Science.gov

Sample records for main theoretical framework

  1. An integrative nursing theoretical framework.

    PubMed

    Schmieding, N J

    1990-04-01

    The use of an integrative nursing theoretical framework for both clinical and administrative practice has recently been suggested. The author developed a theoretical framework which incorporates key concepts from the writings of Ida J. Orlando and Virginia Henderson and proposes it to be used as an integrative framework. The rationale for using a framework is discussed along with clinical and administrative examples of how to integrate concepts from the proposed framework. The reasons for using an integrative theoretical framework are that it: serves as a guide for both clinical and administrative decisions; forms the basis of the nursing philosophy; facilitates communication with patients and colleagues; helps identify congruent supporting theories and concepts; provides a basis for educational programmes; helps to differentiate nursing from non-nursing activities; and enhances nurse unity and self-esteem. The premise of the article is that benefits are derived from the use of a nursing theoretical framework because it provides a specific vision of nursing. PMID:2341692

  2. The Basic Theoretical Framework

    NASA Astrophysics Data System (ADS)

    Loeb, Abraham

    Cosmology is by now a mature experimental science. We are privileged to live at a time when the story of genesis (how the Universe started and developed) can be critically explored by direct observations. Looking deep into the Universe through powerful telescopes, we can see images of the Universe when it was younger because of the finite time it takes light to travel to us from distant sources. Existing data sets include an image of the Universe when it was 0.4 million years old (in the form of the cosmic microwave background), as well as images of individual galaxies when the Universe was older than a billion years. But there is a serious challenge: in between these two epochs was a period when the Universe was dark, stars had not yet formed, and the cosmic microwave background no longer traced the distribution of matter. And this is precisely the most interesting period, when the primordial soup evolved into the rich zoo of objects we now see. The observers are moving ahead along several fronts. The first involves the construction of large infrared telescopes on the ground and in space, that will provide us with new photos of the first galaxies. Current plans include ground-based telescopes which are 24-42 m in diameter, and NASA's successor to the Hubble Space Telescope, called the James Webb Space Telescope. In addition, several observational groups around the globe are constructing radio arrays that will be capable of mapping the three-dimensional distribution of cosmic hydrogen in the infant Universe. These arrays are aiming to detect the long-wavelength (redshifted 21-cm) radio emission from hydrogen atoms. The images from these antenna arrays will reveal how the non-uniform distribution of neutral hydrogen evolved with cosmic time and eventually was extinguished by the ultra-violet radiation from the first galaxies. Theoretical research has focused in recent years on predicting the expected signals for the above instruments and motivating these ambitious observational projects.

  3. Supervision from Six Theoretical Frameworks.

    ERIC Educational Resources Information Center

    Jensen, Jacquelyn W.

    Various theoretical frameworks approach teacher change differently. If teacher candidate supervisors adopt one form of supervision without understanding the assumptions and implications of other models, they risk being too narrow. To help supervisors in their role, an explanation of how a supervisor might intervene from six different perspectives…

  4. An e-Learning Theoretical Framework

    ERIC Educational Resources Information Center

    Aparicio, Manuela; Bacao, Fernando; Oliveira, Tiago

    2016-01-01

    E-learning systems have witnessed a usage and research increase in the past decade. This article presents the e-learning concepts ecosystem. It summarizes the various scopes on e-learning studies. Here we propose an e-learning theoretical framework. This theory framework is based upon three principal dimensions: users, technology, and services…

  5. An e-Learning Theoretical Framework

    ERIC Educational Resources Information Center

    Aparicio, Manuela; Bacao, Fernando; Oliveira, Tiago

    2016-01-01

    E-learning systems have witnessed a usage and research increase in the past decade. This article presents the e-learning concepts ecosystem. It summarizes the various scopes on e-learning studies. Here we propose an e-learning theoretical framework. This theory framework is based upon three principal dimensions: users, technology, and services…

  6. Learning Physical Domains: Toward a Theoretical Framework.

    ERIC Educational Resources Information Center

    Forbus, Kenneth D.; Gentner, Dedre

    People use and extend their knowledge of the physical world constantly. Understanding how this fluency is achieved would be an important milestone in understanding human learning and intelligence, as well as a useful guide for constructing machines that learn. This paper presents a theoretical framework that is being developed in an attempt to…

  7. Unifying Different Theories of Learning: Theoretical Framework and Empirical Evidence

    ERIC Educational Resources Information Center

    Phan, Huy Phuong

    2008-01-01

    The main aim of this research study was to test out a conceptual model encompassing the theoretical frameworks of achievement goals, study processing strategies, effort, and reflective thinking practice. In particular, it was postulated that the causal influences of achievement goals on academic performance are direct and indirect through study…

  8. Bayesian Decision Theoretical Framework for Clustering

    ERIC Educational Resources Information Center

    Chen, Mo

    2011-01-01

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

  9. Bayesian Decision Theoretical Framework for Clustering

    ERIC Educational Resources Information Center

    Chen, Mo

    2011-01-01

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

  10. A Theoretical Framework for Bilingual Special Education.

    ERIC Educational Resources Information Center

    Cummins, Jim

    1989-01-01

    A theoretical matrix for conceptualizing issues within bilingual special education is outlined. Issues addressed include the difficulty of distinguishing learning disabilities from second-language-learning problems, nondiscriminatory assessment of language and intellectual skills, effects of bilingual interactions at home and school, and…

  11. Toward a theoretical framework for interprofessional education.

    PubMed

    Barr, Hugh

    2013-01-01

    This paper searches for the antecedents of some of many diverse theoretical perspectives being brought to bear to understand interprofessional education (IPE) toward developing a coherent, compatible and inclusive frame of reference. Some of the sources cited are original, "leaving everything to play for" in applying them to IPE. Others apply one or more of those sources to interprofessional learning or the context in which it is delivered. Combining perspectives in this way is helpful insofar as it furthers coherence across disciplinary boundaries, but leaves the serious scholar to trace each back to its roots. Considerations of space preclude a definitive review of the ever-increasing repertoire of theoretical perspectives being introduced into IPE from anthropology education, psychology, sociology and other academic disciplines. This paper focuses on those theories which elucidate the learning process and the learning context. PMID:22747337

  12. Responsive space: Concept analysis and theoretical framework

    NASA Astrophysics Data System (ADS)

    Saleh, Joseph H.; Dubos, Gregory F.

    2009-08-01

    Customers' needs are dynamic and evolve in response to unfolding environmental uncertainties. The ability of a company or an industry to address these changing customers' needs in a timely and cost-effective way is a measure of its responsiveness. In the space industry, a systemic discrepancy exists between the time constants associated with the change of customers' needs, and the response time of the industry in delivering on-orbit solutions to these needs. There are important penalties associated with such delays, and space responsiveness is recognized as a strategic imperative in commercial competitive and military environments. In this paper, we provide a critical assessment of the literature on responsive space and introduce a new multi-disciplinary framework for thinking about and addressing issues of space responsiveness. Our framework advocates three levels of responsiveness: a global industry-wide responsiveness, a local stakeholder responsiveness, and an interactive or inter-stakeholder responsiveness. We introduce and motivate the use of "responsiveness maps" for multiple stakeholders. We then identify "levers of responsiveness": technical spacecraft- and launch-centric, as well as "soft" levers (e.g., acquisition policies) for improving the responsiveness of the space industry. Finally, we propose a series of research questions to aggressively tackle problems associated with space responsiveness.

  13. Consulting Course Design: Theoretical Frameworks and Pedagogical Strategies.

    ERIC Educational Resources Information Center

    Dallimore, Elise J.; Souza, Tasha J.

    2002-01-01

    Presents an approach to teaching a consulting course that uses instructional frameworks and a service learning perspective. Notes the course explores consulting by using theoretical frameworks for thinking about and conducting consulting activities. Discusses the consulting research assignment, the service learning assignment, and considers course…

  14. Multicultural Career Counseling: Theoretical Applications of the Systems Theory Framework

    ERIC Educational Resources Information Center

    Arthur, Nancy; McMahon, Mary

    2005-01-01

    Increasing recognition of cultural influences on career development requires expanded theoretical and practical perspectives. Theories of career development need to explicate views of culture and provide direction for career counseling with clients who are culturally diverse. The Systems Theory Framework (STF) is a theoretical foundation that…

  15. A Theoretical Framework for Physics Education Research: Modeling Student Thinking

    ERIC Educational Resources Information Center

    Redish, Edward F.

    2004-01-01

    Education is a goal-oriented field. But if we want to treat education scientifically so we can accumulate, evaluate, and refine what we learn, then we must develop a theoretical framework that is strongly rooted in objective observations and through which different theoretical models of student thinking can be compared. Much that is known in the…

  16. Exploring how globalization shapes education: methodology and theoretical framework

    NASA Astrophysics Data System (ADS)

    Pan, Su-Yan

    2010-06-01

    This is a commentary on some major issues raised in Carter and Dediwalage's "Globalisation and science education: The case of Sustainability by the bay" (this issue), particularly their methodology and theoretical framework for understanding how globalisation shapes education (including science education). While acknowledging the authors' contribution to the literature on globalisation and education, it questions the degree to which their analysis captures and explains how globalisation shapes science education, and examines how the research can be complemented by altering its methodology and expanding its theoretical framework.

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

    ERIC Educational Resources Information Center

    Ornek, Funda

    2008-01-01

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

  18. Educational Communities of Inquiry: Theoretical Framework, Research and Practice

    ERIC Educational Resources Information Center

    Akyol, Zehra; Garrison, D. Randy

    2013-01-01

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

  19. Dialogue: A Theoretical Framework for Distance Education Instructional Systems

    ERIC Educational Resources Information Center

    Gorsky, Paul; Caspi, Avner

    2005-01-01

    This paper presents a theoretical framework for viewing elements that comprise distance education instructional systems in terms of dialogue. It is assumed that learning is mediated by intrapersonal dialogue and facilitated by interpersonal dialogue. Every resource in a distance education instructional system (eg, instructor availability,…

  20. Internet Use and Cognitive Development: A Theoretical Framework

    ERIC Educational Resources Information Center

    Johnson, Genevieve

    2006-01-01

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

  1. Implicit Theoretical Leadership Frameworks of Higher Education Administrators.

    ERIC Educational Resources Information Center

    Lees, Kimberly; And Others

    Colleges and universities have a unique organizational culture that influences the decision-making processes used by leaders of higher education. This paper presents findings of a study that attempted to identify the theoretical frameworks that administrators of higher education use to guide their decision-making processes. The following…

  2. Internet Use and Cognitive Development: A Theoretical Framework

    ERIC Educational Resources Information Center

    Johnson, Genevieve

    2006-01-01

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

  3. Exploring How Globalization Shapes Education: Methodology and Theoretical Framework

    ERIC Educational Resources Information Center

    Pan, Su-Yan

    2010-01-01

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

  4. A Theoretical Framework towards Understanding of Emotional and Behavioural Difficulties

    ERIC Educational Resources Information Center

    Poulou, Maria S.

    2014-01-01

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

  5. Educational Communities of Inquiry: Theoretical Framework, Research and Practice

    ERIC Educational Resources Information Center

    Akyol, Zehra; Garrison, D. Randy

    2013-01-01

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

  6. Framework for a space shuttle main engine health monitoring system

    NASA Technical Reports Server (NTRS)

    Hawman, Michael W.; Galinaitis, William S.; Tulpule, Sharayu; Mattedi, Anita K.; Kamenetz, Jeffrey

    1990-01-01

    A framework developed for a health management system (HMS) which is directed at improving the safety of operation of the Space Shuttle Main Engine (SSME) is summarized. An emphasis was placed on near term technology through requirements to use existing SSME instrumentation and to demonstrate the HMS during SSME ground tests within five years. The HMS framework was developed through an analysis of SSME failure modes, fault detection algorithms, sensor technologies, and hardware architectures. A key feature of the HMS framework design is that a clear path from the ground test system to a flight HMS was maintained. Fault detection techniques based on time series, nonlinear regression, and clustering algorithms were developed and demonstrated on data from SSME ground test failures. The fault detection algorithms exhibited 100 percent detection of faults, had an extremely low false alarm rate, and were robust to sensor loss. These algorithms were incorporated into a hierarchical decision making strategy for overall assessment of SSME health. A preliminary design for a hardware architecture capable of supporting real time operation of the HMS functions was developed. Utilizing modular, commercial off-the-shelf components produced a reliable low cost design with the flexibility to incorporate advances in algorithm and sensor technology as they become available.

  7. Towards a Theoretical Framework of Heritage Language Literacy and Identity Processes

    ERIC Educational Resources Information Center

    Lo-Philip, Stephanie Wing-Yan

    2010-01-01

    Drawing mainly on Pierre Bourdieu's notions of symbolic capital, Bakhtin's concept of voice and heteroglossia in the novel, and Gee's theory of Discourses and the term third space as applied in education, I construct a theoretical framework for heritage language (HL) literacy and identity processes. I propose that HL literacy acquisition be viewed…

  8. A detection-theoretic framework for modeling informational masking

    PubMed Central

    Lutfi, Robert A.; Chang, An-Chieh; Stamas, Jacob; Gilbertson, Lynn

    2012-01-01

    There has been growing interest in recent years in masking that appears to have its origin at a central level of the auditory nervous system—so-called informational masking (IM). Masker uncertainty and target-masker similarity have been identified as the two major factors affecting IM; however, no theoretical framework currently exists that would give precise meaning to these terms necessary to evaluate their relative importance or model their effects. The present paper offers a first attempt at such a framework constructed within the doctrines of the theory of signal detection. PMID:22894307

  9. Levels of racism: a theoretic framework and a gardener's tale.

    PubMed Central

    Jones, C P

    2000-01-01

    The author presents a theoretic framework for understanding racism on 3 levels: institutionalized, personally mediated, and internalized. This framework is useful for raising new hypotheses about the basis of race-associated differences in health outcomes, as well as for designing effective interventions to eliminate those differences. She then presents an allegory about a gardener with 2 flower boxes, rich and poor soil, and red and pink flowers. This allegory illustrates the relationship between the 3 levels of racism and may guide our thinking about how to intervene to mitigate the impacts of racism on health. It may also serve as a tool for starting a national conversation on racism. PMID:10936998

  10. Regulatory framework in assisted reproductive technologies, relevance and main issues.

    PubMed

    Merlet, Françoise

    2009-01-01

    Assisted reproductive technologies (ART) have changed life for the past 25 years and many ethical and social issues have emerged following this new method of conception. In order to protect individuals against scientific and ethical abuses without inhibiting scientific progress, a specific legal framework is necessary. The first French law on Bioethics was voted after an extensive debate in 1994 then reviewed in 2004. This review previously scheduled every five years is currently being discussed. Legal provisions applying to ART are part of a large framework including the protection of the patients' rights and biomedical research. The key principles consist of respect for human life and ban on commercial practices of human body parts, eugenic practices and any kind of cloning. These key principles apply to ART. Donation is anonymous and free. Created in 2004, the Agence de la biomédecine is a government agency and one of the main tools of the French regulations. The missions focus on improving the quality and the safety of the management of ART. Evaluation of activities is available to all from the annual report. The agency represents the French competent authority for medical and scientific aspects of ART. Substantial differences in European legislations exist from the open-up "laissez faire" to the most restrictive one. As a consequence a large reproductive tourism has developed particularly for egg donation or surrogacy. The medical and ethical conditions of management of patients and donors represent the main critical points. In order to avoid ethical abuses, homogenization regarding the key principles is necessary in Europe. It is an opportunity to reassert that human body parts should not be a source of financial gain. PMID:20067901

  11. Toward a theoretical framework for trustworthy cyber sensing

    NASA Astrophysics Data System (ADS)

    Xu, Shouhuai

    2010-04-01

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

  12. Unsupervised image-set clustering using an information theoretic framework.

    PubMed

    Goldberger, Jacob; Gordon, Shiri; Greenspan, Hayit

    2006-02-01

    In this paper, we combine discrete and continuous image models with information-theoretic-based criteria for unsupervised hierarchical image-set clustering. The continuous image modeling is based on mixture of Gaussian densities. The unsupervised image-set clustering is based on a generalized version of a recently introduced information-theoretic principle, the information bottleneck principle. Images are clustered such that the mutual information between the clusters and the image content is maximally preserved. Experimental results demonstrate the performance of the proposed framework for image clustering on a large image set. Information theoretic tools are used to evaluate cluster quality. Particular emphasis is placed on the application of the clustering for efficient image search and retrieval. PMID:16479815

  13. Using Learning Principles as a Theoretical Framework for Instructional Consultations

    ERIC Educational Resources Information Center

    DiPietro, Michele; Norman, Marie

    2014-01-01

    Learning theory provides a powerful framework for analyzing instructional consultations and increasing their effectiveness. In this paper, the authors review the main tenets of learning theory, apply them to consultation scenarios, and present a complex case study to show how they can guide analysis and problem solving around challenging…

  14. Theoretical framework for estimating snow distribution through point measurements

    NASA Astrophysics Data System (ADS)

    Trujillo, E.; Lehning, M.

    2015-01-01

    In recent years, marked improvements in our knowledge of the statistical properties of the spatial distribution of snow properties have been achieved thanks to improvements in measuring technologies (e.g. LIDAR, TLS, and GPR). Despite of this, objective and quantitative frameworks for the evaluation of errors and extrapolations in snow measurements have been lacking. Here, we present a theoretical framework for quantitative evaluations of the uncertainty of point measurements of snow depth when used to represent the average depth over a profile section or an area. The error is defined as the expected value of the squared difference between the real mean of the profile/field and the sample mean from a limited number of measurements. The model is tested for one and two dimensional survey designs that range from a single measurement to an increasing number of regularly-spaced measurements. Using high-resolution (~1 m) LIDAR snow depths at two locations in Colorado, we show that the sample errors follow the theoretical behavior. Furthermore, we show how the determination of the spatial location of the measurements can be reduced to an optimization problem for the case of the predefined number of measurements, or to the designation of an acceptable uncertainty level to determine the total number of regularly-spaced measurements required to achieve such error. On this basis, a series of figures are presented that can be used to aid in the determination of the survey design under the conditions described, and under the assumption of prior knowledge of the spatial covariance/correlation properties. With this methodology, better objective survey designs can be accomplished, tailored to the specific applications for which the measurements are going to be used. The theoretical framework can be extended to other spatially distributed snow variables (e.g. SWE) whose statistical properties are comparable to those of snow depth.

  15. A Universal Operator Theoretic Framework for Quantum Fault Tolerance.

    NASA Astrophysics Data System (ADS)

    Gilbert, Gerald; Calderbank, Robert; Aggarwal, Vaneet; Hamrick, Michael; Weinstein, Yaakov

    2008-03-01

    We introduce a universal operator theoretic framework for quantum fault tolerance. This incorporates a top-down approach that implements a system-level criterion based on specification of the full system dynamics, applied at every level of error correction concatenation. This leads to more accurate determinations of error thresholds than could previously be obtained. The basis for the approach is the Quantum Computer Condition (QCC), an inequality governing the evolution of a quantum computer. In addition to more accurate determination of error threshold values, we show that the QCC provides a means to systematically determine optimality (or non-optimality) of different choices of error correction coding and error avoidance strategies. This is possible because, as we show, all known coding schemes are actually special cases of the QCC. We demonstrate this by introducing a new, operator theoretic form of entanglement assisted quantum error correction.

  16. A theoretical framework for patient-reported outcome measures.

    PubMed

    McClimans, Leah

    2010-06-01

    Patient-reported outcome measures (PROMs) are increasingly used to assess multiple facets of healthcare, including effectiveness, side effects of treatment, symptoms, health care needs, quality of care, and the evaluation of health care options. There are thousands of these measures and yet there is very little discussion of their theoretical underpinnings. In her 2008 Presidential address to the Society for Quality of Life Research (ISOQoL), Professor Donna Lamping challenged researchers to grapple with the theoretical issues that arise from these measures. In this paper, I attempt to do so by arguing for an analogy between PROMs and Hans-Georg Gadamer's logic of question and answer. While researchers readily admit that the constructs involved in PROMs are imperfectly understood and lack a gold standard, they often ignore the consequences of this fact. Gadamer's work on questions and their importance to philosophical hermeneutics helps to show that the questions researchers ask about such constructs are also imperfectly understood. I argue that these questions should not be standardized, and I instead propose a theoretical framework that understands PROMs as posing genuine questions to respondents--questions that are open to reinterpretation. PMID:20526684

  17. Sociomateriality: a theoretical framework for studying distributed medical education.

    PubMed

    MacLeod, Anna; Kits, Olga; Whelan, Emma; Fournier, Cathy; Wilson, Keith; Power, Gregory; Mann, Karen; Tummons, Jonathan; Brown, Peggy Alexiadis

    2015-11-01

    Distributed medical education (DME) is a type of distance learning in which students participate in medical education from diverse geographic locations using Web conferencing, videoconferencing, e-learning, and similar tools. DME is becoming increasingly widespread in North America and around the world.Although relatively new to medical education, distance learning has a long history in the broader field of education and a related body of literature that speaks to the importance of engaging in rigorous and theoretically informed studies of distance learning. The existing DME literature is helpful, but it has been largely descriptive and lacks a critical "lens"-that is, a theoretical perspective from which to rigorously conceptualize and interrogate DME's social (relationships, people) and material (technologies, tools) aspects.The authors describe DME and theories about distance learning and show that such theories focus on social, pedagogical, and cognitive considerations without adequately taking into account material factors. They address this gap by proposing sociomateriality as a theoretical framework allowing researchers and educators to study DME and (1) understand and consider previously obscured actors, infrastructure, and other factors that, on the surface, seem unrelated and even unimportant; (2) see clearly how the social and material components of learning are intertwined in fluid, messy, and often uncertain ways; and (3) perhaps think differently, even in ways that disrupt traditional approaches, as they explore DME. The authors conclude that DME brings with it substantial investments of social and material resources, and therefore needs careful study, using approaches that embrace its complexity. PMID:25830536

  18. Epistemologically authentic inquiry in schools: A theoretical framework for evaluating inquiry tasks

    NASA Astrophysics Data System (ADS)

    Chinn, Clark A.; Malhotra, Betina A.

