulou, Elli; Evangelopoulos, Georgios; Kakadiaris, Ioannis A.

2013-05-01

Face is one of the most popular biometric modalities. However, up to now, color is rarely actively used in face recognition. Yet, it is well-known that when a person recognizes a face, color cues can become as important as shape, especially when combined with the ability of people to identify the color of objects independent of illuminant color variations. In this paper, we examine the feasibility and effect of explicitly embedding illuminant color information in face recognition systems. We empirically examine the theoretical maximum gain of including known illuminant color to a 3D-2D face recognition system. We also investigate the impact of using computational color constancy methods for estimating the illuminant color, which is then incorporated into the face recognition framework. Our experiments show that under close-to-ideal illumination estimates, one can improve face recognition rates by 16%. When the illuminant color is algorithmically estimated, the improvement is approximately 5%. These results suggest that color constancy has a positive impact on face recognition, but the accuracy of the illuminant color estimate has a considerable effect on its benefits.

Computational Grounded Cognition: a new alliance between grounded cognition and computational modeling

PubMed Central

Pezzulo, Giovanni; Barsalou, Lawrence W.; Cangelosi, Angelo; Fischer, Martin H.; McRae, Ken; Spivey, Michael J.

2013-01-01

Grounded theories assume that there is no central module for cognition. According to this view, all cognitive phenomena, including those considered the province of amodal cognition such as reasoning, numeric, and language processing, are ultimately grounded in (and emerge from) a variety of bodily, affective, perceptual, and motor processes. The development and expression of cognition is constrained by the embodiment of cognitive agents and various contextual factors (physical and social) in which they are immersed. The grounded framework has received numerous empirical confirmations. Still, there are very few explicit computational models that implement grounding in sensory, motor and affective processes as intrinsic to cognition, and demonstrate that grounded theories can mechanistically implement higher cognitive abilities. We propose a new alliance between grounded cognition and computational modeling toward a novel multidisciplinary enterprise: Computational Grounded Cognition. We clarify the defining features of this novel approach and emphasize the importance of using the methodology of Cognitive Robotics, which permits simultaneous consideration of multiple aspects of grounding, embodiment, and situatedness, showing how they constrain the development and expression of cognition. PMID:23346065

Changing our minds: a commentary on `Conceptual change: a discussion of theoretical, methodological and practical challenges for science education'

NASA Astrophysics Data System (ADS)

Mercer, Neil

2008-07-01

This paper begins with a consideration of some important themes dealt with in the paper by Treagust and Duit. These include the relationship between research on conceptual change and educational practice, the significance of emotion and identity in the process of conceptual change, and role of cognitive conflict in motivating change. I then argue that the authors implicitly assert the importance of spoken dialogue as a motor for conceptual change, but do not give it the proper, explicit recognition that it deserves. I first use their own data of transcribed talk to make this point, and then go on to elaborate my case by drawing on other research. Talk amongst students and teacher-student talk are both considered. My conclusion is that while more empirical research is needed to understand how dialogue is involved in conceptual change, available evidence shows very clearly that the role of talk and social interaction is so significant that it cannot be ignored. It is therefore necessary for theoretical accounts to deal with both social (i.e. communicative) and cognitive aspects of conceptual change.

Teaching Small and Thinking Large: Effects of Including Social and Ethical Implications in an Interdisciplinary Nanotechnology Course

PubMed Central

Hoover, Elizabeth; Brown, Phil; Averick, Mara; Kane, Agnes; Hurt, Robert

2013-01-01

One way to ensure that social and ethical implications (SEI) of nanotechnology research are taken into consideration early in research projects is to incorporate ethical concepts into university science education. In this paper, we describe an interdisciplinary nanotechnology university science course and the ways in which the opinions of students regarding the ethical implications of nanotechnology research were influenced by the course. From an SEI perspective, there is value in scientists being aware of the need to make explicit the uncertainties that always exist in scientific and technological research and development. By the end of the class, a majority of the students felt that risks and ethical issues are not well understood by scientists working in nanomaterials, and ethical training was recommended for these scientists. Findings from this study speak to the importance of this type of interdisciplinary class in preparing students for collaborative research and making them aware of issues important to the general public who someday will become consumers of products derived from nanotechnology research. PMID:23585917

Methodological problems in the use of indirect comparisons for evaluating healthcare interventions: survey of published systematic reviews.

PubMed

Song, Fujian; Loke, Yoon K; Walsh, Tanya; Glenny, Anne-Marie; Eastwood, Alison J; Altman, Douglas G

2009-04-03

To investigate basic assumptions and other methodological problems in the application of indirect comparison in systematic reviews of competing healthcare interventions. Survey of published systematic reviews. Inclusion criteria Systematic reviews published between 2000 and 2007 in which an indirect approach had been explicitly used. Identified reviews were assessed for comprehensiveness of the literature search, method for indirect comparison, and whether assumptions about similarity and consistency were explicitly mentioned. The survey included 88 review reports. In 13 reviews, indirect comparison was informal. Results from different trials were naively compared without using a common control in six reviews. Adjusted indirect comparison was usually done using classic frequentist methods (n=49) or more complex methods (n=18). The key assumption of trial similarity was explicitly mentioned in only 40 of the 88 reviews. The consistency assumption was not explicit in most cases where direct and indirect evidence were compared or combined (18/30). Evidence from head to head comparison trials was not systematically searched for or not included in nine cases. Identified methodological problems were an unclear understanding of underlying assumptions, inappropriate search and selection of relevant trials, use of inappropriate or flawed methods, lack of objective and validated methods to assess or improve trial similarity, and inadequate comparison or inappropriate combination of direct and indirect evidence. Adequate understanding of basic assumptions underlying indirect and mixed treatment comparison is crucial to resolve these methodological problems. APPENDIX 1: PubMed search strategy. APPENDIX 2: Characteristics of identified reports. APPENDIX 3: Identified studies. References of included studies.

Application of a sensitivity analysis technique to high-order digital flight control systems

NASA Technical Reports Server (NTRS)

Paduano, James D.; Downing, David R.

1987-01-01

A sensitivity analysis technique for multiloop flight control systems is studied. This technique uses the scaled singular values of the return difference matrix as a measure of the relative stability of a control system. It then uses the gradients of these singular values with respect to system and controller parameters to judge sensitivity. The sensitivity analysis technique is first reviewed; then it is extended to include digital systems, through the derivation of singular-value gradient equations. Gradients with respect to parameters which do not appear explicitly as control-system matrix elements are also derived, so that high-order systems can be studied. A complete review of the integrated technique is given by way of a simple example: the inverted pendulum problem. The technique is then demonstrated on the X-29 control laws. Results show linear models of real systems can be analyzed by this sensitivity technique, if it is applied with care. A computer program called SVA was written to accomplish the singular-value sensitivity analysis techniques. Thus computational methods and considerations form an integral part of many of the discussions. A user's guide to the program is included. The SVA is a fully public domain program, running on the NASA/Dryden Elxsi computer.

Mini-Mental State Exam performance of older African Americans: effect of age, gender, education, hypertension, diabetes, and the inclusion of serial 7s subtraction versus "world" backward on score.

PubMed

Hawkins, Keith A; Cromer, Jennifer R; Piotrowski, Andrea S; Pearlson, Godfrey D

2011-11-01

The Mini-Mental State Exam (MMSE) is a clinically ubiquitous yet incompletely standardized instrument. Though the test offers considerable examiner leeway, little data exist on the normative consequences of common administration variations. We sought to: (a) determine the effects of education, age, gender, health status, and a common administration variation (serial 7s subtraction vs. "world" spelled backward) on MMSE score within a minority sample, (b) provide normative data stratified on the most empirically relevant bases, and (c) briefly address item failure rates. African American citizens (N = 298) aged 55-87 living independently in the community were recruited by advertisement, community recruitment, and word of mouth. Total score with "world" spelled backward exceeded total score with serial 7s subtraction across all levels of education, replicating findings in Caucasian samples. Education is the primary source of variance on MMSE score, followed by age. In this cohort, women out-performed men when "world" spelled backward was included, but there was no gender effect when serial 7s subtraction was included in MMSE total score. To ensure an appropriate interpretation of MMSE scores, reports, whether clinical or in publications of research findings, should be explicit regarding the administration method. Stratified normative data are provided.

Ecosystem Services in Agricultural Landscapes: A Spatially Explicit Approach to Support Sustainable Soil Management

PubMed Central

Crossman, Neville D.; MacEwan, Richard J.; Wallace, D. Dugal; Bennett, Lauren T.

2014-01-01

Soil degradation has been associated with a lack of adequate consideration of soil ecosystem services. We demonstrate a broadly applicable method for mapping changes in the supply of two priority soil ecosystem services to support decisions about sustainable land-use configurations. We used a landscape-scale study area of 302 km2 in northern Victoria, south-eastern Australia, which has been cleared for intensive agriculture. Indicators representing priority soil services (soil carbon sequestration and soil water storage) were quantified and mapped under both a current and a future 25-year land-use scenario (the latter including a greater diversity of land uses and increased perennial crops and irrigation). We combined diverse methods, including soil analysis using mid-infrared spectroscopy, soil biophysical modelling, and geostatistical interpolation. Our analysis suggests that the future land-use scenario would increase the landscape-level supply of both services over 25 years. Soil organic carbon content and water storage to 30 cm depth were predicted to increase by about 11% and 22%, respectively. Our service maps revealed the locations of hotspots, as well as potential trade-offs in service supply under new land-use configurations. The study highlights the need to consider diverse land uses in sustainable management of soil services in changing agricultural landscapes. PMID:24616632

Ecosystem services in agricultural landscapes: a spatially explicit approach to support sustainable soil management.

