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Sample records for activity theory framework

  1. Activity Theory as a Framework For Designing Constructivist Learning Environments.

    ERIC Educational Resources Information Center

    Jonassen, David H.; Rohrer-Murphy, Lucia

    1999-01-01

    Defines activity theory as a socio-cultural and socio-historical lens through which the interaction of human activity and consciousness within its relevant environmental context can be analyzed. Describes how activity theory can be used as a framework for analyzing activities and settings for the purpose of designing constructivist learning…

  2. Modeling of Active Transmembrane Transport in a Mixture Theory Framework

    PubMed Central

    Ateshian, Gerard A.; Morrison, Barclay; Hung, Clark T.

    2010-01-01

    This study formulates governing equations for active transport across semi-permeable membranes within the framework of the theory of mixtures. In mixture theory, which models the interactions of any number of fluid and solid constituents, a supply term appears in the conservation of linear momentum to describe momentum exchanges among the constituents. In past applications, this momentum supply was used to model frictional interactions only, thereby describing passive transport processes. In this study, it is shown that active transport processes, which impart momentum to solutes or solvent, may also be incorporated in this term. By projecting the equation of conservation of linear momentum along the normal to the membrane, a jump condition is formulated for the mechano-electrochemical potential of fluid constituents which is generally applicable to nonequilibrium processes involving active transport. The resulting relations are simple and easy to use, and address an important need in the membrane transport literature. PMID:20213212

  3. A Conceptual Framework Based on Activity Theory for Mobile CSCL

    ERIC Educational Resources Information Center

    Zurita, Gustavo; Nussbaum, Miguel

    2007-01-01

    There is a need for collaborative group activities that promote student social interaction in the classroom. Handheld computers interconnected by a wireless network allow people who work on a common task to interact face to face while maintaining the mediation afforded by a technology-based system. Wirelessly interconnected handhelds open up new…

  4. Blogs and Social Network Sites as Activity Systems: Exploring Adult Informal Learning Process through Activity Theory Framework

    ERIC Educational Resources Information Center

    Heo, Gyeong Mi; Lee, Romee

    2013-01-01

    This paper uses an Activity Theory framework to explore adult user activities and informal learning processes as reflected in their blogs and social network sites (SNS). Using the assumption that a web-based space is an activity system in which learning occurs, typical features of the components were investigated and each activity system then…

  5. Activity Theory as a Conceptual Framework for Understanding Teacher Approaches to Information and Communication Technologies

    ERIC Educational Resources Information Center

    Karasavvidis, Ilias

    2009-01-01

    While the issue of teachers' perspectives on the barriers to technology use has received considerable attention, teacher concerns have not been studied in a systematic and holistic way. The present paper examines teacher concerns regarding a proposed technology-based innovation using Activity Theory as a theoretical framework. Fifty-one teachers…

  6. Activity Theory as a Framework for Designing the Model of College English Listening

    ERIC Educational Resources Information Center

    Zhang, Jianfeng

    2014-01-01

    Activity theory signifies that activities are at the centre of human behaviour and it has been used to study cognitive process in many fields. Nowadays, college English listening learning is time-consuming but less effective in China, so enhancing the performance of listening instruction is a very hot topic. Theoretically, activity theory is able…

  7. Pavlov's Position on Old Age within the Framework of the Theory of Higher Nervous Activity.

    ERIC Educational Resources Information Center

    Windholz, George

    1995-01-01

    In later life, I. P. Pavlov incorporated his findings on aging into his theory of higher nervous activity. Some of the major findings showed that salivary conditioning and stimulus differentiation were difficult to establish in old dogs, but that conditioned reflexes established earlier in life persisted into old age. Pavlov hypothesized that…

  8. Activity Theory as a Theoretical Framework for Health Self-Quantification: A Systematic Review of Empirical Studies

    PubMed Central

    2016-01-01

    Background Self-quantification (SQ) is a way of working in which, by using tracking tools, people aim to collect, manage, and reflect on personal health data to gain a better understanding of their own body, health behavior, and interaction with the world around them. However, health SQ lacks a formal framework for describing the self-quantifiers’ activities and their contextual components or constructs to pursue these health related goals. Establishing such framework is important because it is the first step to operationalize health SQ fully. This may in turn help to achieve the aims of health professionals and researchers who seek to make or study changes in the self-quantifiers’ health systematically. Objective The aim of this study was to review studies on health SQ in order to answer the following questions: What are the general features of the work and the particular activities that self-quantifiers perform to achieve their health objectives? What constructs of health SQ have been identified in the scientific literature? How have these studies described such constructs? How would it be possible to model these constructs theoretically to characterize the work of health SQ? Methods A systematic review of peer-reviewed literature was conducted. A total of 26 empirical studies were included. The content of these studies was thematically analyzed using Activity Theory as an organizing framework. Results The literature provided varying descriptions of health SQ as data-driven and objective-oriented work mediated by SQ tools. From the literature, we identified two types of SQ work: work on data (ie, data management activities) and work with data (ie, health management activities). Using Activity Theory, these activities could be characterized into 6 constructs: users, tracking tools, health objectives, division of work, community or group setting, and SQ plan and rules. We could not find a reference to any single study that accounted for all these activities and

  9. Pavlov's conceptualization of voluntary movements within the framework of the theory of higher nervous activity.

    PubMed

    Windholz, G

    1998-01-01

    Pavlov became interested in the nature of voluntary movements after receiving Konorski and Miller's letter in 1928 describing their experiments on conditioning of motor movements in dogs. Their paradigmatic experiment involved presenting an indifferent stimulus, followed by passive raising of the dog's leg and then reinforcement. If the same stimulus was provided during a number of trials, the animal lifted its corresponding leg. In 1928 Pavlov asked his students to condition motor movements in his laboratory. Although their findings were equivocal, Pavlov incorporated the so-called voluntary movements into his theory of higher nervous activity. Voluntary movements were responses to external environmental contingencies. On the cortical level, the motor analyzer's cells had both afferent and efferent functions. In Pavlov's view, the motor analyzer's cells established connections with the afferent cells of other sensory analyzers. Pavlov held that motor movements, as responses to external and internal environments, give humans the illusion of voluntary behavior. PMID:9805363

  10. The Systems Theory Framework of Career Development

    ERIC Educational Resources Information Center

    McMahon, Mary

    2011-01-01

    The Systems Theory Framework (STF; McMahon & Patton, 1995; Patton & McMahon, 2006) of career development was proposed as a metatheoretical framework that accommodates the contribution of all theories and offers an integrative and coherent framework of career influences. In this article, the author provides an overview of the STF, outlines its…

  11. Activity Theory as a Framework for Investigating District-Classroom System Interactions and Their Influences on Technology Integration

    ERIC Educational Resources Information Center

    Anthony, Anika Ball

    2012-01-01

    Technology implementation research indicates that teachers' beliefs and knowledge, as well as a host of institutional factors, can influence technology integration. Drawing on third-generation activity theory, this article conceptualizes technology implementation as a network of planning and integration activities carried out by technology…

  12. A Framework for Theory Analysis

    ERIC Educational Resources Information Center

    Duffey, Margery; Muhlenkamp, Ann F.

    1974-01-01

    The paper examines two theories in nursing--those of Peplau and Rogers. The works of these two theorists were selected because they illustrate variation in approach. The origin of the problems, the methods, the character of the subject matter, and the expected outcomes of testing are the four questions used in the analysis. (MW)

  13. Unicam Activity Framework (UAF)

    ERIC Educational Resources Information Center

    Gagliardi, R.; Mauri, M.; Polzonetti, A.

    2016-01-01

    This presentation illustrates the framework of processing performance of the faculty of the University of Camerino. The evaluation criteria are explained and the technological structure that allows automatic performance assessment available online anywhere and anytime. The designed framework is usually applied to the performance evaluation of…

  14. Activity Theory and Ontology

    ERIC Educational Resources Information Center

    Peim, Nick

    2009-01-01

    This paper seeks to re-examine Yrio Engestrom's activity theory as a technology of knowledge designed to enable positive transformations of specific practices. The paper focuses on a key paper where Engestrom defines the nature and present state of activity theory. Beginning with a brief account of the relations between activity theory and…

  15. Reflections on Activity Theory

    ERIC Educational Resources Information Center

    Bakhurst, David

    2009-01-01

    It is sometimes suggested that activity theory represents the most important legacy of Soviet philosophy and psychology. But what exactly "is" activity theory? The canonical account in the West is given by Engestrom, who identifies three stages in the theory's development: from Vygotsky's insights, through Leontiev's articulation of the…

  16. Connecting Relational Theory and the Systems Theory Framework: Individuals and Their Systems

    ERIC Educational Resources Information Center

    Patton, Wendy

    2007-01-01

    The Systems Theory Framework (STF) facilitates the inclusion of relevant aspects of multiple existing theories within an integrated framework, wherein relevance and meaning is decided upon by each individual. Patton and McMahon emphasise that the application of the Systems Theory Framework in integrating theory and practice is located within the…

  17. Relationships among Classical Test Theory and Item Response Theory Frameworks via Factor Analytic Models

    ERIC Educational Resources Information Center

    Kohli, Nidhi; Koran, Jennifer; Henn, Lisa

    2015-01-01

    There are well-defined theoretical differences between the classical test theory (CTT) and item response theory (IRT) frameworks. It is understood that in the CTT framework, person and item statistics are test- and sample-dependent. This is not the perception with IRT. For this reason, the IRT framework is considered to be theoretically superior…

  18. A Framework for Chaos Theory Career Counselling

    ERIC Educational Resources Information Center

    Pryor, Robert G. L.

    2010-01-01

    Theory in career development counselling provides a map that counsellors can use to understand and structure the career counselling process. It also provides a means to communicate this understanding and structuring to their clients as part of the counselling intervention. The chaos theory of careers draws attention to the complexity,…

  19. Generalizing Prototype Theory: A Formal Quantum Framework.

    PubMed

    Aerts, Diederik; Broekaert, Jan; Gabora, Liane; Sozzo, Sandro

    2016-01-01

    Theories of natural language and concepts have been unable to model the flexibility, creativity, context-dependence, and emergence, exhibited by words, concepts and their combinations. The mathematical formalism of quantum theory has instead been successful in capturing these phenomena such as graded membership, situational meaning, composition of categories, and also more complex decision making situations, which cannot be modeled in traditional probabilistic approaches. We show how a formal quantum approach to concepts and their combinations can provide a powerful extension of prototype theory. We explain how prototypes can interfere in conceptual combinations as a consequence of their contextual interactions, and provide an illustration of this using an intuitive wave-like diagram. This quantum-conceptual approach gives new life to original prototype theory, without however making it a privileged concept theory, as we explain at the end of our paper. PMID:27065436

  20. Generalizing Prototype Theory: A Formal Quantum Framework

    PubMed Central

    Aerts, Diederik; Broekaert, Jan; Gabora, Liane; Sozzo, Sandro

    2016-01-01

    Theories of natural language and concepts have been unable to model the flexibility, creativity, context-dependence, and emergence, exhibited by words, concepts and their combinations. The mathematical formalism of quantum theory has instead been successful in capturing these phenomena such as graded membership, situational meaning, composition of categories, and also more complex decision making situations, which cannot be modeled in traditional probabilistic approaches. We show how a formal quantum approach to concepts and their combinations can provide a powerful extension of prototype theory. We explain how prototypes can interfere in conceptual combinations as a consequence of their contextual interactions, and provide an illustration of this using an intuitive wave-like diagram. This quantum-conceptual approach gives new life to original prototype theory, without however making it a privileged concept theory, as we explain at the end of our paper. PMID:27065436

  1. A Framework for Theory and Research on Adult Education Participation.

    ERIC Educational Resources Information Center

    Cookson, Peter S.

    1986-01-01

    Proposed is a comprehensive, multivariate, multirealm theoretical framework with which to integrate and advance the theory and research of adult education participation. This article describes elements of the framework that have already been investigated and those for which there are gaps in the literature. Suggestions for further research to…

  2. Transforming Teacher Education, An Activity Theory Analysis

    ERIC Educational Resources Information Center

    McNicholl, Jane; Blake, Allan

    2013-01-01

    This paper explores the work of teacher education in England and Scotland. It seeks to locate this work within conflicting sociocultural views of professional practice and academic work. Drawing on an activity theory framework that integrates the analysis of these seemingly contradictory discourses with a study of teacher educators' practical…

  3. Supporting Teachers on Science-Focused School Trips: Towards an Integrated Framework of Theory and Practice

    ERIC Educational Resources Information Center

    DeWitt, Jennifer; Osborne, Jonathan

    2007-01-01

    Although science centres and museums are important educational resources, school trips to these places are not often conducted in a manner that could maximise learning. In addressing this issue, a Framework for Museum Practice (FMP) is proposed, derived from the perspectives of Cultural Historical Activity Theory, theories of intrinsic motivation,…

  4. Weak Quantum Theory: Formal Framework and Selected Applications

    SciTech Connect

    Atmanspacher, Harald; Filk, Thomas; Roemer, Hartmann

    2006-01-04

    Two key concepts of quantum theory, complementarity and entanglement, are considered with respect to their significance in and beyond physics. An axiomatically formalized, weak version of quantum theory, more general than the ordinary quantum theory of physical systems, is described. Its mathematical structure generalizes the algebraic approach to ordinary quantum theory. The crucial formal feature leading to complementarity and entanglement is the non-commutativity of observables.The ordinary Hilbert space quantum mechanics can be recovered by stepwise adding the necessary features. This provides a hierarchy of formal frameworks of decreasing generality and increasing specificity. Two concrete applications, more specific than weak quantum theory and more general than ordinary quantum theory, are discussed: (i) complementarity and entanglement in classical dynamical systems, and (ii) complementarity and entanglement in the bistable perception of ambiguous stimuli.

  5. Conceptual Change from the Framework Theory Side of the Fence

    ERIC Educational Resources Information Center

    Vosniadou, Stella; Skopeliti, Irini

    2014-01-01

    We describe the main principles of the framework theory approach to conceptual change and briefly report on the results of a text comprehension study that investigated some of the hypotheses that derive from it. We claim that children construct a naive physics which is based on observation in the context of lay culture and which forms a relatively…

  6. Research on a Modified Framework of Implicit Personality Theories

    ERIC Educational Resources Information Center

    Ziegler, Albert; Stoeger, Heidrun

    2010-01-01

    There is ample evidence that labeled gifted students exhibit maladaptive behavior patterns. According to Carol Dweck those students who subscribe to a fixed view of their abilities are particularly at risk. In this contribution we extended Dweck's framework and distinguished two aspects of the implicit theory of one's own abilities. We…

  7. An Examination of Rater Drift within a Generalizability Theory Framework

    ERIC Educational Resources Information Center

    Harik, Polina; Clauser, Brian E.; Grabovsky, Irina; Nungester, Ronald J.; Swanson, Dave; Nandakumar, Ratna

    2009-01-01

    The present study examined the long-term usefulness of estimated parameters used to adjust the scores from a performance assessment to account for differences in rater stringency. Ratings from four components of the USMLE[R] Step 2 Clinical Skills Examination data were analyzed. A generalizability-theory framework was used to examine the extent to…

  8. Body parts in property theory: an integrated framework.

    PubMed

    Nwabueze, Remigius Nnamdi

    2014-01-01

    The role of property theory as a framework for analysis and regulation of body parts has become a debate of topical importance because of the emergence of biomedical technologies that utilise body parts, and also because the application of the concept of property, even with respect to historically and traditionally accepted forms of property, raises serious challenges to the property analyst. However, there is another reason for the topicality of property in relation to body parts: a proprietary approach confers on a claimant the advantage of continuing control that is tellingly lacking in non-property frameworks underpinned, for instance, by consent, negligence, privacy and unjust enrichment rules. In some circumstances, such as an unauthorised blood test performed on a blood sample obtained with consent, the continuing control provided by property law might be the only chance a claimant has to obtain a remedy. Economy of space, however, requires that only a prolegomenon on body parts and property theory is given below. Thus, the analysis begins by providing in outline a framework for comprehensive analysis of body parts within the realm of property theory; thereafter, the author engages with the normative question of whether body parts or rights exercisable over body parts could be admitted into the category of property. PMID:23371312

  9. Design Activity Framework for Visualization Design.

    PubMed

    McKenna, Sean; Mazur, Dominika; Agutter, James; Meyer, Miriah

    2014-12-01

    An important aspect in visualization design is the connection between what a designer does and the decisions the designer makes. Existing design process models, however, do not explicitly link back to models for visualization design decisions. We bridge this gap by introducing the design activity framework, a process model that explicitly connects to the nested model, a well-known visualization design decision model. The framework includes four overlapping activities that characterize the design process, with each activity explicating outcomes related to the nested model. Additionally, we describe and characterize a list of exemplar methods and how they overlap among these activities. The design activity framework is the result of reflective discussions from a collaboration on a visualization redesign project, the details of which we describe to ground the framework in a real-world design process. Lastly, from this redesign project we provide several research outcomes in the domain of cybersecurity, including an extended data abstraction and rich opportunities for future visualization research. PMID:26356933

  10. Abstract framework for the theory of statistical solutions

    NASA Astrophysics Data System (ADS)

    Bronzi, A. C.; Mondaini, C. F.; Rosa, R. M. S.

    2016-06-01

    An abstract framework for the theory of statistical solutions is developed for general evolution equations, extending the theory initially developed for the three-dimensional incompressible Navier-Stokes equations. The motivation for this concept is to model the evolution of uncertainties on the initial conditions for systems which have global solutions that are not known to be unique. Both concepts of statistical solution in trajectory space and in phase space are given, and the corresponding results of existence of statistical solution for the associated initial value problems are proved. The wide applicability of the theory is illustrated with the very incompressible Navier-Stokes equations, a reaction-diffusion equation, and a nonlinear wave equation, all displaying the property of global existence of weak solutions without a known result of global uniqueness.

  11. A Bayesian framework for active artificial perception.

    PubMed

    Ferreira, João Filipe; Lobo, Jorge; Bessière, Pierre; Castelo-Branco, Miguel; Dias, Jorge

    2013-04-01

    In this paper, we present a Bayesian framework for the active multimodal perception of 3-D structure and motion. The design of this framework finds its inspiration in the role of the dorsal perceptual pathway of the human brain. Its composing models build upon a common egocentric spatial configuration that is naturally fitting for the integration of readings from multiple sensors using a Bayesian approach. In the process, we will contribute with efficient and robust probabilistic solutions for cyclopean geometry-based stereovision and auditory perception based only on binaural cues, modeled using a consistent formalization that allows their hierarchical use as building blocks for the multimodal sensor fusion framework. We will explicitly or implicitly address the most important challenges of sensor fusion using this framework, for vision, audition, and vestibular sensing. Moreover, interaction and navigation require maximal awareness of spatial surroundings, which, in turn, is obtained through active attentional and behavioral exploration of the environment. The computational models described in this paper will support the construction of a simultaneously flexible and powerful robotic implementation of multimodal active perception to be used in real-world applications, such as human-machine interaction or mobile robot navigation. PMID:23014760

  12. An Application of Activity Theory

    ERIC Educational Resources Information Center

    Marken, James A.

    2006-01-01

    Activity Theory has often been used in workplace settings to gain new theoretical understandings about work and the humans who engage in work, but rarely has there been sufficient detail in the literature to allow HPT practitioners to do their own activity analysis. The detail presented in this case is sufficient for HPT practitioners to begin to…

  13. Conceptual Change from the Framework Theory Side of the Fence

    NASA Astrophysics Data System (ADS)

    Vosniadou, Stella; Skopeliti, Irini

    2014-07-01

    We describe the main principles of the framework theory approach to conceptual change and briefly report on the results of a text comprehension study that investigated some of the hypotheses that derive from it. We claim that children construct a naive physics which is based on observation in the context of lay culture and which forms a relatively coherent conceptual system—i.e., a framework theory—that can be used as a basis for explanation and prediction of everyday phenomena. Learning science requires fundamental ontological, epistemological, and representational changes in naive physics. These conceptual changes take a long time to be achieved, giving rise to fragmentation and synthetic conceptions. We also argue that both fragmentation and synthetic conceptions can be explained to result from learners' attempts assimilate scientific information into their existing but incompatible naive physics.

  14. Variation Theory: A Theory of Learning and a Useful Theoretical Framework for Chemical Education Research

    ERIC Educational Resources Information Center

    Bussey, Thomas J.; Orgill, MaryKay; Crippen, Kent J.

    2013-01-01

    Instructors are constantly baffled by the fact that two students who are sitting in the same class, who have access to the same materials, can come to understand a particular chemistry concept differently. Variation theory offers a theoretical framework from which to explore possible variations in experience and the resulting differences in…

  15. Technology, Mathematics and Activity Theory

    ERIC Educational Resources Information Center

    Lerman, Stephen

    2013-01-01

    This article describes 11 papers in which the authors report their research on technology as enhancement in the teaching and learning of mathematics, in the context of the application of activity theory for design and/or analysis. There is considerable diversity across the papers in how the authors have interpreted their task and in particular how…

  16. Concerning interpretations of activity theory.

    PubMed

    Mironenko, Irina A

    2013-09-01

    Activity theory (AT) is the most recognised part of Russian psychology outside Russia. However the general view of AT in international science is rather unilateral, lacking substantial aspects and areas necessary for proper understanding. This article is aimed at expanding the image of AT dominant in the mainstream which reduces the AT trend to A.N. Leontiev's theory. This reduction impoverishes the creative potentialities of the trend, and decreases the ability of AT to contribute to international science. We aim to reveal that AT is not limited to Leontiev's approach, to explain which ideas of the founders of AT, S.L. Rubinstein and L.S. Vygotsky, were pursued and which were rejected by A.N. Leontiev, and to assess another important contribution to the AT trend - the theory of B.G. Ananiev, where the ideas of AT's founders were developed which were not succeeded by A.N. Leontiev. Historical causes and consequences of the general reduction of the image of AT in the mainstream to Leontiev's theory are considered: why the discrepancies between views of Rubinstein, Vygotsky and Leontiev were hardly ever discussed in public and why other theories contemporary to Leontiev's theory were never given account appropriate to their value in Russia and remain almost unknown abroad. PMID:23512520

  17. Io. [theories concerning volcanic activity

    NASA Technical Reports Server (NTRS)

    Johnson, T. V.; Soderblom, L. A.

    1983-01-01

    A report on the continuing investigation of Io is presented. Gravitational resonance is discussed as the cause of Io's volcanism, and the volcanic activity is explained in terms of sulfur chemistry. Theories concerning the reasons for the two main types of volcanic eruptions on Io are advanced and correlated with geographical features of the satellite. The sulfur and silicate models of the calderas are presented, citing the strengths and weaknesses of each. Problems of the gravitational resonance theory of Io's heat source are then described. Finally, observations of Io planned for the Galileo mission are summarized.

  18. Reconstructing inflationary paradigm within Effective Field Theory framework

    NASA Astrophysics Data System (ADS)

    Choudhury, Sayantan

    2016-03-01

    In this paper my prime objective is to analyse the constraints on a sub-Planckian excursion of a single inflaton field within Effective Field Theory framework in a model independent fashion. For a generic single field inflationary potential, using the various parameterization of the primordial power spectrum I have derived the most general expression for the field excursion in terms of various inflationary observables, applying the observational constraints obtained from recent Planck 2015 and Planck 2015 + BICEP2/Keck Array data. By explicit computation I have reconstructed the structural form of the inflationary potential by constraining the Taylor expansion co-efficients appearing in the generic expansion of the potential within the Effective Field Theory. Next I have explicitly derived, a set of higher order inflationary consistency relationships, which would help us to break the degeneracy between various class of inflationary models by differentiating them. I also provided two simple examples of Effective Theory of inflation- inflection-point model and saddle-point model to check the compatibility of the prescribed methodology in the light of Planck 2015 and Planck 2015 + BICEP2/Keck Array data. Finally, I have also checked the validity of the prescription by estimating the cosmological parameters and fitting the theoretical CMB TT, TE and EE angular power spectra with the observed data within the multipole range 2 < l < 2500.

  19. Preventing information overload: cognitive load theory as an instructional framework for teaching pharmacology.

    PubMed

    Kaylor, Sara K

    2014-02-01

    Nursing students are challenged by content-laden curricula and learning environments that emphasize testing outcomes. Likewise, educators are challenged to support student-centered learning in a manner that encourages students to connect and act upon their personal motivations. This article describes the use of cognitive load theory (CLT) as an instructional design framework for an undergraduate pharmacology for nursing course. Guided by the principles of CLT, four instructional strategies were used in this course: (a) opening review activities, (b) providing students with lecture notes, (c) a "Top Five" prototype approach, and (d) deciphering "Need to Knows" from "Nice to Knows." Instructional style and strategies received positive student feedback and were found to promote a student-centered environment and active learning. On the basis of this feedback, cognitive load theory may be a successful and effective framework for undergraduate pharmacology and other nursing courses, thus assisting students and educators alike in overcoming obstacles imposed on learning environments. PMID:24444008

  20. PDAs as Lifelong Learning Tools: An Activity Theory Based Analysis

    ERIC Educational Resources Information Center

    Waycott, Jenny; Jones, Ann; Scanlon, Eileen

    2005-01-01

    This paper describes the use of an activity theory (AT) framework to analyze the ways that distance part time learners and mobile workers adapted and appropriated mobile devices for their activities and in turn how their use of these new tools changed the ways that they carried out their learning or their work. It is argued that there are two key…

  1. An Assessment of Agency Theory as a Framework for the Government-University Relationship

    ERIC Educational Resources Information Center

    Kivisto, Jussi

    2008-01-01

    The aim of this paper is to use agency theory as the theoretical framework for an examination of the government-university relationship and to assess the main strengths and weaknesses of the theory in this context. Because of its logically consistent framework, agency theory is able to manifest many of the complexities and difficulties that…

  2. Using Activity Theory to Model the Taiwan Atayal Students' Classroom Mathematical Activity

    ERIC Educational Resources Information Center

    Huang, Chih-Hsien; Lin, Fou-Lai

    2013-01-01

    From the sociocultural perspective, this research utilized activity theory as the theoretical framework to analyze the influences of cultural factors for Taiwanese Atayal junior high school students' study in mathematics. The research methodology adopted grounded theory, theoretical and methodological approaches which are illustrated through…

  3. Social theory and current affairs: a framework for intellectual engagement.

    PubMed

    Stones, Rob

    2014-06-01

    The paper aims to facilitate more adequate critical engagement with current affairs events by journalists, and with current affairs texts by audiences. It draws on social theory to provide the intellectual resources to enable this. The academic ambition is for the framework to be adopted and developed by social thinkers in producing exemplary critical readings of news and current affairs texts. To this end it is offered as a research paradigm. The paper situates its argument in relation to the wider literature in media and cultural studies, acknowledging the subtle skills required to appreciate the relative autonomy of texts. However, it draws attention to the lack of an adequate perspective with which to assess the frames, representations, and judgments within news and current affairs texts. To address this lacuna it proposes the conception of a social-theoretical frame, based on a number of meta-theoretical approaches, designed to provide audiences with a systematic means of addressing the status and adequacy of individual texts. Social theoretical frames can reveal the shortcomings of media framing of the contextual fields within which news and current affairs events take place. Two illustrative case studies are used to indicate the value and potential of the approach: the analysis of a short newspaper report of the return of protesters to Cairo's Tahrir Square in 2011, and a critique of four current affairs reports from various genres on the political turmoil in Thailand leading up to the clashes of May 2010. PMID:24766395

  4. Videogames, Tools for Change: A Study Based on Activity Theory

    ERIC Educational Resources Information Center

    Méndez, Laura; Lacasa, Pilar

    2015-01-01

    Introduction: The purpose of this study is to provide a framework for analysis from which to interpret the transformations that take place, as perceived by the participants, when commercial video games are used in the classroom. We will show how Activity Theory (AT) is able to explain and interpret these changes. Method: Case studies are…

  5. "Vygotsky's Neglected Legacy": Cultural-Historical Activity Theory

    ERIC Educational Resources Information Center

    Roth, Wolff-Michael; Lee, Yew-Jin

    2007-01-01

    The authors describe an evolving theoretical framework that has been called one of the best kept secrets of academia: cultural-historical activity theory, the result of proposals Lev Vygotsky first articulated but that his students and followers substantially developed to constitute much expanded forms in its second and third generations. Besides…

  6. Theory of active galactic nuclei

    NASA Technical Reports Server (NTRS)

    Shields, G. A.

    1986-01-01

    The involvement of accretion disks around supermassive black holes in the theory of active galactic nuclei (AGN) is discussed. The physics of thin and thick accretion disks is discussed and the partition between thermal and nonthermal energy production in supermassive disks is seen as uncertain. The thermal limit cycle may operate in supermassive disks (Shields, 1985), with accumulation of gas in the disk for periods of 10 to the 4th to 10 to the 7th years, punctuated by briefer outbursts during which the mass is rapidly transferred to smaller radii. An extended X-ray source in AGN is consistent with observations (Tennant and Mushotsky, 1983), and a large wind mass loss rate exceeding the central accretion rate means that only a fraction of the mass entering the disk will reach the central object; the rest being lost to the wind. Controversy in the relationship between the broad lines and the disk is also discussed.

  7. Hope Theory: A Framework for Understanding Suicidal Action

    ERIC Educational Resources Information Center

    Grewal, Parveen; Porter, James

    2007-01-01

    This article examines C. R. Snyder's (1994, 2000a) theory of hope and its application for understanding suicide. Strengths, weaknesses, and gaps in the suicide literature are outlined, and A. T. Beck's theory of hopelessness is compared with Snyder's hope theory. Hope theory constructs are used to examine the relationship of suicide to…

  8. Rethinking the Introduction of Particle Theory: A Substance-Based Framework

    ERIC Educational Resources Information Center

    Johnson, Philip; Papageorgiou, George

    2010-01-01

    In response to extensive research exposing students' poor understanding of the particle theory of matter, this article argues that the conceptual framework within which the theory is introduced could be a limiting factor. The standard school particle model is characterized as operating within a "solids, liquids, and gases" framework. Drawing on an…

  9. Time and Identity: A Framework for Research and Theory Formation

    ERIC Educational Resources Information Center

    Lichtwarck-Aschoff, Anna; van Geert, Paul; Bosma, Harke; Kunnen, Saskia

    2008-01-01

    This article presents a conceptual framework for the study of identity in the context of developmental and real-time. The framework consists of two dimensions related to the notion of time. One dimension involves the distinction between short- and long-term processes, or, as we call them, the micro- and macro-perspective on time. The second…

  10. Perturbative quantum field theory in the framework of the fermionic projector

    SciTech Connect

    Finster, Felix

    2014-04-15

    We give a microscopic derivation of perturbative quantum field theory, taking causal fermion systems and the framework of the fermionic projector as the starting point. The resulting quantum field theory agrees with standard quantum field theory on the tree level and reproduces all bosonic loop diagrams. The fermion loops are described in a different formalism in which no ultraviolet divergences occur.

  11. A Test for Theoretical Integration: Systems Theory Framework and Dialogical Self

    ERIC Educational Resources Information Center

    McIlveen, Peter

    2007-01-01

    The Systems Theory Framework (STF) is presented as an integrating and organising concept for the predominant theories of career. In order to test the integrative capacity of the STF, this research merges the STF's theoretical element of story with the Theory of Dialogical Self's model of personality. Implications for the practice of career…

  12. The Self-Care Deficit Nursing Theory as a curriculum conceptual framework in baccalaureate education.

    PubMed

    Berbiglia, Violeta A

    2011-04-01

    Although Dorothea Orem's Self-Care Deficit Nursing Theory has been used for curricula framework for years, it was not until 2001 that Orem identified the nursing practice sciences and the foundational nursing sciences and specified the appropriate content for the two sciences. The broad purpose of this paper is to reinforce the importance of utilizing nursing theories as curricular conceptual frameworks. The specific purpose is to delineate the appropriate content for baccalaureate programs that adopt a Self-Care Deficit Nursing Theory conceptual framework for their curriculum. PMID:21471038

  13. Root Metaphor Theory: A Philosophical Framework for Counseling and Psychotherapy.

    ERIC Educational Resources Information Center

    Lyddon, William J.

    1989-01-01

    Offers an overview of the root metaphors and philosophical assumptions associated with formism, mechanism, contextualism, and organicism, the four world views described in Pepper's 1942 philosophical treatise and his presentation of root metaphor theory. Examines recent and historical trends of development in counseling theory and practice within…

  14. Participatory Learning Theories: A Framework for Early Childhood Pedagogy

    ERIC Educational Resources Information Center

    Hedges, Helen; Cullen, Joy

    2012-01-01

    This paper continues scholarly conversations about appropriate theories of development to underpin early childhood pedagogy. It focuses on sociocultural theoretical perspectives and proposes that participatory learning theories (PLTs) underpin pedagogy built on principles specified in three curricular documents. Further, the paper argues that the…

  15. The Mapping of a Framework: Critical Race Theory and TESOL

    ERIC Educational Resources Information Center

    Liggett, Tonda

    2014-01-01

    In this article, I attempt to elucidate some key intersections between critical race theory (CRT) in synthesis with English language learning as a way to examine linguistic and racial identity in English language teaching. I ask: How does critical race theory apply to English language learners when language rather than race is fore-grounded? What…

  16. Integrating theory and practice. Conceptual frameworks of the CEFP.

    PubMed

    Preskill, H; Compton, D W; Baizerman, M; Smith, I E

    2001-01-01

    In this article, we describe how different conceptual frameworks contributed to the design, development, and implementation of the Collaborative Evaluation Fellows Project (CEFP). These frameworks are the following: utilization-focused evaluation (Patton, 1997); evaluative inquiry for learning in organizations (Preskill & Torres, 1999); and collaboration for a change (Himmelman, 1994). In addition, we explain how The Program Evaluation Standards (Joint Committee on Standards for Educational Evaluation, 1994) provided criteria for implementing and assessing the evaluation studies conducted through the CEFP. We conclude the article with examples of how the CEFP has changed the way American Cancer Society staff members and volunteers think about and conduct evaluations. PMID:11912849

  17. Family Systems Theory: A Unifying Framework for Codependence.

    ERIC Educational Resources Information Center

    Prest, Layne A.; Protinsky, Howard

    1993-01-01

    Considers addictions and construct of codependence. Offers critical review and synthesis of codependency literature, along with an intergenerational family systems framework for conceptualizing the relationship of the dysfunctional family to the construct of codependence. Presents theoretical basis for systemic clinical work and research in this…

  18. A Unified Framework for Monetary Theory and Policy Analysis.

    ERIC Educational Resources Information Center

    Lagos, Ricardo; Wright, Randall

    2005-01-01

    Search-theoretic models of monetary exchange are based on explicit descriptions of the frictions that make money essential. However, tractable versions of these models typically make strong assumptions that render them ill suited for monetary policy analysis. We propose a new framework, based on explicit micro foundations, within which macro…

  19. Using Cultural-Historical Activity Theory to Design and Evaluate an Educational Game in Science Education

    ERIC Educational Resources Information Center

    Lazarou, D.

    2011-01-01

    The aim of this paper is to describe a methodology for using Cultural-Historical Activity Theory (CHAT) at the initial stages of the design process of an educational game, by exploring how the theory can be used as a framework for producing not only usable but also useful computer tools. The research also aimed to investigate how the theory could…

  20. Connecting Practice, Theory and Method: Supporting Professional Doctoral Students in Developing Conceptual Frameworks

    ERIC Educational Resources Information Center

    Kumar, Swapna; Antonenko, Pavlo

    2014-01-01

    From an instrumental view, conceptual frameworks that are carefully assembled from existing literature in Educational Technology and related disciplines can help students structure all aspects of inquiry. In this article we detail how the development of a conceptual framework that connects theory, practice and method is scaffolded and facilitated…

  1. Using activity theory to study cultural complexity in medical education.

    PubMed

    Frambach, Janneke M; Driessen, Erik W; van der Vleuten, Cees P M

    2014-06-01

    There is a growing need for research on culture, cultural differences and cultural effects of globalization in medical education, but these are complex phenomena to investigate. Socio-cultural activity theory seems a useful framework to study cultural complexity, because it matches current views on culture as a dynamic process situated in a social context, and has been valued in diverse fields for yielding rich understandings of complex issues and key factors involved. This paper explains how activity theory can be used in (cross-)cultural medical education research. We discuss activity theory's theoretical background and principles, and we show how these can be applied to the cultural research practice by discussing the steps involved in a cross-cultural study that we conducted, from formulating research questions to drawing conclusions. We describe how the activity system, the unit of analysis in activity theory, can serve as an organizing principle to grasp cultural complexity. We end with reflections on the theoretical and practical use of activity theory for cultural research and note that it is not a shortcut to capture cultural complexity: it is a challenge for researchers to determine the boundaries of their study and to analyze and interpret the dynamics of the activity system. PMID:24590549

  2. Using Student Development Theories as Conceptual Frameworks in Leadership Education

    ERIC Educational Resources Information Center

    Owen, Julie E.

    2012-01-01

    Theories of student learning and development are particularly important in leadership education because they make prescriptions about how people can adopt increasingly complex ways of being, knowing, and doing--essential forms of development for leadership learning. Increasingly, there is a call for leadership educators to adopt interdisciplinary…

  3. Aspects of Theories, Frameworks and Paradigms in Mathematics Education Research

    ERIC Educational Resources Information Center

    Stoilescu, Dorian

    2016-01-01

    This article discusses major theoretical debates and paradigms from the last decades in general education and their specific influences in mathematics education contexts. Behaviourism, cognitive science, constructivism, situated cognition, critical theory, place-based learning, postmodernism and poststructuralism and their significant aspects in…

  4. Generalizability Theory as a Unifying Framework of Measurement Reliability in Adolescent Research

    ERIC Educational Resources Information Center

    Fan, Xitao; Sun, Shaojing

    2014-01-01

    In adolescence research, the treatment of measurement reliability is often fragmented, and it is not always clear how different reliability coefficients are related. We show that generalizability theory (G-theory) is a comprehensive framework of measurement reliability, encompassing all other reliability methods (e.g., Pearson "r,"…

  5. Social Exchange Theory as a Conceptual Framework for Teaching the Sociological Perspective.

    ERIC Educational Resources Information Center

    O'Brien, Jodi A.; Kollock, Peter

    1991-01-01

    Uses social exchange theory as a conceptual framework for developing the sociological imagination. Explains this counters a trend toward an emphasis on social forces as behavioral determinants and the omission of values in the classroom. States exchange theory emphasizes how individual action collectively changes the social structure. Applies…

  6. Online Asynchronous Threaded Discussions: Good Enough to Advance Students through the Proximal Zone of Activity Theory?

    ERIC Educational Resources Information Center

    Maurino, Paula San Millan

    2007-01-01

    This paper presents a study which involved researching student interaction and participation under the lens of Activity Theory and Social Computing. Activity Theory is a philosophical framework that integrates the objective, the sociocultural, and the ecological, while Social Computing describes any type of computing application in which software…

  7. Pattern activation/recognition theory of mind

    PubMed Central

    du Castel, Bertrand

    2015-01-01

    In his 2012 book How to Create a Mind, Ray Kurzweil defines a “Pattern Recognition Theory of Mind” that states that the brain uses millions of pattern recognizers, plus modules to check, organize, and augment them. In this article, I further the theory to go beyond pattern recognition and include also pattern activation, thus encompassing both sensory and motor functions. In addition, I treat checking, organizing, and augmentation as patterns of patterns instead of separate modules, therefore handling them the same as patterns in general. Henceforth I put forward a unified theory I call “Pattern Activation/Recognition Theory of Mind.” While the original theory was based on hierarchical hidden Markov models, this evolution is based on their precursor: stochastic grammars. I demonstrate that a class of self-describing stochastic grammars allows for unifying pattern activation, recognition, organization, consistency checking, metaphor, and learning, into a single theory that expresses patterns throughout. I have implemented the model as a probabilistic programming language specialized in activation/recognition grammatical and neural operations. I use this prototype to compute and present diagrams for each stochastic grammar and corresponding neural circuit. I then discuss the theory as it relates to artificial network developments, common coding, neural reuse, and unity of mind, concluding by proposing potential paths to validation. PMID:26236228

  8. Pattern activation/recognition theory of mind.

    PubMed

    du Castel, Bertrand

    2015-01-01

    In his 2012 book How to Create a Mind, Ray Kurzweil defines a "Pattern Recognition Theory of Mind" that states that the brain uses millions of pattern recognizers, plus modules to check, organize, and augment them. In this article, I further the theory to go beyond pattern recognition and include also pattern activation, thus encompassing both sensory and motor functions. In addition, I treat checking, organizing, and augmentation as patterns of patterns instead of separate modules, therefore handling them the same as patterns in general. Henceforth I put forward a unified theory I call "Pattern Activation/Recognition Theory of Mind." While the original theory was based on hierarchical hidden Markov models, this evolution is based on their precursor: stochastic grammars. I demonstrate that a class of self-describing stochastic grammars allows for unifying pattern activation, recognition, organization, consistency checking, metaphor, and learning, into a single theory that expresses patterns throughout. I have implemented the model as a probabilistic programming language specialized in activation/recognition grammatical and neural operations. I use this prototype to compute and present diagrams for each stochastic grammar and corresponding neural circuit. I then discuss the theory as it relates to artificial network developments, common coding, neural reuse, and unity of mind, concluding by proposing potential paths to validation. PMID:26236228

  9. The potential of critical social theory as an educational framework for people with epilepsy.

    PubMed

    Bennett, Louise; Bergin, Michael; Wells, John S G

    2016-01-01

    Effective education can support people with epilepsy to develop the attributes and skills required to function as equal partners with clinical service providers, make informed decisions, and competently self-manage their healthcare. However, despite knowledge deficits, unmet information needs, and a poor sense of empowerment, the study of education for people with epilepsy is often neglected and is a poorly understood component of holistic practice within epilepsy healthcare. Historically, the only debate with regard to education and people with epilepsy has been guided either within a positivist or within a constructivist philosophy. We argue that new pedagogies are warranted, recognizing the views of people with epilepsy regarding their illness. Therefore, this paper explores the potential of an educational framework for people with epilepsy based upon critical social theory (CST). By utilizing a CST approach for education, people with epilepsy are engaged with as active 'participants'. This is a key difference that distinguishes CST from other metatheoretical frameworks. It has the potential to support people with epilepsy to acquire the skills and confidence to manage the biopsychosocial challenges associated with their condition. PMID:26687291

  10. Theory of Change: a theory-driven approach to enhance the Medical Research Council's framework for complex interventions

    PubMed Central

    2014-01-01

    Background The Medical Research Councils’ framework for complex interventions has been criticized for not including theory-driven approaches to evaluation. Although the framework does include broad guidance on the use of theory, it contains little practical guidance for implementers and there have been calls to develop a more comprehensive approach. A prospective, theory-driven process of intervention design and evaluation is required to develop complex healthcare interventions which are more likely to be effective, sustainable and scalable. Methods We propose a theory-driven approach to the design and evaluation of complex interventions by adapting and integrating a programmatic design and evaluation tool, Theory of Change (ToC), into the MRC framework for complex interventions. We provide a guide to what ToC is, how to construct one, and how to integrate its use into research projects seeking to design, implement and evaluate complex interventions using the MRC framework. We test this approach by using ToC within two randomized controlled trials and one non-randomized evaluation of complex interventions. Results Our application of ToC in three research projects has shown that ToC can strengthen key stages of the MRC framework. It can aid the development of interventions by providing a framework for enhanced stakeholder engagement and by explicitly designing an intervention that is embedded in the local context. For the feasibility and piloting stage, ToC enables the systematic identification of knowledge gaps to generate research questions that strengthen intervention design. ToC may improve the evaluation of interventions by providing a comprehensive set of indicators to evaluate all stages of the causal pathway through which an intervention achieves impact, combining evaluations of intervention effectiveness with detailed process evaluations into one theoretical framework. Conclusions Incorporating a ToC approach into the MRC framework holds promise for

  11. The ICAP Framework: Linking Cognitive Engagement to Active Learning Outcomes

    ERIC Educational Resources Information Center

    Chi, Michelene T. H.; Wylie, Ruth

    2014-01-01

    This article describes the ICAP framework that defines cognitive engagement activities on the basis of students' overt behaviors and proposes that engagement behaviors can be categorized and differentiated into one of four modes: "Interactive," "Constructive," "Active," and "Passive." The ICAP…

  12. A Lightweight Hierarchical Activity Recognition Framework Using Smartphone Sensors

    PubMed Central

    Han, Manhyung; Bang, Jae Hun; Nugent, Chris; McClean, Sally; Lee, Sungyoung

    2014-01-01

    Activity recognition for the purposes of recognizing a user's intentions using multimodal sensors is becoming a widely researched topic largely based on the prevalence of the smartphone. Previous studies have reported the difficulty in recognizing life-logs by only using a smartphone due to the challenges with activity modeling and real-time recognition. In addition, recognizing life-logs is difficult due to the absence of an established framework which enables the use of different sources of sensor data. In this paper, we propose a smartphone-based Hierarchical Activity Recognition Framework which extends the Naïve Bayes approach for the processing of activity modeling and real-time activity recognition. The proposed algorithm demonstrates higher accuracy than the Naïve Bayes approach and also enables the recognition of a user's activities within a mobile environment. The proposed algorithm has the ability to classify fifteen activities with an average classification accuracy of 92.96%. PMID:25184486

  13. Psychosocial Factors and Theory in Physical Activity Studies in Minorities

    PubMed Central

    Mama, Scherezade K.; McNeill, Lorna H.; McCurdy, Sheryl A.; Evans, Alexandra E.; Diamond, Pamela M.; Adamus-Leach, Heather J.; Lee, Rebecca E.

    2015-01-01

    Objectives To summarize the effectiveness of interventions targeting psychosocial factors to increase physical activity (PA) among ethnic minority adults and explore theory use in PA interventions. Methods Studies (N = 11) were identified through a systematic review and targeted African American/Hispanic adults, specific psychosocial factors, and PA. Data were extracted using a standard code sheet and the Theory Coding Scheme. Results Social support was the most common psychosocial factor reported, followed by motivational readiness, and self-efficacy, as being associated with increased PA. Only 7 studies explicitly reported using a theoretical framework. Conclusions Future efforts should explore theory use in PA interventions and how integration of theoretical constructs, including psychosocial factors, increases PA. PMID:25290599

  14. Bayesian inference and decision theory - A framework for decision making in natural resource management

    USGS Publications Warehouse

    Dorazio, R.M.; Johnson, F.A.

    2003-01-01

    Bayesian inference and decision theory may be used in the solution of relatively complex problems of natural resource management, owing to recent advances in statistical theory and computing. In particular, Markov chain Monte Carlo algorithms provide a computational framework for fitting models of adequate complexity and for evaluating the expected consequences of alternative management actions. We illustrate these features using an example based on management of waterfowl habitat.

  15. Changing Investment in Activities and Interests in Elders' Lives: Theory and Measurement

    ERIC Educational Resources Information Center

    Adams, Kathryn Betts

    2004-01-01

    Socioemotional selectivity and gerotranscendence, newer theories with roots in the disengagement theory of aging, provided the theoretical framework for a new measure of perceived change in investment in a variety of pursuits. The 30-item Change in Activity and Interest Index (CAII) was given to a sample of 327 outpatients aged 65-94. Items with…

  16. An Activity Theory Approach to Analyze Barriers to a Virtual Management Information Systems (MIS) Curriculum

    ERIC Educational Resources Information Center

    Jaradat, Suhair; Qablan, Ahmad; Barham, Areej

    2011-01-01

    This paper explains how the activity theory is used as a framework to analyze the barriers to a virtual Management Information Stream (MIS) Curriculum in Jordanian schools, from both the sociocultural and pedagogical perspectives. Taking the activity system as a unit of analysis, this study documents the processes by which activities shape and are…

  17. A Longitudinal Examination of Adolescent Career Planning and Exploration Using a Social Cognitive Career Theory Framework

    ERIC Educational Resources Information Center

    Rogers, Mary E.; Creed, Peter A.

    2011-01-01

    This study used social cognitive career theory (Lent, Brown, & Hackett, 1994), as a framework to investigate predictors of career choice actions, operationalised as career planning and career exploration. The model was tested cross-sectionally and longitudinally with 631 high school students enrolled in Grades 10-12. Students completed measures of…

  18. Argumentation, Dialogue Theory, and Probability Modeling: Alternative Frameworks for Argumentation Research in Education

    ERIC Educational Resources Information Center

    Nussbaum, E. Michael

    2011-01-01

    Toulmin's model of argumentation, developed in 1958, has guided much argumentation research in education. However, argumentation theory in philosophy and cognitive science has advanced considerably since 1958. There are currently several alternative frameworks of argumentation that can be useful for both research and practice in education. These…

  19. Development of a Brief Measure of Career Development Influences Based on the Systems Theory Framework

    ERIC Educational Resources Information Center

    Bridgstock, Ruth

    2007-01-01

    This paper documents the initial development and validation of a brief quantitative measure of career development influences based on the Systems Theory Framework (STF) of career development (McMahon & Patton, 1995; Patton & McMahon, 1997, 1999, 2006). Initial exploratory factor analyses of pilot study data revealed a six-factor structure based on…

  20. The Selective Cue Integration Framework: A Theory of Postidentification Witness Confidence Assessment

    ERIC Educational Resources Information Center

    Charman, Steve D.; Carlucci, Marianna; Vallano, Jon; Gregory, Amy Hyman

    2010-01-01

    The current manuscript proposes a theory of how witnesses assess their confidence following a lineup identification, called the selective cue integration framework (SCIF). Drawing from past research on the postidentification feedback effect, the SCIF details a three-stage process of confidence assessment that is based largely on a…

  1. Teaching Evaluation from an Experiential Framework: Connecting Theory and Organizational Development with Grant Making

    ERIC Educational Resources Information Center

    Kelly, Melissa A.; Kaczynski, Dan

    2008-01-01

    The authors present an approach for educating future evaluators by connecting evaluation theory and practice, organizational development, and grant making through experiential learning. They position this discussion on the conceptual framework of a newly developed graduate-level evaluation course, Advanced Program Development and Evaluation, which…

  2. The Power of Social Theory: The Anti-Colonial Discursive Framework.

    ERIC Educational Resources Information Center

    Sefa Dei, George J.; Asgharzadeh, Alireza

    2001-01-01

    Introduces the anti-colonial discourse as a guiding framework for forming alliances and partnerships among anti-oppression activists in academia and the larger society. Asserts that the anti-colonial discourse seeks to reclaim a new independent space strongly connected to other theories, such as Marxist, feminist, and deconstructionist. Describes…

  3. Towards a Research Framework for Race in Education: Critical Race Theory and Judith Butler

    ERIC Educational Resources Information Center

    Chadderton, Charlotte

    2013-01-01

    There has been much debate around the extent to which post-structuralist theory can be applied to critical research. In this article, it is argued that aspects of the two approaches can be combined, resulting in productive tensions that point towards a possible new framework for researching race and racism in education in the UK. The article…

  4. Facilitator Presence and Identity in Online Discourse: Use of Positioning Theory as an Analytic Framework

    ERIC Educational Resources Information Center

    Dennen, Vanessa P.

    2011-01-01

    In this study, positioning theory was used as a theoretical framework for analyzing facilitator presence and identity in online discussion transcripts. The study has two purposes. First, the study provides a description of naturally occurring facilitator positioning by facilitators and students in two online and two blended classes. Second, it…

  5. Understanding Critical Race Theory as a Framework in Higher Educational Research

    ERIC Educational Resources Information Center

    Savas, Gokhan

    2014-01-01

    This paper reviews the existing literature to discuss how critical race theory has been applied as a theoretical framework to higher educational research in the United States and what its contributions are. To provide necessary context, I will discuss race and racism in the United States, the background of US higher education in relation to race,…

  6. Integrating Theory and Practice to Increase Scientific Workforce Diversity: A Framework for Career Development in Graduate Research Training

    PubMed Central

    Byars-Winston, Angela; Gutierrez, Belinda; Topp, Sharon; Carnes, Molly

    2011-01-01

    Few, if any, educational interventions intended to increase underrepresented minority (URM) graduate students in biological and behavioral sciences are informed by theory and research on career persistence. Training and Education to Advance Minority Scholars in Science (TEAM-Science) is a program funded by the National Institute of General Medical Sciences at the University of Wisconsin–Madison with the twin goals of increasing the number of URM students entering and completing a PhD in BBS and increasing the number of these students who pursue academic careers. A framework for career development in graduate research training is proposed using social cognitive career theory. Based on this framework, TEAM-Science has five core components: 1) mentor training for the research advisor, 2) eight consensus-derived fundamental competencies required for a successful academic career, 3) career coaching by a senior faculty member, 4) an individualized career development plan that aligns students’ activities with the eight fundamental competencies, and 5) a strengths, weaknesses, opportunities, and threats personal career analysis. This paper describes the theoretical framework used to guide development of these components, the research and evaluation plan, and early experience implementing the program. We discuss the potential of this framework to increase desired career outcomes for URM graduate trainees in mentored research programs and, thereby, strengthen the effectiveness of such interventions on participants’ career behaviors. PMID:22135370

  7. An Evolving Framework for Describing Student Engagement in Classroom Activities

    ERIC Educational Resources Information Center

    Azevedo, Flavio S.; diSessa, Andrea A.; Sherin, Bruce L.

    2012-01-01

    Student engagement in classroom activities is usually described as a function of factors such as human needs, affect, intention, motivation, interests, identity, and others. We take a different approach and develop a framework that models classroom engagement as a function of students' "conceptual competence" in the "specific content" (e.g., the…

  8. Pressure of massless hot scalar theory in the boundary effective theory framework

    SciTech Connect

    Bessa, A.; Brandt, F. T.; Carvalho, C. A. A. de; Fraga, E. S.

    2011-04-15

    We use the boundary effective theory approach to thermal field theory in order to calculate the pressure of a system of massless scalar fields with quartic interaction. The method naturally separates the infrared physics, and is essentially nonperturbative. To lowest order, the main ingredient is the solution of the free Euler-Lagrange equation with nontrivial (time) boundary conditions. We derive a resummed pressure, which is in good agreement with recent calculations found in the literature, following a very direct and compact procedure.

  9. Activity Theory and Language Teacher Agency

    ERIC Educational Resources Information Center

    Feryok, Anne

    2012-01-01

    This article takes a broadly sociocultural perspective on the development of an Armenian English as a foreign language (EFL) teacher. It focuses on how experiences and actions outside the professional development classroom influence language teacher agency. The paper is framed within activity theory and specifically draws on Galperin's orienting…

  10. Cultural Historical Activity Theory and Professional Learning

    ERIC Educational Resources Information Center

    Daniels, Harry

    2004-01-01

    In this article I will discuss the route by which I came to work with Cultural Historical Activity Theory (CHAT). The brief tracing of my own biography will highlight theoretical and methodological milestones. I will then discuss my current work, with colleagues, on approaches to investigating and improving the learning of professionals who are…

  11. Linking Complexity with Cultural Historical Activity Theory

    ERIC Educational Resources Information Center

    McMurtry, Angus

    2006-01-01

    This paper explores the similarities and differences between complexity science's and cultural-historical activity theory's understandings of human learning. Notable similarities include their emphasis on the importance of social systems or collectives in understanding human knowledge and practices, as well as their characterization of systems'…

  12. Analyzing learning during Peer Instruction dialogues: A resource activation framework

    NASA Astrophysics Data System (ADS)

    Wood, Anna K.; Galloway, Ross K.; Hardy, Judy; Sinclair, Christine M.