    2002-03-01

    A main goal of science education is to help students learn to reason scientifically. A main way to facilitate learning is to engage students in inquiry activities such as conducting experiments. This article presents a theoretical framework for evaluating inquiry tasks in terms of how similar they are to authentic science. The framework helps identify the respects in which these reasoning tasks are similar to and different from real scientific research. The framework is based on a recent theory of reasoning, models-of-data theory. We argue that inquiry tasks commonly used in schools evoke reasoning processes that are qualitatively different from the processes employed in real scientific inquiry. Moreover, school reasoning tasks appear to be based on an epistemology that differs from the epistemology of authentic science. Inquiry tasks developed by researchers have increasingly captured features of authentic science, but further improvement is still possible. We conclude with a discussion of the implications of our analysis for research, assessment, and instruction.

  19. Choosing a theoretical framework to guide HESI exit examination research.

    PubMed

    Nibert, Ainslie T; Adamson, Carolyn; Young, Anne; Lauchner, Kathryn A; Britt, Robin B; Hinds, Mary Newman

    2006-08-01

    This article responds to issues raised in 2004 by Spurlock and Hanks, who interpreted data that were presented in four published studies describing the validity of the Health Education Systems, Inc. (HESI) Exit Examination. The argument for using classical testing theory as the preferred theoretical framework to a clinical disease detection model is advanced. While the Spurlock and Hanks article promotes a philosophical bias against the establishment of progression policies within schools of nursing, this article offers another assessment of the merits of detecting at-risk students so timely remediation can occur prior to administration of the National Council Licensure Examination for Registered Nurses (NCLEX-RN). From data presented in the four validity studies, the HESI Exit Examination was reported to be 96.36% to 98.30% accurate in predicting NCLEX-RN success, and those original findings are reaffirmed. PMID:16915987

  20. Development of a theoretical framework for analyzing cerebrospinal fluid dynamics

    PubMed Central

    Cohen, Benjamin; Voorhees, Abram; Vedel, Søren; Wei, Timothy

    2009-01-01

    Background To date hydrocephalus researchers acknowledge the need for rigorous but utilitarian fluid mechanics understanding and methodologies in studying normal and hydrocephalic intracranial dynamics. Pressure volume models and electric circuit analogs introduced pressure into volume conservation; but control volume analysis enforces independent conditions on pressure and volume. Previously, utilization of clinical measurements has been limited to understanding of the relative amplitude and timing of flow, volume and pressure waveforms; qualitative approaches without a clear framework for meaningful quantitative comparison. Methods Control volume analysis is presented to introduce the reader to the theoretical background of this foundational fluid mechanics technique for application to general control volumes. This approach is able to directly incorporate the diverse measurements obtained by clinicians to better elucidate intracranial dynamics and progression to disorder. Results Several examples of meaningful intracranial control volumes and the particular measurement sets needed for the analysis are discussed. Conclusion Control volume analysis provides a framework to guide the type and location of measurements and also a way to interpret the resulting data within a fundamental fluid physics analysis. PMID:19772652

  1. A Game Theoretic Framework for Analyzing Re-Identification Risk

    PubMed Central

    Wan, Zhiyu; Vorobeychik, Yevgeniy; Xia, Weiyi; Clayton, Ellen Wright; Kantarcioglu, Murat; Ganta, Ranjit; Heatherly, Raymond; Malin, Bradley A.

    2015-01-01

    Given the potential wealth of insights in personal data the big databases can provide, many organizations aim to share data while protecting privacy by sharing de-identified data, but are concerned because various demonstrations show such data can be re-identified. Yet these investigations focus on how attacks can be perpetrated, not the likelihood they will be realized. This paper introduces a game theoretic framework that enables a publisher to balance re-identification risk with the value of sharing data, leveraging a natural assumption that a recipient only attempts re-identification if its potential gains outweigh the costs. We apply the framework to a real case study, where the value of the data to the publisher is the actual grant funding dollar amounts from a national sponsor and the re-identification gain of the recipient is the fine paid to a regulator for violation of federal privacy rules. There are three notable findings: 1) it is possible to achieve zero risk, in that the recipient never gains from re-identification, while sharing almost as much data as the optimal solution that allows for a small amount of risk; 2) the zero-risk solution enables sharing much more data than a commonly invoked de-identification policy of the U.S. Health Insurance Portability and Accountability Act (HIPAA); and 3) a sensitivity analysis demonstrates these findings are robust to order-of-magnitude changes in player losses and gains. In combination, these findings provide support that such a framework can enable pragmatic policy decisions about de-identified data sharing. PMID:25807380

  2. A game theoretic framework for analyzing re-identification risk.

    PubMed

    Wan, Zhiyu; Vorobeychik, Yevgeniy; Xia, Weiyi; Clayton, Ellen Wright; Kantarcioglu, Murat; Ganta, Ranjit; Heatherly, Raymond; Malin, Bradley A

    2015-01-01

    Given the potential wealth of insights in personal data the big databases can provide, many organizations aim to share data while protecting privacy by sharing de-identified data, but are concerned because various demonstrations show such data can be re-identified. Yet these investigations focus on how attacks can be perpetrated, not the likelihood they will be realized. This paper introduces a game theoretic framework that enables a publisher to balance re-identification risk with the value of sharing data, leveraging a natural assumption that a recipient only attempts re-identification if its potential gains outweigh the costs. We apply the framework to a real case study, where the value of the data to the publisher is the actual grant funding dollar amounts from a national sponsor and the re-identification gain of the recipient is the fine paid to a regulator for violation of federal privacy rules. There are three notable findings: 1) it is possible to achieve zero risk, in that the recipient never gains from re-identification, while sharing almost as much data as the optimal solution that allows for a small amount of risk; 2) the zero-risk solution enables sharing much more data than a commonly invoked de-identification policy of the U.S. Health Insurance Portability and Accountability Act (HIPAA); and 3) a sensitivity analysis demonstrates these findings are robust to order-of-magnitude changes in player losses and gains. In combination, these findings provide support that such a framework can enable pragmatic policy decisions about de-identified data sharing. PMID:25807380

  3. Vaccine Hesitancy: Clarifying a Theoretical Framework for an Ambiguous Notion

    PubMed Central

    Peretti-Watel, Patrick; Larson, Heidi J; Ward, Jeremy K.; Schulz, William S; Verger, Pierre

    2015-01-01

    Today, according to many public health experts, public confidence in vaccines is waning. The term “vaccine hesitancy” (VH) is increasingly used to describe the spread of such vaccine reluctance. But VH is an ambiguous notion and its theoretical background appears uncertain. To clarify this concept, we first review the current definitions of VH in the public health literature and examine its most prominent characteristics. VH has been defined as a set of beliefs, attitudes, or behaviours, or some combination of them, shared by a large and heterogeneous portion of the population and including people who exhibit reluctant conformism (they may either decline a vaccine, delay it or accept it despite their doubts) and vaccine-specific behaviours. Secondly, we underline some of the ambiguities of this notion and argue that it is more a catchall category than a real concept. We also call into question the usefulness of understanding VH as an intermediate position along a continuum ranging from anti-vaccine to pro-vaccine attitudes, and we discuss its qualification as a belief, attitude or behaviour. Thirdly, we propose a theoretical framework, based on previous literature and taking into account some major structural features of contemporary societies, that considers VH as a kind of decision-making process that depends on people’s level of commitment to healthism/risk culture and on their level of confidence in the health authorities and mainstream medicine. PMID:25789201

  4. A theoretical framework for jamming in confluent biological tissues

    NASA Astrophysics Data System (ADS)

    Manning, M. Lisa

    2015-03-01

    For important biological functions such as wound healing, embryonic development, and cancer tumorogenesis, cells must initially rearrange and move over relatively large distances, like a liquid. Subsequently, these same tissues must undergo buckling and support shear stresses, like a solid. Our work suggests that biological tissues can accommodate these disparate requirements because the tissues are close to glass or jamming transition. While recent self propelled particle models generically predict a glass/jamming transition that is driven by packing density φ and happens at some critical φc less than unity, many biological tissues that are confluent with no gaps between cells appear to undergo a jamming transition at a constant density (φ = 1). I will discuss a new theoretical framework for predicting energy barriers and rates of cell migration in 2D tissue monolayers, and show that this model predicts a novel type of rigidity transition, which takes place at constant φ = 1 and depends only on single cell properties such as cell-cell adhesion, cortical tension and cell elasticity. This model additionally predicts that an experimentally observable parameter, the ratio between a cell's perimeter and the square root of its cross-sectional area, attains a specific, critical value at the jamming transition. We show that this prediction is precisely realized in primary epithelial cultures from human patients, with implications for asthma pathology.

  5. The Dolinar Receiver in an Information Theoretic Framework

    NASA Technical Reports Server (NTRS)

    Erkmen, Baris I.; Birnbaum, Kevin M.; Moision, Bruce E.; Dolinar, Samuel J.

    2011-01-01

    Optical communication at the quantum limit requires that measurements on the optical field be maximally informative, but devising physical measurements that accomplish this objective has proven challenging. The Dolinar receiver exemplifies a rare instance of success in distinguishing between two coherent states: an adaptive local oscillator is mixed with the signal prior to photodetection, which yields an error probability that meets the Helstrom lower bound with equality. Here we apply the same local-oscillator-based architecture with aninformation-theoretic optimization criterion. We begin with analysis of this receiver in a general framework for an arbitrary coherent-state modulation alphabet, and then we concentrate on two relevant examples. First, we study a binary antipodal alphabet and show that the Dolinar receiver's feedback function not only minimizes the probability of error, but also maximizes the mutual information. Next, we study ternary modulation consistingof antipodal coherent states and the vacuum state. We derive an analytic expression for a near-optimal local oscillator feedback function, and, via simulation, we determine its photon information efficiency (PIE). We provide the PIE versus dimensional information efficiency (DIE) trade-off curve and show that this modulation and the our receiver combination performs universally better than (generalized) on-off keying plus photoncounting, although, the advantage asymptotically vanishes as the bits-per-photon diverges towards infinity.

  6. Modeling and forecasting health expectancy: theoretical framework and application.

    PubMed

    Majer, Istvan M; Stevens, Ralph; Nusselder, Wilma J; Mackenbach, Johan P; van Baal, Pieter H M

    2013-04-01

    Life expectancy continues to grow in most Western countries; however, a major remaining question is whether longer life expectancy will be associated with more or fewer life years spent with poor health. Therefore, complementing forecasts of life expectancy with forecasts of health expectancies is useful. To forecast health expectancy, an extension of the stochastic extrapolative models developed for forecasting total life expectancy could be applied, but instead of projecting total mortality and using regular life tables, one could project transition probabilities between health states simultaneously and use multistate life table methods. In this article, we present a theoretical framework for a multistate life table model in which the transition probabilities depend on age and calendar time. The goal of our study is to describe a model that projects transition probabilities by the Lee-Carter method, and to illustrate how it can be used to forecast future health expectancy with prediction intervals around the estimates. We applied the method to data on the Dutch population aged 55 and older, and projected transition probabilities until 2030 to obtain forecasts of life expectancy, disability-free life expectancy, and probability of compression of disability. PMID:23104206

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

    PubMed Central

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

    2015-01-01

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

  8. A New Replicator: A theoretical framework for analysing replication

    PubMed Central

    2010-01-01

    Background Replicators are the crucial entities in evolution. The notion of a replicator, however, is far less exact than the weight of its importance. Without identifying and classifying multiplying entities exactly, their dynamics cannot be determined appropriately. Therefore, it is importance to decide the nature and characteristics of any multiplying entity, in a detailed and formal way. Results Replication is basically an autocatalytic process which enables us to rest on the notions of formal chemistry. This statement has major implications. Simple autocatalytic cycle intermediates are considered as non-informational replicators. A consequence of which is that any autocatalytically multiplying entity is a replicator, be it simple or overly complex (even nests). A stricter definition refers to entities which can inherit acquired changes (informational replicators). Simple autocatalytic molecules (and nests) are excluded from this group. However, in turn, any entity possessing copiable information is to be named a replicator, even multicellular organisms. In order to deal with the situation, an abstract, formal framework is presented, which allows the proper identification of various types of replicators. This sheds light on the old problem of the units and levels of selection and evolution. A hierarchical classification for the partition of the replicator-continuum is provided where specific replicators are nested within more general ones. The classification should be able to be successfully applied to known replicators and also to future candidates. Conclusion This paper redefines the concept of the replicator from a bottom-up theoretical approach. The formal definition and the abstract models presented can distinguish between among all possible replicator types, based on their quantity of variable and heritable information. This allows for the exact identification of various replicator types and their underlying dynamics. The most important claim is that replication, in general, is basically autocatalysis, with a specific defined environment and selective force. A replicator is not valid unless its working environment, and the selective force to which it is subject, is specified. PMID:20219099

  9. Toward an Instructional Philosophy: "A Theoretical Framework for Teaching and Training at Salman Bin Abdulaziz University (SAU)"

    ERIC Educational Resources Information Center

    Qandile, Yasine A.; Al-Qasim, Wajeeh Q.

    2014-01-01

    The purpose of this study is to construct a clear instructional philosophy for Salman bin Abdulaziz University as a fundamental basis for teaching and training as well as a theoretical framework for curriculum design and development. The study attempts to answer the main questions about pertaining to the basic structure of contemporary higher…

  10. A Theoretical Framework for the Studio as a Learning Environment

    ERIC Educational Resources Information Center

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

    2013-01-01

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

  11. A Theoretical Framework for the Studio as a Learning Environment

    ERIC Educational Resources Information Center

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

    2013-01-01

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

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

    ERIC Educational Resources Information Center

    Palmer, Zsuzsanna Bacsa

    2013-01-01

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

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

    PubMed Central

    2012-01-01

    Background An integrative theoretical framework, developed for cross-disciplinary implementation and other behaviour change research, has been applied across a wide range of clinical situations. This study tests the validity of this framework. Methods Validity was investigated by behavioural experts sorting 112 unique theoretical constructs using closed and open sort tasks. The extent of replication was tested by Discriminant Content Validation and Fuzzy Cluster Analysis. Results There was good support for a refinement of the framework comprising 14 domains of theoretical constructs (average silhouette value 0.29): ‘Knowledge’, ‘Skills’, ‘Social/Professional Role and Identity’, ‘Beliefs about Capabilities’, ‘Optimism’, ‘Beliefs about Consequences’, ‘Reinforcement’, ‘Intentions’, ‘Goals’, ‘Memory, Attention and Decision Processes’, ‘Environmental Context and Resources’, ‘Social Influences’, ‘Emotions’, and ‘Behavioural Regulation’. Conclusions The refined Theoretical Domains Framework has a strengthened empirical base and provides a method for theoretically assessing implementation problems, as well as professional and other health-related behaviours as a basis for intervention development. PMID:22530986

  14. A Theoretical Framework for the Study of Adult Cognitive Plasticity

    ERIC Educational Resources Information Center

    Lovden, Martin; Backman, Lars; Lindenberger, Ulman; Schaefer, Sabine; Schmiedek, Florian

    2010-01-01

    Does plasticity contribute to adult cognitive development, and if so, in what ways? The vague and overused concept of plasticity makes these controversial questions difficult to answer. In this article, we refine the notion of adult cognitive plasticity and sharpen its conceptual distinctiveness. According to our framework, adult cognitive…

  15. Primary Teachers' Attitudes toward Science: A New Theoretical Framework

    ERIC Educational Resources Information Center

    van Aalderen-Smeets, Sandra I.; Walma van der Molen, Juliette H.; Asma, Lieke J. F.

    2012-01-01

    Attention to the attitudes of preservice and inservice primary teachers toward science is of fundamental importance to research on primary science education. However, progress in this field of research has been slow due to the poor definition and conceptualization of the construct of primary teachers' attitude toward science. This poor theoretical…

  16. Multiple Intelligent Mentors Instructing Collaboratively (MIMIC): Developing a Theoretical Framework.

    ERIC Educational Resources Information Center

    Baylor, Amy

    This paper describes preliminary work on "Multiple Intelligent Mentors Instructing Collaboratively" (MIMIC), an intelligent Web-based agent environment for learning instructional design. The focus is on developing theoretical foundations of instructional design and instructional theory that form the foundation for systems development. In the…

  17. Potential benefits of remote sensing: Theoretical framework and empirical estimate

    NASA Technical Reports Server (NTRS)

    Eisgruber, L. M.

    1972-01-01

    A theoretical framwork is outlined for estimating social returns from research and application of remote sensing. The approximate dollar magnitude is given of a particular application of remote sensing, namely estimates of corn production, soybeans, and wheat. Finally, some comments are made on the limitations of this procedure and on the implications of results.

  18. A Type-Theoretic Framework for Certified Model Transformations

    NASA Astrophysics Data System (ADS)

    Calegari, Daniel; Luna, Carlos; Szasz, Nora; Tasistro, Álvaro

    We present a framework based on the Calculus of Inductive Constructions (CIC) and its associated tool the Coq proof assistant to allow certification of model transformations in the context of Model-Driven Engineering (MDE). The approached is based on a semi-automatic translation process from metamodels, models and transformations of the MDE technical space into types, propositions and functions of the CIC technical space. We describe this translation and illustrate its use in a standard case study.

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

    ERIC Educational Resources Information Center

    Hess, Juliet

    2015-01-01

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

  20. Towards Developing a Theoretical Framework for Measuring Public Sector Managers' Career Success

    ERIC Educational Resources Information Center

    Rasdi, Roziah Mohd; Ismail, Maimunah; Uli, Jegak; Noah, Sidek Mohd

    2009-01-01

    Purpose: The purpose of this paper is to develop a theoretical framework for measuring public sector managers' career success. Design/methodology/approach: The theoretical foundation used in this study is social cognitive career theory. To conduct a literature search, several keywords were identified, i.e. career success, objective and subjective…

  1. Towards Developing a Theoretical Framework for Measuring Public Sector Managers' Career Success

    ERIC Educational Resources Information Center

    Rasdi, Roziah Mohd; Ismail, Maimunah; Uli, Jegak; Noah, Sidek Mohd

    2009-01-01

    Purpose: The purpose of this paper is to develop a theoretical framework for measuring public sector managers' career success. Design/methodology/approach: The theoretical foundation used in this study is social cognitive career theory. To conduct a literature search, several keywords were identified, i.e. career success, objective and subjective…

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

    ERIC Educational Resources Information Center

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

    2014-01-01

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

  3. Interprofessional learning in acute care: developing a theoretical framework.

    PubMed

    Lewis, Robin

    2012-04-01

    There are a number of adult learning theories that have been used to inform IPE delivery (e.g. Kolb's theory of experiential learning), and one of the most important to emerge in recent times has been the contact theory or contact hypothesis, which looks at the outcomes when two differing groups of health care professionals are brought together. The team responsible for the development of an acute care IPE programme called Student Management of Acute illness Recognition and Treatment (SMART(TM)) set out to incorporate the most up to date educational theory into the programme. Following an extensive review of the literature, it was decided to adopt a blended theoretical approach, involving a combination of 'contact theory' and 'scaffolding', supported by interprofessional facilitation. It was clear that there were a number of enabling factors that could be incorporated into any IPE programme. These were the educational setting, group characteristics (group size, balance and stability), quality of IPE facilitation and opportunities for informal learning. Although the contact theory provides us with a better understanding of interprofessional groups, an understanding of how the organised contact of different professional groups of students helps to reduce intergroup prejudice and improve intergroup relations is still required. PMID:21531487

  4. A theoretical framework for research into environmental education

    NASA Astrophysics Data System (ADS)

    Aho, Leena

    1984-06-01

    The essential question in environmental education is the individual's relationship to his environment, including both that part of his environment which is natural and that part which is man-made. The nature of this relationship is manifested in the way in which the individual acts with regard to his environment and by what choices and decisions he makes in order to come to terms with it. The crucial factors in these decisions are his values, which at the same time represent his cognitive, socio-emotional and ethical development. As an interdisciplinary subject, environmental education draws attention to the technique of examining matters from a variety of viewpoints. Since the consequences of man's decisions regarding his environment are apparent both in the sphere of human life and in the world of nature, these decisions involve ecological and economic, social, political, aesthetic and ethical considerations. Environmental education contains both cognitive and affective aspects, the association between which is examined on the basis of the theoretical premises established in this paper.

  5. Emergent Writing in Preschoolers: Preliminary Evidence for a Theoretical Framework

    PubMed Central

    Puranik, Cynthia S.; Lonigan, Christopher J.

