Theoretical framework of community education improvement

Directory of Open Access Journals (Sweden)

Zaúl Brizuela Castillo

2015-05-01

Full Text Available The paper explains the connection between the approach selected for the analysis and development of community education and the contradictions manifested in its theoretical and practical comprehension. As a result, a comprehensive model for community education, describing the theoretical and methodological framework to improve community education, is devised. This framework is based on a conscious organizing of educative influences applied to the regular task of the community under the coordinate action of social institutions and organization that promote the transformational action of the neighborhood assuming a protagonist role in the improvement of the quality of live and morals related to the socialism updating process. The comprehensive model was proved experimentally at District 59 of San Miguel town; the transformation of the community was scientifically registered together with the information gather by means of observation and interviewing. The findings proved the pertinence and feasibility of the proposed model.

Characterising Information Systems in Australia: A Theoretical Framework

Directory of Open Access Journals (Sweden)

Gail Ridley

2006-11-01

Full Text Available The study reported in this volume aims to investigate the state of the Information Systems academic discipline in Australia from a historical and current perspective, collecting evidence across a range of dimensions. To maximise the strategic potential of the study, the results need to be capable of integration, so that the relationships within and across the dimensions and geographical units are understood. A meaningful theoretical framework will help relate the results of the different dimensions of the study to characterise the discipline in the region, and assist in empowering the Australian IS research community. This paper reviewed literature on the development of disciplines, before deriving a theoretical framework for the broader study reported in this volume. The framework considered the current and past state of IS in Australian universities from the perspective of the development of a discipline. The components of the framework were derived and validated through a thematic analysis of both the IS and non-IS literature. This paper also presents brief vignettes of the development of two other related disciplines. The framework developed in this paper, which has been partly guided by Whitley’s Theory of Scientific Change, has been used to analyse data collated from the Australian states and the Australian Capital Territory. The degree of variation in Australian IS as an indication of its “professionalisation”, the nature of its body of knowledge and its mechanisms of control, will be used to frame the analysis. Research reported in several of the papers that follow in this volume has drawn upon the theoretical framework presented below.

Introduction: theoretical framework and research agenda

NARCIS (Netherlands)

Zeitlin, J.; Zeitlin, J.

2015-01-01

This chapter introduces the theoretical framework and research agenda of the book. It provides an overview of the three contemporaneous trends from which the book departs: the development of experimentalist governance within the EU; the EU’s efforts to extend its rules, norms, standards, and

A theoretical framework of organizational change

NARCIS (Netherlands)

Jacobs, G.; Polos, L.; van Witteloostuijn, A.; Christe-Zyse, J.

2013-01-01

Purpose – Organizational change is a risky endeavour. Most change initiatives fall short on their goals and produce high opportunity and process costs, which at times outweigh the content benefits of organizational change. This paper seeks to develop a framework, offering a theoretical toolbox to

A Social-Cognitive Theoretical Framework for Examining Music Teacher Identity

Science.gov (United States)

McClellan, Edward

2017-01-01

The purpose of the study was to examine a diverse range of research literature to provide a social-cognitive theoretical framework as a foundation for definition of identity construction in the music teacher education program. The review of literature may reveal a theoretical framework based around tenets of commonly studied constructs in the…

Plasmon holographic experiments: theoretical framework

International Nuclear Information System (INIS)

Verbeeck, J.; Dyck, D. van; Lichte, H.; Potapov, P.; Schattschneider, P.

2005-01-01

A theoretical framework is described to understand the results of plasmon holography experiments leading to insight in the meaning of the experimental results and pointing out directions for future experiments. The framework is based on the formalism of mutual intensity to describe how coherence is transferred through an optical system. For the inelastic interaction with the object, an expression for the volume plasmon excitations in a free electron gas is used as a model for the behaviour of aluminium. The formalism leads to a clear graphical intuitive tool for understanding the experiments. It becomes evident that the measured coherence is solely related to the angular distribution of the plasmon scattering in the case of bulk plasmons. After describing the framework, the special case of coherence outside a spherical particle is treated and the seemingly controversial idea of a plasmon with a limited coherence length obtained from experiments is clarified

An in-depth analysis of theoretical frameworks for the study of care coordination

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Sabine Van Houdt

2013-06-01

Full Text Available Introduction: Complex chronic conditions often require long-term care from various healthcare professionals. Thus, maintaining quality care requires care coordination. Concepts for the study of care coordination require clarification to develop, study and evaluate coordination strategies. In 2007, the Agency for Healthcare Research and Quality defined care coordination and proposed five theoretical frameworks for exploring care coordination. This study aimed to update current theoretical frameworks and clarify key concepts related to care coordination. Methods: We performed a literature review to update existing theoretical frameworks. An in-depth analysis of these theoretical frameworks was conducted to formulate key concepts related to care coordination.Results: Our literature review found seven previously unidentified theoretical frameworks for studying care coordination. The in-depth analysis identified fourteen key concepts that the theoretical frameworks addressed. These were ‘external factors’, ‘structure’, ‘tasks characteristics’, ‘cultural factors’, ‘knowledge and technology’, ‘need for coordination’, ‘administrative operational processes’, ‘exchange of information’, ‘goals’, ‘roles’, ‘quality of relationship’, ‘patient outcome’, ‘team outcome’, and ‘(interorganizational outcome’.Conclusion: These 14 interrelated key concepts provide a base to develop or choose a framework for studying care coordination. The relational coordination theory and the multi-level framework are interesting as these are the most comprehensive.

Ternary gradient metal-organic frameworks.

Science.gov (United States)

Liu, Chong; Rosi, Nathaniel L

2017-09-08

Gradient MOFs contain directional gradients of either structure or functionality. We have successfully prepared two ternary gradient MOFs based on bMOF-100 analogues, namely bMOF-100/102/106 and bMOF-110/100/102, via cascade ligand exchange reactions. The cubic unit cell parameter discrepancy within an individual ternary gradient MOF crystal is as large as ∼1 nm, demonstrating the impressive compatibility and flexibility of the component MOF materials. Because of the presence of a continuum of unit cells, the pore diameters within individual crystals also change in a gradient fashion from ∼2.5 nm to ∼3.0 nm for bMOF-100/102/106, and from ∼2.2 nm to ∼2.7 nm for bMOF-110/100/102, indicating significant porosity gradients. Like previously reported binary gradient MOFs, the composition of the ternary gradient MOFs can be easily controlled by adjusting the reaction conditions. Finally, X-ray diffraction and microspectrophotometry were used to analyse fractured gradient MOF crystals by comparing unit cell parameters and absorbance spectra at different locations, thus revealing the profile of heterogeneity (i.e. gradient distribution of properties) and further confirming the formation of ternary gradient MOFs.

Theoretical frameworks informing family-based child and adolescent obesity interventions

DEFF Research Database (Denmark)

Alulis, Sarah; Grabowski, Dan

2017-01-01

into focus. However, the use of theoretical frameworks to strengthen these interventions is rare and very uneven. OBJECTIVE AND METHOD: To conduct a qualitative meta-synthesis of family-based interventions for child and adolescent obesity to identify the theoretical frameworks applied, thus understanding how...... inconsistencies and a significant void between research results and health care practice. Based on the analysis, this article proposes three themes to be used as focus points when designing future interventions and when selecting theories for the development of solid, theory-based frameworks for application...... cognitive, self-efficacy and Family Systems Theory appeared most frequently. The remaining 24 were classified as theory-related as theoretical elements of self-monitoring; stimulus control, reinforcement and modelling were used. CONCLUSION: The designs of family-based interventions reveal numerous...

Theoretical and Conceptual Frameworks Used in Research on Family-School Partnerships

Science.gov (United States)

Yamauchi, Lois A.; Ponte, Eva; Ratliffe, Katherine T.; Traynor, Kevin

2017-01-01

This study investigated the theoretical frameworks used to frame research on family-school partnerships over a five-year period. Although many researchers have described their theoretical approaches, little has been written about the diversity of frameworks used and how they are applied. Coders analyzed 215 journal articles published from 2007 to…

A framework for biodynamic feedthrough analysis--part I: theoretical foundations.

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Venrooij, Joost; van Paassen, Marinus M; Mulder, Mark; Abbink, David A; Mulder, Max; van der Helm, Frans C T; Bulthoff, Heinrich H

2014-09-01

Biodynamic feedthrough (BDFT) is a complex phenomenon, which has been studied for several decades. However, there is little consensus on how to approach the BDFT problem in terms of definitions, nomenclature, and mathematical descriptions. In this paper, a framework for biodynamic feedthrough analysis is presented. The goal of this framework is two-fold. First, it provides some common ground between the seemingly large range of different approaches existing in the BDFT literature. Second, the framework itself allows for gaining new insights into BDFT phenomena. It will be shown how relevant signals can be obtained from measurement, how different BDFT dynamics can be derived from them, and how these different dynamics are related. Using the framework, BDFT can be dissected into several dynamical relationships, each relevant in understanding BDFT phenomena in more detail. The presentation of the BDFT framework is divided into two parts. This paper, Part I, addresses the theoretical foundations of the framework. Part II, which is also published in this issue, addresses the validation of the framework. The work is presented in two separate papers to allow for a detailed discussion of both the framework's theoretical background and its validation.

Cosmopolitanism: Extending Our Theoretical Framework for Transcultural Technical Communication Research and Teaching

Science.gov (United States)

Palmer, Zsuzsanna Bacsa

2013-01-01

The effects of globalization on communication products and processes have resulted in document features and interactional practices that are sometimes difficult to describe within current theoretical frameworks of inter/transcultural technical communication. Although it has been recognized in our field that the old theoretical frameworks and…

The Extended Likeability Framework: A Theoretical Framework for and a Practical Case of Designing Likeable Media Applications for Preschoolers

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Vero vanden Abeele

2008-01-01

Full Text Available A theoretical framework and practical case for designing likeable interactive media applications for preschoolers in the home environment are introduced. First, we elaborate on the theoretical framework. We introduce the uses and gratifications paradigm (U&G. We argue that U&G is a good approach to researching likeability of media applications. Next, we complete the U&G framework with expectancy-value (EV theory. EV theory helps us move from theoretical insights to concrete design guidelines. Together, the U&G framework and the EV model form the foundation of our extended likeability framework for the design and evaluation of interactive media applications, for preschoolers in the home environment. Finally, we demonstrate a practical case of our extended likeability framework via the research project CuTI. The CuTI project aims at revealing those particular user gratifications and design attributes that are important to support playful behaviour and fun activities of preschoolers in the home environment.

A Theoretically Consistent Framework for Modelling Lagrangian Particle Deposition in Plant Canopies

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Bailey, Brian N.; Stoll, Rob; Pardyjak, Eric R.

2018-06-01

We present a theoretically consistent framework for modelling Lagrangian particle deposition in plant canopies. The primary focus is on describing the probability of particles encountering canopy elements (i.e., potential deposition), and provides a consistent means for including the effects of imperfect deposition through any appropriate sub-model for deposition efficiency. Some aspects of the framework draw upon an analogy to radiation propagation through a turbid medium with which to develop model theory. The present method is compared against one of the most commonly used heuristic Lagrangian frameworks, namely that originally developed by Legg and Powell (Agricultural Meteorology, 1979, Vol. 20, 47-67), which is shown to be theoretically inconsistent. A recommendation is made to discontinue the use of this heuristic approach in favour of the theoretically consistent framework developed herein, which is no more difficult to apply under equivalent assumptions. The proposed framework has the additional advantage that it can be applied to arbitrary canopy geometries given readily measurable parameters describing vegetation structure.

Intellect: a theoretical framework for personality traits related to intellectual achievements.

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Mussel, Patrick

2013-05-01

The present article develops a theoretical framework for the structure of personality traits related to intellectual achievements. We postulate a 2-dimensional model, differentiating between 2 processes (Seek and Conquer) and 3 operations (Think, Learn, and Create). The framework was operationalized by a newly developed measure, which was validated based on 2 samples. Subsequently, in 3 studies (overall N = 1,478), the 2-dimensional structure of the Intellect framework was generally supported. Additionally, subdimensions of the Intellect framework specifically predicted conceptually related criteria, including scholastic performance, vocational interest, and leisure activities. Furthermore, results from multidimensional scaling and higher order confirmatory factor analyses show that the framework allows for the incorporation of several constructs that have been proposed on different theoretical backgrounds, such as need for cognition, typical intellectual engagement, curiosity, intrinsic motivation, goal orientation, and openness to ideas. It is concluded that based on the Intellect framework, these constructs, which have been researched separately in the literature, can be meaningfully integrated.

A Theoretical Framework for Studying Adolescent Contraceptive Use.

Science.gov (United States)

Urberg, Kathryn A.

1982-01-01

Presents a theoretical framework for viewing adolescent contraceptive usage. The problem-solving process is used for developmentally examining the competencies that must be present for effective contraceptive use, including: problem recognition, motivation, generation of alternatives, decision making and implementation. Each aspect is discussed…

A typology of design knowledge: a theoretical framework

NARCIS (Netherlands)

Mueller, Roland; Thoring, Katja

2010-01-01

This paper is a theoretical approach to structure design-specific knowledge into a framework, which can be used within the context of organizational and societal development. We conducted an extensive literature review about existing definitions of design knowledge, and knowledge in general. Based

Toward a theoretical framework for trustworthy cyber sensing

Science.gov (United States)

Xu, Shouhuai

2010-04-01

Cyberspace is an indispensable part of the economy and society, but has been "polluted" with many compromised computers that can be abused to launch further attacks against the others. Since it is likely that there always are compromised computers, it is important to be aware of the (dynamic) cyber security-related situation, which is however challenging because cyberspace is an extremely large-scale complex system. Our project aims to investigate a theoretical framework for trustworthy cyber sensing. With the perspective of treating cyberspace as a large-scale complex system, the core question we aim to address is: What would be a competent theoretical (mathematical and algorithmic) framework for designing, analyzing, deploying, managing, and adapting cyber sensor systems so as to provide trustworthy information or input to the higher layer of cyber situation-awareness management, even in the presence of sophisticated malicious attacks against the cyber sensor systems?

Validation of the theoretical domains framework for use in behaviour change and implementation research.

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Cane, James; O'Connor, Denise; Michie, Susan

2012-04-24

An integrative theoretical framework, developed for cross-disciplinary implementation and other behaviour change research, has been applied across a wide range of clinical situations. This study tests the validity of this framework. Validity was investigated by behavioural experts sorting 112 unique theoretical constructs using closed and open sort tasks. The extent of replication was tested by Discriminant Content Validation and Fuzzy Cluster Analysis. There was good support for a refinement of the framework comprising 14 domains of theoretical constructs (average silhouette value 0.29): 'Knowledge', 'Skills', 'Social/Professional Role and Identity', 'Beliefs about Capabilities', 'Optimism', 'Beliefs about Consequences', 'Reinforcement', 'Intentions', 'Goals', 'Memory, Attention and Decision Processes', 'Environmental Context and Resources', 'Social Influences', 'Emotions', and 'Behavioural Regulation'. The refined Theoretical Domains Framework has a strengthened empirical base and provides a method for theoretically assessing implementation problems, as well as professional and other health-related behaviours as a basis for intervention development.

A theoretical framework for an access programme encompassing ...

African Journals Online (AJOL)

A theoretical framework for an access programme encompassing further education training: remedy for educational wastage? ... learners who have dropped out of school without completing their secondary-school education, there are the special needs of adult learners in the workplace that must be taken into consideration.

The probabilistic innovation theoretical framework

Directory of Open Access Journals (Sweden)

Chris W. Callaghan

2017-07-01

Full Text Available Background: Despite technological advances that offer new opportunities for solving societal problems in real time, knowledge management theory development has largely not kept pace with these developments. This article seeks to offer useful insights into how more effective theory development in this area could be enabled. Aim: This article suggests different streams of literature for inclusion into a theoretical framework for an emerging stream of research, termed ‘probabilistic innovation’, which seeks to develop a system of real-time research capability. The objective of this research is therefore to provide a synthesis of a range of diverse literatures, and to provide useful insights into how research enabled by crowdsourced research and development can potentially be used to address serious knowledge problems in real time. Setting: This research suggests that knowledge management theory can provide an anchor for a new stream of research contributing to the development of real-time knowledge problem solving. Methods: This conceptual article seeks to re-conceptualise the problem of real-time research and locate this knowledge problem in relation to a host of rapidly developing streams of literature. In doing so, a novel perspective of societal problem-solving is enabled. Results: An analysis of theory and literature suggests that certain rapidly developing streams of literature might more effectively contribute to societally important real-time research problem solving if these steams are united under a theoretical framework with this goal as its explicit focus. Conclusion: Although the goal of real-time research is as yet not attainable, research that contributes to its attainment may ultimately make an important contribution to society.

Using a Theoretical Framework of Institutional Culture to Analyse an Institutional Strategy Document

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Jacobs, Anthea Hydi Maxine

2016-01-01

This paper builds on a conceptual analysis of institutional culture in higher education. A theoretical framework was proposed to analyse institutional documents of two higher education institutions in the Western Cape, for the period 2002 to 2012 (Jacobs 2012). The elements of this theoretical framework are "shared values and beliefs",…

Improving utilization of conceptual and theoretical framework in ...

African Journals Online (AJOL)

The Nursing and Midwifery Councils of many nations including Nigeria and nursing departments of various Universities and institutions have made it mandatory that conceptual and theoretical framework are used to guide Nursing research presented as part of the requirements for the award of certificates and degrees.

Theoretical framework to study exercise motivation for breast cancer risk reduction.

Science.gov (United States)

Wood, Maureen E

2008-01-01

To identify an appropriate theoretical framework to study exercise motivation for breast cancer risk reduction among high-risk women. An extensive review of the literature was conducted to gather relevant information pertaining to the Health Promotion Model, self-determination theory, social cognitive theory, Health Belief Model, Transtheoretical Model, theory of planned behavior, and protection motivation theory. An iterative approach was used to summarize the literature related to exercise motivation within each theoretical framework. Protection motivation theory could be used to examine the effects of perceived risk and self-efficacy in motivating women to exercise to facilitate health-related behavioral change. Evidence-based research within a chosen theoretical model can aid practitioners when making practical recommendations to reduce breast cancer risk.

Innovation value chain capability in Malaysian-owned company: A theoretical framework

Science.gov (United States)

Abidin, Norkisme Zainal; Suradi, Nur Riza Mohd

2014-09-01

Good quality products or services are no longer adequate to guarantee the sustainability of a company in the present competitive business. Prior research has developed various innovation models with the hope to better understand the innovativeness of the company. Due to countless definitions, indicators, factors, parameter and approaches in the study of innovation, it is difficult to ensure which one will best suit the Malaysian-owned company innovativeness. This paper aims to provide a theoretical background to support the framework of the innovation value chain capability in Malaysian-owned Company. The theoretical framework was based on the literature reviews, expert interviews and focus group study. The framework will be used to predict and assess the innovation value chain capability in Malaysian-owned company.

Couples coping with cancer: exploration of theoretical frameworks from dyadic studies.

Science.gov (United States)

Regan, Tim W; Lambert, Sylvie D; Kelly, Brian; Falconier, Mariana; Kissane, David; Levesque, Janelle V

2015-12-01

A diagnosis of cancer and subsequent treatment are distressing not only for the person directly affected, but also for their intimate partner. The aim of this review is to (a) identify the main theoretical frameworks underpinning research addressing dyadic coping among couples affected by cancer, (b) summarise the evidence supporting the concepts described in these theoretical frameworks, and (c) examine the similarities and differences between these theoretical perspectives. A literature search was undertaken to identify descriptive studies published between 1990 and 2013 (English and French) that examined the interdependence of patients' and partners' coping, and the impact of coping on psychosocial outcomes. Data were extracted using a standardised form and reviewed by three of the authors. Twenty-three peer-reviewed manuscripts were identified, from which seven theoretical perspectives were derived: Relationship-Focused Coping, Transactional Model of Stress and Coping, Systemic-Transactional Model (STM) of dyadic coping, Collaborative Coping, Relationship Intimacy model, Communication models, and Coping Congruence. Although these theoretical perspectives emphasised different aspects of coping, a number of conceptual commonalities were noted. This review identified key theoretical frameworks of dyadic coping used in cancer. Evidence indicates that responses within the couple that inhibit open communication between partner and patient are likely to have an adverse impact on psychosocial outcomes. Models that incorporate the interdependence of emotional responses and coping behaviours within couples have an emerging evidence base in psycho-oncology and may have greatest validity and clinical utility in this setting. Copyright © 2015 John Wiley & Sons, Ltd.

Recycling, reducing and reusing: A theoretical framework

International Nuclear Information System (INIS)

Kubursi, A.A.; Butterfield, D.W.

1990-01-01

Macroeconomic models are generally based on a particular national income accounting framework. The current approach treats waste and pollution generation in such a way that any increase in these activities increases directly the gross domestic product of the economy. A reformulation is suggested for the accounting framework so as to treat waste management and pollution abatement as services to business whose costs should be charged against business revenue. Even such costs to households may be considered as costs to output. In this way such expenses appear as a cost to society and not as a final output. A new theoretical framework is developed to correspond to the reformulated accounting principle that allows clear identification of recycling activity and waste management. The rectangular input-output framework is particularly suited for this treatment as it allows different industries to produce the same output and identifies different commodities as inputs in the production of the same output. With the new framework, it is possible to examine the socioeconomic consequences of increased use and production of recyclables. Equally important is the ability to assess the relative efficiency of alternative policies to reuse or reduce the use of products and resources through price incentives and full cost charges. 2 tabs

A Theoretical Framework for Goal-directed Care within the Prison System

NARCIS (Netherlands)

Bulten, B.H.; Vissers, A.W.T.M.; Oei, K.

2008-01-01

Mental health care in prisons involves many stakeholders. As a consequence, the goals involved are divergent but there is no sound theoretical framework that accounts for the complexity of care in prison. This paper considers a broad theory and its conceptual framework that differentiates between

Internet Use and Cognitive Development: A Theoretical Framework

Science.gov (United States)

Johnson, Genevieve

2006-01-01

The number of children and adolescents accessing the Internet as well as the amount of time online are steadily increasing. The most common online activities include playing video games, accessing web sites, and communicating via chat rooms, email, and instant messaging. A theoretical framework for understanding the effects of Internet use on…

Theoretical multi-tier trust framework for the geospatial domain

CSIR Research Space (South Africa)

Umuhoza, D

2010-01-01

Full Text Available chain or workflow from data acquisition to knowledge discovery. The author’s present work in progress of a theoretical multi-tier trust framework for processing chain from data acquisition to knowledge discovery in geospatial domain. Holistic trust...

Temporal discounting in life cycle assessment: A critical review and theoretical framework

International Nuclear Information System (INIS)

Yuan, Chris; Wang, Endong; Zhai, Qiang; Yang, Fan

2015-01-01

Temporal homogeneity of inventory data is one of the major problems in life cycle assessment (LCA). Addressing temporal homogeneity of life cycle inventory data is important in reducing the uncertainties and improving the reliability of LCA results. This paper attempts to present a critical review and discussion on the fundamental issues of temporal homogeneity in conventional LCA and propose a theoretical framework for temporal discounting in LCA. Theoretical perspectives for temporal discounting in life cycle inventory analysis are discussed first based on the key elements of a scientific mechanism for temporal discounting. Then generic procedures for performing temporal discounting in LCA is derived and proposed based on the nature of the LCA method and the identified key elements of a scientific temporal discounting method. A five-step framework is proposed and reported in details based on the technical methods and procedures needed to perform a temporal discounting in life cycle inventory analysis. Challenges and possible solutions are also identified and discussed for the technical procedure and scientific accomplishment of each step within the framework. - Highlights: • A critical review for temporal homogeneity problem of life cycle inventory data • A theoretical framework for performing temporal discounting on inventory data • Methods provided to accomplish each step of the temporal discounting framework

Theoretical Framework of Leadership in Higher Education of England and Wales

Science.gov (United States)

Mukan, Nataliya; Havrylyuk, Marianna; Stolyarchuk, Lesia

2015-01-01

In the article the theoretical framework of leadership in higher education of England and Wales has been studied. The main objectives of the article are defined as analysis of scientific and pedagogical literature, which highlights different aspects of the problem under research; characteristic of the theoretical fundamentals of educational…

Professional Development and Use of Digital Technologies by Science Teachers: a Review of Theoretical Frameworks

Science.gov (United States)

Fernandes, Geraldo W. Rocha; Rodrigues, António M.; Ferreira, Carlos Alberto

2018-03-01

This article aims to characterise the research on science teachers' professional development programs that support the use of Information and Communication Technologies (ICTs) and the main trends concerning the theoretical frameworks (theoretical foundation, literature review or background) that underpin these studies. Through a systematic review of the literature, 76 articles were found and divided into two axes on training science teachers and the use of digital technologies with their categories. The first axis (characterisation of articles) presents the category key features that characterise the articles selected (major subjects, training and actions for the professional development and major ICT tools and digital resources). The second axis (trends of theoretical frameworks) has three categories organised in theoretical frameworks that emphasise the following: (a) the digital technologies, (b) prospects of curricular renewal and (c) cognitive processes. It also characterised a group of articles with theoretical frameworks that contain multiple elements without deepening them or that even lack a theoretical framework that supports the studies. In this review, we found that many professional development programs for teachers still use inadequate strategies for bringing about change in teacher practices. New professional development proposals are emerging with the objective of minimising such difficulties and this analysis could be a helpful tool to restructure those proposals.

Educational Communities of Inquiry: Theoretical Framework, Research and Practice

Science.gov (United States)

Akyol, Zehra; Garrison, D. Randy

2013-01-01

Communications technologies have been continuously integrated into learning and training environments which has revealed the need for a clear understanding of the process. The Community of Inquiry (COI) Theoretical Framework has a philosophical foundation which provides planned guidelines and principles to development useful learning environments…

Game theoretical framework in determining house prices

Science.gov (United States)

Saiddin, Nor Syuhadah; Zaibidi, Nerda Zura; Sulaiman, Nor Intan Saniah; Abidin, Norhaslinda Zainal

2017-11-01

Housing is a vital component in world's economic development as it provides big contribution of the wealth. The issue of high house prices, worrying several parties, especially middle income buyers in Malaysia. Basically, in housing, there are three main parties involved; buyer, property developer and government. Interaction between those parties will give an impact to the housing market, specifically house prices. The complexity of the interaction has increased due to the differences in each party's preferences and interest. In this research, the main objective is to develop the framework of the interactions among those parties using game theoretical approach. To do so, the preferences and target of each party are investigated and their constraints are established. From the framework, it offers some ideas on how the interaction occurs and how it affect the house prices.

Obesity in sub-Saharan Africa: development of an ecological theoretical framework.

Science.gov (United States)

Scott, Alison; Ejikeme, Chinwe Stella; Clottey, Emmanuel Nii; Thomas, Joy Goens

2013-03-01

The prevalence of overweight and obesity is increasing in sub-Saharan Africa (SSA). There is a need for theoretical frameworks to catalyze further research and to inform the development of multi-level, context-appropriate interventions. In this commentary, we propose a preliminary ecological theoretical framework to conceptualize factors that contribute to increases in overweight and obesity in SSA. The framework is based on a Causality Continuum model [Coreil et al. Social and Behavioral Foundations of Public Health. Sage Publications, Thousand Oaks] that considers distant, intermediate and proximate influences. The influences incorporated in the model include globalization and urbanization as distant factors; occupation, social relationships, built environment and cultural perceptions of weight as intermediate factors and caloric intake, physical inactivity and genetics as proximate factors. The model illustrates the interaction of factors along a continuum, from the individual to the global marketplace, in shaping trends in overweight and obesity in SSA. The framework will be presented, each influence elucidated and implications for research and intervention development discussed. There is a tremendous need for further research on obesity in SSA. An improved evidence base will serve to validate and develop the proposed framework further.

Quantifying heterogeneity attributable to polythetic diagnostic criteria: theoretical framework and empirical application.

Science.gov (United States)

Olbert, Charles M; Gala, Gary J; Tupler, Larry A

2014-05-01

Heterogeneity within psychiatric disorders is both theoretically and practically problematic: For many disorders, it is possible for 2 individuals to share very few or even no symptoms in common yet share the same diagnosis. Polythetic diagnostic criteria have long been recognized to contribute to this heterogeneity, yet no unified theoretical understanding of the coherence of symptom criteria sets currently exists. A general framework for analyzing the logical and mathematical structure, coherence, and diversity of Diagnostic and Statistical Manual diagnostic categories (DSM-5 and DSM-IV-TR) is proposed, drawing from combinatorial mathematics, set theory, and information theory. Theoretical application of this framework to 18 diagnostic categories indicates that in most categories, 2 individuals with the same diagnosis may share no symptoms in common, and that any 2 theoretically possible symptom combinations will share on average less than half their symptoms. Application of this framework to 2 large empirical datasets indicates that patients who meet symptom criteria for major depressive disorder and posttraumatic stress disorder tend to share approximately three-fifths of symptoms in common. For both disorders in each of the datasets, pairs of individuals who shared no common symptoms were observed. Any 2 individuals with either diagnosis were unlikely to exhibit identical symptomatology. The theoretical and empirical results stemming from this approach have substantive implications for etiological research into, and measurement of, psychiatric disorders.

Exploring How Globalization Shapes Education: Methodology and Theoretical Framework

Science.gov (United States)

Pan, Su-Yan

2010-01-01

This is a commentary on some major issues raised in Carter and Dediwalage's "Globalisation and science education: The case of "Sustainability by the bay"" (this issue), particularly their methodology and theoretical framework for understanding how globalisation shapes education (including science education). While acknowledging the authors'…

Theoretical Models and Operational Frameworks in Public Health Ethics

Science.gov (United States)

Petrini, Carlo

2010-01-01

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

Patient Autonomy in a High-Tech Care Context - A Theoretical Framework.

Science.gov (United States)

Lindberg, Catharina; Fagerström, Cecilia; Willman, Ania

2018-06-12

To synthesise and interpret previous findings with the aim of developing a theoretical framework for patient autonomy in a high-tech care context. Putting the somewhat abstract concept of patient autonomy into practice can prove difficult since when it is highlighted in healthcare literature the patient perspective is often invisible. Autonomy presumes that a person has experience, education, self-discipline and decision-making capacity. Reference to autonomy in relation to patients in high-tech care environments could therefore be considered paradoxical, as in most cases these persons are vulnerable, with impaired physical and/or metacognitive capacity, thus making extended knowledge of patient autonomy for these persons even more important. Theory development. The basic approaches in theory development by Walker and Avant were used to create a theoretical framework through an amalgamation of the results from three qualitative studies conducted previously by the same research group. A theoretical framework - the control-partnership-transition framework - was delineated disclosing different parts co-creating the prerequisites for patient autonomy in high-tech care environments. Assumptions and propositional statements that guide theory development were also outlined, as were guiding principles for use in day-to-day nursing care. Four strategies used by patients were revealed: the strategy of control, the strategy of partnership, the strategy of trust, and the strategy of transition. An extended knowledge base, founded on theoretical reasoning about patient autonomy, could facilitate nursing care that would allow people to remain/become autonomous in the role of patient in high-tech care environments. The control-partnership-transition framework would be of help in supporting and defending patient autonomy when caring for individual patients, as it provides an understanding of the strategies employed by patients to achieve autonomy in high-tech care contexts. The

The Importance of Theoretical Frameworks and Mathematical Constructs in Designing Digital Tools

Science.gov (United States)

Trinter, Christine

2016-01-01

The increase in availability of educational technologies over the past few decades has not only led to new practice in teaching mathematics but also to new perspectives in research, methodologies, and theoretical frameworks within mathematics education. Hence, the amalgamation of theoretical and pragmatic considerations in digital tool design…

Theoretical Models and Operational Frameworks in Public Health Ethics

Directory of Open Access Journals (Sweden)

Carlo Petrini

2010-01-01

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

Exploring neoliberal social-reproduction: a working theoretical framework

OpenAIRE

Leyva, Rodolfo

2012-01-01

This article proposes a working theoretical framework to explain and explore processes of neoliberal social reproduction. I focus on the interplay between neoliberal political-economic discourses and practices, contemporary Western media-culture, and individual agency. I make the case that research concerned with the hegemony of neoliberalism and its effects on culture and subjectivity needs to take an interdisciplinary approach that rejects the longstanding structure and agency dichotomy. To...

Validation of the theoretical domains framework for use in behaviour change and implementation research

OpenAIRE

Cane, James E.; O'Connor, Denise; Michie, Susan

2012-01-01

Abstract Background An integrative theoretical framework, developed for cross-disciplinary implementation and other behaviour change research, has been applied across a wide range of clinical situations. This study tests the validity of this framework. Methods Validity was investigated by behavioural experts sorting 112 unique theoretical constructs using closed and open sort tasks. The extent of replication was tested by Discriminant Content Validation and Fuzzy Cluster Analysis. Results The...

Episodic Laryngeal Breathing Disorders: Literature Review and Proposal of Preliminary Theoretical Framework.

Science.gov (United States)

Shembel, Adrianna C; Sandage, Mary J; Verdolini Abbott, Katherine

2017-01-01

The purposes of this literature review were (1) to identify and assess frameworks for clinical characterization of episodic laryngeal breathing disorders (ELBD) and their subtypes, (2) to integrate concepts from these frameworks into a novel theoretical paradigm, and (3) to provide a preliminary algorithm to classify clinical features of ELBD for future study of its clinical manifestations and underlying pathophysiological mechanisms. This is a literature review. Peer-reviewed literature from 1983 to 2015 pertaining to models for ELBD was searched using Pubmed, Ovid, Proquest, Cochrane Database of Systematic Reviews, and Google Scholar. Theoretical models for ELBD were identified, evaluated, and integrated into a novel comprehensive framework. Consensus across three salient models provided a working definition and inclusionary criteria for ELBD within the new framework. Inconsistencies and discrepancies within the models provided an analytic platform for future research. Comparison among three conceptual models-(1) Irritable larynx syndrome, (2) Dichotomous triggers, and (3) Periodic occurrence of laryngeal obstruction-showed that the models uniformly consider ELBD to involve episodic laryngeal obstruction causing dyspnea. The models differed in their description of source of dyspnea, in their inclusion of corollary behaviors, in their inclusion of other laryngeal-based behaviors (eg, cough), and types of triggers. The proposed integrated theoretical framework for ELBD provides a preliminary systematic platform for the identification of key clinical feature patterns indicative of ELBD and associated clinical subgroups. This algorithmic paradigm should evolve with better understanding of this spectrum of disorders and its underlying pathophysiological mechanisms. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

Death of a Simulated Pediatric Patient: Toward a More Robust Theoretical Framework.

Science.gov (United States)

McBride, Mary E; Schinasi, Dana Aronson; Moga, Michael Alice; Tripathy, Shreepada; Calhoun, Aaron

2017-12-01

A theoretical framework was recently proposed that encapsulates learner responses to simulated death due to action or inaction in the pediatric context. This framework, however, was developed at an institution that allows simulated death and thus does not address the experience of those centers at which this technique is not used. To address this, we performed a parallel qualitative study with the intent of augmenting the initial framework. We conducted focus groups, using a constructivist grounded theory approach, using physicians and nurses who have experienced a simulated cardiac arrest. The participants were recruited via e-mail. Transcripts were analyzed by coders blinded to the original framework to generate a list of provisional themes that were iteratively refined. These themes were then compared with the themes from the original article and used to derive a consensus model that incorporated the most relevant features of each. Focus group data yielded 7 themes. Six were similar to those developed in the original framework. One important exception was noted; however, those learners not exposed to patient death due to action or inaction often felt that the mannequin's survival was artificial. This additional theme was incorporated into a revised framework. The original framework addresses most aspects of learner reactions to simulated death. Our work suggests that adding the theme pertaining to the lack of realism that can be perceived when the mannequin is unexpectedly saved results in a more robust theoretical framework transferable to centers that do not allow mannequin death.

Multi-scale theoretical investigation of hydrogen storage in covalent organic frameworks.

Science.gov (United States)

Tylianakis, Emmanuel; Klontzas, Emmanouel; Froudakis, George E

2011-03-01

The quest for efficient hydrogen storage materials has been the limiting step towards the commercialization of hydrogen as an energy carrier and has attracted a lot of attention from the scientific community. Sophisticated multi-scale theoretical techniques have been considered as a valuable tool for the prediction of materials storage properties. Such techniques have also been used for the investigation of hydrogen storage in a novel category of porous materials known as Covalent Organic Frameworks (COFs). These framework materials are consisted of light elements and are characterized by exceptional physicochemical properties such as large surface areas and pore volumes. Combinations of ab initio, Molecular Dynamics (MD) and Grand Canonical Monte-Carlo (GCMC) calculations have been performed to investigate the hydrogen adsorption in these ultra-light materials. The purpose of the present review is to summarize the theoretical hydrogen storage studies that have been published after the discovery of COFs. Experimental and theoretical studies have proven that COFs have comparable or better hydrogen storage abilities than other competitive materials such as MOF. The key factors that can lead to the improvement of the hydrogen storage properties of COFs are highlighted, accompanied with some recently presented theoretical multi-scale studies concerning these factors.

A Theoretical Framework towards Understanding of Emotional and Behavioural Difficulties

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Poulou, Maria S.

2014-01-01

Children's emotional and behavioural difficulties are the result of multiple individual, social and contextual factors working in concert. The current paper proposes a theoretical framework to interpret students' emotional and behavioural difficulties in schools, by taking into consideration teacher-student relationships, students'…

Evidence - competence - discourse: the theoretical framework of the multi-centre clinical ethics support project METAP.

Science.gov (United States)

Reiter-Theil, Stella; Mertz, Marcel; Schürmann, Jan; Stingelin Giles, Nicola; Meyer-Zehnder, Barbara

2011-09-01

In this paper we assume that 'theory' is important for Clinical Ethics Support Services (CESS). We will argue that the underlying implicit theory should be reflected. Moreover, we suggest that the theoretical components on which any clinical ethics support (CES) relies should be explicitly articulated in order to enhance the quality of CES. A theoretical framework appropriate for CES will be necessarily complex and should include ethical (both descriptive and normative), metaethical and organizational components. The various forms of CES that exist in North-America and in Europe show their underlying theory more or less explicitly, with most of them referring to some kind of theoretical components including 'how-to' questions (methodology), organizational issues (implementation), problem analysis (phenomenology or typology of problems), and related ethical issues such as end-of-life decisions (major ethical topics). In order to illustrate and explain the theoretical framework that we are suggesting for our own CES project METAP, we will outline this project which has been established in a multi-centre context in several healthcare institutions. We conceptualize three 'pillars' as the major components of our theoretical framework: (1) evidence, (2) competence, and (3) discourse. As a whole, the framework is aimed at developing a foundation of our CES project METAP. We conclude that this specific integration of theoretical components is a promising model for the fruitful further development of CES. © 2011 Blackwell Publishing Ltd.

Theories of behaviour change synthesised into a set of theoretical groupings: introducing a thematic series on the theoretical domains framework.

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Francis, Jill J; O'Connor, Denise; Curran, Janet

2012-04-24

Behaviour change is key to increasing the uptake of evidence into healthcare practice. Designing behaviour-change interventions first requires problem analysis, ideally informed by theory. Yet the large number of partly overlapping theories of behaviour makes it difficult to select the most appropriate theory. The need for an overarching theoretical framework of behaviour change was addressed in research in which 128 explanatory constructs from 33 theories of behaviour were identified and grouped. The resulting Theoretical Domains Framework (TDF) appears to be a helpful basis for investigating implementation problems. Research groups in several countries have conducted TDF-based studies. It seems timely to bring together the experience of these teams in a thematic series to demonstrate further applications and to report key developments. This overview article describes the TDF, provides a brief critique of the framework, and introduces this thematic series.In a brief review to assess the extent of TDF-based research, we identified 133 papers that cite the framework. Of these, 17 used the TDF as the basis for empirical studies to explore health professionals' behaviour. The identified papers provide evidence of the impact of the TDF on implementation research. Two major strengths of the framework are its theoretical coverage and its capacity to elicit beliefs that could signify key mediators of behaviour change. The TDF provides a useful conceptual basis for assessing implementation problems, designing interventions to enhance healthcare practice, and understanding behaviour-change processes. We discuss limitations and research challenges and introduce papers in this series.

Understanding Decision-Making in Specialized Domestic Violence Courts: Can Contemporary Theoretical Frameworks Help Guide These Decisions?

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Pinchevsky, Gillian M

2016-05-22

This study fills a gap in the literature by exploring the utility of contemporary courtroom theoretical frameworks-uncertainty avoidance, causal attribution, and focal concerns-for explaining decision-making in specialized domestic violence courts. Using data from two specialized domestic violence courts, this study explores the predictors of prosecutorial and judicial decision-making and the extent to which these factors are congruent with theoretical frameworks often used in studies of court processing. Findings suggest that these theoretical frameworks only partially help explain decision-making in the courts under study. A discussion of the findings and implications for future research is provided. © The Author(s) 2016.

Factors Influencing the Use of Learning Management System in Saudi Arabian Higher Education: A Theoretical Framework

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Asiri, Mohammed J. Sherbib; Mahmud, Rosnaini bt; Bakar, Kamariah Abu; Ayub, Ahmad Fauzi bin Mohd

2012-01-01

The purpose of this paper is to present the theoretical framework underlying a research on factors that influence utilization of the Jusur Learning Management System (Jusur LMS) in Saudi Arabian public universities. Development of the theoretical framework was done based on library research approach. Initially, the existing literature relevant to…

A density gradient theory based method for surface tension calculations

DEFF Research Database (Denmark)

Liang, Xiaodong; Michelsen, Michael Locht; Kontogeorgis, Georgios

2016-01-01

The density gradient theory has been becoming a widely used framework for calculating surface tension, within which the same equation of state is used for the interface and bulk phases, because it is a theoretically sound, consistent and computationally affordable approach. Based on the observation...... that the optimal density path from the geometric mean density gradient theory passes the saddle point of the tangent plane distance to the bulk phases, we propose to estimate surface tension with an approximate density path profile that goes through this saddle point. The linear density gradient theory, which...... assumes linearly distributed densities between the two bulk phases, has also been investigated. Numerical problems do not occur with these density path profiles. These two approximation methods together with the full density gradient theory have been used to calculate the surface tension of various...

An integrated organisation-wide data quality management and information governance framework: theoretical underpinnings.

Science.gov (United States)

Liaw, Siaw-Teng; Pearce, Christopher; Liyanage, Harshana; Liaw, Gladys S S; de Lusignan, Simon

2014-01-01

Increasing investment in eHealth aims to improve cost effectiveness and safety of care. Data extraction and aggregation can create new data products to improve professional practice and provide feedback to improve the quality of source data. A previous systematic review concluded that locally relevant clinical indicators and use of clinical record systems could support clinical governance. We aimed to extend and update the review with a theoretical framework. We searched PubMed, Medline, Web of Science, ABI Inform (Proquest) and Business Source Premier (EBSCO) using the terms curation, information ecosystem, data quality management (DQM), data governance, information governance (IG) and data stewardship. We focused on and analysed the scope of DQM and IG processes, theoretical frameworks, and determinants of the processing, quality assurance, presentation and sharing of data across the enterprise. There are good theoretical reasons for integrated governance, but there is variable alignment of DQM, IG and health system objectives across the health enterprise. Ethical constraints exist that require health information ecosystems to process data in ways that are aligned with improving health and system efficiency and ensuring patient safety. Despite an increasingly 'big-data' environment, DQM and IG in health services are still fragmented across the data production cycle. We extend current work on DQM and IG with a theoretical framework for integrated IG across the data cycle. The dimensions of this theory-based framework would require testing with qualitative and quantitative studies to examine the applicability and utility, along with an evaluation of its impact on data quality across the health enterprise.

Theoretical repeatability assessment without repetitive measurements in gradient high-performance liquid chromatography.

Science.gov (United States)

Kotani, Akira; Tsutsumi, Risa; Shoji, Asaki; Hayashi, Yuzuru; Kusu, Fumiyo; Yamamoto, Kazuhiro; Hakamata, Hideki

2016-07-08

This paper puts forward a time and material-saving method for evaluating the repeatability of area measurements in gradient HPLC with UV detection (HPLC-UV), based on the function of mutual information (FUMI) theory which can theoretically provide the measurement standard deviation (SD) and detection limits through the stochastic properties of baseline noise with no recourse to repetitive measurements of real samples. The chromatographic determination of terbinafine hydrochloride and enalapril maleate is taken as an example. The best choice of the number of noise data points, inevitable for the theoretical evaluation, is shown to be 512 data points (10.24s at 50 point/s sampling rate of an A/D converter). Coupled with the relative SD (RSD) of sample injection variability in the instrument used, the theoretical evaluation is proved to give identical values of area measurement RSDs to those estimated by the usual repetitive method (n=6) over a wide concentration range of the analytes within the 95% confidence intervals of the latter RSD. The FUMI theory is not a statistical one, but the "statistical" reliability of its SD estimates (n=1) is observed to be as high as that attained by thirty-one measurements of the same samples (n=31). Copyright © 2016 Elsevier B.V. All rights reserved.

Theoretical predictions for spatially-focused heating of magnetic nanoparticles guided by magnetic particle imaging field gradients

Energy Technology Data Exchange (ETDEWEB)

Dhavalikar, Rohan [Department of Chemical Engineering, University of Florida, 1030 Center Drive, Gainesville, FL 32611 (United States); Rinaldi, Carlos, E-mail: carlos.rinaldi@bme.ufl.edu [Department of Chemical Engineering, University of Florida, 1030 Center Drive, Gainesville, FL 32611 (United States); J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, 1275 Center Drive, Gainesville, FL 32611 (United States)

2016-12-01

Magnetic nanoparticles in alternating magnetic fields (AMFs) transfer some of the field's energy to their surroundings in the form of heat, a property that has attracted significant attention for use in cancer treatment through hyperthermia and in developing magnetic drug carriers that can be actuated to release their cargo externally using magnetic fields. To date, most work in this field has focused on the use of AMFs that actuate heat release by nanoparticles over large regions, without the ability to select specific nanoparticle-loaded regions for heating while leaving other nanoparticle-loaded regions unaffected. In parallel, magnetic particle imaging (MPI) has emerged as a promising approach to image the distribution of magnetic nanoparticle tracers in vivo, with sub-millimeter spatial resolution. The underlying principle in MPI is the application of a selection magnetic field gradient, which defines a small region of low bias field, superimposed with an AMF (of lower frequency and amplitude than those normally used to actuate heating by the nanoparticles) to obtain a signal which is proportional to the concentration of particles in the region of low bias field. Here we extend previous models for estimating the energy dissipation rates of magnetic nanoparticles in uniform AMFs to provide theoretical predictions of how the selection magnetic field gradient used in MPI can be used to selectively actuate heating by magnetic nanoparticles in the low bias field region of the selection magnetic field gradient. Theoretical predictions are given for the spatial decay in energy dissipation rate under magnetic field gradients representative of those that can be achieved with current MPI technology. These results underscore the potential of combining MPI and higher amplitude/frequency actuation AMFs to achieve selective magnetic fluid hyperthermia (MFH) guided by MPI. - Highlights: • SAR predictions based on a field-dependent magnetization relaxation model. �

ENTREPRENEURIAL LEADERSHIP: A THEORETICAL FRAMEWORK

Directory of Open Access Journals (Sweden)

Yusuf ESMER

2017-12-01

Full Text Available Today, having just leadership or entrepreneurship qualities by business managers is not enough for success of enterprises. Managers need to have both leadership and entrepreneurship qualities in order to be successful. At this point, the concept of entrepreneurial leadership emerges. Entrepreneurial leadership is a new and modern type of leadership that is a combination of leadership qualities and spirit of entrepreneurship. In addition, entrepreneurial leadership is creating new products, new processes and expansion opportunities in existing businesses, working in social institutions and dealing with ignored social issues, participating in social and political movements, contributing to the change of current services and policies implemented by civil society organizations and governments. In recent times, entrepreneurial leadership has become a new phenomenon in business management that needs to be discussed. In this regard, in this study, the importance of entrepreneurial leadership is emphasized by examining the concept of entrepreneurial leadership within a theoretical framework.

Species richness of motile cryptofauna across a gradient of reef framework erosion

Science.gov (United States)

Enochs, I. C.; Manzello, D. P.

2012-09-01

Coral reef ecosystems contain exceptionally high concentrations of marine biodiversity, potentially encompassing millions of species. Similar to tropical rainforests and their insects, the majority of reef animal species are small and cryptic, living in the cracks and crevices of structural taxa (trees and corals). Although the cryptofauna make up the majority of a reef's metazoan biodiversity, we know little about their basic ecology. We sampled motile cryptofaunal communities from both live corals and dead carbonate reef framework across a gradient of increasing erosion on a reef in Pacific Panamá. A total of 289 Operational Taxonomic Units (OTUs) from six phyla were identified. We used species-accumulation models fitted to individual- and sample-based rarefaction curves, as well as seven nonparametric richness estimators to estimate species richness among the different framework types. All procedures predicted the same trends in species richness across the differing framework types. Estimated species richness was higher in dead framework (261-370 OTUs) than in live coral substrates (112-219 OTUs). Surprisingly, richness increased as framework structure was eroded: coral rubble contained the greatest number of species (227-320 OTUs) and the lowest estimated richness of 47-115 OTUs was found in the zone where the reef framework had the greatest vertical relief. This contradicts the paradigm that abundant live coral indicates the apex of reef diversity.

The functional-cognitive meta-theoretical framework: Reflections, possible clarifications and how to move forward.

Science.gov (United States)

Barnes-Holmes, Dermot; Hussey, Ian

2016-02-01

The functional-cognitive meta-theoretical framework has been offered as a conceptual basis for facilitating greater communication and cooperation between the functional/behavioural and cognitive traditions within psychology, thus leading to benefits for both scientific communities. The current article is written from the perspective of two functional researchers, who are also proponents of the functional-cognitive framework, and attended the "Building Bridges between the Functional and Cognitive Traditions" meeting at Ghent University in the summer of 2014. The article commences with a brief summary of the functional approach to theory, followed by our reflections upon the functional-cognitive framework in light of that meeting. In doing so, we offer three ways in which the framework could be clarified: (a) effective communication between the two traditions is likely to be found at the level of behavioural observations rather than effects or theory, (b) not all behavioural observations will be deemed to be of mutual interest to both traditions, and (c) observations of mutual interest will be those that serve to elaborate and extend existing theorising in the functional and/or cognitive traditions. The article concludes with a summary of what we perceive to be the strengths and weaknesses of the framework, and a suggestion that there is a need to determine if the framework is meta-theoretical or is in fact a third theoretical approach to doing psychological science. © 2015 International Union of Psychological Science.

A Unified Theoretical Framework for Cognitive Sequencing.

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Savalia, Tejas; Shukla, Anuj; Bapi, Raju S

2016-01-01

The capacity to sequence information is central to human performance. Sequencing ability forms the foundation stone for higher order cognition related to language and goal-directed planning. Information related to the order of items, their timing, chunking and hierarchical organization are important aspects in sequencing. Past research on sequencing has emphasized two distinct and independent dichotomies: implicit vs. explicit and goal-directed vs. habits. We propose a theoretical framework unifying these two streams. Our proposal relies on brain's ability to implicitly extract statistical regularities from the stream of stimuli and with attentional engagement organizing sequences explicitly and hierarchically. Similarly, sequences that need to be assembled purposively to accomplish a goal require engagement of attentional processes. With repetition, these goal-directed plans become habits with concomitant disengagement of attention. Thus, attention and awareness play a crucial role in the implicit-to-explicit transition as well as in how goal-directed plans become automatic habits. Cortico-subcortical loops basal ganglia-frontal cortex and hippocampus-frontal cortex loops mediate the transition process. We show how the computational principles of model-free and model-based learning paradigms, along with a pivotal role for attention and awareness, offer a unifying framework for these two dichotomies. Based on this framework, we make testable predictions related to the potential influence of response-to-stimulus interval (RSI) on developing awareness in implicit learning tasks.

A Unified Theoretical Framework for Cognitive Sequencing

Directory of Open Access Journals (Sweden)

Tejas Savalia

2016-11-01

Full Text Available The capacity to sequence information is central to human performance. Sequencing ability forms the foundation stone for higher order cognition related to language and goal-directed planning. Information related to the order of items, their timing, chunking and hierarchical organization are important aspects in sequencing. Past research on sequencing has emphasized two distinct and independent dichotomies: implicit versus explicit and goal-directed versus habits. We propose a theoretical framework unifying these two streams. Our proposal relies on brain's ability to implicitly extract statistical regularities from the stream of stimuli and with attentional engagement organizing sequences explicitly and hierarchically. Similarly, sequences that need to be assembled purposively to accomplish a goal require engagement of attentional processes. With repetition, these goal-directed plans become habits with concomitant disengagement of attention. Thus attention and awareness play a crucial role in the implicit-to-explicit transition as well as in how goal-directed plans become automatic habits. Cortico-subcortical loops ─ basal ganglia-frontal cortex and hippocampus-frontal cortex loops ─ mediate the transition process. We show how the computational principles of model-free and model-based learning paradigms, along with a pivotal role for attention and awareness, offer a unifying framework for these two dichotomies. Based on this framework, we make testable predictions related to the potential influence of response-to-stimulus interval (RSI on developing awareness in implicit learning tasks.

Revisioning Theoretical Framework of Electronic Performance Support Systems (EPSS within the Software Application Examples

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Dr. Servet BAYRAM,

2004-04-01

Full Text Available Revisioning Theoretical Framework of Electronic Performance Support Systems (EPSS within the Software Application Examples Assoc. Prof. Dr. Servet BAYRAM Computer Education & Instructional Technologies Marmara University , TURKEY ABSTRACT EPSS provides electronic support to learners in achieving a performance objective; a feature which makes it universally and consistently available on demand any time, any place, regardless of situation, without unnecessary intermediaries involved in the process. The aim of this review is to develop a set of theoretical construct that provide descriptive power for explanation of EPSS and its roots and features within the software application examples (i.e., Microsoft SharePoint Server”v2.0” Beta 2, IBM Lotus Notes 6 & Domino 6, Oracle 9i Collaboration Suite, and Mac OS X v10.2. From the educational and training point of view, the paper visualizes a pentagon model for the interrelated domains of the theoretical framework of EPSS. These domains are: learning theories, information processing theories, developmental theories, instructional theories, and acceptance theories. This descriptive framework explains a set of descriptions as to which outcomes occur under given theoretical conditions for a given EPSS model within software examples. It summarizes some of the theoretical concepts supporting to the EPSS’ related features and explains how such concepts sharing same features with the example software programs in education and job training.

Towards Culturally Relevant Classroom Science: A Theoretical Framework Focusing on Traditional Plant Healing

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Mpofu, Vongai; Otulaja, Femi S.; Mushayikwa, Emmanuel

2014-01-01

A theoretical framework is an important component of a research study. It grounds the study and guides the methodological design. It also forms a reference point for the interpretation of the research findings. This paper conceptually examines the process of constructing a multi-focal theoretical lens for guiding studies that aim to accommodate…

An integrated organisation-wide data quality management and information governance framework: theoretical underpinnings

Directory of Open Access Journals (Sweden)

Siaw-Teng Liaw

2014-10-01

Full Text Available Introduction Increasing investment in eHealth aims to improve cost effectiveness and safety of care. Data extraction and aggregation can create new data products to improve professional practice and provide feedback to improve the quality of source data. A previous systematic review concluded that locally relevant clinical indicators and use of clinical record systems could support clinical governance. We aimed to extend and update the review with a theoretical framework.Methods We searched PubMed, Medline, Web of Science, ABI Inform (Proquest and Business Source Premier (EBSCO using the terms curation, information ecosystem, data quality management (DQM, data governance, information governance (IG and data stewardship. We focused on and analysed the scope of DQM and IG processes, theoretical frameworks, and determinants of the processing, quality assurance, presentation and sharing of data across the enterprise.Findings There are good theoretical reasons for integrated governance, but there is variable alignment of DQM, IG and health system objectives across the health enterprise. Ethical constraints exist that require health information ecosystems to process data in ways that are aligned with improving health and system efficiency and ensuring patient safety. Despite an increasingly ‘big-data’ environment, DQM and IG in health services are still fragmented across the data production cycle. We extend current work on DQM and IG with a theoretical framework for integrated IG across the data cycle.Conclusions The dimensions of this theory-based framework would require testing with qualitative and quantitative studies to examine the applicability and utility, along with an evaluation of its impact on data quality across the health enterprise.