    2014-12-01

    Peer Instruction (PI) is an evidence based pedagogy commonly used in undergraduate physics instruction. When asked questions designed to test conceptual understanding, it has been observed that the proportion of students choosing the correct answer increases following peer discussion; however, relatively little is known about what takes place during these discussions or how they are beneficial to the processes of learning physics [M. C. James and S. Willoughby, Am. J. Phys. 79, 123 (2011)]. In this paper a framework for analyzing PI discussions developed through the lens of the "resources model" [D. Hammer, Am. J. Phys. 64, 1316 (1996); D. Hammer et al., Information Age Publishing (2005)] is proposed. A central hypothesis for this framework is that the dialogue with peers plays a crucial role in activating appropriate cognitive resources, enabling the students to see the problem differently, and therefore to answer the questions correctly. This framework is used to gain greater insights into the PI discussions of first year undergraduate physics students at the University of Edinburgh, UK, which were recorded using Livescribe Smartpens. Analysis of the dialogues revealed three different types of resource activation corresponding to increasing cognitive grain size. These were activation of knowledge elements, activation of linkages between knowledge elements, and activation of control structures (epistemic games and epistemological frames). Three case studies are examined to illustrate the role that peer dialogue plays in the activation of these cognitive resources in a PI session. The implications for pedagogical practice are discussed.

  13. An economic framework for understanding physical activity and eating behaviors.

    PubMed

    Cawley, John

    2004-10-01

    This paper offers an economic framework of human behavior with respect to physical activity and nutrition. Economics offers useful insights into these behaviors because it is the study of how people allocate their scarce resources of time and money to maximize their lifetime happiness. This paper outlines the criteria for policy interventions from an economic perspective and also considers arguments for policy intervention that are not based on economic considerations. The implications of the economic framework are summarized and its limitations are described. PMID:15450622

  14. Transition path theory analysis of c-Src kinase activation.

    PubMed

    Meng, Yilin; Shukla, Diwakar; Pande, Vijay S; Roux, Benoît

    2016-08-16

    Nonreceptor tyrosine kinases of the Src family are large multidomain allosteric proteins that are crucial to cellular signaling pathways. In a previous study, we generated a Markov state model (MSM) to simulate the activation of c-Src catalytic domain, used as a prototypical tyrosine kinase. The long-time kinetics of transition predicted by the MSM was in agreement with experimental observations. In the present study, we apply the framework of transition path theory (TPT) to the previously constructed MSM to characterize the main features of the activation pathway. The analysis indicates that the activating transition, in which the activation loop first opens up followed by an inward rotation of the αC-helix, takes place via a dense set of intermediate microstates distributed within a fairly broad "transition tube" in a multidimensional conformational subspace connecting the two end-point conformations. Multiple microstates with negligible equilibrium probabilities carry a large transition flux associated with the activating transition, which explains why extensive conformational sampling is necessary to accurately determine the kinetics of activation. Our results suggest that the combination of MSM with TPT provides an effective framework to represent conformational transitions in complex biomolecular systems. PMID:27482115

  15. Dynamo theory prediction of solar activity

    NASA Technical Reports Server (NTRS)

    Schatten, Kenneth H.

    1988-01-01

    The dynamo theory technique to predict decadal time scale solar activity variations is introduced. The technique was developed following puzzling correlations involved with geomagnetic precursors of solar activity. Based upon this, a dynamo theory method was developed to predict solar activity. The method was used successfully in solar cycle 21 by Schatten, Scherrer, Svalgaard, and Wilcox, after testing with 8 prior solar cycles. Schatten and Sofia used the technique to predict an exceptionally large cycle, peaking early (in 1990) with a sunspot value near 170, likely the second largest on record. Sunspot numbers are increasing, suggesting that: (1) a large cycle is developing, and (2) that the cycle may even surpass the largest cycle (19). A Sporer Butterfly method shows that the cycle can now be expected to peak in the latter half of 1989, consistent with an amplitude comparable to the value predicted near the last solar minimum.

  16. An Alienation-Based Framework for Student Experience in Higher Education: New Interpretations of Past Observations in Student Learning Theory

    ERIC Educational Resources Information Center

    Barnhardt, Bradford; Ginns, Paul

    2014-01-01

    This article orients a recently proposed alienation-based framework for student learning theory (SLT) to the empirical basis of the approaches to learning perspective. The proposed framework makes new macro-level interpretations of an established micro-level theory, across three levels of interpretation: (1) a context-free psychological state…

  17. Using the Theory of Planned Behavior as a Framework for the Evaluation of a Professional Development Workshop

    PubMed Central

    PATTERSON, ROBIN R.

    2001-01-01

    This purpose of this study was to use a theoretical framework based on several decades of attitudinal research to assess the intentions of Microbial Discovery Workshop participants to incorporate the inquiry activities presented at the workshop into their curricula, to evaluate the participants actual use of these activities after the workshop, and to uncover the barriers and enablers the participants faced in doing so. As a framework, the theory of planned behavior was ascertained to be an appropriate means of assessment and it was revealed that participants’ intention to use the workshop activities significantly correlated with their actual use. The participants’ attitudes toward using the activities influenced their use more than the participants’ perceptions of the social pressures that would influence their decision to use the activities or their belief as to how easy or difficult it would be to incorporate a given activity. The participants were found to be highly self-efficacious pertaining to their ability to implement the activities, but perceived self-efficacy was not a significant predictor of the participants’ intentions to incorporate the activities into their teaching-learning repertoire. The study also uncovered other behaviors the participants displayed as a result of attending the workshop consistent with the goals and objectives of the workshop organizers. PMID:23653542

  18. Feminist Framework Plus: Knitting Feminist Theories of Rape Etiology Into a Comprehensive Model.

    PubMed

    McPhail, Beverly A

    2016-07-01

    The radical-liberal feminist perspective on rape posits that the assault is motivated by power and control rather than sexual gratification and is a violent rather than a sexual act. However, rape is a complex act. Relying on only one early strand of feminist thought to explain the etiology of rape limits feminists' understanding of rape and the practice based upon the theory. The history of the adoption of the "power, not sex" theory is presented and the model critiqued. A more integrated model is developed and presented, the Feminist Framework Plus, which knits together five feminist theories into a comprehensive model that better explains the depth and breadth of the etiology of rape. Empirical evidence that supports each theory is detailed as well as the implications of the model on service provision, education, and advocacy. PMID:26018209

  19. Researching Contradictions: Cultural Historical Activity Theory Research (CHAT) in the English Classroom

    ERIC Educational Resources Information Center

    Thompson, Ian

    2015-01-01

    This article argues that Cultural Historical Activity Theory (CHAT) is an appropriate theoretical and methodological framework for researchers in English interested in the social contexts of culture and its relationship with the formation of mind and activity in the English classroom. Two key concepts in Vygotsky's thought central to understanding…

  20. Exploration of Tensions in a Mobile-Technology Supported Fieldtrip: An Activity Theory Perspective

    ERIC Educational Resources Information Center

    Lai, Chih-Hung; Chen, Fei-Ching; Yang, Jie-Chi

    2014-01-01

    The purpose of this study was to analyze how mobile technologies were incorporated and implemented in an outdoor learning activity. Two classes of primary school students participated in the experiment. Using activity theory as an analytical framework, it is found that underlying tensions provided rich insights into system dynamics and that…

  1. Understanding Preschool Emergent Science in a Cultural Historical Context through Activity Theory

    ERIC Educational Resources Information Center

    Sundberg, Bodil; Areljung, Sofie; Due, Karin; Ekström, Kenneth; Ottander, Christina; Tellgren, Britt

    2016-01-01

    The aim of this study is to explore how cultural factors interact with preschool teachers' shaping of activities with science content, and also how Activity Theory (AT) as a theoretical framework can be useful for examining interrelations within preschool systems. Qualitative data was collected from three preschools in the form of guided group…

  2. Integrating Social Activity Theory and Critical Discourse Analysis: A Multilayered Methodological Model for Examining Knowledge Mediation in Mentoring

    ERIC Educational Resources Information Center

    Becher, Ayelet; Orland-Barak, Lily

    2016-01-01

    This study suggests an integrative qualitative methodological framework for capturing complexity in mentoring activity. Specifically, the model examines how historical developments of a discipline direct mentors' mediation of professional knowledge through the language that they use. The model integrates social activity theory and a framework of…

  3. Grounding theories of W(e)Learn: a framework for online interprofessional education.

    PubMed

    Casimiro, Lynn; MacDonald, Colla J; Thompson, Terrie Lynn; Stodel, Emma J

    2009-07-01

    Interprofessional care (IPC) is a prerequisite for enhanced communication between healthcare team members, improved quality of care, and better outcomes for patients. A move to an IPC model requires changing the learning experiences of healthcare providers during and after their qualification program. With the rapid growth of online and blended approaches to learning, an educational framework that explains how to construct quality learning events to provide IPC is pressing. Such a framework would offer a quality standard to help educators design, develop, deliver, and evaluate online interprofessional education (IPE) programs. IPE is an extremely delicate process due to issues related to knowledge, status, power, accountability, personality traits, and culture that surround IPC. In this paper, a review of the pertinent literature that would inform the development of such a framework is presented. The review covers IPC, IPE, learning theories, and eLearning in healthcare. PMID:19517287

  4. The PROactive innovative conceptual framework on physical activity

    PubMed Central

    Dobbels, Fabienne; de Jong, Corina; Drost, Ellen; Elberse, Janneke; Feridou, Chryssoula; Jacobs, Laura; Rabinovich, Roberto; Frei, Anja; Puhan, Milo A.; de Boer, Willem I.; van der Molen, Thys; Williams, Kate; Pinnock, Hillary; Troosters, Thierry; Karlsson, Niklas; Kulich, Karoly; Rüdell, Katja; Brindicci, Caterina; Higenbottam, Tim; Troosters, Thierry; Dobbels, Fabienne; Decramer, Marc; Tabberer, Margaret; Rabinovich, Roberto A; MacNee, William; Vogiatzis, Ioannis; Polkey, Michael; Hopkinson, Nick; Garcia-Aymerich, Judith; Puhan, Milo; Frei, Anja; van der Molen, Thys; de Jong, Corina; de Boer, Pim; Jarrod, Ian; McBride, Paul; Kamel, Nadia; Rudell, Katja; Wilson, Frederick J.; Ivanoff, Nathalie; Kulich, Karoly; Glendenning, Alistair; Karlsson, Niklas X.; Corriol-Rohou, Solange; Nikai, Enkeleida; Erzen, Damijan

    2014-01-01

    Although physical activity is considered an important therapeutic target in chronic obstructive pulmonary disease (COPD), what “physical activity” means to COPD patients and how their perspective is best measured is poorly understood. We designed a conceptual framework, guiding the development and content validation of two patient reported outcome (PRO) instruments on physical activity (PROactive PRO instruments). 116 patients from four European countries with diverse demographics and COPD phenotypes participated in three consecutive qualitative studies (63% male, age mean±sd 66±9 years, 35% Global Initiative for Chronic Obstructive Lung Disease stage III–IV). 23 interviews and eight focus groups (n = 54) identified the main themes and candidate items of the framework. 39 cognitive debriefings allowed the clarity of the items and instructions to be optimised. Three themes emerged, i.e. impact of COPD on amount of physical activity, symptoms experienced during physical activity, and adaptations made to facilitate physical activity. The themes were similar irrespective of country, demographic or disease characteristics. Iterative rounds of appraisal and refinement of candidate items resulted in 30 items with a daily recall period and 34 items with a 7-day recall period. For the first time, our approach provides comprehensive insight on physical activity from the COPD patients’ perspective. The PROactive PRO instruments’ content validity represents the pivotal basis for empirically based item reduction and validation. PMID:25034563

  5. Internally contracted multireference coupled-cluster theory in a multistate framework

    NASA Astrophysics Data System (ADS)

    Aoto, Yuri Alexandre; Köhn, Andreas

    2016-02-01

    The internally contracted multireference coupled cluster (icMRCC) theory is reexamined in a multistate framework. The new derivation starts from the Bloch equations employing a wave operator similar to the one originally employed by Jeziorski and Monkhorst [Phys. Rev. A 24, 1668 (1981)], but allows for a multideterminantal model-space basis. The resulting working equations are a generalization of state-universal multireference coupled-cluster (SU-MRCC) theory. In the case of truncated cluster operators, energies and wave functions depend on the choice of the model-space basis. It is shown that the state-specific solutions of the original icMRCC theory exactly diagonalize the effective Hamiltonian of the multistate theory and thus decouple the multistate equations. While this in principle means that icMRCC is a multistate theory, we find that truncated icMRCC theory still shows minor artifacts close to avoided crossings, which can be removed by considering a true multistate ansatz. The results also shed new light on the orbital variance of the original SU-MRCC theory.

  6. On the rationality of cycling in the Theory of Moves framework

    NASA Astrophysics Data System (ADS)

    Olsen, Jolie; Sen, Sandip

    2014-04-01

    Theory of Moves (TOM) is a novel approach to game theory for determining rational strategies during the play of dynamic games [Brams, S J. (1994). Theory of moves. Cambridge, UK: Cambridge University Press]. While alternate models such as normal form games exist, players of these games are limited to single shot interactions with each other, but within TOM, sequences of moves and counter moves are allowed. As a consequence of this framework potential cyclic behaviour may arise. Unfortunately, standard TOM framework suggests that players do not move from the initial state if the possibility of cyclic behaviour is detected. However, in a plethora of real life scenarios, cycling can benefit a player over time. We first extend the TOM framework by allowing players to choose how much time to stay in each state while specifying time limits for moves. This generalisation allows for cycling behaviour in addition to normal, acyclic TOM play. We present additional rationality rules to handle the choice of move time and cyclic play and identify conditions for the existence of solutions that involve cycles. Moreover, if solutions do exist, equilibrium are determined so a player can predict the rational outcome upon engaging a cycle. A variety of time constraints on move times are investigated and the effects of these contrasts on the solution space and equilibrium are analysed.

  7. Coalescent: an open-science framework for importance sampling in coalescent theory

    PubMed Central

    Spouge, John L.

    2015-01-01

    Background. In coalescent theory, computer programs often use importance sampling to calculate likelihoods and other statistical quantities. An importance sampling scheme can exploit human intuition to improve statistical efficiency of computations, but unfortunately, in the absence of general computer frameworks on importance sampling, researchers often struggle to translate new sampling schemes computationally or benchmark against different schemes, in a manner that is reliable and maintainable. Moreover, most studies use computer programs lacking a convenient user interface or the flexibility to meet the current demands of open science. In particular, current computer frameworks can only evaluate the efficiency of a single importance sampling scheme or compare the efficiencies of different schemes in an ad hoc manner. Results. We have designed a general framework (http://coalescent.sourceforge.net; language: Java; License: GPLv3) for importance sampling that computes likelihoods under the standard neutral coalescent model of a single, well-mixed population of constant size over time following infinite sites model of mutation. The framework models the necessary core concepts, comes integrated with several data sets of varying size, implements the standard competing proposals, and integrates tightly with our previous framework for calculating exact probabilities. For a given dataset, it computes the likelihood and provides the maximum likelihood estimate of the mutation parameter. Well-known benchmarks in the coalescent literature validate the accuracy of the framework. The framework provides an intuitive user interface with minimal clutter. For performance, the framework switches automatically to modern multicore hardware, if available. It runs on three major platforms (Windows, Mac and Linux). Extensive tests and coverage make the framework reliable and maintainable. Conclusions. In coalescent theory, many studies of computational efficiency consider only

  8. Framework for coordination of activities in dynamic situations

    NASA Astrophysics Data System (ADS)

    Franke, Jörn; Charoy, François; El Khoury, Paul

    2013-02-01

    Recent disasters, such as Hurricane Katrina in 2005, have shown several issues for the coordination of human activities in these dynamic situations. Contemporary tools for the coordination used in the disaster response, such as e-mail, Whiteboards or phones, only allow for unstructured coordination, which can cause coordination problems. Hence, we discuss about the current information systems for coordinating the activities in a structured manner and identify their weaknesses in the context of a process modelling effort conducted together with experienced disaster managers. Afterwards, we propose a framework for coordination of activities in dynamic situations. The framework presented in this paper has been implemented as an extension to an open collaboration service. This shows how it can be used in the context of other tools required for disaster response management, such as maps, pictures or videos of the situation. The work described here is the foundation for enabling inter-organisational coordination of activities relevant in other domains, e.g. enterprise support processes, production processes or distributed software development projects. Furthermore, comments by disaster managers show that the concepts are relevant for their work. The expected impact is a more effective and efficient coordination of human activities in dynamic situations by structuring what needs to be coordinated.

  9. An Extensible, User- Modifiable Framework for Planning Activities

    NASA Technical Reports Server (NTRS)

    Joshing, Joseph C.; Abramyan, Lucy; Mickelson, Megan C.; Wallick, Michael N.; Kurien, James A.; Crockett, Thomasa M.; Powell, Mark W.; Pyrzak, Guy; Aghevli, Arash

    2013-01-01

    This software provides a development framework that allows planning activities for the Mars Science Laboratory rover to be altered at any time, based on changes of the Activity Dictionary. The Activity Dictionary contains the definition of all activities that can be carried out by a particular asset (robotic or human). These definitions (and combinations of these definitions) are used by mission planners to give a daily plan of what a mission should do. During the development and course of the mission, the Activity Dictionary and actions that are going to be carried out will often be changed. Previously, such changes would require a change to the software and redeployment. Now, the Activity Dictionary authors are able to customize activity definitions, parameters, and resource usage without requiring redeployment. This software provides developers and end users the ability to modify the behavior of automatically generated activities using a script. This allows changes to the software behavior without incurring the burden of redeployment. This software is currently being used for the Mars Science Laboratory, and is in the process of being integrated into the LADEE (Lunar Atmosphere and Dust Environment Explorer) mission, as well as the International Space Station.

  10. Applying behavioral theories to invasive animal management: Towards an integrated framework.

    PubMed

    McLeod, Lynette J; Hine, Donald W; Please, Patricia M; Driver, Aaron B

    2015-09-15

    Invasive species wreak an estimated $1.4 trillion in damages globally, each year. To have any hope of reducing this damage, best-practice control strategies must incorporate behavior change interventions. Traditional interventions, based on the knowledge-transfer model, assume that if land managers are properly educated about risks and strategies, they will develop supportive attitudes and implement appropriate control strategies. However, the social sciences have produced a large number of behavioral models and frameworks that demonstrate that knowledge transfer, by itself, fails to change behavior. The challenge then lies in knowing which behavioral model to choose, and when, from a potentially overwhelming 'universe'. In this paper, we review nine behavior theories relevant to invasive species management. We then introduce the Behavior Change Wheel as a tool for integrating these theories into a single practical framework. This framework links drivers of and barriers to behavior change with intervention strategies and policies, in what we consider, from an applied perspective, to be an important advance. PMID:26151198

  11. Theory-Driven Intervention for Changing Personality: Expectancy Value Theory, Behavioral Activation, and Conscientiousness

    PubMed Central

    Magidson, Jessica F.; Roberts, Brent; Collado-Rodriguez, Anahi; Lejuez, C.W.

    2013-01-01

    Considerable evidence suggests that personality traits may be changeable, raising the possibility that personality traits most linked to health problems can be modified with intervention. A growing body of research suggests that problematic personality traits may be altered with behavioral intervention using a bottom-approach. That is, by targeting core behaviors that underlie personality traits with the goal of engendering new, healthier patterns of behavior that over time become automatized and manifest in changes in personality traits. Nevertheless, a bottom-up model for changing personality traits is somewhat diffuse and requires clearer integration of theory and relevant interventions to enable real clinical application. As such, this manuscript proposes a set of guiding principles for theory-driven modification of targeted personality traits using a bottom-up approach, focusing specifically on targeting the trait of conscientiousness using a relevant behavioral intervention, Behavioral Activation (BA), considered within the motivational framework of Expectancy Value Theory (EVT). We conclude with a real case example of the application of BA to alter behaviors counter to conscientiousness in a substance dependent patient, highlighting the EVT principles most relevant to the approach and the importance and viability of a theoretically-driven, bottom-up approach to changing personality traits. PMID:23106844

  12. The Dynamics of Online Communities in the Activity Theory Framework

    ERIC Educational Resources Information Center

    Baran, Bahar; Cagiltay, Kursat

    2010-01-01

    The aim of this study is to reveal how well online communities of practice (oCoPs) help teachers share explicit knowledge and bring their tacit knowledge to the surface. An Internet based oCoP platform called "The Professional Development Circle" (The PDC) was developed for this study. The study was conducted in two phases: 1) a mandatory…

  13. Modeling active memory: Experiment, theory and simulation

    NASA Astrophysics Data System (ADS)

    Amit, Daniel J.

    2001-06-01

    Neuro-physiological experiments on cognitively performing primates are described to argue that strong evidence exists for localized, non-ergodic (stimulus specific) attractor dynamics in the cortex. The specific phenomena are delay activity distributions-enhanced spike-rate distributions resulting from training, which we associate with working memory. The anatomy of the relevant cortex region and the physiological characteristics of the participating elements (neural cells) are reviewed to provide a substrate for modeling the observed phenomena. Modeling is based on the properties of the integrate-and-fire neural element in presence of an input current of Gaussian distribution. Theory of stochastic processes provides an expression for the spike emission rate as a function of the mean and the variance of the current distribution. Mean-field theory is then based on the assumption that spike emission processes in different neurons in the network are independent, and hence the input current to a neuron is Gaussian. Consequently, the dynamics of the interacting network is reduced to the computation of the mean and the variance of the current received by a cell of a given population in terms of the constitutive parameters of the network and the emission rates of the neurons in the different populations. Within this logic we analyze the stationary states of an unstructured network, corresponding to spontaneous activity, and show that it can be stable only if locally the net input current of a neuron is inhibitory. This is then tested against simulations and it is found that agreement is excellent down to great detail. A confirmation of the independence hypothesis. On top of stable spontaneous activity, keeping all parameters fixed, training is described by (Hebbian) modification of synapses between neurons responsive to a stimulus and other neurons in the module-synapses are potentiated between two excited neurons and depressed between an excited and a quiescent neuron

  14. a Multidisciplinary Analytical Framework for Studying Active Mobility Patterns

    NASA Astrophysics Data System (ADS)

    Orellana, D.; Hermida, C.; Osorio, P.

    2016-06-01

    Intermediate cities are urged to change and adapt their mobility systems from a high energy-demanding motorized model to a sustainable low-motorized model. In order to accomplish such a model, city administrations need to better understand active mobility patterns and their links to socio-demographic and cultural aspects of the population. During the last decade, researchers have demonstrated the potential of geo-location technologies and mobile devices to gather massive amounts of data for mobility studies. However, the analysis and interpretation of this data has been carried out by specialized research groups with relatively narrow approaches from different disciplines. Consequently, broader questions remain less explored, mainly those relating to spatial behaviour of individuals and populations with their geographic environment and the motivations and perceptions shaping such behaviour. Understanding sustainable mobility and exploring new research paths require an interdisciplinary approach given the complex nature of mobility systems and their social, economic and environmental impacts. Here, we introduce the elements for a multidisciplinary analytical framework for studying active mobility patterns comprised of three components: a) Methodological, b) Behavioural, and c) Perceptual. We demonstrate the applicability of the framework by analysing mobility patterns of cyclists and pedestrians in an intermediate city integrating a range of techniques, including: GPS tracking, spatial analysis, auto-ethnography, and perceptual mapping. The results demonstrated the existence of non-evident spatial behaviours and how perceptual features affect mobility. This knowledge is useful for developing policies and practices for sustainable mobility planning.

  15. Installing hydrolytic activity into a completely de novo protein framework.

    PubMed

    Burton, Antony J; Thomson, Andrew R; Dawson, William M; Brady, R Leo; Woolfson, Derek N

    2016-09-01

    The design of enzyme-like catalysts tests our understanding of sequence-to-structure/function relationships in proteins. Here we install hydrolytic activity predictably into a completely de novo and thermostable α-helical barrel, which comprises seven helices arranged around an accessible channel. We show that the lumen of the barrel accepts 21 mutations to functional polar residues. The resulting variant, which has cysteine-histidine-glutamic acid triads on each helix, hydrolyses p-nitrophenyl acetate with catalytic efficiencies that match the most-efficient redesigned hydrolases based on natural protein scaffolds. This is the first report of a functional catalytic triad engineered into a de novo protein framework. The flexibility of our system also allows the facile incorporation of unnatural side chains to improve activity and probe the catalytic mechanism. Such a predictable and robust construction of truly de novo biocatalysts holds promise for applications in chemical and biochemical synthesis. PMID:27554410

  16. Exploring Students' Perceptions about Learning in School: An Activity Theory Based Study

    ERIC Educational Resources Information Center

    Portnov-Neeman, Yelena; Barak, Moshe

    2013-01-01

    In the current study, we used Activity Theory as the conceptual framework for exploring students' perceptions about how learning in school is affected by the following five elements: Object, Tools, Rules, Community and Division of Labor. Data were collected by administrating a semi-structured questionnaire among 70 junior high school students and…

  17. Understanding Wikibook-Based Tensions in Higher Education: An Activity Theory Approach

    ERIC Educational Resources Information Center

    Karasavvidis, Ilias

    2010-01-01

    Research has indicated that the integration of wikis in higher education is very challenging. The present article focuses on the tensions emerging from the integration of a wikibook as a required assignment in an undergraduate course. Drawing on data from a case study, the article uses Activity Theory as a theoretical framework in order to…

  18. Transforming Pedagogy through Interactive Whiteboards: Using Activity Theory to Understand Tensions in Practice

    ERIC Educational Resources Information Center

    Sweeney, Trudy

    2010-01-01

    There has been considerable investment in the use of interactive whiteboard technology in Australia, particularly in primary schools. School leaders and teachers are seeking advice on effective ways to support teachers' pedagogical development to achieve the potential benefits of these devices. Using activity theory as a framework for lesson…

  19. Methodologies in Cultural-Historical Activity Theory: The Example of School-Based Development

    ERIC Educational Resources Information Center

    Postholm, May Britt

    2015-01-01

    Background and purpose: Relatively little research has been conducted on methodology within Cultural-Historical Activity Theory (CHAT). CHAT is mainly used as a framework for developmental processes. The purpose of this article is to discuss both focuses for research and research questions within CHAT and to outline methodologies that can be used…

  20. Using Activity Theory to Understand Intergenerational Play: The Case of Family Quest

    ERIC Educational Resources Information Center

    Siyahhan, Sinem; Barab, Sasha A.; Downton, Michael P.

    2010-01-01

    We implemented a five-week family program called "Family Quest" where parents and children ages 9 to 13 played Quest Atlantis, a multiuser 3D educational computer game, at a local after-school club for 90-minute sessions. We used activity theory as a conceptual and an analytical framework to study the nature of intergenerational play, the…

  1. Embedded-cluster calculations in a numeric atomic orbital density-functional theory framework

    SciTech Connect

    Berger, Daniel Oberhofer, Harald; Reuter, Karsten; Logsdail, Andrew J. Farrow, Matthew R.; Catlow, C. Richard A.; Sokol, Alexey A.; Sherwood, Paul; Blum, Volker

    2014-07-14

    We integrate the all-electron electronic structure code FHI-aims into the general ChemShell package for solid-state embedding quantum and molecular mechanical (QM/MM) calculations. A major undertaking in this integration is the implementation of pseudopotential functionality into FHI-aims to describe cations at the QM/MM boundary through effective core potentials and therewith prevent spurious overpolarization of the electronic density. Based on numeric atomic orbital basis sets, FHI-aims offers particularly efficient access to exact exchange and second order perturbation theory, rendering the established QM/MM setup an ideal tool for hybrid and double-hybrid level density functional theory calculations of solid systems. We illustrate this capability by calculating the reduction potential of Fe in the Fe-substituted ZSM-5 zeolitic framework and the reaction energy profile for (photo-)catalytic water oxidation at TiO{sub 2}(110)

  2. Hybrid framework based on evidence theory for blood cell image segmentation

    NASA Astrophysics Data System (ADS)

    Baghli, Ismahan; Nakib, Amir; Sellam, Elie; Benazzouz, Mourtada; Chikh, Amine; Petit, Eric

    2014-03-01

    The segmentation of microscopic images is an important issue in biomedical image processing. Many works can be found in the literature; however, there is not a gold standard method that is able to provide good results for all kinds of microscopic images. Then, authors propose methods for a given kind of microscopic images. This paper deals with new segmentation framework based on evidence theory, called ESA (Evidential Segmentation Algorithm) to segment blood cell images. The proposed algorithm allows solving the segmentation problem of blood cell images. Herein, our goal is to extract the components of a given cell image by using evidence theory, that allows more flexibility to classify the pixels. The obtained results showed the efficiency of the proposed algorithm compared to other competing methods.

  3. Fluctuation paraconductivity within the framework of time-dependent Ginzburg Landau theory

    NASA Astrophysics Data System (ADS)

    Damianov, Damian Ch.; Mishonov, Todor M.

    1997-04-01

    Above the critical temperatureTcthe fluctuations of the superconducting order parameter Ψ are described within the framework of time-dependent Ginzburt-Landua theory using Langevin's approach of stochastic differential equations. The excess Aslamazov-Larkin conductivity is derived as an improtant test example for the case of non interacting fluctuations. It is shown at what conditions the kinetic arguments can be successively derived. A fluctuation Hall conductivity σxy(fl)and Nernst coefficient νxy(fl)are calculated for the case of weak magnetic field. The comparison with the BCS will result by Varlamov and Livanov [A. A. Varlamov and D. V. Livanov, Phys. Lett. A 157, 519 (1991)] gives the final determination of all the coefficients of the phenomenological TDGL theory.

  4. Rethinking Distance Learning Activities: A Comparison of Transactional Distance Theory and Activity Theory

    ERIC Educational Resources Information Center

    Kang, Haijun; Gyorke, Allan S.

    2008-01-01

    Despite its invaluable guidance to distance education development, transactional distance (TD) theory is not seamlessly synchronised with current field practice and lacks a social component. After it has provided over 30 years of guidance, there is now a need to re-appraise TD's propositions about distance learning activities. The social-cultural…

  5. Theory and modeling of active brazing.

    SciTech Connect

    van Swol, Frank B.; Miller, James Edward; Lechman, Jeremy B.; Givler, Richard C.

    2013-09-01

    Active brazes have been used for many years to produce bonds between metal and ceramic objects. By including a relatively small of a reactive additive to the braze one seeks to improve the wetting and spreading behavior of the braze. The additive modifies the substrate, either by a chemical surface reaction or possibly by alloying. By its nature, the joining process with active brazes is a complex nonequilibrium non-steady state process that couples chemical reaction, reactant and product diffusion to the rheology and wetting behavior of the braze. Most of the these subprocesses are taking place in the interfacial region, most are difficult to access by experiment. To improve the control over the brazing process, one requires a better understanding of the melting of the active braze, rate of the chemical reaction, reactant and product diffusion rates, nonequilibrium composition-dependent surface tension as well as the viscosity. This report identifies ways in which modeling and theory can assist in improving our understanding.

  6. Behavioral aspects of clinical trials. An integrated framework from behavior theory.

    PubMed

    Morrow, G R; Hickok, J T; Burish, T G

    1994-11-01

    A less-than-optimal proportion of patients with cancer are entered into National Cancer Institute-sponsored clinical trials. This article reviews the literature on accrual in oncology clinical trials to characterize the extent of the problem, identify reasons for low accrual, and suggest ways to promote accrual. Four well known theories of health behavior (the Health Belief Model, Subjective Expected Utility Theory, Protection Motivation Theory, and the Theory of Reasoned Action) point to central concepts involved in understanding patient health-related behavior: (1) the probability that an unwelcomed health event will happen to a patient, (2) the severity of that event if it does occur, (3) the effectiveness of a particular behavior (such as taking part in a clinical trial) to modify the severity, and (4) the cost of adopting that behavior. These concepts form a framework for integrating the available information about accrual to clinical oncology trials. Patient and physician factors previously related to clinical trials suggest specific recommendations for increasing accrual to clinical oncology trials. PMID:7954285

  7. TEAK: topology enrichment analysis framework for detecting activated biological subpathways.

    PubMed

    Judeh, Thair; Johnson, Cole; Kumar, Anuj; Zhu, Dongxiao

    2013-02-01

    To mine gene expression data sets effectively, analysis frameworks need to incorporate methods that identify intergenic relationships within enriched biologically relevant subpathways. For this purpose, we developed the Topology Enrichment Analysis frameworK (TEAK). TEAK employs a novel in-house algorithm and a tailor-made Clique Percolation Method to extract linear and nonlinear KEGG subpathways, respectively. TEAK scores subpathways using the Bayesian Information Criterion for context specific data and the Kullback-Leibler divergence for case-control data. In this article, we utilized TEAK with experimental studies to analyze microarray data sets profiling stress responses in the model eukaryote Saccharomyces cerevisiae. Using a public microarray data set, we identified via TEAK linear sphingolipid metabolic subpathways activated during the yeast response to nitrogen stress, and phenotypic analyses of the corresponding deletion strains indicated previously unreported fitness defects for the dpl1Δ and lag1Δ mutants under conditions of nitrogen limitation. In addition, we studied the yeast filamentous response to nitrogen stress by profiling changes in transcript levels upon deletion of two key filamentous growth transcription factors, FLO8 and MSS11. Via TEAK we identified a nonlinear glycerophospholipid metabolism subpathway involving the SLC1 gene, which we found via mutational analysis to be required for yeast filamentous growth. PMID:23268448

  8. Mathematical framework for activity-based cancer biomarkers

    PubMed Central

    Kwong, Gabriel A.; Dudani, Jaideep S.; Carrodeguas, Emmanuel; Mazumdar, Eric V.; Zekavat, Seyedeh M.; Bhatia, Sangeeta N.

    2015-01-01

    Advances in nanomedicine are providing sophisticated functions to precisely control the behavior of nanoscale drugs and diagnostics. Strategies that coopt protease activity as molecular triggers are increasingly important in nanoparticle design, yet the pharmacokinetics of these systems are challenging to understand without a quantitative framework to reveal nonintuitive associations. We describe a multicompartment mathematical model to predict strategies for ultrasensitive detection of cancer using synthetic biomarkers, a class of activity-based probes that amplify cancer-derived signals into urine as a noninvasive diagnostic. Using a model formulation made of a PEG core conjugated with protease-cleavable peptides, we explore a vast design space and identify guidelines for increasing sensitivity that depend on critical parameters such as enzyme kinetics, dosage, and probe stability. According to this model, synthetic biomarkers that circulate in stealth but then activate at sites of disease have the theoretical capacity to discriminate tumors as small as 5 mm in diameter—a threshold sensitivity that is otherwise challenging for medical imaging and blood biomarkers to achieve. This model may be adapted to describe the behavior of additional activity-based approaches to allow cross-platform comparisons, and to predict allometric scaling across species. PMID:26417077

  9. Active-Site-Accessible, Porphyrinic Metal;#8722;Organic Framework Materials

    SciTech Connect

    Farha, Omar K.; Shultz, Abraham M.; Sarjeant, Amy A.; Nguyen, SonBinh T.; Hupp, Joseph T.

    2012-02-06

    On account of their structural similarity to cofactors found in many metallo-enzymes, metalloporphyrins are obvious potential building blocks for catalytically active, metal-organic framework (MOF) materials. While numerous porphyrin-based MOFs have already been described, versions featuring highly accessible active sites and permanent microporosity are remarkably scarce. Indeed, of the more than 70 previously reported porphyrinic MOFs, only one has been shown to be both permanently microporous and contain internally accessible active sites for chemical catalysis. Attempts to generalize the design approach used in this single successful case have failed. Reported here, however, is the synthesis of an extended family of MOFs that directly incorporate a variety of metalloporphyrins (specifically Al{sup 3+}, Zn{sup 2+}, Pd{sup 2+}, Mn{sup 3+}, and Fe{sup 3+} complexes). These robust porphyrinic materials (RPMs) feature large channels and readily accessible active sites. As an illustrative example, one of the manganese-containing RPMs is shown to be catalytically competent for the oxidation of alkenes and alkanes.

  10. Mathematical framework for activity-based cancer biomarkers.

    PubMed

    Kwong, Gabriel A; Dudani, Jaideep S; Carrodeguas, Emmanuel; Mazumdar, Eric V; Zekavat, Seyedeh M; Bhatia, Sangeeta N

    2015-10-13

    Advances in nanomedicine are providing sophisticated functions to precisely control the behavior of nanoscale drugs and diagnostics. Strategies that coopt protease activity as molecular triggers are increasingly important in nanoparticle design, yet the pharmacokinetics of these systems are challenging to understand without a quantitative framework to reveal nonintuitive associations. We describe a multicompartment mathematical model to predict strategies for ultrasensitive detection of cancer using synthetic biomarkers, a class of activity-based probes that amplify cancer-derived signals into urine as a noninvasive diagnostic. Using a model formulation made of a PEG core conjugated with protease-cleavable peptides, we explore a vast design space and identify guidelines for increasing sensitivity that depend on critical parameters such as enzyme kinetics, dosage, and probe stability. According to this model, synthetic biomarkers that circulate in stealth but then activate at sites of disease have the theoretical capacity to discriminate tumors as small as 5 mm in diameter-a threshold sensitivity that is otherwise challenging for medical imaging and blood biomarkers to achieve. This model may be adapted to describe the behavior of additional activity-based approaches to allow cross-platform comparisons, and to predict allometric scaling across species. PMID:26417077

  11. NL(q) Theory: A Neural Control Framework with Global Asymptotic Stability Criteria.

    PubMed

    Vandewalle, Joos; De Moor, Bart L.R.; Suykens, Johan A.K.

    1997-06-01

    In this paper a framework for model-based neural control design is presented, consisting of nonlinear state space models and controllers, parametrized by multilayer feedforward neural networks. The models and closed-loop systems are transformed into so-called NL(q) system form. NL(q) systems represent a large class of nonlinear dynamical systems consisting of q layers with alternating linear and static nonlinear operators that satisfy a sector condition. For such NL(q)s sufficient conditions for global asymptotic stability, input/output stability (dissipativity with finite L(2)-gain) and robust stability and performance are presented. The stability criteria are expressed as linear matrix inequalities. In the analysis problem it is shown how stability of a given controller can be checked. In the synthesis problem two methods for neural control design are discussed. In the first method Narendra's dynamic backpropagation for tracking on a set of specific reference inputs is modified with an NL(q) stability constraint in order to ensure, e.g., closed-loop stability. In a second method control design is done without tracking on specific reference inputs, but based on the input/output stability criteria itself, within a standard plant framework as this is done, for example, in H( infinity ) control theory and &mgr; theory. Copyright 1997 Elsevier Science Ltd. PMID:12662859

  12. Theory of Planned Behavior in School-Based Adolescent Problem Gambling Prevention: A Conceptual Framework.

    PubMed

    St-Pierre, Renée A; Temcheff, Caroline E; Derevensky, Jeffrey L; Gupta, Rina

    2015-12-01

    Given its serious implications for psychological and socio-emotional health, the prevention of problem gambling among adolescents is increasingly acknowledged as an area requiring attention. The theory of planned behavior (TPB) is a well-established model of behavior change that has been studied in the development and evaluation of primary preventive interventions aimed at modifying cognitions and behavior. However, the utility of the TPB has yet to be explored as a framework for the development of adolescent problem gambling prevention initiatives. This paper first examines the existing empirical literature addressing the effectiveness of school-based primary prevention programs for adolescent gambling. Given the limitations of existing programs, we then present a conceptual framework for the integration of the TPB in the development of effective problem gambling preventive interventions. The paper describes the TPB, demonstrates how the framework has been applied to gambling behavior, and reviews the strengths and limitations of the model for the design of primary prevention initiatives targeting adolescent risk and addictive behaviors, including adolescent gambling. PMID:26480847

  13. Self-Determination Theory in Schools of Education: Can an Empirically Supported Framework also Be Critical and Liberating?

    ERIC Educational Resources Information Center

    Ryan, Richard M.; Niemiec, Christopher P.

    2009-01-01

    In many graduate schools of education there is strong resistance to formal theories, especially those that are supported through quantitative empirical methods. In this article we describe how self-determination theory (SDT), a formal and empirically focused framework, shares sensibilities with critical theorists concerning the importance of…

  14. Building a framework for theory-based ethnographies for studying intergenerational family food practices.

    PubMed

    Visser, Sanne Siete; Hutter, Inge; Haisma, Hinke

    2016-02-01

    The growing rates of (childhood) obesity worldwide are a source concern for health professionals, policy-makers, and researchers. The increasing prevalence of associated diseases-such as diabetes, cardiovascular diseases, and psychological problems-shows the impact of obesity on people's health, already from a young age. In turn, these problems have obvious consequences for the health care system, including higher costs. However, the treatment of obesity has proven to be difficult, which makes prevention an important goal. In this study, we focus on food practices, one of the determinants of obesity. In recent years, it has become increasingly clear that interventions designed to encourage healthy eating of children and their families are not having the desired impact, especially among groups with a lower socioeconomic background (SEB). To understand why interventions fail to have an impact, we need to study the embedded social and cultural constructions of families. We argue that we need more than just decision-making theories to understand this cultural embeddedness, and to determine what cultural and social factors influence the decision-making process. By allowing families to explain their cultural background, their capabilities, and their opportunities, we will gain new insights into how families choose what they eat from a complex set of food choices. We have thus chosen to build a framework based on Sen's capability approach and the theory of cultural schemas. This framework, together with a holistic ethnographic research approach, can help us better understand what drives the food choices made in families. The framework is built to serve as a starting point for ethnographic research on food choice in families, and could contribute to the development of interventions that are embedded in the cultural realities of the targeted groups. PMID:26593100

  15. A Phenomenological Study of an Emergent National Digital Library, Part I: Theory and Methodological Framework

    ERIC Educational Resources Information Center

    Dalbello, Marija

    2005-01-01

    The activities surrounding the National Digital Library Program (NDLP) at the Library of Congress (1995-2000) are used to study institutional processes associated with technological innovation in the library context. The study identified modalities of successful innovation and the characteristics of creative decision making. Theories of social…

  16. Brain activity and cognition: a connection from thermodynamics and information theory

    PubMed Central

    Collell, Guillem; Fauquet, Jordi

    2015-01-01

    The connection between brain and mind is an important scientific and philosophical question that we are still far from completely understanding. A crucial point to our work is noticing that thermodynamics provides a convenient framework to model brain activity, whereas cognition can be modeled in information-theoretical terms. In fact, several models have been proposed so far from both approaches. A second critical remark is the existence of deep theoretical connections between thermodynamics and information theory. In fact, some well-known authors claim that the laws of thermodynamics are nothing but principles in information theory. Unlike in physics or chemistry, a formalization of the relationship between information and energy is currently lacking in neuroscience. In this paper we propose a framework to connect physical brain and cognitive models by means of the theoretical connections between information theory and thermodynamics. Ultimately, this article aims at providing further insight on the formal relationship between cognition and neural activity. PMID:26136709

  17. Brain activity and cognition: a connection from thermodynamics and information theory.

    PubMed

    Collell, Guillem; Fauquet, Jordi

    2015-01-01

    The connection between brain and mind is an important scientific and philosophical question that we are still far from completely understanding. A crucial point to our work is noticing that thermodynamics provides a convenient framework to model brain activity, whereas cognition can be modeled in information-theoretical terms. In fact, several models have been proposed so far from both approaches. A second critical remark is the existence of deep theoretical connections between thermodynamics and information theory. In fact, some well-known authors claim that the laws of thermodynamics are nothing but principles in information theory. Unlike in physics or chemistry, a formalization of the relationship between information and energy is currently lacking in neuroscience. In this paper we propose a framework to connect physical brain and cognitive models by means of the theoretical connections between information theory and thermodynamics. Ultimately, this article aims at providing further insight on the formal relationship between cognition and neural activity. PMID:26136709

  18. The activation strain model and molecular orbital theory

    PubMed Central

    Wolters, Lando P; Bickelhaupt, F Matthias

    2015-01-01

    The activation strain model is a powerful tool for understanding reactivity, or inertness, of molecular species. This is done by relating the relative energy of a molecular complex along the reaction energy profile to the structural rigidity of the reactants and the strength of their mutual interactions: ΔE(ζ) = ΔEstrain(ζ) + ΔEint(ζ). We provide a detailed discussion of the model, and elaborate on its strong connection with molecular orbital theory. Using these approaches, a causal relationship is revealed between the properties of the reactants and their reactivity, e.g., reaction barriers and plausible reaction mechanisms. This methodology may reveal intriguing parallels between completely different types of chemical transformations. Thus, the activation strain model constitutes a unifying framework that furthers the development of cross-disciplinary concepts throughout various fields of chemistry. We illustrate the activation strain model in action with selected examples from literature. These examples demonstrate how the methodology is applied to different research questions, how results are interpreted, and how insights into one chemical phenomenon can lead to an improved understanding of another, seemingly completely different chemical process. WIREs Comput Mol Sci 2015, 5:324–343. doi: 10.1002/wcms.1221 PMID:26753009

  19. Resilience and vulnerability to a natural hazard: A mathematical framework based on viability theory

    NASA Astrophysics Data System (ADS)

    Rougé, Charles; Mathias, Jean-Denis; Deffuant, Guillaume

    2013-04-01

    This deals with the response of a coupled human and natural system (CHANS) to a natural hazard by using the concepts of resilience and vulnerability within the mathematical framework of viability theory. This theory applies to time-evolving systems such as CHANS and assumes that their desirable properties can be defined as a subset of their state space. Policies can also apply to influence the dynamics of such systems: viability theory aims at finding the policies which keep the properties of a controlled dynamical system for so long as no disturbance hits it. The states of the system such that the properties are guaranteed constitute what is called the viability kernel. This viability framework has been extended to describe the response to a perturbation such as a natural hazard. Resilience describes the capacity of the CHANS to recover by getting back in the viability kernel, where its properties are guaranteed until the onset of the next major event. Defined for a given controlled trajectory that the system may take after the event ends, resilience is (a) whether the system comes back to the viability kernel within a given budget such as a time constraint, but also (b) a decreasing function of vulnerability. Computed for a given trajectory as well, vulnerability is a measure of the consequence of violating a property. We propose a family of functions from which cost functions and other vulnerability indicators can be derived for a certain trajectory. There can be several vulnerability functions, representing for instance social, economic or ecological vulnerability, and each representing the violation of an associated property, but these functions need to be ultimately aggregated as a single indicator. Computing the resilience and vulnerability of a trajectory enables the viability framework to describe the response of both deterministic and stochastic systems to hazards. In the deterministic case, there is only one response trajectory for a given action policy

  20. Frameworks.

    ERIC Educational Resources Information Center

    Olson, Mary Ann, Ed.; Baer, Teddi, Ed.

    1984-01-01

    Intended for writing teachers, the activities in this issue blend right/left brain lessons--kinesthetic, spatial, and playful--to provide students with prewriting experience. The activities include the following: (1) creativity olympics, such as finding criteria by which large groups of students may subdivide themselves into successively smaller…

  1. Activity Theory and Higher Education: Evaluating Learning Technologies

    ERIC Educational Resources Information Center

    Scanlon, E.; Issroff, K.

    2005-01-01

    This paper examines current practice in the evaluation of learning technology in the UK and proposes a new approach informed by Activity Theory. It is based on our experiences of using Activity Theory to understand students' and lecturers' experiences of technology-based teaching environments. We discuss the activity of evaluating learning…

  2. Unpacking teacher-researcher collaboration with three theoretical frameworks: a case of expansive learning activity?

    NASA Astrophysics Data System (ADS)

    Gade, Sharada

    2015-09-01

    Long association with a mathematics teacher at a Grade 4-6 school in Sweden, is basis for reporting a case of teacher-researcher collaboration. Three theoretical frameworks used to study its development over time are relational knowing, relational agency and cogenerative dialogue. While relational knowing uses narrative perspectives to explore the experiential and relational nature of collaboration; relational agency, draws on activity theory perspectives and identifies the change in the purpose of collaboration, from initially conducting classroom interventions to co-authoring research. Finally, cogenerative dialogue, deploys hermeneutic-phenomenological perspectives and investigates the dialogue that transpired between Lotta and the author, as they co-authored their research report. Such analysis sheds invaluable light on a case of expansive learning activity.

  3. Stationary waves on nonlinear quantum graphs: General framework and canonical perturbation theory

    NASA Astrophysics Data System (ADS)

    Gnutzmann, Sven; Waltner, Daniel

    2016-03-01

    In this paper we present a general framework for solving the stationary nonlinear Schrödinger equation (NLSE) on a network of one-dimensional wires modeled by a metric graph with suitable matching conditions at the vertices. A formal solution is given that expresses the wave function and its derivative at one end of an edge (wire) nonlinearly in terms of the values at the other end. For the cubic NLSE this nonlinear transfer operation can be expressed explicitly in terms of Jacobi elliptic functions. Its application reduces the problem of solving the corresponding set of coupled ordinary nonlinear differential equations to a finite set of nonlinear algebraic equations. For sufficiently small amplitudes we use canonical perturbation theory, which makes it possible to extract the leading nonlinear corrections over large distances.