PubMed

Forouzangohar, Mohsen; Crossman, Neville D; MacEwan, Richard J; Wallace, D Dugal; Bennett, Lauren T

2014-01-01

Soil degradation has been associated with a lack of adequate consideration of soil ecosystem services. We demonstrate a broadly applicable method for mapping changes in the supply of two priority soil ecosystem services to support decisions about sustainable land-use configurations. We used a landscape-scale study area of 302 km(2) in northern Victoria, south-eastern Australia, which has been cleared for intensive agriculture. Indicators representing priority soil services (soil carbon sequestration and soil water storage) were quantified and mapped under both a current and a future 25-year land-use scenario (the latter including a greater diversity of land uses and increased perennial crops and irrigation). We combined diverse methods, including soil analysis using mid-infrared spectroscopy, soil biophysical modelling, and geostatistical interpolation. Our analysis suggests that the future land-use scenario would increase the landscape-level supply of both services over 25 years. Soil organic carbon content and water storage to 30 cm depth were predicted to increase by about 11% and 22%, respectively. Our service maps revealed the locations of hotspots, as well as potential trade-offs in service supply under new land-use configurations. The study highlights the need to consider diverse land uses in sustainable management of soil services in changing agricultural landscapes.

Towards legitimacy of the solar geoengineering research enterprise

PubMed Central

Stephens, Jennie C.

2018-01-01

Mounting evidence that even aggressive reductions in net emissions of greenhouse gases will be insufficient to limit global climate risks is increasing calls for atmospheric experiments to better understand the risks and implications of also deploying solar geoengineering technologies to reflect sunlight and rapidly lower surface temperatures. But solar geoengineering research itself poses significant environmental and geopolitical risks. Given limited societal awareness and public dialogue about this climate response option, conducting such experiments without meaningful societal engagement could galvanize opposition to solar geoengineering research from civil society, including the most climate vulnerable communities who are among its intended beneficiaries. Here, we explore whether and how a solar geoengineering research enterprise might be developed in a way that promotes legitimacy as well as scientific credibility and policy relevance. We highlight the distinctive responsibilities of researchers and research funders to ensure that solar geoengineering research proposals are subject to legitimate societal review and scrutiny, recommend steps they can take to strive towards legitimacy and call on them to be explicitly open to multiple potential outcomes, including the societal rejection or considerable alteration of the solar geoengineering research enterprise. This article is part of the theme issue ‘The Paris Agreement: understanding the physical and social challenges for a warming world of 1.5°C above pre-industrial levels'. PMID:29610369

Illuminating the Context and Circumstances of Male Couples Establishing a Sexual Agreement in Their Relationship

PubMed Central

Mitchell, Jason W.; Lee, Ji-Young; Woodyatt, Cory; Bauermeister, José; Sullivan, Patrick; Stephenson, Rob

2016-01-01

A sexual agreement is an explicit mutual understanding made between two partners about which sexual and relational behaviors they agree to engage in within and/or outside of their relationship. Factors that prompt male couples to form a sexual agreement and under what circumstances remain underinvestigated, yet are important considerations for development of couples-based sexual health and HIV prevention interventions. By using thematic analysis with qualitative dyadic data from a convenience sample of 29 HIV-negative male couples, the present study sought to describe the timing and investigate the context and circumstances that led male couples to establish a sexual agreement in their relationship at both the individual and couple levels, and by agreement type. Themes identified for when a sexual agreement was formed included within the first 6 months, and after 6 months in the relationship. Themes related to context and circumstances of couples’ sexual agreement formation were as follows: (a) desire for sexual exploration, (b) arisen circumstances or events with other men, (c) influences from past relationship(s) and/or other couples (i.e., peers), (d) to protect against HIV, and (e) purposeful conversations versus understood. Findings suggest HIV prevention efforts should include skill-building exercises to help improve communication and promote sex positivity within male couples’ relationships. PMID:27334670

Design for Survivability: An Approach to Assured Autonomy

NASA Technical Reports Server (NTRS)

Alexandrov, Natalia M.; Ozoroski, Thomas A.

2016-01-01

Rapidly expanding unmanned air traffic includes and will continue to include non-cooperative participants. Non-cooperative behavior may be due to technical failure, a lack of appropriate equipment, a careless or malicious operator. Regardless of the cause, the outcome remains: growing density of non-cooperative traffic will increase the risk of collision between unmanned vehicles and aircraft carrying humans. As a result, the degraded safety of airspace may limit access to airspace, with adverse consequences for the traveling public and the economy. Because encounters with small non-cooperative objects, such as birds or wayward drones, can happen too rapidly for an external control system to mitigate them, it is imperative that the aircraft that carry humans survive encounters with non-cooperative vehicles. To-date, design for survivability has been practiced explicitly in the military domain. Survivability against collisions in civil aviation has been limited to tolerances against bird strikes; and these tolerances have proved inadequate on occasion. The growing risk of collision with unmanned vehicles now requires the development of survivability discipline for civilian transport aircraft. The new discipline must be infused into multidisciplinary design methods, on par with traditional disciplines. In this paper, we report on a preliminary study of survivability considerations for the civil aviation domain.

Towards legitimacy of the solar geoengineering research enterprise.

PubMed

Frumhoff, Peter C; Stephens, Jennie C

2018-05-13

Mounting evidence that even aggressive reductions in net emissions of greenhouse gases will be insufficient to limit global climate risks is increasing calls for atmospheric experiments to better understand the risks and implications of also deploying solar geoengineering technologies to reflect sunlight and rapidly lower surface temperatures. But solar geoengineering research itself poses significant environmental and geopolitical risks. Given limited societal awareness and public dialogue about this climate response option, conducting such experiments without meaningful societal engagement could galvanize opposition to solar geoengineering research from civil society, including the most climate vulnerable communities who are among its intended beneficiaries. Here, we explore whether and how a solar geoengineering research enterprise might be developed in a way that promotes legitimacy as well as scientific credibility and policy relevance. We highlight the distinctive responsibilities of researchers and research funders to ensure that solar geoengineering research proposals are subject to legitimate societal review and scrutiny, recommend steps they can take to strive towards legitimacy and call on them to be explicitly open to multiple potential outcomes, including the societal rejection or considerable alteration of the solar geoengineering research enterprise.This article is part of the theme issue 'The Paris Agreement: understanding the physical and social challenges for a warming world of 1.5°C above pre-industrial levels'. © 2018 The Authors.

A capacity-building conceptual framework for public health nutrition practice.

PubMed

Baillie, Elizabeth; Bjarnholt, Christel; Gruber, Marlies; Hughes, Roger

2009-08-01

To describe a conceptual framework to assist in the application of capacity-building principles to public health nutrition practice. A review of the literature and consideration of the determinants of effective public health nutrition practice has been used to inform the development of a conceptual framework for capacity building in the context of public health nutrition practice. The limited literature supports a greater integration and application of capacity-building strategies and principles in public health nutrition practice, and that this application should be overt and strategic. A framework is proposed that identifies a number of determinants of capacity for effective public health nutrition action. The framework represents the key foundations for building capacity including leadership, resourcing and intelligence. Five key strategic domains supported by these foundation elements, including partnerships, organisational development, project management quality, workforce development and community development, are proposed. This framework can be used to assist the systematic assessment, development and evaluation of capacity-building activity within public health nutrition practice. Capacity building is a strategy within public health nutrition practice that needs to be central to public health nutrition intervention management. The present paper defines, contextualises and outlines a framework for integrating and making explicit the importance of capacity building within public health nutrition practice at many levels.

Towards legitimacy of the solar geoengineering research enterprise

NASA Astrophysics Data System (ADS)

Frumhoff, Peter C.; Stephens, Jennie C.

2018-05-01

Mounting evidence that even aggressive reductions in net emissions of greenhouse gases will be insufficient to limit global climate risks is increasing calls for atmospheric experiments to better understand the risks and implications of also deploying solar geoengineering technologies to reflect sunlight and rapidly lower surface temperatures. But solar geoengineering research itself poses significant environmental and geopolitical risks. Given limited societal awareness and public dialogue about this climate response option, conducting such experiments without meaningful societal engagement could galvanize opposition to solar geoengineering research from civil society, including the most climate vulnerable communities who are among its intended beneficiaries. Here, we explore whether and how a solar geoengineering research enterprise might be developed in a way that promotes legitimacy as well as scientific credibility and policy relevance. We highlight the distinctive responsibilities of researchers and research funders to ensure that solar geoengineering research proposals are subject to legitimate societal review and scrutiny, recommend steps they can take to strive towards legitimacy and call on them to be explicitly open to multiple potential outcomes, including the societal rejection or considerable alteration of the solar geoengineering research enterprise. This article is part of the theme issue `The Paris Agreement: understanding the physical and social challenges for a warming world of 1.5°C above pre-industrial levels'.

