Sample records for models theoretical overview

  1. Introduction to Theoretical Modelling

    NASA Astrophysics Data System (ADS)

    Davis, Matthew J.; Gardiner, Simon A.; Hanna, Thomas M.; Nygaard, Nicolai; Proukakis, Nick P.; Szymańska, Marzena H.

    2013-02-01

    We briefly overview commonly encountered theoretical notions arising in the modelling of quantum gases, intended to provide a unified background to the `language' and diverse theoretical models presented elsewhere in this book, and aimed particularly at researchers from outside the quantum gases community.

  2. Advances in heat conduction models and approaches for the prediction of lattice thermal conductivity of dielectric materials

    NASA Astrophysics Data System (ADS)

    Saikia, Banashree

    2017-03-01

    An overview of predominant theoretical models used for predicting the thermal conductivities of dielectric materials is given. The criteria used for different theoretical models are explained. This overview highlights a unified theory based on temperature-dependent thermal-conductivity theories, and a drifting of the equilibrium phonon distribution function due to normal three-phonon scattering processes causes transfer of phonon momentum to (a) the same phonon modes (KK-S model) and (b) across the phonon modes (KK-H model). Estimates of the lattice thermal conductivities of LiF and Mg2Sn for the KK-H model are presented graphically.

  3. The Role of Trait Emotional Intelligence in Academic Performance: Theoretical Overview and Empirical Update.

    PubMed

    Perera, Harsha N

    2016-01-01

    Considerable debate still exists among scholars over the role of trait emotional intelligence (TEI) in academic performance. The dominant theoretical position is that TEI should be orthogonal or only weakly related to achievement; yet, there are strong theoretical reasons to believe that TEI plays a key role in performance. The purpose of the current article is to provide (a) an overview of the possible theoretical mechanisms linking TEI with achievement and (b) an update on empirical research examining this relationship. To elucidate these theoretical mechanisms, the overview draws on multiple theories of emotion and regulation, including TEI theory, social-functional accounts of emotion, and expectancy-value and psychobiological model of emotion and regulation. Although these theoretical accounts variously emphasize different variables as focal constructs, when taken together, they provide a comprehensive picture of the possible mechanisms linking TEI with achievement. In this regard, the article redresses the problem of vaguely specified theoretical links currently hampering progress in the field. The article closes with a consideration of directions for future research.

  4. Dielectronic Recombination: An Overview of Theory and Experiment, and some Astrophysical Implications

    NASA Technical Reports Server (NTRS)

    Savin, D. W.

    2000-01-01

    The status of dielectronic recombination (DR) rate coefficients used for modeling cosmic plasmas is discussed. A brief overview of theoretical and experimental studies of DR is given. Results are shown which demonstrate the astrophysical importance of accurate DR rates for studies of the intergalactic medium.

  5. The Role of Problem Construction in Creative Production

    ERIC Educational Resources Information Center

    Reiter-Palmon, Roni

    2017-01-01

    This paper provides an overview of theory and research regarding problem construction and identification. Specifically, the paper reviews a theoretical model of processes associated with problem construction and empirical evidence in relation to the model. Finally, the paper reviews the literature on team problem construction.

  6. Quantum Mechanics, Path Integrals and Option Pricing:. Reducing the Complexity of Finance

    NASA Astrophysics Data System (ADS)

    Baaquie, Belal E.; Corianò, Claudio; Srikant, Marakani

    2003-04-01

    Quantum Finance represents the synthesis of the techniques of quantum theory (quantum mechanics and quantum field theory) to theoretical and applied finance. After a brief overview of the connection between these fields, we illustrate some of the methods of lattice simulations of path integrals for the pricing of options. The ideas are sketched out for simple models, such as the Black-Scholes model, where analytical and numerical results are compared. Application of the method to nonlinear systems is also briefly overviewed. More general models, for exotic or path-dependent options are discussed.

  7. The Role of Creativity in Models of Resilience: Theoretical Exploration and Practical Applications

    ERIC Educational Resources Information Center

    Metzl, Einat S.; Morrell, Malissa A.

    2008-01-01

    This exploration reviews current conceptualizations of resilience and creativity, suggesting important links between these two concepts, and offers a modified model for future research and applied clinical interventions. First, the authors examine four main models of resilience. Then, an overview of definitions and characteristics of creativity is…

  8. Models of Sexual and Relational Orientation: A Critical Review and Synthesis

    ERIC Educational Resources Information Center

    Moe, Jeffry L.; Reicherzer, Stacee; Dupuy, Paula J.

    2011-01-01

    Many frameworks exist to explain and describe the phenomenon of same-sex sexuality as it applies to human development. This conceptual article provides a critical overview and synthesis of previous models to serve as a theoretical bridge for the suggested multiple continua model of sexual and relational orientations. Recommendations for how…

  9. Developing a theoretical framework for complex community-based interventions.

    PubMed

    Angeles, Ricardo N; Dolovich, Lisa; Kaczorowski, Janusz; Thabane, Lehana

    2014-01-01

    Applying existing theories to research, in the form of a theoretical framework, is necessary to advance knowledge from what is already known toward the next steps to be taken. This article proposes a guide on how to develop a theoretical framework for complex community-based interventions using the Cardiovascular Health Awareness Program as an example. Developing a theoretical framework starts with identifying the intervention's essential elements. Subsequent steps include the following: (a) identifying and defining the different variables (independent, dependent, mediating/intervening, moderating, and control); (b) postulating mechanisms how the independent variables will lead to the dependent variables; (c) identifying existing theoretical models supporting the theoretical framework under development; (d) scripting the theoretical framework into a figure or sets of statements as a series of hypotheses, if/then logic statements, or a visual model; (e) content and face validation of the theoretical framework; and (f) revising the theoretical framework. In our example, we combined the "diffusion of innovation theory" and the "health belief model" to develop our framework. Using the Cardiovascular Health Awareness Program as the model, we demonstrated a stepwise process of developing a theoretical framework. The challenges encountered are described, and an overview of the strategies employed to overcome these challenges is presented.

  10. Quality of Work Life: Theoretical and Methodological Problems, and Presentation of a New Model and Measuring Instrument

    ERIC Educational Resources Information Center

    Martel, Jean-Pierre; Dupuis, Gilles

    2006-01-01

    Purpose: Ever since the concept of Quality of Work Life (QWL) was first used over 30 years ago, a range of definitions and theoretical constructs have succeeded each other with the aim of mitigating the many problems facing the concept. A historical overview of the concept of QWL is presented here. Given the lack of consensus concerning the…

  11. Latest Trends in German Political Socialisation Research.

    ERIC Educational Resources Information Center

    Claussen, Bernhard

    1979-01-01

    Presents an overview of the most notable among recent books on political socialization in West Germany and indicates trends among these publications in areas of research methodology, objectives, stress on empirical studies, and theoretical models. (Author/DB)

  12. Open-Ended Learning Environments: A Theoretical Framework and Model for Design.

    ERIC Educational Resources Information Center

    Hill, Janette R.; Land, Susan M.

    This paper presents a framework and model for design of open-ended learning environments (OELEs). First, an overview is presented that addresses key characteristics of OELEs, including: use of meaningful, complex contexts; provision of tools and resources; learner reflection and self-monitoring; and social, material, or technological scaffolding.…

  13. Towards an integrated model of nursing competence: an overview of the literature reviews and concept analysis.

    PubMed

    Caruso, Roberto; Fida, Roberta; Sili, Alessandro; Arrigoni, Cristina

    2016-01-01

    Competence is considered a fundamental element when measuring a nurse's or student's ability to provide nursing care, but there is no consensus on what competence really is. This paper aims to review the existing meanings and models of nursing competence. The overview of literature reviews and concept analysis was performed through a search on Pubmed, Cinahl and PsychINFO from January 2005 to September 2014. It included key words, such as: Competence Model; Professional Competence; Nursing Competence; Competency Model; Professional Competency; Nursing Competency. A total of 14 papers were found, coming from educational or clinical nursing field. It was possible to identify some common themes: description of competence determinants; confu- sion around the competence concept; lack in competence evaluation; lack when competence have to be operationalized. The overview results, enriched by the literature coming out from the organiza- tional studies, build the conceptual basis of an integrated model of nursing competence. More empirical research is needed to test the theoretical assumptions.

  14. A practitioner's guide to persuasion: an overview of 15 selected persuasion theories, models and frameworks.

    PubMed

    Cameron, Kenzie A

    2009-03-01

    To provide a brief overview of 15 selected persuasion theories and models, and to present examples of their use in health communication research. The theories are categorized as message effects models, attitude-behavior approaches, cognitive processing theories and models, consistency theories, inoculation theory, and functional approaches. As it is often the intent of a practitioner to shape, reinforce, or change a patient's behavior, familiarity with theories of persuasion may lead to the development of novel communication approaches with existing patients. This article serves as an introductory primer to theories of persuasion with applications to health communication research. Understanding key constructs and general formulations of persuasive theories may allow practitioners to employ useful theoretical frameworks when interacting with patients.

  15. An overview of structural equation modeling: its beginnings, historical development, usefulness and controversies in the social sciences.

    PubMed

    Tarka, Piotr

    2018-01-01

    This paper is a tribute to researchers who have significantly contributed to improving and advancing structural equation modeling (SEM). It is, therefore, a brief overview of SEM and presents its beginnings, historical development, its usefulness in the social sciences and the statistical and philosophical (theoretical) controversies which have often appeared in the literature pertaining to SEM. Having described the essence of SEM in the context of causal analysis, the author discusses the years of the development of structural modeling as the consequence of many researchers' systematically growing needs (in particular in the social sciences) who strove to effectively understand the structure and interactions of latent phenomena. The early beginnings of SEM models were related to the work of Spearman and Wright, and to that of other prominent researchers who contributed to SEM development. The importance and predominance of theoretical assumptions over technical issues for the successful construction of SEM models are also described. Then, controversies regarding the use of SEM in the social sciences are presented. Finally, the opportunities and threats of this type of analytical strategy as well as selected areas of SEM applications in the social sciences are discussed.

  16. Wife Abuse and the Wife Abuser: Review and Recommendations.

    ERIC Educational Resources Information Center

    Carden, Ann D.

    1994-01-01

    Reviews clinical, theoretical, and empirical literature on wife abuse/abusers. Presents historical and contextual information, overview of domestic violence, prevalence data, and descriptions of evolution and current status of public and professional awareness and response. Proposes integrative model for understanding etiologic, dynamic, and…

  17. Theoretical Models and Operational Frameworks in Public Health Ethics

    PubMed Central

    Petrini, Carlo

    2010-01-01

    The article is divided into three sections: (i) an overview of the main ethical models in public health (theoretical foundations); (ii) a summary of several published frameworks for public health ethics (practical frameworks); and (iii) a few general remarks. Rather than maintaining the superiority of one position over the others, the main aim of the article is to summarize the basic approaches proposed thus far concerning the development of public health ethics by describing and comparing the various ideas in the literature. With this in mind, an extensive list of references is provided. PMID:20195441

  18. Computational models of neuromodulation.

    PubMed

    Fellous, J M; Linster, C

    1998-05-15

    Computational modeling of neural substrates provides an excellent theoretical framework for the understanding of the computational roles of neuromodulation. In this review, we illustrate, with a large number of modeling studies, the specific computations performed by neuromodulation in the context of various neural models of invertebrate and vertebrate preparations. We base our characterization of neuromodulations on their computational and functional roles rather than on anatomical or chemical criteria. We review the main framework in which neuromodulation has been studied theoretically (central pattern generation and oscillations, sensory processing, memory and information integration). Finally, we present a detailed mathematical overview of how neuromodulation has been implemented at the single cell and network levels in modeling studies. Overall, neuromodulation is found to increase and control computational complexity.

  19. Theoretical Astrophysics - Volume 3, Galaxies and Cosmology

    NASA Astrophysics Data System (ADS)

    Padmanabhan, T.

    2002-12-01

    1. Overview: galaxies and cosmology; 2. Galactic structure and dynamics; 3. Friedmann model of the universe; 4. Thermal history of the universe; 5. Structure formation; 6. Cosmic microwave background radiation; 7. Formation of baryonic structures; 8. Active galactic nuclei; 9. Intergalactic medium and absorption systems; 10. Cosmological observations.

  20. Families Helping Families: Implementing a Multifamily Therapy Group with Substance-Abusing Adolescents.

    ERIC Educational Resources Information Center

    Springer, David W.; Orsbon, Sarah H.

    2002-01-01

    In treating a substance-abusing adolescent, the family is a key target of intervention. Multifamily therapy groups (MFTGs) have been used to involve families in treatment and have been found to be effective with a variety of populations. This article provides a theoretical overview of a MFTG model and describes the implementation of the model with…

  1. Understanding Students' Motivation in Sport and Physical Education: From the Expectancy-Value Model and Self-Efficacy Theory Perspectives

    ERIC Educational Resources Information Center

    Gao, Zan; Lee, Amelia M.; Harrison, Louis, Jr.

    2008-01-01

    In this article, the roles of individuals' expectancy beliefs and incentives (i.e., task value, outcome expectancy) in sport and physical education are examined from expectancy-value model and self-efficacy theory perspectives. Overviews of the two theoretical frameworks and the conceptual and measurement issues are provided, followed by a review…

  2. Megastudies, crowdsourcing, and large datasets in psycholinguistics: An overview of recent developments.

    PubMed

    Keuleers, Emmanuel; Balota, David A

    2015-01-01

    This paper introduces and summarizes the special issue on megastudies, crowdsourcing, and large datasets in psycholinguistics. We provide a brief historical overview and show how the papers in this issue have extended the field by compiling new databases and making important theoretical contributions. In addition, we discuss several studies that use text corpora to build distributional semantic models to tackle various interesting problems in psycholinguistics. Finally, as is the case across the papers, we highlight some methodological issues that are brought forth via the analyses of such datasets.

  3. Sex Therapy: Advances in Paradigms, Nomenclature, and Treatment

    ERIC Educational Resources Information Center

    Althof, Stanley

    2010-01-01

    Objective: The author reviews the historical paradigms that have influenced the treatment of sexual problems, changes in the diagnostic nomenclature, and recent innovations in sex therapy. Methods: The author reviews the literature and provides expert opinion. Results: The author gives a historical overview of how theoretical models of…

  4. Discourse on Disability and Rehabilitation Issues: Opportunities for Psychology.

    ERIC Educational Resources Information Center

    Pledger, Constance

    2003-01-01

    Discusses the old and new paradigms of disability. Examines the relevance to psychology, summarizes the fundamental theoretical frameworks that have influenced the current state of the science in disability and rehabilitation, and offers an overview of definitions, terminology, and models of disability. Concludes with an introduction to four other…

  5. A Metatheory of Spiritual Formation through Service-Learning in Higher Education

    ERIC Educational Resources Information Center

    Welch, Marshall; Koth, Kent

    2013-01-01

    This article presents a hybrid metatheory of spiritual formation that can be applied to understanding college students' spiritual development through service-learning experiences. A definition and overview of spirituality is presented and contrasted with religion, followed by a review of various theoretical models from developmental…

  6. Inertial confinement fusion for energy: overview of the ongoing experimental, theoretical and numerical studies

    NASA Astrophysics Data System (ADS)

    Jacquemot, S.

    2017-10-01

    This paper provides an overview of the results presented at the 26th IAEA Fusion Energy Conference in the field of inertial confinement fusion for energy, covering its various experimental, numerical/theoretical and technological facets, as well as the different paths towards ignition that are currently followed worldwide.

  7. ICHEP 2014 Summary: Theory Status after the First LHC Run

    NASA Astrophysics Data System (ADS)

    Pich, Antonio

    2016-04-01

    A brief overview of the main highlights discussed at ICHEP 2014 is presented. The experimental data confirm that the scalar boson discovered at the LHC couples to other particles as predicted in the Standard Model. This constitutes a great success of the present theoretical paradigm, which has been confirmed as the correct description at the electroweak scale. At the same time, the negative searches for signals of new phenomena tightly constrain many new-physics scenarios, challenging previous theoretical wisdom and opening new perspectives in fundamental physics. Fresh ideas are needed to face the many pending questions unanswered within the Standard Model framework.

  8. The Pentagon's Military Analyst Program

    ERIC Educational Resources Information Center

    Valeri, Andy

    2014-01-01

    This article provides an investigatory overview of the Pentagon's military analyst program, what it is, how it was implemented, and how it constitutes a form of propaganda. A technical analysis of the program is applied using the theoretical framework of the propaganda model first developed by Noam Chomsky and Edward S. Herman. Definitions…

  9. Clouds and the Earth's Radiant Energy System (CERES) algorithm theoretical basis document. Volume 1; Overviews (subsystem 0)

    NASA Technical Reports Server (NTRS)

    Wielicki, Bruce A. (Principal Investigator); Barkstrom, Bruce R. (Principal Investigator); Baum, Bryan A.; Cess, Robert D.; Charlock, Thomas P.; Coakley, James A.; Green, Richard N.; Lee, Robert B., III; Minnis, Patrick; Smith, G. Louis

    1995-01-01

    The theoretical bases for the Release 1 algorithms that will be used to process satellite data for investigation of the Clouds and the Earth's Radiant Energy System (CERES) are described. The architecture for software implementation of the methodologies is outlined. Volume 1 provides both summarized and detailed overviews of the CERES Release 1 data analysis system. CERES will produce global top-of-the-atmosphere shortwave and longwave radiative fluxes at the top of the atmosphere, at the surface, and within the atmosphere by using the combination of a large variety of measurements and models. The CERES processing system includes radiance observations from CERES scanning radiometers, cloud properties derived from coincident satellite imaging radiometers, temperature and humidity fields from meteorological analysis models, and high-temporal-resolution geostationary satellite radiances to account for unobserved times. CERES will provide a continuation of the ERBE record and the lowest error climatology of consistent cloud properties and radiation fields. CERES will also substantially improve our knowledge of the Earth's surface radiation budget.

  10. A brief overview of computational structures technology related activities at NASA Lewis Research Center

    NASA Technical Reports Server (NTRS)

    Hopkins, Dale A.

    1992-01-01

    The presentation gives a partial overview of research and development underway in the Structures Division of LeRC, which collectively is referred to as the Computational Structures Technology Program. The activities in the program are diverse and encompass four major categories: (1) composite materials and structures; (2) probabilistic analysis and reliability; (3) design optimization and expert systems; and (4) computational methods and simulation. The approach of the program is comprehensive and entails exploration of fundamental theories of structural mechanics to accurately represent the complex physics governing engine structural performance, formulation, and implementation of computational techniques and integrated simulation strategies to provide accurate and efficient solutions of the governing theoretical models by exploiting the emerging advances in computer technology, and validation and verification through numerical and experimental tests to establish confidence and define the qualities and limitations of the resulting theoretical models and computational solutions. The program comprises both in-house and sponsored research activities. The remainder of the presentation provides a sample of activities to illustrate the breadth and depth of the program and to demonstrate the accomplishments and benefits that have resulted.

  11. ANSYS tools in modeling tires

    NASA Technical Reports Server (NTRS)

    Ali, Ashraf; Lovell, Michael

    1995-01-01

    This presentation summarizes the capabilities in the ANSYS program that relate to the computational modeling of tires. The power and the difficulties associated with modeling nearly incompressible rubber-like materials using hyperelastic constitutive relationships are highlighted from a developer's point of view. The topics covered include a hyperelastic material constitutive model for rubber-like materials, a general overview of contact-friction capabilities, and the acoustic fluid-structure interaction problem for noise prediction. Brief theoretical development and example problems are presented for each topic.

  12. Acoustic Modeling of Lightweight Structures: A Literature Review

    NASA Astrophysics Data System (ADS)

    Yang, Shasha; Shen, Cheng

    2017-10-01

    This paper gives an overview of acoustic modeling for three kinds of typical lightweight structures including double-leaf plate system, stiffened single (or double) plate and porous material. Classical models are citied to provide frame work of theoretical modeling for acoustic property of lightweight structures; important research advances derived by our research group and other authors are introduced to describe the current state of art for acoustic research. Finally, remaining problems and future research directions are concluded and prospected briefly

  13. Avalanches and plastic flow in crystal plasticity: an overview

    NASA Astrophysics Data System (ADS)

    Papanikolaou, Stefanos; Cui, Yinan; Ghoniem, Nasr

    2018-01-01

    Crystal plasticity is mediated through dislocations, which form knotted configurations in a complex energy landscape. Once they disentangle and move, they may also be impeded by permanent obstacles with finite energy barriers or frustrating long-range interactions. The outcome of such complexity is the emergence of dislocation avalanches as the basic mechanism of plastic flow in solids at the nanoscale. While the deformation behavior of bulk materials appears smooth, a predictive model should clearly be based upon the character of these dislocation avalanches and their associated strain bursts. We provide here a comprehensive overview of experimental observations, theoretical models and computational approaches that have been developed to unravel the multiple aspects of dislocation avalanche physics and the phenomena leading to strain bursts in crystal plasticity.

  14. Mindfulness-based treatment to prevent addictive behavior relapse: theoretical models and hypothesized mechanisms of change.

    PubMed

    Witkiewitz, Katie; Bowen, Sarah; Harrop, Erin N; Douglas, Haley; Enkema, Matthew; Sedgwick, Carly

    2014-04-01

    Mindfulness-based treatments are growing in popularity among addiction treatment providers, and several studies suggest the efficacy of incorporating mindfulness practices into the treatment of addiction, including the treatment of substance use disorders and behavioral addictions (i.e., gambling). The current paper provides a review of theoretical models of mindfulness in the treatment of addiction and several hypothesized mechanisms of change. We provide an overview of mindfulness-based relapse prevention (MBRP), including session content, treatment targets, and client feedback from participants who have received MBRP in the context of empirical studies. Future research directions regarding operationalization and measurement, identifying factors that moderate treatment effects, and protocol adaptations for specific populations are discussed.

  15. An overview of quantitative approaches in Gestalt perception.

    PubMed

    Jäkel, Frank; Singh, Manish; Wichmann, Felix A; Herzog, Michael H

    2016-09-01

    Gestalt psychology is often criticized as lacking quantitative measurements and precise mathematical models. While this is true of the early Gestalt school, today there are many quantitative approaches in Gestalt perception and the special issue of Vision Research "Quantitative Approaches in Gestalt Perception" showcases the current state-of-the-art. In this article we give an overview of these current approaches. For example, ideal observer models are one of the standard quantitative tools in vision research and there is a clear trend to try and apply this tool to Gestalt perception and thereby integrate Gestalt perception into mainstream vision research. More generally, Bayesian models, long popular in other areas of vision research, are increasingly being employed to model perceptual grouping as well. Thus, although experimental and theoretical approaches to Gestalt perception remain quite diverse, we are hopeful that these quantitative trends will pave the way for a unified theory. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Human factors in software development

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

    Curtis, B.

    1986-01-01

    This book presents an overview of ergonomics/human factors in software development, recent research, and classic papers. Articles are drawn from the following areas of psychological research on programming: cognitive ergonomics, cognitive psychology, and psycholinguistics. Topics examined include: theoretical models of how programmers solve technical problems, the characteristics of programming languages, specification formats in behavioral research and psychological aspects of fault diagnosis.

  17. Practical Implications for the Development of Applied Metaphor in Adventure Therapy

    ERIC Educational Resources Information Center

    Hartford, Gary

    2011-01-01

    This paper considers the definitions, role, and use of metaphor in adventure therapy. It provides an overview of theoretical perspectives on metaphor and the related ways in which metaphor is used in adventure therapy. Research on the use of metaphor in counselling and from neuropsychology and linguistics is applied to a model of metaphor use in…

  18. Using the Personalized System of Instruction to Differentiate Instruction in Fitness

    ERIC Educational Resources Information Center

    Viness, Stephanie; Colquitt, Gavin; Pritchard, Tony; Johnson, Christine

    2017-01-01

    The purpose of this article is to provide an overview of how PE teachers can personalize learning to meet a variety of student needs. Differentiated instruction (DI) is a term frequently used in classroom-based learning to describe a method of personalization for individual students. The term can also describe a theoretical model for teaching and…

  19. Implementing the Zone of Proximal Development: From the Pedagogical Experiment to the Developmental Education System of Leonid Zankov

    ERIC Educational Resources Information Center

    Guseva, Liudmila G.; Solomonovich, Mark

    2017-01-01

    This article overviews the theoretical and applied works of the psychologist and pedagogue Leonid Zankov. Zankov's model of teaching is based on Vygotsky's theory that appropriate teaching methods stimulate cognitive development, whose core notion is the Zone of Proximal Development. This educational psychology research was verified by large scale…

  20. A Curriculum Development Route Map for a Technology Enhanced Learning Era

    ERIC Educational Resources Information Center

    Castañeda, Linda; Prendes, Paz

    2013-01-01

    In this paper we are trying to present a model of analysis that includes a comprehensive perspective of the state of the art in the specialized literature about curriculum development. From this theoretical approach, we get a complete curriculum overview. Including insights into: what are the curriculum principal elements, what we already know…

  1. A Comparative Study of Test Data Dimensionality Assessment Procedures Under Nonparametric IRT Models

    ERIC Educational Resources Information Center

    van Abswoude, Alexandra A. H.; van der Ark, L. Andries; Sijtsma, Klaas

    2004-01-01

    In this article, an overview of nonparametric item response theory methods for determining the dimensionality of item response data is provided. Four methods were considered: MSP, DETECT, HCA/CCPROX, and DIMTEST. First, the methods were compared theoretically. Second, a simulation study was done to compare the effectiveness of MSP, DETECT, and…

  2. Control of experimental uncertainties in filtered Rayleigh scattering measurements

    NASA Technical Reports Server (NTRS)

    Forkey, Joseph N.; Finkelstein, N. D.; Lempert, Walter R.; Miles, Richard B.

    1995-01-01

    Filtered Rayleigh Scattering is a technique which allows for measurement of velocity, temperature, and pressure in unseeded flows, spatially resolved in 2-dimensions. We present an overview of the major components of a Filtered Rayleigh Scattering system. In particular, we develop and discuss a detailed theoretical model along with associated model parameters and related uncertainties. Based on this model, we then present experimental results for ambient room air and for a Mach 2 free jet, including spatially resolved measurements of velocity, temperature, and pressure.

  3. A differential geometry model for the perceived colors space

    NASA Astrophysics Data System (ADS)

    Provenzi, Edoardo

    2016-06-01

    The space of perceived colors, before acquiring an industrial interest, has received a systematic theoretical attention from philosophers, physicists and mathematicians. The research about this topic is still active nowadays. In this paper, it will be presented a critical overview of a model based on differential geometry proposed by H. L. Resnikoff in 1974. It will be shown that, while some fundamental and elegant ideas behind this model can be still used as a guiding principle, some other parts of the model must be updated to comply with the modern findings about color perception.

  4. Photons Revisited

    NASA Astrophysics Data System (ADS)

    Batic, Matej; Begalli, Marcia; Han, Min Cheol; Hauf, Steffen; Hoff, Gabriela; Kim, Chan Hyeong; Kim, Han Sung; Grazia Pia, Maria; Saracco, Paolo; Weidenspointner, Georg

    2014-06-01

    A systematic review of methods and data for the Monte Carlo simulation of photon interactions is in progress: it concerns a wide set of theoretical modeling approaches and data libraries available for this purpose. Models and data libraries are assessed quantitatively with respect to an extensive collection of experimental measurements documented in the literature to determine their accuracy; this evaluation exploits rigorous statistical analysis methods. The computational performance of the associated modeling algorithms is evaluated as well. An overview of the assessment of photon interaction models and results of the experimental validation are presented.

  5. THEORY IN RELIGION AND AGING: AN OVERVIEW

    PubMed Central

    Levin, Jeff; Chatters, Linda M.; Taylor, Robert Joseph

    2011-01-01

    This paper provides an overview of theory in religion, aging, and health. It offers both a primer on theory and a roadmap for researchers. Four “tenses” of theory are described—distinct ways that theory comes into play in this field: grand theory, mid-range theory, use of theoretical models, and positing of constructs which mediate or moderate putative religious effects. Examples are given of both explicit and implicit uses of theory. Sources of theory for this field are then identified, emphasizing perspectives of sociologists and psychologists, and discussion is given to limitations of theory. Finally, reflections are offered as to why theory matters. PMID:20087662

  6. Career Development Models: A Brief Overview of Relevant Theory

    DTIC Science & Technology

    1989-01-01

    Gottfredson , and Vondracek, Lerner, and Schulenberg have the least such support. vii A CONTENTS Page INTRODUCTION...Theory of Dawis and Lofquist (1984) and Tiedeman and O’Hara (1963). More recent theoretical approaches of interest include that of Gottfredson (1981...by Gottfredson (1981). This theory views career development in terms of the process by which occupational aspirations are circumscribed and

  7. Marine Renewable Energy: Resource Characterization and Physical Effects

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

    Yang, Zhaoqing; Copping, Andrea E.

    This complete reference to marine renewable energy covers aspects of resource characterization and physical effects of harvesting the ocean’s vast and powerful resources—from wave and tidal stream to ocean current energy. Experts in each of these areas contribute their insights to provide a cohesive overview of the marine renewable energy spectrum based on theoretical, numerical modeling, and field-measurement approaches.

  8. Energetic particle instabilities in fusion plasmas

    NASA Astrophysics Data System (ADS)

    Sharapov, S. E.; Alper, B.; Berk, H. L.; Borba, D. N.; Breizman, B. N.; Challis, C. D.; Classen, I. G. J.; Edlund, E. M.; Eriksson, J.; Fasoli, A.; Fredrickson, E. D.; Fu, G. Y.; Garcia-Munoz, M.; Gassner, T.; Ghantous, K.; Goloborodko, V.; Gorelenkov, N. N.; Gryaznevich, M. P.; Hacquin, S.; Heidbrink, W. W.; Hellesen, C.; Kiptily, V. G.; Kramer, G. J.; Lauber, P.; Lilley, M. K.; Lisak, M.; Nabais, F.; Nazikian, R.; Nyqvist, R.; Osakabe, M.; Perez von Thun, C.; Pinches, S. D.; Podesta, M.; Porkolab, M.; Shinohara, K.; Schoepf, K.; Todo, Y.; Toi, K.; Van Zeeland, M. A.; Voitsekhovich, I.; White, R. B.; Yavorskij, V.; TG, ITPA EP; Contributors, JET-EFDA

    2013-10-01

    Remarkable progress has been made in diagnosing energetic particle instabilities on present-day machines and in establishing a theoretical framework for describing them. This overview describes the much improved diagnostics of Alfvén instabilities and modelling tools developed world-wide, and discusses progress in interpreting the observed phenomena. A multi-machine comparison is presented giving information on the performance of both diagnostics and modelling tools for different plasma conditions outlining expectations for ITER based on our present knowledge.

  9. Mindfulness-Based Treatment to Prevent Addictive Behavior Relapse: Theoretical Models and Hypothesized Mechanisms of Change

    PubMed Central

    Witkiewitz, Katie; Bowen, Sarah; Harrop, Erin N.; Douglas, Haley; Enkema, Matthew; Sedgwick, Carly

    2017-01-01

    Mindfulness-based treatments are growing in popularity among addiction treatment providers, and several studies suggest the efficacy of incorporating mindfulness practices into the treatment of addiction, including the treatment of substance use disorders and behavioral addictions (i.e., gambling). The current paper provides a review of theoretical models of mindfulness in the treatment of addiction and several hypothesized mechanisms of change. We provide an overview of mindfulness-based relapse prevention (MBRP), including session content, treatment targets, and client feedback from participants who have received MBRP in the context of empirical studies. Future research directions regarding operationalization and measurement, identifying factors that moderate treatment effects, and protocol adaptations for specific populations are discussed. PMID:24611847

  10. Equations of state for hydrogen and deuterium.

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

    Kerley, Gerald Irwin

    2003-12-01

    This report describes the complete revision of a deuterium equation of state (EOS) model published in 1972. It uses the same general approach as the 1972 EOS, i.e., the so-called 'chemical model,' but incorporates a number of theoretical advances that have taken place during the past thirty years. Three phases are included: a molecular solid, an atomic solid, and a fluid phase consisting of both molecular and atomic species. Ionization and the insulator-metal transition are also included. The most important improvements are in the liquid perturbation theory, the treatment of molecular vibrations and rotations, and the ionization equilibrium and mixturemore » models. In addition, new experimental data and theoretical calculations are used to calibrate certain model parameters, notably the zero-Kelvin isotherms for the molecular and atomic solids, and the quantum corrections to the liquid phase. The report gives a general overview of the model, followed by detailed discussions of the most important theoretical issues and extensive comparisons with the many experimental data that have been obtained during the last thirty years. Questions about the validity of the chemical model are also considered. Implications for modeling the 'giant planets' are also discussed.« less

  11. Reverse-Engineering Laboratory Astrophysics: Oxygen Inner-shell Absorption in the ISM

    NASA Technical Reports Server (NTRS)

    Garcia, J.; Gatuzz, E.; Kallman, T. R.; Mendoza, C.; Gorczyca, T. W.

    2017-01-01

    The modeling of X-ray spectra from photoionized astrophysical plasmas has been significantly improved due to recent advancements in the theoretical and numerical frameworks, as well as a consolidated and reliable atomic database of inner-shell transitions for all the relevant ions. We discuss these developments and the current state of X-ray spectral modeling in the context of oxygen cold absorption in the interstellar medium (ISM). Unconventionally, we use high-resolution astrophysical observations to accurately determine line positions, and adjust the theoretical models for a comprehensive interpretation of the observed X-ray spectra. This approach has brought to light standing discrepancies in the neutral oxygen absorption-line positions determined from observations and laboratory measurements. We give an overview of our current efforts to devise a definitive model of oxygen photoabsorption that can help to resolve the existing controversy regarding ISM atomic and molecular fractions.

  12. Reverse-engineering laboratory astrophysics: Oxygen inner-shell absorption in the ISM

    NASA Astrophysics Data System (ADS)

    García, J.; Gatuzz, E.; Kallman, T. R.; Mendoza, C.; Gorczyca, T. W.

    2017-03-01

    The modeling of X-ray spectra from photoionized astrophysical plasmas has been significantly improved due to recent advancements in the theoretical and numerical frameworks, as well as a consolidated and reliable atomic database of inner-shell transitions for all the relevant ions. We discuss these developments and the current state of X-ray spectral modeling in the context of oxygen cold absorption in the interstellar medium (ISM). Unconventionally, we use high-resolution astrophysical observations to accurately determine line positions, and adjust the theoretical models for a comprehensive interpretation of the observed X-ray spectra. This approach has brought to light standing discrepancies in the neutral oxygen absorption-line positions determined from observations and laboratory measurements. We give an overview of our current efforts to devise a definitive model of oxygen photoabsorption that can help to resolve the existing controversy regarding ISM atomic and molecular fractions.

  13. Cost-benefit study of consumer product take-back programs using IBM's WIT reverse logistics optimization tool

    NASA Astrophysics Data System (ADS)

    Veerakamolmal, Pitipong; Lee, Yung-Joon; Fasano, J. P.; Hale, Rhea; Jacques, Mary

    2002-02-01

    In recent years, there has been increased focus by regulators, manufacturers, and consumers on the issue of product end of life management for electronics. This paper presents an overview of a conceptual study designed to examine the costs and benefits of several different Product Take Back (PTB) scenarios for used electronics equipment. The study utilized a reverse logistics supply chain model to examine the effects of several different factors in PTB programs. The model was done using the IBM supply chain optimization tool known as WIT (Watson Implosion Technology). Using the WIT tool, we were able to determine a theoretical optimal cost scenario for PTB programs. The study was designed to assist IBM internally in determining theoretical optimal Product Take Back program models and determining potential incentives for increasing participation rates.

  14. The role of learning-related dopamine signals in addiction vulnerability.

    PubMed

    Huys, Quentin J M; Tobler, Philippe N; Hasler, Gregor; Flagel, Shelly B

    2014-01-01

    Dopaminergic signals play a mathematically precise role in reward-related learning, and variations in dopaminergic signaling have been implicated in vulnerability to addiction. Here, we provide a detailed overview of the relationship between theoretical, mathematical, and experimental accounts of phasic dopamine signaling, with implications for the role of learning-related dopamine signaling in addiction and related disorders. We describe the theoretical and behavioral characteristics of model-free learning based on errors in the prediction of reward, including step-by-step explanations of the underlying equations. We then use recent insights from an animal model that highlights individual variation in learning during a Pavlovian conditioning paradigm to describe overlapping aspects of incentive salience attribution and model-free learning. We argue that this provides a computationally coherent account of some features of addiction. © 2014 Elsevier B.V. All rights reserved.

  15. Women’s Sexuality: Behaviors, Responses, and Individual Differences

    PubMed Central

    Andersen, Barbara L.; Cyranowski, Jill M.

    2009-01-01

    Classic and contemporary approaches to the assessment of female sexuality are discussed. General approaches, assessment strategies, and models of female sexuality are organized within the conceptual domains of sexual behaviors, sexual responses (desire, excitement, orgasm, and resolution), and individual differences, including general and sex-specific personality models. Where applicable, important trends and relationships are highlighted in the literature with both existing reports and previously unpublished data. The present conceptual overview highlights areas in sexual assessment and model building that are in need of further research and theoretical clarification. PMID:8543712

  16. North Carolina’s Response to the Directorate of Health Care Studies and Clinical Investigation’s Final Report: Assessing Power Analysis Approaches for the Fort Bragg Evaluation Project

    DTIC Science & Technology

    1993-08-31

    American Society of Criminology, Denver , Colorado , November, 1983. (50) ’Unemployment and Crime Rates in Post-World War 11 United States: A Theoretical and... Denver , Colorado , August 20-September 2, 1971 (2) "Social Indicator Models," American Sociological Association Annual Meeting, San Francisco...Association, Denver , Colorado , August, 1971. (10) ’Social Indicator Models: An Overview." Paper presented at the annual meetings of the American

  17. Computational intelligence in earth sciences and environmental applications: issues and challenges.

    PubMed

    Cherkassky, V; Krasnopolsky, V; Solomatine, D P; Valdes, J

    2006-03-01

    This paper introduces a generic theoretical framework for predictive learning, and relates it to data-driven and learning applications in earth and environmental sciences. The issues of data quality, selection of the error function, incorporation of the predictive learning methods into the existing modeling frameworks, expert knowledge, model uncertainty, and other application-domain specific problems are discussed. A brief overview of the papers in the Special Issue is provided, followed by discussion of open issues and directions for future research.

  18. Psychological models of suicide.

    PubMed

    Barzilay, Shira; Apter, Alan

    2014-01-01

    Suicidal behavior is highly complex and multifaceted. Consequent to the pioneering work of Durkheim and Freud, theoreticians have attempted to explain the biological, social, and psychological nature of suicide. The present work presents an overview and critical discussion of the most influential theoretical models of the psychological mechanisms underlying the development of suicidal behavior. All have been tested to varying degrees and have important implications for the development of therapeutic and preventive interventions. Broader and more in-depth approaches are still needed to further our understanding of suicidal phenomena.

  19. Understanding Bilingual Education: An Overview of Key Notions in the Literature and the Implications for Chinese University EFL Education

    ERIC Educational Resources Information Center

    Ping, Wang

    2017-01-01

    This article starts with a review of definitions of bilingualism. It then discusses the definition of bilingual education with its focus on the analysis of bilingual competence. It is subsequently suggested that a theoretical hard nut to be cracked in today's bilingual research is to establish the scope of discussion of bilingualism models meeting…

  20. Person-centered nursing practice with older people in Ireland.

    PubMed

    Landers, Margaret G; McCarthy, Geraldine M

    2007-01-01

    This column presents an analysis of McCormack's conceptual framework for person-centered practice with older people as a theoretical basis for the delivery of care of older adults in an Irish context. The evaluative process is guided by the framework proposed by Fawcett (2000) for the analysis and evaluation of conceptual models of nursing. The historical evolution, philosophical claims, and an overview of the content of the model are addressed. The following criteria are then applied: logical congruence, the generation of the theory, the credibility of the model, and the contribution of the model to the discipline of nursing.

  1. Thermalization and prethermalization in isolated quantum systems: a theoretical overview

    NASA Astrophysics Data System (ADS)

    Mori, Takashi; Ikeda, Tatsuhiko N.; Kaminishi, Eriko; Ueda, Masahito

    2018-06-01

    The approach to thermal equilibrium, or thermalization, in isolated quantum systems is among the most fundamental problems in statistical physics. Recent theoretical studies have revealed that thermalization in isolated quantum systems has several remarkable features, which emerge from quantum entanglement and are quite distinct from those in classical systems. Experimentally, well isolated and highly controllable ultracold quantum gases offer an ideal testbed to study the nonequilibrium dynamics in isolated quantum systems, promoting intensive recent theoretical endeavors on this fundamental subject. Besides thermalization, many isolated quantum systems show intriguing behavior in relaxation processes, especially prethermalization. Prethermalization occurs when there is a clear separation of relevant time scales and has several different physical origins depending on individual systems. In this review, we overview theoretical approaches to the problems of thermalization and prethermalization.

  2. Shadows and strong gravitational lensing: a brief review

    NASA Astrophysics Data System (ADS)

    Cunha, Pedro V. P.; Herdeiro, Carlos A. R.

    2018-04-01

    For ultra compact objects, light rings and fundamental photon orbits (FPOs) play a pivotal role in the theoretical analysis of strong gravitational lensing effects, and of BH shadows in particular. In this short review, specific models are considered to illustrate how FPOs can be useful in order to understand some non-trivial gravitational lensing effects. This paper aims at briefly overviewing the theoretical foundations of these effects, touching also some of the related phenomenology, both in general relativity and alternative theories of gravity, hopefully providing some intuition and new insights for the underlying physics, which might be critical when testing the Kerr black hole hypothesis.

  3. Theoretical Overview on the Improvement of Interest in Learning Theoretical Course for Engineering Students

    ERIC Educational Resources Information Center

    Xiao, Manlin; Zhang, Jianglin

    2016-01-01

    The phenomenon that engineering students have little interest in theoretical knowledge learning is more and more apparent. Therefore, most students fail to understand and apply theories to solve practical problems. To solve this problem, the importance of improving students' interest in the learning theoretical course is discussed firstly in this…

  4. A practitioner's guide to interpersonal communication theory: an overview and exploration of selected theories.

    PubMed

    Bylund, Carma L; Peterson, Emily B; Cameron, Kenzie A

    2012-06-01

    To provide a brief overview of selected interpersonal theories and models, and to present examples of their use in healthcare communication research. Nine interpersonal communication theories and their application to healthcare communication are discussed. As healthcare communication interactions often occur at an interpersonal level, familiarity with theories of interpersonal communication may reinforce existing best practices and lead to the development of novel communication approaches with patients. This article serves as an introductory primer to theories of interpersonal communication that have been or could be applied to healthcare communication research. Understanding key constructs and general formulations of these theories may provide practitioners with additional theoretical frameworks to use when interacting with patients. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  5. A practitioner’s guide to interpersonal communication theory: An overview and exploration of selected theories

    PubMed Central

    Bylund, Carma L.; Peterson, Emily B.; Cameron, Kenzie A.

    2011-01-01

    Objective To provide a brief overview of selected interpersonal theories and models, and to present examples of their use in healthcare communication research. Results Nine interpersonal communication theories and their application to healthcare communication are discussed. Conclusion As healthcare communication interactions often occur at an interpersonal level, familiarity with theories of interpersonal communication may reinforce existing best practices and lead to the development of novel communication approaches with patients. Practice Implications This article serves as an introductory primer to theories of interpersonal communication that have been or could be applied to healthcare communication research. Understanding key constructs and general formulations of these theories may provide practitioners with additional theoretical frameworks to use when interacting with patients. PMID:22112396

  6. The effects of detailed chemistry and transport on microgravity droplet combustion

    NASA Technical Reports Server (NTRS)

    Marchese, A. J.; Lee, J. C.; Held, T. J.; Dryer, F. L.

    1995-01-01

    A brief overview of recent advances in the theoretical study of microgravity droplet combustion is presented. Much of this work has centered on the development and utilization of sphero-symmetric transient numerical models which consider detailed gas phase chemistry and transport as well as energy and/or species transport within a regressing condensed phase. Numerical results for microgravity combustion and vaporization of methanol, methanol/water, heptane, and heptane/hexadecane droplets are summarized along with refinements in chemical kinetics and the development of a new two-dimensional axi-symmetric model.

  7. The Influence of the Enhanced Vector Meson Sector on the Properties of the Matter of Neutron Stars

    PubMed Central

    Bednarek, Ilona; Manka, Ryszard; Pienkos, Monika

    2014-01-01

    This paper gives an overview of the model of a neutron star with non-zero strangeness constructed within the framework of the nonlinear realization of the chiral symmetry. The emphasis is put on the physical properties of the matter of a neutron star as well as on its internal structure. The obtained solution is particularly aimed at the problem of the construction of a theoretical model of a neutron star matter with hyperons that will give high value of the maximum mass. PMID:25188304

  8. On the complex interplay between learning and dynamics in life sciences. Comment on the paper "Collective learning modeling based on the kinetic theory of active particles" by Burini et al.

    NASA Astrophysics Data System (ADS)

    Bellomo, Nicola; Elaiw, Ahmed; Alghamdi, Mohamed Ali

    2016-03-01

    The paper by Burini, De Lillo, and Gibelli [8] presents an overview and critical analysis of the literature on the modeling of learning dynamics. The first reference is the celebrated paper by Cucker and Smale [9]. Then, the authors also propose their own approach, based on suitable development of methods of the kinetic theory [6] and theoretical tools of evolutionary game theory [12,13], recently developed on graphs [2].

  9. Allostatic load: A theoretical model for understanding the relationship between maternal posttraumatic stress disorder and adverse birth outcomes.

    PubMed

    Li, Yang; Rosemberg, Marie-Anne Sanon; Seng, Julia S

    2018-07-01

    Adverse birth outcomes such as preterm birth and low birth weight are significant public health concerns and contribute to neonatal morbidity and mortality. Studies have increasingly been exploring the predictive effects of maternal posttraumatic stress disorder (PTSD) on adverse birth outcomes. However, the biological mechanisms by which maternal PTSD affects birth outcomes are not well understood. Allostatic load refers to the cumulative dysregulations of the multiple physiological systems as a response to multiple social-ecological levels of chronic stress. Allostatic load has been well documented in relation to both chronic stress and adverse health outcomes in non-pregnant populations. However, the mediating role of allostatic load is less understood when it comes to maternal PTSD and adverse birth outcomes. To propose a theoretical model that depicts how allostatic load could mediate the impact of maternal PTSD on birth outcomes. We followed the procedures for theory synthesis approach described by Walker and Avant (2011), including specifying focal concepts, identifying related factors and relationships, and constructing an integrated representation. We first present a theoretical overview of the allostatic load theory and the other 4 relevant theoretical models. Then we provide a brief narrative review of literature that empirically supports the propositions of the integrated model. Finally, we describe our theoretical model. The theoretical model synthesized has the potential to advance perinatal research by delineating multiple biomarkers to be used in future. After it is well validated, it could be utilized as the theoretical basis for health care professionals to identify high-risk women by evaluating their experiences of psychosocial and traumatic stress and to develop and evaluate service delivery and clinical interventions that might modify maternal perceptions or experiences of stress and eliminate their impacts on adverse birth outcomes. Copyright © 2018. Published by Elsevier Ltd.

  10. Relativistic GLONASS and geodesy

    NASA Astrophysics Data System (ADS)

    Mazurova, E. M.; Kopeikin, S. M.; Karpik, A. P.