  4. Stationary waves on nonlinear quantum graphs: General framework and canonical perturbation theory.

    PubMed

    Gnutzmann, Sven; Waltner, Daniel

    2016-03-01

    In this paper we present a general framework for solving the stationary nonlinear Schrödinger equation (NLSE) on a network of one-dimensional wires modeled by a metric graph with suitable matching conditions at the vertices. A formal solution is given that expresses the wave function and its derivative at one end of an edge (wire) nonlinearly in terms of the values at the other end. For the cubic NLSE this nonlinear transfer operation can be expressed explicitly in terms of Jacobi elliptic functions. Its application reduces the problem of solving the corresponding set of coupled ordinary nonlinear differential equations to a finite set of nonlinear algebraic equations. For sufficiently small amplitudes we use canonical perturbation theory, which makes it possible to extract the leading nonlinear corrections over large distances. PMID:27078341

  5. The theory of event coding (TEC) as embodied-cognition framework

    PubMed Central

    Hommel, Bernhard

    2015-01-01

    The concept of embodied cognition attracts enormous interest but neither is the concept particularly well-defined nor is the related research guided by systematic theorizing. To improve this situation the theory of event coding (TEC) is suggested as a suitable theoretical framework for theorizing about cognitive embodiment—which, however, presupposes giving up the anti-cognitivistic attitude inherent in many embodiment approaches. The article discusses the embodiment-related potential of TEC, and the way and degree to which it addresses Wilson’s (2002) six meanings of the embodiment concept. In particular, it is discussed how TEC considers human cognition to be situated, distributed, and body-based, how it deals with time pressure, how it delegates work to the environment, and in which sense it subserves action. PMID:26388819

  6. Characterize Framework for Igneous Activity at Yucca Mountain, Nevada

    SciTech Connect

    F. Perry; B. Youngs

    2000-11-06

    The purpose of this Analysis/Model (AMR) report is twofold. (1) The first is to present a conceptual framework of igneous activity in the Yucca Mountain region (YMR) consistent with the volcanic and tectonic history of this region and the assessment of this history by experts who participated in the Probabilistic Volcanic Hazard Analysis (PVHA) (CRWMS M&O 1996). Conceptual models presented in the PVHA are summarized and extended in areas in which new information has been presented. Alternative conceptual models are discussed as well as their impact on probability models. The relationship between volcanic source zones defined in the PVHA and structural features of the YMR are described based on discussions in the PVHA and studies presented since the PVHA. (2) The second purpose of the AMR is to present probability calculations based on PVHA outputs. Probability distributions are presented for the length and orientation of volcanic dikes within the repository footprint and for the number of eruptive centers located within the repository footprint (conditional on the dike intersecting the repository). The probability of intersection of a basaltic dike within the repository footprint was calculated in the AMR ''Characterize Framework for Igneous Activity at Yucca Mountain, Nevada'' (CRWMS M&O 2000g) based on the repository footprint known as the Enhanced Design Alternative [EDA II, Design B (CRWMS M&O 1999a; Wilkins and Heath 1999)]. Then, the ''Site Recommendation Design Baseline'' (CRWMS M&O 2000a) initiated a change in the repository design, which is described in the ''Site Recommendation Subsurface Layout'' (CRWMS M&O 2000b). Consequently, the probability of intersection of a basaltic dike within the repository footprint has also been calculated for the current repository footprint, which is called the 70,000 Metric Tons of Uranium (MTU) No-Backfill Layout (CRWMS M&O 2000b). The calculations for both footprints are presented in this AMR. In addition, the

  7. Geodesic active fields--a geometric framework for image registration.

    PubMed

    Zosso, Dominique; Bresson, Xavier; Thiran, Jean-Philippe

    2011-05-01

    In this paper we present a novel geometric framework called geodesic active fields for general image registration. In image registration, one looks for the underlying deformation field that best maps one image onto another. This is a classic ill-posed inverse problem, which is usually solved by adding a regularization term. Here, we propose a multiplicative coupling between the registration term and the regularization term, which turns out to be equivalent to embed the deformation field in a weighted minimal surface problem. Then, the deformation field is driven by a minimization flow toward a harmonic map corresponding to the solution of the registration problem. This proposed approach for registration shares close similarities with the well-known geodesic active contours model in image segmentation, where the segmentation term (the edge detector function) is coupled with the regularization term (the length functional) via multiplication as well. As a matter of fact, our proposed geometric model is actually the exact mathematical generalization to vector fields of the weighted length problem for curves and surfaces introduced by Caselles-Kimmel-Sapiro. The energy of the deformation field is measured with the Polyakov energy weighted by a suitable image distance, borrowed from standard registration models. We investigate three different weighting functions, the squared error and the approximated absolute error for monomodal images, and the local joint entropy for multimodal images. As compared to specialized state-of-the-art methods tailored for specific applications, our geometric framework involves important contributions. Firstly, our general formulation for registration works on any parametrizable, smooth and differentiable surface, including nonflat and multiscale images. In the latter case, multiscale images are registered at all scales simultaneously, and the relations between space and scale are intrinsically being accounted for. Second, this method is, to

  8. The path dependency theory: analytical framework to study institutional integration. The case of France

    PubMed Central

    Trouvé, Hélène; Couturier, Yves; Etheridge, Francis; Saint-Jean, Olivier; Somme, Dominique

    2010-01-01

    Background The literature on integration indicates the need for an enhanced theorization of institutional integration. This article proposes path dependence as an analytical framework to study the systems in which integration takes place. Purpose PRISMA proposes a model for integrating health and social care services for older adults. This model was initially tested in Quebec. The PRISMA France study gave us an opportunity to analyze institutional integration in France. Methods A qualitative approach was used. Analyses were based on semi-structured interviews with actors of all levels of decision-making, observations of advisory board meetings, and administrative documents. Results Our analyses revealed the complexity and fragmentation of institutional integration. The path dependency theory, which analyzes the change capacity of institutions by taking into account their historic structures, allows analysis of this situation. The path dependency to the Bismarckian system and the incomplete reforms of gerontological policies generate the coexistence and juxtaposition of institutional systems. In such a context, no institution has sufficient ability to determine gerontology policy and build institutional integration by itself. Conclusion Using path dependence as an analytical framework helps to understand the reasons why institutional integration is critical to organizational and clinical integration, and the complex construction of institutional integration in France. PMID:20689740

  9. Activity Theory and Situated Learning Theory: Contrasting Views of Educational Practice

    ERIC Educational Resources Information Center

    Arnseth, Hans Christian

    2008-01-01

    The purpose of this article is to offer a critical discussion of the practice turn in contemporary educational research. In order to make the discussion specific, I use two influential theories, namely activity theory and situated learning theory. They both turn to the notion of practice in order to overcome the limitations of mentalist and…

  10. Normalisation process theory: a framework for developing, evaluating and implementing complex interventions

    PubMed Central

    2010-01-01

    Background The past decade has seen considerable interest in the development and evaluation of complex interventions to improve health. Such interventions can only have a significant impact on health and health care if they are shown to be effective when tested, are capable of being widely implemented and can be normalised into routine practice. To date, there is still a problematic gap between research and implementation. The Normalisation Process Theory (NPT) addresses the factors needed for successful implementation and integration of interventions into routine work (normalisation). Discussion In this paper, we suggest that the NPT can act as a sensitising tool, enabling researchers to think through issues of implementation while designing a complex intervention and its evaluation. The need to ensure trial procedures that are feasible and compatible with clinical practice is not limited to trials of complex interventions, and NPT may improve trial design by highlighting potential problems with recruitment or data collection, as well as ensuring the intervention has good implementation potential. Summary The NPT is a new theory which offers trialists a consistent framework that can be used to describe, assess and enhance implementation potential. We encourage trialists to consider using it in their next trial. PMID:20961442

  11. Social simulation theory: a framework to explain nurses' understanding of patients' experiences of ill-health.

    PubMed

    Nordby, Halvor

    2016-09-01

    A fundamental aim in caring practice is to understand patients' experiences of ill-health. These experiences have a qualitative content and cannot, unlike thoughts and beliefs with conceptual content, directly be expressed in words. Nurses therefore face a variety of interpretive challenges when they aim to understand patients' subjective perspectives on disease and illness. The article argues that theories on social simulation can shed light on how nurses manage to meet these challenges. The core assumption of social simulationism is that we do not understand other people by forming mental representations of how they think, but by putting ourselves in their situation in a more imaginative way. According to simulationism, any attempt to understand a patient's behavior is made on the basis of simulating what it is like to be that patient in the given context. The article argues that this approach to social interpretation can clarify how nurses manage to achieve aims of patient understanding, even when they have limited time to communicate and incomplete knowledge of patients' perspectives. Furthermore, simulation theory provides a normative framework for interpretation, in the sense that its theoretical assumptions constitute ideals for how nurses should seek to understand patients' experiences of illness. PMID:27198752

  12. A graph-theory framework for evaluating landscape connectivity and conservation planning.

    PubMed

    Minor, Emily S; Urban, Dean L

    2008-04-01

    Connectivity of habitat patches is thought to be important for movement of genes, individuals, populations, and species over multiple temporal and spatial scales. We used graph theory to characterize multiple aspects of landscape connectivity in a habitat network in the North Carolina Piedmont (U.S.A). We compared this landscape with simulated networks with known topology, resistance to disturbance, and rate of movement. We introduced graph measures such as compartmentalization and clustering, which can be used to identify locations on the landscape that may be especially resilient to human development or areas that may be most suitable for conservation. Our analyses indicated that for songbirds the Piedmont habitat network was well connected. Furthermore, the habitat network had commonalities with planar networks, which exhibit slow movement, and scale-free networks, which are resistant to random disturbances. These results suggest that connectivity in the habitat network was high enough to prevent the negative consequences of isolation but not so high as to allow rapid spread of disease. Our graph-theory framework provided insight into regional and emergent global network properties in an intuitive and visual way and allowed us to make inferences about rates and paths of species movements and vulnerability to disturbance. This approach can be applied easily to assessing habitat connectivity in any fragmented or patchy landscape. PMID:18241238

  13. Phenomenology of stabilizing moduli in a framework of gx meson compactification of M-theory

    NASA Astrophysics Data System (ADS)

    Shao, Jing

    This thesis explores an interesting class of fluxless G 2 compactifications of M-theory, where all the moduli are stabilized and a TeV scale is generated with the Planck scale as the only dimensionful input. A well-motivated phenomenological model---the G 2-MSSM, can be naturally defined within this framework. In this thesis, important phenomenological aspects of the G2-MSSM are carefully studied. First, the soft supersymmetry breaking parameters and the superpartner mass spectrum are computed. The spectrum is found to contain light gauginos and heavy scalars with a wino LSP when the vacuum energy is tuned to be small. The prospects for discovery at the Large Hadron Collider (LHC) are promising. The model predicts a spectacular four-top signature, which can be easily identified at the LHC. In addition, the charginos are meta-stable and could be detected directly at the LHC providing additional information about the nature of the LSP. Second, in the G 2-MSSM CP-violating phases occur in the quark and lepton Yukawas but are not generated from the supersymmetry breaking. However, in such models additional CP violation can be generated because the soft trilinear matrices are not proportional to the Yukawa matrices. The estimated upper bounds for the electric dipole moments of the electron, neutron and mercury are all within the current experimental limits and could be probed in the near future. Finally, the cosmological moduli/gravitino problems and the issue of too little thermal but excessive non-thermal dark matter from the decays of moduli are studied. It is shown that the late decaying moduli not only satisfy the Big Bang Nucleosynthesis constraints but also avoid the gravitino problem. The non-thermal production of wino LSPs gives a right amount of relic density. The phenomenological results obtained in this thesis can be tested by coming experiments, particularly the LHC experiments, and therefore provide a means to connect the experimental data to a high scale

  14. The importance of behavior theory in control system modeling of physical activity sensor data.

    PubMed

    Riley, William T; Martin, Cesar A; Rivera, Daniel E

    2014-01-01

    Among health behaviors, physical activity has the most extensive record of research using passive sensors. Control systems and other system dynamic approaches have long been considered applicable for understanding human behavior, but only recently has the technology provided the precise and intensive longitudinal data required for these analytic approaches. Although sensors provide intensive data on the patterns and variations of physical activity over time, the influences of these variations are often unmeasured. Health behavior theories provide an explanatory framework of the putative mediators of physical activity changes. Incorporating the intensive longitudinal measurement of these theoretical constructs is critical to improving the fit of control system model of physical activity and for advancing behavioral theory. Theory-based control models also provide guidance on the nature of the controllers which serve as the basis for just-in-time adaptive interventions based on these control system models. PMID:25571577

  15. Community Service-Learning and Cultural-Historical Activity Theory

    ERIC Educational Resources Information Center

    Taylor, Alison

    2014-01-01

    This paper explores the potential of cultural-historical activity theory (CHAT), to provide new insights into community service-learning (CSL) in higher education. While CSL literature acknowledges the influences of John Dewey and Paolo Freire, discussion of the potential contribution of cultural-historical activity theory, rooted in the work of…

  16. A Guided Inquiry Activity for Teaching Ligand Field Theory

    ERIC Educational Resources Information Center

    Johnson, Brian J.; Graham, Kate J.

    2015-01-01

    This paper will describe a guided inquiry activity for teaching ligand field theory. Previous research suggests the guided inquiry approach is highly effective for student learning. This activity familiarizes students with the key concepts of molecular orbital theory applied to coordination complexes. Students will learn to identify factors that…

  17. Teaching Sociological Theory through Active Learning: The Irrigation Exercise

    ERIC Educational Resources Information Center

    Holtzman, Mellisa

    2005-01-01

    For students, theory is often one of the most daunting aspects of sociology--it seems abstract, removed from the concrete events of their everyday lives, and therefore intimidating. In an attempt to break down student resistance to theory, instructors are increasingly turning to active learning approaches. Active learning exercises, then, appear…

  18. A Systematic Review Exploring the Social Cognitive Theory of Self-Regulation as a Framework for Chronic Health Condition Interventions

    PubMed Central

    Tougas, Michelle E.; Hayden, Jill A.; McGrath, Patrick J.; Huguet, Anna; Rozario, Sharlene

    2015-01-01

    Background Theory is often recommended as a framework for guiding hypothesized mechanisms of treatment effect. However, there is limited guidance about how to use theory in intervention development. Methods We conducted a systematic review to provide an exemplar review evaluating the extent to which use of theory is identified and incorporated within existing interventions. We searched electronic databases PubMed, PsycINFO, CENTRAL, and EMBASE from inception to May 2014. We searched clinicaltrials.gov for registered protocols, reference lists of relevant systematic reviews and included studies, and conducted a citation search in Web of Science. We included peer-reviewed publications of interventions that referenced the social cognitive theory of self-regulation as a framework for interventions to manage chronic health conditions. Two reviewers independently assessed articles for eligibility. We contacted all authors of included studies for information detailing intervention content. We describe how often theory mechanisms were addressed by interventions, and report intervention characteristics used to address theory. Results Of 202 articles that reported using the social cognitive theory of self-regulation, 52% failed to incorporate self-monitoring, a main theory component, and were therefore excluded. We included 35 interventions that adequately used the theory framework. Intervention characteristics were often poorly reported in peer-reviewed publications, 21 of 35 interventions incorporated characteristics that addressed each of the main theory components. Each intervention addressed, on average, six of eight self-monitoring mechanisms, two of five self-judgement mechanisms, and one of three self-evaluation mechanisms. The self-monitoring mechanisms ‘Feedback’ and ‘Consistency’ were addressed by all interventions, whereas the self-evaluation mechanisms ‘Self-incentives’ and ‘External rewards’ were addressed by six and four interventions

  19. Characterize Framework for Igneous Activity at Yucca Mountain, Nevada

    SciTech Connect

    F. Perry; R. Youngs

    2004-10-14

    The purpose of this scientific analysis report is threefold: (1) Present a conceptual framework of igneous activity in the Yucca Mountain region (YMR) consistent with the volcanic and tectonic history of this region and the assessment of this history by experts who participated in the probabilistic volcanic hazard analysis (PVHA) (CRWMS M&O 1996 [DIRS 100116]). Conceptual models presented in the PVHA are summarized and applied in areas in which new information has been presented. Alternative conceptual models are discussed, as well as their impact on probability models. The relationship between volcanic source zones defined in the PVHA and structural features of the YMR are described based on discussions in the PVHA and studies presented since the PVHA. (2) Present revised probability calculations based on PVHA outputs for a repository footprint proposed in 2003 (BSC 2003 [DIRS 162289]), rather than the footprint used at the time of the PVHA. This analysis report also calculates the probability of an eruptive center(s) forming within the repository footprint using information developed in the PVHA. Probability distributions are presented for the length and orientation of volcanic dikes located within the repository footprint and for the number of eruptive centers (conditional on a dike intersecting the repository) located within the repository footprint. (3) Document sensitivity studies that analyze how the presence of potentially buried basaltic volcanoes may affect the computed frequency of intersection of the repository footprint by a basaltic dike. These sensitivity studies are prompted by aeromagnetic data collected in 1999, indicating the possible presence of previously unrecognized buried volcanoes in the YMR (Blakely et al. 2000 [DIRS 151881]; O'Leary et al. 2002 [DIRS 158468]). The results of the sensitivity studies are for informational purposes only and are not to be used for purposes of assessing repository performance.

  20. The Work Compatibility Improvement Framework: theory and application of improvement action and intervention strategies.

    PubMed

    Genaidy, Ash M; Rinder, Magda M; Sequeira, Reynold; A-Rehim, Amal D

    2009-05-01

    Challenges facing management of manufacturing firms can be transformed into asset gains by giving careful consideration to the worker-work environment interface. The benefits of a 'healthy' interface may lead to sizable reductions in rising health care costs and retention of highly qualified workers. This paper presents a novel approach for the 'improve' phase of the Work Compatibility Improvement Framework. The work tasks of this research consisted of: (a) fundamentals of cognitive-based improvement action and intervention; (b) design concepts and process of improvement action/intervention generation; (c) assessment model of estimated gains in company's assets; (d) application demonstration in the manufacturing sector. The process of improvement action/intervention generation is described, preceded by a description of the fundamentals of cognitive-based improvement action and intervention and system architecture. This is followed by a documentation of estimated asset gains as a result of the improvement plan. The results showed that expert workers were, on average, 78% in agreement with the algorithm-identified improvement actions. Their knowledge was used to update the recommended actions as well as to detail the multiple strategies required to address the improvement actions. As a result, an integrated improvement plan was developed resulting in estimated asset gains of $1.6 million, which was validated by the general manager. The research reported herein documented the theory and application of the 'improve' phase of the Work Compatibility Improvement Framework. The economic assessment of the suggested improvement is also reported and this has proved to be an important driver to secure the firm collaboration of manufacturing enterprise management. An integrated improvement solution plan backed by a detailed economic assessment of suggested improvements is essential to demonstrate the full potential of workplace micro- and macro-ergonomic interventions. PMID

  1. Critical Curriculum Theory and Slow Ecopedagogical Activism

    ERIC Educational Resources Information Center

    Payne, Phillip G.

    2015-01-01

    Enacting a critical environmental education curriculum theory with 8- to 9-year-old children in 1978 is now "restoried" in a "history of the present/future" like "case study" for prosecuting five interrelated problems confronting progress in environmental education and its research. They are: the intense heat of the…

  2. Protopopov's ideas on habit formation and their relation to the Pavlovian theory of higher nervous activity.

    PubMed

    Windholz, G

    1999-01-01

    In 1929 Viktor P. Protopopov began to replicate E. L. Thorndike's animal experiments on habit acquisition. To determine the conditions necessary for habit formation, Protopopov used the natural experiment method, in which dogs encountered environments that prevented them from reaching a stimulus-bait. Not all dogs acquired the behavior necessary for obtaining the bait. Explaining the results within the framework of the Pavlovian theory of higher nervous activity, Protopopov concluded that habits were acquired when an active animal provoked by a bait-stimulus encountered an environmental barrier. The dogs tried a series of phylogenetic behaviors until the stimulus-bait was reached. The latter movements were retained, forming an ontogenetic habit. The dogs also learned not to produce the unsuccessful movements. In accord with the Pavlovian theory, individual differences in habit formation were related to temperament types. A critique of the Thorndikian Law of Effect is provided in terms of the Pavlovian theory of higher nervous activity. PMID:10696273

  3. Factors Influencing the Selection of Speech Pathology as a Career: A Qualitative Analysis Utilising the Systems Theory Framework

    ERIC Educational Resources Information Center

    Byrne, Nicole

    2007-01-01

    Factors identified by 16 participants during in-depth interviews as influencing selection of speech pathology as a career were described using the Systems Theory Framework (STF, Patton & McMahon, 2006). Participants were highly likely to identify factors from the individual and social systems, but not the environmental-societal system, of the STF…

  4. Problems with McAdams and Pals's (2006) Proposal of a Framework for an Integrative Theory of Personality

    ERIC Educational Resources Information Center

    Epstein, Seymour

    2007-01-01

    Comments on the original article "A New Big Five: Fundamental Principles for an Integrative Science of Personality," by Dan P. McAdams and Jennifer L. Pals (see record 2006-03947-002). Here, the current author begins with a critique of McAdams and Pals's (April 2006) five principles for a framework for an integrative theory of personality. The…

  5. Optimisation of simulated team training through the application of learning theories: a debate for a conceptual framework

    PubMed Central

    2014-01-01

    Background As a conceptual review, this paper will debate relevant learning theories to inform the development, design and delivery of an effective educational programme for simulated team training relevant to health professionals. Discussion Kolb’s experiential learning theory is used as the main conceptual framework to define the sequence of activities. Dewey’s theory of reflective thought and action, Jarvis modification of Kolb’s learning cycle and Schön’s reflection-on-action serve as a model to design scenarios for optimal concrete experience and debriefing for challenging participants’ beliefs and habits. Bandura’s theory of self-efficacy and newer socio-cultural learning models outline that for efficient team training, it is mandatory to introduce the social-cultural context of a team. Summary The ideal simulated team training programme needs a scenario for concrete experience, followed by a debriefing with a critical reflexive observation and abstract conceptualisation phase, and ending with a second scenario for active experimentation. Let them re-experiment to optimise the effect of a simulated training session. Challenge them to the edge: The scenario needs to challenge participants to generate failures and feelings of inadequacy to drive and motivate team members to critical reflect and learn. Not experience itself but the inadequacy and contradictions of habitual experience serve as basis for reflection. Facilitate critical reflection: Facilitators and group members must guide and motivate individual participants through the debriefing session, inciting and empowering learners to challenge their own beliefs and habits. To do this, learners need to feel psychological safe. Let the group talk and critical explore. Motivate with reality and context: Training with multidisciplinary team members, with different levels of expertise, acting in their usual environment (in-situ simulation) on physiological variables is mandatory to introduce

  6. The Link Between ADHD and the Risk of Sexual Victimization Among College Women: Expanding the Lifestyles/Routine Activities Framework.

    PubMed

    Snyder, Jamie A

    2015-11-01

    Using data from a nationally representative sample of college women, the current study examines attention deficit hyperactivity disorder (ADHD) as a potential risk factor in the prediction of sexual victimization among college women and as an extension of the lifestyles/routine activities framework. The findings indicate that college women with ADHD experienced sexual victimization at significantly higher rates than college women without ADHD. Furthermore, ADHD emerged as a significant predictor of sexual victimization across models. The lifestyles/routine activities theory also received general support, particularly for the concepts of exposure, proximity, and guardianship. This research suggests that other risk factors outside the lifestyles/routine activities framework are important in the prediction of sexual victimization in college women. PMID:26155795

  7. Testing Social Cognitive Theory as a theoretical framework to predict smoking relapse among daily smoking adolescents.

    PubMed

    Van Zundert, Rinka M P; Nijhof, Linda M; Engels, Rutger C M E

    2009-03-01

    Predictors of adolescent smoking relapse are largely unknown, since studies either focus on relapse among adults, or address (long-term) smoking cessation but not relapse. In the present study, Social Cognitive Theory (SCT) was used as a theoretical framework to examine the first and second lapses, as well as mild and heavy relapse into smoking among 135 daily smoking adolescents who embarked on a serious quit attempt. Baseline predictors were pros of smoking, pros of quitting, self-efficacy, and intensity of smoking. Using an ecological momentary assessment (EMA) study design, participants were monitored three times a day during 4 weeks. A follow-up was administered 2 months after the monitoring period. Perceiving many pros of smoking, reporting a low self-efficacy to quit, and high levels of baseline smoking significantly predicted relapse within 3 weeks after quitting. The effects of pros of smoking and self-efficacy on relapse, however, appeared to be accounted for by differences in intensity of smoking. Besides that pros of quitting showed a marginal effect on abstinence at the 2-month follow-up, no long-term effects were detected. PMID:19059732

  8. Studying Activities That Take Place in Speech Interactions: A Theoretical and Methodological Framework

    ERIC Educational Resources Information Center

    Saint-Dizier de Almeida, Valérie; Colletta, Jean-Marc; Auriac-Slusarczyk, Emmanuelle; Specogna, Antonietta; Simon, Jean-Pascal; Fiema, Gabriela; Luxembourger, Christophe

    2016-01-01

    The paper proposes a theoretical and methodological framework based on a pluralistic, concerted approach to the study of activities that take place in and through speech interactions. The framework has a general scope, applying to any collective activity taking form through language interactions. It contributes to a fuller understanding of the…

  9. A Theory of Information Quality and a Framework for its Implementation in the Requirements Engineering Process

    NASA Astrophysics Data System (ADS)

    Grenn, Michael W.

    This dissertation introduces a theory of information quality to explain macroscopic behavior observed in the systems engineering process. The theory extends principles of Shannon's mathematical theory of communication [1948] and statistical mechanics to information development processes concerned with the flow, transformation, and meaning of information. The meaning of requirements information in the systems engineering context is estimated or measured in terms of the cumulative requirements quality Q which corresponds to the distribution of the requirements among the available quality levels. The requirements entropy framework (REF) implements the theory to address the requirements engineering problem. The REF defines the relationship between requirements changes, requirements volatility, requirements quality, requirements entropy and uncertainty, and engineering effort. The REF is evaluated via simulation experiments to assess its practical utility as a new method for measuring, monitoring and predicting requirements trends and engineering effort at any given time in the process. The REF treats the requirements engineering process as an open system in which the requirements are discrete information entities that transition from initial states of high entropy, disorder and uncertainty toward the desired state of minimum entropy as engineering effort is input and requirements increase in quality. The distribution of the total number of requirements R among the N discrete quality levels is determined by the number of defined quality attributes accumulated by R at any given time. Quantum statistics are used to estimate the number of possibilities P for arranging R among the available quality levels. The requirements entropy H R is estimated using R, N and P by extending principles of information theory and statistical mechanics to the requirements engineering process. The information I increases as HR and uncertainty decrease, and the change in information AI needed

  10. Object relations theory and activity theory: a proposed link by way of the procedural sequence model.

    PubMed

    Ryle, A

    1991-12-01

    An account of object relations theory (ORT), represented in terms of the procedural sequence model (PSM), is compared to the ideas of Vygotsky and activity theory (AT). The two models are seen to be compatible and complementary and their combination offers a satisfactory account of human psychology, appropriate for the understanding and integration of psychotherapy. PMID:1786224

  11. Extending the Framework of Generativity Theory Through Research: A Qualitative Study

    PubMed Central

    Rubinstein, Robert L.; Girling, Laura M.; de Medeiros, Kate; Brazda, Michael; Hannum, Susan

    2015-01-01

    Purpose of the study: Based on ethnographic interviews, we discuss three ideas we believe will expand knowledge of older informants’ thoughts about and representations of generativity. We adapt the notion of “dividuality” as developed in cultural anthropology to reframe ideas on generativity. The term dividuality refers to a condition of interpersonal or intergenerational connectedness, as distinct from individuality. We also extend previous definitions of generativity by identifying both objects of generative action and temporal and relational frameworks for generative action. Design: We define 4 foci of generativity (people, groups, things, and activities) and 4 spheres of generativity (historical, familial, individual, and relational) based in American culture and with which older informants could easily identify. The approach outlined here also discusses a form of generativity oriented to the past in which relationships with persons in senior generations form a kind of generative action since they are involved in caring for the origins of the self and hence of future generative acts. These 3 elements of a new framework will allow researchers to pose critical questions about generativity among older adults. Such questions include (a) How is the self, as culturally constituted, involved in generative action? and (b) What are the types of generativity within the context of American culture and how are they spoken about? Each of the above points is directly addressed in the data we present below. Methods: We defined these domains through extended ethnographic interviews with 200 older women. Results and implications: The article addresses some new ways of thinking about generativity as a construct, which may be useful in understanding the cultural personhood of older Americans. PMID:24704718

  12. A mixture fraction framework for the theory and modeling of droplets and sprays

    SciTech Connect

    Bilger, Robert W.

    2011-02-15

    A mixture fraction is carefully defined for evaporation and combustion of droplets and sprays. The definition is valid at points in either the liquid or gas phases and care is taken to distinguish between definitions based on conserved scalars appropriate for heat transfer and those for mass transfer. Results are presented for Spalding B numbers and values of the mixture fraction at the droplet surface for the fast chemistry case and for the case where the droplet cannot sustain an envelope flame. The classical theory for an isolated droplet with spherical symmetry yields simple formulae when expressed in mixture fraction terms. New results are then readily obtained for several quantities of interest in spray modeling. The formulation provides a seamless unification of droplet evaporation processes with gas-phase mixing and reaction. Mixing in a turbulent spray jet is identified as a model problem that clarifies the role of large scale structures in the overall mixing process. Important constraints on the parameter space for sprays are shown to be greatly clarified when expressed in the mixture fraction framework. It is shown how the classical approach for segregated flow with Eulerian/Lagrangian modeling of dispersion and transfer processes in turbulent sprays can be upgraded to include fluctuations in the temperature and composition surrounding the droplets on top of those coming from the turbulent velocity fluctuations. Such preliminary calculations that assume a simple chemically reacting system can readily be upgraded using flamelet functions derived from counterflow experiments or computations: these can then form the starting point for full chemistry calculations using such approaches as conditional moment closure. (author)

  13. Analyzing the substitution effect on the CoMFA results within the framework of density functional theory (DFT).

    PubMed

    Morales-Bayuelo, Alejandro

    2016-07-01

    Though QSAR was originally developed in the context of physical organic chemistry, it has been applied very extensively to chemicals (drugs) which act on biological systems, in this idea one of the most important QSAR methods is the 3D QSAR model. However, due to the complexity of understanding the results it is necessary to postulate new methodologies to highlight their physical-chemical meaning. In this sense, this work postulates new insights to understand the CoMFA results using molecular quantum similarity and chemical reactivity descriptors within the framework of density functional theory. To obtain these insights a simple theoretical scheme involving quantum similarity (overlap, coulomb operators, their euclidean distances) and chemical reactivity descriptors such as chemical potential (μ), hardness (ɳ), softness (S), electrophilicity (ω), and the Fukui functions, was used to understand the substitution effect. In this sense, this methodology can be applied to analyze the biological activity and the stabilization process in the non-covalent interactions on a particular molecular set taking a reference compound. PMID:27329189

  14. Unresolved issues in theories of autoimmune disease using myocarditis as a framework

    PubMed Central

    Root-Bernstein, Robert; Fairweather, DeLisa

    2014-01-01

    Many theories of autoimmune disease have been proposed since the discovery that the immune system can attack the body. These theories include the hidden or cryptic antigen theory, modified antigen theory, T cell bypass, T cell-B cell mismatch, epitope spread or drift, the bystander effect, molecular mimicry, anti-idiotype theory, antigenic complementarity, and dual-affinity T cell receptors. We critically review these theories and relevant mathematical models as they apply to autoimmune myocarditis. All theories share the common assumption that autoimmune diseases are triggered by environmental factors such as infections or chemical exposure. Most, but not all, theories and mathematical models are unifactorial assuming single-agent causation of disease. Experimental and clinical evidence and mathematical models exist to support some aspects of most theories, but evidence/models that support one theory almost invariably supports other theories as well. More importantly, every theory (and every model) lacks the ability to account for some key autoimmune disease phenomena such as the fundamental roles of innate immunity, sex differences in disease susceptibility, the necessity for adjuvants in experimental animal models, and the often paradoxical effect of exposure timing and dose on disease induction. We argue that a more comprehensive and integrated theory of autoimmunity associated with new mathematical models is needed and suggest specific experimental and clinical tests for each major theory that might help to clarify how they relate to clinical disease and reveal how theories are related. PMID:25484004

  15. A Disability Studies Framework for Policy Activism in Postsecondary Education

    ERIC Educational Resources Information Center

    Gabel, Susan L.

    2010-01-01

    This article uses disability studies and the social model of disability as theoretical foundations for policy activism in postsecondary education. The social model is discussed and a model for policy activism is described. A case study of how disability studies and policy activism can be applied is provided utilizing the "3C Project to Provide…

  16. Reference Framework for Active Learning in Higher Education

    ERIC Educational Resources Information Center

    Naithani, Pranav

    2008-01-01

    The work presented in this paper traces the history of active learning and further utilizes the available literature to define the meaning and importance of active learning in higher education. The study highlights common practical problems faced by students and instructors in implementing active learning in higher education and further identifies…

  17. Teachers' Knowing How to Use Technology: Exploring a Conceptual Framework for Purposeful Learning Activity

    ERIC Educational Resources Information Center

    Fisher, Tony; Denning, Tim; Higgins, Chris; Loveless, Avril

    2012-01-01

    This article describes a project to apply and validate a conceptual framework of clusters of purposeful learning activity involving ICT tools. The framework, which is based in a socio-cultural perspective, is described as "DECK", and comprises the following major categories of the use of digital technologies to support learning: distributed…

  18. Policy-Making Theory as an Analytical Framework in Policy Analysis: Implications for Research Design and Professional Advocacy.

    PubMed

    Sheldon, Michael R

    2016-01-01

    Policy studies are a recent addition to the American Physical Therapy Association's Research Agenda and are critical to our understanding of various federal, state, local, and organizational policies on the provision of physical therapist services across the continuum of care. Policy analyses that help to advance the profession's various policy agendas will require relevant theoretical frameworks to be credible. The purpose of this perspective article is to: (1) demonstrate the use of a policy-making theory as an analytical framework in a policy analysis and (2) discuss how sound policy analysis can assist physical therapists in becoming more effective change agents, policy advocates, and partners with other relevant stakeholder groups. An exploratory study of state agency policy responses to address work-related musculoskeletal disorders is provided as a contemporary example to illustrate key points and to demonstrate the importance of selecting a relevant analytical framework based on the context of the policy issue under investigation. PMID:26450973

  19. Evaluating the Consistency of Angoff-Based Cut Scores Using Subsets of Items within a Generalizability Theory Framework

    ERIC Educational Resources Information Center

    Kannan, Priya; Sgammato, Adrienne; Tannenbaum, Richard J.; Katz, Irvin R.

    2015-01-01

    The Angoff method requires experts to view every item on the test and make a probability judgment. This can be time consuming when there are large numbers of items on the test. In this study, a G-theory framework was used to determine if a subset of items can be used to make generalizable cut-score recommendations. Angoff ratings (i.e.,…

  20. A Theory of Information Quality and a Framework for Its Implementation in the Requirements Engineering Process

    ERIC Educational Resources Information Center

    Grenn, Michael W.

    2013-01-01

    This dissertation introduces a theory of information quality to explain macroscopic behavior observed in the systems engineering process. The theory extends principles of Shannon's mathematical theory of communication [1948] and statistical mechanics to information development processes concerned with the flow, transformation, and meaning of…

  1. Making sense in a complex landscape: how the Cynefin Framework from Complex Adaptive Systems Theory can inform health promotion practice.

    PubMed

    Van Beurden, Eric K; Kia, Annie M; Zask, Avigdor; Dietrich, Uta; Rose, Lauren

    2013-03-01

    Health promotion addresses issues from the simple (with well-known cause/effect links) to the highly complex (webs and loops of cause/effect with unpredictable, emergent properties). Yet there is no conceptual framework within its theory base to help identify approaches appropriate to the level of complexity. The default approach favours reductionism--the assumption that reducing a system to its parts will inform whole system behaviour. Such an approach can yield useful knowledge, yet is inadequate where issues have multiple interacting causes, such as social determinants of health. To address complex issues, there is a need for a conceptual framework that helps choose action that is appropriate to context. This paper presents the Cynefin Framework, informed by complexity science--the study of Complex Adaptive Systems (CAS). It introduces key CAS concepts and reviews the emergence and implications of 'complex' approaches within health promotion. It explains the framework and its use with examples from contemporary practice, and sets it within the context of related bodies of health promotion theory. The Cynefin Framework, especially when used as a sense-making tool, can help practitioners understand the complexity of issues, identify appropriate strategies and avoid the pitfalls of applying reductionist approaches to complex situations. The urgency to address critical issues such as climate change and the social determinants of health calls for us to engage with complexity science. The Cynefin Framework helps practitioners make the shift, and enables those already engaged in complex approaches to communicate the value and meaning of their work in a system that privileges reductionist approaches. PMID:22128193

  2. A New Framework for Cortico-Striatal Plasticity: Behavioural Theory Meets In Vitro Data at the Reinforcement-Action Interface

    PubMed Central

    Gurney, Kevin N.

    2015-01-01

    Operant learning requires that reinforcement signals interact with action representations at a suitable neural interface. Much evidence suggests that this occurs when phasic dopamine, acting as a reinforcement prediction error, gates plasticity at cortico-striatal synapses, and thereby changes the future likelihood of selecting the action(s) coded by striatal neurons. But this hypothesis faces serious challenges. First, cortico-striatal plasticity is inexplicably complex, depending on spike timing, dopamine level, and dopamine receptor type. Second, there is a credit assignment problem—action selection signals occur long before the consequent dopamine reinforcement signal. Third, the two types of striatal output neuron have apparently opposite effects on action selection. Whether these factors rule out the interface hypothesis and how they interact to produce reinforcement learning is unknown. We present a computational framework that addresses these challenges. We first predict the expected activity changes over an operant task for both types of action-coding striatal neuron, and show they co-operate to promote action selection in learning and compete to promote action suppression in extinction. Separately, we derive a complete model of dopamine and spike-timing dependent cortico-striatal plasticity from in vitro data. We then show this model produces the predicted activity changes necessary for learning and extinction in an operant task, a remarkable convergence of a bottom-up data-driven plasticity model with the top-down behavioural requirements of learning theory. Moreover, we show the complex dependencies of cortico-striatal plasticity are not only sufficient but necessary for learning and extinction. Validating the model, we show it can account for behavioural data describing extinction, renewal, and reacquisition, and replicate in vitro experimental data on cortico-striatal plasticity. By bridging the levels between the single synapse and behaviour, our

  3. [Behavioral Activation for Depression: Theory and Practice].

    PubMed

    Nakao, Tomohiro

    2015-01-01

    Behavioral activation (BA) has recently attracted marked attention. While cognitive therapy focuses on the cognitive distortion of patients with depression and asks them to change their behaviors as the process of altering the cognitive distortion, BA pays attention to behavior to avoid an unpleasant situation or social situation as a key symptom that leads to persistence of the depression. Avoidance behaviors are often seen during every process of depression, from onset to recurrence. Avoidance behaviors, a decrease in pleasant phenomena, or increase in unpleasant phenomena, result in reinforcing a depressive mood. If patients can set appropriate behavioral targets and achieve them, the beneficial behaviors will be further promoted with positive feed-back. The behavioral change, as-a consequence, will result in improvement of the mood, cognition, and depression itself. In this manuscript, the author presents two clinical cases, in which BA assisted the patients in recovering from their depression. The first case was a male in his thirties who repeatedly took sick leave from his work because of maladjustment, which resulted in persistent depression. The second case was a female in her thirties who suffered from OCD and then became maladjusted to her place of work, depressive, and emotionally unstable. In both cases, avoidant behaviors caused their conditions to persist. Appropriate activities formed by BA improved their moods, and their self-efficacies were gradually regained. It was suggested that BA is markedly effective, especially in patients whose avoidant behaviors mainly cause the persistence of their depressive symptoms. PMID:26514042

  4. Self-Efficacy Theory and the Theory of Planned Behavior: Teaching Physically Active Physical Education Classes

    ERIC Educational Resources Information Center

    Martin, Jeffrey J.; Kulinna, Pamela Hodges

    2004-01-01

    The purpose of this investigation was to examine determinants of teachers' intentions to teach physically active physical education classes (i.e., spend at least 50% of class time with the students engaged in moderate to vigorous physical activity). Based on the theory of planned behavior, a model was examined hypothesizing that teachers'…

  5. Studying Doctoral Education: Using Activity Theory to Shape Methodological Tools

    ERIC Educational Resources Information Center

    Beauchamp, Catherine; Jazvac-Martek, Marian; McAlpine, Lynn

    2009-01-01

    The study reported here, one part of a larger study on doctoral education, describes a pilot study that used Activity Theory to shape a methodological tool for better understanding the tensions inherent in the doctoral experience. As doctoral students may function within a range of activity systems, we designed data collection protocols based on…

  6. Narratives and Activity Theory as Reflective Tools in Action Research

    ERIC Educational Resources Information Center

    Stuart, Kaz

    2012-01-01

    Narratives and activity theory are useful as socially constructed data collection tools that allow a researcher access to the social, cultural and historical meanings that research participants place on events in their lives. This case study shows how these tools were used to promote reflection within a cultural-historical activity theoretically…

  7. Transformation or Transformism: Engestrom's Version of Activity Theory?

    ERIC Educational Resources Information Center

    Avis, James

    2009-01-01

    The paper examines Engestrom's version of activity theory. It seeks to locate this within the socio-economic and theoretical context in which notions of co-configuration and knotworking are set. Although this theoretical approach offers radical possibilities it is limited by its neglect of the wider social context in which activity systems are…

  8. Project-Based Language Learning: An Activity Theory Analysis

    ERIC Educational Resources Information Center

    Gibbes, Marina; Carson, Lorna

    2014-01-01

    This paper reports on an investigation of project-based language learning (PBLL) in a university language programme. Learner reflections of project work were analysed through Activity Theory, where tool-mediated activity is understood as the central unit of analysis for human interaction. Data were categorised according to the components of human…

  9. Rapidly assessing the activation conditions and porosity of metal-organic frameworks using thermogravimetric analysis

    SciTech Connect

    McDonald, TM; Bloch, ED; Long, JR

    2015-01-01

    A methodology utilizing a thermogravimetric analyzer to monitor propane uptake following incremental increases of the temperature is demonstrated as a means of rapidly identifying porous materials and determining the optimum activation conditions of metal-organic frameworks.

  10. The Legacy Ecosystem Management Framework: From Theory to Application in the Detention Pond Case Study

    SciTech Connect

    Coty, J; Stevenson, M; Vogt, K A

    2002-02-01

    The Detention Pond is a constructed and lined storm water treatment basin at Lawrence Livermore National Laboratory that serves multiple stakeholder objectives and programmatic goals. This paper examines the process and outcome involved in the development of a new management plan for the Detention Pond. The plan was created using a new ecosystem management tool, the Legacy Framework. This stakeholder-driven conceptual framework provides an interdisciplinary methodology for determining ecosystem health, appropriate management strategies, and sensitive indicators. The conceptual framework, the Detention Ponds project, and the use of the framework in the context of the project, are described and evaluated, and evaluative criteria for this and other ecosystem management frameworks are offered. The project benefited in several ways from use of the Legacy Framework, although refinements to the framework are suggested. The stakeholder process created a context and environment in which team members became receptive to using an ecosystem management approach to evaluate and support management alternatives previously not considered. This allowed for the unanimous agreement to pursue support from upper management and organizational funding to implement a progressive management strategy. The greatly improved stakeholder relations resulted in upper management support for the project.

  11. Predictors of African American Adolescent Sexual Activity: An Ecological Framework.

    ERIC Educational Resources Information Center

    Mandara, Jelani; Murray, Carolyn B.; Bangi, Audrey K.

    2003-01-01

    Investigated predictors of African American adolescent sexual activity, testing an ecological model of risk factors influencing sexual activity. Data collected over three years indicated that risk factors at the personal, familial, and extrafamilial levels of adolescents' social ecology related to being a virgin or not. Males and older adolescents…

  12. The Theory and Practice of Active Aging

    PubMed Central

    Fries, James F.

    2012-01-01

    Active aging” connotes a radically nontraditional paradigm of aging which posits possible improvement in health despite increasing longevity. The new paradigm is based upon postponing functional declines more than mortality declines and compressing morbidity into a shorter period later in life. This paradigm (Compression of Morbidity) contrasts with the old, where increasing longevity inevitably leads to increasing morbidity. We have focused our research on controlled longitudinal studies of aging. The Runners and Community Controls study began at age 58 in 1984 and the Health Risk Cohorts study at age 70 in 1986. We noted that disability was postponed by 14 to 16 years in vigorous exercisers compared with controls and postponed by 10 years in low-risk cohorts compared with higher risk. Mortality was also postponed, but too few persons had died for valid comparison of mortality and morbidity. With the new data presented here, age at death at 30% mortality is postponed by 7 years in Runners and age at death at 50% (median) mortality by 3.3 years compared to controls. Postponement of disability is more than double that of mortality in both studies. These differences increase over time, occur in all subgroups, and persist after statistical adjustment. PMID:23118746

  13. Bridging the gap between theory and practice: dynamic systems theory as a framework for understanding and promoting recovery of function in children and youth with acquired brain injuries.

    PubMed

    Levac, Danielle; DeMatteo, Carol

    2009-11-01

    A theoretical framework can help physiotherapists understand and promote recovery of function in children and youth with acquired brain injuries (ABI). Physiotherapy interventions for this population have traditionally been based in hierarchical-maturational theories of motor development emphasizing the role of the central nervous system (CNS) in controlling motor behaviour. In contrast, Dynamic Systems Theory (DST) views movement as resulting from the interaction of many subsystems within the individual, features of the functional task to be accomplished, and the environmental context in which the movement takes place. DST is now a predominant theoretical framework in pediatric physiotherapy. The purpose of this article is to describe how DST can be used to understand and promote recovery of function after pediatric ABI. A DST-based approach for children and youth with ABI does not treat the impaired CNS in isolation but rather emphasizes the role of all subsystems, including the family and the environment, in influencing recovery. The emphasis is on exploration, problem solving, and practice of functional tasks. A case scenario provides practical recommendations for the use of DST to inform physiotherapy interventions and clinical decision making in the acute phase of recovery from ABI. Future research is required to evaluate the effectiveness of interventions based in this theoretical framework. PMID:19925262

  14. Deriving Requirements for Pervasive Well-Being Technology From Work Stress and Intervention Theory: Framework and Case Study

    PubMed Central

    Koldijk, Saskia; Kraaij, Wessel

    2016-01-01

    Background Stress in office environments is a big concern, often leading to burn-out. New technologies are emerging, such as easily available sensors, contextual reasoning, and electronic coaching (e-coaching) apps. In the Smart Reasoning for Well-being at Home and at Work (SWELL) project, we explore the potential of using such new pervasive technologies to provide support for the self-management of well-being, with a focus on individuals' stress-coping. Ideally, these new pervasive systems should be grounded in existing work stress and intervention theory. However, there is a large diversity of theories and they hardly provide explicit directions for technology design. Objective The aim of this paper is to present a comprehensive and concise framework that can be used to design pervasive technologies that support knowledge workers to decrease stress. Methods Based on a literature study we identify concepts relevant to well-being at work and select different work stress models to find causes of work stress that can be addressed. From a technical perspective, we then describe how sensors can be used to infer stress and the context in which it appears, and use intervention theory to further specify interventions that can be provided by means of pervasive technology. Results The resulting general framework relates several relevant theories: we relate “engagement and burn-out” to “stress”, and describe how relevant aspects can be quantified by means of sensors. We also outline underlying causes of work stress and how these can be addressed with interventions, in particular utilizing new technologies integrating behavioral change theory. Based upon this framework we were able to derive requirements for our case study, the pervasive SWELL system, and we implemented two prototypes. Small-scale user studies proved the value of the derived technology-supported interventions. Conclusions The presented framework can be used to systematically develop theory

  15. Systems Theory as a Conceptual and Organizational Framework for Computational and Inferential Chemistry.

    ERIC Educational Resources Information Center

    Lacy, Mark E.

    1986-01-01

    Provides general background on basic concepts of systems theory. Discusses applications of systems theory to computational and inferential chemistry in molecular and reaction systems, systems analysis, and synthesis. Describes methodology for studying chemical systems by computer and gives advantages of an integrated computational environment. (JM)

  16. Middle-Range Theories: Frameworks for Examining a Nonsurgical Cosmetic Problem.

    PubMed

    Warren, Hermine

    2016-01-01

    The advent of evidence-based research has called for nursing to focus and create additional pathways that enable exploration of specific practice problems. This change of direction has presented an increased opportunity for analysis and scientific research that are pertinent to nursing. Although grand theory has historically been used to define and guide nursing research, currently many theorists have applied middle-range theories for these purposes. This level of theory provides substantive structures and foundations that may facilitate the ability to observe, test, and interpret phenomena so that a higher level of evidence-based research may be translated into practice. This article addresses and describes a selected clinical practice problem, reviews and assesses 2 middle-range theories, and finally, provides evaluation of the theories that will reaffirm how they support the practice problem. PMID:26933980

  17. Intrinsic flexibility of porous materials; theory, modelling and the flexibility window of the EMT zeolite framework

    PubMed Central

    Fletcher, Rachel E.; Wells, Stephen A.; Leung, Ka Ming; Edwards, Peter P.; Sartbaeva, Asel

    2015-01-01

    Framework materials have structures containing strongly bonded polyhedral groups of atoms connected through their vertices. Typically the energy cost for variations of the inter-polyhedral geometry is much less than the cost of distortions of the polyhedra themselves – as in the case of silicates, where the geometry of the SiO4 tetrahedral group is much more strongly constrained than the Si—O—Si bridging angle. As a result, framework materials frequently display intrinsic flexibility, and their dynamic and static properties are strongly influenced by low-energy collective motions of the polyhedra. Insight into these motions can be obtained in reciprocal space through the ‘rigid unit mode’ (RUM) model, and in real-space through template-based geometric simulations. We briefly review the framework flexibility phenomena in energy-relevant materials, including ionic conductors, perovskites and zeolites. In particular we examine the ‘flexibility window’ phenomenon in zeolites and present novel results on the flexibility window of the EMT framework, which shed light on the role of structure-directing agents. Our key finding is that the crown ether, despite its steric bulk, does not limit the geometric flexibility of the framework. PMID:26634720

  18. Developing theory-informed behaviour change interventions to implement evidence into practice: a systematic approach using the Theoretical Domains Framework

    PubMed Central

    2012-01-01

    Background There is little systematic operational guidance about how best to develop complex interventions to reduce the gap between practice and evidence. This article is one in a Series of articles documenting the development and use of the Theoretical Domains Framework (TDF) to advance the science of implementation research. Methods The intervention was developed considering three main components: theory, evidence, and practical issues. We used a four-step approach, consisting of guiding questions, to direct the choice of the most appropriate components of an implementation intervention: Who needs to do what, differently? Using a theoretical framework, which barriers and enablers need to be addressed? Which intervention components (behaviour change techniques and mode(s) of delivery) could overcome the modifiable barriers and enhance the enablers? And how can behaviour change be measured and understood? Results A complex implementation intervention was designed that aimed to improve acute low back pain management in primary care. We used the TDF to identify the barriers and enablers to the uptake of evidence into practice and to guide the choice of intervention components. These components were then combined into a cohesive intervention. The intervention was delivered via two facilitated interactive small group workshops. We also produced a DVD to distribute to all participants in the intervention group. We chose outcome measures in order to assess the mediating mechanisms of behaviour change. Conclusions We have illustrated a four-step systematic method for developing an intervention designed to change clinical practice based on a theoretical framework. The method of development provides a systematic framework that could be used by others developing complex implementation interventions. While this framework should be iteratively adjusted and refined to suit other contexts and settings, we believe that the four-step process should be maintained as the primary

  19. a Spatio-Temporal Framework for Modeling Active Layer Thickness

    NASA Astrophysics Data System (ADS)

    Touyz, J.; Streletskiy, D. A.; Nelson, F. E.; Apanasovich, T. V.

    2015-07-01

    The Arctic is experiencing an unprecedented rate of environmental and climate change. The active layer (the uppermost layer of soil between the atmosphere and permafrost that freezes in winter and thaws in summer) is sensitive to both climatic and environmental changes, and plays an important role in the functioning, planning, and economic activities of Arctic human and natural ecosystems. This study develops a methodology for modeling and estimating spatial-temporal variations in active layer thickness (ALT) using data from several sites of the Circumpolar Active Layer Monitoring network, and demonstrates its use in spatial-temporal interpolation. The simplest model's stochastic component exhibits no spatial or spatio-temporal dependency and is referred to as the naïve model, against which we evaluate the performance of the other models, which assume that the stochastic component exhibits either spatial or spatio-temporal dependency. The methods used to fit the models are then discussed, along with point forecasting. We compare the predicted fit of the various models at key study sites located in the North Slope of Alaska and demonstrate the advantages of space-time models through a series of error statistics such as mean squared error, mean absolute and percent deviance from observed data. We find the difference in performance between the spatio-temporal and remaining models is significant for all three error statistics. The best stochastic spatio-temporal model increases predictive accuracy, compared to the naïve model, of 33.3%, 36.2% and 32.5% on average across the three error metrics at the key sites for a one-year hold out period.

  20. A Critical New Pathway Towards Change in Abusive Relationships: The Theory of Transition Framework

    PubMed Central

    Shy, Yael

    2010-01-01

    This article explores the use of “Transition Framework” as a conceptual framework for individual and social change. William Bridges introduced Transition Framework in the 1970s as a three-pronged model explaining how people respond to change in their lives. This article argues that such an approach has the potential to help clients recognize and grieve the loss of their old identities, become comfortable with new ways of communicating, understand their cycles of relapse and make positive changes. The relevance of this model to transformative change in domestic violence treatment is explored. PMID:21170395

  1. Evaluation of a school-based intervention programme to promote physical activity: an application of the theory of planned behavior.

    PubMed

    Tsorbatzoudis, Haralambos

    2005-12-01

    The Theory of Planned Behavior provides a useful framework to study attitudes toward participation in physical activity. The objective of the study was to test the effectiveness of an intervention in manipulating the variables of the Theory of Planned Behavior and exercise habits with 366 high school students (M = 14.2 yr., SD = .7; 201 boys and 165 girls). The students were divided into intervention and control groups. A questionnaire to measure components of the theory, and the Baecke Questionnaire of Habitual Activity measuring exercise habits, were administered. The intervention lasted 12 wk. and included posters and lectures promoting participation in physical activity. Analyses showed the intervention was effective in improving attitudes towards physical activity, perceived behavioral control, intention, and self-reported actual behavior, but it was ineffective for improving attitude strength, subjective norms, and role identity. The results provide useful information for physical education teachers interested in promoting students' positive attitudes towards physical activity. PMID:16491680

  2. A Theory Bite on Learning through Mathematical Activity

    ERIC Educational Resources Information Center

    Steffe, Leslie P.

    2011-01-01

    In this article, the author wishes to emphasize two fundamental points related to theory that were significantly underplayed in Simon et al.'s "A Developing Approach to Studying Students' Learning through Their Mathematical Activity" (2010). The author believes these points are central to any study of children's mathematical learning. The first…

  3. Instructional Transaction Theory: Knowledge Relationships among Processes, Entities, and Activities.

    ERIC Educational Resources Information Center

    Merrill, M. David; And Others

    1993-01-01

    Discussion of instructional transaction theory focuses on knowledge representation in an automated instructional design expert system. A knowledge structure called PEA-Net (processes, entities, and activities) is explained; the refrigeration process is used as an example; text resources and graphic resources are described; and simulations are…

  4. Engestrom's Version of Activity Theory: A Conservative Praxis?

    ERIC Educational Resources Information Center

    Avis, James

    2007-01-01

    This article examines Engestrom's version of activity theory, one rooted in Marxism. It is argued that whilst this approach holds progressive possibilities, its radicalism is undermined by a restricted conceptualisation of transformation and the marginalisation of a politicised notion of social antagonism. As a consequence, this approach to…

  5. Anthropological Approach and Activity Theory: Culture, Communities and Institutions

    ERIC Educational Resources Information Center

    Lagrange, Jean-Baptiste

    2013-01-01

    The goal of this paper is to evaluate the contribution of the anthropological approach (AA) concurrently to Activity Theory (AT) in view of overarching questions about classroom use of technology for teaching and learning mathematics. I will do it first from a philosophical point of view, presenting the main notions of AA that have been used to…

  6. The Citizenship Development Framework: A Six Stage Socio/Cultural Theory.

    ERIC Educational Resources Information Center

    Dynneson, Thomas L.; Gross, Richard E.

    In order to understand the mechanisms of citizenship in the United States, people are required to study the interactions of ideology, education, and cultural pluralism as they are manifested in educational programs and in the processes of child development. The Citizenship Development Framework (CDF), a product of the Citizenship Development Study…

  7. Institutional Ethnography and Actor-Network Theory: A Framework for Researching the Assessment of Trainee Teachers

    ERIC Educational Resources Information Center

    Tummons, Jonathan

    2010-01-01

    This article provides an analysis of assessment practices on one university-led teacher-training course in England, delivered across a network of further education colleges. After establishing that assessment practices are bound up in texts of different kinds, this article draws on two theoretical frameworks--institutional ethnography and…

  8. Proposing a Theoretical Framework for Digital Age Youth Information Behavior Building upon Radical Change Theory

    ERIC Educational Resources Information Center

    Koh, Kyungwon

    2011-01-01

    Contemporary young people are engaged in a variety of information behaviors, such as information seeking, using, sharing, and creating. The ways youth interact with information have transformed in the shifting digital information environment; however, relatively little empirical research exists and no theoretical framework adequately explains…

  9. Knowing Inquiry as Practice and Theory: Developing a Pedagogical Framework with Elementary School Teachers

    ERIC Educational Resources Information Center

    Poon, Chew-Leng; Lee, Yew-Jin; Tan, Aik-Ling; Lim, Shirley S. L.

    2012-01-01

    In this paper, we characterize the inquiry practices of four elementary school teachers by means of a pedagogical framework. Our study revealed core components of inquiry found in theoretically-driven models as well as practices that were regarded as integral to the success of day-to-day science teaching in Singapore. This approach towards…

  10. White Dialectics: A New Framework for Theory, Research, and Practice with White Students

    ERIC Educational Resources Information Center

    Todd, Nathan R.; Abrams, Elizabeth M.

    2011-01-01

    This article presents White dialectics, or the tensions that White students experience as dominant group members in the United States, as a new framework to understand and intervene with White students and counselor trainees. Developed from and supported by our qualitative analysis, the authors present the six dialectics of (a) Whiteness and self,…

  11. Education and Outreach activities in the framework of the Spanish Virtual Observatory

    NASA Astrophysics Data System (ADS)

    Solano, E.; Rodrigo, C.

    2015-05-01

    In this paper we will describe the main education and outreach activities that are being conducted in the framework of the Spanish Virtual Observatory. In particular, we will outline the scientific and technical activities that are being done in collaboration with astronomical amateurs as well as the citizen science project to improve the orbits of near Earth asteroids using archive images.

  12. Towards a quantitative kinetic theory of polar active matter

    NASA Astrophysics Data System (ADS)

    Ihle, T.

    2014-06-01

    A recent kinetic approach for Vicsek-like models of active particles is reviewed. The theory is based on an exact Chapman- Kolmogorov equation in phase space. It can handle discrete time dynamics and "exotic" multi-particle interactions. A nonlocal mean-field theory for the one-particle distribution function is obtained by assuming molecular chaos. The Boltzmann approach of Bertin, et al., Phys. Rev. E 74, 022101 (2006) and J. Phys. A 42, 445001 (2009), is critically assessed and compared to the current approach. In Boltzmann theory, a collision starts when two particles enter each others action spheres and is finished when their distance exceeds the interaction radius. The average duration of such a collision, τ0, is measured for the Vicsek model with continuous time-evolution. If the noise is chosen to be close to the flocking threshold, the average time between collisions is found to be roughly equal to τ0 at low densities. Thus, the continuous-time Vicsek-model near the flocking threshold cannot be accurately described by a Boltzmann equation, even at very small density because collisions take so long that typically other particles join in, rendering Boltzmann's binary collision assumption invalid. Hydrodynamic equations for the phase space approach are derived by means of a Chapman-Enskog expansion. The equations are compared to the Toner-Tu theory of polar active matter. New terms, absent in the Toner-Tu theory, are highlighted. Convergence problems of Chapman-Enskog and similar gradient expansions are discussed.

