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

ERIC Educational Resources Information Center

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…

Functions of social support and self-verification in association with loneliness, depression, and stress.

PubMed

Wright, Kevin B; King, Shawn; Rosenberg, Jenny

2014-01-01

This study investigated the influence of social support and self-verification on loneliness, depression, and stress among 477 college students. The authors propose and test a theoretical model using structural equation modeling. The results indicated empirical support for the model, with self-verification mediating the relation between social support and health outcomes. The results have implications for social support and self-verification research, which are discussed along with directions for future research and limitations of the study.

SN1987A: The Birth of a Supernova Remnant

NASA Technical Reports Server (NTRS)

McCray, Richard

2003-01-01

This grant was intended to support the development of theoretical models needed to interpret and understand the observations by the Hubble Space Telescope and the Chandra X-ray telescope of the rapidly developing remnant of Supernova 1987A. In addition, we carried out a few investigations of related topics. The project was spectacularly successful. The models that we developed provide the definitive framework for predicting and interpreting this phenomenon. Following is a list of publications based on our work. Some of these papers include results of both theoretical modeling supported by this project and also analysis of data supported by the Space Telescope Science Institute and the Chandra X-ray Observatory. We first list papers published in refereed journals, then conference proceedings and book chapters, and also an educational web site.

Patient perceptions of patient-centred care: empirical test of a theoretical model.

PubMed

Rathert, Cheryl; Williams, Eric S; McCaughey, Deirdre; Ishqaidef, Ghadir

2015-04-01

Patient perception measures are gaining increasing interest among scholars and practitioners. The aim of this study was to empirically examine a conceptual model of patient-centred care using patient perception survey data. Patient-centred care is one of the Institute of Medicine's objectives for improving health care in the 21st century. Patient interviews conducted by the Picker Institute/Commonwealth Fund in the 1980s resulted in a theoretical model and survey questions with dimensions and attributes patients defined as patient-centered. The present study used survey data from patients with overnight visits at 142 U.S. hospitals. Regression analysis found significant support for the theoretical model. Perceptions of emotional support had the strongest relationship with overall care ratings. Coordination of care, and physical comfort were strongly related as well. Understanding how patients experience their care can help improve understanding of what patients believe is patient-centred, and of how care processes relate to important patient outcomes. © 2012 John Wiley & Sons Ltd.

A theoretical approach to artificial intelligence systems in medicine.

PubMed

Spyropoulos, B; Papagounos, G

1995-10-01

The various theoretical models of disease, the nosology which is accepted by the medical community and the prevalent logic of diagnosis determine both the medical approach as well as the development of the relevant technology including the structure and function of the A.I. systems involved. A.I. systems in medicine, in addition to the specific parameters which enable them to reach a diagnostic and/or therapeutic proposal, entail implicitly theoretical assumptions and socio-cultural attitudes which prejudice the orientation and the final outcome of the procedure. The various models -causal, probabilistic, case-based etc. -are critically examined and their ethical and methodological limitations are brought to light. The lack of a self-consistent theoretical framework in medicine, the multi-faceted character of the human organism as well as the non-explicit nature of the theoretical assumptions involved in A.I. systems restrict them to the role of decision supporting "instruments" rather than regarding them as decision making "devices". This supporting role and, especially, the important function which A.I. systems should have in the structure, the methods and the content of medical education underscore the need of further research in the theoretical aspects and the actual development of such systems.

Multiple Pathways from Stress to Suicidality and the Protective Effect of Social Support in Hong Kong Adolescents

ERIC Educational Resources Information Center

Cheng, Sheung-Tak; Chan, Alfred C. M.

2007-01-01

Two theoretical models were constructed to illustrate how stressful events, family and friends support, depression, substance use, and death attitude mutually influence to create cumulative risks for suicide. The models were evaluated using structural equation modeling. Results showed that suicidality was strongly predicted by death attitude,…

Diffusion of Web Supported Instruction in Higher Education--The Case of Tel-Aviv University

ERIC Educational Resources Information Center

Soffer, Tal; Nachmias, Rafi; Ram, Judith

2010-01-01

This paper describes a study that focused on long-term web-supported learning diffusion among lecturers at Tel Aviv University (TAU), from an organizational point of view. The theoretical models we used to examine this process are Rogers' model for "Diffusion of Innovation" (1995) and Bass's "Diffusion Model" (1969). The study…

A theoretical model of co-worker responses to work reintegration processes.

PubMed

Dunstan, Debra A; Maceachen, Ellen

2014-06-01

Emerging research has shown that co-workers have a significant influence on the return-to-work outcomes of partially fit ill or injured employees. By drawing on theoretical findings from the human resource and wider behavioral sciences literatures, our goal was to formulate a theoretical model of the influences on and outcomes of co-worker responses within work reintegration. From a search of 15 data bases covering the social sciences, business and medicine, we identified articles containing models of the factors that influence co-workers' responses to disability accommodations; and, the nature and impact of co-workers' behaviors on employee outcomes. To meet our goal, we combined identified models to form a comprehensive model of the relevant factors and relationships. Internal consistency and externally validity were assessed. The combined model illustrates four key findings: (1) co-workers' behaviors towards an accommodated employee are influenced by attributes of that employee, the illness or injury, the co-worker themselves, and the work environment; (2) the influences-behaviour relationship is mediated by perceptions of the fairness of the accommodation; (3) co-workers' behaviors affect all work reintegration outcomes; and (4) co-workers' behaviours can vary from support to antagonism and are moderated by type of support required, the social intensity of the job, and the level of antagonism. Theoretical models from the wider literature are useful for understanding the impact of co-workers on the work reintegration process. To achieve optimal outcomes, co-workers need to perceive the arrangements as fair. Perceptions of fairness might be supported by co-workers' collaborative engagement in the planning, monitoring and review of work reintegration activities.

Shifting attention from objective risk factors to patients' self-assessed health resources: a clinical model for general practice.

PubMed

Hollnagel, H; Malterud, K

1995-12-01

The study was designed to present and apply theoretical and empirical knowledge for the construction of a clinical model intended to shift the attention of the general practitioner from objective risk factors to self-assessed health resources in male and female patients. Review, discussion and analysis of selected theoretical models about personal health resources involving assessing existing theories according to their emphasis concerning self-assessed vs. doctor-assessed health resources, specific health resources vs. life and coping in general, abstract vs. clinically applicable theory, gender perspective explicitly included or not. Relevant theoretical models on health and coping (salutogenesis, coping and social support, control/demand, locus of control, health belief model, quality of life), and the perspective of the underprivileged Other (critical theory, feminist standpoint theory, the patient-centred clinical method) were presented and assessed. Components from Antonovsky's salutogenetic perspective and McWhinney's patient-centred clinical method, supported by gender perspectives, were integrated to a clinical model which is presented. General practitioners are recommended to shift their attention from objective risk factors to self-assessed health resources by means of the clinical model. The relevance and feasibility of the model should be explored in empirical research.

Modelling public support for wildland fire policy

Treesearch

J.D. Absher; J.J. Vaske

2007-01-01

Theoretically grounded explanations of wildland fire policy can be improved by empirically documenting the causal influences of support for (or opposition to) management alternatives. This chapter proposes a model based on the specificity principle (i.e. correspondence between measured variables to empirically examine four common wildland fire policies in relation to...

The motion of bubbles inside drops in containerless processing

NASA Technical Reports Server (NTRS)

Shankar, N.; Annamalai, P.; Cole, R.; Subramanian, R. S.

1982-01-01

A theoretical model of thermocapillary bubble motion inside a drop, located in a space laboratory, due to an arbitrary axisymmetric temperature distribution on the drop surface was constructed. Typical results for the stream function and temperature fields as well as the migration velocity of the bubble were obtained in the quasistatic limit. The motion of bubbles in a rotating body of liquid was studied experimentally, and an approximate theoretical model was developed. Comparison of the experimental observations of the bubble trajectories and centering times with theoretical predictions lends qualified support to the theory.

Watershed Management Optimization Support Tool (WMOST) v3: Theoretical Documentation

EPA Science Inventory

The Watershed Management Optimization Support Tool (WMOST) is a decision support tool that facilitates integrated water management at the local or small watershed scale. WMOST models the environmental effects and costs of management decisions in a watershed context, accounting fo...

Watershed Management Optimization Support Tool (WMOST) v2: Theoretical Documentation

EPA Science Inventory

The Watershed Management Optimization Support Tool (WMOST) is a decision support tool that evaluates the relative cost-effectiveness of management practices at the local or watershed scale. WMOST models the environmental effects and costs of management decisions in a watershed c...

[Facing the difficult experience even with support: the underage adolescent experiencing motherhood].

PubMed

Andrade, Paula Rosenberg de; Ohara, Conceição Vieira da Silva; Borba, Regina Issuzu Hirooka de; Ribeiro, Circéa Amalia

2015-01-01

To understand the meaning of childcare for the underage adolescent mother, to reveal the demands of care and to build a theoretical model based on this experience. Qualitative research with symbolic interactionism as the theoretical framework and the grounded theory as the methodological framework; nine adolescents participated in the study. The semi-structured interview was used to collect data from September 2008 to September 2011, during paediatric nursing consultation at the Centro Assistencial Cruz de Malta, a philanthropic institution in the city of São Paulo/Brazil. Data analysis led to the construction of the theoretical model,Facing a difficult experience even with support. The experience shows that the difficulties to care for a child, even with help, are not met, only mitigated, and that underage adolescents do not have the maturity to cope with this experience.

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

PubMed

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.

Transmembrane protein diffusion in gel-supported dual-leaflet membranes.

PubMed

Wang, Chih-Ying; Hill, Reghan J

2014-11-18

Tools to measure transmembrane-protein diffusion in lipid bilayer membranes have advanced in recent decades, providing a need for predictive theoretical models that account for interleaflet leaflet friction on tracer mobility. Here we address the fully three-dimensional flows driven by a (nonprotruding) transmembrane protein embedded in a dual-leaflet membrane that is supported above and below by soft porous supports (e.g., hydrogel or extracellular matrix), each of which has a prescribed permeability and solvent viscosity. For asymmetric configurations, i.e., supports with contrasting permeability, as realized for cells in contact with hydrogel scaffolds or culture media, the diffusion coefficient can reflect interleaflet friction. Reasonable approximations, for sufficiently large tracers on low-permeability supports, are furnished by a recent phenomenological theory from the literature. Interpreting literature data, albeit for hard-supported membranes, provides a theoretical basis for the phenomenological Stokes drag law as well as strengthening assertions that nonhydrodynamic interactions are important in supported bilayer systems, possibly leading to overestimates of the membrane/leaflet viscosity. Our theory provides a theoretical foundation for future experimental studies of tracer diffusion in gel-supported membranes.

High Energy Theory Workshops and Visitors at the Michigan Center for Theoretical Physics FY16

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

Pierce, Aaron

This award provided partial support for the Michigan Center for Theoretical Physics to host two workshops "Beyond the Standard Model 2016" in October 2016, and the "5th MCTP Symposium: Foundations of String Cosmology" in April 2017 on the University of Michigan campus.

The Needs-Based Assessment of Parental (Guardian) Support: a test of its validity and reliability.

PubMed

Bolen, Rebecca M; Leah Lamb, J; Gradante, Jennifer

2002-10-01

The purpose of this paper is to present a newly developed measure of guardian support, the Needs-Based Assessment of Parental (Guardian) Support (NAPS), an empirical evaluation of that measure, and its comparison with another measure of guardian support. The theoretical model that underlies this measure applies humanistic theory and Maslow's hierarchy of needs to the understanding of guardian support. The study employed a cross-sectional nonexperimental survey design using 183 nonoffending guardians who accompanied children presenting for a medical/forensic examination for sexual abuse. The NAPS and an existing measure of guardian support were administered during the hospital outpatient visit, and basic information concerning the child and abuse situations were gathered. The NAPS had robust psychometric properties and was culturally sensitive. Tests of specific hypotheses supported the construct validity of the measure and a conceptualization of guardian support as hierarchical, with four stages of support. The brevity and ease of administration of the NAPS for both the clinician and guardian suggest that it is a viable assessment tool. The strong support for the NAPS' underlying theoretical model suggests that the nonoffending guardians' available resources need to be considered when assessing guardian support.

Open access support groups for people experiencing personality disorders: do group members' experiences reflect the theoretical foundations of the SUN project?

PubMed

Gillard, Steve; White, Rachel; Miller, Steve; Turner, Kati

2015-03-01

The SUN Project is an innovative, open access support group, based in the community, for people experiencing personality disorders, developed in response to UK Department of Health policy advocating improvements in personality disorders services. The aim of this article is to critically explore where and how the theoretically informed model underpinning the SUN Project is reflected in the view and experiences of people attending the project. This article reports an in-depth, qualitative interview-based study employing a critical realist approach. As part of a larger study about self-care and mental health, in-depth qualitative interviews were held with 38 people new to the SUN Project, and again 9 months later. Data were extracted that were relevant to core components of the project model and were subjected to thematic analysis. The critical realist approach was used to move back and forth between empirical data and theory underpinning the SUN project, providing critical insight into the model. Participant accounts were broadly concordant with core components of the SUN Project's underlying model: Open access and self-referral; group therapeutic processes; community-based support; service users as staff. There were some tensions between interviewee accounts and theoretical aspects of the model, notably around the challenges that group processes presented for some individuals. The model underlying the SUN Project is useful in informing good practice in therapeutic, community-based peer support groups for people experiencing personality disorders. Careful consideration should be given to a limited multi-modal approach, providing focused one-to-one support for vulnerable individuals who find it hard to engage in group processes. Facilitated peer support groups based in the community may act as a powerful therapeutic resource for people experiencing personality disorders. Promoting open access and self-referral to support groups may increase feelings of empowerment and engagement for people experiencing personality disorders. Some individuals experiencing personality disorders who could potentially benefit from therapeutic groups may need focused one-to-one support to do so. © 2014 The British Psychological Society.

Psychological and Pedagogic Support of Children with Health Limitations

ERIC Educational Resources Information Center

Ezhovkina, Elena Vasilyevna; Ryabova, Natalia Vladimirovna

2015-01-01

The article represented theoretic analysis of the literature on the problem of psychological and pedagogic support of disabled children. It defined the following terms: a successfully adapting disabled child, a model, interaction of specialists, psychological and pedagogic support. The article also determined the key components of a successfully…

Application of the Consumer Decision-Making Model to Hearing Aid Adoption in First-Time Users

PubMed Central

Amlani, Amyn M.

2016-01-01

Since 1980, hearing aid adoption rates have remained essentially the same, increasing at a rate equal to the organic growth of the population. Researchers have used theoretical models from psychology and sociology to determine those factors or constructs that lead to the adoption of hearing aids by first-time impaired listeners entering the market. In this article, a theoretical model, the Consumer Decision-Making Model (CDM), premised on the neobehavioral approach that considers an individual's psychological and cognitive emphasis toward a product or service, is described. Three theoretical models (i.e., transtheoretical, social model of disability, Health Belief Model), and their relevant findings to the hearing aid market, are initially described. The CDM is then presented, along with supporting evidence of the model's various factors from the hearing aid literature. Future applications of the CDM to hearing health care also are discussed. PMID:27516718

Application of the Consumer Decision-Making Model to Hearing Aid Adoption in First-Time Users.

PubMed

Amlani, Amyn M

2016-05-01

Since 1980, hearing aid adoption rates have remained essentially the same, increasing at a rate equal to the organic growth of the population. Researchers have used theoretical models from psychology and sociology to determine those factors or constructs that lead to the adoption of hearing aids by first-time impaired listeners entering the market. In this article, a theoretical model, the Consumer Decision-Making Model (CDM), premised on the neobehavioral approach that considers an individual's psychological and cognitive emphasis toward a product or service, is described. Three theoretical models (i.e., transtheoretical, social model of disability, Health Belief Model), and their relevant findings to the hearing aid market, are initially described. The CDM is then presented, along with supporting evidence of the model's various factors from the hearing aid literature. Future applications of the CDM to hearing health care also are discussed.

Developing a change model for peer worker interventions in mental health services: a qualitative research study.

PubMed

Gillard, S; Gibson, S L; Holley, J; Lucock, M

2015-10-01

A range of peer worker roles are being introduced into mental health services internationally. There is some evidence that attests to the benefits of peer workers for the people they support but formal trial evidence in inconclusive, in part because the change model underpinning peer support-based interventions is underdeveloped. Complex intervention evaluation guidance suggests that understandings of how an intervention is associated with change in outcomes should be modelled, theoretically and empirically, before the intervention can be robustly evaluated. This paper aims to model the change mechanisms underlying peer worker interventions. In a qualitative, comparative case study of ten peer worker initiatives in statutory and voluntary sector mental health services in England in-depth interviews were carried out with 71 peer workers, service users, staff and managers, exploring their experiences of peer working. Using a Grounded Theory approach we identified core processes within the peer worker role that were productive of change for service users supported by peer workers. Key change mechanisms were: (i) building trusting relationships based on shared lived experience; (ii) role-modelling individual recovery and living well with mental health problems; (iii) engaging service users with mental health services and the community. Mechanisms could be further explained by theoretical literature on role-modelling and relationship in mental health services. We were able to model process and downstream outcomes potentially associated with peer worker interventions. An empirically and theoretically grounded change model can be articulated that usefully informs the development, evaluation and planning of peer worker interventions.

On the potential for using immersive virtual environments to support laboratory experiment contextualisation

NASA Astrophysics Data System (ADS)

Machet, Tania; Lowe, David; Gütl, Christian

2012-12-01

This paper explores the hypothesis that embedding a laboratory activity into a virtual environment can provide a richer experimental context and hence improve the understanding of the relationship between a theoretical model and the real world, particularly in terms of the model's strengths and weaknesses. While an identified learning objective of laboratories is to support the understanding of the relationship between models and reality, the paper illustrates that this understanding is hindered by inherently limited experiments and that there is scope for improvement. Despite the contextualisation of learning activities having been shown to support learning objectives in many fields, there is traditionally little contextual information presented during laboratory experimentation. The paper argues that the enhancing laboratory activity with contextual information affords an opportunity to improve students' understanding of the relationship between the theoretical model and the experiment (which is effectively a proxy for the complex real world), thereby improving their understanding of the relationship between the model and reality. The authors propose that these improvements can be achieved by setting remote laboratories within context-rich virtual worlds.

Correlates of emotional congruence with children in sexual offenders against children: a test of theoretical models in an incarcerated sample.

PubMed

McPhail, Ian V; Hermann, Chantal A; Fernandez, Yolanda M

2014-02-01

Emotional congruence with children is a psychological construct theoretically involved in the etiology and maintenance of sexual offending against children. Research conducted to date has not examined the relationship between emotional congruence with children and other psychological meaningful risk factors for sexual offending against children. The current study derived potential correlates of emotional congruence with children from the published literature and proposed three models of emotional congruence with children that contain relatively unique sets of correlates: the blockage, sexual deviance, and psychological immaturity models. Using Area under the Curve analysis, we assessed the relationship between emotional congruence with children and offense characteristics, victim demographics, and psychologically meaningful risk factors in a sample of incarcerated sexual offenders against children (n=221). The sexual deviance model received the most support: emotional congruence with children was significantly associated with deviant sexual interests, sexual self-regulation problems, and cognition that condones and supports child molestation. The blockage model received partial support, and the immaturity model received the least support. Based on the results, we propose a set of further predictions regarding the relationships between emotional congruence with children and other psychologically meaningful risk factors to be examined in future research. Copyright © 2013 Elsevier Ltd. All rights reserved.

Neonatal physical therapy. Part II: Practice frameworks and evidence-based practice guidelines.

PubMed

Sweeney, Jane K; Heriza, Carolyn B; Blanchard, Yvette; Dusing, Stacey C

2010-01-01

(1) To outline frameworks for neonatal physical therapy based on 3 theoretical models, (2) to describe emerging literature supporting neonatal physical therapy practice, and (3) to identify evidence-based practice recommendations. Three models are presented as a framework for neonatal practice: (1) dynamic systems theory including synactive theory and the theory of neuronal group selection, (2) the International Classification of Functioning, Disability and Health, and (3) family-centered care. Literature is summarized to support neonatal physical therapists in the areas of examination, developmental care, intervention, and parent education. Practice recommendations are offered with levels of evidence identified. Neonatal physical therapy practice has a theoretical and evidence-based structure, and evidence is emerging for selected clinical procedures. Continued research to expand the science of neonatal physical therapy is critical to elevate the evidence and support practice recommendations.

Development of Support Service for Prevention and Recovery from Dementia and Science of Lethe

NASA Astrophysics Data System (ADS)

Otake, Mihoko

Purpose of this study is to explore service design method through the development of support service for prevention and recovery from dementia towards science of lethe. We designed and implemented conversation support service via coimagination method based on multiscale service design method, both were proposed by the author. Multiscale service model consists of tool, event, human, network, style and rule. Service elements at different scales are developed according to the model. Interactive conversation supported by coimagination method activates cognitive functions so as to prevent progress of dementia. This paper proposes theoretical bases for science of lethe. Firstly, relationship among coimagination method and three cognitive functions including division of attention, planning, episodic memory which decline at mild cognitive imparement. Secondly, thought state transition model during conversation which describes cognitive enhancement via interactive communication. Thirdly, Set Theoretical Measure of Interaction is proposed for evaluating effectiveness of conversation to cognitive enhancement. Simulation result suggests that the ideas which cannot be explored by each speaker are explored during interactive conversation. Finally, coimagination method compared with reminiscence therapy and its possibility for collaboration is discussed.

A New Model that Generates Lotka's Law.

ERIC Educational Resources Information Center

Huber, John C.

2002-01-01

Develops a new model for a process that generates Lotka's Law. Topics include measuring scientific productivity through the number of publications; rate of production; career duration; randomness; Poisson distribution; computer simulations; goodness-of-fit; theoretical support for the model; and future research. (Author/LRW)

Family-Supportive Organization Perceptions, Multiple Dimensions of Work-Family Conflict, and Employee Satisfaction: A Test of Model across Five Samples

ERIC Educational Resources Information Center

Lapierre, Laurent M.; Spector, Paul E.; Allen, Tammy D.; Poelmans, Steven; Cooper, Cary L.; O'Driscoll, Michael P.; Sanchez, Juan I.; Brough, Paula; Kinnunen, Ulla

2008-01-01

Using samples of managers drawn from five Western countries, we tested a theoretical model linking employees' perceptions of their work environment's family-supportiveness to six different dimensions of work-family conflict (WFC), and to their job satisfaction, family satisfaction, and life satisfaction. Our results are consistent with a causal…

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

PubMed

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.

Hospital nurses' wellbeing at work: a theoretical model.

PubMed

Utriainen, Kati; Ala-Mursula, Leena; Kyngäs, Helvi

2015-09-01

To develop a theoretical model of hospital nurses' wellbeing at work. The concept of wellbeing at work is presented without an exact definition and without considering different contents. A model was developed in a deductive manner and empirical data collected from nurses (n = 233) working in a university hospital. Explorative factor analysis was used. The main concepts were: patients' experience of high-quality care; assistance and support among nurses; nurses' togetherness and cooperation; fluent practical organisation of work; challenging and meaningful work; freedom to express diverse feelings in the work community; well-conducted everyday nursing; status related to the work itself; fair and supportive leadership; opportunities for professional development; fluent communication with other professionals; and being together with other nurses in an informal way. Themes included: collegial relationships; enhancing high-quality patient care; supportive and fair leadership; challenging, meaningful and well organised work; and opportunities for professional development. Object-dependent wellbeing was supported. Managers should focus on strengthening the positive aspect of wellbeing at work, focusing on providing fluently organised work practices, fair and supportive leadership and togetherness while allowing nurses to implement their own ideas and promote the experience of meaningfulness. © 2014 John Wiley & Sons Ltd.

Received and perceived social support in times of stress: a test of the social support deterioration deterrence model.

PubMed

Norris, F H; Kaniasty, K

1996-09-01

The authors evaluated the impact of receiving social support on subsequent levels of perceived social support and psychological distress in 2 independent samples of victims of severe natural disasters: Hurricane Hugo (n = 498) and Hurricane Andrew (n = 404). A social support deterioration deterrence model was proposed that stipulated that postdisaster mobilization of received support counteracts the deterioration in expectations of support often experienced by victims of major life events. LISREL analyses of data collected 12 and 24 months after Hugo and 6 and 28 months after Andrew provided strong evidence for the hypothesized model: Perceived support mediated the long-term effects on distress of both scope of disaster exposure and postdisaster received support. Theoretical and application issues of social support are discussed.

Exploring Environmental Factors in Nursing Workplaces That Promote Psychological Resilience: Constructing a Unified Theoretical Model.

PubMed

Cusack, Lynette; Smith, Morgan; Hegney, Desley; Rees, Clare S; Breen, Lauren J; Witt, Regina R; Rogers, Cath; Williams, Allison; Cross, Wendy; Cheung, Kin

2016-01-01

Building nurses' resilience to complex and stressful practice environments is necessary to keep skilled nurses in the workplace and ensuring safe patient care. A unified theoretical framework titled Health Services Workplace Environmental Resilience Model (HSWERM), is presented to explain the environmental factors in the workplace that promote nurses' resilience. The framework builds on a previously-published theoretical model of individual resilience, which identified the key constructs of psychological resilience as self-efficacy, coping and mindfulness, but did not examine environmental factors in the workplace that promote nurses' resilience. This unified theoretical framework was developed using a literary synthesis drawing on data from international studies and literature reviews on the nursing workforce in hospitals. The most frequent workplace environmental factors were identified, extracted and clustered in alignment with key constructs for psychological resilience. Six major organizational concepts emerged that related to a positive resilience-building workplace and formed the foundation of the theoretical model. Three concepts related to nursing staff support (professional, practice, personal) and three related to nursing staff development (professional, practice, personal) within the workplace environment. The unified theoretical model incorporates these concepts within the workplace context, linking to the nurse, and then impacting on personal resilience and workplace outcomes, and its use has the potential to increase staff retention and quality of patient care.

Foundations of reusable and interoperable facet models using category theory

PubMed Central

2016-01-01

Faceted browsing has become ubiquitous with modern digital libraries and online search engines, yet the process is still difficult to abstractly model in a manner that supports the development of interoperable and reusable interfaces. We propose category theory as a theoretical foundation for faceted browsing and demonstrate how the interactive process can be mathematically abstracted. Existing efforts in facet modeling are based upon set theory, formal concept analysis, and light-weight ontologies, but in many regards, they are implementations of faceted browsing rather than a specification of the basic, underlying structures and interactions. We will demonstrate that category theory allows us to specify faceted objects and study the relationships and interactions within a faceted browsing system. Resulting implementations can then be constructed through a category-theoretic lens using these models, allowing abstract comparison and communication that naturally support interoperability and reuse. PMID:27942248

ECUT: Energy Conversion and Utilization Technologies program. Heterogeneous catalysis modeling program concept

NASA Technical Reports Server (NTRS)

Voecks, G. E.

1983-01-01

Insufficient theoretical definition of heterogeneous catalysts is the major difficulty confronting industrial suppliers who seek catalyst systems which are more active, selective, and stable than those currently available. In contrast, progress was made in tailoring homogeneous catalysts to specific reactions because more is known about the reaction intermediates promoted and/or stabilized by these catalysts during the course of reaction. However, modeling heterogeneous catalysts on a microscopic scale requires compiling and verifying complex information on reaction intermediates and pathways. This can be achieved by adapting homogeneous catalyzed reaction intermediate species, applying theoretical quantum chemistry and computer technology, and developing a better understanding of heterogeneous catalyst system environments. Research in microscopic reaction modeling is now at a stage where computer modeling, supported by physical experimental verification, could provide information about the dynamics of the reactions that will lead to designing supported catalysts with improved selectivity and stability.

Exact Solutions of Burnt-Bridge Models for Molecular Motor Transport

NASA Astrophysics Data System (ADS)

Morozov, Alexander; Pronina, Ekaterina; Kolomeisky, Anatoly; Artyomov, Maxim

2007-03-01

Transport of molecular motors, stimulated by interactions with specific links between consecutive binding sites (called ``bridges''), is investigated theoretically by analyzing discrete-state stochastic ``burnt-bridge'' models. When an unbiased diffusing particle crosses the bridge, the link can be destroyed (``burned'') with a probability p, creating a biased directed motion for the particle. It is shown that for probability of burning p=1 the system can be mapped into one-dimensional single-particle hopping model along the periodic infinite lattice that allows one to calculate exactly all dynamic properties. For general case of p<1 a new theoretical method is developed, and dynamic properties are computed explicitly. Discrete-time and continuous-time dynamics, periodic and random distribution of bridges and different burning dynamics are analyzed and compared. Theoretical predictions are supported by extensive Monte Carlo computer simulations. Theoretical results are applied for analysis of the experiments on collagenase motor proteins.

Transactors, Transformers and Beyond. A Multi-Method Development of a Theoretical Typology of Leadership.

ERIC Educational Resources Information Center

Pearce, Craig L.; Sims, Henry P., Jr.; Cox, Jonathan F.; Ball, Gail; Schnell, Eugene; Smith, Ken A.; Trevino, Linda

2003-01-01

To extend the transactional-transformational model of leadership, four theoretical behavioral types of leadership were developed based on literature review and data from studies of executive behavior (n=253) and subordinate attitudes (n=208). Confirmatory factor analysis of a third data set (n=702) support the existence of four leadership types:…

Peer Interventions to Promote Health: Conceptual Considerations

PubMed Central

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

2013-01-01

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

Remarkable NO oxidation on single supported platinum atoms

DOE PAGES

Narula, Chaitanya K.; Allard, Lawrence F.; Stocks, G. M.; ...

2014-11-28

Our first-principles density functional theoretical modeling suggests that NO oxidation is feasible on fully oxidized single θ-alumina-supported platinum atoms via a modified Langmuir-Hinshelwood pathway. This is in contrast to the known decrease in NO oxidation activity of supported platinum with decreasing Pt particle size believed to be due to increased platinum oxidation. In order to validate our theoretical study, we evaluated single θ-Al 2O 3-supported platinum atoms and found them to exhibit remarkable NO oxidation activity. A comparison of turnover frequencies (TOF) of single supported Pt atoms with those of platinum particles for NO oxidation shows that single supported Ptmore » atoms are as active as fully formed platinum particles. The overall picture of NO oxidation on supported Pt is that NO oxidation activity decreases with decreasing Pt particle size but accelerates when Pt is present only as single atoms.« less

How Does Insightful and Emotional Disclosure Bring Potential Health Benefits?: Study Based on Online Support Groups for Women with Breast Cancer

PubMed Central

Shim, Minsun; Cappella, Joseph N.; Han, Jeong Yeob

2014-01-01

Despite much research on the beneficial effects of written disclosure, relatively little attention has been paid to specifying the mechanism underlying the effects. Building upon the two theoretical models (the cognitive adaptation model and the emotional exposure-habituation model), this research focused on two aspects of disclosure content—insights and emotions—and examined how women with breast cancer benefit from written disclosure in online support groups. Using survey data collected at baseline and after four months and messages posted in bulletin-board-type online groups in between, we analyzed how the content of disclosive messages predicted health outcomes. Disclosure of insights led to greater improvements in health self-efficacy, emotional well-being, and functional well-being, which was mediated by lowered breast cancer concerns. Disclosure of negative emotions did not have main effects on health outcomes; instead, it weakened the unfavorable association between concerns at baseline and functional well-being at follow-up. Our findings support both theoretical models, but in regard to different aspects of disclosure content. PMID:25568496

The Emergence of Family-specific Support Constructs: Cross-level Effects of Family-supportive Supervision and Family-Supportive Organization Perceptions on Individual Outcomes.

PubMed

Hill, Rachel T; Matthews, Russell A; Walsh, Benjamin M

2016-12-01

Implicit to the definitions of both family-supportive supervision (FSS) and family-supportive organization perceptions (FSOP) is the argument that these constructs may manifest at a higher (e.g. group or organizational) level. In line with these conceptualizations, grounded in tenants of conservation of resources theory, we argue that FSS and FSOP, as universal resources, are emergent constructs at the organizational level, which have cross-level effects on work-family conflict and turnover intentions. To test our theoretically derived hypotheses, a multilevel model was examined in which FSS and FSOP at the unit level predict individual work-to-family conflict, which in turn predicts turnover intentions. Our hypothesized model was generally supported. Collectively, our results point to FSOP serving as an explanatory mechanism of the effects that mutual perceptions of FSS have on individual experiences of work-to-family conflict and turnover intentions. Lagged (i.e. overtime) cross-level effects of the model were also confirmed in supplementary analyses. Our results extend our theoretical understanding of FSS and FSOP by demonstrating the utility of conceptualizing them as universal resources, opening up a variety of avenues for future research. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

New Look at Social Support: A Theoretical Perspective on Thriving through Relationships

PubMed Central

Feeney, Brooke C.; Collins, Nancy L.

2017-01-01

Close and caring relationships are undeniably linked to health and well-being at all stages in the lifespan. Yet the specific pathways through which close relationships promote optimal well-being are not well understood. In this article, we present a model of thriving through relationships to provide a theoretical foundation for identifying the specific interpersonal processes that underlie the effects of close relationships on thriving. This model highlights two life contexts through which people may potentially thrive (coping successfully with life’s adversities and actively pursuing life opportunities for growth and development), it proposes two relational support functions that are fundamental to the experience of thriving in each life context, and it identifies mediators through which relational support is likely to have long-term effects on thriving. This perspective highlights the need for researchers to take a new look at social support by conceptualizing it as an interpersonal process with a focus on thriving. PMID:25125368

Nurse characteristics, leadership, safety climate, emotional labour and intention to stay for nurses: a structural equation modelling approach.

PubMed

Liang, Hui-Yu; Tang, Fu-In; Wang, Tze-Fang; Lin, Kai-Ching; Yu, Shu

2016-12-01

The aim of this study was to propose a theoretical model and apply it to examine the structural relationships among nurse characteristics, leadership characteristics, safety climate, emotional labour and intention to stay for hospital nurses. Global nursing shortages negatively affect the quality of care. The shortages can be reduced by retaining nurses. Few studies have independently examined the relationships among leadership, safety climate, emotional labour and nurses' intention to stay; more comprehensive theoretical foundations for examining nurses' intention to stay and its related factors are lacking. Cross-sectional. A purposive sample of 414 full-time nurses was recruited from two regional hospitals in Taiwan. A structured questionnaire was used to collect data from November 2013-June 2014. Structural equation modelling was employed to test the theoretical models of the relationships among the constructs. Our data supported the theoretical model. Intention to stay was positively correlated with age and the safety climate, whereas working hours per week and emotional labour were negatively correlated. The nursing position and transformational leadership indirectly affected intention to stay; this effect was mediated separately by emotional labour and the safety climate. Our data supported the model fit. Our findings provide practical implications for healthcare organizations and administrators to increase nurses' intent to stay. Strategies including a safer climate, appropriate working hours and lower emotional labour can directly increase nurses' intent to stay. Transformational leadership did not directly influence nurses' intention to stay; however, it reduced emotional labour, thereby increasing intention to stay. © 2016 John Wiley & Sons Ltd.

Testing a Theoretical Model of Immigration Transition and Physical Activity.

PubMed

Chang, Sun Ju; Im, Eun-Ok

2015-01-01

The purposes of the study were to develop a theoretical model to explain the relationships between immigration transition and midlife women's physical activity and test the relationships among the major variables of the model. A theoretical model, which was developed based on transitions theory and the midlife women's attitudes toward physical activity theory, consists of 4 major variables, including length of stay in the United States, country of birth, level of acculturation, and midlife women's physical activity. To test the theoretical model, a secondary analysis with data from 127 Hispanic women and 123 non-Hispanic (NH) Asian women in a national Internet study was used. Among the major variables of the model, length of stay in the United States was negatively associated with physical activity in Hispanic women. Level of acculturation in NH Asian women was positively correlated with women's physical activity. Country of birth and level of acculturation were significant factors that influenced physical activity in both Hispanic and NH Asian women. The findings support the theoretical model that was developed to examine relationships between immigration transition and physical activity; it shows that immigration transition can play an essential role in influencing health behaviors of immigrant populations in the United States. The NH theoretical model can be widely used in nursing practice and research that focus on immigrant women and their health behaviors. Health care providers need to consider the influences of immigration transition to promote immigrant women's physical activity.

Au and Pt nanoparticle supported catalysts tailored for H-2 production: From models to powder catalysts

DOE PAGES

T. D. Nguyen-Phan; Baber, A. E.; Rodriguez, J. A.; ...

2015-12-10

The use of metal nanoparticles (NPs), including Au and Pt, supported over oxides has been pivotal, and is ever increasing in enabling catalytic reactions which target the production of hydrogen. We review here the most recent works pertaining to the fundamental understanding of the structure, morphology, growth, characterization, and intrinsic phenomenological properties of Au– and Pt– based catalysts that influence the reactivity and selectivity to target hydrogen production. We draw on surface science and theoretical methods of model and powder catalysts using high resolution imaging, spectroscopy, scattering experiments, and theoretical studies. Based on these insights we identify key aspects ofmore » studies of supported metal nanoparticle (NP) catalysts for several reactions. The main focus of this review is on the intersection of catalytic chemistry related to the water-gas shift (WGS), oxygenate steam reforming (OSR), and solarassisted reactions (SAR).« less

Fear and Loving in Las Vegas: Evolution, Emotion, and Persuasion.

PubMed

Griskevicius, Vladas; Goldstein, Noah J; Mortensen, Chad R; Sundie, Jill M; Cialdini, Robert B; Kenrick, Douglas T

2009-06-01

How do arousal-inducing contexts, such as frightening or romantic television programs, influence the effectiveness of basic persuasion heuristics? Different predictions are made by three theoretical models: A general arousal model predicts that arousal should increase effectiveness of heuristics; an affective valence model predicts that effectiveness should depend on whether the context elicits positive or negative affect; an evolutionary model predicts that persuasiveness should depend on both the specific emotion that is elicited and the content of the particular heuristic. Three experiments examined how fear-inducing versus romantic contexts influenced the effectiveness of two widely used heuristics-social proof (e.g., "most popular") and scarcity (e.g., "limited edition"). Results supported predictions from an evolutionary model, showing that fear can lead scarcity appeals to be counter-persuasive, and that romantic desire can lead social proof appeals to be counter-persuasive. The findings highlight how an evolutionary theoretical approach can lead to novel theoretical and practical marketing insights.

Communication competence, social support, and depression among college students: a model of facebook and face-to-face support network influence.

PubMed

Wright, Kevin B; Rosenberg, Jenny; Egbert, Nicole; Ploeger, Nicole A; Bernard, Daniel R; King, Shawn

2013-01-01

This study examined the influence of the social networking site Facebook and face-to-face support networks on depression among (N = 361) college students. The authors used the Relational Health Communication Competence Model as a framework for examining the influence of communication competence on social support network satisfaction and depression. Moreover, they examined the influence of interpersonal and social integrative motives as exogenous variables. On the basis of previous work, the authors propose and test a theoretical model using structural equation modeling. The results indicated empirical support for the model, with interpersonal motives predicting increased face-to-face and computer-mediated competence, increased social support satisfaction with face-to-face and Facebook support, and lower depression scores. The implications of the findings for theory, key limitations, and directions for future research are discussed.

The robust nature of the biopsychosocial model challenge and threat: a reply to Wright and Kirby.

PubMed

Blascovich, Jim; Mendes, Wendy Berry; Tomaka, Joe; Salomon, Kristen; Seery, Mark

2003-01-01

This article responds to Wright and Kirby's (this issue) critique of our biopsychosocial (BPS) analysis of challenge and threat motivation. We counter their arguments by reviewing the current state of our theory as well as supporting data, then turn to their specific criticisms. We believe that Wright and Kirby failed to accurately represent the corpus of our work, including both our theoretical model and its supporting data. They critiqued our model from a contextual, rational-economic perspective that ignores the complexity and subjectivity of person-person and person-environmental interactions as well as nonconscious influences. Finally, they provided criticisms regarding possible underspecificity of antecedent components of our model that do not so much indicate theoretical flaws as provide important and interesting questions for future research. We conclude by affirming that our BPS model of challenge and threat is an evolving, generative theory directed toward understanding the complexity of personality and social psychological factors underlying challenge and threat states.

Building Intercultural Competency in the Language Immersion Montessori Classroom

ERIC Educational Resources Information Center

Carver-Akers, Kateri

2013-01-01

In her article entitled, "Theoretical Reflections: Intercultural Framework / Model" Darla Deardorff provides the Pyramid Model of Cultural Competency. At the bottom of the pyramid she places three "Requisite Attitudes," which support the remaining three blocks above ("Knowledge & Comprehension/Skills,"…

Developing, Testing, and Using Theoretical Models for Promoting Quality in Education

ERIC Educational Resources Information Center

Creemers, Bert; Kyriakides, Leonidas

2015-01-01

This paper argues that the dynamic model of educational effectiveness can be used to establish stronger links between educational effectiveness research (EER) and school improvement. It provides research evidence to support the validity of the model. Thus, the importance of using the dynamic model to establish an evidence-based and theory-driven…

A Multi-Stage Maturity Model for Long-Term IT Outsourcing Relationship Success

ERIC Educational Resources Information Center

Luong, Ming; Stevens, Jeff

2015-01-01

The Multi-Stage Maturity Model for Long-Term IT Outsourcing Relationship Success, a theoretical stages-of-growth model, explains long-term success in IT outsourcing relationships. Research showed the IT outsourcing relationship life cycle consists of four distinct, sequential stages: contract, transition, support, and partnership. The model was…

Feedback Model to Support Designers of Blended-Learning Courses

ERIC Educational Resources Information Center

Hummel, Hans G. K.

2006-01-01

Although extensive research has been carried out, describing the role of feedback in education, and many theoretical models are yet available, procedures and guidelines for actually designing and implementing feedback in practice have remained scarce so far. This explorative study presents a preliminary six-phase design model for feedback…

The Concept of Adjustment: A Structural Model.

ERIC Educational Resources Information Center

Dodds, A.; And Others

1994-01-01

This study analyzed scores of 469 British adult clients with recent loss of sight on the Nottingham Adjustment Scale using LISREL structural modeling techniques. Results supported a theoretical model of the self in terms of two latent factors--internal self-worth and self as agent. Implications for rehabilitation and intervention with cognitive…

Investigating the LGBTQ Responsive Model for Supervision of Group Work

ERIC Educational Resources Information Center

Luke, Melissa; Goodrich, Kristopher M.

2013-01-01

This article reports an investigation of the LGBTQ Responsive Model for Supervision of Group Work, a trans-theoretical supervisory framework to address the needs of lesbian, gay, bisexual, transgender, and questioning (LGBTQ) persons (Goodrich & Luke, 2011). Findings partially supported applicability of the LGBTQ Responsive Model for Supervision…

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

PubMed

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.

[L'impiego dell'ICNP® nella formazione infermieristica con modelli teorici infermieristici: una revisione della letteratura].

PubMed

Macchi, Barbara; Sironi, Cecilia; Di Mauro, Stefania; Ausili, Davide

2016-01-01

The International Classification for Nursing Practice (ICNP®) is the only nursing terminology that has been accepted within the Family of International Classification of the World Health Organization. The academic teaching of ICNP® could contribute to improve nursing clinical practice. However, standards for its implementation in undergraduate nursing education together with a nursing theoretical model are not available. To know the state of the art about the use of ICNP® in undergraduate nursing education and its use with a nursing theoretical model. A narrative literature review was conducted searching main health scientific databases and including monographs, statements from international associations, and published conference papers. Available literature about ICNP® implementation in nursing education and its use with theoretical models is limited. Results supported the organization of a specific course on ICNP® before clinical teaching programs, the development of paper or electronic ICNP® based educational tools, and the use of active learning strategies. Only three experiences reporting the use of ICNP® with theoretical models have been found. Both the use of ICNP® in nursing undergraduate education and its use according to one or more nursing theoretical models, could help students to learn nursing process. However, weak recommendations can be found in the literature to orient ICNP® implementation in undergraduate nursing education and/or with an explicit theoretical framework. Further studies focusing on these issues are strongly needed.

Exploring Environmental Factors in Nursing Workplaces That Promote Psychological Resilience: Constructing a Unified Theoretical Model

PubMed Central

Cusack, Lynette; Smith, Morgan; Hegney, Desley; Rees, Clare S.; Breen, Lauren J.; Witt, Regina R.; Rogers, Cath; Williams, Allison; Cross, Wendy; Cheung, Kin

2016-01-01

Building nurses' resilience to complex and stressful practice environments is necessary to keep skilled nurses in the workplace and ensuring safe patient care. A unified theoretical framework titled Health Services Workplace Environmental Resilience Model (HSWERM), is presented to explain the environmental factors in the workplace that promote nurses' resilience. The framework builds on a previously-published theoretical model of individual resilience, which identified the key constructs of psychological resilience as self-efficacy, coping and mindfulness, but did not examine environmental factors in the workplace that promote nurses' resilience. This unified theoretical framework was developed using a literary synthesis drawing on data from international studies and literature reviews on the nursing workforce in hospitals. The most frequent workplace environmental factors were identified, extracted and clustered in alignment with key constructs for psychological resilience. Six major organizational concepts emerged that related to a positive resilience-building workplace and formed the foundation of the theoretical model. Three concepts related to nursing staff support (professional, practice, personal) and three related to nursing staff development (professional, practice, personal) within the workplace environment. The unified theoretical model incorporates these concepts within the workplace context, linking to the nurse, and then impacting on personal resilience and workplace outcomes, and its use has the potential to increase staff retention and quality of patient care. PMID:27242567

Social Support, Infant Temperament, and Parenting Self-Efficacy: A Mediational Model of Postpartum Depression

ERIC Educational Resources Information Center

Cutrona, Carolyn E.; Troutman, Beth R.

1986-01-01

Infant temperamental difficulty was strongly related to mothers' level of postpartum depression, both directly and through the mediation of parenting self-efficacy. Social support appeared to function protectively against depression, primarily through self-efficacy. Practical and theoretical implications are discussed. (Author/RH)

From Decent Work to Decent Lives: Positive Self and Relational Management (PS&RM) in the Twenty-First Century

PubMed Central

Di Fabio, Annamaria; Kenny, Maureen E.

2016-01-01

The aim of the present study is to empirically test the theoretical model, Positive Self and Relational Management (PS&RM), for a sample of 184 Italian university students. The PS&RM model specifies the development of individuals' strengths, potentials, and talents across the lifespan and with regard to the dialect of self in relationship. PS&RM is defined theoretically by three constructs: Positive Lifelong Life Management, Positive Lifelong Self-Management, Positive Lifelong Relational Management. The three constructs are operationalized as follows: Positive Lifelong Life Management is measured by the Positive and Negative Affect Schedule (PANAS), the Satisfaction With Life Scale (SWLS), the Meaningful Life Measure (MLM), and the Authenticity Scale (AS); Positive Lifelong Self-Management is measured by the Intrapreneurial Self-Capital Scale (ISC), the Career Adapt-Abilities Scale (CAAS), and the Life Project Reflexivity Scale (LPRS); and Positive Lifelong Relational Management is measured by the Trait Emotional Intelligence Questionnaire (TEIQue), the Multidimensional Scale for Perceived Social Support (MSPSS), and the Positive Relational Management Scale (PRMS). Confirmatory factor analysis of the PS&RM model was completed using structural equation modeling. The theoretical PS&RM model was empirically tested as defined by the three hypothesized constructs. Empirical support for this model offers a framework for further research and the design of preventive interventions to promote decent work and decent lives in the twenty-first century. PMID:27047406

For Fit's Sake: A Norms-Based Approach to Healthy Behaviors Through Influence of Presumed Media Influence.

PubMed

Ho, Shirley S; Lee, Edmund W J; Ng, Kaijie; Leong, Grace S H; Tham, Tiffany H M

2016-09-01

Based on the influence of presumed media influence (IPMI) model as the theoretical framework, this study examines how injunctive norms and personal norms mediate the influence of healthy lifestyle media messages on public intentions to engage in two types of healthy lifestyle behaviors-physical activity and healthy diet. Nationally representative data collected from 1,055 adults in Singapore demonstrate partial support for the key hypotheses that make up the extended IPMI model, highlighting the importance of a norms-based approach in health communication. Our results indicate that perceived media influence on others indirectly shaped public intentions to engage in healthy lifestyle behaviors through personal norms and attitude, providing partial theoretical support for the extended IPMI model. Practical implications for health communicators in designing health campaigns media messages to motivate the public to engage in healthy lifestyle are discussed.

Carbon deposition during oxygen production using high temperature electrolysis and mitigation methods

NASA Astrophysics Data System (ADS)

Bernadowski, Timothy Adam, Jr.

Carbon dioxide in the Martian atmosphere can be converted to oxygen during high temperature electrolysis for use in life-support and fuel systems on manned missions to the red planet. During electrolysis of carbon dioxide to produce oxygen, carbon can deposit on the electrolysis cell resulting in lower efficiency and possibly cell damage. This would be detrimental, especially when the oxygen product is used as the key element of a space life support system. In this thesis, a theoretical model was developed to predict hazardous carbon deposition conditions under various operating conditions within the Martian atmosphere. The model can be used as a guide to determine the ideal operating conditions of the high-temperature oxygen production system. A parallel experimental investigation is underway to evaluate the accuracy of the theoretical model. The experimental design, cell fabrication, and some preliminary results as well as future work recommendations are also presented in this thesis.

Exploring the relationship between volunteering and hospice sustainability in the UK: a theoretical model.

PubMed

Scott, Ros; Jindal-Snape, Divya; Manwaring, Gaye

2018-05-02

To explore the relationship between volunteering and the sustainability of UK voluntary hospices. A narrative literature review was conducted to inform the development of a theoretical model. Eight databases were searched: CINAHL (EBSCO), British Nursing Index, Intute: Health and Life Sciences, ERIC, SCOPUS, ASSIA (CSA), Cochrane Library and Google Scholar. A total of 90 documents were analysed. Emerging themes included the importance of volunteering to the hospice economy and workforce, the quality of services, and public and community support. Findings suggest that hospice sustainability is dependent on volunteers; however, the supply and retention of volunteers is affected by internal and external factors. A theoretical model was developed to illustrate the relationship between volunteering and hospice sustainability. It demonstrates the factors necessary for hospice sustainability and the reciprocal impact that these factors and volunteering have on each other. The model has a practical application as an assessment framework and strategic planning tool.

Research in Theoretical Particle Physics

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

Ralston, John P.

This document is the final report on activity of the University of Kansas theory group supported under DOE Grant Number DE-FG02-04ER14308, ending April 30, 3013. The report covers the most recent three year period period May 1, 2010-April 30, 2013. Faculty supported by the grant during the period were Danny Marfatia (co-I), Douglas McKay (emeritus) and John Ralston (PI). The group's research topics and accomplishments covered numerous different topics subsumed under the {\\it the Energy Frontier, the Intensity Frontier}, and {\\it the Cosmic Frontier}. Many theoretical and experimental results related to the Standard Model and models of new physics weremore » published during the reporting period. The group's research emphasis has been on challenging and confronting {\\it Anything that is Observable} about the physical Universe.« less

Theoretical Assessment of the Impact of Climatic Factors in a Vibrio Cholerae Model.

PubMed

Kolaye, G; Damakoa, I; Bowong, S; Houe, R; Békollè, D

2018-05-04

A mathematical model for Vibrio Cholerae (V. Cholerae) in a closed environment is considered, with the aim of investigating the impact of climatic factors which exerts a direct influence on the bacterial metabolism and on the bacterial reservoir capacity. We first propose a V. Cholerae mathematical model in a closed environment. A sensitivity analysis using the eFast method was performed to show the most important parameters of the model. After, we extend this V. cholerae model by taking account climatic factors that influence the bacterial reservoir capacity. We present the theoretical analysis of the model. More precisely, we compute equilibria and study their stabilities. The stability of equilibria was investigated using the theory of periodic cooperative systems with a concave nonlinearity. Theoretical results are supported by numerical simulations which further suggest the necessity to implement sanitation campaigns of aquatic environments by using suitable products against the bacteria during the periods of growth of aquatic reservoirs.

Lateral-Torsional Buckling Instability Caused by Individuals Walking on Wood Composite I-Joists

NASA Astrophysics Data System (ADS)

Villasenor Aguilar, Jose Maria

Recent research has shown that a significant number of the falls from elevation occur when laborers are working on unfinished structures. Workers walking on wood I-joists on roofs and floors are prone to fall hazards. Wood I-joists have been replacing dimension lumber for many floor systems and a substantial number of roof systems in light-frame construction. Wood I-joists are designed to resist axial stresses on the flanges and shear stresses on the web while minimizing material used. However, wood I-joists have poor resistance to applied lateral and torsional loads and are susceptible to lateral-torsional buckling instability. Workers walking on unbraced or partially braced wood I-joists can induce axial and lateral forces as well as twist. Experimental testing demonstrated that workers cause lateral-torsional buckling instability in wood I-joists. However, no research was found related to the lateral-torsional buckling instability induced by individuals walking on the wood I-joists. Furthermore, no research was found considering the effects of the supported end conditions and partial bracing in the lateral-torsional buckling instability of wood I-joists. The goal of this research was to derive mathematical models to predict the dynamic lateral-torsional buckling instability of wood composite I-joists loaded by individuals walking considering different supported end conditions and bracing system configurations. The dynamic lateral-torsional buckling instability was analyzed by linearly combining the static lateral-torsional buckling instability with the lateral bending motion of the wood Ijoists. Mathematical models were derived to calculate the static critical loads for the simply supported end condition and four wood I-joist hanger supported end conditions. Additionally, mathematical models were derived to calculate the dynamic maximum lateral displacements and positions of the individual walking on the wood Ijoists for the same five different supported end conditions. Three different lean-on bracing systems were investigated, non-bracing, one-bracing, and two-bracing systems. Mathematical models were derived to calculate the amount of constraint due to the lean-on bracing system. The derived mathematical models were validated by comparison to data from testing for all supported end conditions and bracing systems. The predicted critical loads using the static buckling theoretical models for the non-bracing system and the static buckling theoretical models combined with the bracing theoretical models for the simply and hanger supported end conditions agreed well with the critical loads obtained from testing for the two wood I-joist sizes investigated. The predicted maximum lateral displacements and individual positions using the bending motion theoretical models for the simply and hanger supported end conditions agreed well with the corresponding maximum lateral displacements and individual positions obtained from testing for both wood I-joist sizes. Results showed that; a) the supported end condition influenced the critical loads, maximum lateral displacements and individual positions, b) the bracing system increased the critical loads and reduced the maximum lateral displacements, c) the critical load increased as the load position displaced away from the wood I-joist mid-span, d) the critical load reduced as the initial lateral displacement of the wood I-joist increased and e) the wood I-joist mid-span was the critical point in the dynamic lateral-torsional buckling instability.