An integrative theoretical framework of acculturation and salutogenesis.

Science.gov (United States)

Riedel, Jeannette; Wiesmann, Ulrich; Hannich, Hans-Joachim

2011-12-01

During the last two decades, the number of international migrants worldwide has constantly risen. In this context, cross-cultural dimensions of psychological disorders receive increased attention, especially depression, anxiety and post-traumatic stress disorders among the migrant population. In this paper we propose a theoretical framework for the understanding of migrant mental health. This framework combines elements from Berry's acculturation model and Antonovsky's salutogenic theory. The former illustrates the main factors that affect an individual's adaptation in a new cultural context. The term acculturative stress denotes unresolved problems resulting from intercultural contact that cannot be overcome easily by simply adjusting or assimilating. The latter specifies the relationship between culturally associated stress and mental health more distinctive, introducing the concepts of generalized resistance resources and sense of coherence that determine mental health outcomes of migrants during acculturative stress periods. Specifically, we provide an integrative framework of acculturation and salutogenesis that helps to integrate inconsistent findings in the migrant mental health literature. The current paper focuses on the effect of resource factors for positive mental health outcomes in the migrant population and summarises some implications for future research activities.

An Expanded Theoretical Framework of Care Coordination Across Transitions in Care Settings.

Science.gov (United States)

Radwin, Laurel E; Castonguay, Denise; Keenan, Carolyn B; Hermann, Cherice

2016-01-01

For many patients, high-quality, patient-centered, and cost-effective health care requires coordination among multiple clinicians and settings. Ensuring optimal care coordination requires a clear understanding of how clinician activities and continuity during transitions affect patient-centeredness and quality outcomes. This article describes an expanded theoretical framework to better understand care coordination. The framework provides clear articulation of concepts. Examples are provided of ways to measure the concepts.

Field-widened Michelson interferometer for spectral discrimination in high-spectral-resolution lidar: theoretical framework.

Science.gov (United States)

Cheng, Zhongtao; Liu, Dong; Luo, Jing; Yang, Yongying; Zhou, Yudi; Zhang, Yupeng; Duan, Lulin; Su, Lin; Yang, Liming; Shen, Yibing; Wang, Kaiwei; Bai, Jian

2015-05-04

A field-widened Michelson interferometer (FWMI) is developed to act as the spectral discriminator in high-spectral-resolution lidar (HSRL). This realization is motivated by the wide-angle Michelson interferometer (WAMI) which has been used broadly in the atmospheric wind and temperature detection. This paper describes an independent theoretical framework about the application of the FWMI in HSRL for the first time. In the framework, the operation principles and application requirements of the FWMI are discussed in comparison with that of the WAMI. Theoretical foundations for designing this type of interferometer are introduced based on these comparisons. Moreover, a general performance estimation model for the FWMI is established, which can provide common guidelines for the performance budget and evaluation of the FWMI in the both design and operation stages. Examples incorporating many practical imperfections or conditions that may degrade the performance of the FWMI are given to illustrate the implementation of the modeling. This theoretical framework presents a complete and powerful tool for solving most of theoretical or engineering problems encountered in the FWMI application, including the designing, parameter calibration, prior performance budget, posterior performance estimation, and so on. It will be a valuable contribution to the lidar community to develop a new generation of HSRLs based on the FWMI spectroscopic filter.

Cusps in K→3π decays: A theoretical framework

International Nuclear Information System (INIS)

Gasser, Juerg; Kubis, Bastian; Rusetsky, Akaki

2011-01-01

Based on the analysis of 6.031x10 7 K ± →π 0 π 0 π ± decays, the NA48/2 Collaboration has recently determined the S-wave ππ scattering lengths a 0 -a 2 with high precision. In addition, the scattering length a 2 has been independently measured, although less precisely so. The present article discusses in detail one of the theoretical frameworks used in the data analysis.

Nursing management of sensory overload in psychiatry – Theoretical densification and modification of the framework model

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Scheydt, Stefan; Needham, Ian; Behrens, Johann

2017-01-01

Background: Within the scope of the research project on the subjects of sensory overload and stimulus regulation, a theoretical framework model of the nursing care of patients with sensory overload in psychiatry was developed. In a second step, this theoretical model should now be theoretically compressed and, if necessary, modified. Aim: Empirical verification as well as modification, enhancement and theoretical densification of the framework model of nursing care of patients with sensory overload in psychiatry. Method: Analysis of 8 expert interviews by summarizing and structuring content analysis methods based on Meuser and Nagel (2009) as well as Mayring (2010). Results: The developed framework model (Scheydt et al., 2016b) could be empirically verified, theoretically densificated and extended by one category (perception modulation). Thus, four categories of nursing care of patients with sensory overload can be described in inpatient psychiatry: removal from stimuli, modulation of environmental factors, perceptual modulation as well as help somebody to help him- or herself / coping support. Conclusions: Based on the methodological approach, a relatively well-saturated, credible conceptualization of a theoretical model for the description of the nursing care of patients with sensory overload in stationary psychiatry could be worked out. In further steps, these measures have to be further developed, implemented and evaluated regarding to their efficacy.

A general theoretical framework for decoherence in open and closed systems

International Nuclear Information System (INIS)

Castagnino, Mario; Fortin, Sebastian; Laura, Roberto; Lombardi, Olimpia

2008-01-01

A general theoretical framework for decoherence is proposed, which encompasses formalisms originally devised to deal just with open or closed systems. The conditions for decoherence are clearly stated and the relaxation and decoherence times are compared. Finally, the spin-bath model is developed in detail from the new perspective

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

Science.gov (United States)

Ornek, Funda

2008-01-01

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

Enhancing early detection of exotic pests in agricultural and forest ecosystems using an urban-gradient framework.

Science.gov (United States)

Colunga-Garcia, Manuel; Magarey, Roger A; Haack, Robert A; Gage, Stuart H; Qi, Jiaquo

2010-03-01

Urban areas are hubs of international transport and therefore are major gateways for exotic pests. Applying an urban gradient to analyze this pathway could provide insight into the ecological processes involved in human-mediated invasions. We defined an urban gradient for agricultural and forest ecosystems in the contiguous United States to (1) assess whether ecosystems nearer more urbanized areas were at greater risk of invasion, and (2) apply this knowledge to enhance early detection of exotic pests. We defined the gradient using the tonnage of imported products in adjacent urban areas and their distance to nearby agricultural or forest land. County-level detection reports for 39 exotic agricultural and forest pests of major economic importance were used to characterize invasions along the gradient. We found that counties with more exotic pests were nearer the urban end of the gradient. Assuming that the exotic species we analyzed represent typical invaders, then early detection efforts directed at 21-26% of U.S. agricultural and forest land would likely be able to detect 70% of invaded counties and 90% of the selected species. Applying an urban-gradient framework to current monitoring strategies should enhance early detection efforts of exotic pests, facilitating optimization in allocating resources to areas at greater risk of future invasions.

Gaming the System: Video Games as a Theoretical Framework for Instructional Design

OpenAIRE

Beatty, Ian D.

2014-01-01

In order to facilitate analyzing video games as learning systems and instructional designs as games, we present a theoretical framework that integrates ideas from a broad range of literature. The framework describes games in terms of four layers, all sharing similar structural elements and dynamics: a micro-level game focused on immediate problem-solving and skill development, a macro-level game focused on the experience of the game world and story and identity development, and two meta-level...

Memory and the Self in Autism: A Review and Theoretical Framework

Science.gov (United States)

Lind, Sophie E.

2010-01-01

This article reviews research on (a) autobiographical episodic and semantic memory, (b) the self-reference effect, (c) memory for the actions of self versus other (the self-enactment effect), and (d) non-autobiographical episodic memory in autism spectrum disorder (ASD), and provides a theoretical framework to account for the bidirectional…

Theoretical Framework of Advanced Training in the Field of Conflict Management in Organization

Directory of Open Access Journals (Sweden)

Kilmashkina T.N.

2018-01-01

Full Text Available In this paper, we consider the theoretical framework for creating an advanced training course for professionals working in various organizations whose functional duties include activities aimed at managing conflict situations occurring within the organization. The article also considers such problem concepts as: essence and causes of conflicts, types of conflicts in the organization; organizational, psychological, sociological and cultural ways of managing conflicts in the organization. The proposed theoretical model of advanced professional training is constructed within the framework of the competence approach which, in this case, is based on the notion that a participant in the program should master a certain set of special competencies that include knowledge, skills and abilities necessary for the effective process management of various conflict situations.

Assessing Professionalism: A Theoretical Framework for Defining Clinical Rotation Assessment Criteria.

Science.gov (United States)

Armitage-Chan, Elizabeth

Although widely accepted as an important graduate competence, professionalism is a challenging outcome to define and assess. Clinical rotations provide an excellent opportunity to develop student professionalism through the use of experiential learning and effective feedback, but without appropriate theoretical frameworks, clinical teachers may find it difficult to identify appropriate learning outcomes. The adage "I know it when I see it" is unhelpful in providing feedback and guidance for student improvement, and criteria that are more specifically defined would help students direct their own development. This study sought first to identify how clinical faculty in one institution currently assess professionalism, using retrospective analysis of material obtained in undergraduate teaching and faculty development sessions. Subsequently, a faculty workshop was held in which a round-table type discussion sought to develop these ideas and identify how professionalism assessment could be improved. The output of this session was a theoretical framework for teaching and assessing professionalism, providing example assessment criteria and ideas for clinical teaching. This includes categories such as client and colleague interaction, respect and trust, recognition of limitations, and understanding of different professional identities. Each category includes detailed descriptions of the knowledge, skills, and behaviors expected of students in these areas. The criteria were determined by engaging faculty in the development of the framework, and therefore they should represent a focused development of criteria already used to assess professionalism, and not a novel and unfamiliar set of assessment guidelines. The faculty-led nature of this framework is expected to facilitate implementation in clinical teaching.

Experiences of using the Theoretical Domains Framework across diverse clinical environments: a qualitative study

Science.gov (United States)

Phillips, Cameron J; Marshall, Andrea P; Chaves, Nadia J; Jankelowitz, Stacey K; Lin, Ivan B; Loy, Clement T; Rees, Gwyneth; Sakzewski, Leanne; Thomas, Susie; To, The-Phung; Wilkinson, Shelley A; Michie, Susan

2015-01-01

Background The Theoretical Domains Framework (TDF) is an integrative framework developed from a synthesis of psychological theories as a vehicle to help apply theoretical approaches to interventions aimed at behavior change. Purpose This study explores experiences of TDF use by professionals from multiple disciplines across diverse clinical settings. Methods Mixed methods were used to examine experiences, attitudes, and perspectives of health professionals in using the TDF in health care implementation projects. Individual interviews were conducted with ten health care professionals from six disciplines who used the TDF in implementation projects. Deductive content and thematic analysis were used. Results Three main themes and associated subthemes were identified including: 1) reasons for use of the TDF (increased confidence, broader perspective, and theoretical underpinnings); 2) challenges using the TDF (time and resources, operationalization of the TDF) and; 3) future use of the TDF. Conclusion The TDF provided a useful, flexible framework for a diverse group of health professionals working across different clinical settings for the assessment of barriers and targeting resources to influence behavior change for implementation projects. The development of practical tools and training or support is likely to aid the utility of TDF. PMID:25834455

Experiences of using the Theoretical Domains Framework across diverse clinical environments: a qualitative study.

Science.gov (United States)

Phillips, Cameron J; Marshall, Andrea P; Chaves, Nadia J; Jankelowitz, Stacey K; Lin, Ivan B; Loy, Clement T; Rees, Gwyneth; Sakzewski, Leanne; Thomas, Susie; To, The-Phung; Wilkinson, Shelley A; Michie, Susan

2015-01-01

The Theoretical Domains Framework (TDF) is an integrative framework developed from a synthesis of psychological theories as a vehicle to help apply theoretical approaches to interventions aimed at behavior change. This study explores experiences of TDF use by professionals from multiple disciplines across diverse clinical settings. Mixed methods were used to examine experiences, attitudes, and perspectives of health professionals in using the TDF in health care implementation projects. Individual interviews were conducted with ten health care professionals from six disciplines who used the TDF in implementation projects. Deductive content and thematic analysis were used. Three main themes and associated subthemes were identified including: 1) reasons for use of the TDF (increased confidence, broader perspective, and theoretical underpinnings); 2) challenges using the TDF (time and resources, operationalization of the TDF) and; 3) future use of the TDF. The TDF provided a useful, flexible framework for a diverse group of health professionals working across different clinical settings for the assessment of barriers and targeting resources to influence behavior change for implementation projects. The development of practical tools and training or support is likely to aid the utility of TDF.

Proverbs as Theoretical Frameworks for Lifelong Learning in Indigenous African Education

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Avoseh, Mejai B. M.

2013-01-01

Every aspect of a community's life and values in indigenous Africa provide the theoretical framework for education. The holistic worldview of the traditional system places a strong emphasis on the centrality of the human element and orature in the symmetrical relationship between life and learning. This article focuses on proverbs and the words…

[A framework for evaluating ethical issues of public health initiatives: practical aspects and theoretical implications].

Science.gov (United States)

Petrini, Carlo

2015-01-01

The "Framework for the Ethical Conduct of Public Health Initiatives", developed by Public Health Ontario, is a practical guide for assessing the ethical implications of evidence-generating public health initiatives, whether research or non-research activities, involving people, their biological materials or their personal information. The Framework is useful not only to those responsible for determining the ethical acceptability of an initiative, but also to investigators planning new public health initiatives. It is informed by a theoretical approach that draws on widely shared bioethical principles. Two considerations emerge from both the theoretical framework and its practical application: the line between practice and research is often blurred; public health ethics and biomedical research ethics are based on the same common heritage of values.

Upping the "Anti-": The Value of an Anti-Racist Theoretical Framework in Music Education

Science.gov (United States)

Hess, Juliet

2015-01-01

In a time that some have argued is "postracial" following the election and reelection of Barack Obama (see Wise 2010, for discussion), this paper argues that antiracism is a crucial theoretical framework for music education. I explore three areas of music education, in which such a framework can push toward change. The first area speaks…

Modeling chemical gradients in sediments under losing and gaining flow conditions: The GRADIENT code

Science.gov (United States)

Boano, Fulvio; De Falco, Natalie; Arnon, Shai

2018-02-01

Interfaces between sediments and water bodies often represent biochemical hotspots for nutrient reactions and are characterized by steep concentration gradients of different reactive solutes. Vertical profiles of these concentrations are routinely collected to obtain information on nutrient dynamics, and simple codes have been developed to analyze these profiles and determine the magnitude and distribution of reaction rates within sediments. However, existing publicly available codes do not consider the potential contribution of water flow in the sediments to nutrient transport, and their applications to field sites with significant water-borne nutrient fluxes may lead to large errors in the estimated reaction rates. To fill this gap, the present work presents GRADIENT, a novel algorithm to evaluate distributions of reaction rates from observed concentration profiles. GRADIENT is a Matlab code that extends a previously published framework to include the role of nutrient advection, and provides robust estimates of reaction rates in sediments with significant water flow. This work discusses the theoretical basis of the method and shows its performance by comparing the results to a series of synthetic data and to laboratory experiments. The results clearly show that in systems with losing or gaining fluxes, the inclusion of such fluxes is critical for estimating local and overall reaction rates in sediments.

Praxis and reflexivity for interprofessional education: towards an inclusive theoretical framework for learning.

Science.gov (United States)

Hutchings, Maggie; Scammell, Janet; Quinney, Anne

2013-09-01

While there is growing evidence of theoretical perspectives adopted in interprofessional education, learning theories tend to foreground the individual, focusing on psycho-social aspects of individual differences and professional identity to the detriment of considering social-structural factors at work in social practices. Conversely socially situated practice is criticised for being context-specific, making it difficult to draw generalisable conclusions for improving interprofessional education. This article builds on a theoretical framework derived from earlier research, drawing on the dynamics of Dewey's experiential learning theory and Archer's critical realist social theory, to make a case for a meta-theoretical framework enabling social-constructivist and situated learning theories to be interlinked and integrated through praxis and reflexivity. Our current analysis is grounded in an interprofessional curriculum initiative mediated by a virtual community peopled by health and social care users. Student perceptions, captured through quantitative and qualitative data, suggest three major disruptive themes, creating opportunities for congruence and disjuncture and generating a model of zones of interlinked praxis associated with professional differences and identity, pedagogic strategies and technology-mediated approaches. This model contributes to a framework for understanding the complexity of interprofessional learning and offers bridges between individual and structural factors for engaging with the enablements and constraints at work in communities of practice and networks for interprofessional education.

The Community-First Land-Centred Theoretical Framework: Bringing a "Good Mind" to Indigenous Education Research?

Science.gov (United States)

Styres, Sandra D.; Zinga, Dawn M.

2013-01-01

This article introduces an emergent research theoretical framework, the community-first Land-centred research framework. Carefully examining the literature within Indigenous educational research, we noted the limited approaches for engaging in culturally aligned and relevant research within Indigenous communities. The community-first Land-centred…

POSITIVE LEADERSHIP MODELS: THEORETICAL FRAMEWORK AND RESEARCH

Directory of Open Access Journals (Sweden)

Javier Blanch, Francisco Gil

2016-09-01

Full Text Available The objective of this article is twofold; firstly, we establish the theoretical boundaries of positive leadership and the reasons for its emergence. It is related to the new paradigm of positive psychology that has recently been shaping the scope of organizational knowledge. This conceptual framework has triggered the development of the various forms of positive leadership (i.e. transformational, servant, spiritual, authentic, and positive. Although the construct does not seem univocally defined, these different types of leadership overlap and share a significant affinity. Secondly, we review the empirical evidence that shows the impact of positive leadership in organizations and we highlight the positive relationship between these forms of leadership and key positive organizational variables. Lastly, we analyse future research areas in order to further develop this concept.

System Theoretic Frameworks for Mitigating Risk Complexity in the Nuclear Fuel Cycle

Energy Technology Data Exchange (ETDEWEB)

Williams, Adam David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Mohagheghi, Amir H. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Cohn, Brian [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Osborn, Douglas M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jones, Katherine A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); DeMenno, Mercy [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kalinina, Elena Arkadievna [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Thomas, Maikael A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Parks, Ethan Rutledge [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Parks, Mancel Jordan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jeantete, Brian A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-09-01

In response to the expansion of nuclear fuel cycle (NFC) activities -- and the associated suite of risks -- around the world, this project evaluated systems-based solutions for managing such risk complexity in multimodal and multi-jurisdictional international spent nuclear fuel (SNF) transportation. By better understanding systemic risks in SNF transportation, developing SNF transportation risk assessment frameworks, and evaluating these systems-based risk assessment frameworks, this research illustrated interdependency between safety, security, and safeguards risks is inherent in NFC activities and can go unidentified when each "S" is independently evaluated. Two novel system-theoretic analysis techniques -- dynamic probabilistic risk assessment (DPRA) and system-theoretic process analysis (STPA) -- provide integrated "3S" analysis to address these interdependencies and the research results suggest a need -- and provide a way -- to reprioritize United States engagement efforts to reduce global nuclear risks. Lastly, this research identifies areas where Sandia National Laboratories can spearhead technical advances to reduce global nuclear dangers.

Mapping For Literature Conceptual And Theoretical Framework And Methodology Case Of Hot Deep Mining Ventilation Engineering Evaluation And Design

Directory of Open Access Journals (Sweden)

Peter M. Lukonde

2017-09-01

Full Text Available The paper reports the layout of a mapping process for literature theoretical and conceptual framework and methodology for mining ventilation engineering evaluation design and methodology for a hot deep mine. The purpose of mine ventilation is to provide suitable environmental conditions in working places that promote comfort and efficiency as well as the safety and health of underground personnel. The objectives addressed in this paper include a evaluation of a current mine ventilation system for a hot deep-level mine taking into account the existing ventilation system infrastructure for building of a mine ventilation baseline parametric database for subsequent end of life mine ventilation design and b design of the extension end of mine life ventilation system taking into account increased production high geothermic gradient and subsequent increase in depth of mining. The methodology used in evaluating an existing underground mine ventilation system and designing the extension end of mine life ventilation system employed three stages i Literature mapping to identify authors titles and technical papers at global regional and nationaldistrict scales relevant to the research ii Conceptual and theoretical framework mapping to extract a kernel or core of concepts hypotheses and theories from the literature map to drive the formation of methods of implementation and iii Methodology and implementation mapping to direct and control the processes of data collection analysis and interpretation. A sample case study of a deep-level underground mine has been used in this paper to provide examples of data collection data analysis and interpretation key findings and results discussion and what is new conclusions and recommendations when the proposed mapping process is employed.

A theoretical framework for holistic hospital management in the Japanese healthcare context.

Science.gov (United States)

Liu, Hu-Chen

2013-11-01

This paper develops a conceptual framework for performance measurement as a pilot study on holistic hospital management in the Japanese healthcare context. We primarily used two data sources as well as expert statements obtained through interviews: a systematic review of literature and a questionnaire survey to healthcare experts. The systematic survey searched PubMed and PubMed Central, and 24 relevant papers were elicited. The expert questionnaire asked respondents to rate the degree of "usefulness" for each of 66 indicators on a three-point scale. Applying the theoretical framework, a minimum set of performance indicators was selected for holistic hospital management, which well fit the healthcare context in Japan. This indicator set comprised 35 individual indicators and several factors measured through questionnaire surveys. The indicators were confirmed by expert judgments from viewpoints of face, content and construct validities as well as their usefulness. A theoretical framework of performance measurement was established from primary healthcare stakeholders' perspectives. Performance indicators were largely divided into healthcare outcomes and performance shaping factors. Indicators in the former category may be applied for the detection of operational problems, while their latent causes can be effectively addressed by the latter category in terms of process, structure and culture/climate within the organization. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

The conceptual basis for interprofessional collaboration: core concepts and theoretical frameworks.

Science.gov (United States)

D'Amour, Danielle; Ferrada-Videla, Marcela; San Martin Rodriguez, Leticia; Beaulieu, Marie-Dominique

2005-05-01

Interprofessional collaboration is a key factor in initiatives designed to increase the effectiveness of health services currently offered to the public. It is important that the concept of collaboration be well understood, because although the increasingly complex health problems faced by health professionals are creating more interdependencies among them, we still have limited knowledge of the complexity of interprofessional relationships. The goal of this literature review was to identify conceptual frameworks that could improve our understanding of this important aspect of health organizations. To this end, we have identified and taken into consideration: (A) the various definitions proposed in the literature and the various concepts associated with collaboration, and (B) the various theoretical frameworks of collaboration. Our results demonstrate that: (1) the concept of collaboration is commonly defined through five underlying concepts: sharing, partnership, power, interdependency and process; (2) the most complete models of collaboration seem to be those based on a strong theoretical background, either in organizational theory or in organizational sociology and on empirical data; (3) there is a significant amount of diversity in the way the various authors conceptualized collaboration and in the factors influencing collaboration; (4) these frameworks do not establish clear links between the elements in the models and the outputs; and (5) the literature does not provide a serious attempt to determine how patients could be integrated into the health care team, despite the fact that patients are recognized as the ultimate justification for providing collaborative care.

The Roy Adaptation Model: A Theoretical Framework for Nurses Providing Care to Individuals With Anorexia Nervosa.

Science.gov (United States)

Jennings, Karen M

Using a nursing theoretical framework to understand, elucidate, and propose nursing research is fundamental to knowledge development. This article presents the Roy Adaptation Model as a theoretical framework to better understand individuals with anorexia nervosa during acute treatment, and the role of nursing assessments and interventions in the promotion of weight restoration. Nursing assessments and interventions situated within the Roy Adaptation Model take into consideration how weight restoration does not occur in isolation but rather reflects an adaptive process within external and internal environments, and has the potential for more holistic care.

The Problem With the Phrase Women and Minorities: Intersectionality—an Important Theoretical Framework for Public Health

Science.gov (United States)

2012-01-01

Intersectionality is a theoretical framework that posits that multiple social categories (e.g., race, ethnicity, gender, sexual orientation, socioeconomic status) intersect at the micro level of individual experience to reflect multiple interlocking systems of privilege and oppression at the macro, social-structural level (e.g., racism, sexism, heterosexism). Public health’s commitment to social justice makes it a natural fit with intersectionality’s focus on multiple historically oppressed populations. Yet despite a plethora of research focused on these populations, public health studies that reflect intersectionality in their theoretical frameworks, designs, analyses, or interpretations are rare. Accordingly, I describe the history and central tenets of intersectionality, address some theoretical and methodological challenges, and highlight the benefits of intersectionality for public health theory, research, and policy. PMID:22594719

The problem with the phrase women and minorities: intersectionality-an important theoretical framework for public health.

Science.gov (United States)

Bowleg, Lisa

2012-07-01

Intersectionality is a theoretical framework that posits that multiple social categories (e.g., race, ethnicity, gender, sexual orientation, socioeconomic status) intersect at the micro level of individual experience to reflect multiple interlocking systems of privilege and oppression at the macro, social-structural level (e.g., racism, sexism, heterosexism). Public health's commitment to social justice makes it a natural fit with intersectionality's focus on multiple historically oppressed populations. Yet despite a plethora of research focused on these populations, public health studies that reflect intersectionality in their theoretical frameworks, designs, analyses, or interpretations are rare. Accordingly, I describe the history and central tenets of intersectionality, address some theoretical and methodological challenges, and highlight the benefits of intersectionality for public health theory, research, and policy.

Cusps in K{yields}3{pi} decays: A theoretical framework

Energy Technology Data Exchange (ETDEWEB)

Gasser, Juerg, E-mail: gasser@itp.unibe.ch [Albert Einstein Center for Fundamental Physics, Institute for Theoretical Physics, University of Bern, Sidlerstr. 5, CH-3012 Bern (Switzerland); Kubis, Bastian, E-mail: kubis@hiskp.uni-bonn.de [Helmholtz-Institut fuer Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Universitaet Bonn, Nussallee 14-16, D-53115 Bonn (Germany); Rusetsky, Akaki, E-mail: rusetsky@hiskp.uni-bonn.de [Helmholtz-Institut fuer Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Universitaet Bonn, Nussallee 14-16, D-53115 Bonn (Germany)

2011-09-01

Based on the analysis of 6.031x10{sup 7}K{sup {+-}{yields}{pi}0{pi}0{pi}{+-} }decays, the NA48/2 Collaboration has recently determined the S-wave {pi}{pi} scattering lengths a{sub 0}-a{sub 2} with high precision. In addition, the scattering length a{sub 2} has been independently measured, although less precisely so. The present article discusses in detail one of the theoretical frameworks used in the data analysis.

Developing and Testing a Theoretical Framework for Computer-Mediated Transparency of Local Governments

NARCIS (Netherlands)

Grimmelikhuijsen, S.G.; Welch, E.W.

2012-01-01

This article contributes to the emerging literature on transparency by developing and empirically testing a theoretical framework that explains the determinants of local government Web site transparency. It aims to answer the following central question: What institutional factors determine the

A theoretical framework to study variations in workplace violence experienced by emergency responders

NARCIS (Netherlands)

L. van Reemst (Lisa)

2016-01-01

markdownabstractEmergency responders are often sent to the front line and are often confronted with aggression and violence in interaction with citizens. According to previous studies, some professionals experience more workplace violence than others. In this article, the theoretical framework to

A theoretical framework for a virtual diabetes self-management community intervention.

Science.gov (United States)

Vorderstrasse, Allison; Shaw, Ryan J; Blascovich, Jim; Johnson, Constance M

2014-10-01

Due to its high prevalence, chronic nature, potential complications, and self-management challenges for patients, diabetes presents significant health education and support issues. We developed and pilot-tested a virtual community for adults with type 2 diabetes to promote self-management education and provide social support. Although digital-based programs such as virtual environments can address significant barriers to reaching patients (i.e., child care, transportation, location), they must be strongly grounded in a theoretical basis to be well-developed and effective. In this article, we discuss how we synthesized behavioral and virtual environment theoretical frameworks to guide the development of SLIDES (Second Life Impacts Diabetes Education and Support). © The Author(s) 2014.

Bidirectional composition on lie groups for gradient-based image alignment.

Science.gov (United States)

Mégret, Rémi; Authesserre, Jean-Baptiste; Berthoumieu, Yannick

2010-09-01

In this paper, a new formulation based on bidirectional composition on Lie groups (BCL) for parametric gradient-based image alignment is presented. Contrary to the conventional approaches, the BCL method takes advantage of the gradients of both template and current image without combining them a priori. Based on this bidirectional formulation, two methods are proposed and their relationship with state-of-the-art gradient based approaches is fully discussed. The first one, i.e., the BCL method, relies on the compositional framework to provide the minimization of the compensated error with respect to an augmented parameter vector. The second one, the projected BCL (PBCL), corresponds to a close approximation of the BCL approach. A comparative study is carried out dealing with computational complexity, convergence rate and frequence of convergence. Numerical experiments using a conventional benchmark show the performance improvement especially for asymmetric levels of noise, which is also discussed from a theoretical point of view.

A Theoretical Framework to Study Variations in Workplace Violence Experienced by Emergency Responders

NARCIS (Netherlands)

L. van Reemst (Lisa)

2016-01-01

textabstractEmergency responders are often sent to the front line and are often confronted with aggression and violence in inter- action with citizens. According to previous studies, some professionals experience more workplace violence than others. In this article, the theoretical framework to

Combined use of the Consolidated Framework for Implementation Research (CFIR) and the Theoretical Domains Framework (TDF): a systematic review.

Science.gov (United States)

Birken, Sarah A; Powell, Byron J; Presseau, Justin; Kirk, M Alexis; Lorencatto, Fabiana; Gould, Natalie J; Shea, Christopher M; Weiner, Bryan J; Francis, Jill J; Yu, Yan; Haines, Emily; Damschroder, Laura J

2017-01-05

Over 60 implementation frameworks exist. Using multiple frameworks may help researchers to address multiple study purposes, levels, and degrees of theoretical heritage and operationalizability; however, using multiple frameworks may result in unnecessary complexity and redundancy if doing so does not address study needs. The Consolidated Framework for Implementation Research (CFIR) and the Theoretical Domains Framework (TDF) are both well-operationalized, multi-level implementation determinant frameworks derived from theory. As such, the rationale for using the frameworks in combination (i.e., CFIR + TDF) is unclear. The objective of this systematic review was to elucidate the rationale for using CFIR + TDF by (1) describing studies that have used CFIR + TDF, (2) how they used CFIR + TDF, and (2) their stated rationale for using CFIR + TDF. We undertook a systematic review to identify studies that mentioned both the CFIR and the TDF, were written in English, were peer-reviewed, and reported either a protocol or results of an empirical study in MEDLINE/PubMed, PsycInfo, Web of Science, or Google Scholar. We then abstracted data into a matrix and analyzed it qualitatively, identifying salient themes. We identified five protocols and seven completed studies that used CFIR + TDF. CFIR + TDF was applied to studies in several countries, to a range of healthcare interventions, and at multiple intervention phases; used many designs, methods, and units of analysis; and assessed a variety of outcomes. Three studies indicated that using CFIR + TDF addressed multiple study purposes. Six studies indicated that using CFIR + TDF addressed multiple conceptual levels. Four studies did not explicitly state their rationale for using CFIR + TDF. Differences in the purposes that authors of the CFIR (e.g., comprehensive set of implementation determinants) and the TDF (e.g., intervention development) propose help to justify the use of CFIR�

Finite element implementation and numerical issues of strain gradient plasticity with application to metal matrix composites

DEFF Research Database (Denmark)

Frederiksson, Per; Gudmundson, Peter; Mikkelsen, Lars Pilgaard

2009-01-01

A framework of finite element equations for strain gradient plasticity is presented. The theoretical framework requires plastic strain degrees of freedom in addition to displacements and a plane strain version is implemented into a commercial finite element code. A couple of different elements...... of quadrilateral type are examined and a few numerical issues are addressed related to these elements as well as to strain gradient plasticity theories in general. Numerical results are presented for an idealized cell model of a metal matrix composite under shear loading. It is shown that strengthening due...... to fiber size is captured but strengthening due to fiber shape is not. A few modelling aspects of this problem are discussed as well. An analytic solution is also presented which illustrates similarities to other theories....

Comparisons of theoretically predicted transport from ion temperature gradient instabilities to L-mode tokamak experiments

International Nuclear Information System (INIS)

Kotschenreuther, M.; Wong, H.V.; Lyster, P.L.; Berk, H.L.; Denton, R.; Miner, W.H.; Valanju, P.

1991-12-01

The theoretical transport from kinetic micro-instabilities driven by ion temperature gradients is a sheared slab is compared to experimentally inferred transport in L-mode tokamaks. Low noise gyrokinetic simulation techniques are used to obtain the ion thermal transport coefficient X. This X is much smaller than in experiments, and so cannot explain L-mode confinement. Previous predictions based on fluid models gave much greater X than experiments. Linear and nonlinear comparisons with the fluid model show that it greatly overestimates transport for experimental parameters. In addition, disagreements among previous analytic and simulation calculations of X in the fluid model are reconciled

Magnetoelectric Transverse Gradient Sensor with High Detection Sensitivity and Low Gradient Noise

OpenAIRE

Zhang, Mingji; Or, Siu Wing

2017-01-01

We report, theoretically and experimentally, the realization of a high detection performance in a novel magnetoelectric (ME) transverse gradient sensor based on the large ME effect and the magnetic field gradient (MFG) technique in a pair of magnetically-biased, electrically-shielded, and mechanically-enclosed ME composites having a transverse orientation and an axial separation. The output voltage of the gradient sensor is directly obtained from the transverse MFG-induced difference in ME vo...

State-of-the-Art: Research Theoretical Framework of Information Systems Implementation Research in the Health Sector in Sub-Saharan Africa

DEFF Research Database (Denmark)

Tetteh, Godwin Kofi

2014-01-01

This study is about the state-of-the-art of reference theories and theoretical framework of information systems implementation research in the health industry in the Sub-Saharan countries from a process perspective. A process – variance framework, Poole et al, (2000), Markus & Robey, (1988......) and Shaw & Jarvenpaa, (1997) is employed to examine reference theories employed in research conducted on information systems implementation in the health sector in the Sub-Saharan region and published between 2003 and 2013. Using a number of key words and searching on a number of databases, EBSCO, CSA...... the process theoretical framework to enhance our insight into successful information systems implementation in the region. It is our optimism that the process based theoretical framework will be useful for, information system practitioners and organisational managers and researchers in the health sector...

What can triple helix frameworks offer to the analysis of eco-innovation dynamics? Theoretical and methodological considerations

DEFF Research Database (Denmark)

Yang, Yan; Holgaard, Jette Egelund; Remmen, Arne

2012-01-01

stakeholder groups are interacting in this connection. Taking the triple helix as the theoretical departure point, this paper discusses the opportunities offered by these triple helix frameworks for analyzing eco-innovation dynamics from both theoretical and practical perspectives. It adds to the debate about......Bringing environmental concerns into focus of innovation processes will in several cases also expand the numbers of actors involved. Eco-innovation and triple helix are often frameworks applied to analyse how environmental concerns are integrated in the innovation processes and how different...

Understanding effects in reviews of implementation interventions using the Theoretical Domains Framework.

Science.gov (United States)

Little, Elizabeth A; Presseau, Justin; Eccles, Martin P

2015-06-17

Behavioural theory can be used to better understand the effects of behaviour change interventions targeting healthcare professional behaviour to improve quality of care. However, the explicit use of theory is rarely reported despite interventions inevitably involving at least an implicit idea of what factors to target to implement change. There is a quality of care gap in the post-fracture investigation (bone mineral density (BMD) scanning) and management (bisphosphonate prescription) of patients at risk of osteoporosis. We aimed to use the Theoretical Domains Framework (TDF) within a systematic review of interventions to improve quality of care in post-fracture investigation. Our objectives were to explore which theoretical factors the interventions in the review may have been targeting and how this might be related to the size of the effect on rates of BMD scanning and osteoporosis treatment with bisphosphonate medication. A behavioural scientist and a clinician independently coded TDF domains in intervention and control groups. Quantitative analyses explored the relationship between intervention effect size and total number of domains targeted, and as number of different domains targeted. Nine randomised controlled trials (RCTs) (10 interventions) were analysed. The five theoretical domains most frequently coded as being targeted by the interventions in the review included "memory, attention and decision processes", "knowledge", "environmental context and resources", "social influences" and "beliefs about consequences". Each intervention targeted a combination of at least four of these five domains. Analyses identified an inverse relationship between both number of times and number of different domains coded and the effect size for BMD scanning but not for bisphosphonate prescription, suggesting that the more domains the intervention targeted, the lower the observed effect size. When explicit use of theory to inform interventions is absent, it is possible to

Short communication. Economics of natural resources: in search of a unified theoretical framework

Energy Technology Data Exchange (ETDEWEB)

Romero, C.

2012-11-01

This paper proposes a unified theoretical framework for dealing with the optimum economic use of any type of natural resource. After formulating and economically interpreting the unified framework, the basic rules governing the economic exploitation of the different natural resources can be easily obtained by particularizing the different values of its basic parameters. Taking this approach, it is easy to understand what commonalities there are, in terms of economic logic, between the different types of natural resources. This considerably increases the amount of consilience and understanding about the discipline. (Author) 8 refs.

Analysing Theoretical Frameworks of Moral Education through Lakatos's Philosophy of Science

Science.gov (United States)

Han, Hyemin

2014-01-01

The structure of studies of moral education is basically interdisciplinary; it includes moral philosophy, psychology, and educational research. This article systematically analyses the structure of studies of moral educational from the vantage points of philosophy of science. Among the various theoretical frameworks in the field of philosophy of…

Utilizing the Theoretical Framework of Collective Identity to Understand Processes in Youth Programs

Science.gov (United States)

Futch, Valerie A.

2016-01-01

This article explores collective identity as a useful theoretical framework for understanding social and developmental processes that occur in youth programs. Through narrative analysis of past participant interviews (n = 21) from an after-school theater program, known as "The SOURCE", it was found that participants very clearly describe…

Very Long (> 48 hours) Shifts and Cardiovascular Strain in Firefighters: a Theoretical Framework.

Science.gov (United States)

Choi, Bongkyoo; Schnall, Peter L; Dobson, Marnie; Garcia-Rivas, Javier; Kim, Hyoungryoul; Zaldivar, Frank; Israel, Leslie; Baker, Dean

2014-03-06

Shift work and overtime have been implicated as important work-related risk factors for cardiovascular disease (CVD). Many firefighters who contractually work on a 24-hr work schedule, often do overtime (additional 24-hr shifts) which can result in working multiple, consecutive 24-hr shifts. Very little research has been conducted on firefighters at work that examines the impact of performing consecutive 24-hr shifts on cardiovascular physiology. Also, there have been no standard field methods for assessing in firefighters the cardiovascular changes that result from 24-hr shifts, what we call "cardiovascular strain". The objective of this study, as the first step toward elucidating the role of very long (> 48 hrs) shifts in the development of CVD in firefighters, is to develop and describe a theoretical framework for studying cardiovascular strain in firefighters on very long shifts (i.e., > 2 consecutive 24-hr shifts). The developed theoretical framework was built on an extensive literature review, our recently completed studies with firefighters in Southern California, e-mail and discussions with several firefighters on their experiences of consecutive shifts, and our recently conducted feasibility study in a small group of firefighters of several ambulatory cardiovascular strain biomarkers (heart rate, heart rate variability, blood pressure, salivary cortisol, and salivary C-reactive protein). The theoretical framework developed in this study will facilitate future field studies on consecutive 24-hr shifts and cardiovascular health in firefighters. Also it will increase our understanding of the mechanisms by which shift work or long work hours can affect CVD, particularly through CVD biological risk factors, and thereby inform policy about sustainable work and rest schedules for firefighters.

Preliminary Findings in the Development of a Theoretical Framework for Investigating ICT Integration in Teacher Education

Directory of Open Access Journals (Sweden)

Suthagar Narasuman

2012-06-01

Full Text Available The following report is the result of a preliminary investigation in the development of a theoretical framework for investigating ICT integration, particularly in TESL (Teaching of English as a Second Language teacher training. The study is primarily an empirical effort to develop a theoretical framework for investigating ICT integration in TESL teacher training. In identifying the predictive variables for the framework, the researchers conducted an intensive review of the literature which included a review of various models used in studies on ICT integration. The contributing variables identified in the present study were age, gender, experience, ICT proficiency, attitude, access to ICT infrastructure, support services, and exposure to ICT professional development programmes. In developing the framework, the study sought to determine the extent to which the observed variability in ICT integration could be predicted by these factors. The sample comprised 266 respondents working at the faculty or English Language Unit in various teacher training institutions across the country. The study predominantly employed quantitative methods of data collection. Interview data was used to corroborate information derived from the survey data.

LPI Optimization Framework for Target Tracking in Radar Network Architectures Using Information-Theoretic Criteria

Directory of Open Access Journals (Sweden)

Chenguang Shi

2014-01-01

Full Text Available Widely distributed radar network architectures can provide significant performance improvement for target detection and localization. For a fixed radar network, the achievable target detection performance may go beyond a predetermined threshold with full transmitted power allocation, which is extremely vulnerable in modern electronic warfare. In this paper, we study the problem of low probability of intercept (LPI design for radar network and propose two novel LPI optimization schemes based on information-theoretic criteria. For a predefined threshold of target detection, Schleher intercept factor is minimized by optimizing transmission power allocation among netted radars in the network. Due to the lack of analytical closed-form expression for receiver operation characteristics (ROC, we employ two information-theoretic criteria, namely, Bhattacharyya distance and J-divergence as the metrics for target detection performance. The resulting nonconvex and nonlinear LPI optimization problems associated with different information-theoretic criteria are cast under a unified framework, and the nonlinear programming based genetic algorithm (NPGA is used to tackle the optimization problems in the framework. Numerical simulations demonstrate that our proposed LPI strategies are effective in enhancing the LPI performance for radar network.

Theoretical framework of the causes of construction time and cost overruns

Science.gov (United States)

Ullah, K.; Abdullah, A. H.; Nagapan, S.; Suhoo, S.; Khan, M. S.

2017-11-01

Any construction practitioner fundamental goal is to complete the projects within estimated duration and budgets, and expected quality targets. However, time and cost overruns are regular and universal phenomenon in construction projects and the construction projects in Malaysia has no exemption from the problems of time overrun and cost overrun. In order to accomplish the successful completion of construction projects on specified time and within planned cost, there are various factors that should be given serious attention so that issues such as time and cost overrun can be addressed. This paper aims to construct a framework for the causes of time overrun and cost overrun in construction projects of Malaysia. Based on the relevant literature review, causative factors of time overrun and cost overrun in Malaysian construction projects are summarized and the theoretical frameworks of the causes of construction time overrun and cost overrun is constructed. The developed frameworks for construction time and cost overruns based on the existing literature will assist the construction practitioners to plan the efficient approaches for achieving successful completion of the projects.

A Theoretical Framework for Organizing the Effect of the Internet on Cognitive Development

Science.gov (United States)

Johnson, Genevieve Marie

2006-01-01

The number of children and adolescents accessing the Internet as well as the amount of time online are steadily increasing. The most common online activities include playing video games, navigating web sites, and communicating via chat rooms, email, and instant messaging. A theoretical framework for understanding the effects of Internet use on…

Theoretical framework for government information service delivery to deep rural communities in South Africa

CSIR Research Space (South Africa)

Mvelase, PS

2009-10-01

Full Text Available This paper reports on a study to determine the information requirements of communities in deep rural areas on government services and how this information can be made available to them. The study then proposes an e-government theoretical framework...

A Framework for the Game-theoretic Analysis of Censorship Resistance

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Elahi Tariq

2016-10-01

Full Text Available We present a game-theoretic analysis of optimal solutions for interactions between censors and censorship resistance systems (CRSs by focusing on the data channel used by the CRS to smuggle clients’ data past the censors. This analysis leverages the inherent errors (false positives and negatives made by the censor when trying to classify traffic as either non-circumvention traffic or as CRS traffic, as well as the underlying rate of CRS traffic. We identify Nash equilibrium solutions for several simple censorship scenarios and then extend those findings to more complex scenarios where we find that the deployment of a censorship apparatus does not qualitatively change the equilibrium solutions, but rather only affects the amount of traffic a CRS can support before being blocked. By leveraging these findings, we describe a general framework for exploring and identifying optimal strategies for the censorship circumventor, in order to maximize the amount of CRS traffic not blocked by the censor. We use this framework to analyze several scenarios with multiple data-channel protocols used as cover for the CRS. We show that it is possible to gain insights through this framework even without perfect knowledge of the censor’s (secret values for the parameters in their utility function.

The Pedagogy of Primary Historical Sources in Mathematics: Classroom Practice Meets Theoretical Frameworks

Science.gov (United States)

Barnett, Janet Heine; Lodder, Jerry; Pengelley, David

2014-01-01

We analyze our method of teaching with primary historical sources within the context of theoretical frameworks for the role of history in teaching mathematics developed by Barbin, Fried, Jahnke, Jankvist, and Kjeldsen and Blomhøj, and more generally from the perspective of Sfard's theory of learning as communication. We present case studies…

Media’s role in pro-environmental practice changes – a theoretical and methodological framework

DEFF Research Database (Denmark)

Petersen, Lars Kjerulf

The aim of this paper is to present the theoretical framework and some preliminary findings from a research project investigating the metabolism of meanings between public communication and socio-material practice. The project seeks to integrate media analyses with practice theory and actor-netwo...

Theoretical frameworks used to discuss ethical issues in private physiotherapy practice and proposal of a new ethical tool.

Science.gov (United States)

Drolet, Marie-Josée; Hudon, Anne

2015-02-01

In the past, several researchers in the field of physiotherapy have asserted that physiotherapy clinicians rarely use ethical knowledge to solve ethical issues raised by their practice. Does this assertion still hold true? Do the theoretical frameworks used by researchers and clinicians allow them to analyze thoroughly the ethical issues they encounter in their everyday practice? In our quest for answers, we conducted a literature review and analyzed the ethical theoretical frameworks used by physiotherapy researchers and clinicians to discuss the ethical issues raised by private physiotherapy practice. Our final analysis corpus consisted of thirty-nine texts. Our main finding is that researchers and clinicians in physiotherapy rarely use ethical knowledge to analyze the ethical issues raised in their practice and that gaps exist in the theoretical frameworks currently used to analyze these issues. Consequently, we developed, for ethical analysis, a four-part prism which we have called the Quadripartite Ethical Tool (QET). This tool can be incorporated into existing theoretical frameworks to enable professionals to integrate ethical knowledge into their ethical analyses. The innovative particularity of the QET is that it encompasses three ethical theories (utilitarism, deontologism, and virtue ethics) and axiological ontology (professional values) and also draws on both deductive and inductive approaches. It is our hope that this new tool will help researchers and clinicians integrate ethical knowledge into their analysis of ethical issues and contribute to fostering ethical analyses that are grounded in relevant philosophical and axiological foundations.

Engagement in smartcities. Design of a framework of Theoretical analysis applied to citizen participation

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María E. Cortés-Cediel

2018-05-01

Full Text Available Engagement can be defined as a psychological state in which an individual focuses all her attention and enjoys the activity she is doing. The literature highlights the importance of improving this in citizen participation by governments and administrations. However, to the best of our knowledge, the literature does not offer clues about how engagement in citizen participation can be improved. This paper aims to develop a theoretical framework of citizen engagement for citizen participation in the context of smart cities. To this end, we first provide a definition of engagement, and describe some of its main characteristics. Next, we present a review of the literature on citizen participation tools in smart cities, analyzing if such tools do influence engagement attributes. The main outcomes of the study are the elaboration of a theoretical framework that integrates characteristic attributes of engagement in the field of citizen participation, and the identification of participation tools analyzing whether they can be designed to increase citizen engagement levels.

Mindfulness and Cardiovascular Disease Risk: State of the Evidence, Plausible Mechanisms, and Theoretical Framework

Science.gov (United States)

Schuman-Olivier, Zev; Britton, Willoughby B.; Fresco, David M.; Desbordes, Gaelle; Brewer, Judson A.; Fulwiler, Carl

2016-01-01

The purpose of this review is to provide (1) a synopsis on relations of mindfulness with cardiovascular disease (CVD) and major CVD risk factors, and (2) an initial consensus-based overview of mechanisms and theoretical framework by which mindfulness might influence CVD. Initial evidence, often of limited methodological quality, suggests possible impacts of mindfulness on CVD risk factors including physical activity, smoking, diet, obesity, blood pressure, and diabetes regulation. Plausible mechanisms include (1) improved attention control (e.g., ability to hold attention on experiences related to CVD risk, such as smoking, diet, physical activity, and medication adherence), (2) emotion regulation (e.g., improved stress response, self-efficacy, and skills to manage craving for cigarettes, palatable foods, and sedentary activities), and (3) self-awareness (e.g., self-referential processing and awareness of physical sensations due to CVD risk factors). Understanding mechanisms and theoretical framework should improve etiologic knowledge, providing customized mindfulness intervention targets that could enable greater mindfulness intervention efficacy. PMID:26482755

Theoretical and hypothetical framework for research on political socialization process in the family

Directory of Open Access Journals (Sweden)

Čičkarić Lilijana

2005-01-01

Full Text Available The aim of the article is to sum up theoretical and hypothetical framework for empirical research of political socialization process in the family in Serbian society nowadays. The investigation focuses on two theoretical concepts, political socialization and generation as a sociological paradigm. Two methodological approaches are applied. First is interactive model of political socialization, based on analysis of relations between individual who is socialized, agents of political socialization, dominant political system and peripheral social sub-systems. The second one tests interactive relation of generation, lifecycle and effects of epoch. It is suitable for definition of certain historical periods with active role of political.

A unified theoretical framework for mapping models for the multi-state Hamiltonian.

Science.gov (United States)

Liu, Jian

2016-11-28

We propose a new unified theoretical framework to construct equivalent representations of the multi-state Hamiltonian operator and present several approaches for the mapping onto the Cartesian phase space. After mapping an F-dimensional Hamiltonian onto an F+1 dimensional space, creation and annihilation operators are defined such that the F+1 dimensional space is complete for any combined excitation. Commutation and anti-commutation relations are then naturally derived, which show that the underlying degrees of freedom are neither bosons nor fermions. This sets the scene for developing equivalent expressions of the Hamiltonian operator in quantum mechanics and their classical/semiclassical counterparts. Six mapping models are presented as examples. The framework also offers a novel way to derive such as the well-known Meyer-Miller model.

Frequency Analysis of Gradient Estimators in Volume Rendering

NARCIS (Netherlands)

Bentum, Marinus Jan; Lichtenbelt, Barthold B.A.; Malzbender, Tom

1996-01-01

Gradient information is used in volume rendering to classify and color samples along a ray. In this paper, we present an analysis of the theoretically ideal gradient estimator and compare it to some commonly used gradient estimators. A new method is presented to calculate the gradient at arbitrary

theoretical and experimental study of plasma acceleration by means of R.F. and static magnetic field gradient

International Nuclear Information System (INIS)

Bardet, Rene; Consoli, Terenzio; Geller, Richard

1964-09-01

In the first part of the paper, the theory of the physical mechanism of ion dragging by accelerated electrons due to the superimposition of the gradient of a electromagnetic field and the gradient of a static magnetic field, is described. The resulting trajectory of the electrons is a helicoid and one shows the variations of the diameter and the path of the spirals along the axis as a function of the difference between the gyrofrequency and the applied R.F. frequency. The ion acceleration is due to an electron space charge effect. The grouping of the equations of the electronic and ionic fluid motions leads to the introduction of a tensor mass: along the x and y direction the transverse motion of the fluid is controlled by the relativistic mass of electrons whereas along the z direction the axial motion is determined by the ionic mass. Then we deduce physical consequences of the theoretical study and give three experimental evidences. The second part of the paper is devoted to the experimental device called Pleiade which allowed us to verify some of the theoretical predictions. Pleiade produces a D.C. operating plasma beam in which the electrons exhibit radially oriented energies whereas the ionic energy is mainly axial. The experimental results indicate that the energy of the particles is in the keV range. In the third part we deal with the reflecting properties of the device. We show that the R.F. static magnetic field gradients are not only capable of accelerating a Plasma beam along the axially decreasing magnetic field, but are also capable of stopping and reflecting such a beam when the latter is moving along an axially increasing magnetic field. We describe finally a plasma accumulation experiment in which two symmetric structures form simultaneously an accelerator and a 'dynamic mirror' for the particles. Evidence of accumulation is given. (authors) [fr

A theoretical framework for the associations between identity and psychopathology.

Science.gov (United States)

Klimstra, Theo A; Denissen, Jaap J A

2017-11-01

Identity research largely emerged from clinical observations. Decades of empirical work advanced the field in refining existing approaches and adding new approaches. Furthermore, the existence of linkages of identity with psychopathology is now well established. Unfortunately, both the directionality of effects between identity aspects and psychopathology symptoms, and the mechanisms underlying associations are unclear. In the present paper, we present a new framework to inspire hypothesis-driven empirical research to overcome this limitation. The framework has a basic resemblance to theoretical models for the study of personality and psychopathology, so we provide examples of how these might apply to the study of identity. Next, we explain that unique features of identity may come into play in individuals suffering from psychopathology that are mostly related to the content of one's identity. These include pros and cons of identifying with one's diagnostic label. Finally, inspired by Hermans' dialogical self theory and principles derived from Piaget's, Swann's and Kelly's work, we delineate a framework with identity at the core of an individual multidimensional space. In this space, psychopathology symptoms have a known distance (representing relevance) to one's identity, and individual multidimensional spaces are connected to those of other individuals in one's social network. We discuss methodological (quantitative and qualitative, idiographic and nomothetic) and statistical procedures (multilevel models and network models) to test the framework. Resulting evidence can boost the field of identity research in demonstrating its high practical relevance for the emergence and conservation of psychopathology. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

A game theoretic framework for analyzing re-identification risk.

Directory of Open Access Journals (Sweden)

Zhiyu Wan

Full Text Available Given the potential wealth of insights in personal data the big databases can provide, many organizations aim to share data while protecting privacy by sharing de-identified data, but are concerned because various demonstrations show such data can be re-identified. Yet these investigations focus on how attacks can be perpetrated, not the likelihood they will be realized. This paper introduces a game theoretic framework that enables a publisher to balance re-identification risk with the value of sharing data, leveraging a natural assumption that a recipient only attempts re-identification if its potential gains outweigh the costs. We apply the framework to a real case study, where the value of the data to the publisher is the actual grant funding dollar amounts from a national sponsor and the re-identification gain of the recipient is the fine paid to a regulator for violation of federal privacy rules. There are three notable findings: 1 it is possible to achieve zero risk, in that the recipient never gains from re-identification, while sharing almost as much data as the optimal solution that allows for a small amount of risk; 2 the zero-risk solution enables sharing much more data than a commonly invoked de-identification policy of the U.S. Health Insurance Portability and Accountability Act (HIPAA; and 3 a sensitivity analysis demonstrates these findings are robust to order-of-magnitude changes in player losses and gains. In combination, these findings provide support that such a framework can enable pragmatic policy decisions about de-identified data sharing.

Development of a theoretical framework for analyzing cerebrospinal fluid dynamics

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Vedel Søren

2009-09-01

Full Text Available Abstract Background To date hydrocephalus researchers acknowledge the need for rigorous but utilitarian fluid mechanics understanding and methodologies in studying normal and hydrocephalic intracranial dynamics. Pressure volume models and electric circuit analogs introduced pressure into volume conservation; but control volume analysis enforces independent conditions on pressure and volume. Previously, utilization of clinical measurements has been limited to understanding of the relative amplitude and timing of flow, volume and pressure waveforms; qualitative approaches without a clear framework for meaningful quantitative comparison. Methods Control volume analysis is presented to introduce the reader to the theoretical background of this foundational fluid mechanics technique for application to general control volumes. This approach is able to directly incorporate the diverse measurements obtained by clinicians to better elucidate intracranial dynamics and progression to disorder. Results Several examples of meaningful intracranial control volumes and the particular measurement sets needed for the analysis are discussed. Conclusion Control volume analysis provides a framework to guide the type and location of measurements and also a way to interpret the resulting data within a fundamental fluid physics analysis.