    2014-01-01

    Researchers and educators use the term emergent literacy to refer to a broad set of skills and attitudes that serve as foundational skills for acquiring success in later reading and writing; however, models of emergent literacy have generally focused on reading and reading-related behaviors. Hence, the primary aim of this study was to articulate and evaluate a theoretical model of the components of emergent writing. Alternative models of the structure of individual and developmental differences of emergent writing and writing-related skills were examined in 372 preschool children who ranged in age from 3- to 5-years using confirmatory factor analysis. Results from a confirmatory factor analysis provide evidence that these emergent writing skills are best described by three correlated but distinct factors, (a) Conceptual Knowledge, (b) Procedural Knowledge, and (c) Generative Knowledge. Evidence that these three emergent writing factors show different patterns of relations to emergent literacy constructs is presented. Implications for understanding the development of writing and assessment of early writing skills are discussed. PMID:25316955

  6. Human rights in patient care: a theoretical and practical framework.

    PubMed

    Cohen, Jonathan; Ezer, Tamar

    2013-01-01

    The concept of "human rights in patient care" refers to the application of human rights principles to the context of patient care. It provides a principled alternative to the growing discourse of "patients' rights" that has evolved in response to widespread and severe human rights violations in health settings. Unlike "patients' rights," which is rooted in a consumer framework, this concept derives from inherent human dignity and neutrally applies universal, legally recognized human rights principles, protecting both patients and providers and admitting of limitations that can be justified by human rights norms. It recognizes the interrelation between patient and provider rights, particularly in contexts where providers face simultaneous obligations to patients and the state ("dual loyalty") and may be pressured to abet human rights violations. The human rights lens provides a means to examine systemic issues and state responsibility. Human rights principles that apply to patient care include both the right to the highest attainable standard of health, which covers both positive and negative guarantees in respect of health, as well as civil and political rights ranging from the patient's right to be free from torture and inhumane treatment to liberty and security of person. They also focus attention on the right of socially excluded groups to be free from discrimination in the delivery of health care. Critical rights relevant to providers include freedom of association and the enjoyment of decent work conditions. Some, but not all, of these human rights correspond to rights that have been articulated in "patients' rights" charters. Complementary to—but distinct from—bioethics, human rights in patient care carry legal force and can be applied through judicial action. They also provide a powerful language to articulate and mobilize around justice concerns, and to engage in advocacy through the media and political negotiation. As "patients' rights" movements and charters grow in popularity, it is important to link patient rights back to human rights standards and processes that are grounded in international law and consensus. PMID:24421170

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

    PubMed

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

    2014-09-01

    Biodynamic feedthrough (BDFT) is a complex phenomenon, which has been studied for several decades. However, there is little consensus on how to approach the BDFT problem in terms of definitions, nomenclature, and mathematical descriptions. In this paper, a framework for biodynamic feedthrough analysis is presented. The goal of this framework is two-fold. First, it provides some common ground between the seemingly large range of different approaches existing in the BDFT literature. Second, the framework itself allows for gaining new insights into BDFT phenomena. It will be shown how relevant signals can be obtained from measurement, how different BDFT dynamics can be derived from them, and how these different dynamics are related. Using the framework, BDFT can be dissected into several dynamical relationships, each relevant in understanding BDFT phenomena in more detail. The presentation of the BDFT framework is divided into two parts. This paper, Part I, addresses the theoretical foundations of the framework. Part II, which is also published in this issue, addresses the validation of the framework. The work is presented in two separate papers to allow for a detailed discussion of both the framework's theoretical background and its validation. PMID:24816627

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

    PubMed

    Barnes-Holmes, Dermot; Hussey, Ian

    2016-02-01

    The functional-cognitive meta-theoretical framework has been offered as a conceptual basis for facilitating greater communication and cooperation between the functional/behavioural and cognitive traditions within psychology, thus leading to benefits for both scientific communities. The current article is written from the perspective of two functional researchers, who are also proponents of the functional-cognitive framework, and attended the "Building Bridges between the Functional and Cognitive Traditions" meeting at Ghent University in the summer of 2014. The article commences with a brief summary of the functional approach to theory, followed by our reflections upon the functional-cognitive framework in light of that meeting. In doing so, we offer three ways in which the framework could be clarified: (a) effective communication between the two traditions is likely to be found at the level of behavioural observations rather than effects or theory, (b) not all behavioural observations will be deemed to be of mutual interest to both traditions, and (c) observations of mutual interest will be those that serve to elaborate and extend existing theorising in the functional and/or cognitive traditions. The article concludes with a summary of what we perceive to be the strengths and weaknesses of the framework, and a suggestion that there is a need to determine if the framework is meta-theoretical or is in fact a third theoretical approach to doing psychological science. PMID:25877882

  9. NLPIR: A Theoretical Framework for Applying Natural Language Processing to Information Retrieval.

    ERIC Educational Resources Information Center

    Zhou, Lina; Zhang, Dongsong

    2003-01-01

    Proposes a theoretical framework called NLPIR that integrates natural language processing (NLP) into information retrieval (IR) based on the assumption that there exists representation distance between queries and documents. Discusses problems in traditional keyword-based IR, including relevance, and describes some existing NLP techniques.…

  10. A Theoretical Framework for Building Online Communities of Practice with Social Networking Tools

    ERIC Educational Resources Information Center

    Gunawardena, Charlotte N.; Hermans, Mary Beth; Sanchez, Damien; Richmond, Carol; Bohley, Maribeth; Tuttle, Rebekah

    2009-01-01

    This paper proposes a theoretical framework as a foundation for building online communities of practice when a suite of social networking applications referred to as collective intelligence tools are utilized to develop a product or solutions to a problem. Drawing on recent developments in Web 2.0 tools, research on communities of practice and…

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

    ERIC Educational Resources Information Center

    Quinn, Frances; Pegg, John; Panizzon, Debra

    2009-01-01

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

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

    ERIC Educational Resources Information Center

    Quinn, Frances; Pegg, John; Panizzon, Debra

    2009-01-01

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

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

    ERIC Educational Resources Information Center

    Lind, Sophie E.

    2010-01-01

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

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

    ERIC Educational Resources Information Center

    Lind, Sophie E.

    2010-01-01

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

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

    ERIC Educational Resources Information Center

    Grant, Cynthia; Osanloo, Azadeh

    2014-01-01

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

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

    ERIC Educational Resources Information Center

    Johnson, Genevieve Marie

    2006-01-01

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

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

    ERIC Educational Resources Information Center

    Han, Hyemin

    2014-01-01

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

  18. Language Learning Strategies--The Theoretical Framework and Some Suggestions for Learner Training Practice

    ERIC Educational Resources Information Center

    Liang, Ting

    2009-01-01

    Research in the field of second language learning indicates that proper use of language learning strategies leads to the improvement of overall Second Language (L2) or Foreign Language (FL) proficiency as well as specific language skills. This essay firstly attempts to build a theoretical framework of learning strategies theories by clarifying the…

  19. Applying the Grossman et al. Theoretical Framework: The Case of Reading

    ERIC Educational Resources Information Center

    Kucan, Linda; Palincsar, Annemarie Sullivan; Busse, Tracy; Heisey, Natalie; Klingelhofer, Rachel; Rimbey, Michelle; Schutz, Kristine

    2011-01-01

    Background/Context: This article describes the application of the theoretical framework proposed by Grossman and her colleagues to a research effort focusing on text-based discussion as a context for comprehension instruction. According to Grossman and her colleagues, a useful way to consider the teaching of complex practices to candidates is to…

  20. Theoretical Framework for the Appalachian Collaborative Center for Learning, Assessment, and Instruction in Mathematics (ACCLAIM).

    ERIC Educational Resources Information Center

    Ohio Univ., Athens. Appalachian Collaborative Center for Learning, Assessment, and Instruction in Mathematics.

    This statement abstracts the theoretical framework for the Appalachian Collaborative Center for Learning, Assessment, and Instruction in Mathematics (ACCLAIM). ACCLAIM's mission is the cultivation of indigenous leadership capacity for the improvement of school mathematics in rural places. The mission addresses local organizational ability to (1)…

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

    ERIC Educational Resources Information Center

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

    2013-01-01

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

  2. NLPIR: A Theoretical Framework for Applying Natural Language Processing to Information Retrieval.

    ERIC Educational Resources Information Center

    Zhou, Lina; Zhang, Dongsong

    2003-01-01

    Proposes a theoretical framework called NLPIR that integrates natural language processing (NLP) into information retrieval (IR) based on the assumption that there exists representation distance between queries and documents. Discusses problems in traditional keyword-based IR, including relevance, and describes some existing NLP techniques.…

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

    ERIC Educational Resources Information Center

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

    2014-01-01

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

  4. In Search of Theoretical Framework: A Case Study of Chinese Mothers' Experiences in Immigration and Education

    ERIC Educational Resources Information Center

    Chen, Shujun

    2010-01-01

    This paper seeks to develop a theoretical framework that is applicable to research on recent immigrant Chinese mothers in the United States. Although Black, Chicana, and transnational feminist epistemologies exist in previous scholarship, there is no comparable discourse in the study of Chinese mothers' experiences in the United States. In this…

  5. A Theoretical Framework to Guide the Re-Engineering of Technology Education

    ERIC Educational Resources Information Center

    Kelley, Todd; Kellam, Nadia

    2009-01-01

    Before leaders in technology education are able to identify a theoretical framework upon which a curriculum is to stand, they must first grapple with two opposing views of the purpose of technology education--education for all learners or career/technical education. Dakers (2006) identifies two opposing philosophies that can serve as a framework…

  6. Compassion Fatigue as a Theoretical Framework to Help Understand Burnout among Special Education Teachers

    ERIC Educational Resources Information Center

    Hoffman, Shari; Palladino, John M.; Barnett, Jeffery

    2007-01-01

    Compassion fatigue is a theoretical framework researchers have applied to helping professions other than teaching. The purpose of this report is to propose the use of this theory to better understand the prevalent rates of special education teachers' exit from the profession often labeled as burnout. A qualitative study with six middle school…

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

    ERIC Educational Resources Information Center

    Koh, Kyungwon

    2011-01-01

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

  8. Understanding the Role of Numeracy in Health: Proposed Theoretical Framework and Practical Insights

    ERIC Educational Resources Information Center

    Lipkus, Isaac M.; Peters, Ellen

    2009-01-01

    Numeracy--that is, how facile people are with mathematical concepts and their applications--is gaining importance in medical decision making and risk communication. This article proposes six critical functions of health numeracy. These functions are integrated into a theoretical framework on health numeracy that has implications for risk…

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

    ERIC Educational Resources Information Center

    Koh, Kyungwon

    2011-01-01

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

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

    ERIC Educational Resources Information Center

    McIlveen, Peter

    2007-01-01

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

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

    PubMed

    Petrini, Carlo

    2015-01-01

    The "Framework for the Ethical Conduct of Public Health Initiatives", developed by Public Health Ontario, is a practical guide for assessing the ethical implications of evidence-generating public health initiatives, whether research or non-research activities, involving people, their biological materials or their personal information. The Framework is useful not only to those responsible for determining the ethical acceptability of an initiative, but also to investigators planning new public health initiatives. It is informed by a theoretical approach that draws on widely shared bioethical principles. Two considerations emerge from both the theoretical framework and its practical application: the line between practice and research is often blurred; public health ethics and biomedical research ethics are based on the same common heritage of values. PMID:26241514

  12. 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.

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

    PubMed

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

    2015-05-01

    A field-widened Michelson interferometer (FWMI) is developed to act as the spectral discriminator in high-spectral-resolution lidar (HSRL). This realization is motivated by the wide-angle Michelson interferometer (WAMI) which has been used broadly in the atmospheric wind and temperature detection. This paper describes an independent theoretical framework about the application of the FWMI in HSRL for the first time. In the framework, the operation principles and application requirements of the FWMI are discussed in comparison with that of the WAMI. Theoretical foundations for designing this type of interferometer are introduced based on these comparisons. Moreover, a general performance estimation model for the FWMI is established, which can provide common guidelines for the performance budget and evaluation of the FWMI in the both design and operation stages. Examples incorporating many practical imperfections or conditions that may degrade the performance of the FWMI are given to illustrate the implementation of the modeling. This theoretical framework presents a complete and powerful tool for solving most of theoretical or engineering problems encountered in the FWMI application, including the designing, parameter calibration, prior performance budget, posterior performance estimation, and so on. It will be a valuable contribution to the lidar community to develop a new generation of HSRLs based on the FWMI spectroscopic filter. PMID:25969300

  14. Analysis of poetic literature using B. F. Skinner's theoretical framework from verbal behavior

    PubMed Central

    Luke, Nicole M.

    2003-01-01

    This paper examines Skinner's work on verbal behavior in the context of literature as a particular class of written verbal behavior. It looks at contemporary literary theory and analysis and the contributions that Skinner's theoretical framework can make. Two diverse examples of poetic literature are chosen and analyzed following Skinner's framework, examining the dynamic interplay between the writer and reader that take place within the bounds of the work presented. It is concluded that Skinner's hypotheses about verbal behavior and the functional approach to understanding it have much to offer literary theorists in their efforts to understand literary works and should be more carefully examined.

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

    PubMed

    Hutchings, Maggie; Scammell, Janet; Quinney, Anne

    2013-09-01

    While there is growing evidence of theoretical perspectives adopted in interprofessional education, learning theories tend to foreground the individual, focusing on psycho-social aspects of individual differences and professional identity to the detriment of considering social-structural factors at work in social practices. Conversely socially situated practice is criticised for being context-specific, making it difficult to draw generalisable conclusions for improving interprofessional education. This article builds on a theoretical framework derived from earlier research, drawing on the dynamics of Dewey's experiential learning theory and Archer's critical realist social theory, to make a case for a meta-theoretical framework enabling social-constructivist and situated learning theories to be interlinked and integrated through praxis and reflexivity. Our current analysis is grounded in an interprofessional curriculum initiative mediated by a virtual community peopled by health and social care users. Student perceptions, captured through quantitative and qualitative data, suggest three major disruptive themes, creating opportunities for congruence and disjuncture and generating a model of zones of interlinked praxis associated with professional differences and identity, pedagogic strategies and technology-mediated approaches. This model contributes to a framework for understanding the complexity of interprofessional learning and offers bridges between individual and structural factors for engaging with the enablements and constraints at work in communities of practice and networks for interprofessional education. PMID:23679676

  16. Framework for a U.S. Geological Survey Hydrologic Climate-Response Program in Maine

    USGS Publications Warehouse

    Hodgkins, Glenn A.; Lent, Robert M.; Dudley, Robert W.; Schalk, Charles W.

    2009-01-01

    It is important to monitor hydrologic systems in the United States that could change dramatically over the short term as a result of climate change. Many ecological effects of climate change can be understood only if hydrologic data networks are in place. Because of its humid, temperate climate and its substantial annual snowpack, Maine's seasonal water cycle is sensitive to air temperature changes (Hodgkins and others, 2003). Monitoring of relevant hydrologic data would provide important baseline information against which future climate change can be measured. A series of recent investigations by the U.S. Geological Survey (USGS) has documented changes in several components of the water cycle, including earlier snowmelt runoff in Maine during the last 30 to 40 years (Hodgkins and others, 2003), earlier lake- and river-ice breakups (Hodgkins and others, 2002; Hodgkins and others, 2005), and a denser and thinner late-winter snowpack (Hodgkins and Dudley, 2006). Snowmelt runoff timing was measured as the date, each year, by which half of the total winter-spring streamflow passed a streamflow-gaging station. Historical snowmelt runoff timing for the Piscataquis River in central Maine is shown in figure 1 as an example. Results of climate projections input to hydrologic models indicate that hydrologic trends, such as earlier spring snowmelt runoff, are expected to continue into the future (Hayhoe and others, 2007). These trends could affect species at the southern edge of their range in Maine, such as Atlantic salmon and Canada lynx, and may also affect availability of water for human use. This fact sheet describes the framework of a hydrologic climate-response program that would improve understanding of the effects of future climate change in Maine.

  17. Framework for a U.S. Geological Survey Hydrologic Climate-Response Program in Maine

    USGS Publications Warehouse

    Hodgkins, Glenn A.; Lent, Robert M.; Dudley, Robert W.; Schalk, Charles W.

    2009-01-01

    This report presents a framework for a U.S. Geological Survey (USGS) hydrologic climate-response program designed to provide early warning of changes in the seasonal water cycle of Maine. Climate-related hydrologic changes on Maine's rivers and lakes in the winter and spring during the last century are well documented, and several river and lake variables have been shown to be sensitive to air-temperature changes. Monitoring of relevant hydrologic data would provide important baseline information against which future climate change can be measured. The framework of the hydrologic climate-response program presented here consists of four major parts: (1) identifying homogeneous climate-response regions; (2) identifying hydrologic components and key variables of those components that would be included in a hydrologic climate-response data network - as an example, streamflow has been identified as a primary component, with a key variable of streamflow being winter-spring streamflow timing; the data network would be created by maintaining existing USGS data-collection stations and establishing new ones to fill data gaps; (3) regularly updating historical trends of hydrologic data network variables; and (4) establishing basins for process-based studies. Components proposed for inclusion in the hydrologic climate-response data network have at least one key variable for which substantial historical data are available. The proposed components are streamflow, lake ice, river ice, snowpack, and groundwater. The proposed key variables of each component have extensive historical data at multiple sites and are expected to be responsive to climate change in the next few decades. These variables are also important for human water use and (or) ecosystem function. Maine would be divided into seven climate-response regions that follow major river-basin boundaries (basins subdivided to hydrologic units with 8-digit codes or larger) and have relatively homogeneous climates. Key hydrologic variables within each climate-response region would be analyzed regularly to maintain up-to-date analyses of year-to-year variability, decadal variability, and longer term trends. Finally, one basin in each climate-response region would be identified for process-based hydrologic and ecological studies.

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

    NASA Astrophysics Data System (ADS)

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

    2015-04-01

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

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

    PubMed

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

    2015-01-01

    Spatial heterogeneity of the hydraulic properties of geological porous formations leads to erratically shaped solute clouds, thus increasing the edge area of the solute body and augmenting the dilution rate. In this study, we provide a theoretical framework to quantify dilution of a non-reactive solute within a steady state flow as affected by the spatial variability of the hydraulic conductivity. Embracing the Lagrangian concentration framework, we obtain explicit semi-analytical expressions for the dilution index as a function of the structural parameters of the random hydraulic conductivity field, under the assumptions of uniform-in-the-average flow, small injection source and weak-to-mild heterogeneity. Results show how the dilution enhancement of the solute cloud is strongly dependent on both the statistical anisotropy ratio and the heterogeneity level of the porous medium. The explicit semi-analytical solution also captures the temporal evolution of the dilution rate; for the early- and late-time limits, the proposed solution recovers previous results from the literature, while at intermediate times it reflects the increasing interplay between large-scale advection and local-scale dispersion. The performance of the theoretical framework is verified with high resolution numerical results and successfully tested against the Cape Cod field data. PMID:25795562

  20. The developmental niche: a theoretical framework for analyzing the household production of health.

    PubMed

    Harkness, S; Super, C M

    1994-01-01

    Recent efforts to promote child survival and development internationally have focused new attention on the importance of the household as a mediator of both environmental risks and programmatic interventions to promote better health. In this paper, we introduce a theoretical framework, the 'developmental niche,' derived from studies of children's behavior and development in different cultural contexts, as a tool for analyzing the household production of health. The developmental niche is conceptualized in terms of three basic components: (1) the physical and social settings of the child's everyday life; (2) culturally regulated customs of child care and child rearing; and (3) the psychology of the caretakers. The relevance of each of these components to the household production of health is illustrated through examples from research in several cultures, including Malaysia, Kenya, Bangladesh, India, and the U.S. Further discussion centers on three corollaries of the developmental niche framework that point to the interactive relationships among the three components, between the niche and the larger environment, and between the niche and the child (or any individual seen from a developmental perspective). It is suggested that this approach is useful for identifying and collecting relevant information on household-level factors that affect health outcomes, and thus for organizing more effective interventions. At a theoretical level, the developmental niche framework also facilitates understanding processes of mutual adaptation between the individual and the environment as they are filtered through the constraints of household settings, customs and caretaker psychologies. PMID:8140448

  1. Towards culturally relevant classroom science: a theoretical framework focusing on traditional plant healing

    NASA Astrophysics Data System (ADS)

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

    2014-03-01

    A theoretical framework is an important component of a research study. It grounds the study and guides the methodological design. It also forms a reference point for the interpretation of the research findings. This paper conceptually examines the process of constructing a multi-focal theoretical lens for guiding studies that aim to accommodate local culture in science classrooms. A multi-focal approach is adopted because the integration of indigenous knowledge and modern classroom science is complex. The central argument in this paper is that a multi-focal lens accommodates the multifaceted nature of integrating indigenous knowledge and western oriented classroom science. The objective of the paper, therefore, is to construct a theoretical framework that can be used to guide and inform the integration of indigenous knowledge and western science at classroom science level. The traditional plant healing form of indigenous knowledge is used as a case study. The paper is important for raising the complexities, tensions and dilemmas inherent in the design and implementation of indigenous knowledge-science integrated curricula. An understanding of the issues raised will pave the way towards achieving culturally relevant classroom science.