Construction of an Integrated Positive Youth Development Conceptual Framework for the Prevention of the Use of Psychotropic Drugs among Adolescents

PubMed Central

Lee, Tak Yan

2011-01-01

This is a theoretical paper with an aim to construct an integrated conceptual framework for the prevention of adolescents' use and abuse of psychotropic drugs. This paper first reports the subjective reasons for adolescents' drug use and abuse in Hong Kong and reviews the theoretical underpinnings. Theories of drug use and abuse, including neurological, pharmacological, genetic predisposition, psychological, and sociological theories, were reviewed. It provides a critical re-examination of crucial factors that support the construction of a conceptual framework for primary prevention of adolescents' drug use and abuse building on, with minor revision, the model of victimization and substance abuse among women presented by Logan et al. This revised model provides a comprehensive and coherent framework synthesized from theories of drug abuse. This paper then provides empirical support for integrating a positive youth development perspective in the revised model. It further explains how the 15 empirically sound constructs identified by Catalano et al. and used in a positive youth development program, the Project P.A.T.H.S., relate generally to the components of the revised model to formulate an integrated positive youth development conceptual framework for primary prevention of adolescent drug use. Theoretical and practical implications as well as limitations and recommendations are discussed. PMID:22194671

Psychological Pathways Linking Social Support to Health Outcomes: A Visit with the “Ghosts” of Research Past, Present, and Future

PubMed Central

Uchino, Bert N.; Bowen, Kimberly; Carlisle, McKenzie; Birmingham, Wendy

2012-01-01

Contemporary models postulate the importance of psychological mechanisms linking perceived and received social support to physical health outcomes. In this review, we examine studies that directly tested the potential psychological mechanisms responsible for links between social support and health-relevant physiological processes (1980s to 2010). Inconsistent with existing theoretical models, no evidence was found that psychological mechanisms such as depression, perceived stress, and other affective processes are directly responsible for links between support and health. We discuss the importance of considering statistical/design issues, emerging conceptual perspectives, and limitations of our existing models for future research aimed at elucidating the psychological mechanisms responsible for links between social support and physical health outcomes. PMID:22326104

Lung Cancer Screening Participation: Developing a Conceptual Model to Guide Research

PubMed Central

Carter-Harris, Lisa; Davis, Lorie L.; Rawl, Susan M.

2017-01-01

Purpose To describe the development of a conceptual model to guide research focused on lung cancer screening participation from the perspective of the individual in the decision-making process. Methods Based on a comprehensive review of empirical and theoretical literature, a conceptual model was developed linking key psychological variables (stigma, medical mistrust, fatalism, worry, and fear) to the health belief model and precaution adoption process model. Results Proposed model concepts have been examined in prior research of either lung or other cancer screening behavior. To date, a few studies have explored a limited number of variables that influence screening behavior in lung cancer specifically. Therefore, relationships among concepts in the model have been proposed and future research directions presented. Conclusion This proposed model is an initial step to support theoretically based research. As lung cancer screening becomes more widely implemented, it is critical to theoretically guide research to understand variables that may be associated with lung cancer screening participation. Findings from future research guided by the proposed conceptual model can be used to refine the model and inform tailored intervention development. PMID:28304262

Lung Cancer Screening Participation: Developing a Conceptual Model to Guide Research.

PubMed

Carter-Harris, Lisa; Davis, Lorie L; Rawl, Susan M

2016-11-01

To describe the development of a conceptual model to guide research focused on lung cancer screening participation from the perspective of the individual in the decision-making process. Based on a comprehensive review of empirical and theoretical literature, a conceptual model was developed linking key psychological variables (stigma, medical mistrust, fatalism, worry, and fear) to the health belief model and precaution adoption process model. Proposed model concepts have been examined in prior research of either lung or other cancer screening behavior. To date, a few studies have explored a limited number of variables that influence screening behavior in lung cancer specifically. Therefore, relationships among concepts in the model have been proposed and future research directions presented. This proposed model is an initial step to support theoretically based research. As lung cancer screening becomes more widely implemented, it is critical to theoretically guide research to understand variables that may be associated with lung cancer screening participation. Findings from future research guided by the proposed conceptual model can be used to refine the model and inform tailored intervention development.

Towards a Theoretical Framework for Understanding PGCE Student Teacher Learning in the Wild Coast Rural Schools' Partnership Project

ERIC Educational Resources Information Center

Pennefather, Jane

2016-01-01

This article focuses on a theoretical model that I am developing in order to understand student teacher learning in a rural context and the enabling conditions that can support this learning. The question of whether a supervised teaching practice in a rural context can contribute to the development of student teacher professional learning and…

Mathematical Modelling and the Learning Trajectory: Tools to Support the Teaching of Linear Algebra

ERIC Educational Resources Information Center

Cárcamo Bahamonde, Andrea Dorila; Fortuny Aymemí, Josep Maria; Gómez i Urgellés, Joan Vicenç

2017-01-01

In this article we present a didactic proposal for teaching linear algebra based on two compatible theoretical models: emergent models and mathematical modelling. This proposal begins with a problematic situation related to the creation and use of secure passwords, which leads students toward the construction of the concepts of spanning set and…

The mathematical and theoretical biology institute--a model of mentorship through research.

PubMed

Camacho, Erika T; Kribs-Zaleta, Christopher M; Wirkus, Stephen

2013-01-01

This article details the history, logistical operations, and design philosophy of the Mathematical and Theoretical Biology Institute (MTBI), a nationally recognized research program with an 18-year history of mentoring researchers at every level from high school through university faculty, increasing the number of researchers from historically underrepresented minorities, and motivating them to pursue research careers by allowing them to work on problems of interest to them and supporting them in this endeavor. This mosaic profile highlights how MTBI provides a replicable multi-level model for research mentorship.

Treatment of Sexual Offenders: Research, Best Practices, and Emerging Models

ERIC Educational Resources Information Center

Yates, Pamela M.

2013-01-01

Treatment of sexual offenders has evolved substantially over the years; various theoretical and practice models of treatment been developed, modified, refined, and proposed over time. The predominant current recommended approach, supported by research, adheres to specific principles of effective correctional intervention, follows a…

A New Transcendence Model of Identity Construction

ERIC Educational Resources Information Center

Elliott, Christopher L. Wilcox

2012-01-01

What does it mean for college men to be authentic? How can we support their efforts to transcend their own immediate needs? And what roles do trusted others play in one's construction of identity? This article describes a preliminary new theoretical model--a Transcendence Model of Identity Construction--based on original research studying…

The Detection and Correction of Bias in Student Ratings of Instruction.

ERIC Educational Resources Information Center

Haladyna, Thomas; Hess, Robert K.

1994-01-01

A Rasch model was used to detect and correct bias in Likert rating scales used to assess student perceptions of college teaching, using a database of ratings. Statistical corrections were significant, supporting the model's potential utility. Recommendations are made for a theoretical rationale and further research on the model. (Author/MSE)

Introducing an Intervention Model for Fostering Affective Involvement with Persons Who Are Congenitally Deafblind

ERIC Educational Resources Information Center

Martens, Marga A. W.; Janssen, Marleen J.; Ruijssenaars, Wied A. J. J. M.; Riksen-Walraven, J. Marianne

2014-01-01

The article presented here introduces the Intervention Model for Affective Involvement (IMAI), which was designed to train staff members (for example, teachers, caregivers, support workers) to foster affective involvement during interaction and communication with persons who have congenital deaf-blindness. The model is theoretically underpinned,…

Knowledge and Opinion on the Nuclear Freeze: A Test of Three Models.

ERIC Educational Resources Information Center

Tankard, James W., Jr.

To explore how knowledge influences opinion in foreign policy, results of a survey on voter familiarity with and attitude toward nuclear policy issues were compared with three theoretical models of the knowledge/opinion relationship: (1) the enlightenment model--as knowledge increases, support for belligerent foreign policy stands decreases; (2)…

Meta-Theoretical Contributions to the Constitution of a Model-Based Didactics of Science

NASA Astrophysics Data System (ADS)

Ariza, Yefrin; Lorenzano, Pablo; Adúriz-Bravo, Agustín

2016-10-01

There is nowadays consensus in the community of didactics of science (i.e. science education understood as an academic discipline) regarding the need to include the philosophy of science in didactical research, science teacher education, curriculum design, and the practice of science education in all educational levels. Some authors have identified an ever-increasing use of the concept of `theoretical model', stemming from the so-called semantic view of scientific theories. However, it can be recognised that, in didactics of science, there are over-simplified transpositions of the idea of model (and of other meta-theoretical ideas). In this sense, contemporary philosophy of science is often blurred or distorted in the science education literature. In this paper, we address the discussion around some meta-theoretical concepts that are introduced into didactics of science due to their perceived educational value. We argue for the existence of a `semantic family', and we characterise four different versions of semantic views existing within the family. In particular, we seek to contribute to establishing a model-based didactics of science mainly supported in this semantic family.

The Safety Culture Enactment Questionnaire (SCEQ): Theoretical model and empirical validation.

PubMed

de Castro, Borja López; Gracia, Francisco J; Tomás, Inés; Peiró, José M

2017-06-01

This paper presents the Safety Culture Enactment Questionnaire (SCEQ), designed to assess the degree to which safety is an enacted value in the day-to-day running of nuclear power plants (NPPs). The SCEQ is based on a theoretical safety culture model that is manifested in three fundamental components of the functioning and operation of any organization: strategic decisions, human resources practices, and daily activities and behaviors. The extent to which the importance of safety is enacted in each of these three components provides information about the pervasiveness of the safety culture in the NPP. To validate the SCEQ and the model on which it is based, two separate studies were carried out with data collection in 2008 and 2014, respectively. In Study 1, the SCEQ was administered to the employees of two Spanish NPPs (N=533) belonging to the same company. Participants in Study 2 included 598 employees from the same NPPs, who completed the SCEQ and other questionnaires measuring different safety outcomes (safety climate, safety satisfaction, job satisfaction and risky behaviors). Study 1 comprised item formulation and examination of the factorial structure and reliability of the SCEQ. Study 2 tested internal consistency and provided evidence of factorial validity, validity based on relationships with other variables, and discriminant validity between the SCEQ and safety climate. Exploratory Factor Analysis (EFA) carried out in Study 1 revealed a three-factor solution corresponding to the three components of the theoretical model. Reliability analyses showed strong internal consistency for the three scales of the SCEQ, and each of the 21 items on the questionnaire contributed to the homogeneity of its theoretically developed scale. Confirmatory Factor Analysis (CFA) carried out in Study 2 supported the internal structure of the SCEQ; internal consistency of the scales was also supported. Furthermore, the three scales of the SCEQ showed the expected correlation patterns with the measured safety outcomes. Finally, results provided evidence of discriminant validity between the SCEQ and safety climate. We conclude that the SCEQ is a valid, reliable instrument supported by a theoretical framework, and it is useful to measure the enactment of safety culture in NPPs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Understanding the nanoscale local buckling behavior of vertically aligned MWCNT arrays with van der Waals interactions

NASA Astrophysics Data System (ADS)

Li, Yupeng; Kim, Hyung-Ick; Wei, Bingqing; Kang, Junmo; Choi, Jae-Boong; Nam, Jae-Do; Suhr, Jonghwan

2015-08-01

The local buckling behavior of vertically aligned carbon nanotubes (VACNTs) has been investigated and interpreted in the view of a collective nanotube response by taking van der Waals interactions into account. To the best of our knowledge, this is the first report on the case of collective VACNT behavior regarding van der Waals force among nanotubes as a lateral support effect during the buckling process. The local buckling propagation and development of VACNTs were experimentally observed and theoretically analyzed by employing finite element modeling with lateral support from van der Waals interactions among nanotubes. Both experimental and theoretical analyses show that VACNTs buckled in the bottom region with many short waves and almost identical wavelengths, indicating a high mode buckling. Furthermore, the propagation and development mechanism of buckling waves follow the wave damping effect.The local buckling behavior of vertically aligned carbon nanotubes (VACNTs) has been investigated and interpreted in the view of a collective nanotube response by taking van der Waals interactions into account. To the best of our knowledge, this is the first report on the case of collective VACNT behavior regarding van der Waals force among nanotubes as a lateral support effect during the buckling process. The local buckling propagation and development of VACNTs were experimentally observed and theoretically analyzed by employing finite element modeling with lateral support from van der Waals interactions among nanotubes. Both experimental and theoretical analyses show that VACNTs buckled in the bottom region with many short waves and almost identical wavelengths, indicating a high mode buckling. Furthermore, the propagation and development mechanism of buckling waves follow the wave damping effect. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr03581c

Religious Involvement, Humility, and Self-Rated Health

ERIC Educational Resources Information Center

Krause, Neal

2010-01-01

The purpose of this study is to develop and test a conceptual model that assesses the following theoretical linkages: (1) people who go to church more often tend to receive more spiritual support from fellow church members (i.e., encouragement to adopt religious teachings and principles); (2) individuals who get more frequent spiritual support are…

Predictors of Workplace Deviant Behaviour: HRD Agenda for Malaysian Support Personnel

ERIC Educational Resources Information Center

Alias, Mazni; Rasdi, Roziah Mohd; Ismail, Maimunah; Samah, Bahaman Abu

2013-01-01

Purpose: The purpose of this paper is to develop a theoretical model of the determinants of workplace deviant behaviour among support personnel in Malaysian Public Service organisations. Design/methodology/approach: This study is based on reviews of past studies on workplace deviant behaviour. To conduct the literature review, several keywords…

A Theoretical Model and New Test of Managerial Legitimacy in Work Teams

ERIC Educational Resources Information Center

Yoon, Jeongkoo; Thye, Shane

2011-01-01

This study examines endorsement and authorization as two social mechanisms that can induce perceptions of legitimacy for individuals who manage work teams. "Endorsement" is the support of a manager by one's own team members, whereas "authorization" is the support of a team manager stemming from a higher bureaucratic level.…

Stress and Social Support in Parents of Hyperactive Children.

ERIC Educational Resources Information Center

Miner, Joanne

The role of social support in moderating stress was examined in 65 parents of hyperactive children. The sample included 29 couples and 7 single mothers. The theoretical framework guiding the research was Lazarus' general model of stress. Each parent's psychological functioning was hypothesized to be a function of the severity of the child's…

The conditional indirect effect model of women's union participation: the moderating effect of perceived union tolerance for sexual harassment.

PubMed

Mellor, Steven; Golay, Leslie M

2014-01-01

We tested a theoretically trimmed model of union participation presented by Tetrick, Shore, McClurg, and Vandenberg (2007), in which perceived union instrumentality is expected to influence participation through perceived union support. This testing was accomplished as a precursor to testing a conditional indirect effect model of women's participation--in which perceived union tolerance for sexual harassment was expected to moderate the influence of perceived support on willingness to participate in union activities. In a sample of 326 women from multiple unions, we found support for the conditional model; the influence of perceived instrumentality on willingness to participate through perceived support was moderated by perceived tolerance for harassment; specifically, the influence through perceived support was weak when perceived tolerance was high. The implications of our results are discussed in reference to need support and women's participation.

The Alternative Peer Group: A Developmentally Appropriate Recovery Support Model for Adolescents.

PubMed

Nash, Angela; Collier, Crystal

2016-01-01

Recovery as the goal for substance use disorder treatment has been a key component of the Substance Abuse and Mental Health Services Administration's mission for the past decade. Consistent with their mission, there is a call for research and development of recovery-oriented systems of care to support affected individuals through all stages of the recovery process. Evidence is emerging to support recovery practice and research for adults, but recovery-oriented models for adolescents are scant. The Alternative Peer Group (APG) is a comprehensive adolescent recovery support model that integrates recovering peers and prosocial activities into evidence-based clinical practice. Employing APG participants' own words, this article will describe the essential elements and three theoretical frameworks underlying the APG model to illustrate how the APG serves as a developmentally appropriate recovery support service for adolescents with substance use disorder.

Combined DFT and BS study on the exchange coupling of dinuclear sandwich-type POM: comparison of different functionals and reliability of structure modeling.

PubMed

Yin, Bing; Xue, GangLin; Li, JianLi; Bai, Lu; Huang, YuanHe; Wen, ZhenYi; Jiang, ZhenYi

2012-05-01

The exchange coupling of a group of three dinuclear sandwich-type polyoxomolybdates [MM'(AsMo7O27)2](12-) with MM' = CrCr, FeFe, FeCr are theoretically predicted from combined DFT and broken-symmetry (BS) approach. Eight different XC functionals are utilized to calculate the exchange-coupling constant J from both the full crystalline structures and model structures of smaller size. The comparison between theoretical values and accurate experimental results supports the applicability of DFT-BS method in this new type of sandwich-type dinuclear polyoxomolybdates. However, a careful choice of functionals is necessary to achieve the desired accuracy. The encouraging results obtained from calculations on model structures highlight the great potential of application of structure modeling in theoretical study of POM. Structural modeling may not only reduce the computational cost of large POM species but also be able to take into account the external field effect arising from solvent molecules in solution or counterions in crystal.

Fear and Loving in Las Vegas: Evolution, Emotion, and Persuasion

PubMed Central

Griskevicius, Vladas; Goldstein, Noah J.; Mortensen, Chad R.; Sundie, Jill M.; Cialdini, Robert B.; Kenrick, Douglas T.

2009-01-01

How do arousal-inducing contexts, such as frightening or romantic television programs, influence the effectiveness of basic persuasion heuristics? Different predictions are made by three theoretical models: A general arousal model predicts that arousal should increase effectiveness of heuristics; an affective valence model predicts that effectiveness should depend on whether the context elicits positive or negative affect; an evolutionary model predicts that persuasiveness should depend on both the specific emotion that is elicited and the content of the particular heuristic. Three experiments examined how fear-inducing versus romantic contexts influenced the effectiveness of two widely used heuristics—social proof (e.g., “most popular”) and scarcity (e.g., “limited edition”). Results supported predictions from an evolutionary model, showing that fear can lead scarcity appeals to be counter-persuasive, and that romantic desire can lead social proof appeals to be counter-persuasive. The findings highlight how an evolutionary theoretical approach can lead to novel theoretical and practical marketing insights. PMID:19727416

Interpersonal suicide risk for American Indians: investigating thwarted belongingness and perceived burdensomeness.

PubMed

O'Keefe, Victoria M; Wingate, LaRicka R; Tucker, Raymond P; Rhoades-Kerswill, Sarah; Slish, Meredith L; Davidson, Collin L

2014-01-01

American Indians (AIs) experience increased suicide rates compared with other groups in the United States. However, no past studies have examined AI suicide by way of a recent empirically supported theoretical model of suicide. The current study investigated whether AI suicidal ideation can be predicted by two components: thwarted belongingness and perceived burdensomeness, from the Interpersonal-Psychological Theory of Suicide (T. E. Joiner, 2005, Why people die by suicide. Cambridge, MA: Harvard University Press). One hundred seventy-one AIs representing 27 different tribes participated in an online survey. Hierarchical regression analyses showed that perceived burdensomeness significantly predicted suicidal ideation above and beyond demographic variables and depressive symptoms; however, thwarted belongingness did not. Additionally, the two-way interaction between thwarted belongingness and perceived burdensomeness significantly predicted suicidal ideation. These results provide initial support for continued research on the components of the Interpersonal-Psychological Theory of Suicide, an empirically supported theoretical model of suicide, to predict suicidal ideation among AI populations.

Theoretical and experimental study on PMD-supported transmission using polarization diversity in coherent optical OFDM systems.

PubMed

Shieh, W; Yi, X; Ma, Y; Tang, Y

2007-08-06

In this paper, we conduct theoretical and experimental study on the PMD-supported transmission with coherent optical orthogonal frequency-division multiplexing (CO-OFDM). We first present the model for the optical fiber communication channel in the presence of the polarization effects. It shows that the optical fiber channel model can be treated as a special kind of multiple-input multiple-output (MIMO) model, namely, a two-input two-output (TITO) model which is intrinsically represented by a two-element Jones vector familiar to the optical communications community. The detailed discussions on various coherent optical MIMO-OFDM (CO-MIMO-OFDM) models are presented. Furthermore, we show the first experiment of polarization-diversity detection in CO-OFDM systems. In particular, a CO-OFDM signal at 10.7 Gb/s is successfully recovered after 900 ps differential-group-delay (DGD) and 1000-km transmission through SSMF fiber without optical dispersion compensation. The transmission experiment with higher-order PMD further confirms the immunity of the CO-OFDM signal to PMD in the transmission fiber. The nonlinearity performance of PMD-supported transmission is also reported. For the first time, nonlinear phase noise mitigation based on receiver digital signal processing is experimentally demonstrated for CO-OFDM transmission.

Brain Modules, Personality Layers, Planes of Being, Spiral Structures, and the Equally Implausible Distinction between TCI-R "Temperament" and "Character" Scales: A Reply to Cloninger.

PubMed

Farmer, Richard F; Goldberg, Lewis R

2008-09-01

In this reply we address comments by Cloninger (this issue) related to our report (Farmer & Goldberg, this issue) on the psychometric properties of the revised Temperament and Character Inventory (TCI-R) and a short inventory derivative, the TCI-140. Even though Cloninger's psychobiological model has undergone substantial theoretical modifications, the relevance of these changes for the evaluation and use of the TCI-R remains unclear. Aspects of TCI-R assessment also appear to be theoretically and empirically incongruent with Cloninger's assertion that TCI-R personality domains are non-linear and dynamic in nature. Several other core assumptions from the psychobiological model, including this most recent iteration, are non-falsifiable, inconsistently supported, or have no apparent empirical basis. Although researchers using the TCI and TCI-R have frequently accepted the temperament/character distinction and associated theoretical ramifications, for example, we find little overall support for the differentiation of TCI-R domains into these two basic categories. The implications of these observations for TCI-R assessment are briefly discussed.

Actions speak louder than words: An elaborated theoretical model of the social functions of self-injury and other harmful behaviors

PubMed Central

Nock, Matthew K.

2008-01-01

The question of why some people do things that are intentionally harmful to themselves continues to puzzle scientists, clinicians, and the public. Prior studies have demonstrated that one fairly extreme, direct form of self-harm, non-suicidal self-injury (NSSI), is maintained by both automatic (i.e., intrapersonal) as well as social (i.e., interpersonal) reinforcement. However, the majority of theoretical and empirical papers on this topic focus almost exclusively on the automatic functions. The purpose of this paper is to provide a more comprehensive analysis of the social functions of NSSI. Evidence is presented supporting the notion that NSSI is maintained by social reinforcement in at least a substantial minority of instances. Moreover, an elaborated theoretical model of the social functions of NSSI is outlined that proposes that this behavior represents a high intensity social signal used when less intense communication strategies fail (e.g., speaking, yelling, crying). The model further proposes that NSSI can serve not only as a signal of distress that is reinforced primarily by the caregiving behavior it elicits from others, but that it also can serve as a signal of strength and fitness that is reinforced by warding off potential threats (e.g., peer victimization), and in some cases can strengthen affiliation with others. Support for this theoretical model is drawn from diverse literatures including psychology, evolutionary biology, and cultural anthropology. The paper concludes with specific recommendations for empirical tests of the proposed model of the social functions of NSSI, as well as other harmful behaviors such as alcohol and drug use. PMID:19122893

Stress and wellbeing during chronic illness and partner death in later-life: the role of social support.

PubMed

Karantzas, Gery C; Gillath, Omri

2017-02-01

Chronic illness and the death of a romantic partner are two of the most significant stressors reported by older adults, resulting in various physical and mental health consequences. Evidence suggests that social support is a key factor in understanding the association between chronic illness and widowhood and the wellbeing of older adults. Nevertheless, research into social support is often approached in an atheoretical manner when investigating these stressors in older adulthood. We attempt to address this theoretical chasm by proposing an integrative model to explain social support processes in older couples which draws on models of social support and attachment theory. Our model provides an important framework for understanding existing research findings as well as guiding future research. Copyright © 2016 Elsevier Ltd. All rights reserved.

Models of consumer value cocreation in health care.

PubMed

Nambisan, Priya; Nambisan, Satish

2009-01-01

In recent years, consumer participation in health care has gained critical importance as health care organizations (HCOs) seek varied avenues to enhance the quality and the value of their offerings. Many large HCOs have established online health communities where health care consumers (patients) can interact with one another to share knowledge and offer emotional support in disease management and care. Importantly, the focus of consumer participation in health care has moved beyond such personal health care management as the potential for consumers to participate in innovation and value creation in varied areas of the health care industry becomes increasingly evident. Realizing such potential, however, will require HCOs to develop a better understanding of the varied types of consumer value cocreation that are enabled by new information and communication technologies such as online health communities and Web 2.0 (social media) technologies. This article seeks to contribute toward such an understanding by offering a concise and coherent theoretical framework to analyze consumer value cocreation in health care. We identify four alternate models of consumer value cocreation-the partnership model, the open-source model, the support-group model, and the diffusion model-and discuss their implications for HCOs. We develop our theoretical framework by drawing on theories and concepts in knowledge creation, innovation management, and online communities. A set of propositions are developed by combining theoretical insights from these areas with real-world examples of consumer value cocreation in health care. The theoretical framework offered here informs on the potential impact of the different models of consumer value cocreation on important organizational variables such as innovation cost and time, service quality, and consumer perceptions of HCO. An understanding of the four models of consumer value cocreation can help HCOs adopt appropriate strategies and practices to embrace consumers as partners in the development and delivery of innovative health care products and services.

High-Ability Students' Participation in Specialized Instructional Delivery Models: Variations by Aptitude, Grade, Gender, and Content Area

ERIC Educational Resources Information Center

Assouline, Susan G.; Colangelo, Nicholas; Heo, Nanseol; Dockery, Lori

2013-01-01

Established in the early 1970s, the talent search model has garnered strong theoretical and programming support for addressing the academic needs of highly able students. The two main components of the talent search model are discovery (identification) and development (programming) of academic talent. Discovery of academically talented elementary…

Gagne's and Laurillard's Models of Instruction Applied to Distance Education: A Theoretically Driven Evaluation of an Online Curriculum in Public Health.

ERIC Educational Resources Information Center

Hannon, Peggy; Umble, Karl E.; Alexander, Lorraine; Francisco, Don; Steckler, Allan; Tudor, Gai; Upshaw, Vaughn

2002-01-01

Student evaluations of an online public health curriculum developed using the instructional models of Gagne and Laurillard indicated that students were generally satisfied with the experience. However, some dissatisfaction with the feedback and guidance they received supported Laurillard's model. Comments revealed an aspect of the learning…

The Model Method: Singapore Children's Tool for Representing and Solving Algebraic Word Problems

ERIC Educational Resources Information Center

Ng, Swee Fong; Lee, Kerry

2009-01-01

Solving arithmetic and algebraic word problems is a key component of the Singapore elementary mathematics curriculum. One heuristic taught, the model method, involves drawing a diagram to represent key information in the problem. We describe the model method and a three-phase theoretical framework supporting its use. We conducted 2 studies to…

Social Context, Self-Perceptions and Student Engagement: A SEM Investigation of the Self-System Model of Motivational Development (SSMMD)

ERIC Educational Resources Information Center

Dupont, Serge; Galand, Benoit; Nils, Frédéric; Hospel, Virginie

2014-01-01

Introduction: The present study aimed to test a theoretically-based model (the self-system model of motivational development) including at the same time the extent to which the social context provides structure, warmth and autonomy support, the students' perceived autonomy, relatedness and competence, and behavioral, cognitive and emotional…

The "New Family" Model: The Evolution of Group Treatment for Adult Survivors of Childhood Sexual Abuse.

ERIC Educational Resources Information Center

Kriedler, Maryhelen C.; Fluharty, Leslie Barnes

1994-01-01

Discusses the evolution of a group therapy protocol for adult survivors of incest and the theoretical model on which it is based, the learned helplessness model of depression. Learned helplessness theory supports the assumption that victims internalize trauma. Group activities were aimed at changing negative self-beliefs and at providing…

Factors Influencing the Performance of Dynamic Decision Network for INQPRO

ERIC Educational Resources Information Center

Ting, Choo-Yee; Phon-Amnuaisuk, Somnuk

2009-01-01

There has been an increasing interest in employing decision-theoretic framework for learner modeling and provision of pedagogical support in Intelligent Tutoring Systems (ITSs). Much of the existing learner modeling research work focuses on identifying appropriate learner properties. Little attention, however, has been given to leverage Dynamic…

Collaboration and Self-Regulation in Teachers' Professional Development

ERIC Educational Resources Information Center

Butler, Deborah L.; Lauscher, Helen Novak; Jarvis-Selinger, Sandra; Beckingham, Beverly

2004-01-01

This paper describes a professional development model with promise for supporting meaningful shifts in practice. We begin by introducing the theoretical principles underlying our professional development model, with a focus on explicating the interface between collaborative inquiry in a learning community (Lave, 1991, In L.B. Resnick, J.M. Levine,…

What Unites Us All: Establishing Special Education Teacher Education Universals

ERIC Educational Resources Information Center

Darling, Sharon M.; Dukes, Charles; Hall, Kalynn

2016-01-01

The theoretical base that supports human universals served as a model for proposing special education teacher education universals. The human universals model is explained and put forth as a basis for identifying special education teacher education universals. Twenty-four English language journals from different countries representing four…

Solutions of burnt-bridge models for molecular motor transport.

PubMed

Morozov, Alexander Yu; Pronina, Ekaterina; Kolomeisky, Anatoly B; Artyomov, Maxim N

2007-03-01

Transport of molecular motors, stimulated by interactions with specific links between consecutive binding sites (called "bridges"), is investigated theoretically by analyzing discrete-state stochastic "burnt-bridge" models. When an unbiased diffusing particle crosses the bridge, the link can be destroyed ("burned") with a probability p , creating a biased directed motion for the particle. It is shown that for probability of burning p=1 the system can be mapped into a one-dimensional single-particle hopping model along the periodic infinite lattice that allows one to calculate exactly all dynamic properties. For the general case of p<1 a theoretical method is developed and dynamic properties are computed explicitly. Discrete-time and continuous-time dynamics for periodic distribution of bridges and different burning dynamics are analyzed and compared. Analytical predictions are supported by extensive Monte Carlo computer simulations. Theoretical results are applied for analysis of the experiments on collagenase motor proteins.

Solutions of burnt-bridge models for molecular motor transport

NASA Astrophysics Data System (ADS)

Morozov, Alexander Yu.; Pronina, Ekaterina; Kolomeisky, Anatoly B.; Artyomov, Maxim N.

2007-03-01

Transport of molecular motors, stimulated by interactions with specific links between consecutive binding sites (called “bridges”), is investigated theoretically by analyzing discrete-state stochastic “burnt-bridge” models. When an unbiased diffusing particle crosses the bridge, the link can be destroyed (“burned”) with a probability p , creating a biased directed motion for the particle. It is shown that for probability of burning p=1 the system can be mapped into a one-dimensional single-particle hopping model along the periodic infinite lattice that allows one to calculate exactly all dynamic properties. For the general case of p<1 a theoretical method is developed and dynamic properties are computed explicitly. Discrete-time and continuous-time dynamics for periodic distribution of bridges and different burning dynamics are analyzed and compared. Analytical predictions are supported by extensive Monte Carlo computer simulations. Theoretical results are applied for analysis of the experiments on collagenase motor proteins.

Evidence accumulation as a model for lexical selection.

PubMed

Anders, R; Riès, S; van Maanen, L; Alario, F X

2015-11-01

We propose and demonstrate evidence accumulation as a plausible theoretical and/or empirical model for the lexical selection process of lexical retrieval. A number of current psycholinguistic theories consider lexical selection as a process related to selecting a lexical target from a number of alternatives, which each have varying activations (or signal supports), that are largely resultant of an initial stimulus recognition. We thoroughly present a case for how such a process may be theoretically explained by the evidence accumulation paradigm, and we demonstrate how this paradigm can be directly related or combined with conventional psycholinguistic theory and their simulatory instantiations (generally, neural network models). Then with a demonstrative application on a large new real data set, we establish how the empirical evidence accumulation approach is able to provide parameter results that are informative to leading psycholinguistic theory, and that motivate future theoretical development. Copyright © 2015 Elsevier Inc. All rights reserved.

Interpersonal Emotion Regulation Model of Mood and Anxiety Disorders.

PubMed

Hofmann, Stefan G

2014-10-01

Although social factors are of critical importance in the development and maintenance of emotional disorders, the contemporary view of emotion regulation has been primarily limited to intrapersonal processes. Based on diverse perspectives pointing to the communicative function of emotions, the social processes in self-regulation, and the role of social support, this article presents an interpersonal model of emotion regulation of mood and anxiety disorders. This model provides a theoretical framework to understand and explain how mood and anxiety disorders are regulated and maintained through others. The literature, which provides support for the model, is reviewed and the clinical implications are discussed.

Matching Social Support and Sources of Stress in Female Nursing Faculty Pursuing Doctoral Study.

ERIC Educational Resources Information Center

Kenty, Janet R.

This study surveyed 111 women faculty in four-year nursing education programs who were also enrolled in doctoral study to determine the stresses involved in balancing the two roles of teacher and student. The theoretical framework was an extension of Cutrona and Russell's social support model which proposes that stressful life events impact…

Examining the Digital Divide in K-12 Public Schools: Four-Year Trends for Supporting ICT Literacy in Florida

ERIC Educational Resources Information Center

Hohlfeld, Tina N.; Ritzhaupt, Albert D.; Barron, Ann E.; Kemker, Kate

2008-01-01

While there is evidence that access to computers in schools has increased, there remain questions about whether low socio-economic status (SES) schools provide students with equitable supports for achieving information communication technology (ICT) literacy. This research first presents a theoretical model to examine the digital divide within…

The isotropic local Wigner-Seitz model: An accurate theoretical model for the quasi-free electron energy in fluids

NASA Astrophysics Data System (ADS)

Evans, Cherice; Findley, Gary L.

The quasi-free electron energy V0 (ρ) is important in understanding electron transport through a fluid, as well as for modeling electron attachment reactions in fluids. Our group has developed an isotropic local Wigner-Seitz model that allows one to successfully calculate the quasi-free electron energy for a variety of atomic and molecular fluids from low density to the density of the triple point liquid with only a single adjustable parameter. This model, when coupled with the quasi-free electron energy data and the thermodynamic data for the fluids, also can yield optimized intermolecular potential parameters and the zero kinetic energy electron scattering length. In this poster, we give a review of the isotropic local Wigner-Seitz model in comparison to previous theoretical models for the quasi-free electron energy. All measurements were performed at the University of Wisconsin Synchrotron Radiation Center. This work was supported by a Grants from the National Science Foundation (NSF CHE-0956719), the Petroleum Research Fund (45728-B6 and 5-24880), the Louisiana Board of Regents Support Fund (LEQSF(2006-09)-RD-A33), and the Professional Staff Congress City University of New York.

Suicide prevention by online support groups: an action theory-based model of emotional first aid.

PubMed

Gilat, Itzhak; Shahar, Golan

2009-01-01

In the last two decades, online support groups have become a valuable source of help for individuals in suicidal crisis. Their attractiveness is attributed to features that enhance help-seeking and self-disclosure such as availability, anonymity, and use of written communication. However, online support groups also suffer from limitations and potential risks as agents of suicide prevention. The Israeli Association for Emotional First Aid (ERAN) has developed a practical model that seeks to maximize the benefits and minimize the risks of online suicide prevention. The model applies the Action Theory concepts whereby individuals shape their own environment. The present paper presents the model, which is based on an online support group combined with personal chat and a telephonic help line. The online support group is moderated by paraprofessionals who function as both process regulators and support providers. The principles and practice of the model are described, the theoretical rationale is presented, and directions for future research are suggested.

Nuclear clustering and the electron screening puzzle

NASA Astrophysics Data System (ADS)

Bertulani, C. A.; Spitaleri, C.

2018-01-01

Electron screening changes appreciably the magnitude of astrophysical nuclear reactions within stars. This effect is also observed in laboratory experiments on Earth, where atomic electrons are present in the nuclear targets. Theoretical models were developed over the past 30 years and experimental measurements have been carried out to study electron screening in thermonuclear reactions. None of the theoretical models were able to explain the high values of the experimentally determined screening potentials. We explore the possibility that the "electron screening puzzle" is due to nuclear clusterization and polarization e_ects in the fusion reactions. We will discuss the supporting arguments for this scenario.

On the road to metallic nanoparticles by rational design: bridging the gap between atomic-level theoretical modeling and reality by total scattering experiments

NASA Astrophysics Data System (ADS)

Prasai, Binay; Wilson, A. R.; Wiley, B. J.; Ren, Y.; Petkov, Valeri

2015-10-01

The extent to which current theoretical modeling alone can reveal real-world metallic nanoparticles (NPs) at the atomic level was scrutinized and demonstrated to be insufficient and how it can be improved by using a pragmatic approach involving straightforward experiments is shown. In particular, 4 to 6 nm in size silica supported Au100-xPdx (x = 30, 46 and 58) explored for catalytic applications is characterized structurally by total scattering experiments including high-energy synchrotron X-ray diffraction (XRD) coupled to atomic pair distribution function (PDF) analysis. Atomic-level models for the NPs are built by molecular dynamics simulations based on the archetypal for current theoretical modeling Sutton-Chen (SC) method. Models are matched against independent experimental data and are demonstrated to be inaccurate unless their theoretical foundation, i.e. the SC method, is supplemented with basic yet crucial information on the length and strength of metal-to-metal bonds and, when necessary, structural disorder in the actual NPs studied. An atomic PDF-based approach for accessing such information and implementing it in theoretical modeling is put forward. For completeness, the approach is concisely demonstrated on 15 nm in size water-dispersed Au particles explored for bio-medical applications and 16 nm in size hexane-dispersed Fe48Pd52 particles explored for magnetic applications as well. It is argued that when ``tuned up'' against experiments relevant to metals and alloys confined to nanoscale dimensions, such as total scattering coupled to atomic PDF analysis, rather than by mere intuition and/or against data for the respective solids, atomic-level theoretical modeling can provide a sound understanding of the synthesis-structure-property relationships in real-world metallic NPs. Ultimately this can help advance nanoscience and technology a step closer to producing metallic NPs by rational design.The extent to which current theoretical modeling alone can reveal real-world metallic nanoparticles (NPs) at the atomic level was scrutinized and demonstrated to be insufficient and how it can be improved by using a pragmatic approach involving straightforward experiments is shown. In particular, 4 to 6 nm in size silica supported Au100-xPdx (x = 30, 46 and 58) explored for catalytic applications is characterized structurally by total scattering experiments including high-energy synchrotron X-ray diffraction (XRD) coupled to atomic pair distribution function (PDF) analysis. Atomic-level models for the NPs are built by molecular dynamics simulations based on the archetypal for current theoretical modeling Sutton-Chen (SC) method. Models are matched against independent experimental data and are demonstrated to be inaccurate unless their theoretical foundation, i.e. the SC method, is supplemented with basic yet crucial information on the length and strength of metal-to-metal bonds and, when necessary, structural disorder in the actual NPs studied. An atomic PDF-based approach for accessing such information and implementing it in theoretical modeling is put forward. For completeness, the approach is concisely demonstrated on 15 nm in size water-dispersed Au particles explored for bio-medical applications and 16 nm in size hexane-dispersed Fe48Pd52 particles explored for magnetic applications as well. It is argued that when ``tuned up'' against experiments relevant to metals and alloys confined to nanoscale dimensions, such as total scattering coupled to atomic PDF analysis, rather than by mere intuition and/or against data for the respective solids, atomic-level theoretical modeling can provide a sound understanding of the synthesis-structure-property relationships in real-world metallic NPs. Ultimately this can help advance nanoscience and technology a step closer to producing metallic NPs by rational design. Electronic supplementary information (ESI) available: XRD patterns, TEM and 3D structure modelling methodology. See DOI: 10.1039/c5nr04678e

Self-Assembled Magnetic Surface Swimmers: Theoretical Model

NASA Astrophysics Data System (ADS)

Aranson, Igor; Belkin, Maxim; Snezhko, Alexey

2009-03-01

The mechanisms of self-propulsion of living microorganisms are a fascinating phenomenon attracting enormous attention in the physics community. A new type of self-assembled micro-swimmers, magnetic snakes, is an excellent tool to model locomotion in a simple table-top experiment. The snakes self-assemble from a dispersion of magnetic microparticles suspended on the liquid-air interface and subjected to an alternating magnetic field. Formation and dynamics of these swimmers are captured in the framework of theoretical model coupling paradigm equation for the amplitude of surface waves, conservation law for the density of particles, and the Navier-Stokes equation for hydrodynamic flows. The results of continuum modeling are supported by hybrid molecular dynamics simulations of magnetic particles floating on the surface of fluid.

Disentangling Gratitude: A Theoretical and Psychometric Examination of the Gratitude Resentment and Appreciation Test-Revised Short (GRAT-RS).

PubMed

Hammer, Joseph H; Brenner, Rachel E

2017-07-14

This study extended our theoretical and applied understanding of gratitude through a psychometric examination of the most popular multidimensional measure of gratitude, the Gratitude, Resentment, and Appreciation Test-Revised Short form (GRAT-RS). Namely, the dimensionality of the GRAT-RS, the model-based reliability of the GRAT-RS total score and 3 subscale scores, and the incremental evidence of validity for its latent factors were assessed. Dimensionality measures (e.g., explained common variance) and confirmatory factor analysis results with 426 community adults indicated that the GRAT-RS conformed to a multidimensional (bifactor) structure. Model-based reliability measures (e.g., omega hierarchical) provided support for the future use of the Lack of a Sense of Deprivation raw subscale score, but not for the raw GRAT-RS total score, Simple Appreciation subscale score, or Appreciation of Others subscale score. Structural equation modeling results indicated that only the general gratitude factor and the lack of a sense of deprivation specific factor accounted for significant variance in life satisfaction, positive affect, and distress. These findings support the 3 pillars of gratitude conceptualization of gratitude over competing conceptualizations, the position that the specific forms of gratitude are theoretically distinct, and the argument that appreciation is distinct from the superordinate construct of gratitude.

Theoretical modeling of critical temperature increase in metamaterial superconductors

NASA Astrophysics Data System (ADS)

Smolyaninov, Igor; Smolyaninova, Vera

Recent experiments have demonstrated that the metamaterial approach is capable of drastic increase of the critical temperature Tc of epsilon near zero (ENZ) metamaterial superconductors. For example, tripling of the critical temperature has been observed in Al-Al2O3 ENZ core-shell metamaterials. Here, we perform theoretical modelling of Tc increase in metamaterial superconductors based on the Maxwell-Garnett approximation of their dielectric response function. Good agreement is demonstrated between theoretical modelling and experimental results in both aluminum and tin-based metamaterials. Taking advantage of the demonstrated success of this model, the critical temperature of hypothetic niobium, MgB2 and H2S-based metamaterial superconductors is evaluated. The MgB2-based metamaterial superconductors are projected to reach the liquid nitrogen temperature range. In the case of an H2S-based metamaterial Tc appears to reach 250 K. This work was supported in part by NSF Grant DMR-1104676 and the School of Emerging Technologies at Towson University.

ADHD bifactor model based on parent and teacher ratings of Malaysian children.

PubMed

Gomez, Rapson

2014-04-01

The study used confirmatory factor analysis to ascertain support for the bifactor model of the Attention Deficit/Hyperactivity Disorder (ADHD) symptoms, based on parent and teacher ratings for a group of Malaysian children. Malaysian parents and teachers completed ratings of ADHD and Opposition Defiant Disorder (ODD) symptoms for 934 children. For both sets of ratings, the findings indicating good fit for the bifactor model, and the factors in this model showed differential associations with ODD, thereby supporting the internal and external validity of this model. The theoretical and clinical implications of the findings are discussed. Copyright © 2013 Elsevier B.V. All rights reserved.

Examining Mutual Elements of the Job Strain Model and the Effort--Reward Imbalance Model among Special Education Staff in the USA

ERIC Educational Resources Information Center

Shyman, Eric

2011-01-01

Two theories of occupational stress are often cited as being most supported by research: the job strain model (JSM) and the effort--reward imbalance model (ERIM). In order to investigate the applicability of mutual theoretical elements of both models to special education in the USA, a sample of 100 special education paraeducators in public and…

Psychological and behavioral consequences of job loss: a covariance structure analysis using Weiner's (1985) attribution model.

PubMed

Prussia, G E; Kinicki, A J; Bracker, J S

1993-06-01

B. Weiner's (1985) attribution model of achievement motivation and emotion was used as a theoretical foundation to examine the mediating processes between involuntary job loss and employment status. Seventy-nine manufacturing employees were surveyed 1 month prior to permanent displacement, and finding another job was assessed 18 months later. Covariance structure analysis was used to evaluate goodness of fit and to compare the model to alternative measurement and structural representations. Discriminant validity analyses indicated that the causal dimensions underlying the model were not independent. Model predictions were supported in that internal and stable attributions for job loss negatively influenced finding another job through expectations for re-employment. These predictions held up even after controlling for influential unmeasured variables. Practical and theoretical implications are discussed.

A Conceptual Model for Increasing Use of Electronic Medical Records by Primary Care Physicians Through End-User Support.

PubMed

Randhawa, Gurprit K

2017-01-01

A conceptual model for exploring the relationship between end-user support (EUS) and electronic medical record (EMR) use by primary care physicians is presented. The model was developed following a review of conceptual and theoretical frameworks related to technology adoption/use and EUS. The model includes (a) one core construct (facilitating conditions), (b) four antecedents and one postcedent of facilitating conditions, and (c) four moderators. EMR use behaviour is the key outcome of the model. The proposed conceptual model should be tested. The model may be used to inform planning and decision-making for EMR implementations to increase EMR use for benefits realization.

Determinants of self-reported bystander behavior in cyberbullying incidents amongst adolescents.

PubMed

DeSmet, Ann; Veldeman, Charlene; Poels, Karolien; Bastiaensens, Sara; Van Cleemput, Katrien; Vandebosch, Heidi; De Bourdeaudhuij, Ilse

2014-04-01

This study explores behavioral determinants of self-reported cyberbullying bystander behavior from a behavioral change theoretical perspective, to provide levers for interventions. Nine focus groups were conducted with 61 young adolescents (aged 12-16 years, 52% girls). Assertive defending, reporting to others, providing advice, and seeking support were the most mentioned behaviors. Self-reported bystander behavior heavily depended on contextual factors, and should not be considered a fixed participant role. Bystanders preferred to handle cyberbullying offline and in person, and comforting the victim was considered more feasible than facing the bully. Most prevailing behavioral determinants to defend or support the victim were low moral disengagement, that the victim is an ingroup member, and that the bystander is popular. Youngsters felt they received little encouragement from their environment to perform positive bystanding behavior, since peers have a high acceptance for not defending and perceived parental support for defending behavior is largely lacking. These results suggest multilevel models for cyberbullying research, and interventions are needed. With much previous research into cyberbullying insufficiently founded in theoretical models, the employed framework of the Integrative Model and Social Cognitive Theory may inspire future studies into bystander behavior.

Validating the Learning Cycle Models of Business Simulation Games via Student Perceived Gains in Skills and Knowledge

ERIC Educational Resources Information Center

Tao, Yu-Hui; Yeh, C. Rosa; Hung, Kung Chin

2015-01-01

Several theoretical models have been constructed to determine the effects of buisness simulation games (BSGs) on learning performance. Although these models agree on the concept of learning-cycle effect, no empirical evidence supports the claim that the use of learning cycle activities with BSGs produces an effect on incremental gains in knowledge…

An Evaluation of a Theoretical Model Predicting Dieting Behaviors: Tests of Measurement and Structural Invariance across Ethnicity and Gender

ERIC Educational Resources Information Center

Boie, Ioana; Lopez, Anna L.; Sass, Daniel A.

2013-01-01

This study evaluated a model linking internalization and dieting behaviors in a sample ("n" = 499) of Latina/o and White college students. Analyses revealed that the scales were invariant across ethnic and gender groups and generally supported the invariance of the proposed model across these groups. Analyses also revealed no ethnic mean…

Assessing Intelligence in Children and Youth Living in the Netherlands

ERIC Educational Resources Information Center

Hurks, Petra P. M.; Bakker, Helen

2016-01-01

In this article, we briefly describe the history of intelligence test use with children and youth in the Netherlands, explain which models of intelligence guide decisions about test use, and detail how intelligence tests are currently being used in Dutch school settings. Empirically supported and theoretical models studying the structure of human…

The Development and Testing of a Tool for Analysis of Computer-Mediated Conferencing Transcripts.

ERIC Educational Resources Information Center

Fahy, Patrick J.; Crawford, Gail; Ally, Mohamed; Cookson, Peter; Keller, Verna; Prosser, Frank

2000-01-01

The Zhu model for analyzing computer mediated communications was further developed by an Athabasca University (Alberta) distance education research team based on ease of use, reliability, validity, theoretical support, and cross-discipline utility. Five classification categories of the new model are vertical questioning, horizontal questioning,…

Social-Emotional Development, School Readiness, Teacher-Child Interactions, and Classroom Environment

ERIC Educational Resources Information Center

Heller, Sherryl Scott; Rice, Janet; Boothe, Allison; Sidell, Margo; Vaughn, Krystal; Keyes, Angela; Nagle, Geoffrey

2012-01-01

This article investigates the effectiveness of a statewide 6-month early childhood mental health consultation (ECMHC) model on teachers' emotional support of children and classroom organization. We provide a brief historical and theoretical background of the field of ECMHC, present the logic model for our ECMHC intervention, and discuss the…

Aging and financial planning for retirement: interdisciplinary influences viewed through a cross-cultural lens.

PubMed

Hershey, Douglas A; Henkens, Kene; Van Dalen, Hendrik P

2010-01-01

Current theoretical models support the existence of interactions between the individual and socio-environmental forces when it comes to the formation and enactment of life plans (Friedman & Scholnick, 1997; Shanahan & Elder, 2002). In this investigation, we examine the social, economic, and psychological forces that impact financial planning for retirement. The collective force of these three broad sets of influences was examined from developmental and cross-cultural perspectives, among respondents from two countries with very different retirement financing systems. Participants were 419 American and 556 Dutch working adults, 25-64 years of age. Path analysis models were created to examine differences in planning associated with age and national origin. Compared to younger individuals, older respondents in both countries were more involved in nearly all aspects of the financial planning process. Differences across cultures were also observed in the social support mechanisms that underlie planning and the impact economic forces have on perceptions of saving adequacy. The discussion focuses on the value of developing interdisciplinary theoretical models of planning, and how such models can inform the development of savings-oriented intervention and public policy initiatives.

Stereotype Threat and College Academic Performance: A Latent Variables Approach*

PubMed Central

Owens, Jayanti; Massey, Douglas S.

2013-01-01

Stereotype threat theory has gained experimental and survey-based support in helping explain the academic underperformance of minority students at selective colleges and universities. Stereotype threat theory states that minority students underperform because of pressures created by negative stereotypes about their racial group. Past survey-based studies, however, are characterized by methodological inefficiencies and potential biases: key theoretical constructs have only been measured using summed indicators and predicted relationships modeled using ordinary least squares. Using the National Longitudinal Survey of Freshman, this study overcomes previous methodological shortcomings by developing a latent construct model of stereotype threat. Theoretical constructs and equations are estimated simultaneously from multiple indicators, yielding a more reliable, valid, and parsimonious test of key propositions. Findings additionally support the view that social stigma can indeed have strong negative effects on the academic performance of pejoratively stereotyped racial-minority group members, not only in laboratory settings, but also in the real world. PMID:23950616

Social support and vulnerability: state of the art in relation to families and children.

PubMed

MacElveen-Hoehn, P; Eyres, S J

1984-01-01

The purpose of this presentation is to review the concepts of social support and vulnerable families and children, propose a theoretical model on coping and adaptation, and ascertain any significant implications for the delivery of health care services and future research. The review of the literature indicates that major problems persist in the classification, conceptualization, empirical investigation, and clinical application of social support due to a lack of clarity regarding the definition of social support and how it works. Related perspectives such as bonding, child development, and child rearing also reaffirm the need for and the utilization of social support. High-risk factors, such as low maternal age, poverty, single parenthood, and long-term health problems, increase the vulnerability of families and children. This literature strongly suggests that the interactions of adults and children with supportive members of their social networks are important in the development of essential cognitive and social skills, as well as for the promotion of security and comfort. Supports from individuals, families, and groups also are associated with more successful adaptation and favorable outcomes. Despite numerous articles and research projects, however, questions concerning how social support works to assist vulnerable children and families remain. Seven factors are proposed as a theoretical model to identify threatening situations and coping difficulties so that appropriate support can be provided. These factors are surprise, experience, confusion, perceived effectiveness, perceived allies, perceived uniqueness of threat, and overload. Additional testing is required for this model so that a more meaningful investigation and utilization of social support can be established. Additional research also is indicated to determine the specific types of support needed in the presence of certain factors, network style preferences, the supply and demand for support over the life span, and cultural aspects of coping and support processes. The position that appropriate social support will promote mastery and self-determination has significant implications for health professionals.

Program Support and Value of Training in Mentors' Satisfaction and Anticipated Continuation of School-Based Mentoring Relationships

ERIC Educational Resources Information Center

McQuillin, Samuel D.; Straight, Gerald G.; Saeki, Elina

2015-01-01

In this study, we tested a theoretical model of training practices in school-based mentoring by comparing the differences between two mentoring programs on mentor-reported program support, value of training, relationship satisfaction, and plans to continue mentoring. The two mentoring programs that we compared were conducted at the same school and…

Domains of Quality of Life of People with Profound Multiple Disabilities: The Perspective of Parents and Direct Support Staff

ERIC Educational Resources Information Center

Petry, Katja; Maes, Bea; Vlaskamp, Carla

2005-01-01

Background: This study considered the general validity of the basic domains of quality of life that appear in theoretical models, in relation to people with profound multiple disabilities. The authors examined how parents and direct support staff operationalized these basic domains for people with profound multiple disabilities. They investigated…

Income Inequality, the Median Voter, and the Support for Public Education. NBER Working Paper No. 16097

ERIC Educational Resources Information Center

Corcoran, Sean; Evans, William N.

2010-01-01

Using a panel of U.S. school districts spanning 1970-2000, we examine the relationship between income inequality and fiscal support for public education. In contrast with recent theoretical and empirical work suggesting a negative relationship between inequality and public spending, we find results consistent with a median voter model, in which…

Magnetohydrodynamic Particle Acceleration Processes: SSX Experiments, Theory, and Astrophysical Applications

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

Brown, Michael R.

2006-11-16

Project Title: Magnetohydrodynamic Particle Acceleration Processes: SSX Experiments, Theory, and Astrophysical Applications PI: Michael R. Brown, Swarthmore College The purpose of the project was to provide theoretical and modeling support to the Swarthmore Spheromak Experiment (SSX). Accordingly, the theoretical effort was tightly integrated into the SSX experimental effort. During the grant period, Michael Brown and his experimental collaborators at Swarthmore, with assistance from W. Matthaeus as appropriate, made substantial progress in understanding the physics SSX plasmas.

Making sense of shared sense-making in an inquiry-based science classroom: Toward a sociocultural theory of mind

NASA Astrophysics Data System (ADS)

Ladewski, Barbara G.