Unpacking Teacher-Researcher Collaboration with Three Theoretical Frameworks: A Case of Expansive Learning Activity?

Science.gov (United States)

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…

Experimental and theoretical studies of oxygen gradients in rat pial microvessels

OpenAIRE

Sharan, Maithili; Vovenko, Eugene P; Vadapalli, Arjun; Popel, Aleksander S; Pittman, Roland N

2008-01-01

Using modified oxygen needle microelectrodes and intravital videomicroscopy, measurements were made of tissue oxygen tension (PO2) profiles near cortical arterioles and transmural PO2 gradients in the pial arterioles of the rat. Under control conditions, the transmural PO2 gradient averaged 1.17 ± 0.06 mm Hg/μm (mean ± s.e., n = 40). Local arteriolar dilation resulted in a marked decrease in the transmural PO2 gradient to 0.68 ± 0.04 mm Hg/μm (P < 0.001, n = 38). The major finding of this stu...

The PyZgoubi framework and the simulation of dynamic aperture in fixed-field alternating-gradient accelerators

International Nuclear Information System (INIS)

Tygier, S.; Appleby, R.B.; Garland, J.M.; Hock, K.; Owen, H.; Kelliher, D.J.; Sheehy, S.L.

2015-01-01

We present PyZgoubi, a framework that has been developed based on the tracking engine Zgoubi to model, optimise and visualise the dynamics in particle accelerators, especially fixed-field alternating-gradient (FFAG) accelerators. We show that PyZgoubi abstracts Zgoubi by wrapping it in an easy-to-use Python framework in order to allow simple construction, parameterisation, visualisation and optimisation of FFAG accelerator lattices. Its object oriented design gives it the flexibility and extensibility required for current novel FFAG design. We apply PyZgoubi to two example FFAGs; this includes determining the dynamic aperture of the PAMELA medical FFAG in the presence of magnet misalignments, and illustrating how PyZgoubi may be used to optimise FFAGs. We also discuss a robust definition of dynamic aperture in an FFAG and show its implementation in PyZgoubi

The PyZgoubi framework and the simulation of dynamic aperture in fixed-field alternating-gradient accelerators

Energy Technology Data Exchange (ETDEWEB)

Tygier, S., E-mail: sam.tygier@hep.manchester.ac.uk [Cockcroft Accelerator Group, The University of Manchester (United Kingdom); Appleby, R.B., E-mail: robert.appleby@manchester.ac.uk [Cockcroft Accelerator Group, The University of Manchester (United Kingdom); Garland, J.M. [Cockcroft Accelerator Group, The University of Manchester (United Kingdom); Hock, K. [University of Liverpool (United Kingdom); Owen, H. [Cockcroft Accelerator Group, The University of Manchester (United Kingdom); Kelliher, D.J.; Sheehy, S.L. [STFC Rutherford Appleton Laboratory (United Kingdom)

2015-03-01

We present PyZgoubi, a framework that has been developed based on the tracking engine Zgoubi to model, optimise and visualise the dynamics in particle accelerators, especially fixed-field alternating-gradient (FFAG) accelerators. We show that PyZgoubi abstracts Zgoubi by wrapping it in an easy-to-use Python framework in order to allow simple construction, parameterisation, visualisation and optimisation of FFAG accelerator lattices. Its object oriented design gives it the flexibility and extensibility required for current novel FFAG design. We apply PyZgoubi to two example FFAGs; this includes determining the dynamic aperture of the PAMELA medical FFAG in the presence of magnet misalignments, and illustrating how PyZgoubi may be used to optimise FFAGs. We also discuss a robust definition of dynamic aperture in an FFAG and show its implementation in PyZgoubi.

Opioid Prescribing After Curative-Intent Surgery: A Qualitative Study Using the Theoretical Domains Framework.

Science.gov (United States)

Lee, Jay S; Parashar, Vartika; Miller, Jacquelyn B; Bremmer, Samantha M; Vu, Joceline V; Waljee, Jennifer F; Dossett, Lesly A

2018-07-01

Excessive opioid prescribing is common after curative-intent surgery, but little is known about what factors influence prescribing behaviors among surgeons. To identify targets for intervention, we performed a qualitative study of opioid prescribing after curative-intent surgery using the Theoretical Domains Framework, a well-established implementation science method for identifying factors influencing healthcare provider behavior. Prior to data collection, we constructed a semi-structured interview guide to explore decision making for opioid prescribing. We then conducted interviews with surgical oncology providers at a single comprehensive cancer center. Interviews were recorded, transcribed verbatim, then independently coded by two investigators using the Theoretical Domains Framework to identify theoretical domains relevant to opioid prescribing. Relevant domains were then linked to behavior models to select targeted interventions likely to improve opioid prescribing. Twenty-one subjects were interviewed from November 2016 to May 2017, including attending surgeons, resident surgeons, physician assistants, and nurses. Five theoretical domains emerged as relevant to opioid prescribing: environmental context and resources; social influences; beliefs about consequences; social/professional role and identity; and goals. Using these domains, three interventions were identified as likely to change opioid prescribing behavior: (1) enablement (deploy nurses during preoperative visits to counsel patients on opioid use); (2) environmental restructuring (provide on-screen prompts with normative data on the quantity of opioid prescribed); and (3) education (provide prescribing guidelines). Key determinants of opioid prescribing behavior after curative-intent surgery include environmental and social factors. Interventions targeting these factors are likely to improve opioid prescribing in surgical oncology.

A THEORETICAL AND NUMERICAL STUDY OF THERMOSOLUTAL CONVECTION: STABILITY OF A SALINITY GRADIENT SOLAR POND

Directory of Open Access Journals (Sweden)

Djamel Kalache

2011-01-01

Full Text Available A theoretical and numerical study of the effect of thermodiffusion on the stability of a gradient layer is presented. It intends to clarify the mechanisms of fluid dynamics and the processes which occur in a salinity gradient solar pond. A mathematical modelling is developed to describe the thermodiffusion contribution on the solar pond where thermal, radiative, and massive fluxes are coupled in the double diffusion. More realistic boundary conditions for temperature and concentration profiles are used. Our results are compared with those obtained experimentally by authors without extracting the heat flux from the storage zone. We have considered the stability analysis of the equilibrium solution. We assumed that the perturbation of quantities such as velocity, temperature, and concentration are infinitesimal. Linearized equations satisfying appropriate prescribed boundary conditions are then obtained and expanded into polynomials form. The Galerkin method along with a symbolic algebra code (Maple are used to solve these equations. The effect of the separation coefficient y is analyzed in the positive and negative case. We have also numerically compared the critical Rayleigh numbers for the onset of convection with those obtained by the linear stability analysis for Le = 100, µa = 0.8, and f = 0.5.

Connecting single cell to collective cell behavior in a unified theoretical framework

Science.gov (United States)

George, Mishel; Bullo, Francesco; Campàs, Otger

Collective cell behavior is an essential part of tissue and organ morphogenesis during embryonic development, as well as of various disease processes, such as cancer. In contrast to many in vitro studies of collective cell migration, most cases of in vivo collective cell migration involve rather small groups of cells, with large sheets of migrating cells being less common. The vast majority of theoretical descriptions of collective cell behavior focus on large numbers of cells, but fail to accurately capture the dynamics of small groups of cells. Here we introduce a low-dimensional theoretical description that successfully captures single cell migration, cell collisions, collective dynamics in small groups of cells, and force propagation during sheet expansion, all within a common theoretical framework. Our description is derived from first principles and also includes key phenomenological aspects of cell migration that control the dynamics of traction forces. Among other results, we explain the counter-intuitive observations that pairs of cells repel each other upon collision while they behave in a coordinated manner within larger clusters.

Ecological Dynamics as a Theoretical Framework for Development of Sustainable Behaviours towards the Environment

Science.gov (United States)

Brymer, Eric; Davids, Keith

2013-01-01

This paper proposes how the theoretical framework of ecological dynamics can provide an influential model of the learner and the learning process to pre-empt effective behaviour changes. Here we argue that ecological dynamics supports a well-established model of the learner ideally suited to the environmental education context because of its…

Developing a Theoretical Framework for Examining Student Understanding of Fractional Concepts: An Historical Accounting

Science.gov (United States)

Cooper, Susan M.; Wilkerson, Trena L.; Montgomery, Mark; Mechell, Sara; Arterbury, Kristin; Moore, Sherrie

2012-01-01

In 2007, a group of mathematics educators and researchers met to examine rational numbers and why children have such an issue with them. An extensive review of the literature on fractional understanding was conducted. The ideas in that literature were then consolidated into a theoretical framework for examining fractions. Once that theoretical…

Technical and theoretical considerations about gradient perfusion culture for epithelia used in tissue engineering, biomaterial testing and pharmaceutical research

International Nuclear Information System (INIS)

Minuth, Will W; Strehl, Raimund

2007-01-01

Epithelia act as biological barriers, which are exposed to different environments at the luminal and basal sides. To simulate this situation and to improve functional features an in vitro gradient perfusion culture technique was developed in our laboratory. This innovative technique appears to be simple at first sight, but the performance needs practical and theoretical knowledge. To harvest intact epithelia after a long-term gradient culture period of many days, leakage, edge damage and pressure differences in the system have to be avoided so that the epithelial barrier function is maintained continuously. Unexpectedly, one of the major obstacles are micro-injuries in the epithelia caused by gas bubbles, which arise during transportation of the medium or due to respiration of the cultured tissue. Gas bubbles randomly accumulate either at the luminal or basal fluid flow of the gradient perfusion culture container. This phenomenon results in fluid pressure differences between the luminal and basal perfusion compartments of the gradient container, which in turn leads to damage of the barrier function. Consequently, the content of gas bubbles in the transported culture medium has to be minimized. Thus, our technical concept is the reduction of gas bubbles while keeping the content of oxygen constant. To follow this strategy we developed a new type of screw cap for media bottles specifically designed to allow fluid contact only with tube and not with cap material. Furthermore, a gas expander module separates gas bubbles from the liquid phase during transportation of the medium. Finally, a new type of gradient culture container allows a permanent elimination of transported gas bubbles. Application of this innovative equipment optimizes the parallel transportation of fluid in the luminal and basal compartments of a gradient culture container. (topical review)

Technical and theoretical considerations about gradient perfusion culture for epithelia used in tissue engineering, biomaterial testing and pharmaceutical research

Energy Technology Data Exchange (ETDEWEB)

Minuth, Will W [Department of Molecular and Cellular Anatomy, University of Regensburg, D-93053 Regensburg, University Street 31 (Germany); Strehl, Raimund [Cellartis AB, S-41346 Goeteborg, Arvid Wallgrens Backe 20 (Sweden)

2007-06-01

Epithelia act as biological barriers, which are exposed to different environments at the luminal and basal sides. To simulate this situation and to improve functional features an in vitro gradient perfusion culture technique was developed in our laboratory. This innovative technique appears to be simple at first sight, but the performance needs practical and theoretical knowledge. To harvest intact epithelia after a long-term gradient culture period of many days, leakage, edge damage and pressure differences in the system have to be avoided so that the epithelial barrier function is maintained continuously. Unexpectedly, one of the major obstacles are micro-injuries in the epithelia caused by gas bubbles, which arise during transportation of the medium or due to respiration of the cultured tissue. Gas bubbles randomly accumulate either at the luminal or basal fluid flow of the gradient perfusion culture container. This phenomenon results in fluid pressure differences between the luminal and basal perfusion compartments of the gradient container, which in turn leads to damage of the barrier function. Consequently, the content of gas bubbles in the transported culture medium has to be minimized. Thus, our technical concept is the reduction of gas bubbles while keeping the content of oxygen constant. To follow this strategy we developed a new type of screw cap for media bottles specifically designed to allow fluid contact only with tube and not with cap material. Furthermore, a gas expander module separates gas bubbles from the liquid phase during transportation of the medium. Finally, a new type of gradient culture container allows a permanent elimination of transported gas bubbles. Application of this innovative equipment optimizes the parallel transportation of fluid in the luminal and basal compartments of a gradient culture container. (topical review)

The Influence of the Pedagogical Content Knowledge Theoretical Framework on Research on Preservice Teacher Education

Science.gov (United States)

Mecoli, Storey

2013-01-01

Pedagogical Content Knowledge, Lee S. Shulman's theoretical framework, has had a substantial influence on research in preservice teacher education, and consequently, schools of education. This review builds from Grossman's case studies that concluded that beginning teachers provided with excellent teacher education developed more substantial PCK…

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

Science.gov (United States)

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

2017-01-26

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

First-Year Biology Students' Understandings of Meiosis: An Investigation Using a Structural Theoretical Framework

Science.gov (United States)

Quinn, Frances; Pegg, John; Panizzon, Debra

2009-01-01

Meiosis is a biological concept that is both complex and important for students to learn. This study aims to explore first-year biology students' explanations of the process of meiosis, using an explicit theoretical framework provided by the Structure of the Observed Learning Outcome (SOLO) model. The research was based on responses of 334…

Gradient Boosting Machines, A Tutorial

Directory of Open Access Journals (Sweden)

Alexey eNatekin

2013-12-01

Full Text Available Gradient boosting machines are a family of powerful machine-learning techniques that have shown considerable success in a wide range of practical applications. They are highly customizable to the particular needs of the application, like being learned with respect to different loss functions. This article gives a tutorial introduction into the methodology of gradient boosting methods. A theoretical information is complemented with many descriptive examples and illustrations which cover all the stages of the gradient boosting model design. Considerations on handling the model complexity are discussed. A set of practical examples of gradient boosting applications are presented and comprehensively analyzed.

Soil Carbon Dynamics Along an Elevation Gradient in the Southern Appalachian Mountains

Energy Technology Data Exchange (ETDEWEB)

Garten Jr., C.T.

2004-04-13

The role of soil C dynamics in the exchange of CO{sub 2} between the terrestrial biosphere and the atmosphere is at the center of many science questions related to global climate change. The purpose of this report is to summarize measured trends in environmental factors and ecosystem processes that affect soil C balance along elevation gradients in the southern Appalachian Mountains of eastern Tennessee and western North Carolina, USA. Three environmental factors that have potentially significant effects on soil C dynamics (temperature, precipitation, and soil N availability) vary in a predictable manner with altitude. Forest soil C stocks and calculated turnover times of labile soil C increase with elevation, and there is an apparent inverse relationship between soil C storage and mean annual temperature. Relationships between climate variables and soil C dynamics along elevation gradients must be interpreted with caution because litter chemistry, soil moisture, N availability, and temperature are confounded; all potentially interact in complex ways to regulate soil C storage through effects on decomposition. Some recommendations are presented for untangling these complexities. It is concluded that past studies along elevation gradients have contributed to a better but not complete understanding of environmental factors and processes that potentially affect soil C balance. Furthermore, there are advantages linked to the use of elevation gradients as an approach to climate change research when hypotheses are placed in a strong theoretical or mechanistic framework. Climate change research along elevation gradients can be both convenient and economical. More importantly, ecosystem processes and attributes affecting soil C dynamics along elevation gradients are usually the product of the long-term interactions between climate, vegetation, and soil type. Investigations along elevation gradients are a useful approach to the study of environmental change, and its effect

The Price Equation, Gradient Dynamics, and Continuous Trait Game Theory.

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Lehtonen, Jussi

2018-01-01

A recent article convincingly nominated the Price equation as the fundamental theorem of evolution and used it as a foundation to derive several other theorems. A major section of evolutionary theory that was not addressed is that of game theory and gradient dynamics of continuous traits with frequency-dependent fitness. Deriving fundamental results in these fields under the unifying framework of the Price equation illuminates similarities and differences between approaches and allows a simple, unified view of game-theoretical and dynamic concepts. Using Taylor polynomials and the Price equation, I derive a dynamic measure of evolutionary change, a condition for singular points, the convergence stability criterion, and an alternative interpretation of evolutionary stability. Furthermore, by applying the Price equation to a multivariable Taylor polynomial, the direct fitness approach to kin selection emerges. Finally, I compare these results to the mean gradient equation of quantitative genetics and the canonical equation of adaptive dynamics.

How a High-Gradient Magnetic Field Could Affect Cell Life

Science.gov (United States)

Zablotskii, Vitalii; Polyakova, Tatyana; Lunov, Oleg; Dejneka, Alexandr

2016-01-01

The biological effects of high-gradient magnetic fields (HGMFs) have steadily gained the increased attention of researchers from different disciplines, such as cell biology, cell therapy, targeted stem cell delivery and nanomedicine. We present a theoretical framework towards a fundamental understanding of the effects of HGMFs on intracellular processes, highlighting new directions for the study of living cell machinery: changing the probability of ion-channel on/off switching events by membrane magneto-mechanical stress, suppression of cell growth by magnetic pressure, magnetically induced cell division and cell reprograming, and forced migration of membrane receptor proteins. By deriving a generalized form for the Nernst equation, we find that a relatively small magnetic field (approximately 1 T) with a large gradient (up to 1 GT/m) can significantly change the membrane potential of the cell and thus have a significant impact on not only the properties and biological functionality of cells but also cell fate. PMID:27857227

How a High-Gradient Magnetic Field Could Affect Cell Life

Science.gov (United States)

Zablotskii, Vitalii; Polyakova, Tatyana; Lunov, Oleg; Dejneka, Alexandr

2016-11-01

The biological effects of high-gradient magnetic fields (HGMFs) have steadily gained the increased attention of researchers from different disciplines, such as cell biology, cell therapy, targeted stem cell delivery and nanomedicine. We present a theoretical framework towards a fundamental understanding of the effects of HGMFs on intracellular processes, highlighting new directions for the study of living cell machinery: changing the probability of ion-channel on/off switching events by membrane magneto-mechanical stress, suppression of cell growth by magnetic pressure, magnetically induced cell division and cell reprograming, and forced migration of membrane receptor proteins. By deriving a generalized form for the Nernst equation, we find that a relatively small magnetic field (approximately 1 T) with a large gradient (up to 1 GT/m) can significantly change the membrane potential of the cell and thus have a significant impact on not only the properties and biological functionality of cells but also cell fate.

Organizational culture and organizational effectiveness: a meta-analytic investigation of the competing values framework's theoretical suppositions.

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Hartnell, Chad A; Ou, Amy Yi; Kinicki, Angelo

2011-07-01

We apply Quinn and Rohrbaugh's (1983) competing values framework (CVF) as an organizing taxonomy to meta-analytically test hypotheses about the relationship between 3 culture types and 3 major indices of organizational effectiveness (employee attitudes, operational performance [i.e., innovation and product and service quality], and financial performance). The paper also tests theoretical suppositions undergirding the CVF by investigating the framework's nomological validity and proposed internal structure (i.e., interrelationships among culture types). Results based on data from 84 empirical studies with 94 independent samples indicate that clan, adhocracy, and market cultures are differentially and positively associated with the effectiveness criteria, though not always as hypothesized. The findings provide mixed support for the CVF's nomological validity and fail to support aspects of the CVF's proposed internal structure. We propose an alternative theoretical approach to the CVF and delineate directions for future research.

Trajectories on the path to reciprocity-A theoretical framework for collaborating with socioeconomically disadvantaged communities.

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Minas, Maria; Ribeiro, Maria Teresa; Anglin, James P

2018-01-01

The importance of cultivating connection to enhance individual, relational and collective well-being is gaining attention in the current literature on building community. Although these goals are being increasingly considered, the concept of reciprocity has been less prominent than may be warranted in the field of psychology. This article presents a theoretical framework on the dynamics of reciprocity which resulted from grounded theory (GT) research involving 2 complementary studies. The first study involved 22 participants from different socioeconomic backgrounds engaged in "reflecting-team with appreciative audiences" sessions (Madsen, 2007) in Portugal. The second study involved participant observation of 15 community programs recognized as good-practices in collaboration with socioeconomically disadvantaged participants, at national and international levels, across 9 countries. The theoretical framework emphasizes the centrality of building reciprocity for the development of individuals, families, communities, and programs. It integrates the trajectories of reciprocity; quadrants reflecting the standpoints assumed according to socioeconomic and cultural positions; basic social-psychological processes inherent to the process of building reciprocity; and characterizes different types of programs. The resulting framework is analyzed in relation to prior literature for a broader understanding of synergies and challenges, and the article concludes by suggesting implications for further research and practice. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

A theoretical framework for modeling dilution enhancement of non-reactive solutes in heterogeneous porous media.

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de Barros, F P J; Fiori, A; Boso, F; Bellin, A

2015-01-01

Spatial heterogeneity of the hydraulic properties of geological porous formations leads to erratically shaped solute clouds, thus increasing the edge area of the solute body and augmenting the dilution rate. In this study, we provide a theoretical framework to quantify dilution of a non-reactive solute within a steady state flow as affected by the spatial variability of the hydraulic conductivity. Embracing the Lagrangian concentration framework, we obtain explicit semi-analytical expressions for the dilution index as a function of the structural parameters of the random hydraulic conductivity field, under the assumptions of uniform-in-the-average flow, small injection source and weak-to-mild heterogeneity. Results show how the dilution enhancement of the solute cloud is strongly dependent on both the statistical anisotropy ratio and the heterogeneity level of the porous medium. The explicit semi-analytical solution also captures the temporal evolution of the dilution rate; for the early- and late-time limits, the proposed solution recovers previous results from the literature, while at intermediate times it reflects the increasing interplay between large-scale advection and local-scale dispersion. The performance of the theoretical framework is verified with high resolution numerical results and successfully tested against the Cape Cod field data. Copyright © 2015 Elsevier B.V. All rights reserved.

Individual behavioral phenotypes: an integrative meta-theoretical framework. Why "behavioral syndromes" are not analogs of "personality".

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Uher, Jana

2011-09-01

Animal researchers are increasingly interested in individual differences in behavior. Their interpretation as meaningful differences in behavioral strategies stable over time and across contexts, adaptive, heritable, and acted upon by natural selection has triggered new theoretical developments. However, the analytical approaches used to explore behavioral data still address population-level phenomena, and statistical methods suitable to analyze individual behavior are rarely applied. I discuss fundamental investigative principles and analytical approaches to explore whether, in what ways, and under which conditions individual behavioral differences are actually meaningful. I elaborate the meta-theoretical ideas underlying common theoretical concepts and integrate them into an overarching meta-theoretical and methodological framework. This unravels commonalities and differences, and shows that assumptions of analogy to concepts of human personality are not always warranted and that some theoretical developments may be based on methodological artifacts. Yet, my results also highlight possible directions for new theoretical developments in animal behavior research. Copyright © 2011 Wiley Periodicals, Inc.

High Gradient Accelerator Research

International Nuclear Information System (INIS)

Temkin, Richard

2016-01-01

The goal of the MIT program of research on high gradient acceleration is the development of advanced acceleration concepts that lead to a practical and affordable next generation linear collider at the TeV energy level. Other applications, which are more near-term, include accelerators for materials processing; medicine; defense; mining; security; and inspection. The specific goals of the MIT program are: • Pioneering theoretical research on advanced structures for high gradient acceleration, including photonic structures and metamaterial structures; evaluation of the wakefields in these advanced structures • Experimental research to demonstrate the properties of advanced structures both in low-power microwave cold test and high-power, high-gradient test at megawatt power levels • Experimental research on microwave breakdown at high gradient including studies of breakdown phenomena induced by RF electric fields and RF magnetic fields; development of new diagnostics of the breakdown process • Theoretical research on the physics and engineering features of RF vacuum breakdown • Maintaining and improving the Haimson / MIT 17 GHz accelerator, the highest frequency operational accelerator in the world, a unique facility for accelerator research • Providing the Haimson / MIT 17 GHz accelerator facility as a facility for outside users • Active participation in the US DOE program of High Gradient Collaboration, including joint work with SLAC and with Los Alamos National Laboratory; participation of MIT students in research at the national laboratories • Training the next generation of Ph. D. students in the field of accelerator physics.

When the Mannequin Dies, Creation and Exploration of a Theoretical Framework Using a Mixed Methods Approach.

Science.gov (United States)

Tripathy, Shreepada; Miller, Karen H; Berkenbosch, John W; McKinley, Tara F; Boland, Kimberly A; Brown, Seth A; Calhoun, Aaron W

2016-06-01

Controversy exists in the simulation community as to the emotional and educational ramifications of mannequin death due to learner action or inaction. No theoretical framework to guide future investigations of learner actions currently exists. The purpose of our study was to generate a model of the learner experience of mannequin death using a mixed methods approach. The study consisted of an initial focus group phase composed of 11 learners who had previously experienced mannequin death due to action or inaction on the part of learners as defined by Leighton (Clin Simul Nurs. 2009;5(2):e59-e62). Transcripts were analyzed using grounded theory to generate a list of relevant themes that were further organized into a theoretical framework. With the use of this framework, a survey was generated and distributed to additional learners who had experienced mannequin death due to action or inaction. Results were analyzed using a mixed methods approach. Forty-one clinicians completed the survey. A correlation was found between the emotional experience of mannequin death and degree of presession anxiety (P framework. Using the previous approach, we created a model of the effect of mannequin death on the educational and psychological state of learners. We offer the final model as a guide to future research regarding the learner experience of mannequin death.

Individual Tariffs for Mobile Services: Theoretical Framework and a Computational Case in Mobile Music

OpenAIRE

Chen, Hong; Pau, Louis-François

2007-01-01

textabstractThis paper introduces individual tariffs at service and content bundle level in mobile communications. It gives a theoretical framework (economic, sociological) as well as a computational game solution method. The user can be an individual or a community. Individual tariffs are decided through interactions between the user and the supplier. A numerical example from mobile music illustrates the concepts.

Nature-Inspired 2D-Mosaic 3D-Gradient Mesoporous Framework: Bimetal Oxide Dual-Composite Strategy toward Ultrastable and High-Capacity Lithium Storage.

Science.gov (United States)

Yu, Jia; Wang, Yanlei; Mou, Lihui; Fang, Daliang; Chen, Shimou; Zhang, Suojiang

2018-02-27

In allusion to traditional transition-metal oxide (TMO) anodes for lithium-ion batteries, which face severe volume variation and poor conductivity, herein a bimetal oxide dual-composite strategy based on two-dimensional (2D)-mosaic three-dimensional (3D)-gradient design is proposed. Inspired by natural mosaic dominance phenomena, Zn 1-x Co x O/ZnCo 2 O 4 2D-mosaic-hybrid mesoporous ultrathin nanosheets serve as building blocks to assemble into a 3D Zn-Co hierarchical framework. Moreover, a series of derivative frameworks with high evolution are controllably synthesized, based on which a facile one-pot synthesis process can be developed. From a component-composite perspective, both Zn 1-x Co x O and ZnCo 2 O 4 provide superior conductivity due to bimetal doping effect, which is verified by density functional theory calculations. From a structure-composite perspective, 2D-mosaic-hybrid mode gives rise to ladder-type buffering and electrochemical synergistic effect, thus realizing mutual stabilization and activation between the mosaic pair, especially for Zn 1-x Co x O with higher capacity yet higher expansion. Moreover, the inside-out Zn-Co concentration gradient in 3D framework and rich oxygen vacancies further greatly enhance Li storage capability and stability. As a result, a high reversible capacity (1010 mA h g -1 ) and areal capacity (1.48 mA h cm -2 ) are attained, while ultrastable cyclability is obtained during high-rate and long-term cycles, rending great potential of our 2D-mosaic 3D-gradient design together with facile synthesis.

Commonalities between Disaster and Climate Change Risks for Health: A Theoretical Framework.

Science.gov (United States)

Banwell, Nicola; Rutherford, Shannon; Mackey, Brendan; Street, Roger; Chu, Cordia

2018-03-16

Disasters and climate change have significant implications for human health worldwide. Both climate change and the climate-sensitive hazards that result in disasters, are discussed in terms of direct and indirect impacts on health. A growing body of literature has argued for the need to link disaster risk reduction and climate change adaptation. However, there is limited articulation of the commonalities between these health impacts. Understanding the shared risk pathways is an important starting point for developing joint strategies for adapting to, and reducing, health risks. Therefore, this article discusses the common aspects of direct and indirect health risks of climate change and climate-sensitive disasters. Based on this discussion a theoretical framework is presented for understanding these commonalities. As such, this article hopes to extend the current health impact frameworks and provide a platform for further research exploring opportunities for linked adaptation and risk reduction strategies.

A Theoretical Framework for Soft-Information-Based Synchronization in Iterative (Turbo Receivers

Directory of Open Access Journals (Sweden)

Lottici Vincenzo

2005-01-01

Full Text Available This contribution considers turbo synchronization, that is to say, the use of soft data information to estimate parameters like carrier phase, frequency, or timing offsets of a modulated signal within an iterative data demodulator. In turbo synchronization, the receiver exploits the soft decisions computed at each turbo decoding iteration to provide a reliable estimate of some signal parameters. The aim of our paper is to show that such "turbo-estimation" approach can be regarded as a special case of the expectation-maximization (EM algorithm. This leads to a general theoretical framework for turbo synchronization that allows to derive parameter estimation procedures for carrier phase and frequency offset, as well as for timing offset and signal amplitude. The proposed mathematical framework is illustrated by simulation results reported for the particular case of carrier phase and frequency offsets estimation of a turbo-coded 16-QAM signal.

Commonalities between Disaster and Climate Change Risks for Health: A Theoretical Framework

Science.gov (United States)

Banwell, Nicola; Rutherford, Shannon; Mackey, Brendan; Street, Roger; Chu, Cordia

2018-01-01

Disasters and climate change have significant implications for human health worldwide. Both climate change and the climate-sensitive hazards that result in disasters, are discussed in terms of direct and indirect impacts on health. A growing body of literature has argued for the need to link disaster risk reduction and climate change adaptation. However, there is limited articulation of the commonalities between these health impacts. Understanding the shared risk pathways is an important starting point for developing joint strategies for adapting to, and reducing, health risks. Therefore, this article discusses the common aspects of direct and indirect health risks of climate change and climate-sensitive disasters. Based on this discussion a theoretical framework is presented for understanding these commonalities. As such, this article hopes to extend the current health impact frameworks and provide a platform for further research exploring opportunities for linked adaptation and risk reduction strategies. PMID:29547592

Commonalities between Disaster and Climate Change Risks for Health: A Theoretical Framework

Directory of Open Access Journals (Sweden)

Nicola Banwell

2018-03-01

Full Text Available Disasters and climate change have significant implications for human health worldwide. Both climate change and the climate-sensitive hazards that result in disasters, are discussed in terms of direct and indirect impacts on health. A growing body of literature has argued for the need to link disaster risk reduction and climate change adaptation. However, there is limited articulation of the commonalities between these health impacts. Understanding the shared risk pathways is an important starting point for developing joint strategies for adapting to, and reducing, health risks. Therefore, this article discusses the common aspects of direct and indirect health risks of climate change and climate-sensitive disasters. Based on this discussion a theoretical framework is presented for understanding these commonalities. As such, this article hopes to extend the current health impact frameworks and provide a platform for further research exploring opportunities for linked adaptation and risk reduction strategies.

Ultimate Gradient Limitation in Niobium Superconducting Accelerating Cavities

Energy Technology Data Exchange (ETDEWEB)

Checchin, Mattia [Illinois Inst. of Technology, Chicago, IL (United States); Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Grassellino, Anna [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Martinello, Martina [Illinois Inst. of Technology, Chicago, IL (United States); Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Posen, Sam [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Romanenko, Alexander [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Zasadzinski, John [Illinois Inst. of Technology, Chicago, IL (United States)

2016-06-01

The present study is addressed to the theoretical description of the ultimate gradient limitation in SRF cavities. Our intent is to exploit experimental data to confirm models which provide feed-backs on how to improve the current state-of-art. New theoretical insight on the cavities limiting factor can be suitable to improve the quench field of N-doped cavities, and therefore to take advantage of high Q₀ at high gradients.

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

Science.gov (United States)

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…

Video Games and the Militarisation of Society: Towards a Theoretical and Conceptual Framework

OpenAIRE

Martino , John

2012-01-01

Part 4: Section 3: ICT for Peace and War; International audience; This paper outlines the relationship between military themed or oriented video and computer games and the process of militarisation. A theoretical and analytical framework which draws on elements of sociology, cultural studies and media analysis is required to help to understand the complex interplay between entertainment in the form of playable media, the military and the maintenance of Empire. At one level games can be descri...

Aims and theoretical frameworks in nursing students' Bachelor's theses in Sweden: A descriptive study.

Science.gov (United States)

Silén, Marit; Johansson, Linda

2016-02-01

Nursing students' independent projects in Sweden not only provide an opportunity to receive a professional qualification as a nurse but also gain a Bachelor's degree in nursing. The aim of these projects is to demonstrate knowledge and understanding within the major field of the education. This study aimed to describe and analyze the topics as well as theoretical frameworks and concepts in nursing students' independent projects, which lead to a Bachelor's degree, in a Swedish context. A total of 491 independent projects, written by nursing students in Sweden, were included in the study. Topics together with theoretical frameworks and concepts in the projects were identified. Similar topics and theoretical frameworks and concepts, respectively, were grouped into subcategories, and similar subcategories were then merged into a main category. The number of entries in each category was counted for descriptive statistics in order to allow for the demonstration of magnitude. The most common topics concerned experiences and managing when having an illness, experiences of care and of being a caregiver, and healthcare staff's care and knowledge. The nursing theories/models that were most often used were Eriksson's Theory of Caritative Caring, Travelbee's Human-to-Human Relationship Model, and Orem's Self-care Theory. Among the non-nursing theories/models, perspectives and concepts lifeworld, ethical values and principles, existential concepts and quality of life/health-related quality of life, were most often used by these students. There may be some difficulty in finding a topic for the project that is relevant for both a professional qualification as a nurse, as well as for achieving the requirements of a Bachelor's degree in nursing. The study indicates that there is a need to widen the student's understanding of different nursing theories/perspectives/models/concepts during nursing education so that students are familiar with a broad range of these when conducting their

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

Directory of Open Access Journals (Sweden)

French Simon D

2012-04-01

Full Text Available Abstract 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

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

Science.gov (United States)

French, Simon D; Green, Sally E; O'Connor, Denise A; McKenzie, Joanne E; Francis, Jill J; Michie, Susan; Buchbinder, Rachelle; Schattner, Peter; Spike, Neil; Grimshaw, Jeremy M

2012-04-24

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. 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? 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. 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 framework to guide researchers through a

Measuring implementation behaviour of menu guidelines in the childcare setting: confirmatory factor analysis of a theoretical domains framework questionnaire (TDFQ).

Science.gov (United States)

Seward, Kirsty; Wolfenden, Luke; Wiggers, John; Finch, Meghan; Wyse, Rebecca; Oldmeadow, Christopher; Presseau, Justin; Clinton-McHarg, Tara; Yoong, Sze Lin

2017-04-04

While there are number of frameworks which focus on supporting the implementation of evidence based approaches, few psychometrically valid measures exist to assess constructs within these frameworks. This study aimed to develop and psychometrically assess a scale measuring each domain of the Theoretical Domains Framework for use in assessing the implementation of dietary guidelines within a non-health care setting (childcare services). A 75 item 14-domain Theoretical Domains Framework Questionnaire (TDFQ) was developed and administered via telephone interview to 202 centre based childcare service cooks who had a role in planning the service menu. Confirmatory factor analysis (CFA) was undertaken to assess the reliability, discriminant validity and goodness of fit of the 14-domain theoretical domain framework measure. For the CFA, five iterative processes of adjustment were undertaken where 14 items were removed, resulting in a final measure consisting of 14 domains and 61 items. For the final measure: the Chi-Square goodness of fit statistic was 3447.19; the Standardized Root Mean Square Residual (SRMR) was 0.070; the Root Mean Square Error of Approximation (RMSEA) was 0.072; and the Comparative Fit Index (CFI) had a value of 0.78. While only one of the three indices support goodness of fit of the measurement model tested, a 14-domain model with 61 items showed good discriminant validity and internally consistent items. Future research should aim to assess the psychometric properties of the developed TDFQ in other community-based settings.

A theoretical signal processing framework for linear diffusion MRI: Implications for parameter estimation and experiment design.

Science.gov (United States)

Varadarajan, Divya; Haldar, Justin P

2017-11-01

The data measured in diffusion MRI can be modeled as the Fourier transform of the Ensemble Average Propagator (EAP), a probability distribution that summarizes the molecular diffusion behavior of the spins within each voxel. This Fourier relationship is potentially advantageous because of the extensive theory that has been developed to characterize the sampling requirements, accuracy, and stability of linear Fourier reconstruction methods. However, existing diffusion MRI data sampling and signal estimation methods have largely been developed and tuned without the benefit of such theory, instead relying on approximations, intuition, and extensive empirical evaluation. This paper aims to address this discrepancy by introducing a novel theoretical signal processing framework for diffusion MRI. The new framework can be used to characterize arbitrary linear diffusion estimation methods with arbitrary q-space sampling, and can be used to theoretically evaluate and compare the accuracy, resolution, and noise-resilience of different data acquisition and parameter estimation techniques. The framework is based on the EAP, and makes very limited modeling assumptions. As a result, the approach can even provide new insight into the behavior of model-based linear diffusion estimation methods in contexts where the modeling assumptions are inaccurate. The practical usefulness of the proposed framework is illustrated using both simulated and real diffusion MRI data in applications such as choosing between different parameter estimation methods and choosing between different q-space sampling schemes. Copyright © 2017 Elsevier Inc. All rights reserved.

Rapid Gradient-Echo Imaging

Science.gov (United States)

Hargreaves, Brian

2012-01-01

Gradient echo sequences are widely used in magnetic resonance imaging (MRI) for numerous applications ranging from angiography to perfusion to functional MRI. Compared with spin-echo techniques, the very short repetition times of gradient-echo methods enable very rapid 2D and 3D imaging, but also lead to complicated “steady states.” Signal and contrast behavior can be described graphically and mathematically, and depends strongly on the type of spoiling: fully balanced (no spoiling), gradient spoiling, or RF-spoiling. These spoiling options trade off between high signal and pure T1 contrast while the flip angle also affects image contrast in all cases, both of which can be demonstrated theoretically and in image examples. As with spin-echo sequences, magnetization preparation can be added to gradient-echo sequences to alter image contrast. Gradient echo sequences are widely used for numerous applications such as 3D perfusion imaging, functional MRI, cardiac imaging and MR angiography. PMID:23097185

Theoretical model estimation of guest diffusion in Metal-Organic Frameworks (MOFs)

KAUST Repository

Zheng, Bin

2015-08-11

Characterizing molecule diffusion in nanoporous matrices is critical to understanding the novel chemical and physical properties of metal-organic frameworks (MOFs). In this paper, we developed a theoretical model to fastly and accurately compute the diffusion rate of guest molecules in a zeolitic imidazolate framework-8 (ZIF-8). The ideal gas or equilibrium solution diffusion model was modified to contain the effect of periodical media via introducing the possibility of guests passing through the framework gate. The only input in our model is the energy barrier of guests passing through the MOF’s gate. Molecular dynamics (MD) methods were employed to gather the guest density profile, which then was used to deduce the energy barrier values. This produced reliable results that require a simulation time of 5 picoseconds, which is much shorter when using pure MD methods (in the billisecond scale) . Also, we used density functional theory (DFT) methods to obtain the energy profile of guests passing through gates, as this does not require specification of a force field for the MOF degrees of freedom. In the DFT calculation, we only considered one gate of MOFs each time; as this greatly reduced the computational cost. Based on the obtained energy barrier values we computed the diffusion rate of alkane and alcohol in ZIF-8 using our model, which was in good agreement with experimental test results and the calculation values from standard MD model. Our model shows the advantage of obtaining accurate diffusion rates for guests in MOFs for a lower computational cost and shorter calculation time. Thus, our analytic model calculation is especially attractive for high-throughput computational screening of the dynamic performance of guests in a framework.

Spatially Different Tissue-Scale Diffusivity Shapes ANGUSTIFOLIA3 Gradient in Growing Leaves.

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Kawade, Kensuke; Tanimoto, Hirokazu; Horiguchi, Gorou; Tsukaya, Hirokazu

2017-09-05

The spatial gradient of signaling molecules is pivotal for establishing developmental patterns of multicellular organisms. It has long been proposed that these gradients could arise from the pure diffusion process of signaling molecules between cells, but whether this simplest mechanism establishes the formation of the tissue-scale gradient remains unclear. Plasmodesmata are unique channel structures in plants that connect neighboring cells for molecular transport. In this study, we measured cellular- and tissue-scale kinetics of molecular transport through plasmodesmata in Arabidopsis thaliana developing leaf primordia by fluorescence recovery assays. These trans-scale measurements revealed biophysical properties of diffusive molecular transport through plasmodesmata and revealed that the tissue-scale diffusivity, but not the cellular-scale diffusivity, is spatially different along the leaf proximal-to-distal axis. We found that the gradient in cell size along the developmental axis underlies this spatially different tissue-scale diffusivity. We then asked how this diffusion-based framework functions in establishing a signaling gradient of endogenous molecules. ANGUSTIFOLIA3 (AN3) is a transcriptional co-activator, and as we have shown here, it forms a long-range signaling gradient along the leaf proximal-to-distal axis to determine a cell-proliferation domain. By genetically engineering AN3 mobility, we assessed each contribution of cell-to-cell movement and tissue growth to the distribution of the AN3 gradient. We constructed a diffusion-based theoretical model using these quantitative data to analyze the AN3 gradient formation and demonstrated that it could be achieved solely by the diffusive molecular transport in a growing tissue. Our results indicate that the spatially different tissue-scale diffusivity is a core mechanism for AN3 gradient formation. This provides evidence that the pure diffusion process establishes the formation of the long-range signaling

Scaling of spectra in grid turbulence with a mean cross-stream temperature gradient

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Bahri, Carla; Arwatz, Gilad; Mueller, Michael E.; George, William K.; Hultmark, Marcus

2014-11-01

Scaling of grid turbulence with a constant mean cross-stream temperature gradient is investigated using a combination of theoretical predictions, DNS, and experimental data. Conditions for self-similarity of the governing equations and the scalar spectrum are investigated, which reveals necessary conditions for self-similarity to exist. These conditions provide a theoretical framework for scaling of the temperature spectrum as well as the temperature flux spectrum. One necessary condition, predicted by the theory, is that the characteristic length scale describing the scalar spectrum must vary as √{ t} for a self-similar solution to exist. In order to investigate this, T-NSTAP sensors, specially designed for temperature measurements at high frequencies, were deployed in a heated passive grid turbulence setup together with conventional cold-wires, and complementary DNS calculations were performed to complement and complete the experimental data. These data are used to compare the behavior of different length scales and validate the theoretical predictions.

Theoretical investigation on structural and electronic properties of PdO{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Viswanathan, E.; Sundareswari, M., E-mail: sund-uday@yahoo.co.in, E-mail: sundare65@gmail.com; Jayalakshmi, D. S.; Manjula, M. [Department of Physics, Sathyabama University, Jeppiaar Nagar, OMR, Chennai-600119 (India)

2015-06-24

Theoretical studies on rutile type Palladium Dioxide were carried out with the aim of analyzing structural and electronic properties at ambient condition using the first principle calculation based on density functional theory. Within the framework of density functional theory, we used full potential linearized augmented plane wave method(FP-LAPW) in Wien 2k code. The exchange and correlation effect is treated with generalized gradient approximation (GGA) using the Perdew, Burke and Eruzeroff form. The charge density plots, density of states and band structure are plotted and discussed.

Molecular gradient for second-order Møller-Plesset perturbation theory using the divide-expand-consolidate (DEC) scheme

DEFF Research Database (Denmark)

Kristensen, Kasper; Jørgensen, Poul; Jansik, Branislav

2012-01-01

We demonstrate that the divide-expand-consolidate (DEC) scheme – which has previously been used to determine the second-order Møller–Plesset (MP2) correlation energy – can be applied to evaluate the MP2 molecular gradient in a linear-scaling and embarrassingly parallel manner using a set of local......-box manner to ensure that the error in the DEC-MP2 correlation energy compared to a standard MP2 calculation is proportional to a single input threshold denoted the fragment optimization threshold (FOT). The FOT also implicitly controls the error in the DEC-MP2 molecular gradient as substantiated...... by a theoretical analysis and numerical results. The development of the DEC-MP2 molecular gradient is the initial step towards calculating higher order energy derivatives for large molecular systems using the DEC framework, both at the MP2 level of theory and for more accurate coupled-cluster methods....

Toward a Theoretical Framework for Studying Climate Change Policies: Insights from the Case Study of Singapore

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Ai Sian Ng

2017-07-01

Full Text Available The world decided in December 2015 to take actions to reduce global warming. To contribute toward this goal, this research examines possible policy levers for inclusion in the climate change ratification plan. A case study of the measures taken by the Republic of Singapore, a low-lying 719.2 km2 island without natural resources in Asia, is conducted. Being vulnerable to climate change impact and yet having to balance her people’s needs and economic progress with limited resources, the measures taken by this small country could offer policy insights for small states and states without access to alternative energy sources. This research analyzes the online policy documents posted by eleven organizations to answer the main research question of identifying policy levers as theoretical constructs to form a framework that can be used to study climate change policies. A qualitative data analysis software, QSR NVivo 10, is used to classify the proposed nodes developed by the researchers using a system perspective integrating the insights from the key international climate change frameworks with the theoretical concepts from the model of pro-environmental behavior. The findings can offer insights toward developing a new contextual influence framework, which can help strengthen policy development and outcome measurement.

Matching adherence interventions to patient determinants using the Theoretical Domains Framework

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Samuel Sebastian Allemann

2016-11-01

Full Text Available IntroductionDespite much research, interventions to improve medication adherence report disappointing and inconsistent results. Tailored approaches that match interventions and patient determinants of non-adherence were seldom used in clinical trials. The presence of a multitude of theoretical frameworks and models to categorize interventions and patient determinants complicated the development of common categories shared by interventions and determinants. We retrieved potential interventions and patient determinants from published literature on medication adherence, matched them like locks and keys, and categorized them according to the Theoretical Domains Framework (TDF.MethodsWe identified the most relevant literature reviews on interventions and determinants in a pragmatic literature search, extracted all interventions and determinants, grouped similar concepts to umbrella terms and assigned them to TDF categories. All steps were finalized in consensus discussion between the authors.ResultsSixteen articles (5 with determinants, 11 with interventions were included for analysis. We extracted 103 interventions and 42 determinants that we divided in 26 modifiable and 16 unmodifiable determinants. All interventions and modifiable determinants were matched within 11 categories (Knowledge; Skills; Social/professional role and identity; Beliefs about capabilities; Beliefs about consequences; Intentions; Memory, Attention and decision processes; Environmental context and resources; Social influences; Emotion; and Behavioral regulation.ConclusionIn published trials on medication adherence, the congruence between interventions and determinants can be assessed with matching interventions to determinants. To be successful, interventions in medication adherence should target current modifiable determinants and be tailored to the unmodifiable determinants. Modifiable and unmodifiable determinants need to be assessed at inclusion of intervention studies to

Matching Adherence Interventions to Patient Determinants Using the Theoretical Domains Framework.

Science.gov (United States)

Allemann, Samuel S; Nieuwlaat, Robby; van den Bemt, Bart J F; Hersberger, Kurt E; Arnet, Isabelle

2016-01-01

Introduction: Despite much research, interventions to improve medication adherence report disappointing and inconsistent results. Tailored approaches that match interventions and patient determinants of non-adherence were seldom used in clinical trials. The presence of a multitude of theoretical frameworks and models to categorize interventions and patient determinants complicated the development of common categories shared by interventions and determinants. We retrieved potential interventions and patient determinants from published literature on medication adherence, matched them like locks and keys, and categorized them according to the Theoretical Domains Framework (TDF). Methods: We identified the most relevant literature reviews on interventions and determinants in a pragmatic literature search, extracted all interventions and determinants, grouped similar concepts to umbrella terms and assigned them to TDF categories. All steps were finalized in consensus discussion between the authors. Results: Sixteen articles (5 with determinants, 11 with interventions) were included for analysis. We extracted 103 interventions and 42 determinants that we divided in 26 modifiable and 16 unmodifiable determinants. All interventions and modifiable determinants were matched within 11 categories (Knowledge; Skills; Social/professional role and identity; Beliefs about capabilities; Beliefs about consequences; Intentions; Memory, Attention and decision processes; Environmental context and resources; Social influences; Emotion; and Behavioral regulation). Conclusion: In published trials on medication adherence, the congruence between interventions and determinants can be assessed with matching interventions to determinants. To be successful, interventions in medication adherence should target current modifiable determinants and be tailored to the unmodifiable determinants. Modifiable and unmodifiable determinants need to be assessed at inclusion of intervention studies to

An algorithm for hyperspectral remote sensing of aerosols: 1. Development of theoretical framework

International Nuclear Information System (INIS)

Hou, Weizhen; Wang, Jun; Xu, Xiaoguang; Reid, Jeffrey S.; Han, Dong

2016-01-01

This paper describes the first part of a series of investigations to develop algorithms for simultaneous retrieval of aerosol parameters and surface reflectance from a newly developed hyperspectral instrument, the GEOstationary Trace gas and Aerosol Sensor Optimization (GEO-TASO), by taking full advantage of available hyperspectral measurement information in the visible bands. We describe the theoretical framework of an inversion algorithm for the hyperspectral remote sensing of the aerosol optical properties, in which major principal components (PCs) for surface reflectance is assumed known, and the spectrally dependent aerosol refractive indices are assumed to follow a power-law approximation with four unknown parameters (two for real and two for imaginary part of refractive index). New capabilities for computing the Jacobians of four Stokes parameters of reflected solar radiation at the top of the atmosphere with respect to these unknown aerosol parameters and the weighting coefficients for each PC of surface reflectance are added into the UNified Linearized Vector Radiative Transfer Model (UNL-VRTM), which in turn facilitates the optimization in the inversion process. Theoretical derivations of the formulas for these new capabilities are provided, and the analytical solutions of Jacobians are validated against the finite-difference calculations with relative error less than 0.2%. Finally, self-consistency check of the inversion algorithm is conducted for the idealized green-vegetation and rangeland surfaces that were spectrally characterized by the U.S. Geological Survey digital spectral library. It shows that the first six PCs can yield the reconstruction of spectral surface reflectance with errors less than 1%. Assuming that aerosol properties can be accurately characterized, the inversion yields a retrieval of hyperspectral surface reflectance with an uncertainty of 2% (and root-mean-square error of less than 0.003), which suggests self-consistency in the

Gradient descent for robust kernel-based regression

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Guo, Zheng-Chu; Hu, Ting; Shi, Lei

2018-06-01

In this paper, we study the gradient descent algorithm generated by a robust loss function over a reproducing kernel Hilbert space (RKHS). The loss function is defined by a windowing function G and a scale parameter σ, which can include a wide range of commonly used robust losses for regression. There is still a gap between theoretical analysis and optimization process of empirical risk minimization based on loss: the estimator needs to be global optimal in the theoretical analysis while the optimization method can not ensure the global optimality of its solutions. In this paper, we aim to fill this gap by developing a novel theoretical analysis on the performance of estimators generated by the gradient descent algorithm. We demonstrate that with an appropriately chosen scale parameter σ, the gradient update with early stopping rules can approximate the regression function. Our elegant error analysis can lead to convergence in the standard L 2 norm and the strong RKHS norm, both of which are optimal in the mini-max sense. We show that the scale parameter σ plays an important role in providing robustness as well as fast convergence. The numerical experiments implemented on synthetic examples and real data set also support our theoretical results.

On fracture in finite strain gradient plasticity

DEFF Research Database (Denmark)

Martínez Pañeda, Emilio; Niordson, Christian Frithiof

2016-01-01

In this work a general framework for damage and fracture assessment including the effect of strain gradients is provided. Both mechanism-based and phenomenological strain gradient plasticity (SGP) theories are implemented numerically using finite deformation theory and crack tip fields are invest......In this work a general framework for damage and fracture assessment including the effect of strain gradients is provided. Both mechanism-based and phenomenological strain gradient plasticity (SGP) theories are implemented numerically using finite deformation theory and crack tip fields...... are investigated. Differences and similarities between the two approaches within continuum SGP modeling are highlighted and discussed. Local strain hardening promoted by geometrically necessary dislocations (GNDs) in the vicinity of the crack leads to much higher stresses, relative to classical plasticity...... in the multiple parameter version of the phenomenological SGP theory. Since this also dominates the mechanics of indentation testing, results suggest that length parameters characteristic of mode I fracture should be inferred from nanoindentation....

Rehabilitation goal setting with community dwelling adults with acquired brain injury: a theoretical framework derived from clinicians' reflections on practice.

Science.gov (United States)

Prescott, Sarah; Fleming, Jennifer; Doig, Emmah

2017-06-11

The aim of this study was to explore clinicians' experiences of implementing goal setting with community dwelling clients with acquired brain injury, to develop a goal setting practice framework. Grounded theory methodology was employed. Clinicians, representing six disciplines across seven services, were recruited and interviewed until theoretical saturation was achieved. A total of 22 clinicians were interviewed. A theoretical framework was developed to explain how clinicians support clients to actively engage in goal setting in routine practice. The framework incorporates three phases: a needs identification phase, a goal operationalisation phase, and an intervention phase. Contextual factors, including personal and environmental influences, also affect how clinicians and clients engage in this process. Clinicians use additional strategies to support clients with impaired self-awareness. These include structured communication and metacognitive strategies to operationalise goals. For clients with emotional distress, clinicians provide additional time and intervention directed at new identity development. The goal setting practice framework may guide clinician's understanding of how to engage in client-centred goal setting in brain injury rehabilitation. There is a predilection towards a client-centred goal setting approach in the community setting, however, contextual factors can inhibit implementation of this approach. Implications for Rehabilitation The theoretical framework describes processes used to develop achievable client-centred goals with people with brain injury. Building rapport is a core strategy to engage clients with brain injury in goal setting. Clients with self-awareness impairment benefit from additional metacognitive strategies to participate in goal setting. Clients with emotional distress may need additional time for new identity development.

Chemical and morphological gradient scaffolds to mimic hierarchically complex tissues: From theoretical modeling to their fabrication.

Science.gov (United States)

Marrella, Alessandra; Aiello, Maurizio; Quarto, Rodolfo; Scaglione, Silvia

2016-10-01

Porous multiphase scaffolds have been proposed in different tissue engineering applications because of their potential to artificially recreate the heterogeneous structure of hierarchically complex tissues. Recently, graded scaffolds have been also realized, offering a continuum at the interface among different phases for an enhanced structural stability of the scaffold. However, their internal architecture is often obtained empirically and the architectural parameters rarely predetermined. The aim of this work is to offer a theoretical model as tool for the design and fabrication of functional and structural complex graded scaffolds with predicted morphological and chemical features, to overcome the time-consuming trial and error experimental method. This developed mathematical model uses laws of motions, Stokes equations, and viscosity laws to describe the dependence between centrifugation speed and fiber/particles sedimentation velocity over time, which finally affects the fiber packing, and thus the total porosity of the 3D scaffolds. The efficacy of the theoretical model was tested by realizing engineered graded grafts for osteochondral tissue engineering applications. The procedure, based on combined centrifugation and freeze-drying technique, was applied on both polycaprolactone (PCL) and collagen-type-I (COL) to test the versatility of the entire process. A functional gradient was combined to the morphological one by adding hydroxyapatite (HA) powders, to mimic the bone mineral phase. Results show that 3D bioactive morphologically and chemically graded grafts can be properly designed and realized in agreement with the theoretical model. Biotechnol. Bioeng. 2016;113: 2286-2297. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Geoscience Academic Provenance: A Theoretical Framework for Understanding Geoscience Students' Pathways

Science.gov (United States)

Houlton, H.; Keane, C.