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

    PubMed Central

    2014-01-01

    Shift work and overtime have been implicated as important work-related risk factors for cardiovascular disease (CVD). Many firefighters who contractually work on a 24-hr work schedule, often do overtime (additional 24-hr shifts) which can result in working multiple, consecutive 24-hr shifts. Very little research has been conducted on firefighters at work that examines the impact of performing consecutive 24-hr shifts on cardiovascular physiology. Also, there have been no standard field methods for assessing in firefighters the cardiovascular changes that result from 24-hr shifts, what we call “cardiovascular strain”. The objective of this study, as the first step toward elucidating the role of very long (> 48 hrs) shifts in the development of CVD in firefighters, is to develop and describe a theoretical framework for studying cardiovascular strain in firefighters on very long shifts (i.e., > 2 consecutive 24-hr shifts). The developed theoretical framework was built on an extensive literature review, our recently completed studies with firefighters in Southern California, e-mail and discussions with several firefighters on their experiences of consecutive shifts, and our recently conducted feasibility study in a small group of firefighters of several ambulatory cardiovascular strain biomarkers (heart rate, heart rate variability, blood pressure, salivary cortisol, and salivary C-reactive protein). The theoretical framework developed in this study will facilitate future field studies on consecutive 24-hr shifts and cardiovascular health in firefighters. Also it will increase our understanding of the mechanisms by which shift work or long work hours can affect CVD, particularly through CVD biological risk factors, and thereby inform policy about sustainable work and rest schedules for firefighters. PMID:24602344

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

    PubMed

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

    2014-01-01

    Shift work and overtime have been implicated as important work-related risk factors for cardiovascular disease (CVD). Many firefighters who contractually work on a 24-hr work schedule, often do overtime (additional 24-hr shifts) which can result in working multiple, consecutive 24-hr shifts. Very little research has been conducted on firefighters at work that examines the impact of performing consecutive 24-hr shifts on cardiovascular physiology. Also, there have been no standard field methods for assessing in firefighters the cardiovascular changes that result from 24-hr shifts, what we call "cardiovascular strain". The objective of this study, as the first step toward elucidating the role of very long (> 48 hrs) shifts in the development of CVD in firefighters, is to develop and describe a theoretical framework for studying cardiovascular strain in firefighters on very long shifts (i.e., > 2 consecutive 24-hr shifts). The developed theoretical framework was built on an extensive literature review, our recently completed studies with firefighters in Southern California, e-mail and discussions with several firefighters on their experiences of consecutive shifts, and our recently conducted feasibility study in a small group of firefighters of several ambulatory cardiovascular strain biomarkers (heart rate, heart rate variability, blood pressure, salivary cortisol, and salivary C-reactive protein). The theoretical framework developed in this study will facilitate future field studies on consecutive 24-hr shifts and cardiovascular health in firefighters. Also it will increase our understanding of the mechanisms by which shift work or long work hours can affect CVD, particularly through CVD biological risk factors, and thereby inform policy about sustainable work and rest schedules for firefighters. PMID:24602344

  4. Variance within homogeneous phytoplankton populations, I: Theoretical framework for interpreting histograms.

    PubMed

    Campbell, J W; Yentsch, C M

    1989-09-01

    A framework is presented for interpreting frequency distributions of volume or fluorescence as measured by a flow cytometer on homogeneous phytoplankton populations. The framework, based on both laboratory experience and theoretical concepts, is illustrated with the use of a simulation model. Asynchronous, synchronous, and phased populations were simulated, with constant and variable growth patterns over the cell cycle. Though simulations produced a wide variety of histogram shapes, including multimodal distributions, the primary difference between asynchronous and synchronous/phased distributions lies in their temporal variation. Histograms that are constant in time indicate asynchronous populations; when populations are not asynchronous, their histogram shapes vary with a periodicity on the same time scale as the cell cycle. A probability density function for the case of asynchronous populations with a constant growth rate is derived. When fitted to simulated histograms this two-parameter density function yields estimates of the two parameters: mean and variance of cell volume (or mass) at age 0. PMID:2776575

  5. A theoretical framework of ecological phase transitions for characterizing tree-grass dynamics.

    PubMed

    Li, Bai-Lian

    2002-01-01

    This paper describes a theoretical framework of ecological phase transitions for modeling tree-grass dynamics and analyzing the shifts or phase transitions from one vegetation structure to another in the southern Texas landscape. This framework implements the integration of percolation theory, fractal geometry and phase transition theory as a method for modeling the spatial patterns of tree-grass dynamics, and nonlinear Markov non-equilibrium thermodynamic stability theory as a method for characterizing temporal tree-grass dynamics and phase transition. An historical sequence of aerial photographs at a Prosopis-thornscrub savanna parkland site in southern Texas was used to determine the parameters of the models. The preliminary analytical result accords well with current understanding and field survey of vegetation dynamics in the southern Texas landscape. The potential of such approaches and other relevant theories such as self-organized criticality and synergetics to vegetation dynamics is also discussed. PMID:12211328

  6. A new theoretical framework for modeling respiratory protection based on the beta distribution.

    PubMed

    Klausner, Ziv; Fattal, Eyal

    2014-08-01

    The problem of modeling respiratory protection is well known and has been dealt with extensively in the literature. Often the efficiency of respiratory protection is quantified in terms of penetration, defined as the proportion of an ambient contaminant concentration that penetrates the respiratory protection equipment. Typically, the penetration modeling framework in the literature is based on the assumption that penetration measurements follow the lognormal distribution. However, the analysis in this study leads to the conclusion that the lognormal assumption is not always valid, making it less adequate for analyzing respiratory protection measurements. This work presents a formulation of the problem from first principles, leading to a stochastic differential equation whose solution is the probability density function of the beta distribution. The data of respiratory protection experiments were reexamined, and indeed the beta distribution was found to provide the data a better fit than the lognormal. We conclude with a suggestion for a new theoretical framework for modeling respiratory protection. PMID:24942054

  7. A second gradient theoretical framework for hierarchical multiscale modeling of materials

    SciTech Connect

    Luscher, Darby J; Bronkhorst, Curt A; Mc Dowell, David L

    2009-01-01

    A theoretical framework for the hierarchical multiscale modeling of inelastic response of heterogeneous materials has been presented. Within this multiscale framework, the second gradient is used as a non local kinematic link between the response of a material point at the coarse scale and the response of a neighborhood of material points at the fine scale. Kinematic consistency between these scales results in specific requirements for constraints on the fluctuation field. The wryness tensor serves as a second-order measure of strain. The nature of the second-order strain induces anti-symmetry in the first order stress at the coarse scale. The multiscale ISV constitutive theory is couched in the coarse scale intermediate configuration, from which an important new concept in scale transitions emerges, namely scale invariance of dissipation. Finally, a strategy for developing meaningful kinematic ISVs and the proper free energy functions and evolution kinetics is presented.

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

    PubMed

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

    2015-03-01

    Multi-agency coordination represents a significant challenge in emergency management. The need for liaison officers working in strategic level emergency operations centres to play organizational boundary spanning roles within multi-agency coordination arrangements that are enacted in complex and dynamic emergency response scenarios creates significant research and practical challenges. The aim of the paper is to address a gap in the literature regarding the concept of multi-agency coordination from a human-environment interaction perspective. We present a theoretical framework for facilitating multi-agency coordination in emergency management that is grounded in human factors and ergonomics using the methodology of core-task analysis. As a result we believe the framework will enable liaison officers to cope more efficiently within the work domain. In addition, we provide suggestions for extending the theory of core-task analysis to an alternate high reliability environment. PMID:25480001

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

    PubMed

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

    2014-10-01

    Due to its high prevalence, chronic nature, potential complications, and self-management challenges for patients, diabetes presents significant health education and support issues. We developed and pilot-tested a virtual community for adults with type 2 diabetes to promote self-management education and provide social support. Although digital-based programs such as virtual environments can address significant barriers to reaching patients (i.e., child care, transportation, location), they must be strongly grounded in a theoretical basis to be well-developed and effective. In this article, we discuss how we synthesized behavioral and virtual environment theoretical frameworks to guide the development of SLIDES (Second Life Impacts Diabetes Education and Support). PMID:24451083

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

    NASA Astrophysics Data System (ADS)

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

    2013-07-01

    We analyze our method of teaching with primary historical sources within the context of theoretical frameworks for the role of history in teaching mathematics developed by Barbin, Fried, Jahnke, Jankvist, and Kjeldsen and Blomhøj, and more generally from the perspective of Sfard's theory of learning as communication. We present case studies for two of our guided student modules that are built around sequences of primary sources and are intended for learning core curricular material, one on logical implication, the other on the concept of a group. Additionally, we propose some conclusions about the advantages and challenges of using primary sources in teaching mathematics.

  11. Phylogenetic Framework and Molecular Signatures for the Main Clades of the Phylum Actinobacteria

    PubMed Central

    Gao, Beile

    2012-01-01

    Summary: The phylum Actinobacteria harbors many important human pathogens and also provides one of the richest sources of natural products, including numerous antibiotics and other compounds of biotechnological interest. Thus, a reliable phylogeny of this large phylum and the means to accurately identify its different constituent groups are of much interest. Detailed phylogenetic and comparative analyses of >150 actinobacterial genomes reported here form the basis for achieving these objectives. In phylogenetic trees based upon 35 conserved proteins, most of the main groups of Actinobacteria as well as a number of their superageneric clades are resolved. We also describe large numbers of molecular markers consisting of conserved signature indels in protein sequences and whole proteins that are specific for either all Actinobacteria or their different clades (viz., orders, families, genera, and subgenera) at various taxonomic levels. These signatures independently support the existence of different phylogenetic clades, and based upon them, it is now possible to delimit the phylum Actinobacteria (excluding Coriobacteriia) and most of its major groups in clear molecular terms. The species distribution patterns of these markers also provide important information regarding the interrelationships among different main orders of Actinobacteria. The identified molecular markers, in addition to enabling the development of a stable and reliable phylogenetic framework for this phylum, also provide novel and powerful means for the identification of different groups of Actinobacteria in diverse environments. Genetic and biochemical studies on these Actinobacteria-specific markers should lead to the discovery of novel biochemical and/or other properties that are unique to different groups of Actinobacteria. PMID:22390973

  12. Accuracy of theoretical calculations of the main parameters of the F2-layer of the daytime ionosphere

    NASA Astrophysics Data System (ADS)

    Pavlov, A. V.; Sitnov, Iu. S.

    1985-10-01

    Pavlov's (1984) method is used to determine the relative errors (due to errors in measuring the input parameters of the model) in theoretical calculations of the main parameters of the daytime F2-layer under quiet conditions. The parameters calculated are the height of the F2-layer maximum and the electron density.

  13. Graph theoretic framework based cooperative control and estimation of multiple UAVs for target tracking

    NASA Astrophysics Data System (ADS)

    Ahmed, Mousumi

    Designing the control technique for nonlinear dynamic systems is a significant challenge. Approaches to designing a nonlinear controller are studied and an extensive study on backstepping based technique is performed in this research with the purpose of tracking a moving target autonomously. Our main motivation is to explore the controller for cooperative and coordinating unmanned vehicles in a target tracking application. To start with, a general theoretical framework for target tracking is studied and a controller in three dimensional environment for a single UAV is designed. This research is primarily focused on finding a generalized method which can be applied to track almost any reference trajectory. The backstepping technique is employed to derive the controller for a simplified UAV kinematic model. This controller can compute three autopilot modes i.e. velocity, ground heading (or course angle), and flight path angle for tracking the unmanned vehicle. Numerical implementation is performed in MATLAB with the assumption of having perfect and full state information of the target to investigate the accuracy of the proposed controller. This controller is then frozen for the multi-vehicle problem. Distributed or decentralized cooperative control is discussed in the context of multi-agent systems. A consensus based cooperative control is studied; such consensus based control problem can be viewed from the algebraic graph theory concepts. The communication structure between the UAVs is represented by the dynamic graph where UAVs are represented by the nodes and the communication links are represented by the edges. The previously designed controller is augmented to account for the group to obtain consensus based on their communication. A theoretical development of the controller for the cooperative group of UAVs is presented and the simulation results for different communication topologies are shown. This research also investigates the cases where the communication topology switches to a different topology over particular time instants. Lyapunov analysis is performed to show stability in all cases. Another important aspect of this dissertation research is to implement the controller for the case, where perfect or full state information is not available. This necessitates the design of an estimator to estimate the system state. A nonlinear estimator, Extended Kalman Filter (EKF) is first developed for target tracking with a single UAV. The uncertainties involved with the measurement model and dynamics model are considered as zero mean Gaussian noises with some known covariances. The measurements of the full state of the target are not available and only the range, elevation, and azimuth angle are available from an onboard seeker sensor. A separate EKF is designed to estimate the UAV's own state where the state measurement is available through on-board sensors. The controller computes the three control commands based on the estimated states of target and its own states. Estimation based control laws is also implemented for colored noise measurement uncertainties, and the controller performance is shown with the simulation results. The estimation based control approach is then extended for the cooperative target tracking case. The target information is available to the network and a separate estimator is used to estimate target states. All of the UAVs in the network apply the same control law and the only difference is that each UAV updates the commands according to their connection. The simulation is performed for both cases of fixed and time varying communication topology. Monte Carlo simulation is also performed with different sample noises to investigate the performance of the estimator. The proposed technique is shown to be simple and robust to noisy environments.

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

    PubMed

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

    2015-12-01

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

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

    ERIC Educational Resources Information Center

    Styres, Sandra D.; Zinga, Dawn M.

    2013-01-01

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

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

    ERIC Educational Resources Information Center

    Styres, Sandra D.; Zinga, Dawn M.

    2013-01-01

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

  17. Patterns of Control over the Teaching-Studying-Learning Process and Classrooms as Complex Dynamic Environments: A Theoretical Framework

    ERIC Educational Resources Information Center

    Harjunen, Elina

    2012-01-01

    In this theoretical paper the role of power in classroom interactions is examined in terms of a dominance continuum to advance a theoretical framework justifying the emergence of three ways of distributing power when it comes to dealing with the control over the teaching-studying-learning (TSL) "pattern of teacher domination," "pattern of…

  18. Patterns of Control over the Teaching-Studying-Learning Process and Classrooms as Complex Dynamic Environments: A Theoretical Framework

    ERIC Educational Resources Information Center

    Harjunen, Elina

    2012-01-01

    In this theoretical paper the role of power in classroom interactions is examined in terms of a dominance continuum to advance a theoretical framework justifying the emergence of three ways of distributing power when it comes to dealing with the control over the teaching-studying-learning (TSL) "pattern of teacher domination," "pattern of…

  19. Theoretical Framework for the Assessment of Uncertainties in Snow Depth Measurements

    NASA Astrophysics Data System (ADS)

    Trujillo, E.; Lehning, M.

    2014-12-01

    In recent years, marked improvements in our knowledge of the statistical properties of the spatial distribution of snow properties have been achieved thanks to improvements in measuring technologies (e.g., LIDAR, TLS, and GPR). Despite of this, objective and quantitative frameworks for the evaluation of uncertainties in snow measurements have been lacking. Here, we present a theoretical framework for quantitative evaluations of the uncertainty of point measurements of snow depth when used to represent the average depth over a profile section or an area. We define the error as the expected value of the squared difference between the real mean of the profile/field and the sample mean from a limited number of measurements. The model is tested for one and two dimensional survey designs that range from a single measurement to an increasing number of regularly-spaced measurements. Using high-resolution (~ 1m) LIDAR snow depths at three locations in Colorado, we show that the sample errors follow the theoretical behavior. Furthermore, we show how the determination of the spatial location of the measurements can be reduced to an optimization problem for the case of a predefined number of measurements, or to the designation of an acceptable uncertainty level to determine the total number of regularly-spaced measurements required to achieve such error. On this basis, a series of figures are presented that can be used to aid in the determination of the survey design under the conditions described, and under the assumption of prior knowledge of the spatial covariance/correlation properties. With this methodology, better objective survey designs can be accomplished, tailored to the specific applications for which the measurements are going to be used. Although we discuss the proposed methodology in the context of snow depth, the theoretical framework can be extended to other spatially distributed snow variables (e.g., SWE and/or snow depth) or hydrologic variables (e.g., soil moisture) whose statistical properties can be compared to those of snow depth. Applications of the methodology will be discussed, such as the selection of the location of snow/meteorological stations in mountain environments or survey design to be able to capture watershed scale means.

  20. Stratigraphical framework of basaltic lavas in Torres Syncline main valley, southern Parana-Etendeka Volcanic Province

    NASA Astrophysics Data System (ADS)

    Rossetti, Lucas M.; Lima, Evandro F.; Waichel, Breno L.; Scherer, Claiton M.; Barreto, Carla J.

    2014-12-01

    The Paraná-Etendeka Volcanic Province records the volcanism of the Early Cretaceous that precedes the fragmentation of the South-Gondwana supercontinent. Traditionally, investigations of these rocks prioritized the acquisition of geochemical and isotopic data, considering the volcanic stack as a monotonous succession of tabular flows. Torres Syncline is a tectonic structure located in southern Brazil and where the Parana-Etendeka basalts are well preserved. This work provides a detailed analysis of lithofacies and facies architecture, integrated to petrographic and geochemical data. We identified seven distinct lithofacies grouped into four facies associations related to different flow morphologies. The basaltic lava flows in the area can be divided into two contrasting units: Unit I - pahoehoe flow fields; and Unit II - simple rubbly flows. The first unit is build up by innumerous pahoehoe lava flows that cover the sandstones of Botucatu Formation. These flows occur as sheet pahoehoe, compound pahoehoe, and ponded lavas morphologies. Compound lavas are olivine-phyric basalts with intergranular pyroxenes. In ponded lavas and cores of sheet flows coarse plagioclase-phyric basalts are common. The first pahoehoe lavas are more primitive with higher contents of MgO. The emplacement of compound pahoehoe flows is related to low volume eruptions, while sheet lavas were emplaced during sustained eruptions. In contrast, Unit II is formed by thick simple rubbly lavas, characterized by a massive core and a brecciated/rubbly top. Petrographically these flows are characterized by plagioclase-phyric to aphyric basalts with high density of plagioclase crystals in the matrix. Chemically they are more differentiated lavas, and the emplacement is related to sustained high effusion rate eruptions. Both units are low TiO2 and have geochemical characteristics of Gramado magma type. The Torres Syncline main valley has a similar evolution when compared to other Large Igneous Provinces, with compound flows at the base and simple flows in the upper portions. The detailed field work allied with petrography and geochemical data are extremely important to identify heterogeneities inside the volcanic pile and allows the construction of a detailed lithostratigraphical framework.

  1. Characterization of Meso-Habitat Framework from Orthophotographies. Application to the Drome River Main STEM (france)

    NASA Astrophysics Data System (ADS)

    Wiederkehr, E.; Dufour, S.; Piégay, H.

    2010-12-01

    According to the Water Framework Directive (WFD), “good ecological status” of all aquatic environments should be achieved by 2015. To validate this objective, new methodological tools are needed to evaluate river status and to target actions at regional scales. Amongst them, the assessment of physical condition of rivers is a critical issue. Because field measurement campaigns are a long and tedious and often do not provide homogeneous data throughout the network, the potential of orthophotographies to describe river physical characters is explored. In this contribution, we focused on aquatic meso-habitats, exploring new methods for characterising them at a large network scale using 50 cm resolution imagery now available for the entire French territory. We made a series of tests on a 25 km-long reach of the downstream Drôme River (France) to extract valuable information, validate methodological procedure and create indicators of aquatic habitat patterns. Firstly, we characterized the habitat structure synthetically by extracting information (e.g., mean radiometric values, texture index) on a set of spatial units of 10 m long. From this data set, we analysed the longitudinal pattern of different parameters to highlight spatial structures, notably the pool-riffle sequences, but also characterize the local and reach-scaled heterogeneity. Secondly, an automatic procedure has been developed to detect meso-habitats (riffle, pool, gravel bench, lentic/lotic channels) within the low flow channel using an object-oriented method and determine their main geometrical and radiometric characters (mean, median, majority, minority or standard deviation for each canal - Red, Green, Blue -). A factorial discriminant analysis has been performed on a set of known features (410 polygons) to establish a discriminant model allowing mapping habitat features at a reach scale Validation procedure shows about 90% of objects are well classified. From this map, new metrics were extracted to characterize the meso-habitats (facies frequency and geometrical characters). This information has then been summerized by homogeneous geomorphic reaches or fluvial pattern types (braided, meandering, straight-embanked homogeneous reaches) which are in fact a specific clustering of the previous homogeneous geomorphic reaches. These reaches were identified from other geomorphic information extracted on spatial units of 250 m long (ratio of the surface water / active channel, width of the active channel, sinuosity index and confinement index) and Pettitt test for segmentation. The data provided open challenging issues for scientific studies allowing studying space-time variability of meso-habitats at a regional network scale. Such data shall also be useful for managers to assess and monitor habitat quality following the implementation of the WFD.

  2. Applications of a unifying theoretical and computational framework to multiphase geophysical systems

    NASA Astrophysics Data System (ADS)

    Bergantz, George; Dufek, Joseph

    2004-11-01

    Emergent, multi-scale, multiphase processes dictate the fundamental template for many geophysical systems. Examples include accretion and differentiation of the early Earth, surface processes on Earth and other planets, space-planet interactions and volcanic eruptions. We will review canonical geophysical examples and exemplify the application of particle-turbulence interaction models appropriate for a variety of applications. Of special interest is representing the dilute-to-dense transition in a common theoretical framework, as well as the segregation of particles by vortical structures. We will describe our hybrid Eulerian-Lagrangian technique, and demonstrate how both descriptions of multiphase flow contribute to the fundamental time-dependence of natural systems, and are revealed in the ancient geological record.