    2016-12-01

    GNSS technology is playing a major role in applications to civil, industrial and scientific areas. Nowadays, there are two fully functional GNSS: American GPS and Russian GLONASS. Their data processing algorithms have been historically based on the Newtonian theory of space and time with only a few relativistic effects taken into account as small corrections preventing the system from degradation on a fairly long time. Continuously growing accuracy of geodetic measurements and atomic clocks suggests reconsidering the overall approach to the GNSS theoretical model based on the Einstein theory of general relativity. This is essentially more challenging but fundamentally consistent theoretical approach to relativistic space geodesy. In this paper, we overview the basic principles of the relativistic GNSS model and explain the advantages of such a system for GLONASS and other positioning systems. Keywords: relativistic GLONASS, Einstein theory of general relativity.

  11. Thermophysical Properties of Undercooled Alloys: An Overview of the Molecular Simulation Approaches

    PubMed Central

    Lv, Yong J.; Chen, Min

    2011-01-01

    We review the studies on the thermophysical properties of undercooled metals and alloys by molecular simulations in recent years. The simulation methods of melting temperature, enthalpy, specific heat, surface tension, diffusion coefficient and viscosity are introduced and the simulated results are summarized. By comparing the experimental results and various theoretical models, the temperature and the composition dependences of the thermophysical properties in undercooled regime are discussed. PMID:21339987

  12. Two dimensional Fourier transform methods for fringe pattern analysis

    NASA Astrophysics Data System (ADS)

    Sciammarella, C. A.; Bhat, G.

    An overview of the use of FFTs for fringe pattern analysis is presented, with emphasis on fringe patterns containing displacement information. The techniques are illustrated via analysis of the displacement and strain distributions in the direction perpendicular to the loading, in a disk under diametral compression. The experimental strain distribution is compared to the theoretical, and the agreement is found to be excellent in regions where the elasticity solution models well the actual problem.

  13. Modeling Viral Capsid Assembly

    PubMed Central

    2014-01-01

    I present a review of the theoretical and computational methodologies that have been used to model the assembly of viral capsids. I discuss the capabilities and limitations of approaches ranging from equilibrium continuum theories to molecular dynamics simulations, and I give an overview of some of the important conclusions about virus assembly that have resulted from these modeling efforts. Topics include the assembly of empty viral shells, assembly around single-stranded nucleic acids to form viral particles, and assembly around synthetic polymers or charged nanoparticles for nanotechnology or biomedical applications. I present some examples in which modeling efforts have promoted experimental breakthroughs, as well as directions in which the connection between modeling and experiment can be strengthened. PMID:25663722

  14. AN OVERVIEW OF THE DEVELOPMENT, STATUS, AND APPLICATION OF EQUILIBRIUM PARTITIONING SEDIMENT BENCHMARKS FOR PAH MIXTURES

    EPA Science Inventory

    This article provides an overview of the development, theoretical basis, regulatory status, and application of the U.S. Environmental Protection Agency's (USEPA's)< Equilibrium Partitioning Sediment Benchmarks (ESBs) for PAH mixtures. ESBs are compared to other sediment quality g...

  15. An Overview of a Theoretical Framework of Phenomenography in Qualitative Education Research: An Example from Physics Education Research

    ERIC Educational Resources Information Center

    Ornek, Funda

    2008-01-01

    One or more theoretical frameworks or orientations are used in qualitative education research. In this paper, the main tenets, the background and the appropriateness of phenomenography, which is one of the theoretical frameworks used in qualitative research, will be depicted. Further, the differences among phenomenography, phenomenology and…

  16. Peer Interventions to Promote Health: Conceptual Considerations

    PubMed Central

    Simoni, Jane M.; Franks, Julie C.; Lehavot, Keren; Yard, Samantha S.

    2013-01-01

    Peers have intervened to promote health since ancient times, yet few attempts have been made to describe theoretically their role and their interventions. After a brief overview of the history and variety of peer-based health interventions, a 4-part definition of peer interveners is presented here with a consideration of the dimensions of their involvement in health promotion. Then, a 2-step process is proposed as a means of conceptualizing peer interventions to promote health. Step 1 involves establishing a theoretical framework for the intervention’s main focus (i.e., education, social support, social norms, self-efficacy, and patient advocacy), and Step 2 involves identifying a theory that justifies the use of peers and might explain their impact. As examples, the following might be referred to: theoretical perspectives from the mutual support group and self-help literature, social cognitive and social learning theories, the social support literature, social comparison theory, social network approaches, and empowerment models. PMID:21729015

  17. Recent advances of nanotechnology in medicine and engineering

    NASA Astrophysics Data System (ADS)

    Nobile, Lucio; Nobile, Stefano

    2016-05-01

    The aim of this paper is to give an overview of some advances of nanotechnology in medicine and engineering, exploring typical applications of these emerging technologies. The mechanical properties of such small structures determine their utility and are therefore of considerable interest. Based on nanometer scale tests, a theoretical model to predict the bending strength of a nanobeam is proposed. A fracture approach which takes into account imperfections on the beam surface and crack growth is employed.

  18. Recent advances of nanotechnology in medicine and engineering

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

    Nobile, Lucio; Nobile, Stefano

    The aim of this paper is to give an overview of some advances of nanotechnology in medicine and engineering, exploring typical applications of these emerging technologies. The mechanical properties of such small structures determine their utility and are therefore of considerable interest. Based on nanometer scale tests, a theoretical model to predict the bending strength of a nanobeam is proposed. A fracture approach which takes into account imperfections on the beam surface and crack growth is employed.

  19. Collisions involving antiprotons and antihydrogen: an overview

    NASA Astrophysics Data System (ADS)

    Jonsell, S.

    2018-03-01

    I give an overview of experimental and theoretical results for antiproton and antihydrogen scattering with atoms and molecules (in particular H, He). At low energies (>1 keV) there are practically no experimental data available. Instead I compare the results from different theoretical calculations, of various degrees of sophistication. At energies up to a few tens of eV, I focus on simple approximations that give reasonably accurate results, as these allow quick estimates of collision rates without embarking on a research project. This article is part of the Theo Murphy meeting issue `Antiproton physics in the ELENA era'.

  20. Life course approach in social epidemiology: an overview, application and future implications.

    PubMed

    Cable, Noriko

    2014-01-01

    The application of the life course approach to social epidemiology has helped epidemiologists theoretically examine social gradients in population health. Longitudinal data with rich contextual information collected repeatedly and advanced statistical approaches have made this challenging task easier. This review paper provides an overview of the life course approach in epidemiology, its research application, and future challenges. In summary, a systematic approach to methods, including theoretically guided measurement of socioeconomic position, would assist researchers in gathering evidence for reducing social gradients in health, and collaboration across individual disciplines will make this task achievable.

  1. Visual Masking in Schizophrenia: Overview and Theoretical Implications

    PubMed Central

    Green, Michael F.; Lee, Junghee; Wynn, Jonathan K.; Mathis, Kristopher I.

    2011-01-01

    Visual masking provides several key advantages for exploring the earliest stages of visual processing in schizophrenia: it allows for control over timing at the millisecond level, there are several well-supported theories of the underlying neurobiology of visual masking, and it is amenable to examination by electroencephalogram (EEG) and functional magnetic resonance imaging (fMRI). In this paper, we provide an overview of the visual masking impairment schizophrenia, including the relevant theoretical mechanisms for masking impairment. We will discuss its relationship to clinical symptoms, antipsychotic medications, diagnostic specificity, and presence in at-risk populations. As part of this overview, we will cover the neural correlates of visual masking based on recent findings from EEG and fMRI. Finally, we will suggest a possible mechanism that could explain the patterns of masking findings and other visual processing findings in schizophrenia. PMID:21606322

  2. Oral contraceptives and mood in women with and without premenstrual dysphoria: a theoretical model.

    PubMed

    Kurshan, N; Neill Epperson, C

    2006-01-01

    Despite numerous studies on the topic, there is no consensus to date on the effects of oral contraceptives on mood or the mechanism(s) by which they exert these effects. This review article presents a theoretical model to explain the way in which oral contraceptives may affect mood. Specifically, it is argued that progestins exert differential effects on endogenous levels of neurosteroids, thereby altering mood. After providing an overview of the effects of estrogen, progesterone, and progesterone's metabolites on cortical excitability and the role of neurosteroids in depression and premenstrual dysphoria, this article reviews the research that has been conducted on the relationship between oral contraceptives and neurosteroids. Finally, suggestions for future research are made with the dual aim of improving existing studies on the relationship between oral contraceptives and mood and further investigating the possibility that fluctuations in neurosteroid levels are responsible for the effects of oral contraceptives on mood.

  3. Materiality in a Practice-Based Approach

    ERIC Educational Resources Information Center

    Svabo, Connie

    2009-01-01

    Purpose: The paper aims to provide an overview of the vocabulary for materiality which is used by practice-based approaches to organizational knowing. Design/methodology/approach: The overview is theoretically generated and is based on the anthology Knowing in Organizations: A Practice-based Approach edited by Nicolini, Gherardi and Yanow. The…

  4. Overview of Mediated Courseware in Learning Centers.

    ERIC Educational Resources Information Center

    Spangenberg, Ronald W.

    A limited overview of some media related factors, this document should be helpful to the learning center manager who lacks extensive experience with media. It discusses important theoretical factors associated with media selection and summarizes research concerning the use of color and of motion in learning. Descriptive information concerning…

  5. Academic Engagement: An Overview of Its Definitions, Dimensions, and Major Conceptualisations

    ERIC Educational Resources Information Center

    Alrashidi, Oqab; Phan, Huy P.; Ngu, Bing H.

    2016-01-01

    Engagement is a prominent theoretical orientation that has received great attention from educators and researchers. This article provides a literature overview of the engagement construct pertaining to its various definitions, dimensions, and major conceptualisations. In addition, the review sheds light on two major approaches to engagement in the…

  6. Constraining extended scalar sectors at the LHC and beyond

    NASA Astrophysics Data System (ADS)

    Ilnicka, Agnieszka; Robens, Tania; Stefaniak, Tim

    2018-04-01

    We give a brief overview of beyond the Standard Model (BSM) theories with an extended scalar sector and their phenomenological status in the light of recent experimental results. We discuss the relevant theoretical and experimental constraints, and show their impact on the allowed parameter space of two specific models: the real scalar singlet extension of the Standard Model (SM) and the Inert Doublet Model. We emphasize the importance of the LHC measurements, both the direct searches for additional scalar bosons, as well as the precise measurements of properties of the Higgs boson of mass 125 GeV. We show the complementarity of these measurements to electroweak and dark matter observables.

  7. The influence of the enhanced vector meson sector on the properties of the matter of neutron stars.

    PubMed

    Bednarek, Ilona; Manka, Ryszard; Pienkos, Monika

    2014-01-01

    This paper gives an overview of the model of a neutron star with non-zero strangeness constructed within the framework of the nonlinear realization of the chiral SU(3)L x SU(3)R symmetry. The emphasis is put on the physical properties of the matter of a neutron star as well as on its internal structure. The obtained solution is particularly aimed at the problem of the construction of a theoretical model of a neutron star matter with hyperons that will give high value of the maximum mass.

  8. Rotational relaxation of molecular hydrogen at moderate temperatures

    NASA Technical Reports Server (NTRS)

    Sharma, S. P.

    1994-01-01

    Using a coupled rotation-vibration-dissociation model the rotational relaxation times for molecular hydrogen as a function of final temperature (500-5000 K), in a hypothetical scenario of sudden compression, are computed. The theoretical model is based on a master equation solver. The bound-bound and bound-free transition rates have been computed using a quasiclassical trajectory method. A review of the available experimental data on the rotational relaxation of hydrogen is presented, with a critical overview of the method of measurements and data reduction, including the sources of errors. These experimental data are then compared with the computed results.

  9. A Diverse Community To Study Communities: Integration of Experiments and Mathematical Models To Study Microbial Consortia.

    PubMed

    Succurro, Antonella; Moejes, Fiona Wanjiku; Ebenhöh, Oliver

    2017-08-01

    The last few years have seen the advancement of high-throughput experimental techniques that have produced an extraordinary amount of data. Bioinformatics and statistical analyses have become instrumental to interpreting the information coming from, e.g., sequencing data and often motivate further targeted experiments. The broad discipline of "computational biology" extends far beyond the well-established field of bioinformatics, but it is our impression that more theoretical methods such as the use of mathematical models are not yet as well integrated into the research studying microbial interactions. The empirical complexity of microbial communities presents challenges that are difficult to address with in vivo / in vitro approaches alone, and with microbiology developing from a qualitative to a quantitative science, we see stronger opportunities arising for interdisciplinary projects integrating theoretical approaches with experiments. Indeed, the addition of in silico experiments, i.e., computational simulations, has a discovery potential that is, unfortunately, still largely underutilized and unrecognized by the scientific community. This minireview provides an overview of mathematical models of natural ecosystems and emphasizes that one critical point in the development of a theoretical description of a microbial community is the choice of problem scale. Since this choice is mostly dictated by the biological question to be addressed, in order to employ theoretical models fully and successfully it is vital to implement an interdisciplinary view at the conceptual stages of the experimental design. Copyright © 2017 Succurro et al.

  10. Optimization of MLS receivers for multipath environments

    NASA Technical Reports Server (NTRS)

    Mcalpine, G. A.; Highfill, J. H., III

    1979-01-01

    The angle tracking problems in microwave landing system receivers along with a receiver design capable of optimal performance in the multipath environments found in air terminal areas were studied. Included were various theoretical and evaluative studies like: (1) signal model development; (2) derivation of optimal receiver structures; and (3) development and use of computer simulations for receiver algorithm evaluation. The development of an experimental receiver for flight testing is presented. An overview of the work and summary of principal results and conclusions are reported.

  11. Advances in Experiment Design for High Performance Aircraft

    NASA Technical Reports Server (NTRS)

    Morelli, Engene A.

    1998-01-01

    A general overview and summary of recent advances in experiment design for high performance aircraft is presented, along with results from flight tests. General theoretical background is included, with some discussion of various approaches to maneuver design. Flight test examples from the F-18 High Alpha Research Vehicle (HARV) are used to illustrate applications of the theory. Input forms are compared using Cramer-Rao bounds for the standard errors of estimated model parameters. Directions for future research in experiment design for high performance aircraft are identified.

  12. Charged-particle multiplicity at LHC energies

    ScienceCinema

    Grosse-Oetringhaus, Jan Fiete

    2018-05-24

    The talk presents the measurement of the pseudorapidity density and the multiplicity distribution with ALICE at the achieved LHC energies of 0.9 and 2.36 TeV.An overview about multiplicity measurements prior to LHC is given and the related theoretical concepts are briefly discussed.The analysis procedure is presented and the systematic uncertainties are detailed. The applied acceptance corrections and the treatment of diffraction are discussed.The results are compared with model predictions. The validity of KNO scaling in restricted phase space regions is revisited. 

  13. Millimeter Continuum Observations Of Disk Solids

    NASA Astrophysics Data System (ADS)

    Andrews, Sean

    2016-07-01

    I will offer a condensed overview of some key issues in protoplanetary disk research that makes use interferometric measurements of the millimeter-wavelength continuum emitted by their solid particles. Several lines of evidence now qualitatively support theoretical models for the growth and migration of disk solids, but also advertise a quantitative tension with the traditional efficiency of that evolution. New observations of small-scale substructures in disks might both reconcile the conflict and shift our focus in the mechanics of planet formation.

  14. Avoidance learning: a review of theoretical models and recent developments

    PubMed Central

    Krypotos, Angelos-Miltiadis; Effting, Marieke; Kindt, Merel; Beckers, Tom

    2015-01-01

    Avoidance is a key characteristic of adaptive and maladaptive fear. Here, we review past and contemporary theories of avoidance learning. Based on the theories, experimental findings and clinical observations reviewed, we distill key principles of how adaptive and maladaptive avoidance behavior is acquired and maintained. We highlight clinical implications of avoidance learning theories and describe intervention strategies that could reduce maladaptive avoidance and prevent its return. We end with a brief overview of recent developments and avenues for further research. PMID:26257618

  15. Learning, Teaching and Assessment: A Theoretical Overview. SCRE Project Report No. 20.

    ERIC Educational Resources Information Center

    Black, Harry; And Others

    This overview of the literature on teaching, learning, and assessment was prepared to help develop a shared understanding by educators, researchers, and students to inform subsequent research conducted by the Scottish Council for Research in Education (SCRE) into the National Certificate in Scotland. Section 1 serves as an introduction to the…

  16. Visual Literacy. . .An Overview of Theory and Practice.

    ERIC Educational Resources Information Center

    DeSantis, Lucille Burbank; Pett, Dennis W.

    Visual Literacy is a field that encompasses a variety of theoretical constructs and practical considerations relating to communicating with visual signs. The theoretical constructs that influence visual communication primarily fall into two closely interrelated categories: those that relate to the individuals involved in the communication process,…

  17. Action Research: Theory and Applications

    ERIC Educational Resources Information Center

    Jefferson, Renée N.

    2014-01-01

    Action research as a methodology is suitable for use within academic library settings. Its theoretical foundations are located in several disciplines and its applications span across many professions. In this article, an overview of the theoretical beginnings and evolution of action research is presented. Approaches generally used in conducting an…

  18. Beyond the Language Classroom

    ERIC Educational Resources Information Center

    Benson, Phil, Ed.; Reinders, Hayo, Ed.

    2011-01-01

    This comprehensive exploration of theoretical and practical aspects of out-of-class teaching and learning, from a variety of perspectives and in various settings around the world, includes a theoretical overview of the field, 11 data-based case studies, and practical advice on materials development for independent learning. Contents of this book…

  19. Preservation of Newspapers: Theoretical Approaches and Practical Achievements

    ERIC Educational Resources Information Center

    Hasenay, Damir; Krtalic, Maja

    2010-01-01

    The preservation of newspapers is the main topic of this paper. A theoretical overview of newspaper preservation is given, with an emphasis on the importance of a systematic and comprehensive approach. Efficient newspaper preservation implies understanding the meaning of preservation in general, as well as understanding specific approaches,…

  20. Teacher Selection: Legal, Practical, and Theoretical Aspects. UCEA Monograph Series.

    ERIC Educational Resources Information Center

    Young, I. Philip; Ryerson, Dean

    This monograph, structured for administrative use in analyzing and building systems for selecting teachers, outlines the legal, applied, and theoretical issues of teacher selection. This overview is presented in five sections. "Legal Aspects of Teacher Selection" examines individual rights and employer reactions in relation to federal and state…

  1. Data, Methods, and Theoretical Implications

    ERIC Educational Resources Information Center

    Hannagan, Rebecca J.; Schneider, Monica C.; Greenlee, Jill S.

    2012-01-01

    Within the subfields of political psychology and the study of gender, the introduction of new data collection efforts, methodologies, and theoretical approaches are transforming our understandings of these two fields and the places at which they intersect. In this article we present an overview of the research that was presented at a National…

  2. From theory to field experiments

    NASA Astrophysics Data System (ADS)

    de Vos, Bram

    2016-04-01

    Peter Raats' achievements in Haren (NL) 1986-1997 were based on a solid theoretical insight in hydrology and transport process in soil. However, Peter was also the driving force behind many experimental studies and applied research. This will be illustrated by a broad range of examples ranging from the dynamics of composting processes of organic material; modelling and monitoring nutrient leaching at field-scale; wind erosion; water and nutrient dynamics in horticultural production systems; oxygen diffusion in soils; and processes of water and nutrient uptake by plant roots. Peter's leadership led to may new approaches and the introduction of innovative measurement techniques in Dutch research; ranging from TDR to nutrient concentration measurements in closed fertigation systems. This presentation will give a brief overview how Peter's theoretical and mathematical insights accelerated this applied research.

  3. Theoretical domains: a heuristic for teaching behavioral theory in HIV/STD prevention courses.

    PubMed

    Dolcini, M Margaret; Canin, Lisa; Gandelman, Alice; Skolnik, Heidi

    2004-10-01

    The HIV/STD epidemics have broadened the need for better behavioral intervention programs and highlighted the importance of providing training in behavioral theory to frontline program practitioners. However, there is a lack of effective methods for teaching theoretical concepts to people who may not have a background in behavioral science. This article presents a solution to this challenge by introducing a new heuristic for teaching theory and for placing individual theories/models in a broader context. Using a broad framework, we identify five domains that influence behavior: risk appraisal, self-perceptions, emotions and arousal, relationships and social influence, and environmental and structural factors. Each domain is described, and a brief overview of supporting literature is provided. Following the presentation of domains, we discuss course structure and activities.

  4. Impact of the rail-pad multi-discrete model upon the prediction of the rail response

    NASA Astrophysics Data System (ADS)

    Mazilu, T.; Leu, M.

    2017-08-01

    Wheel/rail vibration has many technical effects such as wear of the rolling surfaces, rolling noise, settlement of the ballast and subgrade etc. This vibration is depending on the rail pad characteristic and subsequently, it is important to have an accurate overview on the relation between the rail pad characteristic and the level of the wheel/rail vibration. To this end, much theoretical and experimental research has been developed in the past, and for the theoretical approach the track model, in general, and, particularly, the rail pad model is of crucial importance. Usually, the rail pad model is discrete model one, neglecting the length of the rail pad. This fact is questionable because the sleepers span is only 4 times the rail pad length. Using the rail pad discrete model, the rail response is overestimated when the frequency of the excitation equals the pinned-pinned resonance frequency. In this paper, a multi-discrete model for the rail pad, consisting in many Kelvin-Voigt parallel systems, is inserted into an analytical model of the track. The track model is reduced to a rail taken as infinite Timoshenko beam, discretely supported via rail pad, sleeper and ballast. The influence of the number of Kelvin-Voigt systems of the rail pad model on the rail response is analysed.

  5. The evolving concept of "patient-centeredness" in patient-physician communication research.

    PubMed

    Ishikawa, Hirono; Hashimoto, Hideki; Kiuchi, Takahiro

    2013-11-01

    Over the past few decades, the concept of "patient-centeredness" has been intensively studied in health communication research on patient-physician interaction. Despite its popularity, this concept has often been criticized for lacking a unified definition and operationalized measurement. This article reviews how health communication research on patient-physician interaction has conceptualized and operationalized patient-centered communication based on four major theoretical perspectives in sociology (i.e., functionalism, conflict theory, utilitarianism, and social constructionism), and discusses the agenda for future research in this field. Each theory addresses different aspects of the patient-physician relationship and communication from different theoretical viewpoints. Patient-centeredness is a multifaceted construct with no single theory that can sufficiently define the whole concept. Different theoretical perspectives of patient-centered communication can be selectively adopted according to the context and nature of problems in the patient-physician relationship that a particular study aims to explore. The present study may provide a useful framework: it offers an overview of the differing models of patient-centered communication and the expected roles and goals in each model; it does so toward identifying a communication model that fits the patient and the context and toward theoretically reconstructing existing measures of patient-centered communication. Furthermore, although patient-centered communication has been defined mainly from the viewpoint of physician's behaviors aimed at achieving patient-centered care, patient competence is also required for patient-centered communication. This needs to be examined in current medical practice. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Comparative Analysis of Theoretical Approaches to Professional Training of the Future Customs Officers in the System of Higher Education of Ukraine and Poland

    ERIC Educational Resources Information Center

    Korzhynska, Tetiana

    2015-01-01

    The article deals with the content of future customs officers' professional training. Such notions as "training", "specialists' professional training", "customs officers' professional training". The article presents an overview of the scientific literature, theoretical analyzes of materials concerning the issues of…

  7. A Literature Review of Gaming in Education. Research Report

    ERIC Educational Resources Information Center

    McClarty, Katie Larsen; Orr, Aline; Frey, Peter M.; Dolan, Robert P.; Vassileva, Victoria; McVay, Aaron

    2012-01-01

    The use of simulations and digital games in learning and assessment is expected to increase over the next several years. Although there is much theoretical support for the benefits of digital games in learning and education, there is mixed empirical support. This research report provides an overview of the theoretical and empirical evidence behind…

  8. Theories on Drug Abuse: Selected Contemporary Perspectives. Research Monograph 30.

    ERIC Educational Resources Information Center

    Lettieri, Dan J., Ed.; And Others

    This volume presents various theoretical orientations and perspectives of the drug abuse research field, derived from the social and biomedical sciences. The first section contains a separate theoretical overview for each of the 43 theories or perspectives. The second section contains five chapters which correspond to the five components of a drug…

  9. Neuroethics and animals: methods and philosophy.

    PubMed

    Takala, Tuija; Häyry, Matti

    2014-04-01

    This article provides an overview of the six other contributions in the Neuroethics and Animals special section. In addition, it discusses the methodological and theoretical problems of interdisciplinary fields. The article suggests that interdisciplinary approaches without established methodological and theoretical bases are difficult to assess scientifically. This might cause these fields to expand without actually advancing.

  10. Four Mechanistic Models of Peer Influence on Adolescent Cannabis Use.

    PubMed

    Caouette, Justin D; Feldstein Ewing, Sarah W

    2017-06-01

    Most adolescents begin exploring cannabis in peer contexts, but the neural mechanisms that underlie peer influence on adolescent cannabis use are still unknown. This theoretical overview elucidates the intersecting roles of neural function and peer factors in cannabis use in adolescents. Novel paradigms using functional magnetic resonance imaging (fMRI) in adolescents have identified distinct neural mechanisms of risk decision-making and incentive processing in peer contexts, centered on reward-motivation and affect regulatory neural networks; these findings inform a theoretical model of peer-driven cannabis use decisions in adolescents. We propose four "mechanistic profiles" of social facilitation of cannabis use in adolescents: (1) peer influence as the primary driver of use; (2) cannabis exploration as the primary driver, which may be enhanced in peer contexts; (3) social anxiety; and (4) negative peer experiences. Identification of "neural targets" involved in motivating cannabis use may inform clinicians about which treatment strategies work best in adolescents with cannabis use problems, and via which social and neurocognitive processes.

  11. The Adaptation of the Immigrant Second Generation in America: Theoretical Overview and Recent Evidence

    PubMed Central

    Portes, Alejandro; Fernández-Kelly, Patricia; Haller, William

    2013-01-01

    This paper summarises a research program on the new immigrant second generation initiated in the early 1990s and completed in 2006. The four field waves of the Children of Immigrants Longitudinal Study (CILS) are described and the main theoretical models emerging from it are presented and graphically summarised. After considering critical views of this theory, we present the most recent results from this longitudinal research program in the forum of quantitative models predicting downward assimilation in early adulthood and qualitative interviews identifying ways to escape it by disadvantaged children of immigrants. Quantitative results strongly support the predicted effects of exogenous variables identified by segmented assimilation theory and identify the intervening factors during adolescence that mediate their influence on adult outcomes. Qualitative evidence gathered during the last stage of the study points to three factors that can lead to exceptional educational achievement among disadvantaged youths. All three indicate the positive influence of selective acculturation. Implications of these findings for theory and policy are discussed. PMID:23626483

  12. An Overview of Recent Advances in Event-Triggered Consensus of Multiagent Systems.

    PubMed

    Ding, Lei; Han, Qing-Long; Ge, Xiaohua; Zhang, Xian-Ming

    2018-04-01

    Event-triggered consensus of multiagent systems (MASs) has attracted tremendous attention from both theoretical and practical perspectives due to the fact that it enables all agents eventually to reach an agreement upon a common quantity of interest while significantly alleviating utilization of communication and computation resources. This paper aims to provide an overview of recent advances in event-triggered consensus of MASs. First, a basic framework of multiagent event-triggered operational mechanisms is established. Second, representative results and methodologies reported in the literature are reviewed and some in-depth analysis is made on several event-triggered schemes, including event-based sampling schemes, model-based event-triggered schemes, sampled-data-based event-triggered schemes, and self-triggered sampling schemes. Third, two examples are outlined to show applicability of event-triggered consensus in power sharing of microgrids and formation control of multirobot systems, respectively. Finally, some challenging issues on event-triggered consensus are proposed for future research.

  13. Health crises and media relations: relationship management-by-fire.

    PubMed

    Springston, Jeffrey K; Weaver-Lariscy, Ruthann

    2007-01-01

    Media relations is an important function in the operation of any health organization, yet it is often relegated as a simple task function. Such an orientation can be problematic, particularly in times of crisis. This article provides an overview of some of the inherent internal conflicts within health organizations that may mitigate against the best media relations practices in times of crises. The article surveys some of the predominant theoretical models used for crisis management, and suggests directions for the further development of media relations and crisis communication theory and practice.

  14. Theoretical and experimental investigations of upper atmosphere dynamics

    NASA Technical Reports Server (NTRS)

    Roper, R. G.; Edwards, H. D.

    1980-01-01

    A brief overview of the significant contributions made to the understanding of the dynamics of the Earth's upper atmosphere is presented, including the addition of winds and diffusion to the semi-empirical Global Reference Atmospheric Model developed for the design phase of the Space Shuttle, reviews of turbulence in the lower thermosphere, the dynamics of the equatorial mesopause, stratospheric warming effects on mesopause level dynamics, and the relevance of these studies to the proposed Middle Atmosphere Program (1982-85). A chronological bibliography, with abstracts of all papers published, is also included.

  15. International Hypersonic Waverider Symposium, 1st, University of Maryland, College Park, MD, Oct. 17-19, 1990, Proceedings

    NASA Technical Reports Server (NTRS)

    Anderson, John D., Jr. (Editor); Lewis, Mark J. (Editor); Corda, Stephen (Editor); Blankson, Isaiah M. (Editor)

    1990-01-01

    The papers presented in this volume provide an overview of current theoretical and experimental research in the field of hypersonic waveriders. In particular, attention is given to efficient waveriders from known axisymmetric flow fields, hypersonic waverider design from given shock waves, limitations of waveriders, and aerodynamic stability theory of hypersonic waveriders. The discussion also covers momentum analysis of waverider flow fields, tethered aerothermodynamic research for hypersonic waveriders, simulation of hypersonic waveriders, and an idealized tip-to-tail waverider model.

  16. Cataclysmic variables and related objects

    NASA Technical Reports Server (NTRS)

    Hack, Margherita; Ladous, Constanze; Jordan, Stuart D. (Editor); Thomas, Richard N. (Editor); Goldberg, Leo; Pecker, Jean-Claude

    1993-01-01

    This volume begins with an introductory chapter on general properties of cataclysmic variables. Chapters 2 through 5 of Part 1 are devoted to observations and interpretation of dwarf novae and nova-like stars. Chapters 6 through 10, Part 2, discuss the general observational properties of classical and recurrent novae, the theoretical models, and the characteristics and models for some well observed classical novae and recurrent novae. Chapters 11 through 14 of Part 3 are devoted to an overview of the observations of symbiotic stars, to a description of the various models proposed for explaining the symbiotic phenomenon, and to a discussion of a few selected objects, respectively. Chapter 15 briefly examines the many unsolved problems posed by the observations of the different classes of cataclysmic variables and symbiotic stars.

  17. Experimental Validation of a Thermoelastic Model for SMA Hybrid Composites

    NASA Technical Reports Server (NTRS)

    Turner, Travis L.

    2001-01-01

    This study presents results from experimental validation of a recently developed model for predicting the thermomechanical behavior of shape memory alloy hybrid composite (SMAHC) structures, composite structures with an embedded SMA constituent. The model captures the material nonlinearity of the material system with temperature and is capable of modeling constrained, restrained, or free recovery behavior from experimental measurement of fundamental engineering properties. A brief description of the model and analysis procedures is given, followed by an overview of a parallel effort to fabricate and characterize the material system of SMAHC specimens. Static and dynamic experimental configurations for the SMAHC specimens are described and experimental results for thermal post-buckling and random response are presented. Excellent agreement is achieved between the measured and predicted results, fully validating the theoretical model for constrained recovery behavior of SMAHC structures.

  18. Potential flow theory and operation guide for the panel code PMARC

    NASA Technical Reports Server (NTRS)

    Ashby, Dale L.; Dudley, Michael R.; Iguchi, Steve K.; Browne, Lindsey; Katz, Joseph

    1991-01-01

    The theoretical basis for PMARC, a low-order potential-flow panel code for modeling complex three-dimensional geometries, is outlined. Several of the advanced features currently included in the code, such as internal flow modeling, a simple jet model, and a time-stepping wake model, are discussed in some detail. The code is written using adjustable size arrays so that it can be easily redimensioned for the size problem being solved and the computer hardware being used. An overview of the program input is presented, with a detailed description of the input available in the appendices. Finally, PMARC results for a generic wing/body configuration are compared with experimental data to demonstrate the accuracy of the code. The input file for this test case is given in the appendices.

  19. The Future of Theoretical Physics and Cosmology

    NASA Astrophysics Data System (ADS)

    Gibbons, G. W.; Shellard, E. P. S.; Rankin, S. J.

    2003-11-01

    Based on lectures given in honor of Stephen Hawking's 60th birthday, this book comprises contributions from the world's leading theoretical physicists. Popular lectures progress to a critical evaluation of more advanced subjects in modern cosmology and theoretical physics. Topics covered include the origin of the universe, warped spacetime, cosmological singularities, quantum gravity, black holes, string theory, quantum cosmology and inflation. The volume provides a fascinating overview of the variety of subjects to which Stephen Hawking has contributed.

  20. Denial of Chronic Illness and Disability: Part I. Theoretical, Functional, and Dynamic Perspectives

    ERIC Educational Resources Information Center

    Livneh, Hanoch

    2009-01-01

    Denial has been an integral part of the psychological and disability literature for more than 100 years. Yet, denial is an elusive concept and has been associated with mixed, indeed conflicting, theoretical perspectives, clinical strategies, and empirical findings. In this two-part article, the author provides an overview of the existing…

  1. A Study on the Models for Corporate Social Responsibility of Small and Medium Enterprises

    NASA Astrophysics Data System (ADS)

    Ma, Jun

    The role of small and medium enterprises (SMEs) in corporate social responsibility (CSR) has attracted increasing attention and interest in recent years. The purpose of this study is to build some relevant models of CSR which are the foundations of empirical study later. The paper begins by an overview of the CSR literature in the context of seven step model for CSR and differences between corporate and small businesses. Noting the general lack of theoretical framework in the literature, the paper then presents relevant theoretical models of CSR that could be useful in conducting further research on CSR and SMEs. The study is qualitative in nature, capitalizing on a comparative research design to highlight differences in CSR orientations between SMEs and MNCs. The research is presented and implications are drawn regarding the peculiar relational attributes of SMEs in the context of CSR generally, and developing countries more specifically, and how this inclination can be further nurtured and leveraged. Further research can seek to highlight how to leverage this natural affinity to CSR among SMEs detected in this study in pursuit of more systematic engagement and more benefits.

  2. Cognitive-behavioural theories of helplessness/hopelessness: valid models of depression?

    PubMed

    Henkel, V; Bussfeld, P; Möller, H-J; Hegerl, U

    2002-10-01

    Helplessness and hopelessness are central aspects of cognitive-behavioural explanations for the development and persistence of depression. In this article a general overview concerning the evolution of those approaches to depression is provided. Included is a critical examination of the theories. The review of the literature suggests that those cognitive models describing helplessness/hopelessness as trait factors mediating depression do not really have a strong empirical base. The majority of those studies had been conducted in healthy or only mildly depressed subjects. Thus, there seems to be little justification for broad generalisations beyond the populations studied. It seems that some of the reported studies have not tested the underlying theories adequately (e. g. correlation had sometimes been interpreted as causation; adequate prospective longitudinal study designs had seldom been applied). Moreover, the theoretical models are not generally prepared to explain all depressive features (e. g. the possibility of a spontaneous shift in a manic episode). Despite those limitations, there is a relevant impact of the learned helplessness paradigm on preclinical research in neurobiological correlates of depressive states. Last but not least, the models are of high interest with respect to the theoretical background of important modules of cognitive-behavioural therapy and its acute and prophylactic effects.

  3. The Dynamics of Planet Formation

    NASA Astrophysics Data System (ADS)

    Chambers, J. E.

    2005-05-01

    The transformation of a protoplanetary disk of gas and dust into a system of planets is a mysterious business that is frustratingly difficult to observe in detail. For this reason, studies of planet formation are largely based on theoretical models with only a few anchor points where precious observations are available. In this talk I will give an overview of some of these theoretical models, indicating areas of uncertainty and places where the models are on firmer ground. For convenience, theorists usually divide planet formation into a series of stages: formation of solid bodies from dust, aggregation of solid bodies into protoplanets, late-stage growth and the formation of giant planets, and planetary migration. Here I will concentrate mostly on the second and third of these stages (understanding of the first and last stages is rather limited, and the author's understanding is especially so). The intermediate stages involve interplay between several physical processes: physical collisions, gravitational scattering, dynamical friction, gas drag, and the capture and collapse of atmospheres. I will describe these processes in some detail, and show using analytical models how these effects can lead to a variety of planetary outcomes. This work was supported by NASA's Planetary Geology and Geophysics and TPF Foundation Science Mission programmes.

  4. Mathematical modeling of gonadotropin-releasing hormone signaling.

    PubMed

    Pratap, Amitesh; Garner, Kathryn L; Voliotis, Margaritis; Tsaneva-Atanasova, Krasimira; McArdle, Craig A

    2017-07-05

    Gonadotropin-releasing hormone (GnRH) acts via G-protein coupled receptors on pituitary gonadotropes to control reproduction. These are G q -coupled receptors that mediate acute effects of GnRH on the exocytotic secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), as well as the chronic regulation of their synthesis. GnRH is secreted in short pulses and GnRH effects on its target cells are dependent upon the dynamics of these pulses. Here we overview GnRH receptors and their signaling network, placing emphasis on pulsatile signaling, and how mechanistic mathematical models and an information theoretic approach have helped further this field. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  5. A brief review on relaxor ferroelectrics and selected issues in lead-free relaxors

    NASA Astrophysics Data System (ADS)

    Ahn, Chang Won; Hong, Chang-Hyo; Choi, Byung-Yul; Kim, Hwang-Pill; Han, Hyoung-Su; Hwang, Younghun; Jo, Wook; Wang, Ke; Li, Jing-Feng; Lee, Jae-Shin; Kim, Ill Won

    2016-06-01

    Relaxor ferroelectricity is one of the most widely investigated but the least understood material classes in the condensed matter physics. This is largely due to the lack of experimental tools that decisively confirm the existing theoretical models. In spite of the diversity in the models, they share the core idea that the observed features in relaxors are closely related to localized chemical heterogeneity. Given this, this review attempts to overview the existing models of importance chronologically, from the diffuse phase transition model to the random-field model and to show how the core idea has been reflected in them to better shape our insight into the nature of relaxor-related phenomena. Then, the discussion will be directed to how the models of a common consensus, developed with the so-called canonical relaxors such as Pb(Mg1/3Nb2/3)O3 (PMN) and (Pb, La)(Zr, Ti)O3 (PLZT), are compatible with phenomenological explanations for the recently identified relaxors such as (Bi1/2Na1/2)TiO3 (BNT)-based lead-free ferroelectrics. This review will be finalized with a discussion on the theoretical aspects of recently introduced 0-3 and 2-2 ferroelectric/relaxor composites as a practical tool for strain engineering.

  6. Predicting Electrostatic Forces in RNA Folding

    PubMed Central

    Tan, Zhi-Jie; Chen, Shi-Jie

    2016-01-01

    Metal ion-mediated electrostatic interactions are critical to RNA folding. Although considerable progress has been made in mechanistic studies, the problem of accurate predictions for the ion effects in RNA folding remains unsolved, mainly due to the complexity of several potentially important issues such as ion correlation and dehydration effects. In this chapter, after giving a brief overview of the experimental findings and theoretical approaches, we focus on a recently developed new model, the tightly bound ion (TBI) model, for ion electrostatics in RNA folding. The model is unique because it can treat ion correlation and fluctuation effects for realistic RNA 3D structures. For monovalent ion (such as Na+) solutions, where ion correlation is weak, TBI and the Poisson–Boltzmann (PB) theory give the same results and the results agree with the experimental data. For multivalent ion (such as Mg2+) solutions, where ion correlation can be strong, however, TBI gives much improved predictions than the PB. Moreover, the model suggests an ion correlation- induced mechanism for the unusual efficiency of Mg2+ ions in the stabilization of RNA tertiary folds. In this chapter, after introducing the theoretical framework of the TBI model, we will describe how to apply the model to predict ion-binding properties and ion-dependent folding stabilities. PMID:20946803

  7. Theoretical models for supercritical fluid extraction.

    PubMed

    Huang, Zhen; Shi, Xiao-Han; Jiang, Wei-Juan

    2012-08-10

    For the proper design of supercritical fluid extraction processes, it is essential to have a sound knowledge of the mass transfer mechanism of the extraction process and the appropriate mathematical representation. In this paper, the advances and applications of kinetic models for describing supercritical fluid extraction from various solid matrices have been presented. The theoretical models overviewed here include the hot ball diffusion, broken and intact cell, shrinking core and some relatively simple models. Mathematical representations of these models have been in detail interpreted as well as their assumptions, parameter identifications and application examples. Extraction process of the analyte solute from the solid matrix by means of supercritical fluid includes the dissolution of the analyte from the solid, the analyte diffusion in the matrix and its transport to the bulk supercritical fluid. Mechanisms involved in a mass transfer model are discussed in terms of external mass transfer resistance, internal mass transfer resistance, solute-solid interactions and axial dispersion. The correlations of the external mass transfer coefficient and axial dispersion coefficient with certain dimensionless numbers are also discussed. Among these models, the broken and intact cell model seems to be the most relevant mathematical model as it is able to provide realistic description of the plant material structure for better understanding the mass-transfer kinetics and thus it has been widely employed for modeling supercritical fluid extraction of natural matters. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Perceptual awareness and its neural basis: bridging experimental and theoretical paradigms

    PubMed Central

    Raffone, Antonino; Srinivasan, Narayanan; van Leeuwen, Cees

    2014-01-01

    Understanding consciousness is a major scientific challenge of our times, and perceptual awareness is an integral part of that challenge. This Theme Issue aims to provide a timely focus on crucial insights from leading scientists on perceptual awareness and its neural basis. The issue refers to key research questions and findings in perceptual awareness research and aims to be a catalyst for further research, by bringing together the state-of-the-art. It shows how bridges are being built between empirical and theoretical research and proposes new directions for the study of multisensory awareness and the role of the states of the body therein. In this introduction, we highlight crucial problems that have characterized the development of the study of perceptual awareness. We then provide an overview of major experimental and theoretical paradigms related to perceptual awareness and its neural basis. Finally, we present an overview of the Theme Issue, with reference to the contributed articles and their relationships. PMID:24639576

  9. Probabilistic choice models in health-state valuation research: background, theories, assumptions and applications.

    PubMed

    Arons, Alexander M M; Krabbe, Paul F M

    2013-02-01

    Interest is rising in measuring subjective health outcomes, such as treatment outcomes that are not directly quantifiable (functional disability, symptoms, complaints, side effects and health-related quality of life). Health economists in particular have applied probabilistic choice models in the area of health evaluation. They increasingly use discrete choice models based on random utility theory to derive values for healthcare goods or services. Recent attempts have been made to use discrete choice models as an alternative method to derive values for health states. In this article, various probabilistic choice models are described according to their underlying theory. A historical overview traces their development and applications in diverse fields. The discussion highlights some theoretical and technical aspects of the choice models and their similarity and dissimilarity. The objective of the article is to elucidate the position of each model and their applications for health-state valuation.

  10. A Heated Debate: Theoretical Perspectives of Sexual Exploitation and Sex Work

    PubMed Central

    Gerassi, Lara

    2015-01-01

    The theoretical and often political framework of sexual exploitation and sex work among women is widely and enthusiastically debated among academic and legal scholars alike. The majority of theoretical literature in this area focuses on the macro perspective, while the micro-level perspective as to theory and causation remains sparse. This article provides a comprehensive overview of the philosophical, legal, and political perspectives pertaining to sexual exploitation of women and girls while addressing the subsequent controversies in the field. PMID:26834302

  11. RELATIVISTIC HEAVY ION PHYSICS: A THEORETICAL OVERVIEW.

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

    KHARZEEV,D.

    2004-03-28

    This is a mini-review of recent theoretical work in the field of relativistic heavy ion physics. The following topics are discussed initial conditions and the Color Glass Condensate; approach to thermalization and the hydrodynamic evolution; hard probes and the properties of the Quark-Gluon Plasma. Some of the unsolved problems and potentially promising directions for future research are listed as well.

  12. Diversity and Women's Career Development: From Adolescence to Adulthood. Women's Mental Health and Development, Volume 2.

    ERIC Educational Resources Information Center

    Farmer, Helen S.

    This book presents a variety of perspectives on career development for women that grew from an extensive study of high school students in 1980 with follow-ups in 1990 and 1993. "Theoretical Overview: The Longitudinal Study" (Helen S. Farmer) outlines the social learning theoretical framework underlying the study and describes study procedures,…

  13. [A Survey of the Factors of Influence and Interventional Strategies for Breast Cancer Survivors' Transition Care Across Multiple Theoretical Perspectives].

    PubMed

    Chao, Yu-Huan; Lee, Tzu-I; Sheu, Shuh-Jen

    2018-02-01

    Breast cancer significantly threatens the life of women, while the adverse effects of cancer treatment degrade quality of life and psychological well-being. The quality of transitional care following the completion of treatment significantly affects the ability of breast cancer patients to transition successfully into survivorship. This paper introduces multiple theoretical perspectives and provides an overview of the tenets of each in order to identify the positions of breast cancer survivors and to highlight the factors and strategies that influence their transitional care. The theoretical perspectives that are introduced include the social-ecological model, transition theory, and the strengths perspective. In order to improve the holistic care of women with breast cancer, factors relevant to transition are categorized into the individual, interpersonal, organizational, community, and policy levels. Furthermore, empirical interventions, which are based on the respective advantages of the various levels of the social-ecological model, are proposed in order to conform to the sociocultural context and clinical practices. Healthcare providers should leverage the strengths and resources at each level to develop feasible strategies and to provide quality of care in order to assist breast cancer patients to transition successfully from treatment to survivorship and to holistically improve their subsequent quality of life and function.

  14. The ODD protocol: A review and first update

    USGS Publications Warehouse

    Grimm, Volker; Berger, Uta; DeAngelis, Donald L.; Polhill, J. Gary; Giske, Jarl; Railsback, Steve F.

    2010-01-01

    The 'ODD' (Overview, Design concepts, and Details) protocol was published in 2006 to standardize the published descriptions of individual-based and agent-based models (ABMs). The primary objectives of ODD are to make model descriptions more understandable and complete, thereby making ABMs less subject to criticism for being irreproducible. We have systematically evaluated existing uses of the ODD protocol and identified, as expected, parts of ODD needing improvement and clarification. Accordingly, we revise the definition of ODD to clarify aspects of the original version and thereby facilitate future standardization of ABM descriptions. We discuss frequently raised critiques in ODD but also two emerging, and unanticipated, benefits: ODD improves the rigorous formulation of models and helps make the theoretical foundations of large models more visible. Although the protocol was designed for ABMs, it can help with documenting any large, complex model, alleviating some general objections against such models.

  15. A Decision Model for Supporting Task Allocation Processes in Global Software Development

    NASA Astrophysics Data System (ADS)

    Lamersdorf, Ansgar; Münch, Jürgen; Rombach, Dieter

    Today, software-intensive systems are increasingly being developed in a globally distributed way. However, besides its benefit, global development also bears a set of risks and problems. One critical factor for successful project management of distributed software development is the allocation of tasks to sites, as this is assumed to have a major influence on the benefits and risks. We introduce a model that aims at improving management processes in globally distributed projects by giving decision support for task allocation that systematically regards multiple criteria. The criteria and causal relationships were identified in a literature study and refined in a qualitative interview study. The model uses existing approaches from distributed systems and statistical modeling. The article gives an overview of the problem and related work, introduces the empirical and theoretical foundations of the model, and shows the use of the model in an example scenario.