2012-04-01

The demand and employment opportunities for geoscientists in the United States are projected to increase 23% from 2008 to 2018 (Gonzales, 2011). Despite this trend, there is a disconnect between undergraduate geoscience students and their desire to pursue geoscience careers. A theoretical framework was developed to understand the reasons why students decide to major in the geosciences and map those decisions to their career aspirations (Houlton, 2010). A modified critical incident study was conducted to develop the pathway model from 17, one-hour long semi-structured interviews of undergraduate geoscience majors from two Midwest Research Institutions (Houlton, 2010). Geoscience Academic Provenance maps geoscience students' initial interests, entry points into the major, critical incidents and future career goals as a pathway, which elucidates the relationships between each of these components. Analyses identified three geoscience student population groups that followed distinct pathways: Natives, Immigrants and Refugees. A follow up study was conducted in 2011 to ascertain whether these students continued on their predicted pathways, and if not, reasons for attrition. Geoscientists can use this framework as a guide to inform future recruitment and retention initiatives and target these geoscience population groups for specific employment sectors.

A Production Model for Construction: A Theoretical Framework

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Ricardo Antunes

2015-03-01

Full Text Available The building construction industry faces challenges, such as increasing project complexity and scope requirements, but shorter deadlines. Additionally, economic uncertainty and rising business competition with a subsequent decrease in profit margins for the industry demands the development of new approaches to construction management. However, the building construction sector relies on practices based on intuition and experience, overlooking the dynamics of its production system. Furthermore, researchers maintain that the construction industry has no history of the application of mathematical approaches to model and manage production. Much work has been carried out on how manufacturing practices apply to construction projects, mostly lean principles. Nevertheless, there has been little research to understand the fundamental mechanisms of production in construction. This study develops an in-depth literature review to examine the existing knowledge about production models and their characteristics in order to establish a foundation for dynamic production systems management in construction. As a result, a theoretical framework is proposed, which will be instrumental in the future development of mathematical production models aimed at predicting the performance and behaviour of dynamic project-based systems in construction.

Understanding, Selecting, and Integrating a Theoretical Framework in Dissertation Research: Creating the Blueprint for Your "House"

Science.gov (United States)

Grant, Cynthia; Osanloo, Azadeh

2014-01-01

The theoretical framework is one of the most important aspects in the research process, yet is often misunderstood by doctoral candidates as they prepare their dissertation research study. The importance of theory-driven thinking and acting is emphasized in relation to the selection of a topic, the development of research questions, the…

Near field plasmonic gradient effects on high vacuum tip-enhanced Raman spectroscopy.

Science.gov (United States)

Fang, Yurui; Zhang, Zhenglong; Chen, Li; Sun, Mengtao

2015-01-14

Near field gradient effects in high vacuum tip-enhanced Raman spectroscopy (HV-TERS) are a recent developing ultra-sensitive optical and spectral analysis technology on the nanoscale, based on the plasmons and plasmonic gradient enhancement in the near field and under high vacuum. HV-TERS can not only be used to detect ultra-sensitive Raman spectra enhanced by surface plasmon, but also to detect clear molecular IR-active modes enhanced by strongly plasmonic gradient. Furthermore, the molecular overtone modes and combinational modes can also be experimentally measured, where the Fermi resonance and Darling-Dennison resonance were successfully observed in HV-TERS. Theoretical calculations using electromagnetic field theory firmly supported experimental observation. The intensity ratio of the plasmon gradient term over the linear plasmon term can reach values greater than 1. Theoretical calculations also revealed that with the increase in gap distance between tip and substrate, the decrease in the plasmon gradient was more significant than the decrease in plasmon intensity, which is the reason that the gradient Raman can be only observed in the near field. Recent experimental results of near field gradient effects on HV-TERS were summarized, following the section of the theoretical analysis.

Experiences of using the Theoretical Domains Framework across diverse clinical environments: a qualitative study

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Phillips CJ

2015-03-01

Framework (TDF is an integrative framework developed from a synthesis of psychological theories as a vehicle to help apply theoretical approaches to interventions aimed at behavior change. Purpose: This study explores experiences of TDF use by professionals from multiple disciplines across diverse clinical settings. Methods: Mixed methods were used to examine experiences, attitudes, and perspectives of health professionals in using the TDF in health care implementation projects. Individual interviews were conducted with ten health care professionals from six disciplines who used the TDF in implementation projects. Deductive content and thematic analysis were used. Results: Three main themes and associated subthemes were identified including: 1 reasons for use of the TDF (increased confidence, broader perspective, and theoretical underpinnings; 2 challenges using the TDF (time and resources, operationalization of the TDF and; 3 future use of the TDF. Conclusion: The TDF provided a useful, flexible framework for a diverse group of health professionals working across different clinical settings for the assessment of barriers and targeting resources to influence behavior change for implementation projects. The development of practical tools and training or support is likely to aid the utility of TDF. Keywords: barriers and enablers, behavioral change, evidence-based practice, implementation, health care, Theoretical Domains Framework

Goal setting and action planning in the rehabilitation setting: development of a theoretically informed practice framework.

Science.gov (United States)

Scobbie, Lesley; Dixon, Diane; Wyke, Sally

2011-05-01

Setting and achieving goals is fundamental to rehabilitation practice but has been criticized for being a-theoretical and the key components of replicable goal-setting interventions are not well established. To describe the development of a theory-based goal setting practice framework for use in rehabilitation settings and to detail its component parts. Causal modelling was used to map theories of behaviour change onto the process of setting and achieving rehabilitation goals, and to suggest the mechanisms through which patient outcomes are likely to be affected. A multidisciplinary task group developed the causal model into a practice framework for use in rehabilitation settings through iterative discussion and implementation with six patients. Four components of a goal-setting and action-planning practice framework were identified: (i) goal negotiation, (ii) goal identification, (iii) planning, and (iv) appraisal and feedback. The variables hypothesized to effect change in patient outcomes were self-efficacy and action plan attainment. A theory-based goal setting practice framework for use in rehabilitation settings is described. The framework requires further development and systematic evaluation in a range of rehabilitation settings.

Theoretical framework and methodological development of common subjective health outcome measures in osteoarthritis: a critical review

Directory of Open Access Journals (Sweden)

Johnston Marie

2007-03-01

Full Text Available Abstract Subjective measures involving clinician ratings or patient self-assessments have become recognised as an important tool for the assessment of health outcome. The value of a health outcome measure is usually assessed by a psychometric evaluation of its reliability, validity and responsiveness. However, psychometric testing involves an accumulation of evidence and has recognised limitations. It has been suggested that an evaluation of how well a measure has been developed would be a useful additional criteria in assessing the value of a measure. This paper explored the theoretical background and methodological development of subjective health status measures commonly used in osteoarthritis research. Fourteen subjective health outcome measures commonly used in osteoarthritis research were examined. Each measure was explored on the basis of their i theoretical framework (was there a definition of what was being assessed and was it part of a theoretical model? and ii methodological development (what was the scaling strategy, how were the items generated and reduced, what was the response format and what was the scoring method?. Only the AIMS, SF-36 and WHOQOL defined what they were assessing (i.e. the construct of interest and no measure assessed was part of a theoretical model. None of the clinician report measures appeared to have implemented a scaling procedure or described the rationale for the items selected or scoring system. Of the patient self-report measures, the AIMS, MPQ, OXFORD, SF-36, WHOQOL and WOMAC appeared to follow a standard psychometric scaling method. The DRP and EuroQol used alternative scaling methods. The review highlighted the general lack of theoretical framework for both clinician report and patient self-report measures. This review also drew attention to the wide variation in the methodological development of commonly used measures in OA. While, in general the patient self-report measures had good methodological

Magnetoelectric Transverse Gradient Sensor with High Detection Sensitivity and Low Gradient Noise.

Science.gov (United States)

Zhang, Mingji; Or, Siu Wing

2017-10-25

We report, theoretically and experimentally, the realization of a high detection performance in a novel magnetoelectric (ME) transverse gradient sensor based on the large ME effect and the magnetic field gradient (MFG) technique in a pair of magnetically-biased, electrically-shielded, and mechanically-enclosed ME composites having a transverse orientation and an axial separation. The output voltage of the gradient sensor is directly obtained from the transverse MFG-induced difference in ME voltage between the two ME composites and is calibrated against transverse MFGs to give a high detection sensitivity of 0.4-30.6 V/(T/m), a strong common-mode magnetic field noise rejection rate of gradient noise of 0.16-620 nT/m/ Hz in a broad frequency range of 1 Hz-170 kHz under a small baseline of 35 mm. An analysis of experimental gradient noise spectra obtained in a magnetically-unshielded laboratory environment reveals the domination of the pink (1/ f ) noise, dielectric loss noise, and power-frequency noise below 3 kHz, in addition to the circuit noise above 3 kHz, in the gradient sensor. The high detection performance, together with the added merit of passive and direct ME conversion by the large ME effect in the ME composites, makes the gradient sensor suitable for the passive, direct, and broadband detection of transverse MFGs.

A Framework for the Corporate Governance of Data – Theoretical Background and Empirical Evidence

OpenAIRE

Tomi Dahlberg; Tiina Nokkala

2015-01-01

In a modern organization, IT and digital data have transformed from being functional resources to integral elements of business strategy. Against this background, our article addresses corporate governance of digital data in general and that of aging societies in particular. To describe the role of executives and managers in data governance, we first review the corporate and IT governance literature. We then propose a theoretical framework for the governance of data: a novel construct. We app...

Theoretically informed correlates of hepatitis B knowledge among four Asian groups: the health behavior framework.

Science.gov (United States)

Maxwell, Annette E; Stewart, Susan L; Glenn, Beth A; Wong, Weng Kee; Yasui, Yutaka; Chang, L Cindy; Taylor, Victoria M; Nguyen, Tung T; Chen, Moon S; Bastani, Roshan

2012-01-01

Few studies have examined theoretically informed constructs related to hepatitis B (HBV) testing, and comparisons across studies are challenging due to lack of uniformity in constructs assessed. The present analysis examined relationships among Health Behavior Framework factors across four Asian American groups to advance the development of theory-based interventions for HBV testing in at-risk populations. Data were collected from 2007-2010 as part of baseline surveys during four intervention trials promoting HBV testing among Vietnamese-, Hmong-, Korean- and Cambodian-Americans (n = 1,735). Health Behavior Framework constructs assessed included: awareness of HBV, knowledge of transmission routes, perceived susceptibility, perceived severity, doctor recommendation, stigma of HBV infection, and perceived efficacy of testing. Within each group we assessed associations between our intermediate outcome of knowledge of HBV transmission and other constructs, to assess the concurrent validity of our model and instruments. While the absolute levels for Health Behavior Framework factors varied across groups, relationships between knowledge and other factors were generally consistent. This suggests similarities rather than differences with respect to posited drivers of HBV-related behavior. Our findings indicate that Health Behavior Framework constructs are applicable to diverse ethnic groups and provide preliminary evidence for the construct validity of the Health Behavior Framework.

What is This Thing Called Sensemaking?: A Theoretical Framework for How Physics Students Resolve Inconsistencies in Understanding

Science.gov (United States)

Odden, Tor Ole B.

Students often emerge from introductory physics courses with a feeling that the concepts they have learned do not make sense. In recent years, science education researchers have begun to attend to this type of problem by studying the ways in which students make sense of science concepts. However, although many researchers agree intuitively on what sensemaking looks like, the literature on sensemaking is both theoretically fragmented and provides few guidelines for how to encourage and support the process. In this dissertation, I address this challenge by proposing a theoretical framework to describe students' sensemaking processes. I base this framework both on the science education research literature on sensemaking and on a series of video-recorded cognitive, clinical interviews conducted with introductory physics students enrolled in a course on electricity and magnetism. Using the science education research literature on sensemaking as well as a cognitivist, dynamic network model of mind as a theoretical lens, I first propose a coherent definition of sensemaking. Then, using this definition I analyze the sensemaking processes of these introductory physics students during episodes when they work to articulate and resolve gaps or inconsistencies in their understanding. Based on the students' framing, gestures, and dialogue I argue that the process of sensemaking unfolds in a distinct way, which we can describe as an epistemic game in which students first build a framework of knowledge, then identify a gap or inconsistency in that framework, iteratively build an explanation to resolve the gap or inconsistency, and (sometimes) successfully resolve it. I further argue that their entry into the sensemaking frame is facilitated by a specific question, which is in turn motivated by a gap or inconsistency in knowledge that I call the vexation point. I also investigate the results of sensemaking, arguing that students may use the technique of conceptual blending to both

Gradient pre-emphasis to counteract first-order concomitant fields on asymmetric MRI gradient systems.

Science.gov (United States)

Tao, Shengzhen; Weavers, Paul T; Trzasko, Joshua D; Shu, Yunhong; Huston, John; Lee, Seung-Kyun; Frigo, Louis M; Bernstein, Matt A

2017-06-01

To develop a gradient pre-emphasis scheme that prospectively counteracts the effects of the first-order concomitant fields for any arbitrary gradient waveform played on asymmetric gradient systems, and to demonstrate the effectiveness of this approach using a real-time implementation on a compact gradient system. After reviewing the first-order concomitant fields that are present on asymmetric gradients, we developed a generalized gradient pre-emphasis model assuming arbitrary gradient waveforms to counteract their effects. A numerically straightforward, easily implemented approximate solution to this pre-emphasis problem was derived that was compatible with the current hardware infrastructure of conventional MRI scanners for eddy current compensation. The proposed method was implemented on the gradient driver subsystem, and its real-time use was tested using a series of phantom and in vivo data acquired from two-dimensional Cartesian phase-difference, echo-planar imaging, and spiral acquisitions. The phantom and in vivo results demonstrated that unless accounted for, first-order concomitant fields introduce considerable phase estimation error into the measured data and result in images with spatially dependent blurring/distortion. The resulting artifacts were effectively prevented using the proposed gradient pre-emphasis. We have developed an efficient and effective gradient pre-emphasis framework to counteract the effects of first-order concomitant fields of asymmetric gradient systems. Magn Reson Med 77:2250-2262, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

Coherent evolution of parahydrogen induced polarisation using laser pump, NMR probe spectroscopy: Theoretical framework and experimental observation.

Science.gov (United States)

Halse, Meghan E; Procacci, Barbara; Henshaw, Sarah-Louise; Perutz, Robin N; Duckett, Simon B

2017-05-01

We recently reported a pump-probe method that uses a single laser pulse to introduce parahydrogen (p-H 2 ) into a metal dihydride complex and then follows the time-evolution of the p-H 2 -derived nuclear spin states by NMR. We present here a theoretical framework to describe the oscillatory behaviour of the resultant hyperpolarised NMR signals using a product operator formalism. We consider the cases where the p-H 2 -derived protons form part of an AX, AXY, AXYZ or AA'XX' spin system in the product molecule. We use this framework to predict the patterns for 2D pump-probe NMR spectra, where the indirect dimension represents the evolution during the pump-probe delay and the positions of the cross-peaks depend on the difference in chemical shift of the p-H 2 -derived protons and the difference in their couplings to other nuclei. The evolution of the NMR signals of the p-H 2 -derived protons, as well as the transfer of hyperpolarisation to other NMR-active nuclei in the product, is described. The theoretical framework is tested experimentally for a set of ruthenium dihydride complexes representing the different spin systems. Theoretical predictions and experimental results agree to within experimental error for all features of the hyperpolarised 1 H and 31 P pump-probe NMR spectra. Thus we establish the laser pump, NMR probe approach as a robust way to directly observe and quantitatively analyse the coherent evolution of p-H 2 -derived spin order over micro-to-millisecond timescales. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

A theoretical framework for negotiating the path of emergency management multi-agency coordination.

Science.gov (United States)

Curnin, Steven; Owen, Christine; Paton, Douglas; Brooks, Benjamin

2015-03-01

Multi-agency coordination represents a significant challenge in emergency management. The need for liaison officers working in strategic level emergency operations centres to play organizational boundary spanning roles within multi-agency coordination arrangements that are enacted in complex and dynamic emergency response scenarios creates significant research and practical challenges. The aim of the paper is to address a gap in the literature regarding the concept of multi-agency coordination from a human-environment interaction perspective. We present a theoretical framework for facilitating multi-agency coordination in emergency management that is grounded in human factors and ergonomics using the methodology of core-task analysis. As a result we believe the framework will enable liaison officers to cope more efficiently within the work domain. In addition, we provide suggestions for extending the theory of core-task analysis to an alternate high reliability environment. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Trophic interaction modifications: an empirical and theoretical framework.

Science.gov (United States)

Terry, J Christopher D; Morris, Rebecca J; Bonsall, Michael B

2017-10-01

Consumer-resource interactions are often influenced by other species in the community. At present these 'trophic interaction modifications' are rarely included in ecological models despite demonstrations that they can drive system dynamics. Here, we advocate and extend an approach that has the potential to unite and represent this key group of non-trophic interactions by emphasising the change to trophic interactions induced by modifying species. We highlight the opportunities this approach brings in comparison to frameworks that coerce trophic interaction modifications into pairwise relationships. To establish common frames of reference and explore the value of the approach, we set out a range of metrics for the 'strength' of an interaction modification which incorporate increasing levels of contextual information about the system. Through demonstrations in three-species model systems, we establish that these metrics capture complimentary aspects of interaction modifications. We show how the approach can be used in a range of empirical contexts; we identify as specific gaps in current understanding experiments with multiple levels of modifier species and the distributions of modifications in networks. The trophic interaction modification approach we propose can motivate and unite empirical and theoretical studies of system dynamics, providing a route to confront ecological complexity. © 2017 The Authors. Ecology Letters published by CNRS and John Wiley & Sons Ltd.

Patients' perceptions and experiences of cardiovascular disease and diabetes prevention programmes: A systematic review and framework synthesis using the Theoretical Domains Framework.

Science.gov (United States)

Shaw, Rachel L; Holland, Carol; Pattison, Helen M; Cooke, Richard

2016-05-01

This review provides a worked example of 'best fit' framework synthesis using the Theoretical Domains Framework (TDF) of health psychology theories as an a priori framework in the synthesis of qualitative evidence. Framework synthesis works best with 'policy urgent' questions. The review question selected was: what are patients' experiences of prevention programmes for cardiovascular disease (CVD) and diabetes? The significance of these conditions is clear: CVD claims more deaths worldwide than any other; diabetes is a risk factor for CVD and leading cause of death. A systematic review and framework synthesis were conducted. This novel method for synthesizing qualitative evidence aims to make health psychology theory accessible to implementation science and advance the application of qualitative research findings in evidence-based healthcare. Findings from 14 original studies were coded deductively into the TDF and subsequently an inductive thematic analysis was conducted. Synthesized findings produced six themes relating to: knowledge, beliefs, cues to (in)action, social influences, role and identity, and context. A conceptual model was generated illustrating combinations of factors that produce cues to (in)action. This model demonstrated interrelationships between individual (beliefs and knowledge) and societal (social influences, role and identity, context) factors. Several intervention points were highlighted where factors could be manipulated to produce favourable cues to action. However, a lack of transparency of behavioural components of published interventions needs to be corrected and further evaluations of acceptability in relation to patient experience are required. Further work is needed to test the comprehensiveness of the TDF as an a priori framework for 'policy urgent' questions using 'best fit' framework synthesis. Copyright © 2016 Elsevier Ltd. All rights reserved.

Parental coping in the context of having a child who is facing death: A theoretical framework.

Science.gov (United States)

Darlington, Anne-Sophie E; Korones, David N; Norton, Sally A

2017-07-13

While improvements in healthcare have resulted in children with complex and life-threatening conditions living longer, a proportion of them still die. The death of a child puts parents at increased risk for anxiety, depression, and complicated grief. Increasing our understanding of the coping strategies that parents use under such extreme circumstances will enable us to best provide support to families, before and after a child's death. Our aim herein was to develop a theoretical framework of parental coping. Evidence from the literature was employed to develop a theoretical framework to describe parental coping in the context of having a child with a life-limiting illness who is declining and facing eventual death. The reasoning and argument consists of three guiding elements: (1) the importance of approach as well as avoidance (as coping strategies) in the context of managing the extreme emotions; (2) the importance of the social aspect of coping within a family, whereby parents cope for others as well as for themselves; and (3) the importance of a flexible and balanced coping profile, with parents using different coping strategies simultaneously. Central to the proposed framework is that effective coping, in terms of adjustment, is achieved by balancing coping strategies: accessing different coping strategies simultaneously or in parallel with a specific focus on (1) approach and avoidance and (2) coping aimed at self and others. Understanding of parental coping strategies is essential for health professionals in order to support parents effectively.

The interrogation decision-making model: A general theoretical framework for confessions.

Science.gov (United States)

Yang, Yueran; Guyll, Max; Madon, Stephanie

2017-02-01

This article presents a new model of confessions referred to as the interrogation decision-making model . This model provides a theoretical umbrella with which to understand and analyze suspects' decisions to deny or confess guilt in the context of a custodial interrogation. The model draws upon expected utility theory to propose a mathematical account of the psychological mechanisms that not only underlie suspects' decisions to deny or confess guilt at any specific point during an interrogation, but also how confession decisions can change over time. Findings from the extant literature pertaining to confessions are considered to demonstrate how the model offers a comprehensive and integrative framework for organizing a range of effects within a limited set of model parameters. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Microhabitat amelioration and reduced competition among understorey plants as drivers of facilitation across environmental gradients: towards a unifying framework

Science.gov (United States)

Soliveres, Santiago; Eldridge, David J.; Maestre, Fernando T.; Bowker, Matthew A.; Tighe, Matthew; Escudero, Adrián

2015-01-01

Studies of facilitative interactions as drivers of plant richness along environmental gradients often assume the existence of an overarching stress gradient equally affecting the performance of all the species in a given community. However, co-existing species differ in their ecophysiological adaptations, and do not experience the same stress level under particular environmental conditions. Moreover, these studies assume a unimodal richness-biomass curve, which is not as general as previously thought. We ignored these assumptions to assess changes in plant-plant interactions, and their effect on local species richness, across environmental gradients in semi-arid areas of Spain and Australia. We aimed to understand the relative importance of direct (microhabitat amelioration) and indirect (changes in the competitive relationships among the understorey species: niche segregation, competitive exclusion or intransitivity) mechanisms that might underlie the effects of nurse plants on local species richness. By jointly studying these direct and indirect mechanisms using a unifying framework, we were able to see how our nurse plants (trees, shrubs and tussock grasses) not only increased local richness by expanding the niche of neighbouring species, but also by increasing niche segregation among them, though the latter was not important in all cases. The outcome of the competition-facilitation continuum changed depending on the study area, likely because the different types of stress gradient considered. When driven by both rainfall and temperature, or rainfall alone, the community-wide importance of nurse plants remained constant (Spanish sites), or showed a unimodal relationship along the gradient (Australian sites). This study expands our understanding of the relative roles of plant-plant interactions and environmental conditions as drivers of local species richness in semi-arid environments. These results can also be used to refine predictions about the response of

Microhabitat amelioration and reduced competition among understorey plants as drivers of facilitation across environmental gradients: towards a unifying framework.

Science.gov (United States)

Soliveres, Santiago; Eldridge, David J; Maestre, Fernando T; Bowker, Matthew A; Tighe, Matthew; Escudero, Adrián

2011-11-20

Studies of facilitative interactions as drivers of plant richness along environmental gradients often assume the existence of an overarching stress gradient equally affecting the performance of all the species in a given community. However, co-existing species differ in their ecophysiological adaptations, and do not experience the same stress level under particular environmental conditions. Moreover, these studies assume a unimodal richness-biomass curve, which is not as general as previously thought. We ignored these assumptions to assess changes in plant-plant interactions, and their effect on local species richness, across environmental gradients in semi-arid areas of Spain and Australia. We aimed to understand the relative importance of direct (microhabitat amelioration) and indirect (changes in the competitive relationships among the understorey species: niche segregation, competitive exclusion or intransitivity) mechanisms that might underlie the effects of nurse plants on local species richness. By jointly studying these direct and indirect mechanisms using a unifying framework, we were able to see how our nurse plants (trees, shrubs and tussock grasses) not only increased local richness by expanding the niche of neighbouring species, but also by increasing niche segregation among them, though the latter was not important in all cases. The outcome of the competition-facilitation continuum changed depending on the study area, likely because the different types of stress gradient considered. When driven by both rainfall and temperature, or rainfall alone, the community-wide importance of nurse plants remained constant (Spanish sites), or showed a unimodal relationship along the gradient (Australian sites). This study expands our understanding of the relative roles of plant-plant interactions and environmental conditions as drivers of local species richness in semi-arid environments. These results can also be used to refine predictions about the response of

Exploring Occupational and Behavioral Risk Factors for Obesity in Firefighters: A Theoretical Framework and Study Design

Directory of Open Access Journals (Sweden)

BongKyoo Choi

2011-12-01

Full Text Available Firefighters and police officers have the third highest prevalence of obesity among 41 male occupational groups in the United States (US. However, few studies have examined the relationship of firefighter working conditions and health behaviors with obesity. This paper presents a theoretical framework describing the relationship between working conditions, health behaviors, and obesity in firefighters. In addition, the paper describes a detailed study plan for exploring the role of occupational and behavioral risk factors in the development of obesity in firefighters enrolled in the Orange County Fire Authority Wellness Fitness Program. The study plan will be described with emphasis on its methodological merits: adopting a participatory action research approach, developing a firefighter-specific work and health questionnaire, conducting both a cross-sectional epidemiological study using the questionnaire and a sub-study to assess the validity of the questionnaire with dietary intake and physical activity measures, and evaluating the strengths and weaknesses of the body mass index as an obesity measure in comparison to skinfold-based percent body fat. The study plan based on a theoretical framework can be an essential first step for establishing effective intervention programs for obesity among professional and voluntary firefighters.

A Game-theoretic Framework for Network Coding Based Device-to-Device Communications

KAUST Repository

Douik, Ahmed S.; Sorour, Sameh; Tembine, Hamidou; Al-Naffouri, Tareq Y.; Alouini, Mohamed-Slim

2016-01-01

This paper investigates the delay minimization problem for instantly decodable network coding (IDNC) based deviceto- device (D2D) communications. In D2D enabled systems, users cooperate to recover all their missing packets. The paper proposes a game theoretic framework as a tool for improving the distributed solution by overcoming the need for a central controller or additional signaling in the system. The session is modeled by self-interested players in a non-cooperative potential game. The utility functions are designed so as increasing individual payoff results in a collective behavior achieving both a desirable system performance in a shared network environment and the Nash equilibrium. Three games are developed whose first reduces the completion time, the second the maximum decoding delay and the third the sum decoding delay. The paper, further, improves the formulations by including a punishment policy upon collision occurrence so as to achieve the Nash bargaining solution. Learning algorithms are proposed for systems with complete and incomplete information, and for the imperfect feedback scenario. Numerical results suggest that the proposed game-theoretical formulation provides appreciable performance gain against the conventional point-to-multipoint (PMP), especially for reliable user-to-user channels.

A Game-theoretic Framework for Network Coding Based Device-to-Device Communications

KAUST Repository

Douik, Ahmed

2016-06-29

This paper investigates the delay minimization problem for instantly decodable network coding (IDNC) based deviceto- device (D2D) communications. In D2D enabled systems, users cooperate to recover all their missing packets. The paper proposes a game theoretic framework as a tool for improving the distributed solution by overcoming the need for a central controller or additional signaling in the system. The session is modeled by self-interested players in a non-cooperative potential game. The utility functions are designed so as increasing individual payoff results in a collective behavior achieving both a desirable system performance in a shared network environment and the Nash equilibrium. Three games are developed whose first reduces the completion time, the second the maximum decoding delay and the third the sum decoding delay. The paper, further, improves the formulations by including a punishment policy upon collision occurrence so as to achieve the Nash bargaining solution. Learning algorithms are proposed for systems with complete and incomplete information, and for the imperfect feedback scenario. Numerical results suggest that the proposed game-theoretical formulation provides appreciable performance gain against the conventional point-to-multipoint (PMP), especially for reliable user-to-user channels.

Urban activism in Central and Eastern Europe: A theoretical framework

Directory of Open Access Journals (Sweden)

Alexandra Bitušíková

2015-12-01

Full Text Available The study brings an overview of selected transdisciplinary theoretical approaches to the study of urban movements and activism placed within the framework of civil society and social movements, focused on the region of Central and Eastern Europe, and seen from a social anthropological perspective. It attempts to challenge older academic writings that described civil society in Central and Eastern Europe as underdeveloped and weak, and presents research that points out a specific nature of activism in the countries of the region. It builds primarily on the concepts of civil society, social movements, urban movements and urban activism as presented by scholars both from “Western” and “Central and Eastern” European countries and demonstrates that after more than two decades since the fall of communism it is still important to take different historic, political, economic, social and cultural contexts into account when comparing urban movements and activism within Europe.

A Theoretical Framework for Association Studies in F2 Family Pools Using Allele Frequencies from Genotyping-By-Sequencing

DEFF Research Database (Denmark)

Janss, Luc L; Ashraf, Bilal H; Greve-Pedersen, Morten

a sequencing approach to obtain Single Nucleotide Polymorphisms (SNPs) frequencies is considered here. In this work we develop the theoretical framework to perform association studies using allele frequencies from such F2 family pools. We show that expected allele frequencies in the F2 families will have...

A conceptual framework to represent the theoretical domain of “innovation capability” in organizations

Directory of Open Access Journals (Sweden)

Ramon B. Narcizo

2017-01-01

Full Text Available The term ‘innovation capability’ has been used recurrently in the innovation literature, but there is still considerable divergence about its meaning and implication to organizations. A consensus exists that, to innovate, organizations must possess innovation capability, and that the ownership of this feature is not a binary process, but rather an evolutionary level process. This evolutionary logic is analogous to the basic structure of organizational maturity models. However, the literature integrating innovation capability into a maturity perspective is still limited. Considering these premises, from a broad bibliographical research, this article presents a framework of reference to represent the entire theoretical domain of innovation capability. Its purpose is to classify the main types of models about this construct available in the reference literature. It is organized at increasing levels of complexity, so that each level creates the conceptual conditions for the construction of more comprehensive models. Similar to the main use cases for maturity models, there are three basic levels for the framework: descriptive; comparative; and, finally, prescriptive models of innovation capability. Considering this cumulative framework, the authors argue that, to be fully understood, innovation capability should be studied using the perspective of maturity models.

A strain gradient plasticity theory with application to wire torsion

KAUST Repository

Liu, J. X.; El Sayed, Tamer S.

2014-01-01

Based on the framework of the existing strain gradient plasticity theories, we have examined three kinds of relations for the plastic strain dependence of the material intrinsic length scale, and thus developed updated strain gradient plasticity

Bridging Thermal Infrared Sensing and Physically-Based Evapotranspiration Modeling: From Theoretical Implementation to Validation Across an Aridity Gradient in Australian Ecosystems

DEFF Research Database (Denmark)

Mallick, Kaniska; Toivonen, Erika; Trebs, Ivonne

2018-01-01

model, the Surface Temperature Initiated Closure (STIC1.2), that physically integrates TR observations into a combined Penman‐Monteith Shuttleworth‐Wallace (PM‐SW) framework for directly estimating E, and overcoming the uncertainties associated with T0 and gA determination. An evaluation of STIC1.......2 against high temporal frequency SEB flux measurements across an aridity gradient in Australia revealed a systematic error of 10% – 52% in E from mesic to arid ecosystem, and low systematic error in sensible heat fluxes (H) (12% – 25%) in all ecosystems. Uncertainty in TR versus moisture availability...

Beyond the SCS-CN method: A theoretical framework for spatially lumped rainfall-runoff response

Science.gov (United States)

Bartlett, M. S.; Parolari, A. J.; McDonnell, J. J.; Porporato, A.

2016-06-01

Since its introduction in 1954, the Soil Conservation Service curve number (SCS-CN) method has become the standard tool, in practice, for estimating an event-based rainfall-runoff response. However, because of its empirical origins, the SCS-CN method is restricted to certain geographic regions and land use types. Moreover, it does not describe the spatial variability of runoff. To move beyond these limitations, we present a new theoretical framework for spatially lumped, event-based rainfall-runoff modeling. In this framework, we describe the spatially lumped runoff model as a point description of runoff that is upscaled to a watershed area based on probability distributions that are representative of watershed heterogeneities. The framework accommodates different runoff concepts and distributions of heterogeneities, and in doing so, it provides an implicit spatial description of runoff variability. Heterogeneity in storage capacity and soil moisture are the basis for upscaling a point runoff response and linking ecohydrological processes to runoff modeling. For the framework, we consider two different runoff responses for fractions of the watershed area: "prethreshold" and "threshold-excess" runoff. These occur before and after infiltration exceeds a storage capacity threshold. Our application of the framework results in a new model (called SCS-CNx) that extends the SCS-CN method with the prethreshold and threshold-excess runoff mechanisms and an implicit spatial description of runoff. We show proof of concept in four forested watersheds and further that the resulting model may better represent geographic regions and site types that previously have been beyond the scope of the traditional SCS-CN method.

Life in the salinity gradient: Discovering mechanisms behind a new biodiversity pattern

Science.gov (United States)

Telesh, Irena; Schubert, Hendrik; Skarlato, Sergei

2013-12-01

A recently discovered paradoxical maximum of planktonic protistan species in the salinity gradient of the Baltic Sea revealed an inverse trend of species number/salinity relation in comparison to the previously accepted species-minimum model for macrozoobenthos. Here, we review long-term data on organisms of different size classes and ecological groups to show that eukaryotic and prokaryotic microbes in plankton demonstrate a maximum species richness in the challenging zone of the critical salinity 5-8, where the large-bodied bottom dwellers (macrozoobenthos, macroalgae and aquatic higher plants) experience large-scale salinity stress which leads to an impoverished diversity. We propose a new conceptual model to explain why the diversity of small, fast-developing, rapidly evolving unicellular plankton organisms benefits from relative vacancy of brackish-water ecological niches and impaired competitiveness therein. The ecotone theory, Hutchinson's Ecological Niche Concept, species-area relationships and the Intermediate Disturbance Hypothesis are considered as a theoretical framework for understanding extinctions, speciation and variations in the evolution rates of different aquatic species in ecosystems with the pronounced salinity gradient.

Theoretical Framework and Model Design for Beautiful Countryside Construction in China

Directory of Open Access Journals (Sweden)

ZHENG Xiang-qun

2015-04-01

Full Text Available In the context of China today, the process of beautiful countryside construction mainly imitates the patterns of‘urbanization’construction. However, this approach leads to the loss of countryside characteristics and the separation of agricultural culture. Therefore, it's urgent to carry out research of the theoretical framework and model design for beautiful countryside construction. In this paper, based on the analysis of the beautiful countryside construction connotation, the basic theory of beautiful countryside construction was summarized in three aspects: rural complex ecosystem model, multi-functionality of rural model and sustainable development evaluation model. The basic idea of the beautiful countryside construction mode was studied. The design method of beautiful countryside construction mode was proposed in three levels: planning, scheming and evaluating. The research results might offer scientific reference for improving the scientific and operational nature of beautiful countryside construction.

Towards a capability approach to child growth: A theoretical framework.

Science.gov (United States)

Haisma, Hinke; Yousefzadeh, Sepideh; Boele Van Hensbroek, Pieter

2018-04-01

Child malnutrition is an important cause of under-5 mortality and morbidity around the globe. Despite the partial success of (inter)national efforts to reduce child mortality, under-5 mortality rates continue to be high. The multidimensional approaches of the Sustainable Development Goals may suggest new directions for rethinking strategies for reducing child mortality and malnutrition. We propose a theoretical framework for developing a "capability" approach to child growth. The current child growth monitoring practices are based on 2 assumptions: (a) that anthropometric and motor development measures are the appropriate indicators; and (b) that child growth can be assessed using a single universal standard that is applicable around the world. These practices may be further advanced by applying a capability approach to child growth, whereby growth is redefined as the achievement of certain capabilities (of society, parents, and children). This framework is similar to the multidimensional approach to societal development presented in the seminal work of Amartya Sen. To identify the dimensions of healthy child growth, we draw upon theories from the social sciences and evolutionary biology. Conceptually, we consider growth as a plural space and propose assessing growth by means of a child growth matrix in which the context is embedded in the assessment. This approach will better address the diversities and the inequalities in child growth. Such a multidimensional measure will have implications for interventions and policy, including prevention and counselling, and could have an impact on child malnutrition and mortality. © 2017 The Authors. Maternal and Child Nutrition Published by John Wiley & Sons, Ltd.

Exploring occupational and behavioral risk factors for obesity in firefighters: A theoretical framework and study design

OpenAIRE

Choi, BK; Schnall, P; Dobson, M; Israel, L; Landsbergis, P; Galassetti, P; Pontello, A; Kojaku, S; Baker, D

2011-01-01

Firefighters and police officers have the third highest prevalence of obesity among 41 male occupational groups in the United States (US). However, few studies have examined the relationship of firefighter working conditions and health behaviors with obesity. This paper presents a theoretical framework describing the relationship between working conditions, health behaviors, and obesity in firefighters. In addition, the paper describes a detailed study plan for exploring the role of occupatio...

Developing a theoretical framework to illustrate associations among patient satisfaction, body image and quality of life for women undergoing breast reconstruction.

Science.gov (United States)

Fingeret, Michelle Cororve; Nipomnick, Summer W; Crosby, Melissa A; Reece, Gregory P

2013-10-01

Within the field of breast reconstruction there is increasing focus on patient-reported outcomes related to satisfaction, body image, and quality of life. These outcomes are deemed highly relevant because the primary goal of breast reconstruction is to recreate the appearance of a breast (or breasts) that is satisfying to the patient. Prominent researchers have suggested the need to develop improved standards for outcome evaluation which can ultimately benefit patients as well as physicians. The purpose of this article is to summarize key findings in the area of patient-reported outcomes for breast reconstruction and introduce a theoretical framework for advancing research in this field. We conducted an extensive literature review of outcome studies for breast reconstruction focusing on patient-reported results. We developed a theoretical framework illustrating core patient-reported outcomes related to breast reconstruction and factors associated with these outcomes. Our theoretical model highlights domains and distinguishing features of patient satisfaction, body image, and quality of life outcomes for women undergoing breast reconstruction. This model further identifies a broad range of variables (e.g., historical/premorbid influences, disease and treatment-related factors) that have been found to influence patient-reported outcomes and need to be taken into consideration when designing future research in this area. Additional attention is given to examining the relationship between patient reported outcomes and outside evaluation of breast reconstruction. Our proposed theoretical framework suggests key opportunities to expand research in this area with the goal of optimizing body image adjustment, satisfaction, and psychosocial outcomes for the individual patient. Copyright © 2013 Elsevier Ltd. All rights reserved.

A Theoretical Framework for Serious Game Design: Exploring Pedagogy, Play and Fidelity and Their Implications for the Design Process

Science.gov (United States)

Rooney, Pauline

2012-01-01

It is widely acknowledged that digital games can provide an engaging, motivating and "fun" experience for students. However an entertaining game does not necessarily constitute a meaningful, valuable learning experience. For this reason, experts espouse the importance of underpinning serious games with a sound theoretical framework which…

An Attachment Theoretical Framework for Understanding Personality Disorders: Developmental, Neuroscience, and Psychotherapeutic Considerations

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Kenneth N. Levy

2015-04-01

Full Text Available In this paper we propose that John Bowlby's attachment theory provides a theoretically coherent, empirically based, and clinically useful model for understanding personality pathology. This theoretical framework brings parsimony and breadth to the conceptualization of the etiology, maintenance, and treatment of personality disorders (PDs. Attachment theory can explain both the intrapersonal and interpersonal difficulties common in those with PDs and is consistent with findings from studies across multiple domains of knowledge, including evolutionary biology, ethology/comparative psychology, developmental psychology, experimental social-personality psychology, and neuroscience.PDs are characterized by significant interpersonal challenges. Recently, these challenges have been hypothesized to stem from underlying maladaptive attachment schemas. Our goal is to outline and elaborate on attachment theory as a foundation for the etiology and pathology of PDs and to highlight the implications of this theory for treatment. We begin with a brief review of attachment, describing its conceptualization and assessment in both children and adults in order to examine PD development. This theoretical foundation is supported by a body of empirical research, from which we present findings from neurobiological and developmental literatures linking attachment and PDs. We then examine the role of attachment in the psychotherapy process and in treatment outcome. Further, we outline research reporting changes in attachment patterns as a result of treatment. Finally, we summarize the implications of attachment theory for understanding PDs and present possible directions for future research.

Signal restoration for NMR imaging using time-dependent gradients

International Nuclear Information System (INIS)

Frahm, J.; Haenicke, W.

1984-01-01

NMR imaging experiments that employ linear but time-dependent gradients for encoding spatial information in the time-domain signals result in distorted images when treated with conventional image reconstruction techniques. It is shown here that the phase and amplitude distortions can be entirely removed if the timeshape of the gradient is known. The method proposed is of great theoretical and experimental simplicity. It consists of a retransformation of the measured time-domain signal and corresponds to synchronisation of the signal sampling with the time-development of the gradient field strength. The procedure complements other treatments of periodically oscillating gradients in NMR imaging. (author)

The Cladistic Basis for the Phylogenetic Diversity (PD Measure Links Evolutionary Features to Environmental Gradients and Supports Broad Applications of Microbial Ecology’s “Phylogenetic Beta Diversity” Framework

Directory of Open Access Journals (Sweden)

Rob Knight

2009-11-01

Full Text Available The PD measure of phylogenetic diversity interprets branch lengths cladistically to make inferences about feature diversity. PD calculations extend conventional specieslevel ecological indices to the features level. The “phylogenetic beta diversity” framework developed by microbial ecologists calculates PD-dissimilarities between community localities. Interpretation of these PD-dissimilarities at the feature level explains the framework’s success in producing ordinations revealing environmental gradients. An example gradients space using PD-dissimilarities illustrates how evolutionary features form unimodal response patterns to gradients. This features model supports new application of existing species-level methods that are robust to unimodal responses, plus novel applications relating to climate change, commercial products discovery, and community assembly.

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

Science.gov (United States)

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

2017-01-01

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

Rethinking theoretical approaches to stigma: a Framework Integrating Normative Influences on Stigma (FINIS).

Science.gov (United States)

Pescosolido, Bernice A; Martin, Jack K; Lang, Annie; Olafsdottir, Sigrun

2008-08-01

A resurgence of research and policy efforts on stigma both facilitates and forces a reconsideration of the levels and types of factors that shape reactions to persons with conditions that engender prejudice and discrimination. Focusing on the case of mental illness but drawing from theories and studies of stigma across the social sciences, we propose a framework that brings together theoretical insights from micro, meso and macro level research: Framework Integrating Normative Influences on Stigma (FINIS) starts with Goffman's notion that understanding stigma requires a language of social relationships, but acknowledges that individuals do not come to social interaction devoid of affect and motivation. Further, all social interactions take place in a context in which organizations, media and larger cultures structure normative expectations which create the possibility of marking "difference". Labelling theory, social network theory, the limited capacity model of media influence, the social psychology of prejudice and discrimination, and theories of the welfare state all contribute to an understanding of the complex web of expectations shaping stigma. FINIS offers the potential to build a broad-based scientific foundation based on understanding the effects of stigma on the lives of persons with mental illness, the resources devoted to the organizations and families who care for them, and policies and programs designed to combat stigma. We end by discussing the clear implications this framework holds for stigma reduction, even in the face of conflicting results.

Lady Justice and the Corporate Visor: An Application of Routine Activity Theory as a Synthesized Theoretical Framework for Explaining Corporate Crime

National Research Council Canada - National Science Library

Anderson, James

2000-01-01

... social problems of violent and property crimes. However, the criminological community has all but ignored this useful theoretical tool as an apropos explanatory framework for our most insidious and prolific crime problem: corporate crime...

Harnessing Intellectual Property for Development: Some Thoughts on an Appropriate Theoretical Framework

Directory of Open Access Journals (Sweden)

Caroline Bongiwe Ncube

2013-12-01

Full Text Available This paper considers how an appropriate theoretical framework for Intellectual Property may be constructed. Such a framework would be the lens through which contested IP issues may be resolved and upon which national IP policy and legislation might be based. The paper begins by highlighting the inherent tensions in IP, which are caused by the various stakeholder interests that this body of law seeks to balance, and by the cross-cutting nature of IP. It contends that in order to more equitably balance the contesting rights of the creators and users, IP rights should be formulated and enforced so as to meet societal goals or serve public interest, be responsive to the economic environment, and take cognisance of the human rights claims of both creators and users. National socio-economic goals should inform such a framework in a way that ensures that IP is used as a means to achieve these goals and is not perceived as an end. This will require nuances in policy and legislation that meet the country's needs. In particular, as a developing country South Africa would do well to exploit available flexibilities in the various international IP agreements by which it is bound. Due regard also ought to be had to the users' need for affordable access to IP-protected goods in order that they may exercise the right to work and access to knowledge, as provided for by ss 22 and 16 of the Constitution respectively. Similarly, creators ought to be given due recognition, together with reasonable reward and remuneration for their efforts. This will be achieved through the creation of an IP system that provides protection that is compatible with the nature of the good being protected and the manner in which the creative process unfolds. Such protection should rely on registration systems are efficient, simplified and affordable. The accompanying enforcement system should be equally accessible, although the costs of enforcement would depend on the forum used to

Toward an Integrative Theoretical Framework for Explaining Beliefs about Wife Beating: A Study among Students of Nursing from Turkey

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Haj-Yahia, Muhammad M.; Uysal, Aynur

2011-01-01

An integrative theoretical framework was tested as the basis for explaining beliefs about wife beating among Turkish nursing students. Based on a survey design, 406 nursing students (404 females) in all 4 years of undergraduate studies completed a self-administered questionnaire. Questionnaires were distributed and collected from the participants…

The Meaning of Life among Secondary School Pupils. A Theoretical Framework and Some Initial Results. Research Bulletin 65.

Science.gov (United States)

Niemi, Hannele

This monograph reports on an empirical survey of 394 secondary school students investigating their desire to seek the meaning of their own lives. The theoretical framework upon which the study was based is that of Viktor E. Frankl's hypotheses that a human being wants to seek the meaning in his own life. The questionnaire consisted of tests…

The introduction of local air quality management in the United Kingdom: A review and theoretical framework

Science.gov (United States)

Longhurst, J. W. S.; Lindley, S. J.; Watson, A. F. R.; Conlan, D. E.

In the light of recent episodes of poor air quality in many of the U.K.'s major urban areas, concern has been expressed regarding the apparent inability of existing air quality control procedures to effectively tackle contemporary scenarios. As a result of this, a new philosophy for air quality control has been sought which can provide a solid basis for the preservation and future improvement of air quality. It is proposed that a suitable mechanism for this would be found through the adoption of an integrated and holistic local air quality management approach. This paper will present and discuss a theoretical framework for the application of local air quality management in the U.K. and investigate the potential of the Environment Act (1995) to provide such a framework.

"Because I Am Worth It" : A Theoretical Framework and Empirical Review of a Justification-Based Account of Self-Regulation Failure

NARCIS (Netherlands)

De Witt Huberts, Jessie C.; Evers, Catharine; De Ridder, Denise T D

Self-regulation failure is often explained as being overwhelmed by impulse. The present article proposes a novel pathway, presenting a theoretical framework and empirical review of a justification-based account of self-regulation failure. With justification we refer to making excuses for one's

Nonlocal approach to the analysis of the stress distribution in granular systems. I. Theoretical framework

Science.gov (United States)

Kenkre, V. M.; Scott, J. E.; Pease, E. A.; Hurd, A. J.

1998-05-01

A theoretical framework for the analysis of the stress distribution in granular materials is presented. It makes use of a transformation of the vertical spatial coordinate into a formal time variable and the subsequent study of a generally non-Markoffian, i.e., memory-possessing (nonlocal) propagation equation. Previous treatments are obtained as particular cases corresponding to, respectively, wavelike and diffusive limits of the general evolution. Calculations are presented for stress propagation in bounded and unbounded media. They can be used to obtain desired features such as a prescribed stress distribution within the compact.

A Framework for the Corporate Governance of Data – Theoretical Background and Empirical Evidence

Directory of Open Access Journals (Sweden)

Tomi Dahlberg

2015-06-01

Full Text Available In a modern organization, IT and digital data have transformed from being functional resources to integral elements of business strategy. Against this background, our article addresses corporate governance of digital data in general and that of aging societies in particular. To describe the role of executives and managers in data governance, we first review the corporate and IT governance literature. We then propose a theoretical framework for the governance of data: a novel construct. We apply the framework to the governance of aging societies related data, that is, to answer the question of how best to manage the provision of services to citizens with digital data enablement and support. We also disclose the results from two recent surveys, with 212 and 68 respondents respectively, on the business significance of data governance. The survey results reveal that good governance of data is considered critical to organizations. As concluding remarks, we discuss the significance of our results, our contributions to research, the limitations of our study and its managerial implications.

Bateman gradients in hermaphrodites: An extended approach to quantify sexual selection.

NARCIS (Netherlands)

Anthes, N.; David, P.; Auld, J.R.; Hoffer, J.N.A.; Jarne, P.; Koene, J.M.; Kokko, H.; Lorenzi, M.C.; Pélissié, B.; Sprenger, D.; Staikou, A.; Schärer, L.

2011-01-01

Sexual selection is often quantified using Bateman gradients, which represent sex-specific regression slopes of reproductive success on mating success and thus describe the expected fitness returns from mating more often. Although the analytical framework for Bateman gradients aimed at covering all

Justice and Equity Implications of Climate Change Adaptation: A Theoretical Evaluation Framework

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Boeckmann, Melanie; Zeeb, Hajo

2016-01-01

Climate change affects human health, and climate change adaptation aims to reduce these risks through infrastructural, behavioral, and technological measures. However, attributing direct human health effects to climate change adaptation is difficult, causing an ethical dilemma between the need for evidence of strategies and their precautionary implementation before such evidence has been generated. In the absence of conclusive evidence for individual adaptation strategies, alternative approaches to the measurement of adaptation effectiveness need to be developed. This article proposes a theoretical framework and a set of guiding questions to assess effects of adaptation strategies on seven domains of health determinants, including social, economic, infrastructure, institutional, community, environmental, and cultural determinants of health. Its focus on advancing gender equity and environmental justice concurrently with the implementation of health-related adaptation could serve as a template for policymakers and researchers. PMID:27618121

Justice and Equity Implications of Climate Change Adaptation: A Theoretical Evaluation Framework

Directory of Open Access Journals (Sweden)

Melanie Boeckmann

2016-09-01

Full Text Available Climate change affects human health, and climate change adaptation aims to reduce these risks through infrastructural, behavioral, and technological measures. However, attributing direct human health effects to climate change adaptation is difficult, causing an ethical dilemma between the need for evidence of strategies and their precautionary implementation before such evidence has been generated. In the absence of conclusive evidence for individual adaptation strategies, alternative approaches to the measurement of adaptation effectiveness need to be developed. This article proposes a theoretical framework and a set of guiding questions to assess effects of adaptation strategies on seven domains of health determinants, including social, economic, infrastructure, institutional, community, environmental, and cultural determinants of health. Its focus on advancing gender equity and environmental justice concurrently with the implementation of health-related adaptation could serve as a template for policymakers and researchers.

Thermoelectric properties of high electron concentration materials under large temperature gradients

International Nuclear Information System (INIS)

Bulat, L.P.; Stefansky, V.A.

1994-01-01

Theoretical methods of investigating of transport properties in solids under large temperature gradients are grounded. The nonlinear and non-local expressions for current density and heat flow are obtained with degenerated of current carriers gas. A number of new effects with large temperature gradients have been tested. Use of large temperature gradients leads to the increasing of the thermoelectric figure of merit. copyright 1995 American Institute of Physics

Nash Bargaining Game-Theoretic Framework for Power Control in Distributed Multiple-Radar Architecture Underlying Wireless Communication System

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Chenguang Shi

2018-04-01

Full Text Available This paper presents a novel Nash bargaining solution (NBS-based cooperative game-theoretic framework for power control in a distributed multiple-radar architecture underlying a wireless communication system. Our primary objective is to minimize the total power consumption of the distributed multiple-radar system (DMRS with the protection of wireless communication user’s transmission, while guaranteeing each radar’s target detection requirement. A unified cooperative game-theoretic framework is proposed for the optimization problem, where interference power constraints (IPCs are imposed to protect the communication user’s transmission, and a minimum signal-to-interference-plus-noise ratio (SINR requirement is employed to provide reliable target detection for each radar. The existence, uniqueness and fairness of the NBS to this cooperative game are proven. An iterative Nash bargaining power control algorithm with low computational complexity and fast convergence is developed and is shown to converge to a Pareto-optimal equilibrium for the cooperative game model. Numerical simulations and analyses are further presented to highlight the advantages and testify to the efficiency of our proposed cooperative game algorithm. It is demonstrated that the distributed algorithm is effective for power control and could protect the communication system with limited implementation overhead.

Coupling of hydraulic and electric gradients in sandy soils

Energy Technology Data Exchange (ETDEWEB)

Gregolec, G.; Zorn, R.; Kurzbach, A.; Roehl, K.E.; Czurda, K. [Dept. of Applied Geology, Univ. Karlsruhe (Germany)

2001-07-01

Laboratory studies were conducted to investigate the influence of hydraulic gradient on the migration of ions caused by an applied dc electric field. The model soil used was a uniform sand which was placed into an electrokinetic cell and saturated with sodium chloride solution. Applying only an electric gradient, steady state conditions are reached where the concentration distribution of sodium and chloride coincides with a theoretical model. The combination of electric and hydraulic gradients shows that it is possible to hinder ions from moving with the groundwater flow by applying an electric field. (orig.)

Theoretical Framework of Organizational Intelligence: A Managerial Approach to Promote Renewable Energy in Rural Economies

Directory of Open Access Journals (Sweden)

Nicolae Istudor

2016-08-01

Full Text Available The companies involved in the energy sector must reinvent themselves to be innovative and adaptable to contemporary environmental changes. The promotion of renewable energy in rural communities is a great challenge for these companies. They should focus on improving the environment scanning actions and the knowledge management (KM system and enhancing the collective intelligence to avoid the loss of information, to foster innovation, and to maintain a competitive advantage. To achieve these goals, energy companies require appropriate management tools and practices. The purpose of this study is to propose a theoretical framework of organizational intelligence (OI supported by a cross-perspective analysis of various aspects: economic intelligence (EI and KM practices, entropy processes, and organizational enablers. A pilot investigation for testing the framework in the case of Transelectrica S.A. has been elaborated. The findings reveal that the elements of the OI framework are embedded in Transelectrica’s system and they need to be further developed. As an intelligent company acting in the Romanian energy market, Transelectrica has a higher potential to promote projects in the renewable energy sector. The main conclusion highlights that OI is a multidimensional construct that provides the organization the ability to deal with environmental challenges in a “new economy”.

Exploring conceptual and theoretical frameworks for nurse practitioner education: a scoping review protocol.

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Wilson, Rosemary; Godfrey, Christina M; Sears, Kim; Medves, Jennifer; Ross-White, Amanda; Lambert, Natalie

2015-10-01

The objective of this review is to examine conceptual and/or theoretical frameworks that are relevant to nurse practitioner education.The specific review question is: What conceptual and/or theoretical frameworks are available that are relevant to the structuring of nurse practitioner education? The use of conceptual and theoretical frameworks to organize the educational curriculum of nursing programs is essential to protect and preserve the focus and clarity of nursing's distinct contribution to health care. Conceptual frameworks of nursing provide a means to look at nursing in relationship to external factors, thereby assigning meaning to the practice. Graduate level nursing education in the preparation of Nurse Practitioners (NPs) specifically and Advanced Practice Nurses (APNs) in general, is significantly compromised by the tendency to conceptualize the learning in these complex programs as being primarily related to skills-based tasks and competencies alone. According to Baumann, advanced nursing education must focus on the uniqueness of the NP position, in contrast to other health care professions. To do this, Baumann suggests using a conceptual nursing model and nursing theory as opposed to a strictly biomedical model. This allows NPs to interpret information in a way that differs from the strict biomedical model, providing opportunities for the NPs to be truly present in the lives of their patients.Canadian Nurse Practitioner (NP) practice competency documents are based primarily on the Canadian Nurses Association (CNA) Nurse Practitioner (NP) Core Competency Framework. This document defines the core set of entry-level competencies required for all NPs to practice in all Canadian jurisdictions, settings and client populations. The Core Competencies in the CNA NP Framework are organized within four main categories: professional role, responsibility and accountability; health assessment and diagnosis; therapeutic management; and health promotion and

The effect of density gradients on hydrometers

Science.gov (United States)

Heinonen, Martti; Sillanpää, Sampo

2003-05-01

Hydrometers are simple but effective instruments for measuring the density of liquids. In this work, we studied the effect of non-uniform density of liquid on a hydrometer reading. The effect induced by vertical temperature gradients was investigated theoretically and experimentally. A method for compensating for the effect mathematically was developed and tested with experimental data obtained with the MIKES hydrometer calibration system. In the tests, the method was found reliable. However, the reliability depends on the available information on the hydrometer dimensions and density gradients.