Despite considerable exploration of inquiry and reflection in the literatures of science education and teacher education/teacher professional development over the past century, few theoretical or analytical tools exist to characterize these processes within a naturalistic classroom context. In addition, little is known regarding possible developmental trajectories for inquiry or reflection---for teachers or students---as these processes develop within a classroom context over time. In the dissertation, I use a sociocultural lens to explore these issues with an eye to the ways in which teachers and students develop shared sense-making, rather than from the more traditional perspective of individual teacher activity or student learning. The study includes both theoretical and empirical components. Theoretically, I explore the elaborations of sociocultural theory needed to characterize teacher-student shared sense-making as it develops within a classroom context, and, in particular, the role of inquiry and reflection in that sense-making. I develop a sociocultural model of shared sense-making that attempts to represent the dialectic between the individual and the social, through an elaboration of existing sociocultural and psychological constructs, including Vygotsky's zone of proximal development and theory of mind. Using this model as an interpretive framework, I develop a case study that explores teacher-student shared sense-making within a middle-school science classroom across a year of scaffolded introduction to inquiry-based science instruction. The empirical study serves not only as a test case for the theoretical model, but also informs our understanding regarding possible developmental trajectories and important mechanisms supporting and constraining shared sense-making within inquiry-based science classrooms. Theoretical and empirical findings provide support for the idea that perspectival shifts---that is, shifts of point-of-view that alter relationships and proximities of elements within the interaction space---play an important role in shared sense-making. Findings further suggest that the mutually constitutive interaction of inquiry and reflection plays a key role in flexible shared sense-making. Finally, findings lend support to the idea of a dialectical relationship between human models of shared sense-making and human systems of shared sense-making; that is, the ways in which human minds are coordinated is a work in progress, shaping and shaped by human culture.

Interpersonal Emotion Regulation Model of Mood and Anxiety Disorders

PubMed Central

Hofmann, Stefan G.

2014-01-01

Although social factors are of critical importance in the development and maintenance of emotional disorders, the contemporary view of emotion regulation has been primarily limited to intrapersonal processes. Based on diverse perspectives pointing to the communicative function of emotions, the social processes in self-regulation, and the role of social support, this article presents an interpersonal model of emotion regulation of mood and anxiety disorders. This model provides a theoretical framework to understand and explain how mood and anxiety disorders are regulated and maintained through others. The literature, which provides support for the model, is reviewed and the clinical implications are discussed. PMID:25267867

Validation of theoretical pathway between discrimination, diabetes self-care and glycemic control.

PubMed

Dawson, Aprill Z; Walker, Rebekah J; Campbell, Jennifer A; Egede, Leonard E

2016-07-01

This study examined the mechanisms through which discrimination influences diabetes self-care and glycemic control in patients with diabetes by using structured equation modeling. 615 patients were recruited from two adult primary care clinics in the southeastern United States. Measures were based on a theoretical model and included perceived discrimination, social support, social cohesion, and perceived stress. Structured equation modeling examined the relationship with diabetes self-care and glycemic control. The final model (chi2(211)=328.82, p<0.0001, R(2)=0.99, RMSEA=0.03 and CFI=0.98) shows that higher stress is directly significantly related to a decreased self-care (r=-0.59, p <0.001) and increased HbA1c (r=0.27, p<0.05). There was no significant direct association between discrimination, social support or social cohesion, and glycemic control or self-care. There was, however, a direct significant association between increased discrimination (r=0.46, p<0.001), decreased social support (r=-0.34, p<0.001), increased social cohesion (r=0.14, p<0.05) and increased stress. These results support the hypothesized pathway of discrimination on health outcomes, showing both a direct and indirect influence through stress on HbA1c in adults with diabetes. Understanding the pathways through which discrimination influences diabetes outcomes is important for providing more comprehensive and effective care. These results suggest future interventions targeting patients with diabetes should take discrimination-induced stress into account. Copyright © 2016 Elsevier Inc. All rights reserved.

Engaging Students In Modeling Instruction for Introductory Physics

NASA Astrophysics Data System (ADS)

Brewe, Eric

2016-05-01

Teaching introductory physics is arguably one of the most important things that a physics department does. It is the primary way that students from other science disciplines engage with physics and it is the introduction to physics for majors. Modeling instruction is an active learning strategy for introductory physics built on the premise that science proceeds through the iterative process of model construction, development, deployment, and revision. We describe the role that participating in authentic modeling has in learning and then explore how students engage in this process in the classroom. In this presentation, we provide a theoretical background on models and modeling and describe how these theoretical elements are enacted in the introductory university physics classroom. We provide both quantitative and video data to link the development of a conceptual model to the design of the learning environment and to student outcomes. This work is supported in part by DUE #1140706.

Tier 2 Intervention for At-Risk First-Grade Students within a Response-to-Intervention Model of Support

ERIC Educational Resources Information Center

Bryant, Diane Pedrotty

2014-01-01

Clarke et al. (2014) provide a persuasive case for the role of a theory-of-change model to guide the nature of curriculum development work embodying both a theoretical and empirical knowledge foundation. They illuminate the components of their model, which were used to design and test the efficacy of a Tier 2 intervention for students who met…

Teacher Efficacy in Student Engagement, Instructional Management, Student Stressors, and Burnout: A Theoretical Model Using In-Class Variables to Predict Teachers' Intent-to-Leave

ERIC Educational Resources Information Center

Martin, Nancy K.; Sass, Daniel A.; Schmitt, Thomas A.

2012-01-01

The models presented here posit a complex relationship between efficacy in student engagement and intent-to-leave that is mediated by in-class variables of instructional management, student behavior stressors, aspects of burnout, and job satisfaction. Using data collected from 631 teachers, analyses provided support for the two models that…

Research on the thickness control method of workbench oil film based on theoretical model

NASA Astrophysics Data System (ADS)

Pei, Tang; Lin, Lin; Liu, Ge; Yu, Liping; Xu, Zhen; Zhao, Di

2018-06-01

To improve the thickness adjustability of the workbench oil film, we designed a software system to control the thickness of oil film based on the Siemens 840dsl CNC system and set up an experimental platform. A regulation scheme of oil film thickness based on theoretical model is proposed, the accuracy and feasibility of which is proved by experiment results. It's verified that the method mentioned above can meet the demands of workbench oil film thickness control, the experiment is simple and efficient with high control precision. Reliable theory support is supplied for the development of workbench oil film active control system as well.

Stellar granulation as seen in disk-integrated intensity. II. Theoretical scaling relations compared with observations

NASA Astrophysics Data System (ADS)

Samadi, R.; Belkacem, K.; Ludwig, H.-G.; Caffau, E.; Campante, T. L.; Davies, G. R.; Kallinger, T.; Lund, M. N.; Mosser, B.; Baglin, A.; Mathur, S.; Garcia, R. A.

2013-11-01

Context. A large set of stars observed by CoRoT and Kepler shows clear evidence for the presence of a stellar background, which is interpreted to arise from surface convection, i.e., granulation. These observations show that the characteristic time-scale (τeff) and the root-mean-square (rms) brightness fluctuations (σ) associated with the granulation scale as a function of the peak frequency (νmax) of the solar-like oscillations. Aims: We aim at providing a theoretical background to the observed scaling relations based on a model developed in Paper I. Methods: We computed for each 3D model the theoretical power density spectrum (PDS) associated with the granulation as seen in disk-integrated intensity on the basis of the theoretical model published in Paper I. For each PDS we derived the associated characteristic time (τeff) and the rms brightness fluctuations (σ) and compared these theoretical values with the theoretical scaling relations derived from the theoretical model and the measurements made on a large set of Kepler targets. Results: We derive theoretical scaling relations for τeff and σ, which show the same dependence on νmax as the observed scaling relations. In addition, we show that these quantities also scale as a function of the turbulent Mach number (ℳa) estimated at the photosphere. The theoretical scaling relations for τeff and σ match the observations well on a global scale. Quantitatively, the remaining discrepancies with the observations are found to be much smaller than previous theoretical calculations made for red giants. Conclusions: Our modelling provides additional theoretical support for the observed variations of σ and τeff with νmax. It also highlights the important role of ℳa in controlling the properties of the stellar granulation. However, the observations made with Kepler on a wide variety of stars cannot confirm the dependence of our scaling relations on ℳa. Measurements of the granulation background and detections of solar-like oscillations in a statistically sufficient number of cool dwarf stars will be required for confirming the dependence of the theoretical scaling relations with ℳa. Appendices are available in electronic form at http://www.aanda.org

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

PubMed

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

2018-07-01

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

An integrated model of academic self-concept development: Academic self-concept, grades, test scores, and tracking over 6 years.

PubMed

Marsh, Herbert W; Pekrun, Reinhard; Murayama, Kou; Arens, A Katrin; Parker, Philip D; Guo, Jiesi; Dicke, Theresa

2018-02-01

Our newly proposed integrated academic self-concept model integrates 3 major theories of academic self-concept formation and developmental perspectives into a unified conceptual and methodological framework. Relations among math self-concept (MSC), school grades, test scores, and school-level contextual effects over 6 years, from the end of primary school through the first 5 years of secondary school (a representative sample of 3,370 German students, 42 secondary schools, 50% male, M age at grade 5 = 11.75) support the (1) internal/external frame of reference model: Math school grades had positive effects on MSC, but the effects of German grades were negative; (2) reciprocal effects (longitudinal panel) model: MSC was predictive of and predicted by math test scores and school grades; (3) big-fish-little-pond effect: The effects on MSC were negative for school-average achievement based on 4 indicators (primary school grades in math and German, school-track prior to the start of secondary school, math test scores in the first year of secondary school). Results for all 3 theoretical models were consistent across the 5 secondary school years: This supports the prediction of developmental equilibrium. This integration highlights the robustness of support over the potentially volatile early to middle adolescent period; the interconnectedness and complementarity of 3 ASC models; their counterbalancing strengths and weaknesses; and new theoretical, developmental, and substantive implications at their intersections. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Harnessing Technology for Promoting Undergraduate Art Education: A Novel Model That Streamlines Learning between Classroom, Museum, and Home

ERIC Educational Resources Information Center

Kali, Yael; Sagy, Ornit; Kuflik, Tsvi; Mogilevsky, Orit; Maayan-Fanar, Emma

2015-01-01

We report on the development and evaluation of an innovative instructional model, which harnesses advanced technologies and local resources (an in-campus museum), to support undergraduate-level art history students in developing the skills required for analyzing artwork. Theory suggests that analyzing artwork requires theoretical knowledge and…

Developing Contextual Mathematical Thinking Learning Model to Enhance Higher-Order Thinking Ability for Middle School Students

ERIC Educational Resources Information Center

Samo, Damianus D.; Darhim; Kartasasmita, Bana

2017-01-01

The purpose of this research is to develop contextual mathematical thinking learning model which is valid, practical and effective based on the theoretical reviews and its support to enhance higher-order thinking ability. This study is a research and development (R & D) with three main phases: investigation, development, and implementation.…

Confirmatory Analysis of Simultaneous, Sequential, and Achievement Factors on the K-ABC at 11 Age Levels Ranging from 2 1/2 to 12 1/2 years.

ERIC Educational Resources Information Center

Willson, Victor L.; And Others

1985-01-01

Presents results of confirmatory factor analysis of the Kaufman Assessment Battery for children which is based on the underlying theoretical model of sequential, simultaneous, and achievement factors. Found support for the two-factor, simultaneous and sequential processing model. (MCF)

Using Rasch Modeling to Investigate a Learning Progression for Energy Ideas

ERIC Educational Resources Information Center

Herrmann-Abell, Cari F.; DeBoer, George E.

2016-01-01

Energy is a core concept in the teaching of science. Therefore, it is important to know how students' thinking about energy develops so that elementary, middle, and high school students can be appropriately supported in their understanding of energy. This study tests the validity of a proposed theoretical model of students' growth of understanding…

The Role of Social Contexts in Adolescence: Context Protection and Context Risk in the United States and China

ERIC Educational Resources Information Center

Costa, Frances M.; Jessor, Richard; Turbin, Mark S.; Dong, Qi; Zhang, Hongchuan; Wang, Changhai

2005-01-01

A theoretical framework about protective factors (models protection, controls protection, support protection) and risk factors (models risk, opportunity risk, vulnerability risk) was employed to articulate the content of 4 key contexts of adolescent life--family, peers, school, and neighborhood--in a cross-national study of problem behavior among…

Ottawa Model of Implementation Leadership and Implementation Leadership Scale: mapping concepts for developing and evaluating theory-based leadership interventions.

PubMed

Gifford, Wendy; Graham, Ian D; Ehrhart, Mark G; Davies, Barbara L; Aarons, Gregory A

2017-01-01

Leadership in health care is instrumental to creating a supportive organizational environment and positive staff attitudes for implementing evidence-based practices to improve patient care and outcomes. The purpose of this study is to demonstrate the alignment of the Ottawa Model of Implementation Leadership (O-MILe), a theoretical model for developing implementation leadership, with the Implementation Leadership Scale (ILS), an empirically validated tool for measuring implementation leadership. A secondary objective is to describe the methodological process for aligning concepts of a theoretical model with an independently established measurement tool for evaluating theory-based interventions. Modified template analysis was conducted to deductively map items of the ILS onto concepts of the O-MILe. An iterative process was used in which the model and scale developers (n=5) appraised the relevance, conceptual clarity, and fit of each ILS items with the O-MILe concepts through individual feedback and group discussions until consensus was reached. All 12 items of the ILS correspond to at least one O-MILe concept, demonstrating compatibility of the ILS as a measurement tool for the O-MILe theoretical constructs. The O-MILe provides a theoretical basis for developing implementation leadership, and the ILS is a compatible tool for measuring leadership based on the O-MILe. Used together, the O-MILe and ILS provide an evidence- and theory-based approach for developing and measuring leadership for implementing evidence-based practices in health care. Template analysis offers a convenient approach for determining the compatibility of independently developed evaluation tools to test theoretical models.

Ottawa Model of Implementation Leadership and Implementation Leadership Scale: mapping concepts for developing and evaluating theory-based leadership interventions

PubMed Central

Gifford, Wendy; Graham, Ian D; Ehrhart, Mark G; Davies, Barbara L; Aarons, Gregory A

2017-01-01

Purpose Leadership in health care is instrumental to creating a supportive organizational environment and positive staff attitudes for implementing evidence-based practices to improve patient care and outcomes. The purpose of this study is to demonstrate the alignment of the Ottawa Model of Implementation Leadership (O-MILe), a theoretical model for developing implementation leadership, with the Implementation Leadership Scale (ILS), an empirically validated tool for measuring implementation leadership. A secondary objective is to describe the methodological process for aligning concepts of a theoretical model with an independently established measurement tool for evaluating theory-based interventions. Methods Modified template analysis was conducted to deductively map items of the ILS onto concepts of the O-MILe. An iterative process was used in which the model and scale developers (n=5) appraised the relevance, conceptual clarity, and fit of each ILS items with the O-MILe concepts through individual feedback and group discussions until consensus was reached. Results All 12 items of the ILS correspond to at least one O-MILe concept, demonstrating compatibility of the ILS as a measurement tool for the O-MILe theoretical constructs. Conclusion The O-MILe provides a theoretical basis for developing implementation leadership, and the ILS is a compatible tool for measuring leadership based on the O-MILe. Used together, the O-MILe and ILS provide an evidence- and theory-based approach for developing and measuring leadership for implementing evidence-based practices in health care. Template analysis offers a convenient approach for determining the compatibility of independently developed evaluation tools to test theoretical models. PMID:29355212

Social class disparities in health and education: reducing inequality by applying a sociocultural self model of behavior.

PubMed

Stephens, Nicole M; Markus, Hazel Rose; Fryberg, Stephanie A

2012-10-01

The literature on social class disparities in health and education contains 2 underlying, yet often opposed, models of behavior: the individual model and the structural model. These models refer to largely unacknowledged assumptions about the sources of human behavior that are foundational to research and interventions. Our review and theoretical integration proposes that, in contrast to how the 2 models are typically represented, they are not opposed, but instead they are complementary sets of understandings that inform and extend each other. Further, we elaborate the theoretical rationale and predictions for a third model: the sociocultural self model of behavior. This model incorporates and extends key tenets of the individual and structural models. First, the sociocultural self model conceptualizes individual characteristics (e.g., skills) and structural conditions (e.g., access to resources) as interdependent forces that mutually constitute each other and that are best understood together. Second, the sociocultural self model recognizes that both individual characteristics and structural conditions indirectly influence behavior through the selves that emerge in the situation. These selves are malleable psychological states that are a product of the ongoing mutual constitution of individuals and structures and serve to guide people's behavior by systematically shaping how people construe situations. The theoretical foundation of the sociocultural self model lays the groundwork for a more complete understanding of behavior and provides new tools for developing interventions that will reduce social class disparities in health and education. The model predicts that intervention efforts will be more effective at producing sustained behavior change when (a) current selves are congruent, rather than incongruent, with the desired behavior and (b) individual characteristics and structural conditions provide ongoing support for the selves that are necessary to support the desired behavior. PsycINFO Database Record (c) 2012 APA, all rights reserved.

Dynamic load-sharing characteristic analysis of face gear power-split gear system based on tooth contact characteristics

NASA Astrophysics Data System (ADS)

Dong, Hao; Hu, Yahui

2018-04-01

The bend-torsion coupling dynamics load-sharing model of the helicopter face gear split torque transmission system is established by using concentrated quality standard, to analyzing the dynamic load-sharing characteristic. The mathematical models include nonlinear support stiffness, time-varying meshing stiffness, damping, gear backlash. The results showed that the errors collectively influenced the load sharing characteristics, only reduce a certain error, it is never fully reached the perfect loading sharing characteristics. The system load-sharing performance can be improved through floating shaft support. The above-method will provide a theoretical basis and data support for its dynamic performance optimization design.

[Analysis of the impact of job characteristics and organizational support for workplace violence].

PubMed

Li, M L; Chen, P; Zeng, F H; Cui, Q L; Zeng, J; Zhao, X S; Li, Z N

2017-12-20

Objective: To analyze the effect of job characteristics and organizational support for workplace violence, explore the influence path and the theoretical model, and provide a theoretical basis for reducing workplace violence. Methods: Stratified random sampling was used to select 813 medical staff, conductors and bus drivers in Chongqing with a self-made questionnaire to investigate job characteristics, organization attitude toward workplace violence, workplace violence, fear of violence, workplace violence, etc from February to October, 2014. Amos 21.0 was used to analyze the path and to establish a theoretical model of workplace violence. Results: The odds ratio of work characteristics and organizational attitude to workplace violence were 6.033 and 0.669, respectively, and the path coefficients were 0.41 and-0.14, respectively ( P <0.05). The Fitting indexes of the model: Chi-square (χ(2)) =67.835, The ratio of the chi-square to the degree of freedom (χ(2)/df) =5.112, Good-of-fit index (GFI) =0.970, Adjusted good-of-fit index (AGFI) =0.945, Normed fit index (NFI) =0.923, Root mean square error of approximation (RMSEA) =0.071, Fit criterion (Fmin) =0.092, so the model fit well with the data. Conclusion: The job characteristic is a risk factor for workplace violence while organizational attitude is a protective factor for workplace violence, so changing the job characteristics and improving the enthusiasm of the organization to deal with workplace violence are conducive to reduce workplace violence and increase loyalty to the unit.

A theoretical/experimental program to develop active optical pollution sensors

NASA Technical Reports Server (NTRS)

Mills, F. S.; Blais, R. N.; Kindle, E. C.

1977-01-01

Light detection and ranging (LIDAR) technology was applied to the assessment of air quality, and its usefulness was evaluated by actual field tests. Necessary hardware was successfully constructed and operated in the field. Measurements of necessary physical parameters, such as SO2 absorption coefficients were successfully completed and theoretical predictions of differential absorption performance were reported. Plume modeling improvements were proposed. A full scale field test of equipment, data analysis and auxiliary data support was conducted in Maryland during September 1976.

Theories, models and frameworks used in capacity building interventions relevant to public health: a systematic review.

PubMed

Bergeron, Kim; Abdi, Samiya; DeCorby, Kara; Mensah, Gloria; Rempel, Benjamin; Manson, Heather

2017-11-28

There is limited research on capacity building interventions that include theoretical foundations. The purpose of this systematic review is to identify underlying theories, models and frameworks used to support capacity building interventions relevant to public health practice. The aim is to inform and improve capacity building practices and services offered by public health organizations. Four search strategies were used: 1) electronic database searching; 2) reference lists of included papers; 3) key informant consultation; and 4) grey literature searching. Inclusion and exclusion criteria are outlined with included papers focusing on capacity building, learning plans, professional development plans in combination with tools, resources, processes, procedures, steps, model, framework, guideline, described in a public health or healthcare setting, or non-government, government, or community organizations as they relate to healthcare, and explicitly or implicitly mention a theory, model and/or framework that grounds the type of capacity building approach developed. Quality assessment were performed on all included articles. Data analysis included a process for synthesizing, analyzing and presenting descriptive summaries, categorizing theoretical foundations according to which theory, model and/or framework was used and whether or not the theory, model or framework was implied or explicitly identified. Nineteen articles were included in this review. A total of 28 theories, models and frameworks were identified. Of this number, two theories (Diffusion of Innovations and Transformational Learning), two models (Ecological and Interactive Systems Framework for Dissemination and Implementation) and one framework (Bloom's Taxonomy of Learning) were identified as the most frequently cited. This review identifies specific theories, models and frameworks to support capacity building interventions relevant to public health organizations. It provides public health practitioners with a menu of potentially usable theories, models and frameworks to support capacity building efforts. The findings also support the need for the use of theories, models or frameworks to be intentional, explicitly identified, referenced and for it to be clearly outlined how they were applied to the capacity building intervention.

Understanding sport continuation: an integration of the theories of planned behaviour and basic psychological needs.

PubMed

Gucciardi, Daniel F; Jackson, Ben

2015-01-01

Fostering individuals' long-term participation in activities that promote positive development such as organised sport is an important agenda for research and practice. We integrated the theories of planned behaviour (TPB) and basic psychological needs (BPN) to identify factors associated with young adults' continuation in organised sport over a 12-month period. Prospective study, including an online psycho-social assessment at Time 1 and an assessment of continuation in sport approximately 12 months later. Participants (N=292) aged between 17 and 21 years (M=18.03; SD=1.29) completed an online survey assessing the theories of planned behaviour and basic psychological needs constructs. Bayesian structural equation modelling (BSEM) was employed to test the hypothesised theoretical sequence, using informative priors for structural relations based on empirical and theoretical expectations. The analyses revealed support for the robustness of the hypothesised theoretical model in terms of the pattern of relations as well as the direction and strength of associations among the constructs derived from quantitative summaries of existing research and theoretical expectations. The satisfaction of basic psychological needs was associated with more positive attitudes, higher levels of perceived behavioural control, and more favourable subjective norms; positive attitudes and perceived behavioural control were associated with higher behavioural intentions; and both intentions and perceived behavioural control predicted sport continuation. This study demonstrated the utility of Bayesian structural equation modelling for testing the robustness of an integrated theoretical model, which is informed by empirical evidence from meta-analyses and theoretical expectations, for understanding sport continuation. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

On Utilizing Optimal and Information Theoretic Syntactic Modeling for Peptide Classification

NASA Astrophysics Data System (ADS)

Aygün, Eser; Oommen, B. John; Cataltepe, Zehra

Syntactic methods in pattern recognition have been used extensively in bioinformatics, and in particular, in the analysis of gene and protein expressions, and in the recognition and classification of bio-sequences. These methods are almost universally distance-based. This paper concerns the use of an Optimal and Information Theoretic (OIT) probabilistic model [11] to achieve peptide classification using the information residing in their syntactic representations. The latter has traditionally been achieved using the edit distances required in the respective peptide comparisons. We advocate that one can model the differences between compared strings as a mutation model consisting of random Substitutions, Insertions and Deletions (SID) obeying the OIT model. Thus, in this paper, we show that the probability measure obtained from the OIT model can be perceived as a sequence similarity metric, using which a Support Vector Machine (SVM)-based peptide classifier, referred to as OIT_SVM, can be devised.

Engaging and supporting fathers to promote breast feeding: a concept analysis.

PubMed

Sherriff, Nigel; Hall, Valerie; Panton, Christina

2014-06-01

Empirical evidence demonstrates that fathers have a strong influence on a mother's decision to initiate and continue breast feeding. However, no clear delineation of what behaviours and attributes constitute father support or differentiate it from other kinds of support is provided in the current literature. The purpose of this study was to analyse the concept of 'father support' in relation to maternity services and broader health settings, thereby clarifying meaning to enable comprehension and application in practice, education, and research. A concept analysis combining the evolutionary model of concept development with the inter-related theoretical, fieldwork and analytical phases of the hybrid model of concept development. Children's Centres in East and West Sussex in Southern England. Repeated qualitative research over two phases with 16 parents of breast fed infants through seven focus groups and five telephone interviews. CINAHL, PsycINFO, AMED, MEDLINE, OVID and EMBASE databases were searched for articles published in English between 1999 and 2013 using the keywords breast feeding, father, and support. Seven same-sex focus groups and five individual interviews were also conducted over two research phases with the parents of breast fed infants to expand and exemplify, and then validate the analysis of the literature search. Five main attributes of father support in relation to breast feeding were identified: (1) knowledge about breast feeding; (2) positive attitude to breast feeding; (3) involvement in the decision-making process; (4) practical support; and (5) emotional support. Multiple antecedents and consequences to these attributes were also identified. This study has contributed to clarifying the meaning of father support in relation to breast feeding and provides an important starting point for the development of a theoretical and practical model of optimal breast feeding that takes into account father support. Identification of attributes, antecedents, and consequences of father support may assist practitioners to reflect on current working practices and service delivery models, and offer important educational opportunities for the training of student midwives and other health professionals. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

A new theoretical approach to analyze complex processes in cytoskeleton proteins.

PubMed

Li, Xin; Kolomeisky, Anatoly B

2014-03-20

Cytoskeleton proteins are filament structures that support a large number of important biological processes. These dynamic biopolymers exist in nonequilibrium conditions stimulated by hydrolysis chemical reactions in their monomers. Current theoretical methods provide a comprehensive picture of biochemical and biophysical processes in cytoskeleton proteins. However, the description is only qualitative under biologically relevant conditions because utilized theoretical mean-field models neglect correlations. We develop a new theoretical method to describe dynamic processes in cytoskeleton proteins that takes into account spatial correlations in the chemical composition of these biopolymers. Our approach is based on analysis of probabilities of different clusters of subunits. It allows us to obtain exact analytical expressions for a variety of dynamic properties of cytoskeleton filaments. By comparing theoretical predictions with Monte Carlo computer simulations, it is shown that our method provides a fully quantitative description of complex dynamic phenomena in cytoskeleton proteins under all conditions.

A theoretical approach to medication adherence for children and youth with psychiatric disorders.

PubMed

Charach, Alice; Volpe, Tiziana; Boydell, Katherine M; Gearing, Robin E

2008-01-01

This article provides a theoretical review of treatment adherence for children and youth with psychiatric disorders where pharmacological agents are first-line interventions. Four empirically based models of health behavior are reviewed and applied to the sparse literature about medication adherence for children with attention-deficit/hyperactivity disorder and young people with first-episode psychosis. Three qualitative studies of medication use are summarized, and details from the first-person narratives are used to illustrate the theoretical models. These studies indicate, when taken together, that the clinical approach to addressing poor medication adherence in children and youth with psychiatric disorders should be guided by more than one theoretical model. Mental health experts should clarify beliefs, address misconceptions, and support exploration of alternative treatment options unless contraindicated. Recognizing the larger context of the family, allowing time for parents and children to change their attitudes, and offering opportunities for easy access to medication in the future are important ways of respecting patient preferences, while steering them toward best-evidence interventions. Future research using qualitative methods of inquiry to investigate parent, child, and youth experiences of mental health interventions should identify effective ways to improve treatment adherence.

Theoretical studies on sRNA-mediated regulation in bacteria

NASA Astrophysics Data System (ADS)

Chang, Xiao-Xue; Xu, Liu-Fang; Shi, Hua-Lin

2015-12-01

Small RNA(sRNA)-mediated post-transcriptional regulation differs from protein-mediated regulation. Through base-pairing, sRNA can regulate the target mRNA in a catalytic or stoichiometric manner. Some theoretical models were built for comparison of the protein-mediated and sRNA-mediated modes in the steady-state behaviors and noise properties. Many experiments demonstrated that a single sRNA can regulate several mRNAs, which causes crosstalk between the targets. Here, we focus on some models in which two target mRNAs are silenced by the same sRNA to discuss their crosstalk features. Additionally, the sequence-function relationship of sRNA and its role in the kinetic process of base-pairing have been highlighted in model building. Project supported by the National Basic Research Program of China (Grant No. 2013CB834100), the National Natural Science Foundation of China (Grant Nos. 11121403 and 11274320), the Open Project Program of State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, China (Grant No. Y4KF171CJ1), the National Natural Science Foundation for Young Scholar of China (Grant No. 11304115), and the China Postdoctoral Science Foundation (Grant No. 2013M541282).

In search of how people change. Applications to addictive behaviors.

PubMed

Prochaska, J O; DiClemente, C C; Norcross, J C

1992-09-01

How people intentionally change addictive behaviors with and without treatment is not well understood by behavioral scientists. This article summarizes research on self-initiated and professionally facilitated change of addictive behaviors using the key trans-theoretical constructs of stages and processes of change. Modification of addictive behaviors involves progression through five stages--pre-contemplation, contemplation, preparation, action, and maintenance--and individuals typically recycle through these stages several times before termination of the addiction. Multiple studies provide strong support for these stages as well as for a finite and common set of change processes used to progress through the stages. Research to date supports a trans-theoretical model of change that systematically integrates the stages with processes of change from diverse theories of psychotherapy.

Perceived autonomy support, friendship maintenance, and happiness.

PubMed

Demir, Melikşah; Ozdemir, Metin; Marum, Kendra Patrice

2011-01-01

Decades of empirical research have shown that perceived autonomy support in close relationships is an essential correlate of happiness. However, what might account for the relationship between the 2? For this article, 4 studies (total N=1325) investigated friendship maintenance as a mediator of the association between friendship autonomy support and happiness. The first 3 studies supported the model for the best friendship of the individual when happiness was assessed with 3 different measures. The 4th study extended the findings by showing that the model was generalizable to the other close friendship of the individual. Overall, the results supported the idea that engaging in routine and strategic behaviors to maintain friendships explains how perceived autonomy support in friendships is associated with happiness. The theoretical and applied implications of the findings were discussed and suggestions for future research were made.

Optimum design for effective water transport through a double-layered porous hydrogel inspired by plant leaves

NASA Astrophysics Data System (ADS)

Kim, Hyejeong; Kim, Hyeonjeong; Huh, Hyungkyu; Hwang, Hyung Ju; Lee, Sang Joon

2014-11-01

Plant leaves are generally known to have optimized morphological structure in response to environmental changes for efficient water usage. However, the advantageous features of plant leaves are not fully utilized in engineering fields yet, since the optimum design in internal structure of plant leaves is unclear. In this study, the tissue organization of the hydraulic pathways inside plant leaves was investigated. Water transport through double-layered porous hydrogel models analogous to mesophyll cells was experimentally observed. In addition, computational experiment and theoretical analysis were applied to the model systems to find the optimal design for efficient water transport. As a result, the models with lower porosity or with pores distributed widely in the structure exhibit efficient mass transport. Our theoretical prediction supports that structural features of plant leaves guarantee sufficient water supply as survival strategy. This study may provide a new framework for investigating the biophysical principles governing the morphological optimization of plant leaves and for designing microfluidic devices to enhance mass transport ability. This study was supported by the National Research Foundation of Korea and funded by the Korean government.

Stochastic modelling, Bayesian inference, and new in vivo measurements elucidate the debated mtDNA bottleneck mechanism

PubMed Central

Johnston, Iain G; Burgstaller, Joerg P; Havlicek, Vitezslav; Kolbe, Thomas; Rülicke, Thomas; Brem, Gottfried; Poulton, Jo; Jones, Nick S

2015-01-01

Dangerous damage to mitochondrial DNA (mtDNA) can be ameliorated during mammalian development through a highly debated mechanism called the mtDNA bottleneck. Uncertainty surrounding this process limits our ability to address inherited mtDNA diseases. We produce a new, physically motivated, generalisable theoretical model for mtDNA populations during development, allowing the first statistical comparison of proposed bottleneck mechanisms. Using approximate Bayesian computation and mouse data, we find most statistical support for a combination of binomial partitioning of mtDNAs at cell divisions and random mtDNA turnover, meaning that the debated exact magnitude of mtDNA copy number depletion is flexible. New experimental measurements from a wild-derived mtDNA pairing in mice confirm the theoretical predictions of this model. We analytically solve a mathematical description of this mechanism, computing probabilities of mtDNA disease onset, efficacy of clinical sampling strategies, and effects of potential dynamic interventions, thus developing a quantitative and experimentally-supported stochastic theory of the bottleneck. DOI: http://dx.doi.org/10.7554/eLife.07464.001 PMID:26035426

LONG-TERM IMPACTS OF ORTHOPHOSPHATE TREATMENT ON COPPER

EPA Science Inventory

Laboratory, pilot, and field data collected support the theoretical "cupric hydroxide" copper solubility model. For the short time frames inherent in laboratory and pilot studies of copper solubility and in initial field monitoring for the LCR from Tier 1 soldered copper sites, c...

The Development of an Empirical Model of Mental Health Stigma in Adolescents.

PubMed

Silke, Charlotte; Swords, Lorraine; Heary, Caroline

2016-08-30

Research on mental health stigma in adolescents is hampered by a lack of empirical investigation into the theoretical conceptualisation of stigma, as well as by the lack of validated stigma measures. This research aims to develop a model of public stigma toward depression in adolescents and to use this model to empirically examine whether stigma is composed of three separate dimensions (Stereotypes, Prejudice and Discrimination), as is theoretically proposed. Adolescents completed self-report measures assessing their stigmatising responses toward a fictional peer with depression. An exploratory factor analysis (EFA; N=332) was carried out on 58-items, which proposed to measure aspects of stigma. A confirmatory factor analysis (CFA; N=236) was then carried out to evaluate the validity of the observed stigma model. Finally, higher-order CFAs were conducted in order to assess whether the observed model supported the tripartite conceptualisation of stigma. The EFA returned a seven-factor model of stigma. These factors were designated as Dangerousness, Warmth & Competency, Responsibility, Negative Attributes, Prejudice, Classroom Discrimination and Friendship Discrimination. The CFA supported the goodness-of-fit of this seven-factor model. The higher-order CFAs indicated that these seven factors represented the latent constructs of, Stereotypes, Prejudice and Discrimination, which in turn represented Stigma. Overall, results support the tripartite conceptualisation of stigma and suggest that measurements of mental health stigma in adolescents should include assessments of all three dimensions. These results also highlight the importance of establishing valid and reliable measures for assessing stigma in adolescents. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

An examination of stress and burnout in certified athletic trainers at division I-a universities.

PubMed

Hendrix, A E; Acevedo, E O; Hebert, E

2000-04-01

A growing body of knowledge indicates that too much stress can negatively influence psychological and physical health. A model proposed by Smith to explore personal and situational variables, stress appraisal, and burnout has led to significant understanding of burnout of individuals working in service professions. We examined the relationship of hardiness, social support, and work-related issues relevant to athletic trainers to perceived stress and the relationship of perceived stress to burnout. Correlational analyses were performed to examine the relationships predicted by Smith's model. In addition, we conducted stepwise multiple regression analyses to assess the relative contributions of the personal and situational variables to perceived stress and to examine the relative impact of perceived stress on 3 burnout factors (emotional exhaustion, personal accomplishment, and depersonalization). One hundred eighteen certified athletic trainers working in National Collegiate Athletic Association Division I-A intercollegiate settings that maintain a football program. We assessed personal and situational variables using the Hardiness Test, the Social Support Questionnaire, and the Athletic Training Issues Survey, adapted for this study. The Perceived Stress Scale was used to assess stress appraisal, and the Maslach Burnout Inventory was used to assess 3 dimensions of burnout. Our results were in support of Smith's theoretical model of stress and burnout. Athletic trainers who scored lower on hardiness and social support and higher on athletic training issues tended to have higher levels of perceived stress. Furthermore, higher perceived stress scores were related to higher emotional exhaustion and depersonalization and lower levels of personal accomplishment. Our findings examining burnout in Division I athletic trainers were similar to those of other studies investigating coaches and coach-teachers and in support of Smith's theoretical model of stress and burnout.

Seeking for the rational basis of the median model: the optimal combination of multi-model ensemble results

NASA Astrophysics Data System (ADS)

Riccio, A.; Giunta, G.; Galmarini, S.

2007-04-01

In this paper we present an approach for the statistical analysis of multi-model ensemble results. The models considered here are operational long-range transport and dispersion models, also used for the real-time simulation of pollutant dispersion or the accidental release of radioactive nuclides. We first introduce the theoretical basis (with its roots sinking into the Bayes theorem) and then apply this approach to the analysis of model results obtained during the ETEX-1 exercise. We recover some interesting results, supporting the heuristic approach called "median model", originally introduced in Galmarini et al. (2004a, b). This approach also provides a way to systematically reduce (and quantify) model uncertainties, thus supporting the decision-making process and/or regulatory-purpose activities in a very effective manner.

Seeking for the rational basis of the Median Model: the optimal combination of multi-model ensemble results

NASA Astrophysics Data System (ADS)

Riccio, A.; Giunta, G.; Galmarini, S.

2007-12-01

In this paper we present an approach for the statistical analysis of multi-model ensemble results. The models considered here are operational long-range transport and dispersion models, also used for the real-time simulation of pollutant dispersion or the accidental release of radioactive nuclides. We first introduce the theoretical basis (with its roots sinking into the Bayes theorem) and then apply this approach to the analysis of model results obtained during the ETEX-1 exercise. We recover some interesting results, supporting the heuristic approach called "median model", originally introduced in Galmarini et al. (2004a, b). This approach also provides a way to systematically reduce (and quantify) model uncertainties, thus supporting the decision-making process and/or regulatory-purpose activities in a very effective manner.

On the road to metallic nanoparticles by rational design: bridging the gap between atomic-level theoretical modeling and reality by total scattering experiments.

PubMed

Prasai, Binay; Wilson, A R; Wiley, B J; Ren, Y; Petkov, Valeri

2015-11-14

The extent to which current theoretical modeling alone can reveal real-world metallic nanoparticles (NPs) at the atomic level was scrutinized and demonstrated to be insufficient and how it can be improved by using a pragmatic approach involving straightforward experiments is shown. In particular, 4 to 6 nm in size silica supported Au(100-x)Pd(x) (x = 30, 46 and 58) explored for catalytic applications is characterized structurally by total scattering experiments including high-energy synchrotron X-ray diffraction (XRD) coupled to atomic pair distribution function (PDF) analysis. Atomic-level models for the NPs are built by molecular dynamics simulations based on the archetypal for current theoretical modeling Sutton-Chen (SC) method. Models are matched against independent experimental data and are demonstrated to be inaccurate unless their theoretical foundation, i.e. the SC method, is supplemented with basic yet crucial information on the length and strength of metal-to-metal bonds and, when necessary, structural disorder in the actual NPs studied. An atomic PDF-based approach for accessing such information and implementing it in theoretical modeling is put forward. For completeness, the approach is concisely demonstrated on 15 nm in size water-dispersed Au particles explored for bio-medical applications and 16 nm in size hexane-dispersed Fe48Pd52 particles explored for magnetic applications as well. It is argued that when "tuned up" against experiments relevant to metals and alloys confined to nanoscale dimensions, such as total scattering coupled to atomic PDF analysis, rather than by mere intuition and/or against data for the respective solids, atomic-level theoretical modeling can provide a sound understanding of the synthesis-structure-property relationships in real-world metallic NPs. Ultimately this can help advance nanoscience and technology a step closer to producing metallic NPs by rational design.

Thinking meta-theoretically about the role of internalization in the development of body dissatisfaction and body change behaviors.

PubMed

Karazsia, Bryan T; van Dulmen, Manfred H M; Wong, Kendal; Crowther, Janis H

2013-09-01

Internalization of societal standards of physical attractiveness (i.e., internalization of the thin ideal for women and internalization of the mesomorphic ideal for men) is a widely studied and robust risk factor for body dissatisfaction and maladaptive body change behaviors. Substantial empirical research supports internalization as both a mediator and a moderator of the relation between societal influences and body dissatisfaction. In this paper, a primer on mediation and moderation is followed by a review of literature and discussion of the extent to which internalization can theoretically fulfill the roles of both mediation and moderation. The literature review revealed a stark contrast in research design (experimental versus non-experimental design) when alternate conceptualizations of internalization are adopted. A meta-theoretical, moderated mediation model is presented. This model integrates previous research and can inform future empirical and clinical endeavors. Copyright © 2013 Elsevier Ltd. All rights reserved.

Utilized social support and self-esteem mediate the relationship between perceived social support and suicide ideation. A test of a multiple mediator model.

PubMed

Kleiman, Evan M; Riskind, John H

2013-01-01

While perceived social support has received considerable research as a protective factor for suicide ideation, little attention has been given to the mechanisms that mediate its effects. We integrated two theoretical models, Joiner's (2005) interpersonal theory of suicide and Leary's (Leary, Tambor, Terdal, & Downs, 1995) sociometer theory of self-esteem to investigate two hypothesized mechanisms, utilization of social support and self-esteem. Specifically, we hypothesized that individuals must utilize the social support they perceive that would result in increased self-esteem, which in turn buffers them from suicide ideation. Participants were 172 college students who completed measures of social support, self-esteem, and suicide ideation. Tests of simple mediation indicate that utilization of social support and self-esteem may each individually help to mediate the perceived social support/suicide ideation relationship. Additionally, a test of multiple mediators using bootstrapping supported the hypothesized multiple-mediator model. The use of a cross-sectional design limited our ability to find true cause-and-effect relationships. Results suggested that utilized social support and self-esteem both operate as individual moderators in the social support/self-esteem relationship. Results further suggested, in a comprehensive model, that perceived social support buffers suicide ideation through utilization of social support and increases in self-esteem.

Simulation of physiological systems in order to evaluate and predict the human condition in a space flight

NASA Technical Reports Server (NTRS)

Verigo, V. V.

1979-01-01

Simulation models were used to study theoretical problems of space biology and medicine. The reaction and adaptation of the main physiological systems to the complex effects of space flight were investigated. Mathematical models were discussed in terms of their significance in the selection of the structure and design of biological life support systems.

Membership in a Devalued Social Group and Emotional Well-Being: Developing a Model of Personal Self-Esteem, Collective Self-Esteem, and Group Socialization.

ERIC Educational Resources Information Center

Katz, Jennifer; Joiner, Thomas E., Jr.; Kwon, Paul

2002-01-01

Tested a theoretical model that linked membership in a devalued social group to emotional health. Surveyed white, middle-to-upper-class undergraduate students regarding personal and collective self-esteem (by gender), attitudes and behaviors associated with female socialization, and emotional distress. Results supported the direct effect of each…

Educational Process Reflection (EPR): An Evaluation of a Model for Professional Development Concerning Social Interaction and Educational Climate in the Swedish Preschool

ERIC Educational Resources Information Center

Bygdeson-Larsson, Kerstin

2006-01-01

Educational process reflection (EPR) is a professional development model aimed at supporting preschool teachers reflecting on and changing their practice. A particular focus is on interaction between practitioners and children, and between the children themselves. In this article, I first describe the theoretical frameworks that helped shape EPR,…

Searching Nearest Potential of Children with Intellectual Disability--Dynamic Assessment

ERIC Educational Resources Information Center

Kulesza, Ewa Maria

2015-01-01

The article discussed the issue of the diagnosis with the use of task-support-task procedure. A theoretical model of diagnosis based on the concepts by L. S. Vygotski, R. Case, and A. Bandura was described and developed. The model was tested on a group of non-disabled preschool children, and children with mild and moderate intellectual disability…

The Woodcock-Johnson Tests of Cognitive Abilities III's Cognitive Performance Model: Empirical Support for Intermediate Factors within CHC Theory

ERIC Educational Resources Information Center

Taub, Gordon E.; McGrew, Kevin S.

2014-01-01

The Woodcock-Johnson Tests of Cognitive Ability Third Edition is developed using the Cattell-Horn-Carroll (CHC) measurement-theory test design as the instrument's theoretical blueprint. The instrument provides users with cognitive scores based on the Cognitive Performance Model (CPM); however, the CPM is not a part of CHC theory. Within the…

Cognitive engineering models in space systems

NASA Technical Reports Server (NTRS)

Mitchell, Christine M.

1992-01-01

NASA space systems, including mission operations on the ground and in space, are complex, dynamic, predominantly automated systems in which the human operator is a supervisory controller. The human operator monitors and fine-tunes computer-based control systems and is responsible for ensuring safe and efficient system operation. In such systems, the potential consequences of human mistakes and errors may be very large, and low probability of such events is likely. Thus, models of cognitive functions in complex systems are needed to describe human performance and form the theoretical basis of operator workstation design, including displays, controls, and decision support aids. The operator function model represents normative operator behavior-expected operator activities given current system state. The extension of the theoretical structure of the operator function model and its application to NASA Johnson mission operations and space station applications is discussed.

Childhood maltreatment and college students' current suicidal ideation: a test of the hopelessness theory.

PubMed

Gibb, B E; Alloy, L B; Abramson, L Y; Rose, D T; Whitehouse, W G; Hogan, M E

2001-01-01

Few studies have examined the relation between childhood maltreatment and adult suicidality within the context of a coherent theoretical model. The current study evaluates the ability of the hopelessness theory of depression's (Abramson, Metalsky, & Alloy, 1989) etiological chain to account for this relation in a sample of 297 undergraduates. Supporting the model, emotional, but not physical or sexual, maltreatment was uniquely related to average levels of suicidal ideation across a 2.5-year follow-up. Further, students' cognitive styles and average levels of hopelessness partially mediated this relation. Although these results cannot speak to causality, they support the developmental model evaluated.

Managing in the Contemporary World: Rape Victims' and Supporters' Experiences of Barriers within the Police and the Health Care System in Tanzania

ERIC Educational Resources Information Center

Muganyizi, Projestine S.; Nystrom, Lennarth; Axemo, Pia; Emmelin, Maria

2011-01-01

Grounded theory guided the analysis of 30 in-depth interviews with raped women and community members who had supported raped women in their contact with the police and health care services in Tanzania. The aim of this study was to understand and conceptualize the experiences of the informants by creating a theoretical model focusing on barriers,…

Negotiation Support System’s Impact on the Socio-Emotional Environment: A Research Design Framework

DTIC Science & Technology

1992-03-01

conflict environment and develop some proposed effects that Negotiation Support Systems (NSS) have on the socio- emotional climate. This introduction of...assessment of current NSS structure, processes and capabilities. Section IV provides a theoretical discussion of conflict and the socio- emotional environment ...model. First, strict economic rationalization does not take into account social/normative issues present --n the negotiation environment . Thus, in an

Modeling and Theoretical Analysis of On-Chip Phase-Sensitive Amplifiers

DTIC Science & Technology

2016-04-19

PERCENT_SUPPORTEDNAME FTE Equivalent: Total Number: Sub Contractors (DD882) Names of Faculty Supported Names of Under Graduate students supported Names of... ht )]Rsp(N, t′ − t). (26) Using the stationarity of Rsp , we may express the above as 〈r∗k (N ; z)rh (N ; z′)〉 = δk,hδ(z − z′)ω0 ×nsp(N,ω0 + kΩ)Γg(N

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

PubMed

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 Thematic Analysis of Theoretical Models for Translational Science in Nursing: Mapping the Field

PubMed Central

Mitchell, Sandra A.; Fisher, Cheryl A.; Hastings, Clare E.; Silverman, Leanne B.; Wallen, Gwenyth R.

2010-01-01

Background The quantity and diversity of conceptual models in translational science may complicate rather than advance the use of theory. Purpose This paper offers a comparative thematic analysis of the models available to inform knowledge development, transfer, and utilization. Method Literature searches identified 47 models for knowledge translation. Four thematic areas emerged: (1) evidence-based practice and knowledge transformation processes; (2) strategic change to promote adoption of new knowledge; (3) knowledge exchange and synthesis for application and inquiry; (4) designing and interpreting dissemination research. Discussion This analysis distinguishes the contributions made by leaders and researchers at each phase in the process of discovery, development, and service delivery. It also informs the selection of models to guide activities in knowledge translation. Conclusions A flexible theoretical stance is essential to simultaneously develop new knowledge and accelerate the translation of that knowledge into practice behaviors and programs of care that support optimal patient outcomes. PMID:21074646

Dementia service centres in Austria: A comprehensive support and early detection model for persons with dementia and their caregivers – theoretical foundations and model description

PubMed Central

Span, Edith; Reisberg, Barry

2015-01-01

Despite the highly developed social services in Austria, the County of Upper Austria, one of the nine counties of Austria had only very limited specialized services for persons with dementia and their caregivers in 2001. Support groups existed in which the desire for more specialized services was voiced. In response to this situation, funding was received to develop a new structure for early disease detection and long term support for both the person with dementia and their caregivers. This article describes the development of the model of the Dementia Service Centres (DSCs) and the successes and difficulties encountered in the process of implementing the model in six different rural regions of Upper Austria. The DSC was described in the First Austrian Dementia Report as one of the potential service models for the future. PMID:24339114

Dementia service centres in Austria: A comprehensive support and early detection model for persons with dementia and their caregivers - theoretical foundations and model description.

PubMed

Auer, Stefanie R; Span, Edith; Reisberg, Barry

2015-07-01

Despite the highly developed social services in Austria, the County of Upper Austria, one of the nine counties of Austria had only very limited specialized services for persons with dementia and their caregivers in 2001. Support groups existed in which the desire for more specialized services was voiced. In response to this situation, funding was received to develop a new structure for early disease detection and long term support for both the person with dementia and their caregivers. This article describes the development of the model of the Dementia Service Centres (DSCs) and the successes and difficulties encountered in the process of implementing the model in six different rural regions of Upper Austria. The DSC was described in the First Austrian Dementia Report as one of the potential service models for the future. © The Author(s) 2013.

Perceived Organizational Support for Enhancing Welfare at Work: A Regression Tree Model

PubMed Central

Giorgi, Gabriele; Dubin, David; Perez, Javier Fiz

2016-01-01

When trying to examine outcomes such as welfare and well-being, research tends to focus on main effects and take into account limited numbers of variables at a time. There are a number of techniques that may help address this problem. For example, many statistical packages available in R provide easy-to-use methods of modeling complicated analysis such as classification and tree regression (i.e., recursive partitioning). The present research illustrates the value of recursive partitioning in the prediction of perceived organizational support in a sample of more than 6000 Italian bankers. Utilizing the tree function party package in R, we estimated a regression tree model predicting perceived organizational support from a multitude of job characteristics including job demand, lack of job control, lack of supervisor support, training, etc. The resulting model appears particularly helpful in pointing out several interactions in the prediction of perceived organizational support. In particular, training is the dominant factor. Another dimension that seems to influence organizational support is reporting (perceived communication about safety and stress concerns). Results are discussed from a theoretical and methodological point of view. PMID:28082924

Refinements in the hierarchical structure of externalizing psychiatric disorders: Patterns of lifetime liability from mid-adolescence through early adulthood.

PubMed

Farmer, Richard F; Seeley, John R; Kosty, Derek B; Lewinsohn, Peter M

2009-11-01

Research on hierarchical modeling of psychopathology has frequently identified 2 higher order latent factors, internalizing and externalizing. When based on the comorbidity of psychiatric diagnoses, the externalizing domain has usually been modeled as a single latent factor. Multivariate studies of externalizing symptom features, however, suggest multidimensionality. To address this apparent contradiction, confirmatory factor analytic methods and information-theoretic criteria were used to evaluate 4 theoretically plausible measurement models based on lifetime comorbidity patterns of 7 putative externalizing disorders. Diagnostic information was collected at 4 assessment waves from an age-based cohort of 816 persons between the ages of 14 and 33. A 2-factor model that distinguished oppositional behavior disorders (attention-deficit/hyperactivity disorder, oppositional defiant disorder) from social norm violation disorders (conduct disorder, adult antisocial behavior, alcohol use disorder, cannabis use disorder, hard drug use disorder) demonstrated consistently good fit and superior approximating abilities. Analyses of psychosocial outcomes measured at the last assessment wave supported the validity of this 2-factor model. Implications of this research for the theoretical understanding of domain-related disorders and the organization of classification systems are discussed. PsycINFO Database Record 2009 APA, all rights reserved.

LONG-TERM IMPACTS OF ORTHOPHOSPHATE TREATMENT ON COPPER LEVELS - PRESENTATION

EPA Science Inventory

Laboratory, pilot, and field data collected support the theoretical "cupric hydroxide" copper solubility model. For the short time frames inherent in laboratory and pilot studies of copper solubility and in initial field monitoring for the LCR from Tier 1 soldered copper sites, c...

Long-Term Effects of Orthophosphate Treatment on Copper Concentration

EPA Science Inventory

Laboratory, pilot, and field data collected support the theoretical “cupric hydroxide” copper solubility model. For the short time frames inherent in laboratory and pilot studies of copper solubility, and in initial field monitoring for the LCR from Tier 1 soldered copper sites,...

LONG-TERM IMPACTS OF ORTHOPHOSPHATE TREATMENT ON COPPER LEVELS

EPA Science Inventory

Laboratory, pilot, and field data collected support the theoretical “cupric hydroxide” copper solubility model. For the short time frames inherent in laboratory and pilot studies of copper solubility and in initial field monitoring for the LCR from Tier 1 soldered copper sites,...

Readability and Recall of Short Prose Passages: A Theoretical Analysis.

ERIC Educational Resources Information Center

Miller, James R.; Kintsch, Walter

1980-01-01

To support the view of readability as an interaction between a text and the reader's prose-processing capabilities, this article applies an extended and formalized version of the Kintch and van Dijk prose-processing model to 20 texts of varying readability. (Author/GSK)

Person-centered work environments, psychological safety, and positive affect in healthcare: a theoretical framework.

PubMed

Rathert, Cheryl; May, Douglas R

2008-01-01

We propose that in order to systematically improve healthcare quality, healthcare organizations (HCOs) need work environments that are person-centered: environments that support the careprovider as well as the patient. We further argue that HCOs have a moral imperative to provide a workplace where professional care standards can be achieved. We draw upon a large body of research from several disciplines to propose and articulate a theoretical framework that explains how the work environment should be related to the well-being of patients and careproviders, that is, the potential mediating mechanisms. Person-centered work environments include: 1. Climates for patient-centered care. 2. Climates for quality improvement. 3. Benevolent ethical climates. Such a work environment should support the provision of patient-centered care, and should lead to positive psychological states for careproviders, including psychological safety and positive affect. The model contributes to theory by specifying relationships between important organizational variables. The model can potentially contribute to practice by linking specific work environment attributes to outcomes for careproviders and patients.