  16. Status of the \\varvec{Λ (1405)}

    NASA Astrophysics Data System (ADS)

    Mai, Maxim

    2018-07-01

    I give an overview of the current status of the lowest s-wave baryon resonance in the strangeness (S=-1) channel, the Λ (1405). Recent results from Lattice QCD calculations and new high-precision data from photoproduction experiments are highlighted in this talk. On the theoretical side various directions have been explored over the last two decades on the basis of coupled-channel chiral unitary models. New photoproduction data can be used to reduce statistical uncertainty of the predictions of such models. As for the systematic uncertainties, a recent comparative analysis of modern approaches exhibits many similarities but also large ambiguities in some of the predicted properties of the antikaon-nucleon scattering amplitudes. Some possible ways to reduce such a model dependence are discussed at the end of this manuscript.

  17. Multicriteria decision analysis: Overview and implications for environmental decision making

    USGS Publications Warehouse

    Hermans, Caroline M.; Erickson, Jon D.; Erickson, Jon D.; Messner, Frank; Ring, Irene

    2007-01-01

    Environmental decision making involving multiple stakeholders can benefit from the use of a formal process to structure stakeholder interactions, leading to more successful outcomes than traditional discursive decision processes. There are many tools available to handle complex decision making. Here we illustrate the use of a multicriteria decision analysis (MCDA) outranking tool (PROMETHEE) to facilitate decision making at the watershed scale, involving multiple stakeholders, multiple criteria, and multiple objectives. We compare various MCDA methods and their theoretical underpinnings, examining methods that most realistically model complex decision problems in ways that are understandable and transparent to stakeholders.

  18. The challenge of identifying greenhouse gas-induced climatic change

    NASA Technical Reports Server (NTRS)

    Maccracken, Michael C.

    1992-01-01

    Meeting the challenge of identifying greenhouse gas-induced climatic change involves three steps. First, observations of critical variables must be assembled, evaluated, and analyzed to determine that there has been a statistically significant change. Second, reliable theoretical (model) calculations must be conducted to provide a definitive set of changes for which to search. Third, a quantitative and statistically significant association must be made between the projected and observed changes to exclude the possibility that the changes are due to natural variability or other factors. This paper provides a qualitative overview of scientific progress in successfully fulfilling these three steps.

  19. TMDs and SSAs in hadronic interactions

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

    Aschenauer, E. C.; D’Alesio, U.; Murgia, F.

    2016-06-17

    Here we present an overview on the current experimental and phenomenological status of transverse single spin asymmetries (tSSAs) in proton-proton collisions. In particular, we focus on large- pT inclusive pion, photon, jet, pion-jet production and Drell-Yan processes. For all of them theoretical estimates are given in terms of a generalised parton model (GPM) based on a transverse momentum dependent (TMD) factorisation scheme. We also make comparisons with the corresponding results in a collinear twist-3 formalism and in a modified GPM approach. On the experimental side, a selection of the most interesting and recent results from RHIC is presented.

  20. Resource Letter MPCVW-1: Modeling Political Conflict, Violence, and Wars: A Survey

    NASA Astrophysics Data System (ADS)

    Morgenstern, Ana P.; Velásquez, Nicolás; Manrique, Pedro; Hong, Qi; Johnson, Nicholas; Johnson, Neil

    2013-11-01

    This Resource Letter provides a guide into the literature on modeling and explaining political conflict, violence, and wars. Although this literature is dominated by social scientists, multidisciplinary work is currently being developed in the wake of myriad methodological approaches that have sought to analyze and predict political violence. The works covered herein present an overview of this abundance of methodological approaches. Since there is a variety of possible data sets and theoretical approaches, the level of detail and scope of models can vary quite considerably. The review does not provide a summary of the available data sets, but instead highlights recent works on quantitative or multi-method approaches to modeling different forms of political violence. Journal articles and books are organized in the following topics: social movements, diffusion of social movements, political violence, insurgencies and terrorism, and civil wars.

  1. The Economic Importance of Financial Literacy: Theory and Evidence

    PubMed Central

    Lusardi, Annamaria; Mitchell, Olivia S.

    2017-01-01

    This paper undertakes an assessment of a rapidly growing body of economic research on financial literacy. We start with an overview of theoretical research which casts financial knowledge as a form of investment in human capital. Endogenizing financial knowledge has important implications for welfare as well as policies intended to enhance levels of financial knowledge in the larger population. Next, we draw on recent surveys to establish how much (or how little) people know and identify the least financially savvy population subgroups. This is followed by an examination of the impact of financial literacy on economic decision-making in the United States and elsewhere. While the literature is still young, conclusions may be drawn about the effects and consequences of financial illiteracy and what works to remedy these gaps. A final section offers thoughts on what remains to be learned if researchers are to better inform theoretical and empirical models as well as public policy. PMID:28579637

  2. The Economic Importance of Financial Literacy: Theory and Evidence.

    PubMed

    Lusardi, Annamaria; Mitchell, Olivia S

    2014-03-01

    This paper undertakes an assessment of a rapidly growing body of economic research on financial literacy. We start with an overview of theoretical research which casts financial knowledge as a form of investment in human capital. Endogenizing financial knowledge has important implications for welfare as well as policies intended to enhance levels of financial knowledge in the larger population. Next, we draw on recent surveys to establish how much (or how little) people know and identify the least financially savvy population subgroups. This is followed by an examination of the impact of financial literacy on economic decision-making in the United States and elsewhere. While the literature is still young, conclusions may be drawn about the effects and consequences of financial illiteracy and what works to remedy these gaps. A final section offers thoughts on what remains to be learned if researchers are to better inform theoretical and empirical models as well as public policy.

  3. Why should we care about the top quark Yukawa coupling?

    DOE PAGES

    Shapshnikov, Mikhail; Bezrukov, Fedor

    2015-04-15

    In the cosmological context, for the Standard Model to be valid up to the scale of inflation, the top quark Yukawa coupling y t should not exceed the critical value y t crit , coinciding with good precision (about 0.2‰) with the requirement of the stability of the electroweak vacuum. So, the exact measurements of y t may give an insight on the possible existence and the energy scale of new physics above 100 GeV, which is extremely sensitive to y t. In this study, we overview the most recent theoretical computations of and the experimental measurements of y tmore » crit and the experimental measurements of y t. Within the theoretical and experimental uncertainties in y t, the required scale of new physics varies from 10⁷ GeV to the Planck scale, urging for precise determination of the top quark Yukawa coupling.« less

  4. Modeling semiflexible polymer networks

    NASA Astrophysics Data System (ADS)

    Broedersz, C. P.; MacKintosh, F. C.

    2014-07-01

    This is an overview of theoretical approaches to semiflexible polymers and their networks. Such semiflexible polymers have large bending rigidities that can compete with the entropic tendency of a chain to crumple up into a random coil. Many studies on semiflexible polymers and their assemblies have been motivated by their importance in biology. Indeed, cross-linked networks of semiflexible polymers form a major structural component of tissue and living cells. Reconstituted networks of such biopolymers have emerged as a new class of biological soft matter systems with remarkable material properties, which have spurred many of the theoretical developments discussed here. Starting from the mechanics and dynamics of individual semiflexible polymers, the physics of semiflexible bundles, entangled solutions, and disordered cross-linked networks are reviewed. Finally, recent developments on marginally stable fibrous networks, which exhibit critical behavior similar to other marginal systems such as jammed soft matter, are discussed.

  5. The halogen bond: Nature and applications

    NASA Astrophysics Data System (ADS)

    Costa, Paulo J.

    2017-10-01

    The halogen bond, corresponding to an attractive interaction between an electrophilic region in a halogen (X) and a nucleophile (B) yielding a R-X⋯B contact, found applications in many fields such as supramolecular chemistry, crystal engineering, medicinal chemistry, and chemical biology. Their large range of applications also led to an increased interest in their study using computational methods aiming not only at understanding the phenomena at a fundamental level, but also to help in the interpretation of results and guide the experimental work. Herein, a succinct overview of the recent theoretical and experimental developments is given starting by discussing the nature of the halogen bond and the latest theoretical insights on this topic. Then, the effects of the surrounding environment on halogen bonds are presented followed by a presentation of the available method benchmarks. Finally, recent experimental applications where the contribution of computational chemistry was fundamental are discussed, thus highlighting the synergy between the lab and modeling techniques.

  6. Imaging neural signatures of consciousness: 'what', 'when', 'where' and 'how' does it work?

    PubMed

    Sergent, C; Naccache, L

    2012-01-01

    'What' do we call consciousness? 'When' and 'Where' in the brain do conscious states occur, and 'How' conscious processing and conscious access to a given content work? In the present paper, we present a non-exhaustive overview of each of these 4 major issues, we provide the reader with a brief description of the major difficulties related to these issues, we highlight the current theoretical points of debate, and we advocate for the explanatory power of the "global workspace" model of consciousness (Baars 1989; Dehaene and Naccache 2001; Dehaene, Changeux et al. 2006) which can accommodate for a fairly large proportion of current experimental findings, and which can be used to reinterpret apparent contradictory findings within a single theoretical framework. Most notably, we emphasize the crucial importance to distinguish genuine neural signatures of conscious access from neural events correlated with consciousness but occurring either before ('upstream') or after ('downstream').

  7. Computational models of music perception and cognition II: Domain-specific music processing

    NASA Astrophysics Data System (ADS)

    Purwins, Hendrik; Grachten, Maarten; Herrera, Perfecto; Hazan, Amaury; Marxer, Ricard; Serra, Xavier

    2008-09-01

    In Part I [Purwins H, Herrera P, Grachten M, Hazan A, Marxer R, Serra X. Computational models of music perception and cognition I: The perceptual and cognitive processing chain. Physics of Life Reviews 2008, in press, doi:10.1016/j.plrev.2008.03.004], we addressed the study of cognitive processes that underlie auditory perception of music, and their neural correlates. The aim of the present paper is to summarize empirical findings from music cognition research that are relevant to three prominent music theoretic domains: rhythm, melody, and tonality. Attention is paid to how cognitive processes like category formation, stimulus grouping, and expectation can account for the music theoretic key concepts in these domains, such as beat, meter, voice, consonance. We give an overview of computational models that have been proposed in the literature for a variety of music processing tasks related to rhythm, melody, and tonality. Although the present state-of-the-art in computational modeling of music cognition definitely provides valuable resources for testing specific hypotheses and theories, we observe the need for models that integrate the various aspects of music perception and cognition into a single framework. Such models should be able to account for aspects that until now have only rarely been addressed in computational models of music cognition, like the active nature of perception and the development of cognitive capacities from infancy to adulthood.

  8. Roy Schafer: a beginning.

    PubMed

    Schwartz, Henry P

    2013-01-01

    The author provides a biographical overview of Schafer's life, culled from his published work and focused primarily on his professional development. This biography is used to demonstrate some of Schafer's central theoretical insights on narrativity and language, and reveals the consistency of his thinking over his long career. A brief discussion of his writing on King Lear provides a bridge between theoretical and biographical material. © 2013 The Psychoanalytic Quarterly, Inc.

  9. A Critical Review of the Use of Wenger's Community of Practice (CoP) Theoretical Framework in Online and Blended Learning Research, 2000-2014

    ERIC Educational Resources Information Center

    Smith, Sedef Uzuner; Hayes, Suzanne; Shea, Peter

    2017-01-01

    After presenting a brief overview of the key elements that underpin Etienne Wenger's communities of practice (CoP) theoretical framework, one of the most widely cited and influential conceptions of social learning, this paper reviews extant empirical work grounded in this framework to investigate online/blended learning in higher education and in…

  10. Standard representation and unified stability analysis for dynamic artificial neural network models.

    PubMed

    Kim, Kwang-Ki K; Patrón, Ernesto Ríos; Braatz, Richard D

    2018-02-01

    An overview is provided of dynamic artificial neural network models (DANNs) for nonlinear dynamical system identification and control problems, and convex stability conditions are proposed that are less conservative than past results. The three most popular classes of dynamic artificial neural network models are described, with their mathematical representations and architectures followed by transformations based on their block diagrams that are convenient for stability and performance analyses. Classes of nonlinear dynamical systems that are universally approximated by such models are characterized, which include rigorous upper bounds on the approximation errors. A unified framework and linear matrix inequality-based stability conditions are described for different classes of dynamic artificial neural network models that take additional information into account such as local slope restrictions and whether the nonlinearities within the DANNs are odd. A theoretical example shows reduced conservatism obtained by the conditions. Copyright © 2017. Published by Elsevier Ltd.

  11. Four Mechanistic Models of Peer Influence on Adolescent Cannabis Use

    PubMed Central

    Caouette, Justin D.; Feldstein Ewing, Sarah W.

    2017-01-01

    Purpose of review Most adolescents begin exploring cannabis in peer contexts, but the neural mechanisms that underlie peer influence on adolescent cannabis use are still unknown. This theoretical overview elucidates the intersecting roles of neural function and peer factors in cannabis use in adolescents. Recent findings Novel paradigms using functional magnetic resonance imaging (fMRI) in adolescents have identified distinct neural mechanisms of risk decision-making and incentive processing in peer contexts, centered on reward-motivation and affect regulatory neural networks; these findings inform a theoretical model of peer-driven cannabis use decisions in adolescents. Summary We propose four “mechanistic profiles” of social facilitation of cannabis use in adolescents: (1) peer influence as the primary driver of use; (2) cannabis exploration as the primary driver, which may be enhanced in peer contexts; (3) social anxiety; and (4) negative peer experiences. Identification of “neural targets” involved in motivating cannabis use may inform clinicians about which treatment strategies work best in adolescents with cannabis use problems, and via which social and neurocognitive processes. PMID:29104847

  12. Reserves in load capacity assessment of existing bridges

    NASA Astrophysics Data System (ADS)

    Žitný, Jan; Ryjáček, Pavel

    2017-09-01

    High percentage of all railway bridges in the Czech Republic is made of structural steel. Majority of these bridges is designed according to historical codes and according to the deterioration, they have to be assessed if they satisfy the needs of modern railway traffic. The load capacity assessment of existing bridges according to Eurocodes is however often too conservative and especially, braking and acceleration forces cause huge problems to structural elements of the bridge superstructure. The aim of this paper is to review the different approaches for the determination of braking and acceleration forces. Both, current and historical theoretical models and in-situ measurements are considered. The research of several local European state norms superior to Eurocode for assessment of existing railway bridges shows the big diversity of used local approaches and the conservativeness of Eurocode. This paper should also work as an overview for designers dealing with load capacity assessment, revealing the reserves for existing bridges. Based on these different approaches, theoretical models and data obtained from the measurements, the method for determination of braking and acceleration forces on the basis of real traffic data should be proposed.

  13. Models and materials for generalized Kitaev magnetism

    NASA Astrophysics Data System (ADS)

    Winter, Stephen M.; Tsirlin, Alexander A.; Daghofer, Maria; van den Brink, Jeroen; Singh, Yogesh; Gegenwart, Philipp; Valentí, Roser

    2017-12-01

    The exactly solvable Kitaev model on the honeycomb lattice has recently received enormous attention linked to the hope of achieving novel spin-liquid states with fractionalized Majorana-like excitations. In this review, we analyze the mechanism proposed by Jackeli and Khaliullin to identify Kitaev materials based on spin-orbital dependent bond interactions and provide a comprehensive overview of its implications in real materials. We set the focus on experimental results and current theoretical understanding of planar honeycomb systems (Na2IrO3, α-Li2IrO3, and α-RuCl3), three-dimensional Kitaev materials (β- and γ-Li2IrO3), and other potential candidates, completing the review with the list of open questions awaiting new insights.

  14. Understanding the coping process from a self-determination theory perspective.

    PubMed

    Ntoumanis, Nikos; Edmunds, Jemma; Duda, Joan L

    2009-05-01

    To explore conceptual links between the cognitive-motivational-relational theory (CMRT) of coping (Lazarus, 1991) and self-determination theory (SDT) of motivation (Deci & Ryan, 1985). We present a very brief overview of the two theories. We also discuss how components from the two theories can be examined together to facilitate research in the health/exercise domain. To this effect, we offer a preliminary integrated model of stress, coping, and motivation, based on the two aforementioned theories, in an attempt to illustrate and instigate research on how motivational factors are implicated in the coping process. We believe that the proposed model can serve as a platform for generating new research ideas which, besides their theoretical relevance, may have important applied implications.

  15. Critical Medical Anthropology in Midwifery Research

    PubMed Central

    Newnham, Elizabeth C.; Pincombe, Jan I.; McKellar, Lois V.

    2016-01-01

    In this article, we discuss the use of critical medical anthropology (CMA) as a theoretical framework for research in the maternity care setting. With reference to the doctoral research of the first author, we argue for the relevance of using CMA for research into the maternity care setting, particularly as it relates to midwifery. We then give an overview of an existing analytic model within CMA that we adapted for looking specifically at childbirth practices and which was then used in both analyzing the data and structuring the thesis. There is often no clear guide to the analysis or writing up of data in ethnographic research; we therefore offer this Critical analytic model of childbirth practices for other researchers conducting ethnographic research into childbirth or maternity care. PMID:28462347

  16. The economic value of remote sensing of earth resources from space: An ERTS overview and the value of continuity of service. Volume 3: Intensive use of living resources, agriculture. Part 2: Distribution effects

    NASA Technical Reports Server (NTRS)

    Bradford, D. F.; Kelejian, H. H.

    1974-01-01

    The results of an investigation of the value of improving information for forecasting future crop harvests are described. A theoretical model is developed to calculate the value of increased speed of availablitiy of that information. The analysis of U.S. domestic wheat consumption was implemented. New estimates of a demand function for wheat and of a cost of storage function were involved, along with a Monte Carlo simulation for the wheat spot and future markets and a model of market determinations of wheat inventories. Results are shown to depend critically on the accuracy of current and proposed measurement techniques.

  17. Absorption of Solar Radiation by Clouds: An Overview

    NASA Technical Reports Server (NTRS)

    Tsay, Si-Chee; Einaudi, Franco (Technical Monitor)

    2000-01-01

    This talk provides an overview of the subject of absorption of solar radiation by clouds in the earth's atmosphere. The paper summarizes the available evidence which points to disagreements between theoretical and observed values of cloud absorption (and reflections). The importance of these discrepancies, particularly to remote sensing of clouds as well as to studies of cloud physics and earth radiation budgets, is emphasized. Existing cloud absorption and reflection measurements are reviewed and the persistent differences that exist between calculated and measured near-infrared cloud albedos are highlighted. Various explanations for these reflection and absorption discrepancies are discussed under two separate paths: a theoretician's approach and an experimentalist's approach. Examples for the former approach include model accuracy tests, large-droplet hypothesis, excess absorbing aerosol, enhanced water vapor continuum absorption, and effects of cloud inhomogeneity. The latter approach focuses on discussions of instrumental device, calibration, operational strategy, and signal/noise separation. A recommendation for future activities on this subject will be given.

  18. Non-Invasive Investigation of Bone Adaptation in Humans to Mechanical Loading

    NASA Technical Reports Server (NTRS)

    Whalen, R.

    1999-01-01

    Experimental studies have identified peak cyclic forces, number of loading cycles, and loading rate as contributors to the regulation of bone metabolism. We have proposed a theoretical model that relates bone density to a mechanical stimulus derived from average daily cumulative peak cyclic 'effective' tissue stresses. In order to develop a non-invasive experimental model to test the theoretical model we need to: (1) monitor daily cumulative loading on a bone, (2) compute the internal stress state(s) resulting from the imposed loading, and (3) image volumetric bone density accurately, precisely, and reproducibly within small contiguous volumes throughout the bone. We have chosen the calcaneus (heel) as an experimental model bone site because it is loaded by ligament, tendon and joint contact forces in equilibrium with daily ground reaction forces that we can measure; it is a peripheral bone site and therefore more easily and accurately imaged with computed tomography; it is composed primarily of cancellous bone; and it is a relevant site for monitoring bone loss and adaptation in astronauts and the general population. This paper presents an overview of our recent advances in the areas of monitoring daily ground reaction forces, biomechanical modeling of the forces on the calcaneus during gait, mathematical modeling of calcaneal bone adaptation in response to cumulative daily activity, accurate and precise imaging of the calcaneus with quantitative computed tomography (QCT), and application to long duration space flight.

  19. Gagne's Learning Theory Applied to Technical Instruction

    ERIC Educational Resources Information Center

    Lawson, Tom E.

    1974-01-01

    An overview of Robert M. Gagne's theoretical position of learning and instruction is presented with a discussion of possible applications and usefulness of the theory toward the development of technical instruction. (Author/AG)

  20. Panorama of theoretical physics

    NASA Astrophysics Data System (ADS)

    Mimouni, J.

    2012-06-01

    We shall start this panorama of theoretical physics by giving an overview of physics in general, this branch of knowledge that has been taken since the scientific revolution as the archetype of the scientific discipline. We shall then proceed in showing in what way theoretical physics from Newton to Maxwell, Einstein, Feynman and the like, in all modesty, could be considered as the ticking heart of physics. By its special mode of inquiry and its tantalizing successes, it has capturing the very spirit of the scientific method, and indeed it has been taken as a role model by other disciplines all the way from the "hard" ones to the social sciences. We shall then review how much we know today of the world of matter, both in term of its basic content and in the way it is structured. We will then present the dreams of today's theoretical physics as a way of penetrating into its psyche, discovering in this way its aspirations and longing in much the same way that a child's dreams tell us about his yearning and craving. Yet our understanding of matter has been going in the past decades through a crisis of sort. As a necessary antidote, we shall thus discuss the pitfalls of dreams pushed too far….

  1. Superconductivity and spin-orbit coupling in non-centrosymmetric materials: a review

    NASA Astrophysics Data System (ADS)

    Smidman, M.; Salamon, M. B.; Yuan, H. Q.; Agterberg, D. F.

    2017-03-01

    In non-centrosymmetric superconductors, where the crystal structure lacks a centre of inversion, parity is no longer a good quantum number and an electronic antisymmetric spin-orbit coupling (ASOC) is allowed to exist by symmetry. If this ASOC is sufficiently large, it has profound consequences on the superconducting state. For example, it generally leads to a superconducting pairing state which is a mixture of spin-singlet and spin-triplet components. The possibility of such novel pairing states, as well as the potential for observing a variety of unusual behaviors, led to intensive theoretical and experimental investigations. Here we review the experimental and theoretical results for superconducting systems lacking inversion symmetry. Firstly we give a conceptual overview of the key theoretical results. We then review the experimental properties of both strongly and weakly correlated bulk materials, as well as two dimensional systems. Here the focus is on evaluating the effects of ASOC on the superconducting properties and the extent to which there is evidence for singlet-triplet mixing. This is followed by a more detailed overview of theoretical aspects of non-centrosymmetric superconductivity. This includes the effects of the ASOC on the pairing symmetry and the superconducting magnetic response, magneto-electric effects, superconducting finite momentum pairing states, and the potential for non-centrosymmetric superconductors to display topological superconductivity.

  2. Dynamic Responses and Vibration Control of the Transmission Tower-Line System: A State-of-the-Art Review

    PubMed Central

    Chen, Bo; Guo, Wei-hua; Li, Peng-yun; Xie, Wen-ping

    2014-01-01

    This paper presented an overview on the dynamic analysis and control of the transmission tower-line system in the past forty years. The challenges and future developing trends in the dynamic analysis and mitigation of the transmission tower-line system under dynamic excitations are also put forward. It also reviews the analytical models and approaches of the transmission tower, transmission lines, and transmission tower-line systems, respectively, which contain the theoretical model, finite element (FE) model and the equivalent model; shows the advances in wind responses of the transmission tower-line system, which contains the dynamic effects under common wind loading, tornado, downburst, and typhoon; and discusses the dynamic responses under earthquake and ice loads, respectively. The vibration control of the transmission tower-line system is also reviewed, which includes the magnetorheological dampers, friction dampers, tuned mass dampers, and pounding tuned mass dampers. PMID:25105161

  3. Computational Modeling of Cobalt-Based Water Oxidation: Current Status and Future Challenges

    PubMed Central

    Schilling, Mauro; Luber, Sandra

    2018-01-01

    A lot of effort is nowadays put into the development of novel water oxidation catalysts. In this context, mechanistic studies are crucial in order to elucidate the reaction mechanisms governing this complex process, new design paradigms and strategies how to improve the stability and efficiency of those catalysts. This review is focused on recent theoretical mechanistic studies in the field of homogeneous cobalt-based water oxidation catalysts. In the first part, computational methodologies and protocols are summarized and evaluated on the basis of their applicability toward real catalytic or smaller model systems, whereby special emphasis is laid on the choice of an appropriate model system. In the second part, an overview of mechanistic studies is presented, from which conceptual guidelines are drawn on how to approach novel studies of catalysts and how to further develop the field of computational modeling of water oxidation reactions. PMID:29721491

  4. Theories of Giant Planet Formation

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.; Young, Richard E. (Technical Monitor)

    1998-01-01

    An overview of current theories of planetary formation, with emphasis on giant planets, is presented. The most detailed models are based upon observations of our own Solar System and of young stars and their environments. While these models predict that rocky planets should form around most single stars, the frequency of formation of gas giant planets is more difficult to predict theoretically. Terrestrial planets are believed to grow via pairwise accretion until the spacing of planetary orbits becomes large enough that the configuration is stable for the age of the system. Giant planets begin their growth as do terrestrial planets, but they become massive enough that they are able to accumulate substantial amounts of gas before the protoplanetary disk dissipates. Most models for extrasolar giant planets suggest that they formed as did Jupiter and Saturn (in nearly circular orbits, far enough from the star that ice could), and subsequently migrated to their current positions, although some models suggest in situ formation.

  5. The problem of fouling in submerged membrane bioreactors - Model validation and experimental evidence

    NASA Astrophysics Data System (ADS)

    Tsibranska, Irene; Vlaev, Serafim; Tylkowski, Bartosz

    2018-01-01

    Integrating biological treatment with membrane separation has found a broad area of applications and industrial attention. Submerged membrane bioreactors (SMBRs), based on membrane modules immersed in the bioreactor, or side stream ones connected in recycle have been employed in different biotechnological processes for separation of thermally unstable products. Fouling is one of the most important challenges in the integrated SMBRs. A number of works are devoted to fouling analysis and its treatment, especially exploring the opportunity for enhanced fouling control in SMBRs. The main goal of the review is to provide a comprehensive yet concise overview of modeling the fouling in SMBRs in view of the problematics of model validation, either by real system measurements at different scales or by analysis of the obtained theoretical results. The review is focused on the current state of research applying computational fluid dynamics (CFD) modeling techniques.

  6. Computational Modeling of Cobalt-based Water Oxidation: Current Status and Future Challenges

    NASA Astrophysics Data System (ADS)

    Schilling, Mauro; Luber, Sandra

    2018-04-01

    A lot of effort is nowadays put into the development of novel water oxidation catalysts. In this context mechanistic studies are crucial in order to elucidate the reaction mechanisms governing this complex process, new design paradigms and strategies how to improve the stability and efficiency of those catalysis. This review is focused on recent theoretical mechanistic studies in the field of homogeneous cobalt-based water oxidation catalysts. In the first part, computational methodologies and protocols are summarized and evaluated on the basis of their applicability towards real catalytic or smaller model systems, whereby special emphasis is laid on the choice of an appropriate model system. In the second part, an overview of mechanistic studies is presented, from which conceptual guidelines are drawn on how to approach novel studies of catalysts and how to further develop the field of computational modeling of water oxidation reactions.

  7. Principles and Heuristics for Designing Minimalist Instruction.

    ERIC Educational Resources Information Center

    van der Meij, Hans; Carroll, John M.

    1995-01-01

    Presents an overview of principles and heuristics for designing minimalist instruction, with examples and theoretical or empirical arguments. Provides a starting point from which to create minimalist instruction to suit a variety of uses. (SR)

  8. Theoretical overview and modeling of the sodium and potassium atmospheres of the moon

    NASA Technical Reports Server (NTRS)

    Smyth, William H.; Marconi, M. L.

    1995-01-01

    A general theoretical overview for the sources, sinks, gas-surface interactions, and transport dynamics of sodium and potassium in the exospheric atmosphere of the Moon is given. These four factors, which control the spatial distribution of these two alkali-group gases about the Moon, are incorporated in numerical models. The spatial nature and relative importance of the initial source atoms atmosphere (which must be nonthermal to explain observational data) and the ambient (ballistic hopping) atom atmosphere are examined. The transport dynamics, atmospheric structure, and lunar escape of the nonthermal source atoms are time variable with season of the year and lunar phase because of their dependence on the radiation acceleration experienced by sodium and potassium atoms as they resonantly scatter solar photons. The dynamic transport time of fully thermally accomodated ambient atoms along the surface because of solar radiation acceleration (only several percent of surface gravity) is larger than the photoionization lifetimes and hence unimportant in determining the local density, although for potassium the situation is borderline. The sodium model was applied to analyze sodium observations of the sunward brightness profiles acquired near last quarter by Potter & Morgan (1988b) extending from the surface to an altitude of 1200 km, and near first quarter by Mendillo, Baumgardner, & Flynn (1991), extending in altitude from approximately 1430 to approximately 7000 km. The observations at larger altitudes could be fitted only for source atoms having a velocity distribution with a tail that is mildly nonthermal (like an approximately 1000 K Maxwell-Boltzmann distribution). Solar wind sputtering appears to a be a viable source atom mechanism for the sodium observations with photon-simulated desorption also possible but highly uncertain, although micrometeoroid impact vaporization appears to have a source that is too small and too hot, with likely an incorrect angular distribution about the Moon.

  9. Progress in Spin Dynamics Solid-State Nuclear Magnetic Resonance with the Application of Floquet-Magnus Expansion to Chemical Shift Anisotropy

    PubMed Central

    Mananga, Eugene Stephane

    2013-01-01

    The purpose of this article is to present an historical overview of theoretical approaches used for describing spin dynamics under static or rotating experiments in solid state nuclear magnetic resonance. The article gives a brief historical overview for major theories in nuclear magnetic resonance and the promising theories. We present the first application of Floquet-Magnus expansion to chemical shift anisotropy when irradiated by BABA pulse sequence. PMID:23711337

  10. Pharmaceutical cocrystals: an overview.

    PubMed

    Qiao, Ning; Li, Mingzhong; Schlindwein, Walkiria; Malek, Nazneen; Davies, Angela; Trappitt, Gary

    2011-10-31

    Pharmaceutical cocrystals are emerging as a new class of solid drugs with improved physicochemical properties, which has attracted increased interests from both industrial and academic researchers. In this paper a brief and systematic overview of pharmaceutical cocrystals is provided, with particular focus on cocrystal design strategies, formation methods, physicochemical property studies, characterisation techniques, and recent theoretical developments in cocrystal screening and mechanisms of cocrystal formations. Examples of pharmaceutical cocrystals are also summarised in this paper. Copyright © 2011 Elsevier B.V. All rights reserved.

  11. Measuring cognition in teams: a cross-domain review.

    PubMed

    Wildman, Jessica L; Salas, Eduardo; Scott, Charles P R

    2014-08-01

    The purpose of this article is twofold: to provide a critical cross-domain evaluation of team cognition measurement options and to provide novice researchers with practical guidance when selecting a measurement method. A vast selection of measurement approaches exist for measuring team cognition constructs including team mental models, transactive memory systems, team situation awareness, strategic consensus, and cognitive processes. Empirical studies and theoretical articles were reviewed to identify all of the existing approaches for measuring team cognition. These approaches were evaluated based on theoretical perspective assumed, constructs studied, resources required, level of obtrusiveness, internal consistency reliability, and predictive validity. The evaluations suggest that all existing methods are viable options from the point of view of reliability and validity, and that there are potential opportunities for cross-domain use. For example, methods traditionally used only to measure mental models may be useful for examining transactive memory and situation awareness. The selection of team cognition measures requires researchers to answer several key questions regarding the theoretical nature of team cognition and the practical feasibility of each method. We provide novice researchers with guidance regarding how to begin the search for a team cognition measure and suggest several new ideas regarding future measurement research. We provide (1) a broad overview and evaluation of existing team cognition measurement methods, (2) suggestions for new uses of those methods across research domains, and (3) critical guidance for novice researchers looking to measure team cognition.

  12. Modeling language and cognition with deep unsupervised learning: a tutorial overview

    PubMed Central

    Zorzi, Marco; Testolin, Alberto; Stoianov, Ivilin P.

    2013-01-01

    Deep unsupervised learning in stochastic recurrent neural networks with many layers of hidden units is a recent breakthrough in neural computation research. These networks build a hierarchy of progressively more complex distributed representations of the sensory data by fitting a hierarchical generative model. In this article we discuss the theoretical foundations of this approach and we review key issues related to training, testing and analysis of deep networks for modeling language and cognitive processing. The classic letter and word perception problem of McClelland and Rumelhart (1981) is used as a tutorial example to illustrate how structured and abstract representations may emerge from deep generative learning. We argue that the focus on deep architectures and generative (rather than discriminative) learning represents a crucial step forward for the connectionist modeling enterprise, because it offers a more plausible model of cortical learning as well as a way to bridge the gap between emergentist connectionist models and structured Bayesian models of cognition. PMID:23970869

  13. Modeling language and cognition with deep unsupervised learning: a tutorial overview.

    PubMed

    Zorzi, Marco; Testolin, Alberto; Stoianov, Ivilin P

    2013-01-01

    Deep unsupervised learning in stochastic recurrent neural networks with many layers of hidden units is a recent breakthrough in neural computation research. These networks build a hierarchy of progressively more complex distributed representations of the sensory data by fitting a hierarchical generative model. In this article we discuss the theoretical foundations of this approach and we review key issues related to training, testing and analysis of deep networks for modeling language and cognitive processing. The classic letter and word perception problem of McClelland and Rumelhart (1981) is used as a tutorial example to illustrate how structured and abstract representations may emerge from deep generative learning. We argue that the focus on deep architectures and generative (rather than discriminative) learning represents a crucial step forward for the connectionist modeling enterprise, because it offers a more plausible model of cortical learning as well as a way to bridge the gap between emergentist connectionist models and structured Bayesian models of cognition.

  14. Theoretical models for duct acoustic propagation and radiation

    NASA Technical Reports Server (NTRS)

    Eversman, Walter

    1991-01-01

    The development of computational methods in acoustics has led to the introduction of analysis and design procedures which model the turbofan inlet as a coupled system, simultaneously modeling propagation and radiation in the presence of realistic internal and external flows. Such models are generally large, require substantial computer speed and capacity, and can be expected to be used in the final design stages, with the simpler models being used in the early design iterations. Emphasis is given to practical modeling methods that have been applied to the acoustical design problem in turbofan engines. The mathematical model is established and the simplest case of propagation in a duct with hard walls is solved to introduce concepts and terminologies. An extensive overview is given of methods for the calculation of attenuation in uniform ducts with uniform flow and with shear flow. Subsequent sections deal with numerical techniques which provide an integrated representation of duct propagation and near- and far-field radiation for realistic geometries and flight conditions.

  15. A systems theoretic approach to analysis and control of mammalian circadian dynamics

    PubMed Central

    Abel, John H.; Doyle, Francis J.

    2016-01-01

    The mammalian circadian clock is a complex multi-scale, multivariable biological control system. In the past two decades, methods from systems engineering have led to numerous insights into the architecture and functionality of this system. In this review, we examine the mammalian circadian system through a process systems lens. We present a mathematical framework for examining the cellular circadian oscillator, and show recent extensions for understanding population-scale dynamics. We provide an overview of the routes by which the circadian system can be systemically manipulated, and present in silico proof of concept results for phase resetting of the clock via model predictive control. PMID:28496287

  16. Corporate information systems in health organisations.

    PubMed

    Smith, J

    1997-01-01

    This paper presents an overview of the nature of corporate information systems and their applications in health organisations. It emphasises the importance of financial and human resource information in the creation of a corporate data model. The paper summarises the main features of finance and human resource systems as they are used in health organisations. It looks at a series of case studies carried out in health organisations, which were selected on the basis of their representation of different aspects of service delivery. It also discusses the theoretical and practical perspectives of the systems themselves, their roles in information management, executive and decision support, and in planning and forecasting.

  17. Physical conditions, dynamics, and mass distribution in the center of the Galaxy

    NASA Technical Reports Server (NTRS)

    Genzel, R.; Townes, C. H.

    1987-01-01

    Recent observations and theoretical models of the Galactic center (GC) are reviewed. An overview of phenomena seen in the GC is given, including the stellar cluster, radio continuum emission and interstellar clouds, the Sgr A complex, and X-ray and gamma emission. Also discussed are the energetics and physical conditions in the central 4 pc (star burst or central source?); the circumnuclear ring, ionized streamers, and relativistic and hot gas in the cavity; the mass distribution and the possibility of a massive black hole, and the central 0.1 pc (Sgr A and IRS 16). Diagrams, graphs, photographs, and tables of numerical data are provided.

  18. Book Review

    NASA Astrophysics Data System (ADS)

    Clevers, J. G. P. W.

    2015-02-01

    About thirty years after the previous advanced textbook on Microwave Remote Sensing by Ulaby, Moore and Fung has been published as three separate volumes, now an up-to-date new textbook has been published. The 1000-page book covers theoretical models, system design and operation, and geoscientific applications of active and passive microwave remote sensing systems. It is designed as a textbook at the postgraduate level, as well as a reference for the practicing professional. The book is caught by a thorough introduction into the physics and mathematics of electrical engineering applied to microwave radiation. Here on overview of its chapters with a short description of its focus will be given.

  19. Nuclear Data and Reaction Rate Databases in Nuclear Astrophysics

    NASA Astrophysics Data System (ADS)

    Lippuner, Jonas

    2018-06-01

    Astrophysical simulations and models require a large variety of micro-physics data, such as equation of state tables, atomic opacities, properties of nuclei, and nuclear reaction rates. Some of the required data is experimentally accessible, but the extreme conditions present in many astrophysical scenarios cannot be reproduced in the laboratory and thus theoretical models are needed to supplement the empirical data. Collecting data from various sources and making them available as a database in a unified format is a formidable task. I will provide an overview of the data requirements in astrophysics with an emphasis on nuclear astrophysics. I will then discuss some of the existing databases, the science they enable, and their limitations. Finally, I will offer some thoughts on how to design a useful database.

  20. On a non-thermal atmospheric pressure plasma jet used for the deposition of silicon-organic films

    NASA Astrophysics Data System (ADS)

    Schäfer, Jan; Sigeneger, Florian; Foest, Rüdiger; Loffhagen, Detlef; Weltmann, Klaus-Dieter

    2018-05-01

    This work represents a concise overview on the results achieved by the authors over the last years on the plasma of a non-thermal reactive plasma jet at atmospheric pressure and of related thin film formation by plasma enhanced chemical vapour deposition (PECVD). The source was developed considering the application of the plasma self-organization for PECVD. The experimental methods comprise spectroscopic measurements of plasma parameters in the active zone, temperature measurements in the active zone and the effluent as well as the analysis of deposited films at the substrate surface. The theoretical investigations are devoted to a single filament in the active zone using a phase-resolved model and to an overall description of the jet including the substrate using a period-averaged model.

  1. The AMIDAS Website: An Online Tool for Direct Dark Matter Detection Experiments

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

    Shan, Chung-Lin

    2010-02-10

    Following our long-erm work on development of model-independent data analysis methods for reconstructing the one-dimensional velocity distribution function of halo WIMPs as well as for determining their mass and couplings on nucleons by using data from direct Dark Matter detection experiments directly, we combined the simulation programs to a compact system: AMIDAS (A Model-Independent Data Analysis System). For users' convenience an online system has also been established at the same time. AMIDAS has the ability to do full Monte Carlo simulations, faster theoretical estimations, as well as to analyze (real) data sets recorded in direct detection experiments without modifying themore » source code. In this article, I give an overview of functions of the AMIDAS code based on the use of its website.« less

  2. Critical Medical Anthropology in Midwifery Research: A Framework for Ethnographic Analysis.

    PubMed

    Newnham, Elizabeth C; Pincombe, Jan I; McKellar, Lois V

    2016-01-01

    In this article, we discuss the use of critical medical anthropology (CMA) as a theoretical framework for research in the maternity care setting. With reference to the doctoral research of the first author, we argue for the relevance of using CMA for research into the maternity care setting, particularly as it relates to midwifery. We then give an overview of an existing analytic model within CMA that we adapted for looking specifically at childbirth practices and which was then used in both analyzing the data and structuring the thesis. There is often no clear guide to the analysis or writing up of data in ethnographic research; we therefore offer this Critical analytic model of childbirth practices for other researchers conducting ethnographic research into childbirth or maternity care.

  3. Single-ion hydration thermodynamics from clusters to bulk solutions: Recent insights from molecular modeling

    DOE PAGES

    Vlcek, Lukas; Chialvo, Ariel A.

    2016-01-03

    The importance of single-ion hydration thermodynamic properties for understanding the driving forces of aqueous electrolyte processes, along with the impossibility of their direct experimental measurement, have prompted a large number of experimental, theoretical, and computational studies aimed at separating the cation and anion contributions. Here we provide an overview of historical approaches based on extrathermodynamic assumptions and more recent computational studies of single-ion hydration in order to evaluate the approximations involved in these methods, quantify their accuracy, reliability, and limitations in the light of the latest developments. Finally, we also offer new insights into the factors that influence the accuracymore » of ion–water interaction models and our views on possible ways to fill this substantial knowledge gap in aqueous physical chemistry.« less

  4. Overview of the Brooklyn traffic real-time ambient pollutant penetration and environmental dispersion (B-TRAPPED) study: theoretical background and model for design of field experiments.

    PubMed

    Hahn, Intaek; Wiener, Russell W; Richmond-Bryant, Jennifer; Brixey, Laurie A; Henkle, Stacy W

    2009-12-01

    The Brooklyn traffic real-time ambient pollutant penetration and environmental dispersion (B-TRAPPED) study was a multidisciplinary field research project that investigated the transport, dispersion, and infiltration processes of traffic emission particulate matter (PM) pollutants in a near-highway urban residential area. The urban PM transport, dispersion, and infiltration processes were described mathematically in a theoretical model that was constructed to develop the experimental objectives of the B-TRAPPED study. In the study, simultaneous and continuous time-series PM concentration and meteorological data collected at multiple outdoor and indoor monitoring locations were used to characterize both temporal and spatial patterns of the PM concentration movements within microscale distances (<500 m) from the highway. Objectives of the study included (1) characterizing the temporal and spatial PM concentration fluctuation and distribution patterns in the urban street canyon; (2) investigating the effects of urban structures such as a tall building or an intersection on the transport and dispersion of PM; (3) studying the influence of meteorological variables on the transport, dispersion, and infiltration processes; (4) characterizing the relationships between the building parameters and the infiltration mechanisms; (5) establishing a cause-and-effect relationship between outdoor-released PM and indoor PM concentrations and identifying the dominant mechanisms involved in the infiltration process; (6) evaluating the effectiveness of a shelter-in-place area for protection against outdoor-released PM pollutants; and (7) understanding the predominant airflow and pollutant dispersion patterns within the neighborhood using wind tunnel and CFD simulations. The 10 papers in this first set of papers presenting the results from the B-TRAPPED study address these objectives. This paper describes the theoretical background and models representing the interrelated processes of transport, dispersion, and infiltration. The theoretical solution for the relationship between the time-dependent indoor PM concentration and the initial PM concentration at the outdoor source was obtained. The theoretical models and solutions helped us to identify important parameters in the processes of transport, dispersion, and infiltration. The B-TRAPPED study field experiments were then designed to investigate these parameters in the hope of better understanding urban PM pollutant behaviors.

  5. Recent modelling advances for ultrasonic TOFD inspections

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

    Darmon, Michel; Ferrand, Adrien; Dorval, Vincent

    The ultrasonic TOFD (Time of Flight Diffraction) Technique is commonly used to detect and characterize disoriented cracks using their edge diffraction echoes. An overview of the models integrated in the CIVA software platform and devoted to TOFD simulation is presented. CIVA allows to predict diffraction echoes from complex 3D flaws using a PTD (Physical Theory of Diffraction) based model. Other dedicated developments have been added to simulate lateral waves in 3D on planar entry surfaces and in 2D on irregular surfaces by a ray approach. Calibration echoes from Side Drilled Holes (SDHs), specimen echoes and shadowing effects from flaws canmore » also been modelled. Some examples of theoretical validation of the models are presented. In addition, experimental validations have been performed both on planar blocks containing calibration holes and various notches and also on a specimen with an irregular entry surface and allow to draw conclusions on the validity of all the developed models.« less

  6. Synthesis meets theory: Past, present and future of rational chemistry

    NASA Astrophysics Data System (ADS)

    Fianchini, Mauro

    2017-11-01

    Chemical synthesis has its roots in the empirical approach of alchemy. Nonetheless, the birth of the scientific method, the technical and technological advances (exploiting revolutionary discoveries in physics) and the improved management and sharing of growing databases greatly contributed to the evolution of chemistry from an esoteric ground into a mature scientific discipline during these last 400 years. Furthermore, thanks to the evolution of computational resources, platforms and media in the last 40 years, theoretical chemistry has added to the puzzle the final missing tile in the process of "rationalizing" chemistry. The use of mathematical models of chemical properties, behaviors and reactivities is nowadays ubiquitous in literature. Theoretical chemistry has been successful in the difficult task of complementing and explaining synthetic results and providing rigorous insights when these are otherwise unattainable by experiment. The first part of this review walks the reader through a concise historical overview on the evolution of the "model" in chemistry. Salient milestones have been highlighted and briefly discussed. The second part focuses more on the general description of recent state-of-the-art computational techniques currently used worldwide by chemists to produce synergistic models between theory and experiment. Each section is complemented by key-examples taken from the literature that illustrate the application of the technique discussed therein.

  7. Healthy Eating Strategies in the Workplace

    PubMed Central

    Quintiliani, Lisa; Poulsen, Signe; Sorensen, Glorian

    2013-01-01

    Purpose There is a clear link between dietary behavior and a range of chronic diseases, and overweight and obesity constitute an indirect risk in relation to these diseases. The worksite is a central venue for influencing dietary behavior. The purpose of this paper is to provide an overview of workplace influences on worker dietary patterns. Design/methodology/approach The paper reviews the evidence of the effectiveness of dietary health promotion, and provides a brief overview of appropriate theoretical frameworks to guide intervention design and evaluation. The findings are illustrated through research examples. Findings Through case studies and published research, it is found that workplace dietary interventions are generally effective, especially fruit and vegetable interventions. There is less consistent evidence on the long term effectiveness of workplace weight management interventions, underscoring the need for further research in this area. This paper also reports evidence that changes in the work environment, including through health and safety programs, may contribute to enhancing the effectiveness of workplace health promotion, including dietary interventions. Organizational factors such as work schedule may also influence dietary patterns. The social ecological model, the social contextual model and political process approach are presented as exemplar conceptual models that may be useful when designing or assessing the effects of workplace health promotion. Originality/value Using the worksite as setting for influencing health by influencing dietary patterns holds considerable promise and may be instrumental in reducing workers’ risk of chronic diseases. PMID:23935706

  8. Disaster Planning in Libraries

    ERIC Educational Resources Information Center

    Wong, Yi Ling; Green, Ravonne

    2006-01-01

    Disaster preparedness is an important issue in library management today. This article presents a general overview of the theoretical aspects of disaster planning in libraries. The stages of disaster planning are a circular process of planning, prevention, response, recovery, preparedness, and training.

  9. Executive Coaching Practices in the Adult Workplace

    ERIC Educational Resources Information Center

    Campone, Francine

    2015-01-01

    This chapter provides an overview of key principles and practices in executive coaching. Coaching is discussed as a reflective learning opportunity and offers the theoretical grounding, strategies, and case studies for each of four key elements of a coaching engagement.