Non-Conventional Thermodynamics and Models of Gradient Elasticity

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Hans-Dieter Alber

2018-03-01

Full Text Available We consider material bodies exhibiting a response function for free energy, which depends on both the strain and its gradient. Toupin–Mindlin’s gradient elasticity is characterized by Cauchy stress tensors, which are given by space-like Euler–Lagrange derivative of the free energy with respect to the strain. The present paper aims at developing a first version of gradient elasticity of non-Toupin–Mindlin’s type, i.e., a theory employing Cauchy stress tensors, which are not necessarily expressed as Euler–Lagrange derivatives. This is accomplished in the framework of non-conventional thermodynamics. A one-dimensional boundary value problem is solved in detail in order to illustrate the differences of the present theory with Toupin–Mindlin’s gradient elasticity theory.

Global correlation imaging of magnetic total field gradients

International Nuclear Information System (INIS)

Guo, Lianghui; Meng, Xiaohong; Shi, Lei

2012-01-01

Firstly we introduce the correlation imaging approach for the x-, y- and z-gradients of a magnetic total field anomaly for deriving the distribution of equivalent magnetic sources of the subsurface. In this approach, the subsurface space is divided into a regular grid, and then a correlation coefficient function is computed at each grid node, based on the cross-correlation between the x-gradient (or y-gradient or z-gradient) of the observed magnetic total field anomaly and the x-gradient (or y-gradient or z-gradient) of the theoretical magnetic total field anomaly due to a magnetic dipole. The resultant correlation coefficient is used to describe the probability of a magnetic dipole occurring at the node. We then define a global correlation coefficient function for comprehensively delineating the probability of an occurrence of a magnetic dipole, which takes, at each node, the maximum positive value of the corresponding correlation coefficient function of the three gradients. We finally test the approach both on synthetic data and real data from a metallic deposit area in the middle-lower reaches of the Yangtze River, China. (paper)

Global Leadership Study: A Theoretical Framework

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Perkins, Anne W.

2009-01-01

Traditional leadership theory and research courses do not adequately prepare students for cross-cultural leadership. This article notes six premises of Western theories and demonstrates the limitations of these premises in non-Western settings. A framework for the study of cross-cultural leadership, The Global Leadership-Learning Pyramid, is…

HG2006 Workshop on High-Gradient Radio Frequency

CERN Multimedia

2006-01-01

Meeting to be held at CERN on 25-27 September 2006 in Room 40/S2-B01 (Building 40). The objective of the workshop is to bring the high-gradient RF community together to present and discuss recent theoretical and experimental developments. Significant progress has recently been made in understanding the basic physics of rf breakdown and developing techniques for achieving higher gradients. This workshop should contribute to maintaining these efforts and to promoting contacts and collaboration. The scientific programme will be organized in half day sessions dedicated to: High-gradient rf experimental results Theory and computation High-gradient technology, materials and processing Specialized experiments on related high-gradient or high-power phenomenon like dc discharge and pulsed surface heating Reports from collaborations and projects. Each session will consist of selected presentations followed by a dedicated discussion. Information about the meeting and participant registration is available at http...

Exploring end user adoption and maintenance of a telephone-based physical activity counseling service for individuals with physical disabilities using the Theoretical Domains Framework.

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Tomasone, Jennifer R; Arbour-Nicitopoulos, Kelly P; Pila, Eva; Lamontagne, Marie-Eve; Cummings, Isabelle; Latimer-Cheung, Amy E; Routhier, François

2017-06-01

In Canada, two counseling services are offered to facilitate physical activity participation among persons with physical disabilities, yet both have encountered concerns related to the recruitment and retainment of clients. The purpose of this paper is to explore factors related to service adoption among nonusers, and the barriers and facilitators to maintaining service participation among adopters. Individuals who had never enrolled in the services (nonusers, n = 13) as well as current/previous service clients (adopters, n = 26) participated in interviews based on the Theoretical Domains Framework. Transcripts were subjected to deductive thematic analysis according to participant group. Fifteen themes relating to service adoption within 10 of the 12 theoretical domains were identified for nonusers, while 23 themes relating to maintenence of service participation were identified across all 12 theoretical domains for adopters. The findings provide strategies to improve recruitment, adoption, and retention of clients in counseling services and to enhance the experiences of targeted service users. Implications for Rehabiliation Peer support and education for equipment use should be built into physical activity programs to encourage participation among persons with physical disabilities. Programs that encourage physical activity among individuals with disabilities should be designed by practitioners to be responsive to a variety of needs, which are addressed in the program's advertisements and offerings. The Theoretical Domains Framework is a useful framework for providing valuable insight about clients' experiences of adoption and maintenance of a behavior change service, suggesting merit in other rehabilitation settings.

A single theoretical framework for circular features processing in humans: orientation and direction of motion compared

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Tzvetomir eTzvetanov

2012-05-01

Full Text Available Common computational principles underly processing of various visual features in the cortex. They are considered to create similar patterns of contextual modulations in behavioral studies for different features as orientation and direction of motion. Here, I studied the possibility that a single theoretical framework, implemented in different visual areas, of circular feature coding and processing could explain these similarities in observations. Stimuli were created that allowed direct comparison of the contextual effects on orientation and motion direction with two different psychophysical probes: changes in weak and strong signal perception. One unique simplified theoretical model of circular feature coding including only inhibitory interactions, and decoding through standard vector average, successfully predicted the similarities in the two domains, while different feature population characteristics explained well the differences in modulation on both experimental probes. These results demonstrate how a single computational principle underlies processing of various features across the cortices.

Surface Termination of the Metal-Organic Framework HKUST-1: A Theoretical Investigation.

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Amirjalayer, Saeed; Tafipolsky, Maxim; Schmid, Rochus

2014-09-18

The surface morphology and termination of metal-organic frameworks (MOF) is of critical importance in many applications, but the surface properties of these soft materials are conceptually different from those of other materials like metal or oxide surfaces. Up to now, experimental investigations are scarce and theoretical simulations have focused on the bulk properties. The possible surface structure of the archetypal MOF HKUST-1 is investigated by a first-principles derived force field in combination with DFT calculations of model systems. The computed surface energies correctly predict the [111] surface to be most stable and allow us to obtain an unprecedented atomistic picture of the surface termination. Entropic factors are identified to determine the preferred surface termination and to be the driving force for the MOF growth. On the basis of this, reported strategies like employing "modulators" during the synthesis to tailor the crystal morphology are discussed.

Bayesian Decision Theoretical Framework for Clustering

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Chen, Mo

2011-01-01

In this thesis, we establish a novel probabilistic framework for the data clustering problem from the perspective of Bayesian decision theory. The Bayesian decision theory view justifies the important questions: what is a cluster and what a clustering algorithm should optimize. We prove that the spectral clustering (to be specific, the…

Algebraic Specifications, Higher-order Types and Set-theoretic Models

DEFF Research Database (Denmark)

Kirchner, Hélène; Mosses, Peter David

2001-01-01

, and power-sets. This paper presents a simple framework for algebraic specifications with higher-order types and set-theoretic models. It may be regarded as the basis for a Horn-clause approximation to the Z framework, and has the advantage of being amenable to prototyping and automated reasoning. Standard......In most algebraic  specification frameworks, the type system is restricted to sorts, subsorts, and first-order function types. This is in marked contrast to the so-called model-oriented frameworks, which provide higer-order types, interpreted set-theoretically as Cartesian products, function spaces...... set-theoretic models are considered, and conditions are given for the existence of initial reduct's of such models. Algebraic specifications for various set-theoretic concepts are considered....

A Theoretical Framework on Using Social Stories with the Creative Arts for Individuals on the Autistic Spectrum

OpenAIRE

R. Bawazir; P. Jones

2017-01-01

Social Stories are widely used to teach social and communication skills or concepts to individuals on the autistic spectrum. This paper presents a theoretical framework for using Social Stories in conjunction with the creative arts. The paper argues that Bandura's social learning theory can be used to explain the mechanisms behind Social Stories and the way they influence changes in response, while Gardner's multiple intelligences theory can be used simultaneously to demonstrate the role of t...

Theoretical maximal storage of hydrogen in zeolitic frameworks.

Science.gov (United States)

Vitillo, Jenny G; Ricchiardi, Gabriele; Spoto, Giuseppe; Zecchina, Adriano

2005-12-07

Physisorption and encapsulation of molecular hydrogen in tailored microporous materials are two of the options for hydrogen storage. Among these materials, zeolites have been widely investigated. In these materials, the attained storage capacities vary widely with structure and composition, leading to the expectation that materials with improved binding sites, together with lighter frameworks, may represent efficient storage materials. In this work, we address the problem of the determination of the maximum amount of molecular hydrogen which could, in principle, be stored in a given zeolitic framework, as limited by the size, structure and flexibility of its pore system. To this end, the progressive filling with H2 of 12 purely siliceous models of common zeolite frameworks has been simulated by means of classical molecular mechanics. By monitoring the variation of cell parameters upon progressive filling of the pores, conclusions are drawn regarding the maximum storage capacity of each framework and, more generally, on framework flexibility. The flexible non-pentasils RHO, FAU, KFI, LTA and CHA display the highest maximal capacities, ranging between 2.86-2.65 mass%, well below the targets set for automotive applications but still in an interesting range. The predicted maximal storage capacities correlate well with experimental results obtained at low temperature. The technique is easily extendable to any other microporous structure, and it can provide a method for the screening of hypothetical new materials for hydrogen storage applications.

Assessing the impact of renewable energy deployment on local sustainability: Towards a theoretical framework

Energy Technology Data Exchange (ETDEWEB)

del Rio, Pablo [Facultad de Ciencias Juridicas y Sociales de Toledo, Universidad de Castilla-La Mancha, C/Cobertizo de S. Pedro Martir s/n, Toledo-45071 (Spain); Burguillo, Mercedes [Facultad de Ciencias Economicas y Empresariales, Universidad de Alcala, Pza. de la Victoria 3, 28802 Alcala de Henares, Madrid (Spain)

2008-06-15

Renewable energy sources (RES) have a large potential to contribute to the sustainable development (SD) of specific territories by providing them with a wide variety of socioeconomic and environmental benefits. However, the existing literature has put much emphasis on the environmental benefits (including the reduction of global and local pollutants), while socioeconomic impacts have not received a comparable attention. These include diversification of energy supply, enhanced regional and rural development opportunities, creation of a domestic industry and employment opportunities. With the exception of the diversification and security of energy supply, these benefits have usually been mentioned, but their analysis has been too general (i.e., mostly at the national level) and a focus on the regional and, even more so, the local level, has been lacking. At most, studies provide scattered evidence of some of those regional and local benefits, but without an integrated conceptual framework to analyse them. This paper tries to make a contribution in this regard by developing an integrated theoretical framework which allows a comprehensive analysis of the impact of renewable energy on local sustainability and which can be empirically applied to identify these benefits in different territories. (author)

Public administration and R&D localisation by pharmaceutical and biotech companies: a theoretical framework and the Italian case-study.

Science.gov (United States)

Jommi, Claudio; Paruzzolo, Silvia

2007-04-01

This article has two objectives. It firstly provides a general framework for variables that influence R&D (Research and Development) localisation by pharmaceutical and biotech companies. The analysis of R&D localization includes both in-house R&D and contracted R&D. Following a systematic literature search, these variables were classified into four distinct categories: regulatory environment, institutional framework, national systems of innovation and local development and specialisation. The authors highlight that some of these factors directly depend on the action of public administrations (e.g., patent protection, price regulation, public investments in research, and incentives to private companies); others are indirectly influenced by public policies (e.g., GDP growth rate, infrastructures). This theoretical framework was used to analyse the Italian case-study. Pros and cons of the Italian context were investigated from the point of view of multinational pharmaceutical companies and the Italian Association of Biotech Companies. Interviews were chosen as the most appropriate data gathering technique given the exploratory nature of the study of the Italian context. The paper is divided into five parts. A brief introduction provides figures showing that Europe has been loosing positions compared with other Continents and the same has occurred in Italy compared with other EU countries. The second one illustrates the methodology. The third one is focused on variables affecting R&D localisation. In the fourth section the Italian case-study is discussed. Theoretical and empirical findings are summarised and discussed in the conclusions.

Energetic dislocation interactions and thermodynamical aspects of strain gradient crystal plasticity theories

NARCIS (Netherlands)

Ertürk, I.; Dommelen, van J.A.W.; Geers, M.G.D.

2009-01-01

This paper focuses on the unification of two frequently used and apparently different strain gradient crystal plasticity frameworks: (i) the physicallymotivated strain gradient crystal plasticity models proposed by Evers et al. (2004a,b) and Bayley et al. (2006, 2007) (here referred to as

Primordial vorticity and gradient expansion

CERN Document Server

Giovannini, Massimo

2012-01-01

The evolution equations of the vorticities of the electrons, ions and photons in a pre-decoupling plasma are derived, in a fully inhomogeneous geometry, by combining the general relativistic gradient expansion and the drift approximation within the Adler-Misner-Deser decomposition. The vorticity transfer between the different species is discussed in this novel framework and a set of general conservation laws, connecting the vorticities of the three-component plasma with the magnetic field intensity, is derived. After demonstrating that a source of large-scale vorticity resides in the spatial gradients of the geometry and of the electromagnetic sources, the total vorticity is estimated to lowest order in the spatial gradients and by enforcing the validity of the momentum constraint. By acknowledging the current bounds on the tensor to scalar ratio in the (minimal) tensor extension of the $\\Lambda$CDM paradigm the maximal comoving magnetic field induced by the total vorticity turns out to be, at most, of the or...

Revisiting Symbolic Interactionism as a Theoretical Framework Beyond the Grounded Theory Tradition.

Science.gov (United States)

Handberg, Charlotte; Thorne, Sally; Midtgaard, Julie; Nielsen, Claus Vinther; Lomborg, Kirsten

2015-08-01

The tight bond between grounded theory (GT) and symbolic interactionism (SI) is well known within the qualitative health research field. We aimed to disentangle this connection through critical reflection on the conditions under which it might add value as an underpinning to studies outside the GT tradition. Drawing on an examination of the central tenets of SI, we illustrate with a field study using interpretive description as methodology how SI can be applied as a theoretical lens through which layers of socially constructed meaning can help surface the subjective world of patients. We demonstrate how SI can function as a powerful framework for human health behavior research through its capacity to orient questions, inform design options, and refine analytic directions. We conclude that using SI as a lens can serve as a translation mechanism in our quest to interpret the subjective world underlying patients' health and illness behavior. © The Author(s) 2014.

Theoretical framework of integrated strategic performance management system

OpenAIRE

Mitrović, Zorica; Todorović, Marija; Bjelica, Dragan

2015-01-01

The aim of this paper is to present a conceptual model of the integrated strategic performance management system. This model is conceptual framework designed as a result of research that shows significant benefits of integrated application of strategic management and performance management in organizations. The framework consists of five steps: establishing a planning system, establishing of performance measurement system, establishing an accountability system, establishing of the knowledge m...

GenGIS 2: geospatial analysis of traditional and genetic biodiversity, with new gradient algorithms and an extensible plugin framework.

Directory of Open Access Journals (Sweden)

Donovan H Parks

Full Text Available GenGIS is free and open source software designed to integrate biodiversity data with a digital map and information about geography and habitat. While originally developed with microbial community analyses and phylogeography in mind, GenGIS has been applied to a wide range of datasets. A key feature of GenGIS is the ability to test geographic axes that can correspond to routes of migration or gradients that influence community similarity. Here we introduce GenGIS version 2, which extends the linear gradient tests introduced in the first version to allow comprehensive testing of all possible linear geographic axes. GenGIS v2 also includes a new plugin framework that supports the development and use of graphically driven analysis packages: initial plugins include implementations of linear regression and the Mantel test, calculations of alpha-diversity (e.g., Shannon Index for all samples, and geographic visualizations of dissimilarity matrices. We have also implemented a recently published method for biomonitoring reference condition analysis (RCA, which compares observed species richness and diversity to predicted values to determine whether a given site has been impacted. The newest version of GenGIS supports vector data in addition to raster files. We demonstrate the new features of GenGIS by performing a full gradient analysis of an Australian kangaroo apple data set, by using plugins and embedded statistical commands to analyze human microbiome sample data, and by applying RCA to a set of samples from Atlantic Canada. GenGIS release versions, tutorials and documentation are freely available at http://kiwi.cs.dal.ca/GenGIS, and source code is available at https://github.com/beiko-lab/gengis.

Using Bourdieu's Theoretical Framework to Examine How the Pharmacy Educator Views Pharmacy Knowledge.

Science.gov (United States)

Waterfield, Jon

2015-12-25

To explore how different pharmacy educators view pharmacy knowledge within the United Kingdom MPharm program and to relate these findings to Pierre Bourdieu's theoretical framework. Twelve qualitative interviews were conducted with 4 faculty members from 3 different types of schools of pharmacy in the United Kingdom: a newer school, an established teaching-based school, and an established research-intensive school. Selection was based on a representation of both science-based and practice-based disciplines, gender balance, and teaching experience. The interview transcripts indicated how these members of the academic community describe knowledge. There was a polarization between science-based and practice-based educators in terms of Bourdieu's description of field, species of capital, and habitus. A Bourdieusian perspective on the differences among faculty member responses supports our understanding of curriculum integration and offers some practical implications for the future development of pharmacy programs.

Quality Affordable Housing: A Theoretical Framework for Planning and Design of Quality Housing

Directory of Open Access Journals (Sweden)

Noor Sharipah Sultan Sidi

2011-10-01

Full Text Available The provision of adequate, good or quality housing for the population has always been a major challenge and task for most nations in the world particularly the developing countries. As such various measures have been undertaken towards this end. However, the major constraint or problem in this respect has always been in defining the criteria for quality housing and establishing the standards of quality housing particularly with respect to the parameters in the determination of quality as some of the parameters are subjective and contextual such as psychological, cultural and environmental aspects. This paper is aimed at discussing the concept of quality housing and establishing the parameters and theoretical framework which can be used by researchers, town planners, architects, policy makers and others in the formulation of criteria / guidelines for the planning and design of quality housing.

Transformation of Adolescent Peer Relations in the Social Media Context: Part 1-A Theoretical Framework and Application to Dyadic Peer Relationships.

Science.gov (United States)

Nesi, Jacqueline; Choukas-Bradley, Sophia; Prinstein, Mitchell J

2018-04-07

Investigators have long recognized that adolescents' peer experiences provide a crucial context for the acquisition of developmental competencies, as well as potential risks for a range of adjustment difficulties. However, recent years have seen an exponential increase in adolescents' adoption of social media tools, fundamentally reshaping the landscape of adolescent peer interactions. Although research has begun to examine social media use among adolescents, researchers have lacked a unifying framework for understanding the impact of social media on adolescents' peer experiences. This paper represents Part 1 of a two-part theoretical review, in which we offer a transformation framework to integrate interdisciplinary social media scholarship and guide future work on social media use and peer relations from a theory-driven perspective. We draw on prior conceptualizations of social media as a distinct interpersonal context and apply this understanding to adolescents' peer experiences, outlining features of social media with particular relevance to adolescent peer relations. We argue that social media transforms adolescent peer relationships in five key ways: by changing the frequency or immediacy of experiences, amplifying experiences and demands, altering the qualitative nature of interactions, facilitating new opportunities for compensatory behaviors, and creating entirely novel behaviors. We offer an illustration of the transformation framework applied to adolescents' dyadic friendship processes (i.e., experiences typically occurring between two individuals), reviewing existing evidence and offering theoretical implications. Overall, the transformation framework represents a departure from the prevailing approaches of prior peer relations work and a new model for understanding peer relations in the social media context.

Dealing with grief related to loss by death and chronic pain: An integrated theoretical framework. Part 1

Directory of Open Access Journals (Sweden)

Bodil Furnes

2010-05-01

Full Text Available Bodil Furnes, Elin DysvikUniversity of Stavanger, Faculty of Social Sciences, Department of Health Studies, Stavanger, NorwayObjective: Based on the present authors’ research and several approaches to grief related to loss by death and nonmalignant chronic pain, the paper suggests a new integrated theoretical framework for intervention in clinical settings.Methods: An open qualitative review of the literature on grief theories was performed searching for a new integrated approach in the phenomenological tradition. We then investigated the relationship between grief, loss and chronic nonmalignant pain, looking for main themes and connections and how these could be best understood in a more holistic manner.Results: Two main themes were formulated, “relearning the world” and “adaptation”. Between these themes a continuous movement emerged involving experience such as: “despair and hope”, “lack of understanding and insight”, “meaning disruption and increased meaning”, and “bodily discomfort and reintegrated body”. These were identified as paired subthemes.Conclusions: Grief as a distinctive experience means that health care must be aimed at each individual experience and situation. Grief experience and working with grief are considered in terms of relearning the world while walking backwards and living forwards, as described in our integrated model. We consider that this theoretical framework regarding grief should offer an integrated foundation for health care workers who are working with people experiencing grief caused by death or chronic pain.Keywords: health care, loss, grief

HIRFL-SSC trim coil currents calculation by conjugate gradients method

International Nuclear Information System (INIS)

Liu, W.

2005-01-01

For accelerating different kinds of ions to various energies, the HIRFL-SSC should form the corresponding isochronous magnetic field by its main coil and trim coils. Previously, there were errors in fitting the theoretical isochronous magnetic field in the small radius region, which led to some operation difficulties for ion acceleration in the inject region. After further investigation of the restrictive condition of the maximum current limitation, the trim coil currents for fitting the theoretical isochronous magnetic field were recalculated by the conjugate gradients method. Better results were obtained in the operation of HIRFL-SSC. This article introduces the procedure to calculate the trim coil currents. The calculation method of conjugate gradients is introduced and the fitting error is analysed. (author)

A modified theoretical framework to assess implementation fidelity of adaptive public health interventions.

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Pérez, Dennis; Van der Stuyft, Patrick; Zabala, Maríadel Carmen; Castro, Marta; Lefèvre, Pierre

2016-07-08

One of the major debates in implementation research turns around fidelity and adaptation. Fidelity is the degree to which an intervention is implemented as intended by its developers. It is meant to ensure that the intervention maintains its intended effects. Adaptation is the process of implementers or users bringing changes to the original design of an intervention. Depending on the nature of the modifications brought, adaptation could either be potentially positive or could carry the risk of threatening the theoretical basis of the intervention, resulting in a negative effect on expected outcomes. Adaptive interventions are those for which adaptation is allowed or even encouraged. Classical fidelity dimensions and conceptual frameworks do not address the issue of how to adapt an intervention while still maintaining its effectiveness. We support the idea that fidelity and adaptation co-exist and that adaptations can impact either positively or negatively on the intervention's effectiveness. For adaptive interventions, research should answer the question how an adequate fidelity-adaptation balance can be reached. One way to address this issue is by looking systematically at the aspects of an intervention that are being adapted. We conducted fidelity research on the implementation of an empowerment strategy for dengue prevention in Cuba. In view of the adaptive nature of the strategy, we anticipated that the classical fidelity dimensions would be of limited use for assessing adaptations. The typology we used in the assessment-implemented, not-implemented, modified, or added components of the strategy-also had limitations. It did not allow us to answer the question which of the modifications introduced in the strategy contributed to or distracted from outcomes. We confronted our empirical research with existing literature on fidelity, and as a result, considered that the framework for implementation fidelity proposed by Carroll et al. in 2007 could potentially meet

Theoretical Models, Assessment Frameworks and Test Construction.

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Chalhoub-Deville, Micheline

1997-01-01

Reviews the usefulness of proficiency models influencing second language testing. Findings indicate that several factors contribute to the lack of congruence between models and test construction and make a case for distinguishing between theoretical models. Underscores the significance of an empirical, contextualized and structured approach to the…

Hierarchical representations of the five-factor model of personality in predicting job performance: integrating three organizing frameworks with two theoretical perspectives.

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Judge, Timothy A; Rodell, Jessica B; Klinger, Ryan L; Simon, Lauren S; Crawford, Eean R

2013-11-01

Integrating 2 theoretical perspectives on predictor-criterion relationships, the present study developed and tested a hierarchical framework in which each five-factor model (FFM) personality trait comprises 2 DeYoung, Quilty, and Peterson (2007) facets, which in turn comprise 6 Costa and McCrae (1992) NEO facets. Both theoretical perspectives-the bandwidth-fidelity dilemma and construct correspondence-suggest that lower order traits would better predict facets of job performance (task performance and contextual performance). They differ, however, as to the relative merits of broad and narrow traits in predicting a broad criterion (overall job performance). We first meta-analyzed the relationship of the 30 NEO facets to overall job performance and its facets. Overall, 1,176 correlations from 410 independent samples (combined N = 406,029) were coded and meta-analyzed. We then formed the 10 DeYoung et al. facets from the NEO facets, and 5 broad traits from those facets. Overall, results provided support for the 6-2-1 framework in general and the importance of the NEO facets in particular. (c) 2013 APA, all rights reserved.

A theoretical framework for determining cerebral vascular function and heterogeneity from dynamic susceptibility contrast MRI.

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Digernes, Ingrid; Bjørnerud, Atle; Vatnehol, Svein Are S; Løvland, Grete; Courivaud, Frédéric; Vik-Mo, Einar; Meling, Torstein R; Emblem, Kyrre E

2017-06-01

Mapping the complex heterogeneity of vascular tissue in the brain is important for understanding cerebrovascular disease. In this translational study, we build on previous work using vessel architectural imaging (VAI) and present a theoretical framework for determining cerebral vascular function and heterogeneity from dynamic susceptibility contrast magnetic resonance imaging (MRI). Our tissue model covers realistic structural architectures for vessel branching and orientations, as well as a range of hemodynamic scenarios for blood flow, capillary transit times and oxygenation. In a typical image voxel, our findings show that the apparent MRI relaxation rates are independent of the mean vessel orientation and that the vortex area, a VAI-based parameter, is determined by the relative oxygen saturation level and the vessel branching of the tissue. Finally, in both simulated and patient data, we show that the relative distributions of the vortex area parameter as a function of capillary transit times show unique characteristics in normal-appearing white and gray matter tissue, whereas tumour-voxels in comparison display a heterogeneous distribution. Collectively, our study presents a comprehensive framework that may serve as a roadmap for in vivo and per-voxel determination of vascular status and heterogeneity in cerebral tissue.

A conceptual framework related to ICT-AT competence development: The theoretical foundations of ENTELIS.

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Mavrou, Katerina; Hoogerwerf, Evert-Jan; Meletiou-Mavrotheris, Maria; Kärki, Anne; Sallinen, Merja

2015-01-01

This paper provides an overview of the construction of a conceptual framework regarding ICT-Assistive Technology (ICT-AT) competence development, designed to gain awareness of the elements involved and to facilitate the understanding and exchange among stakeholders of the ENTELIS (European Network for Technology Enhanced Learning in an Inclusive Society) project. The framework was designed based on the basic principles of Activity Theory, which however have been adapted and adjusted to the project's objectives. Hence, it includes a map of actors and other parameters functioning in a person surrounding "ecosystem", and it allows us to understand and map roles, expectations, barriers, as well as to devise solutions to tackle digital divide. Taking as a starting and central point the person and his/her wish to self-determination and fulfilment (quality of life) and the related needs, it provides a map of how the various concepts and variables interact within the theoretical and methodological perspective of the collection, description and assessment of experiences in ICT-AT education and competences development of persons with disabilities (PwD) of all ages. The conceptual framework represents two interacting learning activity systems: (a) the internal system of the end-user, which includes the end-user and his/her needs, the setting where learning takes place and the other actors involved, and (b) the external system, which embraces the internal system but also wider issues of policy and practice and experiences and 'actors' that contribute to the development and use of ICT and ICT-AT skills in all areas of life. The elements of these systems and their interaction provide the basis for analysing experiences and advancing knowledge relevant for bridging the digital divide.

Strain gradient crystal plasticity effects on flow localization

DEFF Research Database (Denmark)

Borg, Ulrik

2007-01-01

for metals described by the reformulated Fleck-Hutchinson strain gradient plasticity theory. The theory is implemented numerically within a finite element framework using slip rate increments and displacement increments as state variables. The formulation reduces to the classical crystal plasticity theory...... in the absence of strain gradients. The model is used to study the effect of an internal material length scale on the localization of plastic flow in shear bands in a single crystal under plane strain tension. It is shown that the mesh sensitivity is removed when using the nonlocal material model considered...

Theoretical Framework of Researcher Knowledge Development in Mathematics Education

Science.gov (United States)

Kontorovich, Igor'

2016-01-01

The goal of this paper is to present a framework of researcher knowledge development in conducting a study in mathematics education. The key components of the framework are: knowledge germane to conducting a particular study, processes of knowledge accumulation, and catalyzing filters that influence a researcher's decision making. The components…

Entanglement-Gradient Routing for Quantum Networks.

Science.gov (United States)

Gyongyosi, Laszlo; Imre, Sandor

2017-10-27

We define the entanglement-gradient routing scheme for quantum repeater networks. The routing framework fuses the fundamentals of swarm intelligence and quantum Shannon theory. Swarm intelligence provides nature-inspired solutions for problem solving. Motivated by models of social insect behavior, the routing is performed using parallel threads to determine the shortest path via the entanglement gradient coefficient, which describes the feasibility of the entangled links and paths of the network. The routing metrics are derived from the characteristics of entanglement transmission and relevant measures of entanglement distribution in quantum networks. The method allows a moderate complexity decentralized routing in quantum repeater networks. The results can be applied in experimental quantum networking, future quantum Internet, and long-distance quantum communications.

On modeling micro-structural evolution using a higher order strain gradient continuum theory

DEFF Research Database (Denmark)

El-Naaman, S. A.; Nielsen, K. L.; Niordson, C. F.

2016-01-01

is to improve the micro-structural response predicted using strain gradient crystal plasticity within a continuum mechanics framework. One approach to modeling the dislocation structures observed is through a back stress formulation, which can be related directly to the strain gradient energy. The present work...... the experimentally observed micro-structural behavior, within a framework based on continuous field quantities, poses obvious challenges, since the evolution of dislocation structures is inherently a discrete and discontinuous process. This challenge, in particular, motivates the present study, and the aim...... offers an investigation of constitutive equations for the back stress based on both considerations of the gradient energy, but also includes results obtained from a purely phenomenological starting point. The influence of model parameters is brought out in a parametric study, and it is demonstrated how...

How do small groups make decisions? : A theoretical framework to inform the implementation and study of clinical competency committees.

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Chahine, Saad; Cristancho, Sayra; Padgett, Jessica; Lingard, Lorelei

2017-06-01

In the competency-based medical education (CBME) approach, clinical competency committees are responsible for making decisions about trainees' competence. However, we currently lack a theoretical model for group decision-making to inform this emerging assessment phenomenon. This paper proposes an organizing framework to study and guide the decision-making processes of clinical competency committees.This is an explanatory, non-exhaustive review, tailored to identify relevant theoretical and evidence-based papers related to small group decision-making. The search was conducted using Google Scholar, Web of Science, MEDLINE, ERIC, and PsycINFO for relevant literature. Using a thematic analysis, two researchers (SC & JP) met four times between April-June 2016 to consolidate the literature included in this review.Three theoretical orientations towards group decision-making emerged from the review: schema, constructivist, and social influence. Schema orientations focus on how groups use algorithms for decision-making. Constructivist orientations focus on how groups construct their shared understanding. Social influence orientations focus on how individual members influence the group's perspective on a decision. Moderators of decision-making relevant to all orientations include: guidelines, stressors, authority, and leadership.Clinical competency committees are the mechanisms by which groups of clinicians will be in charge of interpreting multiple assessment data points and coming to a shared decision about trainee competence. The way in which these committees make decisions can have huge implications for trainee progression and, ultimately, patient care. Therefore, there is a pressing need to build the science of how such group decision-making works in practice. This synthesis suggests a preliminary organizing framework that can be used in the implementation and study of clinical competency committees.

Pulmonary rehabilitation referral and participation are commonly influenced by environment, knowledge, and beliefs about consequences: a systematic review using the Theoretical Domains Framework

Directory of Open Access Journals (Sweden)

Narelle S Cox

2017-04-01

Trial registration: PROSPERO CRD42015015976. [Cox NS, Oliveira CC, Lahham A, Holland AE (2017 Pulmonary rehabilitation referral and participation are commonly influenced by environment, knowledge, and beliefs about consequences: a systematic review using the Theoretical Domains Framework. Journal of Physiotherapy 63: 84–93

Assessing Two Theoretical Frameworks of Civic Engagement

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García-Cabrero, Benilde; Pérez-Martínez, María Guadalupe; Sandoval-Hernández, Andrés; Caso-Niebla, Joaquín; Díaz-López, Carlos David

2016-01-01

The purpose of this study was to empirically test two major theoretical models: a modified version of the social capital model (Pattie, Seyd and Whiteley, 2003), and the Informed Social Engagement Model (Barr and Selman, 2014; Selman and Kwok, 2010), to explain civic participation and civic knowledge of adolescents from Chile, Colombia and Mexico,…

A game-theoretic framework for estimating a health purchaser's willingness-to-pay for health and for expansion.

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Yaesoubi, Reza; Roberts, Stephen D

2010-12-01

A health purchaser's willingness-to-pay (WTP) for health is defined as the amount of money the health purchaser (e.g. a health maximizing public agency or a profit maximizing health insurer) is willing to spend for an additional unit of health. In this paper, we propose a game-theoretic framework for estimating a health purchaser's WTP for health in markets where the health purchaser offers a menu of medical interventions, and each individual in the population selects the intervention that maximizes her prospect. We discuss how the WTP for health can be employed to determine medical guidelines, and to price new medical technologies, such that the health purchaser is willing to implement them. The framework further introduces a measure for WTP for expansion, defined as the amount of money the health purchaser is willing to pay per person in the population served by the health provider to increase the consumption level of the intervention by one percent without changing the intervention price. This measure can be employed to find how much to invest in expanding a medical program through opening new facilities, advertising, etc. Applying the proposed framework to colorectal cancer screening tests, we estimate the WTP for health and the WTP for expansion of colorectal cancer screening tests for the 2005 US population.

Foreign direct investment and economic growth: A theoretical framework

Directory of Open Access Journals (Sweden)

Edmore Mahembe

2014-05-01

Full Text Available The relationship between FDI and economic growth has attracted considerable attention over the years. Despite the important role played by FDI in economic growth, a number of policy-makers have not fully understood the theoretical linkage between FDI and economic growth. The aim of this paper, therefore, is to review the theoretical literature on the relationship between FDI and economic growth in a stylized fashion. The theoretical literature reviewed in this study show that FDI is a key contributor to the economic growth of the host country. FDI affects economic growth through two broad channels: (i FDI can encourage the adoption of new technologies in the production process through technological spillovers; and (ii FDI may stimulate knowledge transfers, both in terms of labour training and skill acquisition, and also by introducing alternative management practices and better organisational arrangements.

Quantifying behavioural determinants relating to health professional reporting of medication errors: a cross-sectional survey using the Theoretical Domains Framework.

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Alqubaisi, Mai; Tonna, Antonella; Strath, Alison; Stewart, Derek

2016-11-01

The aims of this study were to quantify the behavioural determinants of health professional reporting of medication errors in the United Arab Emirates (UAE) and to explore any differences between respondents. A cross-sectional survey of patient-facing doctors, nurses and pharmacists within three major hospitals of Abu Dhabi, the UAE. An online questionnaire was developed based on the Theoretical Domains Framework (TDF, a framework of behaviour change theories). Principal component analysis (PCA) was used to identify components and internal reliability determined. Ethical approval was obtained from a UK university and all hospital ethics committees. Two hundred and ninety-four responses were received. Questionnaire items clustered into six components of knowledge and skills, feedback and support, action and impact, motivation, effort and emotions. Respondents generally gave positive responses for knowledge and skills, feedback and support and action and impact components. Responses were more neutral for the motivation and effort components. In terms of emotions, the component with the most negative scores, there were significant differences in terms of years registered as health professional (those registered longest most positive, p = 0.002) and age (older most positive, p Theoretical Domains Framework to quantify the behavioural determinants of health professional reporting of medication errors. • Questionnaire items relating to emotions surrounding reporting generated the most negative responses with significant differences in terms of years registered as health professional (those registered longest most positive) and age (older most positive) with no differences for gender and health profession. • Interventions based on behaviour change techniques mapped to emotions should be prioritised for development.

Dynamics of gradient formation by intracellular shuttling

Energy Technology Data Exchange (ETDEWEB)

Berezhkovskii, Alexander M. [Mathematical and Statistical Computing Laboratory, Division of Computational Bioscience, Center for Information Technology, National Institutes of Health, Bethesda, Maryland 20892 (United States); Shvartsman, Stanislav Y. [Department of Chemical and Biological Engineering and Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey 08544 (United States)

2015-08-21

A number of important cellular functions rely on the formation of intracellular protein concentration gradients. Experimental studies discovered a number of mechanisms for the formation of such gradients. One of the mechanisms relies on the intracellular shuttling of a protein that interconverts between the two states with different diffusivities, under the action of two enzymes, one of which is localized to the plasma membrane, whereas the second is uniformly distributed in the cytoplasm. Recent work reported an analytical solution for the steady state gradient in this mechanism, obtained in the framework of a one-dimensional reaction-diffusion model. Here, we study the dynamics in this model and derive analytical expressions for the Laplace transforms of the time-dependent concentration profiles in terms of elementary transcendental functions. Inverting these transforms numerically, one can obtain time-dependent concentration profiles of the two forms of the protein.

Analytical Energy Gradients for Excited-State Coupled-Cluster Methods

Science.gov (United States)

Wladyslawski, Mark; Nooijen, Marcel

The equation-of-motion coupled-cluster (EOM-CC) and similarity transformed equation-of-motion coupled-cluster (STEOM-CC) methods have been firmly established as accurate and routinely applicable extensions of single-reference coupled-cluster theory to describe electronically excited states. An overview of these methods is provided, with emphasis on the many-body similarity transform concept that is the key to a rationalization of their accuracy. The main topic of the paper is the derivation of analytical energy gradients for such non-variational electronic structure approaches, with an ultimate focus on obtaining their detailed algebraic working equations. A general theoretical framework using Lagrange's method of undetermined multipliers is presented, and the method is applied to formulate the EOM-CC and STEOM-CC gradients in abstract operator terms, following the previous work in [P.G. Szalay, Int. J. Quantum Chem. 55 (1995) 151] and [S.R. Gwaltney, R.J. Bartlett, M. Nooijen, J. Chem. Phys. 111 (1999) 58]. Moreover, the systematics of the Lagrange multiplier approach is suitable for automation by computer, enabling the derivation of the detailed derivative equations through a standardized and direct procedure. To this end, we have developed the SMART (Symbolic Manipulation and Regrouping of Tensors) package of automated symbolic algebra routines, written in the Mathematica programming language. The SMART toolkit provides the means to expand, differentiate, and simplify equations by manipulation of the detailed algebraic tensor expressions directly. The Lagrangian multiplier formulation establishes a uniform strategy to perform the automated derivation in a standardized manner: A Lagrange multiplier functional is constructed from the explicit algebraic equations that define the energy in the electronic method; the energy functional is then made fully variational with respect to all of its parameters, and the symbolic differentiations directly yield the explicit

Migration of inclusions in solids in stress gradients

International Nuclear Information System (INIS)

Olander, D.R.

1980-01-01

A theoretical method of assessing the influence of stress and temperature gradients on the motion of inclusions in solids is developed. In nonuniform stress fields, the stress distribution on the surface of the cavity must be calculated and transformed to a potential gradient for driving a surface atom flux. The bubble migration velocity is the first Legendre coefficient of the surface flux. Higher order components represent distortion. The stress gradient effect appears only in small-magnitude terms in the surface chemical potential, specifically in the stress effect on the solid atomic volume and in the elastic energy density. The migration velocities of spherical and faceted bubbles in solids are computed and the extent of distortion of a spherical bubble is estimated. The role of vacancy exchange with the bulk solid on the migration velocity is assessed. (author)

Variable high gradient permanent magnet quadrupole (QUAPEVA)

Science.gov (United States)

Marteau, F.; Ghaith, A.; N'Gotta, P.; Benabderrahmane, C.; Valléau, M.; Kitegi, C.; Loulergue, A.; Vétéran, J.; Sebdaoui, M.; André, T.; Le Bec, G.; Chavanne, J.; Vallerand, C.; Oumbarek, D.; Cosson, O.; Forest, F.; Jivkov, P.; Lancelot, J. L.; Couprie, M. E.

2017-12-01

Different applications such as laser plasma acceleration, colliders, and diffraction limited light sources require high gradient quadrupoles, with strength that can reach up to 200 T/m for a typical 10 mm bore diameter. We present here a permanent magnet based quadrupole (so-called QUAPEVA) composed of a Halbach ring and surrounded by four permanent magnet cylinders. Its design including magnetic simulation modeling enabling us to reach 201 T/m with a gradient variability of 45% and mechanical issues are reported. Magnetic measurements of seven systems of different lengths are presented and confirmed the theoretical expectations. The variation of the magnetic center while changing the gradient strength is ±10 μm. A triplet of QUAPEVA magnets is used to efficiently focus a beam with large energy spread and high divergence that is generated by a Laser Plasma Acceleration source for a free electron laser demonstration and has enabled us to perform beam based alignment and control the dispersion of the beam.

Half-lives for proton emission, alpha decay, cluster radioactivity, and cold fission processes calculated in a unified theoretical framework

International Nuclear Information System (INIS)

Duarte, S.B.; Tavares, O.A.P.; Guzman, F.; Dimarco, A.; Garcia, F.; Goncalves, M.

2002-01-01

Half-life values of spontaneous nuclear decay processes are presented in the framework of the Effective Liquid Drop Model (ELDM) using the combination of varying mass asymmetry shape description for the mass transfer with Werner-Wheeler's inertia coefficient V MAS /WW. The calculated half-lives of ground-state to ground-state transitions for the proton emission, alpha decay, cluster radioactivity, and cold fission processes are compared with experimental data. Results have shown that the ELDM is a very efficient model to describe these different decay processes in a same, unified theoretical framework. A Table listing the predicted half-life values, τ c is presented for all possible cases of spontaneous nuclear break-up such that -7.30 10 τ c [S] 10 (τ/τ c ) > -17.0, where τ is the total half-life of the parent nucleus. (author)

Using Bourdieu’s Theoretical Framework to Examine How the Pharmacy Educator Views Pharmacy Knowledge

Science.gov (United States)

2015-01-01

Objective. To explore how different pharmacy educators view pharmacy knowledge within the United Kingdom MPharm program and to relate these findings to Pierre Bourdieu’s theoretical framework. Methods. Twelve qualitative interviews were conducted with 4 faculty members from 3 different types of schools of pharmacy in the United Kingdom: a newer school, an established teaching-based school, and an established research-intensive school. Selection was based on a representation of both science-based and practice-based disciplines, gender balance, and teaching experience. Results. The interview transcripts indicated how these members of the academic community describe knowledge. There was a polarization between science-based and practice-based educators in terms of Bourdieu’s description of field, species of capital, and habitus. Conclusion. A Bourdieusian perspective on the differences among faculty member responses supports our understanding of curriculum integration and offers some practical implications for the future development of pharmacy programs. PMID:26889065

Institutional and structural barriers to HIV testing: elements for a theoretical framework.

Science.gov (United States)

Meyerson, Beth; Barnes, Priscilla; Emetu, Roberta; Bailey, Marlon; Ohmit, Anita; Gillespie, Anthony

2014-01-01

Stigma is a barrier to HIV health seeking, but little is known about institutional and structural expressions of stigma in HIV testing. This study examines evidence of institutional and structural stigma in the HIV testing process. A qualitative, grounded theory study was conducted using secondary data from a 2011 HIV test site evaluation data in a Midwestern, moderate HIV incidence state. Expressions of structural and institutional stigma were found with over half of the testing sites and at three stages of the HIV testing visit. Examples of structural stigma included social geography, organization, and staff behavior at first encounter and reception, and staff behavior when experiencing the actual HIV test. Institutional stigma was socially expressed through staff behavior at entry/reception and when experiencing the HIV test. The emerging elements demonstrate the potential compounding of stigma experiences with deleterious effect. Study findings may inform future development of a theoretical framework. In practice, findings can guide organizations seeking to reduce HIV testing barriers, as they provide a window into how test seekers experience HIV test sites at first encounter, entry/reception, and at testing stages; and can identify how stigma might be intensified by structural and institutional expressions.

Comparative Studies of High-Gradient Rf and Dc Breakdowns

CERN Document Server

Kovermann, Jan Wilhelm; Wuensch, Walter

2010-01-01

The CLIC project is based on normal-conducting high-gradient accelerating structures with an average accelerating gradient of 100 MV/m. The maximum achievable gradient in these structures is limited by the breakdown phenomenon. The physics of breakdowns is not yet fully understood quantitatively. A full knowledge could have strong impact on the design, material choice and construction of rf structures. Therefore, understanding breakdowns has great importance to reaching a gradient of 100MV/m with an acceptable breakdown probability. This thesis addresses the physics underlying the breakdown effect, focusing on a comparison of breakdowns in rf structures and in a dc spark setup. The dc system is simpler, easier to benchmark against simulations, with a faster turnaround time, but the relationship to rf breakdown must be established. To do so, an experimental approach based on optical diagnostics and electrical measurements methods was made. Following an introduction into the CLIC project, a general theoretical ...

A trait-based framework for stream algal communities.

Science.gov (United States)

Lange, Katharina; Townsend, Colin Richard; Matthaei, Christoph David

2016-01-01

The use of trait-based approaches to detect effects of land use and climate change on terrestrial plant and aquatic phytoplankton communities is increasing, but such a framework is still needed for benthic stream algae. Here we present a conceptual framework of morphological, physiological, behavioural and life-history traits relating to resource acquisition and resistance to disturbance. We tested this approach by assessing the relationships between multiple anthropogenic stressors and algal traits at 43 stream sites. Our "natural experiment" was conducted along gradients of agricultural land-use intensity (0-95% of the catchment in high-producing pasture) and hydrological alteration (0-92% streamflow reduction resulting from water abstraction for irrigation) as well as related physicochemical variables (total nitrogen concentration and deposited fine sediment). Strategic choice of study sites meant that agricultural intensity and hydrological alteration were uncorrelated. We studied the relationships of seven traits (with 23 trait categories) to our environmental predictor variables using general linear models and an information-theoretic model-selection approach. Life form, nitrogen fixation and spore formation were key traits that showed the strongest relationships with environmental stressors. Overall, FI (farming intensity) exerted stronger effects on algal communities than hydrological alteration. The large-bodied, non-attached, filamentous algae that dominated under high farming intensities have limited dispersal abilities but may cope with unfavourable conditions through the formation of spores. Antagonistic interactions between FI and flow reduction were observed for some trait variables, whereas no interactions occurred for nitrogen concentration and fine sediment. Our conceptual framework was well supported by tests of ten specific hypotheses predicting effects of resource supply and disturbance on algal traits. Our study also shows that investigating a

Human impact gradient on mammalian biodiversity

Directory of Open Access Journals (Sweden)

Mariana Munguía

2016-04-01

Full Text Available Drastic changes have been caused by human influence in natural landscapes, which may exert an intensive effect on species loss. However, species loss from human pressure is not random but depends on a series of environmentally associated factors. Linking species traits to environmental attributes may allow us to detect the ecological impacts of habitat so that meaningful habitat degradation gradients can be identified. The relationships between environmental factors and species traits provide the basis for identifying those biological traits that make species more sensitive to disturbance. These relationships are also helpful to detect the geographic distribution of latent risk to reveal areas where biodiversity is threatened. Here, we identify a “Human Impact Gradient for Biodiversity (HIGB” based on a three-table ordination method (RLQ analysis and fourth-corner analysis to identify key species traits that are associated with environmental gradient. Species distribution and environmental geographic data were gathered nationwide to analyze 68 localities, which represent 27% of Mexico’s surface, including 211 species of mammals. Nine environmental variables (including biophysical, geophysical and land-use impacts were analyzed by using the Geographic Information System. Three types of species’ traits were evaluated: locomotion, trophic habit and body size. We identified a human impact gradient, which was mainly determined by the percentage of the area that was covered by seedlings, the plant richness, the understory coverage percentage and the human settlement index. The most important species traits that are associated with non-human-impacted sites were carnivores, frugivores–herbivores and a body size that was greater than 17.8 kg; 25 species were selected by the decision criteria framework for species that were sensitive to degradation based on ecological function information. Conversely, granivores, fossorial and semifossorial

Predictors of older adults' personal and community mobility: using a comprehensive theoretical mobility framework.

Science.gov (United States)

Umstattd Meyer, M Renée; Janke, Megan C; Beaujean, A Alexander

2014-06-01

Forty-six percent of older adults report limitations in their mobility, and maintaining mobility is considered an important factor in keeping adults independent and active in later life. This study tests a comprehensive theoretical framework of mobility (Webber, S. C., Porter, M. M., & Menec, V. H. [2010]. Mobility in older adults: A comprehensive framework. The Gerontologist, 50[4], 443-450. doi:10.1093/geront/gnq013) identifying multiple determinants that additively influence mobility (financial, psychosocial, environmental, physical, and cognitive), as well as cross-cutting influences of gender, culture, and biography. Structural equation modeling was used to examine several models of mobility using data from 6,112 respondents in the Health and Retirement Study (mean age: 74.74, 85% white, 41% male, 57% married). The original measurement model fit the data well. When both personal and community mobility were simultaneously predicted, only the physical, cognitive, psychosocial, and environmental determinants were retained in the independent models. Age and marital status also predicted personal and community mobility. Although most of these relationships were in the expected direction, interestingly when both forms of mobility were included in the model, poorer cognitive ability was associated with greater personal mobility in the final model. Results indicate the importance of accounting for and examining comprehensive models of mobility. The factors affecting older adults' mobility are complex, and these relationships need to be explored in more depth to ensure the maintenance of individuals' independence and quality of life.

Using a fuzzy comprehensive evaluation method to determine product usability: A proposed theoretical framework.

Science.gov (United States)

Zhou, Ronggang; Chan, Alan H S

2017-01-01

In order to compare existing usability data to ideal goals or to that for other products, usability practitioners have tried to develop a framework for deriving an integrated metric. However, most current usability methods with this aim rely heavily on human judgment about the various attributes of a product, but often fail to take into account of the inherent uncertainties in these judgments in the evaluation process. This paper presents a universal method of usability evaluation by combining the analytic hierarchical process (AHP) and the fuzzy evaluation method. By integrating multiple sources of uncertain information during product usability evaluation, the method proposed here aims to derive an index that is structured hierarchically in terms of the three usability components of effectiveness, efficiency, and user satisfaction of a product. With consideration of the theoretical basis of fuzzy evaluation, a two-layer comprehensive evaluation index was first constructed. After the membership functions were determined by an expert panel, the evaluation appraisals were computed by using the fuzzy comprehensive evaluation technique model to characterize fuzzy human judgments. Then with the use of AHP, the weights of usability components were elicited from these experts. Compared to traditional usability evaluation methods, the major strength of the fuzzy method is that it captures the fuzziness and uncertainties in human judgments and provides an integrated framework that combines the vague judgments from multiple stages of a product evaluation process.

Composition gradients across spiral galaxies II. The stellar mass limit

International Nuclear Information System (INIS)

Shields, G.A.; Tinsley, B.M.

1976-01-01

The equivalent width of the Hβ emission from H ii regions in spiral galaxies increases with distance from the nucleus. This W (Hβ) gradient is interpreted in terms of a radial gradient in the temperature of the hottest exciting stars. (T/subu/). From Searle's observations of M101, an increase Δ log T/subu/=0.02--0.13 from the intermediate to outermost spiral arms of M101 is inferred. There is also a radial decrease in the metal abundance (Z) across M101, and the T/subu/ gradient is consistent with the prediction of Kahn's recent theory that the upper mass limit for star formation should be smaller in regions of high Z. It is noted also that, even in the absence of changes in the upper mass limit, a T/subu/ gradient is expected because metal-rich stars of given mass have smaller effective temperatures. Several observational and theoretical improvements are needed before firm conclusions can be drawn, but it is clear that the presence of a T/subu/ gradient may lead to several important systematic changes in the interpretation of gradients in the properties of H ii regions across galaxies. A T/subu/ gradient reduces the Z gradient that is inferred from emission-line ratios, and it may help to explain why O ii is strong in the innermost regions where O iii is weak. A T/subu/ gradient may also partly camouflage a helium abundance gradient

Application of a theoretical framework to foster a cardiac-diabetes self-management programme.

Science.gov (United States)

Wu, C-J Jo; Chang, A M

2014-09-01

This paper analyses and illustrates the application of Bandura's self-efficacy construct to an innovative self-management programme for patients with both type 2 diabetes and coronary heart disease. Using theory as a framework for any health intervention provides a solid and valid foundation for aspects of planning and delivering such an intervention; however, it is reported that many health behaviour intervention programmes are not based upon theory and are consequently limited in their applicability to different populations. The cardiac-diabetes self-management programme has been specifically developed for patients with dual conditions with the strategies for delivering the programme based upon Bandura's self-efficacy theory. This patient group is at greater risk of negative health outcomes than that with a single chronic condition and therefore requires appropriate intervention programmes with solid theoretical foundations that can address the complexity of care required. The cardiac-diabetes self-management programme has been developed incorporating theory, evidence and practical strategies. This paper provides explicit knowledge of the theoretical basis and components of a cardiac-diabetes self-management programme. Such detail enhances the ability to replicate or adopt the intervention in similar or differing populations and/or cultural contexts as it provides in-depth understanding of each element within the intervention. Knowledge of the concepts alone is not sufficient to deliver a successful health programme. Supporting patients to master skills of self-care is essential in order for patients to successfully manage two complex, chronic illnesses. Valuable information has been provided to close the theory-practice gap for more consistent health outcomes, engaging with patients for promoting holistic care within organizational and cultural contexts. © 2014 International Council of Nurses.

On Scalable Deep Learning and Parallelizing Gradient Descent

CERN Document Server

AUTHOR|(CDS)2129036; Möckel, Rico; Baranowski, Zbigniew; Canali, Luca

Speeding up gradient based methods has been a subject of interest over the past years with many practical applications, especially with respect to Deep Learning. Despite the fact that many optimizations have been done on a hardware level, the convergence rate of very large models remains problematic. Therefore, data parallel methods next to mini-batch parallelism have been suggested to further decrease the training time of parameterized models using gradient based methods. Nevertheless, asynchronous optimization was considered too unstable for practical purposes due to a lacking understanding of the underlying mechanisms. Recently, a theoretical contribution has been made which defines asynchronous optimization in terms of (implicit) momentum due to the presence of a queuing model of gradients based on past parameterizations. This thesis mainly builds upon this work to construct a better understanding why asynchronous optimization shows proportionally more divergent behavior when the number of parallel worker...

Geomorphic controls on elevational gradients of species richness.

Science.gov (United States)

Bertuzzo, Enrico; Carrara, Francesco; Mari, Lorenzo; Altermatt, Florian; Rodriguez-Iturbe, Ignacio; Rinaldo, Andrea

2016-02-16

Elevational gradients of biodiversity have been widely investigated, and yet a clear interpretation of the biotic and abiotic factors that determine how species richness varies with elevation is still elusive. In mountainous landscapes, habitats at different elevations are characterized by different areal extent and connectivity properties, key drivers of biodiversity, as predicted by metacommunity theory. However, most previous studies directly correlated species richness to elevational gradients of potential drivers, thus neglecting the interplay between such gradients and the environmental matrix. Here, we investigate the role of geomorphology in shaping patterns of species richness. We develop a spatially explicit zero-sum metacommunity model where species have an elevation-dependent fitness and otherwise neutral traits. Results show that ecological dynamics over complex terrains lead to the null expectation of a hump-shaped elevational gradient of species richness, a pattern widely observed empirically. Local species richness is found to be related to the landscape elevational connectivity, as quantified by a newly proposed metric that applies tools of complex network theory to measure the closeness of a site to others with similar habitat. Our theoretical results suggest clear geomorphic controls on elevational gradients of species richness and support the use of the landscape elevational connectivity as a null model for the analysis of the distribution of biodiversity.