Cardinal and deep uterosacral ligament lines of action: MRI based 3D technique development and preliminary findings in normal women

PubMed Central

Ramanah, Rajeev; Hsu, Yvonne; Ashton-Miller, James A.; DeLancey, John O. L.

2014-01-01

Introduction and hypothesis The cardinal ligament (CL) and deep uterosacral ligament (US) play a critical role in utero-vaginal support. This study aims to quantify their geometrical relationships in living women using a MRI-based 3D technique. Methods The angles between ligaments, the ligaments length and curvature were assessed on 3D models constructed from twenty MRIs of volunteers with normal support. How angle variation theoretically affects ligament tension was investigated using a simplified biomechanical model. Results The CLs are 18.1 °±6.8 °(SD) from the cephalic-caudal body axis , and the USs are dorsally directed and 92.5 °±13.5 from the body axis. The CLs are longer and more curved than US. The theoretical calculated tension on CL is 52 % larger than that on US. Conclusions The CL is relatively parallel to the body axis while the US is dorsally directed. The tensions on these ligaments are affected by their orientations. PMID:22618207

Thermal conductivity of molten salt mixtures: Theoretical model supported by equilibrium molecular dynamics simulations.

PubMed

Gheribi, Aïmen E; Chartrand, Patrice

2016-02-28

A theoretical model for the description of thermal conductivity of molten salt mixtures as a function of composition and temperature is presented. The model is derived by considering the classical kinetic theory and requires, for its parametrization, only information on thermal conductivity of pure compounds. In this sense, the model is predictive. For most molten salt mixtures, no experimental data on thermal conductivity are available in the literature. This is a hindrance for many industrial applications (in particular for thermal energy storage technologies) as well as an obvious barrier for the validation of the theoretical model. To alleviate this lack of data, a series of equilibrium molecular dynamics (EMD) simulations has been performed on several molten chloride systems in order to determine their thermal conductivity in the entire range of composition at two different temperatures: 1200 K and 1300 K. The EMD simulations are first principles type, as the potentials used to describe the interactions have been parametrized on the basis of first principle electronic structure calculations. In addition to the molten chlorides system, the model predictions are also compared to a recent similar EMD study on molten fluorides and with the few reliable experimental data available in the literature. The accuracy of the proposed model is within the reported numerical and/or experimental errors.

When the customer is unethical: the explanatory role of employee emotional exhaustion onto work-family conflict, relationship conflict with coworkers, and job neglect.

PubMed

Greenbaum, Rebecca L; Quade, Matthew J; Mawritz, Mary B; Kim, Joongseo; Crosby, Durand

2014-11-01

We integrate deontological ethics (Folger, 1998, 2001; Kant, 1785/1948, 1797/1991) with conservation of resources theory (Hobfoll, 1989) to propose that an employee's repeated exposure to violations of moral principle can diminish the availability of resources to appropriately attend to other personal and work domains. In particular, we identify customer unethical behavior as a morally charged work demand that leads to a depletion of resources as captured by employee emotional exhaustion. In turn, emotionally exhausted employees experience higher levels of work-family conflict, relationship conflict with coworkers, and job neglect. Employee emotional exhaustion serves as the mediator between customer unethical behavior and such outcomes. To provide further evidence of a deontological effect, we demonstrate the unique effect of customer unethical behavior onto emotional exhaustion beyond perceptions of personal mistreatment and trait negative affectivity. In Study 1, we found support for our theoretical model using multisource field data from customer-service professionals across a variety of industries. In Study 2, we also found support for our theoretical model using multisource, longitudinal field data from service employees in a large government organization. Theoretical and practical implications are discussed. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

I know what you did last summer (and it was not CBT): a factor analytic model of international psychotherapeutic practice in the eating disorders.

PubMed

Tobin, David L; Banker, Judith D; Weisberg, Laura; Bowers, Wayne

2007-12-01

Although several studies have shown that eating disorders clinicians do not generally use treatment manuals, findings regarding what they do use have typically been vague, or closely linked to a particular theoretical approach. Our goal was to identify what eating disorder clinicians do with their patients in a more theoretically neutral context. We also sought to describe an empirically defined approach to psychotherapeutic practice as defined by clinicians via factor analysis. A survey developed for this study was administered to 265 clinicians recruited online and at regional and international meetings for eating disorders professionals. Only 6% of respondents reported they adhered closely to treatment manuals and 98% of the respondents indicated they used both behavioral and dynamically informed interventions. Factor analysis of clinicians' use of 32 therapeutic strategies suggested seven dimensions: Psychodynamic Interventions, Coping Skills Training, Family History, CBT, Contracts, Therapist Disclosure, and Patient Feelings. The findings of this study suggest that most clinicians use a wide array of eating disorder treatment interventions drawn from empirically supported treatments, such as CBT-BN, and from treatments that have no randomized controlled trial support. Factor analysis suggested theoretically linked dimensions of treatment, but also dimensions that are common across models. (c) 2007 by Wiley Periodicals, Inc.

Methodologic support in habilitation and rehabilitation: communicative action between practice and science.

PubMed

Iwarsson, S; Jernryd, E; Rutström, C; Boqvist, A

2000-01-01

This study evaluated the early phase of development of a model for quality improvement of habilitation and rehabilitation project processes. The focus of the methodologic support in habilitation and rehabilitation model was on cooperation between practice contexts and science. Habermas' theory about communicative action was a theoretical frame of reference. Three project coordinators and ten project leaders were interviewed. The results revealed different attitudes towards methodologic support activities, demonstrating the importance of acknowledging cognitive and social functions, the process of legitimization, different approaches of practice versus science, and problems regarding information and communication. The model was shown to be important in bridging the gap between practice and science. To support reflective and emancipatory cognitive learning, more efforts to foster communicative action are called for, and more attention must be paid to the importance different missions and organizational structures have for the development of the dialog between practitioners and researchers.

The impact of nursing work environments on patient safety outcomes: the mediating role of burnout/engagement.

PubMed

Spence Laschinger, Heather K; Leiter, Michael P

2006-05-01

To test a theoretical model of professional nurse work environments linking conditions for professional nursing practice to burnout and, subsequently, patient safety outcomes. The 2004 Institute of Medicine report raised serious concerns about the impact of hospital restructuring on nursing work environments and patient safety outcomes. Few studies have used a theoretical framework to study the nature of the relationships between nursing work environments and patient safety outcomes. Hospital-based nurses in Canada (N = 8,597) completed measures of worklife (Practice Environment Scale of the Nursing Work Index), burnout (Maslach Burnout Inventory-Human Service Scale), and their report of frequency of adverse patient events. Structural equation modeling analysis supported an extension of Leiter and Laschinger's Nursing Worklife Model. Nursing leadership played a fundamental role in the quality of worklife regarding policy involvement, staffing levels, support for a nursing model of care (vs medical), and nurse/physician relationships. Staffing adequacy directly affected emotional exhaustion, and use of a nursing model of care had a direct effect on nurses' personal accomplishment. Both directly affected patient safety outcomes. The results suggest that patient safety outcomes are related to the quality of the nursing practice work environment and nursing leadership's role in changing the work environment to decrease nurse burnout.

Traditional Arabic & Islamic medicine: validation and empirical assessment of a conceptual model in Qatar.

PubMed

AlRawi, Sara N; Khidir, Amal; Elnashar, Maha S; Abdelrahim, Huda A; Killawi, Amal K; Hammoud, Maya M; Fetters, Michael D

2017-03-14

Evidence indicates traditional medicine is no longer only used for the healthcare of the poor, its prevalence is also increasing in countries where allopathic medicine is predominant in the healthcare system. While these healing practices have been utilized for thousands of years in the Arabian Gulf, only recently has a theoretical model been developed illustrating the linkages and components of such practices articulated as Traditional Arabic & Islamic Medicine (TAIM). Despite previous theoretical work presenting development of the TAIM model, empirical support has been lacking. The objective of this research is to provide empirical support for the TAIM model and illustrate real world applicability. Using an ethnographic approach, we recruited 84 individuals (43 women and 41 men) who were speakers of one of four common languages in Qatar; Arabic, English, Hindi, and Urdu, Through in-depth interviews, we sought confirming and disconfirming evidence of the model components, namely, health practices, beliefs and philosophy to treat, diagnose, and prevent illnesses and/or maintain well-being, as well as patterns of communication about their TAIM practices with their allopathic providers. Based on our analysis, we find empirical support for all elements of the TAIM model. Participants in this research, visitors to major healthcare centers, mentioned using all elements of the TAIM model: herbal medicines, spiritual therapies, dietary practices, mind-body methods, and manual techniques, applied singularly or in combination. Participants had varying levels of comfort sharing information about TAIM practices with allopathic practitioners. These findings confirm an empirical basis for the elements of the TAIM model. Three elements, namely, spiritual healing, herbal medicine, and dietary practices, were most commonly found. Future research should examine the prevalence of TAIM element use, how it differs among various populations, and its impact on health.

Moving from reclusion to partial freedom: the experience of family caregivers for disabled elderly persons assisted in a day care center.

PubMed

Bocchi, Silvia Cristina Mangini; Cano, Karen Cristina Urtado; Baltieri, Lilian; Godoy, Daniele Cristina; Spiri, Wilza Carla; Juliani, Carmen Maria Casquel Monti

2010-09-01

This study aimed at understanding the interactional experience between family caregivers and disabled elderly persons supported in a Day Care Center according to the caregiver's perspective. It also aimed at developing a representative theoretical model for the events experienced by such caregiver. The Grounded Theory was used as methodological framework whereas Interactional Symbolism served as the theoretical framework. Observation and interviews were used for data collection. The following phenomenon arose from the results: feeling of support by the Day Care Center, by the strength of the bond with the elderly and by spirituality in order to continue playing the challenging role of a family caregiver for a disabled elderly person. The study made possible to understand that, among these three supporting cornerstones for coping with the burden generated by the family caregiver role, the care model promoted by the Day Care Center was the intervenient variable in the process of improving the quality of life of the family caregiver-disabled elderly person binomial. This allowed the identification of the main category--moving from reclusion to partial freedom: the experience of family caregivers for disabled elderly persons assisted in a Day Care Center.

Advancing engagement methods for trials: the CORE study relational model of engagement for a stepped wedge cluster randomised controlled trial of experience-based co-design for people living with severe mental illnesses.

PubMed

Richard, Lauralie; Piper, Donella; Weavell, Wayne; Callander, Rosemary; Iedema, Rick; Furler, John; Pierce, David; Godbee, Kali; Gunn, Jane; Palmer, Victoria J

2017-04-08

Engagement is essential in trials research but is rarely embedded across all stages of the research continuum. The development, use, effectiveness and value of engagement in trials research is poorly researched and understood, and models of engagement are rarely informed by theory. This article describes an innovative methodological approach for the development and application of a relational model of engagement in a stepped wedge designed cluster randomised controlled trial (RCT), the CORE study. The purpose of the model is to embed engagement across the continuum of the trial which will test if an experience-based co-design intervention improves psychosocial recovery for people affected by severe mental illness. The model was developed in three stages and used a structured iterative approach. A context mapping assessment of trial sites was followed by a literature review on recruitment and retention of hard-to-reach groups in complex interventions and RCTs. Relevant theoretical and philosophical underpinnings were identified by an additional review of literature to inform model development and enactment of engagement activities. Policy, organisational and service user data combined with evidence from the literature on barriers to recruitment provided contextual information. Four perspectives support the theoretical framework of the relational model of engagement and this is organised around two facets: the relational and continuous. The relational facet is underpinned by relational ethical theories and participatory action research principles. The continuous facet is supported by systems thinking and translation theories. These combine to enact an ethics of engagement and evoke knowledge mobilisation to reach the higher order goals of the model. Engagement models are invaluable for trials research, but there are opportunities to advance their theoretical development and application, particularly within stepped wedge designed studies where there may be a significant waiting period between enrolment in a study and receipt of an intervention.

Intention to quit and the role of dark personality and perceived organizational support: A moderation and mediation model.

PubMed

Treglown, Luke; Zivkov, Katarina; Zarola, Anthony; Furnham, Adrian

2018-01-01

This study investigated the role of individual differences (dark personality) and situational factors (perceived organisational support) in explaining intention to quit. Four hundred and fifty-one (50 of which females) ambulance personnel completed three questionnaires (Hogan Development Survey; Perceived Organisational Support Survey; and a single item Intention to Quit measure) as a part of a selection and development assessment. Employees high on Excitable, Sceptical, and Mischievous, but low on Colourful were found to have greater intentions to quit. Additionally, employees high on Excitable, Sceptical, Reserved, and Leisurely, but low on Dutiful and Diligent had lower perceptions of organisational support. Structural Equation Modelling revealed that perceived organisational support plays both a mediating and moderating role on dark personality and intention to quit. Theoretical implications of personality's role in perceived organisational support and intention to quit are discussed.

Intention to quit and the role of dark personality and perceived organizational support: A moderation and mediation model

PubMed Central

Zivkov, Katarina; Zarola, Anthony; Furnham, Adrian

2018-01-01

This study investigated the role of individual differences (dark personality) and situational factors (perceived organisational support) in explaining intention to quit. Four hundred and fifty-one (50 of which females) ambulance personnel completed three questionnaires (Hogan Development Survey; Perceived Organisational Support Survey; and a single item Intention to Quit measure) as a part of a selection and development assessment. Employees high on Excitable, Sceptical, and Mischievous, but low on Colourful were found to have greater intentions to quit. Additionally, employees high on Excitable, Sceptical, Reserved, and Leisurely, but low on Dutiful and Diligent had lower perceptions of organisational support. Structural Equation Modelling revealed that perceived organisational support plays both a mediating and moderating role on dark personality and intention to quit. Theoretical implications of personality’s role in perceived organisational support and intention to quit are discussed. PMID:29596532

Refinement of a Conceptual Model for Adolescent Readiness to Engage in End-of-Life Discussions.

PubMed

Bell, Cynthia J; Zimet, Gregory D; Hinds, Pamela S; Broome, Marion E; McDaniel, Anna M; Mays, Rose M; Champion, Victoria L

Adolescents living with incurable cancer require ongoing support to process grief, emotions, and information as disease progresses including treatment options (phase 1 clinical trials and/or hospice/palliative care). Little is known about how adolescents become ready for such discussions. The purpose of this study was to explore the process of adolescent readiness for end-of-life preparedness discussions, generating a theoretical understanding for guiding clinical conversations when curative options are limited. We explored 2 in-depth cases across time using case-study methodology. An à priori conceptual model based on current end-of-life research guided data collection and analysis. Multiple sources including in-depth adolescent interviews generated data collection on model constructs. Analysis followed a logical sequence establishing a chain of evidence linking raw data to study conclusions. Synthesis and data triangulation across cases and time led to theoretical generalizations. Initially, we proposed a linear process of readiness with 3 domains: a cognitive domain (awareness), an emotional domain (acceptance), and a behavioral domain (willingness), which preceded preparedness. Findings led to conceptual model refinement showing readiness is a dynamic internal process that interacts with preparedness. Current awareness context facilitates the type of preparedness discussions (cognitive or emotional). Furthermore, social constraint inhibits discussions. Data support theoretical understanding of the dynamism of readiness. Future research that validates adolescent conceptualization will ensure age-appropriate readiness representation. Understanding the dynamic process of readiness for engaging in end-of-life preparedness provides clinician insight for guiding discussions that facilitate shared decision making and promote quality of life for adolescents and their families.

Paternal/maternal attachment, peer support, social expectations of peer interaction, and depressive symptoms.

PubMed

Liu, Yih-Lan

2006-01-01

The aim of this study was to investigate how paternal and maternal attachment might relate to adolescents' peer support, social expectations of peer interaction, and depressive symptoms; 1,144 8th graders in Taiwan participated in the study. The relationships were examined through a structural equating modeling. Consistent with theoretical formulations, adolescents with secure attachments to parents reported higher peer support, fewer negative expectations, and fewer depressive symptoms. Paternal and maternal attachment contribute almost equally to adolescents' social expectations of peer interaction and depressive symptoms. Attachment to the same-sex parent was related to adolescents' perceived peer support.

Magnetic Guarding: Experimental and Numerical Results

NASA Astrophysics Data System (ADS)

Heinrich, Jonathon; Font, Gabriel; Garrett, Michael; Rose, D.; Genoni, T.; Welch, D.; McGuire, Thomas

2017-10-01

The magnetic field topology of Lockheed Martin's Compact Fusion Reactor (CFR) concept requires internal magnetic field coils. Internal coils for similar devices have leveraged levitating coils or coils with magnetically guarded supports. Magnetic guarding of supports has been investigated for multipole devices (theoretically and experimentally) without conclusive results. One outstanding question regarding magnetic guarding of supports is the magnitude and behavior of secondary plasma drifts resulting from magnetic guard fields (grad-B drifts, etc). We present magnetic-implicit PIC modeling results and preliminary proof of concept experimental results on magnetic guarding of internal-supports and the subsequent reduction in total plasma losses.

Representational Approach: A Conceptual Framework to Guide Patient Education Research and Practice.

PubMed

Arida, Janet A; Sherwood, Paula R; Flannery, Marie; Donovan, Heidi S

2016-11-01

Illness representations are cognitive structures that individuals rely on to understand and explain their illnesses and associated symptoms. The Representational Approach (RA) to patient education offers a theoretically based, clinically useful model that can support oncology nurses to develop a shared understanding of patients' illness representations to collaboratively develop highly personalized plans for symptom management and other important self-management behaviors. This article discusses theoretical underpinnings, practical applications, challenges, and future directions for incorporating illness representations and the RA in clinical and research endeavors.

Modelling Catalyst Surfaces Using DFT Cluster Calculations

PubMed Central

Czekaj, Izabela; Wambach, Jörg; Kröcher, Oliver

2009-01-01

We review our recent theoretical DFT cluster studies of a variety of industrially relevant catalysts such as TiO2, γ-Al2O3, V2O5-WO3-TiO2 and Ni/Al2O3. Aspects of the metal oxide surface structure and the stability and structure of metal clusters on the support are discussed as well as the reactivity of surfaces, including their behaviour upon poisoning. It is exemplarily demonstrated how such theoretical considerations can be combined with DRIFT and XPS results from experimental studies. PMID:20057947

Professional development for design-based learning in engineering education: a case study

NASA Astrophysics Data System (ADS)

Gómez Puente, Sonia M.; van Eijck, Michiel; Jochems, Wim

2015-01-01

Design-based learning (DBL) is an educational approach in which students gather and apply theoretical knowledge to solve design problems. In this study, we examined how critical DBL dimensions (project characteristics, design elements, the teacher's role, assessment, and social context) are applied by teachers in the redesign of DBL projects. We conducted an intervention for the professional development of the DBL teachers in the Mechanical Engineering and the Electrical Engineering departments. We used the Experiential Learning Cycle as an educational model for the professionalisation programme. The findings show that the programme encouraged teachers to apply the DBL theoretical framework. However, there are some limitations with regard to specific project characteristics. Further research into supporting teachers to develop open-ended and multidisciplinary activities in the projects that support learning is recommended.

Becoming Independent Storytellers: Modeling Children's Development of Narrative Macrostructure

ERIC Educational Resources Information Center

Kelly, Kimberly Reynolds; Bailey, Alison Louise

2013-01-01

For parents to provide effective support for their children's language development, they must be attuned to their child's changing abilities. This study presents a theoretically driven strategy that addresses a methodological challenge present when tracking longitudinally the cessation or "fading" of behaviors by capturing withdrawal of…

Developing a Network of and for Geometric Reasoning

ERIC Educational Resources Information Center

Mamolo, Ami; Ruttenberg-Rozen, Robyn; Whiteley, Walter

2015-01-01

In this article, we develop a theoretical model for restructuring mathematical tasks, usually considered advanced, with a network of spatial visual representations designed to support geometric reasoning for learners of disparate ages, stages, strengths, and preparation. Through our geometric reworking of the well-known "open box…

Contemporary Theories of Depression: Critique and Comparison

ERIC Educational Resources Information Center

Blaney, Paul H.

1977-01-01

Three theoretical viewpoints have dominated the recent empirically oriented literature on depression: Beck's cognitive view, Seligman's helplessness model, and Lewinsohn's theory implicating a low rate of response-contingent reinforcement. Here each theory is evaluated individually interms of its empirical support and adequacy as a theory and all…

Motivating Reading Comprehension: Concept-Oriented Reading Instruction

ERIC Educational Resources Information Center

Guthrie, John T., Ed.; Wigfield, Allan, Ed.; Perencevich, Kathleen C., Ed.

2004-01-01

Concept Oriented Reading Instruction (CORI) is a unique, classroom-tested model of reading instruction that breaks new ground by explicitly showing how content knowledge, reading strategies, and motivational support all merge in successful reading instruction. A theoretical perspective (engagement in reading) frames the book and provides a…

Differential School Contextual Effects for Math and English: Integrating the Big-Fish-Little-Pond Effect and the Internal/External Frame of Reference

ERIC Educational Resources Information Center

Parker, Philip D.; Marsh, Herbert W.; Ludtke, Oliver; Trautwein, Ulrich

2013-01-01

The internal/external frame of reference and the big-fish-little-pond effect are two major models of academic self-concept formation which have considerable theoretical and empirical support. Integrating the domain specific and compensatory processes of the internal/external frame of reference model with the big-fish-little-pond effect suggests a…

Lump Solitons in Surface Tension Dominated Flows

NASA Astrophysics Data System (ADS)

Milewski, Paul; Berger, Kurt

1999-11-01

The Kadomtsev-Petviashvilli I equation (KPI) which models small-amplitude, weakly three-dimensional surface-tension dominated long waves is integrable and allows for algebraically decaying lump solitary waves. It is not known (theoretically or numerically) whether the full free-surface Euler equations support such solutions. We consider an intermediate model, the generalised Benney-Luke equation (gBL) which is isotropic (not weakly three-dimensional) and contains KPI as a limit. We show numerically that: 1. gBL supports lump solitary waves; 2. These waves collide elastically and are stable; 3. They are generated by resonant flow over an obstacle.

Processes of behavior change and weight loss in a theory-based weight loss intervention program: a test of the process model for lifestyle behavior change.

PubMed

Gillison, Fiona; Stathi, Afroditi; Reddy, Prasuna; Perry, Rachel; Taylor, Gordon; Bennett, Paul; Dunbar, James; Greaves, Colin

2015-01-16

Process evaluation is important for improving theories of behavior change and behavioral intervention methods. The present study reports on the process outcomes of a pilot test of the theoretical model (the Process Model for Lifestyle Behavior Change; PMLBC) underpinning an evidence-informed, theory-driven, group-based intervention designed to promote healthy eating and physical activity for people with high cardiovascular risk. 108 people at high risk of diabetes or heart disease were randomized to a group-based weight management intervention targeting diet and physical activity plus usual care, or to usual care. The intervention comprised nine group based sessions designed to promote motivation, social support, self-regulation and understanding of the behavior change process. Weight loss, diet, physical activity and theoretically defined mediators of change were measured pre-intervention, and after four and 12 months. The intervention resulted in significant improvements in fiber intake (M between-group difference = 5.7 g/day, p < .001) but not fat consumption (-2.3 g/day, p = 0.13), that were predictive of weight loss at both four months (M between-group difference = -1.98 kg, p < .01; R(2) = 0.2, p < 0.005), and 12 months (M difference = -1.85 kg, p = 0.1; R(2) = 0.1, p < 0.01). The intervention was successful in improving the majority of specified mediators of behavior change, and the predicted mechanisms of change specified in the PMBLC were largely supported. Improvements in self-efficacy and understanding of the behavior change process were associated with engagement in coping planning and self-monitoring activities, and successful dietary change at four and 12 months. While participants reported improvements in motivational and social support variables, there was no effect of these, or of the intervention overall, on physical activity. The data broadly support the theoretical model for supporting some dietary changes, but not for physical activity. Systematic intervention design allowed us to identify where improvements to the intervention may be implemented to promote change in all proposed mediators. More work is needed to explore effective mechanisms within interventions to promote physical activity behavior.

The Animadora Project: Identifying factors related to the promotion of physical activity among Mexican Americans with diabetes

PubMed Central

Ingram, Maia; Ruis, Maricruz; Mayorga, Maria Theresa; Rosales, Cecilia

2015-01-01

Purpose There is a dearth of information about factors related to physical activity among Mexican Americans with diabetes. Self efficacy and social support are associated with physical activity, however little is known about their role within different cultural groups. Design Focus groups were used to identify factors that motivate walking. Setting Two Mexican American communities located in Tucson, Arizona. Subjects Individuals who attended diabetes education. Intervention A community-based provider organized walking groups with people who previously attended diabetes classes. Walkers participated in focus groups exploring themes related to their experience. Measures Self efficacy, social support, and collective efficacy. Grounded theory was used to analyze focus group results using two rounds of analysis; the first identifying references to self efficacy and social support and the second adding collective efficacy as a theoretical basis for walking. Results Among 43 eligible participants, 20 participated in focus groups. Social support was expressed as commitment and companionship. Walkers demonstrated a high level of self efficacy for walking. Development of group identity/social cohesion was also a motivator to walk. Collective efficacy emerged as an applicable theoretical model encompassing these themes and their interrelationship. Conclusion Collective efficacy, or the belief that the group can improve their lives through collective effort, is a viable theoretical construct in the development of physical activity interventions targeting Mexican Americans with diabetes. PMID:19601479

Modeling Kelvin Wave Cascades in Superfluid Helium

NASA Astrophysics Data System (ADS)

Boffetta, G.; Celani, A.; Dezzani, D.; Laurie, J.; Nazarenko, S.

2009-09-01

We study two different types of simplified models for Kelvin wave turbulence on quantized vortex lines in superfluids near zero temperature. Our first model is obtained from a truncated expansion of the Local Induction Approximation (Truncated-LIA) and it is shown to possess the same scalings and the essential behaviour as the full Biot-Savart model, being much simpler than the later and, therefore, more amenable to theoretical and numerical investigations. The Truncated-LIA model supports six-wave interactions and dual cascades, which are clearly demonstrated via the direct numerical simulation of this model in the present paper. In particular, our simulations confirm presence of the weak turbulence regime and the theoretically predicted spectra for the direct energy cascade and the inverse wave action cascade. The second type of model we study, the Differential Approximation Model (DAM), takes a further drastic simplification by assuming locality of interactions in k-space via using a differential closure that preserves the main scalings of the Kelvin wave dynamics. DAMs are even more amenable to study and they form a useful tool by providing simple analytical solutions in the cases when extra physical effects are present, e.g. forcing by reconnections, friction dissipation and phonon radiation. We study these models numerically and test their theoretical predictions, in particular the formation of the stationary spectra, and closeness of numerics for the higher-order DAM to the analytical predictions for the lower-order DAM.

Rheological properties of simulated debris flows in the laboratory environment

USGS Publications Warehouse

Ling, Chi-Hai; Chen, Cheng-lung; Jan, Chyan-Deng; ,

1990-01-01

Steady debris flows with or without a snout are simulated in a 'conveyor-belt' flume using dry glass spheres of a uniform size, 5 or 14 mm in diameter, and their rheological properties described quantitatively in constants in a generalized viscoplastic fluid (GVF) model. Close agreement of the measured velocity profiles with the theoretical ones obtained from the GVF model strongly supports the validity of a GVF model based on the continuum-mechanics approach. Further comparisons of the measured and theoretical velocity profiles along with empirical relations among the shear stress, the normal stress, and the shear rate developed from the 'ring-shear' apparatus determine the values of the rheological parameters in the GVF model, namely the flow-behavior index, the consistency index, and the cross-consistency index. Critical issues in the evaluation of such rheological parameters using the conveyor-belt flume and the ring-shear apparatus are thus addressed in this study.

Simulations of molecular self-assembled monolayers on surfaces: packing structures, formation processes and functions tuned by intermolecular and interfacial interactions.

PubMed

Wen, Jin; Li, Wei; Chen, Shuang; Ma, Jing

2016-08-17

Surfaces modified with a functional molecular monolayer are essential for the fabrication of nano-scale electronics or machines with novel physical, chemical, and/or biological properties. Theoretical simulation based on advanced quantum chemical and classical models is at present a necessary tool in the development, design, and understanding of the interfacial nanostructure. The nanoscale surface morphology, growth processes, and functions are controlled by not only the electronic structures (molecular energy levels, dipole moments, polarizabilities, and optical properties) of building units but also the subtle balance between intermolecular and interfacial interactions. The switchable surfaces are also constructed by introducing stimuli-responsive units like azobenzene derivatives. To bridge the gap between experiments and theoretical models, opportunities and challenges for future development of modelling of ferroelectricity, entropy, and chemical reactions of surface-supported monolayers are also addressed. Theoretical simulations will allow us to obtain important and detailed information about the structure and dynamics of monolayer modified interfaces, which will guide the rational design and optimization of dynamic interfaces to meet challenges of controlling optical, electrical, and biological functions.

Structural relaxation in supercooled orthoterphenyl.

PubMed

Chong, S-H; Sciortino, F

2004-05-01

We report molecular-dynamics simulation results performed for a model of molecular liquid orthoterphenyl in supercooled states, which we then compare with both experimental data and mode-coupling-theory (MCT) predictions, aiming at a better understanding of structural relaxation in orthoterphenyl. We pay special attention to the wave number dependence of the collective dynamics. It is shown that the simulation results for the model share many features with experimental data for real system, and that MCT captures the simulation results at the semiquantitative level except for intermediate wave numbers connected to the overall size of the molecule. Theoretical results at the intermediate wave number region are found to be improved by taking into account the spatial correlation of the molecule's geometrical center. This supports the idea that unusual dynamical properties at the intermediate wave numbers, reported previously in simulation studies for the model and discernible in coherent neutron-scattering experimental data, are basically due to the coupling of the rotational motion to the geometrical-center dynamics. However, there still remain qualitative as well as quantitative discrepancies between theoretical prediction and corresponding simulation results at the intermediate wave numbers, which call for further theoretical investigation.

Tapered fiber optic applicator for laser ablation: Theoretical and experimental assessment of thermal effects on ex vivo model.

PubMed

Saccomandi, P; Di Matteo, F M; Schena, E; Quero, G; Massaroni, C; Giurazza, F; Costamagna, G; Silvestri, S

2017-07-01

Laser Ablation (LA) is a minimally invasive technique for tumor removal. The laser light is guided into the target tissue by a fiber optic applicator; thus the physical features of the applicator tip strongly influence size and shape of the tissue lesion. This study aims to verify the geometry of the lesion achieved by a tapered-tip applicator, and to investigate the percentage of thermally damaged cells induced by the tapered-tip fiber optic applicator. A theoretical model was implemented to simulate: i) the distribution of laser light fluence rate in the tissue through Monte Carlo method, ii) the induced temperature distribution, by means of the Bio Heat Equation, iii) the tissue injury, by Arrhenius integral. The results obtained by the implementation of the theoretical model were experimentally assessed. Ex vivo porcine liver underwent LA with tapered-tip applicator, at different laser settings (laser power of 1 W and 1.7 W, deposited energy equal to 330 J and 500 J, respectively). Almost spherical volume lesions were produced. The thermal damage was assessed by measuring the diameter of the circular-shaped lesion. The comparison between experimental results and theoretical prediction shows that the thermal damage discriminated by visual inspection always corresponds to a percentage of damaged cells of 96%. A tapered-tip applicator allows obtaining localized and reproducible damage close to spherical shape, whose diameter is related to the laser settings, and the simple theoretical model described is suitable to predict the effects, in terms of thermal damage, on ex vivo liver. Further trials should be addressed to adapt the model also on in vivo tissue, aiming to develop a tool useful to support the physician in clinical application of LA.

Response to "Transfer or Specificity?"

ERIC Educational Resources Information Center

Miller, Judith

2007-01-01

This article presents the author's response to "Transfer or Specificity?" and reports a research that supports a strong case for a fundamental motor skill as a precursor to two sport specific skills as in Gallahue and Ozmun's (2002) theoretical model of motor development. Reported changes in performance of the overarm throw are…

The Study of Aggressive Pornography: The Vicissitudes of Relevance.

ERIC Educational Resources Information Center

Brannigan, Augustine; Goldenberg, Sheldon

1987-01-01

Reviews experimental studies of behavioral consequences of exposure to violent or aggressive pornography and evaluates the validity and relevance as support for censoring pornography in the aftermath of the Meese Commission. Finds research deficient in several areas, such as design, theoretical models, and interpretation, thus offering no…

Communication Privacy Disclosure Management: An Empirical Study of Socialization Support in a Pseudo-Online Course

ERIC Educational Resources Information Center

Heo, Misook

2011-01-01

This study investigated the boundaries of online learners' information disclosure, relationship building, interpersonal integration, and motivation by drawing upon the theoretical frameworks of the social information processing and communication privacy management theories and the hyperpersonal model. A total of 103 students from a higher…

Affect Regulation as a Mediator of Attachment and Deliberate Self-Harm

ERIC Educational Resources Information Center

Kimball, Joan S.; Diddams, Margaret

2007-01-01

The authors used structural equation modeling to test the mediational role of affect regulation on attachment and deliberate self-harm in 216 undergraduates. Results suggest that affect regulation mediates the relationship between attachment and deliberate self-harm, providing support for the theoretical importance of attachment and affect…

The Intersectional Matrix: Rethinking Institutional Change for URM Women in STEM

ERIC Educational Resources Information Center

Armstrong, Mary A.; Jovanovic, Jasna

2017-01-01

This article investigates the persistent challenge of how higher education institutions can support the success of underrepresented minority (URM) women in science, technology, engineering, and mathematics (STEM) fields. Our theoretical model centers on intersectionality, and we examine the possibilities and challenges involved in taking an…

Theoretical Bases for Using Virtual Reality in Education

ERIC Educational Resources Information Center

Chen, Chwen Jen

2009-01-01

This article elaborates on how the technical capabilities of virtual reality support the constructivist learning principles. It introduces VRID, a model for instructional design and development that offers explicit guidance on how to produce an educational virtual environment. The define phase of VRID consists of three main tasks: forming a…

Fatigue-life distributions for reaction time data.

PubMed

Tejo, Mauricio; Niklitschek-Soto, Sebastián; Marmolejo-Ramos, Fernando

2018-06-01

The family of fatigue-life distributions is introduced as an alternative model of reaction time data. This family includes the shifted Wald distribution and a shifted version of the Birnbaum-Saunders distribution. Although the former has been proposed as a way to model reaction time data, the latter has not. Hence, we provide theoretical, mathematical and practical arguments in support of the shifted Birnbaum-Saunders as a suitable model of simple reaction times and associated cognitive mechanisms.

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

NASA Astrophysics Data System (ADS)

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.

Confirmatory Factor Analysis of the Combined Social Phobia Scale and Social Interaction Anxiety Scale: Support for a Bifactor Model.

PubMed

Gomez, Rapson; Watson, Shaun D

2017-01-01

For the Social Phobia Scale (SPS) and the Social Interaction Anxiety Scale (SIAS) together, this study examined support for a bifactor model, and also the internal consistency reliability and external validity of the factors in this model. Participants ( N = 526) were adults from the general community who completed the SPS and SIAS. Confirmatory factor analysis (CFA) of their ratings indicated good support for the bifactor model. For this model, the loadings for all but six items were higher on the general factor than the specific factors. The three positively worded items had negligible loadings on the general factor. The general factor explained most of the common variance in the SPS and SIAS, and demonstrated good model-based internal consistency reliability (omega hierarchical) and a strong association with fear of negative evaluation and extraversion. The practical implications of the findings for the utilization of the SPS and SIAS, and the theoretical and clinical implications for social anxiety are discussed.

Confirmatory Factor Analysis of the Combined Social Phobia Scale and Social Interaction Anxiety Scale: Support for a Bifactor Model

PubMed Central

Gomez, Rapson; Watson, Shaun D.

2017-01-01

For the Social Phobia Scale (SPS) and the Social Interaction Anxiety Scale (SIAS) together, this study examined support for a bifactor model, and also the internal consistency reliability and external validity of the factors in this model. Participants (N = 526) were adults from the general community who completed the SPS and SIAS. Confirmatory factor analysis (CFA) of their ratings indicated good support for the bifactor model. For this model, the loadings for all but six items were higher on the general factor than the specific factors. The three positively worded items had negligible loadings on the general factor. The general factor explained most of the common variance in the SPS and SIAS, and demonstrated good model-based internal consistency reliability (omega hierarchical) and a strong association with fear of negative evaluation and extraversion. The practical implications of the findings for the utilization of the SPS and SIAS, and the theoretical and clinical implications for social anxiety are discussed. PMID:28210232

Self-efficacy and health-related quality of life in family carers of people with dementia: a systematic review

PubMed Central

Crellin, Nadia E.; Orrell, Martin; McDermott, Orii; Charlesworth, Georgina

2014-01-01

Objectives: This review aims to explore the role of self-efficacy (SE) in the health-related quality of life (QoL) of family carers of people with dementia. Methods: A systematic review of literature identified a range of qualitative and quantitative studies. Search terms related to caring, SE, and dementia. Narrative synthesis was adopted to synthesise the findings. Results: Twenty-two studies met the full inclusion criteria, these included 17 quantitative, four qualitative, and one mixed-method study. A model describing the role of task/domain-specific SE beliefs in family carer health-related QoL was constructed. This model was informed by review findings and discussed in the context of existing conceptual models of carer adaptation and empirical research. Review findings offer support for the application of the SE theory to caring and for the two-factor view of carer appraisals and well-being. Findings do not support the independence of the negative and positive pathways. The review was valuable in highlighting methodological challenges confronting this area of research, particularly the conceptualisation and measurement issues surrounding both SE and health-related QoL. Conclusions: The model might have theoretical implications in guiding future research and advancing theoretical models of caring. It might also have clinical implications in facilitating the development of carer support services aimed at improving SE. The review highlights the need for future research, particularly longitudinal research, and further exploration of domain/task-specific SE beliefs, the influence of carer characteristics, and other mediating/moderating variables. PMID:24943873

Exploring the relation between masculinity and mental illness stigma using the stereotype content model and BIAS map.

PubMed

Boysen, Guy A

2017-01-01

The current research explored the association of masculinity and stigma toward mental illness using theoretical predictions stemming from the stereotype content model and BIAS map. Two correlational studies (Ns = 245, 163) measured stereotypes, emotions, and behavioral intentions in relation to masculine, feminine, and gender-neutral disorders. Participants perceived masculine disorders as lacking personal warmth and competence. Masculine disorders also elicited more negative emotions and behavioral intentions. Two experimental studies (Ns = 161, 431) manipulated personal warmth, sex, and type of disorder in descriptions of people with mental illness. Low warmth and stereotypically masculine disorders consistently elicited negative emotions and behavioral intentions, but sex had limited effects. Overall, the results supported the theoretical models and illustrated the importance of warmth and symptomatic behavior in explaining the masculinity-stigma relation.

A social exchange-based model of the antecedents of workplace exclusion.

PubMed

Scott, Kristin L; Restubog, Simon Lloyd D; Zagenczyk, Thomas J

2013-01-01

We conducted 2 studies of coworker dyads to test a theoretical model exploring why and under what circumstances employees are the targets of workplace exclusion. Adopting a victim precipitation perspective, we integrate belongingness and social exchange theories to propose that employees who display workplace incivility are distrusted and therefore are targets of workplace exclusion. Highlighting the importance of the context of the perpetrator-target relationship, we also find support for the postulation that this mediated relationship is strengthened when the target employee is perceived to be a weak exchange partner and is attenuated when he or she is viewed as a valuable exchange partner. Theoretical and practical implications are discussed. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Supportive accountability: a model for providing human support to enhance adherence to eHealth interventions.

PubMed

Mohr, David C; Cuijpers, Pim; Lehman, Kenneth

2011-03-10

The effectiveness of and adherence to eHealth interventions is enhanced by human support. However, human support has largely not been manualized and has usually not been guided by clear models. The objective of this paper is to develop a clear theoretical model, based on relevant empirical literature, that can guide research into human support components of eHealth interventions. A review of the literature revealed little relevant information from clinical sciences. Applicable literature was drawn primarily from organizational psychology, motivation theory, and computer-mediated communication (CMC) research. We have developed a model, referred to as "Supportive Accountability." We argue that human support increases adherence through accountability to a coach who is seen as trustworthy, benevolent, and having expertise. Accountability should involve clear, process-oriented expectations that the patient is involved in determining. Reciprocity in the relationship, through which the patient derives clear benefits, should be explicit. The effect of accountability may be moderated by patient motivation. The more intrinsically motivated patients are, the less support they likely require. The process of support is also mediated by the communications medium (eg, telephone, instant messaging, email). Different communications media each have their own potential benefits and disadvantages. We discuss the specific components of accountability, motivation, and CMC medium in detail. The proposed model is a first step toward understanding how human support enhances adherence to eHealth interventions. Each component of the proposed model is a testable hypothesis. As we develop viable human support models, these should be manualized to facilitate dissemination.

Mechanism change in a simulation of peer review: from junk support to elitism.

PubMed

Paolucci, Mario; Grimaldo, Francisco

2014-01-01

Peer review works as the hinge of the scientific process, mediating between research and the awareness/acceptance of its results. While it might seem obvious that science would regulate itself scientifically, the consensus on peer review is eroding; a deeper understanding of its workings and potential alternatives is sorely needed. Employing a theoretical approach supported by agent-based simulation, we examined computational models of peer review, performing what we propose to call redesign , that is, the replication of simulations using different mechanisms . Here, we show that we are able to obtain the high sensitivity to rational cheating that is present in literature. In addition, we also show how this result appears to be fragile against small variations in mechanisms. Therefore, we argue that exploration of the parameter space is not enough if we want to support theoretical statements with simulation, and that exploration at the level of mechanisms is needed. These findings also support prudence in the application of simulation results based on single mechanisms, and endorse the use of complex agent platforms that encourage experimentation of diverse mechanisms.

Practical Findings from Applying the PSD Model for Evaluating Software Design Specifications

NASA Astrophysics Data System (ADS)

Räisänen, Teppo; Lehto, Tuomas; Oinas-Kukkonen, Harri

This paper presents practical findings from applying the PSD model to evaluating the support for persuasive features in software design specifications for a mobile Internet device. On the one hand, our experiences suggest that the PSD model fits relatively well for evaluating design specifications. On the other hand, the model would benefit from more specific heuristics for evaluating each technique to avoid unnecessary subjectivity. Better distinction between the design principles in the social support category would also make the model easier to use. Practitioners who have no theoretical background can apply the PSD model to increase the persuasiveness of the systems they design. The greatest benefit of the PSD model for researchers designing new systems may be achieved when it is applied together with a sound theory, such as the Elaboration Likelihood Model. Using the ELM together with the PSD model, one may increase the chances for attitude change.

Surface tension driven flow in glass melts and model fluids

NASA Technical Reports Server (NTRS)

Mcneil, T. J.; Cole, R.; Subramanian, R. S.

1982-01-01

Surface tension driven flow has been investigated analytically and experimentally using an apparatus where a free column of molten glass or model fluids was supported at its top and bottom faces by solid surfaces. The glass used in the experiments was sodium diborate, and the model fluids were silicone oils. In both the model fluid and glass melt experiments, conclusive evidence was obtained to prove that the observed flow was driven primarily by surface tension forces. The experimental observations are in qualitative agreement with predictions from the theoretical model.

Internalized stigma and quality of life domains among people with mental illness: the mediating role of self-esteem.

PubMed

Oliveira, Sandra E H; Carvalho, Helena; Esteves, Francisco

2016-01-01

People with mental illness who internalize stigma often experience reduced self-esteem and impaired quality of life (QOL). To propose a theoretical model in which self-esteem mediates the effects of internalized stigma on the multidimensional domains comprising QOL. In 403 inpatients and outpatients (DSM-IV, American Psychiatric Association, 1994), from hospital-based and community mental health facilities, self-report measures of internalized stigma (ISMI), self-esteem (RSES) and QOL (WHOQOL-Bref) were administrated. Structural equation modeling results supported the proposed model. Self-esteem fully mediated the relation between internalized stigma and the physical and the social relationships domains, and partially mediated the relationship between internalized stigma and psychological, environment and level of independence QOL domains. Such results provided empirical support and shed light upon previous research. Specifically the results emphasize the mediating role that self-esteem plays in the degree to which internalized stigma exerts a negative effect on specific QOL domains. Self-esteem appears to be a core element in reducing the negative effects of internalized stigma on aspects of QOL among people with mental illness. These findings suggest there is a crucial impact regarding clinical mental health interventions along with important theoretical implications.

Modeling Exoplanetary Haze and Cloud Effects for Transmission Spectroscopy in the TRAPPIST-1 System

NASA Astrophysics Data System (ADS)

Moran, Sarah E.; Horst, Sarah M.; Lewis, Nikole K.; Batalha, Natasha E.; de Wit, Julien

2018-01-01

We present theoretical transmission spectra of the planets TRAPPIST-1d, e, f, and g using a version of the CaltecH Inverse ModEling and Retrieval Algorithms (CHIMERA) atmospheric modeling code. We use particle size, aerosol production rates, and aerosol composition inputs from recent laboratory experiments relevant for the TRAPPIST-1 system to constrain cloud and haze behavior and their effects on transmission spectra. We explore these cloud and haze cases for a variety of theoretical atmospheric compositions including hydrogen-, nitrogen-, and carbon dioxide-dominated atmospheres. Then, we demonstrate the feasibility of physically-motivated, laboratory-supported clouds and hazes to obscure spectral features at wavelengths and resolutions relevant to instruments on the Hubble Space Telescope and the upcoming James Webb Space Telescope. Lastly, with laboratory based constraints of haze production rates for terrestrial exoplanets, we constrain possible bulk atmospheric compositions of the TRAPPIST-1 planets based on current observations. We show that continued collection of optical data, beyond the supported wavelength range of the James Webb Telescope, is necessary to explore the full effect of hazes for transmission spectra of exoplanetary atmospheres like the TRAPPIST-1 system.

Realization of Rectangular Artificial Spin Ice and Direct Observation of High Energy Topology.

PubMed

Ribeiro, I R B; Nascimento, F S; Ferreira, S O; Moura-Melo, W A; Costa, C A R; Borme, J; Freitas, P P; Wysin, G M; de Araujo, C I L; Pereira, A R

2017-10-25

In this work, we have constructed and experimentally investigated frustrated arrays of dipoles forming two-dimensional artificial spin ices with different lattice parameters (rectangular arrays with horizontal and vertical lattice spacings denoted by a and b respectively). Arrays with three different aspect ratios γ = a/b = [Formula: see text], [Formula: see text] and [Formula: see text] are studied. Theoretical calculations of low-energy demagnetized configurations for these same parameters are also presented. Experimental data for demagnetized samples confirm most of the theoretical results. However, the highest energy topology (doubly-charged monopoles) does not emerge in our theoretical model, while they are seen in experiments for large enough γ. Our results also insinuate that the string tension connecting two magnetic monopoles in a pair vanishes in rectangular lattices with a critical ratio γ = γ c  = [Formula: see text], supporting previous theoretical predictions.

The assumption of equilibrium in models of migration.

PubMed

Schachter, J; Althaus, P G

1993-02-01

In recent articles Evans (1990) and Harrigan and McGregor (1993) (hereafter HM) scrutinized the equilibrium model of migration presented in a 1989 paper by Schachter and Althaus. This model used standard microeconomics to analyze gross interregional migration flows based on the assumption that gross flows are in approximate equilibrium. HM criticized the model as theoretically untenable, while Evans summoned empirical as well as theoretical objections. HM claimed that equilibrium of gross migration flows could be ruled out on theoretical grounds. They argued that the absence of net migration requires that either all regions have equal populations or that unsustainable regional migration propensities must obtain. In fact some moves are inter- and other are intraregional. It does not follow, however, that the number of interregional migrants will be larger for the more populous region. Alternatively, a country could be divided into a large number of small regions that have equal populations. With uniform propensities to move, each of these analytical regions would experience in equilibrium zero net migration. Hence, the condition that net migration equal zero is entirely consistent with unequal distributions of population across regions. The criticisms of Evans were based both on flawed reasoning and on misinterpretation of the results of a number of econometric studies. His reasoning assumed that the existence of demand shifts as found by Goldfarb and Yezer (1987) and Topel (1986) invalidated the equilibrium model. The equilibrium never really obtains exactly, but economic modeling of migration properly begins with a simple equilibrium model of the system. A careful reading of the papers Evans cited in support of his position showed that in fact they affirmed rather than denied the appropriateness of equilibrium modeling. Zero net migration together with nonzero gross migration are not theoretically incompatible with regional heterogeneity of population, wages, or amenities.

Factors influencing nurse-assessed quality nursing care: A cross-sectional study in hospitals.

PubMed

Liu, Ying; Aungsuroch, Yupin

2018-04-01

To propose a hypothesized theoretical model and apply it to examine the structural relationships among work environment, patient-to-nurse ratio, job satisfaction, burnout, intention to leave and quality nursing care. Improving quality nursing care is a first consideration in nursing management globally. A better understanding of factors influencing quality nursing care can help hospital administrators implement effective programmes to improve quality of services. Although certain bivariate correlations have been found between selected factors and quality nursing care in different study models, no studies have examined the relationships among work environment, patient-to-nurse ratio, job satisfaction, burnout, intention to leave and quality nursing care in a more comprehensive theoretical model. A cross-sectional survey. The questionnaires were collected from 510 Chinese nurses in four Chinese tertiary hospitals in January 2015. The validity and internal consistency reliability of research instruments were evaluated. Structural equation modelling was used to test a theoretical model. The findings revealed that the data supported the theoretical model. Work environment had a large total effect size on quality nursing care. Burnout largely and directly influenced quality nursing care, which was followed by work environment and patient-to-nurse ratio. Job satisfaction indirectly affected quality nursing care through burnout. This study shows how work environment past burnout and job satisfaction influences quality nursing care. Apart from nurses' work conditions of work environment and patient-to-nurse ratio, hospital administrators should pay more attention to nurse outcomes of job satisfaction and burnout when designing intervention programmes to improve quality nursing care. © 2017 John Wiley & Sons Ltd.

Chromatin conformation in living cells: support for a zig-zag model of the 30 nm chromatin fiber

NASA Technical Reports Server (NTRS)

Rydberg, B.; Holley, W. R.; Mian, I. S.; Chatterjee, A.

1998-01-01

A new method was used to probe the conformation of chromatin in living mammalian cells. The method employs ionizing radiation and is based on the concept that such radiation induces correlated breaks in DNA strands that are in spatial proximity. Human dermal fibroblasts in G0 phase of the cell cycle and Chinese hamster ovary cells in mitosis were irradiated by X-rays or accelerated ions. Following lysis of the cells, DNA fragments induced by correlated breaks were end-labeled and separated according to size on denaturing polyacrylamide gels. A characteristic peak was obtained for a fragment size of 78 bases, which is the size that corresponds to one turn of DNA around the nucleosome. Additional peaks between 175 and 450 bases reflect the relative position of nearest-neighbor nucleosomes. Theoretical calculations that simulate the indirect and direct effect of radiation on DNA demonstrate that the fragment size distributions are closely related to the chromatin structure model used. Comparison of the experimental data with theoretical results support a zig-zag model of the chromatin fiber rather than a simple helical model. Thus, radiation-induced damage analysis can provide information on chromatin structure in the living cell. Copyright 1998 Academic Press.

Physics and Novel Schemes of Laser Radiation Pressure Acceleration for Quasi-monoenergetic Proton Generation

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

Liu, Chuan S.; Shao, Xi

2016-06-14

The main objective of our work is to provide theoretical basis and modeling support for the design and experimental setup of compact laser proton accelerator to produce high quality proton beams tunable with energy from 50 to 250 MeV using short pulse sub-petawatt laser. We performed theoretical and computational studies of energy scaling and Raleigh--Taylor instability development in laser radiation pressure acceleration (RPA) and developed novel RPA-based schemes to remedy/suppress instabilities for high-quality quasimonoenergetic proton beam generation as we proposed. During the project period, we published nine peer-reviewed journal papers and made twenty conference presentations including six invited talks onmore » our work. The project supported one graduate student who received his PhD degree in physics in 2013 and supported two post-doctoral associates. We also mentored three high school students and one undergraduate student of physics major by inspiring their interests and having them involved in the project.« less

The design of patient decision support interventions: addressing the theory-practice gap.

PubMed

Elwyn, Glyn; Stiel, Mareike; Durand, Marie-Anne; Boivin, Jacky

2011-08-01

Although an increasing number of decision support interventions for patients (including decision aids) are produced, few make explicit use of theory. We argue the importance of using theory to guide design. The aim of this work was to address this theory-practice gap and to examine how a range of selected decision-making theories could inform the design and evaluation of decision support interventions. We reviewed the decision-making literature and selected relevant theories. We assessed their key principles, theoretical pathways and predictions in order to determine how they could inform the design of two core components of decision support interventions, namely, information and deliberation components and to specify theory-based outcome measures. Eight theories were selected: (1) the expected utility theory; (2) the conflict model of decision making; (3) prospect theory; (4) fuzzy-trace theory; (5) the differentiation and consolidation theory; (6) the ecological rationality theory; (7) the rational-emotional model of decision avoidance; and finally, (8) the Attend, React, Explain, Adapt model of affective forecasting. Some theories have strong relevance to the information design (e.g. prospect theory); some are more relevant to deliberation processes (conflict theory, differentiation theory and ecological validity). None of the theories in isolation was sufficient to inform the design of all the necessary components of decision support interventions. It was also clear that most work in theory-building has focused on explaining or describing how humans think rather than on how tools could be designed to help humans make good decisions. It is not surprising therefore that a large theory-practice gap exists as we consider decision support for patients. There was no relevant theory that integrated all the necessary contributions to the task of making good decisions in collaborative interactions. Initiatives such as the International Patient Decision Aids Standards Collaboration influence standards for the design of decision support interventions. However, this analysis points to the need to undertake more work in providing theoretical foundations for these interventions. © 2010 Blackwell Publishing Ltd.

Experimental and theoretical NMR and IR studies of the side-chain orientation effects on the backbone conformation of dehydrophenylalanine residue.

PubMed

Buczek, Aneta M; Ptak, Tomasz; Kupka, Teobald; Broda, Małgorzata A

2011-06-01

Conformation of N-acetyl-(E)-dehydrophenylalanine N', N'-dimethylamide (Ac-(E)-ΔPhe-NMe(2)) in solution, a member of (E)-α, β-dehydroamino acids, was studied by NMR and infrared spectroscopy and the results were compared with those obtained for (Z) isomer. To support the spectroscopic interpretation, the Φ, Ψ potential energy surfaces were calculated at the MP2/6-31 + G(d,p) level of theory in chloroform solution modeled by the self-consistent reaction field-polarizable continuum model method. All minima were fully optimized by the MP2 method and their relative stabilities were analyzed in terms of π-conjugation, internal H-bonds and dipole interactions between carbonyl groups. The obtained NMR spectral features were compared with theoretical nuclear magnetic shieldings, calculated using Gauge Independent Atomic Orbitals (GIAO) approach and rescaled to theoretical chemical shifts using benzene as reference. The calculated indirect nuclear spin-spin coupling constants were compared with available experimental parameters. Copyright © 2011 John Wiley & Sons, Ltd.