Spatially explicit estimation of heat stress-related impacts of climate change on the milk production of dairy cows in the United Kingdom.

PubMed

Fodor, Nándor; Foskolos, Andreas; Topp, Cairistiona F E; Moorby, Jon M; Pásztor, László; Foyer, Christine H

2018-01-01

Dairy farming is one the most important sectors of United Kingdom (UK) agriculture. It faces major challenges due to climate change, which will have direct impacts on dairy cows as a result of heat stress. In the absence of adaptations, this could potentially lead to considerable milk loss. Using an 11-member climate projection ensemble, as well as an ensemble of 18 milk loss estimation methods, temporal changes in milk production of UK dairy cows were estimated for the 21st century at a 25 km resolution in a spatially-explicit way. While increases in UK temperatures are projected to lead to relatively low average annual milk losses, even for southern UK regions (<180 kg/cow), the 'hottest' 25×25 km grid cell in the hottest year in the 2090s, showed an annual milk loss exceeding 1300 kg/cow. This figure represents approximately 17% of the potential milk production of today's average cow. Despite the potential considerable inter-annual variability of annual milk loss, as well as the large differences between the climate projections, the variety of calculation methods is likely to introduce even greater uncertainty into milk loss estimations. To address this issue, a novel, more biologically-appropriate mechanism of estimating milk loss is proposed that provides more realistic future projections. We conclude that South West England is the region most vulnerable to climate change economically, because it is characterised by a high dairy herd density and therefore potentially high heat stress-related milk loss. In the absence of mitigation measures, estimated heat stress-related annual income loss for this region by the end of this century may reach £13.4M in average years and £33.8M in extreme years.

Memory-Efficient Analysis of Dense Functional Connectomes.

PubMed

Loewe, Kristian; Donohue, Sarah E; Schoenfeld, Mircea A; Kruse, Rudolf; Borgelt, Christian

2016-01-01

The functioning of the human brain relies on the interplay and integration of numerous individual units within a complex network. To identify network configurations characteristic of specific cognitive tasks or mental illnesses, functional connectomes can be constructed based on the assessment of synchronous fMRI activity at separate brain sites, and then analyzed using graph-theoretical concepts. In most previous studies, relatively coarse parcellations of the brain were used to define regions as graphical nodes. Such parcellated connectomes are highly dependent on parcellation quality because regional and functional boundaries need to be relatively consistent for the results to be interpretable. In contrast, dense connectomes are not subject to this limitation, since the parcellation inherent to the data is used to define graphical nodes, also allowing for a more detailed spatial mapping of connectivity patterns. However, dense connectomes are associated with considerable computational demands in terms of both time and memory requirements. The memory required to explicitly store dense connectomes in main memory can render their analysis infeasible, especially when considering high-resolution data or analyses across multiple subjects or conditions. Here, we present an object-based matrix representation that achieves a very low memory footprint by computing matrix elements on demand instead of explicitly storing them. In doing so, memory required for a dense connectome is reduced to the amount needed to store the underlying time series data. Based on theoretical considerations and benchmarks, different matrix object implementations and additional programs (based on available Matlab functions and Matlab-based third-party software) are compared with regard to their computational efficiency. The matrix implementation based on on-demand computations has very low memory requirements, thus enabling analyses that would be otherwise infeasible to conduct due to insufficient memory. An open source software package containing the created programs is available for download.

Memory-Efficient Analysis of Dense Functional Connectomes

PubMed Central

Loewe, Kristian; Donohue, Sarah E.; Schoenfeld, Mircea A.; Kruse, Rudolf; Borgelt, Christian

2016-01-01

The functioning of the human brain relies on the interplay and integration of numerous individual units within a complex network. To identify network configurations characteristic of specific cognitive tasks or mental illnesses, functional connectomes can be constructed based on the assessment of synchronous fMRI activity at separate brain sites, and then analyzed using graph-theoretical concepts. In most previous studies, relatively coarse parcellations of the brain were used to define regions as graphical nodes. Such parcellated connectomes are highly dependent on parcellation quality because regional and functional boundaries need to be relatively consistent for the results to be interpretable. In contrast, dense connectomes are not subject to this limitation, since the parcellation inherent to the data is used to define graphical nodes, also allowing for a more detailed spatial mapping of connectivity patterns. However, dense connectomes are associated with considerable computational demands in terms of both time and memory requirements. The memory required to explicitly store dense connectomes in main memory can render their analysis infeasible, especially when considering high-resolution data or analyses across multiple subjects or conditions. Here, we present an object-based matrix representation that achieves a very low memory footprint by computing matrix elements on demand instead of explicitly storing them. In doing so, memory required for a dense connectome is reduced to the amount needed to store the underlying time series data. Based on theoretical considerations and benchmarks, different matrix object implementations and additional programs (based on available Matlab functions and Matlab-based third-party software) are compared with regard to their computational efficiency. The matrix implementation based on on-demand computations has very low memory requirements, thus enabling analyses that would be otherwise infeasible to conduct due to insufficient memory. An open source software package containing the created programs is available for download. PMID:27965565

Projecting biodiversity and wood production in future forest landscapes: 15 key modeling considerations.

PubMed

Felton, Adam; Ranius, Thomas; Roberge, Jean-Michel; Öhman, Karin; Lämås, Tomas; Hynynen, Jari; Juutinen, Artti; Mönkkönen, Mikko; Nilsson, Urban; Lundmark, Tomas; Nordin, Annika

2017-07-15

A variety of modeling approaches can be used to project the future development of forest systems, and help to assess the implications of different management alternatives for biodiversity and ecosystem services. This diversity of approaches does however present both an opportunity and an obstacle for those trying to decide which modeling technique to apply, and interpreting the management implications of model output. Furthermore, the breadth of issues relevant to addressing key questions related to forest ecology, conservation biology, silviculture, economics, requires insights stemming from a number of distinct scientific disciplines. As forest planners, conservation ecologists, ecological economists and silviculturalists, experienced with modeling trade-offs and synergies between biodiversity and wood biomass production, we identified fifteen key considerations relevant to assessing the pros and cons of alternative modeling approaches. Specifically we identified key considerations linked to study question formulation, modeling forest dynamics, forest processes, study landscapes, spatial and temporal aspects, and the key response metrics - biodiversity and wood biomass production, as well as dealing with trade-offs and uncertainties. We also provide illustrative examples from the modeling literature stemming from the key considerations assessed. We use our findings to reiterate the need for explicitly addressing and conveying the limitations and uncertainties of any modeling approach taken, and the need for interdisciplinary research efforts when addressing the conservation of biodiversity and sustainable use of environmental resources. Copyright © 2017 Elsevier Ltd. All rights reserved.

Malodorous consequences: what comprises negligence in anosmia litigation?

PubMed

Svider, Peter F; Mauro, Andrew C; Eloy, Jean Anderson; Setzen, Michael; Carron, Michael A; Folbe, Adam J

2014-03-01

Our objectives were to evaluate factors raised in malpractice litigation in which plaintiffs alleged that physician negligence led to olfactory dysfunction. We analyzed publically available federal and court records using Westlaw, a widely used computerized legal database. Pertinent jury verdicts and settlements were comprehensively examined for alleged causes of malpractice (including procedures for iatrogenic causes), defendant specialty, patient demographics, and other factors raised in legal proceedings. Of 25 malpractice proceedings meeting inclusion criteria, 60.0% were resolved for the defendant, 12.0% were settled, and 28.0% had jury-awarded damages. Median payments were significant ($300,000 and $412,500 for settlements and awards, respectively). Otolaryngologists were the most frequently named defendants (68.0%), with the majority of iatrogenic cases (55.0%) related to rhinologic procedures. Associated medical events accompanying anosmia included dysgeusia, cerebrospinal fluid leaks, and meningitis. Other alleged factors included requiring additional surgery (80.0%), unnecessary procedures (47.4% of iatrogenic procedural cases), untimely diagnosis leading to anosmia (44.0%), inadequate informed consent (35.0%), dysgeusia (56.0%), and psychological sequelae (24.0%). Olfactory dysfunction can adversely affect quality of life and thus is a potential area for malpractice litigation. This is particularly true for iatrogenic causes of anosmia, especially following rhinologic procedures. Settlements and damages awarded were considerable, making an understanding of factors detailed in this analysis of paramount importance for the practicing otolaryngologist. This analysis reinforces the importance of explicitly including anosmia in a comprehensive informed consent process for any rhinologic procedure. © 2013 ARS-AAOA, LLC.

Corruption of accuracy and efficiency of Markov chain Monte Carlo simulation by inaccurate numerical implementation of conceptual hydrologic models

NASA Astrophysics Data System (ADS)

Schoups, G.; Vrugt, J. A.; Fenicia, F.; van de Giesen, N. C.