  13. Divine action in the framework of scientific knowledge: From quantum theory to divine action

    NASA Astrophysics Data System (ADS)

    Lameter, Christoph

    During the Enlightenment, many theologians gave up the claim that God could act in the universe because the world was envisioned to be completely describable and governed by scientific laws. Surprisingly the development of quantum theory has resulted in the discovery of limits to causality, the universe is no longer conceived to be a closed system and therefore an account of divine action compatible with scientific theories might be possible now. First, the concept of divine intervention as envisioned in the nineteenth century is investigated and then a survey of the development of quantum theory is provided. The disputed character of the interpretation of quantum theory and of the measurement problem noted. It is suggested that the controversy continues because the straightforward acceptance of quantum theory---as already suggested by von Neumann in 1932---would imply a connection between mind and matter and question the notion of an objective, observer independent universe. It is shown using the literature on quantum theory that other solutions to the measurement problem are questionable on scientific grounds alone. Henry Stapp's recent rearticulation of von Neumann's arguments integrating them with Heisenberg's thinking is then selected as a potential basis for a theory of divine action. Existing theories of divine action are investigated starting with William James's idea of an indeterministic universe and ending with the contemporary approaches by Robert Russell and Nancey Murphy. Contemporary proposals are based on the notion of quantum events. A search is made for a scientific basis for quantum events but it is found that none of the interpretations of quantum theory would be compatible with the proposed idea of quantum events. Finally, a new theory of divine action is proposed understanding divine action as a holistic act, analogous to personal agency, through quantum determination. The universe is creating potentialities that are then collapsed by

  14. Principles of Catholic Social Teaching, Critical Pedagogy, and the Theory of Intersectionality: An Integrated Framework to Examine the Roles of Social Status in the Formation of Catholic Teachers

    ERIC Educational Resources Information Center

    Eick, Caroline Marie; Ryan, Patrick A.

    2014-01-01

    This article discusses the relevance of an analytic framework that integrates principles of Catholic social teaching, critical pedagogy, and the theory of intersectionality to explain attitudes toward marginalized youth held by Catholic students preparing to become teachers. The framework emerges from five years of action research data collected…

  15. A Conceptual Framework for a Psychometric Theory for Standard Setting with Examples of Its Use for Evaluating the Functioning of Two Standard Setting Methods

    ERIC Educational Resources Information Center

    Reckase, Mark D.

    2006-01-01

    A conceptual framework is proposed for a psychometric theory of standard setting. The framework suggests that participants in a standard setting process (panelists) develop an internal, intended standard as a result of training and the participant's background. The goal of a standard setting process is to convert panelists' intended standards to…

  16. Anatomy of life and well-being: A framework for the contributions of phenomenology and complexity theory

    PubMed Central

    Mugerauer, Robert

    2010-01-01

    This paper proposes an anatomy of the phenomena of life and of correlate qualitative modes of empirical research, theory, and professional practice concerned with health and well-being. I explicate the qualitative dynamic operative at every level of order, from the biological realm of cells and organisms, through distinctively human lifeworld experiences and practices, to communities of organisms in ecosystems and bio-cultural regions. This paper clarifies the unity of the dimensions of life and aligns these with demonstrated and emerging contributions of hermeneutical phenomenology and current complexity–autopoietic theory (including disciplinary and professional interpretations of empirical findings). The intent is begin to delineate a common framework upon which we could build—facilitating better understanding of the distinctive contributions of each specialization as well as the integration of diverse qualitative approaches with each other (and with quantitative complements). PMID:20616889

  17. A system framework of inter-enterprise machining quality control based on fractal theory

    NASA Astrophysics Data System (ADS)

    Zhao, Liping; Qin, Yongtao; Yao, Yiyong; Yan, Peng

    2014-03-01

    In order to meet the quality control requirement of dynamic and complicated product machining processes among enterprises, a system framework of inter-enterprise machining quality control based on fractal was proposed. In this system framework, the fractal-specific characteristic of inter-enterprise machining quality control function was analysed, and the model of inter-enterprise machining quality control was constructed by the nature of fractal structures. Furthermore, the goal-driven strategy of inter-enterprise quality control and the dynamic organisation strategy of inter-enterprise quality improvement were constructed by the characteristic analysis on this model. In addition, the architecture of inter-enterprise machining quality control based on fractal was established by means of Web service. Finally, a case study for application was presented. The result showed that the proposed method was available, and could provide guidance for quality control and support for product reliability in inter-enterprise machining processes.

  18. Kinetics of Hydrogen Radical Reactions with Toluene Including Chemical Activation Theory Employing System-Specific Quantum RRK Theory Calibrated by Variational Transition State Theory.

    PubMed

    Bao, Junwei Lucas; Zheng, Jingjing; Truhlar, Donald G

    2016-03-01

    Pressure-dependent reactions are ubiquitous in combustion and atmospheric chemistry. We employ a new calibration procedure for quantum Rice-Ramsperger-Kassel (QRRK) unimolecular rate theory within a chemical activation mechanism to calculate the pressure-falloff effect of a radical association with an aromatic ring. The new theoretical framework is applied to the reaction of H with toluene, which is a prototypical reaction in the combustion chemistry of aromatic hydrocarbons present in most fuels. Both the hydrogen abstraction reactions and the hydrogen addition reactions are calculated. Our system-specific (SS) QRRK approach is adjusted with SS parameters to agree with multistructural canonical variational transition state theory with multidimensional tunneling (MS-CVT/SCT) at the high-pressure limit. The new method avoids the need for the usual empirical estimations of the QRRK parameters, and it eliminates the need for variational transition state theory calculations as a function of energy, although in this first application we do validate the falloff curves by comparing SS-QRRK results without tunneling to multistructural microcanonical variational transition state theory (MS-μVT) rate constants without tunneling. At low temperatures, the two approaches agree well with each other, but at high temperatures, SS-QRRK tends to overestimate falloff slightly. We also show that the variational effect is important in computing the energy-resolved rate constants. Multiple-structure anharmonicity, torsional-potential anharmonicity, and high-frequency-mode vibrational anharmonicity are all included in the rate computations, and torsional anharmonicity effects on the density of states are investigated. Branching fractions, which are both temperature- and pressure-dependent (and for which only limited data is available from experiment), are predicted as a function of pressure. PMID:26841076

  19. Boosting theory towards practice: Recent developments in decision tree induction and the weak learning framework

    SciTech Connect

    Kearns, M.

    1996-12-31

    One of the original goals of computational learning theory was that of formulating models that permit meaningful comparisons between the different machine learning heuristics that are used in practice [Kearns et al., 1987]. Despite the other successes of computational learning theory, this goal has proven elusive. Empirically successful machine learning algorithms such as C4.5 and the backpropagation algorithm for neural networks have not met the criteria of the well-known Probably Approximately Correct (PAC) model [Valiant, 1984] and its variants, and thus such models are of little use in drawing distinctions among the heuristics used in applications. Conversely, the algorithms suggest by computational learning theory are usually too limited in various ways to find wide application.

  20. Theoretical frameworks for testing relativistic gravity. 5: Post-Newtonian limit of Rosen's theory

    NASA Technical Reports Server (NTRS)

    Lee, D. L.; Caves, C. M.

    1974-01-01

    The post-Newtonian limit of Rosen's theory of gravity is evaluated and is shown to be identical to that of general relativity, except for the PPN parameter alpha sub 2, which is related to the difference in propagation speeds for gravitational and electromagnetic waves. Both the value of alpha sub 2 and the value of the Newtonian gravitational constant depend on the present cosmological structure of the Universe. If the cosmological structure has a specific but presumably special form, the Newtonian gravitational constant assumes its current value, alpha sub 2 is zero, the post-Newtonian limit of Rosen's theory is identical to that of general relativity--and standard solar system experiments cannot distinguish between the two theories.

  1. Theoretical frameworks for testing relativistic gravity. V - Post-Newtonian limit of Rosen's theory

    NASA Technical Reports Server (NTRS)

    Lee, D. L.; Ni, W.-T.; Caves, C. M.; Will, C. M.

    1976-01-01

    The post-Newtonian limit of Rosen's theory of gravity is evaluated and is shown to be identical to that of general relativity, except for the post-Newtonian parameter alpha sub 2 (which is related to the difference in propagation speeds for gravitational and electromagnetic waves). Both the value of alpha sub 2 and the value of the Newtonian gravitational constant depend on the present cosmological structure of the Universe. If the cosmological structure has a specific (but presumably special) form, the Newtonian gravitational constant assumes its current value, alpha sub 2 is zero, the post-Newtonian limit of Rosen's theory is identical to that of general relativity - and standard solar system experiments cannot distinguish between the two theories.

  2. Quantum field theory with a preferred direction: The very special relativity framework

    NASA Astrophysics Data System (ADS)

    Lee, Cheng-Yang

    2016-02-01

    The theory of very special relativity (VSR) proposed by Cohen and Glashow contains an intrinsic preferred direction. Starting from the irreducible unitary representation of the inhomogeneous VSR group I S I M (2 ), we present a rigorous construction of quantum field theory with a preferred direction. We find that although the particles and their quantum fields between the VSR and Lorentz sectors are physically different, they share many similarities. The massive spin-half and spin-one vector fields are local and satisfy the Dirac and Proca equations, respectively. This result can be generalized to higher-spin field theories. By studying the Yukawa and standard gauge interactions, we obtain a qualitative understanding on the effects of the preferred direction. Its effect is manifest for polarized processes but are otherwise absent.

  3. A new framework for comprehensive, robust, and efficient global sensitivity analysis: 1. Theory

    NASA Astrophysics Data System (ADS)

    Razavi, Saman; Gupta, Hoshin V.

    2016-01-01

    Computer simulation models are continually growing in complexity with increasingly more factors to be identified. Sensitivity Analysis (SA) provides an essential means for understanding the role and importance of these factors in producing model responses. However, conventional approaches to SA suffer from (1) an ambiguous characterization of sensitivity, and (2) poor computational efficiency, particularly as the problem dimension grows. Here, we present a new and general sensitivity analysis framework (called VARS), based on an analogy to "variogram analysis," that provides an intuitive and comprehensive characterization of sensitivity across the full spectrum of scales in the factor space. We prove, theoretically, that Morris (derivative-based) and Sobol (variance-based) methods and their extensions are special cases of VARS, and that their SA indices can be computed as by-products of the VARS framework. Synthetic functions that resemble actual model response surfaces are used to illustrate the concepts, and show VARS to be as much as two orders of magnitude more computationally efficient than the state-of-the-art Sobol approach. In a companion paper, we propose a practical implementation strategy, and demonstrate the effectiveness, efficiency, and reliability (robustness) of the VARS framework on real-data case studies.

  4. Vygotsky as Precursor to Metacognitive Theory: III. Recent Metacognitive Research within a Vygotskian Framework.

    ERIC Educational Resources Information Center

    Braten, Ivar

    1992-01-01

    This third article of a series reviews recent metacognitive projects inspired by the theory of L. S. Vygotsky. These projects include research on (1) children's memory development; (2) the mother-child dyad; (3) the origin and function of adaptive inner speech; and (4) problem learners. (SLD)

  5. Parent-Offspring Conflict Theory: An Evolutionary Framework for Understanding Conflict within Human Families

    ERIC Educational Resources Information Center

    Schlomer, Gabriel L.; Del Giudice, Marco; Ellis, Bruce J.

    2011-01-01

    Decades of research demonstrate that conflict shapes and permeates a broad range of family processes. In the current article, we argue that greater insight, integration of knowledge, and empirical achievement in the study of family conflict can be realized by utilizing a powerful theory from evolutionary biology that is barely known within…

  6. Place-Building Theory: A Framework for Assessing and Advancing Community Engagement in Higher Education

    ERIC Educational Resources Information Center

    Kimball, Michael J.; Thomas, David F.

    2012-01-01

    Place-building theory, originally developed to assess corporate social responsibility, explains to what degree an organization values and invests in its geographical and social location. Different lines of inquiry--descriptive, evaluative, and prescriptive--elucidate how the organization values place, which in turn suggests its type, its…

  7. Transactional Analysis as a Conceptual Framework: Directed Individual Study in Contemporary Theories.

    ERIC Educational Resources Information Center

    Richards, Bob

    The theory of transactional analysis (TA) originated by Eric Berne in the 1950's is typified by structural analysis and is comprised of the ego states of Parent, Adult, and Child. Linkages are the life scripts of the individual. One ego state is usually in control at any given time. Pathology results when ego boundaries become rigid or break down…

  8. Making a Map of Science: General Systems Theory as a Conceptual Framework for Tertiary Science Education.

    ERIC Educational Resources Information Center

    Gulyaev, Sergei A.; Stonyer, Heather R.

    2002-01-01

    Develops an integrated approach based on the use of general systems theory (GST) and the concept of 'mapping' scientific knowledge to provide students with tools for a more holistic understanding of science. Uses GST as the core methodology for understanding science and its complexity. Discusses the role of scientific community in producing…

  9. A Qualitative Analysis Framework Using Natural Language Processing and Graph Theory

    ERIC Educational Resources Information Center

    Tierney, Patrick J.

    2012-01-01

    This paper introduces a method of extending natural language-based processing of qualitative data analysis with the use of a very quantitative tool--graph theory. It is not an attempt to convert qualitative research to a positivist approach with a mathematical black box, nor is it a "graphical solution". Rather, it is a method to help qualitative…

  10. Organizational Learning, Change and Power: Toward a Practice-Theory Framework

    ERIC Educational Resources Information Center

    Ford, Randal

    2006-01-01

    Purpose: The purpose of this research is to investigate the practices of the interim and current CEOs employed in managing a supportive environment conducive for learning as well as sustaining organizational change; and second, to describe the theory of practice guiding their efforts. Design/methodology/approach: An action science approach,…

  11. Using the Theory of Successful Intelligence as a Framework for Developing Assessments in AP Physics

    ERIC Educational Resources Information Center

    Stemler, Steven E.; Sternberg, Robert J.; Grigorenko, Elena L.; Jarvin, Linda; Sharpes, Kirsten

    2009-01-01

    A new test of Advanced Placement Physics, explicitly designed to balance both content and cognitive-processing skills, was developed using Sternberg's theory of successful intelligence. The test was administered to 281 AP Physics students from 10 schools during the 2006-2007 school year. Six empirically distinguishable profiles of strengths and…

  12. Tailoring Healthy Workplace Interventions to Local Healthcare Settings: A Complexity Theory-Informed Workplace of Well-Being Framework

    PubMed Central

    Brand, Sarah L.; Fleming, Lora E.; Wyatt, Katrina M.

    2015-01-01

    Many healthy workplace interventions have been developed for healthcare settings to address the consistently low scores of healthcare professionals on assessments of mental and physical well-being. Complex healthcare settings present challenges for the scale-up and spread of successful interventions from one setting to another. Despite general agreement regarding the importance of the local setting in affecting intervention success across different settings, there is no consensus on what it is about a local setting that needs to be taken into account to design healthy workplace interventions appropriate for different local settings. Complexity theory principles were used to understand a workplace as a complex adaptive system and to create a framework of eight domains (system characteristics) that affect the emergence of system-level behaviour. This Workplace of Well-being (WoW) framework is responsive and adaptive to local settings and allows a shared understanding of the enablers and barriers to behaviour change by capturing local information for each of the eight domains. We use the results of applying the WoW framework to one workplace, a UK National Health Service ward, to describe the utility of this approach in informing design of setting-appropriate healthy workplace interventions that create workplaces conducive to healthy behaviour change. PMID:26380358

  13. Under which conditions, additional monitoring data are worth gathering for improving decision making? Application of the VOI theory in the Bayesian Event Tree eruption forecasting framework

    NASA Astrophysics Data System (ADS)

    Loschetter, Annick; Rohmer, Jérémy

    2016-04-01

    . For the parameters that concern expert setting, the weight attributed to monitoring measurement ω, the mean of thresholds, the economic context and the setting of the decision threshold are very influential. The interest of applying the VOI theory (more precisely the value of imperfect information) in the BET framework was demonstrated as support for helping experts in the setting of the monitoring system or for helping managers to decide the installation of additional monitoring systems. Acknowledgments: This work was carried out in the framework of the project MEDSUV. This project is funded under the call FP7 ENV.2012.6.4-2: Long-term monitoring experiment in geologically active regions of Europe prone to natural hazards: the Supersite concept. Grant agreement n°308665.

  14. Using Principal-Agent Theory as a Framework for Analysis in Evaluating the Multiple Stakeholders Involved in the Accreditation and Quality Assurance of International Medical Branch Campuses

    ERIC Educational Resources Information Center

    Borgos, Jill E.

    2013-01-01

    This article applies the theoretical framework of principal-agent theory in order to better understand the complex organisational relationships emerging between entities invested in the establishment and monitoring of cross-border international branch campus medical schools. Using the key constructs of principal-agent theory, information asymmetry…

  15. Assessment of Student Performance in a PSI College Physics Course Using Ausubel's Learning Theory as a Theoretical Framework for Content Organization.

    ERIC Educational Resources Information Center

    Moriera, M. A.

    1979-01-01

    David Ausubel's learning theory was used as a framework for the content organization of an experimental Personalized System of Instruction (PSI) course in physics. Evaluation suggests that the combination of PSI as a method of instruction and Ausubel's theory for organization might result in better learning outcomes. (Author/JMD)

  16. A computational framework for polyconvex large strain elasticity for geometrically exact beam theory

    NASA Astrophysics Data System (ADS)

    Ortigosa, Rogelio; Gil, Antonio J.; Bonet, Javier; Hesch, Christian

    2016-02-01

    In this paper, a new computational framework is presented for the analysis of nonlinear beam finite elements subjected to large strains. Specifically, the methodology recently introduced in Bonet et al. (Comput Methods Appl Mech Eng 283:1061-1094, 2015) in the context of three dimensional polyconvex elasticity is extended to the geometrically exact beam model of Simo (Comput Methods Appl Mech Eng 49:55-70, 1985), the starting point of so many other finite element beam type formulations. This new variational framework can be viewed as a continuum degenerate formulation which, moreover, is enhanced by three key novelties. First, in order to facilitate the implementation of the sophisticated polyconvex constitutive laws particularly associated with beams undergoing large strains, a novel tensor cross product algebra by Bonet et al. (Comput Methods Appl Mech Eng 283:1061-1094, 2015) is adopted, leading to an elegant and physically meaningful representation of an otherwise complex computational framework. Second, the paper shows how the novel algebra facilitates the re-expression of any invariant of the deformation gradient, its cofactor and its determinant in terms of the classical beam strain measures. The latter being very useful whenever a classical beam implementation is preferred. This is particularised for the case of a Mooney-Rivlin model although the technique can be straightforwardly generalised to other more complex isotropic and anisotropic polyconvex models. Third, the connection between the two most accepted restrictions for the definition of constitutive models in three dimensional elasticity and beams is shown, bridging the gap between the continuum and its degenerate beam description. This is carried out via a novel insightful representation of the tangent operator.

  17. Benchmarking density functional theory predictions of framework structures and properties in a chemically diverse test set of metal-organic frameworks

    SciTech Connect

    Nazarian, Dalar; Ganesh, P.; Sholl, David S.

    2015-09-30

    We compiled a test set of chemically and topologically diverse Metal–Organic Frameworks (MOFs) with high accuracy experimentally derived crystallographic structure data. The test set was used to benchmark the performance of Density Functional Theory (DFT) functionals (M06L, PBE, PW91, PBE-D2, PBE-D3, and vdW-DF2) for predicting lattice parameters, unit cell volume, bonded parameters and pore descriptors. On average PBE-D2, PBE-D3, and vdW-DF2 predict more accurate structures, but all functionals predicted pore diameters within 0.5 Å of the experimental diameter for every MOF in the test set. The test set was also used to assess the variance in performance of DFT functionals for elastic properties and atomic partial charges. The DFT predicted elastic properties such as minimum shear modulus and Young's modulus can differ by an average of 3 and 9 GPa for rigid MOFs such as those in the test set. Moreover, we calculated the partial charges by vdW-DF2 deviate the most from other functionals while there is no significant difference between the partial charges calculated by M06L, PBE, PW91, PBE-D2 and PBE-D3 for the MOFs in the test set. We find that while there are differences in the magnitude of the properties predicted by the various functionals, these discrepancies are small compared to the accuracy necessary for most practical applications.

  18. Testing Theory of Planned Behavior and Neo-Socioanalytic Theory models of trait activity, industriousness, exercise social cognitions, exercise intentions, and physical activity in a representative U.S. sample

    PubMed Central

    Vo, Phuong T.; Bogg, Tim

    2015-01-01

    Prior research identified assorted relations between trait and social cognition models of personality and engagement in physical activity. Using a representative U.S. sample (N = 957), the goal of the present study was to test two alternative structural models of the relationships among the extraversion-related facet of activity, the conscientiousness-related facet of industriousness, social cognitions from the Theory of Planned Behavior (perceived behavioral control, affective attitudes, subjective norms, intentions), Social Cognitive Theory (self-efficacy, outcome expectancies), and the Transtheoretical Model (behavioral processes of change), and engagement in physical activity. Path analyses with bootstrapping procedures were used to model direct and indirect effects of trait and social cognition constructs on physical activity through two distinct frameworks – the Theory of Planned Behavior and Neo-Socioanalytic Theory. While both models showed good internal fit, comparative model information criteria showed the Theory-of-Planned-Behavior-informed model provided a better fit. In the model, social cognitions fully mediated the relationships from the activity facet and industriousness to intentions for and engagement in physical activity, such that the relationships were primarily maintained by positive affective evaluations, positive expected outcomes, and confidence in overcoming barriers related to physical activity engagement. The resultant model – termed the Disposition-Belief-Motivation model– is proposed as a useful framework for organizing and integrating personality trait facets and social cognitions from various theoretical perspectives to investigate the expression of health-related behaviors, such as physical activity. Moreover, the results are discussed in terms of extending the application of the Disposition-Belief-Motivation model to longitudinal and intervention designs for physical activity engagement. PMID:26300811

  19. Testing Theory of Planned Behavior and Neo-Socioanalytic Theory models of trait activity, industriousness, exercise social cognitions, exercise intentions, and physical activity in a representative U.S. sample.

    PubMed

    Vo, Phuong T; Bogg, Tim

    2015-01-01

    Prior research identified assorted relations between trait and social cognition models of personality and engagement in physical activity. Using a representative U.S. sample (N = 957), the goal of the present study was to test two alternative structural models of the relationships among the extraversion-related facet of activity, the conscientiousness-related facet of industriousness, social cognitions from the Theory of Planned Behavior (perceived behavioral control, affective attitudes, subjective norms, intentions), Social Cognitive Theory (self-efficacy, outcome expectancies), and the Transtheoretical Model (behavioral processes of change), and engagement in physical activity. Path analyses with bootstrapping procedures were used to model direct and indirect effects of trait and social cognition constructs on physical activity through two distinct frameworks - the Theory of Planned Behavior and Neo-Socioanalytic Theory. While both models showed good internal fit, comparative model information criteria showed the Theory-of-Planned-Behavior-informed model provided a better fit. In the model, social cognitions fully mediated the relationships from the activity facet and industriousness to intentions for and engagement in physical activity, such that the relationships were primarily maintained by positive affective evaluations, positive expected outcomes, and confidence in overcoming barriers related to physical activity engagement. The resultant model - termed the Disposition-Belief-Motivation model- is proposed as a useful framework for organizing and integrating personality trait facets and social cognitions from various theoretical perspectives to investigate the expression of health-related behaviors, such as physical activity. Moreover, the results are discussed in terms of extending the application of the Disposition-Belief-Motivation model to longitudinal and intervention designs for physical activity engagement. PMID:26300811

  20. Comparing Educational Tools Using Activity Theory: Clickers and Flashcards

    NASA Astrophysics Data System (ADS)

    Price, Edward; De Leone, Charles; Lasry, Nathaniel

    2010-10-01

    Physics educators and researchers have recently begun to distinguish between pedagogical approaches and the educational technologies that are used to implement them. For instance, peer instruction has been shown to be equally effective, in terms of student learning outcomes, when implemented with clickers or flashcards. Therefore, technological tools (clickers and flashcards) can be viewed as means to mediate pedagogical techniques (peer instruction or traditional instruction). In this paper, we use activity theory to examine peer instruction, with particular attention to the role of tools. This perspective helps clarify clickers' and flashcards' differences, similarities, impacts in the classroom, and utility to education researchers. Our analysis can suggest improvements and new uses. Finally, we propose activity theory as a useful approach in understanding and improving the use of technology in the physics classroom.

  1. Pedagogical Distance: Explaining Misalignment in Student-Driven Online Learning Activities Using Activity Theory

    ERIC Educational Resources Information Center

    Westberry, Nicola; Franken, Margaret

    2015-01-01

    This paper provides an Activity Theory analysis of two online student-driven interactive learning activities to interrogate assumptions that such groups can effectively learn in the absence of the teacher. Such an analysis conceptualises learning tasks as constructed objects that drive pedagogical activity. The analysis shows a disconnect between…

  2. Understanding Small-Molecule Interactions in Metal-Organic Frameworks: Coupling Experiment with Theory.

    PubMed

    Lee, Jason S; Vlaisavljevich, Bess; Britt, David K; Brown, Craig M; Haranczyk, Maciej; Neaton, Jeffrey B; Smit, Berend; Long, Jeffrey R; Queen, Wendy L

    2015-10-14

    Metal-organic frameworks (MOFs) have gained much attention as next-generation porous media for various applications, especially gas separation/storage, and catalysis. New MOFs are regularly reported; however, to develop better materials in a timely manner for specific applications, the interactions between guest molecules and the internal surface of the framework must first be understood. A combined experimental and theoretical approach is presented, which proves essential for the elucidation of small-molecule interactions in a model MOF system known as M2 (dobdc) (dobdc(4-) = 2,5-dioxido-1,4-benzenedicarboxylate; M = Mg, Mn, Fe, Co, Ni, Cu, or Zn), a material whose adsorption properties can be readily tuned via chemical substitution. It is additionally shown that the study of extensive families like this one can provide a platform to test the efficacy and accuracy of developing computational methodologies in slightly varying chemical environments, a task that is necessary for their evolution into viable, robust tools for screening large numbers of materials. PMID:26033176

  3. Cosmology without Big Bang within the framework of the Projective Unified Field Theory and the influence on the motion of cosmic objects

    NASA Astrophysics Data System (ADS)

    Schmutzer, E.

    The Projective Unified Field Theory having been developed by the author since 1957 is applied to a closed homogeneous isotropic cosmological model. By postulating a (new) conservation law for the scalaric substrate mass (derived from the balance equation of matter and leading to a basically new view on the concept of mass in context with the Mach principle) we obtained a coupled system of differential equations for the world radius and the scalaric world function, which could be treated numerically by Maple. Detailed calculations show that the big bang singularity of the Einstein theory can be avoided. Since the mass density and the temperature of the background radiation exhibit maxima at the same time after the cosmological ``big start'', this fact could be of interest for cosmogonic activities. Within the framework of this theory there are hints for an antigravitational world era with repulsive forces after the big start. Furthermore, the balance equations for the energy and the angular momentum of a body as well as the equation of motion of a body (with a series of consequences) are derived. In this context we found a formula for the time dependence of the ``effective Newtonian gravitational constant''. Further results refer to certain aspects for understanding the observed rotational curves of cosmic objects within galaxies as well as to the conservation of the number of photons and baryons and their mutual ratio etc.

  4. A multidimensional analysis of the epistemic origins of nursing theories, models, and frameworks.

    PubMed

    Beckstead, Jason W; Beckstead, Laura Grace

    2006-01-01

    The purpose of this article is to introduce our notion of epistemic space and to demonstrate its utility for understanding the origins and trajectories of nursing theory in the 20th century using multidimensional scaling (MDS). A literature review was conducted on primary and secondary sources written by and about 20 nurse theorists to investigate whether or not they cited 129 different scholars in the fields of anthropology, biology, nursing, philosophy, psychology, and sociology. Seventy-four scholars were identified as having been cited by at least two nurse theorists (319 citations total). Proximity scores, quantifying the similarity among nurse theorists based on proportions of shared citations, were calculated and analyzed using MDS. The emergent model of epistemic space that accommodated these similarities among nurse theorists revealed the systematic influence of scholars from various fields, notably psychology, biology, and philosophy. We believe that this schema and resulting taxonomy will prove useful for furthering our understanding of the relationships among nursing theories and theories in other fields of science. PMID:16326166

  5. Games and Diabetes: A Review Investigating Theoretical Frameworks, Evaluation Methodologies, and Opportunities for Design Grounded in Learning Theories.

    PubMed

    Lazem, Shaimaa; Webster, Mary; Holmes, Wayne; Wolf, Motje

    2016-03-01

    Here we review 18 articles that describe the design and evaluation of 1 or more games for diabetes from technical, methodological, and theoretical perspectives. We undertook searches covering the period 2010 to May 2015 in the ACM, IEEE, Journal of Medical Internet Research, Studies in Health Technology and Informatics, and Google Scholar online databases using the keywords "children," "computer games," "diabetes," "games," "type 1," and "type 2" in various Boolean combinations. The review sets out to establish, for future research, an understanding of the current landscape of digital games designed for children with diabetes. We briefly explored the use and impact of well-established learning theories in such games. The most frequently mentioned theoretical frameworks were social cognitive theory and social constructivism. Due to the limitations of the reported evaluation methodologies, little evidence was found to support the strong promise of games for diabetes. Furthermore, we could not establish a relation between design features and the game outcomes. We argue that an in-depth discussion about the extent to which learning theories could and should be manifested in the design decisions is required. PMID:26337753

  6. ActiveTutor: Towards More Adaptive Features in an E-Learning Framework

    ERIC Educational Resources Information Center

    Fournier, Jean-Pierre; Sansonnet, Jean-Paul

    2008-01-01

    Purpose: This paper aims to sketch the emerging notion of auto-adaptive software when applied to e-learning software. Design/methodology/approach: The study and the implementation of the auto-adaptive architecture are based on the operational framework "ActiveTutor" that is used for teaching the topic of computer science programming in first-grade…

  7. A Framework For Using GPS Data In Physical Activity And Sedentary Behavior Studies

    PubMed Central

    Jankowska, Marta M.; Schipperijn, Jasper; Kerr, Jacqueline

    2014-01-01

    Global Positioning Systems (GPS) are increasingly applied in activity studies, yet significant theoretical and methodological challenges remain. This paper presents a framework for integrating GPS data with other technologies to create dynamic representations of behaviors in context. Utilizing more accurate and sensitive measures to link behavior and environmental exposures allows for new research questions and methods to be developed. PMID:25390297

  8. Using the RE-AIM framework to evaluate physical activity public health programs in Mexico

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Physical activity (PA) public health programming has been widely used in Mexico; however, few studies have documented individual and organizational factors that might be used to evaluate their public health impact. The RE-AIM framework is an evaluation tool that examines individual and organizationa...

  9. A Framework for Physical Activity Programs within School-Community Partnerships

    ERIC Educational Resources Information Center

    Van Acker, Ragnar; De Bourdeaudhuij, Ilse; De Martelaer, Kristine; Seghers, Jan; Kirk, David; Haerens, Leen; De Cocker, Katrien; Cardon, Greet

    2011-01-01

    School-community partnerships have shown their potential as incubators for innovations and for contributing to comprehensive physical activity (PA) programs. However, implementation frameworks for school-community partnerships that allow local tailoring of PA programs remain scarce. The present paper aims at documenting the composition of a…

  10. Designing a robust activity recognition framework for health and exergaming using wearable sensors.

    PubMed

    Alshurafa, Nabil; Xu, Wenyao; Liu, Jason J; Huang, Ming-Chun; Mortazavi, Bobak; Roberts, Christian K; Sarrafzadeh, Majid

    2014-09-01

    Detecting human activity independent of intensity is essential in many applications, primarily in calculating metabolic equivalent rates and extracting human context awareness. Many classifiers that train on an activity at a subset of intensity levels fail to recognize the same activity at other intensity levels. This demonstrates weakness in the underlying classification method. Training a classifier for an activity at every intensity level is also not practical. In this paper, we tackle a novel intensity-independent activity recognition problem where the class labels exhibit large variability, the data are of high dimensionality, and clustering algorithms are necessary. We propose a new robust stochastic approximation framework for enhanced classification of such data. Experiments are reported using two clustering techniques, K-Means and Gaussian Mixture Models. The stochastic approximation algorithm consistently outperforms other well-known classification schemes which validate the use of our proposed clustered data representation. We verify the motivation of our framework in two applications that benefit from intensity-independent activity recognition. The first application shows how our framework can be used to enhance energy expenditure calculations. The second application is a novel exergaming environment aimed at using games to reward physical activity performed throughout the day, to encourage a healthy lifestyle. PMID:24235280

  11. A Variational Framework for Spectral Approximations of Kohn-Sham Density Functional Theory

    NASA Astrophysics Data System (ADS)

    Wang, Xin-Cindy; Blesgen, Thomas; Bhattacharya, Kaushik; Ortiz, Michael

    2016-08-01

    We reformulate the Kohn-Sham density functional theory (KSDFT) as a nested variational problem in the one-particle density operator, the electrostatic potential and a field dual to the electron density. The corresponding functional is linear in the density operator and thus amenable to spectral representation. Based on this reformulation, we introduce a new approximation scheme, termed spectral binning, which does not require smoothing of the occupancy function and thus applies at arbitrarily low temperatures. We prove convergence of the approximate solutions with respect to spectral binning and with respect to an additional spatial discretization of the domain.

  12. Making a map of science: general systems theory as a conceptual framework for tertiary science education

    NASA Astrophysics Data System (ADS)

    Gulyaev, Sergei A.; Stonyer, Heather R.

    2002-07-01

    As a result of the reductionist approach to science curricula in tertiary education, students are learning science in a fragmented way. With the purpose of providing students with tools for a more holistic understanding of science, an integrated approach based on the use of general systems theory (GST) and the concept of 'mapping' scientific knowledge (its relationships, connections and generalities) is developed. GST is used as the core methodology for understanding science and its complexity. By analogy with geographic maps, we introduce scales of educational 'science maps' - scales of integration. Three principal scales of integration can be distinguished in GST, which we consider necessary for GST to be effectively applied in education. They are (a) the scale of branches and fields of science, (b) the scale of hypotheses and theories, and (c) the scale of structures and hierarchies. Examples of each of these three scales are provided from the field of physical science. The role of the scientific community in producing accessible, and essential, maps of scientific knowledge for science education is discussed.

  13. Building inhabitant feedback: Creating a reflective practice for environmental design using activity theory

    NASA Astrophysics Data System (ADS)

    Cunningham, Dara Suzanne

    The way buildings are designed now, there is little feedback from use involved in the design process. Attempts to correct this problem have been made in the form of Post Occupancy Evaluations (POEs) for 50-years but have largely failed. POEs are the accepted method for environmental designers to collect feedback about buildings in use. They are infrequently conducted, after the building is built, in a one-time only evaluation, and not funded as part of the build process. Other products receive feedback about the design in use from online critiques. Online critiques could provide a platform for feedback from actors engaged with buildings in use for environmental designers to utilize in developing reflective design rationale to avoid adverse consequences in future designs or correct consequences in past and current designs. Since buildings constitute such a large part of the human environment, it's important to research the effects of buildings on their inhabitants. In order for environmental designers to act on feedback from situated use, designers need to have access to that feedback and all actors interacting with the building design need to have an easy, inexpensive, and accessible method to submit feedback. These needs can be addressed by utilizing modern networked and mobile computing to collect and access building feedback. The analysis presented in this dissertation is informed by a thorough evaluation of the theory of reflective practice, activity theory, environmental design, and cognitive science research. From this analysis, I developed the following contributions. First, I expanded Schon's reflective practice by combining his theory with a modified version of activity theory, using activity theory to enrich reflective practice and create Reflective Activity Systems Theory (RAST), which provides a new framework to develop design rationale based on feedback from use and a focus on the activity. Second, I suggest the design of an activity information system

  14. Metal-organic frameworks for the storage and delivery of biologically active hydrogen sulfide

    SciTech Connect

    Allan, Phoebe K; Wheatley, Paul S; Aldous, David; Mohideen, M Infas; Tang, Chiu; Hriljac, Joseph A; Megson, Ian L; Chapman, Karena W; De Weireld, Guy; Vaesen, Sebastian; Morris, Russell E

    2012-04-02

    Hydrogen sulfide is an extremely toxic gas that is also of great interest for biological applications when delivered in the correct amount and at the desired rate. Here we show that the highly porous metal-organic frameworks with the CPO-27 structure can bind the hydrogen sulfide relatively strongly, allowing the storage of the gas for at least several months. Delivered gas is biologically active in preliminary vasodilation studies of porcine arteries, and the structure of the hydrogen sulfide molecules inside the framework has been elucidated using a combination of powder X-ray diffraction and pair distribution function analysis.

  15. Systems theory and the ethics of human enhancement: a framework for NBIC convergence.

    PubMed

    Khushf, George

    2004-05-01

    Representatives from government and the private sector recommend a major, cooperative initiative directed toward using NBIC (nano-, bio-, info-, and cogno-) technologies for human enhancement. By appropriately seeding the convergence of NBIC domains, they believe that the rate of development can be both accelerated and simultaneously channeled to avoid adverse risk and advance human good. However, to accomplish these goals, leaders of the convergence efforts identified as a major intellectual barrier the "development of a hierarchical architecture for integrating science across many scales, disciplines, and data modalities." Such a holistic framework requires a radical rethinking of the nature of science and engineering, and, beyond this, is also necessary for addressing their normative ethical and societal implications. In the first part of this essay, I consider the claim that a new view of science and engineering is needed. After reviewing the central features of a classical view of science, I consider aspects of the nano-revolution, showing why the classical conception is inappropriate and how a systems-oriented perspective is responsive to the character of this new science. I then consider how both science and engineering are transformed, calling into question older dichotomies between pure and applied domains. With the reworking of this distinction comes opportunities for rethinking the relation between science and the humanities more generally, which is necessary if we are to more appropriately address normative ethical aspects of the convergence initiative. After providing this groundwork for the needed hierarchical architecture, I consider a useful example of how a systems perspective might guide NBIC convergence. In the 1960s-1990s George Engel advocated a systems-theoretic model as an alternative to a more reductionistic "biomedical model" in medicine, and he did it for the exact same reasons as those advocated by the leaders of the NBIC convergence

  16. Benchmarking density functional theory predictions of framework structures and properties in a chemically diverse test set of metal-organic frameworks

    DOE PAGESBeta

    Nazarian, Dalar; Ganesh, P.; Sholl, David S.

    2015-09-30

    We compiled a test set of chemically and topologically diverse Metal–Organic Frameworks (MOFs) with high accuracy experimentally derived crystallographic structure data. The test set was used to benchmark the performance of Density Functional Theory (DFT) functionals (M06L, PBE, PW91, PBE-D2, PBE-D3, and vdW-DF2) for predicting lattice parameters, unit cell volume, bonded parameters and pore descriptors. On average PBE-D2, PBE-D3, and vdW-DF2 predict more accurate structures, but all functionals predicted pore diameters within 0.5 Å of the experimental diameter for every MOF in the test set. The test set was also used to assess the variance in performance of DFT functionalsmore » for elastic properties and atomic partial charges. The DFT predicted elastic properties such as minimum shear modulus and Young's modulus can differ by an average of 3 and 9 GPa for rigid MOFs such as those in the test set. Moreover, we calculated the partial charges by vdW-DF2 deviate the most from other functionals while there is no significant difference between the partial charges calculated by M06L, PBE, PW91, PBE-D2 and PBE-D3 for the MOFs in the test set. We find that while there are differences in the magnitude of the properties predicted by the various functionals, these discrepancies are small compared to the accuracy necessary for most practical applications.« less

  17. Life course theory as a framework to examine becoming a mother of a medically fragile preterm infant.

    PubMed

    Black, Beth Perry; Holditch-Davis, Diane; Miles, Margaret S

    2009-02-01

    Life course theory, a sociological framework, was used to analyze the phenomenon of becoming a mother, with longitudinal narrative data from 34 women who gave birth prematurely after a high-risk pregnancy, and whose infant became medically fragile. Women faced challenges of mistimed birth and mothering a technologically dependent infant. Before social ties were established, legal and biological ties required mothers to make critical decisions about their infants. Liminality characterized mothers' early involvement with their infants. The mothers worked to know, love, and establish deeper attachments to this baby. The infant's homecoming was a key turning point; it decreased liminality of early mothering, increased mothers' control of infants' care, and gave them time and place to know their infants more intimately. PMID:18726937

  18. An information theory based framework for the measurement of population health.

    PubMed

    Nesson, Erik T; Robinson, Joshua J

    2015-04-01

    This paper proposes a new framework for the measurement of population health and the ranking of the health of different geographies. Since population health is a latent variable, studies which measure and rank the health of different geographies must aggregate observable health attributes into one summary measure. We show that the methods used in nearly all the literature to date implicitly assume that all attributes are infinitely substitutable. Our method, based on the measurement of multidimensional welfare and inequality, minimizes the entropic distance between the summary measure of population health and the distribution of the underlying attributes. This summary function coincides with the constant elasticity of substitution and Cobb-Douglas production functions and naturally allows different assumptions regarding attribute substitutability or complementarity. To compare methodologies, we examine a well-known ranking of the population health of U.S. states, America's Health Rankings. We find that states' rankings are somewhat sensitive to changes in the weight given to each attribute, but very sensitive to changes in aggregation methodology. Our results have broad implications for well-known health rankings such as the 2000 World Health Report, as well as other measurements of population and individual health levels and the measurement and decomposition of health inequality. PMID:25792258

  19. General framework for transfer path analysis: History, theory and classification of techniques

    NASA Astrophysics Data System (ADS)

    van der Seijs, Maarten V.; de Klerk, Dennis; Rixen, Daniel J.

    2016-02-01

    Transfer Path Analysis (TPA) designates the family of test-based methodologies to study the transmission of mechanical vibrations. Since the first adaptation of electric network analogies in the field of mechanical engineering a century ago, a multitude of TPA methods have emerged and found their way into industrial development processes. Nowadays the TPA paradigm is largely commercialised into out-of-the-box testing products, making it difficult to articulate the differences and underlying concepts that are paramount to understanding the vibration transmission problem. The aim of this paper is to derive and review a wide repertoire of TPA techniques from their conceptual basics, liberating them from their typical field of application. A selection of historical references is provided to align methodological developments with particular milestones in science. Eleven variants of TPA are derived from a unified framework and classified into three categories, namely classical, component-based and transmissibility-based TPA. Current challenges and practical aspects are discussed and reference is made to related fields of research.

  20. Knowing Inquiry as Practice and Theory: Developing a Pedagogical Framework with Elementary School Teachers

    NASA Astrophysics Data System (ADS)

    Poon, Chew-Leng; Lee, Yew-Jin; Tan, Aik-Ling; Lim, Shirley S. L.

    2012-04-01

    In this paper, we characterize the inquiry practices of four elementary school teachers by means of a pedagogical framework. Our study revealed core components of inquiry found in theoretically-driven models as well as practices that were regarded as integral to the success of day-to-day science teaching in Singapore. This approach towards describing actual science inquiry practices—a surprisingly neglected area—uncovered nuances in teacher instructions that can impact inquiry-based lessons as well as contribute to a practice-oriented perspective of science teaching. In particular, we found that these teachers attached importance to (a) preparing students for investigations, both cognitively and procedurally; (b) iterating pedagogical components where helping students understand and construct concepts did not follow a planned linear path but involved continuous monitoring of learning; and (c) synthesizing concepts in a consolidation phase. Our findings underscore the dialectical relationship between practice-oriented knowledge and theoretical conceptions of teaching/learning thereby helping educators better appreciate how teachers adapt inquiry science for different contexts.

  1. Coupled metal partitioning dynamics and toxicodynamics at biointerfaces: a theory beyond the biotic ligand model framework.

    PubMed

    Duval, Jérôme F L

    2016-04-14

    A mechanistic understanding of the processes governing metal toxicity to microorganisms (bacteria, algae) calls for an adequate formulation of metal partitioning at biointerfaces during cell exposure. This includes the account of metal transport dynamics from bulk solution to biomembrane and the kinetics of metal internalisation, both potentially controlling the intracellular and surface metal fractions that originate cell growth inhibition. A theoretical rationale is developed here for such coupled toxicodynamics and interfacial metal partitioning dynamics under non-complexing medium conditions with integration of the defining cell electrostatic properties. The formalism explicitly considers intertwined metal adsorption at the biointerface, intracellular metal excretion, cell growth and metal depletion from bulk solution. The theory is derived under relevant steady-state metal transport conditions on the basis of coupled Nernst-Planck equation and continuous logistic equation modified to include metal-induced cell growth inhibition and cell size changes. Computational examples are discussed to identify limitations of the classical Biotic Ligand Model (BLM) in evaluating metal toxicity over time. In particular, BLM is shown to severely underestimate metal toxicity depending on cell exposure time, metal internalisation kinetics, cell surface electrostatics and initial cell density. Analytical expressions are provided for the interfacial metal concentration profiles in the limit where cell-growth is completely inhibited. A rigorous relationship between time-dependent cell density and metal concentrations at the biosurface and in bulk solution is further provided, which unifies previous equations formulated by Best and Duval under constant cell density and cell size conditions. The theory is sufficiently flexible to adapt to toxicity scenarios with involved cell survival-death processes. PMID:26980542

  2. Applying Probability Theory for the Quality Assessment of a Wildfire Spread Prediction Framework Based on Genetic Algorithms

    PubMed Central

    Cencerrado, Andrés; Cortés, Ana; Margalef, Tomàs

    2013-01-01

    This work presents a framework for assessing how the existing constraints at the time of attending an ongoing forest fire affect simulation results, both in terms of quality (accuracy) obtained and the time needed to make a decision. In the wildfire spread simulation and prediction area, it is essential to properly exploit the computational power offered by new computing advances. For this purpose, we rely on a two-stage prediction process to enhance the quality of traditional predictions, taking advantage of parallel computing. This strategy is based on an adjustment stage which is carried out by a well-known evolutionary technique: Genetic Algorithms. The core of this framework is evaluated according to the probability theory principles. Thus, a strong statistical study is presented and oriented towards the characterization of such an adjustment technique in order to help the operation managers deal with the two aspects previously mentioned: time and quality. The experimental work in this paper is based on a region in Spain which is one of the most prone to forest fires: El Cap de Creus. PMID:24453898

  3. Developing an integrated biomedical and behavioural theory of functioning and disability: adding models of behaviour to the ICF framework.

    PubMed

    Johnston, Marie; Dixon, Diane

    2014-01-01

    The International Classification of Functioning Disability and Health (ICF) offers an agreed language on which a scientific model of functional outcomes can be built. The ICF defines functional outcomes as activity and activity limitations (AL) and defines both in behavioural terms. The ICF, therefore, appears to invite explanations of AL as behaviours. Studies of AL find that psychological variables, especially perceptions of control, add to biomedical variables in predicting AL. Therefore, two improved models are proposed, which integrate the ICF with two psychological theories, the theory of planned behaviour (TPB) and social cognitive theory (SCT). These models have a sound evidence base as good predictors of behaviour, include perceived control constructs and are compatible with existing evidence about AL. When directly tested in studies of community and clinic-based populations, both integrated models (ICF/TPB and ICF/SCT) outperform each of the three basic models (ICF, TPB and SCT). However, when predicting activity rather than AL, the biomedical model of the ICF does not improve prediction of activity by TPB and SCT on their own. It is concluded that these models offer a better explanation of functional outcomes than the ICF alone and could form the basis for the development of improved models. PMID:25211207

  4. Analyzing Activities in the Course of Science Education, According to Activity Theory: The Case of Sound

    ERIC Educational Resources Information Center

    Theodoraki, Xarikleia; Plakitsi, Katerina

    2013-01-01

    In the present study, we analyze activities on the topic of sound, which are performed in the science education laboratory lessons in the third-year students of the Department of Early Childhood Education at the University of Ioannina. The analysis of the activities is based on one of the most modern learning theories of CHAT (Cultural Historical…

  5. On the Design of Smart Homes: A Framework for Activity Recognition in Home Environment.

    PubMed

    Cicirelli, Franco; Fortino, Giancarlo; Giordano, Andrea; Guerrieri, Antonio; Spezzano, Giandomenico; Vinci, Andrea

    2016-09-01

    A smart home is a home environment enriched with sensing, actuation, communication and computation capabilities which permits to adapt it to inhabitants preferences and requirements. Establishing a proper strategy of actuation on the home environment can require complex computational tasks on the sensed data. This is the case of activity recognition, which consists in retrieving high-level knowledge about what occurs in the home environment and about the behaviour of the inhabitants. The inherent complexity of this application domain asks for tools able to properly support the design and implementation phases. This paper proposes a framework for the design and implementation of smart home applications focused on activity recognition in home environments. The framework mainly relies on the Cloud-assisted Agent-based Smart home Environment (CASE) architecture offering basic abstraction entities which easily allow to design and implement Smart Home applications. CASE is a three layered architecture which exploits the distributed multi-agent paradigm and the cloud technology for offering analytics services. Details about how to implement activity recognition onto the CASE architecture are supplied focusing on the low-level technological issues as well as the algorithms and the methodologies useful for the activity recognition. The effectiveness of the framework is shown through a case study consisting of a daily activity recognition of a person in a home environment. PMID:27468841

  6. Improving condition severity classification with an efficient active learning based framework.

    PubMed

    Nissim, Nir; Boland, Mary Regina; Tatonetti, Nicholas P; Elovici, Yuval; Hripcsak, George; Shahar, Yuval; Moskovitch, Robert

    2016-06-01

    Classification of condition severity can be useful for discriminating among sets of conditions or phenotypes, for example when prioritizing patient care or for other healthcare purposes. Electronic Health Records (EHRs) represent a rich source of labeled information that can be harnessed for severity classification. The labeling of EHRs is expensive and in many cases requires employing professionals with high level of expertise. In this study, we demonstrate the use of Active Learning (AL) techniques to decrease expert labeling efforts. We employ three AL methods and demonstrate their ability to reduce labeling efforts while effectively discriminating condition severity. We incorporate three AL methods into a new framework based on the original CAESAR (Classification Approach for Extracting Severity Automatically from Electronic Health Records) framework to create the Active Learning Enhancement framework (CAESAR-ALE). We applied CAESAR-ALE to a dataset containing 516 conditions of varying severity levels that were manually labeled by seven experts. Our dataset, called the "CAESAR dataset," was created from the medical records of 1.9 million patients treated at Columbia University Medical Center (CUMC). All three AL methods decreased labelers' efforts compared to the learning methods applied by the original CAESER framework in which the classifier was trained on the entire set of conditions; depending on the AL strategy used in the current study, the reduction ranged from 48% to 64% that can result in significant savings, both in time and money. As for the PPV (precision) measure, CAESAR-ALE achieved more than 13% absolute improvement in the predictive capabilities of the framework when classifying conditions as severe. These results demonstrate the potential of AL methods to decrease the labeling efforts of medical experts, while increasing accuracy given the same (or even a smaller) number of acquired conditions. We also demonstrated that the methods included in

  7. A unified framework for activity recognition-based behavior analysis and action prediction in smart homes.

    PubMed

    Fatima, Iram; Fahim, Muhammad; Lee, Young-Koo; Lee, Sungyoung

    2013-01-01

    In recent years, activity recognition in smart homes is an active research area due to its applicability in many applications, such as assistive living and healthcare. Besides activity recognition, the information collected from smart homes has great potential for other application domains like lifestyle analysis, security and surveillance, and interaction monitoring. Therefore, discovery of users common behaviors and prediction of future actions from past behaviors become an important step towards allowing an environment to provide personalized service. In this paper, we develop a unified framework for activity recognition-based behavior analysis and action prediction. For this purpose, first we propose kernel fusion method for accurate activity recognition and then identify the significant sequential behaviors of inhabitants from recognized activities of their daily routines. Moreover, behaviors patterns are further utilized to predict the future actions from past activities. To evaluate the proposed framework, we performed experiments on two real datasets. The results show a remarkable improvement of 13.82% in the accuracy on average of recognized activities along with the extraction of significant behavioral patterns and precise activity predictions with 6.76% increase in F-measure. All this collectively help in understanding the users" actions to gain knowledge about their habits and preferences. PMID:23435057

  8. A Unified Framework for Activity Recognition-Based Behavior Analysis and Action Prediction in Smart Homes

    PubMed Central

    Fatima, Iram; Fahim, Muhammad; Lee, Young-Koo; Lee, Sungyoung

    2013-01-01

    In recent years, activity recognition in smart homes is an active research area due to its applicability in many applications, such as assistive living and healthcare. Besides activity recognition, the information collected from smart homes has great potential for other application domains like lifestyle analysis, security and surveillance, and interaction monitoring. Therefore, discovery of users common behaviors and prediction of future actions from past behaviors become an important step towards allowing an environment to provide personalized service. In this paper, we develop a unified framework for activity recognition-based behavior analysis and action prediction. For this purpose, first we propose kernel fusion method for accurate activity recognition and then identify the significant sequential behaviors of inhabitants from recognized activities of their daily routines. Moreover, behaviors patterns are further utilized to predict the future actions from past activities. To evaluate the proposed framework, we performed experiments on two real datasets. The results show a remarkable improvement of 13.82% in the accuracy on average of recognized activities along with the extraction of significant behavioral patterns and precise activity predictions with 6.76% increase in F-measure. All this collectively help in understanding the users” actions to gain knowledge about their habits and preferences. PMID:23435057

  9. Cultural-Historical Activity Theory and Domain Analysis: Metatheoretical Implications for Information Science

    ERIC Educational Resources Information Center

    Wang, Lin

    2013-01-01

    Background: Cultural-historical activity theory is an important theory in modern psychology. In recent years, it has drawn more attention from related disciplines including information science. Argument: This paper argues that activity theory and domain analysis which uses the theory as one of its bases could bring about some important…

  10. Perceptions of Asian American men about tobacco cigarette consumption: a social learning theory framework.

    PubMed

    Spigner, Clarence; Shigaki, Alison; Tu, Shin-Ping

    2005-10-01

    Little information exists regarding the perceptions that ethnic-specific groups of Asian American men have about tobacco cigarette smoking. Thirty Asian American men of immigrant status living in Seattle, Washington, were stratified by ethnicity (Chinese and Vietnamese), language (Mandarin, Cantonese, Vietnamese) and age to comprise six focus groups (two Mandarin speaking men aged 20-40 years and 10 aged 41-65+ years; three Cantonese men aged 20-40 years and another six aged 41-65+ years; four Vietnamese men aged 20-40 years and another five aged 41-65+ years). All group interviews were audio-taped and six separate hard-copy transcripts were produced, independently theme-coded by three investigators to ensure inter-rater reliability, and analyzed with QRS NUD*IST ethnographic software. Bandura (1969, 1986) categorized emergent contextual themes within the constructs of "predisposing, enabling, and reinforcing" behavioral determinants from Social Learning Theory. Smoking to be sociable emerged as the most salient theme. Awareness of tobacco-related diseases other than lung cancer was less evident, as was a self-perceived lack of will-power to quit. Concerns about side-stream smoking affecting family members, along with smoking to alleviate stress, were key findings. Further tobacco-related research is needed that incorporates considerations for cultural dynamics. PMID:19813295

  11. Predictors of Prosthodontic Treatment-Related Behavior Using the Theory of Planned Behavior Framework.

    PubMed

    Vieira, Antonio Helio; Castro e Silva, Donizete; Nogueira, Túlio Eduardo; Leles, Cláudio Rodrigues

    2016-01-01

    The Theory of Planned Behavior (TPB) was used to assess subjects' intentions and behavior to predict willingness to undergo prosthodontic care. A questionnaire was administered to 225 adults with history of teeth loss who currently were not under prosthodontic treatment. The questionnaire comprised TPB components (attitude toward behaviour [ATB], subjective norm [SN], and perceived behavioral control [PBC]) containing items with potential influence on the intentions and behavior of individuals toward prosthodontic care. Clinical and socioeconomic data were also assessed. A path regression model was constructed explaining two dependent variables simultaneously: one explained the influence of PBC on intention (R2=0.04) and another explained the influence of dental arch, position of lost teeth, socioeconomic status, and PBC on behavior (R2=0.31). It was concluded that PBC was a relevant TPB component that encompasses perception of costs, opportunity cost, perceived need, and access to dental care. Clinical and socioeconomic factors were also major determinants of behavior toward prosthodontic treatment. PMID:26929951

  12. Nuclear response theory for spin-isospin excitations in a relativistic quasiparticle-phonon coupling framework

    NASA Astrophysics Data System (ADS)

    Robin, Caroline; Litvinova, Elena

    2016-07-01

    A new theoretical approach to spin-isospin excitations in open-shell nuclei is presented. The developed method is based on the relativistic meson-exchange nuclear Lagrangian of Quantum Hadrodynamics and extends the response theory for superfluid nuclear systems beyond relativistic quasiparticle random phase approximation in the proton-neutron channel (pn-RQRPA). The coupling between quasiparticle degrees of freedom and collective vibrations (phonons) introduces a time-dependent effective interaction, in addition to the exchange of pion and ρ -meson taken into account without retardation. The time-dependent contributions are treated in the resonant time-blocking approximation, in analogy to the previously developed relativistic quasiparticle time-blocking approximation (RQTBA) in the neutral (non-isospin-flip) channel. The new method is called proton-neutron RQTBA (pn-RQTBA) and is applied to the Gamow-Teller resonance in a chain of neutron-rich nickel isotopes 68-78Ni . A strong fragmentation of the resonance along with quenching of the strength, as compared to pn-RQRPA, is obtained. Based on the calculated strength distribution, beta-decay half-lives of the considered isotopes are computed and compared to pn-RQRPA half-lives and to experimental data. It is shown that a considerable improvement of the half-life description is obtained in pn-RQTBA because of the spreading effects, which bring the lifetimes to a very good quantitative agreement with data.