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

    PubMed

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

    2015-08-01

    The tight bond between grounded theory (GT) and symbolic interactionism (SI) is well known within the qualitative health research field. We aimed to disentangle this connection through critical reflection on the conditions under which it might add value as an underpinning to studies outside the GT tradition. Drawing on an examination of the central tenets of SI, we illustrate with a field study using interpretive description as methodology how SI can be applied as a theoretical lens through which layers of socially constructed meaning can help surface the subjective world of patients. We demonstrate how SI can function as a powerful framework for human health behavior research through its capacity to orient questions, inform design options, and refine analytic directions. We conclude that using SI as a lens can serve as a translation mechanism in our quest to interpret the subjective world underlying patients' health and illness behavior. PMID:25316693

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

    PubMed Central

    2015-01-01

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

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

    PubMed

    Waterfield, Jon

    2015-12-25

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

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

    NASA Astrophysics Data System (ADS)

    Gade, Sharada

    2015-09-01

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

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

    NASA Astrophysics Data System (ADS)

    Houlton, H.; Keane, C.

    2012-04-01

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

  8. Biological stoichiometry: a theoretical framework connecting ecosystem ecology, evolution, and biochemistry for application in astrobiology

    NASA Astrophysics Data System (ADS)

    Elser, James J.

    2003-07-01

    Astrobiology is an extremely wide-ranging field and thus is in special need of conceptual and theoretical frameworks that can integrate its various arenas of study. In this paper I review recent work associated with a conceptual framework known as "ecological stoichiometry" and even more recent extensions in the development of "biological stoichiometry". Ecological stoichiometry is the study of the balance of energy and multiple chemical elements in ecological interactions and has developed rapidly in the study of nutrient cycling and energy flow in aquatic food webs. It identifies the elemental composition of interacting biota as central in understanding the nature of their interactions and dynamics, including key feedbacks via nutrient recycling. Biological stoichiometry extends this mode of thinking to all types of biological systems. It especially seeks to better understand, at the biochemical and genetic levels, the factors influencing the elemental composition of living things and the evolutionary forces that drive and constrain that elemental composition. By connecting key concepts of ecosystem ecology, evolutionary biology and biochemistry, stoichiometric theory integrates biological information into a more coherent whole that holds considerable promise for application in astrobiology. Several examples of potential astrobiological applications of stoichiometric analysis are offered, including ones related to pre-biotic evolution, the Cambrian explosion, biosignatures and biological feedbacks on planetary carbon cycling.

  9. Fundamental theoretical bias in gravitational wave astrophysics and the parametrized post-Einsteinian framework

    SciTech Connect

    Yunes, Nicolas; Pretorius, Frans

    2009-12-15

    We consider the concept of fundamental bias in gravitational wave astrophysics as the assumption that general relativity is the correct theory of gravity during the entire wave-generation and propagation regime. Such an assumption is valid in the weak field, as verified by precision experiments and observations, but it need not hold in the dynamical strong-field regime where tests are lacking. Fundamental bias can cause systematic errors in the detection and parameter estimation of signals, which can lead to a mischaracterization of the Universe through incorrect inferences about source event rates and populations. We propose a remedy through the introduction of the parametrized post-Einsteinian framework, which consists of the enhancement of waveform templates via the inclusion of post-Einsteinian parameters. These parameters would ostensibly be designed to interpolate between templates constructed in general relativity and well-motivated alternative theories of gravity, and also include extrapolations that follow sound theoretical principles, such as consistency with conservation laws and symmetries. As an example, we construct parametrized post-Einsteinian templates for the binary coalescence of equal-mass, nonspinning compact objects in a quasicircular inspiral. The parametrized post-Einsteinian framework should allow matched filtered data to select a specific set of post-Einsteinian parameters without a priori assuming the validity of the former, thus either verifying general relativity or pointing to possible dynamical strong-field deviations.

  10. An Information-Theoretic Framework for Improving Imperfect Dynamical Predictions Via Multi-Model Ensemble Forecasts

    NASA Astrophysics Data System (ADS)

    Branicki, Michal; Majda, Andrew J.

    2015-06-01

    This work focuses on elucidating issues related to an increasingly common technique of multi-model ensemble (MME) forecasting. The MME approach is aimed at improving the statistical accuracy of imperfect time-dependent predictions by combining information from a collection of reduced-order dynamical models. Despite some operational evidence in support of the MME strategy for mitigating the prediction error, the mathematical framework justifying this approach has been lacking. Here, this problem is considered within a probabilistic/stochastic framework which exploits tools from information theory to derive a set of criteria for improving probabilistic MME predictions relative to single-model predictions. The emphasis is on a systematic understanding of the benefits and limitations associated with the MME approach, on uncertainty quantification, and on the development of practical design principles for constructing an MME with improved predictive performance. The conditions for prediction improvement via the MME approach stem from the convexity of the relative entropy which is used here as a measure of the lack of information in the imperfect models relative to the resolved characteristics of the truth dynamics. It is also shown how practical guidelines for MME prediction improvement can be implemented in the context of forced response predictions from equilibrium with the help of the linear response theory utilizing the fluctuation-dissipation formulas at the unperturbed equilibrium. The general theoretical results are illustrated using exactly solvable stochastic non-Gaussian test models.

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

    PubMed

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

    2015-01-01

    This paper provides an overview of the construction of a conceptual framework regarding ICT-Assistive Technology (ICT-AT) competence development, designed to gain awareness of the elements involved and to facilitate the understanding and exchange among stakeholders of the ENTELIS (European Network for Technology Enhanced Learning in an Inclusive Society) project. The framework was designed based on the basic principles of Activity Theory, which however have been adapted and adjusted to the project's objectives. Hence, it includes a map of actors and other parameters functioning in a person surrounding "ecosystem", and it allows us to understand and map roles, expectations, barriers, as well as to devise solutions to tackle digital divide. Taking as a starting and central point the person and his/her wish to self-determination and fulfilment (quality of life) and the related needs, it provides a map of how the various concepts and variables interact within the theoretical and methodological perspective of the collection, description and assessment of experiences in ICT-AT education and competences development of persons with disabilities (PwD) of all ages. The conceptual framework represents two interacting learning activity systems: (a) the internal system of the end-user, which includes the end-user and his/her needs, the setting where learning takes place and the other actors involved, and (b) the external system, which embraces the internal system but also wider issues of policy and practice and experiences and 'actors' that contribute to the development and use of ICT and ICT-AT skills in all areas of life. The elements of these systems and their interaction provide the basis for analysing experiences and advancing knowledge relevant for bridging the digital divide. PMID:26294545

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

    PubMed Central

    Lüdecke, Daniel

    2014-01-01

    Introduction Health care providers seek to improve patient-centred care. Due to fragmentation of services, this can only be achieved by establishing integrated care partnerships. The challenge is both to control costs while enhancing the quality of care and to coordinate this process in a setting with many organisations involved. The problem is to establish control mechanisms, which ensure sufficiently consideration of patient centredness. Theory and methods Seventeen qualitative interviews have been conducted in hospitals of metropolitan areas in northern Germany. The documentary method, embedded into a systems theoretical framework, was used to describe and analyse the data and to provide an insight into the specific perception of organisational behaviour in integrated care. Results The findings suggest that integrated care partnerships rely on networks based on professional autonomy in the context of reliability. The relationships of network partners are heavily based on informality. This correlates with a systems theoretical conception of organisations, which are assumed autonomous in their decision-making. Conclusion and discussion Networks based on formal contracts may restrict professional autonomy and competition. Contractual bindings that suppress the competitive environment have negative consequences for patient-centred care. Drawbacks remain due to missing self-regulation of the network. To conclude, less regimentation of integrated care partnerships is recommended. PMID:25411573

  13. Theoretical framework for nanoparticle reactivity as a function of aggregation state.

    PubMed

    Hotze, Ernest M; Bottero, Jean-Yves; Wiesner, Mark R

    2010-07-01

    Theory is developed that relates the reactivity of nanoparticles to the structure of aggregates they may form in suspensions. This theory is applied to consider the case of reactive oxygen species (ROS) generation by photosensitization of C(60) fullerenes. Variations in aggregate structure and size appear to account for an apparent paradox in ROS generation as calculated using values for the photochemical kinetics of fullerene (C(60)) and its hydroxylated derivative, fullerol (C(60)(OH)(22-24)) and assuming that structure varies between compact and fractal objects. A region of aggregation-suppressed ROS production is identified where interactions between the particles in compact aggregates dominate the singlet oxygen production. Intrinsic kinetic properties dominate when aggregates are small and/or are characterized by low fractal dimensions. Pseudoglobal sensitivity analysis of model input variables verifies that fractal dimension, and by extension aggregation state, is the most sensitive model parameter when kinetics are well-known. This theoretical framework qualitatively predicts ROS production by fullerol suspensions 2 orders of magnitude higher compared with aggregates of largely undifferentiated C(60) despite nearly an order of magnitude higher quantum yield for the undifferentiated C(60) based on measurements for single molecules. Similar to C(60), other primary nanoparticles will exist as aggregates in many environmental and laboratory suspensions. This work provides a theoretical basis for understanding how the structure of nanoparticle aggregates may affect their reactivity. PMID:20527955

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

    NASA Astrophysics Data System (ADS)

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

    2013-12-01

    The most densely populated areas of the world are usually located in coastal areas near estuaries. As a result, estuaries are often subject to intense human interventions, such as dredging for navigation, dam construction and fresh water withdrawal etc., which in some areas has led to serious deterioration of invaluable ecosystems. Hence it is important to understand the influence of such interventions on tidal dynamics in these areas. In this study, we present one consistent theoretical framework for tidal hydrodynamics, which can be used as a rapid assessment technique that assist policy maker and managers to make considered decisions for the protection and management of estuarine environment when assessing the effect of human interventions in estuaries. Analytical solutions to the one-dimensional St. Venant equations for the tidal hydrodynamics in convergent unbounded estuaries with negligible river discharge can be cast in the form of a set of four implicit dimensionless equations for phase lag, velocity amplitude, damping, and wave celerity, as a function of two localized parameters describing friction and convergence. This method allows for the comparison of the different analytical approaches by rewriting the different solutions in the same format. In this study, classical and more recent formulations are compared, showing the differences and similarities associated to their specific simplifications. The envelope method, which is based on the consideration of the dynamics at high water and low water, can be used to derive damping equations that use different friction approximations. This results in as many analytical solutions, and thereby allows one to build a consistent theoretical framework. Analysis of the asymptotic behaviour of the equations shows that an equilibrium tidal amplitude exits reflecting the balance between friction and channel convergence. The framework is subsequently extended to take into account the effect of river discharge. Hence, the analytical solutions are applicable even in the upstream part of an estuary, where the influence of river discharge is remarkable. The proposed analytical solutions are transparent and practical, allowing a quantitative and qualitative assessment of human interventions (e.g., dredging, flow reduction) on tidal dynamics. Moreover, they are rapid assessment techniques that enable the users to set up a simple model and to understand the functioning of the system with a minimum of information required. The analytical model is illustrated in three large-scale estuaries with significant influence by human activities, i.e., the Scheldt estuary in the Netherlands, the Modaomen and the Yangtze estuaries in China. In these estuaries, the correspondence with observations is good, which suggests that the proposed model is a useful, yet realistic and reliable instrument for quick detection of the effect of human interventions on tidal dynamics and subsequent environmental issues, such as salt intrusion.

  15. A theoretical study of acoustic glitches in low-mass main-sequence stars

    SciTech Connect

    Verma, Kuldeep; Antia, H. M.; Basu, Sarbani; Mazumdar, Anwesh E-mail: antia@tifr.res.in E-mail: anwesh@tifr.res.in

    2014-10-20

    There are regions in stars, such as ionization zones and the interface between radiative and convective regions, that cause a localized sharp variation in the sound speed. These are known as 'acoustic glitches'. Acoustic glitches leave their signatures on the oscillation frequencies of stars, and hence these signatures can be used as diagnostics of these regions. In particular, the signatures of these glitches can be used as diagnostics for the position of the second helium ionization zone and that of the base of the envelope convection zone. With the help of stellar models, we study the properties of these acoustic glitches in main-sequence stars. We find that the acoustic glitch due to the helium ionization zone does not correspond to the dip in the adiabatic index Γ{sub 1} caused by the ionization of He II, but to the peak in Γ{sub 1} between the He I and He II ionization zones. We find that it is easiest to study the acoustic glitch that is due to the helium ionization zone in stars with masses in the range 0.9-1.2 M {sub ☉}.

  16. A Theoretical Framework for Understanding the Effects of Saharan Mineral Dust Aerosols on African Easterly Waves

    NASA Astrophysics Data System (ADS)

    Nathan, T. R.; Grogan, D.; Chen, S.

    2013-12-01

    Studies have shown that a large fraction of the intense hurricanes observed over the Atlantic Ocean originate as African easterly waves (AEWs). Of the many processes that affect the propagation, growth and structure of AEWs, the effects of Saharan mineral dust aerosols on AEWs remains an outstanding scientific problem. With this in mind, a new theoretical framework is presented that illuminates causal relationships between Saharan dust and the linear dynamics of AEWs. The framework is built on a quasi-geostrophic system governed by coupled equations for potential vorticity, temperature, and dust continuity. The radiative-dust heating rate accounts for both shortwave and longwave radiative transfer. The source of dust is due to surface emission, which depends on surface wind; the sinks of dust are due to sedimentation and dry deposition. A perturbation analysis yields analytical expressions for the propagation and growth characteristics of the model's AEWs. These expressions are functions of vertically and meridionally averaged wave activity, which depends on wave spatial structure, dust-radiative heating, and the background distributions of wind, temperature, and dust mixing ratio. More specifically, the propagation and growth of the AEWs depend on the amount of dust lofted from the surface by the wind, and the meridional and vertical gradients of the basic state dust distribution, which are modulated by the Doppler-shifted frequency. Idealized cases are presented that show the effects of Saharan dust on the propagation, group velocity, growth, structure, and wave fluxes of AEWs. The clarity of the expressions connecting dust aerosols to the linear properties of AEWs provides an important interpretive tool for analyzing results obtained from comprehensive model simulations of AEWs, such as those produced by the Weather Research and Forecasting (WRF) model.

  17. Measuring determinants of implementation behavior: psychometric properties of a questionnaire based on the theoretical domains framework

    PubMed Central

    2014-01-01

    Background To be able to design effective strategies to improve healthcare professionals’ implementation behaviors, a valid and reliable questionnaire is needed to assess potential implementation determinants. The present study describes the development of the Determinants of Implementation Behavior Questionnaire (DIBQ) and investigates the reliability and validity of this Theoretical Domains Framework (TDF)-based questionnaire. Methods The DIBQ was developed to measure the potential behavioral determinants of the 12-domain version of the TDF (Michie et al., 2005). We identified existing questionnaires including items assessing constructs within TDF domains and developed new items where needed. Confirmatory factor analysis was used to examine whether the predefined structure of the TDF-based questionnaire was supported by the data. Cronbach’s alpha was calculated to assess internal consistency reliability of the questionnaire, and domains’ discriminant validity was investigated. Results We developed an initial questionnaire containing 100 items assessing 12 domains. Results obtained from confirmatory factor analysis and Cronbach’s alpha resulted in the final questionnaire consisting of 93 items assessing 18 domains, explaining 63.3% of the variance, and internal consistency reliability values ranging from .68 to .93. Domains demonstrated good discriminant validity, although the domains ‘Knowledge’ and ‘Skills’ and the domains ‘Skills’ and ‘Social/professional role and identity’ were highly correlated. Conclusions We have developed a valid and reliable questionnaire that can be used to assess potential determinants of healthcare professional implementation behavior following the theoretical domains of the TDF. The DIBQ can be used by researchers and practitioners who are interested in identifying determinants of implementation behaviors in order to be able to develop effective strategies to improve healthcare professionals’ implementation behaviors. Furthermore, the findings provide a novel validation of the TDF and indicate that the domain ‘Environmental context and resources’ might be divided into several environment-related domains. PMID:24641907

  18. A Theoretical Framework for Combining Techniques that Probe the Link Between Galaxies and Dark Matter

    NASA Astrophysics Data System (ADS)

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

    2011-09-01

    We develop a theoretical framework that combines measurements of galaxy-galaxy lensing, galaxy clustering, and the galaxy stellar mass function in a self-consistent manner. While considerable effort has been invested in exploring each of these probes individually, attempts to combine them are still in their infancy. These combinations have the potential to elucidate the galaxy-dark matter connection and the galaxy formation physics responsible for it, as well as to constrain cosmological parameters and to test the nature of gravity. In this paper, we focus on a theoretical model that describes the galaxy-dark matter connection based on standard halo occupation distribution techniques. Several key modifications enable us to extract additional parameters that determine the stellar-to-halo mass relation and to simultaneously fit data from multiple probes while allowing for independent binning schemes for each probe. We construct mock catalogs from numerical simulations to investigate the effects of sample variance and covariance for each probe. Finally, we analyze how trends in each of the three observables impact the derived parameters of the model. In particular, we investigate various features of the observed galaxy stellar mass function (low-mass slope, "plateau," knee, and high-mass cutoff) and show how each feature is related to the underlying relationship between stellar and halo mass. We demonstrate that the observed "plateau" feature in the stellar mass function at M * ~ 2 × 1010 M sun is due to the transition that occurs in the stellar-to-halo mass relation at Mh ~ 1012 M sun from a low-mass power-law regime to a sub-exponential function at higher stellar mass.

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

    SciTech Connect

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

    2011-09-01

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

  20. A theoretical framework for the incorporation of history in science education

    NASA Astrophysics Data System (ADS)

    Klassen, James Stephen

    This thesis formulates a theoretical framework for the incorporation of history of science in science teaching, which, it is argued, is essential to laying a stable foundation for instructional design and future empirical studies. It is assumed that the historical approach to teaching science no longer needs defending and that contextual methods are a pedagogically sound approach to learning. Various cognitive and learning theories suggest that there are five distinct contexts that are important in engaging learners: the theoretical, practical, social, historical, and affective. On the basis of these five contexts, a model for teaching and learning is constructed, in which the story assumes a major role in engaging the learner affectively. This model is named the Story-Driven Contextual Approach (SDCA). The SDCA is introduced to students by means of a narrative, encouraging students to become actively engaged with the five contexts. In the SDCA, students are seen as novice researchers and the teacher as a research director. The place and nature of the historical science story in science education is a relatively undeveloped area in the literature. This thesis argues that the development of the events in a story proceed in the same fashion as the steps in learning a concept. A structural model of a story consisting of a three-stage temporal sequence, which includes a causative element, is presented and developed. It is argued that the conceptual change process, from a temporal perspective, can also be viewed as a three-stage sequence similar to the story. The story can, in this light, be thought of as the re-enactment of a particular type of learning process. This knowledge about the nature of stories can serve as a guiding principle in the designing and writing of effective stories based on the history of science, which are to be incorporated with the SDCA. The SDCA was tested in a university physics class using a constructed story which portrays the heroic personal and scientific efforts of the nineteenth century physicist Lord Kelvin in laying the first successful trans-Atlantic cable. Students designed and undertook various practical and theoretical exercises in the SDCA and observations on its implementation are reported.

  1. The growth threshold conjecture: a theoretical framework for understanding T-cell tolerance.

    PubMed

    Arias, Clemente F; Herrero, Miguel A; Cuesta, José A; Acosta, Francisco J; Fernández-Arias, Cristina

    2015-07-01

    Adaptive immune responses depend on the capacity of T cells to target specific antigens. As similar antigens can be expressed by pathogens and host cells, the question naturally arises of how can T cells discriminate friends from foes. In this work, we suggest that T cells tolerate cells whose proliferation rates remain below a permitted threshold. Our proposal relies on well-established facts about T-cell dynamics during acute infections: T-cell populations are elastic (they expand and contract) and they display inertia (contraction is delayed relative to antigen removal). By modelling inertia and elasticity, we show that tolerance to slow-growing populations can emerge as a population-scale feature of T cells. This result suggests a theoretical framework to understand immune tolerance that goes beyond the self versus non-self dichotomy. It also accounts for currently unexplained observations, such as the paradoxical tolerance to slow-growing pathogens or the presence of self-reactive T cells in the organism. PMID:26587263

  2. An inverse finite element method for beam shape sensing: theoretical framework and experimental validation

    NASA Astrophysics Data System (ADS)

    Gherlone, Marco; Cerracchio, Priscilla; Mattone, Massimiliano; Di Sciuva, Marco; Tessler, Alexander

    2014-04-01

    Shape sensing, i.e., reconstruction of the displacement field of a structure from surface-measured strains, has relevant implications for the monitoring, control and actuation of smart structures. The inverse finite element method (iFEM) is a shape-sensing methodology shown to be fast, accurate and robust. This paper aims to demonstrate that the recently presented iFEM for beam and frame structures is reliable when experimentally measured strains are used as input data. The theoretical framework of the methodology is first reviewed. Timoshenko beam theory is adopted, including stretching, bending, transverse shear and torsion deformation modes. The variational statement and its discretization with C0-continuous inverse elements are briefly recalled. The three-dimensional displacement field of the beam structure is reconstructed under the condition that least-squares compatibility is guaranteed between the measured strains and those interpolated within the inverse elements. The experimental setup is then described. A thin-walled cantilevered beam is subjected to different static and dynamic loads. Measured surface strains are used as input data for shape sensing at first with a single inverse element. For the same test cases, convergence is also investigated using an increasing number of inverse elements. The iFEM-recovered deflections and twist rotations are then compared with those measured experimentally. The accuracy, convergence and robustness of the iFEM with respect to unavoidable measurement errors, due to strain sensor locations, measurement systems and geometry imperfections, are demonstrated for both static and dynamic loadings.