2010-10-01

Conceptual rainfall-runoff models have traditionally been applied without paying much attention to numerical errors induced by temporal integration of water balance dynamics. Reliance on first-order, explicit, fixed-step integration methods leads to computationally cheap simulation models that are easy to implement. Computational speed is especially desirable for estimating parameter and predictive uncertainty using Markov chain Monte Carlo (MCMC) methods. Confirming earlier work of Kavetski et al. (2003), we show here that the computational speed of first-order, explicit, fixed-step integration methods comes at a cost: for a case study with a spatially lumped conceptual rainfall-runoff model, it introduces artificial bimodality in the marginal posterior parameter distributions, which is not present in numerically accurate implementations of the same model. The resulting effects on MCMC simulation include (1) inconsistent estimates of posterior parameter and predictive distributions, (2) poor performance and slow convergence of the MCMC algorithm, and (3) unreliable convergence diagnosis using the Gelman-Rubin statistic. We studied several alternative numerical implementations to remedy these problems, including various adaptive-step finite difference schemes and an operator splitting method. Our results show that adaptive-step, second-order methods, based on either explicit finite differencing or operator splitting with analytical integration, provide the best alternative for accurate and efficient MCMC simulation. Fixed-step or adaptive-step implicit methods may also be used for increased accuracy, but they cannot match the efficiency of adaptive-step explicit finite differencing or operator splitting. Of the latter two, explicit finite differencing is more generally applicable and is preferred if the individual hydrologic flux laws cannot be integrated analytically, as the splitting method then loses its advantage.

Algorithms for the explicit computation of Penrose diagrams

NASA Astrophysics Data System (ADS)

Schindler, J. C.; Aguirre, A.

2018-05-01

An algorithm is given for explicitly computing Penrose diagrams for spacetimes of the form . The resulting diagram coordinates are shown to extend the metric continuously and nondegenerately across an arbitrary number of horizons. The method is extended to include piecewise approximations to dynamically evolving spacetimes using a standard hypersurface junction procedure. Examples generated by an implementation of the algorithm are shown for standard and new cases. In the appendix, this algorithm is compared to existing methods.

Three-dimensional compact explicit-finite difference time domain scheme with density variation

NASA Astrophysics Data System (ADS)

Tsuchiya, Takao; Maruta, Naoki

2018-07-01

In this paper, the density variation is implemented in the three-dimensional compact-explicit finite-difference time-domain (CE-FDTD) method. The formulation is first developed based on the continuity equation and the equation of motion, which include the density. Some numerical demonstrations are performed for the three-dimensional sound wave propagation in a two density layered medium. The numerical results are compared with the theoretical results to verify the proposed formulation.

The Effects of Eliciting Implicit versus Explicit Social Support among Youths Susceptible for Late-Onset Smoking

PubMed Central

Roberts, Megan E.; Bernstein, Michael H.; Colby, Suzanne M.

2016-01-01

Purpose Adolescents susceptible to late-onset smoking (becoming regular smokers at age 18 or later) are an understudied population. Social support is a promising target for intervention, but it is important to distinguish between implicit social support (reminders that one belongs to a network of valued others) and explicit social support (seeking and receiving advice and emotional solace). This study aimed to test the potential protective influence of implicit and explicit social support on reducing the risk of late-onset smoking. Methods Fifty-eight smoking-susceptible youths (aged 16–18, 45% African American, 55% non-Hispanic White) completed an experimental session that included a video-recording task designed to elicit thoughts about implicit, explicit, or no social support. Youths reported their behavioral willingness and intentions (BW and BI) to smoke immediately following the social support manipulation; a random sample of 39 youths reported again at a 3-week follow-up. Results Following the manipulation, BW and BI for cigarette smoking were significantly higher among youths assigned to the explicit-support condition, compared to those in the implicit-support or control conditions. At follow-up, BW and BI were highest in the explicit-support condition and lowest in the implicit-support condition, but the differences were not significant. Conclusions Overall, findings indicated that for teens susceptible for late-onset smoking, eliciting thoughts about implicit social support produces lower risk for cigarette initiation than does eliciting thoughts about explicit social support. The present results and the video task that yielded them are important to researchers and practitioners interested in reducing the likelihood of late-onset smoking. PMID:27322670

The effects of eliciting implicit versus explicit social support among youths susceptible for late-onset smoking.

PubMed

Roberts, Megan E; Bernstein, Michael H; Colby, Suzanne M

2016-11-01

Adolescents susceptible to late-onset smoking (becoming regular smokers at age 18 or later) are an understudied population. Social support is a promising target for intervention, but it is important to distinguish between implicit social support (reminders that one belongs to a network of valued others) and explicit social support (seeking and receiving advice and emotional solace). This study aimed to test the potential protective influence of implicit and explicit social support on reducing the risk of late-onset smoking. Fifty-eight smoking-susceptible youths (aged 16-18, 45% African American, 55% non-Hispanic White) completed an experimental session that included a video-recording task designed to elicit thoughts about implicit, explicit, or no social support. Youths reported their behavioral willingness and intentions (BW and BI) to smoke immediately following the social support manipulation; a random sample of 39 youths reported again at a 3-week follow-up. Following the manipulation, BW and BI for cigarette smoking were significantly higher among youths assigned to the explicit-support condition, compared to those in the implicit-support or control conditions. At follow-up, BW and BI were highest in the explicit-support condition and lowest in the implicit-support condition, but the differences were not significant. Overall, findings indicated that for teens susceptible for late-onset smoking, eliciting thoughts about implicit social support produces lower risk for cigarette initiation than does eliciting thoughts about explicit social support. The present results and the video task that yielded them are important to researchers and practitioners interested in reducing the likelihood of late-onset smoking. Copyright © 2016 Elsevier Ltd. All rights reserved.

Elementary school science teachers' reflection for nature of science: Workshop of NOS explicit and reflective on force and motion learning activity

NASA Astrophysics Data System (ADS)

Patho, Khanittha; Yuenyong, Chokchai; Chamrat, Suthida

2018-01-01

The nature of science has been part of Thailand's science education curriculum since 2008. However, teachers lack of understanding about the nature of science (NOS) and its teaching, particularly element school science teachers. In 2012, the Science Institute of Thailand MOE, started a project of Elementary Science Teacher Professional Development to enhance their thinking about the Nature of Science. The project aimed to enhance teachers' understanding of NOS, science teaching for explicit and reflective NOS, with the aim of extending their understanding of NOS to other teachers. This project selected 366 educational persons. The group was made up of a teacher and a teacher supervisor from 183 educational areas in 74 provinces all Thailand. The project provided a one week workshop and a year's follow up. The week-long workshop consisted of 11 activities of science teaching for explicit reflection on 8 aspects of NOS. Workshop of NOS explicit and reflective on force and motion learning activity is one of eight activities. This activity provided participants to learn force and motion and NOS from the traditional toy "Bang-Poh". The activity tried to enhance participants to explicit NOS for 5 aspects including empirical basis, subjectivity, creativity, observation and inference, and sociocultural embeddedness. The explicit NOS worksheet provided questions to ask participants to reflect their existing ideas about NOS. The paper examines elementary school science teachers' understanding of NOS from the force and motion learning activity which provided explicit reflection on 5 NOS aspects. An interpretive paradigm was used to analyse the teachers' reflections in a NOS worksheet. The findings indicated that majority of them could reflect about the empirical basis of science and creativity but few reflected on observation and inference, or sociocultural embeddedness. The paper will explain the teachers' NOS thinking and discuss the further enhancing of their understanding and organizing NOS explicit and reflective science teaching.

Solvent Reaction Field Potential inside an Uncharged Globular Protein: A Bridge between Implicit and Explicit Solvent Models?

PubMed Central

Baker, Nathan A.; McCammon, J. Andrew

2008-01-01

The solvent reaction field potential of an uncharged protein immersed in Simple Point Charge/Extended (SPC/E) explicit solvent was computed over a series of molecular dynamics trajectories, intotal 1560 ns of simulation time. A finite, positive potential of 13 to 24 kbTec−1 (where T = 300K), dependent on the geometry of the solvent-accessible surface, was observed inside the biomolecule. The primary contribution to this potential arose from a layer of positive charge density 1.0 Å from the solute surface, on average 0.008 ec/Å3, which we found to be the product of a highly ordered first solvation shell. Significant second solvation shell effects, including additional layers of charge density and a slight decrease in the short-range solvent-solvent interaction strength, were also observed. The impact of these findings on implicit solvent models was assessed by running similar explicit-solvent simulations on the fully charged protein system. When the energy due to the solvent reaction field in the uncharged system is accounted for, correlation between per-atom electrostatic energies for the explicit solvent model and a simple implicit (Poisson) calculation is 0.97, and correlation between per-atom energies for the explicit solvent model and a previously published, optimized Poisson model is 0.99. PMID:17949217

Studies of implicit and explicit solution techniques in transient thermal analysis of structures

NASA Technical Reports Server (NTRS)

Adelman, H. M.; Haftka, R. T.; Robinson, J. C.