  13. A new framework for intrusion detection based on rough set theory

    NASA Astrophysics Data System (ADS)

    Li, Zhijun; Wu, Yu; Wang, Guoyin; Hai, Yongjun; He, Yunpeng

    2004-04-01

    Intrusion detection is an essential component of critical infrastructure protection mechanism. Since many current IDSs are constructed by manual encoding of expert knowledge, it is time-consuming to update their knowledge. In order to solve this problem, an effective method for misuse intrusion detection with low cost and high efficiency is presented. This paper gives an overview of our research in building a detection model for identifying known intrusions, their variations and novel attacks with unknown natures. The method is based on rough set theory and capable of extracting a set of detection rules from network packet features. After getting a decision table through preprocessing raw packet data, rough-set-based reduction and rule generation algorithms are applied, and useful rules for intrusion detection are obtained. In addition, a rough set and rule-tree-based incremental knowledge acquisition algorithm is presented in order to solve problems of updating rule set when new attacks appear. Compared with other methods, our method requires a smaller size of training data set and less effort to collect training data. Experimental results demonstrate that our system is effective and more suitable for online intrusion detection.

  14. Characteristics of traffic flow at a non-signalized intersection in the framework of game theory

    NASA Astrophysics Data System (ADS)

    Fan, Hongqiang; Jia, Bin; Tian, Junfang; Yun, Lifen

    2014-12-01

    At a non-signalized intersection, some vehicles violate the traffic rules to pass the intersection as soon as possible. These behaviors may cause many traffic conflicts even traffic accidents. In this paper, a simulation model is proposed to research the effects of these behaviors at a non-signalized intersection. Vehicle’s movement is simulated by the cellular automaton (CA) model. The game theory is introduced for simulating the intersection dynamics. Two types of driver participate the game process: cooperator (C) and defector (D). The cooperator obey the traffic rules, but the defector does not. A transition process may occur when the cooperator is waiting before the intersection. The critical value of waiting time follows the Weibull distribution. One transition regime is found in the phase diagram. The simulation results illustrate the applicability of the proposed model and reveal a number of interesting insights into the intersection management, including that the existence of defectors is benefit for the capacity of intersection, but also reduce the safety of intersection.

  15. Contributions of Attachment Theory and Research: A Framework for Future Research, Translation, and Policy

    PubMed Central

    Cassidy, Jude; Jones, Jason D.; Shaver, Phillip R.

    2014-01-01

    Attachment theory has been generating creative and impactful research for almost half a century. In this article we focus on the documented antecedents and consequences of individual differences in infant attachment patterns, suggesting topics for further theoretical clarification, research, clinical interventions, and policy applications. We pay particular attention to the concept of cognitive “working models” and to neural and physiological mechanisms through which early attachment experiences contribute to later functioning. We consider adult caregiving behavior that predicts infant attachment patterns, and the still-mysterious “transmission gap” between parental AAI classifications and infant Strange Situation classifications. We also review connections between attachment and (a) child psychopathology, (b) neurobiology, (c) health and immune function, (d) empathy, compassion, and altruism, (e) school readiness, and (f) culture. We conclude with clinical-translational and public policy applications of attachment research that could reduce the occurrence and maintenance of insecure attachment during infancy and beyond. Our goal is to inspire researchers to continue advancing the field by finding new ways to tackle long-standing questions and by generating and testing novel hypotheses. PMID:24342848

  16. Theory of Activated Relaxation in Nanoscale Confined Liquids

    NASA Astrophysics Data System (ADS)

    Mirigian, Stephen; Schweizer, Kenneth

    2014-03-01

    We extend the recently developed Elastically Cooperative Nonlinear Langevin Equation(ECNLE) theory of activated relaxation in supercooled liquids to treat the case of geometrically confined liquids. Generically, confinement of supercooled liquids leads to a speeding up of the dynamics(with a consequent depression of the glass transition temperature) extending on the order of tens of molecular diameters away from a free surface. At present, this behavior is not theoretically well understood. Our theory interprets the speed up in dynamics in terms of two coupled effects. First, a direct surface effect, extending two to three molecular diameters from a free surface, and related to a local rearrangement of molecules with a single cage. The second is a longer ranged ``confinement'' effect, extending tens of molecular diameters from a free surface and related to the long range elastic penalty necessary for a local rearrangement. The theory allows for the calculation of relaxation time and Tg profiles within a given geometry and first principles calculations of relevant length scales. Comparison to both dynamic and pseudo-thermodynamic measurements shows reasonable agreement to experiment with no adjustable parameters.

  17. Framework of Consciousness from Semblance of Activity at Functionally LINKed Postsynaptic Membranes

    PubMed Central

    Vadakkan, Kunjumon I.

    2010-01-01

    Consciousness is seen as a difficult “binding” problem. Binding, a process where different sensations evoked by an item are associated in the nervous system, can be viewed as a process similar to associative learning. Several reports that consciousness is associated with some form of memory imply that different forms of memories have a common feature contributing to consciousness. Based on a proposed synaptic mechanism capable of explaining different forms of memory, we developed a framework for consciousness. It is based on the formation of semblance of sensory stimulus from (1) synaptic semblances when excitatory postsynaptic potentials arrive at functionally LINKed postsynaptic membranes, and (2) network semblances when these potentials summate to elicit action potential initiating activity in a network of neurons. It is then possible to derive a framework for consciousness as a multi-dimensional semblance. According to this framework, a continuum of semblances formed from background sensory stimuli and oscillating neuronal activities serve to maintain consciousness. Feasibility of this framework to explain various physiological and pathological states of consciousness, its subjective nature and qualia is examined. PMID:21833231

  18. Insights from Skill Acquisition Theory for Grammar Activity Sequencing and Design in Foreign Language Teaching

    ERIC Educational Resources Information Center

    Criado, Raquel

    2016-01-01

    This article presents a framework for the elaboration of Foreign Language Teaching (FLT) grammar materials for adults based on the application to SLA of Skill Acquisition Theory (SAT). This theory is argued to compensate for the major drawbacks of FLT settings in comparison with second language contexts (lack of classroom learning time and limited…

  19. Testing Punctuated Equilibrium Theory Using Evolutionary Activity Statistics

    NASA Astrophysics Data System (ADS)

    Woodberry, O. G.; Korb, K. B.; Nicholson, A. E.

    The Punctuated Equilibrium hypothesis (Eldredge and Gould,1972) asserts that most evolutionary change occurs during geologically rapid speciation events, with species exhibiting stasis most of the time. Punctuated Equilibrium is a natural extension of Mayr's theories on peripatric speciation via the founder effect, (Mayr, 1963; Eldredge and Gould, 1972) which associates changes in diversity to a population bottleneck. That is, while the formation of a foundation bottleneck brings an initial loss of genetic variation, it may subsequently result in the emergence of a child species distinctly different from its parent species. In this paper we adapt Bedau's evolutionary activity statistics (Bedau and Packard, 1991) to test these effects in an ALife simulation of speciation. We find a relative increase in evolutionary activity during speciations events, indicating that punctuation is occurring.

  20. The theory of an active magnetic regenerative refrigerator

    NASA Technical Reports Server (NTRS)

    Barclay, J. A.

    1983-01-01

    The adiabatic temperature change with field which is limited to about 2 K/Tesla for ferromagnets near their Curie temperatures by the change of magnetization with temperature and the lattice heat capacity is discussed. Practical magnetic refrigerators operate on a regenerative cycle such as the Brayton cycle. This cycle can be executed through the use of an active magnetic regenerator, i.e., a regenerator composed of magnetic material that is cycled in an out of a magnetic field with appropriate fluid flows. The theory of these devices is predicted by solving the partial differential equations that describe fluid and the magnetic solid. The active magnetic regenerator is described along with the method of calculation. Temperature profiles for a normal regenerator and a magnetic regenerative refrigerator are shown.

  1. A Gaussian process framework for modelling stellar activity signals in radial velocity data

    NASA Astrophysics Data System (ADS)

    Rajpaul, V.; Aigrain, S.; Osborne, M. A.; Reece, S.; Roberts, S.

    2015-09-01

    To date, the radial velocity (RV) method has been one of the most productive techniques for detecting and confirming extrasolar planetary candidates. Unfortunately, stellar activity can induce RV variations which can drown out or even mimic planetary signals - and it is notoriously difficult to model and thus mitigate the effects of these activity-induced nuisance signals. This is expected to be a major obstacle to using next-generation spectrographs to detect lower mass planets, planets with longer periods, and planets around more active stars. Enter Gaussian processes (GPs) which, we note, have a number of attractive features that make them very well suited to disentangling stellar activity signals from planetary signals. We present here a GP framework we developed to model RV time series jointly with ancillary activity indicators (e.g. bisector velocity spans, line widths, chromospheric activity indices), allowing the activity component of RV time series to be constrained and disentangled from e.g. planetary components. We discuss the mathematical details of our GP framework, and present results illustrating its encouraging performance on both synthetic and real RV data sets, including the publicly available Alpha Centauri B data set.

  2. Minimal continuum theories of structure formation in dense active fluids

    NASA Astrophysics Data System (ADS)

    Dunkel, Jörn; Heidenreich, Sebastian; Bär, Markus; Goldstein, Raymond E.

    2013-04-01

    Self-sustained dynamical phases of living matter can exhibit remarkable similarities over a wide range of scales, from mesoscopic vortex structures in microbial suspensions and motility assays of biopolymers to turbulent large-scale instabilities in flocks of birds or schools of fish. Here, we argue that, in many cases, the phenomenology of such active states can be efficiently described in terms of fourth- and higher-order partial differential equations. Structural transitions in these models can be interpreted as Landau-type kinematic transitions in Fourier (wavenumber) space, suggesting that microscopically different biological systems can share universal long-wavelength features. This general idea is illustrated through numerical simulations for two classes of continuum models for incompressible active fluids: a Swift-Hohenberg-type scalar field theory, and a minimal vector model that extends the classical Toner-Tu theory and appears to be a promising candidate for the quantitative description of dense bacterial suspensions. We discuss how microscopic symmetry-breaking mechanisms can enter macroscopic continuum descriptions of collective microbial motion near surfaces, and conclude by outlining future applications.

  3. A Biomimetic Propulsor for Active Noise Control. Part 2: Theory

    NASA Astrophysics Data System (ADS)

    Annaswamy Krol, A., Jr.; Bandyopadhyay, P. R.

    2000-11-01

    The alteration of radiated noise in underwater propulsors using biomimetic active control is considered. Wake momentum filling is carried out by introducing artificial muscles at the trailing edge of a stator blade of an upstream stator propulsor, and articulating them like a fish tail (see companion abstract Part 1). Using a systems framework, we derive a methodology for the articulation of the muscles with active control. The unsteady force produced on the rotor because of velocity perturbations due to actuator displacements, wake deficits caused by stator boundary layers, and blade rotation is modeled. Linear and adaptive nonlinear control strategies are described for articulating the tail using unsteady force measurements. This active control procedure can be viewed as the realization of “virtual” blades with different sweep and noise characteristics and can affect the noise spectrum due to direct radiation significantly. The work provides an understanding of the effect of nonuniform wakes on radiated noise and can lead to a general approach by which wakes can be altered.

  4. Predicting physical activity and outcome expectations in cancer survivors: an application of Self-Determination Theory.

    PubMed

    Wilson, Philip M; Blanchard, Chris M; Nehl, Eric; Baker, Frank

    2006-07-01

    The purpose of this study was to examine the contributions of autonomous and controlled motives drawn from Self-Determination Theory (SDT; Intrinsic Motivation and Self-determination in Human Behavior. Plenum Press: New York, 1985; Handbook of Self-determination Research. University of Rochester Press: New York, 2002) towards predicting physical activity behaviours and outcome expectations in adult cancer survivors. Participants were cancer-survivors (N=220) and a non-cancer comparison cohort (N=220) who completed an adapted version of the Treatment Self-Regulation Questionnaire modified for physical activity behaviour (TSRQ-PA), an assessment of the number of minutes engaged in moderate-to-vigorous physical activity (MVPA) weekly, and the anticipated outcomes expected from regular physical activity (OE). Simultaneous multiple regression analyses indicated that autonomous motives was the dominant predictor of OEs across both cancer and non-cancer cohorts (R(2adj)=0.29-0.43), while MVPA was predicted by autonomous (beta's ranged from 0.21 to 0.34) and controlled (beta's ranged from -0.04 to -0.23) motives after controlling for demographic considerations. Cancer status (cancer versus no cancer) did not moderate the motivation-physical activity relationship. Collectively, these findings suggest that the distinction between autonomous and controlled motives is useful and compliments a growing body of evidence supporting SDT as a framework for understanding motivational processes in physical activity contexts with cancer survivors. PMID:16304621

  5. Promoting physical activity: development and testing of self-determination theory-based interventions

    PubMed Central

    2012-01-01

    A growing number of studies have pulled from Deci and Ryan's Self-Determination Theory to design interventions targeting health behavior change. More recently, researchers have begun using SDT to promote the adoption and maintenance of an active lifestyle. In this review, we aim to highlight how researchers and practitioners can draw from the SDT framework to develop, implement, and evaluate intervention efforts centered on increasing physical activity levels in different contexts and different populations. In the present paper, the rationale for using SDT to foster physical activity engagement is briefly reviewed before particular attention is given to three recent randomized controlled trials, the Canadian Physical Activity Counseling (PAC) Trial, the Empower trial from the UK, and the Portuguese PESO (Promotion of Health and Exercise in Obesity) trial, each of which focused on promoting physical activity behavior. The SDT-based intervention components, procedures, and participants are highlighted, and the key findings that have emanated from these three trials are presented. Lastly, we outline some of the limitations of the work conducted to date in this area and we acknowledge the challenges that arise when attempting to design, deliver, and test SDT-grounded interventions in the context of physical activity promotion. PMID:22385751

  6. Robust Muscle Activity Onset Detection Using an Unsupervised Electromyogram Learning Framework

    PubMed Central

    Liu, Jie; Ying, Dongwen; Rymer, William Z.; Zhou, Ping

    2015-01-01

    Accurate muscle activity onset detection is an essential prerequisite for many applications of surface electromyogram (EMG). This study presents an unsupervised EMG learning framework based on a sequential Gaussian mixture model (GMM) to detect muscle activity onsets. The distribution of the logarithmic power of EMG signal was characterized by a two-component GMM in each frequency band, in which the two components respectively correspond to the posterior distribution of EMG burst and non-burst logarithmic powers. The parameter set of the GMM was sequentially estimated based on maximum likelihood, subject to constraints derived from the relationship between EMG burst and non-burst distributions. An optimal threshold for EMG burst/non-burst classification was determined using the GMM at each frequency band, and the final decision was obtained by a voting procedure. The proposed novel framework was applied to simulated and experimental surface EMG signals for muscle activity onset detection. Compared with conventional approaches, it demonstrated robust performance for low and changing signal to noise ratios in a dynamic environment. The framework is applicable for real-time implementation, and does not require the assumption of non EMG burst in the initial stage. Such features facilitate its practical application. PMID:26038820

  7. Predictive Framework and Experimental Tests of the Kinetic Isotope Effect at Redox-Active Interfaces

    NASA Astrophysics Data System (ADS)

    Kavner, A.; John, S.; Black, J. R.

    2013-12-01

    Electrochemical reactions provide a compelling framework to study kinetic isotope effects because redox-related processes are important for a wide variety of geological and environmental processes. In the laboratory, electrochemical reaction rates can be electronically controlled and measured in the laboratory using a potentiostat. This enables variation of redox reactions rates independent of changes in chemistry and, and the resulting isotope compositions of reactants and products can be separated and analyzed. In the past years, a series of experimental studies have demonstrated a large, light, and tunable kinetic isotope effect during electrodeposition of metal Fe, Zn, Li, Cu, and Mo from a variety of solutions (e.g. Black et al., 2009, 2010, 2011). A theoretical framework based on Marcus kinetic theory predicts a voltage-dependent kinetic isotope effect (Kavner et al., 2005, 2008), however while this framework was able to predict the tunable nature of the effect, it was not able to simultaneously predict absolute reaction rates and relative isotope rates. Here we present a more complete development of a statistical mechanical framework for simple interfacial redox reactions, which includes isotopic behavior. The framework is able to predict a kinetic isotope effect as a function of temperature and reaction rate, starting with three input parameters: a single reorganization energy which describes the overall kinetics of the electron transfer reaction, and the equilibrium reduced partition function ratios for heavy and light isotopes in the product and reactant phases. We show the framework, elucidate some of the predictions, and show direct comparisons against isotope fractionation data obtained during laboratory and natural environment redox processes. A. Kavner, A. Shahar, F. Bonet, J. Simon and E. Young (2005) Geochim. Cosmochim. Acta, 69(12), 2971-2979. A. Kavner, S. G. John, S. Sass, and E. A. Boyle (2008), Geochim. Cosmochim. Acta, vol 72, pp. 1731

  8. Electroencephalograms in epilepsy: analysis and seizure prediction within the framework of Lyapunov theory

    NASA Astrophysics Data System (ADS)

    Moser, H. R.; Weber, B.; Wieser, H. G.; Meier, P. F.

    1999-06-01

    Epileptic seizures are defined as the clinical manifestation of excessive and hypersynchronous activity of neurons in the cerebral cortex and represent one of the most frequent malfunctions of the human central nervous system. Therefore, the search for precursors and predictors of a seizure is of utmost clinical relevance and may even guide us to a deeper understanding of the seizure generating mechanisms. We extract chaos-indicators such as Lyapunov exponents and Kolmogorov entropies from different types of electroencephalograms (EEGs): this covers mainly intracranial EEGs (semi-invasive and invasive recording techniques), but also scalp-EEGs from the surface of the skin. Among the analytical methods we tested up to now, we find that the spectral density of the local expansion exponents is best suited to predict the onset of a forthcoming seizure. We also evaluate the time-evolution of the dissipation in these signals: it exhibits strongly significant variations that clearly relate to the time relative to a seizure onset. This article is mainly devoted to an assessment of these methods with respect to their sensitivity to EEG changes, e.g., prior to a seizure. Further, we investigate interictal EEGs (i.e., far away from a seizure) in order to characterize their more general properties, such as the convergence of the reconstructed quantities with respect to the number of phase space dimensions. Generally we use multichannel reconstruction, but we also present a comparison with the delay-embedding technique.

  9. Decision-making framework for the application of in-situ activated carbon amendment to sediment.

    PubMed

    Choi, Yongju; Cho, Yeo-Myoung; Gala, William R; Hoelen, Thomas P; Werner, David; Luthy, Richard G

    2016-04-01

    This study provides a decision-support framework and a design methodology for preliminary evaluation of field application of in-situ activated carbon (AC) amendment to sediment to control the (bio)availability of hydrophobic organic contaminants. The decision-making framework comprises four sequential steps: screening assessment, input parameter determination, model prediction, and evaluation for process optimization. The framework allows the application of state-of-the-art experimental and modeling techniques to assess the effectiveness of the treatment under different field conditions and is designed for application as a part of a feasibility study. Through a stepwise process it is possible to assess the effectiveness of in-situ AC amendment with a proper consideration of different site conditions and application scenarios possible in the field. The methodology incorporates the effect of various parameters on performance including: site-specific kinetic coefficients, varied AC dose and particle size, sediment and AC sorption parameters, and pore-water velocity. The modeling framework allows comparison of design alternatives for treatment optimization and estimation of long-term effectiveness over a period of 10-20 years under slow mass transfer in the field. PMID:26736169

  10. Towards a statistical mechanical theory of active fluids.

    PubMed

    Marini Bettolo Marconi, Umberto; Maggi, Claudio

    2015-12-01

    We present a stochastic description of a model of N mutually interacting active particles in the presence of external fields and characterize its steady state behavior in the absence of currents. To reproduce the effects of the experimentally observed persistence of the trajectories of the active particles we consider a Gaussian force having a non-vanishing correlation time τ, whose finiteness is a measure of the activity of the system. With these ingredients we show that it is possible to develop a statistical mechanical approach similar to the one employed in the study of equilibrium liquids and to obtain the explicit form of the many-particle distribution function by means of the multidimensional unified colored noise approximation. Such a distribution plays a role analogous to the Gibbs distribution in equilibrium statistical mechanics and provides complete information about the microscopic state of the system. From here we develop a method to determine the one- and two-particle distribution functions in the spirit of the Born-Green-Yvon (BGY) equations of equilibrium statistical mechanics. The resulting equations which contain extra-correlations induced by the activity allow us to determine the stationary density profiles in the presence of external fields, the pair correlations and the pressure of active fluids. In the low density regime we obtained the effective pair potential ϕ(r) acting between two isolated particles separated by a distance, r, showing the existence of an effective attraction between them induced by activity. Based on these results, in the second half of the paper we propose a mean field theory as an approach simpler than the BGY hierarchy and use it to derive a van der Waals expression of the equation of state. PMID:26387914

  11. Development of a conceptual framework for understanding financial barriers to care among patients with cardiovascular-related chronic disease: a protocol for a qualitative (grounded theory) study

    PubMed Central

    Campbell, David J.T.; Manns, Braden J.; Hemmelgarn, Brenda R.; Sanmartin, Claudia; King-Shier, Kathryn M.

    2016-01-01

    Background: Patients with cardiovascular-related chronic diseases may face financial barriers to accessing health care, even in Canada, where universal health care insurance is in place. No current theory or framework is adequate for understanding the impact of financial barriers to care on these patients or how they experience financial barriers. The overall objective of this study is to develop a framework for understanding the role of financial barriers to care in the lives of patients with cardiovascular-related chronic diseases and the impact of such barriers on their health. Methods: We will perform an inductive qualitative grounded theory study to develop a framework to understand the effect of financial barriers to care on patients with cardiovascular-related chronic diseases. We will use semistructured interviews (face-to-face and telephone) with a purposive sample of adult patients from Alberta with at least 1 of hypertension, diabetes, heart disease or stroke. We will analyze interview transcripts in triplicate using grounded theory coding techniques, including open, focused and axial coding, following the principle of constant comparison. Interviews and analysis will be done iteratively to theoretical saturation. Member checking will be used to enhance rigour. Interpretation: A comprehensive framework for understanding financial barriers to accessing health care is instrumental for both researchers and clinicians who care for patients with chronic diseases. Such a framework would enable a better understanding of patient behaviour and nonadherence to recommended medical therapies and lifestyle modifications. PMID:27398378

  12. From Activity to Learning: Using Cultural Historical Activity Theory to Model School Library Programmes and Practices

    ERIC Educational Resources Information Center

    Meyers, Eric M.

    2007-01-01

    Introduction: changes in educational policy and practice demand that we examine school library programmes from a new perspective. As a model that takes a developmental view of minds in context, Cultural Historical Activity Theory is particularly well suited to the study of school libraries and the learning that occurs therein. This paper focuses…

  13. An Empirical Development of Critical Value Factors (CVF) of Online Learning Activities: An Application of Activity Theory and Cognitive Value Theory

    ERIC Educational Resources Information Center

    Levy, Yair

    2008-01-01

    According to activity theory, activities are at the center of human behavior. Extensive attention has been given in literature to the success and effectiveness of online learning programs. Value theory suggests that human perceived value is a critical construct in investigating what is important to individuals. However, very limited attention has…

  14. A Grounded Theory Approach to the Development of a Framework for Researching Children's Decision-Making Skills within Design and Technology Education

    ERIC Educational Resources Information Center

    Mettas, Alexandros; Norman, Eddie

    2011-01-01

    This paper discusses the establishment of a framework for researching children's decision-making skills in design and technology education through taking a grounded theory approach. Three data sources were used: (1) analysis of available literature; (2) curriculum analysis and interviews with teachers concerning their practice in relation to their…

  15. Negotiating the Contested Terrain of Equity-Focused Change Efforts in Schools: Critical Race Theory as a Leadership Framework for Creating More Equitable Schools

    ERIC Educational Resources Information Center

    Pollack, Terry M.; Zirkel, Sabrina

    2013-01-01

    Educational leaders attempting to enact equity-focused change in their schools are frequently met with fierce opposition by politically powerful parents whose children are well served by the status quo. The purpose of this conceptual article is to: (a) explore the utility of "Critical Race Theory" as a framework for helping K-12 school…

  16. Educating toward Direct Democracy and Ecological Sustainability: Theory of Social Ecology as a Framework for Critical, Democratic, and Community-Based Education

    ERIC Educational Resources Information Center

    Holohan, Kevin J.

    2012-01-01

    The aim of this dissertation project was to explore and extrapolate the work of the left-libertarian social theorist, Murray Bookchin (1921-2006), paying particular attention to his theory of social ecology and to examine its implications for and use as a comprehensive philosophical/theoretical framework for alternative secondary education that…

  17. Space suit bioenergetics: framework and analysis of unsuited and suited activity.

    PubMed

    Carr, Christopher E; Newman, Dava J

    2007-11-01

    Metabolic costs limit the duration and intensity of extravehicular activity (EVA), an essential component of future human missions to the Moon and Mars. Energetics Framework: We present a framework for comparison of energetics data across and between studies. This framework, applied to locomotion, differentiates between muscle efficiency and energy recovery, two concepts often confused in the literature. The human run-walk transition in Earth gravity occurs at the point for which energy recovery is approximately the same for walking and running, suggesting a possible role for recovery in gait transitions. Muscular Energetics: Muscle physiology limits the overall efficiency by which chemical energy is converted through metabolism to useful work. Unsuited Locomotion: Walking and running use different methods of energy storage and release. These differences contribute to the relative changes in the metabolic cost of walking and running as gravity is varied, with the metabolic cost of locomoting at a given velocity changing in proportion to gravity for running and less than in proportion for walking. Space Suits: Major factors affecting the energetic cost of suited movement include suit pressurization, gravity, velocity, surface slope, and space suit configuration. Apollo lunar surface EVA traverse metabolic rates, while unexpectedly low, were higher than other activity categories. The Lunar Roving Vehicle facilitated even lower metabolic rates, thus longer duration EVAs. Muscles and tendons act like springs during running; similarly, longitudinal pressure forces in gas pressure space suits allow spring-like storage and release of energy when suits are self-supporting. PMID:18018432

  18. Role of colored noise in active dynamical theories

    NASA Astrophysics Data System (ADS)

    Kachan, Devin; Levine, Alex

    2015-03-01

    The noise driving many dynamical systems is temporally correlated, or colored. Biological motor proteins, for example, generate processive stresses in biopolymer networks, and it would be incorrect to model this forcing as uncorrelated white noise. To gain insight into the role of the noise spectrum, we study a phi⌃4 theory in the presence of active colored noise with renormalization group techniques. Using a frequency shell integration scheme, we perform an epsilon expansion around d =8 for power law noise of the form 1/f⌃2 and find frequency and wavevector dependent corrections to the transport coefficients. The power law noise assumption is, of course, an approximation: all physical processes possess a small frequency cutoff. We study the effect of this cutoff and find a change in scaling behavior as the system transitions from a power law divergent regime to one dominated by white noise.

  19. Theory of activated transport in bilayer quantum Hall systems.

    PubMed

    Roostaei, B; Mullen, K J; Fertig, H A; Simon, S H

    2008-07-25

    We analyze the transport properties of bilayer quantum Hall systems at total filling factor nu=1 in drag geometries as a function of interlayer bias, in the limit where the disorder is sufficiently strong to unbind meron-antimeron pairs, the charged topological defects of the system. We compute the typical energy barrier for these objects to cross incompressible regions within the disordered system using a Hartree-Fock approach, and show how this leads to multiple activation energies when the system is biased. We then demonstrate using a bosonic Chern-Simons theory that in drag geometries current in a single layer directly leads to forces on only two of the four types of merons, inducing dissipation only in the drive layer. Dissipation in the drag layer results from interactions among the merons, resulting in very different temperature dependences for the drag and drive layers, in qualitative agreement with experiment. PMID:18764355

  20. Theory of Activated Transport in Bilayer Quantum Hall Systems

    NASA Astrophysics Data System (ADS)

    Roostaei, Bahman; Fertig, Herbert; Mullen, Kieran; Simon, Steven

    2008-03-01

    We analyze the transport properties of bilayer quantum Hall systems at total filling factor ν= 1 in drag geometries as a function of interlayer bias, in the limit where the disorder is sufficiently strong to unbind meron-antimeron pairs, the charged topological defects of the system. We compute the typical energy barrier for these objects to cross incompressible regions within the disordered system using a Hartree-Fock approach, and show how this leads to multiple activation energies when the system is biased. We then demonstrate using a bosonic Chern- Simons theory that in drag geometries, current in a single layer directly leads to forces on only two of the four types of merons, inducing dissipation only in the drive layer. Dissipation in the drag layer results from interactions among the merons, resulting in very different temperature dependences for the drag and drive layers, in qualitative agreement with experiment. We conclude with predictions for future experiments.

  1. Theory of Activated Transport in Bilayer Quantum Hall Systems

    NASA Astrophysics Data System (ADS)

    Roostaei, B.; Mullen, K. J.; Fertig, H. A.; Simon, S. H.

    2008-07-01

    We analyze the transport properties of bilayer quantum Hall systems at total filling factor ν=1 in drag geometries as a function of interlayer bias, in the limit where the disorder is sufficiently strong to unbind meron-antimeron pairs, the charged topological defects of the system. We compute the typical energy barrier for these objects to cross incompressible regions within the disordered system using a Hartree-Fock approach, and show how this leads to multiple activation energies when the system is biased. We then demonstrate using a bosonic Chern-Simons theory that in drag geometries current in a single layer directly leads to forces on only two of the four types of merons, inducing dissipation only in the drive layer. Dissipation in the drag layer results from interactions among the merons, resulting in very different temperature dependences for the drag and drive layers, in qualitative agreement with experiment.

  2. Platinum nanoparticles encapsulated metal-organic frameworks for the electrochemical detection of telomerase activity.

    PubMed

    Ling, Pinghua; Lei, Jianping; Jia, Li; Ju, Huangxian

    2016-01-21

    A simple and rapid electrochemical sensor is constructed for the detection of telomerase activity based on the electrocatalysis of platinum nanoparticle (Pt NP) encapsulated metal-organic frameworks (MOFs), which are synthesized by one-pot encapsulation of Pt NPs into prototypal MOFs, UiO-66-NH2. Integrating with the efficient electrocatalysis of Pt@MOFs towards NaBH4 oxidation, this biosensor shows the wide dynamic correlation of telomerase activity from 5 × 10(2) to 10(7) HeLa cells mL(-1) and the telomerase activity in a single HeLa cell was calculated to be 2.0 × 10(-11) IU, providing a powerful platform for detecting telomerase activity. PMID:26612011

  3. Towards a differentiated understanding of active travel behaviour: Using social theory to explore everyday commuting

    PubMed Central

    Guell, C.; Panter, J.; Jones, N.R.; Ogilvie, D.

    2012-01-01

    Fostering physical activity is an established public health priority for the primary prevention of a variety of chronic diseases. One promising population approach is to seek to embed physical activity in everyday lives by promoting walking and cycling to and from work (‘active commuting’) as an alternative to driving. Predominantly quantitative epidemiological studies have investigated travel behaviours, their determinants and how they may be changed towards more active choices. This study aimed to depart from narrow behavioural approaches to travel and investigate the social context of commuting with qualitative social research methods. Within a social practice theory framework, we explored how people describe their commuting experiences and make commuting decisions, and how travel behaviour is embedded in and shaped by commuters' complex social worlds. Forty-nine semi-structured interviews and eighteen photo-elicitation interviews with accompanying field notes were conducted with a subset of the Commuting and Health in Cambridge study cohort, based in the UK. The findings are discussed in terms of three particularly pertinent facets of the commuting experience. Firstly, choice and decisions are shaped by the constantly changing and fluid nature of commuters' social worlds. Secondly, participants express ambiguities in relation to their reasoning, ambitions and identities as commuters. Finally, commuting needs to be understood as an embodied and emotional practice. With this in mind, we suggest that everyday decision-making in commuting requires the tactical negotiation of these complexities. This study can help to explain the limitations of more quantitative and static models and frameworks in predicting travel behaviour and identify future research directions. PMID:22486840

  4. Synchronizing Substrate Activation Rates in Multicomponent Reactions with Metal-Organic Framework Catalysts.

    PubMed

    Aguirre-Díaz, Lina María; Iglesias, Marta; Snejko, Natalia; Gutiérrez-Puebla, Enrique; Monge, M Ángeles

    2016-05-01

    A study on the influence of the cation coordination number, number of Lewis acid centers, concurrent existence of Lewis base sites, and structure topology on the catalytic activity of six new indium MOFs, has been carried out for multicomponent reactions (MCRs). The new indium polymeric frameworks, namely [In8 (OH)6 (popha)6 (H2 O)4 ]⋅3 H2 O (InPF-16), [In(popha)(2,2'-bipy)]⋅3 H2 O (InPF-17), [In3 (OH)3 (popha)2 (4,4'-bipy)]⋅4 H2 O (InPF-18), [In2 (popha)2 (4,4'-bipy)2 ]⋅3 H2 O (InPF-19), [In(OH)(Hpopha)]⋅0.5 (1,7-phen) (InPF-20), and [In(popha)(1,10-phen)]⋅4 H2 O (InPF-21) (InPF=indium polymeric framework, H3 popha=5-(4-carboxy-2-nitrophenoxy)isophthalic acid, phen=phenanthroline, bipy=bipyridine), have been hydrothermally obtained by using both conventional heating (CH) and microwave (MW) procedures. These indium frameworks show efficient Lewis acid behavior for the solvent-free cyanosilylation of carbonyl compounds, the one pot Passerini 3-component (P-3CR) and the Ugi 4-component (U-4CR) reactions. In addition, InPF-17 was found to be a highly reactive, recyclable, and environmentally benign catalyst, which allows the efficient synthesis of α-aminoacyl amides. The relationship between the Lewis base/acid active site and the catalytic performance is explained by the 2D seven-coordinated indium framework of the catalyst InPF-17. This study is an attempt to highlight the main structural and synthetic factors that have to be taken into account when planning a new, effective MOF-based heterogeneous catalyst for multicomponent reactions. PMID:27010759

  5. Emotion at Work: A Contribution to Third-Generation Cultural-Historical Activity Theory

    ERIC Educational Resources Information Center

    Roth, Wolff-Michael

    2007-01-01

    Second-generation cultural-historical activity theory, which drew its inspiration from Leont'ev's work, constituted an advance over Vygotsky's first-generation theory by explicitly articulating the dialectical relation between individual and collective. As part of an effort to develop third-generation-historical activity theory, I propose in this…

  6. An Overview of Cultural Historical Activity Theory (CHAT) Use in Classroom Research 2000 to 2009

    ERIC Educational Resources Information Center

    Nussbaumer, Doris

    2012-01-01

    Western educational researchers have eagerly accepted activity theory (AT) also known as cultural historical activity theory (CHAT) to collect and analyze data in rich description of complex situations. As this theory is applicable to a wide variety of disciplines, this review is limited to education and specifically to qualitative studies of…

  7. From theory to practice: making entrustable professional activities come to life in the context of milestones.

    PubMed

    Englander, Robert; Carraccio, Carol

    2014-10-01

    Entrustable professional activities (EPAs) are gaining traction across the globe as a practical way to teach and assess competencies in the clinical setting. Full-scale implementation, though, has only taken place in obstetrics-gynecology in the Netherlands and in psychiatry in Australia and New Zealand. As with any conceptual framework, implementation in different contexts will require adaptations. For example, implementation in the United States will need to incorporate the Accreditation Council for Graduate Medical Education's competencies and the recently completed milestones for each of the specialties. In this issue, an article by Aylward and colleagues describes the process for implementing a handoff communication EPA, using milestones as the basis for the assessment tool. The explicit linkage of the milestones with the EPA assessment allows a more definitive "picture" of the learner to emerge at each advancing level of performance of the EPA. This "picture" can be shared with those directly observing the learner and thus provides a potential model for a more reliable assessment of learners performing EPAs and perhaps a more consistent approach to entrustment decisions. The authors hope that Aylward and colleagues' article will be one of many that aim to help the medical education community understand how to implement EPAs as a framework for competency demonstration, as educators try to determine what works, under what conditions and in what settings. Only through a committed effort to share lessons learned can the promise of the theory be translated to practice in the field. PMID:24892405

  8. Active-Passive-Intuitive Learning Theory: A Unified Theory of Learning and Development

    ERIC Educational Resources Information Center

    Sigette, Tyson

    2009-01-01

    This paper addresses many theories of learning and human development which are very similar with regards as to how they suggest learning occurs. The differences in most of the theories exist in how they treat the development of the learner compared to methods of teaching. Most of the major learning theories taught to educators today are based on…

  9. A Case Study Analysis of a Constructionist Knowledge Building Community with Activity Theory

    ERIC Educational Resources Information Center

    Ang, Chee S.; Zaphiris, Panayiotis; Wilson, Stephanie

    2011-01-01

    This article investigates how activity theory can help research a constructionist community. We present a constructionist activity model called CONstructionism Through ACtivity Theory (CONTACT) model and explain how it can be used to analyse the constructionist activity in knowledge building communities. We then illustrate the model through its…

  10. Comparing droplet activation parameterisations against adiabatic parcel models using a novel inverse modelling framework

    NASA Astrophysics Data System (ADS)

    Partridge, Daniel; Morales, Ricardo; Stier, Philip

    2015-04-01

    Many previous studies have compared droplet activation parameterisations against adiabatic parcel models (e.g. Ghan et al., 2001). However, these have often involved comparisons for a limited number of parameter combinations based upon certain aerosol regimes. Recent studies (Morales et al., 2014) have used wider ranges when evaluating their parameterisations, however, no study has explored the full possible multi-dimensional parameter space that would be experienced by droplet activations within a global climate model (GCM). It is important to be able to efficiently highlight regions of the entire multi-dimensional parameter space in which we can expect the largest discrepancy between parameterisation and cloud parcel models in order to ascertain which regions simulated by a GCM can be expected to be a less accurate representation of the process of cloud droplet activation. This study provides a new, efficient, inverse modelling framework for comparing droplet activation parameterisations to more complex cloud parcel models. To achieve this we couple a Markov Chain Monte Carlo algorithm (Partridge et al., 2012) to two independent adiabatic cloud parcel models and four droplet activation parameterisations. This framework is computationally faster than employing a brute force Monte Carlo simulation, and allows us to transparently highlight which parameterisation provides the closest representation across all aerosol physiochemical and meteorological environments. The parameterisations are demonstrated to perform well for a large proportion of possible parameter combinations, however, for certain key parameters; most notably the vertical velocity and accumulation mode aerosol concentration, large discrepancies are highlighted. These discrepancies correspond for parameter combinations that result in very high/low simulated values of maximum supersaturation. By identifying parameter interactions or regimes within the multi-dimensional parameter space we hope to guide

  11. Microfluidic rheology of active particle suspensions: Kinetic theory.

    PubMed

    Alonso-Matilla, Roberto; Ezhilan, Barath; Saintillan, David

    2016-07-01

    We analyze the effective rheology of a dilute suspension of self-propelled slender particles confined between two infinite parallel plates and subject to a pressure-driven flow. We use a continuum kinetic model to describe the configuration of the particles in the system, in which the disturbance flows induced by the swimmers are taken into account, and use it to calculate estimates of the suspension viscosity for a range of channel widths and flow strengths typical of microfluidic experiments. Our results are in agreement with previous bulk models, and in particular, demonstrate that the effect of activity is strongest at low flow rates, where pushers tend to decrease the suspension viscosity whereas pullers enhance it. In stronger flows, dissipative stresses overcome the effects of activity leading to increased viscosities followed by shear-thinning. The effects of confinement and number density are also analyzed, and our results confirm the apparent transition to superfluidity reported in recent experiments on pusher suspensions at intermediate densities. We also derive an approximate analytical expression for the effective viscosity in the limit of weak flows and wide channels, and demonstrate good agreement between theory and numerical calculations. PMID:27375827

  12. Dynamical theory of active cellular response to external stress.

    PubMed

    De, Rumi; Safran, Samuel A

    2008-09-01

    We present a comprehensive, theoretical treatment of the orientational response to external stress of active, contractile cells embedded in a gel-like elastic medium. The theory includes both the forces that arise from the deformation of the matrix as well as forces due to the internal regulation of the stress fibers and focal adhesions of the cell. We calculate the time-dependent response of both the magnitude and the direction of the elastic dipole that characterizes the active forces exerted by the cell, for various situations. For static or quasistatic external stress, cells orient parallel to the stress while for high frequency dynamic external stress, cells orient nearly perpendicular. Both numerical and analytical calculations of these effects are presented. In addition we predict the relaxation time for the cellular response for both slowly and rapidly varying external stresses; several characteristic scaling regimes for the relaxation time as a function of applied frequency are predicted. We also treat the case of cells for which the regulation of the stress fibers and focal adhesions is controlled by strain (instead of stress) and show that the predicted dependence of the cellular orientation on the Poisson ratio of the matrix can differentiate strain vs stress regulation of cellular response. PMID:18851081

  13. Dynamical theory of active cellular response to external stress

    NASA Astrophysics Data System (ADS)

    de, Rumi; Safran, Samuel A.

    2008-09-01

    We present a comprehensive, theoretical treatment of the orientational response to external stress of active, contractile cells embedded in a gel-like elastic medium. The theory includes both the forces that arise from the deformation of the matrix as well as forces due to the internal regulation of the stress fibers and focal adhesions of the cell. We calculate the time-dependent response of both the magnitude and the direction of the elastic dipole that characterizes the active forces exerted by the cell, for various situations. For static or quasistatic external stress, cells orient parallel to the stress while for high frequency dynamic external stress, cells orient nearly perpendicular. Both numerical and analytical calculations of these effects are presented. In addition we predict the relaxation time for the cellular response for both slowly and rapidly varying external stresses; several characteristic scaling regimes for the relaxation time as a function of applied frequency are predicted. We also treat the case of cells for which the regulation of the stress fibers and focal adhesions is controlled by strain (instead of stress) and show that the predicted dependence of the cellular orientation on the Poisson ratio of the matrix can differentiate strain vs stress regulation of cellular response.

  14. The Work Activity and Participation Outcomes Framework: a new look at work disability outcomes through the lens of the ICF.

    PubMed

    AlHeresh, Rawan A; Keysor, Julie J

    2015-06-01

    Work disability is common among people with chronic conditions. The terminology in the field is variable and often used interchangeably and there is a lack of comprehensive frameworks to describe work as an outcome. Varied operationalization of work disability makes it difficult to establish precise estimates of the impact of chronic musculoskeletal conditions on work. A new conceptual framework was developed using the International Classification of Functioning, Disability and Health and was named 'Work Activity and Participation Outcome (Work APO) Framework' which clarified definitions in the field. Applying the framework to people at risk of work disability and evaluating their outcomes could advance the literature. PMID:25715231

  15. Tailored motivational message generation: A model and practical framework for real-time physical activity coaching.

    PubMed

    Op den Akker, Harm; Cabrita, Miriam; Op den Akker, Rieks; Jones, Valerie M; Hermens, Hermie J

    2015-06-01

    This paper presents a comprehensive and practical framework for automatic generation of real-time tailored messages in behavior change applications. Basic aspects of motivational messages are time, intention, content and presentation. Tailoring of messages to the individual user may involve all aspects of communication. A linear modular system is presented for generating such messages. It is explained how properties of user and context are taken into account in each of the modules of the system and how they affect the linguistic presentation of the generated messages. The model of motivational messages presented is based on an analysis of existing literature as well as the analysis of a corpus of motivational messages used in previous studies. The model extends existing 'ontology-based' approaches to message generation for real-time coaching systems found in the literature. Practical examples are given on how simple tailoring rules can be implemented throughout the various stages of the framework. Such examples can guide further research by clarifying what it means to use e.g. user targeting to tailor a message. As primary example we look at the issue of promoting daily physical activity. Future work is pointed out in applying the present model and framework, defining efficient ways of evaluating individual tailoring components, and improving effectiveness through the creation of accurate and complete user- and context models. PMID:25843359

  16. A framework for activity detection in wide-area motion imagery

    NASA Astrophysics Data System (ADS)

    Porter, Reid; Ruggiero, Christy; Morrison, John D.

    2009-05-01

    As wide-area persistent imaging systems become cost effective, increasingly large areas of the earth can be imaged at relatively high frame rates. Efficient exploitation of the large geo-spatial-temporal datasets produced by these systems poses significant technical challenges for image and video analysis and for data mining. Significant progress in image stabilization, moving object detection and tracking, are allowing automated systems to generate hundreds to thousands of vehicle tracks from raw data, with little human intervention. However, tracking performance at this scale is unreliable, and average track length is much smaller than the average vehicle route. These are limiting factors for applications that depend heavily on track identity, i.e. tracking vehicles from their points of origin to their final destination. In this paper, we propose and evaluate a framework for wide-area motion imagery (WAMI) exploitation that minimizes the dependence on track identity. In its current form, this framework takes noisy, incomplete moving object detection tracks as input, and produces a small set of activities (e.g. multi-vehicle meetings) as output. The framework can be used to focus and direct human users and additional computation, and suggests a path towards high-level content extraction by learning from the human-in-the-loop.

  17. Multi-Standard Metadata Retrieval Framework at the Physical Oceanography Distributed Active Archive Center

    NASA Astrophysics Data System (ADS)

    Chung, N. T.; Huang, T.; Armstrong, E. M.; Gangl, M. E.

    2012-12-01

    With the vast amount of Earth Science data available, providing the user community with high quality metadata to facilitate information retrieval and exchange is integral to scientific research. The Physical Oceanography Distributed Active Archive Center (PO.DAAC) archives and distributes data products along with metadata pertinent to the physical state of the ocean. As one of the Earth Science data center for NASA, PO.DAAC is expected to work with multiple metadata standards. Since there is no single metadata standard that meets everyone's needs, a web-based framework has been designed and integrated as part of PO.DAAC's scalable Core Data System to enable users to quickly retrieve metadata in the format that they need. Currently, the framework supports the Open Search specification for data discovery, ISO 19115-2, Global Change Master Directory (GCMD) and Federal Geographic Data Committee (FGDC) metadata standards, with new metadata standards still being added. In this talk we will present the architecture behind the framework that makes it possible to support various metadata standards as well as the challenges we encountered.

  18. A framework for activity detection in wide-area motion imagery

    SciTech Connect

    Porter, Reid B; Ruggiero, Christy E; Morrison, Jack D

    2009-01-01

    Wide-area persistent imaging systems are becoming increasingly cost effective and now large areas of the earth can be imaged at relatively high frame rates (1-2 fps). The efficient exploitation of the large geo-spatial-temporal datasets produced by these systems poses significant technical challenges for image and video analysis and data mining. In recent years there has been significant progress made on stabilization, moving object detection and tracking and automated systems now generate hundreds to thousands of vehicle tracks from raw data, with little human intervention. However, the tracking performance at this scale, is unreliable and average track length is much smaller than the average vehicle route. This is a limiting factor for applications which depend heavily on track identity, i.e. tracking vehicles from their points of origin to their final destination. In this paper we propose and investigate a framework for wide-area motion imagery (W AMI) exploitation that minimizes the dependence on track identity. In its current form this framework takes noisy, incomplete moving object detection tracks as input, and produces a small set of activities (e.g. multi-vehicle meetings) as output. The framework can be used to focus and direct human users and additional computation, and suggests a path towards high-level content extraction by learning from the human-in-the-loop.

  19. Conceptual framework for standard economic evaluation of physical activity programs in primary prevention.

    PubMed

    Wolfenstetter, Silke B

    2011-12-01

    Economic evaluations of primary prevention physical activity programs have gained importance because of scarce resources in health-care-systems. A concept for economic evaluation should be based on the efficacy of physical activity, the standard methods of economic evaluation and the aims of public health. Previous publications have examined only parts of these components and have not developed a comprehensive conceptual framework; it is the objective of this article to develop such a framework. The derived method should aid decision makers and staff members of intervention programs in reviewing and conducting an economic evaluation. A literature search of articles was done using six electronic databases. Referenced works for standard methods and more comprehensive approaches for evaluation of preventive programs were studied. The newly developed conceptual framework for economic evaluation includes: (1) the type of physical activity program; (2) features of a selected study population; (3) the outcome dimension comprising exercise efficacy, reach, recruitment, response rate, maintenance, compliance and adverse health effects plus the social impact; and (4) the cost dimension consisting of program development costs, program implementation costs including the implementation, recruitment, program, participants' time costs and savings resulting from the health effects of the intervention. Cost-effectiveness also depends on the methodology, such as the chosen perspective, data collection, valuation methods and discounting. If an intervention is not considered cost-effective, it is necessary to check each dimension to find possible failures in order to learn for future interventions. A more detailed economic evaluation is of utmost importance for improved comparability and transferability. PMID:21773728

  20. A Description of the Social-Ecological Framework Used in the Trial of Activity for Adolescent Girls (TAAG)

    ERIC Educational Resources Information Center

    Elder, John P.; Lytle, Leslie; Sallis, James F.; Young, Deborah Rohm; Steckler, Allan; Simons-Morton, Denise; Stone, Elaine; Jobe, Jared B.; Stevens, June; Lohman, Tim; Webber, Larry; Pate, Russell; Saksvig, Brit I.; Ribisl, Kurt

    2007-01-01

    Social-ecological (SE) models are becoming more widely used in health behavior research. Applying SE models to the design of interventions is challenging because models must be tailor-made for each behavior and population, other theories need to be integrated into multi-level frameworks, and empirical research to guide model development is…

  1. Using activity-based costing and theory of constraints to guide continuous improvement in managed care.

    PubMed

    Roybal, H; Baxendale, S J; Gupta, M

    1999-01-01

    Activity-based costing and the theory of constraints have been applied successfully in many manufacturing organizations. Recently, those concepts have been applied in service organizations. This article describes the application of activity-based costing and the theory of constraints in a managed care mental health and substance abuse organization. One of the unique aspects of this particular application was the integration of activity-based costing and the theory of constraints to guide process improvement efforts. This article describes the activity-based costing model and the application of the theory of constraint's focusing steps with an emphasis on unused capacities of activities in the organization. PMID:10350791

  2. Small Molecule Activation by Constrained Phosphorus Compounds: Insights from Theory.

    PubMed

    Pal, Amrita; Vanka, Kumar

    2016-01-19

    An exciting new development in main group chemistry has been the use of a constrained, "flat", phosphorus-based complex to mediate in reactions such as the dehydrogenation of ammonia borane (AB), and the activation of the N-H bond in primary amines. Its importance is based on the fact that it shows that main group compounds, when properly designed, can be as effective as transition metal complexes for doing significant chemical transformations. What the current computational study, employing density functional theory (DFT), reveals is that a common, general mechanism exists that accounts for the behavior of the flat phosphorus compound in the different reactions that have been experimentally reported to date. This mechanism, which involves the mediation by a base as a proton transfer agent, is simpler and energetically more favorable than the previous mechanisms that have been proposed for the same reactions in the literature. It is likely that the knowledge gained from the current work about the chemical behavior of this phosphorus compound can be utilized to design new constrained phosphorus-based compounds. PMID:26700074

  3. New heterometallic zirconium metalloporphyrin frameworks and their heteroatom-activated high-surface-area carbon derivatives.