  10. Modeling Supernova Shocks with Intense Lasers.

    NASA Astrophysics Data System (ADS)

    Blue, Brent

    2006-04-01

    Large-scale directional outflows of supersonic plasma are ubiquitous phenomena in astrophysics, with specific application to supernovae. The traditional approach to understanding such phenomena is through theoretical analysis and numerical simulations. However, theoretical analysis might not capture all the relevant physics and numerical simulations have limited resolution and fail to scale correctly in Reynolds number and perhaps other key dimensionless parameters. Recent advances in high energy density physics using large inertial confinement fusion devices now allow controlled laboratory experiments on macroscopic volumes of plasma of direct relevance to astrophysics. This talk will present an overview of these facilities as well as results from current laboratory astrophysics experiments designed to study hydrodynamic jets and Rayleigh-Taylor mixing. This work is performed under the auspices of the U. S. DOE by Lawrence Livermore National Laboratory under Contract No. W-7405-ENG-48, Los Alamos National Laboratory under Contract No. W-7405-ENG-36, and the Laboratory for Laser Energetics under Contract No. DE-FC03-92SF19460.

  11. The French connection: some contributions of French-language research in the post-Piagetian era.

    PubMed

    Larivée, S; Normandeau, S; Parent, S

    2000-01-01

    This article presents French-speaking researchers' contribution to the field of differential developmental psychology. Following a brief review of key Piagetian ideas pertaining to his conceptualization of individual differences, the core of the article traces methodological and theoretical transformations that were necessary for understanding individual differences within a general theory of cognitive development. On a methodological level, French-speaking researchers went from standardizing Piaget's clinical method to constructing developmental scales and operational tests. On a theoretical level, Reuchlin's writings guided Longeot, and several other French (Lautrey and Bideaud) and Genevan (de Ribaupierre and Rieben) researchers into a scientific quest for a genuine integration of differential and developmental psychology. We present an overview of the pluralistic and multidimensional model of cognitive functioning and development that emerged from the work of the French-Swiss team of researchers. Concluding remarks focus on the actual research agendas of researchers interested in resolving the challenging issue of understanding relationships between inter- and intraindividual differences and general tendencies in cognitive development.

  12. Single-polymer dynamics under constraints: scaling theory and computer experiment.

    PubMed

    Milchev, Andrey

    2011-03-16

    The relaxation, diffusion and translocation dynamics of single linear polymer chains in confinement is briefly reviewed with emphasis on the comparison between theoretical scaling predictions and observations from experiment or, most frequently, from computer simulations. Besides cylindrical, spherical and slit-like constraints, related problems such as the chain dynamics in a random medium and the translocation dynamics through a nanopore are also considered. Another particular kind of confinement is imposed by polymer adsorption on attractive surfaces or selective interfaces--a short overview of single-chain dynamics is also contained in this survey. While both theory and numerical experiments consider predominantly coarse-grained models of self-avoiding linear chain molecules with typically Rouse dynamics, we also note some recent studies which examine the impact of hydrodynamic interactions on polymer dynamics in confinement. In all of the aforementioned cases we focus mainly on the consequences of imposed geometric restrictions on single-chain dynamics and try to check our degree of understanding by assessing the agreement between theoretical predictions and observations.

  13. Quantifying Reinforcement Value and Demand for Psychoactive Substances in Humans

    PubMed Central

    Heinz, Adrienne J.; Lilje, Todd C.; Kassel, Jon D.; de Wit, Harriet

    2013-01-01

    Behavioral economics is an emerging cross-disciplinary field that is providing an exciting new contextual framework for researchers to study addictive processes. New initiatives to study addiction under a behavioral economic rubric have yielded variable terminology and differing methods and theoretical approaches that are consistent with the multidimensional nature of addiction. The present article is intended to provide an integrative overview of the behavioral economic nomenclature and to describe relevant theoretical models, principles and concepts. Additionally, we present measures derived from behavioral economic theories that quantify demand for substances and assess decision making processes surrounding substance use. The sensitivity of these measures to different contextual elements (e.g., drug use status, acute drug effects, deprivation) is also addressed. The review concludes with discussion of the validity of these approaches and their potential for clinical application and highlights areas that warrant further research. Overall, behavioral economics offers a compelling framework to help explicate complex addictive processes and it is likely to provide a translational platform for clinical intervention. PMID:23062106

  14. Acceptability of healthcare interventions: an overview of reviews and development of a theoretical framework.

    PubMed

    Sekhon, Mandeep; Cartwright, Martin; Francis, Jill J

    2017-01-26

    It is increasingly acknowledged that 'acceptability' should be considered when designing, evaluating and implementing healthcare interventions. However, the published literature offers little guidance on how to define or assess acceptability. The purpose of this study was to develop a multi-construct theoretical framework of acceptability of healthcare interventions that can be applied to assess prospective (i.e. anticipated) and retrospective (i.e. experienced) acceptability from the perspective of intervention delivers and recipients. Two methods were used to select the component constructs of acceptability. 1) An overview of reviews was conducted to identify systematic reviews that claim to define, theorise or measure acceptability of healthcare interventions. 2) Principles of inductive and deductive reasoning were applied to theorise the concept of acceptability and develop a theoretical framework. Steps included (1) defining acceptability; (2) describing its properties and scope and (3) identifying component constructs and empirical indicators. From the 43 reviews included in the overview, none explicitly theorised or defined acceptability. Measures used to assess acceptability focused on behaviour (e.g. dropout rates) (23 reviews), affect (i.e. feelings) (5 reviews), cognition (i.e. perceptions) (7 reviews) or a combination of these (8 reviews). From the methods described above we propose a definition: Acceptability is a multi-faceted construct that reflects the extent to which people delivering or receiving a healthcare intervention consider it to be appropriate, based on anticipated or experienced cognitive and emotional responses to the intervention. The theoretical framework of acceptability (TFA) consists of seven component constructs: affective attitude, burden, perceived effectiveness, ethicality, intervention coherence, opportunity costs, and self-efficacy. Despite frequent claims that healthcare interventions have assessed acceptability, it is evident that acceptability research could be more robust. The proposed definition of acceptability and the TFA can inform assessment tools and evaluations of the acceptability of new or existing interventions.

  15. Host-pathogen interactions between the human innate immune system and Candida albicans—understanding and modeling defense and evasion strategies

    PubMed Central

    Dühring, Sybille; Germerodt, Sebastian; Skerka, Christine; Zipfel, Peter F.; Dandekar, Thomas; Schuster, Stefan

    2015-01-01

    The diploid, polymorphic yeast Candida albicans is one of the most important human pathogenic fungi. C. albicans can grow, proliferate and coexist as a commensal on or within the human host for a long time. However, alterations in the host environment can render C. albicans virulent. In this review, we describe the immunological cross-talk between C. albicans and the human innate immune system. We give an overview in form of pairs of human defense strategies including immunological mechanisms as well as general stressors such as nutrient limitation, pH, fever etc. and the corresponding fungal response and evasion mechanisms. Furthermore, Computational Systems Biology approaches to model and investigate these complex interactions are highlighted with a special focus on game-theoretical methods and agent-based models. An outlook on interesting questions to be tackled by Systems Biology regarding entangled defense and evasion mechanisms is given. PMID:26175718

  16. In pursuit of an accurate spatial and temporal model of biomolecules at the atomistic level: a perspective on computer simulation.

    PubMed

    Gray, Alan; Harlen, Oliver G; Harris, Sarah A; Khalid, Syma; Leung, Yuk Ming; Lonsdale, Richard; Mulholland, Adrian J; Pearson, Arwen R; Read, Daniel J; Richardson, Robin A

    2015-01-01

    Despite huge advances in the computational techniques available for simulating biomolecules at the quantum-mechanical, atomistic and coarse-grained levels, there is still a widespread perception amongst the experimental community that these calculations are highly specialist and are not generally applicable by researchers outside the theoretical community. In this article, the successes and limitations of biomolecular simulation and the further developments that are likely in the near future are discussed. A brief overview is also provided of the experimental biophysical methods that are commonly used to probe biomolecular structure and dynamics, and the accuracy of the information that can be obtained from each is compared with that from modelling. It is concluded that progress towards an accurate spatial and temporal model of biomacromolecules requires a combination of all of these biophysical techniques, both experimental and computational.

  17. Understanding the oriented-attachment growth of nanocrystals from an energy point of view: a review

    NASA Astrophysics Data System (ADS)

    Lv, Weiqiang; He, Weidong; Wang, Xiaoning; Niu, Yinghua; Cao, Huanqi; Dickerson, James H.; Wang, Zhiguo

    2014-02-01

    Since Penn et al. first discovered the oriented attachment growth of crystals, the oriented attachment mechanism has now become a major research focus in the crystal field, and extensive efforts have been carried out over the past decade to systematically investigate the growth mechanism and the statistical kinetic models. However, most of the work mainly focuses on the experimental results on the oriented attachment growth. In contrast to the previous reviews, our review provides an overview of the recent theoretical advances in oriented attachment kinetics combined with experimental evidences. After a brief introduction to the van der Waals interaction and Coulombic interaction in a colloidal system, the correlation between the kinetic models of oriented attachment growth and the interactions is then our focus. The impact of in situ experimental observation techniques on the study of oriented attachment growth is examined with insightful examples. In addition, the advances in theoretical simulations mainly investigating the thermodynamic origin of these interactions at the atomic level are reviewed. This review seeks to understand the oriented attachment crystal growth from a kinetic point of view and provide a quantitative methodology to rationally design an oriented attachment system with pre-evaluated crystal growth parameters.

  18. Neutron scattering studies of the RENi 2B 2C (RE = Lu, Y, Ho, Er): Lattice dynamics

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

    Bullock, Max

    1998-02-23

    The first chapter gives a brief overview of the system discussed in this dissertation. Chapters 2-5 and Appendix B of this dissertation consist of papers that are published, or have been submitted, which show experimental data regarding the phonon softening of LuNi 2B 2C. These papers have been removed and processed separately. Chapter 6 will contain a summary of the conclusions up to date. Appendix A will consist of a brief derivation of χ(q) which is talked about in the introduction of the dissertation. Appendix B will contain a Born-von Karman model fit to the experimental LuNi 2B 2C datamore » and a comparison with experimental data. Appendix C will contain a brief summary of the work done on LuNi 2B 2C as well as a complete listing of experimental data taken on the crystals which may be needed later for theoretical models of this system. Appendix D will outline a brief introduction covering some of the field theory used in the theoretical work for this thesis.« less

  19. Computational Science in Armenia (Invited Talk)

    NASA Astrophysics Data System (ADS)

    Marandjian, H.; Shoukourian, Yu.

    This survey is devoted to the development of informatics and computer science in Armenia. The results in theoretical computer science (algebraic models, solutions to systems of general form recursive equations, the methods of coding theory, pattern recognition and image processing), constitute the theoretical basis for developing problem-solving-oriented environments. As examples can be mentioned: a synthesizer of optimized distributed recursive programs, software tools for cluster-oriented implementations of two-dimensional cellular automata, a grid-aware web interface with advanced service trading for linear algebra calculations. In the direction of solving scientific problems that require high-performance computing resources, examples of completed projects include the field of physics (parallel computing of complex quantum systems), astrophysics (Armenian virtual laboratory), biology (molecular dynamics study of human red blood cell membrane), meteorology (implementing and evaluating the Weather Research and Forecast Model for the territory of Armenia). The overview also notes that the Institute for Informatics and Automation Problems of the National Academy of Sciences of Armenia has established a scientific and educational infrastructure, uniting computing clusters of scientific and educational institutions of the country and provides the scientific community with access to local and international computational resources, that is a strong support for computational science in Armenia.

  20. Physics of the Kitaev Model: Fractionalization, Dynamic Correlations, and Material Connections

    NASA Astrophysics Data System (ADS)

    Hermanns, M.; Kimchi, I.; Knolle, J.

    2018-03-01

    Quantum spin liquids have fascinated condensed matter physicists for decades because of their unusual properties such as spin fractionalization and long-range entanglement. Unlike conventional symmetry breaking, the topological order underlying quantum spin liquids is hard to detect experimentally. Even theoretical models are scarce for which the ground state is established to be a quantum spin liquid. The Kitaev honeycomb model and its generalizations to other tricoordinated lattices are chief counterexamples - they are exactly solvable, harbor a variety of quantum spin liquid phases, and are also relevant for certain transition metal compounds including the polymorphs of (Na,Li)2IrO3 iridates and RuCl3. In this review, we give an overview of the rich physics of the Kitaev model, including two-dimensional and three-dimensional fractionalization as well as dynamic correlations and behavior at finite temperatures. We discuss the different materials and argue how the Kitaev model physics can be relevant even though most materials show magnetic ordering at low temperatures.

  1. Control of automated behavior: insights from the discrete sequence production task

    PubMed Central

    Abrahamse, Elger L.; Ruitenberg, Marit F. L.; de Kleine, Elian; Verwey, Willem B.

    2013-01-01

    Work with the discrete sequence production (DSP) task has provided a substantial literature on discrete sequencing skill over the last decades. The purpose of the current article is to provide a comprehensive overview of this literature and of the theoretical progress that it has prompted. We start with a description of the DSP task and the phenomena that are typically observed with it. Then we propose a cognitive model, the dual processor model (DPM), which explains performance of (skilled) discrete key-press sequences. Key features of this model are the distinction between a cognitive processor and a motor system (i.e., motor buffer and motor processor), the interplay between these two processing systems, and the possibility to execute familiar sequences in two different execution modes. We further discuss how this model relates to several related sequence skill research paradigms and models, and we outline outstanding questions for future research throughout the paper. We conclude by sketching a tentative neural implementation of the DPM. PMID:23515430

  2. Hyperbolic scaling and computing in social crowds: Comment on "Human behaviours in evacuation crowd dynamics: From modelling to "big data" toward crisis management" by Nicola Bellomo et al.

    NASA Astrophysics Data System (ADS)

    Outada, Nisrine

    2016-09-01

    I have read with great interest the paper [5] where the authors present an overview and critical analysis of the literature on the modeling of the crowd dynamics with special attention to evacuation dynamics. The approach developed is based on suitable development of methods of the kinetic theory. Interactions, which lead to the decision choice, are modeled by theoretical tools of stochastic evolutionary game theory [11,12]. However, the paper [5] provides not only a survey focused on topics of great interest for our society, but also it looks ahead to a variety of interesting and challenging mathematical problems. Specifically, I am interested in the derivation of macroscopic (hydrodynamic) models from the underlying description given from the kinetic theory approach, more specifically by the kinetic theory for active particles [8]. A general reference on crowd modeling is the recently published book [10].

  3. Bayesian inference for psychology, part IV: parameter estimation and Bayes factors.

    PubMed

    Rouder, Jeffrey N; Haaf, Julia M; Vandekerckhove, Joachim

    2018-02-01

    In the psychological literature, there are two seemingly different approaches to inference: that from estimation of posterior intervals and that from Bayes factors. We provide an overview of each method and show that a salient difference is the choice of models. The two approaches as commonly practiced can be unified with a certain model specification, now popular in the statistics literature, called spike-and-slab priors. A spike-and-slab prior is a mixture of a null model, the spike, with an effect model, the slab. The estimate of the effect size here is a function of the Bayes factor, showing that estimation and model comparison can be unified. The salient difference is that common Bayes factor approaches provide for privileged consideration of theoretically useful parameter values, such as the value corresponding to the null hypothesis, while estimation approaches do not. Both approaches, either privileging the null or not, are useful depending on the goals of the analyst.

  4. NASA Iced Aerodynamics and Controls Current Research

    NASA Technical Reports Server (NTRS)

    Addy, Gene

    2009-01-01

    This slide presentation reviews the state of current research in the area of aerodynamics and aircraft control with ice conditions by the Aviation Safety Program, part of the Integrated Resilient Aircraft Controls Project (IRAC). Included in the presentation is a overview of the modeling efforts. The objective of the modeling is to develop experimental and computational methods to model and predict aircraft response during adverse flight conditions, including icing. The Aircraft icing modeling efforts includes the Ice-Contaminated Aerodynamics Modeling, which examines the effects of ice contamination on aircraft aerodynamics, and CFD modeling of ice-contaminated aircraft aerodynamics, and Advanced Ice Accretion Process Modeling which examines the physics of ice accretion, and works on computational modeling of ice accretions. The IRAC testbed, a Generic Transport Model (GTM) and its use in the investigation of the effects of icing on its aerodynamics is also reviewed. This has led to a more thorough understanding and models, both theoretical and empirical of icing physics and ice accretion for airframes, advanced 3D ice accretion prediction codes, CFD methods for iced aerodynamics and better understanding of aircraft iced aerodynamics and its effects on control surface effectiveness.

  5. Stochastic simulation in systems biology

    PubMed Central

    Székely, Tamás; Burrage, Kevin

    2014-01-01

    Natural systems are, almost by definition, heterogeneous: this can be either a boon or an obstacle to be overcome, depending on the situation. Traditionally, when constructing mathematical models of these systems, heterogeneity has typically been ignored, despite its critical role. However, in recent years, stochastic computational methods have become commonplace in science. They are able to appropriately account for heterogeneity; indeed, they are based around the premise that systems inherently contain at least one source of heterogeneity (namely, intrinsic heterogeneity). In this mini-review, we give a brief introduction to theoretical modelling and simulation in systems biology and discuss the three different sources of heterogeneity in natural systems. Our main topic is an overview of stochastic simulation methods in systems biology. There are many different types of stochastic methods. We focus on one group that has become especially popular in systems biology, biochemistry, chemistry and physics. These discrete-state stochastic methods do not follow individuals over time; rather they track only total populations. They also assume that the volume of interest is spatially homogeneous. We give an overview of these methods, with a discussion of the advantages and disadvantages of each, and suggest when each is more appropriate to use. We also include references to software implementations of them, so that beginners can quickly start using stochastic methods for practical problems of interest. PMID:25505503

  6. Wilderness Therapy: Foundations, Theory and Research.

    ERIC Educational Resources Information Center

    Davis-Berman, Jennifer; Berman, Dene S.

    This book provides an overview of the history, theoretical basis, research, development, evaluation, and current status of wilderness therapy programs for troubled adolescents. An introduction explores theories of adolescence and adolescent development, problems facing adolescents in contemporary society, limitations of traditional mental health…

  7. Theories of Occupational Segregation by Sex: An Overview.

    ERIC Educational Resources Information Center

    Anker, Richard

    1997-01-01

    Reviews theoretical explanations for gender segregation in occupations: neoclassical, human capital, institutional and labor market segmentation, and gender discrimination. Determines that gender discrimination theories are most compelling, given the enormous overlap in abilities and preferences of individual men and women. (SK)

  8. Theory overview of tree-level B decays

    NASA Astrophysics Data System (ADS)

    De Fazio, F.

    2017-07-01

    I describe the theoretical progress in the study of semileptonic tree-level B decays, and its interplay with recent experimental results. In particular, I focus on two anomalies: the ratios $R(D^{(*)})=\\displaystyle\\frac{{\\cal B}(B \\to D^{(*)} \\tau \\bar \

  9. Transpersonalism: Ego Meets Soul.

    ERIC Educational Resources Information Center

    Strohl, James E.

    1998-01-01

    The transpersonal approach has emerged from mainstream psychology to address the effects of spirituality and consciousness on personal transformation and health, and to explore optimal levels of human functioning. This article provides an overview of the historical development, scientific basis, philosophical stance, theoretical principles, and…

  10. Definition of a visuospatial dimension as a step forward in the diagnostic puzzle of nonverbal learning disability.

    PubMed

    Poletti, Michele

    2017-01-01

    Although clinically recognized for almost 50 years, the categorical distinction of specific learning disabilities due to an impairment of the nonverbal domain (nonverbal learning disability [NLD]) is still debated and controversial. Unsolved issues involve theoretical models, diagnostic criteria, rehabilitative interventions, and moderator factors. These issues are briefly overviewed to sustain the need for a shift toward dimensional approaches, as suggested by research domain criteria, as a step forward in the diagnostic puzzle of NLD. With this aim, a visuospatial dimension, or spectrum, is proposed, and then clinical conditions that may fit with its impaired side are systemized, while specifying in which conditions a visuospatial impairment may be considered an NLD.

  11. Array Simulations Platform (ASP) predicts NASA Data Link Module (NDLM) performance

    NASA Technical Reports Server (NTRS)

    Snook, Allen David

    1993-01-01

    Through a variety of imbedded theoretical and actual antenna patterns, the array simulation platform (ASP) enhanced analysis of the array antenna pattern effects for the KTx (Ku-Band Transmit) service of the NDLM (NASA Data Link Module). The ASP utilizes internally stored models of the NDLM antennas and can develop the overall pattern of antenna arrays through common array calculation techniques. ASP expertly assisted in the diagnosing of element phase shifter errors during KTx testing and was able to accurately predict the overall array pattern from combinations of the four internally held element patterns. This paper provides an overview of the use of the ASP software in the solving of array mis-phasing problems.

  12. Locating and characterizing a crack in concrete with diffuse ultrasound: A four-point bending test.

    PubMed

    Larose, Eric; Obermann, Anne; Digulescu, Angela; Planès, Thomas; Chaix, Jean-Francois; Mazerolle, Frédéric; Moreau, Gautier

    2015-07-01

    This paper describes an original imaging technique, named Locadiff, that benefits from the diffuse effect of ultrasound waves in concrete to detect and locate mechanical changes associated with the opening of pre-existing cracks, and/or to the development of diffuse damage at the tip of the crack. After giving a brief overview of the theoretical model to describe the decorrelation of diffuse waveforms induced by a local change, the article introduces the inversion procedure that produces the three dimensional maps of density of changes. These maps are interpreted in terms of mechanical changes, fracture opening, and damage development. In addition, each fracture is characterized by its effective scattering cross section.

  13. Dynamics of quantum turbulence of different spectra

    PubMed Central

    Walmsley, Paul; Zmeev, Dmitry; Pakpour, Fatemeh; Golov, Andrei

    2014-01-01

    Turbulence in a superfluid in the zero-temperature limit consists of a dynamic tangle of quantized vortex filaments. Different types of turbulence are possible depending on the level of correlations in the orientation of vortex lines. We provide an overview of turbulence in superfluid 4He with a particular focus on recent experiments probing the decay of turbulence in the zero-temperature regime below 0.5 K. We describe extensive measurements of the vortex line density during the free decay of different types of turbulence: ultraquantum and quasiclassical turbulence in both stationary and rotating containers. The observed decays and the effective dissipation as a function of temperature are compared with theoretical models and numerical simulations. PMID:24704876

  14. Environmental noise spectroscopy with qubits subjected to dynamical decoupling

    NASA Astrophysics Data System (ADS)

    Szańkowski, P.; Ramon, G.; Krzywda, J.; Kwiatkowski, D.; Cywiński, Ł.

    2017-08-01

    A qubit subjected to pure dephasing due to classical Gaussian noise can be turned into a spectrometer of this noise by utilizing its readout under properly chosen dynamical decoupling (DD) sequences to reconstruct the power spectral density of the noise. We review the theory behind this DD-based noise spectroscopy technique, paying special attention to issues that arise when the environmental noise is non-Gaussian and/or it has truly quantum properties. While we focus on the theoretical basis of the method, we connect the discussed concepts with specific experiments, and provide an overview of environmental noise models relevant for solid-state based qubits, including quantum-dot based spin qubits, superconducting qubits, and NV centers in diamond.

  15. Quantum cryptography: Theoretical protocols for quantum key distribution and tests of selected commercial QKD systems in commercial fiber networks

    NASA Astrophysics Data System (ADS)

    Jacak, Monika; Jacak, Janusz; Jóźwiak, Piotr; Jóźwiak, Ireneusz

    2016-06-01

    The overview of the current status of quantum cryptography is given in regard to quantum key distribution (QKD) protocols, implemented both on nonentangled and entangled flying qubits. Two commercial R&D platforms of QKD systems are described (the Clavis II platform by idQuantique implemented on nonentangled photons and the EPR S405 Quelle platform by AIT based on entangled photons) and tested for feasibility of their usage in commercial TELECOM fiber metropolitan networks. The comparison of systems efficiency, stability and resistivity against noise and hacker attacks is given with some suggestion toward system improvement, along with assessment of two models of QKD.

  16. Different perspectives on the sex-attachment link: towards an emotion-motivational account.

    PubMed

    Dewitte, Marieke

    2012-01-01

    Although the link between sex and attachment was made decades ago (Hazan & Shaver, 1987), theories on sexual and attachment functioning have been developed in relative isolation. Recent efforts to integrate both literatures have been complicated by the fact that the sex-attachment link has been approached from very different perspectives, including biological, evolutionary, developmental, cognitive, and social psychology approaches. Also, at the empirical level, research on sex and attachment lacks overarching synthesis. This article gives an overview of the most important theoretical ideas and empirical insights on sex and attachment. It starts with describing general models that approach the sex-attachment link from an evolutionary and neurobiological perspective. Then, it summarizes theoretical and empirical ideas of attachment theory and describes how attachment style differences are manifested in intimate and sexual relationships. Research so far has been limited to studying the predicted link between sex and attachment in terms of broad descriptives, and it would benefit the literature to specify the processes and pathways that mediate the sex-attachment link. After a short discussion of the functional similarities between the sexual and the attachment systems, the article describes some specific--dynamical--models that focus on the emotional and cognitive-motivational processes through which attachment schemas influence sexual experiences. Such an emotion-motivational perspective on sex and attachment can help to organize theoretical ideas and empirical findings and eventually promote an integrative view on how attachment dynamics can interact with sexual experiences.

  17. SEISMIC DIAGNOSTICS OF RED GIANTS: FIRST COMPARISON WITH STELLAR MODELS

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

    Montalban, J.; Miglio, A.; Noels, A.

    2010-10-01

    The clear detection with CoRoT and KEPLER of radial and non-radial solar-like oscillations in many red giants paves the way for seismic inferences on the structure of such stars. We present an overview of the properties of the adiabatic frequencies and frequency separations of radial and non-radial oscillation modes for an extended grid of models. We highlight how their detection allows a deeper insight into the internal structure and evolutionary state of red giants. In particular, we find that the properties of dipole modes constitute a promising seismic diagnostic tool of the evolutionary state of red giant stars. We comparemore » our theoretical predictions with the first 34 days of KEPLER data and predict the frequency diagram expected for red giants in the CoRoT exofield in the galactic center direction.« less

  18. An Overview of Human Figure Modeling for Army Aviation Systems

    DTIC Science & Technology

    2010-04-01

    An Overview of Human Figure Modeling for Army Aviation Systems by Jamison S. Hicks, David B. Durbin, and Richard W. Kozycki ARL-TR-5154...April 2010 An Overview of Human Figure Modeling for Army Aviation Systems Jamison S. Hicks, David B. Durbin, and Richard W. Kozycki...TYPE Final 3. DATES COVERED (From - To) May 2009–August 2009 4. TITLE AND SUBTITLE An Overview of Human Figure Modeling for Army Aviation Systems

  19. Beyond the Isogloss: Trends in Hispanic Dialectology.

    ERIC Educational Resources Information Center

    Lipski, John M.

    1989-01-01

    An overview of contemporary Hispanic dialectology, focusing on phonological phenomena, syntax, classification schemes, and bilingual communities, demonstrates that dialectology has long ceased to be the collection of innumerable surface deviations. It is suggested that dialectology is a theoretical discipline searching for universal principles to…

  20. Language, Gesture, and Space.

    ERIC Educational Resources Information Center

    Emmorey, Karen, Ed.; Reilly, Judy S., Ed.

    A collection of papers addresses a variety of issues regarding the nature and structure of sign language, gesture, and gesture systems. Articles include: "Theoretical Issues Relating Language, Gesture, and Space: An Overview" (Karen Emmorey, Judy S. Reilly); "Real, Surrogate, and Token Space: Grammatical Consequences in ASL American…

  1. Cognitive Architectures for Multimedia Learning

    ERIC Educational Resources Information Center

    Reed, Stephen K.

    2006-01-01

    This article provides a tutorial overview of cognitive architectures that can form a theoretical foundation for designing multimedia instruction. Cognitive architectures include a description of memory stores, memory codes, and cognitive operations. Architectures that are relevant to multimedia learning include Paivio's dual coding theory,…

  2. Cultural Diversity in the Workplace: The State of the Field.

    ERIC Educational Resources Information Center

    Fine, Marlene G.

    1996-01-01

    Reviews three broad categories of research on cultural diversity in the workplace: general overviews, theoretical perspectives, and empirical research studies. Offers an explanation for the paucity of research on the topic, and suggests topics and methods for future research. (SR)

  3. Ethnographic/Qualitative Research: Theoretical Perspectives and Methodological Strategies.

    ERIC Educational Resources Information Center

    Butler, E. Dean

    This paper examines the metatheoretical concepts associated with ethnographic/qualitative educational inquiry and overviews the more commonly utilized research designs, data collection methods, and analytical approaches. The epistemological and ontological assumptions of this newer approach differ greatly from those of the traditional educational…

  4. A Girl Is No Girl Is a Girl_: Girls-Work after Queer Theory

    ERIC Educational Resources Information Center

    Busche, Mart

    2013-01-01

    This contribution gives an overview over 40 years of girls-work in Germany. It highlights certain topics and theoretical implications and emphasises especially the realisation of queer theory and deconstructivism in the last 10 years. (Contains 4 notes.)

  5. An Overview of Conceptual Change Theories

    ERIC Educational Resources Information Center

    Özdemir, Gökhan; Clark, Douglas B.

    2007-01-01

    Conceptual change researchers have made significant progress on two prominent but competing theoretical perspectives regarding knowledge structure coherence. These perspectives can be broadly characterized as (1) knowledge-as-theory perspectives and (2) knowledge-as-elements perspectives. These perspectives can be briefly summarized in terms of…

  6. Does Pre-Assessment Work?

    ERIC Educational Resources Information Center

    Guskey, Thomas R.

    2018-01-01

    Exactly what is a pre-assessment, and how are they best used? In this article, Thomas R. Guskey explores the theoretical underpinnings of pre-assessments and provides an overview of the research. He also details the three forms that pre-assessments take: prerequisite, present, and preview.

  7. Aerodynamic Design of Axial Flow Compressors

    NASA Technical Reports Server (NTRS)

    Bullock, R. O. (Editor); Johnsen, I. A.

    1965-01-01

    An overview of 'Aerodynamic systems design of axial flow compressors' is presented. Numerous chapters cover topics such as compressor design, ptotential and viscous flow in two dimensional cascades, compressor stall and blade vibration, and compressor flow theory. Theoretical aspects of flow are also covered.

  8. Personality and self-regulation: trait and information-processing perspectives.

    PubMed

    Hoyle, Rick H

    2006-12-01

    This article introduces the special issue of Journal of Personality on personality and self-regulation. The goal of the issue is to illustrate and inspire research that integrates personality and process-oriented accounts of self-regulation. The article begins by discussing the trait perspective on self-regulation--distinguishing between temperament and personality accounts--and the information-processing perspective. Three approaches to integrating these perspectives are then presented. These range from methodological approaches, in which constructs representing the two perspectives are examined in integrated statistical models, to conceptual approaches, in which the two perspectives are unified in a holistic theoretical model of self-regulation. The article concludes with an overview of the special issue contributions, which are organized in four sections: broad, integrative models of personality and self-regulation; models that examine the developmental origins of self-regulation and self-regulatory styles; focused programs of research that concern specific aspects or applications of self-regulation; and strategies for increasing the efficiency and effectiveness of self-regulation.

  9. Challenges in modelling homogeneous catalysis: new answers from ab initio molecular dynamics to the controversy over the Wacker process.

    PubMed

    Stirling, András; Nair, Nisanth N; Lledós, Agustí; Ujaque, Gregori

    2014-07-21

    We present here a review of the mechanistic studies of the Wacker process stressing the long controversy about the key reaction steps. We give an overview of the previous experimental and theoretical studies on the topic. Then we describe the importance of the most recent Ab Initio Molecular Dynamics (AIMD) calculations in modelling organometallic reactivity in water. As a prototypical example of homogeneous catalytic reactions, the Wacker process poses serious challenges to modelling. The adequate description of the multiple role of the water solvent is very difficult by using static quantum chemical approaches including cluster and continuum solvent models. In contrast, such reaction systems are suitable for AIMD, and by combining with rare event sampling techniques, the method provides reaction mechanisms and the corresponding free energy profiles. The review also highlights how AIMD has helped to obtain a novel understanding of the mechanism and kinetics of the Wacker process.

  10. Educational Evaluation: Ethnography in Theory, Practice, and Politics.

    ERIC Educational Resources Information Center

    Fetterman, David M., Ed.; Pitman, Mary Anne, Ed.

    Ten essays on the use of ethnography in educational assessment are presented. Overview essays include: (1) "Beyond the Status Quo in Ethnographic Educational Evaluation" (David M. Fetterman) and (2) "The Ethnographic Evaluator" (David M. Fetterman). Theoretical papers include: (3) "Theory in Education Evaluation: Or,…

  11. Mainstreaming and the Minority Child.

    ERIC Educational Resources Information Center

    Jones, Reginald L., Ed.

    Provided are 16 author-contributed papers dealing with theoretical questions and practical concerns relating to the effect of mainstreaming on the minority child. The text is divided into five parts: overview and perspectives, educational assessment for mainstream placement, curriculum issues and teaching strategies, evaluation and research, and…

  12. Qualitative Career Assessment: An Overview and Analysis

    ERIC Educational Resources Information Center

    Whiston, Susan C.; Rahardja, Daryn

    2005-01-01

    Qualitative career assessments are theoretically based interventions that are grounded in constructivism. Constructivism is a departure from the traditional logical positive worldview that has influenced the development of many traditional career assessments. A central concept to constructivism is the importance of meaning, which can only be…

  13. The Politics of American Education

    ERIC Educational Resources Information Center

    Spring, Joel

    2010-01-01

    Turning his distinctive analytical lens to the politics of American education, the author looks at contemporary educational policy issues from theoretical, practical, and historical perspectives. This comprehensive overview documents and explains who influences educational policy and how, bringing to life the realities of schooling in the 21st…

  14. Sex Differences in Cognitive Abilities. Third Edition.

    ERIC Educational Resources Information Center

    Halpern, Diane F.

    This book examines the science and politics of cognitive sex differences, reflecting theories and research in the area over the past several years. Eight chapters discuss: (1) "Introduction and Overview" (e.g., theoretical approaches, values and science, and terminology); (2) "Searching for Sex Differences in Cognitive…

  15. Epilepsy: An Overview for the Special Educator.

    ERIC Educational Resources Information Center

    Nivens, Maryruth K.

    Intended to dispel myths concerning epilepsy, the paper discusses the history, symptoms and characteristics, possible causes and current medication approaches to the condition, theoretical assumptions are traced, and a definition explained. Charts depict the location of discharge; seizure patterns and accompanying physical/psychological symptoms;…

  16. High pressure effects on protein structure and function.

    PubMed

    Mozhaev, V V; Heremans, K; Frank, J; Masson, P; Balny, C

    1996-01-01

    Many biochemists would regard pressure as a physical parameter mainly of theoretical interest and of rather limited value in experimental biochemistry. The goal of this overview is to show that pressure is a powerful tool for the study of proteins and modulation of enzymatic activity.

  17. Integrating cognitive rehabilitation: A preliminary program description and theoretical review of an interdisciplinary cognitive rehabilitation program.

    PubMed

    Fleeman, Jennifer A; Stavisky, Christopher; Carson, Simon; Dukelow, Nancy; Maier, Sheryl; Coles, Heather; Wager, John; Rice, Jordyn; Essaff, David; Scherer, Marcia

    2015-01-01

    Interdisciplinary cognitive rehabilitation is emerging as the expected standard of care for individuals with mild to moderate degrees of cognitive impairment for a variety of etiologies. There is a growing body of evidence in cognitive rehabilitation literature supporting the involvement of multiple disciplines, with the use of cognitive support technologies (CSTs), in delivering cognitive therapy to individuals who require cognitive rehabilitative therapies. This article provides an overview of the guiding theories related to traditional approaches of cognitive rehabilitation and the positive impact of current theoretical models of an interdisciplinary approach in clinical service delivery of this rehabilitation. A theoretical model of the Integrative Cognitive Rehabilitation Program (ICRP) will be described in detail along with the practical substrates of delivering specific interventions to individuals and caregivers who are living with mild to moderate cognitive impairment. The ultimate goal of this article is to provide a clinically useful resource for direct service providers. It will serve to further clinical knowledge and understanding of the evolution from traditional silo based treatment paradigms to the current implementation of multiple perspectives and disciplines in the pursuit of patient centered care. The article will discuss the theories that contributed to the development of the interdisciplinary team and the ICRP model, implemented with individuals with mild to moderate cognitive deficits, regardless of etiology. The development and implementation of specific assessment and intervention strategies in this cognitive rehabilitation program will also be discussed. The assessment and intervention strategies utilized as part of ICRP are applicable to multiple clinical settings in which individuals with cognitive impairment are served. This article has specific implications for rehabilitation which include: (a) An Interdisciplinary Approach is an effective method for cognitive rehabilitation; and (b) Recent theories offer beneficial evaluation and intervention techniques for cognitive rehabilitation.

  18. Distant Healing Intention Therapies: An Overview of the Scientific Evidence

    PubMed Central

    Schlitz, Marilyn; Baur, Christopher

    2015-01-01

    This article provides a broad overview of “distant healing intention” (DHI) therapies, ie, intentional healing modalities claimed to transcend the usual constraints of distance through space or time. We provide a summary of previous reviews and meta-analyses that have explored a diverse array of DHI modalities, outcome measures, and experimental protocols. While some significant experimental effects have been observed, the evidence to date does not yet provide confidence in its clinical efficacy. The purported “nonlocal” nature of DHI raises significant methodological and theoretical challenges. We recommend several avenues for improving future research. PMID:26665044

  19. Medicaid payment policies for nursing home care: A national survey

    PubMed Central

    Buchanan, Robert J.; Madel, R. Peter; Persons, Dan

    1991-01-01

    This research gives a comprehensive overview of the nursing home payment methodologies used by each State Medicaid program. To present this comprehensive overview, 1988 data were collected by survey from 49 States and the District of Columbia. The literature was reviewed and integrated into the study to provide a theoretical framework to analyze the collected data. The data are organized and presented as follows: payment levels, payment methods, payment of capital-related costs, and incentives in nursing home payment. We conclude with a discussion of the impact these different methodologies have on program cost containment, quality, and recipient access. PMID:10114935

  20. Addition of Electrostatic Forces to EDEM with Applications to Triboelectrically Charged Particles

    NASA Technical Reports Server (NTRS)

    Hogue, Michael D.; Calle, Carlos; Curry, David

    2008-01-01

    Tribocharging of particles is common in many processes including fine powder handling and mixing, printer toner transport and dust extraction. In a lunar environment with its high vacuum and lack of water, electrostatic forces are an important factor to consider when designing and operating equipment. Dust mitigation and management is critical to safe and predictable performance of people and equipment. The extreme nature of lunar conditions makes it difficult and costly to carryout experiments on earth which are necessary to better understand how particles gather and transfer charge between each other and with equipment surfaces. DEM (Discrete Element Modeling) provides an excellent virtual laboratory for studying tribocharging of particles as well as for design of devices for dust mitigation and for other purposes related to handling and processing of lunar regolith. Theoretical and experimental work has been performed pursuant to incorporating screened Coulombic electrostatic forces into EDEM Tm, a commercial DEM software package. The DEM software is used to model the trajectories of large numbers of particles for industrial particulate handling and processing applications and can be coupled with other solvers and numerical models to calculate particle interaction with surrounding media and force fields. In this paper we will present overview of the theoretical calculations and experimental data and their comparison to the results of the DEM simulations. We will also discuss current plans to revise the DEM software with advanced electrodynamic and mechanical algorithms.

  1. Operational Space Weather in USAF Education

    NASA Astrophysics Data System (ADS)

    Smithtro, C.; Quigley, S.

    2006-12-01

    Most education programs offering space weather courses are understandably and traditionally heavily weighted with theoretical space physics that is the basis for most of what is researched and modeled. While understanding the theory is a good and necessary grounding for anyone working the field of space weather, few military or commercial jobs employ such theory in real-time operations. The operations sites/centers are much more geared toward use of applied theory-resultant models, tools and products. To ensure its operations centers personnel, commanders, real-time system operators and other customers affected by the space environment are educated on available and soon-to-be operational space weather models and products, the USAF has developed applicable course/lecture material taught at various institutions to include the Air Force Institute of Technology (AFIT) and the Joint Weather Training Complex (335th/TRS/OUA). Less frequent training of operational space weather is available via other venues that will be discussed, and associated course material is also being developed for potential use at the National Security Space Institute (NSSI). This presentation provides an overview of the programs, locations, courses and material developed and/or taught by or for USAF personnel dealing with operational space weather. It also provides general information on student research project results that may be used in operational support, along with observations regarding logistical and professional benefits of teaching such non-theoretical/non-traditional material.

  2. Strategic Planning for Computer-Based Educational Technology.

    ERIC Educational Resources Information Center

    Bozeman, William C.

    1984-01-01

    Offers educational practitioners direction for the development of a master plan for the implementation and application of computer-based educational technology by briefly examining computers in education, discussing organizational change from a theoretical perspective, and presenting an overview of the planning strategy known as the planning and…

  3. The Routledge International Handbook of Lifelong Learning

    ERIC Educational Resources Information Center

    Jarvis, Peter, Ed.

    2010-01-01

    As lifelong learning grows in popularity, few comprehensive pictures of the phenomenon have emerged. The "Routledge International Handbook of Lifelong Learning" provides a disciplined and complete overview of lifelong learning internationally. The theoretical structure puts the learner at the centre and the book emanates from there,…

  4. The Newtonian Mechanistic Paradigm, Special Education, and Contours of Alternatives: An Overview.

    ERIC Educational Resources Information Center

    Heshusius, Lous

    1989-01-01

    The article examines theoretical reorientations in special education away from the Newtonian mechanistic paradigm toward an emerging holistic paradigm. Recent literature is critiqued for renaming theories as paradigms, thereby providing an illusion of change while leaving fundamental mechanistic assumptions in place. (Author/DB)

  5. The Reparative Motive in Surrogate Mothers.

    ERIC Educational Resources Information Center

    Kanefield, Linda

    1999-01-01

    Explores the motivations of surrogate mothers, focusing on underlying reparative motive--to compensate for or repair an earlier loss or sense of damage. Provides an overview of the typical surrogate's characteristics and personality, discusses the theoretical underpinnings of the reparative motive, and considers the tension between reparation and…

  6. A Guide to Motivational Procedures for Instruction.

    ERIC Educational Resources Information Center

    Rubadeau, Duane O.; And Others

    Designed to provide community college instructors with an understanding of how to improve the motivational level of their students, this four-part guidebook reviews theoretical concepts and offers practical advice concerning student motivation and frustration. Section I provides an overview of both intrinsic and extrinsic motivation and of…

  7. Reconstructing Mathematics Pedagogy from a Constructivist Perspective.

    ERIC Educational Resources Information Center

    Simon, Martin A.

    1995-01-01

    Begins with an overview of the constructivist perspective and the pedagogical theory development upon which a constructivist teaching experiment with 20 prospective elementary teachers was based. Derives a theoretical framework for mathematics pedagogy with a focus on decisions about content and mathematical tasks. (49 references) (Author/DDD)

  8. Chinese Language Teaching and Information Technology.

    ERIC Educational Resources Information Center

    Ho, Man-koon

    2000-01-01

    Provides an overview of the theoretical arguments and problems encountered in the implementation of information technology in Chinese language teaching. States there is a belief that teaching and learning can be enhanced with the introduction of information technology, explaining that it may increase students' motivation to learn. (CMK)

  9. Frank Parsons on Interests

    ERIC Educational Resources Information Center

    Briddick, William C.

    2009-01-01

    In addition to Frank Parsons' posthumous publications a third manuscript remained unpublished. The manuscript can be classified as part of the success literature so prominent in Parsons' era. Within the manuscript is a chapter dealing with interests. Progress in recent years has further defined and provided a comprehensive theoretical overview of…

  10. Agronomic and environmental aspects of diazotrophic bacteria in irrigated rice fields

    USDA-ARS?s Scientific Manuscript database

    This article provides an overview of the free-living and plant-associated nitrogen-fixing bacterial communities in irrigated rice fields, with a focus on describing the drivers affecting community assemblages in this soil-water-plant-atmosphere system. Theoretical and technical advances in non-legu...

  11. Emotion and Emotion Regulation: From Another Perspective

    ERIC Educational Resources Information Center

    Langlois, Judith H.

    2004-01-01

    An overview of the content of the From Another Perspective collection on emotion and emotion regulation is provided. The lead article identifies fundamental issues of definition and the commentaries represent varying theoretical and methodological perspectives on emotion and emotion regulation. Together, the articles discuss the promises and…

  12. A Co-modeling Method Based on Component Features for Mechatronic Devices in Aero-engines

    NASA Astrophysics Data System (ADS)

    Wang, Bin; Zhao, Haocen; Ye, Zhifeng

    2017-08-01

    Data-fused and user-friendly design of aero-engine accessories is required because of their structural complexity and stringent reliability. This paper gives an overview of a typical aero-engine control system and the development process of key mechatronic devices used. Several essential aspects of modeling and simulation in the process are investigated. Considering the limitations of a single theoretic model, feature-based co-modeling methodology is suggested to satisfy the design requirements and compensate for diversity of component sub-models for these devices. As an example, a stepper motor controlled Fuel Metering Unit (FMU) is modeled in view of the component physical features using two different software tools. An interface is suggested to integrate the single discipline models into the synthesized one. Performance simulation of this device using the co-model and parameter optimization for its key components are discussed. Comparison between delivery testing and the simulation shows that the co-model for the FMU has a high accuracy and the absolute superiority over a single model. Together with its compatible interface with the engine mathematical model, the feature-based co-modeling methodology is proven to be an effective technical measure in the development process of the device.

  13. Urban science classrooms and new possibilities: on intersubjectivity and grammar in the third space

    NASA Astrophysics Data System (ADS)

    Emdin, Christopher

    2009-03-01

    In this article I explore research in urban science education inspired by the work of Kris Gutierrez in a paper based on her 2005 Scribner Award. It addresses key points in Gutierrez's work by exploring theoretical frameworks for research and approaches to teaching and research that expand the discourse on the agency of urban youth in corporate school settings. The work serves as an overview of under-discussed approaches and theoretical frameworks to consider in teaching and conducting research with marginalized urban youth in urban science classrooms.

  14. Lanthanide/Actinide Opacities

    NASA Astrophysics Data System (ADS)

    Hungerford, Aimee; Fontes, Christopher J.

    2018-06-01

    Gravitational wave observations benefit from accompanying electromagnetic signals in order to accurately determine the sky positions of the sources. The ejecta of neutron star mergers are expected to produce such electromagnetic transients, called macronovae (e.g. the recent and unprecedented observation of GW170817). Characteristics of the ejecta include large velocity gradients and the presence of heavy r-process elements, which pose significant challenges to the accurate calculation of radiative opacities and radiation transport. Opacities include a dense forest of bound-bound features arising from near-neutral lanthanide and actinide elements. Here we present an overview of current theoretical opacity determinations that are used by neutron star merger light curve modelers. We will touch on atomic physics and plasma modeling codes that are used to generate these opacities, as well as the limited body of laboratory experiments that may serve as points of validation for these complex atomic physics calculations.

  15. An ecological framework for sexual minority women's health: factors associated with greater body mass.

    PubMed

    Eliason, Michele J; Fogel, Sarah C

    2015-01-01

    In recent years, many studies have focused on the body of sexual minority women, particularly emphasizing their larger size. These studies rarely offer theoretically based explanations for the increased weight, nor study the potential consequences (or lack thereof) of being heavier. This article provides a brief overview of the multitude of factors that might cause or contribute to larger size of sexual minority women, using an ecological framework that elucidates upstream social determinants of health as well as individual risk factors. This model is infused with a minority stress model, which hypothesizes excess strain resulting from the stigma associated with oppressed minority identities such as woman, lesbian, bisexual, woman of color, and others. We argue that lack of attention to the upstream social determinants of health may result in individual-level victim blaming and interventions that do not address the root causes of minority stress or increased weight.