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

    PubMed

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

    2014-01-01

    Stigma is a barrier to HIV health seeking, but little is known about institutional and structural expressions of stigma in HIV testing. This study examines evidence of institutional and structural stigma in the HIV testing process. A qualitative, grounded theory study was conducted using secondary data from a 2011 HIV test site evaluation data in a Midwestern, moderate HIV incidence state. Expressions of structural and institutional stigma were found with over half of the testing sites and at three stages of the HIV testing visit. Examples of structural stigma included social geography, organization, and staff behavior at first encounter and reception, and staff behavior when experiencing the actual HIV test. Institutional stigma was socially expressed through staff behavior at entry/reception and when experiencing the HIV test. The emerging elements demonstrate the potential compounding of stigma experiences with deleterious effect. Study findings may inform future development of a theoretical framework. In practice, findings can guide organizations seeking to reduce HIV testing barriers, as they provide a window into how test seekers experience HIV test sites at first encounter, entry/reception, and at testing stages; and can identify how stigma might be intensified by structural and institutional expressions. PMID:24313812

  4. Molecular recognition of adeninium cations on anionic metal-oxalato frameworks: an experimental and theoretical analysis.

    PubMed

    García-Teran, Juan P; Castillo, Oscar; Luque, Antonio; García-Couceiro, Urko; Beobide, Garikoitz; Roman, Pascual

    2007-04-30

    Reactions of adenine with water-soluble oxalato complexes at acidic pH give the compounds (1H,9H-ade)2[Cu(ox)2(H2O)] (1) [H2ade=adeninium cation (1+), ox=oxalato ligand (2-)] and (3H,7H-ade)2[M(ox)2(H2O)2].2H2O [M(II)=Co (2), Zn (3)]. The X-ray single crystal analyses show that the supramolecular architecture of all compounds is built up of anionic sheets of metal-oxalato-water complexes and ribbons of cationic nucleobases among them to afford lamellar inorganic-organic hybrid materials. The molecular recognition process between the organic and the inorganic frameworks determines the isolated tautomeric form of the adeninium cation found in the crystal structures: the canonical 1H,9H for compound 1, and the first solid-state characterized 3H,7H-adeninium tautomer for compounds 2 and 3. Density functional theory calculations have been performed to study the stability of the protonated nucleobase forms and their hydrogen-bonded associations by comparing experimental and theoretical results. PMID:17375914

  5. Assessment of Environmental Enteropathy in the MAL-ED Cohort Study: Theoretical and Analytic Framework

    PubMed Central

    Kosek, Margaret; Guerrant, Richard L.; Kang, Gagandeep; Bhutta, Zulfiqar; Yori, Pablo Peñataro; Gratz, Jean; Gottlieb, Michael; Lang, Dennis; Lee, Gwenyth; Haque, Rashidul; Mason, Carl J.; Ahmed, Tahmeed; Lima, Aldo; Petri, William A.; Houpt, Eric; Olortegui, Maribel Paredes; Seidman, Jessica C.; Mduma, Estomih; Samie, Amidou; Babji, Sudhir

    2014-01-01

    Individuals in the developing world live in conditions of intense exposure to enteric pathogens due to suboptimal water and sanitation. These environmental conditions lead to alterations in intestinal structure, function, and local and systemic immune activation that are collectively referred to as environmental enteropathy (EE). This condition, although poorly defined, is likely to be exacerbated by undernutrition as well as being responsible for permanent growth deficits acquired in early childhood, vaccine failure, and loss of human potential. This article addresses the underlying theoretical and analytical frameworks informing the methodology proposed by the Etiology, Risk Factors and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) cohort study to define and quantify the burden of disease caused by EE within a multisite cohort. Additionally, we will discuss efforts to improve, standardize, and harmonize laboratory practices within the MAL-ED Network. These efforts will address current limitations in the understanding of EE and its burden on children in the developing world. PMID:25305293

  6. Development, theoretical framework, and evaluation of a parent and teacher-delivered intervention on adolescent vaccination.

    PubMed

    Gargano, Lisa M; Herbert, Natasha L; Painter, Julia E; Sales, Jessica M; Vogt, Tara M; Morfaw, Christopher; Jones, LaDawna M; Murray, Dennis; DiClemente, Ralph J; Hughes, James M

    2014-07-01

    The Advisory Committee on Immunization Practices recommended immunization schedule for adolescents includes three vaccines (tetanus, diphtheria, and acellular pertussis [Tdap]; human papillomavirus [HPV] vaccine; and meningococcal conjugate vaccine [MCV4]) and an annual influenza vaccination. Given the increasing number of recommended vaccines for adolescents and health and economic costs associated with nonvaccination, it is imperative that effective strategies for increasing vaccination rates among adolescents are developed. This article describes the development, theoretical framework, and initial first-year evaluation of an intervention designed to promote vaccine acceptance among a middle and high school-based sample of adolescents and their parents in eastern Georgia. Adolescents, parents, and teachers were active participants in the development of the intervention. The intervention, which consisted of a brochure for parents and a teacher-delivered curriculum for adolescents, was guided by constructs from the health belief model and theory of reasoned action. Evaluation results indicated that our intervention development methods were successful in creating a brochure that met cultural relevance and the literacy needs of parents. We also demonstrated an increase in student knowledge of and positive attitudes toward vaccines. To our knowledge, this study is the first to extensively engage middle and high school students, parents, and teachers in the design and implementation of key theory-based educational components of a school-based, teacher-delivered adolescent vaccination intervention. PMID:24440920

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

    PubMed Central

    Merrick, Kathryn E.; Shafi, Kamran

    2013-01-01

    An emerging body of research is focusing on understanding and building artificial systems that can achieve open-ended development influenced by intrinsic motivations. In particular, research in robotics and machine learning is yielding systems and algorithms with increasing capacity for self-directed learning and autonomy. Traditional software architectures and algorithms are being augmented with intrinsic motivations to drive cumulative acquisition of knowledge and skills. Intrinsic motivations have recently been considered in reinforcement learning, active learning and supervised learning settings among others. This paper considers game theory as a novel setting for intrinsic motivation. A game theoretic framework for intrinsic motivation is formulated by introducing the concept of optimally motivating incentive as a lens through which players perceive a game. Transformations of four well-known mixed-motive games are presented to demonstrate the perceived games when players' optimally motivating incentive falls in three cases corresponding to strong power, affiliation and achievement motivation. We use agent-based simulations to demonstrate that players with different optimally motivating incentive act differently as a result of their altered perception of the game. We discuss the implications of these results both for modeling human behavior and for designing artificial agents or robots. PMID:24198797

  8. The growth threshold conjecture: a theoretical framework for understanding T-cell tolerance

    PubMed Central

    Arias, Clemente F.; Herrero, Miguel A.; Cuesta, José A.; Acosta, Francisco J.; Fernández-Arias, Cristina

    2015-01-01

    Adaptive immune responses depend on the capacity of T cells to target specific antigens. As similar antigens can be expressed by pathogens and host cells, the question naturally arises of how can T cells discriminate friends from foes. In this work, we suggest that T cells tolerate cells whose proliferation rates remain below a permitted threshold. Our proposal relies on well-established facts about T-cell dynamics during acute infections: T-cell populations are elastic (they expand and contract) and they display inertia (contraction is delayed relative to antigen removal). By modelling inertia and elasticity, we show that tolerance to slow-growing populations can emerge as a population-scale feature of T cells. This result suggests a theoretical framework to understand immune tolerance that goes beyond the self versus non-self dichotomy. It also accounts for currently unexplained observations, such as the paradoxical tolerance to slow-growing pathogens or the presence of self-reactive T cells in the organism. PMID:26587263

  9. Linking predator risk and uncertainty to adaptive forgetting: a theoretical framework and empirical test using tadpoles

    PubMed Central

    Ferrari, Maud C. O.; Brown, Grant E.; Bortolotti, Gary R.; Chivers, Douglas P.

    2010-01-01

    Hundreds of studies have examined how prey animals assess their risk of predation. These studies work from the basic tennet that prey need to continually balance the conflicting demands of predator avoidance with activities such as foraging and reproduction. The information that animals gain regarding local predation risk is most often learned. Yet, the concept of ‘memory’ in the context of predation remains virtually unexplored. Here, our goal was (i) to determine if the memory window associated with predator recognition is fixed or flexible and, if it is flexible, (ii) to identify which factors affect the length of this window and in which ways. We performed an experiment on larval wood frogs, Rana sylvatica, to test whether the risk posed by, and the uncertainty associated with, the predator would affect the length of the tadpoles' memory window. We found that as the risk associated with the predator increases, tadpoles retained predator-related information for longer. Moreover, if the uncertainty about predator-related information increases, then prey use this information for a shorter period. We also present a theoretical framework aiming at highlighting both intrinsic and extrinsic factors that could affect the memory window of information use by prey individuals. PMID:20236976

  10. Assessment of environmental enteropathy in the MAL-ED cohort study: theoretical and analytic framework.

    PubMed

    Kosek, Margaret; Guerrant, Richard L; Kang, Gagandeep; Bhutta, Zulfiqar; Yori, Pablo Peñataro; Gratz, Jean; Gottlieb, Michael; Lang, Dennis; Lee, Gwenyth; Haque, Rashidul; Mason, Carl J; Ahmed, Tahmeed; Lima, Aldo; Petri, William A; Houpt, Eric; Olortegui, Maribel Paredes; Seidman, Jessica C; Mduma, Estomih; Samie, Amidou; Babji, Sudhir

    2014-11-01

    Individuals in the developing world live in conditions of intense exposure to enteric pathogens due to suboptimal water and sanitation. These environmental conditions lead to alterations in intestinal structure, function, and local and systemic immune activation that are collectively referred to as environmental enteropathy (EE). This condition, although poorly defined, is likely to be exacerbated by undernutrition as well as being responsible for permanent growth deficits acquired in early childhood, vaccine failure, and loss of human potential. This article addresses the underlying theoretical and analytical frameworks informing the methodology proposed by the Etiology, Risk Factors and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) cohort study to define and quantify the burden of disease caused by EE within a multisite cohort. Additionally, we will discuss efforts to improve, standardize, and harmonize laboratory practices within the MAL-ED Network. These efforts will address current limitations in the understanding of EE and its burden on children in the developing world. PMID:25305293

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

    PubMed

    Merrick, Kathryn E; Shafi, Kamran

    2013-01-01

    An emerging body of research is focusing on understanding and building artificial systems that can achieve open-ended development influenced by intrinsic motivations. In particular, research in robotics and machine learning is yielding systems and algorithms with increasing capacity for self-directed learning and autonomy. Traditional software architectures and algorithms are being augmented with intrinsic motivations to drive cumulative acquisition of knowledge and skills. Intrinsic motivations have recently been considered in reinforcement learning, active learning and supervised learning settings among others. This paper considers game theory as a novel setting for intrinsic motivation. A game theoretic framework for intrinsic motivation is formulated by introducing the concept of optimally motivating incentive as a lens through which players perceive a game. Transformations of four well-known mixed-motive games are presented to demonstrate the perceived games when players' optimally motivating incentive falls in three cases corresponding to strong power, affiliation and achievement motivation. We use agent-based simulations to demonstrate that players with different optimally motivating incentive act differently as a result of their altered perception of the game. We discuss the implications of these results both for modeling human behavior and for designing artificial agents or robots. PMID:24198797

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

    ERIC Educational Resources Information Center

    Niemi, Hannele

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

  13. Contextualized analysis of a needs assessment using the Theoretical Domains Framework: a case example in endocrinology

    PubMed Central

    2014-01-01

    Background The Theoretical Domains Framework (TDF) is a set of 14 domains of behavior change that provide a framework for the critical issues and factors influencing optimal knowledge translation. Considering that a previous study has identified optimal knowledge translation techniques for each TDF domain, it was hypothesized that the TDF could be used to contextualize and interpret findings from a behavioral and educational needs assessment. To illustrate this hypothesis, findings and recommendations drawn from a 2012 national behavioral and educational needs assessment conducted with healthcare providers who treat and manage Growth and Growth Hormone Disorders, will be discussed using the TDF. Methods This needs assessment utilized a mixed-methods research approach that included a combination of: [a] data sources (Endocrinologists (n:120), Pediatric Endocrinologists (n:53), Pediatricians (n:52)), [b] data collection methods (focus groups, interviews, online survey), [c] analysis methodologies (qualitative - analyzed through thematic analysis, quantitative - analyzed using frequencies, cross-tabulations, and gap analysis). Triangulation was used to generate trustworthy findings on the clinical practice gaps of endocrinologists, pediatric endocrinologists, and general pediatricians in their provision of care to adult patients with adult growth hormone deficiency or acromegaly, or children/teenagers with pediatric growth disorders. The identified gaps were then broken into key underlying determinants, categorized according to the TDF domains, and linked to optimal behavioral change techniques. Results The needs assessment identified 13 gaps, each with one or more underlying determinant(s). Overall, these determinants were mapped to 9 of the 14 TDF domains. The Beliefs about Consequences domain was identified as a contributing determinant to 7 of the 13 challenges. Five of the gaps could be related to the Skills domain, while three were linked to the Knowledge domain. Conclusions The TDF categorization of the needs assessment findings allowed recommendation of appropriate behavior change techniques for each underlying determinant, and facilitated communication and understanding of the identified issues to a broader audience. This approach provides a means for health education researchers to categorize gaps and challenges identified through educational needs assessments, and facilitates the application of these findings by educators and knowledge translators, by linking the gaps to recommended behavioral change techniques. PMID:25060235

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

    PubMed Central

    2013-01-01

    Background The health care quality improvement movement is a complex enterprise. Implementing clinical quality initiatives requires attitude and behaviour change on the part of clinicians, but this has proven to be difficult. In an attempt to solve this kind of behavioural challenge, the theoretical domains framework (TDF) has been developed. The TDF consists of 14 domains from psychological and organisational theory said to influence behaviour change. No systematic research has been conducted into the ways in which clinical quality initiatives map on to the domains of the framework. We therefore conducted a qualitative mapping experiment to determine to what extent, and in what ways, the TDF is relevant to the implementation of clinical quality interventions. Methods We conducted a thematic synthesis of the qualitative literature exploring clinicians’ perceptions of various clinical quality interventions. We analysed and synthesised 50 studies in total, in five domains of clinical quality interventions: clinical quality interventions in general, structural interventions, audit-type interventions, interventions aimed at making practice more evidence-based, and risk management interventions. Data were analysed thematically, followed by synthesis of these themes into categories and concepts, which were then mapped to the domains of the TDF. Results Our results suggest that the TDF is highly relevant to the implementation of clinical quality interventions. It can be used to map most, if not all, of the attitudinal and behavioural barriers and facilitators of uptake of clinical quality interventions. Each of these 14 domains appeared to be relevant to many different types of clinical quality interventions. One possible additional domain might relate to perceived trustworthiness of those instituting clinical quality interventions. Conclusions The TDF can be usefully applied to a wide range of clinical quality interventions. Because all 14 of the domains emerged as relevant, and we did not identify any obvious differences between different kinds of clinical quality interventions, our findings support an initially broad approach to identifying barriers and facilitators, followed by a “drilling down” to what is most contextually salient. In future, it may be possible to establish a model of clinical quality policy implementation using the TDF. PMID:24359085

  15. The tectono-stratigraphic framework and evolution of southwestern Maine and southeastern New Hampshire

    USGS Publications Warehouse

    Hussey, Arthur M., II.; Bothner, Wallace A.; Alienikoff, John N.

    2010-01-01

    Five belts of metamorphosed sedimentary and volcanic rocks underlie southwestern Maine and southeastern New Hampshire: Middle Ordovician Falmouth-Brunswick sequence; Middle and Late Ordovician Casco Bay Group, and Late Ordovician to Early Silurian rocks of the Merribuckfred Basin; Late Ordovician to Early Silurian rocks of the East Harpswell Group; Silurian to Early Devonian rocks of the Central Maine Basin; and highly tectonized enigmatic rocks of the Rye complex of uncertain age. Stratigraphic reassessment and new U/Pb zircon ages support a model of east-directed Middle Ordovician subduction beneath Miramichi, a peri-Gondwanan block, and formation of the Falmouth-Brunswick–Casco Bay volcanic arc complex that is roughly correlative with arc activity on strike in New Brunswick. Passive Late Ordovician sedimentation in a reducing restricted backarc basin followed. Late Ordovician to Early Silurian volcanic rocks and volcanogenic sediments (East Harpswell Group) support west-directed subduction under the Miramichi block. Late Ordovician to Early Silurian turbidites accumulated in the Merribuckfred Basin between the Falmouth-Brunswick–Casco Bay arc and Ganderia to the east. The collision of Ganderia with the Falmouth Brunswick arc in Late Silurian time represents an early phase of the Acadian orogeny, during which the Merribuckfred rocks were deformed, metamorphosed, intruded, and uplifted. Simultaneously and inboard, the Central Maine Basin received sediment eroded mostly from Laurentia. Later, during the Late Silurian and Early Devonian, uplifted Merribuckfred basin rocks became the major source of sediments for the Central Maine Basin. A later phase of the Acadian orogeny resulted in Middle Devonian deformation, metamorphism, and intrusion of rocks of all six belts.

  16. Mathematical Evidence-theoretic Framework for Information Fusion of Disaster Scene Big Data

    NASA Astrophysics Data System (ADS)

    Chen, Z.

    2014-12-01

    The remote sensing community and geospatial industries are embracing the paradigm of 'big data'. This trend is in one hand due to the fact that heterogeneous remote sensors are producing tremendous amounts of earth observation (EO) data every day; on the other hand it is aspired by the promise that big data computing may be the fourth paradigm for scientific discovery. Many traditional techniques have been developed and will continue to be useful to deal with earth-observation big data, for examples, pansharpening, fusion of data with different electromagnetic nature (e.g. color images and SAR images), and use of multi-sensor data for improved land-cover classification. However, two limitations are recognized for these techniques, which include: (1) first, these methods are tightly dependent on a two-dimensional grid scale; and (2) second, temporal, spatial and causal relations are not intelligently treated. These limitations render them insufficient when used to attack the emerging Disaster Scene Big Data (DSBD). DSBD emerges as a geological or climatic hazard unfolds into a disaster. In the example of an earthquake, disaster data starts accruing as the ground shaking is being monitored. Along the time scale, heterogeneous multi-sensor data arise: EO data with various electromagnetic nature, oblique images, airborne/terrestrial active (Lidar) data, and the recently emerged crowdsourcing data. Neither theoretical models nor effective methods exist to date that can sufficiently fuse these data towards revealing the 'ground-truth' of the disaster effects, for example, damage to built objects. This presentation will present an augmented evidence-theoretic framework based on the classical Dempster-Shafer theory. With a focus on reasoning the ground-truth of build-object damage, causal, correlational and relational evidences will be defined considering their temporal and spatial scales. The newly developed graph-based learning approach will be explored for estimating the belief-plausibility interval of the ground-truth damage. Case-study using recent earthquake disaster data (e.g. the 2011 Christchurch Earthquake) will be discussed.

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

    PubMed Central

    2012-01-01

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

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

    PubMed

    Bowleg, Lisa

    2012-07-01

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

  19. A Critical Review of the Theoretical Frameworks and the Conceptual Factors in the Adoption of Clinical Decision Support Systems.