Dynamic properties of molecular motors in burnt-bridge models

NASA Astrophysics Data System (ADS)

Artyomov, Maxim N.; Morozov, Alexander Yu; Pronina, Ekaterina; Kolomeisky, Anatoly B.

2007-08-01

Dynamic properties of molecular motors that fuel their motion by actively interacting with underlying molecular tracks are studied theoretically via discrete-state stochastic 'burnt-bridge' models. The transport of the particles is viewed as an effective diffusion along one-dimensional lattices with periodically distributed weak links. When an unbiased random walker passes the weak link it can be destroyed ('burned') with probability p, providing a bias in the motion of the molecular motor. We present a theoretical approach that allows one to calculate exactly all dynamic properties of motor proteins, such as velocity and dispersion, under general conditions. It is found that dispersion is a decreasing function of the concentration of bridges, while the dependence of dispersion on the burning probability is more complex. Our calculations also show a gap in dispersion for very low concentrations of weak links or for very low burning probabilities which indicates a dynamic phase transition between unbiased and biased diffusion regimes. Theoretical findings are supported by Monte Carlo computer simulations.

Experimental and theoretical studies of the thermal behavior of titanium dioxide-SnO2 based composites.

PubMed

Voga, G P; Coelho, M G; de Lima, G M; Belchior, J C

2011-04-07

In this paper we report experimental and theoretical studies concerning the thermal behavior of some organotin-Ti(IV) oxides employed as precursors for TiO(2)/SnO(2) semiconducting based composites, with photocatalytic properties. The organotin-TiO(2) supported materials were obtained by chemical reactions of SnBu(3)Cl (Bu = butyl), TiCl(4) with NH(4)OH in ethanol, in order to impregnate organotin oxide in a TiO(2) matrix. A theoretical model was developed to support experimental procedures. The kinetics parameters: frequency factor (A), activation energy, and reaction order (n) can be estimated through artificial intelligence methods. Genetic algorithm, fuzzy logic, and Petri neural nets were used in order to determine the kinetic parameters as a function of temperature. With this in mind, three precursors were prepared in order to obtain composites with Sn/TiO(2) ratios of 0% (1), 15% (2), and 30% (3) in weight, respectively. The thermal behavior of products (1-3) was studied by thermogravimetric experiments in oxygen.

Linking biodiversity to ecosystem function: Implications for conservation ecology

USGS Publications Warehouse

Schwartz, M.W.; Brigham, C.A.; Hoeksema, J.D.; Lyons, K.G.; Mills, M.H.; van Mantgem, P.

2000-01-01

We evaluate the empirical and theoretical support for the hypothesis that a large proportion of native species richness is required to maximize ecosystem stability and sustain function. This assessment is important for conservation strategies because sustenance of ecosystem functions has been used as an argument for the conservation of species. If ecosystem functions are sustained at relatively low species richness, then arguing for the conservation of ecosystem function, no matter how important in its own right, does not strongly argue for the conservation of species. Additionally, for this to be a strong conservation argument the link between species diversity and ecosystem functions of value to the human community must be clear. We review the empirical literature to quantify the support for two hypotheses: (1) species richness is positively correlated with ecosystem function, and (2) ecosystem functions do not saturate at low species richness relative to the observed or experimental diversity. Few empirical studies demonstrate improved function at high levels of species richness. Second, we analyze recent theoretical models in order to estimate the level of species richness required to maintain ecosystem function. Again we find that, within a single trophic level, most mathematical models predict saturation of ecosystem function at a low proportion of local species richness. We also analyze a theoretical model linking species number to ecosystem stability. This model predicts that species richness beyond the first few species does not typically increase ecosystem stability. One reason that high species richness may not contribute significantly to function or stability is that most communities are characterized by strong dominance such that a few species provide the vast majority of the community biomass. Rapid turnover of species may rescue the concept that diversity leads to maximum function and stability. The role of turnover in ecosystem function and stability has not been investigated. Despite the recent rush to embrace the linkage between biodiversity and ecosystem function, we find little support for the hypothesis that there is a strong dependence of ecosystem function on the full complement of diversity within sites. Given this observation, the conservation community should take a cautious view of endorsing this linkage as a model to promote conservation goals.

Longitudinal train dynamics model for a rail transit simulation system

DOE PAGES

Wang, Jinghui; Rakha, Hesham A.

2018-01-01

The paper develops a longitudinal train dynamics model in support of microscopic railway transportation simulation. The model can be calibrated without any mechanical data making it ideal for implementation in transportation simulators. The calibration and validation work is based on data collected from the Portland light rail train fleet. The calibration procedure is mathematically formulated as a constrained non-linear optimization problem. The validity of the model is assessed by comparing instantaneous model predictions against field observations, and also evaluated in the domains of acceleration/deceleration versus speed and acceleration/deceleration versus distance. A test is conducted to investigate the adequacy of themore » model in simulation implementation. The results demonstrate that the proposed model can adequately capture instantaneous train dynamics, and provides good performance in the simulation test. Thus, the model provides a simple theoretical foundation for microscopic simulators and will significantly support the planning, management and control of railway transportation systems.« less

Longitudinal train dynamics model for a rail transit simulation system

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

Wang, Jinghui; Rakha, Hesham A.

The paper develops a longitudinal train dynamics model in support of microscopic railway transportation simulation. The model can be calibrated without any mechanical data making it ideal for implementation in transportation simulators. The calibration and validation work is based on data collected from the Portland light rail train fleet. The calibration procedure is mathematically formulated as a constrained non-linear optimization problem. The validity of the model is assessed by comparing instantaneous model predictions against field observations, and also evaluated in the domains of acceleration/deceleration versus speed and acceleration/deceleration versus distance. A test is conducted to investigate the adequacy of themore » model in simulation implementation. The results demonstrate that the proposed model can adequately capture instantaneous train dynamics, and provides good performance in the simulation test. Thus, the model provides a simple theoretical foundation for microscopic simulators and will significantly support the planning, management and control of railway transportation systems.« less

Predicting phenolic acid absorption in Caco-2 cells: a theoretical permeability model and mechanistic study.

PubMed

Farrell, Tracy L; Poquet, Laure; Dew, Tristan P; Barber, Stuart; Williamson, Gary

2012-02-01

There is a considerable need to rationalize the membrane permeability and mechanism of transport for potential nutraceuticals. The aim of this investigation was to develop a theoretical permeability equation, based on a reported descriptive absorption model, enabling calculation of the transcellular component of absorption across Caco-2 monolayers. Published data for Caco-2 permeability of 30 drugs transported by the transcellular route were correlated with the descriptors 1-octanol/water distribution coefficient (log D, pH 7.4) and size, based on molecular mass. Nonlinear regression analysis was used to derive a set of model parameters a', β', and b' with an integrated molecular mass function. The new theoretical transcellular permeability (TTP) model obtained a good fit of the published data (R² = 0.93) and predicted reasonably well (R² = 0.86) the experimental apparent permeability coefficient (P(app)) for nine non-training set compounds reportedly transported by the transcellular route. For the first time, the TTP model was used to predict the absorption characteristics of six phenolic acids, and this original investigation was supported by in vitro Caco-2 cell mechanistic studies, which suggested that deviation of the P(app) value from the predicted transcellular permeability (P(app)(trans)) may be attributed to involvement of active uptake, efflux transporters, or paracellular flux.

The role of companionship, esteem, and informational support in explaining physical activity among young women in an online social network intervention.

PubMed

Cavallo, David N; Brown, Jane D; Tate, Deborah F; DeVellis, Robert F; Zimmer, Catherine; Ammerman, Alice S

2014-10-01

The primary objective of the current study was to examine the relationship between social support and physical activity within the theory of planned behavior (TPB) theoretical framework. This study used data from the Internet Support for Healthy Associations Promoting Exercise randomized controlled trial. A total of 134 female undergraduate students participated in the study, which included baseline and post measures of perceived social support for physical activity (esteem, informational, and companionship), TPB variables related to physical activity (perceived behavioral control, intention, and attitude), and physical activity behavior. Path analysis revealed a significant indirect relationship between change in companionship support and physical activity mediated by change in intention (.13, p < .01) and a significant direct relationship between change in esteem support and change in physical activity (.26, p = .03). The model explained 27% of the variance in physical activity and 59% of the variance in intention. Overall, change in social support exerted a small to medium amount of influence on change in physical activity in this modified TPB model when controlling for traditional model constructs. Encouraging companionship and esteem support should be considered as a strategy for increasing physical activity in this population.

Use of qualitative environmental and phenotypic variables in the context of allele distribution models: detecting signatures of selection in the genome of Lake Victoria cichlids.

PubMed

Joost, Stéphane; Kalbermatten, Michael; Bezault, Etienne; Seehausen, Ole

2012-01-01

When searching for loci possibly under selection in the genome, an alternative to population genetics theoretical models is to establish allele distribution models (ADM) for each locus to directly correlate allelic frequencies and environmental variables such as precipitation, temperature, or sun radiation. Such an approach implementing multiple logistic regression models in parallel was implemented within a computing program named MATSAM: . Recently, this application was improved in order to support qualitative environmental predictors as well as to permit the identification of associations between genomic variation and individual phenotypes, allowing the detection of loci involved in the genetic architecture of polymorphic characters. Here, we present the corresponding methodological developments and compare the results produced by software implementing population genetics theoretical models (DFDIST: and BAYESCAN: ) and ADM (MATSAM: ) in an empirical context to detect signatures of genomic divergence associated with speciation in Lake Victoria cichlid fishes.

Optimization of life support systems and their systems reliability

NASA Technical Reports Server (NTRS)

Fan, L. T.; Hwang, C. L.; Erickson, L. E.

1971-01-01

The identification, analysis, and optimization of life support systems and subsystems have been investigated. For each system or subsystem that has been considered, the procedure involves the establishment of a set of system equations (or mathematical model) based on theory and experimental evidences; the analysis and simulation of the model; the optimization of the operation, control, and reliability; analysis of sensitivity of the system based on the model; and, if possible, experimental verification of the theoretical and computational results. Research activities include: (1) modeling of air flow in a confined space; (2) review of several different gas-liquid contactors utilizing centrifugal force: (3) review of carbon dioxide reduction contactors in space vehicles and other enclosed structures: (4) application of modern optimal control theory to environmental control of confined spaces; (5) optimal control of class of nonlinear diffusional distributed parameter systems: (6) optimization of system reliability of life support systems and sub-systems: (7) modeling, simulation and optimal control of the human thermal system: and (8) analysis and optimization of the water-vapor eletrolysis cell.

Theoretical evidence for a first-order liquid-liquid phase transition in gallium.

PubMed

Carvajal Jara, Diego Alejandro; Fontana Michelon, Mateus; Antonelli, Alex; de Koning, Maurice

2009-06-14

We report on theoretical results that lend support to recent experimental observations suggesting the existence of a first-order liquid-liquid phase transformation (LLPT) in gallium. Using molecular dynamics simulation based on a modified embedded-atom model, we observe a transition from a high-density to a low-density liquid in the supercooled regime. The first-order character of the transition is established through the detection of the release of latent heat and our findings suggest that the LLPT terminates in a critical point that is located in the tensile-strained domain of the metastable phase diagram.

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

Sharma, Anupam Deep, E-mail: dr.anupamdeep@yahoo.com; Sinha, M. M.

Perovskite oxides find wide range of applications like oxygen sensors, catalyst support, high frequency capacitors, high temperature superconducting microwave devices, solid state oxide fuel cell (SOFC) etc. LaAlO{sub 3} is one of such type of prominent perovskite oxides and very prominent material for protonic conductions. Therefore knowledge of the thermal properties of LaAlO{sub 3} is most significant. Hence in the present study we have studied phonon density of states and specific heat of LaAlO{sub 3} in cubic structure by applying lattice dynamical theoretical model. The calculated results are interpreted with existing experimental or theoretical results.

THE FERTILITY MOTIVATIONS OF YOUTH PREDICT LATER FERTILITY OUTCOMES: A PROSPECTIVE ANALYSIS OF NLSY DATA*

PubMed Central

Miller, Warren B.; Rodgers, Joseph Lee; Pasta, David J.

2010-01-01

We examine how the motivational sequence that leads to childbearing predicts fertility outcomes across reproductive careers. Using a motivational traits-desires-intentions theoretical framework, we test a structural equation model using prospective male and female data from the National Longitudinal Survey of Youth. Specifically, we take motivational data collected during the 1979–1982 period, when the youths were in their teens and early twenties, to predict the timing of the next child born after 1982 and the total number of children born by 2002. Separate models were estimated for males and females but with equality constraints imposed unless relaxing these constraints improved the overall model fit. The results indicate substantial explanatory power of fertility motivations for both short-term and long-term fertility outcomes. They also reveal the effects of both gender role attitude and educational intentions on these outcomes. Although some sex differences in model pathways occurred, the primary hypothesized pathways were essentially the same across the sexes. Two validity substudies support the soundness of the results. A third substudy comparing the male and female models across the sample split on the basis of previous childbearing revealed a number of pattern differences within the four sex-by-previous childbearing groups. Several of the more robust of these pattern differences offer interesting insights and support the validity and usefulness of our theoretical framework. PMID:20463915

Endogenous fertility, altruistic behavior across generations, and social security systems.

PubMed

Prinz, A

1990-01-01

This study examines the possible link between the existence of a pay-as-you-go social security program and individual procreative behavior. When a public old-age income support system takes the place of within-family support, the theoretical literature preducts that fertility rates will decline since children are no longer perceived as important to the old age security of the parents. The author takes up this theoretical problem and examines it through three different but related issues: optimal capital accumulation, optimal population growth and the role of social institutions affecting efficient intergenerational allocations. Econometric analysis employing a steady state growth model is used. Altruism between generations is studied for effect on the standard model. The model shows that for social optimum the per capita pension is related to the growth rate of the population, therefore, for society as a whole, children are investment goods. However, given the existence of a social security system, it is in each household's best interest to have no children at all. Only a government transfer, a child allowance to parents, changes the model and fertility rates. When modified to account for "caring" the model demonstrates that altruistic behavior between generations is not symmetrical. The study concludes that a pay-as-you-go funded social security system should be supplemented by a system of child allowances or replaced by a fully funded social security system.

MERGING conventional and complementary medicine in a clinic department - a theoretical model and practical recommendations.

PubMed

Pérard, Marion; Mittring, Nadine; Schweiger, David; Kummer, Christopher; Witt, Claudia M

2015-06-09

Today, the increasing demand for complementary medicine encourages health care providers to adapt and create integrative medicine departments or services within clinics. However, because of their differing philosophies, historical development, and settings, merging the partners (conventional and complementary medicine) is often difficult. It is necessary to understand the similarities and differences in both cultures to support a successful and sustainable integration. The aim of this project was to develop a theoretical model and practical steps that are based on theories from mergers in business to facilitate the implementation of an integrative medicine department. Based on a literature search and expert discussions, the cultures were described and model domains were developed. These were applied to two case studies to develop the final model. Furthermore, a checklist with practical steps was devised. Conventional medicine and complementary medicine have developed different corporate cultures. The final model, which should help to foster integration by bridging between these cultures, is based on four overall aspects: culture, strategy, organizational tools and outcomes. Each culture is represented by three dimensions in the model: corporate philosophy (core and identity of the medicine and the clinic), patient (all characteristics of the professional team's contact with the patient), and professional team (the characteristics of the interactions within the professional team). Overall, corporate culture differs between conventional and complementary medicine; when planning the implementation of an integrative medicine department, the developed model and the checklist can support better integration.

Variable-Domain Functional Regression for Modeling ICU Data.

PubMed

Gellar, Jonathan E; Colantuoni, Elizabeth; Needham, Dale M; Crainiceanu, Ciprian M

2014-12-01

We introduce a class of scalar-on-function regression models with subject-specific functional predictor domains. The fundamental idea is to consider a bivariate functional parameter that depends both on the functional argument and on the width of the functional predictor domain. Both parametric and nonparametric models are introduced to fit the functional coefficient. The nonparametric model is theoretically and practically invariant to functional support transformation, or support registration. Methods were motivated by and applied to a study of association between daily measures of the Intensive Care Unit (ICU) Sequential Organ Failure Assessment (SOFA) score and two outcomes: in-hospital mortality, and physical impairment at hospital discharge among survivors. Methods are generally applicable to a large number of new studies that record a continuous variables over unequal domains.

Investigating the cognitive precursors of emotional response to cancer stress: re-testing Lazarus's transactional model.

PubMed

Hulbert-Williams, N J; Morrison, V; Wilkinson, C; Neal, R D

2013-02-01

Lazarus's Transactional Model of stress and coping underwent significant theoretical development through the 1990s to better incorporate emotional reactions to stress with their appraisal components. Few studies have robustly explored the full model. This study aimed to do so within the context of a major life event: cancer diagnosis. A repeated measures design was used whereby data were collected using self-report questionnaire at baseline (soon after diagnosis), and 3- and 6-month follow-up. A total of 160 recently diagnosed cancer patients were recruited (mean time since diagnosis = 46 days). Their mean age was 64.2 years. Data on appraisals, core-relational themes, and emotions were collected. Data were analysed using both Spearman's correlation tests and multivariate regression modelling. Longitudinal analysis demonstrated weak correlation between change scores of theoretically associated components and some emotions correlated more strongly with cognitions contradicting theoretical expectations. Cross-sectional multivariate testing of the ability of cognitions to explain variance in emotion was largely theory inconsistent. Although data support the generic structure of the Transactional Model, they question the model specifics. Larger scale research is needed encompassing a wider range of emotions and using more complex statistical testing. WHAT IS ALREADY KNOWN ON THIS SUBJECT?: • Stress processes are transactional and coping outcome is informed by both cognitive appraisal of the stressor and the individual's emotional response (Lazarus & Folkman, 1984). • Lazarus (1999) made specific hypotheses about which particular stress appraisals would determine which emotional response, but only a small number of these relationships have been robustly investigated. • Previous empirical testing of this theory has been limited by design and statistical limitations. WHAT DOES THIS STUDY ADD?: • This study empirically investigates the cognitive precedents of a much larger range of emotional outcomes than has previously been attempted in the literature. • Support for the model at a general level is established: this study demonstrates that both primary and secondary appraisals, and core-relational themes are important variables in explaining variance in emotional outcome. • The specific hypotheses proposed by Lazarus (1999) are not, however, supported: using data-driven approaches we demonstrate that equally high levels of variance can be explained using entirely different cognitive appraisals than those hypothesized. © 2012 The British Psychological Society.

Reactive Aggression and Posttraumatic Stress in Adolescents Affected by Hurricane Katrina

ERIC Educational Resources Information Center

Marsee, Monica A.

2008-01-01

The current study tests a theoretical model illustrating a potential pathway to reactive aggression through exposure to a traumatic event (Hurricane Katrina) in 166 adolescents (61% female, 63% Caucasian) recruited from high schools on the Gulf Coast of Mississippi. Results support an association between exposure to Hurricane Katrina and reactive…

Acculturation, Enculturation, and Asian American College Students' Mental Health and Attitudes toward Seeking Professional Psychological Help

ERIC Educational Resources Information Center

Miller, Matthew J.; Yang, Minji; Hui, Kayi; Choi, Na-Yeun; Lim, Robert H.

2011-01-01

In the present study, we tested a theoretically and empirically derived partially indirect effects acculturation and enculturation model of Asian American college students' mental health and attitudes toward seeking professional psychological help. Latent variable path analysis with 296 self-identified Asian American college students supported the…

Supporting Evidence-Based Policy on Biodiversity and Ecosystem Services: Recommendations for Effective Policy Briefs

ERIC Educational Resources Information Center

Balian, Estelle V.; Drius, Liza; Eggermont, Hilde; Livoreil, Barbara; Vandewalle, Marie; Vandewoestjine, Sofie; Wittmer, Heidi; Young, Juliette

2016-01-01

Knowledge brokerage on biodiversity and ecosystem services can apply communication tools such as policy briefs to facilitate the dialogue between scientists and policymakers. There is currently considerable debate on how to go beyond the linear communication model, outdated in theoretical debate but still often implicitly leading interaction with…

The Community College IR Shop and Accreditation: A Case Study

ERIC Educational Resources Information Center

Johnston, George

2011-01-01

This article presents results of a study the author recently conducted on the role of traditional institutional research (IR) offices in support of accreditation activities and institutional effectiveness. The purpose of the study was to confirm or disconfirm the utility of a theoretical model developed by Brittingham, O'Brien, and Alig (2008) of…

Student and Teacher Attendance: The Role of Shared Goods in Reducing Absenteeism

ERIC Educational Resources Information Center

Banerjee, Ritwik; King, Elizabeth M.; Orazem, Peter F.; Paterno, Elizabeth M.

2012-01-01

A theoretical model is advanced that demonstrates that, if teacher and student attendance generate a shared good, then teacher and student attendance will be mutually reinforcing. Using data from the Northwest Frontier Province of Pakistan, empirical evidence supporting that proposition is advanced. Controlling for the endogeneity of teacher and…

The Theoretical Basis of Experience-Based Career Education.

ERIC Educational Resources Information Center

Jenks, C. Lynn

This study analyzes the extent to which the assumptions and procedures of the Experience-Based Career Education model (EBCE) as developed by the Far West Laboratory (FWL) are supported by empirical data and by recognized scholars in educational theory. The analysis is presented as relevant to the more general problem: the limited availability of…

Utilizing Educational Theoretical Models to Support Effective Physical Education Pedagogy

ERIC Educational Resources Information Center

Usher, Wayne; Edwards, Allan; de Meyrick, Bianca

2015-01-01

Physical education (PE) pedagogy has traditionally been viewed as drillstyle teaching. Whilst this traditional pedagogical approach provides exposure to various skills, used within a school-based PE and sporting context, it does not demonstrate a student's competence associated with their ability to apply these skills in complex game situations.…

Mental Retardation: Definition, Classification, and Systems of Supports. 10th Edition.

ERIC Educational Resources Information Center

Luckasson, Ruth; Borthwick-Duffy, Sharon; Buntinx, Wil H. E.; Coulter, David L.; Craig, Ellis M.; Reeve, Alya; Schalock, Robert L.; Snell, Martha E.; Spitalnik, Deborah M.; Spreat, Scott; Tasse, Marc J.

This manual, the 10th edition of a regularly published definition and classification work on mental retardation, presents five key assumptions upon which the definition of mental retardation is based and a theoretical model of five essential dimensions that explain mental retardation and how to use the companion system. These dimensions include…

Some Interrelationships between Constructivist Models of Learning and Current Neurobiological Theory, with Implications for Science Education.

ERIC Educational Resources Information Center

Anderson, O. Roger

1992-01-01

This paper examines how some fundamental mechanisms of nervous system activity can explain human information processing and the acquisition of knowledge and provides additional theoretical support for constructivist applications to science education reform. The implications for scientific epistemology and conceptual change processes in science…

Can Proteges Be Successfully Socialized without Socialized Mentors?: A Close Look at Mentorship Formality

ERIC Educational Resources Information Center

Yang, Chun-Chi; Hu, Changya; Baranik, Lisa E.; Lin, Chia-Yu

2013-01-01

Using social cognitive career theory as a theoretical foundation, we examined the relationship between mentor and protege organizational socialization as well as the mediating role of career, psychosocial, and role-modeling support received by proteges. We also examined the moderating role of mentorship formality in the relationship between mentor…

An Analysis of Constructivism and the Ancient Art of Origami

ERIC Educational Resources Information Center

Sze, Susan

2005-01-01

This paper provides a framework for thinking about origami construction and constructivism. In an attempt to understand the conceptual and theoretical framework supporting the field of inclusive teaching strategies in relationship to origami, I have prepared a model for origami which represents six types of constructive learning: (1) Hands-on…

Governance Paradigms of Public Universities: An International Comparative Study

ERIC Educational Resources Information Center

Christopher, Joe

2012-01-01

This study aims to develop a conceptual model of the wider influencing forces impacting the governance paradigms of public universities. It draws on the multi-theoretical governance concept and seeks to identify these forces through the lens of chief audit executives using a qualitative research approach. The interview data supported by published…

A Constructivist Computational Platform to Support Mathematics Education in Elementary School

ERIC Educational Resources Information Center

Garcia, I.; Pacheco, C.

2013-01-01

Many courses for elementary school are based upon teacher presentation and explanation of basic topics, rather than allowing students to develop their own knowledge. This traditional model may turn elementary-level lessons into an extremely theoretical, boring and non-effective process. In this context, research in mathematics elementary education…

The Internet Learning Forum: Developing a Community Prototype for Teachers of the 21st Century.

ERIC Educational Resources Information Center

Reynolds, Eric; Treahy, Diana; Chao, Chin-chi; Barab, Sasha

2001-01-01

Reports on the creation of a community of practice for teachers' professional development via the World Wide Web. Highlights include theoretical foundations; current online models of professional development; and the Internet Learning Forum, a Web site developed to support mathematics and science teachers. (Author/LRW)

Organizational Support and Volunteering Benefits for Older Adults

ERIC Educational Resources Information Center

Tang, Fengyan; Choi, Eunhee; Morrow-Howell, Nancy

2010-01-01

Purpose: This study tested a theoretical model of volunteering benefits and examined the mechanism through which volunteering benefits older adults. Design and Methods: This is a 2-wave study of 253 older adult volunteers serving in 10 volunteer programs. Older volunteers completed the mailed surveys in 2005 and 2006. Structural equation modeling…

Using Online Tools for Communication and Collaboration: Understanding Educators' Experiences in an Online Course

ERIC Educational Resources Information Center

Boling, Erica C.; Holan, Erica; Horbatt, Brent; Hough, Mary; Jean-Louis, Jennifer; Khurana, Chesta; Krinsky, Hindi; Spiezio, Christina

2011-01-01

This designed-based research study explored educators' experiences in an online course to better understand how course design and pedagogical delivery can best support student learning. Using the Cognitive Apprenticeship Model (Collins et al., 1987) as a theoretical lens, researchers investigated the following: 1) What methods of instruction, as…

Transdiagnostic Theory and Application of Family-Based Treatment for Youth with Eating Disorders

ERIC Educational Resources Information Center

Loeb, Katharine L.; Lock, James; Greif, Rebecca; le Grange, Daniel

2012-01-01

This paper describes the transdiagnostic theory and application of family-based treatment (FBT) for children and adolescents with eating disorders. We review the fundamentals of FBT, a transdiagnostic theoretical model of FBT and the literature supporting its clinical application, adaptations across developmental stages and the diagnostic spectrum…

The Effects of Autonomy and Empowerment on Employee Turnover: Test of a Multilevel Model in Teams

ERIC Educational Resources Information Center

Liu, Dong; Zhang, Shu; Wang, Lei; Lee, Thomas W.

2011-01-01

Extending research on voluntary turnover in the team setting, this study adopts a multilevel self-determination theoretical approach to examine the unique roles of individual and social-contextual motivational precursors, autonomy orientation and autonomy support, in reducing team member voluntary turnover. Analysis of multilevel time-lagged data…

Using Reading Times and Eye-Movements to Measure Cognitive Engagement

ERIC Educational Resources Information Center

Miller, Brian W.

2015-01-01

Self-paced reading and eye-tracking can be used to measure microlevel student engagement during science instruction. These methods imply a definition of engagement as the quantity and quality of mental resources directed at an object and the emotions and behaviors entailed. This definition is theoretically supported by models of reading…

Using Generative Routines to Support Learning of Ambitious Mathematics Teaching

ERIC Educational Resources Information Center

Ghousseini, Hala; Beasley, Heather; Lord, Sarah

2017-01-01

In this paper, we integrate a set of theoretical considerations that together serve as a model for investigating how high-leverage practices could be generative of teacher learning. We use the context of rehearsals to investigate how the use of a specified question sequence aimed at eliciting student mathematical thinking can afford opportunities…

Aging and Financial Planning for Retirement: Interdisciplinary Influences Viewed through a Cross-Cultural Lens

ERIC Educational Resources Information Center

Hershey, Douglas A.; Henkens, Kene; van Dalen, Hendrik P.

2010-01-01

Current theoretical models support the existence of interactions between the individual and socio-environmental forces when it comes to the formation and enactment of life plans (Friedman & Scholnick, 1997; Shanahan & Elder, 2002). In this investigation, we examine the social, economic, and psychological forces that impact financial…

Designing a Citizen Involvement Program: A Guidebook for Involving Citizens in the Resolution of Environmental Issues.

ERIC Educational Resources Information Center

Howell, Robert E.; And Others

A model and supportive materials are presented for design and implementation of a program for involving citizens in decision-making concerning significant environmental issues. Chapter topics include: why citizen involvement? (potential benefits of the process); theoretical basis for citizen involvement (three fundamental perspectives underlying…

Lα and Mαβ X-ray production cross-sections of Bi by 6-30 keV electron impact

NASA Astrophysics Data System (ADS)

Liang, Y.; Xu, M. X.; Yuan, Y.; Wu, Y.; Qian, Z. C.; Chang, C. H.; Mei, C. S.; Zhu, J. J.; Moharram, K.

2017-12-01

In this paper, the Lα and Mαβ X-ray production cross-sections for Bi impacted by 6-30 keV electron have been measured. The experiments were performed at a Scanning Electron Microscope equipped with a silicon drift detector. The thin film with thick C substrate and the thin film deposited on self-supporting thin C film were both used as the targets to make a comparison. For the thick carbon substrate target, the Monte Carlo method has been used to eliminate the contribution of backscattering particles. The measured data are compared with the DWBA theoretical model and the experimental results in the literature. The experimental data for the thin film with thick C substrate target and the thin film deposited on self-supporting thin C film target are within reasonable gaps. The DWBA theoretical model gives good fit to the experimental data both for L- and M- shells. Besides, we also analyze the reasons why the discrepancies exist between our measurements and the experimental results in the literature.

Theoretical and experimental studies of the molecular orbital bonding coefficients for Cu{sup 2+} ion in cesium hydrogen oxalate single crystals

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

Kalfaoğlu, Emel, E-mail: emelkalfaoglu@mynet.com; Karabulut, Bünyamin

2016-03-25

Electron paramagnetic resonance (EPR) and optical absorption spectra of Cu{sup 2+} ions in cesium hydrogen oxalate single crystals have been investigated at room temperature. The spin-Hamiltonian parameters (g and A), have been determined. Crystalline field around the Cu{sup 2+} ion is almost axially symmetric. The results show a single paramagnetic site which confirms the triclinic crystal symmetry. Molecular orbital bonding coefficients are studied from the EPR and optical data. Theoretical octahedral field parameter and the tetragonal field parameters have been evaluated from the superposition model. Using these parameters, various bonding parameters are analyzed and the nature of bonding in themore » complex is discussed. The theoretical results are supported by experimental results.« less

Modeling contextual influences on parents with intellectual disability and their children.

PubMed

Wade, Catherine; Llewellyn, Gwynnyth; Matthews, Jan

2011-11-01

Many parents with intellectual disability experience living conditions associated with risk for children and parents. This study used structural equation modeling to test a theoretical model of the relationships among parent, child, family, and contextual variables in 120 Australian families where a parent had an intellectual disability. Findings revealed that parenting practices had a direct effect on children's well being, that social support was associated with children's well being through the mediator of parenting practices, and that access to social support had a direct influence on parenting practices. Implications of the findings for research, intervention, and policy are explored, with the goal of promoting optimal well being for children who are raised by parents with intellectual disability.

Dynamics analysis of the fast-slow hydro-turbine governing system with different time-scale coupling

NASA Astrophysics Data System (ADS)

Zhang, Hao; Chen, Diyi; Wu, Changzhi; Wang, Xiangyu

2018-01-01

Multi-time scales modeling of hydro-turbine governing system is crucial in precise modeling of hydropower plant and provides support for the stability analysis of the system. Considering the inertia and response time of the hydraulic servo system, the hydro-turbine governing system is transformed into the fast-slow hydro-turbine governing system. The effects of the time-scale on the dynamical behavior of the system are analyzed and the fast-slow dynamical behaviors of the system are investigated with different time-scale. Furthermore, the theoretical analysis of the stable regions is presented. The influences of the time-scale on the stable region are analyzed by simulation. The simulation results prove the correctness of the theoretical analysis. More importantly, the methods and results of this paper provide a perspective to multi-time scales modeling of hydro-turbine governing system and contribute to the optimization analysis and control of the system.

Stochastic Simulation of Actin Dynamics Reveals the Role of Annealing and Fragmentation

PubMed Central

Fass, Joseph; Pak, Chi; Bamburg, James; Mogilner, Alex

2008-01-01

Recent observations of F-actin dynamics call for theoretical models to interpret and understand the quantitative data. A number of existing models rely on simplifications and do not take into account F-actin fragmentation and annealing. We use Gillespie’s algorithm for stochastic simulations of the F-actin dynamics including fragmentation and annealing. The simulations vividly illustrate that fragmentation and annealing have little influence on the shape of the polymerization curve and on nucleotide profiles within filaments but drastically affect the F-actin length distribution, making it exponential. We find that recent surprising measurements of high length diffusivity at the critical concentration cannot be explained by fragmentation and annealing events unless both fragmentation rates and frequency of undetected fragmentation and annealing events are greater than previously thought. The simulations compare well with experimentally measured actin polymerization data and lend additional support to a number of existing theoretical models. PMID:18279896

Towards a multi-level approach to the emergence of meaning processes in living systems.

PubMed

Queiroz, João; El-Hani, Charbel Niño

2006-09-01

Any description of the emergence and evolution of different types of meaning processes (semiosis, sensu C.S.Peirce) in living systems must be supported by a theoretical framework which makes it possible to understand the nature and dynamics of such processes. Here we propose that the emergence of semiosis of different kinds can be understood as resulting from fundamental interactions in a triadically-organized hierarchical process. To grasp these interactions, we develop a model grounded on Stanley Salthe's hierarchical structuralism. This model can be applied to establish, in a general sense, a set of theoretical constraints for explaining the instantiation of different kinds of meaning processes (iconic, indexical, symbolic) in semiotic systems. We use it to model a semiotic process in the immune system, namely, B-cell activation, in order to offer insights into the heuristic role it can play in the development of explanations for specific semiotic processes.

Modeling of SBS Phase Conjugation in Multimode Step Index Fibers

DTIC Science & Technology

2008-03-01

cavity or in an external amplifier. Since pumping is never a perfectly efficient process, some heat will be introduced, and for very high pump powers...modes it supports, and the incident pump power. While theoretical investigations of SBS PCMs have been conducted by a num- ber of authors, the model...predictions about the phase conjugate fidelity that could be expected from a given pump intensity input coupled into a specific fiber. A numerical

A Relational Encoding of a Conceptual Model with Multiple Temporal Dimensions

NASA Astrophysics Data System (ADS)

Gubiani, Donatella; Montanari, Angelo

The theoretical interest and the practical relevance of a systematic treatment of multiple temporal dimensions is widely recognized in the database and information system communities. Nevertheless, most relational databases have no temporal support at all. A few of them provide a limited support, in terms of temporal data types and predicates, constructors, and functions for the management of time values (borrowed from the SQL standard). One (resp., two) temporal dimensions are supported by historical and transaction-time (resp., bitemporal) databases only. In this paper, we provide a relational encoding of a conceptual model featuring four temporal dimensions, namely, the classical valid and transaction times, plus the event and availability times. We focus our attention on the distinctive technical features of the proposed temporal extension of the relation model. In the last part of the paper, we briefly show how to implement it in a standard DBMS.

Effect of differentiation of self on adolescent risk behavior: test of the theoretical model.

PubMed

Knauth, Donna G; Skowron, Elizabeth A; Escobar, Melicia

2006-01-01

Innovative theoretical models are needed to explain the occurrence of high-risk sexual behaviors, alcohol and other-drug (AOD) use, and academic engagement among ethnically diverse, inner-city adolescents. The aim of this study was to test the credibility of a theoretical model based on the Bowen family systems theory to explain adolescent risk behavior. Specifically tested was the relationship between the predictor variables of differentiation of self, chronic anxiety, and social problem solving and the dependent variables of high-risk sexual behaviors, AOD use, and academic engagement. An ex post facto cross-sectional design was used to test the usefulness of the theoretical model. Data were collected from 161 racially/ethnically diverse, inner-city high school students, 14 to 19 years of age. Participants completed self-report written questionnaires, including the Differentiation of Self Inventory, State-Trait Anxiety Inventory, Social Problem Solving for Adolescents, Drug Involvement Scale for Adolescents, and the Sexual Behavior Questionnaire. Consistent with the model, higher levels of differentiation of self related to lower levels of chronic anxiety (p < .001) and higher levels of social problem solving (p < .01). Higher chronic anxiety was related to lower social problem solving (p < .001). A test of mediation showed that chronic anxiety mediates the relationship between differentiation of self and social problem solving (p < .001), indicating that differentiation influences social problem solving through chronic anxiety. Higher levels of social problem solving were related to less drug use (p < .05), less high-risk sexual behaviors (p < .01), and an increase in academic engagement (p < .01). Findings support the theoretical model's credibility and provide evidence that differentiation of self is an important cognitive factor that enables adolescents to manage chronic anxiety and motivates them to use effective problem solving, resulting in less involvement in health-comprising behaviors and increased academic engagement.

Action Centered Contextual Bandits.

PubMed

Greenewald, Kristjan; Tewari, Ambuj; Klasnja, Predrag; Murphy, Susan

2017-12-01

Contextual bandits have become popular as they offer a middle ground between very simple approaches based on multi-armed bandits and very complex approaches using the full power of reinforcement learning. They have demonstrated success in web applications and have a rich body of associated theoretical guarantees. Linear models are well understood theoretically and preferred by practitioners because they are not only easily interpretable but also simple to implement and debug. Furthermore, if the linear model is true, we get very strong performance guarantees. Unfortunately, in emerging applications in mobile health, the time-invariant linear model assumption is untenable. We provide an extension of the linear model for contextual bandits that has two parts: baseline reward and treatment effect. We allow the former to be complex but keep the latter simple. We argue that this model is plausible for mobile health applications. At the same time, it leads to algorithms with strong performance guarantees as in the linear model setting, while still allowing for complex nonlinear baseline modeling. Our theory is supported by experiments on data gathered in a recently concluded mobile health study.

Anxiety: towards a decision-theoretic perspective.

PubMed

Shechter, M; Zeidner, M

1990-05-01

This paper sets out to illustrate how anxiety may be incorporated into a formal decision theoretic utility model of choice, and to suggest several measurement procedures towards that end. The major propositions derived and posited in this paper lend considerable support to intuitive notions with respect to the effects of anxiety on human behaviour in risky decision situations. Namely, that the willingness of an individual to pay to reduce health risks (an economic indicator of individual welfare associated with reduced morbidity or increased longevity) tends to be positive and higher when anxiety is present than when it is not. The formal results of the analysis show that when psychological considerations are incorporated into a state-dependent utility model, the normative results customarily obtained concerning value-of-life need to be qualified.

Testing an integrated behavioural and biomedical model of disability in N-of-1 studies with chronic pain.

PubMed

Quinn, Francis; Johnston, Marie; Johnston, Derek W

2013-01-01

Previous research has supported an integrated biomedical and behavioural model explaining activity limitations. However, further tests of this model are required at the within-person level, because while it proposes that the constructs are related within individuals, it has primarily been tested between individuals in large group studies. We aimed to test the integrated model at the within-person level. Six correlational N-of-1 studies in participants with arthritis, chronic pain and walking limitations were carried out. Daily measures of theoretical constructs were collected using a hand-held computer (PDA), the activity was assessed by self-report and accelerometer and the data were analysed using time-series analysis. The biomedical model was not supported as pain impairment did not predict activity, so the integrated model was supported partially. Impairment predicted intention to move around, while perceived behavioural control (PBC) and intention predicted activity. PBC did not predict activity limitation in the expected direction. The integrated model of disability was partially supported within individuals, especially the behavioural elements. However, results suggest that different elements of the model may drive activity (limitations) for different individuals. The integrated model provides a useful framework for understanding disability and suggests interventions, and the utility of N-of-1 methodology for testing theory is illustrated.

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

Streets, W.E.

As the need for rapid and more accurate determinations of gamma-emitting radionuclides in environmental and mixed waste samples grows, there is continued interest in the development of theoretical tools to eliminate the need for some laboratory analyses and to enhance the quality of information from necessary analyses. In gamma spectrometry the use of theoretical self-absorption coefficients (SACs) can eliminate the need to determine the SAC empirically by counting a known source through each sample. This empirical approach requires extra counting time and introduces another source of counting error, which must be included in the calculation of results. The empirical determinationmore » of SACs is routinely used when the nuclides of interest are specified; theoretical determination of the SAC can enhance the information for the analysis of true unknowns, where there may be no prior knowledge about radionuclides present in a sample. Determination of an exact SAC does require knowledge about the total composition of a sample. In support of the Department of Energy`s (DOE) Environmental Survey Program, the Analytical Chemistry Laboratory (ACL) at Argonne National Laboratory developed theoretical self-absorption models to estimate SACs for the determination of non-specified radionuclides in samples of unknown, widely-varying, compositions. Subsequently, another SAC model, in a different counting geometry and for specified nuclides, was developed for another application. These two models are now used routinely for the determination of gamma-emitting radionuclides in a wide variety of environmental and mixed waste samples.« less

Implicit emotion regulation in adolescent girls: An exploratory investigation of Hidden Markov Modeling and its neural correlates.

PubMed

Steele, James S; Bush, Keith; Stowe, Zachary N; James, George A; Smitherman, Sonet; Kilts, Clint D; Cisler, Josh

2018-01-01

Numerous data demonstrate that distracting emotional stimuli cause behavioral slowing (i.e. emotional conflict) and that behavior dynamically adapts to such distractors. However, the cognitive and neural mechanisms that mediate these behavioral findings are poorly understood. Several theoretical models have been developed that attempt to explain these phenomena, but these models have not been directly tested on human behavior nor compared. A potential tool to overcome this limitation is Hidden Markov Modeling (HMM), which is a computational approach to modeling indirectly observed systems. Here, we administered an emotional Stroop task to a sample of healthy adolescent girls (N = 24) during fMRI and used HMM to implement theoretical behavioral models. We then compared the model fits and tested for neural representations of the hidden states of the most supported model. We found that a modified variant of the model posited by Mathews et al. (1998) was most concordant with observed behavior and that brain activity was related to the model-based hidden states. Particularly, while the valences of the stimuli themselves were encoded primarily in the ventral visual cortex, the model-based detection of threatening targets was associated with increased activity in the bilateral anterior insula, while task effort (i.e. adaptation) was associated with reduction in the activity of these areas. These findings suggest that emotional target detection and adaptation are accomplished partly through increases and decreases, respectively, in the perceived immediate relevance of threatening cues and also demonstrate the efficacy of using HMM to apply theoretical models to human behavior.

Implicit emotion regulation in adolescent girls: An exploratory investigation of Hidden Markov Modeling and its neural correlates

PubMed Central

Bush, Keith; Stowe, Zachary N.; James, George A.; Smitherman, Sonet; Kilts, Clint D.; Cisler, Josh

2018-01-01

Numerous data demonstrate that distracting emotional stimuli cause behavioral slowing (i.e. emotional conflict) and that behavior dynamically adapts to such distractors. However, the cognitive and neural mechanisms that mediate these behavioral findings are poorly understood. Several theoretical models have been developed that attempt to explain these phenomena, but these models have not been directly tested on human behavior nor compared. A potential tool to overcome this limitation is Hidden Markov Modeling (HMM), which is a computational approach to modeling indirectly observed systems. Here, we administered an emotional Stroop task to a sample of healthy adolescent girls (N = 24) during fMRI and used HMM to implement theoretical behavioral models. We then compared the model fits and tested for neural representations of the hidden states of the most supported model. We found that a modified variant of the model posited by Mathews et al. (1998) was most concordant with observed behavior and that brain activity was related to the model-based hidden states. Particularly, while the valences of the stimuli themselves were encoded primarily in the ventral visual cortex, the model-based detection of threatening targets was associated with increased activity in the bilateral anterior insula, while task effort (i.e. adaptation) was associated with reduction in the activity of these areas. These findings suggest that emotional target detection and adaptation are accomplished partly through increases and decreases, respectively, in the perceived immediate relevance of threatening cues and also demonstrate the efficacy of using HMM to apply theoretical models to human behavior. PMID:29489856

The consciousness state space (CSS)—a unifying model for consciousness and self

PubMed Central

Berkovich-Ohana, Aviva; Glicksohn, Joseph

2014-01-01

Every experience, those we are aware of and those we are not, is embedded in a subjective timeline, is tinged with emotion, and inevitably evokes a certain sense of self. Here, we present a phenomenological model for consciousness and selfhood which relates time, awareness, and emotion within one framework. The consciousness state space (CSS) model is a theoretical one. It relies on a broad range of literature, hence has high explanatory and integrative strength, and helps in visualizing the relationship between different aspects of experience. Briefly, it is suggested that all phenomenological states fall into two categories of consciousness, core and extended (CC and EC, respectively). CC supports minimal selfhood that is short of temporal extension, its scope being the here and now. EC supports narrative selfhood, which involves personal identity and continuity across time, as well as memory, imagination and conceptual thought. The CSS is a phenomenological space, created by three dimensions: time, awareness and emotion. Each of the three dimensions is shown to have a dual phenomenological composition, falling within CC and EC. The neural spaces supporting each of these dimensions, as well as CC and EC, are laid out based on the neuroscientific literature. The CSS dynamics include two simultaneous trajectories, one in CC and one in EC, typically antagonistic in normal experiences. However, this characteristic behavior is altered in states in which a person experiences an altered sense of self. Two examples are laid out, flow and meditation. The CSS model creates a broad theoretical framework with explanatory and unificatory power. It constructs a detailed map of the consciousness and selfhood phenomenology, which offers constraints for the science of consciousness. We conclude by outlining several testable predictions raised by the CSS model. PMID:24808870

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

NASA Astrophysics Data System (ADS)

Lamersdorf, Ansgar; Münch, Jürgen; Rombach, Dieter

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

The influence of authentic leadership and empowerment on nurses' relational social capital, mental health and job satisfaction over the first year of practice.

PubMed

Read, Emily A; Laschinger, Heather K S

2015-07-01

To examine a theoretical model testing the effects of authentic leadership, structural empowerment and relational social capital on the mental health and job satisfaction of new graduate nurses over the first year of practice. Relational social capital is an important interpersonal organizational resource that may foster new graduate nurses' workplace well-being and promote retention. Evidence shows that authentic leadership and structural empowerment are key aspects of the work environment that support new graduate nurses; however, the mediating role of relational social capital has yet to be explored. A longitudinal survey design was used to test the hypothesized model. One hundred ninety-one new graduate nurses in Ontario with <2 years of experience completed mail surveys in January-March 2010 and 1 year later in 2011. Path analysis using structural equation modelling was used to test the theoretical model. Participants were mostly female, working full time in medicine/surgery or critical care. All measures demonstrated acceptable reliability and validity. Path analysis results supported our hypothesized model; structural empowerment mediated the relationship between authentic leadership and nurses' relational social capital, which in turn had a negative effect on mental health symptoms and a positive effect on job satisfaction. All indirect paths in the model were significant. By creating structurally empowering work environments, authentic leaders foster relational social capital among new graduate nurses leading to positive health and retention outcomes. © 2015 John Wiley & Sons Ltd.

Final Report of DOE Grant No. DE-FG02-04ER41306

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

Nandi, Satyanarayan; Babu, Kaladi S; Rizatdinova, Flera

2013-12-10

Project: Theoretical and Experimental Research in Weak, Electromagnetic and Strong Interactions: Investigators: S. Nandi, K.S. Babu, F. Rizatdinova Institution: Oklahoma State University, Stillwater, OK 74078 This completed project focused on the cutting edge research in theoretical and experimental high energy physics. In theoretical high energy physics, the two investigators (Nandi and Babu) worked on a variety of topics in model-building and phenomenological aspects of elementary particle physics. This includes unification of particles and forces, neutrino physics, Higgs boson physics, proton decay, supersymmetry, and collider physics. Novel physics ideas beyond the Standard Model with testable consequences at the LHC have beenmore » proposed. These ideas have stimulated the experimental community to look for new signals. The contributions of the experimental high energy physics group has been at the D0 experiment at the Fermilab Tevatraon and the ATLAS experiment at the Large Hadron Collider. At the D0 experiment, the main focus was search for the Higgs boson in the WH channel, where improved limits were obtained. At the LHC, the OSU group has made significant contributions to the top quark physics, and the calibration of the b-tagging algorithms. The group is also involved in the pixel detector upgrade. This DOE supported grant has resulted in 5 PhD degrees during the past three years. Three postdoctoral fellows were supported as well. In theoretical research over 40 refereed publications have resulted in the past three years, with several involving graduate students and postdoctoral fellows. It also resulted in over 30 conference presentations in the same time period. We are also involved in outreach activities through the Quarknet program, where we engage Oklahoma school teachers and students in our research.« less

Experimental and theoretical investigation of the first-order hyperpolarizability of a class of triarylamine derivatives

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

Silva, Daniel L., E-mail: dlsilva.physics@gmail.com, E-mail: deboni@ifsc.usp.br; Instituto de Física, Universidade de São Paulo, CP 66318, 05314-970 São Paulo, SP; Fonseca, Ruben D.

2015-02-14

This paper reports on the static and dynamic first-order hyperpolarizabilities of a class of push-pull octupolar triarylamine derivatives dissolved in toluene. We have combined hyper-Rayleigh scattering experiment and the coupled perturbed Hartree-Fock method implemented at the Density Functional Theory (DFT) level of theory to determine the static and dynamic (at 1064 nm) first-order hyperpolarizability (β{sub HRS}) of nine triarylamine derivatives with distinct electron-withdrawing groups. In four of these derivatives, an azoaromatic unit is inserted and a pronounceable increase of the first-order hyperpolarizability is reported. Based on the theoretical results, the dipolar/octupolar character of the derivatives is determined. By using amore » polarizable continuum model in combination with the DFT calculations, it was found that although solvated in an aprotic and low dielectric constant solvent, due to solvent-induced polarization and the frequency dispersion effect, the environment substantially affects the first-order hyperpolarizability of all derivatives investigated. This statement is supported due to the solvent effects to be essential for the better agreement between theoretical results and experimental data concerning the dynamic first-order hyperpolarizability of the derivatives. The first-order hyperpolarizability of the derivatives was also modeled using the two- and three-level models, where the relationship between static and dynamic first hyperpolarizabilities is given by a frequency dispersion model. Using this approach, it was verified that the dynamic first hyperpolarizability of the derivatives is satisfactorily reproduced by the two-level model and that, in the case of the derivatives with an azoaromatic unit, the use of a damped few-level model is essential for, considering also the molecular size of such derivatives, a good quantitative agreement between theoretical results and experimental data to be observed.« less

Analysis of collapse in flattening a micro-grooved heat pipe by lateral compression

NASA Astrophysics Data System (ADS)

Li, Yong; He, Ting; Zeng, Zhixin

2012-11-01

The collapse of thin-walled micro-grooved heat pipes is a common phenomenon in the tube flattening process, which seriously influences the heat transfer performance and appearance of heat pipe. At present, there is no other better method to solve this problem. A new method by heating the heat pipe is proposed to eliminate the collapse during the flattening process. The effectiveness of the proposed method is investigated through a theoretical model, a finite element(FE) analysis, and experimental method. Firstly, A theoretical model based on a deformation model of six plastic hinges and the Antoine equation of the working fluid is established to analyze the collapse of thin walls at different temperatures. Then, the FE simulation and experiments of flattening process at different temperatures are carried out and compared with theoretical model. Finally, the FE model is followed to study the loads of the plates at different temperatures and heights of flattened heat pipes. The results of the theoretical model conform to those of the FE simulation and experiments in the flattened zone. The collapse occurs at room temperature. As the temperature increases, the collapse decreases and finally disappears at approximately 130 °C for various heights of flattened heat pipes. The loads of the moving plate increase as the temperature increases. Thus, the reasonable temperature for eliminating the collapse and reducing the load is approximately 130 °C. The advantage of the proposed method is that the collapse is reduced or eliminated by means of the thermal deformation characteristic of heat pipe itself instead of by external support. As a result, the heat transfer efficiency of heat pipe is raised.

Can Economics Provide Insights into Trust Infrastructure?

NASA Astrophysics Data System (ADS)

Vishik, Claire

Many security technologies require infrastructure for authentication, verification, and other processes. In many cases, viable and innovative security technologies are never adopted on a large scale because the necessary infrastructure is slow to emerge. Analyses of such technologies typically focus on their technical flaws, and research emphasizes innovative approaches to stronger implementation of the core features. However, an observation can be made that in many cases the success of adoption pattern depends on non-technical issues rather than technology-lack of economic incentives, difficulties in finding initial investment, inadequate government support. While a growing body of research is dedicated to economics of security and privacy in general, few theoretical studies in this area have been completed, and even fewer that look at the economics of “trust infrastructure” beyond simple “cost of ownership” models. This exploratory paper takes a look at some approaches in theoretical economics to determine if they can provide useful insights into security infrastructure technologies and architectures that have the best chance to be adopted. We attempt to discover if models used in theoretical economics can help inform technology developers of the optimal business models that offer a better chance for quick infrastructure deployment.

Recent theoretical, neural, and clinical advances in sustained attention research

PubMed Central

Fortenbaugh, Francesca C.; DeGutis, Joseph; Esterman, Michael

2017-01-01

Models of attention often distinguish between attention subtypes, with classic models separating orienting, switching, and sustaining functions. Compared to other forms of attention, the neurophysiological basis of sustaining attention has received far less attention yet it is known that momentary failures of sustained attention can have far ranging negative impacts in healthy individuals and lasting sustained attention deficits are pervasive in clinical populations. In recent years, however, there has been increased interest in characterizing moment-to-moment fluctuations in sustained attention in addition to the overall vigilance decrement and understanding how these neurocognitive systems change over the lifespan and across various clinical populations. The use of novel neuroimaging paradigms and statistical approaches has allowed for better characterization of the neural networks supporting sustained attention, and highlighted dynamic interactions within and across multiple distributed networks that predict behavioral performance. These advances have also provided potential biomarkers to identify individuals with sustained attention deficits. These findings have led to new theoretical models of why sustaining focused attention is a challenge for individuals and form the basis for the next generation of sustained attention research, which seeks to accurately diagnose and develop theoretically-driven treatments for sustained attention deficits that affect a variety of clinical populations. PMID:28260249

The Bereavement Guilt Scale.

PubMed

Li, Jie; Stroebe, Magaret; Chan, Cecilia L W; Chow, Amy Y M

2017-06-01

The rationale, development, and validation of the Bereavement Guilt Scale (BGS) are described in this article. The BGS was based on a theoretically developed, multidimensional conceptualization of guilt. Part 1 describes the generation of the item pool, derived from in-depth interviews, and review of the scientific literature. Part 2 details statistical analyses for further item selection (Sample 1, N = 273). Part 3 covers the psychometric properties of the emergent-BGS (Sample 2, N = 600, and Sample 3, N = 479). Confirmatory factor analysis indicated that a five-factor model fit the data best. Correlations of BGS scores with depression, anxiety, self-esteem, self-forgiveness, and mode of death were consistent with theoretical predictions, supporting the construct validity of the measure. The internal consistency and test-retest reliability were also supported. Thus, initial testing or examination suggests that the BGS is a valid tool to assess multiple components of bereavement guilt. Further psychometric testing across cultures is recommended.