  16. Energy-level alignment at organic heterointerfaces

    PubMed Central

    Oehzelt, Martin; Akaike, Kouki; Koch, Norbert; Heimel, Georg

    2015-01-01

    Today’s champion organic (opto-)electronic devices comprise an ever-increasing number of different organic-semiconductor layers. The functionality of these complex heterostructures largely derives from the relative alignment of the frontier molecular-orbital energies in each layer with respect to those in all others. Despite the technological relevance of the energy-level alignment at organic heterointerfaces, and despite continued scientific interest, a reliable model that can quantitatively predict the full range of phenomena observed at such interfaces is notably absent. We identify the limitations of previous attempts to formulate such a model and highlight inconsistencies in the interpretation of the experimental data they were based on. We then develop a theoretical framework, which we demonstrate to accurately reproduce experiment. Applying this theory, a comprehensive overview of all possible energy-level alignment scenarios that can be encountered at organic heterojunctions is finally given. These results will help focus future efforts on developing functional organic interfaces for superior device performance. PMID:26702447

  17. Analysis of Market Opportunities for Chinese Private Express Delivery Industry

    NASA Astrophysics Data System (ADS)

    Jiang, Changbing; Bai, Lijun; Tong, Xiaoqing

    China's express delivery market has become the arena in which each express enterprise struggles to chase due to the huge potential demand and high profitable prospects. So certain qualitative and quantitative forecast for the future changes of China's express delivery market will help enterprises understand various types of market conditions and social changes in demand and adjust business activities to enhance their competitiveness timely. The development of China's express delivery industry is first introduced in this chapter. Then the theoretical basis of the regression model is overviewed. We also predict the demand trends of China's express delivery market by using Pearson correlation analysis and regression analysis from qualitative and quantitative aspects, respectively. Finally, we draw some conclusions and recommendations for China's express delivery industry.

  18. Collective animal navigation and migratory culture: from theoretical models to empirical evidence

    PubMed Central

    Dell, Anthony I.

    2018-01-01

    Animals often travel in groups, and their navigational decisions can be influenced by social interactions. Both theory and empirical observations suggest that such collective navigation can result in individuals improving their ability to find their way and could be one of the key benefits of sociality for these species. Here, we provide an overview of the potential mechanisms underlying collective navigation, review the known, and supposed, empirical evidence for such behaviour and highlight interesting directions for future research. We further explore how both social and collective learning during group navigation could lead to the accumulation of knowledge at the population level, resulting in the emergence of migratory culture. This article is part of the theme issue ‘Collective movement ecology’. PMID:29581394

  19. Pulse Detonation Rocket Engine Research at NASA Marshall

    NASA Technical Reports Server (NTRS)

    Morris, Christopher I.

    2003-01-01

    This viewgraph representation provides an overview of research being conducted on Pulse Detonation Rocket Engines (PDRE) by the Propulsion Research Center (PRC) at the Marshall Space Flight Center. PDREs have a theoretical thermodynamic advantage over Steady-State Rocket Engines (SSREs) although unsteady blowdown processes complicate effective use of this advantage in practice; PRE is engaged in a fundamental study of PDRE gas dynamics to improve understanding of performance issues. Topics covered include: simplified PDRE cycle, comparison of PDRE and SSRE performance, numerical modeling of quasi 1-D rocket flows, time-accurate thrust calculations, finite-rate chemistry effects in nozzles, effect of F-R chemistry on specific impulse, effect of F-R chemistry on exit species mole fractions and PDRE performance optimization studies.

  20. Planet Formation

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.; DeVincenzi, Donald L. (Technical Monitor)

    1998-01-01

    An overview of current theories of star and planet formation is presented. These models are based upon observations of the Solar System and of young stars and their environments. They predict that rocky planets should form around most single stars, although it is possible that in some cases such planets are lost to orbital decay within the protoplanetary disk. The frequency of formation of gas giant planets is more difficult to predict theoretically. Terrestrial planets are believed to grow via pairwise accretion until the spacing of planetary orbits becomes large enough that the configuration is stable for the age of the system. Giant planets begin their growth like terrestrial planets, but they become massive enough that they are able to accumulate substantial amounts of gas before the protoplanetary disk dissipates.

  1. Formation of Planetary Systems

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.; DeVincenzi, Donald (Technical Monitor)

    1999-01-01

    An overview of current theories of star and planet formation is presented. These models are based upon observations of the Solar System and of young stars and their environments. They predict that rocky planets should form around most single stars, although it is possible that in some cases such planets are lost to orbital decay within the protoplanetary disk. The frequency of formation of gas giant planets is more difficult to predict theoretically. Terrestrial planets are believed to grow via pairwise accretion until the spacing of planetary orbits becomes large enough that the configuration is stable for the age of the system. Giant planets begin their growth like terrestrial planets, but they become massive enough that they are able to accumulate substantial amounts of gas before the protoplanetary disk dissipates.

  2. The Birth of Planetary Systems

    NASA Technical Reports Server (NTRS)

    Lissaur, Jack L.

    1997-01-01

    An overview of current theories of star and planet formation is presented. These models are based upon observations of the Solar System and of young stars and their environments. They predict that rocky planets should form around most single stars, although it is possible that in some cases such planets are lost to orbital decay within the protoplanetary disk. The frequency of formation of gas giant planets is more difficult to predict theoretically. Terrestrial planets are believed to grow via pairwise accretion until the spacing of planetary orbits becomes large enough that the configuration is stable for the age of the system. Giant planets begin their growth like terrestrial planets, but they become massive enough that they are able to accumulate substantial amounts of gas before the protoplanetary disk dissipates.

  3. Using reflection time-of-flight mass spectrometer techniques to investigate cluster dynamics and bonding

    NASA Astrophysics Data System (ADS)

    Wei, Shiqing; Castleman, A. W., Jr.

    1994-02-01

    Lase based time-of-flight mass spectrometer systems affixed with reflectrons are valuable tools for investigating cluster dynamics and reactions, spectroscopy and structures. Utilizing the reflectron time-of-flight mass spectrometer techniques, both decay fractions and kinetic energy releases of metastable cluster ions can be measured with high precision. By applying related theoretical models, the desired thermochemical values of metastable species can be deduced, which are otherwise very difficult to obtain. Several examples are discussed with attention focused on ammonia as a test case for hydrogen bond systems, and xenon for weaker van der Waals clusters. A brief overview of applications to investigating solvation effects on reactions and structures, delayed electron transfer and ionization through intracluster Penning ionization is also given.

  4. Numerical Study of Tip Vortex Flows

    NASA Technical Reports Server (NTRS)

    Dacles-Mariani, Jennifer; Hafez, Mohamed

    1998-01-01

    This paper presents an overview and summary of the many different research work related to tip vortex flows and wake/trailing vortices as applied to practical engineering problems. As a literature survey paper, it outlines relevant analytical, theoretical, experimental and computational study found in literature. It also discusses in brief some of the fundamental aspects of the physics and its complexities. An appendix is also included. The topics included in this paper are: 1) Analytical Vortices; 2) Experimental Studies; 3) Computational Studies; 4) Wake Vortex Control and Management; 5) Wake Modeling; 6) High-Lift Systems; 7) Issues in Numerical Studies; 8) Instabilities; 9) Related Topics; 10) Visualization Tools for Vertical Flows; 11) Further Work Needed; 12) Acknowledgements; 13) References; and 14) Appendix.

  5. An Overview of NADE Accreditation

    ERIC Educational Resources Information Center

    Ferguson, Jennifer; Ludman, Naomi

    2018-01-01

    Accreditation is a process by which programs demonstrate their academic quality; that is, they demonstrate that they are making decisions for programmatic changes based on: (1) a sound theoretical foundation; (2) clearly stated mission, goals, and objectives; (3) a comprehensive self-study and thoughtful use of best practices; and (4) consistent,…

  6. Spanish Second Language Acquisition: State of the Science.

    ERIC Educational Resources Information Center

    Lafford, Barbara A., Ed.; Salaberry, Rafael, Ed.

    This collection of papers provides an overview of previous studies on the acquisition of Spanish as a second or foreign language, theoretical approaches used in these studies, and effects of various pedagogical approaches on the development of Spanish interlanguage systems. The 10 chapters include the following: (1) "Phonology: Staking Out…

  7. Emerging Approaches to Counseling Intervention: Theory, Research, Practice, and Training

    ERIC Educational Resources Information Center

    Murdock, Nancy L.; Duan, Changming; Nilsson, Johanna E.

    2012-01-01

    This article provides an overview of the major contribution that presents three emerging approaches to counseling: narrative therapy, dialectical behavior therapy, and acceptance and commitment therapy. The three theoretical systems were chosen because they are current, for the most part not addressed in the mainstream counseling psychology…

  8. Network Analysis in Comparative Social Sciences

    ERIC Educational Resources Information Center

    Vera, Eugenia Roldan; Schupp, Thomas

    2006-01-01

    This essay describes the pertinence of Social Network Analysis (SNA) for the social sciences in general, and discusses its methodological and conceptual implications for comparative research in particular. The authors first present a basic summary of the theoretical and methodological assumptions of SNA, followed by a succinct overview of its…

  9. Research in Self-Disclosure: An Annotated Bibliography.

    ERIC Educational Resources Information Center

    Breed, George; Jourard, Sidney M.

    This is an extensive compilation of abstracts of research in numerous areas as they relate to self-disclosure. No theoretical overview or introductory comments are included. Specific content areas, as listed in the index, include: (1) cross-cultural studies; (2) dyadic effect; (3) selective disclosure; (4) achievement; (5) adolescence; (6) age;…

  10. Semantic and Thematic List Learning of Second Language Vocabulary

    ERIC Educational Resources Information Center

    Gholami, Javad; Khezrlou, Sima

    2014-01-01

    This article overviews research on second language vocabulary instruction with a specific focus on semantic and thematic vocabulary-clustering types. The theoretical benefits associated with both the semantic and thematic approaches, as well as the potential problems associated with them, are discussed. The conclusion drawn is that reinforcing the…

  11. Civic Education and Citizenship in Malaysian Education.

    ERIC Educational Resources Information Center

    Barone, Thomas N.

    This paper seeks to provide an overview of theoretical concepts of civic education and citizenship. The paper discusses recent comparative education research on political socialization and its implications for future research, such as in not fully democratic countries like Malaysia. Based on a literature review and prior research in the region,…

  12. Empowerment through Experiential Learning: Explorations of Good Practice.

    ERIC Educational Resources Information Center

    Mulligan, John, Ed.; Griffin, Colin, Ed.

    This volume brings together papers from the 1991 Conference on Experiential Learning held at Surrey University (England); its 25 chapters are divided into 5 sections. An introduction provides a brief overview of each chapter. Section 1 is concerned with theoretical frameworks and philosophical and critical reflection: "Absorbing Experiential…

  13. Identity Development Process and Content: Toward an Integrated and Contextualized Science of Identity

    ERIC Educational Resources Information Center

    Galliher, Renee V.; Rivas-Drake, Deborah; Dubow, Eric F.

    2017-01-01

    This introductory summary provides an overview of the content of the special issue entitled "Identity Development Process and Content: Toward an Integrated and Contextualized Science of Identity." The 16 theoretical and empirical articles that comprise this special issue were selected to highlight innovative methodologies, theoretical…

  14. A Hindu Perspective to Organizational Learning

    ERIC Educational Resources Information Center

    Shama Rao, Ashok; Kamath Burde, Jyothsna

    2017-01-01

    Purpose: This paper aims to provide an overview of the relevance and applicability of the Hindu tradition to organizational learning. Design/methodology/approach: Attempting to separate the spiritual from the religious aspects, a primarily theoretical approach is used to delineate the basic concepts in Hinduism and their applicability to various…

  15. Asian American Acculturation and Enculturation: Construct Clarification and Measurement Consolidation

    ERIC Educational Resources Information Center

    Zhang, Shengying; Moradi, Bonnie

    2013-01-01

    An overview of the evolution of Asian American acculturation and enculturation theory and measurement is offered, focusing on major theoretical advancements and methodological issues that are salient for measuring these constructs. Informed by these considerations, an empirical approach is taken to clarifying the dimensions of Asian American…

  16. Selfhood and Context: Some Indian Solutions.

    ERIC Educational Resources Information Center

    Collins, Alfred; Prakash, Desai

    In this examination of East Indian theories about the self, an overview of two Indian concepts of self, "atman" and "ahamkara," is presented. Then, in an effort to uncover common theoretical grounds for understanding India's diverse views of the self, comparisons are made between Western psychoanalytic theories (e.g., the…

  17. Actionable Postcolonial Theory in Education. Postcolonial Studies in Education

    ERIC Educational Resources Information Center

    Andreotti, Vanessa

    2011-01-01

    "Actionable Postcolonial Theory in Education" illustrates how postcolonial theory can be put to work in education. It offers an accessible and handy overview and comparison of postcolonial theory and other theoretical debates related to critiques of Western ethnocentrism and hegemony. It also offers examples that illustrate how a discursive strand…

  18. Information Theory for Information Science: Antecedents, Philosophy, and Applications

    ERIC Educational Resources Information Center

    Losee, Robert M.

    2017-01-01

    This paper provides an historical overview of the theoretical antecedents leading to information theory, specifically those useful for understanding and teaching information science and systems. Information may be discussed in a philosophical manner and at the same time be measureable. This notion of information can thus be the subject of…

  19. Authentic Leadership Development in the Classroom: A Narrative Approach

    ERIC Educational Resources Information Center

    Albert, Joseph F.; Vadla, Kaitlin

    2009-01-01

    This paper examines how a classroom designed process of constructing narratives about oneself, a group, and others helps students develop an authentic leadership voice. We begin by describing the theoretical framework behind our paper, which includes an overview of the notion of authenticity and the linkage between narrative and authentic…

  20. The Promise for Geomorphic Discovery in the South.

    ERIC Educational Resources Information Center

    Mossa, Joann

    1998-01-01

    Presents an overview of current geomorphic research in the southern United States. Conveys that the limited historical effort offers both challenges and opportunities for conducting geomorphic work in the region; much is unknown about these unique landscapes. States applied and theoretical geomorphology will benefit the society and future of the…

  1. Simulation in JFL: Business Writing

    ERIC Educational Resources Information Center

    Fukushima, Tatsuya

    2007-01-01

    This article discusses a simulation wherein learners of Japanese as a Foreign Language (JFL) in a business writing course at an American university are assigned tasks to write a series of business letters based on situations that are likely to occur in actual business settings. After an overview of the theoretical background, this article…

  2. Physics Division annual review, 1 April 1975--31 March 1976. [ANL

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

    Garvey, G. T.

    1976-01-01

    An overview is given of Physics Division activities in the following areas: the heavy-ion booster; medium-energy physics; heavy-ion physics; low-energy charged-particle physics; accelerator operations; neutron physics; theoretical nuclear physics, and atomic and molecular physics. A bibliography of publications amounts to 27 pages. (RWR)

  3. Working with Bilingual Learners: An Introduction

    ERIC Educational Resources Information Center

    Willenberg, Ingrid

    2015-01-01

    This article seeks to provide a theoretical overview of bilingualism and discuss the key concepts and theories that inform classroom pedagogy with bilingual learners. Although some specific classroom strategies are introduced, the primary purpose is not to offer strategies, but rather to offer guiding principles based on theory and research to…

  4. Phonology, Reading Development, and Dyslexia: A Cross-Linguistic Perspective.

    ERIC Educational Resources Information Center

    Goswami, Usha

    2002-01-01

    This article presents a theoretical overview at the cognitive level of the role of phonological awareness in reading development and developmental dyslexia across languages. It is argued that the primary deficit in developmental dyslexia in all languages lies in representing speech sounds: a deficit in phonological representation. (Contains…

  5. The Use of Genograms in Educational Psychology Practice

    ERIC Educational Resources Information Center

    Tobias, Adele

    2018-01-01

    This article explores the application of the genogram in educational psychology (EP) practice. It provides a brief overview of the historical and theoretical development of the genogram. It then reviews and critiques some of the current literature regarding clinical application of the genogram in casework with children and adolescents and their…

  6. Feminist Literary Criticism; Explorations in Theory.

    ERIC Educational Resources Information Center

    Donovan, Josephine, Ed.

    A collection of five essays (plus preface and afterword) by noted feminist critics, this book provides an overview of the existing body of feminist literary criticism in order to promote an understanding of the issues feminist critics are currently discussing among themselves and with other critics. A theoretical framework for understanding this…

  7. Corporal Punishment and Alternatives in the Schools: An Overview of Theoretical and Practical Issues.

    ERIC Educational Resources Information Center

    Hyman, Irwin A.; And Others

    1978-01-01

    Many alternatives to the use of corporal punishment in the schools exist. Because the mass of survey data collected contraindicates the use of corporal punishment, the burden of proof of its effectiveness should be assumed by those who favor its use. (Author/WI)

  8. Universities and Globalization: Critical Perspectives.

    ERIC Educational Resources Information Center

    Currie, Jan, Ed.; Newson, Janice, Ed.

    The 14 papers in this collection examine how a globalizing political economy affects the way universities are governed, discussing practices such as managerialism, accountability, and privatization which represent a shift toward business values and a market agenda. Part 1 gives a theoretical overview of the globalization agenda. Part 2 gives three…

  9. Introduction to the Special Issue: New and Interdisciplinary Approaches to Linguistic Relativity

    ERIC Educational Resources Information Center

    Athanasopoulos, Panos; Bylund, Emanuel; Casasanto, Daniel

    2016-01-01

    This Special Issue of "Language Learning" presents an interdisciplinary state-of-the-art overview of current approaches to linguistic relativity. It contains empirical and theoretical studies and reflections on linguistic relativity from a variety of perspectives, such as associative learning, conceptual transfer, multilingual awareness,…

  10. Teaching Multicultural Leadership Using a Social Constructionist Approach

    ERIC Educational Resources Information Center

    Fine, Leigh E.

    2015-01-01

    Multicultural leadership education may be enhanced through the use of social construction literature as a theoretical frame. Here, I present a brief overview of social construction theory and demonstrate how its tenets overlap with the goal of encouraging students' intercultural competence. I then provide two classroom activities that illustrate…

  11. The Minnesota Articulation Project and Its Proficiency-Based Assessments.

    ERIC Educational Resources Information Center

    Chalhoub-Deville, Micheline

    1997-01-01

    Reports on the Minnesota Articulation Project, providing an overview of the projects' three principal working groups: political action, curriculum, and assessment. The article then outlines the theoretical underpinnings of the proficiency-based assessment instruments developed in French, German, and Spanish and describes in detail the content and…

  12. Infant Embodiment and Interembodiment: A Review of Sociocultural Perspectives

    ERIC Educational Resources Information Center

    Lupton, Deborah

    2013-01-01

    This article brings together a range of research and scholarship from various disciplines which have investigated and theorized social and cultural aspects of infants' bodies within the context of contemporary western societies. It begins with a theoretical overview of dominant concepts of infants' bodies, including discussion of the concepts of…

  13. Special issue on asteroids - Introduction

    NASA Astrophysics Data System (ADS)

    Novaković, Bojan; Hsieh, Henry H.; Gronchi, Giovanni F.

    2018-04-01

    The articles in this special issue are devoted to asteroids, small solar system bodies that primarily populate a region between the orbits of Mars and Jupiter, known as the asteroid belt, but can also be found throughout the Solar System. Asteroids are considered to be a key to understanding the formation and evolution of our planetary system. Their properties allow us to test current theoretical models and develop new theoretical concepts pertaining to evolutionary processes in the Solar System. There have been major advances in asteroid science in the last decade, and that trend continues. Eighteen papers accepted for this special issue cover a wide range of asteroid-related subjects, pushing the boundaries of our understanding of these intriguing objects even further. Here we provide the reader with a brief overview of these thrilling papers, with an invitation for interested scientists to read each work in detail for a better understanding of these recent cutting edge results. As many topics in asteroid science remain open challenges, we hope that this special issue will be an important reference point for future research on this compelling topic.

  14. Medical Exercise Therapy for Treating Musculoskeletal Pain: A Narrative Review of Results from Randomized Controlled Trials with a Theoretical Perspective.

    PubMed

    Lorås, H; Østerås, B; Torstensen, T A; Østerås, H

    2015-09-01

    The purpose of this narrative review is to present an overview and theoretical rationale of medical exercise therapy (MET) as a physiotherapeutic rehabilitation treatment for musculoskeletal pain conditions. Results from randomized controlled trials (RCTs) conducted on MET are also presented. Computerized searches for any RCTs were conducted on the MET concept in the databases PubMed, Medline, Embase and ISI Web of science up to 2013. Overall findings from five included MET RCTs are long-term (≥1 year) reductions in pain and improved physical and functional capabilities. These results are interpreted in the context of the biopsychosocial model, advancing the view of a dynamic interaction among physiologic, psychological and social factors that influence pain modulation. MET is a biopsychosocial treatment that reduces pain and improves activities of daily living in patients with a musculoskeletal pain condition. Pain modulation is a key feature of MET, and an important area for further research is to elucidate the specific mechanisms behind the treatment effects. Copyright © 2015 John Wiley & Sons, Ltd.

  15. Relapse prevention for addictive behaviors

    PubMed Central

    2011-01-01

    The Relapse Prevention (RP) model has been a mainstay of addictions theory and treatment since its introduction three decades ago. This paper provides an overview and update of RP for addictive behaviors with a focus on developments over the last decade (2000-2010). Major treatment outcome studies and meta-analyses are summarized, as are selected empirical findings relevant to the tenets of the RP model. Notable advances in RP in the last decade include the introduction of a reformulated cognitive-behavioral model of relapse, the application of advanced statistical methods to model relapse in large randomized trials, and the development of mindfulness-based relapse prevention. We also review the emergent literature on genetic correlates of relapse following pharmacological and behavioral treatments. The continued influence of RP is evidenced by its integration in most cognitive-behavioral substance use interventions. However, the tendency to subsume RP within other treatment modalities has posed a barrier to systematic evaluation of the RP model. Overall, RP remains an influential cognitive-behavioral framework that can inform both theoretical and clinical approaches to understanding and facilitating behavior change. PMID:21771314

  16. Calculation of protein-ligand binding affinities.

    PubMed

    Gilson, Michael K; Zhou, Huan-Xiang

    2007-01-01

    Accurate methods of computing the affinity of a small molecule with a protein are needed to speed the discovery of new medications and biological probes. This paper reviews physics-based models of binding, beginning with a summary of the changes in potential energy, solvation energy, and configurational entropy that influence affinity, and a theoretical overview to frame the discussion of specific computational approaches. Important advances are reported in modeling protein-ligand energetics, such as the incorporation of electronic polarization and the use of quantum mechanical methods. Recent calculations suggest that changes in configurational entropy strongly oppose binding and must be included if accurate affinities are to be obtained. The linear interaction energy (LIE) and molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) methods are analyzed, as are free energy pathway methods, which show promise and may be ready for more extensive testing. Ultimately, major improvements in modeling accuracy will likely require advances on multiple fronts, as well as continued validation against experiment.

  17. Control-Structure-Interaction (CSI) technologies and trends to future NASA missions

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Control-structure-interaction (CSI) issues which are relevant for future NASA missions are reviewed. This goal was achieved by: (1) reviewing large space structures (LSS) technologies to provide a background and survey of the current state of the art (SOA); (2) analytically studying a focus mission to identify opportunities where CSI technology may be applied to enhance or enable future NASA spacecraft; and (3) expanding a portion of the focus mission, the large antenna, to provide in-depth trade studies, scaling laws, and methodologies which may be applied to other NASA missions. Several sections are presented. Section 1 defines CSI issues and presents an overview of the relevant modeling and control issues for LLS. Section 2 presents the results of the three phases of the CSI study. Section 2.1 gives the results of a CSI study conducted with the Geostationary Platform (Geoplat) as the focus mission. Section 2.2 contains an overview of the CSI control design methodology available in the technical community. Included is a survey of the CSI ground-based experiments which were conducted to verify theoretical performance predictions. Section 2.3 presents and demonstrates a new CSI scaling law methodology for assessing potential CSI with large antenna systems.

  18. The Matter-Antimatter Asymmetry of the Universe

    NASA Technical Reports Server (NTRS)

    Stecker, F. W.; White, Nicholas E. (Technical Monitor)

    2002-01-01

    I will give here an overview of the present observational and theoretical situation regarding the question of the matter-antimatter asymmetry of the universe and the related question of the existence of antimatter on a cosmological scale. I will also give a simple discussion of the role of CP (charge conjugation parity) violation in this subject.

  19. The Income Generation Handbook: A Practical Guide for Educational Institutions.

    ERIC Educational Resources Information Center

    Warner, David; Leonard, Charles

    This book sets out the British policy context and theoretical framework for income generation by institutions of higher education and provides practical guidance in this area. Income generation is defined as all income generated over and above the core funding provided by an institution's primary funding body. Chapter 1 offers an overview of…

  20. Guiding the Family: Practical Counseling Techniques. Second Edition.

    ERIC Educational Resources Information Center

    Grunwald, Bernice Bronia; McAbee, Harold V.

    This text on principles of Adlerian Psychology is designed for use in family counseling. It begins with an overview of Alfred Adler and his basic philosophy on human relationships. Throughout the book, as the Adlerian theory is discussed, practical application of theory is explained for counselors. Counselors must have a firm theoretical basis for…

  1. Emotional Intelligence in Gifted Students

    ERIC Educational Resources Information Center

    Zeidner, Moshe; Matthews, Gerald

    2017-01-01

    This article aims at shedding light on the emotional intelligence (EI) of gifted and high ability students. We begin by presenting a brief overview of EI theory and research and its relevance to gifted education. We then present theoretical considerations bearing on the nature of the relationship between cognitive and EI. This is followed by a…

  2. Acceptance and Commitment Therapy (ACT) as a Career Counselling Strategy

    ERIC Educational Resources Information Center

    Hoare, P. Nancey; McIlveen, Peter; Hamilton, Nadine

    2012-01-01

    Acceptance and commitment therapy (ACT) has potential to contribute to career counselling. In this paper, the theoretical tenets of ACT and a selection of its counselling techniques are overviewed along with a descriptive case vignette. There is limited empirical research into ACT's application in career counselling. Accordingly, a research agenda…

  3. Complexity, Methodology and Method: Crafting a Critical Process of Research

    ERIC Educational Resources Information Center

    Alhadeff-Jones, Michel

    2013-01-01

    This paper defines a theoretical framework aiming to support the actions and reflections of researchers looking for a "method" in order to critically conceive the complexity of a scientific process of research. First, it starts with a brief overview of the core assumptions framing Morin's "paradigm of complexity" and Le…

  4. Issues and Theoretical Constructs regarding Parent Education for Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Steiner, Amanda M.; Koegel, Lynn K.; Koegel, Robert L.; Ence, Whitney A.

    2012-01-01

    Participation of parents of children with autism is commonplace in most comprehensive intervention programs, yet, there is limited research relating to the best practices in this area. This article provides an overview of parent education programs for young children with autism and details data-driven procedures which are associated with improved…

  5. The Internalization Theory of Emotions: A Cultural Historical Approach to the Development of Emotions

    ERIC Educational Resources Information Center

    Holodynski, Manfred

    2013-01-01

    Starting with an overview of theoretical approaches to emotion from an activity-oriented stance, this article applies Vygotsky's three general principles of development, sign mediation, and internalization to the development of emotional expressions as a culturally evolved sign system. The possible twofold function of expression signs as a means…

  6. Constructivist Viewpoints for School Teaching and Learning in Mathematics and Science. Research Report 131.

    ERIC Educational Resources Information Center

    Ahtee, Maija, Ed.; Pehkonen, Erkki, Ed.

    This research report contains a fairly concise overview of the role of constructivism in the teaching of mathematics and science in Finland. Included papers have been grouped into three parts. The first part, "General Considerations," consists of the seven articles on theoretical considerations, social constructivism, teachers' and pupils'…

  7. Food Reinforcement and Eating: A Multilevel Analysis

    ERIC Educational Resources Information Center

    Epstein, Leonard H.; Leddy, John J.; Temple, Jennifer L.; Faith, Myles S.

    2007-01-01

    Eating represents a choice among many alternative behaviors. The purpose of this review is to provide an overview of how food reinforcement and behavioral choice theory are related to eating and to show how this theoretical approach may help organize research on eating from molecular genetics through treatment and prevention of obesity. Special…

  8. U.S. Comparative and International Graduate Programs: An Overview of Programmatic Size, Relevance, Philosophy, and Methodology

    ERIC Educational Resources Information Center

    Drake, Timothy A.

    2011-01-01

    Previous work has concentrated on the epistemological foundation of comparative and international education (CIE) graduate programs. This study focuses on programmatic size, philosophy, methodology, and pedagogy. It begins by reviewing previous studies. It then provides a theoretical framework and describes the size, relevance, content, and…

  9. A Study of Child Variance, Volume 2: Interventions; Conceptual Project in Emotional Disturbance.

    ERIC Educational Resources Information Center

    Rhodes, William C.; Tracy, Michael L.

    Presented in the second volume of a series emanating from a conceptual project on emotional disturbance are six papers on general aspects of interventions as well as biophysical, behavioral, psychodynamic, environmental, and counter theoretical interventions. In an "Overview of Interventions", W. Rhodes discusses a framework for viewing…

  10. Applying Developmental Theory and Research to the Creation of Educational Games

    ERIC Educational Resources Information Center

    Revelle, Glenda

    2013-01-01

    The field of developmental psychology has produced abundant theory and research about the physical, cognitive, social, and emotional development of children; however, to date there has been limited use of this wealth of knowledge by developers creating games for children. This chapter provides an overview of key theoretical observations and…

  11. Solid Inflammability Boundary At Low-Speed (SIBAL)

    NASA Technical Reports Server (NTRS)

    T'ien, J.; Sacksteder, K.; Ferkul, P.; Pettegrew, R.; Street, K.; Kumar, A.; Tolejko, K.; Kleinhenz, J.; Piltch, N.

    2003-01-01

    This research program is concerned with the effect of low-speed flow on the spreading and extinction processes over solid fuels. The project has passed the Science Concept Review and the experiment is currently scheduled to be performed in the ISS Combustion Integrated Rack. We present an overview of recent and ongoing experimental and theoretical efforts.

  12. Exploring and Implementing Participatory Action Research

    ERIC Educational Resources Information Center

    Savin-Baden, Maggi; Wimpenny, Katherine

    2007-01-01

    This paper explores the research method of participatory action research, first by examining the roots of this approach and then analysing the shift to using more participatory approaches than in former years. It begins by considering the reasoning and theoretical underpinning for adopting this approach and provides an overview of the steps to be…

  13. Developing Student Interest: An Overview of the Research and Implications for Geoscience Education Research and Teaching Practice

    ERIC Educational Resources Information Center

    van der Hoeven Kraft, Katrien J.

    2017-01-01

    Interest is a complex interplay between affective and cognitive components that drive motivation. Over decades of work in the educational psychology community, a theoretical framework has emerged that explains this complex interplay. Interest is initially externally triggered (triggered situational interest), which, through support, can become…

  14. From Design to Implementation to Practice a Learning by Teaching System: Betty's Brain

    ERIC Educational Resources Information Center

    Biswas, Gautam; Segedy, James R.; Bunchongchit, Kritya

    2016-01-01

    This paper presents an overview of 10 years of research with the "Betty's Brain" computer-based learning environment. We discuss the theoretical basis for "Betty's Brain" and the learning-by-teaching paradigm. We also highlight our key research findings, and discuss how these findings have shaped subsequent research. Throughout…

  15. Empirical Scientific Research and Legal Studies Research--A Missing Link

    ERIC Educational Resources Information Center

    Landry, Robert J., III

    2016-01-01

    This article begins with an overview of what is meant by empirical scientific research in the context of legal studies. With that backdrop, the argument is presented that without engaging in normative, theoretical, and doctrinal research in tandem with empirical scientific research, the role of legal studies scholarship in making meaningful…

  16. Stress and Children: A Theoretical Overview.

    ERIC Educational Resources Information Center

    Duncan, David F.

    Children experience stress just as adults do. Various responses to stress can damage the body's health in at least two different ways. First, they may do direct damage to the tissues--especially those of the circulatory system. Second, and more often important to the health of children, they may suppress the body's natural defenses against…

  17. Towards a Postmodern Theory of Moral Education. Part I: Clearing the Terrain.

    ERIC Educational Resources Information Center

    Stams, Geert-Jan J. M.; Biesta, Gert J. J.

    This paper offers an overview of current debates on moral development and education, focusing on the relationship between empirical and theoretical research and raising four issues that are central to current research: (1) demarcation of the moral domain; (2) the gap between "is" and "ought," between facts and values; (3) moral…

  18. Critical Pedagogy(ies) for ELT in Indonesia

    ERIC Educational Resources Information Center

    Larson, Kasey R.

    2014-01-01

    This paper will explore the theoretical underpinnings that present a rationale for the use of critical pedagogy as an English Language Teaching (ELT) approach in Indonesia. A brief description of critical pedagogy is given, followed by a detailed rationale for its use including an overview of critical pedagogy studies done in Asia, an exploration…

  19. Guidelines for Online Assessment for Educators

    ERIC Educational Resources Information Center

    Westhuizen, Duan vd

    2016-01-01

    This work starts with a brief overview of education in developing countries, to contextualise the use of the guidelines. Although this document is intended to be a practical tool, it is necessary to include some theoretical analysis of the concept of online assessment. This is given in Sections 3 and 4, together with the identification and…

  20. 101 Ways To Build Enrollment in Your Early Childhood Program.

    ERIC Educational Resources Information Center

    Montanari, Ellen Orton

    Written for administrators of early childhood program centers, this book offers tips on how to increase enrollment. The book offers suggestions rather than a theoretical overview or a comprehensive marketing strategy. Suggestions offered include: (1) Offer a quality program; (2) be aware of your target market; (3) make your program unique; (4)…

  1. Blessed Oblivion? Knowledge and Metacognitive Accuracy in Online Social Networks

    ERIC Educational Resources Information Center

    Moll, Ricarda; Pieschl, Stephanie; Bromme, Rainer

    2015-01-01

    In order to reap the social gratifications of Online Social Networks (OSNs), users often disclose self-related information, making them potentially vulnerable to their online audiences. We give a brief overview of our theoretical ideas and empirical research about additional cognitive and metacognitive factors relevant for the perception of risk…

  2. A socio-technical model to explore urban water systems scenarios.

    PubMed

    de Haan, Fjalar J; Ferguson, Briony C; Deletic, Ana; Brown, Rebekah R

    2013-01-01

    This article reports on the ongoing work and research involved in the development of a socio-technical model of urban water systems. Socio-technical means the model is not so much concerned with the technical or biophysical aspects of urban water systems, but rather with the social and institutional implications of the urban water infrastructure and vice versa. A socio-technical model, in the view purported in this article, produces scenarios of different urban water servicing solutions gaining or losing influence in meeting water-related societal needs, like potable water, drainage, environmental health and amenity. The urban water system is parameterised with vectors of the relative influence of each servicing solution. The model is a software implementation of the Multi-Pattern Approach, a theory on societal systems, like urban water systems, and how these develop and go through transitions under various internal and external conditions. Acknowledging that social dynamics comes with severe and non-reducible uncertainties, the model is set up to be exploratory, meaning that for any initial condition several possible future scenarios are produced. This article gives a concise overview of the necessary theoretical background, the model architecture and some initial test results using a drainage example.

  3. Overview and evaluation of different nuclear level density models for the 123I radionuclide production.

    PubMed

    Nikjou, A; Sadeghi, M

    2018-06-01

    The 123 I radionuclide (T 1/2 = 13.22 h, β+ = 100%) is one of the most potent gamma emitters for nuclear medicine. In this study, the cyclotron production of this radionuclide via different nuclear reactions namely, the 121 Sb(α,2n), 122 Te(d,n), 123 Te(p,n), 124 Te(p,2n), 124 Xe(p,2n), 127 I(p,5n) and 127 I(d,6n) were investigated. The effect of the various phenomenological nuclear level density models such as Fermi gas model (FGM), Back-shifted Fermi gas model (BSFGM), Generalized superfluid model (GSM) and Enhanced generalized superfluid model (EGSM) moreover, the three microscopic level density models were evaluated for predicting of cross sections and production yield predictions. The SRIM code was used to obtain the target thickness. The 123 I excitation function of reactions were calculated by using of the TALYS-1.8, EMPIRE-3.2 nuclear codes and with data which taken from TENDL-2015 database, and finally the theoretical calculations were compared with reported experimental measurements in which taken from EXFOR database. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Functional connectivity dynamically evolves on multiple time-scales over a static structural connectome: Models and mechanisms.

    PubMed

    Cabral, Joana; Kringelbach, Morten L; Deco, Gustavo

    2017-10-15

    Over the last decade, we have observed a revolution in brain structural and functional Connectomics. On one hand, we have an ever-more detailed characterization of the brain's white matter structural connectome. On the other, we have a repertoire of consistent functional networks that form and dissipate over time during rest. Despite the evident spatial similarities between structural and functional connectivity, understanding how different time-evolving functional networks spontaneously emerge from a single structural network requires analyzing the problem from the perspective of complex network dynamics and dynamical system's theory. In that direction, bottom-up computational models are useful tools to test theoretical scenarios and depict the mechanisms at the genesis of resting-state activity. Here, we provide an overview of the different mechanistic scenarios proposed over the last decade via computational models. Importantly, we highlight the need of incorporating additional model constraints considering the properties observed at finer temporal scales with MEG and the dynamical properties of FC in order to refresh the list of candidate scenarios. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Pathways to recovery: promoting change within a developmental-systemic framework.

    PubMed

    Bryant-Waugh, Rachel

    2006-04-01

    This article describes a format for the process of achieving therapeutic change through structured individual sessions with adolescents or adults with eating disorders. It is a model for change based on three separate existing theoretical or conceptual strands: Developmental theory; the application of systems theory and cybernetics to clinical practice; and feminist ideology. It was developed as a pragmatic, clinician-friendly model that could be successfully used by therapists from different disciplines, and is referred to here as developmental-systemic-feminist therapy or individual developmental-systemic therapy. Change in this context is defined as the overt and measurable alteration in feelings, thoughts and behaviours of the participant(s) over the course of treatment. The article provides an overview of the treatment model and outlines the five steps used to achieve change (explore; understand; accept; challenge; change). Essential components of the therapist's stance, skills and knowledge are described, followed by a discussion of the structure and content of sessions in different stages of the therapy. Finally, clinical examples are given to illustrate the clinical use of this model in young patients with eating disorders.

  6. An overview of bioinformatics methods for modeling biological pathways in yeast

    PubMed Central

    Hou, Jie; Acharya, Lipi; Zhu, Dongxiao

    2016-01-01

    The advent of high-throughput genomics techniques, along with the completion of genome sequencing projects, identification of protein–protein interactions and reconstruction of genome-scale pathways, has accelerated the development of systems biology research in the yeast organism Saccharomyces cerevisiae. In particular, discovery of biological pathways in yeast has become an important forefront in systems biology, which aims to understand the interactions among molecules within a cell leading to certain cellular processes in response to a specific environment. While the existing theoretical and experimental approaches enable the investigation of well-known pathways involved in metabolism, gene regulation and signal transduction, bioinformatics methods offer new insights into computational modeling of biological pathways. A wide range of computational approaches has been proposed in the past for reconstructing biological pathways from high-throughput datasets. Here we review selected bioinformatics approaches for modeling biological pathways in S. cerevisiae, including metabolic pathways, gene-regulatory pathways and signaling pathways. We start with reviewing the research on biological pathways followed by discussing key biological databases. In addition, several representative computational approaches for modeling biological pathways in yeast are discussed. PMID:26476430

  7. Development of a high resolution interstellar dust engineering model - overview of the project

    NASA Astrophysics Data System (ADS)

    Sterken, V. J.; Strub, P.; Soja, R. H.; Srama, R.; Krüger, H.; Grün, E.

    2013-09-01

    Beyond 3 AU heliocentric distance, the flow of interstellar dust through the solar system is a dominant component of the total dust population. The modulation of this flux with the solar cycle and the position in the solar system has been predicted by theoretical studies since the seventies. The modulation was proven to exist by matching dust trajectory simulations with real spacecraft data from Ulysses in 1998. The modulations were further analyzed and studies in detail in 2012. The current ESA interplanetary meteoroid model IMEM includes an interstellar dust component, but this component was modelled only with straight line trajectories through the solar system. For the new ESA IMEX model, a high-resolution interstellar dust component is implemented separately from a dust streams module. The dust streams module focuses on dust in streams that was released from comets (cf. Abstract R. Soja). Parallel processing techniques are used to improve computation time (cf. Abstract P. Strub). The goal is to make predictions for the interstellar dust flux as close to the Sun as 1 AU or closer, for future space mission design.

  8. The Far Infrared Vibration-Rotation Spectrum of the Ammonia Dimer.

    NASA Astrophysics Data System (ADS)

    Loeser, Jennifer Gertrud

    1995-11-01

    The ammonia dimer has been shown to exhibit unusual weak bonding properties relative to those of the other prototypical second row systems, the hydrogen fluoride dimer and the water dimer. The ultimate goal of the work initiated in this dissertation is to determine a complete intermolecular potential energy surface for the ammonia dimer. It is first necessary to observe its far infrared vibration-rotation-tunneling (VRT) spectrum and to develop a group theoretical model that explains this spectrum in terms of the internal dynamics of the ammonia dimer. These first steps are the subject of this dissertation. First, the current understanding of the ammonia dimer system is reviewed. Group theoretical descriptions of the nature of the ammonia dimer VRT states are explained in detail. An overview of the experimental and theoretical studies of the ammonia dimer made during the last decade is presented. Second, progress on the analysis of the microwave and far infrared spectrum of (ND_3)_2 below 13 cm^{-1} is reported. These spectra directly measure the 'donor -acceptor' interchange splittings in (ND_3) _2, and determine some of the monomer umbrella inversion tunneling splittings. Third, new 80-90 cm^{-1} far infrared spectra of (NH_3)_2 are presented and a preliminary analysis is proposed. Most of the new excited VRT states have been assigned as tunneling sublevels of an out-of-plane intermolecular vibration.

  9. Combining Users’ Needs With Health Behavior Models in Designing an Internet- and Mobile-Based Intervention for Physical Activity in Cardiac Rehabilitation

    PubMed Central

    2014-01-01

    Background Internet-based physical activity interventions have great potential in supporting patients in cardiac rehabilitation. Health behavior change theories and user input are identified as important contributors in the effectiveness of the interventions, but they are rarely combined in a systematic way in the design of the interventions. Objective The aim of this study is to identify the appropriate theoretical framework, along with the needs of the users of a physical activity intervention for cardiac rehabilitation, and to combine them into an effective Internet- and mobile-based intervention. Methods We explain the theoretical framework of the intervention in a narrative overview of the existing health behavior change literature as it applies to physical activity. We also conducted a focus group with 11 participants of a cardiac rehabilitation program and used thematic analysis to identify and analyze patterns of meaning in the transcribed data. Results We chose stage-based approaches, specifically the transtheoretical model and the health action process approach as our main framework for tailoring, supplemented with other theoretical concepts such as regulatory focus within the appropriate stages. From the thematic analysis of the focus group data, we identified seven themes: (1) social, (2) motivation, (3) integration into everyday life, (4) information, (5) planning, (6) monitoring and feedback, and (7) concerns and potential problems. The final design of the intervention was based on both the theoretical review and the user input, and it is explained in detail. Conclusions We applied a combination of health behavioral theory and user input in designing our intervention. We think this is a promising design approach with the potential to combine the high efficacy of theory-based interventions with the higher perceived usefulness of interventions designed according to user input. Trial Registration Clinicaltrials.gov NCT01223170; http://clinicaltrials.gov/show/NCT01223170 (Archived by WebCite at http://www.webcitation.org/6M5FqT9Q2). PMID:24413185

  10. Evolutionary and ecological approaches to the study of personality

    PubMed Central

    Réale, Denis; Dingemanse, Niels J.; Kazem, Anahita J. N.; Wright, Jonathan

    2010-01-01

    This introduction to the themed issue on Evolutionary and ecological approaches to the study of personality provides an overview of conceptual, theoretical and methodological progress in research on animal personalities over the last decade, and places the contributions to this volume in context. The issue has three main goals. First, we aimed to bring together theoreticians to contribute to the development of models providing adaptive explanations for animal personality that could guide empiricists, and stimulate exchange of ideas between the two groups of researchers. Second, we aimed to stimulate cross-fertilization between different scientific fields that study personality, namely behavioural ecology, psychology, genomics, quantitative genetics, neuroendocrinology and developmental biology. Third, we aimed to foster the application of an evolutionary framework to the study of personality. PMID:21078646

  11. Stability of streamwise vortices

    NASA Technical Reports Server (NTRS)

    Khorrami, M. K.; Grosch, C. E.; Ash, R. L.

    1987-01-01

    A brief overview of some theoretical and computational studies of the stability of streamwise vortices is given. The local induction model and classical hydrodynamic vortex stability theories are discussed in some detail. The importance of the three-dimensionality of the mean velocity profile to the results of stability calculations is discussed briefly. The mean velocity profile is provided by employing the similarity solution of Donaldson and Sullivan. The global method of Bridges and Morris was chosen for the spatial stability calculations for the nonlinear eigenvalue problem. In order to test the numerical method, a second order accurate central difference scheme was used to obtain the coefficient matrices. It was shown that a second order finite difference method lacks the required accuracy for global eigenvalue calculations. Finally the problem was formulated using spectral methods and a truncated Chebyshev series.

  12. An Overview of Depression among Transgender Women

    PubMed Central

    2014-01-01

    Rates of depression are higher in transgender women than in the general population, warranting an understanding of the variables related to depression in this group. Results of the literature review of depression in transgender women reveal several variables influencing depression, including social support, violence, sex work, and gender identity. The theoretical constructs of minority stress, coping, and identity control theory are explored in terms of how they may predict depression in transgender women. Depression and depressive symptoms have been used to predict high-risk sexual behaviors with mixed results. The implications of the findings on treating depression in transgender women include taking into account the stress of transition and the importance of supportive peers and family. Future studies should explore a model of depression and high-risk behaviors in transgender women. PMID:24744918

  13. The Birth of Planetary Systems

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.; Young, Richard E. (Technical Monitor)

    1997-01-01

    An overview of current theories of star and planet formation is presented. These models are based upon observations of the Solar System and of young stars and their environments, and they predict that rocky planets should form around most single stars, although it is possible that in some cases such planets are lost to orbital decay within the protoplanetary disk. The frequency of formation of gas giant planets is more difficult to predict theoretically. Terrestrial planets are believed to grow via pairwise accretion until the spacing of planetary orbits becomes large enough that the configuration is stable for the age of the system. Giant planets begin their growth like terrestrial planets, but they become massive enough that they are able to accumulate substantial amounts of gas before the protoplanetary disk dissipates.