    PubMed

    Lin, Qipu; Bu, Xianhui; Kong, Aiguo; Mao, Chengyu; Zhao, Xiang; Bu, Fei; Feng, Pingyun

    2015-02-18

    Four cubic zirconium-porphyrin frameworks, CPM-99(H2, Zn, Co, Fe), were synthesized by a molecular-configuration-guided strategy. Augmentation of meso-substituted side arms (with double-torsional biphenyl rings) of tetratopic porphyrin linkers leads to a successful implementation of zirconium-carboxylate frameworks with cubic 2.5 nm cage. The hard-templating effect of Zr6-polyoxo-cluster and uniformly embedded (metallo)porphyrin centers endow CPM-99 with highly desirable properties as precursors for oxygen reduction reaction (ORR) catalysts. The pyrolytic products not only retain the microcubic morphology of the parent CPM-99 but also possess porphyrinic active sites, hierarchical porosity, and highly conducting networks. CPM-99Fe-derived material, denoted CPM-99Fe/C, exhibits the best ORR activity, comparable to benchmark 20% Pt/C in alkaline and acidic media, but CPM-99Fe/C is more durable and methanol-tolerant. This work demonstrates a new route for the development of nonprecious metal ORR catalysts from stable metalloporphyrinic MOFs. PMID:25651395

  4. Solar Activity Predictions Based on Solar Dynamo Theories

    NASA Astrophysics Data System (ADS)

    Schatten, Kenneth H.

    2009-05-01

    We review solar activity prediction methods, statistical, precursor, and recently the Dikpati and the Choudhury groups’ use of numerical flux-dynamo methods. Outlining various methods, we compare precursor techniques with weather forecasting. Precursors involve events prior to a solar cycle. First started by the Russian geomagnetician Ohl, and then Brown and Williams; the Earth's field variations near solar minimum was used to predict the next solar cycle, with a correlation of 0.95. From the standpoint of causality, as well as energetically, these relationships were somewhat bizarre. One index used was the "number of anomalous quiet days,” an antiquated, subjective index. Scientific progress cannot be made without some suspension of disbelief; otherwise old paradigms become tautologies. So, with youthful naïveté, Svalgaard, Scherrer, Wilcox and I viewed the results through rose-colored glasses and pressed ahead searching for understanding. We eventually fumbled our way to explaining how the Sun could broadcast the state of its internal dynamo to Earth. We noted one key aspect of the Babcock-Leighton Flux Dynamo theory: the polar field at the end of a cycle serves as a seed for the next cycle's growth. Near solar minimum this field usually bathes the Earth, and thereby affects geomagnetic indices then. We found support by examining 8 previous solar cycles. Using our solar precursor technique we successfully predicted cycles 21, 22 and 23 using WSO and MWSO data. Pesnell and I improved the method using a SODA (SOlar Dynamo Amplitude) Index. In 2005, nearing cycle 23's minimum, Svalgaard and I noted an unusually weak polar field, and forecasted a small cycle 24. We discuss future advances: the flux-dynamo methods. As far as future solar activity, I shall let the Sun decide; it will do so anyhow.

  5. Metal organic framework-mediated synthesis of highly active and stable Fischer-Tropsch catalysts.

    PubMed

    Santos, Vera P; Wezendonk, Tim A; Jaén, Juan José Delgado; Dugulan, A Iulian; Nasalevich, Maxim A; Islam, Husn-Ubayda; Chojecki, Adam; Sartipi, Sina; Sun, Xiaohui; Hakeem, Abrar A; Koeken, Ard C J; Ruitenbeek, Matthijs; Davidian, Thomas; Meima, Garry R; Sankar, Gopinathan; Kapteijn, Freek; Makkee, Michiel; Gascon, Jorge

    2015-01-01

    Depletion of crude oil resources and environmental concerns have driven a worldwide research on alternative processes for the production of commodity chemicals. Fischer-Tropsch synthesis is a process for flexible production of key chemicals from synthesis gas originating from non-petroleum-based sources. Although the use of iron-based catalysts would be preferred over the widely used cobalt, manufacturing methods that prevent their fast deactivation because of sintering, carbon deposition and phase changes have proven challenging. Here we present a strategy to produce highly dispersed iron carbides embedded in a matrix of porous carbon. Very high iron loadings (>40 wt %) are achieved while maintaining an optimal dispersion of the active iron carbide phase when a metal organic framework is used as catalyst precursor. The unique iron spatial confinement and the absence of large iron particles in the obtained solids minimize catalyst deactivation, resulting in high active and stable operation. PMID:25740709

  6. Metal organic framework-mediated synthesis of highly active and stable Fischer-Tropsch catalysts

    NASA Astrophysics Data System (ADS)

    Santos, Vera P.; Wezendonk, Tim A.; Jaén, Juan José Delgado; Dugulan, A. Iulian; Nasalevich, Maxim A.; Islam, Husn-Ubayda; Chojecki, Adam; Sartipi, Sina; Sun, Xiaohui; Hakeem, Abrar A.; Koeken, Ard C. J.; Ruitenbeek, Matthijs; Davidian, Thomas; Meima, Garry R.; Sankar, Gopinathan; Kapteijn, Freek; Makkee, Michiel; Gascon, Jorge

    2015-03-01

    Depletion of crude oil resources and environmental concerns have driven a worldwide research on alternative processes for the production of commodity chemicals. Fischer-Tropsch synthesis is a process for flexible production of key chemicals from synthesis gas originating from non-petroleum-based sources. Although the use of iron-based catalysts would be preferred over the widely used cobalt, manufacturing methods that prevent their fast deactivation because of sintering, carbon deposition and phase changes have proven challenging. Here we present a strategy to produce highly dispersed iron carbides embedded in a matrix of porous carbon. Very high iron loadings (>40 wt %) are achieved while maintaining an optimal dispersion of the active iron carbide phase when a metal organic framework is used as catalyst precursor. The unique iron spatial confinement and the absence of large iron particles in the obtained solids minimize catalyst deactivation, resulting in high active and stable operation.

  7. Modulation of palladium activity and stability by a covalent triazine framework

    DOE PAGESBeta

    Chan-Thaw, Carine E.; Villa, Alberto; Wang, Di; Biroli, Alessio; Veith, Gabriel M; Thomas, Arne; Prati, Laura

    2015-01-01

    The confinement of a Pd nanoparticle within a nitrogen-containing covalent triazine framework (CTF) material was investigated to understand if the highly tunable CTF chemistry mediates the Pd catalytic properties through an ensemble effect with the CTF nitrogen atoms or a confinement effect within the CTF pores. The results surprisingly demonstrate that the CTF stabilizes the formation of 2.6 nm PdHx particles within the pores. These PdHx particles are very active for the liquid phase oxidation of glycerol due to the in situ formation of H2O2 which catalytically promotes the initial C-C cleavage. In addition the confined particles are stable overmore » many catalytic cycles whereas nanoparticles trapped outside of the pores loose activity rapidly. These results indicate that there is the potential to tune the CTF chemistry to significantly modify the chemistry of the catalytic metals.« less

  8. Understanding Synchronous Computer-Mediated Classroom Discussion through Cultural-Historical Activity Theory

    ERIC Educational Resources Information Center

    Park, Yangjoo

    2015-01-01

    This study is about graduate students' discourse practices in classroom text-based synchronous computer mediated discussions (SCMD). Cultural historical activity theory (in short, Activity Theory) is the primary theoretical lens through which the data are analyzed. Engeström's (1987) Activity System model among the various theoretical positions or…

  9. The Systemic-Structural Theory of Activity: Applications to the Study of Human Work

    ERIC Educational Resources Information Center

    Bedny, Gregory Z.; Harris, Steven Robert

    2005-01-01

    This article offers an introduction to the central concepts and principles of the Systemic-Structural Theory of Activity (SSTA), an activity-theoretical approach specifically tailored to the analysis and design of human work. In activity theory, cognition is understood both as a process and as a structured system of actions. Building on the…

  10. Theoretical frameworks for testing relativistic gravity. IV - A compendium of metric theories of gravity and their post-Newtonian limits.

    NASA Technical Reports Server (NTRS)

    Ni, W.-T.

    1972-01-01

    Metric theories of gravity are compiled and classified according to the types of gravitational fields they contain, and the modes of interaction among those fields. The gravitation theories considered are classified as (1) general relativity, (2) scalar-tensor theories, (3) conformally flat theories, and (4) stratified theories with conformally flat space slices. The post-Newtonian limit of each theory is constructed and its Parametrized Post-Newtonian (PPN) values are obtained by comparing it with Will's version of the formalism. Results obtained here, when combined with experimental data and with recent work by Nordtvedt and Will and by Ni, show that, of all theories thus far examined by our group, the only currently viable ones are general relativity, the Bergmann-Wagoner scalar-tensor theory and its special cases (Nordtvedt; Brans-Dicke-Jordan), and a recent, new vector-tensor theory by Nordtvedt, Hellings, and Will.

  11. Introductory Biology Courses: A Framework To Support Active Learning in Large Enrollment Introductory Science Courses

    PubMed Central

    2005-01-01

    Active learning and research-oriented activities have been increasingly used in smaller, specialized science courses. Application of this type of scientific teaching to large enrollment introductory courses has been, however, a major challenge. The general microbiology lecture/laboratory course described has been designed to incorporate published active-learning methods. Three major case studies are used as platforms for active learning. Themes from case studies are integrated into lectures and laboratory experiments, and in class and online discussions and assignments. Students are stimulated to apply facts to problem-solving and to learn research skills such as data analysis, writing, and working in teams. This course is feasible only because of its organizational framework that makes use of teaching teams (made up of faculty, graduate assistants, and undergraduate assistants) and Web-based technology. Technology is a mode of communication, but also a system of course management. The relevance of this model to other biology courses led to assessment and evaluation, including an analysis of student responses to the new course, class performance, a university course evaluation, and retention of course learning. The results are indicative of an increase in student engagement in research-oriented activities and an appreciation of real-world context by students. PMID:15917873

  12. Highly active non-PGM catalysts prepared from metal organic frameworks

    DOE PAGESBeta

    Barkholtz, Heather M.; Chong, Lina; Kaiser, Zachary B.; Xu, Tao; Liu, Di -Jia

    2015-06-11

    Finding inexpensive alternatives to platinum group metals (PGMs) is essential for reducing the cost of proton exchange membrane fuel cells (PEMFCs). Numerous materials have been investigated as potential replacements of Pt, of which the transition metal and nitrogen-doped carbon composites (TM/Nx/C) prepared from iron doped zeolitic imidazolate frameworks (ZIFs) are among the most active ones in catalyzing the oxygen reduction reaction based on recent studies. In this report, we demonstrate that the catalytic activity of ZIF-based TM/Nx/C composites can be substantially improved through optimization of synthesis and post-treatment processing conditions. Ultimately, oxygen reduction reaction (ORR) electrocatalytic activity must be demonstratedmore » in membrane-electrode assemblies (MEAs) of fuel cells. The process of preparing MEAs using ZIF-based non-PGM electrocatalysts involves many additional factors which may influence the overall catalytic activity at the fuel cell level. Evaluation of parameters such as catalyst loading and perfluorosulfonic acid ionomer to catalyst ratio were optimized. Our overall efforts to optimize both the catalyst and MEA construction process have yielded impressive ORR activity when tested in a fuel cell system.« less

  13. Highly active non-PGM catalysts prepared from metal organic frameworks

    SciTech Connect

    Barkholtz, Heather M.; Chong, Lina; Kaiser, Zachary B.; Xu, Tao; Liu, Di -Jia

    2015-06-11

    Finding inexpensive alternatives to platinum group metals (PGMs) is essential for reducing the cost of proton exchange membrane fuel cells (PEMFCs). Numerous materials have been investigated as potential replacements of Pt, of which the transition metal and nitrogen-doped carbon composites (TM/Nx/C) prepared from iron doped zeolitic imidazolate frameworks (ZIFs) are among the most active ones in catalyzing the oxygen reduction reaction based on recent studies. In this report, we demonstrate that the catalytic activity of ZIF-based TM/Nx/C composites can be substantially improved through optimization of synthesis and post-treatment processing conditions. Ultimately, oxygen reduction reaction (ORR) electrocatalytic activity must be demonstrated in membrane-electrode assemblies (MEAs) of fuel cells. The process of preparing MEAs using ZIF-based non-PGM electrocatalysts involves many additional factors which may influence the overall catalytic activity at the fuel cell level. Evaluation of parameters such as catalyst loading and perfluorosulfonic acid ionomer to catalyst ratio were optimized. Our overall efforts to optimize both the catalyst and MEA construction process have yielded impressive ORR activity when tested in a fuel cell system.

  14. Active transporters as enzymes: an energetic framework applied to major facilitator superfamily and ABC importer systems.

    PubMed

    Shilton, Brian H

    2015-04-15

    Active membrane transporters are dynamic molecular machines that catalyse transport across a membrane by coupling solute movement to a source of energy such as ATP or a secondary ion gradient. A central question for many active transporters concerns the mechanism by which transport is coupled to a source of energy. The transport process and associated energetic coupling involve conformational changes in the transporter. For efficient transport, the conformational changes must be tightly regulated and they must link energy use to movement of the substrate across the membrane. The present review discusses active transport using the well-established energetic framework for enzyme-mediated catalysis. In particular, membrane transport systems can be viewed as ensembles consisting of low-energy and high-energy conformations. The transport process involves binding interactions that selectively stabilize the higher energy conformations, and in this way promote conformational changes in the system that are coupled to decreases in free energy and substrate translocation. The major facilitator superfamily of secondary active transporters is used to illustrate these ideas, which are then be expanded to primary active transport mediated by ABC (ATP-binding cassette) import systems, with a focus on the well-studied maltose transporter. PMID:25837849

  15. Sociological Understandings of Conduct for a Noncanonical Activity Theory: Exploring Intersections and Complementarities

    ERIC Educational Resources Information Center

    Sawchuk, Peter H.; Stetsenko, Anna

    2008-01-01

    Following a discussion of activity theory as an approach to human development originally rooted in transformational change, we review the historical context and diverse conceptualizations of social conduct from the field of sociology. The discussion of social conduct is broken into theories of social action, theories of enactment, and contemporary…

  16. The Bourgeoisie Dream Factory: Teaching Marx's Theory of Alienation through an Experiential Activity

    ERIC Educational Resources Information Center

    Windsor, Elroi J.; Carroll, Alana M.

    2015-01-01

    Effectively teaching sociological theories to undergraduate students is challenging. Students often enroll in theory courses due to major requirements, not personal interest. Consequently, many students approach the study of theory with anxiety. This study examined the effectiveness of an experiential learning activity designed to teach Karl…

  17. The Theory of "Belonging": Defining Concepts Used within Belonging, Being and Becoming--the Australian Early Years Learning Framework

    ERIC Educational Resources Information Center

    Peers, Chris; Fleer, Marilyn

    2014-01-01

    The implementation in 2009-10 of the Early Years Learning Framework (EYLF) spearheaded the efforts of the Australian Commonwealth government to institute a national curriculum. The theme of the new early childhood framework follows three guiding concepts: Belonging, Being and Becoming. In this article, we discuss these three concepts in order to…

  18. Young Children's Motivational Frameworks and Math Achievement: Relation to Teacher-Reported Instructional Practices, but Not Teacher Theory of Intelligence

    ERIC Educational Resources Information Center

    Park, Daeun; Gunderson, Elizabeth A.; Tsukayama, Eli; Levine, Susan C.; Beilock, Sian L.

    2016-01-01

    Although students' motivational frameworks (entity vs. incremental) have been linked to academic achievement, little is known about how early this link emerges and how motivational frameworks develop in the first place. In a year-long study (student N = 424, Teacher N = 58), we found that, as early as 1st and 2nd grade, children who endorsed an…

  19. Participation in Peer Response as Activity: An Examination of Peer Response Stances from an Activity Theory Perspective

    ERIC Educational Resources Information Center

    Zhu, Wei; Mitchell, Deborah A.

    2012-01-01

    This article reports a case study that examined English as a Second Language students' peer response stances from an activity theory perspective. More specifically, the study was guided by the constructs of activity and motive/object in Leont'ev's theory. Multiple sources of data were collected from two native Spanish-speaking students enrolled in…

  20. T-cell activation: A queuing theory analysis at low agonist density.

    PubMed

    Wedagedera, J R; Burroughs, N J

    2006-09-01

    We analyze a simple linear triggering model of the T-cell receptor (TCR) within the framework of queuing theory, in which TCRs enter the queue upon full activation and exit by downregulation. We fit our model to four experimentally characterized threshold activation criteria and analyze their specificity and sensitivity: the initial calcium spike, cytotoxicity, immunological synapse formation, and cytokine secretion. Specificity characteristics improve as the time window for detection increases, saturating for time periods on the timescale of downregulation; thus, the calcium spike (30 s) has low specificity but a sensitivity to single-peptide MHC ligands, while the cytokine threshold (1 h) can distinguish ligands with a 30% variation in the complex lifetime. However, a robustness analysis shows that these properties are degraded when the queue parameters are subject to variation-for example, under stochasticity in the ligand number in the cell-cell interface and population variation in the cellular threshold. A time integration of the queue over a period of hours is shown to be able to control parameter noise efficiently for realistic parameter values when integrated over sufficiently long time periods (hours), the discrimination characteristics being determined by the TCR signal cascade kinetics (a kinetic proofreading scheme). Therefore, through a combination of thresholds and signal integration, a T cell can be responsive to low ligand density and specific to agonist quality. We suggest that multiple threshold mechanisms are employed to establish the conditions for efficient signal integration, i.e., coordinate the formation of a stable contact interface. PMID:16766611

  1. Eliciting Metacognitive Experiences and Reflection in a Year 11 Chemistry Classroom: An Activity Theory Perspective

    NASA Astrophysics Data System (ADS)

    Thomas, Gregory P.; McRobbie, Campbell J.

    2013-06-01

    Concerns regarding students' learning and reasoning in chemistry classrooms are well documented. Students' reasoning in chemistry should be characterized by conscious consideration of chemical phenomenon from laboratory work at macroscopic, molecular/sub-micro and symbolic levels. Further, students should develop metacognition in relation to such ways of reasoning about chemistry phenomena. Classroom change eliciting metacognitive experiences and metacognitive reflection is necessary to shift entrenched views of teaching and learning in students. In this study, Activity Theory is used as the framework for interpreting changes to the rules/customs and tools of the activity systems of two different classes of students taught by the same teacher, Frances, who was teaching chemical equilibrium to those classes in consecutive years. An interpretive methodology involving multiple data sources was employed. Frances explicitly changed her pedagogy in the second year to direct students attention to increasingly consider chemical phenomena at the molecular/sub-micro level. Additionally, she asked students not to use the textbook until toward the end of the equilibrium unit and sought to engage them in using their prior knowledge of chemistry to understand their observations from experiments. Frances' changed pedagogy elicited metacognitive experiences and reflection in students and challenged them to reconsider their metacognitive beliefs about learning chemistry and how it might be achieved. While teacher change is essential for science education reform, students are not passive players in change efforts and they need to be convinced of the viability of teacher pedagogical change in the context of their goals, intentions, and beliefs.

  2. Understanding physical activity in individuals with prediabetes: an application of social cognitive theory.

    PubMed

    Taylor, Lorian M; Raine, Kim D; Plotnikoff, Ronald C; Vallance, Jeff K; Sharma, Arya M; Spence, John C

    2016-01-01

    Despite well-documented evidence implicating physical activity (PA) in the prevention of type 2 diabetes, the overwhelming majority of individuals with prediabetes are not physically active enough. The purpose of this study was to investigate the applicability of the social cognitive theory (SCT) in understanding PA behaviour in individuals with prediabetes. Individuals with prediabetes (N = 232) completed a mailed questionnaire assessing demographics, self-reported PA (MET.min/wk) and SCT constructs for PA MET.min/wk. For PA MET.min/wk, scheduling and task efficacy both had significant effects on PA (β = .30 and .22, respectively). Goal formation also had a direct effect on PA for scheduling, coping and task efficacy (β = .20, .34 and .30, respectively). Task, coping and scheduling efficacy explained a significant portion of the variance in PA behaviour. Overall, SCT appears to have merit as a model for understanding PA in individuals with prediabetes. Further evaluative inquiry is needed to establish support for the use of the SCT as a framework for developing, implementing and evaluating PA behaviour change interventions in this population. PMID:26300537

  3. Microscopic theory of the glassy dynamics of passive and active network materials

    NASA Astrophysics Data System (ADS)

    Wang, Shenshen; Wolynes, Peter G.

    2013-03-01

    Signatures of glassy dynamics have been identified experimentally for a rich variety of materials in which molecular networks provide rigidity. Here we present a theoretical framework to study the glassy behavior of both passive and active network materials. We construct a general microscopic network model that incorporates nonlinear elasticity of individual filaments and steric constraints due to crowding. Based on constructive analogies between structural glass forming liquids and random field Ising magnets implemented using a heterogeneous self-consistent phonon method, our scheme provides a microscopic approach to determine the mismatch surface tension and the configurational entropy, which compete in determining the barrier for structural rearrangements within the random first order transition theory of escape from a local energy minimum. The influence of crosslinking on the fragility of inorganic network glass formers is recapitulated by the model. For active network materials, the mapping, which correlates the glassy characteristics to the network architecture and properties of nonequilibrium motor processes, is shown to capture several key experimental observations on the cytoskeleton of living cells: Highly connected tense networks behave as strong glass formers; intense motor action promotes reconfiguration. The fact that our model assuming a negative motor susceptibility predicts the latter suggests that on average the motorized processes in living cells do resist the imposed mechanical load. Our calculations also identify a spinodal point where simultaneously the mismatch penalty vanishes and the mechanical stability of amorphous packing disappears.

  4. Designing for Culturally Contextualized Learning Activity Planning: Matching Learning Theories and Practice

    NASA Astrophysics Data System (ADS)

    de Carvalho, Aparecido Fabiano Pinatti; Anacleto, Junia Coutinho; de Almeida Neris, Vania Paula

    Helping teachers in their activities has been an issue more and more explored in Computer Science. However, in order to support teachers effectively, it is necessary to understand their needs and to design tools that they can easily manage. One of those needs is undoubtedly to put in practice pedagogical principles. This paper presents the design of PACO-T, a tool for helping teachers in planning learning activities (LAs) supported by common sense knowledge, based on PACO, a seven-step textual framework for planning pedagogically suitable LAs. The design was based on the results of a case study carried out to investigate how teachers can plan LAs following PACO steps, using common sense knowledge from a common sense knowledge base collaboratively built through the web. Moreover, the interface design was ruled by a Web Design Pattern Language, attempting to improve the usability of the tool. PACO-T aims to help teachers to put in practice the recommendation for contextualizing LAs to the target group, found in several learning theories.

  5. Microscopic theory of the glassy dynamics of passive and active network materials.

    PubMed

    Wang, Shenshen; Wolynes, Peter G

    2013-03-28

    Signatures of glassy dynamics have been identified experimentally for a rich variety of materials in which molecular networks provide rigidity. Here we present a theoretical framework to study the glassy behavior of both passive and active network materials. We construct a general microscopic network model that incorporates nonlinear elasticity of individual filaments and steric constraints due to crowding. Based on constructive analogies between structural glass forming liquids and random field Ising magnets implemented using a heterogeneous self-consistent phonon method, our scheme provides a microscopic approach to determine the mismatch surface tension and the configurational entropy, which compete in determining the barrier for structural rearrangements within the random first order transition theory of escape from a local energy minimum. The influence of crosslinking on the fragility of inorganic network glass formers is recapitulated by the model. For active network materials, the mapping, which correlates the glassy characteristics to the network architecture and properties of nonequilibrium motor processes, is shown to capture several key experimental observations on the cytoskeleton of living cells: Highly connected tense networks behave as strong glass formers; intense motor action promotes reconfiguration. The fact that our model assuming a negative motor susceptibility predicts the latter suggests that on average the motorized processes in living cells do resist the imposed mechanical load. Our calculations also identify a spinodal point where simultaneously the mismatch penalty vanishes and the mechanical stability of amorphous packing disappears. PMID:23556772

  6. T-Cell Activation: A Queuing Theory Analysis at Low Agonist Density

    PubMed Central

    Wedagedera, J. R.; Burroughs, N. J.

    2006-01-01

    We analyze a simple linear triggering model of the T-cell receptor (TCR) within the framework of queuing theory, in which TCRs enter the queue upon full activation and exit by downregulation. We fit our model to four experimentally characterized threshold activation criteria and analyze their specificity and sensitivity: the initial calcium spike, cytotoxicity, immunological synapse formation, and cytokine secretion. Specificity characteristics improve as the time window for detection increases, saturating for time periods on the timescale of downregulation; thus, the calcium spike (30 s) has low specificity but a sensitivity to single-peptide MHC ligands, while the cytokine threshold (1 h) can distinguish ligands with a 30% variation in the complex lifetime. However, a robustness analysis shows that these properties are degraded when the queue parameters are subject to variation—for example, under stochasticity in the ligand number in the cell-cell interface and population variation in the cellular threshold. A time integration of the queue over a period of hours is shown to be able to control parameter noise efficiently for realistic parameter values when integrated over sufficiently long time periods (hours), the discrimination characteristics being determined by the TCR signal cascade kinetics (a kinetic proofreading scheme). Therefore, through a combination of thresholds and signal integration, a T cell can be responsive to low ligand density and specific to agonist quality. We suggest that multiple threshold mechanisms are employed to establish the conditions for efficient signal integration, i.e., coordinate the formation of a stable contact interface. PMID:16766611

  7. The Human Side of Science Education: Using McGregor's Theory Y as a Framework for Improving Student Motivation

    ERIC Educational Resources Information Center

    Markwell, John

    2004-01-01

    Student motivation is correlated with learning. Douglas McGregor's Theory X and Theory Y as a basis for understanding and improving motivation in the business world can be directly applied to the science classroom. Teachers with a Theory Y perspective (students naturally want to learn) provide increased motivation for students and promote more…

  8. The application of language-game theory to the analysis of science learning: Developing an interpretive classroom-level learning framework

    NASA Astrophysics Data System (ADS)

    Ahmadibasir, Mohammad

    In this study an interpretive learning framework that aims to measure learning on the classroom level is introduced. In order to develop and evaluate the value of the framework, a theoretical/empirical study is designed. The researcher attempted to illustrate how the proposed framework provides insights on the problem of classroom-level learning. The framework is developed by construction of connections between the current literature on science learning and Wittgenstein's language-game theory. In this framework learning is defined as change of classroom language-game or discourse. In the proposed framework, learning is measured by analysis of classroom discourse. The empirical explanation power of the framework is evaluated by applying the framework in the analysis of learning in a fifth-grade science classroom. The researcher attempted to analyze how students' colloquial discourse changed to a discourse that bears more resemblance to science discourse. The results of the empirical part of the investigation are presented in three parts: first, the gap between what students did and what they were supposed to do was reported. The gap showed that students during the classroom inquiry wanted to do simple comparisons by direct observation, while they were supposed to do tool-assisted observation and procedural manipulation for a complete comparison. Second, it was illustrated that the first attempt to connect the colloquial to science discourse was done by what was immediately intelligible for students and then the teacher negotiated with students in order to help them to connect the old to the new language-game more purposefully. The researcher suggested that these two events in the science classroom are critical in discourse change. Third, it was illustrated that through the academic year, the way that students did the act of comparison was improved and by the end of the year more accurate causal inferences were observable in classroom communication. At the end of the

  9. Evaluating the capacity of theories of justice to serve as a justice framework for international clinical research.

    PubMed

    Pratt, Bridget; Zion, Deborah; Loff, Bebe

    2012-01-01

    This article investigates whether or not theories of justice from political philosophy, first, support the position that health research should contribute to justice in global health, and second, provide guidance about what is owed by international clinical research (ICR) actors to parties in low- and middle-income countries. Four theories-John Rawls's theory of justice, the rights-based cosmopolitan theories of Thomas Pogge and Henry Shue, and Jennifer Ruger's health capability paradigm-are evaluated. The article shows that three of the four theories require the conduct of health research for justice in global health. The theories help identify the ends of justice to which ICR is to contribute, but they cannot tell us how to organize ICR to promote these ends. Aside from Ruger's health capability paradigm, the theories also lack an allocative principle for assigning specific duties to specific actors. This creates difficulties for establishing obligations for certain types of ICR actors. PMID:23072678

  10. Active and Durable Hydrogen Evolution Reaction Catalyst Derived from Pd-Doped Metal-Organic Frameworks.

    PubMed

    Chen, Jitang; Xia, Guoliang; Jiang, Peng; Yang, Yang; Li, Ren; Shi, Ruohong; Su, Jianwei; Chen, Qianwang

    2016-06-01

    The water electrolysis is of critical importance for sustainable hydrogen production. In this work, a highly efficient and stable PdCo alloy catalyst (PdCo@CN) was synthesized by direct annealing of Pd-doped metal-organic frameworks (MOFs) under N2 atmosphere. In 0.5 M H2SO4 solution, PdCo@CN displays remarkable electrocatalytic performance with overpotential of 80 mV, a Tafel slope of 31 mV dec(-1), and excellent stability of 10 000 cycles. Our studies reveal that noble metal doped MOFs are ideal precursors for preparing highly active alloy electrocatalysts with low content of noble metal. PMID:27112733

  11. The TATL Framework for CALL Development

    ERIC Educational Resources Information Center

    Ni Chiaráin, Neasa; Ni Chasaide, Ailbhe

    2015-01-01

    The Theory Actions Technology Learner context (TATL) framework provides an initial analysis tool to guide Computer-Assisted Language Learning (CALL) development. It entails joint consideration of four key factors that need to be considered prior and during development activities: (1) the underlying pedagogical theory; (2) the learning tasks…

  12. Electrochemistry and electrochemiluminescence from a redox-active metal-organic framework.

    PubMed

    Xu, Yang; Yin, Xue-Bo; He, Xi-Wen; Zhang, Yu-Kui

    2015-06-15

    The marriage of metal-organic frameworks (MOFs) and electrochemiluminescence (ECL) can combine their merits together. Designing ECL-active MOF with a high electron transfer capacity and high stability is critical for ECL emission. Here we reported the ECL from a redox-active MOF prepared from {Ru[4,4'-(HO2C)2-bpy]2bpy}(2+) and Zn(2+); a property of MOFs has not been reported previously. The MOF structure is independent of its charge and is therefore stable electrochemically. The redox-activity and well-ordered porous structure of the MOF were confirmed by its electrochemical properties and ECL emission. The high ECL emission indicated the ease of electron transfer between the MOF and co-reactants. Furthermore, the MOF exhibited permselectivity, charge selectivity, and catalytic selectivity along with a stable and concentration-dependent ECL emission toward co-reactants. ECL mechanism was proposed based on the results. The detection and recovery of cocaine in the serum sample was used to validate the feasibility of MOF- based ECL system. The information obtained in this study provides a better understanding of the redox properties of MOFs and their potential electrochemical applications. PMID:25569877

  13. Expanding the Foci of Activity Theory: Accessing the Broader Contexts and Experiences of Mathematics Education Reform

    ERIC Educational Resources Information Center

    Venkat, Hamsa; Adler, Jill

    2008-01-01

    In this paper, we consider our use of activity theory to examine empirical data from a study of reform in England--the implementation of the mathematics strand of the Key Stage 3 Strategy in two schools. Our concerns are largely methodological--we consider the aspects of reform that more traditional activity theory methods and foci were able to…

  14. Divisions of Labour: Activity Theory, Multi-Professional Working and Intervention Research

    ERIC Educational Resources Information Center

    Warmington, Paul

    2011-01-01

    This article draws upon, but also critiques, activity theory by combining analysis of how an activity theory derived research intervention attempted to address both everyday work practices and organisational power relationships among children's services professionals. It offers two case studies of developmental work research (DWR) interventions in…

  15. Facile xenon capture and release at room temperature using a metal-organic framework: a comparison with activated charcoal

    SciTech Connect

    Thallapally, Praveen K.; Grate, Jay W.; Motkuri, Radha K.

    2012-01-11

    Two well known Metal organic frameworks (MOF-5, NiDOBDC) were synthesized and studied for facile xenon capture and separation. Our results indicate the NiDOBDC adsorbs significantly more xenon than MOF-5, releases it more readily than activated carbon, and is more selective for Xe over Kr than activated carbon.

  16. Activity Theory Framework and Cognitive Perspectives in Designing Technology-Based Support Systems.

    ERIC Educational Resources Information Center

    Sheu, Feng-Ru

    With the increased demand and interest in electronic performance support systems (EPSS), particularly for supporting knowledge-based problems solving expertise in the information age (Gustafson, 2000; Dickelman, 2000; Kasvi & Vartiainen, 2000), instructional designers are facing a new challenge designing a system that could deliver (or transfer)…

  17. Activity Theory: A Framework for Understanding Multi-Agency Working and Engaging Service Users in Change

    ERIC Educational Resources Information Center

    Greenhouse, Paul Michael

    2013-01-01

    This article discusses the quality of professional relationships between educational psychologists (EPs) and other professionals who work around children, young people and their families as part of a multi-agency team (MAT). The perceived barriers to, and facilitators of, effective multi-agency working are explored in relation to their potential…

  18. [I. P. Pavlov's theory on higher nervous activity: the landmarks and trends in its development].

    PubMed

    Chilingarian, L I

    1999-01-01

    The theory of higher nervous activity created in Pavlovian time is compared with the present-day state of the theory developing due to appearance of new methods, techniques, facts, and concepts. Three principles of Pavlovian theory: determinism; analysis and synthesis; structural approach, as well s types of conditioned reflexes and techniques, types of higher nervous activity, and inhibition problems are discussed. The theory of higher nervous activity is schematically depicted as a tree, some branches of which are presented by facts and concepts obtained and introduced by I.P. Pavlov and his followers during his life, the others are formed by new facts and concepts advancing the theory. What is obsolete in the theory, what are the most prominent tendencies of its development and its new branches are discussed. PMID:10693269

  19. INCORPORATING ROUTINE ACTIVITIES, ACTIVITY SPACES, AND SITUATIONAL DEFINITIONS INTO THE SOCIAL SCHEMATIC THEORY OF CRIME*

    PubMed Central

    BARR, ASHLEY B.; LEI, MAN-KIT; STEWART, ERIC

    2014-01-01

    Simons and Burt’s (2011) social schematic theory (SST) of crime posits that adverse social factors are associated with offending because they promote a set of social schemas (i.e., a criminogenic knowledge structure) that elevates the probability of situational definitions favorable to crime. This study extends the SST model by incorporating the role of contexts for action. Furthermore, the study advances tests of the SST by incorporating a measure of criminogenic situational definitions to assess whether such definitions mediate the effects of schemas and contexts on crime. Structural equation models using 10 years of panel data from 582 African American youth provided strong support for the expanded theory. The results suggest that childhood and adolescent social adversity fosters a criminogenic knowledge structure as well as selection into criminogenic activity spaces and risky activities, all of which increase the likelihood of offending largely through situational definitions. Additionally, evidence shows that the criminogenic knowledge structure interacts with settings to amplify the likelihood of situational definitions favorable to crime. PMID:26392633

  20. Pregnant women's perceptions of weight gain, physical activity, and nutrition using Theory of Planned Behavior constructs.

    PubMed

    Whitaker, Kara M; Wilcox, Sara; Liu, Jihong; Blair, Steven N; Pate, Russell R

    2016-02-01

    A better understanding of women's perceptions of weight gain and related behaviors during pregnancy is necessary to inform behavioral interventions. We used the Theory of Planned Behavior (TPB) to examine pregnant women's perceptions and intentions toward weight gain, physical activity (PA), and nutrition using a mixed methods study design. Women between 20 and 30 weeks gestation (n = 189) were recruited to complete an Internet-based survey. Salient beliefs toward weight gain, PA, and nutrition were captured through open-ended responses and content analyzed into themes. TPB constructs (attitude, subjective norm, perceived behavioral control, intentions) were examined using Pearson correlations and hierarchical linear regression models. Salient beliefs were consistent with the existing literature in non-pregnant populations, with the addition of many pregnancy-specific beliefs. TPB constructs accounted for 23-39 % of the variance in weight gain, PA, and nutrition intentions, and made varying contributions across outcomes. The TPB is a useful framework for examining women's weight-related intentions during pregnancy. Study implications for intervention development are discussed. PMID:26335313

  1. A point process framework for relating neural spiking activity to spiking history, neural ensemble, and extrinsic covariate effects.

    PubMed

    Truccolo, Wilson; Eden, Uri T; Fellows, Matthew R; Donoghue, John P; Brown, Emery N

    2005-02-01

    Multiple factors simultaneously affect the spiking activity of individual neurons. Determining the effects and relative importance of these factors is a challenging problem in neurophysiology. We propose a statistical framework based on the point process likelihood function to relate a neuron's spiking probability to three typical covariates: the neuron's own spiking history, concurrent ensemble activity, and extrinsic covariates such as stimuli or behavior. The framework uses parametric models of the conditional intensity function to define a neuron's spiking probability in terms of the covariates. The discrete time likelihood function for point processes is used to carry out model fitting and model analysis. We show that, by modeling the logarithm of the conditional intensity function as a linear combination of functions of the covariates, the discrete time point process likelihood function is readily analyzed in the generalized linear model (GLM) framework. We illustrate our approach for both GLM and non-GLM likelihood functions using simulated data and multivariate single-unit activity data simultaneously recorded from the motor cortex of a monkey performing a visuomotor pursuit-tracking task. The point process framework provides a flexible, computationally efficient approach for maximum likelihood estimation, goodness-of-fit assessment, residual analysis, model selection, and neural decoding. The framework thus allows for the formulation and analysis of point process models of neural spiking activity that readily capture the simultaneous effects of multiple covariates and enables the assessment of their relative importance. PMID:15356183

  2. A conceptual framework for organizational readiness to implement nutrition and physical activity programs in early childhood education settings.

    PubMed

    Sharma, Shreela V; Upadhyaya, Mudita; Schober, Daniel J; Byrd-Williams, Courtney

    2014-01-01

    Across multiple sectors, organizational readiness predicts the success of program implementation. However, the factors influencing readiness of early childhood education (ECE) organizations for implementation of new nutrition and physical activity programs is poorly understood. This study presents a new conceptual framework to measure organizational readiness to implement nutrition and physical activity programs in ECE centers serving children aged 0 to 5 years. The framework was validated for consensus on relevance and generalizability by conducting focus groups; the participants were managers (16 directors and 2 assistant directors) of ECE centers. The framework theorizes that it is necessary to have "collective readiness," which takes into account such factors as resources, organizational operations, work culture, and the collective attitudes, motivation, beliefs, and intentions of ECE staff. Results of the focus groups demonstrated consensus on the relevance of proposed constructs across ECE settings. Including readiness measures during program planning and evaluation could inform implementation of ECE programs targeting nutrition and physical activity behaviors. PMID:25357258

  3. Mediation of Effects of a Theory-Based Behavioral Intervention on Self-Reported Physical Activity in South African Men

    PubMed Central

    Jemmott, John B.; Stephens, Alisa; O’Leary, Ann; Jemmott, Loretta Sweet; Teitelman, Anne; Ngwane, Zolani; Mtose, Xoliswa

    2015-01-01

    Objective Increasing physical activity is an important public-health goal worldwide, but there are few published mediation analyses of physical-activity interventions in low-to-middle-income countries like South Africa undergoing a health transition involving markedly increased mortality from non-communicable diseases. This article reports secondary analyses on the mediation of a theory-of-planned-behavior-based behavioral intervention that increased self-reported physical activity in a trial with 1,181 men in Eastern Cape Province, South Africa. Method Twenty-two matched-pairs of neighborhoods were randomly selected. Within pairs, neighborhoods were randomized to a health-promotion intervention or an attention-matched control intervention with baseline, immediate-post, and 6- and 12-month post-intervention assessments. Theory-of-planned-behavior constructs measured immediately post-intervention were tested as potential mediators of the primary outcome, self-reported physical activity averaged over the 6- and 12-month post-intervention assessments, using a product-of-coefficients approach in a generalized-estimating-equations framework. Data were collected in 2007–2010. Results Attitude, subjective norm, self-efficacy, and intention were significant mediators of intervention-induced increases in self-reported physical activity. The descriptive norm, not affected by the intervention, was not a mediator, but predicted increased self-reported physical activity. Conclusion The results suggest that interventions targeting theory-of-planned-behavior constructs may contribute to efforts to increase physical activity to reduce the burden of non-communicable diseases among South African men. PMID:25565482

  4. Active Learning with Monty Hall in a Game Theory Class

    ERIC Educational Resources Information Center

    Brokaw, Alan J.; Merz, Thomas E.

    2004-01-01

    The authors describe a game that students can play on the first day of a game theory class. The game introduces the 4 essential elements of any game and is designed so that its sequel, also played on the first day of class, has students playing the well-known Monty Hall game, which raises the question: Should you switch doors? By implementing a…

  5. Do Differences in Brain Activation Challenge Universal Theories of Dyslexia?

    ERIC Educational Resources Information Center

    Ziegler, Johannes C.

    2006-01-01

    It has been commonly agreed that developmental dyslexia in different languages has a common biological origin: a dysfunction of left posterior temporal brain regions dealing with phonological processes. Siok, Perfetti, Jin, and Tan (2004, "Nature," 431, 71-76) challenge this biological unity theory of dyslexia: Chinese dyslexics show no deficits…

  6. A New Framework for Robust Retrieval and Fusion of Active/Passive Multi-Sensor Precipitation

    NASA Astrophysics Data System (ADS)

    Ebtehaj, M.; Foufoula-Georgiou, E.; Bras, R. L.

    2014-12-01

    This study introduces a new inversion approach for simultaneous retrieval and optimal fusion of multi-sensor passive/active precipitation spaceborne observations relevant to the Global Precipitation Measurement (GPM) constellation of satellites. This approach uses a modern Maximum a Posteriori (MAP) Bayesian estimator and variational principles to obtain a robust estimate of the rainfall profile from multiple sources of observationally- and physically-based a priori generated databases. The MAP estimator makes use of a constrained mixed and -norm regularization that warranties improved stability and reduced estimation error compared to the classic least-squares estimators, often used in the Bayesian rainfall retrieval techniques. We demonstrate the promise of our framework via detailed algorithmic implementation using the passive and active multi-sensor observations provided by the microwave imager (TMI) and precipitation radar (PR) aboard the Tropical Rainfall Measuring Mission (TRMM) satellite. To this end, we simultaneously obtain an observationally-driven retrieval of the entire precipitation profile using the coincidental TMI-PR observations and then optimally combine it with a first guess derived from physically-consistent a priori collected database of the TMI-2A12 operational product. We elucidate the performance of our algorithm for a wide range of storm environments with a specific focus on extreme and light precipitation events over land and coastal areas for hydrologic applications. The results are also validated versus the ground based observations and the standard TRMM products in seasonal and annual timescales.

  7. Predictors of physical activity among rural and small town breast cancer survivors: an application of the theory of planned behaviour.

    PubMed

    Vallance, Jeff K; Lavallee, Celeste; Culos-Reed, Nicole S; Trudeau, Marc G

    2012-01-01

    The primary objective of this study was to investigate the utility of the two-component theory of planned behaviour (TPB) in understanding physical activity intentions and behaviour in rural and small town breast cancer survivors. The secondary objective was to elicit the most common behavioural, normative and control beliefs of rural and small town survivors regarding physical activity. Using a cross-sectional survey design, 524 rural and small town breast cancer survivors completed a mailed survey that assessed physical activity and TPB variables. Physical activity intention explained 12% of the variance in physical activity behaviour (p < 0.01) while the TPB constructs together explained 43% of the variance in physical activity intention (p < 0.01). Unique behavioural, normative and control beliefs were elicited from the sample. The two-component TPB framework appears to be a suitable model to initiate an understanding of physical activity determinants among rural and small town breast cancer survivors. These data can be used in the development and establishment of physical activity behaviour interventions and health promotion materials designed to facilitate physical activity behaviour among rural and small town breast cancer survivors. PMID:22409699

  8. Self-Reported Pediatric Measures of Physical Activity, Sedentary Behavior and Strength Impact for PROMIS®: Conceptual Framework

    PubMed Central

    Tucker, Carole A.; Bevans, Katherine B.; Teneralli, Rachel E.; Smith, Ashley Wilder; Bowles, Heather R; Forrest, Christopher B.

    2014-01-01

    Purpose Children's physical activity (PA) levels are commonly assessed in pediatric clinical research, but rigorous self-report assessment tools for children are scarce, and computer adaptive test implementations are rare. Our objective was to improve pediatric self-report measures of activity using semi-structured interviews with experts and children for conceptualization of a child-informed framework. Methods Semi-structured interviews were conducted to conceptualize physical activity, sedentary behaviors, and strengthening activities. We performed systematic literature reviews to identify item-level concepts used to assess these 3 domains. Results We developed conceptual frameworks for each domain using words and phrases identified by children as relevant. Conclusions Semi-structured interview methods provide valuable information of children's perspectives and the ways children recall previous activities. Conceptualized domains of physical activity are based on the literature and expert views that also reflect children's experiences and understanding providing a basis for pediatric self-report instruments. PMID:25251789

  9. Development and evaluation of an active instructional framework for undergraduate biology education

    NASA Astrophysics Data System (ADS)

    Lysne, Steven John

    The practice of science education in American colleges and universities is changing and the role of faculty is changing as well. There is momentum in higher education to transform our instruction and do a better job at supporting more students' success in science and engineering programs. New teaching approaches are transforming undergraduate science instruction and new research demonstrates that these new approaches are more engaging for students, result in greater achievement, and create more positive attitudes toward science careers. Additionally, teaching scholars have described a paradigm shift toward placing the burden of content coverage on students which allows more time for in-class activities such as discussion and problem solving. Teaching faculty have been asked to redesign their courses and rebrand themselves as facilitators of student learning, rather than purveyors of information, to improve student engagement, achievement, and attitudes. This dissertation is a critical evaluation of both the assumption that active learning improves student achievement and knowledge retention and my own assumptions regarding science education research and my students' resiliency. This dissertation is a collection of research articles, published or in preparation, presenting the chronological development (Chapters 2 and 3) and evaluation (Chapters 4 and 5) of an active instructional model for undergraduate biology instruction. Chapters 1 and 6.provide a broad introduction and summary, respectively. Chapter 2 is an exploration of student engagement through interviews with a variety of students. From these interviews I identified several themes that students felt were important, and science instructors need to address, including the place where learning happens and strategies for better engaging students. Chapter 3 presents a review of the science education literature broadly and more focused review on the how students learn and how faculty teach. Consistent with what

  10. Indicators Developed to Evaluate the International Framework Convention on Tobacco Control in Iran; A Grounded Theory Study

    PubMed Central

    Sarrafzadegan, Nizal; Rabiei, Katayoun; Abedi, Heidarali; Kelishadi, Roya; Fereydoun Mohaseli, Khadijeh; Alavi, Mousa; Roohafza, Hamidreza

    2014-01-01

    This study aimed to develop indicators for evaluating the implementation of The Framework Convention on Tobacco Control (FCTC) in Iran. We used the “grounded theory” framework. Totally, 265 policy-makers, stakeholders, and community members were recruited by purposeful sampling in 2008. After analyzing the gathered data, 251 indicators, including 82 indicators as “applied indicators”, were derived from second-level codes for three groups. A suitable evaluation questionnaire can be designed based on the extracted indicators for policy makers, stakeholders, and the community to follow the implementation of the FCTC in Iran. PMID:24753645

  11. Density functional theory meta-GGA + U study of water incorporation in the metal-organic framework material Cu-BTC

    NASA Astrophysics Data System (ADS)

    Cockayne, Eric; Nelson, Eric B.

    2015-07-01

    Water absorption in the metal-organic framework (MOF) material Cu-BTC, up to a concentration of 3.5 H2O per Cu ion, is studied via density functional theory at the meta-GGA + U level. The stable arrangements of water molecules show chains of hydrogen-bonded water molecules and a tendency to form closed cages at high concentration. Water clusters are stabilized primarily by a combination of water-water hydrogen bonding and Cu-water oxygen interactions. Stability is further enhanced by van der Waals interactions, electric field enhancement of water-water bonding, and hydrogen bonding of water to framework oxygens. We hypothesize that the tendency to form such stable clusters explains the particularly strong affinity of water to Cu-BTC and related MOFs with exposed metal sites.

  12. Density functional theory meta-GGA + U study of water incorporation in the metal-organic framework material Cu-BTC.

    PubMed

    Cockayne, Eric; Nelson, Eric B

    2015-07-14

    Water absorption in the metal-organic framework (MOF) material Cu-BTC, up to a concentration of 3.5 H2O per Cu ion, is studied via density functional theory at the meta-GGA + U level. The stable arrangements of water molecules show chains of hydrogen-bonded water molecules and a tendency to form closed cages at high concentration. Water clusters are stabilized primarily by a combination of water-water hydrogen bonding and Cu-water oxygen interactions. Stability is further enhanced by van der Waals interactions, electric field enhancement of water-water bonding, and hydrogen bonding of water to framework oxygens. We hypothesize that the tendency to form such stable clusters explains the particularly strong affinity of water to Cu-BTC and related MOFs with exposed metal sites. PMID:26178120

  13. PdHx entrapped in covalent triazine framework modulates selectivity in glycerol oxidation [Modulation of palladium activity and stability by a covalent triazine framework

    DOE PAGESBeta

    Chan-Thaw, Carine E.; Villa, Alberto; Wang, Di; Biroli, Alessio; Veith, Gabriel M; Thomas, Arne; Prati, Laura

    2015-06-25

    The confinement of a Pd nanoparticle within a nitrogen-containing covalent triazine framework (CTF) material was investigated to understand if the highly tunable CTF chemistry mediates the Pd catalytic properties through an ensemble effect with the CTF nitrogen atoms or a confinement effect within the CTF pores. The results surprisingly demonstrate that the CTF stabilizes the formation of 2.6 nm PdHx particles within the pores. These PdHx particles are very active for the liquid phase oxidation of glycerol due to the in situ formation of H2O2 which catalytically promotes the initial C-C cleavage. In addition the confined particles are stable overmore » many catalytic cycles whereas nanoparticles trapped outside of the pores loose activity rapidly. These results indicate that there is the potential to tune the CTF chemistry to significantly modify the chemistry of the catalytic metals.« less

  14. PdHx entrapped in covalent triazine framework modulates selectivity in glycerol oxidation [Modulation of palladium activity and stability by a covalent triazine framework

    SciTech Connect

    Chan-Thaw, Carine E.; Villa, Alberto; Wang, Di; Biroli, Alessio; Veith, Gabriel M; Thomas, Arne; Prati, Laura

    2015-06-25

    The confinement of a Pd nanoparticle within a nitrogen-containing covalent triazine framework (CTF) material was investigated to understand if the highly tunable CTF chemistry mediates the Pd catalytic properties through an ensemble effect with the CTF nitrogen atoms or a confinement effect within the CTF pores. The results surprisingly demonstrate that the CTF stabilizes the formation of 2.6 nm PdHx particles within the pores. These PdHx particles are very active for the liquid phase oxidation of glycerol due to the in situ formation of H2O2 which catalytically promotes the initial C-C cleavage. In addition the confined particles are stable over many catalytic cycles whereas nanoparticles trapped outside of the pores loose activity rapidly. These results indicate that there is the potential to tune the CTF chemistry to significantly modify the chemistry of the catalytic metals.

  15. The Theory of Transactional Distance as a Framework for the Analysis of Computer-Aided Teaching of Geometry

    ERIC Educational Resources Information Center

    Papadopoulos, Ioannis; Dagdilelis, Vassilios

    2006-01-01

    In this paper, difficulties of students in the case of computer-mediated teaching of geometry in a traditional classroom are considered within the framework of "transactional distance", a concept well known in distance education. The main interest of this paper is to record and describe in detail the different forms of "distance" during students'…

  16. Using behavioural activation in the treatment of depression: a control theory perspective.

    PubMed

    McEvoy, P; Law, A; Bates, R; Hylton, K; Mansell, W

    2013-12-01

    Behavioural activation is an intervention that can be used to counteract the typical patterns of withdrawal, avoidance and inactivity that characterize depression. This paper examines the processes of change that may occur during behavioural activation from the perspective of control theory. Some of the key concepts that are associated with control theory are introduced and the process of change that may occur during behavioural activation is illustrated using two case studies. The case studies provide anecdotal evidence which supports the hypothesis that the effective implementation of behavioural activation may depend upon clients being able to retain or regain the sense of control that they value. The differences between a control-theory-based approach and more orthodox behavioural and cognitive approaches are highlighted and the implications of these differences are discussed. Flexible approaches that are informed by control theory, may offer a useful alternative to the more established behavioural and cognitive approaches towards behavioural activation. PMID:23240823

  17. Existential Threat or Dissociative Response? Examining Defensive Avoidance of Point-of-Care Testing Devices Through a Terror Management Theory Framework.

    PubMed

    Dunne, Simon; Gallagher, Pamela; Matthews, Anne

    2015-01-01

    Using a terror management theory framework, this study investigated if providing mortality reminders or self-esteem threats would lead participants to exhibit avoidant responses toward a point-of-care testing device for cardiovascular disease risk and if the nature of the device served to diminish the existential threat of cardiovascular disease. One hundred and twelve participants aged 40-55 years completed an experimental questionnaire. Findings indicated that participants were not existentially threatened by established terror management methodologies, potentially because of cross-cultural variability toward such methodologies. Highly positive appraisals of the device also suggest that similar technologies may beneficially affect the uptake of screening behaviors. PMID:24972015

  18. Screening for high-spin metal organic frameworks (MOFs): density functional theory study on DUT-8(M1,M2) (with Mi = V,…,Cu).