A Game Theoretic Optimization Method for Energy Efficient Global Connectivity in Hybrid Wireless Sensor Networks

PubMed Central

Lee, JongHyup; Pak, Dohyun

2016-01-01

For practical deployment of wireless sensor networks (WSN), WSNs construct clusters, where a sensor node communicates with other nodes in its cluster, and a cluster head support connectivity between the sensor nodes and a sink node. In hybrid WSNs, cluster heads have cellular network interfaces for global connectivity. However, when WSNs are active and the load of cellular networks is high, the optimal assignment of cluster heads to base stations becomes critical. Therefore, in this paper, we propose a game theoretic model to find the optimal assignment of base stations for hybrid WSNs. Since the communication and energy cost is different according to cellular systems, we devise two game models for TDMA/FDMA and CDMA systems employing power prices to adapt to the varying efficiency of recent wireless technologies. The proposed model is defined on the assumptions of the ideal sensing field, but our evaluation shows that the proposed model is more adaptive and energy efficient than local selections. PMID:27589743

[Validity evidence of the Health-Related Quality of Life for Drug Abusers Test based on the Biaxial Model of Addiction].

PubMed

Lozano, Oscar M; Rojas, Antonio J; Pérez, Cristino; González-Sáiz, Francisco; Ballesta, Rosario; Izaskun, Bilbao

2008-05-01

The aim of this work is to show evidence of the validity of the Health-Related Quality of Life for Drug Abusers Test (HRQoLDA Test). This test was developed to measure specific HRQoL for drugs abusers, within the theoretical addiction framework of the biaxial model. The sample comprised 138 patients diagnosed with opiate drug dependence. In this study, the following constructs and variables of the biaxial model were measured: severity of dependence, physical health status, psychological adjustment and substance consumption. Results indicate that the HRQoLDA Test scores are related to dependency and consumption-related problems. Multiple regression analysis reveals that HRQoL can be predicted from drug dependence, physical health status and psychological adjustment. These results contribute empirical evidence of the theoretical relationships established between HRQoL and the biaxial model, and they support the interpretation of the HRQoLDA Test to measure HRQoL in drug abusers, thus providing a test to measure this specific construct in this population.

ICT & OTs: a model of information and communications technology acceptance and utilisation by occupational therapists (part 2).

PubMed

Schaper, Louise; Pervan, Graham

2007-01-01

The research reported in this paper describes the development, empirical validation and analysis of a model of technology acceptance by Australian occupational therapists. The study described involved the collection of quantitative data through a national survey. The theoretical significance of this work is that it uses a thoroughly constructed research model, with one of the largest sample sizes ever tested (n=1605), to extend technology acceptance research into the health sector. Results provide strong support for the model. This work reveals the complexity of the constructs and relationships that influence technology acceptance and highlights the need to include sociotechnical and system issues in studies of technology acceptance in healthcare to improve information system implementation success in this arena. The results of this study have practical and theoretical implications for health informaticians and researchers in the field of health informatics and information systems, tertiary educators, Commonwealth and State Governments and the allied health professions.

The quantitative modelling of human spatial habitability

NASA Technical Reports Server (NTRS)

Wise, James A.

1988-01-01

A theoretical model for evaluating human spatial habitability (HuSH) in the proposed U.S. Space Station is developed. Optimizing the fitness of the space station environment for human occupancy will help reduce environmental stress due to long-term isolation and confinement in its small habitable volume. The development of tools that operationalize the behavioral bases of spatial volume for visual kinesthetic, and social logic considerations is suggested. This report further calls for systematic scientific investigations of how much real and how much perceived volume people need in order to function normally and with minimal stress in space-based settings. The theoretical model presented in this report can be applied to any size or shape interior, at any scale of consideration, for the Space Station as a whole to an individual enclosure or work station. Using as a point of departure the Isovist model developed by Dr. Michael Benedikt of the U. of Texas, the report suggests that spatial habitability can become as amenable to careful assessment as engineering and life support concerns.

Emotional Exhaustion and Job Satisfaction in Airport Security Officers - Work-Family Conflict as Mediator in the Job Demands-Resources Model.

PubMed

Baeriswyl, Sophie; Krause, Andreas; Schwaninger, Adrian

2016-01-01

The growing threat of terrorism has increased the importance of aviation security and the work of airport security officers (screeners). Nonetheless, airport security research has yet to focus on emotional exhaustion and job satisfaction as major determinants of screeners' job performance. The present study bridges this research gap by applying the job demands-resources (JD-R) model and using work-family conflict (WFC) as an intervening variable to study relationships between work characteristics (workload and supervisor support), emotional exhaustion, and job satisfaction in 1,127 screeners at a European airport. Results of structural equation modeling revealed that (a) supervisor support as a major job resource predicted job satisfaction among screeners; (b) workload as a major job demand predicted their emotional exhaustion; and (c) WFC proved to be a promising extension to the JD-R model that partially mediated the impact of supervisor support and workload on job satisfaction and emotional exhaustion. Theoretical and practical implications are discussed.

Emotional Exhaustion and Job Satisfaction in Airport Security Officers – Work–Family Conflict as Mediator in the Job Demands–Resources Model

PubMed Central

Baeriswyl, Sophie; Krause, Andreas; Schwaninger, Adrian

2016-01-01

The growing threat of terrorism has increased the importance of aviation security and the work of airport security officers (screeners). Nonetheless, airport security research has yet to focus on emotional exhaustion and job satisfaction as major determinants of screeners’ job performance. The present study bridges this research gap by applying the job demands–resources (JD–R) model and using work–family conflict (WFC) as an intervening variable to study relationships between work characteristics (workload and supervisor support), emotional exhaustion, and job satisfaction in 1,127 screeners at a European airport. Results of structural equation modeling revealed that (a) supervisor support as a major job resource predicted job satisfaction among screeners; (b) workload as a major job demand predicted their emotional exhaustion; and (c) WFC proved to be a promising extension to the JD–R model that partially mediated the impact of supervisor support and workload on job satisfaction and emotional exhaustion. Theoretical and practical implications are discussed. PMID:27242581

Dynamic modeling and experiments on the coupled vibrations of building and elevator ropes

NASA Astrophysics Data System (ADS)

Yang, Dong-Ho; Kim, Ki-Young; Kwak, Moon K.; Lee, Seungjun

2017-03-01

This study is concerned with the theoretical modelling and experimental verification of the coupled vibrations of building and elevator ropes. The elevator ropes consist of a main rope which supports the cage and the compensation rope which is connected to the compensation sheave. The elevator rope is a flexible wire with a low damping, so it is prone to vibrations. In the case of a high-rise building, the rope length also increases significantly, so that the fundamental frequency of the elevator rope approaches the fundamental frequency of the building thus increasing the possibility of resonance. In this study, the dynamic model for the analysis of coupled vibrations of building and elevator ropes was derived by using Hamilton's principle, where the cage motion was also considered. An experimental testbed was built to validate the proposed dynamic model. It was found that the experimental results are in good agreement with the theoretical predictions thus validating the proposed dynamic model. The proposed model was then used to predict the vibrations of real building and elevator ropes.

The need for international nursing diagnosis research and a theoretical framework.

PubMed

Lunney, Margaret

2008-01-01

To describe the need for nursing diagnosis research and a theoretical framework for such research. A linguistics theory served as the foundation for the theoretical framework. Reasons for additional nursing diagnosis research are: (a) file names are needed for implementation of electronic health records, (b) international consensus is needed for an international classification, and (c) continuous changes occur in clinical practice. A theoretical framework used by the author is explained. Theoretical frameworks provide support for nursing diagnosis research. Linguistics theory served as an appropriate exemplar theory to support nursing research. Additional nursing diagnosis studies based upon a theoretical framework are needed and linguistics theory can provide an appropriate structure for this research.

The Development of Fire Support Coordination for Amphibious Operations between World Wars I and II

DTIC Science & Technology

1987-06-05

Thus I do not Intend to substitute " Invest -gative norms" or theoretical "research models" for basic research and deductive reasoning. Since the...Noble also stated that the doctrine which was prepared was fundemental and only I prescribed that something be accomplished. This meant that all

Project-Based Learning and Pedagogy in Teacher Preparation: Staking out the Theoretical Mid-Ground

ERIC Educational Resources Information Center

Roessingh, Hetty; Chambers, Wendy

2011-01-01

In this article, we advance a model of project-based learning (PJBL) offering eight guiding principles to support a pragmatic and principled approach to teacher preparation at the undergraduate and graduate levels. We provide a template for structuring PJBL, and we include illustrative exemplars that demonstrate that the ideological mid-ground can…

Study of solid rocket motor for a space shuttle booster. Appendix A: SRM water entry loads

NASA Technical Reports Server (NTRS)

1972-01-01

An analysis of the water entry loads imposed on the reusable solid propellant rocket engine of the space shuttle following parachute descent is presented. The cases discussed are vertical motion, horizontal motion, and motion after penetration. Mathematical models, diagrams, and charts are included to support the theoretical considerations.

Why Increased Social Presence through Web Videoconferencing Does Not Automatically Lead to Improved Learning

ERIC Educational Resources Information Center

Giesbers, Bas; Rienties, Bart; Tempelaar, Dirk T.; Gijselaers, Wim

2014-01-01

The Community of Inquiry (CoI) model provides a well-researched theoretical framework to understand how learners and teachers interact and learn together in computer-supported collaborative learning (CSCL). Most CoI research focuses on asynchronous learning. However, with the arrival of easy-to-use synchronous communication tools the relevance of…

New Experimental Approaches and Theoretical Modeling Methods for Laser Cooling Atoms and Molecules

DTIC Science & Technology

2006-07-27

support of experimental efforts in various laboratories to produce ultracold molecules by laser -induced photoassociation of laser -cooled atoms. We are......temperatures so far have been 25mK [7], rather than tens of µK as one can achieve with laser cooling of atoms. Thus an approach that begins with cold

Critical Argument and Writer Identity: Social Constructivism as a Theoretical Framework for EFL Academic Writing

ERIC Educational Resources Information Center

McKinley, Jim

2015-01-01

This article makes the argument that we need to situate student's academic writing as socially constructed pieces of writing that embody a writer's cultural identity and critical argument. In support, I present and describe a comprehensive model of an original English as a Foreign Language (EFL) writing analytical framework. This article explains…

Toward an Interdisciplinary Perspective: A Review of Adult Learning Frameworks and Theoretical Models of Motor Learning

ERIC Educational Resources Information Center

Roessger, Kevin M.

2012-01-01

Researchers have yet to agree on an approach that supports how adults best learn novel motor skills in formal educational contexts. The literature fails to adequately discuss adult motor learning from the standpoint of adult education. Instead, the subject is addressed by other disciplines. This review attempts to integrate perspectives across…

A Probe into the Internationalisation of Higher Education in the New Zealand Context

ERIC Educational Resources Information Center

Jiang, Xiaoping

2010-01-01

This paper presents a model of practice for analysing the internationalisation of higher education, and for better providing teaching service and support to both the internal and external other. It is derived from the theoretical analysis of the rationales, concepts and developments of the internationalisation of higher education, and from a New…

Entrainment regimes and flame characteristics of wildland fires

Treesearch

Ralph M. Nelson; Bret W. Butler; David R. Weise

2012-01-01

This paper reports results from a study of the flame characteristics of 22 wind-aided pine litter fires in a laboratory wind tunnel and 32 field fires in southern rough and litter-grass fuels. Flame characteristic and fire behaviour data from these fires, simple theoretical flame models and regression techniques are used to determine whether the data support the...

Perceived Discrimination and Psychological Distress: The Role of Personal and Ethnic Self-Esteem

ERIC Educational Resources Information Center

Cassidy, Clare; O'Connor, Rory C.; Howe, Christine; Warden, David

2004-01-01

The present study aimed to draw on 2 theoretical models to examine the relationship between perceived ethnic discrimination and psychological distress in a sample of ethnic minority young people (N=154). Analysis provided no support for the hypothesis derived from the self-esteem theory of depression that self-esteem (personal and ethnic)…

Role Resources and Work-Family Enrichment: The Role of Work Engagement

ERIC Educational Resources Information Center

Siu, Oi-ling; Lu, Jia-fang; Brough, Paula; Lu, Chang-qin; Bakker, Arnold B.; Kalliath, Thomas; O'Driscoll, Michael; Phillips, David R.; Chen, Wei-qing; Lo, Danny; Sit, Cindy; Shi, Kan

2010-01-01

This article proposes a theoretical model of work-family enrichment and tests the mediating role of work engagement. The inclusion of work engagement extends prior research on work-family interface, and allows for examination of the effects of role resources (job resources, family support) on work-family enrichment. A two-wave survey was conducted…

What Contributes to Gifted Adolescent Females' Talent Development at a High-Achieving, Secondary Girls' School?

ERIC Educational Resources Information Center

Tweedale, Charlotte; Kronborg, Leonie

2015-01-01

The purpose of this research was to examine what contributes to gifted adolescent females' talent development at a high-achieving girls' school. Using Kronborg's (2010) Talent Development Model for Eminent Women as a theoretical framework, this research examined the conditions that supported and those that hindered the participants' talent…

A demographic study of the exponential distribution applied to uneven-aged forests

Treesearch

Jeffrey H. Gove

2016-01-01

A demographic approach based on a size-structured version of the McKendrick-Von Foerster equation is used to demonstrate a theoretical link between the population size distribution and the underlying vital rates (recruitment, mortality and diameter growth) for the population of individuals whose diameter distribution is negative exponential. This model supports the...

Beyond Hurt Feelings: Investigating Why Some Victims of Bullying Are at Greater Risk for Suicidal Ideation

ERIC Educational Resources Information Center

Bonanno, Rina A.; Hymel, Shelley

2010-01-01

This study investigated why some adolescents who are victimized through peer bullying are more negatively impacted than others. Drawing from research on peer victimization and suicidology, two theoretically derived models were investigated, one examining social hopelessness as a risk factor, the other examining social support as a protective…

Adopting a Resilience Practice Framework: A Case Study in What to Select and How to Implement

ERIC Educational Resources Information Center

Antcliff, Greg; Mildon, Robyn; Baldwin, Laura; Michaux, Annette; Nay, Cherie

2014-01-01

This paper describes the collaborative application of three theoretical models for supporting service planning (Hunter, 2006), programme planning (Chorpita et al, 2005a), and implementation (Meyers et al, 2012) to develop and implement a Resilience Practice Framework (RPF). Specifically, we (1) describe a theory of change framework (Hunter, 2006)…

Supervisory Styles and Graduate Student Creativity: The Mediating Roles of Creative Self-Efficacy and Intrinsic Motivation

ERIC Educational Resources Information Center

Gu, Jibao; He, Changqing; Liu, Hefu

2017-01-01

Based on social cognitive theory and leadership theory, the current study tests a theoretical model linking supervisory styles (i.e. supportive and directive) with graduate student creativity via psychological cognitive factors (specifically, creative self-efficacy and intrinsic motivation). Results from a sample of 216 graduate students of 1…

Content Analysis of Suicide Notes as a Test of the Motivational Component of the Existential-Constructivist Model of Suicide

ERIC Educational Resources Information Center

Rogers, James R.; Bromley, Jamie L.; McNally, Christopher J.; Lester, David

2007-01-01

A sample of 40 suicide notes were analyzed for motivational content in relation to an existential-constructivist theory of suicide. Results generally supported the 4 theoretical categories of somatic, relational, spiritual, and psychological motivations, with 39 notes having content that could be classified according to the aforementioned…

Assessing the Effectiveness of the Internationalization Process in Higher Education Institutions: A Case Study of Florida International University

ERIC Educational Resources Information Center

Iuspa, Flavia Eleonora

2010-01-01

The purpose of this study was to examine a Higher Education Institution's (HEI) process of internationalization. The theoretical model developed by Van Dijk and Miejer (1997) was used to review Florida International University (FIU)'s policy, support, and implementation dimensions and determine its position on the Internationalization Cube, and…

Conceptualising Student Voice in UK Higher Education: Four Theoretical Lenses

ERIC Educational Resources Information Center

Canning, John

2017-01-01

The "student voice" is highly profiled in UK higher education, yet highly under-theorised. Over the past 20 years UK universities have gone from a taxpayer-funded, free at the point of use model, to one supported through tuition fees via Government-backed loans. Subsequently, there is a growth of discourse about universities as…

Representing and querying now-relative relational medical data.

PubMed

Anselma, Luca; Piovesan, Luca; Stantic, Bela; Terenziani, Paolo

2018-03-01

Temporal information plays a crucial role in medicine. Patients' clinical records are intrinsically temporal. Thus, in Medical Informatics there is an increasing need to store, support and query temporal data (particularly in relational databases), in order, for instance, to supplement decision-support systems. In this paper, we show that current approaches to relational data have remarkable limitations in the treatment of "now-relative" data (i.e., data holding true at the current time). This can severely compromise their applicability in general, and specifically in the medical context, where "now-relative" data are essential to assess the current status of the patients. We propose a theoretically grounded and application-independent relational approach to cope with now-relative data (which can be paired, e.g., with different decision support systems) overcoming such limitations. We propose a new temporal relational representation, which is the first relational model coping with the temporal indeterminacy intrinsic in now-relative data. We also propose new temporal algebraic operators to query them, supporting the distinction between possible and necessary time, and Allen's temporal relations between data. We exemplify the impact of our approach, and study the theoretical and computational properties of the new representation and algebra. Copyright © 2018 Elsevier B.V. All rights reserved.

Agent-Centric Approach for Cybersecurity Decision-Support with Partial Observability

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

Tipireddy, Ramakrishna; Chatterjee, Samrat; Paulson, Patrick R.

Generating automated cyber resilience policies for real-world settings is a challenging research problem that must account for uncertainties in system state over time and dynamics between attackers and defenders. In addition to understanding attacker and defender motives and tools, and identifying “relevant” system and attack data, it is also critical to develop rigorous mathematical formulations representing the defender’s decision-support problem under uncertainty. Game-theoretic approaches involving cyber resource allocation optimization with Markov decision processes (MDP) have been previously proposed in the literature. Moreover, advancements in reinforcement learning approaches have motivated the development of partially observable stochastic games (POSGs) in various multi-agentmore » problem domains with partial information. Recent advances in cyber-system state space modeling have also generated interest in potential applicability of POSGs for cybersecurity. However, as is the case in strategic card games such as poker, research challenges using game-theoretic approaches for practical cyber defense applications include: 1) solving for equilibrium and designing efficient algorithms for large-scale, general problems; 2) establishing mathematical guarantees that equilibrium exists; 3) handling possible existence of multiple equilibria; and 4) exploitation of opponent weaknesses. Inspired by advances in solving strategic card games while acknowledging practical challenges associated with the use of game-theoretic approaches in cyber settings, this paper proposes an agent-centric approach for cybersecurity decision-support with partial system state observability.« less

A quantitative dynamic systems model of health-related quality of life among older adults

PubMed Central

Roppolo, Mattia; Kunnen, E Saskia; van Geert, Paul L; Mulasso, Anna; Rabaglietti, Emanuela

2015-01-01

Health-related quality of life (HRQOL) is a person-centered concept. The analysis of HRQOL is highly relevant in the aged population, which is generally suffering from health decline. Starting from a conceptual dynamic systems model that describes the development of HRQOL in individuals over time, this study aims to develop and test a quantitative dynamic systems model, in order to reveal the possible dynamic trends of HRQOL among older adults. The model is tested in different ways: first, with a calibration procedure to test whether the model produces theoretically plausible results, and second, with a preliminary validation procedure using empirical data of 194 older adults. This first validation tested the prediction that given a particular starting point (first empirical data point), the model will generate dynamic trajectories that lead to the observed endpoint (second empirical data point). The analyses reveal that the quantitative model produces theoretically plausible trajectories, thus providing support for the calibration procedure. Furthermore, the analyses of validation show a good fit between empirical and simulated data. In fact, no differences were found in the comparison between empirical and simulated final data for the same subgroup of participants, whereas the comparison between different subgroups of people resulted in significant differences. These data provide an initial basis of evidence for the dynamic nature of HRQOL during the aging process. Therefore, these data may give new theoretical and applied insights into the study of HRQOL and its development with time in the aging population. PMID:26604722

On the complex relationship between energy expenditure and longevity: Reconciling the contradictory empirical results with a simple theoretical model.

PubMed

Hou, Chen; Amunugama, Kaushalya

2015-07-01

The relationship between energy expenditure and longevity has been a central theme in aging studies. Empirical studies have yielded controversial results, which cannot be reconciled by existing theories. In this paper, we present a simple theoretical model based on first principles of energy conservation and allometric scaling laws. The model takes into considerations the energy tradeoffs between life history traits and the efficiency of the energy utilization, and offers quantitative and qualitative explanations for a set of seemingly contradictory empirical results. We show that oxidative metabolism can affect cellular damage and longevity in different ways in animals with different life histories and under different experimental conditions. Qualitative data and the linearity between energy expenditure, cellular damage, and lifespan assumed in previous studies are not sufficient to understand the complexity of the relationships. Our model provides a theoretical framework for quantitative analyses and predictions. The model is supported by a variety of empirical studies, including studies on the cellular damage profile during ontogeny; the intra- and inter-specific correlations between body mass, metabolic rate, and lifespan; and the effects on lifespan of (1) diet restriction and genetic modification of growth hormone, (2) the cold and exercise stresses, and (3) manipulations of antioxidant. Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Impact of Managers' Coaching Conversations on Staff Knowledge Use and Performance in Long-Term Care Settings.

PubMed

Cummings, Greta G; Hewko, Sarah J; Wang, Mengzhe; Wong, Carol A; Laschinger, Heather K Spence; Estabrooks, Carole A

2018-02-01

Extended lifespans and complex resident care needs have amplified resource demands on nursing homes. Nurse managers play an important role in staff job satisfaction, research use, and resident outcomes. Coaching skills, developed through leadership skill-building, have been shown to be of value in nursing. To test a theoretical model of nursing home staff perceptions of their work context, their managers' use of coaching conversations, and their use of instrumental, conceptual and persuasive research. Using a two-group crossover design, 33 managers employed in seven Canadian nursing homes were invited to attend a 2-day coaching development workshop. Survey data were collected from managers and staff at three time points; we analyzed staff data (n = 333), collected after managers had completed the workshop. We used structural equation modeling to test our theoretical model of contextual characteristics as causal variables, managers' characteristics, and coaching behaviors as mediating variables and staff use of research, job satisfaction, and burnout as outcome variables. The theoretical model fit the data well (χ 2 = 58, df = 43, p = .06) indicating no significant differences between data and model-implied matrices. Resonant leadership (a relational approach to influencing change) had the strongest significant relationship with manager support, which in turn influenced frequency of coaching conversations. Coaching conversations had a positive, non-significant relationship with staff persuasive use of research, which in turn significantly increased instrumental research use. Importantly, coaching conversations were significantly, negatively related to job satisfaction. Our findings add to growing research exploring the role of context and leadership in influencing job satisfaction and use of research by healthcare practitioners. One-on-one coaching conversations may be difficult for staff not used to participating in such conversations. Resonant leadership, as expected, has a significant impact on manager support and job satisfaction among nursing home staff. © 2017 Sigma Theta Tau International.

Computerised decision support in physical activity interventions: A systematic literature review.

PubMed

Triantafyllidis, Andreas; Filos, Dimitris; Claes, Jomme; Buys, Roselien; Cornelissen, Véronique; Kouidi, Evangelia; Chouvarda, Ioanna; Maglaveras, Nicos

2018-03-01

The benefits of regular physical activity for health and quality of life are unarguable. New information, sensing and communication technologies have the potential to play a critical role in computerised decision support and coaching for physical activity. We provide a literature review of recent research in the development of physical activity interventions employing computerised decision support, their feasibility and effectiveness in healthy and diseased individuals, and map out challenges and future research directions. We searched the bibliographic databases of PubMed and Scopus to identify physical activity interventions with computerised decision support utilised in a real-life context. Studies were synthesized according to the target user group, the technological format (e.g., web-based or mobile-based) and decision-support features of the intervention, the theoretical model for decision support in health behaviour change, the study design, the primary outcome, the number of participants and their engagement with the intervention, as well as the total follow-up duration. From the 24 studies included in the review, the highest percentage (n = 7, 29%) targeted sedentary healthy individuals followed by patients with prediabetes/diabetes (n = 4, 17%) or overweight individuals (n = 4, 17%). Most randomized controlled trials reported significantly positive effects of the interventions, i.e., increase in physical activity (n = 7, 100%) for 7 studies assessing physical activity measures, weight loss (n = 3, 75%) for 4 studies assessing diet, and reductions in glycosylated hemoglobin (n = 2, 66%) for 3 studies assessing glycose concentration. Accelerometers/pedometers were used in almost half of the studies (n = 11, 46%). Most adopted decision support features included personalised goal-setting (n = 16, 67%) and motivational feedback sent to the users (n = 15, 63%). Fewer adopted features were integration with electronic health records (n = 3, 13%) and alerts sent to caregivers (n = 4, 17%). Theoretical models of decision support in health behaviour to drive the development of the intervention were not reported in most studies (n = 14, 58%). Interventions employing computerised decision support have the potential to promote physical activity and result in health benefits for both diseased and healthy individuals, and help healthcare providers to monitor patients more closely. Objectively measured activity through sensing devices, integration with clinical systems used by healthcare providers and theoretical frameworks for health behaviour change need to be employed in a larger scale in future studies in order to realise the development of evidence-based computerised systems for physical activity monitoring and coaching. Copyright © 2017 Elsevier B.V. All rights reserved.

The Interaction-Activity Connection

NASA Technical Reports Server (NTRS)

Borne, Kirk D.

1996-01-01

A review is presented of the numerous studies that have been undertaken to investigate the likely interaction-activity connection among galaxies. Both observational evidence and theoretical supporting models are reviewed. Some specific examples of "interactive" galaxies from the author's own research are presented: (a) the collision-induced AGN (Active Galactic Nuclei) activity in the radio jet source 3C278; and (b) the collision-induced starburst activity in the spectacular "Cartwheel" ring galaxy. Some comments are offered concerning some of the more promising theoretical investigations that are now taking place. A few words of warning are also offered about the possible misinterpretation of putative collision-induced morphologies among some galaxy samples.

Soft silicone rubber in phononic structures: Correct elastic moduli

NASA Astrophysics Data System (ADS)

Still, Tim; Oudich, M.; Auerhammer, G. K.; Vlassopoulos, D.; Djafari-Rouhani, B.; Fytas, G.; Sheng, P.

2013-09-01

We report on a combination of experiments to determine the elastic moduli of a soft poly (dimethylsiloxane) rubber that was utilized in a smart experiment on resonant phononic modes [Liu , ScienceSCIEAS0036-807510.1126/science.289.5485.1734 289, 1734 (2000)] and whose reported moduli became widely used as a model system in theoretical calculations of phononic materials. We found that the most peculiar hallmark of these values, an extremely low longitudinal sound velocity, is not supported by our experiments. Anyhow, performing theoretical band structure calculations, we can reproduce the surprising experimental findings of Liu even utilizing the correct mechanical parameters. Thus, the physical conclusions derived in the theoretical works do not require the use of an extremely low longitudinal velocity, but can be reproduced assuming only a low value of the shear modulus, in agreement with our experiments.

HANFORD DST THERMAL & SEISMIC PROJECT ANSYS BENCHMARK ANALYSIS OF SEISMIC INDUCED FLUID STRUCTURE INTERACTION IN A HANFORD DOUBLE SHELL PRIMARY TANK

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

MACKEY, T.C.

M&D Professional Services, Inc. (M&D) is under subcontract to Pacific Northwest National Laboratories (PNNL) to perform seismic analysis of the Hanford Site Double-Shell Tanks (DSTs) in support of a project entitled ''Double-Shell Tank (DSV Integrity Project-DST Thermal and Seismic Analyses)''. The overall scope of the project is to complete an up-to-date comprehensive analysis of record of the DST System at Hanford in support of Tri-Party Agreement Milestone M-48-14. The work described herein was performed in support of the seismic analysis of the DSTs. The thermal and operating loads analysis of the DSTs is documented in Rinker et al. (2004). Themore » overall seismic analysis of the DSTs is being performed with the general-purpose finite element code ANSYS. The overall model used for the seismic analysis of the DSTs includes the DST structure, the contained waste, and the surrounding soil. The seismic analysis of the DSTs must address the fluid-structure interaction behavior and sloshing response of the primary tank and contained liquid. ANSYS has demonstrated capabilities for structural analysis, but the capabilities and limitations of ANSYS to perform fluid-structure interaction are less well understood. The purpose of this study is to demonstrate the capabilities and investigate the limitations of ANSYS for performing a fluid-structure interaction analysis of the primary tank and contained waste. To this end, the ANSYS solutions are benchmarked against theoretical solutions appearing in BNL 1995, when such theoretical solutions exist. When theoretical solutions were not available, comparisons were made to theoretical solutions of similar problems and to the results from Dytran simulations. The capabilities and limitations of the finite element code Dytran for performing a fluid-structure interaction analysis of the primary tank and contained waste were explored in a parallel investigation (Abatt 2006). In conjunction with the results of the global ANSYS analysis reported in Carpenter et al. (2006), the results of the two investigations will be compared to help determine if a more refined sub-model of the primary tank is necessary to capture the important fluid-structure interaction effects in the tank and if so, how to best utilize a refined sub-model of the primary tank. Both rigid tank and flexible tank configurations were analyzed with ANSYS. The response parameters of interest are total hydrodynamic reaction forces, impulsive and convective mode frequencies, waste pressures, and slosh heights. To a limited extent: tank stresses are also reported. The results of this study demonstrate that the ANSYS model has the capability to adequately predict global responses such as frequencies and overall reaction forces. Thus, the model is suitable for predicting the global response of the tank and contained waste. On the other hand, while the ANSYS model is capable of adequately predicting waste pressures and primary tank stresses in a large portion of the waste tank, the model does not accurately capture the convective behavior of the waste near the free surface, nor did the model give accurate predictions of slosh heights. Based on the ability of the ANSYS benchmark model to accurately predict frequencies and global reaction forces and on the results presented in Abatt, et al. (2006), the global ANSYS model described in Carpenter et al. (2006) is sufficient for the seismic evaluation of all tank components except for local areas of the primary tank. Due to the limitations of the ANSYS model in predicting the convective response of the waste, the evaluation of primary tank stresses near the waste free surface should be supplemented by results from an ANSYS sub-model of the primary tank that incorporates pressures from theoretical solutions or from Dytran solutions. However, the primary tank is expected to have low demand to capacity ratios in the upper wall. Moreover, due to the less than desired mesh resolution in the primary tank knuckle of the global ANSYS model, the evaluation of the primary tank stresses in the lower knuckle should be supplemented by results from a more refined ANSYS sub-model of the primary tank that incorporates pressures from theoretical solutions or from Dytran solutions.« less

Mitotic wavefronts mediated by mechanical signaling in early Drosophila embryos

NASA Astrophysics Data System (ADS)

Kang, Louis; Idema, Timon; Liu, Andrea; Lubensky, Tom

2013-03-01

Mitosis in the early Drosophila embryo demonstrates spatial and temporal correlations in the form of wavefronts that travel across the embryo in each cell cycle. This coordinated phenomenon requires a signaling mechanism, which we suggest is mechanical in origin. We have constructed a theoretical model that supports nonlinear wavefront propagation in a mechanically-excitable medium. Previously, we have shown that this model captures quantitatively the wavefront speed as it varies with cell cycle number, for reasonable values of the elastic moduli and damping coefficient of the medium. Now we show that our model also captures the displacements of cell nuclei in the embryo in response to the traveling wavefront. This new result further supports that mechanical signaling may play an important role in mediating mitotic wavefronts.

Experimental Verification of Same Simple Equilibrium Models of Masonry Shear Walls

NASA Astrophysics Data System (ADS)

Radosław, Jasiński

2017-10-01

This paper contains theoretical fundamentals of strut and tie models, used in unreinforced horizontal shear walls. Depending on support conditions and wall loading, we can distinguish models with discrete bars when point load is applied to the wall (type I model) or with continuous bars (type II model) when load is uniformly distributed at the wall boundary. The main part of this paper compares calculated results with the own tests on horizontal shear walls made of solid brick, silicate elements and autoclaved aerated concrete. The tests were performed in Poland. The model required some modifications due to specific load and static diagram.

Choosing to Live or Die: Online Narratives of Recovering from Methamphetamine Abuse.

PubMed

Obong'o, Christopher O; Alexander, Adam C; Chavan, Prachi P; Dillon, Patrick J; Kedia, Satish K

2017-01-01

The goal of this study is to explore motivating factors for recovering from methamphetamine abuse. The source of data was 202 anonymous letters and stories submitted to an online support platform for methamphetamine users. Qualitative data were analyzed in Dedoose software using grounded theory methodology. Ten primary motivating factors for recovering from methamphetamine abuse were identified and mapped onto four constructs from the Health Belief Model: (1) perceived susceptibility (learning from others and learning from self); (2) perceived severity (fear of death and declining health); (3) perceived benefits (reconnecting with family, reconnecting with society, and recovering self-esteem); and (4) cues to action (hitting rock bottom, finding God, and becoming pregnant). By using data from an online support group and categorizing emerging themes within a theoretical framework, findings from this study provide a comprehensive understanding of factors involved in recovery from methamphetamine abuse and offer further insights in developing theoretically informed interventions for methamphetamine users. This study suggests the utility of online platforms for obtaining anonymous but unique experiences about drug abuse and recovery. Findings may benefit healthcare professionals, counselors, and researchers by helping to develop theoretically informed interventions for methamphetamine abuse.

Queueing theoretic analysis of labor and delivery : Understanding management styles and C-section rates.

PubMed

Gombolay, Matthew; Golen, Toni; Shah, Neel; Shah, Julie

2017-09-04

Childbirth is a complex clinical service requiring the coordinated support of highly trained healthcare professionals as well as management of a finite set of critical resources (such as staff and beds) to provide safe care. The mode of delivery (vaginal delivery or cesarean section) has a significant effect on labor and delivery resource needs. Further, resource management decisions may impact the amount of time a physician or nurse is able to spend with any given patient. In this work, we employ queueing theory to model one year of transactional patient information at a tertiary care center in Boston, Massachusetts. First, we observe that the M/G/∞ model effectively predicts patient flow in an obstetrics department. This model captures the dynamics of labor and delivery where patients arrive randomly during the day, the duration of their stay is based on their individual acuity, and their labor progresses at some rate irrespective of whether they are given a bed. Second, using our queueing theoretic model, we show that reducing the rate of cesarean section - a current quality improvement goal in American obstetrics - may have important consequences with regard to the resource needs of a hospital. We also estimate the potential financial impact of these resource needs from the hospital perspective. Third, we report that application of our model to an analysis of potential patient coverage strategies supports the adoption of team-based care, in which attending physicians share responsibilities for patients.

Determinants for the success of regional ICT ventures: a close examination of South Korea.

PubMed

Park, Eunil; Kim, Ki Joon; Kwon, Sang Jib; Ohm, Jay Y; Del Pobil, Angel P; Yoo, Kyeongsik

2016-01-01

This study identifies the key motivational factors in enhancing economic performance and increasing new job opportunities for information and communication technology ventures (ICTVs) in South Korea and examines their potential causal relationships through structural equation modeling analysis on data collected from over 200 ICTVs located in Daedeok Innopolis. The results indicate that the economic performance of ICTVs is determined mainly by government support, innovation effort, and private equity and support. Government support and innovation effort are also positively associated with new job opportunities. The theoretical, industrial implications of the key findings, and recommendations for the Korean government are discussed.

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

PubMed

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.

Pulsed photothermal interferometry for spectroscopic gas detection with hollow-core optical fibre

PubMed Central

Lin, Yuechuan; Jin, Wei; Yang, Fan; Ma, Jun; Wang, Chao; Ho, Hoi Lut; Liu, Yang

2016-01-01

Gas detection with hollow-core photonic bandgap fibre (HC-PBF) and pulsed photothermal (PT) interferometry spectroscopy are studied theoretically and experimentally. A theoretical model is developed and used to compute the gas-absorption-induced temperature and phase modulation in a HC-PBF filled with low-concentration of C2H2 in nitrogen. The PT phase modulation dynamics for different pulse duration, peak power and energy of pump beam are numerically modelled, which are supported by the experimental results obtained around the P(9) absorption line of C2H2 at 1530.371 nm. Thermal conduction is identified as the main process responsible for the phase modulation dynamics. For a constant peak pump power level, the phase modulation is found to increase with pulse duration up to ~1.2 μs, while it increases with decreasing pulse duration for a constant pulse energy. It is theoretically possible to achieve ppb level detection of C2H2 with ~1 m length HC-PBF and a pump beam with ~10 ns pulse duration and ~100 nJ pulse energy. PMID:28009011

Pulsed photothermal interferometry for spectroscopic gas detection with hollow-core optical fibre.

PubMed

Lin, Yuechuan; Jin, Wei; Yang, Fan; Ma, Jun; Wang, Chao; Ho, Hoi Lut; Liu, Yang

2016-12-23

Gas detection with hollow-core photonic bandgap fibre (HC-PBF) and pulsed photothermal (PT) interferometry spectroscopy are studied theoretically and experimentally. A theoretical model is developed and used to compute the gas-absorption-induced temperature and phase modulation in a HC-PBF filled with low-concentration of C 2 H 2 in nitrogen. The PT phase modulation dynamics for different pulse duration, peak power and energy of pump beam are numerically modelled, which are supported by the experimental results obtained around the P(9) absorption line of C 2 H 2 at 1530.371 nm. Thermal conduction is identified as the main process responsible for the phase modulation dynamics. For a constant peak pump power level, the phase modulation is found to increase with pulse duration up to ~1.2 μs, while it increases with decreasing pulse duration for a constant pulse energy. It is theoretically possible to achieve ppb level detection of C 2 H 2 with ~1 m length HC-PBF and a pump beam with ~10 ns pulse duration and ~100 nJ pulse energy.

Excited State Charge Transfer reaction with dual emission from 5-(4-dimethylamino-phenyl)-penta-2,4-dienenitrile: Spectral measurement and theoretical density functional theory calculation

NASA Astrophysics Data System (ADS)

Jana, Sankar; Dalapati, Sasanka; Ghosh, Shalini; Kar, Samiran; Guchhait, Nikhil

2011-07-01

The excited state intramolecular charge transfer process in donor-chromophore-acceptor system 5-(4-dimethylamino-phenyl)-penta-2,4-dienenitrile (DMAPPDN) has been investigated by steady state absorption and emission spectroscopy in combination with Density Functional Theory (DFT) calculations. This flexible donor acceptor molecule DMAPPDN shows dual fluorescence corresponding to emission from locally excited and charge transfer state in polar solvent. Large solvatochromic emission shift, effect of variation of pH and HOMO-LUMO molecular orbital pictures support excited state intramolecular charge transfer process. The experimental findings have been correlated with the calculated structure and potential energy surfaces based on the Twisted Intramolecular Charge Transfer (TICT) model obtained at DFT level using B3LYP functional and 6-31+G( d, p) basis set. The theoretical potential energy surfaces for the excited states have been generated in vacuo and acetonitrile solvent using Time Dependent Density Functional Theory (TDDFT) and Time Dependent Density Functional Theory Polarized Continuum Model (TDDFT-PCM) method, respectively. All the theoretical results show well agreement with the experimental observations.

Experimental and theoretical charge density studies at subatomic resolution.

PubMed

Fischer, A; Tiana, D; Scherer, W; Batke, K; Eickerling, G; Svendsen, H; Bindzus, N; Iversen, B B

2011-11-17

Analysis of accurate experimental and theoretical structure factors of diamond and silicon reveals that the contraction of the core shell due to covalent bond formation causes significant perturbations of the total charge density that cannot be ignored in precise charge density studies. We outline that the nature and origin of core contraction/expansion and core polarization phenomena can be analyzed by experimental studies employing an extended Hansen-Coppens multipolar model. Omission or insufficient treatment of these subatomic charge density phenomena might yield erroneous thermal displacement parameters and high residual densities in multipolar refinements. Our detailed studies therefore suggest that the refinement of contraction/expansion and population parameters of all atomic shells is essential to the precise reconstruction of electron density distributions by a multipolar model. Furthermore, our results imply that also the polarization of the inner shells needs to be adopted, especially in cases where second row or even heavier elements are involved in covalent bonding. These theoretical studies are supported by direct multipolar refinements of X-ray powder diffraction data of diamond obtained from a third-generation synchrotron-radiation source (SPring-8, BL02B2).

Modeling the effects of inflammation in bone fracture healing

NASA Astrophysics Data System (ADS)

Kojouharov, H. V.; Trejo, I.; Chen-Charpentier, B. M.

2017-10-01

A new mathematical model is presented to study the early inflammatory effects in bone healing. It consists of a system of nonlinear ordinary differential equations that represents the interactions among macrophages, mesenchymal stem cells, and osteoblasts. A qualitative analysis of the model is performed to determine the equilibria and their corresponding stability properties. A set of numerical simulations is performed to support the theoretical results. The model is also used to numerically monitor the evolution of a broken bone for different types of fractures and to explore possible treatments to accelerate bone healing by administrating anti-inflammatory drugs.

Analysis of the coupling efficiency of a tapered space receiver with a calculus mathematical model

NASA Astrophysics Data System (ADS)

Hu, Qinggui; Mu, Yining

2018-03-01

We establish a calculus mathematical model to study the coupling characteristics of tapered optical fibers in a space communications system, and obtained the coupling efficiency equation. Then, using MATLAB software, the solution was calculated. After this, the sample was produced by the mature flame-brush technique. The experiment was then performed, and the results were in accordance with the theoretical analysis. This shows that the theoretical analysis was correct and indicates that a tapered structure could improve its tolerance with misalignment. Project supported by The National Natural Science Foundation of China (grant no. 61275080); 2017 Jilin Province Science and Technology Development Plan-Science and Technology Innovation Fund for Small and Medium Enterprises (20170308029HJ); ‘thirteen five’ science and technology research project of the Department of Education of Jilin 2016 (16JK009).

Modeling of rolling element bearing mechanics. Theoretical manual

NASA Technical Reports Server (NTRS)

Merchant, David H.; Greenhill, Lyn M.

1994-01-01

This report documents the theoretical basis for the Rolling Element Bearing Analysis System (REBANS) analysis code which determines the quasistatic response to external loads or displacement of three types of high-speed rolling element bearings: angular contact ball bearings; duplex angular contact ball bearings; and cylindrical roller bearings. The model includes the effects of bearing ring and support structure flexibility. It is comprised of two main programs: the Preprocessor for Bearing Analysis (PREBAN) which creates the input files for the main analysis program; and Flexibility Enhanced Rolling Element Bearing Analysis (FEREBA), the main analysis program. A companion report addresses the input instructions for and features of the computer codes. REBANS extends the capabilities of the SHABERTH (Shaft and Bearing Thermal Analysis) code to include race and housing flexibility, including such effects as dead band and preload springs.

Center for Theoretical Underground Physics and Related Areas - CETUP*2013 Summer Program

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

Szczerbinska, Barbara

In response to an increasing interest in experiments conducted at deep underground facilities around the world, in 2010 the theory community has proposed a new initiative - a Center for Theoretical Underground Physics and Related Areas (CETUP*). The main goal of CETUP* is to bring together people with different talents and skills to address the most exciting questions in particle and nuclear physics, astrophysics, geosciences, and geomicrobiology. Scientists invited to participate in the program do not only provide theoretical support to the underground science, they also examine underlying universal questions of the 21 st century including: What is dark matter?,more » What are the masses of neutrinos?, How have neutrinos shaped the evolution of the universe?, How were the elements from iron to uranium made?, What is the origin and thermal history of the Earth? The mission of the CETUP* is to promote an organized research in physics, astrophysics, geoscience, geomicrobiology and other fields related to the underground science via individual and collaborative research in dynamic atmosphere of intense scientific interactions. Our main goal is to bring together scientists scattered around the world, promote the deep underground science and provide a stimulating environment for creative thinking and open communication between researches of varying ages and nationalities. CETUP*2014 included 5 week long program (June 24 – July 26, 2013) covering various theoretical and experimental aspects of Dark Matter, Neutrino Physics and Astrophysics. Two week long session focused on Dark Matter (June 24-July 6) was followed by two week long program on Neutrino Physics and Astrophysics (July 15-26). The VII th International Conference on Interconnections between Particle Physics and Cosmology (PPC) was sandwiched between these sessions (July 8-13) covering the subjects of dark matter, neutrino physics, gravitational waves, collider physics and other from both theoretical end experimental aspects. PPC was initiated at Texas A&M University in 2007 and travelled to many places which include Geneva, Turin, Seoul (S. Korea) etc. during the last 5 years before coming back to USA. The objectives of CETUP* and PPC were to analyze the connection between dark matter and particle physics models, discuss the connections among dark matter, grand unification models and recent neutrino results and predictions for possible experiments, develop a theoretical understanding of the three-neutrino oscillation parameters, provide a stimulating venue for exchange of scientific ideas among experts in neutrino physics and unification, connect with venues for public education outreach to communicate the importance of dark matter, neutrino research, and support of investment in science education, support mission of the Snowmass meeting and allow for extensive discussions of the ideas crucial for the future of high energy physics. The selected subjects represented the forefront of research topics in particle and nuclear physics, for example: recent precise measurements of all the neutrino mixing angles (that necessitate a theoretical roadmap for future experiments) or understanding of the nature of dark matter (that allows us to comprehend the composition of the cosmos better). All the covered topics are considered as a base for new physics beyond the Standard Model of particle physics.« less

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

PubMed

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

2015-01-01

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

The propagation of sound in tunnels

NASA Astrophysics Data System (ADS)

Li, Kai Ming; Iu, King Kwong

2002-11-01

The sound propagation in tunnels is addressed theoretically and experimentally. In many previous studies, the image source method is frequently used. However, these early theoretical models are somewhat inadequate because the effect of multiple reflections in long enclosures is often modeled by the incoherent summation of contributions from all image sources. Ignoring the phase effect, these numerical models are unlikely to be satisfactory for predicting the intricate interference patterns due to contributions from each image source. In the present paper, the interference effect is incorporated by summing the contributions from the image sources coherently. To develop a simple numerical model, tunnels are represented by long rectangular enclosures with either geometrically reflecting or impedance boundaries. Scale model experiments are conducted for the validation of the numerical model. In some of the scale model experiments, the enclosure walls are lined with a carpet for simulating the impedance boundary condition. Large-scale outdoor measurements have also been conducted in two tunnels designed originally for road traffic use. It has been shown that the proposed numerical model agrees reasonably well with experimental data. [Work supported by the Research Grants Council, The Industry Department, NAP Acoustics (Far East) Ltd., and The Hong Kong Polytechnic University.

Why the long hours? Job demands and social exchange dynamics.

PubMed

Genin, Emilie; Haines, Victor Y; Pelletier, David; Rousseau, Vincent; Marchand, Alain

2016-11-22

This study investigates the determinants of long working hours from the perspectives of the demand-control model [Karasek, 1979] and social exchange theory [Blau, 1964; Goulder, 1960]. These two theoretical perspectives are tested to understand why individuals work longer (or shorter) hours. The hypotheses are tested with a representative sample of 1,604 employed Canadians. In line with Karasek's model, the results support that high job demands are positively associated with longer work hours. The social exchange perspective would predict a positive association between skill discretion and work hours. This hypothesis was supported for individuals with a higher education degree. Finally, the results support a positive association between active jobs and longer work hours. Our research suggests that job demands and social exchange dynamics need to be considered together in the explanation of longer (or shorter) work hours.

Something for nothing: understanding purchasing behaviors in social virtual environments.

PubMed

Chung, Donghun

2005-12-01

The present paper is composed of two studies. The first study explored the variables influencing the purchase of avatar-related products through the avatar users' survey research. This proposed a theoretical model of the purchase of avatar-related products using attitude toward an avatar, subjective norm, self-presentation, identification, and immersion. Although significant relationships were found for the individual links, the model was not supported. The second study focused on which variables predict the intention to use avatar-related products. A model was tested with avatar non-users. Results indicated that all relationships among variables in the Technology Acceptance Model (TAM), such as perceived ease of use of avatar, perceived usefulness of avatar, attitude toward using avatar, and intention to use avatar-related products, were strongly supported, as was the link between Internet self-efficacy and perceived ease of use of avatar. Also, the peer groups' subjective norm component which was a unique variable successfully predicted intention to use avatar-related products. Overall, all hypotheses were supported and the data were judged to be consistent with the model.

Evaluation of teledermatology adoption by health-care professionals using a modified Technology Acceptance Model.

PubMed

Orruño, Estibalitz; Gagnon, Marie Pierre; Asua, José; Ben Abdeljelil, Anis

2011-01-01

We examined the main factors affecting the intention of physicians to use teledermatology using a modified Technology Acceptance Model (TAM). The investigation was carried out during a teledermatology pilot study conducted in Spain. A total of 276 questionnaires were sent to physicians by email and 171 responded (62%). Cronbach's alpha was acceptably high for all constructs. Theoretical variables were well correlated with each other and with the dependent variable (Intention to Use). Logistic regression indicated that the original TAM model was good at predicting physicians' intention to use teledermatology and that the variables Perceived Usefulness and Perceived Ease of Use were both significant (odds ratios of 8.4 and 7.4, respectively). When other theoretical variables were added, the model was still significant and it also became more powerful. However, the only significant predictor in the modified model was Facilitators with an odds ratio of 9.9. Thus the TAM was good at predicting physicians' intention to use teledermatology. However, the most important variable was the perception of Facilitators to using the technology (e.g. infrastructure, training and support).

Linking Theoretical Decision-making Mechanisms in the Simon Task with Electrophysiological Data: A Model-based Neuroscience Study in Humans.

PubMed

Servant, Mathieu; White, Corey; Montagnini, Anna; Burle, Borís

2016-10-01

A current challenge for decision-making research is in extending models of simple decisions to more complex and ecological choice situations. Conflict tasks (e.g., Simon, Stroop, Eriksen flanker) have been the focus of much interest, because they provide a decision-making context representative of everyday life experiences. Modeling efforts have led to an elaborated drift diffusion model for conflict tasks (DMC), which implements a superimposition of automatic and controlled decision activations. The DMC has proven to capture the diversity of behavioral conflict effects across various task contexts. This study combined DMC predictions with EEG and EMG measurements to test a set of linking propositions that specify the relationship between theoretical decision-making mechanisms involved in the Simon task and brain activity. Our results are consistent with a representation of the superimposed decision variable in the primary motor cortices. The decision variable was also observed in the EMG activity of response agonist muscles. These findings provide new insight into the neurophysiology of human decision-making. In return, they provide support for the DMC model framework.

Changing Views on Intergenerational Ties

PubMed Central

Fingerman, Karen L.; Sechrist, Jori; Birditt, Kira

2015-01-01

Ties to parents or grown children may be the most important social relationships in an adult’s life. Research examining intergenerational relationships has focused on three broader topics: (a) the strength of emotional bonds, (b) exchanges of social support, and (c) the effects of the relationship on individual well-being. This review considers some of the major theoretical developments in the field including solidarity and intergenerational ambivalence theory as well as the newly developed multidimensional model of support. We also consider weaknesses in the research and theories to date and provide suggestions for future research. PMID:23037718

Empirical study of fuzzy compatibility measures and aggregation operators

NASA Astrophysics Data System (ADS)

Cross, Valerie V.; Sudkamp, Thomas A.

1992-02-01

Two fundamental requirements for the generation of support using incomplete and imprecise information are the ability to measure the compatibility of discriminatory information with domain knowledge and the ability to fuse information obtained from disparate sources. A generic architecture utilizing the generalized fuzzy relational database model has been developed to empirically investigate the support generation capabilities of various compatibility measures and aggregation operators. This paper examines the effectiveness of combinations of compatibility measures from the set-theoretic, geometric distance, and logic- based classes paired with t-norm and generalized mean families of aggregation operators.

Listening to nursing leaders: using national database of nursing quality indicators data to study excellence in nursing leadership.

PubMed

Anderson, Barbara Jo; Manno, Martin; O'Connor, Pricilla; Gallagher, Eileen

2010-04-01

There are varying and overlapping leadership characteristics that exemplify excellence in nursing leadership. To assess aspects of leadership that helps create a healthy work environment that supports nurses' provision of quality care at the bedside, the authors used a national survey instrument to examine the characteristics of nurse managers identified as excellent nurse leaders by their staff. The authors discuss their findings and a proposed theoretical model to explain specific nursing leadership characteristics that support staff nurse job satisfaction and retention.

Bonding in uranium(V) hexafluoride based on the experimental electron density distribution measured at 20 K

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

Gianopoulos, Christopher G.; Zhurov, Vladimir V.; Minasian, Stefan G.

The electron density distribution of [PPh 4][UF 6] was obtained from high-resolution X-ray diffraction data measured at 20 K. The electron density was modeled with an augmented Hansen–Coppens multipolar formalism. Topological analysis reveals that the U–F bond is of incipient covalent nature. Theoretical calculations add further support to the bonding description gleaned from the experimental model. The impact of the uranium anomalous dispersion terms on the refinement is also discussed.

DNA nanosensor surface grafting and salt dependence

NASA Astrophysics Data System (ADS)

Carvalho, B. G.; Fagundes, J.; Martin, A. A.; Raniero, L.; Favero, P. P.

2013-02-01

In this paper we investigated the Paracoccidoides brasiliensis fungus nanosensor by simulations of simple strand DNA grafting on gold nanoparticle. In order to improve the knowledge of nanoparticle environment, the addiction of salt solution was studied at the models proposed by us. Nanoparticle and DNA are represented by economic models validated by us in this paper. In addition, the DNA grafting and salt influences are evaluated by adsorption and bond energies calculations. This theoretical evaluation gives support to experimental diagnostics techniques of diseases.

Fermion mass without symmetry breaking

DOE PAGES

Catterall, Simon

2016-01-20

We examine a model of reduced staggered fermions in three dimensions interacting through an SO (4) invariant four fermion interaction. The model is similar to that considered in a recent paper by Ayyer and Chandrasekharan. We present theoretical arguments and numerical evidence which support the idea that the system develops a mass gap for sufficiently strong four fermi coupling without producing a symmetry breaking fermion bilinear condensate. As a result, massless and massive phases appear to be separated by a continuous phase transition.

Bonding in uranium(V) hexafluoride based on the experimental electron density distribution measured at 20 K

DOE PAGES

Gianopoulos, Christopher G.; Zhurov, Vladimir V.; Minasian, Stefan G.; ...