  14. Organizational readiness for knowledge translation in chronic care: a review of theoretical components

    PubMed Central

    2013-01-01

    Background With the persistent gaps between research and practice in healthcare systems, knowledge translation (KT) has gained significance and importance. Also, in most industrialized countries, there is an increasing emphasis on managing chronic health conditions with the best available evidence. Yet, organizations aiming to improve chronic care (CC) require an adequate level of organizational readiness (OR) for KT. Objectives: The purpose of this study is to review and synthesize the existing evidence on conceptual models/frameworks of Organizational Readiness for Change (ORC) in healthcare as the basis for the development of a comprehensive framework of OR for KT in the context of CC. Data sources We conducted a systematic review of the literature on OR for KT in CC using Pubmed, Embase, CINAHL, PsychINFO, Web of Sciences (SCI and SSCI), and others. Search terms included readiness; commitment and change; preparedness; willing to change; organization and administration; and health and social services. Study selection: The search was limited to studies that had been published between the starting date of each bibliographic database (e.g., 1964 for PubMed) and November 1, 2012. Only papers that refer to a theory, a theoretical component from any framework or model on OR that were applicable to the healthcare domain were considered. We analyzed data using conceptual mapping. Data extraction: Pairs of authors independently screened the published literature by reviewing their titles and abstracts. Then, the two same reviewers appraised the full text of each study independently. Results Overall, we found and synthesized 10 theories, theoretical models and conceptual frameworks relevant to ORC in healthcare described in 38 publications. We identified five core concepts, namely organizational dynamics, change process, innovation readiness, institutional readiness, and personal readiness. We extracted 17 dimensions and 59 sub-dimensions related to these 5 concepts. Conclusion Our findings provide a useful overview for researchers interested in ORC and aims to create a consensus on the core theoretical components of ORC in general and of OR for KT in CC in particular. However, more work is needed to define and validate the core elements of a framework that could help to assess OR for KT in CC. PMID:24283365

  15. Niche construction game cancer cells play

    NASA Astrophysics Data System (ADS)

    Bergman, Aviv; Gligorijevic, Bojana

    2015-10-01

    Niche construction concept was originally defined in evolutionary biology as the continuous interplay between natural selection via environmental conditions and the modification of these conditions by the organism itself. Processes unraveling during cancer metastasis include construction of niches, which cancer cells use towards more efficient survival, transport into new environments and preparation of the remote sites for their arrival. Many elegant experiments were done lately illustrating, for example, the premetastatic niche construction, but there is practically no mathematical modeling done which would apply the niche construction framework. To create models useful for understanding niche construction role in cancer progression, we argue that a) genetic, b) phenotypic and c) ecological levels are to be included. While the model proposed here is phenomenological in its current form, it can be converted into a predictive outcome model via experimental measurement of the model parameters. Here we give an overview of an experimentally formulated problem in cancer metastasis and propose how niche construction framework can be utilized and broadened to model it. Other life science disciplines, such as host-parasite coevolution, may also benefit from niche construction framework adaptation, to satisfy growing need for theoretical considerations of data collected by experimental biology.

  16. Niche construction game cancer cells play.

    PubMed

    Bergman, Aviv; Gligorijevic, Bojana

    2015-10-01

    Niche construction concept was originally defined in evolutionary biology as the continuous interplay between natural selection via environmental conditions and the modification of these conditions by the organism itself. Processes unraveling during cancer metastasis include construction of niches, which cancer cells use towards more efficient survival, transport into new environments and preparation of the remote sites for their arrival. Many elegant experiments were done lately illustrating, for example, the premetastatic niche construction, but there is practically no mathematical modeling done which would apply the niche construction framework. To create models useful for understanding niche construction role in cancer progression, we argue that a) genetic, b) phenotypic and c) ecological levels are to be included. While the model proposed here is phenomenological in its current form, it can be converted into a predictive outcome model via experimental measurement of the model parameters. Here we give an overview of an experimentally formulated problem in cancer metastasis and propose how niche construction framework can be utilized and broadened to model it. Other life science disciplines, such as host-parasite coevolution, may also benefit from niche construction framework adaptation, to satisfy growing need for theoretical considerations of data collected by experimental biology.

  17. An overview of the fundamental aerodynamics branch's research activities in wing leading-edge vortex flows at supersonic speeds

    NASA Technical Reports Server (NTRS)

    Miller, D. S.; Wood, R. M.; Covell, P. F.

    1986-01-01

    For the past 3 years, a research program pertaining to the study of wing leading edge vortices at supersonic speeds has been conducted in the Fundamental Aerodynamics Branch of the High-Speed Aerodynamics Division at the Langley Research Center. The purpose of the research is to provide an understanding of the factors governing the formation and the control of wing leading-edge vortices and to evaluate the use of these vortices for improving supersonic aerodynamic performance. The studies include both experimental and theoretical investigations and focus primarily on planform, thickness and camber effects for delta wings. An overview of this research activity is presented.

  18. Overview: Homogeneous nucleation from the vapor phase-The experimental science.

    PubMed

    Wyslouzil, Barbara E; Wölk, Judith

    2016-12-07

    Homogeneous nucleation from the vapor phase has been a well-defined area of research for ∼120 yr. In this paper, we present an overview of the key experimental and theoretical developments that have made it possible to address some of the fundamental questions first delineated and investigated in C. T. R. Wilson's pioneering paper of 1897 [C. T. R. Wilson, Philos. Trans. R. Soc., A 189, 265-307 (1897)]. We review the principles behind the standard experimental techniques currently used to measure isothermal nucleation rates, and discuss the molecular level information that can be extracted from these measurements. We then highlight recent approaches that interrogate the vapor and intermediate clusters leading to particle formation, more directly.

  19. The Educational Benefits Claimed for Physical Education and School Sport: An Academic Review

    ERIC Educational Resources Information Center

    Bailey, Richard; Armour, Kathleen; Kirk, David; Jess, Mike; Pickup, Ian; Sandford, Rachel

    2009-01-01

    This academic review critically examines the theoretical and empirical bases of claims made for the educational benefits of physical education and school sport (PESS). An historical overview of the development of PESS points to the origins of claims made in four broad domains: physical, social, affective and cognitive. Analysis of the evidence…

  20. Promoting Students' Ability to Think Conceptually in Calculus

    ERIC Educational Resources Information Center

    Zerr, Ryan J.

    2010-01-01

    An overview is given of three conceptual lessons that can be incorporated into any first-semester calculus class. These lessons were developed to help promote calculus students' ability to think conceptually, in particular with regard to the role that infinity plays in the subject. A theoretical basis for the value of these lessons is provided,…

  1. Teaching and Learning in Later Life: Theoretical Implications. Studies in Educational Gerontology 4.

    ERIC Educational Resources Information Center

    Glendenning, Frank

    This book contains nine papers on the development of education for older adults in the United Kingdom and Canada against the background of an aging population and the challenge of lengthening life expectancy. "Foreword" (David James) presents an overview of the book's contents and underscores the importance of motivation to learning in…

  2. Research on Language Teaching and Learning in Austria (2004-2009)

    ERIC Educational Resources Information Center

    Dalton-Puffer, Christiane; Faistauer, Renate; Vetter, Eva

    2011-01-01

    This overview of six years of research on language learning and teaching in Austria covers a period of dynamic development in the field. While all the studies reviewed here illustrate research driven by a combination of local and global concerns and theoretical frameworks, some specific clusters of research interest emerge. The first of these…

  3. The Political Vocabulary of Hong Kong English.

    ERIC Educational Resources Information Center

    Benson, Phil

    1994-01-01

    A study analyzed patterns of usage of political vocabulary in Hong Kong English as found in newspaper reports of a leading Hong Kong English-medium newspaper and two other English-medium newspapers. Data were drawn from a computerized corpus and a clippings file. The report begins with an overview of the theoretical basis of the study of ideology…

  4. Episodic Autobiographical Memories over the Course of Time: Cognitive, Neuropsychological and Neuroimaging Findings

    ERIC Educational Resources Information Center

    Piolino, Pascale; Desgranges, Beatrice; Eustache, Francis

    2009-01-01

    The critical attributes of episodic memory are self, autonoetic consciousness and subjectively sensed time. The aim of this paper is to present a theoretical overview of our already published researches into the nature of episodic memory over the course of time. We have developed a new method of assessing "autobiographical" memory (TEMPau task),…

  5. Integrating Computer-Based Career Development into Your Career Planning Program.

    ERIC Educational Resources Information Center

    Campbell, Robert B.; Mack, Sharon E.

    This paper focuses on the real and theoretical usefulness of a computer-based career development system in a career planning program, based on a 2-year pilot program evaluating the DISCOVER system. The system overview discusses components and contents of DISCOVER, and describes the 11 modules which assist users in learning about their values,…

  6. The Case of Educational Peacebuilding inside the United Nations Universities: A Review and Critique

    ERIC Educational Resources Information Center

    Kester, Kevin

    2017-01-01

    This article examines higher education for peace inside the United Nations (UN). It offers an overview and synthesis of core concepts, organizing frameworks and theoretical premises in the field of peace and conflict studies (PACS) higher education and in the UN universities in particular, as the field aspires toward transformative learning and…

  7. Integrating Behavioral Health Support into a Pediatric Setting: What Happens in the Exam Room?

    ERIC Educational Resources Information Center

    Cuno, Kate; Krug, Laura M.; Umylny, Polina

    2015-01-01

    This article presents an overview of the Healthy Steps for Young Children (Healthy Steps) program at Montefiore Medical Center, in the Bronx, NY. The authors review the theoretical underpinnings of this national program for the promotion of early childhood mental health. The Healthy Steps program at Montefiore is integrated into outpatient…

  8. Digital Literacy and Sustainability--A Field Study in EFL Teacher Development

    ERIC Educational Resources Information Center

    Allen, Christopher; Berggren, Jan

    2016-01-01

    This project introduces the concept of digital literacy at a practical level to a group of EFL teachers within the context of a single work place; a technologically well-resourced upper secondary school in Sweden. English teachers were provided with a theoretical and practical overview of the digital literacy concept as described by Dudeney,…

  9. Qualitative Research David Silverman Qualitative Research Sage Publications £26.99 464pp 9781849204170 1849204179 [Formula: see text].

    PubMed

    2012-01-26

    DAVID SILVERMAN'S latest book builds on previous editions to provide up-to-date development in qualitative research and offers an overview of theoretical and practical considerations. Unlike many other qualitative research methodology books there is an emphasis on the function of qualitative research to articulate meaning.

  10. A Synthesis of Language Learning Strategies: Current Issues, Problems and Claims Made in Learner Strategy Research

    ERIC Educational Resources Information Center

    Barjesteh, Hamed; Mukundan, Jayakaran; Vaseghi, Reza

    2014-01-01

    The current paper presented theoretical assumptions behind language learning strategies (LLS) and an overview of methods used to identify learners' strategies, first, and then summarized what have been reported from large number of descriptive studies of strategies by language learners. Moreover, the paper tried to present the variety of…

  11. Land use and land cover dynamics in the Brazilian Amazon: an overview

    Treesearch

    Robert Walker; Alfredo Kingo Oyama Homma

    1996-01-01

    This paper presents a theoretical discussion of processes linking land use decisions and land cover outcomes at household level, with an emphasis on small proceduers. Evidence from the literature substantiating the existence of domestic cycle phenomena is brought forward and interpreted for the Brazilian case. Also considered are the relative disposition of production...

  12. Solid State Cooling with Advanced Oxide Materials

    DTIC Science & Technology

    2014-06-03

    Department of Materials Science and Engineering , Department of Mechanical Science and Engineering , and Department of Electrical and Computer... Engineering University of Illinois, Urbana-Champaign Program Overview The focus of this program was to probe electro-(magneto-)caloric materials for... engineering systems by developing theoretical and experimental approaches to study thermodynamic properties and effects in thin film systems. Despite

  13. Cross Situational Consistency of Communication Behaviors: A Theoretical Overview, Apprehension, Androgyny, Organizational Relationships: Trust/Satisfaction.

    ERIC Educational Resources Information Center

    Phelps, Lynn; And Others

    Three studies tested the capability of three measurement instruments to predict a communication behavior across a variety of communication situations. The intent of these related studies was to demonstrate the utility of a self-presentation analysis of the concept of personality, an approach postulating that people strive to create the impression…

  14. Spin dynamics in storage rings and linear accelerators

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

    Irwin, J.

    1994-12-01

    The purpose of these lectures is to survey the subject of spin dynamics in accelerators: to give a sense of the underlying physics, the typical analytic and numeric methods used, and an overview of results achieved. Consideration will be limited to electrons and protons. Examples of experimental and theoretical results in both linear and circular machines are included.

  15. A Review on Studies of Phrasal Verb Constructions in ESL Context

    ERIC Educational Resources Information Center

    Jahedi, Maryam; Mukundan, Jayakaran

    2015-01-01

    This paper aims to give an overview of studies on phrasal verbs in three decades to present the theoretical and methodological issues, as well as the findings of research. Moreover, this review reveals the developments and paradigm shifts occurred in this area. Previous studies have shown that the research findings have not been incorporated into…

  16. Problems in Choosing a Theory of Basic Writing: Toward a Rhetoric of Scholarly Discourse.

    ERIC Educational Resources Information Center

    Bizzell, Patricia

    This paper discusses some of the problems faced in working with competing theories of basic writing and suggests its own kind of theoretical analysis of nonstandard writing. A brief overview of basic writing theories is presented, and the theories are categorized into two approaches: a traditional approach of teaching by prescription in an…

  17. Emotion and emotion regulation: from another perspective.

    PubMed

    Langlois, Judith H

    2004-01-01

    An overview of the content of the From Another Perspective collection on emotion and emotion regulation is provided. The lead article identifies fundamental issues of definition and the commentaries represent varying theoretical and methodological perspectives on emotion and emotion regulation. Together, the articles discuss the promises and pitfalls of emotion research and its potential for understanding child development.

  18. PUBLIC EDUCATION FOR DISTURBED CHILDREN IN NEW YORK CITY, APPLICATION AND THEORY.

    ERIC Educational Resources Information Center

    BERKOWITZ, PEARL H.; ROTHMAN, ESTHER P.

    CONCERNED WITH PUBLIC EDUCATION FOR DISTURBED CHILDREN, VARIOUS AUTHORS DISCUSS PROGRAMS OF THE NEW YORK CITY PUBLIC SCHOOL SYSTEM AND PRESENT SOME THEORETICAL FORMULATIONS. PROGRAMS CONSIDERED ARE (1) "EDUCATING DISTURBED CHILDREN IN NEW YORK CITY--AN HISTORICAL OVERVIEW" BY PEARL H. BERKOWITZ AND ESTHER P. ROTHMAN, (2) "THESE ARE OUR CHILDREN"…

  19. Who "owns" the network: a case study of new media artists' use of high-bandwidth networks

    NASA Astrophysics Data System (ADS)

    Lesage, F.

    The objective of this paper is to briefly give an overview of a research project dealing with the social construction of use of information communication technologies among new media artists interested in online collaboration. It will outline the theoretical and methodological tools applied to the case study of the MARCEL Network.

  20. Qualitative and Quantitative Approaches to the Study of Poverty: Taming the Tensions and Appreciating the Complementarities

    ERIC Educational Resources Information Center

    Balarabe Kura, Sulaiman Y.

    2012-01-01

    There is a germane relationship between qualitative and quantitative approaches to social science research. The relationship is empirically and theoretically demonstrated by poverty researchers. The study of poverty, as argued in this article, is a study of both numbers and contextualities. This article provides a general overview of qualitative…

  1. Errors and Intelligence in Computer-Assisted Language Learning: Parsers and Pedagogues. Routledge Studies in Computer Assisted Language Learning

    ERIC Educational Resources Information Center

    Heift, Trude; Schulze, Mathias

    2012-01-01

    This book provides the first comprehensive overview of theoretical issues, historical developments and current trends in ICALL (Intelligent Computer-Assisted Language Learning). It assumes a basic familiarity with Second Language Acquisition (SLA) theory and teaching, CALL and linguistics. It is of interest to upper undergraduate and/or graduate…

  2. Theoretical overview and modeling of the sodium and potassium atmospheres of mercury

    NASA Technical Reports Server (NTRS)

    Smyth, William H.; Marconi, M. L.

    1995-01-01

    A general theoretical overview for the sources, sinks, gas-surface interactions, and transport dynamics of sodium and potassium in the exospheric atmsophere of Mercury is given. Information for these four factors, which control the spatial distribution of these two alkali-group gases about the planet, is incorporated in numerical models. The spatial nature and relative importance of the initial source atom atmosphere and the ambient (ballistic hopping) atom atmosphere are then examined and are shown to be controlled and coupled to a great extent by the extremely large and variable solar radiation acceleration experienced by sodium and potassium as they resonantly scatter solar photons. The lateral (antisunward) transport rate of thermally accommodated sodium and potassium ambient atoms is shown to be driven by the solar radiation acceleration and, over a significant portion of Mercury's orbit about the Sun, is sufficiently rapid to be competitive with the short photoionization lifetimes for these atoms when they are located on the summit surface near or within about 30 deg of the terminator. The lateral transport rate is characterized by a migration time determined by model calculations for an ensemble of atoms initially starting at a point source on the surface (i.e., a numerical spacetime dependent Green's function). Four animations for the spacetime evolution of the sodium (or potassium) atmosphere produced by a point source on the surface are presented on a videotape format. For extended surface sources for sodium and potassium, the local column density is determined by competition between the photoionization lifetimes and the lateral transport times of atoms originating from different surface source locations. Sodium surface source fluxes (referenced to Mercury at perihelion) that are required on the sunlit hemisphere to reproduce the typically observed several megarayleighs of D2 emission-line brightness and the inferred column densities of 1-2 x 10(exp 11) atoms per sq cm range from approximately 2-5 x 10(exp 7) atoms/sq cm/sec. The sodium model is applied to study observational data that document an anticorrelation in the average sodium column density and solar radiation acceleration. Lateral transport driven by the solar radiation acceleration is shown to produce this behavior for combinations of different sources and surface accomodation coefficients. The best fit model fits to the observational data require a significant degree of thermal accommodation of the ambient sodium atoms to the surface and a source rate that decreases as an inverse power of 1.5 to 2 in heliocentric distance.

  3. An ecological framework of place: situating environmental gerontology within a life course perspective.

    PubMed

    Moore, Keith Diaz

    2014-01-01

    This article presents an emergent heuristic framework for the core environmental gerontology concept of "place." Place has been a central concern in the field since the 1970s (Gubrium, 1978) for its hypothesized direct relationship to identity, the self, and agency--suggestive of the appropriateness of lateral theoretical linkages with developmental science. The Ecological Framework of Place (EFP) defines place as a socio-physical milieu involving people, the physical setting, and the program of the place, all catalyzed by situated human activity and fully acknowledging that all four may change over time. The article begins with a concise overview of the EFP before moving on to consider it within three theoretical terrains: place theory, developmental science theory, and environmental gerontology theory. The EFP will be argued to be a place theory which subsumes themes of emergent environmental gerontology theories within a developmental science perspective. Implications for theory, method and practice are discussed. One of the strengths of the model is its ability to serve both research and practice, as is exhibited in its ability to incorporate applied design research and inform architectural decision-making so often lacking in other environmental gerontology models. Place should be viewed as an integrative concept providing opportunities for both environmental gerontology and developmental science to more critically concern the profound role places have in terms of agency, identity and sense of self over the life course.

  4. Surface-screening mechanisms in ferroelectric thin films and their effect on polarization dynamics and domain structures

    NASA Astrophysics Data System (ADS)

    Kalinin, Sergei V.; Kim, Yunseok; Fong, Dillon D.; Morozovska, Anna N.

    2018-03-01

    For over 70 years, ferroelectric materials have been one of the central research topics for condensed matter physics and material science, an interest driven both by fundamental science and applications. However, ferroelectric surfaces, the key component of ferroelectric films and nanostructures, still present a significant theoretical and even conceptual challenge. Indeed, stability of ferroelectric phase per se necessitates screening of polarization charge. At surfaces, this can lead to coupling between ferroelectric and semiconducting properties of material, or with surface (electro) chemistry, going well beyond classical models applicable for ferroelectric interfaces. In this review, we summarize recent studies of surface-screening phenomena in ferroelectrics. We provide a brief overview of the historical understanding of the physics of ferroelectric surfaces, and existing theoretical models that both introduce screening mechanisms and explore the relationship between screening and relevant aspects of ferroelectric functionalities starting from phase stability itself. Given that the majority of ferroelectrics exist in multiple-domain states, we focus on local studies of screening phenomena using scanning probe microscopy techniques. We discuss recent studies of static and dynamic phenomena on ferroelectric surfaces, as well as phenomena observed under lateral transport, light, chemical, and pressure stimuli. We also note that the need for ionic screening renders polarization switching a coupled physical–electrochemical process and discuss the non-trivial phenomena such as chaotic behavior during domain switching that stem from this. ).

  5. The SOFIA Massive (SOMA) Star Formation Survey. I. Overview and First Results

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

    De Buizer, James M.; Shuping, Ralph; Liu, Mengyao

    We present an overview and first results of the Stratospheric Observatory For Infrared Astronomy Massive (SOMA) Star Formation Survey, which is using the FORCAST instrument to image massive protostars from ∼10 to 40 μ m. These wavelengths trace thermal emission from warm dust, which in Core Accretion models mainly emerges from the inner regions of protostellar outflow cavities. Dust in dense core envelopes also imprints characteristic extinction patterns at these wavelengths, causing intensity peaks to shift along the outflow axis and profiles to become more symmetric at longer wavelengths. We present observational results for the first eight protostars in themore » survey, i.e., multiwavelength images, including some ancillary ground-based mid-infrared (MIR) observations and archival Spitzer and Herschel data. These images generally show extended MIR/FIR emission along directions consistent with those of known outflows and with shorter wavelength peak flux positions displaced from the protostar along the blueshifted, near-facing sides, thus confirming qualitative predictions of Core Accretion models. We then compile spectral energy distributions and use these to derive protostellar properties by fitting theoretical radiative transfer models. Zhang and Tan models, based on the Turbulent Core Model of McKee and Tan, imply the sources have protostellar masses m {sub *} ∼ 10–50 M {sub ⊙} accreting at ∼10{sup −4}–10{sup −3} M {sub ⊙} yr{sup −1} inside cores of initial masses M {sub c} ∼ 30–500 M {sub ⊙} embedded in clumps with mass surface densities Σ{sub cl} ∼ 0.1–3 g cm{sup −2}. Fitting the Robitaille et al. models typically leads to slightly higher protostellar masses, but with disk accretion rates ∼100× smaller. We discuss reasons for these differences and overall implications of these first survey results for massive star formation theories.« less

  6. Absorption of Solar Radiation by Clouds: A Second Look at Irradiance Measurements

    NASA Technical Reports Server (NTRS)

    Tsay, Si-Chee; King, Michael D.; Cahalan, Robert F.; Lau, William K.-M. (Technical Monitor)

    2001-01-01

    A decade ago, Stephens and Tsay provided an overview of the subject of absorption of solar radiation by clouds in the earth's atmosphere. They summarized the available evidence that pointed to disagreements between theoretical and observed values of cloud absorption (and reflection). At that time, a theoretician's approach (assuming perfect flux measurements) was adopted to test the model uncertainty under various hypotheses, such as the omitted large drops, excess absorbing aerosols, enhanced water vapor continuum absorption, and cloud inhomogeneity. Since then, several advances in theoretical work have been made, but a satisfactory answer for the discrepancy is still lacking. Now, we offer an experimentalist's approach (focusing on field, not laboratory) to examine the observational uncertainty under numerous field factors, such as the temperature dependence, attitude control, and sampling strategy in the spatial and spectral domain. Examples from recent field campaigns have pointed out that these sources of error may be responsible for the unacceptable level of uncertainty (e.g., as large as 20 W/square m). We give examples of each, discuss their contribution to overall uncertainty in shortwave absorption, and suggest a coordinated approach to their solution.

  7. Resource Letter GrW-1: Gravitational Waves

    NASA Technical Reports Server (NTRS)

    White, Nicholas E. (Technical Monitor); Centrella, Joan M.

    2003-01-01

    The phenomenon of gravitational radiation was one of the first predictions of Einstein's general theory of relativity. Progress in understanding this radiation theoretically was slow at first, owing to the difficulty of the nonlinear field equations and the subtleties of their physical effects. The experimental side of this subject also has taken a long time to develop, with efforts at detection severely challenged by the extreme weakness of the waves impinging on the Earth. However, as the 21st century begins, observations of the gravitational waves from astrophysical sources such as black holes, neutron stars, and stellar collapse are expected to open a new window on the universe. Vigorous experimental programs centered on ground-based detectors are being carried out worldwide, and a space-based detector is in the planning stages. On the theoretical side, much effort is being expended to produce robust models of the astrophysical sources and accurate calculations of the waveforms they produce. In this Resource Letter, a set of basic references will be presented first, to provide a general introduction to and overview of the literature in this field. The focus then will shift to highlighting key resources in more specialized areas at the forefront of current research.

  8. The 'whole-animal approach' as a heuristic principle in neuroscience research.

    PubMed

    Serani-Merlo, Alejandro; Paz, Rodrigo; Castillo, Andrés

    2005-01-01

    Neuroscience embraces a heterogeneous group of disciplines. A conceptual framework that allows a better articulation of these different theoretical and experimental perspectives is needed. A 'whole-animal approach is proposed as a theoretical and hermeneutic tool. To illustrate the potential of this point of view, an overview of the research that has been performed in the extinction of fear-conditioned responses from Pavlov to the present is discussed. This is an example of how a whole-animal-based approach may help to organize and integrate basic and clinical neuroscience research. Our proposal is in agreement with recent statements calling for more integrative approaches in biological and neuropsychiatric research.

  9. Theories of intimate partner violence: from blaming the victim to acting against injustice: intersectionality as an analytic framework.

    PubMed

    Kelly, Ursula A

    2011-01-01

    Intimate partner violence (IPV) has garnered increasing public and academic attention in the past several decades. Theories about the causes, prevention, and intervention for IPV have developed in complexity. This article provides an overview of the historical roots of IPV, as well as a description and critique of historical and contemporary theories of IPV causes and women's responses to IPV. This is followed by a discussion of the most current theoretical developments and application of critical theories to the problem of IPV. The article concludes with theoretically based implications for nursing practice and research with women who are experiencing IPV.

  10. Quantum spin liquids: a review.

    PubMed

    Savary, Lucile; Balents, Leon

    2017-01-01

    Quantum spin liquids may be considered 'quantum disordered' ground states of spin systems, in which zero-point fluctuations are so strong that they prevent conventional magnetic long-range order. More interestingly, quantum spin liquids are prototypical examples of ground states with massive many-body entanglement, which is of a degree sufficient to render these states distinct phases of matter. Their highly entangled nature imbues quantum spin liquids with unique physical aspects, such as non-local excitations, topological properties, and more. In this review, we discuss the nature of such phases and their properties based on paradigmatic models and general arguments, and introduce theoretical technology such as gauge theory and partons, which are conveniently used in the study of quantum spin liquids. An overview is given of the different types of quantum spin liquids and the models and theories used to describe them. We also provide a guide to the current status of experiments in relation to study quantum spin liquids, and to the diverse probes used therein.

  11. Frontiers of Theoretical Research on Shape Memory Alloys: A General Overview

    NASA Astrophysics Data System (ADS)

    Chowdhury, Piyas

    2018-03-01

    In this concise review, general aspects of modeling shape memory alloys (SMAs) are recounted. Different approaches are discussed under four general categories, namely, (a) macro-phenomenological, (b) micromechanical, (c) molecular dynamics, and (d) first principles models. Macro-phenomenological theories, stemming from empirical formulations depicting continuum elastic, plastic, and phase transformation, are primarily of engineering interest, whereby the performance of SMA-made components is investigated. Micromechanical endeavors are generally geared towards understanding microstructural phenomena within continuum mechanics such as the accommodation of straining due to phase change as well as role of precipitates. By contrast, molecular dynamics, being a more recently emerging computational technique, concerns attributes of discrete lattice structures, and thus captures SMA deformation mechanism by means of empirically reconstructing interatomic bonding forces. Finally, ab initio theories utilize quantum mechanical framework to peek into atomistic foundation of deformation, and can pave the way for studying the role of solid-sate effects. With specific examples, this paper provides concise descriptions of each category along with their relative merits and emphases.

  12. Microbiota-Brain-Gut Axis and Neurodegenerative Diseases.

    PubMed

    Quigley, Eamonn M M

    2017-10-17

    The purposes of this review were as follows: first, to provide an overview of the gut microbiota and its interactions with the gut and the central nervous system (the microbiota-gut-brain axis) in health, second, to review the relevance of this axis to the pathogenesis of neurodegenerative diseases, such as Parkinson's disease, and, finally, to assess the potential for microbiota-targeted therapies. Work on animal models has established the microbiota-gut-brain axis as a real phenomenon; to date, the evidence for its operation in man has been limited and has been confronted by considerable logistical challenges. Animal and translational models have incriminated a disturbed gut microbiota in a number of CNS disorders, including Parkinson's disease; data from human studies is scanty. While a theoretical basis can be developed for the use of microbiota-directed therapies in neurodegenerative disorders, support is yet to come from high-quality clinical trials. In theory, a role for the microbiota-gut-brain axis is highly plausible; clinical confirmation is awaited.

  13. [Communication on health and safety risk control in contemporary society: an interdisciplinary approach].

    PubMed

    Rangel-S, Maria Ligia

    2007-01-01

    This paper discusses communication as a technology for risk control with health and safety protection and promotion, within the context of a "risk society". As a component of Risk Analysis, risk communication is a technology that appears in risk literature, with well defined objectives, principles and models. These aspects are described and the difficulties are stressed, taking into consideration the multiple rationales related to risks in the culture and the many different aspects of risk regulation and control in the so-called "late modernity". Consideration is also given to the complexity of the communications process, guided by theoretical and methodological discussions in the field. In order to understand the true value of the communications field for risk control with health and safety protection and promotion, this paper also offers an overview of communication theories that support discussions of this matter, proposing a critical approach to models that include the dimensions of power and culture in the context of a capitalist society.

  14. Rapid climate change and the rate of adaptation: insight from experimental quantitative genetics.

    PubMed

    Shaw, Ruth G; Etterson, Julie R

    2012-09-01

    Evolution proceeds unceasingly in all biological populations. It is clear that climate-driven evolution has molded plants in deep time and within extant populations. However, it is less certain whether adaptive evolution can proceed sufficiently rapidly to maintain the fitness and demographic stability of populations subjected to exceptionally rapid contemporary climate change. Here, we consider this question, drawing on current evidence on the rate of plant range shifts and the potential for an adaptive evolutionary response. We emphasize advances in understanding based on theoretical studies that model interacting evolutionary processes, and we provide an overview of quantitative genetic approaches that can parameterize these models to provide more meaningful predictions of the dynamic interplay between genetics, demography and evolution. We outline further research that can clarify both the adaptive potential of plant populations as climate continues to change and the role played by ongoing adaptation in their persistence. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

  15. Rad4 recognition-at-a-distance: Physical basis of conformation-specific anomalous diffusion of DNA repair proteins.

    PubMed

    Kong, Muwen; Van Houten, Bennett

    2017-08-01

    Since Robert Brown's first observations of random walks by pollen particles suspended in solution, the concept of diffusion has been subject to countless theoretical and experimental studies in diverse fields from finance and social sciences, to physics and biology. Diffusive transport of macromolecules in cells is intimately linked to essential cellular functions including nutrient uptake, signal transduction, gene expression, as well as DNA replication and repair. Advancement in experimental techniques has allowed precise measurements of these diffusion processes. Mathematical and physical descriptions and computer simulations have been applied to model complicated biological systems in which anomalous diffusion, in addition to simple Brownian motion, was observed. The purpose of this review is to provide an overview of the major physical models of anomalous diffusion and corresponding experimental evidence on the target search problem faced by DNA-binding proteins, with an emphasis on DNA repair proteins and the role of anomalous diffusion in DNA target recognition. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Active Brownian Particles. From Individual to Collective Stochastic Dynamics

    NASA Astrophysics Data System (ADS)

    Romanczuk, P.; Bär, M.; Ebeling, W.; Lindner, B.; Schimansky-Geier, L.

    2012-03-01

    We review theoretical models of individual motility as well as collective dynamics and pattern formation of active particles. We focus on simple models of active dynamics with a particular emphasis on nonlinear and stochastic dynamics of such self-propelled entities in the framework of statistical mechanics. Examples of such active units in complex physico-chemical and biological systems are chemically powered nano-rods, localized patterns in reaction-diffusion system, motile cells or macroscopic animals. Based on the description of individual motion of point-like active particles by stochastic differential equations, we discuss different velocity-dependent friction functions, the impact of various types of fluctuations and calculate characteristic observables such as stationary velocity distributions or diffusion coefficients. Finally, we consider not only the free and confined individual active dynamics but also different types of interaction between active particles. The resulting collective dynamical behavior of large assemblies and aggregates of active units is discussed and an overview over some recent results on spatiotemporal pattern formation in such systems is given.

  17. Modelling jets, tori and flares in pulsar wind nebulae

    DOE PAGES

    Porth, Oliver; Buehler, Rolf; Olmi, Barbara; ...

    2017-03-22

    In this contribution we review the recent progress in the modelling of Pulsar Wind Nebulae (PWN). We start with a brief overview of the relevant physical processes in the magnetosphere, the wind-zone and the inflated nebula bubble. Radiative signatures and particle transport processes obtained from 3D simulations of PWN are discussed in the context of optical and X-ray observations. We then proceed to consider particle acceleration in PWN and elaborate on what can be learned about the particle acceleration from the dynamical structures called GwispsG observed in the Crab nebula. We also discuss recent observational and theoretical results of gamma-raymore » flares and the inner knot of the Crab nebula, which had been proposed as the emission site of the flares. Here, we extend the discussion to GeV flares from binary systems in which the pulsar wind interacts with the stellar wind from a companion star. The chapter concludes with a discussion of solved and unsolved problems posed by PWN.« less

  18. Glossary of access to health care and related concepts for low- and middle-income countries (LMICs): a critical review of international literature.

    PubMed

    Cabieses, Baltica; Bird, Philippa

    2014-01-01

    Access to health care is a multidimensional and complex concept. Achieving equitable access to care is an important goal for all countries, but particularly challenging in Low- and Middle-Income Countries (LMICs). Despite wide use of the concept of access, it continues to be defined and measured in very different ways. This glossary is a structured overview of key definitions for concepts related to access to health care, with special focus on the interpretation for LMICs. It aims to help people with interest in health service delivery to draw an overview and provide some pointers for further reading in both conceptual and empirical advances in access to health care in LMICs. This document is structured in five sections. The first introduces a general description of the concept of access to health care and its relevance to LMICs, the second displays the search conducted on access to health care for LMICs and the framework used for presentation of glossary terms, the third describes theoretical models most frequently used in the past when looking at access to health care in LMICs, the fourth is the list of terms, and the final section is a discussion of the most salient aspects of this critical review.

  19. The necessity of a theory of biology for tissue engineering: metabolism-repair systems.

    PubMed

    Ganguli, Suman; Hunt, C Anthony

    2004-01-01

    Since there is no widely accepted global theory of biology, tissue engineering and bioengineering lack a theoretical understanding of the systems being engineered. By default, tissue engineering operates with a "reductionist" theoretical approach, inherited from traditional engineering of non-living materials. Long term, that approach is inadequate, since it ignores essential aspects of biology. Metabolism-repair systems are a theoretical framework which explicitly represents two "functional" aspects of living organisms: self-repair and self-replication. Since repair and replication are central to tissue engineering, we advance metabolism-repair systems as a potential theoretical framework for tissue engineering. We present an overview of the framework, and indicate directions to pursue for extending it to the context of tissue engineering. We focus on biological networks, both metabolic and cellular, as one such direction. The construction of these networks, in turn, depends on biological protocols. Together these concepts may help point the way to a global theory of biology appropriate for tissue engineering.

  20. Modeling listeners' emotional response to music.

    PubMed

    Eerola, Tuomas

    2012-10-01

    An overview of the computational prediction of emotional responses to music is presented. Communication of emotions by music has received a great deal of attention during the last years and a large number of empirical studies have described the role of individual features (tempo, mode, articulation, timbre) in predicting the emotions suggested or invoked by the music. However, unlike the present work, relatively few studies have attempted to model continua of expressed emotions using a variety of musical features from audio-based representations in a correlation design. The construction of the computational model is divided into four separate phases, with a different focus for evaluation. These phases include the theoretical selection of relevant features, empirical assessment of feature validity, actual feature selection, and overall evaluation of the model. Existing research on music and emotions and extraction of musical features is reviewed in terms of these criteria. Examples drawn from recent studies of emotions within the context of film soundtracks are used to demonstrate each phase in the construction of the model. These models are able to explain the dominant part of the listeners' self-reports of the emotions expressed by music and the models show potential to generalize over different genres within Western music. Possible applications of the computational models of emotions are discussed. Copyright © 2012 Cognitive Science Society, Inc.

  1. An Educational Model for Hands-On Hydrology Education

    NASA Astrophysics Data System (ADS)

    AghaKouchak, A.; Nakhjiri, N.; Habib, E. H.

    2014-12-01

    This presentation provides an overview of a hands-on modeling tool developed for students in civil engineering and earth science disciplines to help them learn the fundamentals of hydrologic processes, model calibration, sensitivity analysis, uncertainty assessment, and practice conceptual thinking in solving engineering problems. The toolbox includes two simplified hydrologic models, namely HBV-EDU and HBV-Ensemble, designed as a complement to theoretical hydrology lectures. The models provide an interdisciplinary application-oriented learning environment that introduces the hydrologic phenomena through the use of a simplified conceptual hydrologic model. The toolbox can be used for in-class lab practices and homework assignments, and assessment of students' understanding of hydrological processes. Using this modeling toolbox, students can gain more insights into how hydrological processes (e.g., precipitation, snowmelt and snow accumulation, soil moisture, evapotranspiration and runoff generation) are interconnected. The educational toolbox includes a MATLAB Graphical User Interface (GUI) and an ensemble simulation scheme that can be used for teaching more advanced topics including uncertainty analysis, and ensemble simulation. Both models have been administered in a class for both in-class instruction and a final project, and students submitted their feedback about the toolbox. The results indicate that this educational software had a positive impact on students understanding and knowledge of hydrology.

  2. Could Masked Conceptual Primes Increase Recollection? The Subtleties of Measuring Recollection and Familiarity in Recognition Memory

    ERIC Educational Resources Information Center

    Taylor, Jason R.; Henson, Richard N.

    2012-01-01

    We begin with a theoretical overview of the concepts of recollection and familiarity, focusing, in the spirit of this special issue, on the important contributions made by Andrew Mayes. In particular, we discuss the issue of when the generation of semantically-related information in response to a retrieval cue might be experienced as recollection…

  3. Framing Teacher Preparation Research: An Overview of the Field, Part 1

    ERIC Educational Resources Information Center

    Cochran-Smith, Marilyn; Villegas, Ana Maria

    2015-01-01

    This is the first of a two-part article that aims to chart the contemporary landscape of research on teacher preparation and certification. It is based on a review of more than 1,500 studies published between 2000 and 2012. Part 1 provides information about how the review was conducted and describes the theoretical/analytic framework the authors…

  4. A Comparative Analysis of the Attitudes of Primary School Students and Teachers Regarding the Use of Games in Teaching

    ERIC Educational Resources Information Center

    Andic, Branko; Kadic, Srdan; Grujicic, Rade; Malidžan, Desanka

    2018-01-01

    This paper provides an overview of the attitudes of students and teachers toward the use of educational games in the teaching process. The study encompassed a didactic experiment, and adopted interviewing techniques and theoretical analysis. Likert distributions of attitudes to particular game types are presented in tables and the arithmetic means…

  5. Self-Esteem and Adjusting with Blindness: The Process of Responding to Life's Demands. Third Edition

    ERIC Educational Resources Information Center

    Tuttle, Dean W.; Tuttle, Naomi R.

    2004-01-01

    This new and expanded Third Edition analyzes blindness within the context of two overlapping theoretical constructs: the development of self-esteem and the process of adjusting to social and/or physical trauma. The book is divided into four sections. The first section, provides an overview of blindness and the essential background for subsequent…

  6. Choguita Rarámuri (Tarahumara) Language Description and Documentation: A Guide to the Deposited Collection and Associated Materials

    ERIC Educational Resources Information Center

    Caballero, Gabriela

    2017-01-01

    Choguita Rarámuri (Tarahumara) is a Uto-Aztecan language spoken in Northern Mexico of great typological, theoretical, and historical significance. This paper presents an overview and background of the Choguita Rarámuri language description and documentation project and provides a guide to the documentary collection emerging from this project. This…

  7. Michel Foucault on Education: A Preliminary Theoretical Overview

    ERIC Educational Resources Information Center

    Deacon, Roger

    2006-01-01

    Michel Foucault's work is already well-known in the field of education. What is not yet well-known is that Foucault's oeuvre as a whole incorporates within itself and offers for wider consumption a number of key educational themes. For purposes of clarity, these themes can be reduced to three, dealing with what might be called the past, present,…

  8. Aeropropulsion 1987. Session 2: Aeropropulsion Structures Research

    NASA Technical Reports Server (NTRS)

    1987-01-01

    Aeropropulsion systems present unique problems to the structural engineer. The extremes in operating temperatures, rotational effects, and behaviors of advanced material systems combine into complexities that require advances in many scientific disciplines involved in structural analysis and design procedures. This session provides an overview of the complexities of aeropropulsion structures and the theoretical, computational, and experimental research conducted to achieve the needed advances.

  9. Toward a Conceptual Framework of Culturally Relevant Pedagogy: An Overview of the Conceptual and Theoretical Literature

    ERIC Educational Resources Information Center

    Brown-Jeffy, Shelly; Cooper, Jewell E.

    2011-01-01

    The United States is a diverse country with constantly changing demographics. The noticeable shift in demographics is even more phenomenal among the school-aged population. The increase of ethnic-minority student presence is largely credited to the national growth of the Hispanic population, which exceeded the growth of all other ethnic minority…

  10. Language and "New" African Migration to South Africa: An Overview and Some Reflections on Theoretical Implications for Policy and Planning

    ERIC Educational Resources Information Center

    Orman, Jon

    2012-01-01

    This article examines the phenomenon of African migration to post-apartheid South Africa from a language-sociological perspective. Although the subject has been one largely neglected by language scholars, the handful of studies which have addressed the issue have yielded ethnographic data and raised questions of considerable significance for the…

  11. From Theorizing in the Ivory Tower to Creating Change with the People: Activist Research as a Framework for Collaborative Action

    ERIC Educational Resources Information Center

    Jones, Denisha

    2017-01-01

    This article provides an overview of activist research and how it is used in various field including anthropology, social movements, and education. It discusses the impetus for incorporating activism into theoretical frameworks and research methodologies and the distinct aspects of activist research. Youth participatory action research is examined…

  12. Evidence from Neurolinguistic Methodologies: Can It Actually Inform Linguistic/Language Acquisition Theories and Translate to Evidence-Based Applications?

    ERIC Educational Resources Information Center

    Roberts, Leah; González Alonso, Jorge; Pliatsikas, Christos; Rothman, Jason

    2018-01-01

    This special issue is a testament to the recent burgeoning interest by theoretical linguists, language acquisitionists and teaching practitioners in the neuroscience of language. It offers a highly valuable, state-of-the-art overview of the neurophysiological methods that are currently being applied to questions in the field of second language…

  13. Sorting the Wheat from the Chaff: What Makes for Good Evidence of Effectiveness in the Literature in Gifted Education?

    ERIC Educational Resources Information Center

    Callahan, Carolyn M.; Moon, Tonya R.

    2007-01-01

    To provide an overview of the specific components that must be considered when making decisions about research in the field of gifted education, the authors describe and evaluate the three types of evidence--speculative or anecdotal, theoretical, and empirical--commonly offered in the literature of the field. Empirical, or evidence-based, research…

  14. Fabrication and Investigation of Indium Nitride Possessing Ferromagnetic Properties

    NASA Astrophysics Data System (ADS)

    Khludkov, S. S.; Prudaev, I. A.; Tolbanov, O. P.

    2018-04-01

    An overview of the scientific literature since 2000 on InN doping with impurities giving it ferromagnetic properties and on the magnetic properties of InN is presented. According to theoretical and experimental studies, InN doped with transition metals and rare earth elements possesses ferromagnetic properties at temperatures above room temperature and is a material promising for spintronics.

  15. Forum Theatre and Parables: A Qualitative Field Experiment in a Seventh-Day Adventist Academy

    ERIC Educational Resources Information Center

    Freed, Dena Davis

    2012-01-01

    In this article, the author describes a qualitative field study designed to test the effectiveness of Forum Theatre (FT) as a cross-disciplinary approach to Biblical parabolic literature analysis for students enrolled in a Seventh-day Adventist (SDA) Academy. The author provides a brief overview of the theoretical framework of the study, the study…

  16. Issues in English Language Development. Proceedings of a Conference on Issues in English Language Development for Minority Language Education (Arlington, Virginia, July 24, 1985).

    ERIC Educational Resources Information Center

    InterAmerica Research Associates, Rosslyn, VA.

    Papers presented in this conference report include: "Overview of Theories of Language Learning and Acquisition" (Diane Larsen-Freeman); "A Theory of Strategy-Oriented Language Development" (Michael Canale); "Motivation, Intelligence, and Access: A Theoretical Framework for the Education of Minority Language Students" (Edward De Avila); "Second…

  17. "Politics is Ethics Done in Public": Exploring Linkages and Disjunctions between Citizenship Education and Character Education in England

    ERIC Educational Resources Information Center

    Kisby, Ben

    2017-01-01

    Purpose: This article explores linkages and disjunctions between citizenship education and character education in England. Approach: The article undertakes a theoretical discussion of what both forms of education are and involve, and a historical overview of their development over the past twenty years, utilising a wide range of primary and…

  18. Playing by the Rules: Researching, Teaching and Learning Sexual Ethics with Young Men in the Australian National Rugby League

    ERIC Educational Resources Information Center

    Albury, Kath; Carmody, Moira; Evers, Clifton; Lumby, Catharine

    2011-01-01

    In 2004, the Australian National Rugby League (NRL) commissioned the Playing By The Rules research project in response to allegations of sexual assault by members of a professional rugby league team. This article offers an overview of the theoretical and methodological approaches adopted by the team, and the subsequent workplace education…

  19. The Role of the Company in Generating Skills: The Learning Effects of Work Organisation. Germany. CEDEFOP Document.

    ERIC Educational Resources Information Center

    Grunewald, Uwe; Zimmer, Gerhard; Sauter, Edgar

    This document reports the findings of a 3-year study of company strategies and the training impact of labor organization in Germany. Among the topics discussed in the theoretical overview presented in section 1 are the following: the growing importance of learning in a working environment; Germany's continuing training "system" and…

  20. Towards representing human behavior and decision making in Earth system models - an overview of techniques and approaches

    NASA Astrophysics Data System (ADS)

    Müller-Hansen, Finn; Schlüter, Maja; Mäs, Michael; Donges, Jonathan F.; Kolb, Jakob J.; Thonicke, Kirsten; Heitzig, Jobst

    2017-11-01

    Today, humans have a critical impact on the Earth system and vice versa, which can generate complex feedback processes between social and ecological dynamics. Integrating human behavior into formal Earth system models (ESMs), however, requires crucial modeling assumptions about actors and their goals, behavioral options, and decision rules, as well as modeling decisions regarding human social interactions and the aggregation of individuals' behavior. Here, we review existing modeling approaches and techniques from various disciplines and schools of thought dealing with human behavior at different levels of decision making. We demonstrate modelers' often vast degrees of freedom but also seek to make modelers aware of the often crucial consequences of seemingly innocent modeling assumptions. After discussing which socioeconomic units are potentially important for ESMs, we compare models of individual decision making that correspond to alternative behavioral theories and that make diverse modeling assumptions about individuals' preferences, beliefs, decision rules, and foresight. We review approaches to model social interaction, covering game theoretic frameworks, models of social influence, and network models. Finally, we discuss approaches to studying how the behavior of individuals, groups, and organizations can aggregate to complex collective phenomena, discussing agent-based, statistical, and representative-agent modeling and economic macro-dynamics. We illustrate the main ingredients of modeling techniques with examples from land-use dynamics as one of the main drivers of environmental change bridging local to global scales.