Systemic Functional Linguistics (SFL as Sociolinguistic and Sociological Conception: Possibilities and Limits of Theoretical Framework

Directory of Open Access Journals (Sweden)

Mariia Rubtcova

2016-05-01

Full Text Available The paper aims at examining possibilities and limits of Systemic functional linguistics theoretical framework. Ideologically SFL concept was associated with the ideas of social justice and equality, the building of the society of equal opportunities through the educational system. The most interesting ideas arose when the SFL representatives thought about the development of English as a native language and were connected with the overcoming of class distinctions. The current version - genre-based approach – has serious limits. The desire of a genre-based approach to the systematization of genres carries a risk of cultural contradictions and conflict of cultures. However, the basic theoretical SFL principles are still in the stage of formation, as SFL researchers seek to avoid some rigidity of the classical institutional (genre approach, which is in contradiction with the principles of diversity. The founder M. Halliday offered ideas for the organization of a flexible approach based on International English that may become World Englishes, developing in order to adapt to the meanings of other cultures.  Therefore, an SFL approach still needs some alterations to spread outside the Western world and conform to the new culture for it. Besides, we can think about proposals of Halliday’s supporters to develop the own version of English for non-Western countries, considering its culture and mentality.

An incremental flow theory for crystal plasticity incorporating strain gradient effects

DEFF Research Database (Denmark)

Nellemann, Christopher; Niordson, Christian Frithiof; Nielsen, Kim Lau

2017-01-01

The present work investigates a new approach to formulating a rate-independent strain gradient theory for crystal plasticity. The approach takes as offset recent discussions published in the literature for isotropic plasticity, and a key ingredient of the present work is the manner in which...... a gradient enhanced effective slip measure governs hardening evolution. The effect of both plastic strains and plastic strain gradients are combined into this scalar effective slip quantity, the energy associated with plastic strain is dissipative (unrecoverable), while the energy from plastic strain...... gradients is recoverable (free). The framework developed forms the basis of a finite element implementation and is demonstrated on benchmark problems designed to bring out effects such as strengthening and hardening. Monotonic loading and plane strain deformation is assumed throughout, but despite this, non...

A study of gradient strengthening based on a finite-deformation gradient crystal-plasticity model

Science.gov (United States)

Pouriayevali, Habib; Xu, Bai-Xiang

2017-11-01

A comprehensive study on a finite-deformation gradient crystal-plasticity model which has been derived based on Gurtin's framework (Int J Plast 24:702-725, 2008) is carried out here. This systematic investigation on the different roles of governing components of the model represents the strength of this framework in the prediction of a wide range of hardening behaviors as well as rate-dependent and scale-variation responses in a single crystal. The model is represented in the reference configuration for the purpose of numerical implementation and then implemented in the FEM software ABAQUS via a user-defined subroutine (UEL). Furthermore, a function of accumulation rates of dislocations is employed and viewed as a measure of formation of short-range interactions. Our simulation results reveal that the dissipative gradient strengthening can be identified as a source of isotropic-hardening behavior, which may represent the effect of irrecoverable work introduced by Gurtin and Ohno (J Mech Phys Solids 59:320-343, 2011). Here, the variation of size dependency at different magnitude of a rate-sensitivity parameter is also discussed. Moreover, an observation of effect of a distinctive feature in the model which explains the effect of distortion of crystal lattice in the reference configuration is reported in this study for the first time. In addition, plastic flows in predefined slip systems and expansion of accumulation of GNDs are distinctly observed in varying scales and under different loading conditions.

A Theoretical Framework for the Studio as a Learning Environment

Science.gov (United States)

Brandt, Carol B.; Cennamo, Katherine; Douglas, Sarah; Vernon, Mitzi; McGrath, Margarita; Reimer, Yolanda

2013-01-01

In this article we describe a holistic, ecological framework that takes into account the surface structures and pedagogical approaches in the studio and how these elements are connected to the construction of design knowledge: epistemology. In our development of this framework, we came to understand how disciplinary underpinnings and academic…

Creating spaces for Eziko Sipheka Sisophula theoretical framework ...

African Journals Online (AJOL)

Within the academy, science and theories have historically been constructed in ways that maintain and privilege the centrality, superiority, legitimacy and universality of western thinking as 'regimes of truth'. The theoretical value of indigenous theories and science has often been denied because theorizing has been ...

Minimum weight protection - Gradient method; Protection de poids minimum - Methode du gradient

Energy Technology Data Exchange (ETDEWEB)

Danon, R.

1958-12-15

After having recalled that, when considering a mobile installation, total weight has a crucial importance, and that, in the case of a nuclear reactor, a non neglectable part of weight is that of protection, this note presents an iterative method which results, for a given protection, to a configuration with a minimum weight. After a description of the problem, the author presents the theoretical formulation of the gradient method as it is applied to the concerned case. This application is then discussed, as well as its validity in terms of convergence and uniqueness. Its actual application is then reported, and possibilities of practical applications are evoked.

Patient centredness in integrated care: results of a qualitative study based on a systems theoretical framework

Directory of Open Access Journals (Sweden)

Daniel Lüdecke

2014-11-01

Full Text Available Introduction: Health care providers seek to improve patient-centred care. Due to fragmentation of services, this can only be achieved by establishing integrated care partnerships. The challenge is both to control costs while enhancing the quality of care and to coordinate this process in a setting with many organisations involved. The problem is to establish control mechanisms, which ensure sufficiently consideration of patient centredness. Theory and methods: Seventeen qualitative interviews have been conducted in hospitals of metropolitan areas in northern Germany. The documentary method, embedded into a systems theoretical framework, was used to describe and analyse the data and to provide an insight into the specific perception of organisational behaviour in integrated care. Results: The findings suggest that integrated care partnerships rely on networks based on professional autonomy in the context of reliability. The relationships of network partners are heavily based on informality. This correlates with a systems theoretical conception of organisations, which are assumed autonomous in their decision-making. Conclusion and discussion: Networks based on formal contracts may restrict professional autonomy and competition. Contractual bindings that suppress the competitive environment have negative consequences for patient-centred care. Drawbacks remain due to missing self-regulation of the network. To conclude, less regimentation of integrated care partnerships is recommended.

Patient centredness in integrated care: results of a qualitative study based on a systems theoretical framework

Directory of Open Access Journals (Sweden)

Daniel Lüdecke

2014-11-01

Full Text Available Introduction: Health care providers seek to improve patient-centred care. Due to fragmentation of services, this can only be achieved by establishing integrated care partnerships. The challenge is both to control costs while enhancing the quality of care and to coordinate this process in a setting with many organisations involved. The problem is to establish control mechanisms, which ensure sufficiently consideration of patient centredness.Theory and methods: Seventeen qualitative interviews have been conducted in hospitals of metropolitan areas in northern Germany. The documentary method, embedded into a systems theoretical framework, was used to describe and analyse the data and to provide an insight into the specific perception of organisational behaviour in integrated care.Results: The findings suggest that integrated care partnerships rely on networks based on professional autonomy in the context of reliability. The relationships of network partners are heavily based on informality. This correlates with a systems theoretical conception of organisations, which are assumed autonomous in their decision-making.Conclusion and discussion: Networks based on formal contracts may restrict professional autonomy and competition. Contractual bindings that suppress the competitive environment have negative consequences for patient-centred care. Drawbacks remain due to missing self-regulation of the network. To conclude, less regimentation of integrated care partnerships is recommended.

Testing thermal gradient driving force for grain boundary migration using molecular dynamics simulations

International Nuclear Information System (INIS)

Bai, Xian-Ming; Zhang, Yongfeng; Tonks, Michael R.

2015-01-01

Strong thermal gradients in low-thermal-conductivity ceramics may drive extended defects, such as grain boundaries and voids, to migrate in preferential directions. In this work, molecular dynamics simulations are conducted to study thermal gradient driven grain boundary migration and to verify a previously proposed thermal gradient driving force equation, using uranium dioxide as a model system. It is found that a thermal gradient drives grain boundaries to migrate up the gradient and the migration velocity increases under a constant gradient owing to the increase in mobility with temperature. Different grain boundaries migrate at very different rates due to their different intrinsic mobilities. The extracted mobilities from the thermal gradient driven simulations are compared with those calculated from two other well-established methods and good agreement between the three different methods is found, demonstrating that the theoretical equation of the thermal gradient driving force is valid, although a correction of one input parameter should be made. The discrepancy in the grain boundary mobilities between modeling and experiments is also discussed.

Firm heterogeneity, investment, and industry expansion: a theoretical framework and the case of the uranium industry

International Nuclear Information System (INIS)

Cohen, W.M.

1981-01-01

The distinguishing feature of this investment analysis is its consideration of firm-specific variables. The theoretical section proposes that firm investment and, in turn, industry expansion are determined by firm-specific corporate variables in addition to the typically considered variables characterizing the firm's experience and expected conditions in a given market, such as rate of growth of demand, price, cost of capital, degree of utilization of capacity, etc. The framework is applied to the uranium mining and milling industry. Descriptive analysis is used to trace the history of the uranium industry in aggregate terms and also as an evolving roster of participating firms with different attributes. The market structure of the industry is also examined. The corporate variables framework is tested statistically in a single-equation, fixed-effects model of uranium exploration behavior, estimated on pooled cross section and time-series data. The postulated corporate variables, except internal firm structure, are combined with market variables in a model which attempts to explain the exploration behavior of 24 firms in the uranium industry from 1973 through 1979. The results indicate that cash flow and exploration expertise influence firms' level of exploration effort. However, differences among firms' intermarket investment strategies do not differentiate the magnitude of their exploration programs

Influence of permittivity on gradient force exerted on Mie spheres.

Science.gov (United States)

Chen, Jun; Li, Kaikai; Li, Xiao

2018-04-01

In optical trapping, whether a particle could be stably trapped into the focus region greatly depends on the strength of the gradient force. Individual theoretical study on gradient force exerted on a Mie particle is rare because the mathematical separation of the gradient force and the scattering force in the Mie regime is difficult. Based on the recent forces separation work by Du et al. [Sci. Rep.7, 18042 (2017)SRCEC32045-232210.1038/s41598-017-17874-1], we investigate the influence of permittivity (an important macroscopic physical quantity) on the gradient force exerted on a Mie particle by cooperating numerical calculation using fast Fourier transform and analytical analysis using multipole expansion. It is revealed that gradient forces exerted on small spheres are mainly determined by the electric dipole moment except for certain permittivity with which the real part of polarizability of the electric dipole approaches zero, and gradient forces exerted on larger spheres are complex because of the superposition of the multipole moments. The classification of permittivity corresponding to different varying tendencies of gradient forces exerted on small spheres or larger Mie particles are illustrated. Absorption of particles favors the trapping of small spheres by gradient force, while it is bad for the trapping of larger particles. Moreover, the absolute values of the maximal gradient forces exerted on larger Mie particles decline greatly versus the varied imaginary part of permittivity. This work provides elaborate investigation on the different varying tendencies of gradient forces versus permittivity, which favors more accurate and free optical trapping.

Reflection and absorption of ion-acoustic waves in a plasma density gradient

International Nuclear Information System (INIS)

Ishihara, O.

1977-01-01

Plasma is characterized by electrical quasineutrality and the collective behavior. There exists a longitudinal low-frequency wave called an ion-acoustic wave in a plasma. One problem in the experimental study of ion-acoustic waves has been that sometimes they are observed to be reflected from discharge tube walls, and sometimes to be absorbed. Theoretical computation reveals that a velocity gradient produced by a density gradient plays a significant role in the reflection. The velocity gradient produces the subsonic-supersonic transition and long wavelength waves are reflected before reaching the transition while short wavelength waves penetrate over the transition and are absorbed in the supersonic flow plasma

Fear of cancer recurrence: a theoretical review and novel cognitive processing formulation

NARCIS (Netherlands)

Fardell, J.E.; Thewes, B.; Turner, J.; Gilchrist, J.; Sharpe, L.; Smith, A.; Girgis, A.; Butow, P.

2016-01-01

PURPOSE: Fear of cancer recurrence (FCR) is prevalent among survivors. However, a comprehensive and universally accepted theoretical framework of FCR to guide intervention is lacking. This paper reviews theoretical frameworks previously used to explain FCR and describes the formulation of a novel

Prototyping high-gradient mm-wave accelerating structures

International Nuclear Information System (INIS)

Nanni, Emilio A.; Dolgashev, Valery A.; Haase, Andrew; Neilson, Jeffrey; Tantawi, Sami

2017-01-01

We present single-cell accelerating structures designed for high-gradient testing at 110 GHz. The purpose of this work is to study the basic physics of ultrahigh vacuum RF breakdown in high-gradient RF accelerators. The accelerating structures are π-mode standing-wave cavities fed with a TM 01 circular waveguide. The structures are fabricated using precision milling out of two metal blocks, and the blocks are joined with diffusion bonding and brazing. The impact of fabrication and joining techniques on the cell geometry and RF performance will be discussed. First prototypes had a measured Q 0 of 2800, approaching the theoretical design value of 3300. The geometry of these accelerating structures are as close as practical to singlecell standing-wave X-band accelerating structures more than 40 of which were tested at SLAC. This wealth of X-band data will serve as a baseline for these 110 GHz tests. Furthermore, the structures will be powered with short pulses from a MW gyrotron oscillator. RF power of 1 MW may allow an accelerating gradient of 400 MeV/m to be reached.

Developing a targeted, theory-informed implementation intervention using two theoretical frameworks to address health professional and organisational factors: a case study to improve the management of mild traumatic brain injury in the emergency department.

Science.gov (United States)

Tavender, Emma J; Bosch, Marije; Gruen, Russell L; Green, Sally E; Michie, Susan; Brennan, Sue E; Francis, Jill J; Ponsford, Jennie L; Knott, Jonathan C; Meares, Sue; Smyth, Tracy; O'Connor, Denise A

2015-05-25

Despite the availability of evidence-based guidelines for the management of mild traumatic brain injury in the emergency department (ED), variations in practice exist. Interventions designed to implement recommended behaviours can reduce this variation. Using theory to inform intervention development is advocated; however, there is no consensus on how to select or apply theory. Integrative theoretical frameworks, based on syntheses of theories and theoretical constructs relevant to implementation, have the potential to assist in the intervention development process. This paper describes the process of applying two theoretical frameworks to investigate the factors influencing recommended behaviours and the choice of behaviour change techniques and modes of delivery for an implementation intervention. A stepped approach was followed: (i) identification of locally applicable and actionable evidence-based recommendations as targets for change, (ii) selection and use of two theoretical frameworks for identifying barriers to and enablers of change (Theoretical Domains Framework and Model of Diffusion of Innovations in Service Organisations) and (iii) identification and operationalisation of intervention components (behaviour change techniques and modes of delivery) to address the barriers and enhance the enablers, informed by theory, evidence and feasibility/acceptability considerations. We illustrate this process in relation to one recommendation, prospective assessment of post-traumatic amnesia (PTA) by ED staff using a validated tool. Four recommendations for managing mild traumatic brain injury were targeted with the intervention. The intervention targeting the PTA recommendation consisted of 14 behaviour change techniques and addressed 6 theoretical domains and 5 organisational domains. The mode of delivery was informed by six Cochrane reviews. It was delivered via five intervention components : (i) local stakeholder meetings, (ii) identification of local opinion

Half-lives for proton emission, alpha decay, cluster radioactivity, and cold fission processes calculated in a unified theoretical framework

Energy Technology Data Exchange (ETDEWEB)

Duarte, S.B.; Tavares, O.A.P.; Guzman, F.; Dimarco, A. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil); Garcia, F. [Sao Paulo Univ., SP (Brazil). Inst. de Fisica; Universidade Estadual de Santa Cruz, Ilheus, BA (Brazil). Dept. de Ciencias Exatas e Tecnologicas; Rodriguez, O. [Sao Paulo Univ., SP (Brazil). Inst. de Fisica; Instituto Superior de Ciencias e Tecnologia Nucleares, La Habana (Cuba); Goncalves, M. [Instituto de Radioprotecao e Dosimetria (IRD), Rio de Janeiro, RJ (Brazil)

2002-01-01

Half-life values of spontaneous nuclear decay processes are presented in the framework of the Effective Liquid Drop Model (ELDM) using the combination of varying mass asymmetry shape description for the mass transfer with Werner-Wheeler's inertia coefficient V{sub MAS}/WW. The calculated half-lives of ground-state to ground-state transitions for the proton emission, alpha decay, cluster radioactivity, and cold fission processes are compared with experimental data. Results have shown that the ELDM is a very efficient model to describe these different decay processes in a same, unified theoretical framework. A Table listing the predicted half-life values, {tau}{sub c} is presented for all possible cases of spontaneous nuclear break-up such that -7.30 <{approx_equal} log{sub 10} {tau}{sub c} [S] <{approx_equal} 27.50 and log {sub 10}({tau}/{tau}{sub c}) > -17.0, where {tau} is the total half-life of the parent nucleus. (author)

Vulnerability assessment of water resources - Translating a theoretical concept to an operational framework using systems thinking approach in a changing climate: Case study in Ogallala Aquifer

Science.gov (United States)

Anandhi, Aavudai; Kannan, Narayanan

2018-02-01

Water is an essential natural resource. Among many stressors, altered climate is exerting pressure on water resource systems, increasing its demand and creating a need for vulnerability assessments. The overall objective of this study was to develop a novel tool that can translate a theoretical concept (vulnerability of water resources (VWR)) to an operational framework mainly under altered temperature and precipitation, as well as for population change (smaller extent). The developed tool had three stages and utilized a novel systems thinking approach. Stage-1: Translating theoretical concept to characteristics identified from studies; Stage-2: Operationalizing characteristics to methodology in VWR; Stage-3: Utilizing the methodology for development of a conceptual modeling tool for VWR: WR-VISTA (Water Resource Vulnerability assessment conceptual model using Indicators selected by System's Thinking Approach). The specific novelties were: 1) The important characteristics in VWR were identified in Stage-1 (target system, system components, scale, level of detail, data source, frameworks, and indicator); 2) WR-VISTA combined two vulnerability assessments frameworks: the European's Driver-Pressure-State-Impact-Response framework (DPSIR) and the Intergovernmental Panel on Climate Change's framework (IPCC's); and 3) used systems thinking approaches in VWR for indicator selection. The developed application was demonstrated in Kansas (overlying the High Plains region/Ogallala Aquifer, considered the "breadbasket of the world"), using 26 indicators with intermediate level of detail. Our results indicate that the western part of the state is vulnerable from agricultural water use and the eastern part from urban water use. The developed tool can be easily replicated to other regions within and outside the US.

Theoretical numerical analysis a functional analysis framework

CERN Document Server

Atkinson, Kendall

2005-01-01

This textbook prepares graduate students for research in numerical analysis/computational mathematics by giving to them a mathematical framework embedded in functional analysis and focused on numerical analysis. This helps the student to move rapidly into a research program. The text covers basic results of functional analysis, approximation theory, Fourier analysis and wavelets, iteration methods for nonlinear equations, finite difference methods, Sobolev spaces and weak formulations of boundary value problems, finite element methods, elliptic variational inequalities and their numerical solu

Pain judgements of patients' relatives: examining the use of social contract theory as theoretical framework.

Science.gov (United States)

Kappesser, Judith; de C Williams, Amanda C

2008-08-01

Observer underestimation of others' pain was studied using a concept from evolutionary psychology: a cheater detection mechanism from social contract theory, applied to relatives and friends of chronic pain patients. 127 participants estimated characters' pain intensity and fairness of behaviour after reading four vignettes describing characters suffering from pain. Four cues were systematically varied: the character continuing or stopping liked tasks; continuing or stopping disliked tasks; availability of medical evidence; and pain intensity as rated by characters. Results revealed that pain intensity and the two behavioural variables had an effect on pain estimates: high pain self-reports and stopping all tasks led to high pain estimates; pain was estimated to be lowest when characters stopped disliked but continued with liked tasks. This combination was also rated least fair. Results support the use of social contract theory as a theoretical framework to explore pain judgements.

Enhancing early detection of exotic pests in agricultural and forest ecosystems using an urban-gradient framework

Science.gov (United States)

Manuel Colunga-Garcia; Roger A. Magarey; Robert A. Haack; Stuart H. Gage; Jiaquo. Qi

2010-01-01

Urban areas are hubs of international transport and therefore are major gateways for exotic pests. Applying an urban gradient to analyze this pathway could provide insight into the ecological processes involved in human-mediated invasions. We defined an urban gradient for agricultural and forest ecosystems in the contiguous United States to (1) assess whether...

A theoretical framework for analyzing the effect of external change on tidal dynamics in estuaries

Science.gov (United States)

CAI, H.; Savenije, H.; Toffolon, M.

2013-12-01

The most densely populated areas of the world are usually located in coastal areas near estuaries. As a result, estuaries are often subject to intense human interventions, such as dredging for navigation, dam construction and fresh water withdrawal etc., which in some areas has led to serious deterioration of invaluable ecosystems. Hence it is important to understand the influence of such interventions on tidal dynamics in these areas. In this study, we present one consistent theoretical framework for tidal hydrodynamics, which can be used as a rapid assessment technique that assist policy maker and managers to make considered decisions for the protection and management of estuarine environment when assessing the effect of human interventions in estuaries. Analytical solutions to the one-dimensional St. Venant equations for the tidal hydrodynamics in convergent unbounded estuaries with negligible river discharge can be cast in the form of a set of four implicit dimensionless equations for phase lag, velocity amplitude, damping, and wave celerity, as a function of two localized parameters describing friction and convergence. This method allows for the comparison of the different analytical approaches by rewriting the different solutions in the same format. In this study, classical and more recent formulations are compared, showing the differences and similarities associated to their specific simplifications. The envelope method, which is based on the consideration of the dynamics at high water and low water, can be used to derive damping equations that use different friction approximations. This results in as many analytical solutions, and thereby allows one to build a consistent theoretical framework. Analysis of the asymptotic behaviour of the equations shows that an equilibrium tidal amplitude exits reflecting the balance between friction and channel convergence. The framework is subsequently extended to take into account the effect of river discharge. Hence, the

A Game Theoretic Framework for Green HetNets Using D2D Traffic Offload and Renewable Energy Powered Base Stations

KAUST Repository

Yaacoub, Elias

2015-08-26

This chapter investigates the interplay between cooperative device-to-device (D2D) communications and green communications in LTE heterogeneous networks (HetNets). Two game theoretic concepts are studied and analyzed in order to perform dynamic HetNet base station (BS) on/off switching. The first approach is a coalition-based method whereas the second is based on the Nash bargaining solution. Afterwards, a method for coupling the BS on/off switching approach with D2D collaborative communications is presented and shown to lead to increased energy efficiency. The savings are additionally increased when a portion of the small cell BSs in a HetNet are powered by renewable energy sources. Different utility functions, modeling the game theoretic framework governing the energy consumption balance between the cellular network and the mobile terminals (MTs), are proposed and compared, and their impact on MT quality of service (QoS) is analyzed.

A Game Theoretic Framework for Green HetNets Using D2D Traffic Offload and Renewable Energy Powered Base Stations

KAUST Repository

Yaacoub, Elias; Ghazzai, Hakim; Alouini, Mohamed-Slim

2015-01-01

This chapter investigates the interplay between cooperative device-to-device (D2D) communications and green communications in LTE heterogeneous networks (HetNets). Two game theoretic concepts are studied and analyzed in order to perform dynamic HetNet base station (BS) on/off switching. The first approach is a coalition-based method whereas the second is based on the Nash bargaining solution. Afterwards, a method for coupling the BS on/off switching approach with D2D collaborative communications is presented and shown to lead to increased energy efficiency. The savings are additionally increased when a portion of the small cell BSs in a HetNet are powered by renewable energy sources. Different utility functions, modeling the game theoretic framework governing the energy consumption balance between the cellular network and the mobile terminals (MTs), are proposed and compared, and their impact on MT quality of service (QoS) is analyzed.

A study of microindentation hardness tests by mechanism-based strain gradient plasticity

International Nuclear Information System (INIS)

Huang, Y.; Xue, Z.; Gao, H.; Nix, W. D.; Xia, Z. C.

2000-01-01

We recently proposed a theory of mechanism-based strain gradient (MSG) plasticity to account for the size dependence of plastic deformation at micron- and submicron-length scales. The MSG plasticity theory connects micron-scale plasticity to dislocation theories via a multiscale, hierarchical framework linking Taylor's dislocation hardening model to strain gradient plasticity. Here we show that the theory of MSG plasticity, when used to study micro-indentation, indeed reproduces the linear dependence observed in experiments, thus providing an important self-consistent check of the theory. The effects of pileup, sink-in, and the radius of indenter tip have been taken into account in the indentation model. In accomplishing this objective, we have generalized the MSG plasticity theory to include the elastic deformation in the hierarchical framework. (c) 2000 Materials Research Society

Reflectance analysis of porosity gradient in nanostructured silicon layers

Science.gov (United States)

Jurečka, Stanislav; Imamura, Kentaro; Matsumoto, Taketoshi; Kobayashi, Hikaru

2017-12-01

In this work we study optical properties of nanostructured layers formed on silicon surface. Nanostructured layers on Si are formed in order to reach high suppression of the light reflectance. Low spectral reflectance is important for improvement of the conversion efficiency of solar cells and for other optoelectronic applications. Effective method of forming nanostructured layers with ultralow reflectance in a broad interval of wavelengths is in our approach based on metal assisted etching of Si. Si surface immersed in HF and H2O2 solution is etched in contact with the Pt mesh roller and the structure of the mesh is transferred on the etched surface. During this etching procedure the layer density evolves gradually and the spectral reflectance decreases exponentially with the depth in porous layer. We analyzed properties of the layer porosity by incorporating the porosity gradient into construction of the layer spectral reflectance theoretical model. Analyzed layer is splitted into 20 sublayers in our approach. Complex dielectric function in each sublayer is computed by using Bruggeman effective media theory and the theoretical spectral reflectance of modelled multilayer system is computed by using Abeles matrix formalism. Porosity gradient is extracted from the theoretical reflectance model optimized in comparison to the experimental values. Resulting values of the structure porosity development provide important information for optimization of the technological treatment operations.

Factors that influence effective perioperative temperature management by anesthesiologists: a qualitative study using the Theoretical Domains Framework.

Science.gov (United States)

Boet, Sylvain; Patey, Andrea M; Baron, Justine S; Mohamed, Karim; Pigford, Ashlee-Ann E; Bryson, Gregory L; Brehaut, Jamie C; Grimshaw, Jeremy M

2017-06-01

Inadvertent perioperative hypothermia (IPH) is associated with a range of adverse outcomes. Safe and effective warming techniques exist to prevent IPH; however, IPH remains common. This study aimed to identify factors that anesthesiologists perceive may influence temperature management during the perioperative period. After Research Ethics Board approval, semi-structured interviews were conducted with staff anesthesiologists at a Canadian academic hospital. An interview guide based on the Theoretical Domains Framework (TDF) was used to capture 14 theoretical domains that may influence temperature management. The interview transcripts were coded using direct content analysis to generate specific beliefs and to identify relevant TDF domains perceived to influence temperature management behaviour. Data saturation was achieved after 15 interviews. The following nine theoretical domains were identified as relevant to designing an intervention for practices in perioperative temperature management: knowledge, beliefs about capabilities, beliefs about consequences, reinforcement, memory/attention/decision-making, environmental context and resources, social/professional role/identity, social influences, and behavioural regulation. Potential target areas to improve temperature management practices include interventions that address information needs about individual temperature management behaviour as well as patient outcome (feedback), increasing awareness of possible temperature management strategies and guidelines, and a range of equipment and surgical team dynamics that influence temperature management. This study identified several potential target areas for future interventions from nine of the TDF behavioural domains that anesthesiologists perceive to drive their temperature management practices. Future interventions that aim to close the evidence-practice gap in perioperative temperature management may include these targets.

A generalized theoretical framework for the description of spin decoupling in solid-state MAS NMR: Offset effect on decoupling performance

Energy Technology Data Exchange (ETDEWEB)

Tan, Kong Ooi; Meier, Beat H., E-mail: beme@ethz.ch, E-mail: maer@ethz.ch; Ernst, Matthias, E-mail: beme@ethz.ch, E-mail: maer@ethz.ch [Physical Chemistry, ETH Zürich, Vladimir-Prelog-Weg 2, 8093 Zürich (Switzerland); Agarwal, Vipin [Physical Chemistry, ETH Zürich, Vladimir-Prelog-Weg 2, 8093 Zürich (Switzerland); TIFR Centre for Interdisciplinary Sciences, 21 Brundavan Colony, Narsinghi, Hyderabad 500 075 (India)

2016-09-07

We present a generalized theoretical framework that allows the approximate but rapid analysis of residual couplings of arbitrary decoupling sequences in solid-state NMR under magic-angle spinning conditions. It is a generalization of the tri-modal Floquet analysis of TPPM decoupling [Scholz et al., J. Chem. Phys. 130, 114510 (2009)] where three characteristic frequencies are used to describe the pulse sequence. Such an approach can be used to describe arbitrary periodic decoupling sequences that differ only in the magnitude of the Fourier coefficients of the interaction-frame transformation. It allows a ∼100 times faster calculation of second-order residual couplings as a function of pulse sequence parameters than full spin-dynamics simulations. By comparing the theoretical calculations with full numerical simulations, we show the potential of the new approach to examine the performance of decoupling sequences. We exemplify the usefulness of this framework by analyzing the performance of commonly used high-power decoupling sequences and low-power decoupling sequences such as amplitude-modulated XiX (AM-XiX) and its super-cycled variant SC-AM-XiX. In addition, the effect of chemical-shift offset is examined for both high- and low-power decoupling sequences. The results show that the cross-terms between the dipolar couplings are the main contributions to the line broadening when offset is present. We also show that the SC-AM-XIX shows a better offset compensation.

A generalized theoretical framework for the description of spin decoupling in solid-state MAS NMR: Offset effect on decoupling performance.

Science.gov (United States)

Tan, Kong Ooi; Agarwal, Vipin; Meier, Beat H; Ernst, Matthias

2016-09-07

We present a generalized theoretical framework that allows the approximate but rapid analysis of residual couplings of arbitrary decoupling sequences in solid-state NMR under magic-angle spinning conditions. It is a generalization of the tri-modal Floquet analysis of TPPM decoupling [Scholz et al., J. Chem. Phys. 130, 114510 (2009)] where three characteristic frequencies are used to describe the pulse sequence. Such an approach can be used to describe arbitrary periodic decoupling sequences that differ only in the magnitude of the Fourier coefficients of the interaction-frame transformation. It allows a ∼100 times faster calculation of second-order residual couplings as a function of pulse sequence parameters than full spin-dynamics simulations. By comparing the theoretical calculations with full numerical simulations, we show the potential of the new approach to examine the performance of decoupling sequences. We exemplify the usefulness of this framework by analyzing the performance of commonly used high-power decoupling sequences and low-power decoupling sequences such as amplitude-modulated XiX (AM-XiX) and its super-cycled variant SC-AM-XiX. In addition, the effect of chemical-shift offset is examined for both high- and low-power decoupling sequences. The results show that the cross-terms between the dipolar couplings are the main contributions to the line broadening when offset is present. We also show that the SC-AM-XIX shows a better offset compensation.

The Consolidated Framework for Implementation Research (CFIR): a useful theoretical framework for guiding and evaluating a guideline implementation process in a hospital-based nursing practice.

Science.gov (United States)

Breimaier, Helga E; Heckemann, Birgit; Halfens, Ruud J G; Lohrmann, Christa

2015-01-01

Implementing clinical practice guidelines (CPGs) in healthcare settings is a complex intervention involving both independent and interdependent components. Although the Consolidated Framework for Implementation Research (CFIR) has never been evaluated in a practical context, it appeared to be a suitable theoretical framework to guide an implementation process. The aim of this study was to evaluate the comprehensiveness, applicability and usefulness of the CFIR in the implementation of a fall-prevention CPG in nursing practice to improve patient care in an Austrian university teaching hospital setting. The evaluation of the CFIR was based on (1) team-meeting minutes, (2) the main investigator's research diary, containing a record of a before-and-after, mixed-methods study design embedded in a participatory action research (PAR) approach for guideline implementation, and (3) an analysis of qualitative and quantitative data collected from graduate and assistant nurses in two Austrian university teaching hospital departments. The CFIR was used to organise data per and across time point(s) and assess their influence on the implementation process, resulting in implementation and service outcomes. Overall, the CFIR could be demonstrated to be a comprehensive framework for the implementation of a guideline into a hospital-based nursing practice. However, the CFIR did not account for some crucial factors during the planning phase of an implementation process, such as consideration of stakeholder aims and wishes/needs when implementing an innovation, pre-established measures related to the intended innovation and pre-established strategies for implementing an innovation. For the CFIR constructs reflecting & evaluating and engaging, a more specific definition is recommended. The framework and its supplements could easily be used by researchers, and their scope was appropriate for the complexity of a prospective CPG-implementation project. The CFIR facilitated qualitative data

Theoretical study of n-alkane adsorption on metal surfaces

DEFF Research Database (Denmark)

Morikawa, Yoshitada; Ishii, Hisao; Seki, Kazuhiko

2004-01-01

The interaction between n-alkane and metal surfaces has been studied by means of density-functional theoretical calculations within a generalized gradient approximation (GGA). We demonstrate that although the GGA cannot reproduce the physisorption energy well, our calculations can reproduce the e...

Theoretical Guidelines for a Psychology of Rural Development

NARCIS (Netherlands)

Landini, F.; Long, N.; Leeuwis, C.; Murtagh, S.

2014-01-01

Many processes related to rural development have a strong psychosocial component. Yet, there exists no specific psychosocial theoretical framework for addressing them. In this paper, then, we present a set of theoretical guidelines for analysing rural development processes and interventions from the

A flexoelectric theory with rotation gradient effects for elastic dielectrics

International Nuclear Information System (INIS)

Anqing, Li; Shenjie, Zhou; Lu, Qi; Xi, Chen

2016-01-01

In this paper, a general flexoelectric theory in the framework of couple stress theory is proposed for isotropic dielectrics, in which the rotation gradient and the polarization gradient are involved to represent the nonlocal mechanical and electrical effects, respectively. The present flexoelectric theory shows only the anti-symmetric part of rotation gradient can induce polarization, while the symmetric part of rotation gradient cannot induce polarization in isotropic dielectrics. The electrostatic stress is obtained naturally in the governing equations and boundary conditions in terms of the variational principle, which is composed of two parts: the Maxwell stress corresponding to the polarization and the remainder relating to the polarization gradient. The current theory is able to account for the effects of size, direct and inverse flexoelectricities, and electrostatic force. To illustrate this theory, a simple application of Bernoulli–Euler cantilever beam is discussed. The numerical results demonstrate neither the higher-order constant l 1 nor the higher-order constant l 2 associated with the symmetric and anti-symmetric parts of rotation gradient, respectively, can be ignored in the flexoelectric theory. In addition, the induced deflection increases as the increase of the flexoelectric coefficient. The polarization is no longer constant and the potential is no longer linear along the thickness direction of beam because of the influence of polarization gradient. (paper)

Adaptive dynamics on an environmental gradient that changes over a geological time-scale.

Science.gov (United States)

Fortelius, Mikael; Geritz, Stefan; Gyllenberg, Mats; Toivonen, Jaakko

2015-07-07

The standard adaptive dynamics framework assumes two timescales, i.e. fast population dynamics and slow evolutionary dynamics. We further assume a third timescale, which is even slower than the evolutionary timescale. We call this the geological timescale and we assume that slow climatic change occurs within this timescale. We study the evolution of our model population over this very slow geological timescale with bifurcation plots of the standard adaptive dynamics framework. The bifurcation parameter being varied describes the abiotic environment that changes over the geological timescale. We construct evolutionary trees over the geological timescale and observe both gradual phenotypic evolution and punctuated branching events. We concur with the established notion that branching of a monomorphic population on an environmental gradient only happens when the gradient is not too shallow and not too steep. However, we show that evolution within the habitat can produce polymorphic populations that inhabit steep gradients. What is necessary is that the environmental gradient at some point in time is such that the initial branching of the monomorphic population can occur. We also find that phenotypes adapted to environments in the middle of the existing environmental range are more likely to branch than phenotypes adapted to extreme environments. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Role of social media discourses on stakeholder crises awareness and perception – A meta-theoretical framework

DEFF Research Database (Denmark)

Valentini, Chiara; Romenti, Stefania; Kruckeberg, Dean

, such perspective is best suited to explain the relationships between publics and organizations in the online environment. According to this perspective, organizations are not the hub of stakeholder communications and interactions, but rather they are simply spikes in a more complex network. Public......This paper provides a meta-theoretical framework to examine social media communications and crisis communication in these social media through the lens of communicative constitution of reality. Our claim is that discourse and online conversations are significant in shaping publics’ opinions...... in social media, both in general and specifically in discussions about crisis situations. Therefore, studying language and discourse becomes paramount to understand how conversations structure relationships and public opinions. We approach this task through a network-based perspective because, we argue...

Gradient descent learning algorithm overview: a general dynamical systems perspective.

Science.gov (United States)

Baldi, P

1995-01-01

Gives a unified treatment of gradient descent learning algorithms for neural networks using a general framework of dynamical systems. This general approach organizes and simplifies all the known algorithms and results which have been originally derived for different problems (fixed point/trajectory learning), for different models (discrete/continuous), for different architectures (forward/recurrent), and using different techniques (backpropagation, variational calculus, adjoint methods, etc.). The general approach can also be applied to derive new algorithms. The author then briefly examines some of the complexity issues and limitations intrinsic to gradient descent learning. Throughout the paper, the author focuses on the problem of trajectory learning.

Multimodal image registration based on binary gradient angle descriptor.

Science.gov (United States)

Jiang, Dongsheng; Shi, Yonghong; Yao, Demin; Fan, Yifeng; Wang, Manning; Song, Zhijian

2017-12-01

Multimodal image registration plays an important role in image-guided interventions/therapy and atlas building, and it is still a challenging task due to the complex intensity variations in different modalities. The paper addresses the problem and proposes a simple, compact, fast and generally applicable modality-independent binary gradient angle descriptor (BGA) based on the rationale of gradient orientation alignment. The BGA can be easily calculated at each voxel by coding the quadrant in which a local gradient vector falls, and it has an extremely low computational complexity, requiring only three convolutions, two multiplication operations and two comparison operations. Meanwhile, the binarized encoding of the gradient orientation makes the BGA more resistant to image degradations compared with conventional gradient orientation methods. The BGA can extract similar feature descriptors for different modalities and enable the use of simple similarity measures, which makes it applicable within a wide range of optimization frameworks. The results for pairwise multimodal and monomodal registrations between various images (T1, T2, PD, T1c, Flair) consistently show that the BGA significantly outperforms localized mutual information. The experimental results also confirm that the BGA can be a reliable alternative to the sum of absolute difference in monomodal image registration. The BGA can also achieve an accuracy of [Formula: see text], similar to that of the SSC, for the deformable registration of inhale and exhale CT scans. Specifically, for the highly challenging deformable registration of preoperative MRI and 3D intraoperative ultrasound images, the BGA achieves a similar registration accuracy of [Formula: see text] compared with state-of-the-art approaches, with a computation time of 18.3 s per case. The BGA improves the registration performance in terms of both accuracy and time efficiency. With further acceleration, the framework has the potential for

Intellectual potential of population: theoretical and methodological framework for research

Directory of Open Access Journals (Sweden)

Galina Valentinovna Leonidova

2014-03-01

Full Text Available The article considers the theoretical and methodological framework for the research into the population’s intellectual potential. The presented materials show that this category is the subject of interdisciplinary studies, including philosophy, psychology, sociology, pedagogics, economics. One of the important conclusions drawn from the analysis of the essence of intellectual potential is the conclusion that the actual level of intelligence is the result of its development. It means that certain efforts on the part of such social institutions like family, education, government, promote not only the formation of smart people, but also the implementation of their potential intellectual capabilities in the production, creation of cultural values, society management, education, etc. when using this approach, the intellect ceases to be just a research object of related disciplines, but it acquires social dimension and becomes a socio-economic category. The basic theories, concepts and approaches, used in its study, were analyzed. The theory of human capital was given a most thorough consideration, because, according to this theory, the income of a person is earned by knowledge, abilities and skills, i.e. the essence of intellectual properties of an individual. The article provides the author’s definition of the intellectual potential of the population, which brings to the fore the following elements necessary for the understanding of this category: relation to socioeconomic development, factors in the formation of the characteristic, including the need for training (reproduction of intelligent people, the psychological aspect (abilities, the carriers of intellectual potential are not ignored, because it is an attribute of the population. The article identifies methodological approaches to the estimation of the population’s intellectual potential, describes the applied procedures and research methods. The authors propose methodological

Random Combinatorial Gradient Metasurface for Broadband, Wide-Angle and Polarization-Independent Diffusion Scattering.

Science.gov (United States)

Zhuang, Yaqiang; Wang, Guangming; Liang, Jiangang; Cai, Tong; Tang, Xiao-Lan; Guo, Tongfeng; Zhang, Qingfeng

2017-11-29

This paper proposes an easy, efficient strategy for designing broadband, wide-angle and polarization-independent diffusion metasurface for radar cross section (RCS) reduction. A dual-resonance unit cell, composed of a cross wire and cross loop (CWCL), is employed to enhance the phase bandwidth covering the 2π range. Both oblique-gradient and horizontal-gradient phase supercells are designed for illustration. The numerical results agree well with the theoretical ones. To significantly reduce backward scattering, the random combinatorial gradient metasurface (RCGM) is subsequently constructed by collecting eight supercells with randomly distributed gradient directions. The proposed metasurface features an enhanced specular RCS reduction performance and less design complexity compared to other candidates. Both simulated and measured results show that the proposed RCGM can significantly suppress RCS and exhibits broadband, wide-angle and polarization independence features.

Demonstration of the usefulness of a theoretical framework for humanising care with reference to a residential aged care service in Australia.

Science.gov (United States)

Borbasi, Sally; Galvin, Kathleen T; Adams, Trevor; Todres, Les; Farrelly, Brona

2013-03-01

To demonstrate the usefulness of a theoretical framework for humanising care of dementia patients. The term humanisation of care has been increasingly used to describe an approach to health care that is informed by core dimensions of what it means to be human. Recent developments in dementia care highlight the importance of maintaining personhood in people with dementia. A conceptual framework is proposed by which the humanisation of care can be understood and applied. Eight dimensions that articulate core features of what needs to be attended to in order for a person to feel more deeply 'met' as a human being are discussed. Evidence from an evaluative study of a dementia outreach service is used to illustrate the usefulness of the humanising framework. Case study examples demonstrate the value of this framework by describing how a dementia outreach service enables care staff in residential aged care facilities to change their focus in the provision of care to residents with dementia. Each of the eight dimensions of humanisation/dehumanisation is used to illustrate how the dementia outreach service team have led to the improvements in resident care. Positive outcomes can be achieved by providing humanised care to residents with dementia. The paper highlights the potential for the humanising framework to be used in dementia care and shows how the framework can be helpfully translated into practice so that carers are supported to adopt an inclusive view of care delivery. A comprehensive framework, grounded in a strong philosophical foundation, can name a breadth of criteria for humanly sensitive care and can be translated into practice in such a way as to potentially transform the provision of care to residents in residential aged care facilities. © 2012 Blackwell Publishing Ltd.

Inform: Efficient Information-Theoretic Analysis of Collective Behaviors

Directory of Open Access Journals (Sweden)

Douglas G. Moore

2018-06-01

Full Text Available The study of collective behavior has traditionally relied on a variety of different methodological tools ranging from more theoretical methods such as population or game-theoretic models to empirical ones like Monte Carlo or multi-agent simulations. An approach that is increasingly being explored is the use of information theory as a methodological framework to study the flow of information and the statistical properties of collectives of interacting agents. While a few general purpose toolkits exist, most of the existing software for information theoretic analysis of collective systems is limited in scope. We introduce Inform, an open-source framework for efficient information theoretic analysis that exploits the computational power of a C library while simplifying its use through a variety of wrappers for common higher-level scripting languages. We focus on two such wrappers here: PyInform (Python and rinform (R. Inform and its wrappers are cross-platform and general-purpose. They include classical information-theoretic measures, measures of information dynamics and information-based methods to study the statistical behavior of collective systems, and expose a lower-level API that allow users to construct measures of their own. We describe the architecture of the Inform framework, study its computational efficiency and use it to analyze three different case studies of collective behavior: biochemical information storage in regenerating planaria, nest-site selection in the ant Temnothorax rugatulus, and collective decision making in multi-agent simulations.

A Quantitative Theoretical Framework For Protein-Induced Fluorescence Enhancement-Förster-Type Resonance Energy Transfer (PIFE-FRET).

Science.gov (United States)

Lerner, Eitan; Ploetz, Evelyn; Hohlbein, Johannes; Cordes, Thorben; Weiss, Shimon

2016-07-07

Single-molecule, protein-induced fluorescence enhancement (PIFE) serves as a molecular ruler at molecular distances inaccessible to other spectroscopic rulers such as Förster-type resonance energy transfer (FRET) or photoinduced electron transfer. In order to provide two simultaneous measurements of two distances on different molecular length scales for the analysis of macromolecular complexes, we and others recently combined measurements of PIFE and FRET (PIFE-FRET) on the single molecule level. PIFE relies on steric hindrance of the fluorophore Cy3, which is covalently attached to a biomolecule of interest, to rotate out of an excited-state trans isomer to the cis isomer through a 90° intermediate. In this work, we provide a theoretical framework that accounts for relevant photophysical and kinetic parameters of PIFE-FRET, show how this framework allows the extraction of the fold-decrease in isomerization mobility from experimental data, and show how these results provide information on changes in the accessible volume of Cy3. The utility of this model is then demonstrated for experimental results on PIFE-FRET measurement of different protein-DNA interactions. The proposed model and extracted parameters could serve as a benchmark to allow quantitative comparison of PIFE effects in different biological systems.

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

Science.gov (United States)

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

2015-09-02

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. © 2015 Diabetes Technology Society.

General approach for solving the density gradient theory in the interfacial tension calculations

DEFF Research Database (Denmark)

Liang, Xiaodong; Michelsen, Michael Locht

2017-01-01

Within the framework of the density gradient theory, the interfacial tension can be calculated by finding the density profiles that minimize an integral of two terms over the system of infinite width. It is found that the two integrands exhibit a constant difference along the interface for a finite...... property evaluations compared to other methods. The performance of the algorithm with recommended parameters is analyzed for various systems, and the efficiency is further compared with the geometric-mean density gradient theory, which only needs to solve nonlinear algebraic equations. The results show...... that the algorithm is only 5-10 times less efficient than solving the geometric-mean density gradient theory....

Validating experimental and theoretical Langmuir probe analyses

Science.gov (United States)

Pilling, L. S.; Carnegie, D. A.

2007-08-01

Analysis of Langmuir probe characteristics contains a paradox in that it is unknown a priori which theory is applicable before it is applied. Often theories are assumed to be correct when certain criteria are met although they may not validate the approach used. We have analysed the Langmuir probe data from cylindrical double and single probes acquired from a dc discharge plasma over a wide variety of conditions. This discharge contains a dual-temperature distribution and hence fitting a theoretically generated curve is impractical. To determine the densities, an examination of the current theories was necessary. For the conditions where the probe radius is the same order of magnitude as the Debye length, the gradient expected for orbital-motion limited (OML) is approximately the same as the radial-motion gradients. An analysis of the 'gradients' from the radial-motion theory was able to resolve the differences from the OML gradient value of two. The method was also able to determine whether radial or OML theories applied without knowledge of the electron temperature, or separation of the ion and electron contributions. Only the value of the space potential is necessary to determine the applicable theory.

On the accurate analysis of vibroacoustics in head insert gradient coils.

Science.gov (United States)

Winkler, Simone A; Alejski, Andrew; Wade, Trevor; McKenzie, Charles A; Rutt, Brian K

2017-10-01

To accurately analyze vibroacoustics in MR head gradient coils. A detailed theoretical model for gradient coil vibroacoustics, including the first description and modeling of Lorentz damping, is introduced and implemented in a multiphysics software package. Numerical finite-element method simulations were used to establish a highly accurate vibroacoustic model in head gradient coils in detail, including the newly introduced Lorentz damping effect. Vibroacoustic coupling was examined through an additional modal analysis. Thorough experimental studies were used to validate simulations. Average experimental sound pressure levels (SPLs) and accelerations over the 0-3000 Hz frequency range were 97.6 dB, 98.7 dB, and 95.4 dB, as well as 20.6 g, 8.7 g, and 15.6 g for the X-, Y-, and Z-gradients, respectively. A reasonable agreement between simulations and measurements was achieved. Vibroacoustic coupling showed a coupled resonance at 2300 Hz for the Z-gradient that is responsible for a sharp peak and the highest SPL value in the acoustic spectrum. We have developed and used more realistic multiphysics simulation methods to gain novel insights into the underlying concepts for vibroacoustics in head gradient coils, which will permit improved analyses of existing gradient coils and novel SPL reduction strategies for future gradient coil designs. Magn Reson Med 78:1635-1645, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

Theoretical aspects of gradient reversed-phase high performance liquid chromatography of styrene-butylacrylate block copolymers

NARCIS (Netherlands)

Kolarova, L.; Jandera, P.; Vonk, E.C.; Claessens, H.A.

2004-01-01

Butylacrylate – styrene co-polymers prepared by atom transfer radical polymeratization were separated on an octadecyl silica column by gradient elution with tetrahydrofuran in water, up to the molar masses 10,000. In reversed-phase high performance liquid chromatography (RP-HPLC), the retention of

Hydrodynamic fabrication of structurally gradient ZnO nanorods.

Science.gov (United States)

Kim, Hyung Min; Youn, Jae Ryoun; Song, Young Seok

2016-02-26

We studied a new approach where structurally gradient nanostructures were fabricated by means of hydrodynamics. Zinc oxide (ZnO) nanorods were synthesized in a drag-driven rotational flow in a controlled manner. The structural characteristics of nanorods such as orientation and diameter were determined by momentum and mass transfer at the substrate surface. The nucleation of ZnO was induced by shear stress which plays a key role in determining the orientation of ZnO nanorods. The nucleation and growth of such nanostructures were modeled theoretically and analyzed numerically to understand the underlying physics of the fabrication of nanostructures controlled by hydrodynamics. The findings demonstrated that the precise control of momentum and mass transfer enabled the formation of ZnO nanorods with a structural gradient in diameter and orientation.

Deformation patterning driven by rate dependent non-convex strain gradient plasticity

NARCIS (Netherlands)

Yalcinkaya, T.; Brekelmans, W.A.M.; Geers, M.G.D.

2011-01-01

A rate dependent strain gradient plasticity framework for the description of plastic slip patterning in a system with non-convex energetic hardening is presented. Both the displacement and the plastic slip fields are considered as primary variables. These fields are determined on a global level by

Analyses of Lattice Traffic Flow Model on a Gradient Highway

International Nuclear Information System (INIS)

Gupta Arvind Kumar; Redhu Poonam; Sharma Sapna

2014-01-01

The optimal current difference lattice hydrodynamic model is extended to investigate the traffic flow dynamics on a unidirectional single lane gradient highway. The effect of slope on uphill/downhill highway is examined through linear stability analysis and shown that the slope significantly affects the stability region on the phase diagram. Using nonlinear stability analysis, the Burgers, Korteweg-deVries (KdV) and modified Korteweg-deVries (mKdV) equations are derived in stable, metastable and unstable region, respectively. The effect of reaction coefficient is examined and concluded that it plays an important role in suppressing the traffic jams on a gradient highway. The theoretical findings have been verified through numerical simulation which confirm that the slope on a gradient highway significantly influence the traffic dynamics and traffic jam can be suppressed efficiently by considering the optimal current difference effect in the new lattice model. (nuclear physics)

Using a Theoretical Framework to Investigate Whether the HIV/AIDS Information Needs of the AfroAIDSinfo Web Portal Members Are Met: A South African eHealth Study

Directory of Open Access Journals (Sweden)

Hendra Van Zyl

2014-03-01

Full Text Available eHealth has been identified as a useful approach to disseminate HIV/AIDS information. Together with Consumer Health Informatics (CHI, the Web-to-Public Knowledge Transfer Model (WPKTM has been applied as a theoretical framework to identify consumer needs for AfroAIDSinfo, a South African Web portal. As part of the CHI practice, regular eSurveys are conducted to determine whether these needs are changing and are continually being met. eSurveys show high rates of satisfaction with the content as well as the modes of delivery. The nature of information is thought of as reliable to reuse; both for education and for referencing of information. Using CHI and the WPKTM as a theoretical framework, it ensures that needs of consumers are being met and that they find the tailored methods of presenting the information agreeable. Combining ICTs and theories in eHealth interventions, this approach can be expanded to deliver information in other sectors of public health.

What Klein’s semantic gradient does and does not really show: decomposing Stroop interference into task and informational conflict components

Directory of Open Access Journals (Sweden)

Yulia eLevin

2016-02-01

Full Text Available The present study suggests that the idea that Stroop interference originates from multiple components may gain theoretically from integrating two independent frameworks. The first framework is represented by the well-known notion of semantic gradient of interference and the second one is the distinction between two types of conflict – the task and the informational conflict – giving rise to the interference (Goldfarb & Henik, 2007; McLeod & MacDonald, 2000. The proposed integration led to the conclusion that two (i.e., orthographic and lexical components of the four theoretically distinct components represent task conflict, and the other two (i.e., indirect and direct informational conflict components represent informational conflict. The four components were independently estimated in a series of experiments. The results confirmed the contribution of task conflict (estimated by a robust orthographic component and of informational conflict (estimated by a strong direct informational conflict component to Stroop interference. However, the performed critical review of the relevant literature (see General Discussion, as well as the results of the experiments reported, showed that the other two components expressing each type of conflict (i.e., the lexical component of task conflict and the indirect informational conflict were small, and unstable. The present analysis refines our knowledge of the origins of Stroop interference by providing evidence that each type of conflict has its major and minor contributions. The implications for cognitive control of an automatic reading process are also discussed.

Micro-Structural Evolution and Size-Effects in Plastically Deformed Single Crystals: Strain Gradient Continuum Modeling

DEFF Research Database (Denmark)

El-Naaman, Salim Abdallah

the macroscopic effects related to strain gradients, most predict smooth micro-structures. The evolution of dislocation micro-structures, during plastic straining of ductile crystalline materials, is highly complex and nonuniform. Published experimental measurements on deformed metal crystals show distinct......An extensive amount of research has been devoted to the development of micro-mechanics based gradient plasticity continuum theories, which are necessary for modeling micron-scale plasticity when large spatial gradients of plastic strain appear. While many models have proven successful in capturing...... strain. It is clear that many challenges are associated with modeling dislocation structures, within a framework based on continuum fields, however, since the strain gradient effects are attributed to the dislocation micro-structure, it is a natural step, in the further development of gradient theories...

Towards a theoretical framework for analyzing complex linguistic networks

CERN Document Server

Lücking, Andy; Banisch, Sven; Blanchard, Philippe; Job, Barbara

2016-01-01

The aim of this book is to advocate and promote network models of linguistic systems that are both based on thorough mathematical models and substantiated in terms of linguistics. In this way, the book contributes first steps towards establishing a statistical network theory as a theoretical basis of linguistic network analysis the boarder of the natural sciences and the humanities.This book addresses researchers who want to get familiar with theoretical developments, computational models and their empirical evaluation in the field of complex linguistic networks. It is intended to all those who are interested in statisticalmodels of linguistic systems from the point of view of network research. This includes all relevant areas of linguistics ranging from phonological, morphological and lexical networks on the one hand and syntactic, semantic and pragmatic networks on the other. In this sense, the volume concerns readers from many disciplines such as physics, linguistics, computer science and information scien...