2017-02-06

The electron density distribution of [PPh 4][UF 6] was obtained from high-resolution X-ray diffraction data measured at 20 K. The electron density was modeled with an augmented Hansen–Coppens multipolar formalism. Topological analysis reveals that the U–F bond is of incipient covalent nature. Theoretical calculations add further support to the bonding description gleaned from the experimental model. The impact of the uranium anomalous dispersion terms on the refinement is also discussed.

Career Development Models: A Brief Overview of Relevant Theory

DTIC Science & Technology

1989-01-01

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

The Integration of Study and Work-Integrated Learning Experience through the Sequential, Embedded Completion of Tertiary Qualifications

ERIC Educational Resources Information Center

Whannell, Patricia; Humphries, Judy; Whannell, Robert; Usher, Kim

2015-01-01

A number of different models have been developed to integrate both Vocational Education and Training (VET) and university study with a view to producing work-ready graduates. This paper describes one joint initiative which allows students to integrate their theoretical study and work-integrated learning (WIL) experience by supporting a sequential,…

The Construct Validity of Attitudes toward Career Counseling Scale for Korean College Students

ERIC Educational Resources Information Center

Nam, Suk Kyung; In Park, Hyung

2015-01-01

This study aimed to examine the construct validity of the Attitudes Toward Career Counseling Scale (ATCCS) in Korea. In Study 1, confirmatory factor analysis (CFA) was used for testing the factor structure of the scale. The results supported a two-factor (value and stigma) model, which was theoretically driven from the original study. Results of…

A Novel Phased-Concept Course for the Delivery of Anatomy and Orthopedics Training in Medical Education

ERIC Educational Resources Information Center

Klima, Stefan; Hepp, Pierre; Löffler, Sabine; Cornwall, Jon; Hammer, Niels

2017-01-01

Integration of anatomy and clinical teaching is a theoretical ideal, yet there is a worldwide paucity of such amalgamation. These teaching models provide support for medical trainees, an important element in Germany where orthopedic intern numbers have declined and anecdotal evidence suggests disinterest in orthopedics. The aim of the study was to…

The Role of Cognition, Motivation, and Emotion in Explaining the Mathematics Achievement Gap between Hispanic and White Students

ERIC Educational Resources Information Center

Stevens, Tara; Olivarez, Arturo, Jr.; Hamman, Doug

2006-01-01

The authors investigated the relationships between cognitive, motivational, and emotional variables across Hispanic and White students to predict mathematics performance. A theoretically based structural model fit a total sample of 666 4th- to 10th-grade students well, supporting that self-efficacy, sources of self-efficacy, and emotional feedback…

Promoting Teachers' Social and Emotional Competence: A Replication Study of the Cultivating Awareness and Resilience in Education (CARE) Program

ERIC Educational Resources Information Center

Jennings, Patricia A.; Brown, Joshua L.; Frank, Jennifer; Tanler, Regin; Doyle, Sebrina; Rasheed, Damira; DeWeese, Anna; Greenberg, Mark

2014-01-01

The present study, which takes place in a high-poverty section of a large urban area of the northeastern United States, is based upon the prosocial classroom theoretical model that emphasizes the significance of teachers' social and emotional competence (SEC) and well-being in the development and maintenance of supportive teacher-student…

Recent statistical methods for orientation data

NASA Technical Reports Server (NTRS)

Batschelet, E.

1972-01-01

The application of statistical methods for determining the areas of animal orientation and navigation are discussed. The method employed is limited to the two-dimensional case. Various tests for determining the validity of the statistical analysis are presented. Mathematical models are included to support the theoretical considerations and tables of data are developed to show the value of information obtained by statistical analysis.

The Syntax and Semantics of ERICA. Technical Report No. 185, Psychology and Education Series.

ERIC Educational Resources Information Center

Smith, Robert Lawrence, Jr.

This report is a detailed empirical examination of Suppes' ideas about the syntax and semantics of natural language, and an attempt at supporting the proposal that model-theoretic semantics of the type first proposed by Tarski is a useful tool for understanding the semantics of natural language. Child speech was selected as the best place to find…

Systems in the Foundations of Information Systems Course to Retain Students and to Support the IS 2010 Model Curricula

ERIC Educational Resources Information Center

Slauson, Gayla Jo; Carpenter, Donald; Snyder, Johnny

2011-01-01

Systems in the Foundations of Information Systems course can be used to connect with students in computer information systems programs; a systematic approach to beginning student relationship management in this course is helpful. The authors suggest that four systems be created in the Foundations Course. These theoretical systems include an…

Rotordynamic Instability Problems in High-Performance Turbomachinery, 1988

NASA Technical Reports Server (NTRS)

1989-01-01

The continuing trend toward a unified view is supported with several developments in the design and manufacture of turbomachines with enhanced stability characteristics along with data and associated numerical/theoretical results. The intent is to provide a continuing impetus for an understanding and resolution of these problems. Topics addressed include: field experience, dampers, seals, impeller forces, bearings, and compressor and rotor modeling.

Imitation dynamics of vaccine decision-making behaviours based on the game theory.

PubMed

Yang, Junyuan; Martcheva, Maia; Chen, Yuming

2016-01-01

Based on game theory, we propose an age-structured model to investigate the imitation dynamics of vaccine uptake. We first obtain the existence and local stability of equilibria. We show that Hopf bifurcation can occur. We also establish the global stability of the boundary equilibria and persistence of the disease. The theoretical results are supported by numerical simulations.

The Impact of Federal Aid to States on Financial Support for the Public Schools.

ERIC Educational Resources Information Center

Barro, Stephen M.

This paper examines the fiscal impacts on public schools of some of the federal aid proposals under consideration by Congress. The four major discussion sections focus on (1) an outline of the overall analytic framework, including a conceptual model of federal, State, and local relationships; (2) a brief presentation of the theoretical analysis on…

Resilience Factors Associated with Adaptation in Families with Deaf or Hard of Hearing Children

ERIC Educational Resources Information Center

Ahlert, Ingrid A.; Greeff, Abraham P.

2012-01-01

The study objective was to identify and explore resilience qualities that help protect and support families facing the adversity associated with having a child with hearing loss. The Resiliency Model of Family Stress, Adjustment, and Adaptation (M. A. McCubbin & H. I. McCubbin, 1993, 1996) provided the study's theoretical framework. The 54…

Learning Outside of Classroom: Exploring the Active Part of an Informal Online English Learning Community in China

ERIC Educational Resources Information Center

Sun, Yanyan; Franklin, Teresa; Gao, Fei

2017-01-01

This study explored how the GRE Analytical Writing Section Discussion Forum, an informal online language learning community in China, functioned to support its members to improve their English writing proficiency. The Community of Inquiry (CoI) model was used as the theoretical framework to explore the existence of teaching presence, cognitive…

Family-supportive work environments and psychological strain: a longitudinal test of two theories.

PubMed

Odle-Dusseau, Heather N; Herleman, Hailey A; Britt, Thomas W; Moore, Dewayne D; Castro, Carl A; McGurk, Dennis

2013-01-01

Based on the Job Demands-Resources (JDR) model (E. Demerouti, A. B. Bakker, F. Nachreiner, & W. B. Schaufeli, 2001, The job demands-resources model of burnout. Journal of Applied Psychology, 86, 499-512) and Conservation of Resources (COR) theory (S. E. Hobfoll, 2002, Social and psychological resources and adaptation. Review of General Psychology, 6, 307-324), we tested three competing models that predict different directions of causation for relationships over time between family-supportive work environments (FSWE) and psychological strain, with two waves of data from a military sample. Results revealed support for both the JDR and COR theories, first in the static model where FSWE at Time 1 predicted psychological strain at Time 2 and when testing the opposite direction, where psychological strain at Time 1 predicted FSWE at Time 2. For change models, FSWE predicted changes in psychological strain across time, although the reverse causation model was not supported (psychological strain at Time 1 did not predict changes in FSWE). Also, changes in FSWE across time predicted psychological strain at Time 2, whereas changes in psychological strain did not predict FSWE at Time 2. Theoretically, these results are important for the work-family interface in that they demonstrate the application of a systems approach to studying work and family interactions, as support was obtained for both the JDR model with perceptions of FSWE predicting psychological strain (in both the static and change models), and for COR theory where psychological strain predicts FSWE across time.

Cognitive Attachment Model of Voices: Evidence Base and Future Implications

PubMed Central

Berry, Katherine; Varese, Filippo; Bucci, Sandra

2017-01-01

There is a robust association between hearing voices and exposure to traumatic events. Identifying mediating mechanisms for this relationship is key to theories of voice hearing and the development of therapies for distressing voices. This paper outlines the Cognitive Attachment model of Voices (CAV), a theoretical model to understand the relationship between earlier interpersonal trauma and distressing voice hearing. The model builds on attachment theory and well-established cognitive models of voices and argues that attachment and dissociative processes are key psychological mechanisms that explain how trauma influences voice hearing. Following the presentation of the model, the paper will review the current state of evidence regarding the proposed mechanisms of vulnerability to voice hearing and maintenance of voice-related distress. This review will include evidence from studies supporting associations between dissociation and voices, followed by details of our own research supporting the role of dissociation in mediating the relationship between trauma and voices and evidence supporting the role of adult attachment in influencing beliefs and relationships that voice hearers can develop with voices. The paper concludes by outlining the key questions that future research needs to address to fully test the model and the clinical implications that arise from the work. PMID:28713292

Stoichiometry constrains microbial response to root exudation - insights from a model and a field experiment in a temperate forest

NASA Astrophysics Data System (ADS)

Drake, J. E.; Darby, B. A.; Giasson, M.-A.; Kramer, M. A.; Phillips, R. P.; Finzi, A. C.

2012-06-01

Healthy plant roots release a wide range of chemicals into soils. This process, termed root exudation, is thought to increase the activity of microbes and the exo-enzymes they synthesize, leading to accelerated rates of carbon (C) mineralization and nutrient cycling in rhizosphere soils relative to bulk soils. The causal role of exudation, however, is difficult to isolate with in-situ observations, given the complex nature of the rhizosphere environment. We investigated the potential effects of root exudation on microbial and exo-enzyme activity using a theoretical model of decomposition and a field experiment, with a specific focus on the stoichiometric constraint of nitrogen (N) availability. The field experiment isolated the effect of exudation by pumping solutions of exudate mimics through microlysimeter "root simulators" into intact forest soils over two 50-day periods. Using a combined model-experiment approach, we tested two hypotheses: (1) exudation alone is sufficient to stimulate microbial and exo-enzyme activity in rhizosphere soils, and (2) microbial response to C-exudates (carbohydrates and organic acids) is constrained by N-limitation. Experimental delivery of exudate mimics containing C and N significantly increased microbial respiration, microbial biomass, and the activity of exo-enzymes that decompose labile components of soil organic matter (SOM, e.g., cellulose, amino sugars), while decreasing the activity of exo-enzymes that degrade recalcitrant SOM (e.g., polyphenols, lignin). However, delivery of C-only exudates had no effect on microbial biomass or overall exo-enzyme activity, and only increased microbial respiration. The theoretical decomposition model produced complementary results; the modeled microbial response to C-only exudates was constrained by limited N supply to support the synthesis of N-rich microbial biomass and exo-enzymes, while exuding C and N together elicited an increase in modeled microbial biomass, exo-enzyme activity, and decomposition. Thus, hypothesis (2) was supported, while hypothesis (1) was only supported when C and N compounds were exuded together. This study supports a cause-and-effect relationship between root exudation and enhanced microbial activity, and suggests that exudate stoichiometry is an important and underappreciated driver of microbial activity in rhizosphere soils.

Web-Based Virtual Patients in Nursing Education: Development and Validation of Theory-Anchored Design and Activity Models

PubMed Central

2014-01-01

Background Research has shown that nursing students find it difficult to translate and apply their theoretical knowledge in a clinical context. Virtual patients (VPs) have been proposed as a learning activity that can support nursing students in their learning of scientific knowledge and help them integrate theory and practice. Although VPs are increasingly used in health care education, they still lack a systematic consistency that would allow their reuse outside of their original context. There is therefore a need to develop a model for the development and implementation of VPs in nursing education. Objective The aim of this study was to develop and evaluate a virtual patient model optimized to the learning and assessment needs in nursing education. Methods The process of modeling started by reviewing theoretical frameworks reported in the literature and used by practitioners when designing learning and assessment activities. The Outcome-Present State Test (OPT) model was chosen as the theoretical framework. The model was then, in an iterative manner, developed and optimized to the affordances of virtual patients. Content validation was performed with faculty both in terms of the relevance of the chosen theories but also its applicability in nursing education. The virtual patient nursing model was then instantiated in two VPs. The students’ perceived usefulness of the VPs was investigated using a questionnaire. The result was analyzed using descriptive statistics. Results A virtual patient Nursing Design Model (vpNDM) composed of three layers was developed. Layer 1 contains the patient story and ways of interacting with the data, Layer 2 includes aspects of the iterative process of clinical reasoning, and finally Layer 3 includes measurable outcomes. A virtual patient Nursing Activity Model (vpNAM) was also developed as a guide when creating VP-centric learning activities. The students perceived the global linear VPs as a relevant learning activity for the integration of theory and practice. Conclusions Virtual patients that are adapted to the nursing paradigm can support nursing students’ development of clinical reasoning skills. The proposed virtual patient nursing design and activity models will allow the systematic development of different types of virtual patients from a common model and thereby create opportunities for sharing pedagogical designs across technical solutions. PMID:24727709

Enhanced Co-Worker Social Support in Isolated Work Groups and Its Mitigating Role on the Work-Family Conflict-Depression Loss Spiral.

PubMed

McTernan, Wesley P; Dollard, Maureen F; Tuckey, Michelle R; Vandenberg, Robert J

2016-03-29

This paper examines a loss spiral model (i.e., reciprocal relationships) between work-family conflict and depression, moderated by co-worker support. We expected that the moderation effect due to co-worker support would be evident among those working in isolation (i.e., mining workers) due to a greater level of intragroup attraction and saliency attributable to the proximity effects. We used a two wave panel study and data from a random population sample of Australian employees (n = 2793, [n = 112 mining, n = 2681 non-mining]). Using structural equation modelling we tested the reciprocal three way interaction effects. In line with our theory, co-worker support buffered the reciprocal relationship between WFC and depression, showing a protective effect in both pathways. These moderation effects were found in the mining industry only suggesting a proximity component moderates the social support buffer hypothesis (i.e., a three way interaction effect). The present paper integrates previous theoretical perspectives of stress and support, and provides insight into the changing dynamics of workplace relationships.

Enhanced Co-Worker Social Support in Isolated Work Groups and Its Mitigating Role on the Work-Family Conflict-Depression Loss Spiral

PubMed Central

McTernan, Wesley P.; Dollard, Maureen F.; Tuckey, Michelle R.; Vandenberg, Robert J.

2016-01-01

This paper examines a loss spiral model (i.e., reciprocal relationships) between work-family conflict and depression, moderated by co-worker support. We expected that the moderation effect due to co-worker support would be evident among those working in isolation (i.e., mining workers) due to a greater level of intragroup attraction and saliency attributable to the proximity effects. We used a two wave panel study and data from a random population sample of Australian employees (n = 2793, [n = 112 mining, n = 2681 non-mining]). Using structural equation modelling we tested the reciprocal three way interaction effects. In line with our theory, co-worker support buffered the reciprocal relationship between WFC and depression, showing a protective effect in both pathways. These moderation effects were found in the mining industry only suggesting a proximity component moderates the social support buffer hypothesis (i.e., a three way interaction effect). The present paper integrates previous theoretical perspectives of stress and support, and provides insight into the changing dynamics of workplace relationships. PMID:27043592

Annual Research Briefs - 2000: Center for Turbulence Research

NASA Technical Reports Server (NTRS)

2000-01-01

This report contains the 2000 annual progress reports of the postdoctoral Fellows and visiting scholars of the Center for Turbulence Research (CTR). It summarizes the research efforts undertaken under the core CTR program. Last year, CTR sponsored sixteen resident Postdoctoral Fellows, nine Research Associates, and two Senior Research Fellows, hosted seven short term visitors, and supported four doctoral students. The Research Associates are supported by the Departments of Defense and Energy. The reports in this volume are divided into five groups. The first group largely consists of the new areas of interest at CTR. It includes efficient algorithms for molecular dynamics, stability in protoplanetary disks, and experimental and numerical applications of evolutionary optimization algorithms for jet flow control. The next group of reports is in experimental, theoretical, and numerical modeling efforts in turbulent combustion. As more challenging computations are attempted, the need for additional theoretical and experimental studies in combustion has emerged. A pacing item for computation of nonpremixed combustion is the prediction of extinction and re-ignition phenomena, which is currently being addressed at CTR. The third group of reports is in the development of accurate and efficient numerical methods, which has always been an important part of CTR's work. This is the tool development part of the program which supports our high fidelity numerical simulations in such areas as turbulence in complex geometries, hypersonics, and acoustics. The final two groups of reports are concerned with LES and RANS prediction methods. There has been significant progress in wall modeling for LES of high Reynolds number turbulence and in validation of the v(exp 2) - f model for industrial applications.

A Phenomenlogical Model of Durotaxis

NASA Astrophysics Data System (ADS)

Yu, Guangyuan; Feng, Jingchen; Levine, Herbert; CenterTheoretical Biological Physics Collaboration

Cells exhibit qualitatively different behaviors on substrates with different rigidities. The fact that cells are more polarized on the stiffer substrate motivates us to construct a two-dimensional cell with the distribution of focal adhesions dependent on substrate rigidities. Our model reproduces the experimental observation that the persistence time is higher on the stiffer substrate. We show that stiffness dependent polarization will lead to the so-called durotaxis, the preference in moving towards stiffer substrates. This propensity is then characterized by the durotactic index first defined in experiments. We also derive and validate the 2D corresponding Fokker-Planck equation associated with our model. Our model highlights the role of focal adhesion arrangement in durotaxis. It may be applied to manipulate the movement of cells for clinical purposes. This work was supported by the National Science Foundation Center for Theoretical Biological Physics (Grant NSF PHY-1427654). HL was also supported by the CPRIT Scholar program of the State of Texas.

Peer-to-peer communication, cancer prevention, and the internet

PubMed Central

Ancker, Jessica S.; Carpenter, Kristen M.; Greene, Paul; Hoffmann, Randi; Kukafka, Rita; Marlow, Laura A.V.; Prigerson, Holly G.; Quillin, John M.

2013-01-01

Online communication among patients and consumers through support groups, discussion boards, and knowledge resources is becoming more common. In this paper, we discuss key methods through which such web-based peer-to-peer communication may affect health promotion and disease prevention behavior (exchanges of information, emotional and instrumental support, and establishment of group norms and models). We also discuss several theoretical models for studying online peer communication, including social theory, health communication models, and health behavior models. Although online peer communication about health and disease is very common, research evaluating effects on health behaviors, mediators, and outcomes is still relatively sparse. We suggest that future research in this field should include formative evaluation and studies of effects on mediators of behavior change, behaviors, and outcomes. It will also be important to examine spontaneously emerging peer communication efforts to see how they can be integrated with theory-based efforts initiated by researchers. PMID:19449267

Translation of Contextual Control Model to chronic disease management: A paradigm to guide design of cognitive support systems.

PubMed

Leecaster, Molly K; Weir, Charlene R; Drews, Frank A; Hellewell, James L; Bolton, Daniel; Jones, Makoto M; Nebeker, Jonathan R

2017-07-01

Electronic health records (EHRs) continue to be criticized for providing poor cognitive support. Defining cognitive support has lacked theoretical foundation. We developed a measurement model of cognitive support based on the Contextual Control Model (COCOM), which describes control characteristics of an "orderly" joint system and proposes 4 levels of control: scrambled, opportunistic, tactical, and strategic. 35 clinicians (5 centers) were interviewed pre and post outpatient clinical visits and audiotaped during the visit. Behaviors pertaining to hypertension management were systematically mapped to the COCOM control characteristics of: (1) time horizon, (2) uncertainty assessment, (3) consideration of multiple goals, (4) causal model described, and (5) explicitness of plan. Each encounter was classified for overall mode of control. Visits with deviation versus no deviation from hypertension goals were compared. Reviewer agreement was high. Control characteristics differed significantly between deviation groups (Wilcox rank sum p<.01). K-means cluster analysis of control characteristics, stratified by deviation were distinct, with higher goal deviations associated with more control characteristics. The COCOM control characteristics appear to be areas of potential yield for improved user-experience design. Published by Elsevier Inc.

Oklahoma Center for High Energy Physics (OCHEP)

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

Nandi, S; Strauss, M J; Snow, J

2012-02-29

The DOE EPSCoR implementation grant, with the support from the State of Oklahoma and from the three universities, Oklahoma State University, University of Oklahoma and Langston University, resulted in establishing of the Oklahoma Center for High Energy Physics (OCHEP) in 2004. Currently, OCHEP continues to flourish as a vibrant hub for research in experimental and theoretical particle physics and an educational center in the State of Oklahoma. All goals of the original proposal were successfully accomplished. These include foun- dation of a new experimental particle physics group at OSU, the establishment of a Tier 2 computing facility for the Largemore » Hadron Collider (LHC) and Tevatron data analysis at OU and organization of a vital particle physics research center in Oklahoma based on resources of the three universities. OSU has hired two tenure-track faculty members with initial support from the grant funds. Now both positions are supported through OSU budget. This new HEP Experimental Group at OSU has established itself as a full member of the Fermilab D0 Collaboration and LHC ATLAS Experiment and has secured external funds from the DOE and the NSF. These funds currently support 2 graduate students, 1 postdoctoral fellow, and 1 part-time engineer. The grant initiated creation of a Tier 2 computing facility at OU as part of the Southwest Tier 2 facility, and a permanent Research Scientist was hired at OU to maintain and run the facility. Permanent support for this position has now been provided through the OU university budget. OCHEP represents a successful model of cooperation of several universities, providing the establishment of critical mass of manpower, computing and hardware resources. This led to increasing Oklahoma's impact in all areas of HEP, theory, experiment, and computation. The Center personnel are involved in cutting edge research in experimental, theoretical, and computational aspects of High Energy Physics with the research areas ranging from the search for new phenomena at the Fermilab Tevatron and the CERN Large Hadron Collider to theoretical modeling, computer simulation, detector development and testing, and physics analysis. OCHEP faculty members participating on the D0 collaboration at the Fermilab Tevatron and on the ATLAS collaboration at the CERN LHC have made major impact on the Standard Model (SM) Higgs boson search, top quark studies, B physics studies, and measurements of Quantum Chromodynamics (QCD) phenomena. The OCHEP Grid computing facility consists of a large computer cluster which is playing a major role in data analysis and Monte Carlo productions for both the D0 and ATLAS experiments. Theoretical efforts are devoted to new ideas in Higgs bosons physics, extra dimensions, neutrino masses and oscillations, Grand Unified Theories, supersymmetric models, dark matter, and nonperturbative quantum field theory. Theory members are making major contributions to the understanding of phenomena being explored at the Tevatron and the LHC. They have proposed new models for Higgs bosons, and have suggested new signals for extra dimensions, and for the search of supersymmetric particles. During the seven year period when OCHEP was partially funded through the DOE EPSCoR implementation grant, OCHEP members published over 500 refereed journal articles and made over 200 invited presentations at major conferences. The Center is also involved in education and outreach activities by offering summer research programs for high school teachers and college students, and organizing summer workshops for high school teachers, sometimes coordinating with the Quarknet programs at OSU and OU. The details of the Center can be found in http://ochep.phy.okstate.edu.« less

Choosing where to work at work - towards a theoretical model of benefits and risks of activity-based flexible offices.

PubMed

Wohlers, Christina; Hertel, Guido

2017-04-01

Although there is a trend in today's organisations to implement activity-based flexible offices (A-FOs), only a few studies examine consequences of this new office type. Moreover, the underlying mechanisms why A-FOs might lead to different consequences as compared to cellular and open-plan offices are still unclear. This paper introduces a theoretical framework explaining benefits and risks of A-FOs based on theories from work and organisational psychology. After deriving working conditions specific for A-FOs (territoriality, autonomy, privacy, proximity and visibility), differences in working conditions between A-FOs and alternative office types are proposed. Further, we suggest how these differences in working conditions might affect work-related consequences such as well-being, satisfaction, motivation and performance on the individual, the team and the organisational level. Finally, we consider task-related (e.g. task variety), person-related (e.g. personality) and organisational (e.g. leadership) moderators. Based on this model, future research directions as well as practical implications are discussed. Practitioner Summary: Activity-based flexible offices (A-FOs) are popular in today's organisations. This article presents a theoretical model explaining why and when working in an A-FO evokes benefits and risks for individuals, teams and organisations. According to the model, A-FOs are beneficial when management encourages employees to use the environment appropriately and supports teams.

Processes of Internal and International Migration from Chitwan, Nepal.

PubMed

Bohra, Pratikshya; Massey, Douglas S

2009-01-01

In this study we examine which factors predict internal and international migration from Chitwan, a flat valley located in the South-Central region of Nepal, seeking to measure the effect of theoretically specified variables such as human capital, social capital, physical capital, and neighborhood socioeconomic conditions while controlling for demographic variables. We use data from the Chitwan Valley Family Study (CVFS) to estimate a series of discrete time event history models of first and repeat migration to three competing destinations: other locations within Chitwan, other districts within Nepal, and places outside of Nepal. Results support hypotheses derived from neoclassical economics, the theory of new economics of migration, social capital theory, and cumulative causation theory. Our results underscore the need for a synthetic theoretical model that incorporates factors operating at the individual, household, and community levels. The use of multiple explanatory models yields a clearer picture of the forces driving internal and international migration from rural districts in developing nations such as Nepal.

Processes of Internal and International Migration from Chitwan, Nepal

PubMed Central

Bohra, Pratikshya; Massey, Douglas S.

2011-01-01

In this study we examine which factors predict internal and international migration from Chitwan, a flat valley located in the South-Central region of Nepal, seeking to measure the effect of theoretically specified variables such as human capital, social capital, physical capital, and neighborhood socioeconomic conditions while controlling for demographic variables. We use data from the Chitwan Valley Family Study (CVFS) to estimate a series of discrete time event history models of first and repeat migration to three competing destinations: other locations within Chitwan, other districts within Nepal, and places outside of Nepal. Results support hypotheses derived from neoclassical economics, the theory of new economics of migration, social capital theory, and cumulative causation theory. Our results underscore the need for a synthetic theoretical model that incorporates factors operating at the individual, household, and community levels. The use of multiple explanatory models yields a clearer picture of the forces driving internal and international migration from rural districts in developing nations such as Nepal. PMID:21423821

Gust wind tunnel study on ballast pick-up by high-speed trains

NASA Astrophysics Data System (ADS)

Navarro-Medina, F.; Sanz-Andres, A.; Perez-Grande, I.

2012-01-01

This paper describes the experimental setup, procedure, and results obtained, concerning the dynamics of a body lying on a floor, attached to a hinge, and exposed to an unsteady flow, which is a model of the initiation of rotational motion of ballast stones due to the wind generated by the passing of a high-speed train. The idea is to obtain experimental data to support the theoretical model developed in Sanz-Andres and Navarro-Medina (J Wind Eng Ind Aerodyn 98, 772-783, (2010), aimed at analyzing the initial phase of the ballast train-induced-wind erosion (BATIWE) phenomenon. The experimental setup is based on an open circuit, closed test section, low-speed wind tunnel, with a new sinusoidal gust generator mechanism concept, designed and built at the IDR/UPM. The tunnel's main characteristic is the ability to generate a flow with a uniform velocity profile and sinusoidal time fluctuation of the speed. Experimental results and theoretical model predictions are in good agreement.

The neural representation of unexpected uncertainty during value-based decision making.

PubMed

Payzan-LeNestour, Elise; Dunne, Simon; Bossaerts, Peter; O'Doherty, John P

2013-07-10

Uncertainty is an inherent property of the environment and a central feature of models of decision-making and learning. Theoretical propositions suggest that one form, unexpected uncertainty, may be used to rapidly adapt to changes in the environment, while being influenced by two other forms: risk and estimation uncertainty. While previous studies have reported neural representations of estimation uncertainty and risk, relatively little is known about unexpected uncertainty. Here, participants performed a decision-making task while undergoing functional magnetic resonance imaging (fMRI), which, in combination with a Bayesian model-based analysis, enabled us to separately examine each form of uncertainty examined. We found representations of unexpected uncertainty in multiple cortical areas, as well as the noradrenergic brainstem nucleus locus coeruleus. Other unique cortical regions were found to encode risk, estimation uncertainty, and learning rate. Collectively, these findings support theoretical models in which several formally separable uncertainty computations determine the speed of learning. Copyright © 2013 Elsevier Inc. All rights reserved.

Impact of Competing Values and Choices on Democratic Support in Hong Kong.

PubMed

Lam, Wai-Man

2013-08-01

This paper examines the reasons for the relatively low democratic support (DS) in Hong Kong in the context of competing values and choices based on the previous Asian Barometer Surveys. In so doing, it establishes a three-factor theoretical model that includes survey attitudinal statements related to authoritarianism (AU), nationalism (NA) and economic evaluations (EC) on DS. Using confirmatory factor analysis (CFA), the analysis shows that the hypothesized model is a very good fit. The Hong Kong people's relatively low DS, in terms of their unconditional support for democracy and the degree of democracy they want for Hong Kong, can be well explained by the three factors in combination. The factors have various extent of impact on DS, with AU being the strongest, followed by EC, and then NA. The paper contributes by illustrating the usefulness of CFA in political values research, unraveling the comparative importance of the values and choices in affecting DS, and establishing a model for further testing.

The FoReVer Methodology: A MBSE Framework for Formal Verification

NASA Astrophysics Data System (ADS)

Baracchi, Laura; Mazzini, Silvia; Cimatti, Alessandro; Tonetta, Stefano; Garcia, Gerald

2013-08-01

The need for high level of confidence and operational integrity in critical space (software) systems is well recognized in the Space industry and has been addressed so far through rigorous System and Software Development Processes and stringent Verification and Validation regimes. The Model Based Space System Engineering process (MBSSE) derived in the System and Software Functional Requirement Techniques study (SSFRT) focused on the application of model based engineering technologies to support the space system and software development processes, from mission level requirements to software implementation through model refinements and translations. In this paper we report on our work in the ESA-funded FoReVer project where we aim at developing methodological, theoretical and technological support for a systematic approach to the space avionics system development, in phases 0/A/B/C. FoReVer enriches the MBSSE process with contract-based formal verification of properties, at different stages from system to software, through a step-wise refinement approach, with the support for a Software Reference Architecture.

Recent theoretical, neural, and clinical advances in sustained attention research.

PubMed

Fortenbaugh, Francesca C; DeGutis, Joseph; Esterman, Michael

2017-05-01

Models of attention often distinguish among attention subtypes, with classic models separating orienting, switching, and sustaining functions. Compared with other forms of attention, the neurophysiological basis of sustaining attention has received far less notice, yet it is known that momentary failures of sustained attention can have far-ranging negative effects in healthy individuals, and lasting sustained attention deficits are pervasive in clinical populations. In recent years, however, there has been increased interest in characterizing moment-to-moment fluctuations in sustained attention, in addition to the overall vigilance decrement, and understanding how these neurocognitive systems change over the life span and across various clinical populations. The use of novel neuroimaging paradigms and statistical approaches has allowed for better characterization of the neural networks supporting sustained attention and has highlighted dynamic interactions within and across multiple distributed networks that predict behavioral performance. These advances have also provided potential biomarkers to identify individuals with sustained attention deficits. These findings have led to new theoretical models explaining why sustaining focused attention is a challenge for individuals and form the basis for the next generation of sustained attention research, which seeks to accurately diagnose and develop theoretically driven treatments for sustained attention deficits that affect a variety of clinical populations. © 2017 New York Academy of Sciences.

Direct observation of surface-state thermal oscillations in SmB6 oscillators

NASA Astrophysics Data System (ADS)

Casas, Brian; Stern, Alex; Efimkin, Dmitry K.; Fisk, Zachary; Xia, Jing

2018-01-01

SmB6 is a mixed valence Kondo insulator that exhibits a sharp increase in resistance following an activated behavior that levels off and saturates below 4 K. This behavior can be explained by the proposal of SmB6 representing a new state of matter, a topological Kondo insulator, in which a Kondo gap is developed, and topologically protected surface conduction dominates low-temperature transport. Exploiting its nonlinear dynamics, a tunable SmB6 oscillator device was recently demonstrated, where a small dc current generates large oscillating voltages at frequencies from a few Hz to hundreds of MHz. This behavior was explained by a theoretical model describing the thermal and electronic dynamics of coupled surface and bulk states. However, a crucial aspect of this model, the predicted temperature oscillation in the surface state, has not been experimentally observed to date. This is largely due to the technical difficulty of detecting an oscillating temperature of the very thin surface state. Here we report direct measurements of the time-dependent surface-state temperature in SmB6 with a RuO2 microthermometer. Our results agree quantitatively with the theoretically simulated temperature waveform, and hence support the validity of the oscillator model, which will provide accurate theoretical guidance for developing future SmB6 oscillators at higher frequencies.

Evolution of spatially structured host-parasite interactions.

PubMed

Lion, S; Gandon, S

2015-01-01

Spatial structure has dramatic effects on the demography and the evolution of species. A large variety of theoretical models have attempted to understand how local dispersal may shape the coevolution of interacting species such as host-parasite interactions. The lack of a unifying framework is a serious impediment for anyone willing to understand current theory. Here, we review previous theoretical studies in the light of a single epidemiological model that allows us to explore the effects of both host and parasite migration rates on the evolution and coevolution of various life-history traits. We discuss the impact of local dispersal on parasite virulence, various host defence strategies and local adaptation. Our analysis shows that evolutionary and coevolutionary outcomes crucially depend on the details of the host-parasite life cycle and on which life-history trait is involved in the interaction. We also discuss experimental studies that support the effects of spatial structure on the evolution of host-parasite interactions. This review highlights major similarities between some theoretical results, but it also reveals an important gap between evolutionary and coevolutionary models. We discuss possible ways to bridge this gap within a more unified framework that would reconcile spatial epidemiology, evolution and coevolution. © 2014 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

Grassland Production Change Due Comparison of NPP Estimates by Theoretical Model and Satellite Data from MODIS

NASA Astrophysics Data System (ADS)

Campbell, E. E.; Oliveira, J. D. C.; Lamparelli, R.; Soares, J.; Monteiro, L. A.; Jaiswal, D.; Sheehan, J. J.; Figueiredo, G. K. D. A.; Lynd, L. R.

2017-12-01

Accessing the changes in net primary production (NPP) from grassland in the globe has important applications, e.g. can identify where land have been degraded or in opposite site have been intensified. The aim of this study is to identify the changes occurred in grassland production due management practices and climate change. A recent comparison between a theoretical model of aboveground NPP and satellite data will be performed for the years 2000 to 2003. The theoretical model links NPP to climate, defined as total annual rainfall. Satellite data will use the total annual NPP from MODIS sensor (MOD17A3), that each pixel (spatial resolution of 1 km) include biome type information, daily meteorological data and the fraction absorbed of photosynthetic active radiation (FPAR) and leaf area index (LAI). Both NPP results were set in pastureland that is occupied by ruminants based on year 2000. The correlation between total NPP's values on year 2000 was 0.77. Therefore, the change in the differences between these models can reflect management practices and climate change impacts on grassland biomass production and also the reasonability of using both databases for predicting yield gap. The different from both NPP estimates will be then classified in three groups: no significant difference, significant increase and significant decrease. The outcome results will show the fluctuations in biomass from grassland worldwide. The regions with ongoing pasture degradation will be indentified, and can suggest a need for improvement. In the other hand, pastureland with significant increase in biomass will offer an example of intensification potential. The tendency of the pastureland in each region can give a support for policy makers in order to achieve a sustainability use of the land. Financial Support: FAPESP process 2017/06037-4, 2016/08741-8, 2017/08970-0, 2016/08742-4 and 2014/26767-9

Patients’ Acceptance of Smartphone Health Technology for Chronic Disease Management: A Theoretical Model and Empirical Test

PubMed Central

Dou, Kaili; Yu, Ping; Liu, Fang; Guan, YingPing; Li, Zhenye; Ji, Yumeng; Du, Ningkai; Lu, Xudong; Duan, Huilong

2017-01-01

Background Chronic disease patients often face multiple challenges from difficult comorbidities. Smartphone health technology can be used to help them manage their conditions only if they accept and use the technology. Objective The aim of this study was to develop and test a theoretical model to predict and explain the factors influencing patients’ acceptance of smartphone health technology for chronic disease management. Methods Multiple theories and factors that may influence patients’ acceptance of smartphone health technology have been reviewed. A hybrid theoretical model was built based on the technology acceptance model, dual-factor model, health belief model, and the factors identified from interviews that might influence patients’ acceptance of smartphone health technology for chronic disease management. Data were collected from patient questionnaire surveys and computer log records about 157 hypertensive patients’ actual use of a smartphone health app. The partial least square method was used to test the theoretical model. Results The model accounted for .412 of the variance in patients’ intention to adopt the smartphone health technology. Intention to use accounted for .111 of the variance in actual use and had a significant weak relationship with the latter. Perceived ease of use was affected by patients’ smartphone usage experience, relationship with doctor, and self-efficacy. Although without a significant effect on intention to use, perceived ease of use had a significant positive influence on perceived usefulness. Relationship with doctor and perceived health threat had significant positive effects on perceived usefulness, countering the negative influence of resistance to change. Perceived usefulness, perceived health threat, and resistance to change significantly predicted patients’ intentions to use the technology. Age and gender had no significant influence on patients’ acceptance of smartphone technology. The study also confirmed the positive relationship between intention to use and actual use of smartphone health apps for chronic disease management. Conclusions This study developed a theoretical model to predict patients’ acceptance of smartphone health technology for chronic disease management. Although resistance to change is a significant barrier to technology acceptance, careful management of doctor-patient relationship, and raising patients’ awareness of the negative effect of chronic disease can negate the effect of resistance and encourage acceptance and use of smartphone health technology to support chronic disease management for patients in the community. PMID:29212629

A PetriNet-Based Approach for Supporting Traceability in Cyber-Physical Manufacturing Systems

PubMed Central

Huang, Jiwei; Zhu, Yeping; Cheng, Bo; Lin, Chuang; Chen, Junliang

2016-01-01

With the growing popularity of complex dynamic activities in manufacturing processes, traceability of the entire life of every product has drawn significant attention especially for food, clinical materials, and similar items. This paper studies the traceability issue in cyber-physical manufacturing systems from a theoretical viewpoint. Petri net models are generalized for formulating dynamic manufacturing processes, based on which a detailed approach for enabling traceability analysis is presented. Models as well as algorithms are carefully designed, which can trace back the lifecycle of a possibly contaminated item. A practical prototype system for supporting traceability is designed, and a real-life case study of a quality control system for bee products is presented to validate the effectiveness of the approach. PMID:26999141

A PetriNet-Based Approach for Supporting Traceability in Cyber-Physical Manufacturing Systems.

PubMed

Huang, Jiwei; Zhu, Yeping; Cheng, Bo; Lin, Chuang; Chen, Junliang

2016-03-17

With the growing popularity of complex dynamic activities in manufacturing processes, traceability of the entire life of every product has drawn significant attention especially for food, clinical materials, and similar items. This paper studies the traceability issue in cyber-physical manufacturing systems from a theoretical viewpoint. Petri net models are generalized for formulating dynamic manufacturing processes, based on which a detailed approach for enabling traceability analysis is presented. Models as well as algorithms are carefully designed, which can trace back the lifecycle of a possibly contaminated item. A practical prototype system for supporting traceability is designed, and a real-life case study of a quality control system for bee products is presented to validate the effectiveness of the approach.

Towards a model of contemporary parenting: the parenting behaviours and dimensions questionnaire.

PubMed

Reid, Carly A Y; Roberts, Lynne D; Roberts, Clare M; Piek, Jan P

2015-01-01

The assessment of parenting has been problematic due to theoretical disagreement, concerns over generalisability, and problems with the psychometric properties of current parenting measures. The aim of this study was to develop a comprehensive, psychometrically sound self-report parenting measure for use with parents of preadolescent children, and to use this empirical scale development process to identify the core dimensions of contemporary parenting behaviour. Following item generation and parent review, 846 parents completed an online survey comprising 116 parenting items. Exploratory and confirmatory factor analyses supported a six factor parenting model, comprising Emotional Warmth, Punitive Discipline, Anxious Intrusiveness, Autonomy Support, Permissive Discipline and Democratic Discipline. This measure will allow for the comprehensive and consistent assessment of parenting in future research and practice.

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

NASA Astrophysics Data System (ADS)

Mazilu, T.; Leu, M.

2017-08-01

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

Stereotypes Can “Get Under the Skin”: Testing a Self-Stereotyping and Psychological Resource Model of Overweight and Obesity

PubMed Central

Rivera, Luis M.; Paredez, Stefanie M.

2014-01-01

The authors draw upon social, personality, and health psychology to propose and test a self-stereotyping and psychological resource model of overweight and obesity. The model contends that self-stereotyping depletes psychological resources, namely self-esteem, that help to prevent overweight and obesity. In support of the model, mediation analysis demonstrates that adult Hispanics who highly self-stereotype had lower levels of self-esteem than those who self-stereotype less, which in turn predicted higher levels of body mass index (overweight and obesity levels). Furthermore, the model did not hold for the referent sample, White participants, and an alternative mediation model was not supported. These data are the first to theoretically and empirically link self-stereotyping and self-esteem (a psychological resource) with a strong physiological risk factor for morbidity and short life expectancy in stigmatized individuals. Thus, this research contributes to understanding ethnic-racial health disparities in the United States and beyond. PMID:25221353

Residential water demand model under block rate pricing: A case study of Beijing, China

NASA Astrophysics Data System (ADS)

Chen, H.; Yang, Z. F.

2009-05-01

In many cities, the inconsistency between water supply and water demand has become a critical problem because of deteriorating water shortage and increasing water demand. Uniform price of residential water cannot promote the efficient water allocation. In China, block water price will be put into practice in the future, but the outcome of such regulation measure is unpredictable without theory support. In this paper, the residential water is classified by the volume of water usage based on economic rules and block water is considered as different kinds of goods. A model based on extended linear expenditure system (ELES) is constructed to simulate the relationship between block water price and water demand, which provide theoretical support for the decision-makers. Finally, the proposed model is used to simulate residential water demand under block rate pricing in Beijing.

A new model in achieving Green Accounting at hotels in Bali

NASA Astrophysics Data System (ADS)

Astawa, I. P.; Ardina, C.; Yasa, I. M. S.; Parnata, I. K.

2018-01-01

The concept of green accounting becomes a debate in terms of its implementation in a company. The result of previous studies indicates that there are no standard model regarding its implementation to support performance. The research aims to create a different green accounting model to other models by using local cultural elements as the variables in building it. The research is conducted in two steps. The first step is designing the model based on theoretical studies by considering the main and supporting elements in building the concept of green accounting. The second step is conducting a model test at 60 five stars hotels started with data collection through questionnaire and followed by data processing using descriptive statistic. The result indicates that the hotels’ owner has implemented green accounting attributes and it supports previous studies. Another result, which is a new finding, shows that the presence of local culture, government regulation, and the awareness of hotels’ owner has important role in the development of green accounting concept. The results of the research give contribution to accounting science in terms of green reporting. The hotel management should adopt local culture in building the character of accountant hired in the accounting department.

Cost shifting revisited: the case of service intensity.

PubMed

Friesner, Daniel L; Rosenman, Robert

2002-02-01

This paper examines whether a health care provider's choice of service intensity for any patient group affects its cost shifting behavior. Our theoretical models indicate that firms may respond to lower prospective payment by decreasing service intensity to all of its patient groups, thereby giving firms an alternative to cost shifting. Additionally, the conditions under which cost shifting and lower service intensity occur are identical, regardless of profit status. Using a panel of California hospitals, we found that nonprofit hospitals do cost shift, while profit-maximizing hospitals do not. However, both firms respond to lower prospective payment by decreasing service intensity, thus supporting our theoretical conclusion that lower service intensity can be used as an alternative to cost shifting.

Formation of Virtual Organizations in Grids: A Game-Theoretic Approach

NASA Astrophysics Data System (ADS)

Carroll, Thomas E.; Grosu, Daniel

The execution of large scale grid applications requires the use of several computational resources owned by various Grid Service Providers (GSPs). GSPs must form Virtual Organizations (VOs) to be able to provide the composite resource to these applications. We consider grids as self-organizing systems composed of autonomous, self-interested GSPs that will organize themselves into VOs with every GSP having the objective of maximizing its profit. We formulate the resource composition among GSPs as a coalition formation problem and propose a game-theoretic framework based on cooperation structures to model it. Using this framework, we design a resource management system that supports the VO formation among GSPs in a grid computing system.

A Gendered Lifestyle-Routine Activity Approach to Explaining Stalking Victimization in Canada.

PubMed

Reyns, Bradford W; Henson, Billy; Fisher, Bonnie S; Fox, Kathleen A; Nobles, Matt R

2016-05-01

Research into stalking victimization has proliferated over the last two decades, but several research questions related to victimization risk remain unanswered. Accordingly, the present study utilized a lifestyle-routine activity theoretical perspective to identify risk factors for victimization. Gender-based theoretical models also were estimated to assess the possible moderating effects of gender on the relationship between lifestyle-routine activity concepts and victimization risk. Based on an analysis of a representative sample of more than 15,000 residents of Canada from the Canadian General Social Survey (GSS), results suggested conditional support for lifestyle-routine activity theory and for the hypothesis that predictors of stalking victimization may be gender based. © The Author(s) 2015.

Prediction of the amount of urban waste solids by applying a gray theoretical model.

PubMed

Li, Xiao-Ming; Zeng, Guang-Ming; Wang, Ming; Liu, Jin-Jin

2003-01-01

Urban waste solids are now becoming one of the most crucial environmental problems. There are several different kinds of technologies normally used for waste solids disposal, among which landfill is more favorable in China than others, especially for urban waste solids. Most of the design works up to now are based on a roughly estimation of the amount of urban waste solids without any theoretical support, which lead to a series problems. To meet the basic information requirements for the design work, the amount of the urban waste solids was predicted in this research by applying the gray theoretical model GM (1,1) through non-linear differential equation simulation. The model parameters were estimated with the least square method (LSM) by running a certain MATALAB program, and the hypothesis test results show that the residual between the prediction value and the actual value approximately comply with the normal distribution N (0, 0.21(2)), and the probability of the residual within the range ( -0.17, 0.19) is more than 95%, which indicate obviously that the model can be well used for the prediction of the amount of waste solids and those had been already testified by the latest two years data about the urban waste solids from Loudi City of China. With this model, the predicted amount of the waste solids produced in Loudi City in the next 30 years is 8049000 ton in total.

Theoretical analysis of Lumry-Eyring models in differential scanning calorimetry

PubMed Central

Sanchez-Ruiz, Jose M.

1992-01-01

A theoretical analysis of several protein denaturation models (Lumry-Eyring models) that include a rate-limited step leading to an irreversibly denatured state of the protein (the final state) has been carried out. The differential scanning calorimetry transitions predicted for these models can be broadly classified into four groups: situations A, B, C, and C′. (A) The transition is calorimetrically irreversible but the rate-limited, irreversible step takes place with significant rate only at temperatures slightly above those corresponding to the transition. Equilibrium thermodynamics analysis is permissible. (B) The transition is distorted by the occurrence of the rate-limited step; nevertheless, it contains thermodynamic information about the reversible unfolding of the protein, which could be obtained upon the appropriate data treatment. (C) The heat absorption is entirely determined by the kinetics of formation of the final state and no thermodynamic information can be extracted from the calorimetric transition; the rate-determining step is the irreversible process itself. (C′) same as C, but, in this case, the rate-determining step is a previous step in the unfolding pathway. It is shown that ligand and protein concentration effects on transitions corresponding to situation C (strongly rate-limited transitions) are similar to those predicted by equilibrium thermodynamics for simple reversible unfolding models. It has been widely held in recent literature that experimentally observed ligand and protein concentration effects support the applicability of equilibrium thermodynamics to irreversible protein denaturation. The theoretical analysis reported here disfavors this claim. PMID:19431826

From "They" Science to "Our" Science: Hip Hop Epistemology in STEAM Education

NASA Astrophysics Data System (ADS)

Dolberry, Maurice E.

Hip hop has moved from being considered a type of music into being understood as a culture in which a prominent type of music originates. Hip hop culture has a philosophy and epistemological constructs as well. This study analyzed those constructs to determine how conceptions of science factor in hip hop worldviews. Pedagogical models in culturally responsive teaching and Science, Technology, Engineering, Arts, and Mathematics (STEAM) education were also examined to discern their philosophical connections with hip hop culture. These connections were used to create two theoretical models. The first one, Hip Hop Science, described how scientific thought functions in hip hop culture. The second model, Hip Hop STEAM Pedagogy, proposes how hip hop culture can inform STEAM teaching practices. The study began by using Critical Race Theory to create a theoretical framework proposing how the two theoretical models could be derived from the philosophical and pedagogical concepts. Content analysis and narrative inquiry were used to analyze data collected from scholarly texts, hip hop songs, and interviews with hip hop-responsive educators. The data from these sources were used initially to assess the adequacy of the proposed theoretical framework, and subsequently to improve its viability. Four overlapping themes emerged from the data analyses, including hip hop-resistance to formal education; how hip hop culture informs pedagogical practice in hip hop-responsive classrooms; conceptions of knowledge and reality that shape how hip hoppers conduct scientific inquiry; and hip hop-based philosophies of effective teaching for hip hoppers as a marginalized cultural group. The findings indicate that there are unique connections between hip hop epistemology, sciencemindedness, and pedagogical practices in STEAM education. The revised theoretical framework clarified the nature of these connections, and supported claims from prior research that hip hop culture provides viable sites of engagement for STEAM educators. It concluded with suggestions for future research that further explicates hip hop epistemology and Hip Hop STEAM Pedagogy.

Misleading Theoretical Assumptions in Hypertext/Hypermedia Research.

ERIC Educational Resources Information Center

Tergan, Sigmar-Olaf

1997-01-01

Reviews basic theoretical assumptions of research on learning with hypertext/hypermedia. Focuses on whether the results of research on hypertext/hypermedia-based learning support these assumptions. Results of empirical studies and theoretical analysis reveal that many research approaches have been misled by inappropriate theoretical assumptions on…

Evolution of increased phenotypic diversity enhances population performance by reducing sexual harassment in damselflies.

PubMed

Takahashi, Yuma; Kagawa, Kotaro; Svensson, Erik I; Kawata, Masakado

2014-07-18

The effect of evolutionary changes in traits and phenotypic/genetic diversity on ecological dynamics has received much theoretical attention; however, the mechanisms and ecological consequences are usually unknown. Female-limited colour polymorphism in damselflies is a counter-adaptation to male mating harassment, and thus, is expected to alter population dynamics through relaxing sexual conflict. Here we show the side effect of the evolution of female morph diversity on population performance (for example, population productivity and sustainability) in damselflies. Our theoretical model incorporating key features of the sexual interaction predicts that the evolution of increased phenotypic diversity will reduce overall fitness costs to females from sexual conflict, which in turn will increase productivity, density and stability of a population. Field data and mesocosm experiments support these model predictions. Our study suggests that increased phenotypic diversity can enhance population performance that can potentially reduce extinction rates and thereby influence macroevolutionary processes.

Anatomy of the Photodissociation Region in the Orion Bar

NASA Technical Reports Server (NTRS)

Tielens, A. G. G. M.; Meixner, M. M.; vanderWerf, P. P.; Bregman, J.; Tauber, J. A.; Stutzki, J.; Rank, D.

1993-01-01

Much of the interstellar gas resides in photodissociation regions whose chemistry and energy balance is controlled by the flux of far-ultraviolet radiation upon them. These photons can ionize and dissociate molecules and heat the gas through the photoelectric effect working on dust grains. These regions have been extensively modeled theoretically, but detailed observational studies are few. Mapping of the prominent Orion Bar photo-dissociation region at wavelengths corresponding to the carbon-hydrogen stretching mode of polycyclic aromatic hydrocarbons, the 1-0 S(l) line of molecular hydrogen, and the J = 1-0 rotational line of carbon monoxide allows the penetration of the far-ultraviolet radiation into the cloud to be traced. The results strongly support the theoretical models and show conclusively that the incident far-ultraviolet radiation field, not shocks as has sometimes been proposed, is responsible for the emission in the Orion Bar.

Whirling and stability of flywheel systems, part I: Derivation of combined and lumped parameter models

NASA Astrophysics Data System (ADS)

Ramanujam, G.; Bert, C. W.

1983-06-01

The objective of this paper is to provide a theoretical foundation to predict many aspects of dynamic behavior of flywheel systems when spin-tested with a quill shaft support and driven by an air turbine. Theoretical analyses for the following are presented: (1) determination of natural frequencies (or for brevity critical speeds of various orders), (2) Routh-type stability analysis to determine the stability limits (i.e., the speed range within which small perturbations attenuate rather than cause catastrophic failure), and (3) forced whirling analysis to estimate the response of major components of the system to flywheel mass eccentricity and initial tilt. For the first and third kinds of analyses, two different mathematical models of the generic system are investigated. One is a seven-degree-of-freedom lumped parameter analysis, while the other is a combined distributed and lumped parameter analysis.

[Proposing a physiological model for Emergency Department. Operating principles, classification of overcrowding and guidelines for redesign].

PubMed

Herrera Carranza, M; Aguado Correa, F; Padilla Garrido, N; López Camacho, F

2017-04-30

The operation of Emergency Departments (ED) is determined by demand, their own organizational structures and the connection to other medical care levels. When these elements are not simultaneous, it hinders patient flow and decreases capacity, making it necessary to employ a systemic approach to the chain of emergency care as a single operational entity. With this theoretical orientation, we suggest a conceptual model similar to the physiological cardiac output, in which the preload is the demand, the contractile or flow pump is the organizational structure, the afterload is the hospital, the pre-ED valve is primary care and outpatient emergencies, and the post-ED valve is the diagnostic support services and the specialist consultants. Based on this theoretical approach we classify the different types of ED overcrowding and systematise its causes and the different waiting lists that it generates, which can help to redesign the service and avoid its saturation.

Direct-to-consumer-advertising of prescription medicines: a theoretical approach to understanding.

PubMed

Harker, Michael; Harker, Debra

2007-01-01

The pharmaceutical industry is a leader in research and development investment. New treatments need to be communicated to the market, and consumers are increasingly interested in learning about new drugs. Direct to consumer advertising of prescription medicines (DTCA) is a controversial practice where many of the arguments for and against are not supported by strong evidence. This paper aims to contribute to a research agenda that is forming in this area. The paper reports on a systematic review that was conducted and applies accepted theoretical models to the DTCA context. The systematic review methodology is widely accepted in the medical sector and is successfully applied here in the marketing field. The hierarchy of effects model is specifically applied to DTCA with a clear emphasis on consumer rights, empowerment, protection and knowledge. This paper provides healthcare practitioners with insight into how consumers process DTCA messages and provides guidance into how to assist in this message processing.