1982-01-01

Studies aimed at an increase in the efficiency of calculating transient temperature fields in complex aerospace vehicle structures are reported. The advantages and disadvantages of explicit and implicit algorithms are discussed and a promising set of implicit algorithms with variable time steps, known as GEARIB, is described. Test problems, used for evaluating and comparing various algorithms, are discussed and finite element models of the configurations are described. These problems include a coarse model of the Space Shuttle wing, an insulated frame tst article, a metallic panel for a thermal protection system, and detailed models of sections of the Space Shuttle wing. Results generally indicate a preference for implicit over explicit algorithms for transient structural heat transfer problems when the governing equations are stiff (typical of many practical problems such as insulated metal structures). The effects on algorithm performance of different models of an insulated cylinder are demonstrated. The stiffness of the problem is highly sensitive to modeling details and careful modeling can reduce the stiffness of the equations to the extent that explicit methods may become the best choice. Preliminary applications of a mixed implicit-explicit algorithm and operator splitting techniques for speeding up the solution of the algebraic equations are also described.

Testing the cognitive catalyst model of rumination with explicit and implicit cognitive content.

PubMed

Sova, Christopher C; Roberts, John E

2018-06-01

The cognitive catalyst model posits that rumination and negative cognitive content, such as negative schema, interact to predict depressive affect. Past research has found support for this model using explicit measures of negative cognitive content such as self-report measures of trait self-esteem and dysfunctional attitudes. The present study tested whether these findings would extend to implicit measures of negative cognitive content such as implicit self-esteem, and whether effects would depend on initial mood state and history of depression. Sixty-one undergraduate students selected on the basis of depression history (27 previously depressed; 34 never depressed) completed explicit and implicit measures of negative cognitive content prior to random assignment to a rumination induction followed by a distraction induction or vice versa. Dysphoric affect was measured both before and after these inductions. Analyses revealed that explicit measures, but not implicit measures, interacted with rumination to predict change in dysphoric affect, and these interactions were further moderated by baseline levels of dysphoria. Limitations include the small nonclinical sample and use of a self-report measure of depression history. These findings suggest that rumination amplifies the association between explicit negative cognitive content and depressive affect primarily among people who are already experiencing sad mood. Copyright © 2018 Elsevier Ltd. All rights reserved.

Explicit and spontaneous retrieval of emotional scenes: electrophysiological correlates.

PubMed

Weymar, Mathias; Bradley, Margaret M; El-Hinnawi, Nasryn; Lang, Peter J

2013-10-01

When event-related potentials (ERP) are measured during a recognition task, items that have previously been presented typically elicit a larger late (400-800 ms) positive potential than new items. Recent data, however, suggest that emotional, but not neutral, pictures show ERP evidence of spontaneous retrieval when presented in a free-viewing task (Ferrari, Bradley, Codispoti, Karlsson, & Lang, 2012). In two experiments, we further investigated the brain dynamics of implicit and explicit retrieval. In Experiment 1, brain potentials were measured during a semantic categorization task, which did not explicitly probe episodic memory, but which, like a recognition task, required an active decision and a button press, and were compared to those elicited during recognition and free viewing. Explicit recognition prompted a late enhanced positivity for previously presented, compared with new, pictures regardless of hedonic content. In contrast, only emotional pictures showed an old-new difference when the task did not explicitly probe episodic memory, either when making an active categorization decision regarding picture content, or when simply viewing pictures. In Experiment 2, however, neutral pictures did prompt a significant old-new ERP difference during subsequent free viewing when emotionally arousing pictures were not included in the encoding set. These data suggest that spontaneous retrieval is heightened for salient cues, perhaps reflecting heightened attention and elaborative processing at encoding.

Solvent reaction field potential inside an uncharged globular protein: A bridge between implicit and explicit solvent models?

NASA Astrophysics Data System (ADS)

Cerutti, David S.; Baker, Nathan A.; McCammon, J. Andrew

2007-10-01

The solvent reaction field potential of an uncharged protein immersed in simple point charge/extended explicit solvent was computed over a series of molecular dynamics trajectories, in total 1560ns of simulation time. A finite, positive potential of 13-24 kbTec-1 (where T =300K), dependent on the geometry of the solvent-accessible surface, was observed inside the biomolecule. The primary contribution to this potential arose from a layer of positive charge density 1.0Å from the solute surface, on average 0.008ec/Å3, which we found to be the product of a highly ordered first solvation shell. Significant second solvation shell effects, including additional layers of charge density and a slight decrease in the short-range solvent-solvent interaction strength, were also observed. The impact of these findings on implicit solvent models was assessed by running similar explicit solvent simulations on the fully charged protein system. When the energy due to the solvent reaction field in the uncharged system is accounted for, correlation between per-atom electrostatic energies for the explicit solvent model and a simple implicit (Poisson) calculation is 0.97, and correlation between per-atom energies for the explicit solvent model and a previously published, optimized Poisson model is 0.99.

Are mixed explicit/implicit solvation models reliable for studying phosphate hydrolysis? A comparative study of continuum, explicit and mixed solvation models.

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

Kamerlin, Shina C. L.; Haranczyk, Maciej; Warshel, Arieh

2009-05-01

Phosphate hydrolysis is ubiquitous in biology. However, despite intensive research on this class of reactions, the precise nature of the reaction mechanism remains controversial. In this work, we have examined the hydrolysis of three homologous phosphate diesters. The solvation free energy was simulated by means of either an implicit solvation model (COSMO), hybrid quantum mechanical / molecular mechanical free energy perturbation (QM/MM-FEP) or a mixed solvation model in which N water molecules were explicitly included in the ab initio description of the reacting system (where N=1-3), with the remainder of the solvent being implicitly modelled as a continuum. Here, bothmore » COSMO and QM/MM-FEP reproduce Delta Gobs within an error of about 2kcal/mol. However, we demonstrate that in order to obtain any form of reliable results from a mixed model, it is essential to carefully select the explicit water molecules from short QM/MM runs that act as a model for the true infinite system. Additionally, the mixed models tend to be increasingly inaccurate the more explicit water molecules are placed into the system. Thus, our analysis indicates that this approach provides an unreliable way for modelling phosphate hydrolysis in solution.« less

Explicit and spontaneous retrieval of emotional scenes: Electrophysiological correlates

PubMed Central

Weymar, Mathias; Bradley, Margaret M.; El-Hinnawi, Nasryn; Lang, Peter J.

2014-01-01

When event-related potentials are measured during a recognition task, items that have previously been presented typically elicit a larger late (400–800 ms) positive potential than new items. Recent data, however, suggest that emotional, but not neutral, pictures show ERP evidence of spontaneous retrieval when presented in a free-viewing task (Ferrari, Bradley, Codispoti & Lang, 2012). In two experiments, we further investigated the brain dynamics of implicit and explicit retrieval. In Experiment 1, brain potentials were measured during a semantic categorization task, which did not explicitly probe episodic memory, but which, like a recognition task, required an active decision and a button press, and were compared to those elicited during recognition and free viewing. Explicit recognition prompted a late enhanced positivity for previously presented, compared to new, pictures regardless of hedonic content. In contrast, only emotional pictures showed an old-new difference when the task did not explicitly probe episodic memory, either when either making an active categorization decision regarding picture content, or when simply viewing pictures. In Experiment 2, however, neutral pictures did prompt a significant old-new ERP difference during subsequent free viewing when emotionally arousing pictures were not included in the encoding set. These data suggest that spontaneous retrieval is heightened for salient cues, perhaps reflecting heightened attention and elaborative processing at encoding. PMID:23795588

Studies of implicit and explicit solution techniques in transient thermal analysis of structures

NASA Astrophysics Data System (ADS)

Adelman, H. M.; Haftka, R. T.; Robinson, J. C.

1982-08-01

Studies aimed at an increase in the efficiency of calculating transient temperature fields in complex aerospace vehicle structures are reported. The advantages and disadvantages of explicit and implicit algorithms are discussed and a promising set of implicit algorithms with variable time steps, known as GEARIB, is described. Test problems, used for evaluating and comparing various algorithms, are discussed and finite element models of the configurations are described. These problems include a coarse model of the Space Shuttle wing, an insulated frame tst article, a metallic panel for a thermal protection system, and detailed models of sections of the Space Shuttle wing. Results generally indicate a preference for implicit over explicit algorithms for transient structural heat transfer problems when the governing equations are stiff (typical of many practical problems such as insulated metal structures). The effects on algorithm performance of different models of an insulated cylinder are demonstrated. The stiffness of the problem is highly sensitive to modeling details and careful modeling can reduce the stiffness of the equations to the extent that explicit methods may become the best choice. Preliminary applications of a mixed implicit-explicit algorithm and operator splitting techniques for speeding up the solution of the algebraic equations are also described.

A Phobos-Deimos Mission as an Element of the NASA Mars Design Reference Architecture 5.0

NASA Technical Reports Server (NTRS)

Hoffman, Stephen J.