  1. Magnetospheric disturbance effects on the Equatorial Ionization Anomaly (EIA) : an overview

    NASA Astrophysics Data System (ADS)

    Abdu, M. A.; Sobral, J. H. A.; de Paula, E. R.; Batista, I. S.

    1992-12-01

    The Equatorial lonization Anomaly (EIA) development can undergo drastic modification in the form of an anomalous occurrence at local times outside that of its quiet time development and/or inhibition/enhancement at local times of its normal occurrences. This happens for disturbed electrodynamic conditions of the global ionosphere-thermosphere-magnetosphere system, consequent upon the triggering of a magnetospheric storm event. Direct penetration to equatorial latitudes of the magnetospheric electric fields and the thermospheric disturbances involving winds, electric fields and composition changes produce significant alteration in the EIA morphology and dynamics. Results on statistical behaviour based on accumulated ground-based data sets, and those from recent theoretical modelling efforts and from satellite and ground-based observations, are reviewed. Some outstanding problems of the EIA response to magnetospheric disturbances that deserve attention in the coming years are pointed out.

  2. Atmospheric Ionizing Radiation and Human Exposure

    NASA Technical Reports Server (NTRS)

    Wilson, John W.; Mertens, Christopher J.; Goldhagen, Paul; Friedberg, W.; DeAngelis, G.; Clem, J. M.; Copeland, K.; Bidasaria, H. B.

    2005-01-01

    Atmospheric ionizing radiation is of interest, apart from its main concern of aircraft exposures, because it is a principal source of human exposure to radiations with high linear energy transfer (LET). The ionizing radiations of the lower atmosphere near the Earth s surface tend to be dominated by the terrestrial radioisotopes. especially along the coastal plain and interior low lands, and have only minor contributions from neutrons (11 percent). The world average is substantially larger but the high altitude cities especially have substantial contributions from neutrons (25 to 45 percent). Understanding the world distribution of neutron exposures requires an improved understanding of the latitudinal, longitudinal, altitude and spectral distribution that depends on local terrain and time. These issues are being investigated in a combined experimental and theoretical program. This paper will give an overview of human exposures and describe the development of improved environmental models.

  3. Atmospheric Ionizing Radiation and Human Exposure

    NASA Technical Reports Server (NTRS)

    Wilson, J. W.; Goldhagen, P.; Friedberg, W.; DeAngelis, G.; Clem, J. M.; Copeland, K.; Bidasaria, H. B.

    2004-01-01

    Atmospheric ionizing radiation is of interest, apart from its main concern of aircraft exposures, because it is a principal source of human exposure to radiations with high linear energy transfer (LET). The ionizing radiations of the lower atmosphere near the Earth s surface tend to be dominated by the terrestrial radioisotopes especially along the coastal plain and interior low lands and have only minor contributions from neutrons (11 percent). The world average is substantially larger but the high altitude cities especially have substantial contributions from neutrons (25 to 45 percent). Understanding the world distribution of neutron exposures requires an improved understanding of the latitudinal, longitudinal, altitude and spectral distribution that depends on local terrain and time. These issues are being investigated in a combined experimental and theoretical program. This paper will give an overview of human exposures and describe the development of improved environmental models.

  4. Bioinformatics in the Netherlands: the value of a nationwide community.

    PubMed

    van Gelder, Celia W G; Hooft, Rob W W; van Rijswijk, Merlijn N; van den Berg, Linda; Kok, Ruben G; Reinders, Marcel; Mons, Barend; Heringa, Jaap

    2017-09-15

    This review provides a historical overview of the inception and development of bioinformatics research in the Netherlands. Rooted in theoretical biology by foundational figures such as Paulien Hogeweg (at Utrecht University since the 1970s), the developments leading to organizational structures supporting a relatively large Dutch bioinformatics community will be reviewed. We will show that the most valuable resource that we have built over these years is the close-knit national expert community that is well engaged in basic and translational life science research programmes. The Dutch bioinformatics community is accustomed to facing the ever-changing landscape of data challenges and working towards solutions together. In addition, this community is the stable factor on the road towards sustainability, especially in times where existing funding models are challenged and change rapidly. © The Author 2017. Published by Oxford University Press.

  5. Evolutionary rescue: linking theory for conservation and medicine.

    PubMed

    Alexander, Helen K; Martin, Guillaume; Martin, Oliver Y; Bonhoeffer, Sebastian

    2014-12-01

    Evolutionary responses that rescue populations from extinction when drastic environmental changes occur can be friend or foe. The field of conservation biology is concerned with the survival of species in deteriorating global habitats. In medicine, in contrast, infected patients are treated with chemotherapeutic interventions, but drug resistance can compromise eradication of pathogens. These contrasting biological systems and goals have created two quite separate research communities, despite addressing the same central question of whether populations will decline to extinction or be rescued through evolution. We argue that closer integration of the two fields, especially of theoretical understanding, would yield new insights and accelerate progress on these applied problems. Here, we overview and link mathematical modelling approaches in these fields, suggest specific areas with potential for fruitful exchange, and discuss common ideas and issues for empirical testing and prediction.

  6. Optimal Information Processing in Biochemical Networks

    NASA Astrophysics Data System (ADS)

    Wiggins, Chris

    2012-02-01

    A variety of experimental results over the past decades provide examples of near-optimal information processing in biological networks, including in biochemical and transcriptional regulatory networks. Computing information-theoretic quantities requires first choosing or computing the joint probability distribution describing multiple nodes in such a network --- for example, representing the probability distribution of finding an integer copy number of each of two interacting reactants or gene products while respecting the `intrinsic' small copy number noise constraining information transmission at the scale of the cell. I'll given an overview of some recent analytic and numerical work facilitating calculation of such joint distributions and the associated information, which in turn makes possible numerical optimization of information flow in models of noisy regulatory and biochemical networks. Illustrating cases include quantification of form-function relations, ideal design of regulatory cascades, and response to oscillatory driving.

  7. SAW based systems for mobile communications satellites

    NASA Technical Reports Server (NTRS)

    Peach, R. C.; Miller, N.; Lee, M.

    1993-01-01

    Modern mobile communications satellites, such as INMARSAT 3, EMS, and ARTEMIS, use advanced onboard processing to make efficient use of the available L-band spectrum. In all of these cases, high performance surface acoustic wave (SAW) devices are used. SAW filters can provide high selectivity (100-200 kHz transition widths), combined with flat amplitude and linear phase characteristics; their simple construction and radiation hardness also makes them especially suitable for space applications. An overview of the architectures used in the above systems, describing the technologies employed, and the use of bandwidth switchable SAW filtering (BSSF) is given. The tradeoffs to be considered when specifying a SAW based system are analyzed, using both theoretical and experimental data. Empirical rules for estimating SAW filter performance are given. Achievable performance is illustrated using data from the INMARSAT 3 engineering model (EM) processors.

  8. The impact of recent advances in laboratory astrophysics on our understanding of the cosmos.

    PubMed

    Savin, D W; Brickhouse, N S; Cowan, J J; Drake, R P; Federman, S R; Ferland, G J; Frank, A; Gudipati, M S; Haxton, W C; Herbst, E; Profumo, S; Salama, F; Ziurys, L M; Zweibel, E G

    2012-03-01

    An emerging theme in modern astrophysics is the connection between astronomical observations and the underlying physical phenomena that drive our cosmos. Both the mechanisms responsible for the observed astrophysical phenomena and the tools used to probe such phenomena-the radiation and particle spectra we observe-have their roots in atomic, molecular, condensed matter, plasma, nuclear and particle physics. Chemistry is implicitly included in both molecular and condensed matter physics. This connection is the theme of the present report, which provides a broad, though non-exhaustive, overview of progress in our understanding of the cosmos resulting from recent theoretical and experimental advances in what is commonly called laboratory astrophysics. This work, carried out by a diverse community of laboratory astrophysicists, is increasingly important as astrophysics transitions into an era of precise measurement and high fidelity modeling.

  9. Ab initio treatment of fully open-shell medium-mass nuclei with the IM-SRG

    NASA Astrophysics Data System (ADS)

    Stroberg, Ragnar; Calci, Angelo; Holt, Jason; Navratil, Petr; Bogner, Scott; Hergert, Heiko; Roth, Robert; Schwenk, Achim

    2016-09-01

    The in-medium similarity renormalization group (IM-SRG) is a recently-developed theoretical many-body framework which - like the coupled cluster and the self-consistent Green's function approaches - allows for the treatment of medium-mass nuclei using interactions fit at the few-body level. I will give a brief overview of how the IM-SRG may be used to decouple a shell-model type valence space. I will then describe a recent development for the approximate treatment of residual 3N forces in the valence space which extends the reach of IM-SRG to essentially all medium-mass nuclei, and I will present some selected results spanning isotopic chains from beryllium (Z=4) to nickel (Z=28). Finally, I will discuss the consistent treatment of transition operators, highlighting the potential for future applications in electroweak physics.

  10. Weather and atmosphere observation with the ATOM all-sky camera

    NASA Astrophysics Data System (ADS)

    Jankowsky, Felix; Wagner, Stefan

    2015-03-01

    The Automatic Telescope for Optical Monitoring (ATOM) for H.E.S.S. is an 75 cm optical telescope which operates fully automated. As there is no observer present during observation, an auxiliary all-sky camera serves as weather monitoring system. This device takes an all-sky image of the whole sky every three minutes. The gathered data then undergoes live-analysis by performing astrometric comparison with a theoretical night sky model, interpreting the absence of stars as cloud coverage. The sky monitor also serves as tool for a meteorological analysis of the observation site of the the upcoming Cherenkov Telescope Array. This overview covers design and benefits of the all-sky camera and additionally gives an introduction into current efforts to integrate the device into the atmosphere analysis programme of H.E.S.S.

  11. Technology Program Management Model (TPMM) Overview

    DTIC Science & Technology

    2006-05-10

    1 1 “Secure the High Ground” Jeff Craver Project Manager Space and Missile Defense Technical Center Jeff.Craver@US.Army.Mil ff r r r j t r i il...f i l t r ff. r r . r . il UNCLASSIFIED UNCLASSIFIED Technology Program Management Model (TPMM) Overview 05-10-2006 Report Documentation Page Form...DATES COVERED 00-00-2006 to 00-00-2006 4. TITLE AND SUBTITLE Technology Program Management Model (TPMM) Overview 5a. CONTRACT NUMBER 5b. GRANT

  12. Integrating model behavior, optimization, and sensitivity/uncertainty analysis: overview and application of the MOUSE software toolbox

    USDA-ARS?s Scientific Manuscript database

    This paper provides an overview of the Model Optimization, Uncertainty, and SEnsitivity Analysis (MOUSE) software application, an open-source, Java-based toolbox of visual and numerical analysis components for the evaluation of environmental models. MOUSE is based on the OPTAS model calibration syst...

  13. Magnetars: the physics behind observations. A review.

    PubMed

    Turolla, R; Zane, S; Watts, A L

    2015-11-01

    Magnetars are the strongest magnets in the present universe and the combination of extreme magnetic field, gravity and density makes them unique laboratories to probe current physical theories (from quantum electrodynamics to general relativity) in the strong field limit. Magnetars are observed as peculiar, burst-active x-ray pulsars, the anomalous x-ray pulsars (AXPs) and the soft gamma repeaters (SGRs); the latter emitted also three 'giant flares', extremely powerful events during which luminosities can reach up to 10(47) erg s(-1) for about one second. The last five years have witnessed an explosion in magnetar research which has led, among other things, to the discovery of transient, or 'outbursting', and 'low-field' magnetars. Substantial progress has been made also on the theoretical side. Quite detailed models for explaining the magnetars' persistent x-ray emission, the properties of the bursts, the flux evolution in transient sources have been developed and confronted with observations. New insight on neutron star asteroseismology has been gained through improved models of magnetar oscillations. The long-debated issue of magnetic field decay in neutron stars has been addressed, and its importance recognized in relation to the evolution of magnetars and to the links among magnetars and other families of isolated neutron stars. The aim of this paper is to present a comprehensive overview in which the observational results are discussed in the light of the most up-to-date theoretical models and their implications. This addresses not only the particular case of magnetar sources, but the more fundamental issue of how physics in strong magnetic fields can be constrained by the observations of these unique sources.

  14. Economic Incentives for Cybersecurity: Using Economics to Design Technologies Ready for Deployment

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

    Vishik, Claire; Sheldon, Frederick T; Ott, David

    Cybersecurity practice lags behind cyber technology achievements. Solutions designed to address many problems may and do exist but frequently cannot be broadly deployed due to economic constraints. Whereas security economics focuses on the cost/benefit analysis and supply/demand, we believe that more sophisticated theoretical approaches, such as economic modeling, rarely utilized, would derive greater societal benefits. Unfortunately, today technologists pursuing interesting and elegant solutions have little knowledge of the feasibility for broad deployment of their results and cannot anticipate the influences of other technologies, existing infrastructure, and technology evolution, nor bring the solutions lifecycle into the equation. Additionally, potentially viable solutionsmore » are not adopted because the risk perceptions by potential providers and users far outweighs the economic incentives to support introduction/adoption of new best practices and technologies that are not well enough defined. In some cases, there is no alignment with redominant and future business models as well as regulatory and policy requirements. This paper provides an overview of the economics of security, reviewing work that helped to define economic models for the Internet economy from the 1990s. We bring forward examples of potential use of theoretical economics in defining metrics for emerging technology areas, positioning infrastructure investment, and building real-time response capability as part of software development. These diverse examples help us understand the gaps in current research. Filling these gaps will be instrumental for defining viable economic incentives, economic policies, regulations as well as early-stage technology development approaches, that can speed up commercialization and deployment of new technologies in cybersecurity.« less

  15. The second demographic transition: A concise overview of its development

    PubMed Central

    Lesthaeghe, Ron

    2014-01-01

    This article gives a concise overview of the theoretical development of the concept of the “second demographic transition” since it was coined in 1986, its components, and its applicability, first to European populations and subsequently also to non-European societies as well. Both the demographic and the societal contrasts between the first demographic transition (FDT) and the second demographic transition (SDT) are highlighted. Then, the major criticisms of the SDT theory are outlined, and these issues are discussed in the light of the most recent developments in Europe, the United States, the Far East, and Latin America. It turns out that three major SDT patterns have developed and that these evolutions are contingent on much older systems of kinship and family organization. PMID:25453112

  16. Divergences and estimating tight bounds on Bayes error with applications to multivariate Gaussian copula and latent Gaussian copula

    NASA Astrophysics Data System (ADS)

    Thelen, Brian J.; Xique, Ismael J.; Burns, Joseph W.; Goley, G. Steven; Nolan, Adam R.; Benson, Jonathan W.

    2017-04-01

    In Bayesian decision theory, there has been a great amount of research into theoretical frameworks and information- theoretic quantities that can be used to provide lower and upper bounds for the Bayes error. These include well-known bounds such as Chernoff, Battacharrya, and J-divergence. Part of the challenge of utilizing these various metrics in practice is (i) whether they are "loose" or "tight" bounds, (ii) how they might be estimated via either parametric or non-parametric methods, and (iii) how accurate the estimates are for limited amounts of data. In general what is desired is a methodology for generating relatively tight lower and upper bounds, and then an approach to estimate these bounds efficiently from data. In this paper, we explore the so-called triangle divergence which has been around for a while, but was recently made more prominent in some recent research on non-parametric estimation of information metrics. Part of this work is motivated by applications for quantifying fundamental information content in SAR/LIDAR data, and to help in this, we have developed a flexible multivariate modeling framework based on multivariate Gaussian copula models which can be combined with the triangle divergence framework to quantify this information, and provide approximate bounds on Bayes error. In this paper we present an overview of the bounds, including those based on triangle divergence and verify that under a number of multivariate models, the upper and lower bounds derived from triangle divergence are significantly tighter than the other common bounds, and often times, dramatically so. We also propose some simple but effective means for computing the triangle divergence using Monte Carlo methods, and then discuss estimation of the triangle divergence from empirical data based on Gaussian Copula models.

  17. Review: a conceptual model of perceived burden of informal caregivers for older persons with a severe functional psychiatric syndrome and concomitant problematic behaviour.

    PubMed

    Zegwaard, Marian I; Aartsen, Marja J; Cuijpers, Pim; Grypdonck, Mieke Hf

    2011-08-01

    This literature review aims to delineate the determinants of perceived burden by informal caregivers and provide insight into the interrelatedness between these determinants. Despite the attention given to the various determinants of perceived burden, their interrelatedness has not been unravelled. Insight into this interrelatedness is mandatory for the development of successful, complex, multivariate interventions to reduce perceived burden of informal caregivers. DESIGN; Systematic review. Four electronic databases, CINAHL, Embase psychiatry, Medline, Psychinfo and reference lists of selected articles, were searched. Publications between January 1985-2008 were included if they concerned mental illness, burden and care giving. Articles were selected according to predefined inclusion and exclusion criteria. The results of mostly descriptive, cross-sectional and univariate research and the more process-oriented results coming from qualitative burden research are organised in a process orientated conceptual scheme or model adapted from the stress-theoretical framework by Lazarus and Folkman. The model indicates that perceived burden must be understood through the individual appraisal of stressors and the availability and use of internal and external resources. Perceived burden is the outcome of multiple, clinically overlapping psychiatric problems, problematic behaviour and functional disabilities. So far, intervention programs to reduce perceived burden of informal caregivers have not devoted much attention to the interrelatedness of the origins of burden. The conceptual model provides an overview of the various determinants of perceived burden and a clear picture of the possible interrelatedness appears. This overview of the most important sources of burden helps to develop a complex, multivariate intervention that is comprehensive, long-term, individually tailored and has the flexibility to meet the dynamics of burden over time. Use of the conceptual model is crucial to professional nursing and the quality of support of informal caregivers. © 2011 Blackwell Publishing Ltd.

  18. Statistical Methods for Proteomic Biomarker Discovery based on Feature Extraction or Functional Modeling Approaches.

    PubMed

    Morris, Jeffrey S

    2012-01-01

    In recent years, developments in molecular biotechnology have led to the increased promise of detecting and validating biomarkers, or molecular markers that relate to various biological or medical outcomes. Proteomics, the direct study of proteins in biological samples, plays an important role in the biomarker discovery process. These technologies produce complex, high dimensional functional and image data that present many analytical challenges that must be addressed properly for effective comparative proteomics studies that can yield potential biomarkers. Specific challenges include experimental design, preprocessing, feature extraction, and statistical analysis accounting for the inherent multiple testing issues. This paper reviews various computational aspects of comparative proteomic studies, and summarizes contributions I along with numerous collaborators have made. First, there is an overview of comparative proteomics technologies, followed by a discussion of important experimental design and preprocessing issues that must be considered before statistical analysis can be done. Next, the two key approaches to analyzing proteomics data, feature extraction and functional modeling, are described. Feature extraction involves detection and quantification of discrete features like peaks or spots that theoretically correspond to different proteins in the sample. After an overview of the feature extraction approach, specific methods for mass spectrometry ( Cromwell ) and 2D gel electrophoresis ( Pinnacle ) are described. The functional modeling approach involves modeling the proteomic data in their entirety as functions or images. A general discussion of the approach is followed by the presentation of a specific method that can be applied, wavelet-based functional mixed models, and its extensions. All methods are illustrated by application to two example proteomic data sets, one from mass spectrometry and one from 2D gel electrophoresis. While the specific methods presented are applied to two specific proteomic technologies, MALDI-TOF and 2D gel electrophoresis, these methods and the other principles discussed in the paper apply much more broadly to other expression proteomics technologies.

  19. AQMEII Phase 2: Overview and WRF/CMAQ Application over North America

    EPA Science Inventory

    In this study, we provide an overview of the second phase of the Air Quality Model Evaluation International Initiative (AQMEII). Activities in this phase are focused on the application and evaluation of coupled meteorologychemistry models. Participating modeling systems are being...

  20. An Overview of the Human Systems Integration Division

    NASA Technical Reports Server (NTRS)

    Gore, Brian F.

    2015-01-01

    This presentation will provide an overview of the Human Systems Integration Division, and will highlight some of the human performance modeling efforts undertaken in previously presented MIDAS human performance modeling efforts.

  1. Food-chain contamination evaluations in ecological risk assessments

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

    Linder, G.

    Food-chain models have become increasingly important within the ecological risk assessment process. This is the case particularly when acute effects are not readily apparent, or the contaminants of concern are not readily detoxified, have a high likelihood for partitioning into lipids, or have specific target organs or tissues that may increase their significance in evaluating their potential adverse effects. An overview of food-chain models -- conceptual, theoretical, and empirical -- will be considered through a series of papers that will focus on their application within the ecological risk assessment process. Whether a food-chain evaluation is being developed to address relativelymore » simple questions related to chronic effects of toxicants on target populations, or whether a more complex food-web model is being developed to address questions related to multiple-trophic level transfers of toxicants, the elements within the food chain contamination evaluation can be generalized to address the mechanisms of toxicant accumulation in individual organisms. This can then be incorporated into more elaborate models that consider these organismal-level processes within the context of a species life-history or community-level responses that may be associated with long-term exposures.« less

  2. An overview of bioinformatics methods for modeling biological pathways in yeast.

    PubMed

    Hou, Jie; Acharya, Lipi; Zhu, Dongxiao; Cheng, Jianlin

    2016-03-01

    The advent of high-throughput genomics techniques, along with the completion of genome sequencing projects, identification of protein-protein interactions and reconstruction of genome-scale pathways, has accelerated the development of systems biology research in the yeast organism Saccharomyces cerevisiae In particular, discovery of biological pathways in yeast has become an important forefront in systems biology, which aims to understand the interactions among molecules within a cell leading to certain cellular processes in response to a specific environment. While the existing theoretical and experimental approaches enable the investigation of well-known pathways involved in metabolism, gene regulation and signal transduction, bioinformatics methods offer new insights into computational modeling of biological pathways. A wide range of computational approaches has been proposed in the past for reconstructing biological pathways from high-throughput datasets. Here we review selected bioinformatics approaches for modeling biological pathways inS. cerevisiae, including metabolic pathways, gene-regulatory pathways and signaling pathways. We start with reviewing the research on biological pathways followed by discussing key biological databases. In addition, several representative computational approaches for modeling biological pathways in yeast are discussed. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  3. Understanding Rasch Measurement: Rasch Models Overview.

    ERIC Educational Resources Information Center

    Wright, Benjamin D.; Mok, Magdalena

    2000-01-01

    Presents an overview of Rasch measurement models that begins with a conceptualization of continuous experiences often captured as discrete observations. Discusses the mathematical properties of the Rasch family of models that allow the transformation of discrete deterministic counts into continuous probabilistic abstractions. Also discusses six of…

  4. NEMS - National Energy Modeling System: An Overview

    EIA Publications

    2009-01-01

    The National Energy Modeling System: An Overview 2009 a summary description of NEMS and each of its components. NEMS is a computer-based, energy-economy modeling system of energy markets for the midterm period through 2030. The NEMS is used to produce the Annual Energy Outlook.

  5. Factors affecting physicians' use of a dedicated overview interface in an electronic health record: The importance of standard information and standard documentation.

    PubMed

    Jensen, Lotte Groth; Bossen, Claus

    2016-03-01

    It remains a continual challenge to present information in user interfaces in large IT systems to support overview in the best possible way. We here examine how an electronic health record (EHR) supports the creation of overview among hospital physicians with a particular focus on the use of an interface designed to provide clinicians with a patient information overview. The overview interface integrates information flexibly from diverse places in the EHR and presents this information in one screen display. Our study revealed widespread non-use of the overview interface. We explore the reasons for its use and non-use. We conducted exploratory ethnographic fieldwork among physicians in two hospitals and gathered statistical data on their use of the overview interface. From the quantitative data, we identified where the interface was used most and conducted 18 semi-structured, open-ended interviews framed by the theoretical framework and the findings of the initial ethnographic fieldwork. We interviewed both physicians and employees from the IT units in different hospitals. We then analysed notes from the ethnographic fieldwork and the interviews and ordered these into themes forming the basis for the presentation of findings. The overview interface was most used in departments or situations where the problem at hand and the need for information could be standardized-in particular, in anesthesiological departments and outpatient clinics. However, departments with complex and long patient histories did not make much use of the overview interface. Design and layout were not mentioned as decisive factors affecting its use or non-use. Many physicians questioned the completeness of data in the overview interface-either because they were skeptical about the hospital's or the department's documentation practices, or because they could not recognize the structure of the interface. This uncertainty discouraged physicians from using the overview interface. Dedicating a specific function or interface to supporting overview works best where information needs can be standardized. The narrative and contextual nature of creating clinical overview is unlikely to be optimally supported by using the overview interface alone. The use of these kinds of interfaces requires trust in data completeness and other clinicians' and administrative staff's documentation practices, as well as an understanding of the underlying structure of the EHR and how information is filtered when data are aggregated for the interface. Copyright © 2015. Published by Elsevier Ireland Ltd.

  6. QM/MM investigations of organic chemistry oriented questions.

    PubMed

    Schmidt, Thomas C; Paasche, Alexander; Grebner, Christoph; Ansorg, Kay; Becker, Johannes; Lee, Wook; Engels, Bernd

    2014-01-01

    About 35 years after its first suggestion, QM/MM became the standard theoretical approach to investigate enzymatic structures and processes. The success is due to the ability of QM/MM to provide an accurate atomistic picture of enzymes and related processes. This picture can even be turned into a movie if nuclei-dynamics is taken into account to describe enzymatic processes. In the field of organic chemistry, QM/MM methods are used to a much lesser extent although almost all relevant processes happen in condensed matter or are influenced by complicated interactions between substrate and catalyst. There is less importance for theoretical organic chemistry since the influence of nonpolar solvents is rather weak and the effect of polar solvents can often be accurately described by continuum approaches. Catalytic processes (homogeneous and heterogeneous) can often be reduced to truncated model systems, which are so small that pure quantum-mechanical approaches can be employed. However, since QM/MM becomes more and more efficient due to the success in software and hardware developments, it is more and more used in theoretical organic chemistry to study effects which result from the molecular nature of the environment. It is shown by many examples discussed in this review that the influence can be tremendous, even for nonpolar reactions. The importance of environmental effects in theoretical spectroscopy was already known. Due to its benefits, QM/MM can be expected to experience ongoing growth for the next decade.In the present chapter we give an overview of QM/MM developments and their importance in theoretical organic chemistry, and review applications which give impressions of the possibilities and the importance of the relevant effects. Since there is already a bunch of excellent reviews dealing with QM/MM, we will discuss fundamental ingredients and developments of QM/MM very briefly with a focus on very recent progress. For the applications we follow a similar strategy.

  7. Overview of RICOR's reliability theoretical analysis, accelerated life demonstration test results and verification by field data

    NASA Astrophysics Data System (ADS)

    Vainshtein, Igor; Baruch, Shlomi; Regev, Itai; Segal, Victor; Filis, Avishai; Riabzev, Sergey

    2018-05-01

    The growing demand for EO applications that work around the clock 24hr/7days a week, such as in border surveillance systems, emphasizes the need for a highly reliable cryocooler having increased operational availability and optimized system's Integrated Logistic Support (ILS). In order to meet this need, RICOR developed linear and rotary cryocoolers which achieved successfully this goal. Cryocoolers MTTF was analyzed by theoretical reliability evaluation methods, demonstrated by normal and accelerated life tests at Cryocooler level and finally verified by field data analysis derived from Cryocoolers operating at system level. The following paper reviews theoretical reliability analysis methods together with analyzing reliability test results derived from standard and accelerated life demonstration tests performed at Ricor's advanced reliability laboratory. As a summary for the work process, reliability verification data will be presented as a feedback from fielded systems.

  8. Research Directions in Real-Time Systems.

    DTIC Science & Technology

    1996-09-01

    This report summarizes a survey of published research in real time systems . Material is presented that provides an overview of the topic, focusing on...communications protocols and scheduling techniques. It is noted that real - time systems deserve special attention separate from other areas because of...formal tools for design and analysis of real - time systems . The early work on applications as well as notable theoretical advances are summarized

  9. Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (75th, Montreal, Quebec, Canada, August 5-8, 1992). Part XI: Advertising.

    ERIC Educational Resources Information Center

    Association for Education in Journalism and Mass Communication.

    The Advertising section of the proceedings contains the following 16 papers: "Ethics of Advertising Practitioners: An Explanation Based on a Classical Theoretical Framework" (Cornelius B. Pratt and E. Lincoln James); "Sex Roles in Frightening Film Newspaper Advertisements: An Overview of the Past 50 Years" (Melissa M. Spirek);…

  10. The Emperor Has No Clothes: Teaching about Race and Racism to People Who Don't Want to Know

    ERIC Educational Resources Information Center

    Okun, Tema Jon

    2010-01-01

    "The Emperor Has No Clothes: Teaching About Race and Racism to People Who Don't Want to Know" is designed to offer both practical and theoretical grounding for leaders and teachers interested in effectively addressing racism as well as other oppressive constructs. The dissertation offers an overview of the role of western culture in maintaining…

  11. Planetary atmospheric physics and solar physics research

    NASA Technical Reports Server (NTRS)

    1973-01-01

    An overview is presented on current and planned research activities in the major areas of solar physics, planetary atmospheres, and space astronomy. The approach to these unsolved problems involves experimental techniques, theoretical analysis, and the use of computers to analyze the data from space experiments. The point is made that the research program is characterized by each activity interacting with the other activities in the laboratory.

  12. Elicited Imitation: A Vehicle for Assessing the Language Functioning Level of Echolalic Autistic Children. Final Report 53.8.

    ERIC Educational Resources Information Center

    Fritsch, Gudrun

    The booklet discusses and reports on a study of elicited imitation as a vehicle for assessing the language-functioning level of echolalic autistic children. An historical overview is presented of the diagnosis of early infantile autism. The question of whether or not early infantile autism is a distinct syndrome is addressed. The theoretical and…

  13. The Use of Brain Electrophysiology Techniques To Study Language: A Basic Guide for the Beginning Consumer of Electrophysiology Information.

    ERIC Educational Resources Information Center

    Molfese, Dennis L.; Molfese, Victoria J.; Kelly, Spencer

    2001-01-01

    This article provides an introduction to the use of event-related potential (ERP) approaches to study language processes. First, a brief history of the emergence of this technology is presented, followed by definitions, a theoretical overview, and a practical guide to conducting ERP studies. Examples of language studies that use this technique are…

  14. Revista de Documentacao de Estudos em Liguistica Teorica e Aplicada, 1998 (Journal of Documentary Studies in Linguistic Theory and Application, 1998).

    ERIC Educational Resources Information Center

    Barbara, Leila, Ed.; Rajagopalan, Kanavillil, Ed.

    1998-01-01

    This document consists of three issues of DELTA, comprising its entire output for 1998. DELTA is a journal of theoretical and applied linguistics and covers a wide variety of material related to language, speech, and education. The journal publishes only original research and ideas presented in the form of articles, debates, squibs, overviews,…

  15. The effects of work-related values on communication between R and D groups, part 1. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Douds, C. F.

    1970-01-01

    The research concerned with the liaison, interface, coupling, and technology transfer processes that occur in research and development is reported. Overviews of the functions of communication and coupling in the R and D processes, and the theoretical considerations of coupling, communication, and values are presented along with descriptions of the field research program and the instrumentation.

  16. GEOS-2 refraction program summary document. [ionospheric and tropospheric propagation errors in satellite tracking instruments

    NASA Technical Reports Server (NTRS)

    Mallinckrodt, A. J.

    1977-01-01

    Data from an extensive array of collocated instrumentation at the Wallops Island test facility were intercompared in order to (1) determine the practical achievable accuracy limitations of various tropospheric and ionospheric correction techniques; (2) examine the theoretical bases and derivation of improved refraction correction techniques; and (3) estimate internal systematic and random error levels of the various tracking stations. The GEOS 2 satellite was used as the target vehicle. Data were obtained regarding the ionospheric and tropospheric propagation errors, the theoretical and data analysis of which was documented in some 30 separate reports over the last 6 years. An overview of project results is presented.

  17. Integrating Motivational Interviewing and Brief Behavioral Activation Therapy: Theoretical and Practical Considerations

    PubMed Central

    Balán, Iván C.; Lejuez, C. W.; Hoffer, Marcela; Blanco, Carlos

    2017-01-01

    Behavioral Activation and specifically the Brief Behavioral Activation Therapy for Depression (BATD) has a strong record of empirical support but its focus on practical out of session activation-based assignments can lead to poor levels of adherence if efforts to enhance motivation are not prioritized. Towards this end, this manuscript describes the assimilative integration of Motivational Interviewing (MI) and BATD to improve clinical outcomes by integrating MI's focus on building and maintaining motivation to change into BATD. The manuscript provides an overview of MI and BATD, theoretical issue raised in integrating the two approaches, and examples of how this integration results in a nondirective and motivation-focused approach to conducting BATD. PMID:29151779

  18. Results of the Lake Michigan Mass Balance Project: Atrazine Modeling Report

    EPA Science Inventory

    This report covers an overview of chemical properties, measurements in air and water, model construct and assumptions, and results of mathematical mass balance modeling of the herbicide atrazine in the Lake Michigan basin. Within the context of the mass balance, an overview of a...

  19. “AQMEII Phase 2: Overview and WRF/CMAQ Application over North America”.

    EPA Science Inventory

    This presentation provides an overview of the second phase of the Air Quality Model Evaluation International Initative (AQMEII). Activities in this phase are focused on the application and evaluation of coupled meteorology-chemistry models to assess how well these models can simu...

  20. “Overview and Evaluation of AQMEII Phase 2 Coupled Simulations over North America”

    EPA Science Inventory

    This presentation provides an overview of the second phase of the Air Quality Model Evaluation International Initative (AQMEII). Activities in this phase are focused on the application and evaluation of coupled meteorology-chemistry models to assess how well these models can simu...

  1. Interreligious education: Conceptualising a needs assessment framework for curriculum design in plural societies (with special reference to Mauritius)

    NASA Astrophysics Data System (ADS)

    Maudarbux, Mohammad Belall

    2016-08-01

    The growing debate on intercultural and interreligious dialogue has one major drawback: how to translate academic and theoretical contributions into practical tools for educators and policy makers. This paper aims to fill this gap by presenting a transferable "needs assessment model" based on five criteria and twenty measurable indicators of interreligious relations within a country. Using the example of Mauritius, a densely multilingual and multireligious country, the paper gives an inside view of the preparations which led to the launch of an innovative "Peace and Interfaith Studies" course at the University of Mauritius in 2010. The author was himself involved first as a curriculum consultant and then as a project manager of this course at the Council of Religions in Mauritius. After clarifying the differences between related concepts like multicultural education, intercultural education and religious education, the author defines "interreligious education" as being distinct from all of the above. The paper then proceeds to explain the rationale of interreligious education, followed by the identification of the critical factors which affect curriculum design and policy making. It uses these factors to highlight how each of them operates in Mauritius to create a web of complexity which makes interreligious education extremely volatile. This is followed by an overview of religious education in the Mauritian schooling system, an overview of the needs assessment framework and a description of the innovative "Peace and Interfaith Studies" course. The paper ends with a brief discussion of the main challenges of this model.

  2. More Than Words: The Role of Multiword Sequences in Language Learning and Use.

    PubMed

    Christiansen, Morten H; Arnon, Inbal

    2017-07-01

    The ability to convey our thoughts using an infinite number of linguistic expressions is one of the hallmarks of human language. Understanding the nature of the psychological mechanisms and representations that give rise to this unique productivity is a fundamental goal for the cognitive sciences. A long-standing hypothesis is that single words and rules form the basic building blocks of linguistic productivity, with multiword sequences being treated as units only in peripheral cases such as idioms. The new millennium, however, has seen a shift toward construing multiword linguistic units not as linguistic rarities, but as important building blocks for language acquisition and processing. This shift-which originated within theoretical approaches that emphasize language learning and use-has far-reaching implications for theories of language representation, processing, and acquisition. Incorporating multiword units as integral building blocks blurs the distinction between grammar and lexicon; calls for models of production and comprehension that can accommodate and give rise to the effect of multiword information on processing; and highlights the importance of such units to learning. In this special topic, we bring together cutting-edge work on multiword sequences in theoretical linguistics, first-language acquisition, psycholinguistics, computational modeling, and second-language learning to present a comprehensive overview of the prominence and importance of such units in language, their possible role in explaining differences between first- and second-language learning, and the challenges the combined findings pose for theories of language. Copyright © 2017 Cognitive Science Society, Inc.

  3. Estimating evapotranspiration and drought stress with ground-based thermal remote sensing in agriculture: a review.

    PubMed

    Maes, W H; Steppe, K

    2012-08-01

    As evaporation of water is an energy-demanding process, increasing evapotranspiration rates decrease the surface temperature (Ts) of leaves and plants. Based on this principle, ground-based thermal remote sensing has become one of the most important methods for estimating evapotranspiration and drought stress and for irrigation. This paper reviews its application in agriculture. The review consists of four parts. First, the basics of thermal remote sensing are briefly reviewed. Second, the theoretical relation between Ts and the sensible and latent heat flux is elaborated. A modelling approach was used to evaluate the effect of weather conditions and leaf or vegetation properties on leaf and canopy temperature. Ts increases with increasing air temperature and incoming radiation and with decreasing wind speed and relative humidity. At the leaf level, the leaf angle and leaf dimension have a large influence on Ts; at the vegetation level, Ts is strongly impacted by the roughness length; hence, by canopy height and structure. In the third part, an overview of the different ground-based thermal remote sensing techniques and approaches used to estimate drought stress or evapotranspiration in agriculture is provided. Among other methods, stress time, stress degree day, crop water stress index (CWSI), and stomatal conductance index are discussed. The theoretical models are used to evaluate the performance and sensitivity of the most important methods, corroborating the literature data. In the fourth and final part, a critical view on the future and remaining challenges of ground-based thermal remote sensing is presented.

  4. The Elaborated Environmental Stress Hypothesis as a Framework for Understanding the Association Between Motor Skills and Internalizing Problems: A Mini-Review

    PubMed Central

    Mancini, Vincent O.; Rigoli, Daniela; Cairney, John; Roberts, Lynne D.; Piek, Jan P.

    2016-01-01

    Poor motor skills have been shown to be associated with a range of psychosocial issues, including internalizing problems (anxiety and depression). While well-documented empirically, our understanding of why this relationship occurs remains theoretically underdeveloped. The Elaborated Environmental Stress Hypothesis by Cairney et al. (2013) provides a promising framework that seeks to explain the association between motor skills and internalizing problems, specifically in children with developmental coordination disorder (DCD). The framework posits that poor motor skills predispose the development of internalizing problems via interactions with intermediary environmental stressors. At the time the model was proposed, limited direct evidence was available to support or refute the framework. Several studies and developments related to the framework have since been published. This mini-review seeks to provide an up-to-date overview of recent developments related to the Elaborated Environmental Stress Hypothesis. We briefly discuss the past research that led to its development, before moving to studies that have investigated the framework since it was proposed. While originally developed within the context of DCD in childhood, recent developments have found support for the model in community samples. Through the reviewed literature, this article provides support for the Elaborated Environmental Stress Hypothesis as a promising theoretical framework that explains the psychosocial correlates across the broader spectrum of motor ability. However, given its recent conceptualization, ongoing evaluation of the Elaborated Environmental Stress Hypothesis is recommended. PMID:26941690

  5. Surface-screening mechanisms in ferroelectric thin films and their effect on polarization dynamics and domain structures

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

    Kalinin, Sergei V.; Kim, Yunseok; Fong, Dillon D.

    For over 70 years, ferroelectric materials have been one of the central research topics for condensed matter physics and material science, an interest driven both by fundamental science and applications. However, ferroelectric surfaces, the key component of ferroelectric films and nanostructures, still present a significant theoretical and even conceptual challenge. Indeed, stability of ferroelectric phase per se necessitates screening of polarization charge. At surfaces, this can lead to coupling between ferroelectric and semiconducting properties of material, or with surface (electro) chemistry, going well beyond classical models applicable for ferroelectric interfaces. In this review, we summarize recent studies of surface-screening phenomenamore » in ferroelectrics. We provide a brief overview of the historical understanding of the physics of ferroelectric surfaces, and existing theoretical models that both introduce screening mechanisms and explore the relationship between screening and relevant aspects of ferroelectric functionalities starting from phase stability itself. Given that the majority of ferroelectrics exist in multiple-domain states, we focus on local studies of screening phenomena using scanning probe microscopy techniques. We discuss recent studies of static and dynamic phenomena on ferroelectric surfaces, as well as phenomena observed under lateral transport, light, chemical, and pressure stimuli. We also note that the need for ionic screening renders polarization switching a coupled physical-electrochemical process and discuss the non-trivial phenomena such as chaotic behavior during domain switching that stem from this.« less

  6. Application of tabu search to deterministic and stochastic optimization problems

    NASA Astrophysics Data System (ADS)

    Gurtuna, Ozgur

    During the past two decades, advances in computer science and operations research have resulted in many new optimization methods for tackling complex decision-making problems. One such method, tabu search, forms the basis of this thesis. Tabu search is a very versatile optimization heuristic that can be used for solving many different types of optimization problems. Another research area, real options, has also gained considerable momentum during the last two decades. Real options analysis is emerging as a robust and powerful method for tackling decision-making problems under uncertainty. Although the theoretical foundations of real options are well-established and significant progress has been made in the theory side, applications are lagging behind. A strong emphasis on practical applications and a multidisciplinary approach form the basic rationale of this thesis. The fundamental concepts and ideas behind tabu search and real options are investigated in order to provide a concise overview of the theory supporting both of these two fields. This theoretical overview feeds into the design and development of algorithms that are used to solve three different problems. The first problem examined is a deterministic one: finding the optimal servicing tours that minimize energy and/or duration of missions for servicing satellites around Earth's orbit. Due to the nature of the space environment, this problem is modeled as a time-dependent, moving-target optimization problem. Two solution methods are developed: an exhaustive method for smaller problem instances, and a method based on tabu search for larger ones. The second and third problems are related to decision-making under uncertainty. In the second problem, tabu search and real options are investigated together within the context of a stochastic optimization problem: option valuation. By merging tabu search and Monte Carlo simulation, a new method for studying options, Tabu Search Monte Carlo (TSMC) method, is developed. The theoretical underpinnings of the TSMC method and the flow of the algorithm are explained. Its performance is compared to other existing methods for financial option valuation. In the third, and final, problem, TSMC method is used to determine the conditions of feasibility for hybrid electric vehicles and fuel cell vehicles. There are many uncertainties related to the technologies and markets associated with new generation passenger vehicles. These uncertainties are analyzed in order to determine the conditions in which new generation vehicles can compete with established technologies.

  7. Assessing Academic Risk of Student-Athletes: Applicability of the NCAA Graduation Risk Overview Model to GPA

    ERIC Educational Resources Information Center

    Johnson, James

    2013-01-01

    In an effort to standardize academic risk assessment, the NCAA developed the graduation risk overview (GRO) model. Although this model was designed to assess graduation risk, its ability to predict grade-point average (GPA) remained unknown. Therefore, 134 individual risk assessments were made to determine GRO model effectiveness in the…

  8. The MVP Model: Overview and Application

    ERIC Educational Resources Information Center

    Keller, John M.

    2017-01-01

    This chapter contains an overview of the MVP model that is used as a basis for the other chapters in this issue. It also contains a description of key steps in the ARCS-V design process that is derived from the MVP model and a summary of a design-based research study illustrating the application of the ARCS-V model.

  9. An Overview of Markov Chain Methods for the Study of Stage-Sequential Developmental Processes

    ERIC Educational Resources Information Center

    Kapland, David

    2008-01-01

    This article presents an overview of quantitative methodologies for the study of stage-sequential development based on extensions of Markov chain modeling. Four methods are presented that exemplify the flexibility of this approach: the manifest Markov model, the latent Markov model, latent transition analysis, and the mixture latent Markov model.…

  10. “Overview and Evaluation of AQMEII Phase 2 Coupled ...

    EPA Pesticide Factsheets

    This presentation provides an overview of the second phase of the Air Quality Model Evaluation International Initative (AQMEII). Activities in this phase are focused on the application and evaluation of coupled meteorology-chemistry models to assess how well these models can simulate the observed spatio-temporal variability in the optical and radiative characteristics of atmospheric aerosols and associated feedbacks among aerosols, radiation, clouds, and precipitation. To this end, these modeling systems are being applied for annual simulations over both North America and Europe using common emissions and boundary conditions for all modeling groups. We present an overview of these common input datasets, observational datasets for model evaluation, and case studies for diagnostic evaluation. In addition to this overview, we also present results from AQMEII Phase 2 WRF/CMAQ simulations over North America for both 2006 and 2010. The time period between 2006 and 2010 was characterized by a 35% reduction in U.S. SO2 emissions and 20% reduction in U.S. NOx emissions, providing an opportunity for dynamic model evaluation by investigating the impact of emission reductions on ambient concentrations as well as aerosol/radiation feedback effects. We present results of this dynamic evaluation. We also present a brief overview of initial results from WRF-Chem and GEM-MACH simulations performed for the same time period and domain as part of AQMEII Phase 2. The National Exposu

  11. Current Research at the University of Chicago Enrico Fermi Institute and James Franck Institute

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

    Swordy, Simon

    2009-03-04

    These talks will give an overview of physics research at the University of Chicago centered in two research institutes. The Enrico Fermi Institute pursues research in some core areas of the physical sciences. These include cosmology, particle physics, theoretical physics, particle astrophysics, and cosmochemistry. The EFI talk will focus on some examples of these activities which together will provide a broad overview of EFI science. Research at the James Franck Institute centers on the intersection between physics, chemistry and materials science, with the aim to unravel the complex connections between structure and dynamics in condensed matter systems. The JFI ismore » also home to the Chicago Materials Research Science and Engineering Center. The JFI talk will provide highlights of current projects by JFI members.« less

  12. Current Research at the University of Chicago Enrico Fermi Institute and James Franck Institute

    ScienceCinema

    Swordy, Simon

    2017-12-22

    These talks will give an overview of physics research at the University of Chicago centered in two research institutes. The Enrico Fermi Institute pursues research in some core areas of the physical sciences. These include cosmology, particle physics, theoretical physics, particle astrophysics, and cosmochemistry. The EFI talk will focus on some examples of these activities which together will provide a broad overview of EFI science. Research at the James Franck Institute centers on the intersection between physics, chemistry and materials science, with the aim to unravel the complex connections between structure and dynamics in condensed matter systems. The JFI is also home to the Chicago Materials Research Science and Engineering Center. The JFI talk will provide highlights of current projects by JFI members.

  13. Plume splitting and oscillatory behavior in transient plasmas generated by high-fluence laser ablation in vacuum

    NASA Astrophysics Data System (ADS)

    Focsa, C.; Gurlui, S.; Nica, P.; Agop, M.; Ziskind, M.

    2017-12-01

    We present a short overview of studies performed in our research groups over the last decade on the characterization of transient plasma plumes generated by laser ablation in various temporal regimes, from nanosecond to femtosecond. New results are also presented along with this overview, both being placed in the context of similar studies performed by other investigators. Optical (fast gate intensified CCD camera imaging and space- and time-resolved emission spectroscopy) and electrical (mainly Langmuir probe) methods have been applied to experimentally explore the dynamics of the plasma plume and its constituents. Peculiar effects as plume splitting and sharpening or oscillations onset have been evidenced in vacuum at high laser fluence. New theoretical approaches have been developed to account for the experimental observations.

  14. How are self-rated health and diagnosed disease related to early or deferred retirement? A cross-sectional study of employees aged 55-64.