Can the theoretical domains framework account for the implementation of clinical quality interventions?

Science.gov (United States)

Lipworth, Wendy; Taylor, Natalie; Braithwaite, Jeffrey

2013-12-21

The health care quality improvement movement is a complex enterprise. Implementing clinical quality initiatives requires attitude and behaviour change on the part of clinicians, but this has proven to be difficult. In an attempt to solve this kind of behavioural challenge, the theoretical domains framework (TDF) has been developed. The TDF consists of 14 domains from psychological and organisational theory said to influence behaviour change. No systematic research has been conducted into the ways in which clinical quality initiatives map on to the domains of the framework. We therefore conducted a qualitative mapping experiment to determine to what extent, and in what ways, the TDF is relevant to the implementation of clinical quality interventions. We conducted a thematic synthesis of the qualitative literature exploring clinicians' perceptions of various clinical quality interventions. We analysed and synthesised 50 studies in total, in five domains of clinical quality interventions: clinical quality interventions in general, structural interventions, audit-type interventions, interventions aimed at making practice more evidence-based, and risk management interventions. Data were analysed thematically, followed by synthesis of these themes into categories and concepts, which were then mapped to the domains of the TDF. Our results suggest that the TDF is highly relevant to the implementation of clinical quality interventions. It can be used to map most, if not all, of the attitudinal and behavioural barriers and facilitators of uptake of clinical quality interventions. Each of these 14 domains appeared to be relevant to many different types of clinical quality interventions. One possible additional domain might relate to perceived trustworthiness of those instituting clinical quality interventions. The TDF can be usefully applied to a wide range of clinical quality interventions. Because all 14 of the domains emerged as relevant, and we did not identify any

E-loyalty towards a cancer information website: applying a theoretical framework.

Science.gov (United States)

Crutzen, Rik; Beekers, Nienke; van Eenbergen, Mies; Becker, Monique; Jongen, Lilian; van Osch, Liesbeth

2014-06-01

To provide more insight into user perceptions related to e-loyalty towards a cancer information website. This is needed to assure adequate provision of high quality information during the full process of cancer treatment-from diagnosis to after care-and an important first step towards optimizing cancer information websites in order to promote e-loyalty. Participants were cancer patients (n = 63) and informal caregivers (n = 202) that visited a website providing regional information about cancer care for all types of cancer. Subsequently, they filled out a questionnaire assessing e-loyalty towards the website and user perceptions (efficiency, effectiveness, active trust and enjoyment) based on a theoretical framework derived from the field of e-commerce. A structural equation model was constructed to test the relationships between user perceptions and e-loyalty. Participants in general could find the information they were looking for (efficiency), thought it was relevant (effectiveness) and that they could act upon it (active trust) and thought the visit itself was pleasant (enjoyment). Effectiveness and enjoyment were both positively related with e-loyalty, but this was mediated by active trust. Efficiency was positively related with e-loyalty. The explained variance of e-loyalty was high (R(2)  = 0.70). This study demonstrates that the importance of user perceptions is not limited to fields such as e-commerce but is also present within the context of cancer information websites. The high information need among participants might explain the positive relationship between efficiency and e-loyalty. Therefore, cancer information websites need to foster easy search and access of information provided. Copyright © 2014 John Wiley & Sons, Ltd.

A Game Theoretic Framework for Incentive-Based Models of Intrinsic Motivation in Artificial Systems

Directory of Open Access Journals (Sweden)

Kathryn Elizabeth Merrick

2013-10-01

Full Text Available An emerging body of research is focusing on understanding and building artificial systems that can achieve open-ended development influenced by intrinsic motivations. In particular, research in robotics and machine learning is yielding systems and algorithms with increasing capacity for self-directed learning and autonomy. Traditional software architectures and algorithms are being augmented with intrinsic motivations to drive cumulative acquisition of knowledge and skills. Intrinsic motivations have recently been considered in reinforcement learning, active learning and supervised learning settings among others. This paper considers game theory as a novel setting for intrinsic motivation. A game theoretic framework for intrinsic motivation is formulated by introducing the concept of optimally motivating incentive as a lens through which players perceive a game. Transformations of four well-known mixed-motive games are presented to demonstrate the perceived games when players’ optimally motivating incentive falls in three cases corresponding to strong power, affiliation and achievement motivation. We use agent-based simulations to demonstrate that players with different optimally motivating incentive act differently as a result of their altered perception of the game. We discuss the implications of these results both for modeling human behavior and for designing artificial agents or robots.

A game theoretic framework for incentive-based models of intrinsic motivation in artificial systems.

Science.gov (United States)

Merrick, Kathryn E; Shafi, Kamran

2013-01-01

An emerging body of research is focusing on understanding and building artificial systems that can achieve open-ended development influenced by intrinsic motivations. In particular, research in robotics and machine learning is yielding systems and algorithms with increasing capacity for self-directed learning and autonomy. Traditional software architectures and algorithms are being augmented with intrinsic motivations to drive cumulative acquisition of knowledge and skills. Intrinsic motivations have recently been considered in reinforcement learning, active learning and supervised learning settings among others. This paper considers game theory as a novel setting for intrinsic motivation. A game theoretic framework for intrinsic motivation is formulated by introducing the concept of optimally motivating incentive as a lens through which players perceive a game. Transformations of four well-known mixed-motive games are presented to demonstrate the perceived games when players' optimally motivating incentive falls in three cases corresponding to strong power, affiliation and achievement motivation. We use agent-based simulations to demonstrate that players with different optimally motivating incentive act differently as a result of their altered perception of the game. We discuss the implications of these results both for modeling human behavior and for designing artificial agents or robots.

Optimization in Quaternion Dynamic Systems: Gradient, Hessian, and Learning Algorithms.

Science.gov (United States)

Xu, Dongpo; Xia, Yili; Mandic, Danilo P

2016-02-01

The optimization of real scalar functions of quaternion variables, such as the mean square error or array output power, underpins many practical applications. Solutions typically require the calculation of the gradient and Hessian. However, real functions of quaternion variables are essentially nonanalytic, which are prohibitive to the development of quaternion-valued learning systems. To address this issue, we propose new definitions of quaternion gradient and Hessian, based on the novel generalized Hamilton-real (GHR) calculus, thus making a possible efficient derivation of general optimization algorithms directly in the quaternion field, rather than using the isomorphism with the real domain, as is current practice. In addition, unlike the existing quaternion gradients, the GHR calculus allows for the product and chain rule, and for a one-to-one correspondence of the novel quaternion gradient and Hessian with their real counterparts. Properties of the quaternion gradient and Hessian relevant to numerical applications are also introduced, opening a new avenue of research in quaternion optimization and greatly simplified the derivations of learning algorithms. The proposed GHR calculus is shown to yield the same generic algorithm forms as the corresponding real- and complex-valued algorithms. Advantages of the proposed framework are illuminated over illustrative simulations in quaternion signal processing and neural networks.

Mobile user experience for voice services: A theoretical framework

CSIR Research Space (South Africa)

Botha, Adèle

2012-02-01

Full Text Available The purpose of this paper is to provide a “Mobile User Experience Framework for Voice services.” The rapid spread of mobile cellular technology within Africa has made it a prime vehicle for accessing services and content. The challenge remains...

Quality correction factors of composite IMRT beam deliveries: Theoretical considerations

International Nuclear Information System (INIS)

Bouchard, Hugo

2012-01-01

Purpose: In the scope of intensity modulated radiation therapy (IMRT) dosimetry using ionization chambers, quality correction factors of plan-class-specific reference (PCSR) fields are theoretically investigated. The symmetry of the problem is studied to provide recommendable criteria for composite beam deliveries where correction factors are minimal and also to establish a theoretical limit for PCSR delivery k Q factors. Methods: The concept of virtual symmetric collapsed (VSC) beam, being associated to a given modulated composite delivery, is defined in the scope of this investigation. Under symmetrical measurement conditions, any composite delivery has the property of having a k Q factor identical to its associated VSC beam. Using this concept of VSC, a fundamental property of IMRT k Q factors is demonstrated in the form of a theorem. The sensitivity to the conditions required by the theorem is thoroughly examined. Results: The theorem states that if a composite modulated beam delivery produces a uniform dose distribution in a volume V cyl which is symmetric with the cylindrical delivery and all beams fulfills two conditions in V cyl : (1) the dose modulation function is unchanged along the beam axis, and (2) the dose gradient in the beam direction is constant for a given lateral position; then its associated VSC beam produces no lateral dose gradient in V cyl , no matter what beam modulation or gantry angles are being used. The examination of the conditions required by the theorem lead to the following results. The effect of the depth-dose gradient not being perfectly constant with depth on the VSC beam lateral dose gradient is found negligible. The effect of the dose modulation function being degraded with depth on the VSC beam lateral dose gradient is found to be only related to scatter and beam hardening, as the theorem holds also for diverging beams. Conclusions: The use of the symmetry of the problem in the present paper leads to a valuable theorem showing

Development of a theoretical framework of factors affecting patient safety incident reporting: a theoretical review of the literature

Science.gov (United States)

Hull, Louise; Soukup, Tayana; Mayer, Erik; Athanasiou, Thanos; Sevdalis, Nick; Darzi, Ara

2017-01-01

Objectives The development and implementation of incident reporting systems within healthcare continues to be a fundamental strategy to reduce preventable patient harm and improve the quality and safety of healthcare. We sought to identify factors contributing to patient safety incident reporting. Design To facilitate improvements in incident reporting, a theoretical framework, encompassing factors that act as barriers and enablers ofreporting, was developed. Embase, Ovid MEDLINE(R) and PsycINFO were searched to identify relevant articles published between January 1980 and May 2014. A comprehensive search strategy including MeSH terms and keywords was developed to identify relevant articles. Data were extracted by three independent researchers; to ensure the accuracy of data extraction, all studies eligible for inclusion were rescreened by two reviewers. Results The literature search identified 3049 potentially eligible articles; of these, 110 articles, including >29 726 participants, met the inclusion criteria. In total, 748 barriers were identified (frequency count) across the 110 articles. In comparison, 372 facilitators to incident reporting and 118 negative cases were identified. The top two barriers cited were fear of adverse consequences (161, representing 21.52% of barriers) and process and systems of reporting (110, representing 14.71% of barriers). In comparison, the top two facilitators were organisational (97, representing 26.08% of facilitators) and process and systems of reporting (75, representing 20.16% of facilitators). Conclusion A wide range of factors contributing to engagement in incident reporting exist. Efforts that address the current tendency to under-report must consider the full range of factors in order to develop interventions as well as a strategic policy approach for improvement. PMID:29284714

Theoretical frameworks for testing relativistic gravity: A review

Science.gov (United States)

Thorne, K. S.; Will, C. M.; Ni, W.

1971-01-01

Metric theories of gravity are presented, including the definition of metric theory, evidence for its existence, and response of matter to gravity with test body trajectories, gravitational red shift, and stressed matter responses. Parametrized post-Newtonian framework and interpretations are reviewed. Gamma, beta and gamma, and varied other parameters were measured. Deflection of electromagnetic waves, radar time delay, geodetic gyroscope precession, perihelion shifts, and periodic effects in orbits are among various studies carried out for metric theory experimentation.

A THEORETICAL FRAMEWORK FOR COMBINING TECHNIQUES THAT PROBE THE LINK BETWEEN GALAXIES AND DARK MATTER

International Nuclear Information System (INIS)

Leauthaud, Alexie; Tinker, Jeremy; Behroozi, Peter S.; Busha, Michael T.; Wechsler, Risa H.

2011-01-01

We develop a theoretical framework that combines measurements of galaxy-galaxy lensing, galaxy clustering, and the galaxy stellar mass function in a self-consistent manner. While considerable effort has been invested in exploring each of these probes individually, attempts to combine them are still in their infancy. These combinations have the potential to elucidate the galaxy-dark matter connection and the galaxy formation physics responsible for it, as well as to constrain cosmological parameters and to test the nature of gravity. In this paper, we focus on a theoretical model that describes the galaxy-dark matter connection based on standard halo occupation distribution techniques. Several key modifications enable us to extract additional parameters that determine the stellar-to-halo mass relation and to simultaneously fit data from multiple probes while allowing for independent binning schemes for each probe. We construct mock catalogs from numerical simulations to investigate the effects of sample variance and covariance for each probe. Finally, we analyze how trends in each of the three observables impact the derived parameters of the model. In particular, we investigate various features of the observed galaxy stellar mass function (low-mass slope, 'plateau', knee, and high-mass cutoff) and show how each feature is related to the underlying relationship between stellar and halo mass. We demonstrate that the observed 'plateau' feature in the stellar mass function at M * ∼ 2 x 10 10 M sun is due to the transition that occurs in the stellar-to-halo mass relation at M h ∼ 10 12 M sun from a low-mass power-law regime to a sub-exponential function at higher stellar mass.

Enviromental Effects on Internal Color Gradients of Early-Type Galaxies

Science.gov (United States)

La Barbera, F.; de Carvalho, R. R.; Gal, R. R.; Busarello, G.; Haines, C. P.; Mercurio, A.; Merluzzi, P.; Capaccioli, M.; Djorgovski, S. G.

2007-05-01

One of the most debated issues of observational and theoretical cosmology is that of how the environment affects the formation and evolution of galaxies. To gain new insight into this subject, we have derived surface photometry for a sample of 3,000 early-type galaxies belonging to 163 clusters with different richness, spanning a redshift range of 0.05 to 0.25. This large data-set is used to analyze how the color distribution inside galaxies depends on several parameters, such as cluster richness, local galaxy density, galaxy luminosity and redshift. We find that the internal color profile of galaxies strongly depends on the environment where galaxies reside. Galaxies in poor and rich clusters are found to follow two distinct trends in the color gradient vs. redshift diagram, with color gradients beeing less steep in rich rather than in poor clusters. No dependence of color gradients on galaxy luminosity is detected both for poor and rich clusters. We find that color gradients strongly depend on local galaxy density, with more shallow gradients in high density regions. Interestingly, this result holds only for low richness clusters, with color gradients of galaxies in rich clusters showing no dependence on local galaxy density. Our results support a reasonable picture whereby young early-type galaxies form in a dissipative collapse process, and then undergo increased (either major or minor) merging activity in richer rather than in poor clusters.

The Complex Gradient Operator and the CR-Calculus

OpenAIRE

Kreutz-Delgado, Ken

2009-01-01

A thorough discussion and development of the calculus of real-valued functions of complex-valued vectors is given using the framework of the Wirtinger Calculus. The presented material is suitable for exposition in an introductory Electrical Engineering graduate level course on the use of complex gradients and complex Hessian matrices, and has been successfully used in teaching at UC San Diego. Going beyond the commonly encountered treatments of the first-order complex vector calculus, second-...

Cultural Psychology of Differences and EMS; a New Theoretical Framework for Understanding and Reconstructing Culture.

Science.gov (United States)

Yamamoto, Toshiya

2017-09-01

In this paper I introduce the outlines of our new type of theoretical framework named 'Cultural psychology of Differences' for understanding cultural others and dialogically reconstructing interactions among cultural others. In order to understand cultural others, it is necessary for us to reconstruct a new concept which enables us to analyze dynamic generation processes of culture. We propose the concept of Expanded Mediational Structure, EMS, as an elementary unit for understanding human social interactions. EMS is composed of subjects who interacts each other using objects of some kind as mediators, and a normative mediator, NM, which mediates their interactions. It is necessary to generate, share and adjust a NM to keep social interactions stable, and culture will appear when interaction malfunction is attributed to a gaps of NMs. The concept of EMS helps us to understand how culture is functionally substantialized in the plane of collective (or communal) intersubjectivity and how cultural conflicts develop and intensify. Focusing on the generation process of culture through interactions provides us with another option to understand cultural others through dialogical interactions with them.

Exploring behavioural determinants relating to health professional reporting of medication errors: a qualitative study using the Theoretical Domains Framework.

Science.gov (United States)

Alqubaisi, Mai; Tonna, Antonella; Strath, Alison; Stewart, Derek

2016-07-01

Effective and efficient medication reporting processes are essential in promoting patient safety. Few qualitative studies have explored reporting of medication errors by health professionals, and none have made reference to behavioural theories. The objective was to describe and understand the behavioural determinants of health professional reporting of medication errors in the United Arab Emirates (UAE). This was a qualitative study comprising face-to-face, semi-structured interviews within three major medical/surgical hospitals of Abu Dhabi, the UAE. Health professionals were sampled purposively in strata of profession and years of experience. The semi-structured interview schedule focused on behavioural determinants around medication error reporting, facilitators, barriers and experiences. The Theoretical Domains Framework (TDF; a framework of theories of behaviour change) was used as a coding framework. Ethical approval was obtained from a UK university and all participating hospital ethics committees. Data saturation was achieved after interviewing ten nurses, ten pharmacists and nine physicians. Whilst it appeared that patient safety and organisational improvement goals and intentions were behavioural determinants which facilitated reporting, there were key determinants which deterred reporting. These included the beliefs of the consequences of reporting (lack of any feedback following reporting and impacting professional reputation, relationships and career progression), emotions (fear and worry) and issues related to the environmental context (time taken to report). These key behavioural determinants which negatively impact error reporting can facilitate the development of an intervention, centring on organisational safety and reporting culture, to enhance reporting effectiveness and efficiency.

Research in theoretical nuclear physics

International Nuclear Information System (INIS)

Udagawa, T.

1993-11-01

This report describes the accomplishments in basic research in nuclear physics carried out by the theoretical nuclear physics group in the Department of Physics at the University of Texas at Austin, during the period of November 1, 1992 to October 31, 1993. The work done covers three separate areas, low-energy nuclear reactions, intermediate energy physics, and nuclear structure studies. Although the subjects are thus spread among different areas, they are based on two techniques developed in previous years. These techniques are a powerful method for continuum-random-phase-approximation (CRPA) calculations of nuclear response and the breakup-fusion (BF) approach to incomplete fusion reactions, which calculation on a single footing of various incomplete fusion reaction cross sections within the framework of direct reaction theories. The approach was developed as a part of a more general program for establishing an approach to describing all different types of nuclear reactions, i.e., complete fusion, incomplete fusion and direct reactions, in a systematic way based on single theoretical framework

Hardening and strengthening behavior in rate-independent strain gradient crystal plasticity

DEFF Research Database (Denmark)

Nellemann, C.; Niordson, C. F.; Nielsen, K.L.

2018-01-01

Two rate-independent strain gradient crystal plasticity models, one new and one previously published, are compared and a numerical framework that encompasses both is developed. The model previously published is briefly outlined, while an in-depth description is given for the new, yet somewhat...... related,model. The difference between the two models is found in the definitions of the plastic work expended in the material and their relation to spatial gradients of plastic strains. The model predictions are highly relevant to the ongoing discussion in the literature, concerning 1) what governs...... the increase in the apparent yield stress due to strain gradients (also referred to as strengthening)? And 2), what is the implication of such strengthening in relation to crystalline material behavior at the micron scale? The present work characterizes material behavior, and the corresponding plastic slip...

Theoretical analysis of balanced truncation for linear switched systems

DEFF Research Database (Denmark)

Petreczky, Mihaly; Wisniewski, Rafal; Leth, John-Josef

2012-01-01

In this paper we present theoretical analysis of model reduction of linear switched systems based on balanced truncation, presented in [1,2]. More precisely, (1) we provide a bound on the estimation error using L2 gain, (2) we provide a system theoretic interpretation of grammians and their singu......In this paper we present theoretical analysis of model reduction of linear switched systems based on balanced truncation, presented in [1,2]. More precisely, (1) we provide a bound on the estimation error using L2 gain, (2) we provide a system theoretic interpretation of grammians...... for showing this independence is realization theory of linear switched systems. [1] H. R. Shaker and R. Wisniewski, "Generalized gramian framework for model/controller order reduction of switched systems", International Journal of Systems Science, Vol. 42, Issue 8, 2011, 1277-1291. [2] H. R. Shaker and R....... Wisniewski, "Switched Systems Reduction Framework Based on Convex Combination of Generalized Gramians", Journal of Control Science and Engineering, 2009....

A guide to using the Theoretical Domains Framework of behaviour change to investigate implementation problems.

Science.gov (United States)

Atkins, Lou; Francis, Jill; Islam, Rafat; O'Connor, Denise; Patey, Andrea; Ivers, Noah; Foy, Robbie; Duncan, Eilidh M; Colquhoun, Heather; Grimshaw, Jeremy M; Lawton, Rebecca; Michie, Susan

2017-06-21

Implementing new practices requires changes in the behaviour of relevant actors, and this is facilitated by understanding of the determinants of current and desired behaviours. The Theoretical Domains Framework (TDF) was developed by a collaboration of behavioural scientists and implementation researchers who identified theories relevant to implementation and grouped constructs from these theories into domains. The collaboration aimed to provide a comprehensive, theory-informed approach to identify determinants of behaviour. The first version was published in 2005, and a subsequent version following a validation exercise was published in 2012. This guide offers practical guidance for those who wish to apply the TDF to assess implementation problems and support intervention design. It presents a brief rationale for using a theoretical approach to investigate and address implementation problems, summarises the TDF and its development, and describes how to apply the TDF to achieve implementation objectives. Examples from the implementation research literature are presented to illustrate relevant methods and practical considerations. Researchers from Canada, the UK and Australia attended a 3-day meeting in December 2012 to build an international collaboration among researchers and decision-makers interested in the advancing use of the TDF. The participants were experienced in using the TDF to assess implementation problems, design interventions, and/or understand change processes. This guide is an output of the meeting and also draws on the authors' collective experience. Examples from the implementation research literature judged by authors to be representative of specific applications of the TDF are included in this guide. We explain and illustrate methods, with a focus on qualitative approaches, for selecting and specifying target behaviours key to implementation, selecting the study design, deciding the sampling strategy, developing study materials, collecting and

Boundedness and convergence of online gradient method with penalty for feedforward neural networks.

Science.gov (United States)

Zhang, Huisheng; Wu, Wei; Liu, Fei; Yao, Mingchen

2009-06-01

In this brief, we consider an online gradient method with penalty for training feedforward neural networks. Specifically, the penalty is a term proportional to the norm of the weights. Its roles in the method are to control the magnitude of the weights and to improve the generalization performance of the network. By proving that the weights are automatically bounded in the network training with penalty, we simplify the conditions that are required for convergence of online gradient method in literature. A numerical example is given to support the theoretical analysis.

[Relational frame theory - a theoretical framework for contextual behavioral science].

Science.gov (United States)

Kensche, M; Schweiger, U

2015-05-01

Therapists have to deal with verbal systems and often work with verbal exchange. Therefore, a psychological theory is required, which teaches the therapist how to accomplish this task. The BRT is a theory of human language and cognition that explains how people use their verbal behavior as stimuli in their interrelations and how they act and react, based on the resulting relationships. This behavior is learned very early in the course of language acquisition and functions as a generalized operant. A prerequisite for this is the ability of people to undergo mental simulation. This enables them to construct diverse relational frameworks between individual stimuli. Without relational frameworks, people cannot function. The ability to establish a relational framework is a prerequisite for the formation of rule-governed behavior. Rule-governed behavior economizes complex decision processes, creates interpersonal security and enables dealing with events before they take place. On the other hand, the same properties that enable people to solve problems effectively can also contribute to rigid adherence to rules and experience avoidance. Relational frameworks, once established, outweigh other sources of behavioral regulation. Thus, it can become the basis of psychopathology. Poor contextual control makes it difficult for people to devote flexible, focused and voluntary attention to the present and align their actions with the immediate present. Contextual psychotherapy methods that are based on the BRT start precisely at this point: Targeted establishment of new contingencies in the therapeutic interaction through systematic strengthening of metacognitive mode and through the establishment of new rules that make possible a change in the rule-governed behavior enable undermining of dysfunctional rule-governed behavior and build up desirable behavior. This allows any therapeutic process to be more effective - regardless of the patient's expressed symptoms. © Georg Thieme

[Relational Frame Theory--A Theoretical Framework for Contextual Behavioral Science].

Science.gov (United States)

Kensche, M; Schweiger, U

2015-07-01

Therapists have to deal with verbal systems and often work with verbal exchange. Therefore, a psychological theory is required, which teaches the therapist how to accomplish this task. The BRT is a theory of human language and cognition that explains how people use their verbal behavior as stimuli in their interrelations and how they act and react, based on the resulting relationships. This behavior is learned very early in the course of language acquisition and functions as a generalized operant. A prerequisite for this is the ability of people to undergo mental simulation. This enables them to construct diverse relational frameworks between individual stimuli. Without relational frameworks, people cannot function. The ability to establish a relational framework is a prerequisite for the formation of rule-governed behavior. Rule-governed behavior economizes complex decision processes, creates interpersonal security and enables dealing with events before they take place. On the other hand, the same properties that enable people to solve problems effectively can also contribute to rigid adherence to rules and experience avoidance. Relational frameworks, once established, outweigh other sources of behavioral regulation. Thus, it can become the basis of psychopathology. Poor contextual control makes it difficult for people to devote flexible, focused and voluntary attention to the present and align their actions with the immediate present. Contextual psychotherapy methods that are based on the BRT start precisely at this point: Targeted establishment of new contingencies in the therapeutic interaction through systematic strengthening of metacognitive mode and through the establishment of new rules that make possible a change in the rule-governed behavior enable undermining of dysfunctional rule-governed behavior and build up desirable behavior. This allows any therapeutic process to be more effective--regardless of the patient's expressed symptoms. © Georg Thieme

The Development Of A Theoretical Lean Culture Causal Framework To Support The Effective Implementation Of Lean In Automotive Component Manufacturers

Directory of Open Access Journals (Sweden)

Van der Merwe, Karl Robert

2014-05-01

Full Text Available Although it is generally accepted that lean manufacturing improves operational performance, many organisations are struggling to adapt to the lean philosophy. The purpose of this study is to contribute to a more effective strategy for implementing the lean manufacturing improvement philosophy. The study sets out both to integrate well-researched findings and theories related to generic organisational culture with more recent research and experience related to lean culture, and to examine the role that culture plays in the effective implementation of lean manufacturing principles and techniques. The ultimate aim of this exercise is to develop a theoretical lean culture causal framework.

New applications of a generalized Hooke’s law for second gradient materials

Directory of Open Access Journals (Sweden)

K. Enakoutsa

2015-05-01

Full Text Available We provide analytical solutions to the problems of a circular bending of a beam in plane strain and the torsion of a non-circular cross-section beam, the beams obeying a second-gradient elasticity law proposed by the author, following a previous suggestion of Dell’Isola et al. (2009. The motivation was to find benchmark analytical solutions that can serve to grasp the physical foundations of second gradient elasticity laws for heterogeneous materials. The analytical solution of the circular beam problem presents the additional advantage to establish some nice properties on the unknown second gradient elastic moduli introduced by Enakoutsa (2014 model and the classical elasticity constants for both incompressible and compressible heterogeneous elastic materials. A framework to find the elastic moduli of the new model is also proposed.

The influence of ALN-Al gradient material gradient index on ballistic performance

International Nuclear Information System (INIS)

Wang Youcong; Liu Qiwen; Li Yao; Shen Qiang

2013-01-01

Ballistic performance of the gradient material is superior to laminated material, and gradient materials have different gradient types. Using ls-dyna to simulate the ballistic performance of ALN-AL gradient target plates which contain three gradient index (b = 1, b = 0.5, b = 2). Through Hopkinson bar numerical simulation to the target plate materials, we obtained the reflection stress wave and transmission stress wave state of gradient material to get the best gradient index. The internal stress state of gradient material is simulated by amplification processing of the target plate model. When the gradient index b is equal to 1, the gradient target plate is best of all.

Synthesis, structural characterization, luminescent properties and theoretical study of three novel lanthanide metal-organic frameworks of Ho(III), Gd(III) and Eu(III) with 2,5-thiophenedicarboxylate anion

Energy Technology Data Exchange (ETDEWEB)

Marques, Lippy F. [Instituto de Química, Universidade do Estado do Rio de Janeiro, Rio de Janeiro 20550-013 (Brazil); Correa, Charlane C. [Departamento de Química-ICE, Universidade Federal de Juiz de Fora, Juiz de Fora-MG, 36036-330 (Brazil); Ribeiro, Sidney J.L.; Santos, Molíria V. dos [Institute of Chemistry, São Paulo State University − UNESP, CP 355 Araraquara-SP 14801-970 Brazil (Brazil); Dutra, José Diogo L.; Freire, Ricardo O. [Pople Computational Chemistry Laboratory, Departamento de Química, Universidade Federal de Sergipe, São Cristóvão-SE 49100-000 (Brazil); Machado, Flávia C., E-mail: flavia.machado@ufjf.edu.br [Departamento de Química-ICE, Universidade Federal de Juiz de Fora, Juiz de Fora-MG, 36036-330 (Brazil)

2015-07-15

In this paper, the synthesis of three new metal-organic frameworks of lanthanides (LnMOFs) ([Ln{sub 2}(2,5-tdc){sub 3}(dmso){sub 2}]·H{sub 2}O){sub n} (Ln=Ho (1); Gd (2); Eu (3); 2,5-tdc=2,5-thiophenedicarboxylate anion; dmso=dimethylsulfoxide), and their complete characterization, including single crystal X-ray diffraction, FTIR spectroscopy and thermogravimetric analysis are reported. In especial, photophysical properties of Eu(III) complex have been studied in detail via both theoretical and experimental approaches. Crystal structure of (1) reveals that each lanthanide ion is seven-coordinated by oxygen atoms in an overall distorted capped trigonal – prismatic geometry. The 2,5-tdc{sup 2−} ligands connect four Ln(III) centers, adopting (κ{sup 1}–κ{sup 1})–(κ{sup 1}–κ{sup 1})–μ{sub 4} coordination mode, generating an 8-connected uninodal 3D network. In addition, theoretical studies for Eu(III) complex were performed using the Sparkle model for lanthanide complexes. - Graphical abstract: Three new metal-organic frameworks of lanthanides (LnMOFs) ([Ln{sub 2}(2,5-tdc){sub 3}(dmso){sub 2}]·H{sub 2}O){sub n} (Ln=Ho (1); Gd (2); Eu (3); 2,5-tdc=2,5-thiophenedicarboxylate anion; dmso=dimethylsulfoxide), were synthesized and their complete characterization, including single crystal X-ray diffraction, FTIR spectroscopy and thermogravimetric analysis are reported. In especial, photophysical properties of Eu(III) complex have been studied in detail via both theoretical and experimental approaches. - Highlights: • Three new LnMOFs were synthesized and fully characterized. • Ho{sup 3+}, Gd{sup 3+} and Eu{sup 3+} complexes photoluminescence properties were investigated. • Theoretical approaches for Eu{sup 3+} complex luminescence has been performed. • An energy level diagram is used to establish the ligand-to-metal energy transfer. • These metal−organic frameworks can act as light conversion molecular devices.

Choosing Appropriate Theories for Understanding Hospital Reporting of Adverse Drug Events, a Theoretical Domains Framework Approach.

Science.gov (United States)

Shalviri, Gloria; Yazdizadeh, Bahareh; Mirbaha, Fariba; Gholami, Kheirollah; Majdzadeh, Reza

2018-01-01

Adverse drug events (ADEs) may cause serious injuries including death. Spontaneous reporting of ADEs plays a great role in detection and prevention of them; however, underreporting always exists. Although several interventions have been utilized to solve this problem, they are mainly based on experience and the rationale for choosing them has no theoretical base. The vast variety of behavioural theories makes it difficult to choose appropriate theory. Theoretical domains framework (TDF) is suggested as a solution. The objective of this study was to select the best theory for evaluating ADE reporting in hospitals based on TDF. We carried out three focus group discussions with hospital pharmacists and nurses, based on TDF questions. The analysis was performed through five steps including coding discussions transcript, extracting beliefs, selecting relevant domains, matching related constructs to the extracted beliefs, and determining the appropriate theories in each domain. The theory with the highest number of matched domains and constructs was selected as the theory of choice. A total of six domains were identified relevant to ADE reporting, including "Knowledge", "Skills", "Beliefs about consequences", "Motivation and goals", "Environmental context and resources" and "Social influences". We found theory of planned behavior as the comprehensive theory to study factors influencing ADE reporting in hospitals, since it was relevant theory in five out of six relevant domains and the common theory in 55 out of 75 identified beliefs. In conclusion, we suggest theory of planned behavior for further studies on designing appropriate interventions to increase ADE reporting in hospitals.

3D correlation imaging of the vertical gradient of gravity data

International Nuclear Information System (INIS)

Guo, Lianghui; Meng, Xiaohong; Shi, Lei

2011-01-01

We present a new 3D correlation imaging approach for vertical gradient of gravity data for deriving a 3D equivalent mass distribution in the subsurface. In this approach, we divide the subsurface space into a 3D regular grid, and then at each grid node calculate a cross correlation between the vertical gradient of the observed gravity data and the theoretical gravity vertical gradient due to a point mass source. The resultant correlation coefficients are used to describe the equivalent mass distribution in a probability sense. We simulate a geological syncline model intruded by a dike and later broken by two vertical faults. The vertical gradient of gravity anomaly of the model is calculated and used to test the approach. The results demonstrate that the equivalent mass distribution derived by the approach reflects the basic geological structures of the model. We also test the approach on the transformed vertical gradient of real Bouguer gravity data from a geothermal survey area in Northern China. The thermal reservoirs are located in the lower portion of the sedimentary basin. From the resultant equivalent mass distribution, we produce the depth distribution of the bottom interface of the basin and predict possible hidden faults present in the basin

Controlling an acoustic wave with a cylindrically-symmetric gradient-index system

International Nuclear Information System (INIS)

Zhang Zhe; Li Rui-Qi; Liang Bin; Zou Xin-Ye; Cheng Jian-Chun

2015-01-01

We present a detailed theoretical description of wave propagation in an acoustic gradient-index system with cylindrical symmetry and demonstrate its potential to numerically control acoustic waves in different ways. The trajectory of an acoustic wave within the system is derived by employing the theory of geometric acoustics, and the validity of the theoretical descriptions is verified numerically by using the finite element method simulation. The results show that by tailoring the distribution function of the refractive index, the proposed system can yield a tunable manipulation of acoustic waves, such as acoustic bending, trapping, and absorbing. (paper)

A theoretical framework for whole-plant carbon assimilation efficiency based on metabolic scaling theory: a test case using Picea seedlings.

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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

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

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Almalki, Manal; Gray, Kathleen; Martin-Sanchez, Fernando

2016-05-27

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. 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? 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. 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 constructs of health SQ activity. A

The design and testing of a caring teaching model based on the theoretical framework of caring in the Chinese Context: a mixed-method study.

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Guo, Yujie; Shen, Jie; Ye, Xuchun; Chen, Huali; Jiang, Anli

2013-08-01

This paper aims to report the design and test the effectiveness of an innovative caring teaching model based on the theoretical framework of caring in the Chinese context. Since the 1970's, caring has been a core value in nursing education. In a previous study, a theoretical framework of caring in the Chinese context is explored employing a grounded theory study, considered beneficial for caring education. A caring teaching model was designed theoretically and a one group pre- and post-test quasi-experimental study was administered to test its effectiveness. From Oct, 2009 to Jul, 2010, a cohort of grade-2 undergraduate nursing students (n=64) in a Chinese medical school was recruited to participate in the study. Data were gathered through quantitative and qualitative methods to evaluate the effectiveness of the caring teaching model. The caring teaching model created an esthetic situation and experiential learning style for teaching caring that was integrated within the curricula. Quantitative data from the quasi-experimental study showed that the post-test scores of each item were higher than those on the pre-test (p<0.01). Thematic analysis of 1220 narratives from students' caring journals and reports of participant class observation revealed two main thematic categories, which reflected, from the students' points of view, the development of student caring character and the impact that the caring teaching model had on this regard. The model could be used as an integrated approach to teach caring in nursing curricula. It would also be beneficial for nursing administrators in cultivating caring nurse practitioners. Copyright © 2012 Elsevier Ltd. All rights reserved.

Development of a theoretical framework of factors affecting patient safety incident reporting: a theoretical review of the literature.

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Archer, Stephanie; Hull, Louise; Soukup, Tayana; Mayer, Erik; Athanasiou, Thanos; Sevdalis, Nick; Darzi, Ara

2017-12-27

The development and implementation of incident reporting systems within healthcare continues to be a fundamental strategy to reduce preventable patient harm and improve the quality and safety of healthcare. We sought to identify factors contributing to patient safety incident reporting. To facilitate improvements in incident reporting, a theoretical framework, encompassing factors that act as barriers and enablers ofreporting, was developed. Embase, Ovid MEDLINE(R) and PsycINFO were searched to identify relevant articles published between January 1980 and May 2014. A comprehensive search strategy including MeSH terms and keywords was developed to identify relevant articles. Data were extracted by three independent researchers; to ensure the accuracy of data extraction, all studies eligible for inclusion were rescreened by two reviewers. The literature search identified 3049 potentially eligible articles; of these, 110 articles, including >29 726 participants, met the inclusion criteria. In total, 748 barriers were identified (frequency count) across the 110 articles. In comparison, 372 facilitators to incident reporting and 118 negative cases were identified. The top two barriers cited were fear of adverse consequences (161, representing 21.52% of barriers) and process and systems of reporting (110, representing 14.71% of barriers). In comparison, the top two facilitators were organisational (97, representing 26.08% of facilitators) and process and systems of reporting (75, representing 20.16% of facilitators). A wide range of factors contributing to engagement in incident reporting exist. Efforts that address the current tendency to under-report must consider the full range of factors in order to develop interventions as well as a strategic policy approach for improvement. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

A theoretical framework to describe communication processes during medical disability assessment interviews

Directory of Open Access Journals (Sweden)

Schellart Antonius JM

2009-10-01

Full Text Available Abstract Background Research in different fields of medicine suggests that communication is important in physician-patient encounters and influences satisfaction with these encounters. It is argued that this also applies to the non-curative tasks that physicians perform, such as sickness certification and medical disability assessments. However, there is no conceptualised theoretical framework that can be used to describe intentions with regard to communication behaviour, communication behaviour itself, and satisfaction with communication behaviour in a medical disability assessment context. Objective The objective of this paper is to describe the conceptualisation of a model for the communication behaviour of physicians performing medical disability assessments in a social insurance context and of their claimants, in face-to-face encounters during medical disability assessment interviews and the preparation thereof. Conceptualisation The behavioural model, based on the Theory of Planned Behaviour (TPB, is conceptualised for the communication behaviour of social insurance physicians and claimants separately, but also combined during the assessment interview. Other important concepts in the model are the evaluation of communication behaviour (satisfaction, intentions, attitudes, skills, and barriers for communication. Conclusion The conceptualisation of the TPB-based behavioural model will help to provide insight into the communication behaviour of social insurance physicians and claimants during disability assessment interviews. After empirical testing of the relationships in the model, it can be used in other studies to obtain more insight into communication behaviour in non-curative medicine, and it could help social insurance physicians to adapt their communication behaviour to their task when performing disability assessments.

[Towards a theoretical framework for rethinking cultural accessibility].

Science.gov (United States)

Landini, Fernando; Cowes, Valeria González; D'Amore, Eliana

2014-02-01

Health services accessibility is a key health policy issue. However, few in-depth studies have addressed it theoretically. Most distinguish between availability, accessibility, and acceptability, or between geographic, financial, administrative, and cultural accessibility. We discuss and analyze the concept of accessibility as conflictive articulation between supply and demand in health. The article addresses the importance of cultural accessibility, rethinking it as a social interface, i.e., a social arena with clashing worldviews (namely, those of physicians and patients). The approach sheds light on the complex processes of grasping, translating, and reshaping knowledge and recommendations within such interaction.

Developing a Theoretical Framework Using a Nursing Perspective to Investigate Perceived Health in the "Sandwich Generation" Group.

Science.gov (United States)

Oulevey Bachmann, Annie; Danuser, Brigitta; Morin, Diane

2015-10-01

Coexisting workloads from professional, household and family, and caregiving activities for frail parents expose middle-aged individuals, the so-called "Sandwich Generation", to potential health risks. Current trends suggest that this situation will continue or increase. Thus SG health promotion has become a nursing concern. Most existing research considers coexisting workloads a priori pathogenic. Most studies have examined the association of one, versus two, of these three activities with health. Few studies have used a nursing perspective. This article presents the development of a framework based on a nursing model. We integrated Siegrist's Effort-Reward Imbalance middle-range theory into "Neuman Systems Model". The latter was chosen for its salutogenic orientation, its attention to preventive nursing interventions and the opportunity it provides to simultaneously consider positive and negative perceptions of SG health and SG coexisting workloads. Finally, it facilitated a theoretical identification of health protective factors. © The Author(s) 2015.

Understanding the Canadian adult CT head rule trial: use of the theoretical domains framework for process evaluation

Directory of Open Access Journals (Sweden)

Curran Janet A

2013-02-01

Full Text Available Abstract Background The Canadian CT Head Rule was prospectively derived and validated to assist clinicians with diagnostic decision-making regarding the use of computed tomography (CT in adult patients with minor head injury. A recent intervention trial failed to demonstrate a decrease in the rate of head CTs following implementation of the rule in Canadian emergency departments. Yet, the same intervention, which included a one-hour educational session and reminders at the point of requisition, was successful in reducing cervical spine imaging rates in the same emergency departments. The reason for the varied effect of the intervention across these two behaviours is unclear. There is an increasing appreciation for the use of theory to conduct process evaluations to better understand how strategies are linked with outcomes in implementation trials. The Theoretical Domains Framework (TDF has been used to explore health professional behaviour and to design behaviour change interventions but, to date, has not been used to guide a theory-based process evaluation. In this proof of concept study, we explored whether the TDF could be used to guide a retrospective process evaluation to better understand emergency physicians’ responses to the interventions employed in the Canadian CT Head Rule trial. Methods A semi-structured interview guide, based on the 12 domains from the TDF, was used to conduct telephone interviews with project leads and physician participants from the intervention sites in the Canadian CT Head Rule trial. Two reviewers independently coded the anonymised interview transcripts using the TDF as a coding framework. Relevant domains were identified by: the presence of conflicting beliefs within a domain; the frequency of beliefs; and the likely strength of the impact of a belief on the behaviour. Results Eight physicians from four of the intervention sites in the Canadian CT Head Rule trial participated in the interviews. Barriers

Theoretical prediction of the mechanical properties of zeolitic imidazolate frameworks (ZIFs)

KAUST Repository

Zheng, Bin; Zhu, Yihan; Fu, Fang; Wang, Lian Li; Wang, Jinlei; Du, Huiling

2017-01-01

A good resistance against mechanical stress is essential for the utilization of metal-organic frameworks (MOFs) in practical applications such as gas sorption, separation, catalysis or energy conversion. Here, we report on the successful modification of the mechanical properties of zeolitic imidazolate frameworks (ZIFs) achieved through a substitution of the terminal group. The mechanical modulus of SALEM-2 was found to significantly improve when the -H groups at position 2 of the imidazole linkers were replaced with electron withdrawing groups (-CHO, -Cl, or -Br). The charge distribution and electron density were analyzed to reveal the mechanism behind the observed variation of the elastic stiffness. Furthermore, ZIF-I with a -I group at position 2 of the imidazole linkers was predicted to exhibit an excellent mechanical strength in our study and then prepared experimentally. The results indicate that an inconspicuous change of the structure of ZIFs, i.e., additional groups strengthening the ZnN4 tetrahedron, will lead to a stiffer framework.

Theoretical prediction of the mechanical properties of zeolitic imidazolate frameworks (ZIFs)

KAUST Repository

Zheng, Bin

2017-08-25

A good resistance against mechanical stress is essential for the utilization of metal-organic frameworks (MOFs) in practical applications such as gas sorption, separation, catalysis or energy conversion. Here, we report on the successful modification of the mechanical properties of zeolitic imidazolate frameworks (ZIFs) achieved through a substitution of the terminal group. The mechanical modulus of SALEM-2 was found to significantly improve when the -H groups at position 2 of the imidazole linkers were replaced with electron withdrawing groups (-CHO, -Cl, or -Br). The charge distribution and electron density were analyzed to reveal the mechanism behind the observed variation of the elastic stiffness. Furthermore, ZIF-I with a -I group at position 2 of the imidazole linkers was predicted to exhibit an excellent mechanical strength in our study and then prepared experimentally. The results indicate that an inconspicuous change of the structure of ZIFs, i.e., additional groups strengthening the ZnN4 tetrahedron, will lead to a stiffer framework.

Gradient waveform synthesis for magnetic propulsion using MRI gradient coils

International Nuclear Information System (INIS)

Han, B H; Lee, S Y; Park, S

2008-01-01

Navigating an untethered micro device in a living subject is of great interest for both diagnostic and therapeutic applications. Magnetic propulsion of an untethered device carrying a magnetic core in it is one of the promising methods to navigate the device. MRI gradients coils are thought to be suitable for navigating the device since they are capable of magnetic propulsion in any direction while providing magnetic resonance images. For precise navigation of the device, especially in the peripheral region of the gradient coils, the concomitant gradient fields, as well as the linear gradient fields in the main magnetic field direction, should be considered in driving the gradient coils. For simple gradient coil configurations, the Maxwell coil in the z-direction and the Golay coil in the x- and y-directions, we have calculated the magnetic force fields, which are not necessarily the same as the conventional linear gradient fields of MRI. Using the calculated magnetic force fields, we have synthesized gradient waveforms to navigate the device along a desired path

Unsupervised active learning based on hierarchical graph-theoretic clustering.

Science.gov (United States)

Hu, Weiming; Hu, Wei; Xie, Nianhua; Maybank, Steve

2009-10-01

Most existing active learning approaches are supervised. Supervised active learning has the following problems: inefficiency in dealing with the semantic gap between the distribution of samples in the feature space and their labels, lack of ability in selecting new samples that belong to new categories that have not yet appeared in the training samples, and lack of adaptability to changes in the semantic interpretation of sample categories. To tackle these problems, we propose an unsupervised active learning framework based on hierarchical graph-theoretic clustering. In the framework, two promising graph-theoretic clustering algorithms, namely, dominant-set clustering and spectral clustering, are combined in a hierarchical fashion. Our framework has some advantages, such as ease of implementation, flexibility in architecture, and adaptability to changes in the labeling. Evaluations on data sets for network intrusion detection, image classification, and video classification have demonstrated that our active learning framework can effectively reduce the workload of manual classification while maintaining a high accuracy of automatic classification. It is shown that, overall, our framework outperforms the support-vector-machine-based supervised active learning, particularly in terms of dealing much more efficiently with new samples whose categories have not yet appeared in the training samples.

Potential determinants of health-care professionals' use of survivorship care plans: a qualitative study using the theoretical domains framework.

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Birken, Sarah A; Presseau, Justin; Ellis, Shellie D; Gerstel, Adrian A; Mayer, Deborah K

2014-11-15

Survivorship care plans are intended to improve coordination of care for the nearly 14 million cancer survivors in the United States. Evidence suggests that survivorship care plans (SCPs) have positive outcomes for survivors, health-care professionals, and cancer programs, and several high-profile organizations now recommend SCP use. Nevertheless, SCP use remains limited among health-care professionals in United States cancer programs. Knowledge of barriers to SCP use is limited in part because extant studies have used anecdotal evidence to identify determinants. This study uses the theoretical domains framework to identify relevant constructs that are potential determinants of SCP use among United States health-care professionals. We conducted semi-structured interviews to assess the relevance of 12 theoretical domains in predicting SCP use among 13 health-care professionals in 7 cancer programs throughout the United States with diverse characteristics. Relevant theoretical domains were identified through thematic coding of interview transcripts, identification of specific beliefs within coded text units, and mapping of specific beliefs onto theoretical constructs. We found the following theoretical domains (based on specific beliefs) to be potential determinants of SCP use: health-care professionals' beliefs about the consequences of SCP use (benefit to survivors, health-care professionals, and the system as a whole); motivation and goals regarding SCP use (advocating SCP use; extent to which using SCPs competed for health-care professionals' time); environmental context and resources (whether SCPs were delivered at a dedicated visit and whether a system, information technology, and funding facilitated SCP use); and social influences (whether using SCPs is an organizational priority, influential people support SCP use, and people who could assist with SCP use buy into using SCPs). Specific beliefs mapped onto the following psychological constructs: outcome

Combining Step Gradients and Linear Gradients in Density.

Science.gov (United States)

Kumar, Ashok A; Walz, Jenna A; Gonidec, Mathieu; Mace, Charles R; Whitesides, George M

2015-06-16

Combining aqueous multiphase systems (AMPS) and magnetic levitation (MagLev) provides a method to produce hybrid gradients in apparent density. AMPS—solutions of different polymers, salts, or surfactants that spontaneously separate into immiscible but predominantly aqueous phases—offer thermodynamically stable steps in density that can be tuned by the concentration of solutes. MagLev—the levitation of diamagnetic objects in a paramagnetic fluid within a magnetic field gradient—can be arranged to provide a near-linear gradient in effective density where the height of a levitating object above the surface of the magnet corresponds to its density; the strength of the gradient in effective density can be tuned by the choice of paramagnetic salt and its concentrations and by the strength and gradient in the magnetic field. Including paramagnetic salts (e.g., MnSO4 or MnCl2) in AMPS, and placing them in a magnetic field gradient, enables their use as media for MagLev. The potential to create large steps in density with AMPS allows separations of objects across a range of densities. The gradients produced by MagLev provide resolution over a continuous range of densities. By combining these approaches, mixtures of objects with large differences in density can be separated and analyzed simultaneously. Using MagLev to add an effective gradient in density also enables tuning the range of densities captured at an interface of an AMPS by simply changing the position of the container in the magnetic field. Further, by creating AMPS in which phases have different concentrations of paramagnetic ions, the phases can provide different resolutions in density. These results suggest that combining steps in density with gradients in density can enable new classes of separations based on density.

Full-angle Negative Reflection with An Ultrathin Acoustic Gradient Metasurface: Floquet-Bloch Modes Perspective and Experimental Verification

KAUST Repository

Liu, Bingyi

2017-07-01

Metasurface with gradient phase response offers new alternative for steering the propagation of waves. Conventional Snell\\'s law has been revised by taking the contribution of local phase gradient into account. However, the requirement of momentum matching along the metasurface sets its nontrivial beam manipulation functionality within a limited-angle incidence. In this work, we theoretically and experimentally demonstrate that the acoustic gradient metasurface supports the negative reflection for full-angle incidence. The mode expansion theory is developed to help understand how the gradient metasurface tailors the incident beams, and the full-angle negative reflection occurs when the first negative order Floquet-Bloch mode dominates. The coiling-up space structures are utilized to build desired acoustic gradient metasurface and the full-angle negative reflections have been perfectly verified by experimental measurements. Our work offers the Floquet-Bloch modes perspective for qualitatively understanding the reflection behaviors of the acoustic gradient metasurface and enables a new degree of the acoustic wave manipulating.

Information theoretic quantification of diagnostic uncertainty.

Science.gov (United States)

Westover, M Brandon; Eiseman, Nathaniel A; Cash, Sydney S; Bianchi, Matt T

2012-01-01

Diagnostic test interpretation remains a challenge in clinical practice. Most physicians receive training in the use of Bayes' rule, which specifies how the sensitivity and specificity of a test for a given disease combine with the pre-test probability to quantify the change in disease probability incurred by a new test result. However, multiple studies demonstrate physicians' deficiencies in probabilistic reasoning, especially with unexpected test results. Information theory, a branch of probability theory dealing explicitly with the quantification of uncertainty, has been proposed as an alternative framework for diagnostic test interpretation, but is even less familiar to physicians. We have previously addressed one key challenge in the practical application of Bayes theorem: the handling of uncertainty in the critical first step of estimating the pre-test probability of disease. This essay aims to present the essential concepts of information theory to physicians in an accessible manner, and to extend previous work regarding uncertainty in pre-test probability estimation by placing this type of uncertainty within a principled information theoretic framework. We address several obstacles hindering physicians' application of information theoretic concepts to diagnostic test interpretation. These include issues of terminology (mathematical meanings of certain information theoretic terms differ from clinical or common parlance) as well as the underlying mathematical assumptions. Finally, we illustrate how, in information theoretic terms, one can understand the effect on diagnostic uncertainty of considering ranges instead of simple point estimates of pre-test probability.

Interrelationship between flexoelectricity and strain gradient elasticity in ferroelectric nanofilms: A phase field study

Science.gov (United States)

Jiang, Limei; Xu, Xiaofei; Zhou, Yichun

2016-12-01

With the development of the integrated circuit technology and decreasing of the device size, ferroelectric films used in nano ferroelectric devices become thinner and thinner. Along with the downscaling of the ferroelectric film, there is an increasing influence of two strain gradient related terms. One is the strain gradient elasticity and the other one is flexoelectricity. To investigate the interrelationship between flexoelectricity and strain gradient elasticity and their combined effect on the domain structure in ferroelectric nanofilms, a phase field model of flexoelectricity and strain gradient elasticity on the ferroelectric domain evolution is developed based on Mindlin's theory of strain-gradient elasticity. Weak form is derived and implemented in finite element formulations for numerically solving the model equations. The simulation results show that upper bounds for flexoelectric coefficients can be enhanced by increasing strain gradient elasticity coefficients. While a large flexoelectricity that exceeds the upper bound can induce a transition from a ferroelectric state to a modulated/incommensurate state, a large enough strain gradient elasticity may lead to a conversion from an incommensurate state to a ferroelectric state. Strain gradient elasticity and the flexoelectricity have entirely opposite effects on polarization. The observed interrelationship between the strain gradient elasticity and flexoelectricity is rationalized by an analytical solution of the proposed theoretical model. The model proposed in this paper could help us understand the mechanism of phenomena observed in ferroelectric nanofilms under complex electromechanical loads and provide some guides on the practical application of ferroelectric nanofilms.

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

Science.gov (United States)

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…

Does Hunger Contribute to Socioeconomic Gradients in Behavior?

Science.gov (United States)

Nettle, Daniel

2017-01-01

Recent research has uncovered many examples of socioeconomic gradients in behavior and psychological states. As yet there is no theoretical consensus on the nature of the causal processes that produce these gradients. Here, I present the hunger hypothesis, namely the claim that part of the reason that people of lower socioeconomic position behave and feel as they do is that they are relatively often hungry. The hunger hypothesis applies in particular to impulsivity-hyperactivity, irritability-aggression, anxiety, and persistent narcotic use, all of which have been found to show socioeconomic gradients. I review multiple lines of evidence showing that hunger produces strong increases in these outcomes. I also review the literatures on food insufficiency and food insecurity to show that, within affluent societies, the poor experience a substantial burden of hunger, despite obtaining sufficient or excess calories on average. This leads to the distinctive prediction that hunger is an important mediator of the relationships between socioeconomic variables and the behavioral/psychological outcomes. This approach has a number of far-reaching implications, not least that some behavioral and psychological differences between social groups, though persistent under current economic arrangements, are potentially highly reversible with changes to the distribution of financial resources and food. PMID:28344567

An Evaluation Use Framework and Empirical Assessment

Science.gov (United States)

Peck, Laura R.; Gorzalski, Lindsey M.

2009-01-01

Background: Research on evaluation use focuses on putting evaluation recommendations into practice. Prior theoretical research proposes varied frameworks for understanding the use (or lack) of program evaluation results. Purpose: Our purpose is to create and test a single, integrated framework for understanding evaluation use. This article relies…

A framework of manufacturer-retailer coordination process

DEFF Research Database (Denmark)

Wong, Chee Yew; Johansen, John

2008-01-01

Purpose - Triggered by perceived inefficiency and inequality, buyers and suppliers coordinate with each other. The purpose of this paper is to develop a framework of coordination process based on theoretical review and verifications from three case studies. Design/methodology/approach - The appro......Purpose - Triggered by perceived inefficiency and inequality, buyers and suppliers coordinate with each other. The purpose of this paper is to develop a framework of coordination process based on theoretical review and verifications from three case studies. Design...... there was disagreement. Third, closer mode of coordination, which involved joint evaluation and derivation of coordination solutions, reduced the numbers of iterative coordination cycles. These empirical findings verified the presupposed framework of coordination process. Research limitations/implications - Three...... qualitative case studies may not be highly generalisable and multiple dyadic coordination processes may occur. However, the findings form a foundation for further understanding of the coordination process. Originality/value - The proposed framework of the coordination process further expands the theories...