2011-01-01

NASA has conducted a series of mission studies over the past 25 years examining the eventual exploration of the surface of Mars by humans. The latest version of this evolutionary series of design reference missions/architectures - Design Reference Architecture 5 or DRA-5 - was completed in 2007. This paper examines the implications of including a human mission to explore the moons of Mars and teleoperate robots in various locations, but not to land the human crews on Mars, as an element of this reference architecture. Such a mission has been proposed several times during this same 25 year evolution leading up to the completion of DRA-5 primarily as a mission of testing the in-space vehicles and operations while surface vehicles and landers are under development. But such a precursor or test mission has never been explicitly included as an element of this Architecture. This paper will first summarize the key features of the DRA-5 to provide context for the remainder of the assessment. This will include a description of the in-space vehicles that would be the subject of a shakedown test during the Mars orbital mission. A decision tree will be used to illustrate the factors that will be analyzed, and the sequence in which they will be addressed, for this assessment. The factors that will be analyzed include the type of interplanetary transfer orbit (opposition class versus conjunction class), the type of parking orbit (circular versus elliptical), and the type of propulsion technology (high thrust chemical versus nuclear thermal rocket). The manner in which each of these factors impacts an individual mission will be described. In addition to the direct impact of these factors, additional considerations impacting crew health and overall programmatic outcomes will be discussed. Numerical results for each of the factors in the decision tree will be grouped with derived qualitative impacts from crew health and programmatic consideration. These quantitative and qualitative results will be summarized in a pros/cons table as a summary for this analysis.

The Role Of Nonprofit Hospitals In Identifying And Addressing Health Inequities In Cities.

PubMed

Carroll-Scott, Amy; Henson, Rosie Mae; Kolker, Jennifer; Purtle, Jonathan

2017-06-01

For nonprofit hospitals to maintain their tax-exempt status, the Affordable Care Act requires them to conduct a community health needs assessment, in which they evaluate the health needs of the community they serve, and to create an implementation strategy, in which they propose ways to address these needs. We explored the extent to which nonprofit urban hospitals identified equity among the health needs of their communities and proposed health equity strategies to address this need. We conducted a content analysis of publicly available community health needs assessments and implementation strategies from 179 hospitals in twenty-eight US cities in the period August-December 2016. All of the needs assessments included at least one implicit health equity term (such as disparities , disadvantage , poor , or minorities ), while 65 percent included at least one explicit health equity term ( equity , health equity , inequity , or health inequity ). Thirty-five percent of implementation strategies included one or more explicit health equity terms, but only 9 percent included an explicit activity to promote health equity. While needs assessment reporting requirements have the potential to encourage urban nonprofit hospitals to address health inequities in their communities, hospitals need incentives and additional capacity to invest in strategies that address the underlying structural social and economic conditions that cause health inequities. Project HOPE—The People-to-People Health Foundation, Inc.

The new EU General Data Protection Regulation: what the radiologist should know.

PubMed

2017-06-01

The European Society of Radiology (ESR) informs its membership and its associated Institutional Members about the new General Data Protection Regulation (GDPR) of the European Union (EU,) which will apply from 25 May 2018. Radiologists and radiology departments should be prepared to comply with several new rules for the protection of imaging data. Although the new GDPR applies to all domains of the public and private sectors, some specific derogations are defined for data concerning health, aiming at protecting the rights of data subjects and confidentiality of their personal health data, whilst preserving the benefits of processing data, including digital images for research and public health purposes. Specific new obligations which healthcare providers (including radiologists/radiology departments) should prepare for include data access for patients, rules for data processing including explicit consent of the data subject in the absence of derogations, or technical and organisational safeguards. National health authorities can define exceptions and derogations from certain obligations by means of national law. They will also define sanctions in the form of penalties or fines that may be applicable for organisations of the public and private sector that fail to comply with the rules of the GDPR. • Explicit consent prior to data processing will be necessary. • Explicit consent prior to communication of imaging data will be necessary. • Providing patient access to their personal data, including portability, will be required. • Certain derogations and exceptions exist for healthcare and research. • Additional specific rules may be defined by national law.

New Approaches to Final Cooling

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

Neuffer, David

2014-11-10

A high-energy muon collider scenario require a “final cooling” system that reduces transverse emittances by a factor of ~10 while allowing longitudinal emittance increase. The baseline approach has low-energy transverse cooling within high-field solenoids, with strong longitudinal heating. This approach and its recent simulation are discussed. Alternative approaches which more explicitly include emittance exchange are also presented. Round-to-flat beam transform, transverse slicing, and longitudinal bunch coalescence are possible components of the alternative approach. A more explicit understanding of solenoidal cooling beam dynamics is introduced.

Formulation of boundary conditions for the multigrid acceleration of the Euler and Navier Stokes equations

NASA Technical Reports Server (NTRS)

Jentink, Thomas Neil; Usab, William J., Jr.

1990-01-01

An explicit, Multigrid algorithm was written to solve the Euler and Navier-Stokes equations with special consideration given to the coarse mesh boundary conditions. These are formulated in a manner consistent with the interior solution, utilizing forcing terms to prevent coarse-mesh truncation error from affecting the fine-mesh solution. A 4-Stage Hybrid Runge-Kutta Scheme is used to advance the solution in time, and Multigrid convergence is further enhanced by using local time-stepping and implicit residual smoothing. Details of the algorithm are presented along with a description of Jameson's standard Multigrid method and a new approach to formulating the Multigrid equations.

Free to Choose? Reform, Choice, and Consideration Sets in the English National Health Service.

PubMed

Gaynor, Martin; Propper, Carol; Seiler, Stephan

2016-11-01

Choice in public services is controversial. We exploit a reform in the English National Health Service to assess the effect of removing constraints on patient choice. We estimate a demand model that explicitly captures the removal of the choice constraints imposed on patients. We find that, post-removal, patients became more responsive to clinical quality. This led to a modest reduction in mortality and a substantial increase in patient welfare. The elasticity of demand faced by hospitals increased substantially post- reform and we find evidence that hospitals responded to the enhanced incentives by improving quality. This suggests greater choice can raise quality.

An aerial-photographic assessment of reenacted handcart treks on a section of the Mormon Pioneer National Historic Trail, Fremont County, Wyoming

USGS Publications Warehouse

McDougal, Robert R.; Waltermire, Robert G.; Aldridge, Cameron L.; Germaine, Stephen S.; Nielsen, Scott E.; Nielsen, Charlene C.; Hanson, Leanne; Bowen, Zachary H.

2008-01-01

Based on these results, there are identifiable management considerations. Toilet and rest sites need to be carefully located relative to where sensitive vegetation or soils occur. The analyses presented here indicate that limiting motorized vehicle use needs to be a priority over that of adjusting the number of trekkers. Additionally, monitoring of the Trail from Sixth Crossing to Rock Creek Hollow segment needs to consider explicit management targets, such as minimum acceptable levels of bare ground or trail width, and the establishment of permanent monitoring plots to evaluate targets and measure responses to altered management activities.

Emotion Generation and Emotion Regulation: One or Two Depends on Your Point of View

PubMed Central

Gross, James J.; Barrett, Lisa Feldman

2010-01-01

Emotion regulation has the odd distinction of being a wildly popular construct whose scientific existence is in considerable doubt. In this article, we discuss the confusion about whether emotion generation and emotion regulation can and should be distinguished from one another. We describe a continuum of perspectives on emotion, and highlight how different (often mutually incompatible) perspectives on emotion lead to different views about whether emotion generation and emotion regulation can be usefully distinguished. We argue that making differences in perspective explicit serves the function of allowing researchers with different theoretical commitments to collaborate productively despite seemingly insurmountable differences in terminology and methods. PMID:21479078

The role of rewards in motivating participation in simple warfare.

PubMed

Glowacki, Luke; Wrangham, Richard W

2013-12-01

In the absence of explicit punitive sanctions, why do individuals voluntarily participate in intergroup warfare when doing so incurs a mortality risk? Here we consider the motivation of individuals for participating in warfare. We hypothesize that in addition to other considerations, individuals are incentivized by the possibility of rewards. We test a prediction of this "cultural rewards war-risk hypothesis" with ethnographic literature on warfare in small-scale societies. We find that a greater number of benefits from warfare is associated with a higher rate of death from conflict. This provides preliminary support for the relationship between rewards and participation in warfare.

General statistical considerations

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

Eberhardt, L L; Gilbert, R O

From NAEG plutonium environmental studies program meeting; Las Vegas, Nevada, USA (2 Oct 1973). The high sampling variability encountered in environmental plutonium studies along with high analytical costs makes it very important that efficient soil sampling plans be used. However, efficient sampling depends on explicit and simple statements of the objectives of the study. When there are multiple objectives it may be difficult to devise a wholly suitable sampling scheme. Sampling for long-term changes in plutonium concentration in soils may also be complex and expensive. Further attention to problems associated with compositing samples is recommended, as is the consistent usemore » of random sampling as a basic technique. (auth)« less

Solving time-dependent two-dimensional eddy current problems

NASA Technical Reports Server (NTRS)

Lee, Min Eig; Hariharan, S. I.; Ida, Nathan

1988-01-01

Results of transient eddy current calculations are reported. For simplicity, a two-dimensional transverse magnetic field which is incident on an infinitely long conductor is considered. The conductor is assumed to be a good but not perfect conductor. The resulting problem is an interface initial boundary value problem with the boundary of the conductor being the interface. A finite difference method is used to march the solution explicitly in time. The method is shown. Treatment of appropriate radiation conditions is given special consideration. Results are validated with approximate analytic solutions. Two stringent test cases of high and low frequency incident waves are considered to validate the results.

Law & psychiatry: mental retardation and the death penalty: after Atkins.