    PubMed

    Nilsson, Kerstin; Hydbom, Anna Rignell; Rylander, Lars

    2016-08-26

    More people will probably continue working into old age in the future due to the increased size of aging populations in many countries. We therefore need to know more about older workers' health in relation to their work situation and retirement. This study is a part of a theoretical development of older workers' situations. Older workers' situations are theoretically themed in nine areas by the authors of this study. The aims of the study were to investigate the relationship between: i) diagnosed disease and factors in older workers' situations, theoretically themed in nine areas; ii) self-rated health and factors in older workers' situations, theoretically themed in nine areas; iii) diagnosed disease and self-rated health; and iv) the relationships between these health measures and retirement. A questionnaire-based cross-sectional study, using logistic regression, with 1,756 health care personnel aged 55-64 years. The questionnaire used gave an overview of most different areas in the older workers' situations. There was a difference in the participants' frequency of objectively specified diagnosed disease and their subjectively experienced self-rated health. A bad self-rated health was related higher to early retirement than diagnosed diseases. In the multivariate model, having 'Diagnosed disease' was not significantly related to whether older workers thought they could not work beyond 65 years of age. A bad 'Self-rated health' was also more highly related to whether older workers thought they could not work beyond 65 years, than if the respondents stated that a 'Diagnosed disease is a hindrance in my daily work' in the multivariate model. This study showed an important difference between older workers' own experiences and the effect of their self-rated health and their diagnosed diseases. Subjective self-rated health seems to be more important to people's retirement planning than diagnosed disease. The most important factors affecting older workers' self-rated health was the degree to which they felt physically and mentally fatigued, their possibilities for revitalization, and issues of work satisfaction, age discrimination and attitudes of managers to them as seniors.

  15. Social anxiety and information processing biases: An integrated theoretical perspective.

    PubMed

    Peschard, Virginie; Philippot, Pierre

    2016-01-01

    Models of anxiety disorders posit that information processing biases towards threat may result from an imbalance between top-down attentional control processes and bottom-up attentional processes, such that anxiety could reduce the influence of the former and increase the influence of the latter. However, researchers have recently pointed to limitations of the top-down/bottom-up terminology and outlined the additional contribution of memory processes to attention guidance. The goal of this paper is to provide bridges between recent findings from cognitive psychology and anxiety disorders research. We first provide an integrative overview of the processes influencing the content of working memory, including the availability of attentional control, and the strengths of task goals, stimulus salience, selection history and long-term memory. We then illustrate the interest of this formulation to the study of information processing biases in anxiety disorders, with a specific focus on social anxiety.

  16. A fractal approach to dynamic inference and distribution analysis

    PubMed Central

    van Rooij, Marieke M. J. W.; Nash, Bertha A.; Rajaraman, Srinivasan; Holden, John G.

    2013-01-01

    Event-distributions inform scientists about the variability and dispersion of repeated measurements. This dispersion can be understood from a complex systems perspective, and quantified in terms of fractal geometry. The key premise is that a distribution's shape reveals information about the governing dynamics of the system that gave rise to the distribution. Two categories of characteristic dynamics are distinguished: additive systems governed by component-dominant dynamics and multiplicative or interdependent systems governed by interaction-dominant dynamics. A logic by which systems governed by interaction-dominant dynamics are expected to yield mixtures of lognormal and inverse power-law samples is discussed. These mixtures are described by a so-called cocktail model of response times derived from human cognitive performances. The overarching goals of this article are twofold: First, to offer readers an introduction to this theoretical perspective and second, to offer an overview of the related statistical methods. PMID:23372552

  17. Dynamics of the Final Stages of Terrestrial Planet Growth and the Formation of the Earth-Moon System

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.; Rivera, Eugenio J.; DeVincenzi, Donald (Technical Monitor)

    2000-01-01

    An overview of current theories of star and planet formation, with emphasis on terrestrial planet accretion and the formation of the Earth-Moon system is presented. These models predict that rocky planets should form around most single stars, although it is possible that in some cases such planets are lost to orbital decay within the protoplanetary disk. The frequency of formation of gas giant planets is more difficult to predict theoretically. Terrestrial planets are believed to grow via pairwise accretion until the spacing of planetary orbits becomes large enough that the configuration is stable for the age of the system. Giant impacts during the final stages of growth can produce large planetary satellites, such as Earth's Moon. Giant planets begin their growth like terrestrial planets, but they become massive enough that they are able to accumulate substantial amounts of gas before the protoplanetary disk dissipates.

  18. The emergence of spontaneous activity in neuronal cultures

    NASA Astrophysics Data System (ADS)

    Orlandi, J. G.; Alvarez-Lacalle, E.; Teller, S.; Soriano, J.; Casademunt, J.

    2013-01-01

    In vitro neuronal networks of dissociated hippocampal or cortical tissues are one of the most attractive model systems for the physics and neuroscience communities. Cultured neurons grow and mature, develop axons and dendrites, and quickly connect to their neighbors to establish a spontaneously active network within a week. The resulting neuronal network is characterized by a combination of excitatory and inhibitory neurons coupled through synaptic connections that interact in a highly nonlinear manner. The nonlinear behavior emerges from the dynamics of both the neurons' spiking activity and synaptic transmission, together with biological noise. These ingredients give rise to a rich repertoire of phenomena that are still poorly understood, including the emergence and maintenance of periodic spontaneous activity, avalanches, propagation of fronts and synchronization. In this work we present an overview on the rich activity of cultured neuronal networks, and detail the minimal theoretical considerations needed to describe experimental observations.

  19. The capability approach: a guiding framework to improve population health and the attainment of the Sustainable Developmental Goals.

    PubMed

    Hirani, Shela Akbar Ali; Richter, Solina

    2017-02-21

    The world is progressing in terms of communication, innovative technology and cure of various diseases through advanced pharmacological preparations. Unfortunately, populations are still struggling with ill-health, disabilities, poverty, hunger, inequality, gender disparities and conflicts. Several questions come to mind in this regard: why are prosperity, health, peace and progress not evenly distributed and what is the best approach to address the issues associated with population health? The capability approach may offer a possible model. This approach is a blend of 5 key concepts: capabilities, functioning, agency, endowment, and conversion factors. It proposes an innovative approach to examine and enhance the quality of life and wellbeing of individuals. This reflective paper provides an overview of the capability approach, critically analyses population health from the theoretical lens of the capability approach and highlights the relevance of this approach to achieving the Sustainable Developmental Goals.

  20. Current State of Theoretical and Experimental Studies of the Voltage-Dependent Anion Channel (VDAC)

    PubMed Central

    Noskov, Sergei Yu.; Rostovtseva, Tatiana K.; Chamberlin, Adam C.; Teijido, Oscar; Jiang, Wei; Bezrukov, Sergey M.

    2016-01-01

    Voltage-dependent anion channel (VDAC), the major channel of the mitochondrial outer membrane provides a controlled pathway for respiratory metabolites in and out of the mitochondria. In spite of the wealth of experimental data from structural, biochemical, and biophysical investigations, the exact mechanisms governing selective ion and metabolite transport, especially the role of titratable charged residues and interactions with soluble cytosolic proteins, remain hotly debated in the field. The computational advances hold a promise to provide a much sought-after solution to many of the scientific disputes around solute and ion transport through VDAC and hence, across the mitochondrial outer membrane. In this review, we examine how Molecular Dynamics, Free Energy, and Brownian Dynamics simulations of the large β-barrel channel, VDAC, advanced our understanding. We will provide a short overview of non-conventional techniques and also discuss examples of how the modeling excursions into VDAC biophysics prospectively aid experimental efforts. PMID:26940625

  1. Cultural experiences of immigrant nurses at two hospitals in Chile.

    PubMed

    Rodríguez, Gabriel; Angélica-Muñoz, Luz; Hoga, Luiza Akiko Komura

    2014-01-01

    to explore the cultural experiences of nurses who immigrated to Chile. The study's theoretical framework was the Purnell Model for Cultural Competence. Leininger's Observation-Participation-Reflection method was developed at two hospitals in the city of Santiago, and ethnographic interviews were held with 15 immigrant nurses. among Purnell's 12 domains, the following were identified: Overview/heritage, Communication, Workforce issues, Family roles and organization, Biocultural ecology and Health-care practices. The difficulties were related to the language and its semantic meaning, the new responsibilities and the difficult relationship with colleagues. "In search of better horizons - the decision to immigrate", "Gaining confidence and establishing a support network - employability and professional performance" and "Seeking for people's acceptance - professional adaptation in a new cultural scenario" are cultural themes that represent their experiences. the competence to offer cultural care demands the development of public policies and continuing education programs at health institutions, specifically focused on immigrant nurses.

  2. A Low Nuclear Recoil Energy Threshold for Dark Matter Search with CRESST-III Detectors

    NASA Astrophysics Data System (ADS)

    Mancuso, M.; Angloher, G.; Bauer, P.; Bento, A.; Bucci, C.; Canonica, L.; D'Addabbo, A.; Defay, X.; Erb, A.; von Feilitzsch, Franz; Ferreiro Iachellini, N.; Gorla, P.; Gütlein, A.; Hauff, D.; Jochum, J.; Kiefer, M.; Kluck, H.; Kraus, H.; Lanfranchi, J. C.; Langenkämper, A.; Loebell, J.; Mondragon, E.; Münster, A.; Pagliarone, C.; Petricca, F.; Potzel, W.; Pröbst, F.; Puig, R.; Reindl, F.; Rothe, J.; Schäffner, K.; Schieck, J.; Schipperges, V.; Schönert, S.; Seidel, W.; Stahlberg, M.; Stodolsky, L.; Strandhagen, C.; Strauss, R.; Tanzke, A.; Thi, H. H. Trinh; Türkoglu, C.; Uffinger, M.; Ulrich, A.; Usherov, I.; Wawoczny, S.; Willers, M.; Wüstrich, M.

    2018-05-01

    The CRESST-III experiment (Cryogenic Rare Events Search with Superconducting Thermometers), located at the underground facility Laboratori Nazionali del Gran Sasso in Italy, uses scintillating CaWO_4 crystals as cryogenic calorimeters to search for direct dark matter interactions in detectors. A large part of the parameter space for spin-independent scattering off nuclei remains untested for dark matter particles with masses below a few GeV/c^2 , despite many naturally motivated theoretical models for light dark matter particles. The CRESST-III detectors are designed to achieve the performance required to probe the low-mass region of the parameter space with a sensitivity never reached before. In this paper, new results on the performance and an overview of the CRESST-III detectors will be presented, emphasizing the results about the low-energy threshold for nuclear recoil of CRESST-III Phase 1 which started collecting data in August 2016.

  3. Molecular Momentum Transport at Fluid-Solid Interfaces in MEMS/NEMS: A Review

    PubMed Central

    Cao, Bing-Yang; Sun, Jun; Chen, Min; Guo, Zeng-Yuan

    2009-01-01

    This review is focused on molecular momentum transport at fluid-solid interfaces mainly related to microfluidics and nanofluidics in micro-/nano-electro-mechanical systems (MEMS/NEMS). This broad subject covers molecular dynamics behaviors, boundary conditions, molecular momentum accommodations, theoretical and phenomenological models in terms of gas-solid and liquid-solid interfaces affected by various physical factors, such as fluid and solid species, surface roughness, surface patterns, wettability, temperature, pressure, fluid viscosity and polarity. This review offers an overview of the major achievements, including experiments, theories and molecular dynamics simulations, in the field with particular emphasis on the effects on microfluidics and nanofluidics in nanoscience and nanotechnology. In Section 1 we present a brief introduction on the backgrounds, history and concepts. Sections 2 and 3 are focused on molecular momentum transport at gas-solid and liquid-solid interfaces, respectively. Summary and conclusions are finally presented in Section 4. PMID:20087458

  4. Dispersal

    USGS Publications Warehouse

    Clobert, J.; Danchin, E.; Dhondt, A.A.; Nichols, J.D.

    2001-01-01

    The ability of species to migrate and disperse is a trait that has interested ecologists for many years. Now that so many species and ecosystems face major environmental threats from habitat fragmentation and global climate change, the ability of species to adapt to these changes by dispersing, migrating, or moving between patches of habitat can be crucial to ensuring their survival. This book provides a timely and wide-ranging overview of the study of dispersal and incorporates much of the latest research. The causes, mechanisms, and consequences of dispersal at the individual, population, species and community levels are considered. The potential of new techniques and models for studying dispersal, drawn from molecular biology and demography, is also explored. Perspectives and insights are offered from the fields of evolution, conservation biology and genetics. Throughout the book, theoretical approaches are combined with empirical data, and care has been taken to include examples from as wide a range of species as possible.

  5. [Home childbirth: progress or retrocession?].

    PubMed

    de Sanfelice, Clara Fróes Oliveira; Shimo, Antonieta Keiko Kakuda

    2014-03-01

    Giving birth at home represents a rising modality of delivery care in the Brazilian society, although in unrepresentative proportion when compared to the number of hospital childbirths. In Brazil, the topic has been broadly discussed by different professional categories, highlighting the safety issue involved in the process. The aim of this theoretical and reflective study was to present a brief overview of the overall care related to home childbirth, also questioning the reality of the contemporary Brazilian obstetric scenario. The scientific literature presents both obstetric and neonatal outcomes as favorable to home childbirth; similar risks when compared to hospital childbirth and higher rates of maternal satisfaction, and these both factors justify its practice. Therefore, a movement of women who are deeply unhappy with the current model of obstetric care is currently observed and they have been opting for home childbirth as a response to institutional violence,fragmentation and depersonalization of hospital care.

  6. A review of conduction aphasia.

    PubMed

    Ardila, Alfredo

    2010-11-01

    In this paper, a historical overview of the interpretation of conduction aphasia is initially presented. It is emphasized that the name conduction aphasia was proposed by Wernicke and was interpreted as a disconnection between the temporal and frontal brain language areas; this interpretation was re-taken by Geschwind, attributing the arcuate fasciculus the main role in speech repetition disturbances and resulting in the so-called Wernicke-Geschwind model of language. With the introduction of contemporary neuroimaging techniques, this interpretation of conduction aphasia as a disconnection syndrome due to an impairment of the arcuate fasciculus has been challenged. It has been disclosed that the arcuate fasciculus does not really connect Wernicke's and Broca's areas, but Wernicke's and motor/premotor frontal areas. Furthermore, conduction aphasia can be found in cases of cortical damage without subcortical extension. It is concluded that conduction aphasia remains a controversial topic not only from the theoretic point of view, but also from the understanding of its neurologic foundations.

  7. The impact of seasonal rice price changes on rice self-consumption in farm household of rural Java

    NASA Astrophysics Data System (ADS)

    Ani, S. W.; Antriyandarti, E.

    2018-03-01

    Seasonal rice price changes are very volatile and not predictable. This price changes have a heterogeneous impact on public consumption. The problem of seasonal rice price changes is not only experienced by consumers, but also in the farmers side as producers. The objective of this study is to provide a detail overview and description of the changing seasonal rice self-consumption of farm households in rural Java in response to seasonal rice price changes and income shocks to anticipate seasonal scarcity. This paper constructs a theoretical model to address such seasonality of food deprivation by using one year of seasonally farm household panel data, empirically tests the extent to which farmers in rural Java can smooth their rice self-consumption from season to season in response to income shocks. The result shows that rice farmers increase their rice self-consumption when prices are high.

  8. Studying Dark Energy, Black Holes and Cosmic Feedback at X-ray Wavelengths: NASA's Constellation-X Mission

    NASA Technical Reports Server (NTRS)

    Hornschemeier, A.

    2005-01-01

    Among the most important topics in modern astrophysics are the nature of the dark energy equation of state, the formation and evolution of supermassive black holes in concert with galaxy bulges, and the self-regulating symmetry imposed by both stellar and AGN feedback. All of these topics are readily addressed with observations at X-ray wavelengths. For instance, theoretical models predict that the majority (98%) of the energy and metal content in starburst superwinds exists in the hot million-degree gas. The Constellation-X observatory is being developed to perform spatially resolved high-resolution X-ray spectroscopy so that we may directly measure the absolute element abundances and velocities of this hot gas. This talk focuses on the driving science behind this mission, which is one of two flagship missions in NASA's Beyond Einstein program. A general overview of the observatory's capabilities and basic technology will also be given.

  9. Foundations and Emerging Paradigms for Computing in Living Cells.

    PubMed

    Ma, Kevin C; Perli, Samuel D; Lu, Timothy K

    2016-02-27

    Genetic circuits, composed of complex networks of interacting molecular machines, enable living systems to sense their dynamic environments, perform computation on the inputs, and formulate appropriate outputs. By rewiring and expanding these circuits with novel parts and modules, synthetic biologists have adapted living systems into vibrant substrates for engineering. Diverse paradigms have emerged for designing, modeling, constructing, and characterizing such artificial genetic systems. In this paper, we first provide an overview of recent advances in the development of genetic parts and highlight key engineering approaches. We then review the assembly of these parts into synthetic circuits from the perspectives of digital and analog logic, systems biology, and metabolic engineering, three areas of particular theoretical and practical interest. Finally, we discuss notable challenges that the field of synthetic biology still faces in achieving reliable and predictable forward-engineering of artificial biological circuits. Copyright © 2016. Published by Elsevier Ltd.

  10. Normal mode analysis and applications in biological physics.

    PubMed

    Dykeman, Eric C; Sankey, Otto F

    2010-10-27

    Normal mode analysis has become a popular and often used theoretical tool in the study of functional motions in enzymes, viruses, and large protein assemblies. The use of normal modes in the study of these motions is often extremely fruitful since many of the functional motions of large proteins can be described using just a few normal modes which are intimately related to the overall structure of the protein. In this review, we present a broad overview of several popular methods used in the study of normal modes in biological physics including continuum elastic theory, the elastic network model, and a new all-atom method, recently developed, which is capable of computing a subset of the low frequency vibrational modes exactly. After a review of the various methods, we present several examples of applications of normal modes in the study of functional motions, with an emphasis on viral capsids.

  11. Review of electronic transport models for thermoelectric materials

    NASA Astrophysics Data System (ADS)

    Bulusu, A.; Walker, D. G.

    2008-07-01

    Thermoelectric devices have gained importance in recent years as viable solutions for applications such as spot cooling of electronic components, remote power generation in space stations and satellites etc. These solid-state devices have long been known for their reliability rather than their efficiency; they contain no moving parts, and their performance relies primarily on material selection, which has not generated many excellent candidates. Research in recent years has been focused on developing both thermoelectric structures and materials that have high efficiency. In general, thermoelectric research is two-pronged with (1) experiments focused on finding new materials and structures with enhanced thermoelectric performance and (2) analytical models that predict thermoelectric behavior to enable better design and optimization of materials and structures. While numerous reviews have discussed the importance of and dependence on materials for thermoelectric performance, an overview of how to predict the performance of various materials and structures based on fundamental quantities is lacking. In this paper we present a review of the theoretical models that were developed since thermoelectricity was first observed in 1821 by Seebeck and how these models have guided experimental material search for improved thermoelectric devices. A new quantum model is also presented, which provides opportunities for the optimization of nanoscale materials to enhance thermoelectric performance.

  12. Beller Lectureship: Materials for Li & Na Batteries :A Computational Materials Science Point of View

    NASA Astrophysics Data System (ADS)

    Ahuja, Rajeev

    Energy storage has been a theme for scientists for two hundred years. The Lead acid battery research on batteries occupied some of the best minds of 19th century. Plante in 1859 invented lead acid battery which starts your car and ignites internal combustion which takes over the propulsion. Although the lead battery is over 150 years old but the origin of its open circuit voltage (OCV) of 2.1 V is still known. In present talk, I will show how one can explain the origin of OCV of 2.1 V based on foundations of relativistic quantum mechanics. Surprisingly, seems to be the first time its chemistry has been theoretically modeled from the first principles. The main message of this work is that most of the electro-motoric force of the common lead battery comes from relativistic effects. In second part, I will provide an overview of the most recent theoretical studies undertaken by us in the field of materials for Li & Na ion batteries. For selected examples, I will show how ab initio calculations can be of use in the effort to reach a better understanding of battery materials and to occasionally also guide the search for new promising materials.

  13. Autobiographical memory decline in Alzheimer’s disease, a theoretical and clinical overview

    PubMed Central

    El Haj, Mohamad; Antoine, Pascal; Nandrino, Jean Louis; Kapogiannis, Dimitrios

    2017-01-01

    Autobiographical memory, or memory for personal experiences, allows individuals to define themselves and construct a meaningful life story. Decline of this ability, as observed in Alzheimer’s disease (AD), results in an impaired sense of self and identity. In our model (AMAD: Autobiographical Memory in Alzheimer’s Disease), we present a critical review of theories and findings regarding cognitive and neuroanatomical underpinnings of autobiographical memory and its decline in AD and highlight studies on its clinical rehabilitation. We propose that autobiographical recall in AD is mainly characterized by loss of associated episodic information, which leads to de-contextualization of autobiographical memories and a shift from reliving past events to a general sense of familiarity. This decline refers to retrograde, but also anterograde amnesia that affects newly acquired memories besides remote ones. One consequence of autobiographical memory decline in AD is decreased access to memories that shape self-consciousness, self-knowledge, and self-images, leading to a diminished sense of self and identity. The link between autobiographical decline and compromised sense of self in AD can also manifest itself as low correspondence and coherence between past memories and current goals and beliefs. By linking cognitive, neuroanatomical, and clinical aspects of autobiographical decline in AD, our review provides a theoretical foundation, which may lead to better rehabilitation strategies. PMID:26169474

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

    Bang, Yunkyu; Stewart, G. R.

    Although the pairing mechanism of Fe-based superconductors (FeSCs) has not yet been settled with consensus with regard to the pairing symmetry and the superconducting (SC) gap function, the vast majority of experiments support the existence of spin-singlet signchanging s-wave SC gaps on multi-bands (s±-wave state). This multi-band s±-wave state is a very unique gap state per se and displays numerous unexpected novel SC properties, such as a strong reduction of the coherence peak, non-trivial impurity effects, nodal-gap-like nuclear magnetic resonance signals, various Volovik effects in the specific heat (SH) and thermal conductivity, and anomalous scaling behaviors with a SH jumpmore » and condensation energy versus Tc, etc. In particular, many of these non-trivial SC properties can easily be mistaken as evidence for a nodal-gap state such as a d-wave gap. In this review, we provide detailed explanations of the theoretical principles for the various non-trivial SC properties of the s±-wave pairing state, and then critically compare the theoretical predictions with experiments on FeSCs. This will provide a pedagogical overview of to what extent we can coherently understand the wide range of different experiments on FeSCs within the s±-wave gap model.« less

  15. Superconducting properties of the s ± -wave state: Fe-based superconductors

    DOE PAGES

    Bang, Yunkyu; Stewart, G. R.

    2017-02-13

    Although the pairing mechanism of Fe-based superconductors (FeSCs) has not yet been settled with consensus with regard to the pairing symmetry and the superconducting (SC) gap function, the vast majority of experiments support the existence of spin-singlet signchanging s-wave SC gaps on multi-bands (s±-wave state). This multi-band s±-wave state is a very unique gap state per se and displays numerous unexpected novel SC properties, such as a strong reduction of the coherence peak, non-trivial impurity effects, nodal-gap-like nuclear magnetic resonance signals, various Volovik effects in the specific heat (SH) and thermal conductivity, and anomalous scaling behaviors with a SH jumpmore » and condensation energy versus Tc, etc. In particular, many of these non-trivial SC properties can easily be mistaken as evidence for a nodal-gap state such as a d-wave gap. In this review, we provide detailed explanations of the theoretical principles for the various non-trivial SC properties of the s±-wave pairing state, and then critically compare the theoretical predictions with experiments on FeSCs. This will provide a pedagogical overview of to what extent we can coherently understand the wide range of different experiments on FeSCs within the s±-wave gap model.« less

  16. From Bricks and Mortar to the Public Sphere in Cyberspace: Creating a Culture of Caring on the Digital Global Commons

    ERIC Educational Resources Information Center

    Delacruz, Elizabeth M.

    2009-01-01

    This paper is intended as a broad, conceptual and theoretical treatise on the aims of teaching art in the age of global digital media. To contextualize a set of general recommendations for art education technology pedagogy, I first provide an overview of the meteoric rise of on-line social networks, and consider questions about the nature and…

  17. Liquid fuel cells.

    PubMed

    Soloveichik, Grigorii L

    2014-01-01

    The advantages of liquid fuel cells (LFCs) over conventional hydrogen-oxygen fuel cells include a higher theoretical energy density and efficiency, a more convenient handling of the streams, and enhanced safety. This review focuses on the use of different types of organic fuels as an anode material for LFCs. An overview of the current state of the art and recent trends in the development of LFC and the challenges of their practical implementation are presented.

  18. National Study of Social Welfare and Rehabilitation Workers, Work, and Organizational Contexts. Research Report No. 1: Overview Study of the Dynamics of Worker Job Mobility.

    ERIC Educational Resources Information Center

    Social and Rehabilitation Service (DHEW), Washington, DC.

    The goals of this study were to review what is known about worker job mobility in the social welfare and rehabilitation services fields, to organize this knowledge, and to suggest improvements in career design and employee management in these fields. To supplement the review of research and theoretical literature, two sets of personal interviews…

  19. How the Theory of Computing Can Help in Space Exploration

    NASA Technical Reports Server (NTRS)

    Kreinovich, Vladik; Longpre, Luc

    1997-01-01

    The opening of the NASA Pan American Center for Environmental and Earth Sciences (PACES) at the University of Texas at El Paso made it possible to organize the student Center for Theoretical Research and its Applications in Computer Science (TRACS). In this abstract, we briefly describe the main NASA-related research directions of the TRACS center, and give an overview of the preliminary results of student research.

  20. Global Education or How to Most Effectively Implement Cross-Disciplinary Themes in the Curriculum of Primary School--Czechia's Example

    ERIC Educational Resources Information Center

    Karvánková, Petra; Popjaková, Dagmar; Kováríková, Vlasta

    2015-01-01

    The article gives an overview of the educational concept of global education at elementary schools in the Czech Republic. It analyses the theoretical basis and methodology of this concept. It reflects upon the literature concerning global education. Based on this it defines what the global dimension is. It gives a view of the development of…

  1. Is it necessary to discuss person-oriented research in community psychology?

    PubMed

    Anne Bogat, G

    2009-03-01

    A brief overview of the person orientation is provided. It is then argued that research in community psychology, similar to every other field in psychology, has mainly focused on variables, not individuals. Suggestions are provided for how the person orientation can be applied to understanding settings and environments as well as the theoretical and methodological contributions community psychologists can make to further person oriented methods.

  2. Motivation in Second Language Learning: A Historical Overview and Its Relevance in a Public High School in Pasto, Colombia

    ERIC Educational Resources Information Center

    Guerrero, Mario

    2015-01-01

    Motivation has a significant role in the process of language learning. It is important to understand its theoretical evolution in this field to be able to consider its relevance in the learning and teaching of a foreign language. Motivation is a term that is commonly used among language teachers and language learners but perhaps many are not aware…

  3. Testing charged current quasi-elastic and multinucleon interaction models in the NEUT neutrino interaction generator with published datasets from the MiniBooNE and MINERνA experiments

    NASA Astrophysics Data System (ADS)

    Wilkinson, C.; Terri, R.; Andreopoulos, C.; Bercellie, A.; Bronner, C.; Cartwright, S.; de Perio, P.; Dobson, J.; Duffy, K.; Furmanski, A. P.; Haegel, L.; Hayato, Y.; Kaboth, A.; Mahn, K.; McFarland, K. S.; Nowak, J.; Redij, A.; Rodrigues, P.; Sánchez, F.; Schwehr, J. D.; Sinclair, P.; Sobczyk, J. T.; Stamoulis, P.; Stowell, P.; Tacik, R.; Thompson, L.; Tobayama, S.; Wascko, M. O.; Żmuda, J.

    2016-04-01

    There has been a great deal of theoretical work on sophisticated charged current quasi-elastic (CCQE) neutrino interaction models in recent years, prompted by a number of experimental results that measured unexpectedly large CCQE cross sections on nuclear targets. As the dominant interaction mode at T2K energies, and the signal process in oscillation analyses, it is important for the T2K experiment to include realistic CCQE cross section uncertainties in T2K analyses. To this end, T2K's Neutrino Interaction Working Group has implemented a number of recent models in NEUT, T2K's primary neutrino interaction event generator. In this paper, we give an overview of the models implemented and present fits to published νμ and ν¯ μ CCQE cross section measurements from the MiniBooNE and MINER ν A experiments. The results of the fits are used to select a default cross section model for future T2K analyses and to constrain the cross section uncertainties of the model. We find strong tension between datasets for all models investigated. Among the evaluated models, the combination of a modified relativistic Fermi gas with multinucleon CCQE-like interactions gives the most consistent description of the available data.

  4. A historical overview of nuclear structure studies in Strasbourg Laboratories: instrumentation, measurements and theory modelling—hand-in-hand

    NASA Astrophysics Data System (ADS)

    Beck, F. A.

    2018-05-01

    This article overviews a long period of an important evolution in the nuclear structure research in Strasbourg Laboratories, focussed on tracking of the weaker and weaker experimental signals carrying the more and more important physics messages. In particular we address the research of signatures of the collective behaviour of the nucleus as suggested in the early works of Bohr, Mottelson and Rainwater—at high and very high angular momenta—as well as the competition between the collective and non-collective excitation modes. These ambitious goals were possible to achieve only by constructing powerful spectrometers and developing related detectors, electronics and data acquisition systems. The theoretical modelling developed in parallel, provided essential guidance when choosing the right experiments and optimising their realisation. Theory calculations were equally helpful in interpreting the results of experiments leading to a more complete understanding of the underlying physics. Moreover, thanks to the development of heavy ion accelerators, the Strasbourg centre was the place where crossed the ways of many experimenters from European countries both from the Western and from the Central part of Europe, the place of the gradual development of more and more sophisticated European gamma-spectrometers in collaboration with more and more laboratories from the increasing number of countries allowing for the frontier-level studies of the nuclear behaviour at very high angular momenta.

  5. An Overview of NASA's Oribital Debris Environment Model

    NASA Technical Reports Server (NTRS)

    Matney, Mark

    2010-01-01

    Using updated measurement data, analysis tools, and modeling techniques; the NASA Orbital Debris Program Office has created a new Orbital Debris Environment Model. This model extends the coverage of orbital debris flux throughout the Earth orbit environment, and includes information on the mass density of the debris as well as the uncertainties in the model environment. This paper will give an overview of this model and its implications for spacecraft risk analysis.

  6. PREFACE: 3rd Workshop on Theory, Modelling and Computational Methods for Semiconductors (TMCSIII)

    NASA Astrophysics Data System (ADS)

    Califano, Marco; Migliorato, Max; Probert, Matt

    2012-05-01

    These conference proceedings contain the written papers of the contributions presented at the 3rd International Conference on Theory, Modelling and Computational Methods for Semiconductor materials and nanostructures. The conference was held at the School of Electronic and Electrical Engineering, University of Leeds, Leeds, UK on 18-20 January 2012. The previous conferences in this series took place in 2010 at St William's College, York and in 2008 at the University of Manchester, UK. The development of high-speed computer architectures is finally allowing the routine use of accurate methods for calculating the structural, thermodynamic, vibrational, optical and electronic properties of semiconductors and their hetero- and nano-structures. The scope of this conference embraces modelling, theory and the use of sophisticated computational tools in semiconductor science and technology, where there is substantial potential for time-saving in R&D. Theoretical approaches represented in this meeting included: Density Functional Theory, Tight Binding, Semiempirical Pseudopotential Methods, Effective Mass Models, Empirical Potential Methods and Multiscale Approaches. Topics included, but were not limited to: Optical and Transport Properties of Quantum Nanostructures including Colloids and Nanotubes, Plasmonics, Magnetic Semiconductors, Graphene, Lasers, Photonic Structures, Photovoltaic and Electronic Devices. This workshop ran for three days, with the objective of bringing together UK and international leading experts in the theoretical modelling of Group IV, III-V and II-VI semiconductors, as well as students, postdocs and early-career researchers. The first day focused on providing an introduction and overview of this vast field, aimed particularly at students, with several lectures given by recognised experts in various theoretical approaches. The following two days showcased some of the best theoretical research carried out in the UK in this field, with several contributions also from representatives of renowned theoretical groups from many European countries (Spain, France, Ireland, Germany, Italy, Poland, Denmark, Sweden, Serbia, Greece, etc.), as well as Asia (India) and Africa (Algeria, Tunisia and South Africa). We would like to thank all participants for making this a very successful meeting and for their contribution to the conference programme and these proceedings. We would also like to acknowledge the financial support from the Institute of Physics (Computational Physics group and Semiconductor Physics group), and QuantumWise (distributors of Atomistix). The Editors Acknowledgments Conference Organising Committee: Marco Califano (University of Leeds) Max Migliorato (University of Manchester) Matt Probert (University of York) Programme Committee: Stewart Clark (University of Durham) Aldo Di Carlo (University of Rome 'Tor Vergata', Italy) Ben Hourahine (University of Strathclyde) Lev Kantorovich (King's College London) Risto Nieminen (Helsinki University of Technology, Finland) Eoin O'Reilly (Tyndall Institute Cork, Republic of Ireland) Mauro Pereira (Sheffield Hallam University) John Robertson (University of Cambridge) Mervin Roy (University of Leicester) Stanko Tomic (University of Salford) David Whittaker (University of Sheffield) The proceedings were edited and compiled by Marco Califano, Max Migliorato and Matt Probert.

  7. Peridynamics with LAMMPS : a user guide.

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

    Lehoucq, Richard B.; Silling, Stewart Andrew; Plimpton, Steven James

    2008-01-01

    Peridynamics is a nonlocal formulation of continuum mechanics. The discrete peridynamic model has the same computational structure as a molecular dynamic model. This document details the implementation of a discrete peridynamic model within the LAMMPS molecular dynamic code. This document provides a brief overview of the peridynamic model of a continuum, then discusses how the peridynamic model is discretized, and overviews the LAMMPS implementation. A nontrivial example problem is also included.

  8. Nitrogen dynamics in flooded soil systems: an overview on concepts and performance of models

    PubMed Central

    Nurulhuda, Khairudin; Gaydon, Donald S; Jing, Qi; Zakaria, Mohamad P; Struik, Paul C

    2017-01-01

    Abstract Extensive modelling studies on nitrogen (N) dynamics in flooded soil systems have been published. Consequently, many N dynamics models are available for users to select from. With the current research trend, inclined towards multidisciplinary research, and with substantial progress in understanding of N dynamics in flooded soil systems, the objective of this paper is to provide an overview of the modelling concepts and performance of 14 models developed to simulate N dynamics in flooded soil systems. This overview provides breadth of knowledge on the models, and, therefore, is valuable as a first step in the selection of an appropriate model for a specific application. © 2017 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. PMID:28940491

  9. Magnetars: the physics behind observations. A review

    NASA Astrophysics Data System (ADS)

    Turolla, R.; Zane, S.; Watts, A. L.

    2015-11-01

    Magnetars are the strongest magnets in the present universe and the combination of extreme magnetic field, gravity and density makes them unique laboratories to probe current physical theories (from quantum electrodynamics to general relativity) in the strong field limit. Magnetars are observed as peculiar, burst-active x-ray pulsars, the anomalous x-ray pulsars (AXPs) and the soft gamma repeaters (SGRs); the latter emitted also three ‘giant flares’, extremely powerful events during which luminosities can reach up to 1047erg s-1 for about one second. The last five years have witnessed an explosion in magnetar research which has led, among other things, to the discovery of transient, or ‘outbursting’, and ‘low-field’ magnetars. Substantial progress has been made also on the theoretical side. Quite detailed models for explaining the magnetars’ persistent x-ray emission, the properties of the bursts, the flux evolution in transient sources have been developed and confronted with observations. New insight on neutron star asteroseismology has been gained through improved models of magnetar oscillations. The long-debated issue of magnetic field decay in neutron stars has been addressed, and its importance recognized in relation to the evolution of magnetars and to the links among magnetars and other families of isolated neutron stars. The aim of this paper is to present a comprehensive overview in which the observational results are discussed in the light of the most up-to-date theoretical models and their implications. This addresses not only the particular case of magnetar sources, but the more fundamental issue of how physics in strong magnetic fields can be constrained by the observations of these unique sources.

  10. Mixed phase clouds: observations and theoretical advances (overview)

    NASA Astrophysics Data System (ADS)

    Korolev, Alexei

    2013-04-01

    Mixed phase clouds play important role in precipitation formation and radiation budget of the Earth. The microphysical measurements in mixed phase clouds are notoriously difficult due to many technical challenges. The airborne instrumentation for characterization of the microstructure of mixed phase clouds is discussed. The results multiyear airborne observations and measurements of frequency of occurrence of mixed phase, characteristic spatial scales, humidity in mixed phase and ice clouds are presented. A theoretical framework describing the thermodynamics and phase transformation of a three phase component system consisting of ice particles, liquid droplets and water vapor is discussed. It is shown that the Wegener-Bergeron-Findeisen process plays different role in clouds with different dynamics. The problem of maintenance and longevity of mixed phase clouds is discussed.

  11. The National Solar Radiation Database (NSRDB): A Brief Overview

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

    Habte, Aron M; Sengupta, Manajit; Lopez, Anthony

    This poster presents a high-level overview of the National Solar Radiation Database (NSRDB). The NSRDB uses the physics-based model (PSM), which was developed using: adapted PATMOS-X model for cloud identification and properties, REST-2 model for clear-sky conditions, and NREL's Fast All-sky Radiation Model for Solar Applications (FARMS) for cloudy-sky Global Horizontal Irradiance (GHI) solar irradiance calculations.

  12. Developments in the application of the geometrical theory of diffraction and computer graphics to aircraft inter-antenna coupling analysis

    NASA Astrophysics Data System (ADS)

    Bogusz, Michael

    1993-01-01

    The need for a systematic methodology for the analysis of aircraft electromagnetic compatibility (EMC) problems is examined. The available computer aids used in aircraft EMC analysis are assessed and a theoretical basis is established for the complex algorithms which identify and quantify electromagnetic interactions. An overview is presented of one particularly well established aircraft antenna to antenna EMC analysis code, the Aircraft Inter-Antenna Propagation with Graphics (AAPG) Version 07 software. The specific new algorithms created to compute cone geodesics and their associated path losses and to graph the physical coupling path are discussed. These algorithms are validated against basic principles. Loss computations apply the uniform geometrical theory of diffraction and are subsequently compared to measurement data. The increased modelling and analysis capabilities of the newly developed AAPG Version 09 are compared to those of Version 07. Several models of real aircraft, namely the Electronic Systems Trainer Challenger, are generated and provided as a basis for this preliminary comparative assessment. Issues such as software reliability, algorithm stability, and quality of hardcopy output are also discussed.

  13. The neural control of singing

    PubMed Central

    Zarate, Jean Mary

    2013-01-01

    Singing provides a unique opportunity to examine music performance—the musical instrument is contained wholly within the body, thus eliminating the need for creating artificial instruments or tasks in neuroimaging experiments. Here, more than two decades of voice and singing research will be reviewed to give an overview of the sensory-motor control of the singing voice, starting from the vocal tract and leading up to the brain regions involved in singing. Additionally, to demonstrate how sensory feedback is integrated with vocal motor control, recent functional magnetic resonance imaging (fMRI) research on somatosensory and auditory feedback processing during singing will be presented. The relationship between the brain and singing behavior will be explored also by examining: (1) neuroplasticity as a function of various lengths and types of training, (2) vocal amusia due to a compromised singing network, and (3) singing performance in individuals with congenital amusia. Finally, the auditory-motor control network for singing will be considered alongside dual-stream models of auditory processing in music and speech to refine both these theoretical models and the singing network itself. PMID:23761746

  14. Future Trends in Solar Radio Astronomy and Coronal Magnetic-Field Measurements

    NASA Astrophysics Data System (ADS)

    Fleishman, Gregory; Nita, Gelu; Gary, Dale

    Solar radio astronomy has an amazingly rich, but yet largely unexploited, potential for probing the solar corona and chromosphere. Radio emission offers multiple ways of detecting and tracking electron beams, studying chromospheric and coronal thermal structure, plasma processes, particle acceleration, and measuring magnetic fields. To turn the mentioned potential into real routine diagnostics, two major components are needed: (1) well-calibrated observations with high spatial, spectral, and temporal resolutions and (2) accurate and reliable theoretical models and fast numerical tools capable of recovering the emission source parameters from the radio data. This report gives a brief overview of the new, expanded, and planned radio facilities, such as Expanded Owens Valley Solar Array (EOVSA), Jansky Very Large Array (JVLA), Chinese Solar Radio Heliograph (CSRH), Upgraded Siberian Solar Radio Telescope (USSRT), and Frequency Agile Solar Radiotelescope (FASR) with the emphasis on their ability to measure the coronal magnetic fields in active regions and flares. In particular, we emphasize the new tools for 3D modeling of the radio emission and forward fitting tools in development needed to derive the magnetic field data from the radio measurements.

  15. Dynamic computer simulations of electrophoresis: three decades of active research.

    PubMed

    Thormann, Wolfgang; Caslavska, Jitka; Breadmore, Michael C; Mosher, Richard A

    2009-06-01

    Dynamic models for electrophoresis are based upon model equations derived from the transport concepts in solution together with user-inputted conditions. They are able to predict theoretically the movement of ions and are as such the most versatile tool to explore the fundamentals of electrokinetic separations. Since its inception three decades ago, the state of dynamic computer simulation software and its use has progressed significantly and Electrophoresis played a pivotal role in that endeavor as a large proportion of the fundamental and application papers were published in this periodical. Software is available that simulates all basic electrophoretic systems, including moving boundary electrophoresis, zone electrophoresis, ITP, IEF and EKC, and their combinations under almost exactly the same conditions used in the laboratory. This has been employed to show the detailed mechanisms of many of the fundamental phenomena that occur in electrophoretic separations. Dynamic electrophoretic simulations are relevant for separations on any scale and instrumental format, including free-fluid preparative, gel, capillary and chip electrophoresis. This review includes a historical overview, a survey of current simulators, simulation examples and a discussion of the applications and achievements of dynamic simulation.

  16. Cosmological tests of modified gravity.

    PubMed

    Koyama, Kazuya

    2016-04-01

    We review recent progress in the construction of modified gravity models as alternatives to dark energy as well as the development of cosmological tests of gravity. Einstein's theory of general relativity (GR) has been tested accurately within the local universe i.e. the Solar System, but this leaves the possibility open that it is not a good description of gravity at the largest scales in the Universe. This being said, the standard model of cosmology assumes GR on all scales. In 1998, astronomers made the surprising discovery that the expansion of the Universe is accelerating, not slowing down. This late-time acceleration of the Universe has become the most challenging problem in theoretical physics. Within the framework of GR, the acceleration would originate from an unknown dark energy. Alternatively, it could be that there is no dark energy and GR itself is in error on cosmological scales. In this review, we first give an overview of recent developments in modified gravity theories including f(R) gravity, braneworld gravity, Horndeski theory and massive/bigravity theory. We then focus on common properties these models share, such as screening mechanisms they use to evade the stringent Solar System tests. Once armed with a theoretical knowledge of modified gravity models, we move on to discuss how we can test modifications of gravity on cosmological scales. We present tests of gravity using linear cosmological perturbations and review the latest constraints on deviations from the standard [Formula: see text]CDM model. Since screening mechanisms leave distinct signatures in the non-linear structure formation, we also review novel astrophysical tests of gravity using clusters, dwarf galaxies and stars. The last decade has seen a number of new constraints placed on gravity from astrophysical to cosmological scales. Thanks to on-going and future surveys, cosmological tests of gravity will enjoy another, possibly even more, exciting ten years.

  17. Bayesian flood forecasting methods: A review

    NASA Astrophysics Data System (ADS)

    Han, Shasha; Coulibaly, Paulin

    2017-08-01

    Over the past few decades, floods have been seen as one of the most common and largely distributed natural disasters in the world. If floods could be accurately forecasted in advance, then their negative impacts could be greatly minimized. It is widely recognized that quantification and reduction of uncertainty associated with the hydrologic forecast is of great importance for flood estimation and rational decision making. Bayesian forecasting system (BFS) offers an ideal theoretic framework for uncertainty quantification that can be developed for probabilistic flood forecasting via any deterministic hydrologic model. It provides suitable theoretical structure, empirically validated models and reasonable analytic-numerical computation method, and can be developed into various Bayesian forecasting approaches. This paper presents a comprehensive review on Bayesian forecasting approaches applied in flood forecasting from 1999 till now. The review starts with an overview of fundamentals of BFS and recent advances in BFS, followed with BFS application in river stage forecasting and real-time flood forecasting, then move to a critical analysis by evaluating advantages and limitations of Bayesian forecasting methods and other predictive uncertainty assessment approaches in flood forecasting, and finally discusses the future research direction in Bayesian flood forecasting. Results show that the Bayesian flood forecasting approach is an effective and advanced way for flood estimation, it considers all sources of uncertainties and produces a predictive distribution of the river stage, river discharge or runoff, thus gives more accurate and reliable flood forecasts. Some emerging Bayesian forecasting methods (e.g. ensemble Bayesian forecasting system, Bayesian multi-model combination) were shown to overcome limitations of single model or fixed model weight and effectively reduce predictive uncertainty. In recent years, various Bayesian flood forecasting approaches have been developed and widely applied, but there is still room for improvements. Future research in the context of Bayesian flood forecasting should be on assimilation of various sources of newly available information and improvement of predictive performance assessment methods.

  18. Neutrino-nucleus cross sections for oscillation experiments

    NASA Astrophysics Data System (ADS)

    Katori, Teppei; Martini, Marco

    2018-01-01

    Neutrino oscillations physics is entering an era of high precision. In this context, accelerator-based neutrino experiments need a reduction in systematic errors to the level of a few percent. Today, one of the most important sources of systematic errors are neutrino-nucleus cross sections which, in the energy region of hundreds of MeV to a few GeV, are known to a precision not exceeding 20%. In this article we review the present experimental and theoretical knowledge of neutrino-nucleus interaction physics. After introducing neutrino-oscillation physics and accelerator-based neutrino experiments, we give an overview of general aspects of neutrino-nucleus cross sections, from both the theoretical and experimental point of view. Then, we focus on these cross sections in different reaction channels. We start with the quasi-elastic and quasi-elastic-like cross section, placing a special emphasis on the multinucleon emission channel, which has attracted a lot of attention in the last few years. We review the main aspects of the different microscopic models for this channel by discussing analogies and the differences among them. The discussion is always driven by a comparison with the experimental data. We then consider the one-pion production channel where agreement between data and theory remains highly unsatisfactory. We describe how to interpret pion data, and then analyze, in particular, the puzzle related to the difficulty of theoretical models and Monte Carlo to simultaneously describe MiniBooNE and MINERvA experimental results. Inclusive cross sections are also discussed, as well as the comparison between the {ν }μ and {ν }e cross sections, relevant for the charge-conjugation-parity violation experiments. The impact of nuclear effects on the reconstruction of neutrino energy and on the determination of the neutrino-oscillation parameters is also reviewed. Finally, we look to the future by discussing projects and efforts in relation to future detectors, beams, and analysis.

  19. Active control of large space structures: An introduction and overview

    NASA Technical Reports Server (NTRS)

    Doane, G. B., III; Tollison, D. K.; Waites, H. B.

    1985-01-01

    An overview of the large space structure (LSS) control system design problem is presented. The LSS is defined as a class of system, and LSS modeling techniques are discussed. Model truncation, control system objectives, current control law design techniques, and particular problem areas are discussed.

  20. Liquid fuel cells

    PubMed Central

    2014-01-01

    Summary The advantages of liquid fuel cells (LFCs) over conventional hydrogen–oxygen fuel cells include a higher theoretical energy density and efficiency, a more convenient handling of the streams, and enhanced safety. This review focuses on the use of different types of organic fuels as an anode material for LFCs. An overview of the current state of the art and recent trends in the development of LFC and the challenges of their practical implementation are presented. PMID:25247123

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