    PubMed

    Khong, Peck Chui Betty; Holroyd, Eleanor; Wang, Wenru

    2015-12-01

    The clinical decision support system is utilized to translate knowledge into evidence-based practice in clinical settings. Many studies have been conducted to understand users' adoption of the clinical decision support system. A critical review was conducted to understand the theoretical or conceptual frameworks used to inform the studies on the adoption of the clinical decision support system. The review identified 15 theoretical and conceptual frameworks using multiple hybrids of theories and concepts. The Technology Acceptance Model was the most frequently used baseline framework combined with frameworks such as the diffusion of innovation, social theory, longitudinal theory, and so on. The results from these articles yielded multiple concepts influencing the adoption of the clinical decision support system. These concepts can be recategorized into nine major concepts, namely, the information system, person (user or patient), social, organization, perceived benefits, emotions, trustability, relevance (fitness), and professionalism. None of the studies found all the nine concepts. That said, most of them have identified the information system, organization, and person concepts as three of its concepts affecting the use of the clinical decision support system. Within each of the concepts, its subconcepts were noted to be very varied. Yet each of these subconcepts has significantly contributed toward the different facets of the concepts. A pluralistic framework was built using the concepts and subconcepts to provide an overall framework construct for future study on the adoption of the clinical decision support system. PMID:26535769

  20. Evaluation of Capacity-Building Program of District Health Managers in India: A Contextualized Theoretical Framework

    PubMed Central

    Prashanth, N. S.; Marchal, Bruno; Kegels, Guy; Criel, Bart

    2014-01-01

    Performance of local health services managers at district level is crucial to ensure that health services are of good quality and cater to the health needs of the population in the area. In many low- and middle-income countries, health services managers are poorly equipped with public health management capacities needed for planning and managing their local health system. In the south Indian Tumkur district, a consortium of five non-governmental organizations partnered with the state government to organize a capacity-building program for health managers. The program consisted of a mix of periodic contact classes, mentoring and assignments and was spread over 30?months. In this paper, we develop a theoretical framework in the form of a refined program theory to understand how such a capacity-building program could bring about organizational change. A well-formulated program theory enables an understanding of how interventions could bring about improvements and an evaluation of the intervention. In the refined program theory of the intervention, we identified various factors at individual, institutional, and environmental levels that could interact with the hypothesized mechanisms of organizational change, such as staff’s perceived self-efficacy and commitment to their organizations. Based on this program theory, we formulated context–mechanism–outcome configurations that can be used to evaluate the intervention and, more specifically, to understand what worked, for whom and under what conditions. We discuss the application of program theory development in conducting a realist evaluation. Realist evaluation embraces principles of systems thinking by providing a method for understanding how elements of the system interact with one another in producing a given outcome. PMID:25121081

  1. A theoretical framework for the episodic-urban air quality management plan ( e-UAQMP)

    NASA Astrophysics Data System (ADS)

    Gokhale, Sharad; Khare, Mukesh

    The present research proposes the local urban air quality management plan which combines two different modelling approaches (hybrid model) and possesses an improved predictive ability including the 'probabilistic exceedances over norms' and their 'frequency of occurrences' and so termed, herein, as episodic-urban air quality management plan ( e-UAQMP). The e-UAQMP deals with the consequences of 'extreme' concentrations of pollutant, mainly occurring at urban 'hotspots' e.g. traffic junctions, intersections and signalized roadways and are also influenced by complexities of traffic generated 'wake' effects. The e-UAQMP (based on probabilistic approach), also acts as an efficient preventive measure to predict the 'probability of exceedances' so as to prepare a successful policy responses in relation to the protection of urban environment as well as disseminating information to its sensitive 'receptors'. The e-UAQMP may be tailored to the requirements of the local area for the policy implementation programmes. The importance of such policy-making framework in the context of current air pollution 'episodes' in urban environments is discussed. The hybrid model that is based on both deterministic and stochastic based approaches predicting the 'average' as well as 'extreme' concentration distribution of air pollutants together in form of probability has been used at two air quality control regions (AQCRs) in the Delhi city, India, in formulating and executing the e-UAQMP— first, the income tax office (ITO), one of the busiest signalized traffic intersection and second, the Sirifort, one of the busiest signalized roadways.

  2. Theoretical values of convective turnover times and Rossby numbers for solar-like, pre-main sequence stars

    NASA Astrophysics Data System (ADS)

    Landin, N. R.; Mendes, L. T. S.; Vaz, L. P. R.

    2010-02-01

    Context. Magnetic fields are at the heart of the observed stellar activity in late-type stars, and they are presumably generated by a dynamo mechanism at the interface layer (tachocline) between the radiative core and the base of the convective envelope. Aims: Since dynamo models are based on the interaction between differential rotation and convective motions, the introduction of rotation in the ATON 2.3 stellar evolutionary code allows for explorations regarding a physically consistent treatment of magnetic effects in stellar structure and evolution, even though there are formidable mathematical and numerical challenges involved. Methods: As examples of such explorations, we present theoretical estimates for both the local convective turnover time (?_c), and global convective times (?_g) for rotating pre-main sequence solar-type stars, based on up-to-date input physics for stellar models. Our theoretical predictions are compared with the previous ones available in the literature. In addition, we investigate the dependence of the convective turnover time on convection regimes, the presence of rotation and atmospheric treatment. Results: Those estimates, as opposed to the use of empirically derived values of ?_c for such matters, can be used to calculate the Rossby number Ro, which is related to the magnetic activity strength in dynamo theories and, at least for main-sequence stars, shows an observational correlation with stellar activity. More important, they can also contribute for testing stellar models against observations. Conclusions: Our theoretical values of ?_c, ?_g and Ro qualitatively agree with those published by Kim & Demarque (1996, ApJ, 457, 340). By increasing the convection efficiency, ?_g decreases for a given mass. FST models show still lower values. The presence of rotation shifts ?_g towards slightly higher values when compared with non-rotating models. The use of non-gray boundary conditions in the models yields values of ?_g smaller than in the gray approximation. Full Table 1 is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/510/A46

  3. Persuasive appeals in road safety communication campaigns: Theoretical frameworks and practical implications from the analysis of a decade of road safety campaign materials.

    PubMed

    Guttman, Nurit

    2015-11-01

    Communication campaigns are employed as an important tool to promote road safety practices. Researchers maintain road safety communication campaigns are more effective when their persuasive appeals, which are central to their communicative strategy, are based on explicit theoretical frameworks. This study's main objectives were to develop a detailed categorization of persuasive appeals used in road safety communication campaigns that differentiate between appeals that appear to be similar but differ conceptually, and to indicate the advantages, limitations and ethical issues associated with each type, drawing on behavior change theories. Materials from over 300 campaigns were obtained from 41 countries, mainly using road safety organizations' websites. Drawing on the literature, five types of main approaches were identified, and the analysis yielded a more detailed categorizations of appeals within these general categories. The analysis points to advantages, limitations, ethical issues and challenges in using different types of appeals. The discussion summarizes challenges in designing persuasive-appeals for road safety communication campaigns. PMID:26422583

  4. Consequences of Implementing Alternative Schools: Toward a Theoretical Framework for Investigating Problems.

    ERIC Educational Resources Information Center

    Eriksen, Aase; Messina, Judith

    This document applies an anthropological framework to the explanation of group relations in an attempt to implement a community school. In a West Philadelphia area, black community groups joined to establish an alternative school, but tensions and conflicts developed over pedagogical practices. According to the anthropological framework, decisions…

  5. A Theoretical Framework of the Relation between Socioeconomic Status and Academic Achievement of Students

    ERIC Educational Resources Information Center

    Lam, Gigi

    2014-01-01

    A socio-psychological analytical framework will be adopted to illuminate the relation between socioeconomic status and academic achievement. The framework puts the emphasis to incorporate micro familial factors into macro factor of the tracking system. Initially, children of the poor families always lack major prerequisite: diminution of cognitive…

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

    PubMed

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

    2011-07-01

    We apply Quinn and Rohrbaugh's (1983) competing values framework (CVF) as an organizing taxonomy to meta-analytically test hypotheses about the relationship between 3 culture types and 3 major indices of organizational effectiveness (employee attitudes, operational performance [i.e., innovation and product and service quality], and financial performance). The paper also tests theoretical suppositions undergirding the CVF by investigating the framework's nomological validity and proposed internal structure (i.e., interrelationships among culture types). Results based on data from 84 empirical studies with 94 independent samples indicate that clan, adhocracy, and market cultures are differentially and positively associated with the effectiveness criteria, though not always as hypothesized. The findings provide mixed support for the CVF's nomological validity and fail to support aspects of the CVF's proposed internal structure. We propose an alternative theoretical approach to the CVF and delineate directions for future research. PMID:21244127

  7. Can a theoretical framework help to embed alcohol screening and brief interventions in an endoscopy day-unit?

    PubMed Central

    O'Neill, G; Masson, S; Bewick, L; Doyle, J; McGovern, R; Stoker, E; Wright, H; Newbury-Birch, D

    2016-01-01

    Introduction and aims The National Institute for Health Care and Excellence recommend that alcohol screening and brief intervention (ASBI) should be routinely implemented in secondary care. This study used theoretical frameworks to understand how health professionals can be supported to adapt their behaviour and clinical practice. Design and methods Staff training and support was conducted using theoretical frameworks. A 12-week study, delivering ASBI was carried out as part of routine practice in an endoscopy day-unit. Anonymised patient data were collected using the Alcohol Use Disorders Identification Tool (AUDIT) and whether patients received a brief intervention. Staff completed the Shortened Alcohol and Alcohol Problems Perceptions Questionnaire at three time points and took part in a focus group both pre and post study. Results For staff, levels or role adequacy, role legitimacy, motivation to discuss alcohol, security in their role, job satisfaction and commitment to working with patients who drink increased during the time of the study. 1598 individual patients were seen in the department in the timeframe. Of these, 1180 patients were approached (74%); 18% (n=207) of patients were AUDIT positive. Discussion This study has shown that it is possible to reach a high number of patients in a busy hospital out-patient department and deliver ASBI by working with staff using theoretical frameworks for training. Embedding evidence-based public health interventions into routine clinical environments is complex. The social system in which professionals operate requires consideration alongside individual professionals’ real and perceived barriers and facilitators to change. PMID:26834957

  8. Main rotor free wake geometry effects on blade air loads and response for helicopters in steady maneuvers. Volume 1: Theoretical formulation and analysis of results

    NASA Technical Reports Server (NTRS)

    Sadler, S. G.

    1972-01-01

    A mathematical model and computer program were implemented to study the main rotor free wake geometry effects on helicopter rotor blade air loads and response in steady maneuvers. The theoretical formulation and analysis of results are presented.

  9. An analysis of the PPCF as a theoretical framework for an instrument to examine teacher priorities for selecting curriculum content.

    PubMed

    Ennis, C D; Hooper, L M

    1990-03-01

    The purpose of the research was to develop an instrument to examine physical education teachers' priorities for curricular decision-making. The purpose dimension of the Purpose Process Curriculum Framework (PPCF) was used as the theoretical structure for content decisions. Three studies are reported that investigate the reliability and validity of the proposed instrument. Items were evaluated for relevance and validity of the proposed instrument. They were evaluated for relevance and theoretical consistency by physical education teachers (Study 1) and curriculum specialists (Study 2). Acceptable items were then placed in a ranking format and field tested with physical educators in three school districts (Study 3). Results from Study 1 indicated that secondary level physical education teachers supported the relevance of items to reflect the educational setting in their classes. In Study 2, mean ratings of curriculum specialists established that 19 of the 22 categories were theoretically consistent with the PPCF. However, internal consistency coefficients (alpha) for 10 of the 22 purposes were less than .70. Follow-up field tests with physical educators in Study 3 indicated that only one category, joy of movement, had a coefficient above .70. In this research internal consistency coefficients were too low to make a claim for the reliability of the concept scales of the instrument. The multidimensionality of the purpose concepts raised questions regarding the validity of the PPCF and prohibited the use of the framework as a theoretical basis for instrument development. PMID:2091166

  10. Theoretical study of air forces on an oscillating or steady thin wing in a supersonic main stream

    NASA Technical Reports Server (NTRS)

    Garrick, I E; Rubinow, S I

    1947-01-01

    A theoretical study, based on the linearized equations of motion for small disturbance, is made of the air forces on wings of general plan forms moving forward at a constant supersonic speed. The boundary problem is set up for both the harmonically oscillating and the steady conditions. Two types of boundary conditions are distinguished, which are designated "purely supersonic" and "mixed supersonic." the method is illustrated by applications to a number of examples for both the steady and the oscillating conditions. The purely supersonic case involves independence of action of the upper and lower surfaces of the airfoil and present analysis is mainly concerned with this case. A discussion is first given of the fundamental or elementary solution corresponding to a moving source. The solutions for the velocity potential are then synthesized by means of integration of the fundamental solution for the moving source. The method is illustrated by applications to a number of examples for both the steady and the oscillating cases and for various plan forms, including swept wings and rectangular and triangular plan forms. The special results of a number of authors are shown to be included in the analysis.

  11. Evaluating the successful implementation of evidence into practice using the PARiHS framework: theoretical and practical challenges

    PubMed Central

    Kitson, Alison L; Rycroft-Malone, Jo; Harvey, Gill; McCormack, Brendan; Seers, Kate; Titchen, Angie

    2008-01-01

    Background The PARiHS framework (Promoting Action on Research Implementation in Health Services) has proved to be a useful practical and conceptual heuristic for many researchers and practitioners in framing their research or knowledge translation endeavours. However, as a conceptual framework it still remains untested and therefore its contribution to the overall development and testing of theory in the field of implementation science is largely unquantified. Discussion This being the case, the paper provides an integrated summary of our conceptual and theoretical thinking so far and introduces a typology (derived from social policy analysis) used to distinguish between the terms conceptual framework, theory and model – important definitional and conceptual issues in trying to refine theoretical and methodological approaches to knowledge translation. Secondly, the paper describes the next phase of our work, in particular concentrating on the conceptual thinking and mapping that has led to the generation of the hypothesis that the PARiHS framework is best utilised as a two-stage process: as a preliminary (diagnostic and evaluative) measure of the elements and sub-elements of evidence (E) and context (C), and then using the aggregated data from these measures to determine the most appropriate facilitation method. The exact nature of the intervention is thus determined by the specific actors in the specific context at a specific time and place. In the process of refining this next phase of our work, we have had to consider the wider issues around the use of theories to inform and shape our research activity; the ongoing challenges of developing robust and sensitive measures; facilitation as an intervention for getting research into practice; and finally to note how the current debates around evidence into practice are adopting wider notions that fit innovations more generally. Summary The paper concludes by suggesting that the future direction of the work on the PARiHS framework is to develop a two-stage diagnostic and evaluative approach, where the intervention is shaped and moulded by the information gathered about the specific situation and from participating stakeholders. In order to expedite the generation of new evidence and testing of emerging theories, we suggest the formation of an international research implementation science collaborative that can systematically collect and analyse experiences of using and testing the PARiHS framework and similar conceptual and theoretical approaches. We also recommend further refinement of the definitions around conceptual framework, theory, and model, suggesting a wider discussion that embraces multiple epistemological and ontological perspectives. PMID:18179688

  12. Theoretical framework for the histone modification network: modifications in the unstructured histone tails form a robust scale-free network.

    PubMed

    Hayashi, Yohei; Senda, Toshiya; Sano, Norihiko; Horikoshi, Masami

    2009-07-01

    A rapid increase in research on the relationship between histone modifications and their subsequent reactions in the nucleus has revealed that the histone modification system is complex, and robust against point mutations. The prevailing theoretical framework (the histone code hypothesis) is inadequate to explain either the complexity or robustness, making the formulation of a new theoretical framework both necessary and desirable. Here, we develop a model of the regulatory network of histone modifications in which we encode histone modifications as nodes and regulatory interactions between histone modifications as links. This network has scale-free properties and subnetworks with a pseudo-mirror symmetry structure, which supports the robustness of the histone modification network. In addition, we show that the unstructured tail regions of histones are suitable for the acquisition of this scale-free property. Our model and related insights provide the first framework for an overall architecture of a histone modification network system, particularly with regard to the structural and functional roles of the unstructured histone tail region. In general, the post-translational "modification webs" of natively unfolded regions (proteins) may function as signal routers for the robust processing of the large amounts of signaling information. PMID:19523169

  13. A large-N expansion based theoretical framework for modeling cold atoms in and out of equilibrium

    NASA Astrophysics Data System (ADS)

    Chien, Chih-Chun; Cooper, Fred; Timmermans, Eddy; Mihaila, Bogdan; Dawson, John

    2014-05-01

    The large-N expansion is a scheme for rearranging Feynman diagrams. Although this technique can be applied to cold atoms with contact interactions, for single-component ultra-cold bosons the leading-order large-N expansion does not reproduce Bogoliubov dispersion in the Bose-Einstein condensation (BEC) phase. However, we prove that the correct vacuum leads to a dispersion resembling Bogoliubov dispersion. Moreover, we have developed a theory, which includes the normal as well as the anomalous Green's functions. This theory, named leading-order auxiliary field theory, is gapless, conserving, and has a second-order phase transition. We also generalize it to describe a two-component Bose gas above its BEC transition temperature. The mixture to phase-separation transition is shown to survive at high temperature in this model without any BEC. Furthermore, the same theoretical framework can be applied to ultra-cold fermions and we found that the BCS-Leggett theory of BCS-BEC crossover can be derived as the leading-order theory from this framework. Importantly, our theoretical framework can be generalized to include time dependence so interesting dynamics in cold atoms could be investigated in a coherent fashion. Supported by US DOE via LANL/LDRD.

  14. A Theoretical Framework for Bilingual Instruction: How Does it Apply to Students in Special Education?

    ERIC Educational Resources Information Center

    Tempes, Fred

    This paper presents a rationale for educating limited English proficiency (LEP) students and considers implications of that rationale for the education of LEP pupils requiring special education. Research in areas of bilingualism, bilingual education, and second language acquisition has provided a basis for an educational framework. A model of…

  15. 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…

  16. 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…

  17. Patterns of Interactions as Affected by Graphing Software: Developing a Theoretical Framework

    ERIC Educational Resources Information Center

    Gibbs, Marie Joubert

    2006-01-01

    This paper extends and develops theories of mathematical learning to provide a framework for the analysis of classroom video data of students working at a computer in a task aimed at increasing understanding of multiple representations of quadratic functions. Student interactions are coded using novel software tools in the process of analysis, and…

  18. A Validation Study of the Leadership Styles of a Holistic Leadership Theoretical Framework

    ERIC Educational Resources Information Center

    Brauckmann, Stefan; Pashiardis, Petros

    2011-01-01

    Purpose: The overall purpose of the European Union-funded Leadership Improvement for Student Achievement (LISA) project was to explore how leadership styles, as conceptualized in the developed dynamic holistic leadership framework, directly or indirectly affect student achievement at the lower secondary level of education in seven European…

  19. Teachers' Stances on Cell Phones in the ESL Classroom: Toward a "Theoretical" Framework

    ERIC Educational Resources Information Center

    Brown, Jeff

    2014-01-01

    In the ongoing and constantly expanding discussion surrounding cell phones in the classroom, a theoretical complement to the practical side of the issue is generally lacking. This is perhaps understandable. Many teachers are still trying to deal with the simple presence of cell phones in the class, and managing a classroom in which the presence…

  20. Predicting Child Abuse Potential: An Empirical Investigation of Two Theoretical Frameworks

    ERIC Educational Resources Information Center

    Begle, Angela Moreland; Dumas, Jean E.; Hanson, Rochelle F.

    2010-01-01

    This study investigated two theoretical risk models predicting child maltreatment potential: (a) Belsky's (1993) developmental-ecological model and (b) the cumulative risk model in a sample of 610 caregivers (49% African American, 46% European American; 53% single) with a child between 3 and 6 years old. Results extend the literature by using a…

  1. Exploring Asynchrony as a Theoretical Framework for Understanding Giftedness: A Case of Cognitive Dissonance?

    ERIC Educational Resources Information Center

    Andronaco, Julie A.; Shute, Rosalyn; McLachlan, Angus

    2014-01-01

    Asynchrony is a theoretical construct that views the intellectually gifted child as inherently vulnerable because of disparities arising from the mismatch between his or her chronological age and mental age. Such disparities, for example, between wanting to belong but being intellectually out of step with peers, are said to give rise to a…

  2. Framework of a Decision-Theoretic Tutoring System for Learning of Mechanics.

    ERIC Educational Resources Information Center

    Pek, Peng-Kiat; Poh, Kim-Leng

    2000-01-01

    Presents the application of decision-theoretic technique to a computer-based tutoring system for elementary mechanics. Uses sound probabilistic reasoning and a student model to identify learners' misconceptions. Focuses on the integration of Bayesian belief networks, item response theory, decision analysis, and database management systems in…

  3. An Examination of Physical Education Teacher Motivation from a Self-Determination Theoretical Framework

    ERIC Educational Resources Information Center

    Carson, Russell L.; Chase, Melissa A.

    2009-01-01

    Background: The motivation of physical education (PE) teachers has received precious little attention over the years. Self-determination theory (SDT) is a salient theoretical model for understanding motivation, and posits that self-determined motivation (i.e., intrinsic motivation) stems from the perceived fulfillment of three psychological needs:…

  4. Theoretical Perspectives on the Education of Choral Conductors: A Suggested Framework

    ERIC Educational Resources Information Center

    Varvarigou, Maria; Durrant, Colin

    2011-01-01

    This paper presents theoretical perspectives for choral conducting education. A wide range of related literature on choral practice and education in higher education contexts, as well as training in the workplace is reviewed. Whilst various attributes for effective choral conducting practice have been identified by research studies, there has been…

  5. Half-Lives for Proton Emission, Alpha Decay, Cluster Radioactivity, and Cold Fission Processes Calculated in a Unified Theoretical Framework

    NASA Astrophysics Data System (ADS)

    Duarte, S. B.; Tavares, O. A. P.; Guzmán, F.; Dimarco, A.; García, F.; Rodríguez, O.; Gonçalves, M.

    2002-03-01

    Half-life values of spontaneous nuclear decay processes are presented in the framework of the effective liquid drop model (ELDM) using the combination of varying mass asymmetry shape description for the mass transfer (VMAS) and Werner-Wheeler's inertia coefficient (WW). The calculated half lives of ground-state to ground-state transitions for proton emission, alpha decay, cluster radioactivity, and cold fission processes are compared with experimental data. These comparisons show that the ELDM is a very efficient model to describe these different decay processes in a same, unified, theoretical framework. A table listing the predicted half-life values, ?c, is presented for all possible cases of spontaneous nuclear breakup such that -7.30?log10?c [s]?27.50 and log10(?/?c)>-17.0, where ? is the total half life of the parent nucleus.