PubMed

Appelbaum, Paul S

2009-10-01

In Atkins v. Virginia the U.S. Supreme Court declared execution of persons with mental retardation to constitute cruel and unusual punishment, and thus to be unconstitutional under the Eighth Amendment. However, the Court left all considerations regarding how to implement the decision explicitly to the states. Since Atkins was decided in 2002, legislatures, courts, and mental health experts have struggled with its implementation, highlighting the complexities that can arise when the courts base legal rules on clinical findings. This column reviews the Atkins case and considers the challenges associated with a clinical determination that can have life-or-death consequences for capital defendants.

Implicit aversive memory under anaesthesia in animal models: a narrative review.

PubMed

Samuel, N; Taub, A H; Paz, R; Raz, A

2018-07-01

Explicit memory after anaesthesia has gained considerable attention because of its negative implications, while implicit memory, which is more elusive and lacks patients' explicit recall, has received less attention and dedicated research. This is despite the likely impact of implicit memory on postoperative long-term well-being and behaviour. Given the scarcity of human data, fear conditioning in animals offers a reliable model of implicit learning, and importantly, one where we already have a good understanding of the underlying neural circuitry in awake conditions. Animal studies provide evidence that fear conditioning occurs under anaesthesia. The effects of different anaesthetics on memory are complex, with different drugs interacting at different stages of learning. Modulatory suppressive effects can be because of context, specific drugs, and dose dependency. In some cases, low doses of general anaesthetics can actually lead to a paradoxical opposite effect. The underlying mechanisms involve several neurotransmitter systems, acting mainly in the amygdala, hippocampus, and neocortex. Here, we review animal studies of aversive conditioning under anaesthesia, discuss the complex picture that arises, identify the gaps in knowledge that require further investigation, and highlight the potential translational relevance of the models. Copyright © 2018 British Journal of Anaesthesia. Published by Elsevier Ltd. All rights reserved.

A Paradigm to Assess Implicit Attitudes towards God: The Positive/Negative God Associations Task.

PubMed

Pirutinsky, Steven; Carp, Sean; Rosmarin, David H

2017-02-01

Psychological research on the relationship between spirituality/religion and mental health has grown considerably over the past several decades and now constitutes a sizable body of scholarship. Among dimensions of S/R, positive beliefs about God have been significantly related to better mental health outcomes, and conversely negative beliefs about God are generally associated with more distress. However, prior research on this topic has relied heavily upon self-report Likert-type scales, which are vulnerable to self-report biases and measure only explicit cognitive processes. In this study, we developed and validated an implicit social cognition task, the Positive/Negative God Go/No-go Association Task (PNG-GNAT), for use in psychological research on spirituality and religion (S/R). Preliminary evidence in a large sample (N = 381) suggests that the PNG-GNAT demonstrates internal consistency, test-retest and split-half reliability, and concurrent evidence of validity. Further, our results suggest that PNG-GNAT scores represent different underlying dimensions of S/R than explicit self-report measures, and incrementally predict mental health above and beyond self-report assessment. The PNG-GNAT appears to be an effective tool for measuring implicit positive/negative beliefs about God.

Social Organization, Population, and Land Use*

PubMed Central

Axinn, William G.; Ghimire, Dirgha J.

2011-01-01

We present a new approach to the investigation of human influences on environmental change that explicitly adds consideration of social organization. This approach identifies social organization as an influence on the environment that is independent of population size, affluence, and technology. The framework we present also identifies population events, such as births, that are likely to influence environmental outcomes beyond the consequences of population size. The theoretical framework we construct explains that explicit attention to social organization is necessary for micro-level investigation of the population-environment relationship because social organization influences both. We use newly available longitudinal, multilevel, mixed-method measures of local land use changes, local population dynamics, and social organization from the Nepalese Himalayas to provide empirical tests of this new framework. These tests reveal that measures of change in social organization are strongly associated with measures of change in land use, and that the association is independent of common measures of population size, affluence, and technology. Also, local birth events shape local land use changes and key proximate determinants of land use change. Together the empirical results demonstrate key new scientific opportunities arising from the approach we present. PMID:21876607

AST: Activity-Security-Trust driven modeling of time varying networks.

PubMed

Wang, Jian; Xu, Jiake; Liu, Yanheng; Deng, Weiwen

2016-02-18

Network modeling is a flexible mathematical structure that enables to identify statistical regularities and structural principles hidden in complex systems. The majority of recent driving forces in modeling complex networks are originated from activity, in which an activity potential of a time invariant function is introduced to identify agents' interactions and to construct an activity-driven model. However, the new-emerging network evolutions are already deeply coupled with not only the explicit factors (e.g. activity) but also the implicit considerations (e.g. security and trust), so more intrinsic driving forces behind should be integrated into the modeling of time varying networks. The agents undoubtedly seek to build a time-dependent trade-off among activity, security, and trust in generating a new connection to another. Thus, we reasonably propose the Activity-Security-Trust (AST) driven model through synthetically considering the explicit and implicit driving forces (e.g. activity, security, and trust) underlying the decision process. AST-driven model facilitates to more accurately capture highly dynamical network behaviors and figure out the complex evolution process, allowing a profound understanding of the effects of security and trust in driving network evolution, and improving the biases induced by only involving activity representations in analyzing the dynamical processes.

A multi-dimensional, energy- and charge-conserving, nonlinearly implicit, electromagnetic Vlasov–Darwin particle-in-cell algorithm

DOE PAGES

Chen, G.; Chacón, L.

2015-08-11

For decades, the Vlasov–Darwin model has been recognized to be attractive for particle-in-cell (PIC) kinetic plasma simulations in non-radiative electromagnetic regimes, to avoid radiative noise issues and gain computational efficiency. However, the Darwin model results in an elliptic set of field equations that renders conventional explicit time integration unconditionally unstable. We explore a fully implicit PIC algorithm for the Vlasov–Darwin model in multiple dimensions, which overcomes many difficulties of traditional semi-implicit Darwin PIC algorithms. The finite-difference scheme for Darwin field equations and particle equations of motion is space–time-centered, employing particle sub-cycling and orbit-averaging. This algorithm conserves total energy, local charge,more » canonical-momentum in the ignorable direction, and preserves the Coulomb gauge exactly. An asymptotically well-posed fluid preconditioner allows efficient use of large cell sizes, which are determined by accuracy considerations, not stability, and can be orders of magnitude larger than required in a standard explicit electromagnetic PIC simulation. Finally, we demonstrate the accuracy and efficiency properties of the algorithm with various numerical experiments in 2D–3V.« less

'I don't view myself as a woman politician, I view myself as a politician who's a woman': The discursive management of gender identity in political leadership.

PubMed

Sorrentino, Jasmin; Augoustinos, Martha

2016-09-01

Former Prime Minister Julia Gillard's speech in the Australian parliament on sexism and misogyny received considerable public attention and controversy. However, less attention has been paid to how Gillard attended and oriented to issues related to her status as a woman during the period between her elevation to the position of Prime Minister in June 2010 and the delivery of the misogyny speech in October 2012. Using a discursive psychological approach, this article examines a corpus of interview transcripts in which gender was occasioned both explicitly and implicitly by speakers, thus requiring Gillard to attend to her gender identity. The analysis demonstrates that far from making gender a salient and relevant membership category, Gillard worked strategically to mitigate her gender as merely inconsequential to her role as Prime Minister. These findings are discussed in relation to existing research examining how gender is oriented to, negotiated, and resisted in talk to accomplish social actions, and more specifically what may be at stake for women in leadership positions who explicitly orient to gender as an identity category. © 2016 The British Psychological Society.

Robust fault-tolerant tracking control design for spacecraft under control input saturation.

PubMed

Bustan, Danyal; Pariz, Naser; Sani, Seyyed Kamal Hosseini

2014-07-01

In this paper, a continuous globally stable tracking control algorithm is proposed for a spacecraft in the presence of unknown actuator failure, control input saturation, uncertainty in inertial matrix and external disturbances. The design method is based on variable structure control and has the following properties: (1) fast and accurate response in the presence of bounded disturbances; (2) robust to the partial loss of actuator effectiveness; (3) explicit consideration of control input saturation; and (4) robust to uncertainty in inertial matrix. In contrast to traditional fault-tolerant control methods, the proposed controller does not require knowledge of the actuator faults and is implemented without explicit fault detection and isolation processes. In the proposed controller a single parameter is adjusted dynamically in such a way that it is possible to prove that both attitude and angular velocity errors will tend to zero asymptotically. The stability proof is based on a Lyapunov analysis and the properties of the singularity free quaternion representation of spacecraft dynamics. Results of numerical simulations state that the proposed controller is successful in achieving high attitude performance in the presence of external disturbances, actuator failures, and control input saturation. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

Parameterized source term in the diffusion approximation for enhanced near-field modeling of collimated light

NASA Astrophysics Data System (ADS)

Jia, Mengyu; Wang, Shuang; Chen, Xueying; Gao, Feng; Zhao, Huijuan

2016-03-01

Most analytical methods for describing light propagation in turbid medium exhibit low effectiveness in the near-field of a collimated source. Motivated by the Charge Simulation Method in electromagnetic theory as well as the established discrete source based modeling, we have reported on an improved explicit model, referred to as "Virtual Source" (VS) diffuse approximation (DA), to inherit the mathematical simplicity of the DA while considerably extend its validity in modeling the near-field photon migration in low-albedo medium. In this model, the collimated light in the standard DA is analogously approximated as multiple isotropic point sources (VS) distributed along the incident direction. For performance enhancement, a fitting procedure between the calculated and realistic reflectances is adopted in the nearfield to optimize the VS parameters (intensities and locations). To be practically applicable, an explicit 2VS-DA model is established based on close-form derivations of the VS parameters for the typical ranges of the optical parameters. The proposed VS-DA model is validated by comparing with the Monte Carlo simulations, and further introduced in the image reconstruction of the Laminar Optical Tomography system.