    PubMed

    Schwalbe, Sebastian; Trepte, Kai; Seifert, Gotthard; Kortus, Jens

    2016-03-01

    We present a first principles study of low-spin (LS)/high-spin (HS) screening for 3d metal centers in the metal organic framework (MOF) DUT-8(Ni). Various density functional theory (DFT) codes have been used to evaluate numerical and DFT related errors. We compare highly accurate all-electron implementations with the widely used plane wave approach. We present electronically and magnetically stable DUT-8(Ni) HS secondary building units (SBUs). In this work we show how to tune the magnetic and electronic properties of the original SBU only by changing the metal centers. PMID:26922864

  19. Positioning activated carbon amendment technologies in a novel framework for sediment management.

    PubMed

    Kupryianchyk, Darya; Rakowska, Magdalena I; Reible, Danny; Harmsen, Joop; Cornelissen, Gerard; van Veggel, Marc; Hale, Sarah E; Grotenhuis, Tim; Koelmans, Albert A

    2015-04-01

    Contaminated sediments can pose serious threats to human health and the environment by acting as a source of toxic chemicals. The amendment of contaminated sediments with strong sorbents like activated C (AC) is a rapidly developing strategy to manage contaminated sediments. To date, a great deal of attention has been paid to the technical and ecological features and implications of sediment remediation with AC, although science in this field still is rapidly evolving. This article aims to provide an update on the recent literature on these features, and provides a comparison of sediment remediation with AC to other sediment management options, emphasizing their full-scale application. First, a qualitative overview of advantages of current alternatives to remediate contaminated sediments is presented. Subsequently, AC treatment technology is critically reviewed, including current understanding of the effectiveness and ecological safety for the use of AC in natural systems. Finally, this information is used to provide a novel framework for supporting decisions concerning sediment remediation and beneficial reuse. PMID:25641867

  20. Electronic origins of photocatalytic activity in d0 metal organic frameworks

    PubMed Central

    Nasalevich, Maxim A.; Hendon, Christopher H.; Santaclara, Jara G.; Svane, Katrine; van der Linden, Bart; Veber, Sergey L.; Fedin, Matvey V.; Houtepen, Arjan J.; van der Veen, Monique A.; Kapteijn, Freek; Walsh, Aron; Gascon, Jorge

    2016-01-01

    Metal-organic frameworks (MOFs) containing d0 metals such as NH2-MIL-125(Ti), NH2-UiO-66(Zr) and NH2-UiO-66(Hf) are among the most studied MOFs for photocatalytic applications. Despite structural similarities, we demonstrate that the electronic properties of these MOFs are markedly different. As revealed by quantum chemistry, EPR measurements and transient absorption spectroscopy, the highest occupied and lowest unoccupied orbitals of NH2-MIL-125(Ti) promote a long lived ligand-to-metal charge transfer upon photoexcitation, making this material suitable for photocatalytic applications. In contrast, in case of UiO materials, the d-orbitals of Zr and Hf, are too low in binding energy and thus cannot overlap with the π* orbital of the ligand, making both frontier orbitals localized at the organic linker. This electronic reconfiguration results in short exciton lifetimes and diminishes photocatalytic performance. These results highlight the importance of orbital contributions at the band edges and delineate future directions in the development of photo-active hybrid solids. PMID:27020767

  1. Electronic origins of photocatalytic activity in d0 metal organic frameworks

    NASA Astrophysics Data System (ADS)

    Nasalevich, Maxim A.; Hendon, Christopher H.; Santaclara, Jara G.; Svane, Katrine; van der Linden, Bart; Veber, Sergey L.; Fedin, Matvey V.; Houtepen, Arjan J.; van der Veen, Monique A.; Kapteijn, Freek; Walsh, Aron; Gascon, Jorge

    2016-03-01

    Metal-organic frameworks (MOFs) containing d0 metals such as NH2-MIL-125(Ti), NH2-UiO-66(Zr) and NH2-UiO-66(Hf) are among the most studied MOFs for photocatalytic applications. Despite structural similarities, we demonstrate that the electronic properties of these MOFs are markedly different. As revealed by quantum chemistry, EPR measurements and transient absorption spectroscopy, the highest occupied and lowest unoccupied orbitals of NH2-MIL-125(Ti) promote a long lived ligand-to-metal charge transfer upon photoexcitation, making this material suitable for photocatalytic applications. In contrast, in case of UiO materials, the d-orbitals of Zr and Hf, are too low in binding energy and thus cannot overlap with the π* orbital of the ligand, making both frontier orbitals localized at the organic linker. This electronic reconfiguration results in short exciton lifetimes and diminishes photocatalytic performance. These results highlight the importance of orbital contributions at the band edges and delineate future directions in the development of photo-active hybrid solids.

  2. Electronic origins of photocatalytic activity in d0 metal organic frameworks.

    PubMed

    Nasalevich, Maxim A; Hendon, Christopher H; Santaclara, Jara G; Svane, Katrine; van der Linden, Bart; Veber, Sergey L; Fedin, Matvey V; Houtepen, Arjan J; van der Veen, Monique A; Kapteijn, Freek; Walsh, Aron; Gascon, Jorge

    2016-01-01

    Metal-organic frameworks (MOFs) containing d(0) metals such as NH2-MIL-125(Ti), NH2-UiO-66(Zr) and NH2-UiO-66(Hf) are among the most studied MOFs for photocatalytic applications. Despite structural similarities, we demonstrate that the electronic properties of these MOFs are markedly different. As revealed by quantum chemistry, EPR measurements and transient absorption spectroscopy, the highest occupied and lowest unoccupied orbitals of NH2-MIL-125(Ti) promote a long lived ligand-to-metal charge transfer upon photoexcitation, making this material suitable for photocatalytic applications. In contrast, in case of UiO materials, the d-orbitals of Zr and Hf, are too low in binding energy and thus cannot overlap with the π* orbital of the ligand, making both frontier orbitals localized at the organic linker. This electronic reconfiguration results in short exciton lifetimes and diminishes photocatalytic performance. These results highlight the importance of orbital contributions at the band edges and delineate future directions in the development of photo-active hybrid solids. PMID:27020767

  3. Towards a common framework for assessing the activity and associations of groups who sexually abuse children

    PubMed Central

    Cockbain, Ella; Brayley, Helen; Sullivan, Joe

    2013-01-01

    Extensive social psychological research emphasises the importance of groups in shaping individuals’ thoughts and actions. Within the child sexual abuse (CSA) literature criminal organisation has been largely overlooked, with some key exceptions. This research was a novel collaboration between academia and the UK's Child Exploitation and Online Protection Centre (CEOP). Starting from the premise that the group is, in itself, a form of social situation affecting abuse, it offers the first systematic situational analysis of CSA groups. In-depth behavioural data from a small sample of convicted CSA group-offenders (n = 3) were analysed qualitatively to identify factors and processes underpinning CSA groups’ activities and associations: group formation, evolution, identity and resources. The results emphasise CSA groups’ variability, fluidity and dynamism. The foundations of a general framework are proposed for researching and assessing CSA groups and designing effective interventions. It is hoped that this work will stimulate discussion and development in this long-neglected area of CSA, helping to build a coherent knowledge-base. PMID:26494978

  4. Preparation and Properties of Metal Organic Framework/Activated Carbon Composite Materials.

    PubMed

    Fleker, Ohad; Borenstein, Arie; Lavi, Ronit; Benisvy, Laurent; Ruthstein, Sharon; Aurbach, Doron

    2016-05-17

    Metal organic frameworks (MOFs) have unique properties that make them excellent candidates for many high-tech applications. Nevertheless, their nonconducting character is an obstacle to their practical utilization in electronic and energy systems. Using the familiar HKUST-1 MOF as a model, we present a new method of imparting electrical conductivity to otherwise nonconducting MOFs by preparing MOF nanoparticles within the conducting matrix of mesoporous activated carbon (AC). This composite material was studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), gas adsorption measurements, and electron paramagnetic resonance (EPR) spectroscopy. We show that MOF nanoparticles grown within the carbon matrix maintain their crystalline characteristics and their surface area. Surprisingly, as a result of the composition process, EPR measurements revealed a copper signal that had not yet been achieved. For the first time, we could analyze the complex EPR response of HKUST-1. We demonstrate the high conductivity of the MOF composite and discuss various factors that are responsible for these results. Finally, we present an optional application for using the conductive MOF composite as a high-performance electrode for pseudocapacitors. PMID:27104367

  5. Induced starburst and nuclear activity: Faith, facts, and theory

    NASA Technical Reports Server (NTRS)

    Shlosman, Isaac

    1990-01-01

    The problem of the origin of starburst and nuclear (nonstellar) activity in galaxies is reviewed. A physical understanding of the mechanism(s) that induce both types of activity requires one to address the following issues: (1) what is the source of fuel that powers starbursts and active galactic nuclei; and (2) how is it channeled towards the central regions of host galaxies? As a possible clue, the author examines the role of non-axisymmetric perturbations of galactic disks and analyzes their potential triggers. Global gravitational instabilities in the gas on scales approx. 100 pc appear to be crucial for fueling the active galactic nuclei.

  6. Inelastic Scattering of Identical Molecules within Framework of the Mixed Quantum/Classical Theory: Application to Rotational Excitations in H2 + H2.

    PubMed

    Semenov, Alexander; Babikov, Dmitri

    2016-06-01

    Theoretical foundation is laid out for description of permutation symmetry in the inelastic scattering processes that involve collisions of two identical molecules, within the framework of the mixed quantum/classical theory (MQCT). In this approach, the rotational (and vibrational) states of two molecules are treated quantum-mechanically, whereas their translational motion (responsible for scattering) is treated classically. This theory is applied to H2 + H2 system, and the state-to-state transition cross sections are compared versus those obtained from the full-quantum calculations and experimental results from the literature. Good agreement is found in all cases. It is also found that results of MQCT, where the Coriolis coupling is included classically, are somewhat closer to exact full-quantum results than results of the other approximate quantum methods, where those coupling terms are neglected. These new developments allow applications of MQCT to a broad variety of molecular systems and processes. PMID:27187769

  7. Socio-Cultural Context for Online Learning: A Case Study Viewed from Activity Theory Perspective

    ERIC Educational Resources Information Center

    Liu, Xiaojing

    2004-01-01

    The complexities of digital age pose challenge to existing instruction technology theory as it applies to a distance learning environment. Through the lens of Activity Theory, this study takes a broad picture of an online course and examines the socio-cultural factors affecting the success of a distance course as well as their complex…

  8. Job Search and Social Cognitive Theory: The Role of Career-Relevant Activities

    ERIC Educational Resources Information Center

    Zikic, Jelena; Saks, Alan M.

    2009-01-01

    Social cognitive theory was used to explain the relationships between career-relevant activities (environmental and self career exploration, career resources, and training), self-regulatory variables (job search self-efficacy and job search clarity), variables from the Theory of Planned Behavior (job search attitude, subjective norm, job search…

  9. Presenting Theoretical Ideas Prior to Inquiry Activities Fosters Theory-Level Knowledge

    ERIC Educational Resources Information Center

    Wecker, Christof; Rachel, Alexander; Heran-Dörr, Eva; Waltner, Christine; Wiesner, Hartmut; Fischer, Frank

    2013-01-01

    In the course of inquiry activities similar to those of real scientists, learners are supposed to develop knowledge both on the level of observable phenomena and on the level of explanatory theories. However, some theories involve theoretical entities (e.g., "Weiss domains") that cannot be observed directly and therefore may be hard to…

  10. Development and Evaluation of a Theory-Based Physical Activity Guidebook for Breast Cancer Survivors

    ERIC Educational Resources Information Center

    Vallance, Jeffrey K.; Courneya, Kerry S.; Taylor, Lorian M.; Plotnikoff, Ronald C.; Mackey, John R.

    2008-01-01

    This study's objective was to develop and evaluate the suitability and appropriateness of a theory-based physical activity (PA) guidebook for breast cancer survivors. Guidebook content was constructed based on the theory of planned behavior (TPB) using salient exercise beliefs identified by breast cancer survivors in previous research. Expert…

  11. Cultural-Historical Activity Theory: Vygotsky's Forgotten and Suppressed Legacy and Its Implication for Mathematics Education

    ERIC Educational Resources Information Center

    Roth, Wolff-Michael

    2012-01-01

    Cultural-historical activity theory--with historical roots in dialectical materialism and the social psychology to which it has given rise--has experienced exponential growth in its acceptance by scholars interested in understanding knowing and learning writ large. In education, this theory has constituted something like a well kept secret that is…

  12. A porous metal-organic framework containing multiple active Cu(2+) sites for highly efficient cross dehydrogenative coupling reaction.

    PubMed

    Zhu, Shu-Lan; Ou, Sha; Zhao, Min; Shen, Hong; Wu, Chuan-De

    2015-02-01

    A novel 3D porous metal-organic framework was constructed from imidazole carboxylate linkers and copper(ii) nodes, which in situ generates multiple active Cu(II) sites in the nanosized channel walls for highly efficient cross dehydrogenative coupling reaction between 1,2,3,4-tetrahydroisoquinoline derivatives and nitroalkanes that are superior to the simple copper salts. PMID:25515613

  13. Health Education and Physical Education (Healthy, Active Living). Grades 5 and 9. Assessment Annotations for the Curriculum Frameworks.

    ERIC Educational Resources Information Center

    Missouri State Dept. of Elementary and Secondary Education, Jefferson City.

    This document provides supplemental assessment information to "Missouri's Framework for Curriculum Development in Health Education and Physical Education (Healthy, Active Living) K-12." The assessment annotations found in the third column of this document are intended to provide information for administrators, curriculum directors, and teachers…

  14. Implicit theories about willpower predict the activation of a rest goal following self-control exertion.

    PubMed

    Job, Veronika; Bernecker, Katharina; Miketta, Stefanie; Friese, Malte

    2015-10-01

    Past research indicates that peoples' implicit theories about the nature of willpower moderate the ego-depletion effect. Only people who believe or were led to believe that willpower is a limited resource (limited-resource theory) showed lower self-control performance after an initial demanding task. As of yet, the underlying processes explaining this moderating effect by theories about willpower remain unknown. Here, we propose that the exertion of self-control activates the goal to preserve and replenish mental resources (rest goal) in people with a limited-resource theory. Five studies tested this hypothesis. In Study 1, individual differences in implicit theories about willpower predicted increased accessibility of a rest goal after self-control exertion. Furthermore, measured (Study 2) and manipulated (Study 3) willpower theories predicted an increased preference for rest-conducive objects. Finally, Studies 4 and 5 provide evidence that theories about willpower predict actual resting behavior: In Study 4, participants who held a limited-resource theory took a longer break following self-control exertion than participants with a nonlimited-resource theory. Longer resting time predicted decreased rest goal accessibility afterward. In Study 5, participants with an induced limited-resource theory sat longer on chairs in an ostensible product-testing task when they had engaged in a task requiring self-control beforehand. This research provides consistent support for a motivational shift toward rest after self-control exertion in people holding a limited-resource theory about willpower. PMID:26075793

  15. What graph theory actually tells us about resting state interictal MEG epileptic activity

    PubMed Central

    Niso, Guiomar; Carrasco, Sira; Gudín, María; Maestú, Fernando; del-Pozo, Francisco; Pereda, Ernesto

    2015-01-01

    Graph theory provides a useful framework to study functional brain networks from neuroimaging data. In epilepsy research, recent findings suggest that it offers unique insight into the fingerprints of this pathology on brain dynamics. Most studies hitherto have focused on seizure activity during focal epilepsy, but less is known about functional epileptic brain networks during interictal activity in frontal focal and generalized epilepsy. Besides, it is not clear yet which measures are most suitable to characterize these networks. To address these issues, we recorded magnetoencephalographic (MEG) data using two orthogonal planar gradiometers from 45 subjects from three groups (15 healthy controls (7 males, 24 ± 6 years), 15 frontal focal (8 male, 32 ± 16 years) and 15 generalized epileptic (6 male, 27 ± 7 years) patients) during interictal resting state with closed eyes. Then, we estimated the total and relative spectral power of the largest principal component of the gradiometers, and the degree of phase synchronization between each sensor site in the frequency range [0.5–40 Hz]. We further calculated a comprehensive battery of 15 graph-theoretic measures and used the affinity propagation clustering algorithm to elucidate the minimum set of them that fully describe these functional brain networks. The results show that differences in spectral power between the control and the other two groups have a distinctive pattern: generalized epilepsy presents higher total power for all frequencies except the alpha band over a widespread set of sensors; frontal focal epilepsy shows higher relative power in the beta band bilaterally in the fronto-central sensors. Moreover, all network indices can be clustered into three groups, whose exemplars are the global network efficiency, the eccentricity and the synchronizability. Again, the patterns of differences were clear: the brain network of the generalized epilepsy patients presented greater efficiency and lower

  16. What graph theory actually tells us about resting state interictal MEG epileptic activity.

    PubMed

    Niso, Guiomar; Carrasco, Sira; Gudín, María; Maestú, Fernando; Del-Pozo, Francisco; Pereda, Ernesto

    2015-01-01

    Graph theory provides a useful framework to study functional brain networks from neuroimaging data. In epilepsy research, recent findings suggest that it offers unique insight into the fingerprints of this pathology on brain dynamics. Most studies hitherto have focused on seizure activity during focal epilepsy, but less is known about functional epileptic brain networks during interictal activity in frontal focal and generalized epilepsy. Besides, it is not clear yet which measures are most suitable to characterize these networks. To address these issues, we recorded magnetoencephalographic (MEG) data using two orthogonal planar gradiometers from 45 subjects from three groups (15 healthy controls (7 males, 24 ± 6 years), 15 frontal focal (8 male, 32 ± 16 years) and 15 generalized epileptic (6 male, 27 ± 7 years) patients) during interictal resting state with closed eyes. Then, we estimated the total and relative spectral power of the largest principal component of the gradiometers, and the degree of phase synchronization between each sensor site in the frequency range [0.5-40 Hz]. We further calculated a comprehensive battery of 15 graph-theoretic measures and used the affinity propagation clustering algorithm to elucidate the minimum set of them that fully describe these functional brain networks. The results show that differences in spectral power between the control and the other two groups have a distinctive pattern: generalized epilepsy presents higher total power for all frequencies except the alpha band over a widespread set of sensors; frontal focal epilepsy shows higher relative power in the beta band bilaterally in the fronto-central sensors. Moreover, all network indices can be clustered into three groups, whose exemplars are the global network efficiency, the eccentricity and the synchronizability. Again, the patterns of differences were clear: the brain network of the generalized epilepsy patients presented greater efficiency and lower

  17. Tried and True: Self-Regulation Theory as a Guiding Framework for Teaching Parents Diabetes Education Using Human Patient Simulation

    PubMed Central

    Sullivan-Bolyai, Susan; Johnson, Kimberly; Cullen, Karen; Hamm, Terry; Bisordi, Jean; Blaney, Kathleen; Maguire, Laura; Melkus, Gail

    2014-01-01

    Parents become emotionally upset when learning their child has Type 1 Diabetes, yet they are expected to quickly learn functional diabetes management. The purpose of this article is to describe the application of Self-Regulation theory to guide a family-focused education intervention using human patient simulation to enhance the initial education of parents in diabetes management. A brief description is provided of the intervention framed by Self-Regulation theory. Based on the literature, we describe the educational vignettes used based on Self-Regulation in the randomized controlled trial entitled Parent Education Through Simulation-Diabetes. Examples of theory-in-practice will be illustrated by parental learning responses to this alternative educational innovation. PMID:25365286

  18. Web-Based Virtual Patients in Nursing Education: Development and Validation of Theory-Anchored Design and Activity Models

    PubMed Central

    2014-01-01

    Background Research has shown that nursing students find it difficult to translate and apply their theoretical knowledge in a clinical context. Virtual patients (VPs) have been proposed as a learning activity that can support nursing students in their learning of scientific knowledge and help them integrate theory and practice. Although VPs are increasingly used in health care education, they still lack a systematic consistency that would allow their reuse outside of their original context. There is therefore a need to develop a model for the development and implementation of VPs in nursing education. Objective The aim of this study was to develop and evaluate a virtual patient model optimized to the learning and assessment needs in nursing education. Methods The process of modeling started by reviewing theoretical frameworks reported in the literature and used by practitioners when designing learning and assessment activities. The Outcome-Present State Test (OPT) model was chosen as the theoretical framework. The model was then, in an iterative manner, developed and optimized to the affordances of virtual patients. Content validation was performed with faculty both in terms of the relevance of the chosen theories but also its applicability in nursing education. The virtual patient nursing model was then instantiated in two VPs. The students’ perceived usefulness of the VPs was investigated using a questionnaire. The result was analyzed using descriptive statistics. Results A virtual patient Nursing Design Model (vpNDM) composed of three layers was developed. Layer 1 contains the patient story and ways of interacting with the data, Layer 2 includes aspects of the iterative process of clinical reasoning, and finally Layer 3 includes measurable outcomes. A virtual patient Nursing Activity Model (vpNAM) was also developed as a guide when creating VP-centric learning activities. The students perceived the global linear VPs as a relevant learning activity for the

  19. Immobilizing highly catalytically active Pt nanoparticles inside the pores of metal-organic framework: a double solvents approach.

    PubMed

    Aijaz, Arshad; Karkamkar, Abhi; Choi, Young Joon; Tsumori, Nobuko; Rönnebro, Ewa; Autrey, Tom; Shioyama, Hiroshi; Xu, Qiang

    2012-08-29

    Ultrafine Pt nanoparticles were successfully immobilized inside the pores of a metal-organic framework, MIL-101, without aggregation of Pt nanoparticles on the external surfaces of framework by using a "double solvents" method. TEM and electron tomographic measurements clearly demonstrated the uniform three-dimensional distribution of the ultrafine Pt NPs throughout the interior cavities of MIL-101. The resulting Pt@MIL-101 composites represent the first highly active MOF-immobilized metal nanocatalysts for catalytic reactions in all three phases: liquid-phase ammonia borane hydrolysis, solid-phase ammonia borane thermal dehydrogenation, and gas-phase CO oxidation. PMID:22888976

  20. Teachers' Views on Understanding Evolutionary Theory: A PCK-Study in the Framework of the ERTE-Model

    ERIC Educational Resources Information Center

    van Dijk, Esther M.

    2009-01-01

    The study of Pedagogical Content Knowledge (PCK) that is presented in this paper aims to obtain an impression of teachers' knowledge and beliefs concerning teaching evolutionary theory. The starting point of this project was the development of the Educational Reconstruction for Teacher Education model (ERTE). The PCK-study shows that teachers'…

  1. The Inclusion of Children with ASD: Using the Theory of Planned Behaviour as a Theoretical Framework to Explore Peer Attitudes

    ERIC Educational Resources Information Center

    Freitag, Sara; Dunsmuir, Sandra

    2015-01-01

    This study used the Theory of Planned Behaviour to explore the attitudes, behavioural intentions and behaviour of 318 mainstream primary school children in an urban East London borough towards peers with Autism Spectrum Disorders (ASD). Pupils were presented with a vignette about a hypothetical peer with ASD then completed self-report…

  2. Integrating Theory and Practice to Increase Scientific Workforce Diversity: A Framework for Career Development in Graduate Research Training

    ERIC Educational Resources Information Center

    Byars-Winston, Angela; Gutierrez, Belinda; Topp, Sharon; Carnes, Molly

    2011-01-01

    Few, if any, educational interventions intended to increase underrepresented minority (URM) graduate students in biological and behavioral sciences are informed by theory and research on career persistence. Training and Education to Advance Minority Scholars in Science (TEAM-Science) is a program funded by the National Institute of General Medical…

  3. "Module 9": A New Course to Help Students Develop Interdisciplinary Projects Using the Framework of Experiential Learning Theory

    ERIC Educational Resources Information Center

    Canboy, Basak; Montalvo, Adolfo; Buganza, M. Carmen; Emmerling, Robert J.

    2016-01-01

    This paper offers an example of how to introduce student-centred knowledge creation and competency development in a systematic way into a master's programme. The curriculum of a new course called Module 9 was framed according to experiential learning theory. While student teams work on self-selected projects, their learning processes are…

  4. Relational-Cultural Theory: A Framework for Relational Competencies and Movement in Group Work with Female Adolescents

    ERIC Educational Resources Information Center

    Cannon, Kristi B.; Hammer, Tonya R.; Reicherzer, Stacee; Gilliam, Billie J.

    2012-01-01

    Relational-cultural theory (RCT) is an evolving feminist model of human development that places emphasis on growth-fostering relationships as building blocks for wellness. This article demonstrates the use of RCT in addressing relational aggression, including cyberbullying, in counseling a group of adolescent girls. The group counselor's…

  5. Levels of Reconstruction as Complementarity in Mixed Methods Research: A Social Theory-Based Conceptual Framework for Integrating Qualitative and Quantitative Research

    PubMed Central

    Carroll, Linda J.; Rothe, J. Peter

    2010-01-01

    Like other areas of health research, there has been increasing use of qualitative methods to study public health problems such as injuries and injury prevention. Likewise, the integration of qualitative and quantitative research (mixed-methods) is beginning to assume a more prominent role in public health studies. Likewise, using mixed-methods has great potential for gaining a broad and comprehensive understanding of injuries and their prevention. However, qualitative and quantitative research methods are based on two inherently different paradigms, and their integration requires a conceptual framework that permits the unity of these two methods. We present a theory-driven framework for viewing qualitative and quantitative research, which enables us to integrate them in a conceptually sound and useful manner. This framework has its foundation within the philosophical concept of complementarity, as espoused in the physical and social sciences, and draws on Bergson’s metaphysical work on the ‘ways of knowing’. Through understanding how data are constructed and reconstructed, and the different levels of meaning that can be ascribed to qualitative and quantitative findings, we can use a mixed-methods approach to gain a conceptually sound, holistic knowledge about injury phenomena that will enhance our development of relevant and successful interventions. PMID:20948937

  6. Shared Investment Projects and Forecasting Errors: Setting Framework Conditions for Coordination and Sequencing Data Quality Activities

    PubMed Central

    Leitner, Stephan; Brauneis, Alexander; Rausch, Alexandra

    2015-01-01

    In this paper, we investigate the impact of inaccurate forecasting on the coordination of distributed investment decisions. In particular, by setting up a computational multi-agent model of a stylized firm, we investigate the case of investment opportunities that are mutually carried out by organizational departments. The forecasts of concern pertain to the initial amount of money necessary to launch and operate an investment opportunity, to the expected intertemporal distribution of cash flows, and the departments’ efficiency in operating the investment opportunity at hand. We propose a budget allocation mechanism for coordinating such distributed decisions The paper provides guidance on how to set framework conditions, in terms of the number of investment opportunities considered in one round of funding and the number of departments operating one investment opportunity, so that the coordination mechanism is highly robust to forecasting errors. Furthermore, we show that—in some setups—a certain extent of misforecasting is desirable from the firm’s point of view as it supports the achievement of the corporate objective of value maximization. We then address the question of how to improve forecasting quality in the best possible way, and provide policy advice on how to sequence activities for improving forecasting quality so that the robustness of the coordination mechanism to errors increases in the best possible way. At the same time, we show that wrong decisions regarding the sequencing can lead to a decrease in robustness. Finally, we conduct a comprehensive sensitivity analysis and prove that—in particular for relatively good forecasters—most of our results are robust to changes in setting the parameters of our multi-agent simulation model. PMID:25803736

  7. Mechanism of electrochemical lithiation of a metal-organic framework without redox-active nodes.

    PubMed

    Tang, Bohejin; Huang, Shuping; Fang, Yuan; Hu, Jinbo; Malonzo, Camille; Truhlar, Donald G; Stein, Andreas

    2016-05-21

    Metal-organic frameworks (MOFs) have many potential uses for separations, storage, and catalysis, but their use as intercalation hosts for batteries has been scarce. In this article, we examine the mechanism of Li insertion in a MOF to provide guidance to future design efforts in this area. As a model system, we choose UiO-66, a MOF with the formula (Zr6O4(OH)4)4(1,4-benzenedicarboxylate)6, as an electrode material for lithium-ion batteries; this MOF is of special interest because the zirconium is not redox active. We report both quantum mechanical characterization of the mechanism and experimental studies in which the material is synthesized as nanoparticles to reduce diffusion lengths for lithium ions and increase the contact area with a conductive carbon phase. The calculated changes in the IR spectra of UiO-66 and lithiated UiO-66 are consistent with the experimental FTIR results. We found experimentally that this MOF can maintain a specific discharge capacity of at least 118 mAh/g for 30 lithiation and delithiation cycles at a rate of C/5, exhibiting good cyclability. Density functional electronic structure calculations show that the charge transfer during lithiation is mainly from Li to node oxygens and carboxylate oxygens, that is, it involves anions rather than cations or aromatic rings, and they provide a mechanistic understanding of the potential for increased Li capacity because the theoretical capacity of UiO-66 with Li at the oxygens in the metal oxide nodes and the carboxylate linkers is more than 400 mAh/g. The lithiation process greatly decreases the bandgap of UiO-66, which is expected to increase its electronic conductivity. The electrode material was also characterized by X-ray diffraction and scanning electron microscopy, which were consistent in confirming that smaller particle sizes were obtained in lower-temperature syntheses. PMID:27208960

  8. Mechanism of electrochemical lithiation of a metal-organic framework without redox-active nodes

    NASA Astrophysics Data System (ADS)

    Tang, Bohejin; Huang, Shuping; Fang, Yuan; Hu, Jinbo; Malonzo, Camille; Truhlar, Donald G.; Stein, Andreas

    2016-05-01

    Metal-organic frameworks (MOFs) have many potential uses for separations, storage, and catalysis, but their use as intercalation hosts for batteries has been scarce. In this article, we examine the mechanism of Li insertion in a MOF to provide guidance to future design efforts in this area. As a model system, we choose UiO-66, a MOF with the formula (Zr6O4(OH)4)4(1,4-benzenedicarboxylate)6, as an electrode material for lithium-ion batteries; this MOF is of special interest because the zirconium is not redox active. We report both quantum mechanical characterization of the mechanism and experimental studies in which the material is synthesized as nanoparticles to reduce diffusion lengths for lithium ions and increase the contact area with a conductive carbon phase. The calculated changes in the IR spectra of UiO-66 and lithiated UiO-66 are consistent with the experimental FTIR results. We found experimentally that this MOF can maintain a specific discharge capacity of at least 118 mAh/g for 30 lithiation and delithiation cycles at a rate of C/5, exhibiting good cyclability. Density functional electronic structure calculations show that the charge transfer during lithiation is mainly from Li to node oxygens and carboxylate oxygens, that is, it involves anions rather than cations or aromatic rings, and they provide a mechanistic understanding of the potential for increased Li capacity because the theoretical capacity of UiO-66 with Li at the oxygens in the metal oxide nodes and the carboxylate linkers is more than 400 mAh/g. The lithiation process greatly decreases the bandgap of UiO-66, which is expected to increase its electronic conductivity. The electrode material was also characterized by X-ray diffraction and scanning electron microscopy, which were consistent in confirming that smaller particle sizes were obtained in lower-temperature syntheses.

  9. Shared investment projects and forecasting errors: setting framework conditions for coordination and sequencing data quality activities.

    PubMed

    Leitner, Stephan; Brauneis, Alexander; Rausch, Alexandra

    2015-01-01

    In this paper, we investigate the impact of inaccurate forecasting on the coordination of distributed investment decisions. In particular, by setting up a computational multi-agent model of a stylized firm, we investigate the case of investment opportunities that are mutually carried out by organizational departments. The forecasts of concern pertain to the initial amount of money necessary to launch and operate an investment opportunity, to the expected intertemporal distribution of cash flows, and the departments' efficiency in operating the investment opportunity at hand. We propose a budget allocation mechanism for coordinating such distributed decisions The paper provides guidance on how to set framework conditions, in terms of the number of investment opportunities considered in one round of funding and the number of departments operating one investment opportunity, so that the coordination mechanism is highly robust to forecasting errors. Furthermore, we show that-in some setups-a certain extent of misforecasting is desirable from the firm's point of view as it supports the achievement of the corporate objective of value maximization. We then address the question of how to improve forecasting quality in the best possible way, and provide policy advice on how to sequence activities for improving forecasting quality so that the robustness of the coordination mechanism to errors increases in the best possible way. At the same time, we show that wrong decisions regarding the sequencing can lead to a decrease in robustness. Finally, we conduct a comprehensive sensitivity analysis and prove that-in particular for relatively good forecasters-most of our results are robust to changes in setting the parameters of our multi-agent simulation model. PMID:25803736

  10. A framework of vertebra segmentation using the active shape model-based approach.

    PubMed

    Benjelloun, Mohammed; Mahmoudi, Saïd; Lecron, Fabian

    2011-01-01

    We propose a medical image segmentation approach based on the Active Shape Model theory. We apply this method for cervical vertebra detection. The main advantage of this approach is the application of a statistical model created after a training stage. Thus, the knowledge and interaction of the domain expert intervene in this approach. Our application allows the use of two different models, that is, a global one (with several vertebrae) and a local one (with a single vertebra). Two modes of segmentation are also proposed: manual and semiautomatic. For the manual mode, only two points are selected by the user on a given image. The first point needs to be close to the lower anterior corner of the last vertebra and the second near the upper anterior corner of the first vertebra. These two points are required to initialize the segmentation process. We propose to use the Harris corner detector combined with three successive filters to carry out the semiautomatic process. The results obtained on a large set of X-ray images are very promising. PMID:21826134

  11. Implicit theories of the body among college women: implications for physical activity.

    PubMed

    Lyons, Claire; Kaufman, Annette R; Rima, Brandi

    2015-09-01

    This study explored the relationship between implicit theories of the body (ITB) and self-reported physical activity. ITB are beliefs about the malleability of the body. Individuals may hold entity ITB (that body appearance is fixed) or incremental ITB (that body appearance can be changed). Female undergraduate students (N = 313) completed an online survey assessing ITB, physical activity, and discrepancy between actual and ideal body weight. Participants endorsing incremental ITB reported more physical activity. A significant ITB by weight discrepancy interaction emerged. Developing interventions targeting implicit theories of the body may be one way to increase physical activity. PMID:24271689

  12. The Effectiveness of WhatsApp Mobile Learning Activities Guided by Activity Theory on Students' Knowledge Management

    ERIC Educational Resources Information Center

    Barhoumi, Chokri

    2015-01-01

    This research paper explores the effectiveness of using mobile technologies to support a blended learning course titled Scientific Research Methods in Information Science. Specifically, it discusses the effects of WhatsApp mobile learning activities guided by activity theory on students' knowledge Management (KM). During the 2014 academic year,…

  13. Activity Theory and the Transformation of Pedagogic Practice

    ERIC Educational Resources Information Center

    Yamazumi, Katsuhiro

    2006-01-01

    Today, work and other societal practices are experiencing accelerating paradigm shifts from mass-production-based systems toward new systems based on networking between organizations, collaboration, and partnerships. This shift requires new paradigms in the fields of education, learning, and development. As human activity quickly changes to…

  14. Quantum Theory, Active Information and the Mind-Matter Problem

    NASA Astrophysics Data System (ADS)

    Pylkkänen, Paavo

    Bohm and Hiley suggest that a certain new type of active information plays a key objective role in quantum processes. This chapter discusses the implications of this suggestion to our understanding of the relation between the mental and the physical aspects of reality.

  15. Exploring Formative Assessment Using Cultural Historical Activity Theory

    ERIC Educational Resources Information Center

    Asghar, Mandy

    2013-01-01

    Formative assessment is a pedagogic practice that has been the subject of much research and debate, as to how it can be used most effectively to deliver enhanced student learning in the higher education setting. Often described as a complex concept it embraces activities that range from facilitating students understanding of assessment standards,…

  16. Institutionalizing Retention Activity: Toward a Theory-Based Model.

    ERIC Educational Resources Information Center

    Saunders, Martha Dunagin

    2003-01-01

    Examines Appreciative Inquiry, a relatively new approach to organizational change and growth, as a method for institutionalizing retention activity. Results of a case study in a college of arts and sciences suggest the method to be effective in creating a shared vision for the organization, energized participants, improved morale, and increased…

  17. To have or to be? A comparison of materialism-based theories and self-determination theory as explanatory frameworks of prejudice.

    PubMed

    Van Hiel, Alain; Cornelis, Ilse; Roets, Arne

    2010-06-01

    The present study aimed to delineate the psychological structure of materialism and intrinsic and extrinsic value pursuit. Moreover, we compared models based on self-determination theory (SDT), Fromm's marketing character, and Inglehart's theory of social change to account for racial prejudice. In a sample of undergraduate students (n=131) and adults (n=176) it was revealed that the extrinsic value pursuit Financial Success/Materialism could be distinguished from the extrinsic value scales Physical Appeal and Social Recognition, and Community Concern could be distinguished from the intrinsic value pursuit scales Self-acceptance and Affiliation. Moreover, Financial Success/Materialism and Community Concern were consistently and significantly related to prejudice, whereas the other SDT facet scales yielded weaker relationships with prejudice. Structural models based on SDT and Inglehart were not corroborated, but instead the present data supported a mediation model based on Fromm's work in which the effect of Community Concern was mediated by Financial Success/Materialism. Broader implications for SDT are critically assessed. PMID:20573135

  18. An assisted navigation training framework based on judgment theory using sparse and discrete human-machine interfaces.

    PubMed

    Lopes, Ana C; Nunes, Urbano

    2009-01-01

    This paper aims to present a new framework to train people with severe motor disabilities steering an assisted mobile robot (AMR), such as a powered wheelchair. Users with high level of motor disabilities are not able to use standard HMIs, which provide a continuous command signal (e. g. standard joystick). For this reason HMIs providing a small set of simple commands, which are sparse and discrete in time must be used (e. g. scanning interface, or brain computer interface), making very difficult to steer the AMR. In this sense, the assisted navigation training framework (ANTF) is designed to train users driving the AMR, in indoor structured environments, using this type of HMIs. Additionally it provides user characterization on steering the robot, which will later be used to adapt the AMR navigation system to human competence steering the AMR. A rule-based lens (RBL) model is used to characterize users on driving the AMR. Individual judgment performance choosing the best manoeuvres is modeled using a genetic-based policy capturing (GBPC) technique characterized to infer non-compensatory judgment strategies from human decision data. Three user models, at three different learning stages, using the RBL paradigm, are presented. PMID:19963849

  19. Catalytic activity of nuclease P1: Experiment and theory

    SciTech Connect

    Miller, J.H.; Falcone, J.M.; Shibata, M.; Box, H.C.

    1994-10-01

    Nuclease P1 from Penicillium citrinum is a zinc dependent glyco-enzyme that recognizes single stranded DNA and RNA as substrates and hydrolyzes the phosphate ester bond. Nuclease Pl seems to recognize particular conformations of the phosphodiester backbone and shows significant variation in the rate of hydrolytic activity depending upon which nucleosides are coupled by the phosphodiester bond. The efficiency of nuclease Pl in hydrolyzing the phosphodiester bonds of a substrate can be altered by modifications to one of the substrate bases induced by ionizing radiation or oxidative stress. Measurements have been made of the effect of several radiation induced lesions on the catalytic rate of nuclease Pl. A model of the structure of the enzyme has been constructed in order to better understand the binding and activity of this enzyme on various ssDNA substrates.

  20. Project Spectrum: Early Learning Activities. Project Zero Frameworks for Early Childhood Education, Volume 2.

    ERIC Educational Resources Information Center

    Chen, Jie-Qi, Ed.; Isberg, Emily, Ed.; Krechevsky, Mara, Ed.

    Project Spectrum is a collaborative research and development project that offers an alternative approach to assessment and curriculum development for preschool and early primary years. The project, based on Howard Gardner's multiple intelligences theory and David Henry Feldman's nonuniversal development theory, emphasizes observing children…

  1. Evolution of the Universe within the framework of the modified Jordan-Brans-Dicke theory: The role of the cosmological scalar

    NASA Astrophysics Data System (ADS)

    Chubaryan, Edvard; Avagyan, Roland; Harutunyan, Gohar; Kotanjyan, Anna

    2016-07-01

    Early and late stages of the cosmological expansion are considered on the base of the modified Jordan-Brans-Dicke (JBD) theory, under the assumption φ(y)=αH ^{n} (H is the Hubble constant, n is a parameter equal to four in the inflationary stage and one or two at late stages of the Universe evolution). At late stages, dynamical pattern is obtained with uniformly accelerated expansion for different values of σ (σ is the coupling constant between the gravitational and scalar fields). It is remarkable that for the limiting allowed value of α=9/(2σ) and for large σ, this variant of the theory is equivalent to the de Sitter model in the framework of the Einstein theory in the presence of a scalar field φ(y)=αH ^{2}. Therefore, the quasi exponential growth of the scale factor in the limiting case becomes purely exponential. Note that in the previously considered models the behavior of α was a power law. We also consider the inflationary regime with φ(y)=αH ^{4}. It is shown that in this case a model with slow rolling can be constructed.

  2. Unusual N-H activation of 2-aminopyrimidine: supramolecular assembly into an Ag(I) metal-organic framework.

    PubMed

    Liu, Fu-Ling; Xu, Zheng-Hu; Zhang, Xi-Ying; Wang, Xing-Po; Sun, Di

    2014-02-01

    A rare example of coordination at the amino group of NH2 pym (2-aminopyrimidine) relevant to N-H activation is described that leads to a novel Ag(I) -imide 3D metal-organic framework (MOF). The coordination of Ag(I) to NH2 pym produced an electron-withdrawing effect and thus increased its acidity, which facilitated the N-H activation and the subsequent formation of the Ag-imide bond. A cooperative metalation/deprotonation process for the N-H activation of NH2 pym is suggested. Interestingly, photoluminescence of 1 is switched on at the low temperature of 77 K. PMID:24227790

  3. Optimisation of gain matrix with UZAWA algorithm—theory and application to an active panel

    NASA Astrophysics Data System (ADS)

    Arrouf, Mhamed; Charon, Willy; Peyraut, François

    2004-03-01

    This paper deals with the gain matrix optimisation in the framework of adaptive mechanical systems with LQG control. The purpose of this optimisation is to provide to the engineer the theoretical tools enabling him to position actuators as well as possible on a structure. It was carried out using a conventional UZAWA algorithm which was adapted to the active system context.

  4. Specifying the Influence of Family and Peers on Violent Victimization: Extending Routine Activities and Lifestyle Theories

    ERIC Educational Resources Information Center

    Schreck, Christopher J.; Fisher, Bonnie S.

    2004-01-01

    The fact that crime and victimization share similar correlates suggests that family and peer contexts are potentially useful for explaining individual differences in violent victimization. In this research, we used routine activities and lifestyles frameworks to reveal how strong bonds of family attachment can promote more effective guardianship…

  5. Prediction of attendance at fitness center: a comparison between the theory of planned behavior, the social cognitive theory, and the physical activity maintenance theory.

    PubMed

    Jekauc, Darko; Völkle, Manuel; Wagner, Matthias O; Mess, Filip; Reiner, Miriam; Renner, Britta

    2015-01-01

    In the processes of physical activity (PA) maintenance specific predictors are effective, which differ from other stages of PA development. Recently, Physical Activity Maintenance Theory (PAMT) was specifically developed for prediction of PA maintenance. The aim of the present study was to evaluate the predictability of the future behavior by the PAMT and compare it with the Theory of Planned Behavior (TPB) and Social Cognitive Theory (SCT). Participation rate in a fitness center was observed for 101 college students (53 female) aged between 19 and 32 years (M = 23.6; SD = 2.9) over 20 weeks using a magnetic card. In order to predict the pattern of participation TPB, SCT and PAMT were used. A latent class zero-inflated Poisson growth curve analysis identified two participation patterns: regular attenders and intermittent exercisers. SCT showed the highest predictive power followed by PAMT and TPB. Impeding aspects as life stress and barriers were the strongest predictors suggesting that overcoming barriers might be an important aspect for working out on a regular basis. Self-efficacy, perceived behavioral control, and social support could also significantly differentiate between the participation patterns. PMID:25717313

  6. Prediction of attendance at fitness center: a comparison between the theory of planned behavior, the social cognitive theory, and the physical activity maintenance theory

    PubMed Central

    Jekauc, Darko; Völkle, Manuel; Wagner, Matthias O.; Mess, Filip; Reiner, Miriam; Renner, Britta

    2015-01-01

    In the processes of physical activity (PA) maintenance specific predictors are effective, which differ from other stages of PA development. Recently, Physical Activity Maintenance Theory (PAMT) was specifically developed for prediction of PA maintenance. The aim of the present study was to evaluate the predictability of the future behavior by the PAMT and compare it with the Theory of Planned Behavior (TPB) and Social Cognitive Theory (SCT). Participation rate in a fitness center was observed for 101 college students (53 female) aged between 19 and 32 years (M = 23.6; SD = 2.9) over 20 weeks using a magnetic card. In order to predict the pattern of participation TPB, SCT and PAMT were used. A latent class zero-inflated Poisson growth curve analysis identified two participation patterns: regular attenders and intermittent exercisers. SCT showed the highest predictive power followed by PAMT and TPB. Impeding aspects as life stress and barriers were the strongest predictors suggesting that overcoming barriers might be an important aspect for working out on a regular basis. Self-efficacy, perceived behavioral control, and social support could also significantly differentiate between the participation patterns. PMID:25717313

  7. LoFEx — A local framework for calculating excitation energies: Illustrations using RI-CC2 linear response theory

    NASA Astrophysics Data System (ADS)

    Baudin, Pablo; Kristensen, Kasper

    2016-06-01

    We present a local framework for the calculation of coupled cluster excitation energies of large molecules (LoFEx). The method utilizes time-dependent Hartree-Fock information about the transitions of interest through the concept of natural transition orbitals (NTOs). The NTOs are used in combination with localized occupied and virtual Hartree-Fock orbitals to generate a reduced excitation orbital space (XOS) specific to each transition where a standard coupled cluster calculation is carried out. Each XOS is optimized to ensure that the excitation energies are determined to a predefined precision. We apply LoFEx in combination with the RI-CC2 model to calculate the lowest excitation energies of a set of medium-sized organic molecules. The results demonstrate the black-box nature of the LoFEx approach and show that significant computational savings can be gained without affecting the accuracy of CC2 excitation energies.

  8. The Construction of Metal-Organic Framework with Active Backbones by the Utilization of Reticular Chemistry

    NASA Astrophysics Data System (ADS)

    Choi, Eunwoo

    With the principles of reticular chemistry, metal-organic frameworks with ultra-high porosity, chiral-recognition unit as a chiral stationary phase, metalloporhyrins for enhanced hydrogen adsorption and an intrinsic conductivity to form porous conductors, have been prepared. This dissertation presents how the principles of reticular chemistry were utilized to achieve in the preparations of metal-organic frameworks with a large surface area and active backbones. Through the simple isoreticular (having the same framework topology) expansion from MOF-177 composed with 1,3,5-tris(4'-carboxyphenyl-)benzene (BTB3-) as the strut; MOF-200 was prepared with 4,4',4"-(benzene-1,3,5-triyl-tris(benzene-4,1-diy1))tribenzoic acid an extension from BTB3- by a phenylene unit to yield one of the most porous MOFs with a Langmuir surface area of 10,400 m2. and the lowest density of 0.22 cm3.g-1. A successful thermal polymerization reaction at 325 °C inside of the pores of highly porous MOF, MOF-177, was performed and verified the integrity of the MOF structure even after the thermal reaction. 1,4-Diphenylbutadiyne that is known to polymerize upon heating to form a conjugated backbone was impregnated via solution-diffusion into MOF-177 and then subsequently polymerized by heat to form polymer impregnated MOF-177. Characterization was carried out using powder X-ray diffraction and volumetric sorption analyzer. MOF-1020 with a linear quaterphenyl dicarboxylate-based strut was designed to contain a chiral bisbinaphthyl crown-ether moiety for alkyl ammonium resolution was precisely placed into a Zn4O(CO2)6-based cubic MOF structure. Unfortunately, the chiral resolution was not achieved due to the sensitivity and the pore environment of MOF-1020. However, an interesting phenomenon was observed, where the loss of crystallinity occurs upon solvent removal while the crystallites remain shiny and crystalline, but it readily is restored upon re-solvation of the crystallites. This rare

  9. Metacommunity theory as a multispecies, multiscale framework for studying the influence of river network structure on riverine communities and ecosystems

    USGS Publications Warehouse

    Brown, B.L.; Swan, C.M.; Auerbach, D.A.; Campbell, Grant E.H.; Hitt, N.P.; Maloney, K.O.; Patrick, C.

    2011-01-01

    Explaining the mechanisms underlying patterns of species diversity and composition in riverine networks is challenging. Historically, community ecologists have conceived of communities as largely isolated entities and have focused on local environmental factors and interspecific interactions as the major forces determining species composition. However, stream ecologists have long embraced a multiscale approach to studying riverine ecosystems and have studied both local factors and larger-scale regional factors, such as dispersal and disturbance. River networks exhibit a dendritic spatial structure that can constrain aquatic organisms when their dispersal is influenced by or confined to the river network. We contend that the principles of metacommunity theory would help stream ecologists to understand how the complex spatial structure of river networks mediates the relative influences of local and regional control on species composition. From a basic ecological perspective, the concept is attractive because new evidence suggests that the importance of regional processes (dispersal) depends on spatial structure of habitat and on connection to the regional species pool. The role of local factors relative to regional factors will vary with spatial position in a river network. From an applied perspective, the long-standing view in ecology that local community composition is an indicator of habitat quality may not be uniformly applicable across a river network, but the strength of such bioassessment approaches probably will depend on spatial position in the network. The principles of metacommunity theory are broadly applicable across taxa and systems but seem of particular consequence to stream ecology given the unique spatial structure of riverine systems. By explicitly embracing processes at multiple spatial scales, metacommunity theory provides a foundation on which to build a richer understanding of stream communities.

  10. Brief Report: The Theory of Planned Behaviour Applied to Physical Activity in Young People Who Smoke

    ERIC Educational Resources Information Center

    Everson, Emma S.; Daley, Amanda J.; Ussher, Michael

    2007-01-01

    It has been hypothesised that physical activity may be useful as a smoking cessation intervention for young adults. In order to inform such interventions, this study evaluated the theory of planned behaviour (TPB) for understanding physical activity behaviour in young smokers. Regular smokers aged 16-19 years (N=124), self-reported physical…

  11. Dialogue--Missing in Action Competence: A Cultural Historical Activity Theory Approach in a Botswana School

    ERIC Educational Resources Information Center

    Silo, Nthalivi

    2013-01-01

    An in-depth case study on children's participation in environmental management activities in a primary school in Botswana was undertaken, drawing on cultural historical activity theory (CHAT) and the action competence model. This research revealed that due to a lack of dialogue between teachers and children, teachers tended to view children's…

  12. Activity Theory in Information Systems Research and Practice: Theoretical Underpinnings for an Information Systems Development Model

    ERIC Educational Resources Information Center

    Mursu, Anja; Luukkonen, Irmeli; Toivanen, Marika; Korpela, Mikko

    2007-01-01

    Introduction: The purpose of information systems is to facilitate work activities: here we consider how Activity Theory can be applied in information systems development. Method. The requirements for an analytical model for emancipatory, work-oriented information systems research and practice are specified. Previous research work in Activity…

  13. Contradictions between the Virtual and Physical High School Classroom: A Third-Generation Activity Theory Perspective

    ERIC Educational Resources Information Center

    Murphy, Elizabeth; Manzanares, Maria A. Rodriguez

    2008-01-01

    This paper uses a third-generation Activity Theory perspective to gain insight into the contradictions between the activity systems of the physical and virtual high school classroom from the perspective of teachers who had transitioned from one system to the other. Data collection relied on semi-structured interviews conducted with e-teachers as…

  14. Dynamical Theory of Activated Processes in Globular Proteins

    NASA Astrophysics Data System (ADS)

    Northrup, Scott H.; Pear, Michael R.; Lee, Chyuan-Yih; McCammon, J. Andrew; Karplus, Martin

    1982-07-01

    A methos is described for calculating the reaction rate in globular proteins of activated processes such as ligand binding or enzymatic catalysis. The method is based on the determination of the probability that the system is in the transition state and of the magnitude of the reactive flux for transition-state systems. An ``umbrella sampling'' simulation procedure is outlined for evaluating the transition-state probability. The reactive flux is obtained from an approach described previously for calculating the dynamics of transition-state trajectories. An application to the rotational isomerization of an aromatic ring in the bovine pancreatic trypsin inhibitor is presented. The results demonstrate the feasibility of calculating rate constants for reactions in proteins and point to the importance of solvent effects for reactions that occur near the protein surface.

  15. Dynamical theory of activated processes in globular proteins.

    PubMed Central

    Northrup, S H; Pear, M R; Lee, C Y; McCammon, J A; Karplus, M

    1982-01-01

    A method is described for calculating the reaction rate in globular proteins of activated processes such as ligand binding or enzymatic catalysis. The method is based on the determination of the probability that the system is in the transition state and of the magnitude of the reactive flux for transition-state systems. An "umbrella sampling" simulation procedure is outlined for evaluating the transition-state probability. The reactive flux is obtained from an approach described previously for calculating the dynamics of transition-state trajectories. An application to the rotational isomerization of an aromatic ring in the bovine pancreatic trypsin inhibitor is presented. The results demonstrate the feasibility of calculating rate constants for reactions in proteins and point to the importance of solvent effects for reactions that occur near the protein surface. PMID:6955788

  16. Cultural-historical activity theory: Vygotsky's forgotten and suppressed legacy and its implication for mathematics education

    NASA Astrophysics Data System (ADS)

    Roth, Wolff-Michael

    2012-03-01

    Cultural-historical activity theory—with historical roots in dialectical materialism and the social psychology to which it has given rise—has experienced exponential growth in its acceptance by scholars interested in understanding knowing and learning writ large. In education, this theory has constituted something like a well kept secret that is only in the process of gaining larger levels of acceptance. Mathematics educators are only beginning to realise the tremendous advantages that the theory provides over other theories. In this review essay, I articulate the theory as it may relate to the issues that concern mathematics education and educators with a particular focus on the way in which it addresses logical contradictions in existing theories.

  17. THE ROLE OF CROSS-SHOCK POTENTIAL ON PICKUP ION SHOCK ACCELERATION IN THE FRAMEWORK OF FOCUSED TRANSPORT THEORY

    SciTech Connect

    Zuo, Pingbing; Zhang, Ming; Rassoul, Hamid K.

    2013-10-20

    The focused transport theory is appropriate to describe the injection and acceleration of low-energy particles at shocks as an extension of diffusive shock acceleration (DSA). In this investigation, we aim to characterize the role of cross-shock potential (CSP) originated in the charge separation across the shock ramp on pickup ion (PUI) acceleration at various types of shocks with a focused transport model. The simulation results of energy spectrum and spatial density distribution for the cases with and without CSP added in the model are compared. With sufficient acceleration time, the focused transport acceleration finally falls into the DSA regime with the power-law spectral index equal to the solution of the DSA theory. The CSP can affect the shape of the spectrum segment at lower energies, but it does not change the spectral index of the final power-law spectrum at high energies. It is found that the CSP controls the injection efficiency which is the fraction of PUIs reaching the DSA regime. A stronger CSP jump results in a dramatically improved injection efficiency. Our simulation results also show that the injection efficiency of PUIs is mass-dependent, which is lower for species with a higher mass. In addition, the CSP is able to enhance the particle reflection upstream to produce a stronger intensity spike at the shock front. We conclude that the CSP is a non-negligible factor that affects the dynamics of PUIs at shocks.

  18. Discovery, utilisation and analysis of credible threats for 2×2 incomplete information games in the Theory of Moves framework

    NASA Astrophysics Data System (ADS)

    Olsen, Jolie; Sen, Sandip

    2014-04-01

    Steven Brams's [(1994). Theory of moves. Cambridge University Press] Theory of Moves (TOM) is an alternative to traditional game theoretic treatment of real-life interactions, in which players choose strategies based on analysis of future moves and counter-moves that arise if game play commences at a specified start state and either player can choose to move first. In repeated play, players using TOM rationality arrive at nonmyopic equilibria. One advantage of TOM is its ability to model scenarios in which power asymmetries exist between players. In particular, threat power, i.e. the ability of one player to threaten and sustain immediate, globally disadvantageous outcomes to force a desirable result long term, can be utilised to induce Pareto optimal states in games such as Prisoner's Dilemma which result in Pareto-dominated outcomes using traditional methods. Unfortunately, prior work on TOM is limited by an assumption of complete information. This paper presents a mechanism that can be used by a player to utilise threat power when playing a strict, ordinal 2×2 game under incomplete information. We also analyse the benefits of threat power and support in this analysis with empirical evidence.