Momentum-weighted conjugate gradient descent algorithm for gradient coil optimization.

Science.gov (United States)

Lu, Hanbing; Jesmanowicz, Andrzej; Li, Shi-Jiang; Hyde, James S

2004-01-01

MRI gradient coil design is a type of nonlinear constrained optimization. A practical problem in transverse gradient coil design using the conjugate gradient descent (CGD) method is that wire elements move at different rates along orthogonal directions (r, phi, z), and tend to cross, breaking the constraints. A momentum-weighted conjugate gradient descent (MW-CGD) method is presented to overcome this problem. This method takes advantage of the efficiency of the CGD method combined with momentum weighting, which is also an intrinsic property of the Levenberg-Marquardt algorithm, to adjust step sizes along the three orthogonal directions. A water-cooled, 12.8 cm inner diameter, three axis torque-balanced gradient coil for rat imaging was developed based on this method, with an efficiency of 2.13, 2.08, and 4.12 mT.m(-1).A(-1) along X, Y, and Z, respectively. Experimental data demonstrate that this method can improve efficiency by 40% and field uniformity by 27%. This method has also been applied to the design of a gradient coil for the human brain, employing remote current return paths. The benefits of this design include improved gradient field uniformity and efficiency, with a shorter length than gradient coil designs using coaxial return paths. Copyright 2003 Wiley-Liss, Inc.

Self, College Experiences, and Society: Rethinking the Theoretical Foundations of Student Development Theory

Science.gov (United States)

Winkle-Wagner, Rachelle

2012-01-01

This article examines the psychological theoretical foundations of college student development theory and the theoretical assumptions of this framework. A complimentary, sociological perspective and the theoretical assumptions of this approach are offered. The potential limitations of the overuse of each perspective are considered. The conclusion…

Information Theoretic-Learning Auto-Encoder

OpenAIRE

Santana, Eder; Emigh, Matthew; Principe, Jose C

2016-01-01

We propose Information Theoretic-Learning (ITL) divergence measures for variational regularization of neural networks. We also explore ITL-regularized autoencoders as an alternative to variational autoencoding bayes, adversarial autoencoders and generative adversarial networks for randomly generating sample data without explicitly defining a partition function. This paper also formalizes, generative moment matching networks under the ITL framework.

‘It’s a can of worms’: understanding primary care practitioners’ behaviours in relation to HPV using the theoretical domains framework

Directory of Open Access Journals (Sweden)

McSherry Lisa A

2012-08-01

Full Text Available Abstract Background The relationship between infection with high-risk human papillomavirus (HPV and cervical cancer is transforming cervical cancer prevention. HPV tests and vaccinations have recently become available. In Ireland, as elsewhere, primary care practitioners play a key role in prevention. ATHENS (A Trial of HPV Education and Support aims to develop a theory-based intervention to support primary care practitioners in their HPV-related practice. This study, the first step in the intervention development process, aimed to: identify HPV-related clinical behaviours that the intervention will target; clarify general practitioners’ (GPs’ and practice nurses’ roles and responsibilities; and determine factors that potentially influence clinical behaviour. A secondary objective was to informally assess the utility of the Theoretical Domains Framework (TDF in understanding clinical behaviours in an area with an evolving evidence-base. Methods In-depth semi-structured telephone interviews were conducted with GPs and practice nurses. The topic guide, which contained open questions and HPV-related clinical scenarios, was developed through literature review and clinical experience. Interview transcripts were content-analysed using the TDF as the coding framework. Results 19 GPs and 14 practice nurses were interviewed. The major HPV-related clinical behaviours were: initiating a discussion about HPV infection with female patients; offering/recommending HPV vaccination to appropriate patients; and answering patients’ questions about HPV testing. While the responsibility for taking smears was considered a female role, both male and female practitioners dealt with HPV-related issues. All 12 theoretical domains arose in relation to HPV infection; the domains judged to be most important were: knowledge, emotion, social influences, beliefs about capabilities and beliefs about consequences. Eleven domains emerged in relation to HPV vaccination

The influence of precipitation kinetics on trace element partitioning between solid and liquid solutions: A coupled fluid dynamics/thermodynamics framework to predict distribution coefficients

Science.gov (United States)

Kavner, A.

2017-12-01

In a multicomponent multiphase geochemical system undergoing a chemical reaction such as precipitation and/or dissolution, the partitioning of species between phases is determined by a combination of thermodynamic properties and transport processes. The interpretation of the observed distribution of trace elements requires models integrating coupled chemistry and mechanical transport. Here, a framework is presented that predicts the kinetic effects on the distribution of species between two reacting phases. Based on a perturbation theory combining Navier-Stokes fluid flow and chemical reactivity, the framework predicts rate-dependent partition coefficients in a variety of different systems. We present the theoretical framework, with applications to two systems: 1. species- and isotope-dependent Soret diffusion of species in a multicomponent silicate melt subjected to a temperature gradient, and 2. Elemental partitioning and isotope fractionation during precipitation of a multicomponent solid from a multicomponent liquid phase. Predictions will be compared with results from experimental studies. The approach has applications for understanding chemical exchange in at boundary layers such as the Earth's surface magmatic systems and at the core/mantle boundary.

Systems View of School Climate: A Theoretical Framework for Research

Science.gov (United States)

Rudasill, Kathleen Moritz; Snyder, Kate E.; Levinson, Heather; Adelson, Jill L.

2018-01-01

School climate has been widely examined through both empirical and theoretical means. However, there is little conceptual consensus underlying the landscape of this literature, offering inconsistent guidance for research examining this important construct. In order to best assist the efforts of developing causal models that describe how school…

The chirped-pulse inverse free-electron laser: A high-gradient vacuum laser accelerator

International Nuclear Information System (INIS)

Hartemann, F.V.; Landahl, E.C.; Troha, A.L.; Van Meter, J.R.; Baldis, H.A.; Freeman, R.R.; Luhmann, N.C. Jr.; Song, L.; Kerman, A.K.; Yu, D.U.

1999-01-01

The inverse free-electron laser (IFEL) interaction is studied theoretically and computationally in the case where the drive laser intensity approaches the relativistic regime, and the pulse duration is only a few optical cycles long. The IFEL concept has been demonstrated as a viable vacuum laser acceleration process; it is shown here that by using an ultrashort, ultrahigh-intensity drive laser pulse, the IFEL interaction bandwidth and accelerating gradient are increased considerably, thus yielding large energy gains. Using a chirped pulse and negative dispersion focusing optics allows one to take further advantage of the laser optical bandwidth and produce a chromatic line focus maximizing the gradient. The combination of these novel ideas results in a compact vacuum laser accelerator capable of accelerating picosecond electron bunches with a high gradient (GeV/m) and very low energy spread. copyright 1999 American Institute of Physics

Assessing two Theoretical Frameworks of Civic Engagement

Directory of Open Access Journals (Sweden)

Benilde García-Cabrero

2016-03-01

Full Text Available The purpose of this study was to empirically test two major theoretical models: a modified version of the social capital model (Pattie, Seyd and Whiteley, 2003, and the Informed Social Engagement Model (Barr and Selman, 2014; Selman and Kwok, 2010, to explain civic participation and civic knowledge of adolescents from Chile, Colombia and Mexico, using data from the International Civic and Citizenship Education Study 2009 (Schulz, et al., 2010. The models were used to identify factors associated with different levels of knowledge and civic participation: expected participation in legal and illegal protests, and electoral participation. Data were analyzed using regression analysis. Results show that the Informed Social Engagement approach (ISEM, explains better the observed differences in civic knowledge and civic participation, than the Social Capital Model (SCM. That is, the expected values associated with the variables included in the ISEM are closer to the observed values, than those predicted by the SCM. This is true for the three outcomes (expected participation in legal protests, illegal protests, and electoral participation and in the three countries analyzed (Chile, Colombia and Mexico.

A new pressure ulcer conceptual framework

Science.gov (United States)

Coleman, Susanne; Nixon, Jane; Keen, Justin; Wilson, Lyn; McGinnis, Elizabeth; Dealey, Carol; Stubbs, Nikki; Farrin, Amanda; Dowding, Dawn; Schols, Jos MGA; Cuddigan, Janet; Berlowitz, Dan; Jude, Edward; Vowden, Peter; Schoonhoven, Lisette; Bader, Dan L; Gefen, Amit; Oomens, Cees WJ; Nelson, E Andrea

2014-01-01

Aim This paper discusses the critical determinants of pressure ulcer development and proposes a new pressure ulcer conceptual framework. Background Recent work to develop and validate a new evidence-based pressure ulcer risk assessment framework was undertaken. This formed part of a Pressure UlceR Programme Of reSEarch (RP-PG-0407-10056), funded by the National Institute for Health Research. The foundation for the risk assessment component incorporated a systematic review and a consensus study that highlighted the need to propose a new conceptual framework. Design Discussion Paper. Data Sources The new conceptual framework links evidence from biomechanical, physiological and epidemiological evidence, through use of data from a systematic review (search conducted March 2010), a consensus study (conducted December 2010–2011) and an international expert group meeting (conducted December 2011). Implications for Nursing A new pressure ulcer conceptual framework incorporating key physiological and biomechanical components and their impact on internal strains, stresses and damage thresholds is proposed. Direct and key indirect causal factors suggested in a theoretical causal pathway are mapped to the physiological and biomechanical components of the framework. The new proposed conceptual framework provides the basis for understanding the critical determinants of pressure ulcer development and has the potential to influence risk assessment guidance and practice. It could also be used to underpin future research to explore the role of individual risk factors conceptually and operationally. Conclusion By integrating existing knowledge from epidemiological, physiological and biomechanical evidence, a theoretical causal pathway and new conceptual framework are proposed with potential implications for practice and research. PMID:24684197

A new pressure ulcer conceptual framework.

Science.gov (United States)

Coleman, Susanne; Nixon, Jane; Keen, Justin; Wilson, Lyn; McGinnis, Elizabeth; Dealey, Carol; Stubbs, Nikki; Farrin, Amanda; Dowding, Dawn; Schols, Jos M G A; Cuddigan, Janet; Berlowitz, Dan; Jude, Edward; Vowden, Peter; Schoonhoven, Lisette; Bader, Dan L; Gefen, Amit; Oomens, Cees W J; Nelson, E Andrea

2014-10-01

This paper discusses the critical determinants of pressure ulcer development and proposes a new pressure ulcer conceptual framework. Recent work to develop and validate a new evidence-based pressure ulcer risk assessment framework was undertaken. This formed part of a Pressure UlceR Programme Of reSEarch (RP-PG-0407-10056), funded by the National Institute for Health Research. The foundation for the risk assessment component incorporated a systematic review and a consensus study that highlighted the need to propose a new conceptual framework. Discussion Paper. The new conceptual framework links evidence from biomechanical, physiological and epidemiological evidence, through use of data from a systematic review (search conducted March 2010), a consensus study (conducted December 2010-2011) and an international expert group meeting (conducted December 2011). A new pressure ulcer conceptual framework incorporating key physiological and biomechanical components and their impact on internal strains, stresses and damage thresholds is proposed. Direct and key indirect causal factors suggested in a theoretical causal pathway are mapped to the physiological and biomechanical components of the framework. The new proposed conceptual framework provides the basis for understanding the critical determinants of pressure ulcer development and has the potential to influence risk assessment guidance and practice. It could also be used to underpin future research to explore the role of individual risk factors conceptually and operationally. By integrating existing knowledge from epidemiological, physiological and biomechanical evidence, a theoretical causal pathway and new conceptual framework are proposed with potential implications for practice and research. © 2014 The Authors. Journal of Advanced Nursing Published by John Wiley & Sons Ltd.

MATLAB Simulation of Gradient-Based Neural Network for Online Matrix Inversion

Science.gov (United States)

Zhang, Yunong; Chen, Ke; Ma, Weimu; Li, Xiao-Dong

This paper investigates the simulation of a gradient-based recurrent neural network for online solution of the matrix-inverse problem. Several important techniques are employed as follows to simulate such a neural system. 1) Kronecker product of matrices is introduced to transform a matrix-differential-equation (MDE) to a vector-differential-equation (VDE); i.e., finally, a standard ordinary-differential-equation (ODE) is obtained. 2) MATLAB routine "ode45" is introduced to solve the transformed initial-value ODE problem. 3) In addition to various implementation errors, different kinds of activation functions are simulated to show the characteristics of such a neural network. Simulation results substantiate the theoretical analysis and efficacy of the gradient-based neural network for online constant matrix inversion.

Potential benefits of remote sensing: Theoretical framework and empirical estimate

Science.gov (United States)

Eisgruber, L. M.

1972-01-01

A theoretical framwork is outlined for estimating social returns from research and application of remote sensing. The approximate dollar magnitude is given of a particular application of remote sensing, namely estimates of corn production, soybeans, and wheat. Finally, some comments are made on the limitations of this procedure and on the implications of results.

X-ray stress analysis of residual stress gradients in surface layers of steel

International Nuclear Information System (INIS)

Ganev, N.; Kraus, I.; Gosmanova, G.; Pfeiffer, L.; Tietz, H.-D.

2001-01-01

The aim of the contribution is to present the theoretical possibilities of X-ray non-destructive identification of stress gradients within the penetration depth of used radiation and its utilization for experimental stress analysis. Practical usefullness of outlined speculations is illustrated with results of stress measurements on cut and shot-penned steel samples. (author)

Theoretical Foundations of Active Learning

Science.gov (United States)

2009-05-01

I study the informational complexity of active learning in a statistical learning theory framework. Specifically, I derive bounds on the rates of...convergence achievable by active learning , under various noise models and under general conditions on the hypothesis class. I also study the theoretical...advantages of active learning over passive learning, and develop procedures for transforming passive learning algorithms into active learning algorithms

Adaptation of the methodological instrument of the representation of the content (CORE to the theoretical framework of TPCK

Directory of Open Access Journals (Sweden)

Boris Fernando Candela

2017-07-01

Full Text Available Since the middle of the eighties the community in science education has been interested in teachers to identify and develop the Content Pedagogical Knowledge (PCK. To this end, it has designed educational programs from a “reflective orientation” perspective structured from a set of training activities whose tasks are focused on the practice of designing specific content learning environments, where the methodological instrument of the Representation of Content (CoRe has played a critical role. The logical structure of it provides the possibility for teachers to become aware of the theoretical and methodological elements that underpin the PCK. On the other hand, with the emergence of digital technologies as an instrument for representing content and effective management of the classroom, the need to transform the construct of the Content Pedagogical Knowledge (PCK to the Technological and Pedagogical Knowledge of the content is generated (TPCK. In this sense, it is pertinent to adapt the epistemological structure of the CoRe to the theoretical framework of the emerging construct of the TPCK, in order that this instrument continue to be used as a key heuristic in education programs where the practice of designing environments Learning is important for the professional development of teachers. Of course, the adaptation of the CoRe to the perspective of the TPCK is accompanied by a conceptualization of each of the twelve items that configure it, in order to illustrate the teachers during their development.

A theoretical framework informing research about the role of stress in the pathophysiology of bipolar disorder.

Science.gov (United States)

Brietzke, Elisa; Mansur, Rodrigo Barbachan; Soczynska, Joanna; Powell, Alissa M; McIntyre, Roger S

2012-10-01

The staggering illness burden associated with Bipolar Disorder (BD) invites the need for primary prevention strategies. Before preventative strategies can be considered in individuals during a pre-symptomatic period (i.e., at risk), unraveling the mechanistic steps wherein external stress is transduced and interacts with genetic vulnerability in the early stages of BD will be a critical conceptual necessity. Herein we comprehensively review extant studies reporting on stress and bipolar disorder. The overarching aim is to propose a conceptual framework to inform research about the role of stress in the pathophysiology of BD. Computerized databases i.e. PubMed, PsychInfo, Cochrane Library and Scielo were searched using the following terms: "bipolar disorder" cross-referenced with "stress", "general reaction to stress", "resilience", "resistance", "recovery" "stress-diathesis", "allostasis", and "hormesis". Data from literature indicate the existence of some theoretical models to understand the influence of stress in the pathophysiology of BD, including classical stress-diathesis model and new models such as allostasis and hormesis. In addition, molecular mechanisms involved in stress adaptation (resistance, resilience and recovery) can also be translated in research strategies to investigate the impact of stress in the pathophysiology of BD. Most studies are retrospective and/or cross sectional, do not consider the period of development, assess brain function with only one or few methodologies, and use animal models which are not always similar to human phenotypes. The interaction between stress and brain development is dynamic and complex. In this article we proposed a theoretical model for investigation about the role of stress in the pathophysiology of BD, based on the different kinds of stress adaptation response and their putative neurobiological underpinnings. Copyright © 2012 Elsevier Inc. All rights reserved.

A Symbiotic Framework for coupling Machine Learning and Geosciences in Prediction and Predictability

Science.gov (United States)

Ravela, S.

2017-12-01

In this presentation we review the two directions of a symbiotic relationship between machine learning and the geosciences in relation to prediction and predictability. In the first direction, we develop ensemble, information theoretic and manifold learning framework to adaptively improve state and parameter estimates in nonlinear high-dimensional non-Gaussian problems, showing in particular that tractable variational approaches can be produced. We demonstrate these applications in the context of autonomous mapping of environmental coherent structures and other idealized problems. In the reverse direction, we show that data assimilation, particularly probabilistic approaches for filtering and smoothing offer a novel and useful way to train neural networks, and serve as a better basis than gradient based approaches when we must quantify uncertainty in association with nonlinear, chaotic processes. In many inference problems in geosciences we seek to build reduced models to characterize local sensitivies, adjoints or other mechanisms that propagate innovations and errors. Here, the particular use of neural approaches for such propagation trained using ensemble data assimilation provides a novel framework. Through these two examples of inference problems in the earth sciences, we show that not only is learning useful to broaden existing methodology, but in reverse, geophysical methodology can be used to influence paradigms in learning.

Peer-Formativity: A Framework for Academic Writing

Science.gov (United States)

Murray, Rowena; Thow, Morag

2014-01-01

The system currently deployed to assess research outputs in higher education can influence what, how and for whom academics write; for some it may determine whether or not they write at all. This article offers a framework for negotiating this performative context--the writing meeting. This framework uses the established theoretical underpinning…

Redesigning Orientation in an Intensive Care Unit Using 2 Theoretical Models.

Science.gov (United States)

Kozub, Elizabeth; Hibanada-Laserna, Maribel; Harget, Gwen; Ecoff, Laurie

2015-01-01

To accommodate a higher demand for critical care nurses, an orientation program in a surgical intensive care unit was revised and streamlined. Two theoretical models served as a foundation for the revision and resulted in clear clinical benchmarks for orientation progress evaluation. The purpose of the project was to integrate theoretical frameworks into practice to improve the unit orientation program. Performance improvement methods served as a framework for the revision, and outcomes were measured before and after implementation. The revised orientation program increased 1- and 2-year nurse retention and decreased turnover. Critical care knowledge increased after orientation for both the preintervention and postintervention groups. Incorporating a theoretical basis for orientation has been shown to be successful in increasing the number of nurses completing orientation and improving retention, turnover rates, and knowledge gained.

Women's career advancement in organisations: Integrative framework for research

Directory of Open Access Journals (Sweden)

Mišić-Andrić Marijana

2015-01-01

Full Text Available Contemporary organisations, caught in the middle of global economic and social crisis, are facing different business challenges, having to respond to quick changes in business environment and demographic changes in workforce composed by increasing number of women. Although the number of women in workforce is on the rise, they are still underrepresented in manager positions, especially higher management. This implies that certain barriers are in place which makes difficult for women to develop their careers, especially in reaching manager positions. The aim of this paper is to analyse and present a theoretical framework for further study of professional carrier advancement for women. The paper especially analyse integrative theoretical framework which stresses the equal importance of researching individual factors (personal influence and organisational factors (social inclusion, having in mind how the organisational context can improve or deter women's carrier. The paper presents possible directions for future research based on the analysis of the theoretical framework and especially individual and organisational factors.

Decision support models for solid waste management: Review and game-theoretic approaches

International Nuclear Information System (INIS)

Karmperis, Athanasios C.; Aravossis, Konstantinos; Tatsiopoulos, Ilias P.; Sotirchos, Anastasios

2013-01-01

Highlights: ► The mainly used decision support frameworks for solid waste management are reviewed. ► The LCA, CBA and MCDM models are presented and their strengths, weaknesses, similarities and possible combinations are analyzed. ► The game-theoretic approach in a solid waste management context is presented. ► The waste management bargaining game is introduced as a specific decision support framework. ► Cooperative and non-cooperative game-theoretic approaches to decision support for solid waste management are discussed. - Abstract: This paper surveys decision support models that are commonly used in the solid waste management area. Most models are mainly developed within three decision support frameworks, which are the life-cycle assessment, the cost–benefit analysis and the multi-criteria decision-making. These frameworks are reviewed and their strengths and weaknesses as well as their critical issues are analyzed, while their possible combinations and extensions are also discussed. Furthermore, the paper presents how cooperative and non-cooperative game-theoretic approaches can be used for the purpose of modeling and analyzing decision-making in situations with multiple stakeholders. Specifically, since a waste management model is sustainable when considering not only environmental and economic but also social aspects, the waste management bargaining game is introduced as a specific decision support framework in which future models can be developed

Decision support models for solid waste management: Review and game-theoretic approaches

Energy Technology Data Exchange (ETDEWEB)

Karmperis, Athanasios C., E-mail: athkarmp@mail.ntua.gr [Sector of Industrial Management and Operational Research, School of Mechanical Engineering, National Technical University of Athens, Iroon Polytechniou 9, 15780 Athens (Greece); Army Corps of Engineers, Hellenic Army General Staff, Ministry of Defence (Greece); Aravossis, Konstantinos; Tatsiopoulos, Ilias P.; Sotirchos, Anastasios [Sector of Industrial Management and Operational Research, School of Mechanical Engineering, National Technical University of Athens, Iroon Polytechniou 9, 15780 Athens (Greece)

2013-05-15

Highlights: ► The mainly used decision support frameworks for solid waste management are reviewed. ► The LCA, CBA and MCDM models are presented and their strengths, weaknesses, similarities and possible combinations are analyzed. ► The game-theoretic approach in a solid waste management context is presented. ► The waste management bargaining game is introduced as a specific decision support framework. ► Cooperative and non-cooperative game-theoretic approaches to decision support for solid waste management are discussed. - Abstract: This paper surveys decision support models that are commonly used in the solid waste management area. Most models are mainly developed within three decision support frameworks, which are the life-cycle assessment, the cost–benefit analysis and the multi-criteria decision-making. These frameworks are reviewed and their strengths and weaknesses as well as their critical issues are analyzed, while their possible combinations and extensions are also discussed. Furthermore, the paper presents how cooperative and non-cooperative game-theoretic approaches can be used for the purpose of modeling and analyzing decision-making in situations with multiple stakeholders. Specifically, since a waste management model is sustainable when considering not only environmental and economic but also social aspects, the waste management bargaining game is introduced as a specific decision support framework in which future models can be developed.

Stimulating technological innovation : problem identification and intervention formulation with the technological innovation systems framework

OpenAIRE

Kieft, A.C.

2017-01-01

The technological innovation systems (TIS) framework provides a theory to understand under what conditions technological innovations are successfully developed and implemented. The objective of this dissertation is to further strengthen this TIS intervention framework, which is the part of the TIS theoretical framework that facilitates the identification of inhibiting problems and the formulation of interventions. Theoretical adaptations and extensions are proposed and their merits subsequent...

Theoretical Perspectives on the Internationalization of Firms

DEFF Research Database (Denmark)

Rask, Morten; Håkonsson, Dorthe Døjbak; Strandskov, Jesper

2008-01-01

The purpose of this article is to build a coherent framework of the four main theories relating to the internationalization of firms, in order to facilitate better business teaching and research. Yet, theories of the internationalization of firms are broad and rest on different underlying...... assumptions. With the purpose of clarifying the potential for integration of partial theories and fragments in a more logically connected theoretical area, this article offers a meta-theoretical overview of four perspectives within international business economics: Research and its related background, basic...

Gradient Analysis and Classification of Carolina Bay Vegetation: A Framework for Bay Wetlands Conservation and Restoration

Energy Technology Data Exchange (ETDEWEB)

Diane De Steven,Ph.D.; Maureen Tone,PhD.

1997-10-01

This report address four project objectives: (1) Gradient model of Carolina bay vegetation on the SRS--The authors use ordination analyses to identify environmental and landscape factors that are correlated with vegetation composition. Significant factors can provide a framework for site-based conservation of existing diversity, and they may also be useful site predictors for potential vegetation in bay restorations. (2) Regional analysis of Carolina bay vegetation diversity--They expand the ordination analyses to assess the degree to which SRS bays encompass the range of vegetation diversity found in the regional landscape of South Carolina's western Upper Coastal Plain. Such comparisons can indicate floristic status relative to regional potentials and identify missing species or community elements that might be re-introduced or restored. (3) Classification of vegetation communities in Upper Coastal Plain bays--They use cluster analysis to identify plant community-types at the regional scale, and explore how this classification may be functional with respect to significant environmental and landscape factors. An environmentally-based classification at the whole-bay level can provide a system of templates for managing bays as individual units and for restoring bays to desired plant communities. (4) Qualitative model for bay vegetation dynamics--They analyze present-day vegetation in relation to historic land uses and disturbances. The distinctive history of SRS bays provides the possibility of assessing pathways of post-disturbance succession. They attempt to develop a coarse-scale model of vegetation shifts in response to changing site factors; such qualitative models can provide a basis for suggesting management interventions that may be needed to maintain desired vegetation in protected or restored bays.

Carbon dioxide capture using covalent organic frameworks (COFs) type material-a theoretical investigation.

Science.gov (United States)

Dash, Bibek

2018-04-26

The present work deals with a density functional theory (DFT) study of porous organic framework materials containing - groups for CO 2 capture. In this study, first principle calculations were performed for CO 2 adsorption using N-containing covalent organic framework (COFs) models. Ab initio and DFT-based methods were used to characterize the N-containing porous model system based on their interaction energies upon complexing with CO 2 and nitrogen gas. Binding energies (BEs) of CO 2 and N 2 molecules with the polymer framework were calculated with DFT methods. Hybrid B3LYP and second order MP2 methods combined with of Pople 6-31G(d,p) and correlation consistent basis sets cc-pVDZ, cc-pVTZ and aug-ccVDZ were used to calculate BEs. The effect of linker groups in the designed covalent organic framework model system on the CO 2 and N 2 interactions was studied using quantum calculations.

The evolution of conditional dispersal and reproductive isolation along environmental gradients.

Science.gov (United States)

Payne, Joshua L; Mazzucco, Rupert; Dieckmann, Ulf

2011-03-21

Dispersal modulates gene flow throughout a population's spatial range. Gene flow affects adaptation at local spatial scales, and consequently impacts the evolution of reproductive isolation. A recent theoretical investigation has demonstrated that local adaptation along an environmental gradient, facilitated by the evolution of limited dispersal, can lead to parapatric speciation even in the absence of assortative mating. This and other studies assumed unconditional dispersal, so individuals start dispersing without regard to local environmental conditions. However, many species disperse conditionally; their propensity to disperse is contingent upon environmental cues, such as the degree of local crowding or the availability of suitable mates. Here, we use an individual-based model in continuous space to investigate by numerical simulation the relationship between the evolution of threshold-based conditional dispersal and parapatric speciation driven by frequency-dependent competition along environmental gradients. We find that, as with unconditional dispersal, parapatric speciation occurs under a broad range of conditions when reproduction is asexual, and under a more restricted range of conditions when reproduction is sexual. In both the asexual and sexual cases, the evolution of conditional dispersal is strongly influenced by the slope of the environmental gradient: shallow environmental gradients result in low dispersal thresholds and high dispersal distances, while steep environmental gradients result in high dispersal thresholds and low dispersal distances. The latter, however, remain higher than under unconditional dispersal, thus undermining isolation by distance, and hindering speciation in sexual populations. Consequently, the speciation of sexual populations under conditional dispersal is triggered by a steeper gradient than under unconditional dispersal. Enhancing the disruptiveness of frequency-dependent selection, more box-shaped competition kernels

Theoretically informed Monte Carlo simulation of liquid crystals by sampling of alignment-tensor fields

Energy Technology Data Exchange (ETDEWEB)

Armas-Pérez, Julio C.; Londono-Hurtado, Alejandro [Institute for Molecular Engineering, University of Chicago, Chicago, Illinois 60637 (United States); Guzmán, Orlando [Departamento de Física, Universidad Autónoma Metropolitana, Iztapalapa, DF 09340, México (Mexico); Hernández-Ortiz, Juan P. [Departamento de Materiales y Minerales, Universidad Nacional de Colombia, Sede Medellín, Medellín (Colombia); Institute for Molecular Engineering, University of Chicago, Chicago, Illinois 60637 (United States); Pablo, Juan J. de, E-mail: depablo@uchicago.edu [Institute for Molecular Engineering, University of Chicago, Chicago, Illinois 60637 (United States); Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

2015-07-28

A theoretically informed coarse-grained Monte Carlo method is proposed for studying liquid crystals. The free energy functional of the system is described in the framework of the Landau-de Gennes formalism. The alignment field and its gradients are approximated by finite differences, and the free energy is minimized through a stochastic sampling technique. The validity of the proposed method is established by comparing the results of the proposed approach to those of traditional free energy minimization techniques. Its usefulness is illustrated in the context of three systems, namely, a nematic liquid crystal confined in a slit channel, a nematic liquid crystal droplet, and a chiral liquid crystal in the bulk. It is found that for systems that exhibit multiple metastable morphologies, the proposed Monte Carlo method is generally able to identify lower free energy states that are often missed by traditional approaches. Importantly, the Monte Carlo method identifies such states from random initial configurations, thereby obviating the need for educated initial guesses that can be difficult to formulate.

Theoretically informed Monte Carlo simulation of liquid crystals by sampling of alignment-tensor fields.

Energy Technology Data Exchange (ETDEWEB)

Armas-Perez, Julio C.; Londono-Hurtado, Alejandro; Guzman, Orlando; Hernandez-Ortiz, Juan P.; de Pablo, Juan J.

2015-07-27

A theoretically informed coarse-grained Monte Carlo method is proposed for studying liquid crystals. The free energy functional of the system is described in the framework of the Landau-de Gennes formalism. The alignment field and its gradients are approximated by finite differences, and the free energy is minimized through a stochastic sampling technique. The validity of the proposed method is established by comparing the results of the proposed approach to those of traditional free energy minimization techniques. Its usefulness is illustrated in the context of three systems, namely, a nematic liquid crystal confined in a slit channel, a nematic liquid crystal droplet, and a chiral liquid crystal in the bulk. It is found that for systems that exhibit multiple metastable morphologies, the proposed Monte Carlo method is generally able to identify lower free energy states that are often missed by traditional approaches. Importantly, the Monte Carlo method identifies such states from random initial configurations, thereby obviating the need for educated initial guesses that can be difficult to formulate.

Full magnetic gradient tensor from triaxial aeromagnetic gradient measurements: Calculation and application

Science.gov (United States)

Luo, Yao; Wu, Mei-Ping; Wang, Ping; Duan, Shu-Ling; Liu, Hao-Jun; Wang, Jin-Long; An, Zhan-Feng

2015-09-01

The full magnetic gradient tensor (MGT) refers to the spatial change rate of the three field components of the geomagnetic field vector along three mutually orthogonal axes. The tensor is of use to geological mapping, resources exploration, magnetic navigation, and others. However, it is very difficult to measure the full magnetic tensor gradient using existing engineering technology. We present a method to use triaxial aeromagnetic gradient measurements for deriving the full MGT. The method uses the triaxial gradient data and makes full use of the variation of the magnetic anomaly modulus in three dimensions to obtain a self-consistent magnetic tensor gradient. Numerical simulations show that the full MGT data obtained with the proposed method are of high precision and satisfy the requirements of data processing. We selected triaxial aeromagnetic gradient data from the Hebei Province for calculating the full MGT. Data processing shows that using triaxial tensor gradient data allows to take advantage of the spatial rate of change of the total field in three dimensions and suppresses part of the independent noise in the aeromagnetic gradient. The calculated tensor components have improved resolution, and the transformed full tensor gradient satisfies the requirement of geological mapping and interpretation.

Plasma-edge gradients in L-mode and ELM-free H-mode JET plasmas

International Nuclear Information System (INIS)

Breger, P.; Zastrow, K.-D.; Davies, S.J.; K ig, R.W.T.; Summers, D.D.R.; Hellermann, M.G. von; Flewin, C.; Hawkes, N.C.; Pietrzyk, Z.A.; Porte, L.

1998-01-01

Experimental plasma-edge gradients in JET during the edge-localized-mode (ELM) free H-mode are examined for evidence of the presence and location of the transport barrier region inside the magnetic separatrix. High spatial resolution data in electron density is available in- and outside the separatrix from an Li-beam diagnostic, and in electron temperature inside the separatrix from an ECE diagnostic, while outside the separatrix, a reciprocating probe provides electron density and temperature data in the scrape-off layer. Ion temperatures and densities are measured using an edge charge-exchange diagnostic. A comparison of observed widths and gradients of this edge region with each other and with theoretical expectations is made. Measurements show that ions and electrons form different barrier regions. Furthermore, the electron temperature barrier width (3-4 cm) is about twice that of electron density, in conflict with existing scaling laws. Suitable parametrization of the edge data enables an electron pressure gradient to be deduced for the first time at JET. It rises during the ELM-free phase to reach only about half the marginal pressure gradient expected from ballooning stability before the first ELM. Subsequent type I ELMs occur on a pressure gradient contour roughly consistent with both a constant barrier width model and a ballooning mode envelope model. (author)

Theoretical analysis on the refractive-index distribution and bandwidth of gradient-index polymer optical fibers from a centrifugal field.

Science.gov (United States)

Wei, Ming-Hsin; Chen, Wen-Chang

2003-04-20

Theoretical analysis was applied to analyze the refractive-index distribution (RID) and bandwidth (BW) of gradient-index polymer optical fibers (GI POFs) prepared by a centrifugal field process. The RID of the prepared GI POF could be represented by the equation of n(r) = n1[1 - 2delta(r/alpha)g](1/2). The studied material systems were poly(hexafluoroisopropyl 2-fluoroacrylate) (PHFIP 2-FA)/dibutyl phthalate (DBP) and poly(methyl methacrylate) (PMMA)/benzyl benzoate (BEN). The RID and the BW were significantly affected by an essential parameter k, which was related to thematerial properties (density difference and molecular weight) and processing properties (rotating speed, temperature, and radius). As k increased, the characteristic constant of RID, g, decreased to a minimum and then increased sharply, owing to the separation of the polymer and the dopant. On the other hand, the relative refractive-index difference of RID, delta, increased to a steady value after k increased to a certain value. The variation of RID with k resulted in a local minimum of intermodal dispersion, and thus a maximum bandwidth was obtained. The maximum BW of the PHFIP 2-FA/DBP and PMMA/BEN systems at 1550 nm (100-m fiber length and 2-nm spectral width) for the case of k not equal to 0 were 6.7 and 3.2 Gb/s, respectively. The wavelength of light source affects the BW significantly only at k around zero because of the importance of the intramodal dispersion in this case.

An optimization-based framework for anisotropic simplex mesh adaptation

Science.gov (United States)

Yano, Masayuki; Darmofal, David L.

2012-09-01

We present a general framework for anisotropic h-adaptation of simplex meshes. Given a discretization and any element-wise, localizable error estimate, our adaptive method iterates toward a mesh that minimizes error for a given degrees of freedom. Utilizing mesh-metric duality, we consider a continuous optimization problem of the Riemannian metric tensor field that provides an anisotropic description of element sizes. First, our method performs a series of local solves to survey the behavior of the local error function. This information is then synthesized using an affine-invariant tensor manipulation framework to reconstruct an approximate gradient of the error function with respect to the metric tensor field. Finally, we perform gradient descent in the metric space to drive the mesh toward optimality. The method is first demonstrated to produce optimal anisotropic meshes minimizing the L2 projection error for a pair of canonical problems containing a singularity and a singular perturbation. The effectiveness of the framework is then demonstrated in the context of output-based adaptation for the advection-diffusion equation using a high-order discontinuous Galerkin discretization and the dual-weighted residual (DWR) error estimate. The method presented provides a unified framework for optimizing both the element size and anisotropy distribution using an a posteriori error estimate and enables efficient adaptation of anisotropic simplex meshes for high-order discretizations.

Sufficient Descent Conjugate Gradient Methods for Solving Convex Constrained Nonlinear Monotone Equations

Directory of Open Access Journals (Sweden)

San-Yang Liu

2014-01-01

Full Text Available Two unified frameworks of some sufficient descent conjugate gradient methods are considered. Combined with the hyperplane projection method of Solodov and Svaiter, they are extended to solve convex constrained nonlinear monotone equations. Their global convergence is proven under some mild conditions. Numerical results illustrate that these methods are efficient and can be applied to solve large-scale nonsmooth equations.

Understanding end-user support for health information technology: a theoretical framework

Directory of Open Access Journals (Sweden)

Aviv Shachak

2011-06-01

Conclusion The proposed framework may be a useful tool for describing and characterising enduser support for HIT. it may also be used by decision makers and implementation leaders for planning purposes.

Robust Fully Distributed Minibatch Gradient Descent with Privacy Preservation

Directory of Open Access Journals (Sweden)

Gábor Danner

2018-01-01

Full Text Available Privacy and security are among the highest priorities in data mining approaches over data collected from mobile devices. Fully distributed machine learning is a promising direction in this context. However, it is a hard problem to design protocols that are efficient yet provide sufficient levels of privacy and security. In fully distributed environments, secure multiparty computation (MPC is often applied to solve these problems. However, in our dynamic and unreliable application domain, known MPC algorithms are not scalable or not robust enough. We propose a light-weight protocol to quickly and securely compute the sum query over a subset of participants assuming a semihonest adversary. During the computation the participants learn no individual values. We apply this protocol to efficiently calculate the sum of gradients as part of a fully distributed minibatch stochastic gradient descent algorithm. The protocol achieves scalability and robustness by exploiting the fact that in this application domain a “quick and dirty” sum computation is acceptable. We utilize the Paillier homomorphic cryptosystem as part of our solution combined with extreme lossy gradient compression to make the cost of the cryptographic algorithms affordable. We demonstrate both theoretically and experimentally, based on churn statistics from a real smartphone trace, that the protocol is indeed practically viable.

[Marxism as a theoretical and methodological framework in collective health: implications for systematic review and synthesis of evidence].

Science.gov (United States)

Soares, Cassia Baldini; Campos, Celia Maria Sivalli; Yonekura, Tatiana

2013-12-01

In this study, we discuss the integration in systematic reviews of research developed from a Marxist perspective of knowledge production and their results as evidence in healthcare. The study objectives are to review the assumptions of dialectical and historical materialism (DHM) and discuss the implications of dialectics for a literature review and the synthesis of evidence. DHM is a powerful framework for knowledge generation and transformation of policies and practices in healthcare. It assumes that social contradictions underlie the health-disease process, the fundamental theoretical construction in the field of collective health. Currently, we observe a considerable influence of the critical paradigm, of Marxist origin, in the construction of knowledge in health. Studies based on this critical paradigm incorporate complex methods, which are inherent to the guidelines of dialect, to identify the object and arrive at results that constitute evidence in healthcare. Systematic reviews should address the methodological difficulties associated with entirely integrating these results to healthcare.

Matching Adherence Interventions to Patient Determinants Using the Theoretical Domains Framework

NARCIS (Netherlands)

Allemann, S.S.; Nieuwlaat, R.; Bemt, B.J. van den; Hersberger, K.E.; Arnet, I.

2016-01-01

Introduction: Despite much research, interventions to improve medication adherence report disappointing and inconsistent results. Tailored approaches that match interventions and patient determinants of non-adherence were seldom used in clinical trials. The presence of a multitude of theoretical

A framework for evaluating the impact of obesity prevention strategies on socioeconomic inequalities in weight.

Science.gov (United States)

Backholer, Kathryn; Beauchamp, Alison; Ball, Kylie; Turrell, Gavin; Martin, Jane; Woods, Julie; Peeters, Anna

2014-10-01

We developed a theoretical framework to organize obesity prevention interventions by their likely impact on the socioeconomic gradient of weight. The degree to which an intervention involves individual agency versus structural change influences socioeconomic inequalities in weight. Agentic interventions, such as standalone social marketing, increase socioeconomic inequalities. Structural interventions, such as food procurement policies and restrictions on unhealthy foods in schools, show equal or greater benefit for lower socioeconomic groups. Many obesity prevention interventions belong to the agento-structural types of interventions, and account for the environment in which health behaviors occur, but they require a level of individual agency for behavioral change, including workplace design to encourage exercise and fiscal regulation of unhealthy foods or beverages. Obesity prevention interventions differ in their effectiveness across socioeconomic groups. Limiting further increases in socioeconomic inequalities in obesity requires implementation of structural interventions. Further empirical evaluation, especially of agento-structural type interventions, remains crucial.

Fluxon dynamics in long Josephson junctions in the presence of a temperature gradient or spatial nonuniformity

DEFF Research Database (Denmark)

Krasnov, V.M.; Oboznov, V.A.; Pedersen, Niels Falsig

1997-01-01

Fluxon dynamics in nonuniform Josephson junctions was studied both experimentally and theoretically. Two types of nonuniform junctions were considered: the first type had a nonuniform spatial distribution of critical and bias currents and the second had a temperature gradient applied along...... the junction. An analytical expression for the I-V curve in the presence of a temperature gradient or spatial nonuniformity was derived. It was shown that there is no static thermomagnetic Nernst effect due to Josephson fluxon motion despite the existence of a force pushing fluxons in the direction of smaller...

Experimental and numerical analysis of sodium-carbonate salt gradient solar-pond performance under simulated solar-radiation

Energy Technology Data Exchange (ETDEWEB)

Kurt, Hueseyin; Ozkaymak, Mehmet [Zonguldak Karaelmas University, Technical Education Faculty, 78200 Karabuk (Turkey); Binark, A. Korhan [Marmara University, Technical Education Faculty, 34722 Kuyubasi-Istanbul (Turkey)

2006-04-01

The objective of this study is to investigate experimentally and theoretically whether sodium carbonate (Na{sub 2}CO{sub 3}) salt is suitable for establishing a salinity gradient in a salt-gradient solar-pond (SGSP). For this purpose, a small-scale prismatic solar-pond was constructed. Experiments were conducted in the laboratory under the incident radiation from two halogen-lamps acting as a solar simulator. Furthermore, a one-dimensional transient mathematical model that describes the heat and mass transfer behaviour of the SGSP was developed. The differential equations obtained were solved numerically using a finite-difference method. It was found from the experiments that the density gradient, achieved using sodium carbonate salt, can suppress convection from the bottom to the surface of the pond. (author)

Experimental and numerical analysis of sodium-carbonate salt gradient solar-pond performance under simulated solar-radiation

International Nuclear Information System (INIS)

Kurt, Hueseyin; Ozkaymak, Mehmet; Binark, A. Korhan

2006-01-01

The objective of this study is to investigate experimentally and theoretically whether sodium carbonate (Na 2 CO 3 ) salt is suitable for establishing a salinity gradient in a salt-gradient solar-pond (SGSP). For this purpose, a small-scale prismatic solar-pond was constructed. Experiments were conducted in the laboratory under the incident radiation from two halogen-lamps acting as a solar simulator. Furthermore, a one-dimensional transient mathematical model that describes the heat and mass transfer behaviour of the SGSP was developed. The differential equations obtained were solved numerically using a finite-difference method. It was found from the experiments that the density gradient, achieved using sodium carbonate salt, can suppress convection from the bottom to the surface of the pond

CERN/KEK: Very high accelerating gradients

Energy Technology Data Exchange (ETDEWEB)

Anon.

1993-01-15

Full text: A world-wide effort is under way to develop linear electron-positron colliders so that physics experiments can be extended into a range of energies where circular machines (necessarily much larger than CERN's 27-kilometre LEP machine) would be crippled by synchrotron radiation. CERN is studying the feasibility of building a 2 TeV machine called CLIC powered not by individual klystrons, but by a high intensity electron 'drive' linac running parallel to the main linac (November 1990, page 7). This drive linac will itself be powered by similar superconducting cavities to those developed for LEP. A high gradient is an obvious design aim for any future high energy linear collider because it makes it shorter and therefore cheaper - the design figure for the CLIC machine is 80 MV/m. The CLIC study group has taken a significant step forward in demonstrating the technical feasibility of their machine by achieving peak and average accelerating gradients of 137 MV/m and 84 MV/m respectively in a short section of accelerating structure during high gradient tests at the Japanese KEK Laboratory last year. This result obtained within the framework of a CERN/KEK collaboration on linear colliders was obtained using a 20-cell accelerating section built at CERN using state-of the- art technology which served both as a model for CLIC studies as well as a prototype for the Japanese Linear Collider studies. The operating frequency of the model accelerating section is 2.6 times lower than the CLIC frequency but was chosen because a high power r.f. source and pulse compression scheme has been developed for this frequency at KEK. Testing CLIC models at 11.4 GHz is however more stringent than at 30 GHz because the chance of electrical breakdown increases as the frequency is lowered. This recent result clearly demonstrates that a gradient of 80 MV/m is feasible.

CERN/KEK: Very high accelerating gradients

International Nuclear Information System (INIS)

Anon.

1993-01-01

Full text: A world-wide effort is under way to develop linear electron-positron colliders so that physics experiments can be extended into a range of energies where circular machines (necessarily much larger than CERN's 27-kilometre LEP machine) would be crippled by synchrotron radiation. CERN is studying the feasibility of building a 2 TeV machine called CLIC powered not by individual klystrons, but by a high intensity electron 'drive' linac running parallel to the main linac (November 1990, page 7). This drive linac will itself be powered by similar superconducting cavities to those developed for LEP. A high gradient is an obvious design aim for any future high energy linear collider because it makes it shorter and therefore cheaper - the design figure for the CLIC machine is 80 MV/m. The CLIC study group has taken a significant step forward in demonstrating the technical feasibility of their machine by achieving peak and average accelerating gradients of 137 MV/m and 84 MV/m respectively in a short section of accelerating structure during high gradient tests at the Japanese KEK Laboratory last year. This result obtained within the framework of a CERN/KEK collaboration on linear colliders was obtained using a 20-cell accelerating section built at CERN using state-of the- art technology which served both as a model for CLIC studies as well as a prototype for the Japanese Linear Collider studies. The operating frequency of the model accelerating section is 2.6 times lower than the CLIC frequency but was chosen because a high power r.f. source and pulse compression scheme has been developed for this frequency at KEK. Testing CLIC models at 11.4 GHz is however more stringent than at 30 GHz because the chance of electrical breakdown increases as the frequency is lowered. This recent result clearly demonstrates that a gradient of 80 MV/m is feasible

Exploring 3D non-interpenetrated metal-organic framework with malonate-bridged Co(II) coordination polymer: structural elucidation and theoretical study

Science.gov (United States)

Hossain, Anowar; Mandal, Tripti; Mitra, Monojit; Manna, Prankrishna; Bauzá, Antonio; Frontera, Antonio; Seth, Saikat Kumar; Mukhopadhyay, Subrata

2017-12-01

A Co(II)-based coordination polymer with tetranuclear cobalt(II)-malonate cluster has been easily generated by aqueous medium self-assembly from Cobalt(II) chloride hexahydrate and malonic acid. The structure exhibits a non-interpenetrating, highly undulating two-dimensional (2D) bi-layer network with (4,4) topology. The crystal structure is composed of infinite interdigitated 2D metal-organic bi-layers which extended to an intricate 3D framework through the interbilayer hydrogen bonds. We have studied energetically by means of Density Functional Theory (DFT) calculations the H-bonding interactions that connect the 2D metal-organic bi-layers. The finite theoretical models have been used to compute conventional O‒H•••O and unconventional C‒H•••O interactions which plays a key role to build 3D architecture.

Fractional-order gradient descent learning of BP neural networks with Caputo derivative.

Science.gov (United States)

Wang, Jian; Wen, Yanqing; Gou, Yida; Ye, Zhenyun; Chen, Hua

2017-05-01

Fractional calculus has been found to be a promising area of research for information processing and modeling of some physical systems. In this paper, we propose a fractional gradient descent method for the backpropagation (BP) training of neural networks. In particular, the Caputo derivative is employed to evaluate the fractional-order gradient of the error defined as the traditional quadratic energy function. The monotonicity and weak (strong) convergence of the proposed approach are proved in detail. Two simulations have been implemented to illustrate the performance of presented fractional-order BP algorithm on three small datasets and one large dataset. The numerical simulations effectively verify the theoretical observations of this paper as well. Copyright © 2017 Elsevier Ltd. All rights reserved.

Rank gradient and p-gradient of amalgamated free products and HNN extensions

OpenAIRE

Pappas, Nathaniel

2013-01-01

We calculate the rank gradient and p-gradient of free products, free products with amalgamation over an amenable subgroup, and HNN extensions with an amenable associated subgroup. The notion of cost is used to compute the rank gradient of amalgamated free products and HNN extensions. For the p-gradient the Kurosh subgroup theorems for amalgamated free products and HNN extensions will be used.

Testing the Consolidated Framework for Implementation Research on health care innovations from South Yorkshire.

Science.gov (United States)

Ilott, Irene; Gerrish, Kate; Booth, Andrew; Field, Becky

2013-10-01

There is an international imperative to implement research into clinical practice to improve health care. Understanding the dynamics of change requires knowledge from theoretical and empirical studies. This paper presents a novel approach to testing a new meta theoretical framework: the Consolidated Framework for Implementation Research. The utility of the Framework was evaluated using a post hoc, deductive analysis of 11 narrative accounts of innovation in health care services and practice from England, collected in 2010. A matrix, comprising the five domains and 39 constructs of the Framework was developed to examine the coherence of the terminology, to compare results across contexts and to identify new theoretical developments. The Framework captured the complexity of implementation across 11 diverse examples, offering theoretically informed, comprehensive coverage. The Framework drew attention to relevant points in individual cases together with patterns across cases; for example, all were internally developed innovations that brought direct or indirect patient advantage. In 10 cases, the change was led by clinicians. Most initiatives had been maintained for several years and there was evidence of spread in six examples. Areas for further development within the Framework include sustainability and patient/public engagement in implementation. Our analysis suggests that this conceptual framework has the potential to offer useful insights, whether as part of a situational analysis or by developing context-specific propositions for hypothesis testing. Such studies are vital now that innovation is being promoted as core business for health care. © 2012 John Wiley & Sons Ltd.

Optimal Weighting of Multi-Spacecraft Data to Estimate Gradients of Physical Fields

Science.gov (United States)

Chanteur, G. M.; Le Contel, O.; Sahraoui, F.; Retino, A.; Mirioni, L.

2016-12-01

Multi-spacecraft missions like the ESA mission CLUSTER and the NASA mission MMS are essential to improve our understanding of physical processes in space plasmas. Several methods were designed in the 90's during the preparation phase of the CLUSTER mission to estimate gradients of physical fields from simultaneous multi-points measurements [1, 2]. Both CLUSTER and MMS involve four spacecraft with identical full scientific payloads including various sensors of electromagnetic fields and different type of particle detectors. In the standard methods described in [1, 2], which are presently in use, data from the four spacecraft have identical weights and the estimated gradients are most reliable when the tetrahedron formed by the four spacecraft is regular. There are three types of errors affecting the estimated gradients (see chapter 14 in [1]) : i) truncature errors are due to local non-linearity of spatial variations, ii) physical errors are due to instruments, and iii) geometrical errors are due to uncertainties on the positions of the spacecraft. An assessment of truncature errors for a given observation requires a theoretical model of the measured field. Instrumental errors can easily be taken into account for a given geometry of the cluster but are usually less than the geometrical errors which diverge quite fast when the tetrahedron flattens, a circumstance occurring twice per orbit of the cluster. Hence reliable gradients can be estimated only on part of the orbit. Reciprocal vectors of the tetrahedron were presented in chapter 4 of [1], they have the advantage over other methods to treat the four spacecraft symmetrically and to allow a theoretical analysis of the errors (see chapters 4 of [1] and 4 of [2]). We will present Generalized Reciprocal Vectors for weighted data and an optimization procedure to improve the reliability of the estimated gradients when the tetrahedron is not regular. A brief example using CLUSTER or MMS data will be given. This approach

A cooperative game-theoretic framework for negotiating marine spatial allocation agreements among heterogeneous players.

Science.gov (United States)

Kyriazi, Zacharoula; Lejano, Raul; Maes, Frank; Degraer, Steven

2017-02-01

Marine spatial allocation has become, in recent decades, a political flashpoint, fuelled by political power struggles, as well as the continuously increasing demand for marine space by both traditional and emerging marine uses. To effectively address this issue, we develop a decision-making procedure, that facilitates the distribution of disputed areas of specific size among heterogeneous players in a transparent and ethical way, while considering coalitional formations through coexistence. To do this, we model players' alternative strategies and payoffs within a cooperative game-theoretic framework. Depending on whether transferable utility (TU) or non-transferable utility (NTU) is the more appropriate assumption, we illustrate the use of the TU Shapley value and the Lejano's fixed point NTU Shapley value to solve for the ideal allocations. The applicability and effectiveness of the process has been tested in a case study area, the Dogger Bank Special Area of Conservation in the North Sea, which involves three totally or partially conflicting activities, i.e. fishing, nature conservation and wind farm development. The findings demonstrate that the process is capable of providing a unique, fair and equitable division of space Finally, among the two solution concepts proposed the fixed point NTU Shapley value manages to better address the heterogeneity of the players and thus to provide a more socially acceptable allocation that favours the weaker player, while demonstrating the importance of the monetary valuation attributed by each use to the area. Copyright © 2016 Elsevier Ltd. All rights reserved.

N-barN interaction theoretical models

International Nuclear Information System (INIS)

Loiseau, B.

1991-12-01

In the framework of antinucleon-nucleon interaction theoretical models, our present understanding on the N-barN interaction is discussed, either from quark- or/and meson- and baryon-degrees of freedom, by considering the N-barN annihilation into mesons and the N-barN elastic and charge-exchange scattering. (author) 52 refs., 11 figs., 2 tabs

A strain gradient plasticity theory with application to wire torsion

KAUST Repository

Liu, J. X.

2014-06-05

Based on the framework of the existing strain gradient plasticity theories, we have examined three kinds of relations for the plastic strain dependence of the material intrinsic length scale, and thus developed updated strain gradient plasticity versions with deformation-dependent characteristic length scales. Wire torsion test is taken as an example to assess existing and newly built constitutive equations. For torsion tests, with increasing plastic strain, a constant intrinsic length predicts too high a torque, while a decreasing intrinsic length scale can produce better predictions instead of the increasing one, different from some published observations. If the Taylor dislocation rule is written in the Nix-Gao form, the derived constitutive equations become singular when the hardening exponent gets close to zero, which seems questionable and calls for further experimental clarifications on the exact coupling of hardening due to statistically stored dislocations and geometrically necessary dislocations. Particularly, when comparing the present model with the mechanism-based strain gradient plasticity, the present model satisfies the reciprocity relation naturally and gives different predictions even under the same parameter setting. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Contextualising Vocational Knowledge : A Theoretical Framework and Illustrations From Culinary Education

NARCIS (Netherlands)

Heusdens, Wenja; Bakker, Arthur|info:eu-repo/dai/nl/272605778; Baartman, L.K.J.|info:eu-repo/dai/nl/261829580; de Bruijn, Elly|info:eu-repo/dai/nl/074460919

2016-01-01

The nature of knowledge in vocational education is often described in dichotomies such as theory versus practice or general versus specific. Although different scholars now acknowledge that vocational knowledge is more than putting bits of theoretical and practical knowledge together, it is still

A Framework for Hierarchical Perception-Action Learning Utilizing Fuzzy Reasoning.