Physiological considerations acting on triplet oxygen for explicit dosimetry in photodynamic therapy.

PubMed

Sánchez, Víctor; Romero, María Paulina; Pratavieira, Sebastião; Costa, César

2017-09-01

The aims of this study were to determine the spatial and temporal theoretical distribution of the concentrations of Protoporphyrin IX, 3 O 2 and doses of 1 O 2 . The type II mechanism and explicit dosimetry in photodynamic therapy were used. Furthermore, the mechanism of respiration and cellular metabolism acting on 3 O 2 were taken into account. The dermis was considered as an absorbing and a scattering medium. An analytical solution was used for light diffusion in the skin. The photophysical, photochemical and biological effects caused by PDT with the initial irradiances of 20, 60 and 150mW/cm 2 were studied for a time of exposure of 20min and a maximum depth of 0.5cm. We found that the initial irradiance triples its value in 0.02cm and that almost 100% of PpIX is part of the dynamics of reactions in photodynamic therapy. Additionally, with about 40μMof 3 O 2 there is a balance between the consumed and supplied oxygen. Finally, we determined that with 60mW/cm 2 , the highest dose of 1 O 2 is obtained. Copyright © 2017 Elsevier B.V. All rights reserved.

A statistical metadata model for clinical trials' data management.

PubMed

Vardaki, Maria; Papageorgiou, Haralambos; Pentaris, Fragkiskos

2009-08-01

We introduce a statistical, process-oriented metadata model to describe the process of medical research data collection, management, results analysis and dissemination. Our approach explicitly provides a structure for pieces of information used in Clinical Study Data Management Systems, enabling a more active role for any associated metadata. Using the object-oriented paradigm, we describe the classes of our model that participate during the design of a clinical trial and the subsequent collection and management of the relevant data. The advantage of our approach is that we focus on presenting the structural inter-relation of these classes when used during datasets manipulation by proposing certain transformations that model the simultaneous processing of both data and metadata. Our solution reduces the possibility of human errors and allows for the tracking of all changes made during datasets lifecycle. The explicit modeling of processing steps improves data quality and assists in the problem of handling data collected in different clinical trials. The case study illustrates the applicability of the proposed framework demonstrating conceptually the simultaneous handling of datasets collected during two randomized clinical studies. Finally, we provide the main considerations for implementing the proposed framework into a modern Metadata-enabled Information System.

Integrating spatially explicit representations of landscape perceptions into land change research

USGS Publications Warehouse

Dorning, Monica; Van Berkel, Derek B.; Semmens, Darius J.

2017-01-01

Purpose of ReviewHuman perceptions of the landscape can influence land-use and land-management decisions. Recognizing the diversity of landscape perceptions across space and time is essential to understanding land change processes and emergent landscape patterns. We summarize the role of landscape perceptions in the land change process, demonstrate advances in quantifying and mapping landscape perceptions, and describe how these spatially explicit techniques have and may benefit land change research.Recent FindingsMapping landscape perceptions is becoming increasingly common, particularly in research focused on quantifying ecosystem services provision. Spatial representations of landscape perceptions, often measured in terms of landscape values and functions, provide an avenue for matching social and environmental data in land change studies. Integrating these data can provide new insights into land change processes, contribute to landscape planning strategies, and guide the design and implementation of land change models.SummaryChallenges remain in creating spatial representations of human perceptions. Maps must be accompanied by descriptions of whose perceptions are being represented and the validity and uncertainty of those representations across space. With these considerations, rapid advancements in mapping landscape perceptions hold great promise for improving representation of human dimensions in landscape ecology and land change research.

Cloud Condensation Nuclei Prediction Error from Application of Kohler Theory: Importance for the Aerosol Indirect Effect

NASA Technical Reports Server (NTRS)

Sotiropoulou, Rafaella-Eleni P.; Nenes, Athanasios; Adams, Peter J.; Seinfeld, John H.

2007-01-01

In situ observations of aerosol and cloud condensation nuclei (CCN) and the GISS GCM Model II' with an online aerosol simulation and explicit aerosol-cloud interactions are used to quantify the uncertainty in radiative forcing and autoconversion rate from application of Kohler theory. Simulations suggest that application of Koehler theory introduces a 10-20% uncertainty in global average indirect forcing and 2-11% uncertainty in autoconversion. Regionally, the uncertainty in indirect forcing ranges between 10-20%, and 5-50% for autoconversion. These results are insensitive to the range of updraft velocity and water vapor uptake coefficient considered. This study suggests that Koehler theory (as implemented in climate models) is not a significant source of uncertainty for aerosol indirect forcing but can be substantial for assessments of aerosol effects on the hydrological cycle in climatically sensitive regions of the globe. This implies that improvements in the representation of GCM subgrid processes and aerosol size distribution will mostly benefit indirect forcing assessments. Predictions of autoconversion, by nature, will be subject to considerable uncertainty; its reduction may require explicit representation of size-resolved aerosol composition and mixing state.

Locally adaptive, spatially explicit projection of US population for 2030 and 2050.

PubMed

McKee, Jacob J; Rose, Amy N; Bright, Edward A; Huynh, Timmy; Bhaduri, Budhendra L

2015-02-03

Localized adverse events, including natural hazards, epidemiological events, and human conflict, underscore the criticality of quantifying and mapping current population. Building on the spatial interpolation technique previously developed for high-resolution population distribution data (LandScan Global and LandScan USA), we have constructed an empirically informed spatial distribution of projected population of the contiguous United States for 2030 and 2050, depicting one of many possible population futures. Whereas most current large-scale, spatially explicit population projections typically rely on a population gravity model to determine areas of future growth, our projection model departs from these by accounting for multiple components that affect population distribution. Modeled variables, which included land cover, slope, distances to larger cities, and a moving average of current population, were locally adaptive and geographically varying. The resulting weighted surface was used to determine which areas had the greatest likelihood for future population change. Population projections of county level numbers were developed using a modified version of the US Census's projection methodology, with the US Census's official projection as the benchmark. Applications of our model include incorporating multiple various scenario-driven events to produce a range of spatially explicit population futures for suitability modeling, service area planning for governmental agencies, consequence assessment, mitigation planning and implementation, and assessment of spatially vulnerable populations.

The Full Scope of Family Physicians' Work Is Not Reflected by Current Procedural Terminology Codes.

PubMed

Young, Richard A; Burge, Sandy; Kumar, Kaparaboyna Ashok; Wilson, Jocelyn

2017-01-01

The purpose of this study was to characterize the content of family physician (FP) clinic encounters, and to count the number of visits in which the FPs addressed issues not explicitly reportable by 99211 to 99215 and 99354 Current Procedural Terminology (CPT) codes with current reimbursement methods and based on examples provided in the CPT manual. The data collection instrument was modeled on the National Ambulatory Medical Care Survey. Trained assistants directly observed every other FP-patient encounter and recorded every patient concern, issue addressed by the physician (including care barriers related to health care systems and social determinants), and treatment ordered in clinics affiliated with 10 residencies of the Residency Research Network of Texas. A visit was deemed to include physician work that was not explicitly reportable if the number or nature of issues addressed exceeded the definitions or examples for 99205/99215 or 99214 + 99354 or a preventive service code, included the physician addressing health care system or social determinant issues, or included the care of a family member. In 982 physician-patient encounters, patients raised 517 different reasons for visit (total, 5278; mean, 5.4 per visit; range, 1 to 16) and the FPs addressed 509 different issues (total issues, 3587; mean, 3.7 per visit; range, 1 to 10). FPs managed 425 different medications, 18 supplements, and 11 devices. A mean of 3.9 chronic medications were continued per visit (range, 0 to 21) and 4.6 total medications were managed (range, 0 to 22). In 592 (60.3%) of the visits the FPs did work that was not explicitly reportable with available CPT codes: 582 (59.3%) addressed more numerous issues than explicitly reportable, 64 (6.5%) addressed system barriers, and 13 (1.3%) addressed concerns for other family members. FPs perform cognitive work in a majority of their patient encounters that are not explicitly reportable, either by being higher than the CPT example number of diagnoses per code or the type of problems addressed, which has implications for the care of complex multi-morbid patients and the growth of the primary care workforce. To address these limitations, either the CPT codes and their associated rules should be updated to reflect the realities of family physicians' practices or new billing and coding approaches should be developed. © Copyright 2017 by the American Board of Family Medicine.