  19. Extensions of the Semantic/Syntactic Reasoning Framework

    ERIC Educational Resources Information Center

    Dawkins, Paul Christian

    2012-01-01

    Weber and Alcock's (2004, 2009) syntactic/semantic framework provides a useful means of delineating two basic categories of proof-oriented activity. They define their dichotomy using Goldin's (1998) theory of representation systems. In this paper, I intend to clarify the framework by providing criteria for classifying student reasoning into…

  20. Theory, Investigation and Stability of Cathode Electrocatalytic Activity

    SciTech Connect

    Ding, Dong; Liu, Mingfei; Lai, Samson; Blinn, Kevin; Liu, Meilin

    2012-09-30

    The main objective of this project is to systematically characterize the surface composition, morphology, and electro-catalytic properties of catalysts coated on LSCF, aiming to establish the scientific basis for rational design of high-performance cathodes by combining a porous backbone (such as LSCF) with a thin catalyst coating. The understanding gained will help us to optimize the composition and morphology of the catalyst layer and microstructure of the LSCF backbone for better performance. More specifically, the technical objectives include: (1) to characterize the surface composition, morphology, and electro-catalytic properties of catalysts coated on LSCF; (2) to characterize the microscopic details and stability of the LSCF-catalyst (e.g., LSM) interfaces; (3) to establish the scientific basis for rational design of high-performance cathodes by combining a porous backbone (such as LSCF) with a thin catalyst coating; and (4) to demonstrate that the performance and stability of porous LSCF cathodes can be enhanced by the application of a thin-film coating of LSM through a solution infiltration process in small homemade button cells and in commercially available cells of larger dimension. We have successfully developed dense, conformal LSM films with desired structure, composition, morphology, and thickness on the LSCF surfaces by two different infiltration processes: a non-aqueous and a water-based sol-gel process. It is demonstrated that the activity and stability of LSCF cathodes can be improved by the introduction of a thin-film LSM coating through an infiltration process. Surface and interface of the LSM-coated LSCF cathode were systematically characterized using advanced microscopy and spectroscopy techniques. TEM observation suggests that a layer of La and Sr oxide was formed on LSCF surfaces after annealing. With LSM infiltration, in contrast, we no longer observe such La/Sr oxide layer on the LSM-coated LSCF samples after annealing under similar

  1. Osmium(0) nanoclusters stabilized by zeolite framework; highly active catalyst in the aerobic oxidation of alcohols under mild conditions.

    PubMed

    Zahmakiran, Mehmet; Akbayrak, Serdar; Kodaira, Tetsuya; Ozkar, Saim

    2010-08-28

    Osmium(0) nanoclusters stabilized by zeolite-Y framework were reproducibly prepared by a simple two step procedure involving the incorporation of osmium(III) cations into the zeolite matrix by ion-exchange, followed by their reduction within the cavities of zeolite with sodium borohydride in aqueous solution all at room temperature. The composition and morphology of osmium(0) nanoclusters stabilized by zeolite framework, as well as the integrity and crystallinity of the host material were investigated by using ICP-OES, XRD, XPS, SEM, TEM, HRTEM, TEM/EDX, mid-IR, far-IR spectroscopies, and N(2)-adsorption/desorption technique. The results of the multiprong analysis reveal the formation of osmium(0) nanoclusters within the cavities of zeolite-Y without causing alteration in the framework lattice, formation of mesopores, or loss in the crystallinity of the host material. More importantly, far-IR studies showed that after the reduction of Os(3+) cations by sodium borohydride the Na(+) cations reoccupy their authentic cation sites restoring the integrity of zeolite-Y. The catalytic activity of osmium(0) nanoclusters stabilized by zeolite framework was tested in the aerobic oxidation of activated, unactivated and heteroatom containing alcohols to carbonyl compounds and was found to provide high activity and selectivity even under mild conditions (80 degrees C and 1 atm O(2) or air). Moreover, they were found to be stable enough to be isolated and bottled as solid material, which can be reused as active catalyst under the identical conditions of the first run. PMID:20614055

  2. Unpacking Teacher-Researcher Collaboration with Three Theoretical Frameworks: A Case of Expansive Learning Activity?

    ERIC Educational Resources Information Center

    Gade, Sharada

    2015-01-01

    Long association with a mathematics teacher at a Grade 4-6 school in Sweden, is basis for reporting a case of teacher-researcher collaboration. Three theoretical frameworks used to study its development over time are relational knowing, relational agency and cogenerative dialogue. While relational knowing uses narrative perspectives to explore the…

  3. A Conceptual Framework for the Indirect Method of Reporting Net Cash Flow from Operating Activities

    ERIC Educational Resources Information Center

    Wang, Ting J.

    2010-01-01

    This paper describes the fundamental concept of the reconciliation behind the indirect method of the statement of cash flows. A conceptual framework is presented to demonstrate how accrual and cash-basis accounting methods relate to each other and to illustrate the concept of reconciling these two accounting methods. The conceptual framework…

  4. Developing an ethical framework for short-term international dental and medical activities.

    PubMed

    Friedman, Alexandra; Loh, Lawrence; Evert, Jessica

    2014-01-01

    The popularity of volunteering to provide charity health care in third-world countries has increased dramatically in recent years. While there are advantages to both those being helped and to volunteers, there are also ethical issues that need to be addressed. A framework for analyzing the ethical impact of such service is presented which continues 27 principles that should be addressed. PMID:25080664

  5. Density Functional Theory Study of Hydrogen Adsorption in a Ti-Decorated Mg-Based Metal-Organic Framework-74.

    PubMed

    Suksaengrat, Pitphichaya; Amornkitbamrung, Vittaya; Srepusharawoot, Pornjuk; Ahuja, Rajeev

    2016-03-16

    The Ti-binding energy and hydrogen adsorption energy of a Ti-decorated Mg-based metal-organic framework-74 (Mg-MOF-74) were evaluated by using first-principles calculations. Our results revealed that only three Ti adsorption sites were found to be stable. The adsorption site near the metal oxide unit is the most stable. To investigate the hydrogen-adsorption properties of Ti-functionalized Mg-MOF-74, the hydrogen-binding energy was determined. For the most stable Ti adsorption site, we found that the hydrogen adsorption energy ranged from 0.26 to 0.48 eV H2 (-1) . This is within the desirable range for practical hydrogen-storage applications. Moreover, the hydrogen capacity was determined by using ab initio molecular dynamics simulations. Our results revealed that the hydrogen uptake by Ti-decorated Mg-MOF-74 at temperatures of 77, 150, and 298 K and ambient pressure were 1.81, 1.74, and 1.29 H2  wt %, respectively. PMID:26717417

  6. Synthesis, antimicrobial activity and molecular docking of novel tetracyclic scaffolds incorporating a flavonoid framework with medium sized oxygen heterocycles.

    PubMed

    Dongamanti, Ashok; Aamate, Vikas Kumar; Devulapally, Mohan Gandhi; Gundu, Srinivas; Kotni, Meena Kumari; Manga, Vijjulatha; Balasubramanian, Sridhar; Ernala, Prasad

    2015-02-15

    A convenient approach for the synthesis of novel tetracyclic scaffolds incorporating a flavonoid framework with medium sized heterocyclic rings (eight-, nine-, ten- and eleven-membered rings) containing two oxygen atoms from flavonols through alkylation using different dibromoalkanes was described. The synthesized compounds were established based on the spectral data and X-ray crystal structure for 6c. The synthesized compounds were evaluated for their in vitro antimicrobial activity. Docking studies were carried out for most active two compounds 6f and 6i. PMID:25592711

  7. Analysis of the Effect of Water Activity on Ice Formation Using a New Theory of Nucleation

    NASA Technical Reports Server (NTRS)

    Barahona, Donifan

    2013-01-01

    In this work a new theory of nucleation is developed and used to investigate the effect of water activity on the formation of ice within super-cooled droplets. The new theory is based on a novel concept where the interface is assumed to be made of liquid molecules trapped by the solid matrix. Using this concept new expressions are developed for the critical ice germ size and the nucleation work, with explicit dependencies on temperature and water activity. However unlike previous approaches, the new theory does not depend on the interfacial tension between liquid and ice. Comparison against experimental results shows that the new theory is able to reproduce the observed effect of water activity on nucleation rate and freezing temperature. It allows for the first time a theoretical derivation of the constant shift in water activity between melting and nucleation. The new theory offers a consistent thermodynamic view of ice nucleation, simple enough to be applied in atmospheric models of cloud formation.

  8. Hydrolytically Stable Nanoporous Thorium Mixed Phosphite and Pyrophosphate Framework Generated from Redox-Active Ionothermal Reactions.

    PubMed

    Gui, Daxiang; Zheng, Tao; Chen, Lanhua; Wang, Yanlong; Li, Yuxiang; Sheng, Daopeng; Diwu, Juan; Chai, Zhifang; Albrecht-Schmitt, Thomas E; Wang, Shuao

    2016-04-18

    The first thorium framework compound with mixed-valent phosphorus-based (phosphite and pyrophosphate) ligands, [BMMim]2[Th3(PO3)4(H2P2O7)3] (ThP-1), was synthesized by ionothermal reactions concurrent with the partial oxidation of phosphoric acid. The overall structural topology of ThP-1 highly resembles that of MOF-5, containing only one type of three-dimensional channels with a window size of 11.32 Å × 11.32 Å. ThP-1 has a free void volume of 50.8%, making it one of the most porous purely inorganic actinide-based framework materials. More importantly, ThP-1 is highly stable in aqueous solutions over an extremely wide pH range from 1 to 14 and thus may find potential applications in selective ion exchange and catalysis. PMID:27015432

  9. 2005 Mississippi Curriculum Framework: Secondary Welding Theory and Applications. (Program CIP: 48.0508 - Welding Technology/Welder)

    ERIC Educational Resources Information Center

    Cochran, Harry; Lawrence, Kenneth; Wages, Larry; Box, Dale; Johnston, Joe; Switzer, Ronald

    2005-01-01

    Secondary vocational-technical education programs in Mississippi are faced with many challenges resulting from sweeping educational reforms at the national and state levels. Schools and instructors are increasingly being held accountable for providing true learning activities to every student in the classroom. This accountability is measured…

  10. A Computer-Assisted Framework Based on a Cognitivist Learning Theory for Teaching Mathematics in the Early Primary Years

    ERIC Educational Resources Information Center

    Moradmand, Nasrin; Datta, Amitava; Oakley, Grace

    2012-01-01

    With the world moving rapidly into digital media and information, the ways in which learning activities in mathematics can be created and delivered are changing. However, to get the best results from the integration of ICTs in education, any application's design and development needs to be based on pedagogically appropriate principles, in terms of…

  11. Bank robberies by an Asian gang: an assessment of the routine activities theory.

    PubMed

    Wang, John Z

    2002-10-01

    It was reported for the first time that a series of bank robberies were committed by an Asian gang group in a major southern city. The bank robberies showed a variety of operational methods. The purpose of this descriptive study is to apply the routine activities theory to explain the causal factors of the robberies. The analysis shows that the six Asian bank robberies resulted from a supply of motivated offenders, the availability of suitable targets, and a low level of capable guardians against crime. Findings suggest that crime-specific measures are an appropriate method for examining the merits of the routine activities theory. PMID:12365143

  12. Density functional theory based calculations of the transfer integral in a redox-active single-molecule junction

    NASA Astrophysics Data System (ADS)

    Kastlunger, Georg; Stadler, Robert

    2014-03-01

    There are various quantum chemical approaches for an ab initio description of transfer integrals within the framework of Marcus theory in the context of electron transfer reactions. In our paper, we aim to calculate transfer integrals in redox-active single molecule junctions, where we focus on the coherent tunneling limit with the metal leads taking the position of donor and acceptor and the molecule acting as a transport mediating bridge. This setup allows us to derive a conductance, which can be directly compared with recent results from a nonequilibrium Green's function approach. Compared with purely molecular systems we face additional challenges due to the metallic nature of the leads, which rules out some of the common techniques, and due to their periodicity, which requires k-space integration. We present three different methods, all based on density functional theory, for calculating the transfer integral under these constraints, which we benchmark on molecular test systems from the relevant literature. We also discuss many-body effects and apply all three techniques to a junction with a Ruthenium complex in different oxidation states.

  13. Spin-orbit couplings within the equation-of-motion coupled-cluster framework: Theory, implementation, and benchmark calculations

    NASA Astrophysics Data System (ADS)

    Epifanovsky, Evgeny; Klein, Kerstin; Stopkowicz, Stella; Gauss, Jürgen; Krylov, Anna I.

    2015-08-01

    We present a formalism and an implementation for calculating spin-orbit couplings (SOCs) within the EOM-CCSD (equation-of-motion coupled-cluster with single and double substitutions) approach. The following variants of EOM-CCSD are considered: EOM-CCSD for excitation energies (EOM-EE-CCSD), EOM-CCSD with spin-flip (EOM-SF-CCSD), EOM-CCSD for ionization potentials (EOM-IP-CCSD) and electron attachment (EOM-EA-CCSD). We employ a perturbative approach in which the SOCs are computed as matrix elements of the respective part of the Breit-Pauli Hamiltonian using zeroth-order non-relativistic wave functions. We follow the expectation-value approach rather than the response-theory formulation for property calculations. Both the full two-electron treatment and the mean-field approximation (a partial account of the two-electron contributions) have been implemented and benchmarked using several small molecules containing elements up to the fourth row of the periodic table. The benchmark results show the excellent performance of the perturbative treatment and the mean-field approximation. When used with an appropriate basis set, the errors with respect to experiment are below 5% for the considered examples. The findings regarding basis-set requirements are in agreement with previous studies. The impact of different correlation treatment in zeroth-order wave functions is analyzed. Overall, the EOM-IP-CCSD, EOM-EA-CCSD, EOM-EE-CCSD, and EOM-SF-CCSD wave functions yield SOCs that agree well with each other (and with the experimental values when available). Using an EOM-CCSD approach that provides a more balanced description of the target states yields more accurate results.

  14. Cognitive decision errors and organization vulnerabilities in nuclear power plant safety management: Modeling using the TOGA meta-theory framework

    SciTech Connect

    Cappelli, M.; Gadomski, A. M.; Sepiellis, M.; Wronikowska, M. W.

    2012-07-01

    In the field of nuclear power plant (NPP) safety modeling, the perception of the role of socio-cognitive engineering (SCE) is continuously increasing. Today, the focus is especially on the identification of human and organization decisional errors caused by operators and managers under high-risk conditions, as evident by analyzing reports on nuclear incidents occurred in the past. At present, the engineering and social safety requirements need to enlarge their domain of interest in such a way to include all possible losses generating events that could be the consequences of an abnormal state of a NPP. Socio-cognitive modeling of Integrated Nuclear Safety Management (INSM) using the TOGA meta-theory has been discussed during the ICCAP 2011 Conference. In this paper, more detailed aspects of the cognitive decision-making and its possible human errors and organizational vulnerability are presented. The formal TOGA-based network model for cognitive decision-making enables to indicate and analyze nodes and arcs in which plant operators and managers errors may appear. The TOGA's multi-level IPK (Information, Preferences, Knowledge) model of abstract intelligent agents (AIAs) is applied. In the NPP context, super-safety approach is also discussed, by taking under consideration unexpected events and managing them from a systemic perspective. As the nature of human errors depends on the specific properties of the decision-maker and the decisional context of operation, a classification of decision-making using IPK is suggested. Several types of initial situations of decision-making useful for the diagnosis of NPP operators and managers errors are considered. The developed models can be used as a basis for applications to NPP educational or engineering simulators to be used for training the NPP executive staff. (authors)

  15. Electron dynamics in complex environments with real-time time dependent density functional theory in a QM-MM framework

    SciTech Connect

    Morzan, Uriel N.; Ramírez, Francisco F.; Scherlis, Damián A. E-mail: mcgl@qb.ffyb.uba.ar; Lebrero, Mariano C. González E-mail: mcgl@qb.ffyb.uba.ar

    2014-04-28

    This article presents a time dependent density functional theory (TDDFT) implementation to propagate the Kohn-Sham equations in real time, including the effects of a molecular environment through a Quantum-Mechanics Molecular-Mechanics (QM-MM) hamiltonian. The code delivers an all-electron description employing Gaussian basis functions, and incorporates the Amber force-field in the QM-MM treatment. The most expensive parts of the computation, comprising the commutators between the hamiltonian and the density matrix—required to propagate the electron dynamics—, and the evaluation of the exchange-correlation energy, were migrated to the CUDA platform to run on graphics processing units, which remarkably accelerates the performance of the code. The method was validated by reproducing linear-response TDDFT results for the absorption spectra of several molecular species. Two different schemes were tested to propagate the quantum dynamics: (i) a leap-frog Verlet algorithm, and (ii) the Magnus expansion to first-order. These two approaches were confronted, to find that the Magnus scheme is more efficient by a factor of six in small molecules. Interestingly, the presence of iron was found to seriously limitate the length of the integration time step, due to the high frequencies associated with the core-electrons. This highlights the importance of pseudopotentials to alleviate the cost of the propagation of the inner states when heavy nuclei are present. Finally, the methodology was applied to investigate the shifts induced by the chemical environment on the most intense UV absorption bands of two model systems of general relevance: the formamide molecule in water solution, and the carboxy-heme group in Flavohemoglobin. In both cases, shifts of several nanometers are observed, consistently with the available experimental data.

  16. Electron dynamics in complex environments with real-time time dependent density functional theory in a QM-MM framework

    NASA Astrophysics Data System (ADS)

    Morzan, Uriel N.; Ramírez, Francisco F.; Oviedo, M. Belén; Sánchez, Cristián G.; Scherlis, Damián A.; Lebrero, Mariano C. González

    2014-04-01

    This article presents a time dependent density functional theory (TDDFT) implementation to propagate the Kohn-Sham equations in real time, including the effects of a molecular environment through a Quantum-Mechanics Molecular-Mechanics (QM-MM) hamiltonian. The code delivers an all-electron description employing Gaussian basis functions, and incorporates the Amber force-field in the QM-MM treatment. The most expensive parts of the computation, comprising the commutators between the hamiltonian and the density matrix—required to propagate the electron dynamics—, and the evaluation of the exchange-correlation energy, were migrated to the CUDA platform to run on graphics processing units, which remarkably accelerates the performance of the code. The method was validated by reproducing linear-response TDDFT results for the absorption spectra of several molecular species. Two different schemes were tested to propagate the quantum dynamics: (i) a leap-frog Verlet algorithm, and (ii) the Magnus expansion to first-order. These two approaches were confronted, to find that the Magnus scheme is more efficient by a factor of six in small molecules. Interestingly, the presence of iron was found to seriously limitate the length of the integration time step, due to the high frequencies associated with the core-electrons. This highlights the importance of pseudopotentials to alleviate the cost of the propagation of the inner states when heavy nuclei are present. Finally, the methodology was applied to investigate the shifts induced by the chemical environment on the most intense UV absorption bands of two model systems of general relevance: the formamide molecule in water solution, and the carboxy-heme group in Flavohemoglobin. In both cases, shifts of several nanometers are observed, consistently with the available experimental data.

  17. Spin-orbit couplings within the equation-of-motion coupled-cluster framework: Theory, implementation, and benchmark calculations.

    PubMed

    Epifanovsky, Evgeny; Klein, Kerstin; Stopkowicz, Stella; Gauss, Jürgen; Krylov, Anna I

    2015-08-14

    We present a formalism and an implementation for calculating spin-orbit couplings (SOCs) within the EOM-CCSD (equation-of-motion coupled-cluster with single and double substitutions) approach. The following variants of EOM-CCSD are considered: EOM-CCSD for excitation energies (EOM-EE-CCSD), EOM-CCSD with spin-flip (EOM-SF-CCSD), EOM-CCSD for ionization potentials (EOM-IP-CCSD) and electron attachment (EOM-EA-CCSD). We employ a perturbative approach in which the SOCs are computed as matrix elements of the respective part of the Breit-Pauli Hamiltonian using zeroth-order non-relativistic wave functions. We follow the expectation-value approach rather than the response-theory formulation for property calculations. Both the full two-electron treatment and the mean-field approximation (a partial account of the two-electron contributions) have been implemented and benchmarked using several small molecules containing elements up to the fourth row of the periodic table. The benchmark results show the excellent performance of the perturbative treatment and the mean-field approximation. When used with an appropriate basis set, the errors with respect to experiment are below 5% for the considered examples. The findings regarding basis-set requirements are in agreement with previous studies. The impact of different correlation treatment in zeroth-order wave functions is analyzed. Overall, the EOM-IP-CCSD, EOM-EA-CCSD, EOM-EE-CCSD, and EOM-SF-CCSD wave functions yield SOCs that agree well with each other (and with the experimental values when available). Using an EOM-CCSD approach that provides a more balanced description of the target states yields more accurate results. PMID:26277122

  18. Spin-orbit couplings within the equation-of-motion coupled-cluster framework: Theory, implementation, and benchmark calculations

    SciTech Connect

    Epifanovsky, Evgeny; Klein, Kerstin; Gauss, Jürgen; Stopkowicz, Stella; Krylov, Anna I.

    2015-08-14

    We present a formalism and an implementation for calculating spin-orbit couplings (SOCs) within the EOM-CCSD (equation-of-motion coupled-cluster with single and double substitutions) approach. The following variants of EOM-CCSD are considered: EOM-CCSD for excitation energies (EOM-EE-CCSD), EOM-CCSD with spin-flip (EOM-SF-CCSD), EOM-CCSD for ionization potentials (EOM-IP-CCSD) and electron attachment (EOM-EA-CCSD). We employ a perturbative approach in which the SOCs are computed as matrix elements of the respective part of the Breit-Pauli Hamiltonian using zeroth-order non-relativistic wave functions. We follow the expectation-value approach rather than the response-theory formulation for property calculations. Both the full two-electron treatment and the mean-field approximation (a partial account of the two-electron contributions) have been implemented and benchmarked using several small molecules containing elements up to the fourth row of the periodic table. The benchmark results show the excellent performance of the perturbative treatment and the mean-field approximation. When used with an appropriate basis set, the errors with respect to experiment are below 5% for the considered examples. The findings regarding basis-set requirements are in agreement with previous studies. The impact of different correlation treatment in zeroth-order wave functions is analyzed. Overall, the EOM-IP-CCSD, EOM-EA-CCSD, EOM-EE-CCSD, and EOM-SF-CCSD wave functions yield SOCs that agree well with each other (and with the experimental values when available). Using an EOM-CCSD approach that provides a more balanced description of the target states yields more accurate results.

  19. Theory-Based Interventions in Physical Activity: A Systematic Review of Literature in Iran

    PubMed Central

    Abdi, Jalal; Eftekhar, Hassan; Estebsari, Fatemeh; Sadeghi, Roya

    2015-01-01

    Lack of physical activity is ranked fourth among the causes of human death and chronic diseases. Using models and theories to design, implement, and evaluate the health education and health promotion interventions has many advantages. Using models and theories of physical activity, we decided to systematically study the educational and promotional interventions carried out in Iran from 2003 to 2013.Three information databases were used to systematically select papers using key words including Iranian Magazine Database (MAGIRAN), Iran Medical Library (MEDLIB), and Scientific Information Database (SID). Twenty papers were selected and studied. Having been applied in 9 studies, The Trans Theoretical Model (TTM) was the most widespread model in Iran (PENDER in 3 studies, BASNEF in 2, and the Theory of Planned Behavior in 2 studies). With regards to the educational methods, almost all studies used a combination of methods. The most widely used Integrative educational method was group discussion. Only one integrated study was done. Behavior maintenance was not addressed in 75% of the studies. Almost all studies used self-reporting instruments. The effectiveness of educational methods was assessed in none of the studies. Most of the included studies had several methodological weaknesses, which hinder the validity and applicability of their results. According to the findings, the necessity of need assessment in using models, epidemiology and methodology consultation, addressing maintenance of physical activity, using other theories and models such as social marketing and social-cognitive theory, and other educational methods like empirical and complementary are suggested. PMID:25948454

  20. Theory-based interventions in physical activity: a systematic review of literature in Iran.

    PubMed

    Abdi, Jalal; Eftekhar, Hassan; Estebsari, Fatemeh; Sadeghi, Roya

    2015-01-01

    Lack of physical activity is ranked fourth among the causes of human death and chronic diseases. Using models and theories to design, implement, and evaluate the health education and health promotion interventions has many advantages. Using models and theories of physical activity, we decided to systematically study the educational and promotional interventions carried out in Iran from 2003 to 2013.Three information databases were used to systematically select papers using key words including Iranian Magazine Database (MAGIRAN), Iran Medical Library (MEDLIB), and Scientific Information Database (SID). Twenty papers were selected and studied .Having been applied in 9 studies, The Trans Theoretical Model (TTM) was the most widespread model in Iran (PENDER in 3 studies, BASNEF in 2, and the Theory of Planned Behavior in 2 studies). With regards to the educational methods, almost all studies used a combination of methods. The most widely used Integrative educational method was group discussion. Only one integrated study was done. Behavior maintenance was not addressed in 75% of the studies. Almost all studies used self-reporting instruments. The effectiveness of educational methods was assessed in none of the studies. Most of the included studies had several methodological weaknesses, which hinder the validity and applicability of their results. According to the findings, the necessity of need assessment in using models, epidemiology and methodology consultation, addressing maintenance of physical activity, using other theories and models such as social marketing and social-cognitive theory, and other educational methods like empirical and complementary are suggested. PMID:25948454

  1. Ultrastable Polymolybdate-Based Metal-Organic Frameworks as Highly Active Electrocatalysts for Hydrogen Generation from Water.

    PubMed

    Qin, Jun-Sheng; Du, Dong-Ying; Guan, Wei; Bo, Xiang-Jie; Li, Ya-Fei; Guo, Li-Ping; Su, Zhong-Min; Wang, Yuan-Yuan; Lan, Ya-Qian; Zhou, Hong-Cai

    2015-06-10

    Two novel polyoxometalate (POM)-based metal-organic frameworks (MOFs), [TBA]3[ε-PMo(V)8Mo(VI)4O36(OH)4Zn4][BTB]4/3·xGuest (NENU-500, BTB = benzene tribenzoate, TBA(+) = tetrabutylammonium ion) and [TBA]3[ε-PMo(V)8Mo(VI)4O37(OH)3Zn4][BPT] (NENU-501, BPT = [1,1'-biphenyl]-3,4',5-tricarboxylate), were isolated. In these compounds, the POM fragments serving as nodes were directly connected with organic ligands giving rise to three-dimensional (3D) open frameworks. The two anionic frameworks were balanced by TBA(+) ions residing inside the open channels. They exhibit not only good stability in air but also tolerance to acidic and basic media. Furthermore, they were employed as electrocatalysts for the hydrogen evolution reaction (HER) owing to the combination of the redox activity of a POM unit and the porosity of a MOF. Meanwhile, the HER activities of ε(trim)(4/3), NENU-5, and HKUST-1 were also studied for comparison. Remarkably, as a 3D hydrogen-evolving cathode operating in acidic electrolytes, NENU-500 exhibits the highest activity among all MOF materials. It shows an onset overpotential of 180 mV and a Tafel slope of 96 mV·dec(-1), and the catalytic current density can approach 10 mA·cm(-2) at an overpotential of 237 mV. Moreover, NENU-500 and NENU-501 maintain their electrocatalytic activities after 2000 cycles. PMID:25933041

  2. Chapter 2: Theoretical Models for Understanding Physical Activity Behavior among Children and Adolescents--Social Cognitive Theory and Self-Determination Theory

    ERIC Educational Resources Information Center

    Motl, Robert W.

    2007-01-01

    The study of physical activity behavior in youth generally lacks a sufficient theoretical foundation for examining variables that influence that behavior. This is a major limitation because theory guides the search for determinants of behavior and the subsequent interplay between research findings and application. Theory offers a systematically…

  3. Applying the Theory of Planned Behavior to Physical Activity: The Moderating Role of Mental Toughness.

    PubMed

    Hannan, Thomas E; Moffitt, Robyn L; Neumann, David L; Thomas, Patrick R

    2015-10-01

    This study explored whether mental toughness, the capacity to maintain performance under pressure, moderated the relation between physical activity intentions and subsequent behavior. Participants (N = 117) completed the Mental Toughness Index and a theory of planned behavior questionnaire. Seven days later, physical activity was assessed using the International Physical Activity Questionnaire. Attitudes, subjective norms, and perceived behavioral control explained substantial variance (63.1%) in physical activity intentions. Intentions also significantly predicted physical activity behavior. The simple slopes analyses for the moderation effect revealed a nonsignificant intention-behavior relation at low levels of mental toughness. However, intentions were significantly and positively related to physical activity when mental toughness was moderate or high, suggesting that the development of a mentally tough mindset may reduce the gap between behavior and physical activity intention. Future research is needed to confirm these findings and apply them in the design of mental toughness interventions to facilitate physical activity engagement. PMID:26524097

  4. Second-Order Perturbation Theory for Generalized Active Space Self-Consistent-Field Wave Functions.

    PubMed

    Ma, Dongxia; Li Manni, Giovanni; Olsen, Jeppe; Gagliardi, Laura

    2016-07-12

    A multireference second-order perturbation theory approach based on the generalized active space self-consistent-field (GASSCF) wave function is presented. Compared with the complete active space (CAS) and restricted active space (RAS) wave functions, GAS wave functions are more flexible and can employ larger active spaces and/or different truncations of the configuration interaction expansion. With GASSCF, one can explore chemical systems that are not affordable with either CASSCF or RASSCF. Perturbation theory to second order on top of GAS wave functions (GASPT2) has been implemented to recover the remaining electron correlation. The method has been benchmarked by computing the chromium dimer ground-state potential energy curve. These calculations show that GASPT2 gives results similar to CASPT2 even with a configuration interaction expansion much smaller than the corresponding CAS expansion. PMID:27276688

  5. A Critical Analysis of Active Learning and an Alternative Pedagogical Framework for Introductory Information Systems Courses

    ERIC Educational Resources Information Center

    Drake, John R.

    2012-01-01

    Active learning has been championed in academic circles as the pedagogical fix to boring lectures typically found in introduction to information systems courses. However, the literature on active learning is mixed. In this paper, we critically examine active learning research and discover a misplaced emphasis leading to paradoxical findings in…

  6. A new 3-D open-framework cadmium borovanadate with plane-shaped channels and high catalytic activity for the oxidation of cyclohexanol.

    PubMed

    Feng, Yuquan; Qiu, Dongfang; Fan, Huitao; Li, Min; Huang, Qunzeng; Shi, Hengzhen

    2015-05-21

    A new 3-D open-framework cadmium borovanadate with 6-connected topology was hydrothermally obtained and structurally characterized. It not only features new cadmium(II) borovanadate which possesses an open-framework structure with unique plane-shaped channels, but also exhibits interesting absorption properties and high catalytic activities for the oxidation of cyclohexanol. PMID:25882921

  7. Using Telephone Conversations to Develop Awareness of Pragmatic Skills: An Activity-Theory-Driven Approach

    ERIC Educational Resources Information Center

    Xia, Saihua

    2009-01-01

    This paper investigates ESL learners' awareness of pragmatic skills utilizing an activity-theory driven approach to perform an inquiry task into problem-solving service call conversations (PSSCs) between native speakers (NS) and non-native speakers of English (NNSs). Eight high-intermediate ESL learners, from five different language backgrounds,…

  8. An Activity Theory Exegesis on Conflict and Contradictions in Networked Discussions and Feedback Exchanges

    ERIC Educational Resources Information Center

    Hadjistassou, Stella K.

    2012-01-01

    The goal of this study was to investigate the culturally afforded contradictions that ten advanced English as a Second Language (ESL) learner encountered when they posted their paper topics and exchanged feedback strategies online and contextualized some of these strategies to draft their papers. Using Cultural-Historical Activity Theory (CHAT),…

  9. Preparing Students for Education, Work, and Community: Activity Theory in Task-Based Curriculum Design

    ERIC Educational Resources Information Center

    Campbell, Chris; MacPherson, Seonaigh; Sawkins, Tanis

    2014-01-01

    This case study describes how sociocultural and activity theory were applied in the design of a publicly funded, Canadian Language Benchmark (CLB)-based English as a Second Language (ESL) credential program and curriculum for immigrant and international students in postsecondary institutions in British Columbia, Canada. The ESL Pathways Project…

  10. Rules, Roles and Tools: Activity Theory and the Comparative Study of E-Learning

    ERIC Educational Resources Information Center

    Benson, Angela; Lawler, Cormac; Whitworth, Andrew

    2008-01-01

    Activity theory (AT) is a powerful tool for investigating "artefacts in use", ie, the ways technologies interrelate with their local context. AT reveals the interfaces between e-learning at the macro- (strategy, policy, "campus-wide" solutions) and the micro-organisational levels (everyday working practice, iterative change, individual…

  11. Investigating Acceptance toward Mobile Learning to Assist Individual Knowledge Management: Based on Activity Theory Approach

    ERIC Educational Resources Information Center

    Liaw, Shu-Sheng; Hatala, Marek; Huang, Hsiu-Mei

    2010-01-01

    Mobile devices could facilitate human interaction and access to knowledge resources anytime and anywhere. With respect to wide application possibilities of mobile learning, investigating learners' acceptance towards it is an essential issue. Based on activity theory approach, this research explores positive factors for the acceptance of m-learning…

  12. Generalization of the Activated Complex Theory of Reaction Rates. II. Classical Mechanical Treatment

    DOE R&D Accomplishments Database

    Marcus, R. A.

    1964-01-01

    In its usual classical form activated complex theory assumes a particular expression for the kinetic energy of the reacting system -- one associated with a rectilinear motion along the reaction coordinate. The derivation of the rate expression given in the present paper is based on the general kinetic energy expression.

  13. Ethical Issues in Agency Evaluation from the Viewpoint of Activity Theory: A Basis for Interorganizational Learning?

    ERIC Educational Resources Information Center

    Huotari, Risto

    2009-01-01

    This article focuses on ethical issues faced in evaluation practice from the viewpoint of third generation of activity theory, which gives a constructive perspective on how contradictions can be a driving force behind interorganizational learning and development in multiactor networks. The problem field is firstly addressed through an illustration…

  14. Exploring Physical Activity by Ethnicity and Gender in College Students Using Social Cognitive Theory

    ERIC Educational Resources Information Center

    Nehl, Eric J.; Blanchard, Chris M.; Kupperman, Janet; Sparling, Phillip; Rhodes, Ryan; Torabi, Mohammad R.; Courneya, Kerry S.

    2012-01-01

    Intervention;The psychological determinants of physical activity (PA) among college students may vary by ethnicity and gender, but few studies have considered these characteristics. This study tested constructs from Social Cognitive Theory (SCT) by ethnicity and gender to explain differences in PA. A total of 231 Blacks (70% female) and 218 White…

  15. Language-Learning Motivation during Short-Term Study Abroad: An Activity Theory Perspective

    ERIC Educational Resources Information Center

    Allen, Heather Willis

    2010-01-01

    This study investigated the development of language-learning motivation during short-term study abroad (SA) for six intermediate-level students of French. Taking an activity theory perspective, findings demonstrated that one of two orientations motivated participants to study or continue studying French at the college level: linguistic motives or…

  16. The Transformation of Learning: Advances in Cultural-Historical Activity Theory

    ERIC Educational Resources Information Center

    van Oers, Bert, Ed.; Wardekker, Wim, Ed.; Elbers, Ed, Ed.; van der Veer, Rene, Ed.

    2010-01-01

    Learning is a changing phenomenon, depending on the advances in theory and research. This book presents a relatively new approach to learning, based on meaningful human activities in cultural practices and in collaboration with others. It draws extensively from the ideas of Lev Vygotsky and his recent followers. The book presents ideas that…

  17. Self-Identity as a Component of the Theory of Planned Behaviour in Predicting Physical Activity

    ERIC Educational Resources Information Center

    Ries, Francis; Hein, Vello; Pihu, Maret; Armenta, Jose Manuel Sevillano

    2012-01-01

    This study aimed to investigate the role of self-identity, defined as salient and enduring aspects of one's self-perception (Sparks, 2000), in relation to adolescent physical activity (PA) intentions within the Theory of Planned Behaviour (TPB). School students aged 12 to 18 from two cultural groups (Estonia and Spain) completed measures of…

  18. Using Activity Theory and its Principle of Contradictions to Guide Research in Educational Technology

    ERIC Educational Resources Information Center

    Murphy, Elizabeth; Rodriguez-Manzanares, Maria A.

    2008-01-01

    This paper describes how activity theory (AT) and its principle of contradictions may be relied on to guide research in educational technology. The paper begins with a theoretical overview of AT and of its principle of contradictions. It follows with a synthesis of studies that have used AT as a lens to study information and communication…

  19. Ethnicity as a Moderator of the Theory of Planned Behavior and Physical Activity in College Students

    ERIC Educational Resources Information Center

    Blanchard, Chris M.; Kupperman, Janet; Sparling, Phil; Nehl, Eric; Rhodes, Ryan E.; Courneya, Kerry S.; Baker, Frank; Hunt, Tiffany

    2007-01-01

    Most college students do not meet physical activity (PA) guidelines, and ethnic disparities exist. The present study examined the utility of the theory of planned behavior (TPB) in explaining PA intentions and behavior in black and white college students and whether any TPB relationships were moderated by ethnicity. Black (n = 170) and white (n =…

  20. Activity Theory and Technology Mediated Interaction: Cognitive Scaffolding Using Question-Based Consultation on "Facebook"

    ERIC Educational Resources Information Center

    Rambe, Patient

    2012-01-01

    Studies that employed activity theory as a theoretical lens for exploring computer-mediated interaction have not adopted social media as their object of study. However, social media provides lecturers with personalised learning environments for diagnostic and prognostic assessments of student mastery of content and deep learning. The integration…

  1. An Activity Theory Perspective on Student-Reported Contradictions in International Telecollaboration

    ERIC Educational Resources Information Center

    Basharina, Olga K.

    2007-01-01

    This process-oriented study focuses on contradictions that emerged in a WebCT bulletin board collaboration among English learners from Japan, Mexico and Russia, and explains them from the perspective of activity theory (Leont'ev, 1978, 1981; Engestrom, 1987, 1999). The study identified a) two "intra-cultural" contradictions--to post or not to…

  2. Investigating Learner Attitudes toward E-Books as Learning Tools: Based on the Activity Theory Approach

    ERIC Educational Resources Information Center

    Liaw, Shu-Sheng; Huang, Hsiu-Mei

    2016-01-01

    This paper investigates the use of e-books as learning tools in terms of learner satisfaction, usefulness, behavioral intention, and learning effectiveness. Based on the activity theory approach, this research develops a research model to understand learner attitudes toward e-books in two physical sizes: 10? and 7?. Results suggest that screen…

  3. Discourse of the Firetenders: Considering Contingent Faculty through the Lens of Activity Theory

    ERIC Educational Resources Information Center

    Doe, Sue; Barnes, Natalie; Bowen, David; Gilkey, David; Smoak, Ginger Guardiola; Ryan, Sarah; Sarell, Kirk; Thomas, Laura H.; Troup, Lucy J.; Palmquist, Mike

    2011-01-01

    In this article, the authors explore the multiple roles that contingent faculty play in an evolving system of higher education. They consider the professional work of faculty in contingent positions at Colorado State University through the lens of activity theory, analyzing workplace discourse logs in an effort to understand the roles of…

  4. Experiences of Learning and Teaching Mathematics: Using Activity Theory to Understand Tensions in Practice

    ERIC Educational Resources Information Center

    Page, Shaileigh; Clark, Julie

    2010-01-01

    This paper originates from a larger qualitative study exploring how teachers incorporate the affective domain into the primary mathematics classroom. This paper analyses teacher's experiences of mathematics and explores, using activity theory, how these experiences impact their teaching. An important factor to emerge from the data was teacher's…

  5. Understanding and Dismantling Barriers for Partnerships for Inclusive Education: A Cultural Historical Activity Theory Perspective

    ERIC Educational Resources Information Center

    Waitoller, Federico R.; Kozleski, Elizabeth B.

    2013-01-01

    Increasingly, universities and school districts share responsibility for teacher and student learning. Sharing responsibility demands that both institutions work to develop closer relationships through ongoing engagement, dialogue and negotiation. Drawing from Cultural Historical Activity Theory (CHAT), we examined one school/university…

  6. Using Social Cognitive Theory to Predict Physical Activity and Fitness in Underserved Middle School Children

    ERIC Educational Resources Information Center

    Martin, Jeffrey J.; McCaughtry, Nate; Flory, Sara; Murphy, Anne; Wisdom, Kimberlydawn

    2011-01-01

    Few researchers have used social cognitive theory and environment-based constructs to predict physical activity (PA) and fitness in underserved middle-school children. Hence, we evaluated social cognitive variables and perceptions of the school environment to predict PA and fitness in middle school children (N = 506, ages 10-14 years). Using…

  7. Modernity, the Individual, and the Foundations of Cultural-Historical Activity Theory

    ERIC Educational Resources Information Center

    Blunden, Andy

    2007-01-01

    It is argued that the problem of individual agency in relation to social institutions can be resolved within Cultural-Historical Activity Theory (CHAT) by the use of the "subject" as a unit of analysis. Such an approach implies a reaffirmation of the fundamental tenets of CHAT but also a critique of the concepts of society and culture, which are…

  8. Science and Social Practice: Action Research and Activity Theory as Socio-Critical Approaches

    ERIC Educational Resources Information Center

    Langemeyer, Ines

    2011-01-01

    Action research and activity theory are considered by a number of followers as socio-critical approaches, whereas others do not relate them to social-criticism and use them merely as methods to improve practice. This article searches for general insights in Kurt Lewin's and Lev S. Vygotsky's work into how one proceeds and acts critically. In their…

  9. Activity Theory, Complexity and Sports Coaching: An Epistemology for a Discipline

    ERIC Educational Resources Information Center

    Jones, Robyn L.; Edwards, Christian; Filho, I. A. Tuim Viotto

    2016-01-01

    The aim of this article is twofold. First, it is to advance the case for activity theory (AT) as a credible and alternative lens to view and research sports coaching. Second, it is to position this assertion within the wider debate about the epistemology of coaching. Following a framing introduction, a more comprehensive review of the development…

  10. Generalization of the Activated Complex Theory of Reaction Rates. I. Quantum Mechanical Treatment

    DOE R&D Accomplishments Database

    Marcus, R. A.

    1964-01-01

    In its usual form activated complex theory assumes a quasi-equilibrium between reactants and activated complex, a separable reaction coordinate, a Cartesian reaction coordinate, and an absence of interaction of rotation with internal motion in the complex. In the present paper a rate expression is derived without introducing the Cartesian assumption. The expression bears a formal resemblance to the usual one and reduces to it when the added assumptions of the latter are introduced.

  11. An empirical test of the decision to lie component of the Activation-Decision-Construction-Action Theory (ADCAT).

    PubMed

    Masip, Jaume; Blandón-Gitlin, Iris; de la Riva, Clara; Herrero, Carmen

    2016-09-01

    Meta-analyses reveal that behavioral differences between liars and truth tellers are small. To facilitate lie detection, researchers are currently developing interviewing approaches to increase these differences. Some of these approaches assume that lying is cognitively more difficult than truth telling; however, they are not based on specific cognitive theories of lie production, which are rare. Here we examined one existing theory, Walczyk et al.'s (2014) Activation-Decision-Construction-Action Theory (ADCAT). We tested the Decision component. According to ADCAT, people decide whether to lie or tell the truth as if they were using a specific mathematical formula to calculate the motivation to lie from (a) the probability of a number of outcomes derived from lying vs. telling the truth, and (b) the costs/benefits associated with each outcome. In this study, participants read several hypothetical scenarios and indicated whether they would lie or tell the truth in each scenario (Questionnaire 1). Next, they answered several questions about the consequences of lying vs. telling the truth in each scenario, and rated the probability and valence of each consequence (Questionnaire 2). Significant associations were found between the participants' dichotomous decision to lie/tell the truth in Questionnaire 1 and their motivation to lie scores calculated from the Questionnaire 2 data. However, interestingly, whereas the expected consequences of truth telling were associated with the decision to lie vs. tell the truth, the expected consequences of lying were not. Suggestions are made to refine ADCAT, which can be a useful theoretical framework to guide deception research. PMID:27219533

  12. Shrink wrapping redox-active crystals of polyoxometalate open frameworks with organic polymers via crystal induced polymerisation.

    PubMed

    Takashima, Yohei; Miras, Haralampos N; Glatzel, Stefan; Cronin, Leroy

    2016-06-14

    We report examples of crystal surface modification of polyoxometalate open frameworks whereby the use of pyrrole or aniline as monomers leads to the formation of the corresponding polymers via an oxidative polymerization process initiated by the redox active POM scaffolds. Guest-exchange experiments demonstrate that the polymers can finely tune the guest exchange rate and their structural integrity is retained after the surface modifications. In addition, the formation of polyoxometalate-based self-fabricating tubes by the dissolution of Keggin-based network crystals were also modulated by the polymers, allowing a new type of hybrid inorganic polymer with an organic coating to be fabricated. PMID:27203804

  13. Copper metal-organic framework nanocrystal for plane effect nonenzymatic electro-catalytic activity of glucose.

    PubMed

    Liu, Yuanying; Zhang, Youjuan; Chen, Jing; Pang, Huan

    2014-10-01

    This work describes the first demonstration of nanocrystal plane dependent nonenzymatic electro-catalytic glucose activity of [Cu3(btc)2] nanocrystals with different shapes (nanocube, truncated cube, cuboctahedron, and octahedron). From electrochemical results, the obtained [Cu3(btc)2] nanocube modified electrode shows the best nonenzymatic electro-catalytic glucose activity. Interestingly, decreasing the {100} crystal planes from cubes to octahedra, changes the nonenzymatic electro-catalytic activity from highly sensitive to general. PMID:25123202

  14. Health Behavior Theory in Physical Activity Game Apps: A Content Analysis

    PubMed Central

    Moxley, Victor BA; MacDonald, Elizabeth

    2015-01-01

    Background Physical activity games developed for a mobile phone platform are becoming increasingly popular, yet little is known about their content or inclusion of health behavior theory (HBT). Objective The objective of our study was to quantify elements of HBT in physical activity games developed for mobile phones and to assess the relationship between theoretical constructs and various app features. Methods We conducted an analysis of exercise and physical activity game apps in the Apple App Store in the fall of 2014. A total of 52 apps were identified and rated for inclusion of health behavior theoretical constructs using an established theory-based rubric. Each app was coded for 100 theoretical items, containing 5 questions for 20 different constructs. Possible total theory scores ranged from 0 to 100. Descriptive statistics and Spearman correlations were used to describe the HBT score and association with selected app features, respectively. Results The average HBT score in the sample was 14.98 out of 100. One outlier, SuperBetter, scored higher than the other apps with a score of 76. Goal setting, self-monitoring, and self-reward were the most-reported constructs found in the sample. There was no association between either app price and theory score (P=.5074), or number of gamification elements and theory score (P=.5010). However, Superbetter, with the highest HBT score, was also the most expensive app. Conclusions There are few content analyses of serious games for health, but a comparison between these findings and previous content analyses of non-game health apps indicates that physical activity mobile phone games demonstrate higher levels of behavior theory. The most common theoretical constructs found in this sample are known to be efficacious elements in physical activity interventions. It is unclear, however, whether app designers consciously design physical activity mobile phone games with specific constructs in mind; it may be that games lend

  15. A Bayesian Framework for the Classification of Microbial Gene Activity States

    PubMed Central

    Disselkoen, Craig; Greco, Brian; Cook, Kaitlyn; Koch, Kristin; Lerebours, Reginald; Viss, Chase; Cape, Joshua; Held, Elizabeth; Ashenafi, Yonatan; Fischer, Karen; Acosta, Allyson; Cunningham, Mark; Best, Aaron A.; DeJongh, Matthew; Tintle, Nathan

    2016-01-01

    Numerous methods for classifying gene activity states based on gene expression data have been proposed for use in downstream applications, such as incorporating transcriptomics data into metabolic models in order to improve resulting flux predictions. These methods often attempt to classify gene activity for each gene in each experimental condition as belonging to one of two states: active (the gene product is part of an active cellular mechanism) or inactive (the cellular mechanism is not active). These existing methods of classifying gene activity states suffer from multiple limitations, including enforcing unrealistic constraints on the overall proportions of active and inactive genes, failing to leverage a priori knowledge of gene co-regulation, failing to account for differences between genes, and failing to provide statistically meaningful confidence estimates. We propose a flexible Bayesian approach to classifying gene activity states based on a Gaussian mixture model. The model integrates genome-wide transcriptomics data from multiple conditions and information about gene co-regulation to provide activity state confidence estimates for each gene in each condition. We compare the performance of our novel method to existing methods on both simulated data and real data from 907 E. coli gene expression arrays, as well as a comparison with experimentally measured flux values in 29 conditions, demonstrating that our method provides more consistent and accurate results than existing methods across a variety of metrics. PMID:27555837

  16. Harmonised human biomonitoring in Europe: activities towards an EU HBM framework.

    PubMed

    Joas, Reinhard; Casteleyn, Ludwine; Biot, Pierre; Kolossa-Gehring, Marike; Castano, Argelia; Angerer, Juergen; Schoeters, Greet; Sepai, Ovnair; Knudsen, Lisbeth E; Joas, Anke; Horvat, Milena; Bloemen, Louis

    2012-02-01

    Human biomonitoring (HBM) can be an effective tool to assess human exposure to environmental pollutants and potential health effects and is increasingly seen as an essential element in a strategy when integrating health and environment. HBM can be used (i) to prioritise actions and measures for policy making; (ii) to evaluate policy actions aimed at reducing exposure to potentially hazardous environmental stressors; and (iii) to promote more comprehensive health impact assessments of policy options. In support of the European Environment and Health Action Plan 2004-2010, European scientists, experts from authorities and other stakeholders joined forces to work towards developing a functional framework and standards for a coherent HBM in Europe. Within the European coordination action on human biomonitoring, 35 partners from 27 European countries in the COPHES consortium aggregated their experiences and expertise and developed harmonized approaches and recommendations for better comparability of HBM data in Europe via the elaboration of a harmonized study protocol. This protocol is the product of discussion and compromises on the selection of environmental exposures, national environmental health concerns, and political and health priorities. The harmonised approach includes sampling recruitment, and analytical procedures, communication strategies and biobanking initiatives. The protocols and the harmonised approach are a means to increase acceptance and policy support and to in the future to enable determination of time trends. The common pilot study protocol will shortly be tested, adapted and assessed in the framework of the DEMOCOPHES in 17 European countries, including 16 EU Member States. COPHES and DEMOCOPHES constitute important steps towards establishing human biomonitoring as a tool for EU environmental and health policy and to improve quantification of exposure of the general European population to existing and emerging pollutants. PMID:21940209

  17. A theoretical framework for whole-plant carbon assimilation efficiency based on metabolic scaling theory: a test case using Picea seedlings.

    PubMed

    Wang, Zhiqiang; Ji, Mingfei; Deng, Jianming; Milne, Richard I; Ran, Jinzhi; Zhang, Qiang; Fan, Zhexuan; Zhang, Xiaowei; Li, Jiangtao; Huang, Heng; Cheng, Dongliang; Niklas, Karl J

    2015-06-01

    Simultaneous and accurate measurements of whole-plant instantaneous carbon-use efficiency (ICUE) and annual total carbon-use efficiency (TCUE) are difficult to make, especially for trees. One usually estimates ICUE based on the net photosynthetic rate or the assumed proportional relationship between growth efficiency and ICUE. However, thus far, protocols for easily estimating annual TCUE remain problematic. Here, we present a theoretical framework (based on the metabolic scaling theory) to predict whole-plant annual TCUE by directly measuring instantaneous net photosynthetic and respiratory rates. This framework makes four predictions, which were evaluated empirically using seedlings of nine Picea taxa: (i) the flux rates of CO(2) and energy will scale isometrically as a function of plant size, (ii) whole-plant net and gross photosynthetic rates and the net primary productivity will scale isometrically with respect to total leaf mass, (iii) these scaling relationships will be independent of ambient temperature and humidity fluctuations (as measured within an experimental chamber) regardless of the instantaneous net photosynthetic rate or dark respiratory rate, or overall growth rate and (iv) TCUE will scale isometrically with respect to instantaneous efficiency of carbon use (i.e., the latter can be used to predict the former) across diverse species. These predictions were experimentally verified. We also found that the ranking of the nine taxa based on net photosynthetic rates differed from ranking based on either ICUE or TCUE. In addition, the absolute values of ICUE and TCUE significantly differed among the nine taxa, with both ICUE and temperature-corrected ICUE being highest for Picea abies and lowest for Picea schrenkiana. Nevertheless, the data are consistent with the predictions of our general theoretical framework, which can be used to access annual carbon-use efficiency of different species at the level of an individual plant based on simple, direct

  18. A Conceptual Framework for Organizing Active Learning Experiences in Biology Instruction

    ERIC Educational Resources Information Center

    Gardner, Joel; Belland, Brian R.

    2012-01-01

    Introductory biology courses form a cornerstone of undergraduate instruction. However, the predominantly used lecture approach fails to produce higher-order biology learning. Research shows that active learning strategies can increase student learning, yet few biology instructors use all identified active learning strategies. In this paper, we…

  19. A Didactical Framework for Studying Students' and Teachers' Activities when Learning and Teaching Mathematics

    ERIC Educational Resources Information Center

    Robert, Aline

    2012-01-01

    This paper draws an Activity Theoretical frame specific to mathematics at school with reference to both Vygotskian and Piagetian approaches. At a local point of view, the frame is oriented toward analysis of students' mathematical activities in the classroom. This local point of view is extended to a global point of view, to gain access to what…

  20. Framework Programmable Platform for the Advanced Software Development Workstation (FPP/ASDW). Demonstration framework document. Volume 1: Concepts and activity descriptions

    NASA Technical Reports Server (NTRS)

    Mayer, Richard J.; Blinn, Thomas M.; Dewitte, Paul S.; Crump, John W.; Ackley, Keith A.

    1992-01-01

    The Framework Programmable Software Development Platform (FPP) is a project aimed at effectively combining tool and data integration mechanisms with a model of the software development process to provide an intelligent integrated software development environment. Guided by the model, this system development framework will take advantage of an integrated operating environment to automate effectively the management of the software development process so that costly mistakes during the development phase can be eliminated. The Advanced Software Development Workstation (ASDW) program is conducting research into development of advanced technologies for Computer Aided Software Engineering (CASE).