Outcome regimes of binary raindrop collisions

NASA Astrophysics Data System (ADS)

Testik, Firat Y.

2009-11-01

This study delineates the physical conditions that are responsible for the occurrence of main outcome regimes (i.e., bounce, coalescence, and breakup) for binary drop collisions with a precipitation microphysics perspective. Physical considerations based on the collision kinetic energy and the surface energies of the colliding drops lead to the development of a theoretical regime diagram for the drop/raindrop collision outcomes in the We- p plane ( We — Weber number, p — raindrop diameter ratio). This theoretical regime diagram is supported by laboratory experimental observations of drop collisions using high-speed imaging. Results of this fundamental study bring in new insights into the quantitative understanding of drop dynamics, applications of which extend beyond precipitation microphysics. In particular, results of this drop collision study are expected to give impetus to the physics-based dynamic modeling of the drop size distributions that is essential for various typical modern engineering applications, including numerical modeling of evolution of raindrop size distribution in rain shaft.

Formation and stability of twisted ribbons in mixtures of rod-like fd-virus and non-adsorbing polymer

NASA Astrophysics Data System (ADS)

Dogic, Z.; Didonna, B.; Bryning, M.; Lubensky, T. C.; Yodh, A. G.; Janmey, P. A.

2003-03-01

We are investigating the behavior of mixtures of monodisperse fd-virus rods and non-adsorbing polymer. We observe the formation of isolated smectic disks. The single smectic disk is of a monolayer of aligned rods while its thickness equal to the length of a single rod. As disks coalesce they undergo shape transformations from flat structures to elongated twisted ribbons. A theoretical model is formulated wherein the chirality of the molecule favors the formation of the elongated ribbon structure while the line tension favors formation of untwisted disks. To check the validity of the theoretical model line tension and twist constants are experimentally measured. The line tension is deduced from thermal fluctuations of the interface. The twist constant is determined by unwinding the twisted ribbons using optical tweezers. This work is partially supported by NSF grants DMR-0203378, the PENN MRSEC, DMR-0079909, and NASA grant NAG8-2172.

Dopamine prediction errors in reward learning and addiction: from theory to neural circuitry

PubMed Central

Keiflin, Ronald; Janak, Patricia H.

2015-01-01

Summary Midbrain dopamine (DA) neurons are proposed to signal reward prediction error (RPE), a fundamental parameter in associative learning models. This RPE hypothesis provides a compelling theoretical framework for understanding DA function in reward learning and addiction. New studies support a causal role for DA-mediated RPE activity in promoting learning about natural reward; however, this question has not been explicitly tested in the context of drug addiction. In this review, we integrate theoretical models with experimental findings on the activity of DA systems, and on the causal role of specific neuronal projections and cell types, to provide a circuit-based framework for probing DA-RPE function in addiction. By examining error-encoding DA neurons in the neural network in which they are embedded, hypotheses regarding circuit-level adaptations that possibly contribute to pathological error-signaling and addiction can be formulated and tested. PMID:26494275

Epidemic threshold of the susceptible-infected-susceptible model on complex networks

NASA Astrophysics Data System (ADS)

Lee, Hyun Keun; Shim, Pyoung-Seop; Noh, Jae Dong

2013-06-01

We demonstrate that the susceptible-infected-susceptible (SIS) model on complex networks can have an inactive Griffiths phase characterized by a slow relaxation dynamics. It contrasts with the mean-field theoretical prediction that the SIS model on complex networks is active at any nonzero infection rate. The dynamic fluctuation of infected nodes, ignored in the mean field approach, is responsible for the inactive phase. It is proposed that the question whether the epidemic threshold of the SIS model on complex networks is zero or not can be resolved by the percolation threshold in a model where nodes are occupied in degree-descending order. Our arguments are supported by the numerical studies on scale-free network models.

Evaluating Instrument Quality in Science Education: Rasch-based analyses of a Nature of Science test

NASA Astrophysics Data System (ADS)

Neumann, Irene; Neumann, Knut; Nehm, Ross

2011-07-01

Given the central importance of the Nature of Science (NOS) and Scientific Inquiry (SI) in national and international science standards and science learning, empirical support for the theoretical delineation of these constructs is of considerable significance. Furthermore, tests of the effects of varying magnitudes of NOS knowledge on domain-specific science understanding and belief require the application of instruments validated in accordance with AERA, APA, and NCME assessment standards. Our study explores three interrelated aspects of a recently developed NOS instrument: (1) validity and reliability; (2) instrument dimensionality; and (3) item scales, properties, and qualities within the context of Classical Test Theory and Item Response Theory (Rasch modeling). A construct analysis revealed that the instrument did not match published operationalizations of NOS concepts. Rasch analysis of the original instrument-as well as a reduced item set-indicated that a two-dimensional Rasch model fit significantly better than a one-dimensional model in both cases. Thus, our study revealed that NOS and SI are supported as two separate dimensions, corroborating theoretical distinctions in the literature. To identify items with unacceptable fit values, item quality analyses were used. A Wright Map revealed that few items sufficiently distinguished high performers in the sample and excessive numbers of items were present at the low end of the performance scale. Overall, our study outlines an approach for how Rasch modeling may be used to evaluate and improve Likert-type instruments in science education.

Analysis of the implementation of a personalized care model in diabetes mellitus as an example of chronic disease with information and communication technology support.

PubMed

López-Martínez, N; Segú, J L; Vázquez-Castro, J; Brosa, M; Bohigas, L; Comellas, M J; Kalfhaus, L

2017-04-01

Diabetes mellitus affects 13.8% of the adult population in Spain, representing some 8.2% of total Spanish health spending, which may be reduced by optimizing treatment and disease monitoring. Areas covered: This perspective article aims to evaluate the possible clinical and economic outcomes of implementing a theoretical personalized care model in diabetes supported by information and communications technology in Spain vs. conventional care. Moreover, we assessed the value of emminens® eConecta, a solution designed to support the operational implementation of this model, which enables the connection and participation of patients and health professionals, facilitates patient education, decision-making, access to information, and data analysis. We carried out a review of the available evidence, consultations with experts and a clinical and cost estimation. Expert commentary: The experts consulted considered that the proposed model is consistent with Spanish strategies on chronicity, supports the management of chronicity/diabetes, and may improve the most important aspects of disease management. In the literature, this type of care models improved or provided equal disease control compared with conventional care, potentiated self-management strategies and reduced the high use of resources. Cost estimation showed a reduction of -12% in total direct costs and around -34% in the costs of outpatient visits.

A model of individualized canonical microcircuits supporting cognitive operations

PubMed Central

Peterson, Andre D. H.; Haueisen, Jens; Knösche, Thomas R.

2017-01-01

Major cognitive functions such as language, memory, and decision-making are thought to rely on distributed networks of a large number of basic elements, called canonical microcircuits. In this theoretical study we propose a novel canonical microcircuit model and find that it supports two basic computational operations: a gating mechanism and working memory. By means of bifurcation analysis we systematically investigate the dynamical behavior of the canonical microcircuit with respect to parameters that govern the local network balance, that is, the relationship between excitation and inhibition, and key intrinsic feedback architectures of canonical microcircuits. We relate the local behavior of the canonical microcircuit to cognitive processing and demonstrate how a network of interacting canonical microcircuits enables the establishment of spatiotemporal sequences in the context of syntax parsing during sentence comprehension. This study provides a framework for using individualized canonical microcircuits for the construction of biologically realistic networks supporting cognitive operations. PMID:29200435

Long-Range Interaction Forces between Polymer-Supported Lipid Bilayer Membranes

PubMed Central

Seitz, Markus; Park, Chad K.; Wong, Joyce Y.

2009-01-01

Much of the short-range forces and structures of softly supported DMPC bilayers has been described previously. However, one interesting feature of the measured force–distance profile that remained unexplained is the presence of a long-range exponentially decaying repulsive force that is not observed between rigidly supported bilayers on solid mica substrate surfaces. This observation is discussed in detail here based on recent static and dynamic surface force experiments. The repulsive forces in the intermediate distance regime (mica–mica separations from 15 to 40 nm) are shown to be due not to an electrostatic force between the bilayers but to compression (deswelling) of the underlying soft polyelectrolyte layer, which may be thought of as a model cytoskeleton. The experimental data can be fit by simple theoretical models of polymer interactions from which the elastic properties of the polymer layer can be deduced. PMID:21359166

'Isn't it ironic?' Beliefs about the unacceptability of emotions and emotional suppression relate to worse outcomes in fibromyalgia.

PubMed

Bowers, Hannah; Wroe, Abigail L; Pincus, Tamar

2017-05-01

Beliefs about the unacceptability of experiencing and expressing emotions have been found to be related to worse outcomes in people with persistent physical symptoms. The current study tested mediation models regarding emotional suppression, beliefs about emotions, support-seeking and global impact in fibromyalgia. One hundred eighty-two participants took part in an online questionnaire testing potential mechanisms of this relationship using mediation analysis. The model tested emotional suppression and affective distress as serial mediators of the relationship between beliefs about emotions and global impact. In parallel paths, two forms of support-seeking were tested (personal/emotional and symptom-related support-seeking) as mediators. Emotional suppression and affective distress significantly serially mediated the relationship between beliefs about emotions and global impact. Neither support-seeking variable significantly mediated this relationship. Results indicate a potential mechanism through which beliefs about emotions and global impact might relate which might provide a theoretical basis for future research on treatments for fibromyalgia.

On the Connection between Kinetic Monte Carlo and the Burton-Cabrera-Frank Theory

NASA Astrophysics Data System (ADS)

Patrone, Paul; Margetis, Dionisios; Einstein, T. L.

2013-03-01

In the many years since it was first proposed, the Burton- Cabrera-Frank (BCF) model of step-flow has been experimentally established as one of the cornerstones of surface physics. However, many questions remain regarding the underlying physical processes and theoretical assumptions that give rise to the BCF theory. In this work, we formally derive the BCF theory from an atomistic, kinetic Monte Carlo model of the surface in 1 +1 dimensions with one step. Our analysis (i) shows how the BCF theory describes a surface with a low density of adsorbed atoms, and (ii) establishes a set of near-equilibrium conditions ensuring that the theory remains valid for all times. Support for PP was provided by the NIST-ARRA Fellowship Award No. 70NANB10H026 through UMD. Support for TLE and PP was also provided by the CMTC at UMD, with ancillary support from the UMD MRSEC. Support for DM was provided by NSF DMS0847587 at UMD.

Label it or ban it? Public perceptions of nano-food labels and propositions for banning nano-food applications

NASA Astrophysics Data System (ADS)

Chuah, Agnes S. F.; Leong, Alisius D.; Cummings, Christopher L.; Ho, Shirley S.

2018-02-01

The future of nano-food largely hinges on public perceptions and willingness to accept this novel technology. The present study utilizes the scientific literacy model and psychometric paradigm as the key theoretical frameworks to examine the factors influencing public support for labeling and banning of nano-food in Singapore. Using data collected from a nationally representative survey of 1001 respondents, the findings demonstrated that attitudes toward technology, preference for natural product, science knowledge, and risk perception were found to substantially affect public support for both labeling and banning of nano-food. Conversely, attention to food safety news on traditional media and attention to nano-news on new media were only associated with public support for labeling of nano-food. Similarly, benefit perception was only significantly associated with public support for banning of nano-food. Theoretically, these findings support the growing body of literature that argues for the significant role played by predispositions, media use, science knowledge, and risk and benefit perceptions on attitude formation toward nano-food. It serves as the pioneering piece to address the aspect of banning in the field of nano-food. Practically, insights drawn from this study could aid relevant stakeholders in enlisting effecting strategies to convey the benefits of nano-food while mitigating the risk perceptions among the public.

MHD Modeling of the Sympathetic Eruptions Observed on August 1, 2010

NASA Astrophysics Data System (ADS)

Mikic, Z.; Torok, T.; Titov, V. S.; Downs, C.; Linker, J.; Lionello, R.; Riley, P.

2013-12-01

The multiple solar eruptions observed by SDO on August 1, 2010 present a special challenge to theoretical models of CME initiation. SDO captured in detail a remarkable chain of sympathetic eruptions that involved the entire visible hemisphere of the Sun (Schrijver et al. 2011). It consisted of several flares and six filament eruptions/CMEs, and triggered a geomagnetic storm on August 3 (de Toma et al. 2010). This series of eruptions was also observed by the two STEREO spacecraft. This collection of observations presents a unique opportunity to understand sympathetic eruptions theoretically. We have previously simulated the three principal filament eruptions (and their associated CMEs) that characterized this event. We have had some success in reproducing their observed synchronicity. We will present further simulations that attempt to get a better match with observations. Such simulations will help us to understand the possible mechanisms by which the various filament eruptions/CMEs may be linked. The modeling of such events is very useful for incorporation into future space weather prediction models. Research supported by NASA's Heliophysics Theory and Living With a Star Programs, and NSF/FESD.

Something's got to give: the effects of dual-goal difficulty, goal progress, and expectancies on resource allocation.

PubMed

Schmidt, Aaron M; Dolis, Chad M

2009-05-01

The current study developed and tested a model of the interplay among goal difficulty, goal progress, and expectancy over time in influencing resource allocation toward competing demands. The results provided broad support for the theoretical model. As predicted, dual-goal expectancy-the perceived likelihood of meeting both goals in competition-played a central role, moderating the relationship between relative goal progress and resource allocation. Dual-goal difficulty was also found to exert an important influence on multiple-goal self-regulation. Although it did not influence total productivity across both tasks combined, it did combine with other model components to influence the relative emphasis of one task over another. These results suggest that the cumulative demands placed by multiple difficult goals may exceed individuals' perceived capabilities and may lead to partial or total abandonment of 1 goal to ensure attainment of the other. The model helps shed light on some of the conflicting theoretical propositions and empirical results obtained in prior work. Implications for theory and research regarding multiple-goal self-regulation are discussed. (c) 2009 APA, all rights reserved.

A framework for the study of coping, illness behaviour and outcomes.

PubMed

Shaw, C

1999-05-01

This paper presents a theoretical framework for the study of coping, illness attribution, health behaviour and outcomes. It is based upon models developed within health psychology and aims to provide a theoretical basis for nurse researchers to utilize psychosocial variables. It is an interactionist model which views outcomes as dependent upon both situation and person variables. The situation is viewed as the health threat or illness symptoms as well as the psychosocial context within which the person is operating. This context includes socio-economic factors, social support, social norms, and external factors such as the mass media. The experience of health threat is dependent upon individual appraisal, and the framework incorporates Folkman and Lazarus' transactional model of stress, as well as Leventhal's illness representation model. Behaviour and the perception of threat are also dependent upon outcome expectancies and the appraisal of one's own coping resources, and so the concepts of locus of control and self-efficacy are also incorporated. This framework allows one to identify determinants of behaviour and outcome, and will aid nurses in identifying areas for psycho-social intervention.

The impact of electrostatic correlations on Dielectrophoresis of Non-conducting Particles

NASA Astrophysics Data System (ADS)

Alidoosti, Elaheh; Zhao, Hui

2017-11-01

The dipole moment of a charged, dielectric, spherical particle under the influence of a uniform alternating electric field is computed theoretically and numerically by solving the modified continuum Poisson-Nernst-Planck (PNP) equations accounting for ion-ion electrostatic correlations that is important at concentrated electrolytes (Phys. Rev. Lett. 106, 2011). The dependence on the frequency, zeta potential, electrostatic correlation lengths, and double layer thickness is thoroughly investigated. In the limit of thin double layers, we carry out asymptotic analysis to develop simple models which are in good agreement with the modified PNP model. Our results suggest that the electrostatic correlations have a complicated impact on the dipole moment. As the electrostatic correlations length increases, the dipole moment decreases, initially, reach a minimum, and then increases since the surface conduction first decreases and then increases due to the ion-ion correlations. The modified PNP model can improve the theoretical predictions particularly at low frequencies where the simple model can't qualitatively predict the dipole moment. This work was supported, in part, by NIH R15GM116039.

Theory, Modeling, Software and Hardware Development for Analytical and Computational Materials Science

NASA Technical Reports Server (NTRS)

Young, Gerald W.; Clemons, Curtis B.

2004-01-01

The focus of this Cooperative Agreement between the Computational Materials Laboratory (CML) of the Processing Science and Technology Branch of the NASA Glenn Research Center (GRC) and the Department of Theoretical and Applied Mathematics at The University of Akron was in the areas of system development of the CML workstation environment, modeling of microgravity and earth-based material processing systems, and joint activities in laboratory projects. These efforts complement each other as the majority of the modeling work involves numerical computations to support laboratory investigations. Coordination and interaction between the modelers, system analysts, and laboratory personnel are essential toward providing the most effective simulations and communication of the simulation results. Toward these means, The University of Akron personnel involved in the agreement worked at the Applied Mathematics Research Laboratory (AMRL) in the Department of Theoretical and Applied Mathematics while maintaining a close relationship with the personnel of the Computational Materials Laboratory at GRC. Network communication between both sites has been established. A summary of the projects we undertook during the time period 9/1/03 - 6/30/04 is included.

A computational model-based validation of Guyton's analysis of cardiac output and venous return curves

NASA Technical Reports Server (NTRS)

Mukkamala, R.; Cohen, R. J.; Mark, R. G.

2002-01-01

Guyton developed a popular approach for understanding the factors responsible for cardiac output (CO) regulation in which 1) the heart-lung unit and systemic circulation are independently characterized via CO and venous return (VR) curves, and 2) average CO and right atrial pressure (RAP) of the intact circulation are predicted by graphically intersecting the curves. However, this approach is virtually impossible to verify experimentally. We theoretically evaluated the approach with respect to a nonlinear, computational model of the pulsatile heart and circulation. We developed two sets of open circulation models to generate CO and VR curves, differing by the manner in which average RAP was varied. One set applied constant RAPs, while the other set applied pulsatile RAPs. Accurate prediction of intact, average CO and RAP was achieved only by intersecting the CO and VR curves generated with pulsatile RAPs because of the pulsatility and nonlinearity (e.g., systemic venous collapse) of the intact model. The CO and VR curves generated with pulsatile RAPs were also practically independent. This theoretical study therefore supports the validity of Guyton's graphical analysis.

Microwave dielectric behavior of vegetation material

NASA Technical Reports Server (NTRS)

Elrayes, Mohamed A.; Ulaby, Fawwaz T.

1987-01-01

The microwave dielectric behavior of vegetation was examined through the development of theoretical models involving dielectric dispersion by both bound and free water and supported by extensive dielectric measurements conducted over a wide range of conditions. The experimental data were acquired using an open-ended coaxial probe that was developed for sensing the dielectric constant of thin layers of materials, such as leaves, from measurements of the complex reflection coefficient using a network analyzer. The probe system was successfully used to record the spectral variation of the dielectric constant over a wide frequency range extending from 0.5 to 20.4 GHz at numerous temperatures between -40 to +40 C. The vegetation samples were measured over a wide range of moisture conditions. To model the dielectric spectrum of the bound water component of the water included in vegetation, dielectric measurements were made for several sucrose-water solutions as analogs for the situation in vegetation. The results were used in conjunction with the experimental data for leaves to determine some of the constant coefficients in the theoretical models. Two models, both of which provide good fit to the data, are proposed.

A new discriminative kernel from probabilistic models.

PubMed

Tsuda, Koji; Kawanabe, Motoaki; Rätsch, Gunnar; Sonnenburg, Sören; Müller, Klaus-Robert

2002-10-01

Recently, Jaakkola and Haussler (1999) proposed a method for constructing kernel functions from probabilistic models. Their so-called Fisher kernel has been combined with discriminative classifiers such as support vector machines and applied successfully in, for example, DNA and protein analysis. Whereas the Fisher kernel is calculated from the marginal log-likelihood, we propose the TOP kernel derived; from tangent vectors of posterior log-odds. Furthermore, we develop a theoretical framework on feature extractors from probabilistic models and use it for analyzing the TOP kernel. In experiments, our new discriminative TOP kernel compares favorably to the Fisher kernel.

Study of helicopterroll control effectiveness criteria

NASA Technical Reports Server (NTRS)

Heffley, Robert K.; Bourne, Simon M.; Curtiss, Howard C., Jr.; Hindson, William S.; Hess, Ronald A.

1986-01-01

A study of helicopter roll control effectiveness based on closed-loop task performance measurement and modeling is presented. Roll control critieria are based on task margin, the excess of vehicle task performance capability over the pilot's task performance demand. Appropriate helicopter roll axis dynamic models are defined for use with analytic models for task performance. Both near-earth and up-and-away large-amplitude maneuvering phases are considered. The results of in-flight and moving-base simulation measurements are presented to support the roll control effectiveness criteria offered. This Volume contains the theoretical analysis, simulation results and criteria development.

Using an Adaptive Expertise Lens to Understand the Quality of Teachers' Classroom Implementation of Computer-Supported Complex Systems Curricula in High School Science

ERIC Educational Resources Information Center

Yoon, Susan A.; Koehler-Yom, Jessica; Anderson, Emma; Lin, Joyce; Klopfer, Eric

2015-01-01

Background: This exploratory study is part of a larger-scale research project aimed at building theoretical and practical knowledge of complex systems in students and teachers with the goal of improving high school biology learning through professional development and a classroom intervention. Purpose: We propose a model of adaptive expertise to…

The Online Learning Environment--A New Model Using Social Constructivism and the Concept of "Ba" as a Theoretical Framework

ERIC Educational Resources Information Center

Bryceson, Kim

2007-01-01

Organisations that provide education are businesses and, as such, are not immune from the impact that the Internet has had in recent years, both on the way organisations conduct their business "and" as a business supporting technology. Indeed, the use of the Internet as a facilitating mechanism for educational course delivery has been growing…

Support of research in X-ray astronomy

NASA Technical Reports Server (NTRS)

Garmire, G.

1983-01-01

Activities described include: (1) the evaluation of CCD detectors for X-ray astronomy applications; (2) contributions to the development of an imaging gas scintillation proportional counter; (3) the evaluation of certain metal oxide crystals as potential radiation detectors; (4) optical observations and searches for X-ray sources discovered by the HEAO-1 A2 experiment; and (5) theoretical modeling of nonequilibrium ionization structure of supernova remnants.

New stereoselective intramolecular

PubMed

Alajarin; Vidal; Tovar; Ramirez De Arellano MC; Cossio; Arrieta; Lecea

2000-11-03

Efficient 1,4-asymmetric induction has been achieved in the highly stereocontrolled intramolecular [2 + 2] cycloadditions between ketenimines and imines, leading to 1,2-dihydroazeto[2, 1-b]quinazolines. The chiral methine carbon adjacent to the iminic nitrogen controls the exclusive formation of the cycloadducts with relative trans configuration at C2 and C8. The stepwise mechanistic model, based on theoretical calculations, fully supports the stereochemical outcome of these cycloadditions.

Preparation and Validation of Mentor Self-Efficacy and Perceived Program Support Scales (M-SEPPS): An Empirical Study in Mentoring Intervention Models

ERIC Educational Resources Information Center

Calvery, Suzannah Vallejo

2013-01-01

Mentoring research to date focuses on outcomes related to program goals and theoretical background, and almost all of these relate to the experience of the mentee. Very little research has been completed on the other side of the dyad--the mentor--despite the fact that mentor expectations and experience contribute significantly to the perceived…

The threshold of a stochastic avian-human influenza epidemic model with psychological effect

NASA Astrophysics Data System (ADS)

Zhang, Fengrong; Zhang, Xinhong

2018-02-01

In this paper, a stochastic avian-human influenza epidemic model with psychological effect in human population and saturation effect within avian population is investigated. This model describes the transmission of avian influenza among avian population and human population in random environments. For stochastic avian-only system, persistence in the mean and extinction of the infected avian population are studied. For the avian-human influenza epidemic system, sufficient conditions for the existence of an ergodic stationary distribution are obtained. Furthermore, a threshold of this stochastic model which determines the outcome of the disease is obtained. Finally, numerical simulations are given to support the theoretical results.

Statistical analysis of financial returns for a multiagent order book model of asset trading

NASA Astrophysics Data System (ADS)

Preis, Tobias; Golke, Sebastian; Paul, Wolfgang; Schneider, Johannes J.

2007-07-01

We recently introduced a realistic order book model [T. Preis , Europhys. Lett. 75, 510 (2006)] which is able to generate the stylized facts of financial markets. We analyze this model in detail, explain the consequences of the use of different groups of traders, and focus on the foundation of a nontrivial Hurst exponent based on the introduction of a market trend. Our order book model supports the theoretical argument that a nontrivial Hurst exponent implies not necessarily long-term correlations. A coupling of the order placement depth to the market trend can produce fat tails, which can be described by a truncated Lévy distribution.

Application of a theoretical model to evaluate COPD disease management.

PubMed

Lemmens, Karin M M; Nieboer, Anna P; Rutten-Van Mölken, Maureen P M H; van Schayck, Constant P; Asin, Javier D; Dirven, Jos A M; Huijsman, Robbert

2010-03-26

Disease management programmes are heterogeneous in nature and often lack a theoretical basis. An evaluation model has been developed in which theoretically driven inquiries link disease management interventions to outcomes. The aim of this study is to methodically evaluate the impact of a disease management programme for patients with chronic obstructive pulmonary disease (COPD) on process, intermediate and final outcomes of care in a general practice setting. A quasi-experimental research was performed with 12-months follow-up of 189 COPD patients in primary care in the Netherlands. The programme included patient education, protocolised assessment and treatment of COPD, structural follow-up and coordination by practice nurses at 3, 6 and 12 months. Data on intermediate outcomes (knowledge, psychosocial mediators, self-efficacy and behaviour) and final outcomes (dyspnoea, quality of life, measured by the CRQ and CCQ, and patient experiences) were obtained from questionnaires and electronic registries. Implementation of the programme was associated with significant improvements in dyspnoea (p < 0.001) and patient experiences (p < 0.001). No significant improvement was found in mean quality of life scores. Improvements were found in several intermediate outcomes, including investment beliefs (p < 0.05), disease-specific knowledge (p < 0.01; p < 0.001) and medication compliance (p < 0.01). Overall, process improvement was established. The model showed associations between significantly improved intermediate outcomes and improvements in quality of life and dyspnoea. The application of a theory-driven model enhances the design and evaluation of disease management programmes aimed at improving health outcomes. This study supports the notion that a theoretical approach strengthens the evaluation designs of complex interventions. Moreover, it provides prudent evidence that the implementation of COPD disease management programmes can positively influence outcomes of care.

Application of a theoretical model to evaluate COPD disease management

PubMed Central

2010-01-01

Background Disease management programmes are heterogeneous in nature and often lack a theoretical basis. An evaluation model has been developed in which theoretically driven inquiries link disease management interventions to outcomes. The aim of this study is to methodically evaluate the impact of a disease management programme for patients with chronic obstructive pulmonary disease (COPD) on process, intermediate and final outcomes of care in a general practice setting. Methods A quasi-experimental research was performed with 12-months follow-up of 189 COPD patients in primary care in the Netherlands. The programme included patient education, protocolised assessment and treatment of COPD, structural follow-up and coordination by practice nurses at 3, 6 and 12 months. Data on intermediate outcomes (knowledge, psychosocial mediators, self-efficacy and behaviour) and final outcomes (dyspnoea, quality of life, measured by the CRQ and CCQ, and patient experiences) were obtained from questionnaires and electronic registries. Results Implementation of the programme was associated with significant improvements in dyspnoea (p < 0.001) and patient experiences (p < 0.001). No significant improvement was found in mean quality of life scores. Improvements were found in several intermediate outcomes, including investment beliefs (p < 0.05), disease-specific knowledge (p < 0.01; p < 0.001) and medication compliance (p < 0.01). Overall, process improvement was established. The model showed associations between significantly improved intermediate outcomes and improvements in quality of life and dyspnoea. Conclusions The application of a theory-driven model enhances the design and evaluation of disease management programmes aimed at improving health outcomes. This study supports the notion that a theoretical approach strengthens the evaluation designs of complex interventions. Moreover, it provides prudent evidence that the implementation of COPD disease management programmes can positively influence outcomes of care. PMID:20346135

Vagal activity is quadratically related to prosocial traits, prosocial emotions, and observer perceptions of prosociality.

PubMed

Kogan, Aleksandr; Oveis, Christopher; Carr, Evan W; Gruber, June; Mauss, Iris B; Shallcross, Amanda; Impett, Emily A; van der Lowe, Ilmo; Hui, Bryant; Cheng, Cecilia; Keltner, Dacher

2014-12-01

In the present article, we introduce the quadratic vagal activity-prosociality hypothesis, a theoretical framework for understanding the vagus nerve's involvement in prosociality. We argue that vagus nerve activity supports prosocial behavior by regulating physiological systems that enable emotional expression, empathy for others' mental and emotional states, the regulation of one's own distress, and the experience of positive emotions. However, we contend that extremely high levels of vagal activity can be detrimental to prosociality. We present 3 studies providing support for our model, finding consistent evidence of a quadratic relationship between respiratory sinus arrhythmia--the degree to which the vagus nerve modulates the heart rate--and prosociality. Individual differences in vagal activity were quadratically related to prosocial traits (Study 1), prosocial emotions (Study 2), and outside ratings of prosociality by complete strangers (Study 3). Thus, too much or too little vagal activity appears to be detrimental to prosociality. The present article provides the 1st theoretical and empirical account of the nonlinear relationship between vagal activity and prosociality.

Food web complexity and stability across habitat connectivity gradients.

PubMed

LeCraw, Robin M; Kratina, Pavel; Srivastava, Diane S

2014-12-01

The effects of habitat connectivity on food webs have been studied both empirically and theoretically, yet the question of whether empirical results support theoretical predictions for any food web metric other than species richness has received little attention. Our synthesis brings together theory and empirical evidence for how habitat connectivity affects both food web stability and complexity. Food web stability is often predicted to be greatest at intermediate levels of connectivity, representing a compromise between the stabilizing effects of dispersal via rescue effects and prey switching, and the destabilizing effects of dispersal via regional synchronization of population dynamics. Empirical studies of food web stability generally support both this pattern and underlying mechanisms. Food chain length has been predicted to have both increasing and unimodal relationships with connectivity as a result of predators being constrained by the patch occupancy of their prey. Although both patterns have been documented empirically, the underlying mechanisms may differ from those predicted by models. In terms of other measures of food web complexity, habitat connectivity has been empirically found to generally increase link density but either reduce or have no effect on connectance, whereas a unimodal relationship is expected. In general, there is growing concordance between empirical patterns and theoretical predictions for some effects of habitat connectivity on food webs, but many predictions remain to be tested over a full connectivity gradient, and empirical metrics of complexity are rarely modeled. Closing these gaps will allow a deeper understanding of how natural and anthropogenic changes in connectivity can affect real food webs.

Dynamic analysis of periodic vibration suppressors with multiple secondary oscillators

NASA Astrophysics Data System (ADS)

Ma, Jiangang; Sheng, Meiping; Guo, Zhiwei; Qin, Qi

2018-06-01

A periodic vibration suppressor with multiple secondary oscillators is examined in this paper to reduce the low-frequency vibration. The band-gap properties of infinite periodic structure and vibration transmission properties of finite periodic structure attached with secondary oscillators with arbitrary degree of freedom are thoroughly analyzed by the plane-wave-expansion method. A simply supported plate with a periodic rectangular array of vibration suppressors is considered. The dynamic model of this periodic structure is established and the equation of harmonic vibration response is theoretically derived and numerically examined. Compared with the simply supported plate without attached suppressors, the proposed plate can obtain better vibration control, and the vibration response can be effectively reduced in several frequency bands owing to the multiple band-gap property. By analyzing the modal properties of the periodic vibration suppressors, the relationship between modal frequencies and the parameters of spring stiffness and mass is established. With the numerical results, the design guidance of the locally resonant structure with multiple secondary oscillators is proposed to provide practical guidance for application. Finally, a practical periodic specimen is designed and fabricated, and then an experiment is carried out to validate the effectiveness of periodic suppressors in the reality. The results show that the experimental band gaps have a good coincidence with those in the theoretical model, and the low-frequency vibration of the plate with periodic suppressors can be effectively reduced in the tuned band gaps. Both the theoretical results and experimental results prove that the design method is effective and the structure with periodic suppressors has a promising application in engineering.

[Examination of the Young maladaptive schemes in a group of Gamblers Anonymous].

PubMed

Katona, Zsuzsa; Körmendi, Attila

2012-01-01

Literature of gambling addiction has become widespread in last years. Many studies were written about the vulnerability factors helping the development of addiction, theoretical models, comorbid problems and therapy possibilities. Currently there is no integrated theoretical model that could explain sufficiently the development and maintenance of pathological gambling. The treatment issue is also unresolved. Cognitive psychology is a dynamically developing field of psychology and good results are achieved in gambling treatment with applying cognitive techniques. Jeffrey Young's schema-focused therapy is a recent theoretical and therapeutic direction within cognitive psychology which emphasizes the necessity of emotional changes beside rational ones in the interest of efficiency. The purpose of our research is to examine and analyse active maladaptive schemas among gamblers who are members of Gamblers Anonymous self-help group. 23 control persons and 23 gamblers associated with support group of Gamblers Anonymous took part in our research. The severity of gambling behaviour was measured by Gamblers Anonymous Twenty Questions. For exploring maladaptive schemas we used the shorter 114-item version of the Young Schema Questionnaire (YSQ-S3). All the examined gamblers were considered as problem gamblers based on Gamblers Anonymous Twenty Questions. In the control group there where no active schemas while in the group of gamblers several schemas (Emotional deprivation, Self-sacrifice, Recognition seeking, Emotional inhibition, Unrelenting standards, Self-punitiveness, Insufficient self-control) showed activity. Active schemas show similarity in their matter with main establishments of researches about gamblers and support the role of impulsivity, narcissistic traits, self-medicalization and emotional deprivation in the development and maintenance of pathological gambling.

The Five Attributes of a Supportive Midwifery Practice Climate: A Review of the Literature.

PubMed

Thumm, E Brie; Flynn, Linda

2018-01-01

A supportive work climate is associated with decreased burnout and attrition, and increased job satisfaction and employee health. A review of the literature was conducted in order to determine the unique attributes of a supportive practice climate for midwives. The midwifery literature was reviewed and synthesized using concept analysis technique guided by literature from related professions. The search was conducted primarily in PubMed, CINAHL, Web of Science, and Google Scholar. Articles were included if they were conducted between 2006 and 2016 and addressed perceptions of the midwifery practice climate as it related to patient, provider, and organizational outcomes. The literature identified 5 attributes consistent with a supportive midwifery practice climate: effective leadership, adequate resources, collaboration, control of one's work, and support of the midwifery model of care. Effective leadership styles include situational and transformational, and 9 traits of effective leaders are specified. Resources consist of time, personnel, supplies, and equipment. Collaboration encompasses relationships with all members of the health care team, including midwives inside and outside of one's practice. Additionally, the patients are considered collaborating members of the team. Characteristics of effective collaboration include a shared vision, role clarity, and respectful communication. Support for the midwifery model of care includes value congruence, developing relationships with women, and providing high-quality care. The attributes of a supportive midwifery practice climate are generally consistent with theoretical models of supportive practice climates of advanced practice nurses and physicians, with the exception of a more inclusive definition of collaboration and support of the midwifery model of care. The proposed Midwifery Practice Climate Model can guide instrument development, determining relationships between the attributes of the practice climate and outcomes, and creating interventions to improve the practice climate, workforce stability, and patient outcomes. © 2018 by the American College of Nurse-Midwives.

The transfer and implementation of an Aboriginal Australian wellbeing program: a grounded theory study

PubMed Central

2013-01-01

Background The concepts and standard practices of implementation, largely originating in developed countries, cannot necessarily be simply transferred into diverse cultural contexts. There has been relative inattention in the implementation science literature paid to the implementation of interventions targeting minority Indigenous populations within developed countries. This suggests that the implementation literature may be bypassing population groups within developed countries who suffer some of the greatest disadvantage. Within the context of Aboriginal Australian health improvement, this study considers the impact of political and cultural issues by examining the transfer and implementation of the Family Wellbeing program across 56 places over a 20-year period. Methods A theoretical model of program transfer was developed using constructivist-grounded theory methods. Data were generated by conducting in-depth interviews with 18 Aboriginal and non-Aboriginal research respondents who had been active in transferring the program. Data were categorised into higher order abstract concepts and the core impetus for and process of program transfer were identified. Results Organizations transferred the program by using it as a vehicle for supporting inside-out empowerment. The impetus to support inside-out empowerment referred to support for Aboriginal people's participation, responsibility for and control of their own affairs, and the associated ripple effects to family members, organizations, communities, and ultimately reconciliation with Australian society at large. Program transfer occurred through a multi-levelled process of embracing relatedness which included relatedness with self, others, and structural conditions; all three were necessary at both individual and organizational levels. Conclusions Similar to international implementation models, the model of supporting inside-out empowerment by embracing relatedness involved individuals, organizations, and interpersonal and inter-organizational networks. However, the model suggests that for minority Indigenous populations within developed countries, implementation approaches may require greater attention to the empowering nature of the intervention and its implementation, and multiple levels of relatedness by individuals and organizations with self, others, and the structural conditions. Key elements of the theoretical model provide a useful blueprint to inform the transfer of other empowerment programs to minority Indigenous and other disadvantaged populations on a case-by-case basis. PMID:24171867

The transfer and implementation of an Aboriginal Australian wellbeing program: a grounded theory study.

PubMed

McCalman, Janya R

2013-10-31

The concepts and standard practices of implementation, largely originating in developed countries, cannot necessarily be simply transferred into diverse cultural contexts. There has been relative inattention in the implementation science literature paid to the implementation of interventions targeting minority Indigenous populations within developed countries. This suggests that the implementation literature may be bypassing population groups within developed countries who suffer some of the greatest disadvantage. Within the context of Aboriginal Australian health improvement, this study considers the impact of political and cultural issues by examining the transfer and implementation of the Family Wellbeing program across 56 places over a 20-year period. A theoretical model of program transfer was developed using constructivist-grounded theory methods. Data were generated by conducting in-depth interviews with 18 Aboriginal and non-Aboriginal research respondents who had been active in transferring the program. Data were categorised into higher order abstract concepts and the core impetus for and process of program transfer were identified. Organizations transferred the program by using it as a vehicle for supporting inside-out empowerment. The impetus to support inside-out empowerment referred to support for Aboriginal people's participation, responsibility for and control of their own affairs, and the associated ripple effects to family members, organizations, communities, and ultimately reconciliation with Australian society at large. Program transfer occurred through a multi-levelled process of embracing relatedness which included relatedness with self, others, and structural conditions; all three were necessary at both individual and organizational levels. Similar to international implementation models, the model of supporting inside-out empowerment by embracing relatedness involved individuals, organizations, and interpersonal and inter-organizational networks. However, the model suggests that for minority Indigenous populations within developed countries, implementation approaches may require greater attention to the empowering nature of the intervention and its implementation, and multiple levels of relatedness by individuals and organizations with self, others, and the structural conditions. Key elements of the theoretical model provide a useful blueprint to inform the transfer of other empowerment programs to minority Indigenous and other disadvantaged populations on a case-by-case basis.

Nonlinear oscillation of a rigid body over high- Tc superconductors supported by electro-magnetic forces

NASA Astrophysics Data System (ADS)

Sugiura, T.; Ogawa, S.; Ura, H.

2005-10-01

Characteristics of high- Tc superconducting levitation systems are no contact support and stable levitation without control. They can be applied to supporting mechanisms in machines, such as linear-drives and magnetically levitated trains. But small damping due to noncontact support and nonlinearity in the magnetic force can easily cause complicated phenomena of nonlinear dynamics. This research deals with nonlinear oscillation of a rigid bar supported at its both ends by electro-magnetic forces between superconductors and permanent magnets as a simple modeling of the above application. Deriving the equation of motion, we discussed an effect of nonlinearity in the magnetic force on dynamics of the levitated body: occurrence of combination resonance in the asymmetrical system. Numerical analyses and experiments were also carried out, and their results confirmed the above theoretical prediction.

Risk of Mortality after Spinal Cord Injury: An 8-year Prospective Study

PubMed Central

Krause, James S.; Zhai, Yusheng; Saunders, Lee L.; Carter, Rickey E.

2011-01-01

Objective To evaluate a theoretical model for mortality after spinal cord injury (SCI) by sequentially analyzing 4 sets of risk factors in relation to mortality (i.e., adding 1 set of factors to the regression equation at a time). Design Prospective cohort study of data collected in late 1997 and early 1998 with mortality status ascertained in December 2005. We evaluated the significance of 4 successive sets of predictors (biographic and injury, psychologic and environmental, behavioral, health and secondary conditions) using Cox proportional hazards modeling and built a full model based on the optimal predictors. Setting A specialty hospital. Participants 1,386 adults with traumatic SCI, at least 1 year post-injury, participated. There were 224 deaths. After eliminating cases with missing data, there were 1,209 participants, with 179 deceased at follow-up. Interventions N/A. Main Outcome Measures Mortality status was determined using the National Death Index and the Social Security Death Index. Results The final model included one environmental variable (poverty), 2 behavioral factors (prescription medication use, binge drinking), and 4 health factors or secondary conditions (hospitalizations, fractures/amputations, surgeries for pressure ulcers, probable major depression). Conclusions The results supported the major premise of the theoretical model that risk factors are more important the more proximal they are in a theoretical chain of events leading to mortality. According to this model, mortality results from declining health, precipitated by high-risk behaviors. These findings may be used to target individuals who are at high risk for early mortality as well as directing interventions to the particular risk factor. PMID:19801060

On the estimation of cooperativity in ion channel kinetics: activation free energy and kinetic mechanism of Shaker K+ channel.

PubMed

Banerjee, Kinshuk; Das, Biswajit; Gangopadhyay, Gautam

2013-04-28

In this paper, we have explored generic criteria of cooperative behavior in ion channel kinetics treating it on the same footing with multistate receptor-ligand binding in a compact theoretical framework. We have shown that the characterization of cooperativity of ion channels in terms of the Hill coefficient violates the standard Hill criteria defined for allosteric cooperativity of ligand binding. To resolve the issue, an alternative measure of cooperativity is proposed here in terms of the cooperativity index that sets a unified criteria for both the systems. More importantly, for ion channel this index can be very useful to describe the cooperative kinetics as it can be readily determined from the experimentally measured ionic current combined with theoretical modelling. We have analyzed the correlation between the voltage value and slope of the voltage-activation curve at the half-activation point and consequently determined the standard free energy of activation of the ion channel using two well-established mechanisms of cooperativity, namely, Koshland-Nemethy-Filmer (KNF) and Monod-Wyman-Changeux (MWC) models. Comparison of the theoretical results for both the models with appropriate experimental data of mutational perturbation of Shaker K(+) channel supports the experimental fact that the KNF model is more suitable to describe the cooperative behavior of this class of ion channels, whereas the performance of the MWC model is unsatisfactory. We have also estimated the mechanistic performance through standard free energy of channel activation for both the models and proposed a possible functional disadvantage in the MWC scheme.

Grave mapping in support of the search for missing persons in conflict contexts.

PubMed

Congram, Derek; Kenyhercz, Michael; Green, Arthur Gill

2017-09-01

We review the current and potential uses of Geographic Information Software (GIS) and "spatial thinking" for understanding body disposal behaviour in times of mass fatalities, particularly armed conflict contexts. The review includes observations made by the authors during the course of their academic research and professional consulting on the use of spatial analysis and GIS to support Humanitarian Forensic Action (HFA) to search for the dead, theoretical and statistical considerations in modelling grave site locations, and suggestions on how this work may be advanced further. Copyright © 2017 Elsevier B.V. All rights reserved.

Organizational support and volunteering benefits for older adults.

PubMed

Tang, Fengyan; Choi, Eunhee; Morrow-Howell, Nancy

2010-10-01

This study tested a theoretical model of volunteering benefits and examined the mechanism through which volunteering benefits older adults. This is a 2-wave study of 253 older adult volunteers serving in 10 volunteer programs. Older volunteers completed the mailed surveys in 2005 and 2006. Structural equation modeling was used to define the latent variables and to test direct and indirect relationships among organizational support, socioemotional benefits, and self-reported health. Organizational support (measured by choice of volunteer activity, training, and ongoing support) had significant direct associations with 2 latent factors of socioemotional benefits, that is, perceived contribution and personal benefits. Perceived contribution was significantly related to mental health. Additionally, older volunteers with lower socioeconomic status (SES) committed more hours and perceived more personal benefits than higher SES peers. These findings suggest that volunteer programs can provide various organizational supports to older volunteers, especially to low-SES volunteers, in order to promote the socioemotional and health benefits of volunteering to older adults. Psychological well-being of older adults can be improved through engagement in meaningful volunteer activities and contribution to others.

Development of the REFOCUS intervention to increase mental health team support for personal recovery.

PubMed

Slade, Mike; Bird, Victoria; Le Boutillier, Clair; Farkas, Marianne; Grey, Barbara; Larsen, John; Leamy, Mary; Oades, Lindsay; Williams, Julie

2015-12-01

There is an emerging evidence base about best practice in supporting recovery. This is usually framed in relation to general principles, and specific pro-recovery interventions are lacking. To develop a theoretically based and empirically defensible new pro-recovery manualised intervention--called the REFOCUS intervention. Seven systematic and two narrative reviews were undertaken. Identified evidence gaps were addressed in three qualitative studies. The findings were synthesised to produce the REFOCUS intervention, manual and model. The REFOCUS intervention comprises two components: recovery-promoting relationships and working practices. Approaches to supporting relationships comprise coaching skills training for staff, developing a shared team understanding of recovery, exploring staff values, a Partnership Project with people who use the service and raising patient expectations. Working practices comprise the following: understanding values and treatment preferences; assessing strengths; and supporting goal-striving. The REFOCUS model describes the causal pathway from the REFOCUS intervention to improved recovery. The REFOCUS intervention is an empirically supported pro-recovery intervention for use in mental health services. It will be evaluated in a multisite cluster randomised controlled trial (ISRCTN02507940). © The Royal College of Psychiatrists 2015.

Electronic health record acceptance by physicians: testing an integrated theoretical model.

PubMed

Gagnon, Marie-Pierre; Ghandour, El Kebir; Talla, Pascaline Kengne; Simonyan, David; Godin, Gaston; Labrecque, Michel; Ouimet, Mathieu; Rousseau, Michel

2014-04-01

Several countries are in the process of implementing an Electronic Health Record (EHR), but limited physicians' acceptance of this technology presents a serious threat to its successful implementation. The aim of this study was to identify the main determinants of physician acceptance of EHR in a sample of general practitioners and specialists of the Province of Quebec (Canada). We sent an electronic questionnaire to physician members of the Quebec Medical Association. We tested four theoretical models (Technology acceptance model (TAM), Extended TAM, Psychosocial Model, and Integrated Model) using path analysis and multiple linear regression analysis in order to identify the main determinants of physicians' intention to use the EHR. We evaluated the modifying effect of sociodemographic characteristics using multi-group analysis of structural weights invariance. A total of 157 questionnaires were returned. The four models performed well and explained between 44% and 55% of the variance in physicians' intention to use the EHR. The Integrated model performed the best and showed that perceived ease of use, professional norm, social norm, and demonstrability of the results are the strongest predictors of physicians' intention to use the EHR. Age, gender, previous experience and specialty modified the association between those determinants and intention. The proposed integrated theoretical model is useful in identifying which factors could motivate physicians from different backgrounds to use the EHR. Physicians who perceive the EHR to be easy to use, coherent with their professional norms, supported by their peers and patients, and able to demonstrate tangible results are more likely to accept this technology. Age, gender, specialty and experience should also be taken into account when developing EHR implementation strategies targeting physicians. Copyright © 2013 Elsevier Inc. All rights reserved.

Conceptualizing Telehealth in Nursing Practice: Advancing a Conceptual Model to Fill a Virtual Gap.

PubMed

Nagel, Daniel A; Penner, Jamie L

2016-03-01

Increasingly nurses use various telehealth technologies to deliver health care services; however, there has been a lag in research and generation of empirical knowledge to support nursing practice in this expanding field. One challenge to generating knowledge is a gap in development of a comprehensive conceptual model or theoretical framework to illustrate relationships of concepts and phenomena inherent to adoption of a broad range of telehealth technologies to holistic nursing practice. A review of the literature revealed eight published conceptual models, theoretical frameworks, or similar entities applicable to nursing practice. Many of these models focus exclusively on use of telephones and four were generated from qualitative studies, but none comprehensively reflect complexities of bridging nursing process and elements of nursing practice into use of telehealth. The purpose of this article is to present a review of existing conceptual models and frameworks, discuss predominant themes and features of these models, and present a comprehensive conceptual model for telehealth nursing practice synthesized from this literature for consideration and further development. This conceptual model illustrates characteristics of, and relationships between, dimensions of telehealth practice to guide research and knowledge development in provision of holistic person-centered care delivery to individuals by nurses through telehealth technologies. © The Author(s) 2015.

How do illness-anxious individuals process health-threatening information? A systematic review of evidence for the cognitive-behavioral model.

PubMed

Leonidou, Chrysanthi; Panayiotou, Georgia

2018-08-01

According to the cognitive-behavioral model, illness anxiety is developed and maintained through biased processing of health-threatening information and maladaptive responses to such information. This study is a systematic review of research that attempted to validate central tenets of the cognitive-behavioral model regarding etiological and maintenance mechanisms in illness anxiety. Sixty-two studies, including correlational and experimental designs, were identified through a systematic search of databases and were evaluated for their quality. Outcomes were synthesized following a qualitative thematic approach under categories of theoretically driven mechanisms derived from the cognitive-behavioral model: attention, memory and interpretation biases, perceived awareness and inaccuracy in perception of somatic sensations, negativity bias, emotion dysregulation, and behavioral avoidance. Findings partly support the cognitive-behavioral model, but several of its hypothetical mechanisms only receive weak support due to the scarcity of relevant studies. Directions for future research are suggested based on identified gaps in the existing literature. Copyright © 2018 Elsevier Inc. All rights reserved.

Disaster Reintegration Model: A Qualitative Analysis on Developing Korean Disaster Mental Health Support Model

PubMed Central

O’Donnell, Meaghan

2018-01-01

This study sought to describe the mental health problems experienced by Korean disaster survivors, using a qualitative research method to provide empirical resources for effective disaster mental health support in Korea. Participants were 16 adults or elderly adults who experienced one or more disasters at least 12 months ago recruited via theoretical sampling. Participants underwent in-depth individual interviews on their disaster experiences, which were recorded and transcribed for qualitative analysis, which followed Strauss and Corbin’s (1998) Grounded theory. After open coding, participants’ experiences were categorized into 130 codes, 43 sub-categories and 17 categories. The categories were further analyzed in a paradigm model, conditional model and the Disaster Reintegration Model, which proposed potentially effective mental health recovery strategies for disaster survivors, health providers and administrators. To provide effective assistance for mental health recovery of disaster survivors, both personal and public resilience should be promoted while considering both cultural and spiritual elements. PMID:29463030

Structure and mechanism of diet specialisation: testing models of individual variation in resource use with sea otters

USGS Publications Warehouse

Tinker, M. Tim; Guimarães, Paulo R.; Novak, Mark; Marquitti, Flavia Maria Darcie; Bodkin, James L.; Staedler, Michelle; Bentall, Gena B.; Estes, James A.

2012-01-01

Studies of consumer-resource interactions suggest that individual diet specialisation is empirically widespread and theoretically important to the organisation and dynamics of populations and communities. We used weighted networks to analyze the resource use by sea otters, testing three alternative models for how individual diet specialisation may arise. As expected, individual specialisation was absent when otter density was low, but increased at high-otter density. A high-density emergence of nested resource-use networks was consistent with the model assuming individuals share preference ranks. However, a density-dependent emergence of a non-nested modular network for ‘core’ resources was more consistent with the ‘competitive refuge’ model. Individuals from different diet modules showed predictable variation in rank-order prey preferences and handling times of core resources, further supporting the competitive refuge model. Our findings support a hierarchical organisation of diet specialisation and suggest individual use of core and marginal resources may be driven by different selective pressures.

A Systematic Process for Developing High Quality SaaS Cloud Services

NASA Astrophysics Data System (ADS)

La, Hyun Jung; Kim, Soo Dong

Software-as-a-Service (SaaS) is a type of cloud service which provides software functionality through Internet. Its benefits are well received in academia and industry. To fully utilize the benefits, there should be effective methodologies to support the development of SaaS services which provide high reusability and applicability. Conventional approaches such as object-oriented methods do not effectively support SaaS-specific engineering activities such as modeling common features, variability, and designing quality services. In this paper, we present a systematic process for developing high quality SaaS and highlight the essentiality of commonality and variability (C&V) modeling to maximize the reusability. We first define criteria for designing the process model and provide a theoretical foundation for SaaS; its meta-model and C&V model. We clarify the notion of commonality and variability in SaaS, and propose a SaaS development process which is accompanied with engineering instructions. Using the proposed process, SaaS services with high quality can be effectively developed.

Religiousness and hazardous alcohol use: a conditional indirect effects model.

PubMed

Jankowski, Peter J; Hardy, Sam A; Zamboanga, Byron L; Ham, Lindsay S

2013-08-01

The current study examined a conditional indirect effects model of the association between religiousness and adolescents' hazardous alcohol use. In doing so, we responded to the need to include both mediators and moderators, and the need for theoretically informed models when examining religiousness and adolescents' alcohol use. The sample consisted of 383 adolescents, aged 15-18, who completed an online questionnaire. Results of structural equation modeling supported the proposed model. Religiousness was indirectly associated with hazardous alcohol use through both positive alcohol expectancy outcomes and negative alcohol expectancy valuations. Significant moderating effects for alcohol expectancy valuations on the association between alcohol expectancies and alcohol use were also found. The effects for alcohol expectancy valuations confirm valuations as a distinct construct to that of alcohol expectancy outcomes, and offer support for the protective role of internalized religiousness on adolescents' hazardous alcohol use as a function of expectancy valuations. Copyright © 2013 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Sex Education, Public Opinion, and Pornography: A Conditional Process Analysis.

PubMed

Wright, Paul J

2018-05-10

This study assesses the relationship between pornography consumption and support for sex education in public schools among adults in the United States. Goals were theoretical and applied. At the theoretical level, conditional process analyses are needed to further evaluate the predictions of the primary theory applied to pornography and social influence, the sexual script acquisition, activation, application model ( 3 AM) of sexual media socialization. At the applied level, themes in pornography are most often associated with socialization outcomes that are a threat to the public health. In certain instances, however, pornography may socialize its users in ways that lead to health-promoting attitudes. An increased likelihood of support for sex education among youth may be one such example. Probabilistic national survey data gathered between 1988 and 2016 from 16 unique samples were utilized. A moderated-mediation path analysis indicated that pornography consumption was associated with support for sex education through more acceptance of teenage sex, but that this indirect effect (IE) was moderated by religiosity. Specifically, as religiosity decreased, the magnitude of the IE increased. These results are consistent with 3 AM tenets about the role of sexual scripts in mass media socialization and factors that increase the likelihood of sexual scripting effects.