  6. A theoretical framework for the regulation of Shh morphogen-controlled gene expression

    PubMed Central

    Cohen, Michael; Page, Karen M.; Perez-Carrasco, Ruben; Barnes, Chris P.; Briscoe, James

    2014-01-01

    How morphogen gradients govern the pattern of gene expression in developing tissues is not well understood. Here, we describe a statistical thermodynamic model of gene regulation that combines the activity of a morphogen with the transcriptional network it controls. Using Sonic hedgehog (Shh) patterning of the ventral neural tube as an example, we show that the framework can be used together with the principled parameter selection technique of approximate Bayesian computation to obtain a dynamical model that accurately predicts tissue patterning. The analysis indicates that, for each target gene regulated by Gli, which is the transcriptional effector of Shh signalling, there is a neutral point in the gradient, either side of which altering the Gli binding affinity has opposite effects on gene expression. This explains recent counterintuitive experimental observations. The approach is broadly applicable and provides a unifying framework to explain the temporospatial pattern of morphogen-regulated gene expression. PMID:25294939

  7. Assigning Function to Adult-Born Neurons: A Theoretical Framework for Characterizing Neural Manipulation of Learning

    PubMed Central

    Hersman, Sarah; Rodriguez Barrera, Vanessa; Fanselow, Michael

    2016-01-01

    Neuroscientists are concerned with neural processes or computations, but these may not be directly observable. In the field of learning, a behavioral procedure is observed to lead to performance outcomes, but differing inferences on underlying internal processes can lead to difficulties in interpreting conflicting results. An example of this challenge is how many functions have been attributed to adult-born granule cells in the dentate gyrus. Some of these functions were suggested by computational models of the properties of these neurons, while others were hypothesized after manipulations of adult-born neurons resulted in changes to behavioral metrics. This review seeks to provide a framework, based in learning theory classification of behavioral procedures, of the processes that may be underlying behavioral results after manipulating procedure and observing performance. We propose that this framework can serve to clarify experimental findings on adult-born neurons as well as other classes of neural manipulations and their effects on behavior. PMID:26778981

  8. A theoretical framework for antigay aggression: Review of established and hypothesized effects within the context of the general aggression model⋆

    PubMed Central

    Parrott, Dominic J.

    2008-01-01

    Theory and research on antigay aggression has identified different motives that facilitate aggression based on sexual orientation. However, the individual and situational determinants of antigay aggression associated with these motivations have yet to be organized within a single theoretical framework. This limits researchers’ ability to organize existing knowledge, link that knowledge with related aggression theory, and guide the application of new findings. To address these limitations, this article argues for the use of an existing conceptual framework to guide thinking and generate new research in this area of study. Contemporary theories of antigay aggression, and empirical support for these theories, are reviewed and interpreted within the unifying framework of the general aggression model [Anderson, C.A. & Bushman, B.J. (2002). Human aggression. Annual Review of Psychology, 53, 27–51.]. It is concluded that this conceptual framework will facilitate investigation of individual and situational risk factors that may contribute to antigay aggression and guide development of individual-level intervention. PMID:18355952

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

    PubMed

    Kensche, M; Schweiger, U

    2015-07-01

    Therapists have to deal with verbal systems and often work with verbal exchange. Therefore, a psychological theory is required, which teaches the therapist how to accomplish this task. The BRT is a theory of human language and cognition that explains how people use their verbal behavior as stimuli in their interrelations and how they act and react, based on the resulting relationships. This behavior is learned very early in the course of language acquisition and functions as a generalized operant. A prerequisite for this is the ability of people to undergo mental simulation. This enables them to construct diverse relational frameworks between individual stimuli. Without relational frameworks, people cannot function. The ability to establish a relational framework is a prerequisite for the formation of rule-governed behavior. Rule-governed behavior economizes complex decision processes, creates interpersonal security and enables dealing with events before they take place. On the other hand, the same properties that enable people to solve problems effectively can also contribute to rigid adherence to rules and experience avoidance. Relational frameworks, once established, outweigh other sources of behavioral regulation. Thus, it can become the basis of psychopathology. Poor contextual control makes it difficult for people to devote flexible, focused and voluntary attention to the present and align their actions with the immediate present. Contextual psychotherapy methods that are based on the BRT start precisely at this point: Targeted establishment of new contingencies in the therapeutic interaction through systematic strengthening of metacognitive mode and through the establishment of new rules that make possible a change in the rule-governed behavior enable undermining of dysfunctional rule-governed behavior and build up desirable behavior. This allows any therapeutic process to be more effective--regardless of the patient's expressed symptoms. PMID:26158614

  10. A theoretical framework for studying the electromagnetic stimulation of nervous tissue.

    PubMed

    Accoto, D; Valentini, S; Portaccio, I; Guglielmelli, E

    2015-08-01

    In this paper we present a model for calculating the electric field, and its spatial derivatives, produced by arbitrarily shaped, oriented and placed coils carrying time-varying currents. The model has been validated by comparing its results with those obtained using FEM simulations. The model provides a simple and fast computation framework to investigate the electromagnetic stimulation of neural tissues. Some example applications are also provided. PMID:26736697

  11. Integrating Sediment Connectivity into Water Resources Management Trough a Graph Theoretic, Stochastic Modeling Framework.

    NASA Astrophysics Data System (ADS)

    Schmitt, R. J. P.; Castelletti, A.; Bizzi, S.

    2014-12-01

    Understanding sediment transport processes at the river basin scale, their temporal spectra and spatial patterns is key to identify and minimize morphologic risks associated to channel adjustments processes. This work contributes a stochastic framework for modeling bed-load connectivity based on recent advances in the field (e.g., Bizzi & Lerner, 2013; Czubas & Foufoulas-Georgiu, 2014). It presents river managers with novel indicators from reach scale vulnerability to channel adjustment in large river networks with sparse hydrologic and sediment observations. The framework comprises three steps. First, based on a distributed hydrological model and remotely sensed information, the framework identifies a representative grain size class for each reach. Second, sediment residence time distributions are calculated for each reach in a Monte-Carlo approach applying standard sediment transport equations driven by local hydraulic conditions. Third, a network analysis defines the up- and downstream connectivity for various travel times resulting in characteristic up/downstream connectivity signatures for each reach. Channel vulnerability indicators quantify the imbalance between up/downstream connectivity for each travel time domain, representing process dependent latency of morphologic response. Last, based on the stochastic core of the model, a sensitivity analysis identifies drivers of change and major sources of uncertainty in order to target key detrimental processes and to guide effective gathering of additional data. The application, limitation and integration into a decision analytic framework is demonstrated for a major part of the Red River Basin in Northern Vietnam (179.000 km2). Here, a plethora of anthropic alterations ranging from large reservoir construction to land-use changes results in major downstream deterioration and calls for deriving concerted sediment management strategies to mitigate current and limit future morphologic alterations.

  12. On building methodological and theoretical frameworks to examine the interrelationships between environmental change and armed conflict

    NASA Astrophysics Data System (ADS)

    Van Den Hoek, J.

    2014-12-01

    Relationships between environmental change and armed conflict have long been studied. Sometimes referred to as 'warfare' or 'conflict' ecology, much of this scholarship has come in response to local-level perceptions of landscape or livelihood changes that result from regional armed conflict. However, such studies have, first, typically focused on spatiotemporally acute and readily detectable environmental change, like deforestation, to the exclusion of protracted and more subtle environmental changes, like agricultural degradation; second, been limited to situational conflicts or circumstances, thereby inhibiting broader theoretical development; and, third, often only considered the environmental consequences rather than the environmental or climatic circumstances that may contribute to conflict. As a result, there is little opportunity for methodological or theoretical cohesion between studies. In this presentation, I synthesize findings from three case studies examining the interrelationships between agricultural change and armed conflict in the semi-arid landscapes of northwest Pakistan, Palestine, and southern Syria. Using coarse through very high resolution remotely sensed imagery, socio-economic and demographic data, conflict databases, open-source programming, and building on theoretical underpinnings of political ecology and conflict studies, I present methods and modeling approaches that aid in overcoming data scarcity and disparity between scales of analysis and integrate environmental and conflict data in spatiotemporally explicit ways. Results from these case studies illuminate the interrelationships between both protracted and acute agricultural change and armed conflict, and have broad relevance for understanding the means by which environment, conflict, and livelihoods are linked, a nexus that will only become tighter with the advance of global climate change.

  13. On the presence of electric currents in the solar atmosphere. I - A theoretical framework

    NASA Technical Reports Server (NTRS)

    Hagyard, M.; Low, B. C.; Tandberg-Hanssen, E.

    1981-01-01

    The general magnetic field above the solar photosphere is divided by an elementary analysis based on Ampere's law into two parts: a potential field due to electric currents below the photosphere and a field produced by electric currents above the photosphere combined with the induced mirror currents. The latter, by symmetry, has a set of field lines lying in the plane taken to be the photosphere which may be constructed from given vector magnetograph measurements. These field lines also represent all the information on the electric currents above the photosphere that a magnetograph can provide. Theoretical illustrations are given, and implications for data analysis are discussed.

  14. Dynamic decision making for dam-break emergency management - Part 1: Theoretical framework

    NASA Astrophysics Data System (ADS)

    Peng, M.; Zhang, L. M.

    2013-02-01

    An evacuation decision for dam breaks is a very serious issue. A late decision may lead to loss of lives and properties, but a very early evacuation will incur unnecessary expenses. This paper presents a risk-based framework of dynamic decision making for dam-break emergency management (DYDEM). The dam-break emergency management in both time scale and space scale is introduced first to define the dynamic decision problem. The probability of dam failure is taken as a stochastic process and estimated using a time-series analysis method. The flood consequences are taken as functions of warning time and evaluated with a human risk analysis model (HURAM) based on Bayesian networks. A decision criterion is suggested to decide whether to evacuate the population at risk (PAR) or to delay the decision. The optimum time for evacuating the PAR is obtained by minimizing the expected total loss, which integrates the time-related probabilities and flood consequences. When a delayed decision is chosen, the decision making can be updated with available new information. A specific dam-break case study is presented in a companion paper to illustrate the application of this framework to complex dam-breaching problems.

  15. Global sensitivity analysis in hydrological modeling: Review of concepts, methods, theoretical framework, and applications

    NASA Astrophysics Data System (ADS)

    Song, Xiaomeng; Zhang, Jianyun; Zhan, Chesheng; Xuan, Yunqing; Ye, Ming; Xu, Chonggang

    2015-04-01

    Sensitivity analysis (SA) aims to identify the key parameters that affect model performance and it plays important roles in model parameterization, calibration, optimization, and uncertainty quantification. However, the increasing complexity of hydrological models means that a large number of parameters need to be estimated. To better understand how these complex models work, efficient SA methods should be applied before the application of hydrological modeling. This study provides a comprehensive review of global SA methods in the field of hydrological modeling. The common definitions of SA and the typical categories of SA methods are described. A wide variety of global SA methods have been introduced to provide a more efficient evaluation framework for hydrological modeling. We review, analyze, and categorize research into global SA methods and their applications, with an emphasis on the research accomplished in the hydrological modeling field. The advantages and disadvantages are also discussed and summarized. An application framework and the typical practical steps involved in SA for hydrological modeling are outlined. Further discussions cover several important and often overlooked topics, including the relationship between parameter identification, uncertainty analysis, and optimization in hydrological modeling, how to deal with correlated parameters, and time-varying SA. Finally, some conclusions and guidance recommendations on SA in hydrological modeling are provided, as well as a list of important future research directions that may facilitate more robust analyses when assessing hydrological modeling performance.

  16. Theory of mind and paranoia in schizophrenia: a game theoretical investigation framework.

    PubMed

    Chan, Kevin K S; Chen, Eric Y H

    2011-11-01

    INTRODUCTION. Ample evidence already shows that theory of mind (ToM) is impaired in people with schizophrenia. Our aim was to critically review this literature. METHOD. We completed a selected review of the research literature on ToM in schizophrenia. RESULTS. Gaps in ToM research were identified. A specific relationship between impaired ToM and paranoid delusions, although intuitively reasonable from a theoretical basis, has only been demonstrated in a few studies. Psychometric properties of ToM tasks employed in these studies may be a confounding factor in drawing conclusions about the relationship. Because most ToM measures have focused on the third-person perspective, participants are not actively interacting. The tasks fail to capture the cognitive demands faced by individuals in real-life situations, and, in effect, are not a direct measure of ToM. CONCLUSIONS. Potential research areas are discussed. Since game theoretical paradigms require the direct involvement of the first person and situate the participant's interpersonal reasoning within an interactive context, they provide more ecologically valid experimental platforms than conventional questionnaire measures to assess ToM in schizophrenia research. PMID:21563010

  17. Physicians' use of medical knowledge resources: preliminary theoretical framework and findings.

    PubMed

    Curley, S P; Connelly, D P; Rich, E C

    1990-01-01

    The recurring decision of selecting among potential knowledge resources was modeled as a cost-benefit tradeoff, with associated observable features. Internal medicine and community family practice physicians (n = 228) completed a self-administered questionnaire designed to elicit reported use and cost-benefit features of nine knowledge resources. The subjects reported most frequent use of clinical colleagues, intermediate use of textbooks and journals, and least use of indexing systems. Resources' benefit-related qualities (extensiveness and credibility) were not related to reported use. In contrast, the model's access cost variables (availability, searchability, understandability, and clinical applicability) were significantly related to use. Results were generally favorable to the model's framework of knowledge resource selection. Multiple linear regression analysis suggested that physicians' use of clinical knowledge resources could be described by the physician's level of training, availability, applicability, and the resource medium (colleague, index, or text/journal). PMID:2122168

  18. Transition Services for DHH Adolescents and Young Adults With Disabilities: Challenges and Theoretical Frameworks.

    PubMed

    Luft, Pamela

    2015-01-01

    Deaf and hard of hearing (DHH) adolescents and young adults with disabilities (DWD) are a highly diverse group who may also demonstrate a range of functional limitations. These present unique challenges to professional efforts to provide high-quality transition services. Despite these issues, a majority of this population has cognitive abilities within the typical range, and therefore, their transition expectations should be commensurately high in comparison to those of their DHH peers. Research-based transition practices offer a range of interventions, and although none have been validated with DHH or DWD students, several provide important foundational learning opportunities. Yet their implementation will require modifications with programming and expertise beyond what is available in most school districts. Use of a multilevel, ecological framework and person-centered planning offers systematic strategies for increasing access to transition resources and supports to address these unique needs and lead to successful adulthood. PMID:26497077

  19. The Unblocking Leadership for Effectiveness of Teachers as Knowledge Staff: A Theoretical Framework for School Management

    ERIC Educational Resources Information Center

    Ozmusul, Mustafa

    2015-01-01

    When investigating the literature, it seems that little attention has been paid to what kind of leadership is needed for improving teacher effectiveness in terms of focusing on the obstacles that teachers face. Therefore, this study aims mainly to explore the obstacles that hinder the teachers when they do best in terms of receiving autonomy,…

  20. Responsive Feeding Is Embedded in a Theoretical Framework of Responsive Parenting123

    PubMed Central

    Black, Maureen M.; Aboud, Frances E.

    2011-01-01

    Children throughout the world are confronted with growth problems ranging from underweight and stunting to overweight and obesity. The development of healthy eating behaviors depends on both healthy food and responsive parenting behaviors. With origins from anthropology, psychology, and nutrition, responsive parenting reflects reciprocity between child and caregiver, conceptualized as a 4-step mutually responsive process: 1) the caregiver creates a routine, structure, expectations, and emotional context that promote interaction; 2) the child responds and signals to the caregiver; 3) the caregiver responds promptly in a manner that is emotionally supportive, contingent, and developmentally appropriate; and 4) the child experiences predictable responses. This paper examines evidence for the practice and developmental benefits of responsive parenting with a view to providing a theoretical basis for responsive feeding. Recommendations are made that future efforts to promote healthy growth and to prevent underweight and overweight among young children incorporate and evaluate responsive feeding. PMID:21270366

  1. Predicting child abuse potential: An empirical investigation of two theoretical frameworks

    PubMed Central

    Begle, Angela Moreland; Dumas, Jean E.; Hanson, Rochelle F.

    2010-01-01

    This study investigated two theoretical risk models predicting child maltreatment potential: 1) Belsky’s (1993) developmental-ecological model and 2) the cumulative risk model in a sample of 610 caregivers (49% African American, 46% European American; 53% single) with a child between 3 and 6 years old. Results extend the literature by using a widely accepted and valid risk instrument (i.e., CAPI) rather than occurrence rates (e.g., reports to child protective services, observations). Results indicated Belsky’s (1993) developmental-ecological model, in which risk markers were organized into three separate conceptual domains, provided a poor fit to the data. In contrast, the cumulative risk model, which included the accumulation of risk markers, was significant in predicting child abuse potential. PMID:20390812

  2. Understanding the Theoretical Framework of Technological Pedagogical Content Knowledge: A Collaborative Self-Study to Understand Teaching Practice and Aspects of Knowledge

    ERIC Educational Resources Information Center

    Fransson, Goran; Holmberg, Jorgen

    2012-01-01

    This paper describes a self-study research project that focused on our experiences when planning, teaching, and evaluating a course in initial teacher education. The theoretical framework of technological pedagogical content knowledge (TPACK) was used as a conceptual structure for the self-study. Our understanding of the framework in relation to…

  3. Haemoglobin transfusion threshold in very preterm newborns: a theoretical framework derived from prevailing oxygen physiology.

    PubMed

    Andersen, C C; Stark, M J

    2012-01-01

    The overwhelming majority of very preterm newborns receive at least one transfusion during their in hospital stay. However, despite two recent randomised trials, the appropriate haemoglobin transfusion threshold in these high risk infants remains unclear. Typically, clinicians consider gestation, chronologic age and illness severity in order to determine the need for transfusion. There is, however, no simple way to balance these heterogeneous variables in order to arrive at a transfusion threshold without considering the prevailing oxygen physiology. This is particularly important during the transition to extra-uterine life, a time when the risk of brain injury is highest. We hypothesise that dysregulated cerebral oxygen handling, characterised by restricted oxygen consumption from suboptimal oxygen delivery increases the risk of hypoxic ischaemic brain injury in very preterm newborns and is the single common patho-physiologic process underlying early acquired brain injury in the preterm newborn. Our proposed framework, based on the physiology of oxygen handling, considers the prevailing oxygen kinetics in the very preterm newborn as a means of deriving the appropriate Hb transfusion threshold thereby balancing oxygen delivery and consumption and avoiding hypoxic ischaemic early brain injury. Manipulation of the oxygen delivery equation, with consideration of the likely chronologic changes to cardiac output in particular, permit derivation of a transfusion threshold in the first week of life and represents a novel therapeutic intervention aimed solely at prevention of early acquired brain injury and its associated long term neuro-developmental burden. PMID:22014757

  4. Deep Brain Stimulation for Obesity: From a Theoretical Framework to Practical Application.

    PubMed

    Nangunoori, Raj K; Tomycz, Nestor D; Oh, Michael Y; Whiting, Donald M

    2016-01-01

    Obesity remains a pervasive global health problem. While there are a number of nonsurgical and surgical options for treatment, the incidence of obesity continues to increase at an alarming rate. The inability to curtail the growing rise of the obesity epidemic may be related to a combination of increased food availability and palatability. Research into feeding behavior has yielded a number of insights into the homeostatic and reward mechanisms that govern feeding. However, there remains a gap between laboratory investigations of feeding physiology in animals and translation into meaningful treatment options for humans. In addition, laboratory investigation may not be able to recapitulate all aspects of human food consumption. In a landmark pilot study of deep brain stimulation (DBS) of the lateral hypothalamic area for obesity, we found that there was an increase in resting metabolic rate as well as a decreased urge to eat. In this review, the authors will review some of the work relating to feeding physiology and research surrounding two nodes involved in feeding homeostasis, nucleus accumbens (NAc) and hypothalamus, and use this to provide a framework for future investigations of DBS as a viable therapeutic modality for obesity. PMID:26819774

  5. Deep Brain Stimulation for Obesity: From a Theoretical Framework to Practical Application

    PubMed Central

    Nangunoori, Raj K.; Tomycz, Nestor D.; Oh, Michael Y.; Whiting, Donald M.

    2016-01-01

    Obesity remains a pervasive global health problem. While there are a number of nonsurgical and surgical options for treatment, the incidence of obesity continues to increase at an alarming rate. The inability to curtail the growing rise of the obesity epidemic may be related to a combination of increased food availability and palatability. Research into feeding behavior has yielded a number of insights into the homeostatic and reward mechanisms that govern feeding. However, there remains a gap between laboratory investigations of feeding physiology in animals and translation into meaningful treatment options for humans. In addition, laboratory investigation may not be able to recapitulate all aspects of human food consumption. In a landmark pilot study of deep brain stimulation (DBS) of the lateral hypothalamic area for obesity, we found that there was an increase in resting metabolic rate as well as a decreased urge to eat. In this review, the authors will review some of the work relating to feeding physiology and research surrounding two nodes involved in feeding homeostasis, nucleus accumbens (NAc) and hypothalamus, and use this to provide a framework for future investigations of DBS as a viable therapeutic modality for obesity. PMID:26819774

  6. The Promoting Effective Advance Care for Elders (PEACE) randomized pilot study: theoretical framework and study design.

    PubMed

    Allen, Kyle R; Hazelett, Susan E; Radwany, Steven; Ertle, Denise; Fosnight, Susan M; Moore, Pamela S

    2012-04-01

    Practice guidelines are available for hospice and palliative medicine specialists and geriatricians. However, these guidelines do not adequately address the needs of patients who straddle the 2 specialties: homebound chronically ill patients. The purpose of this article is to describe the theoretical basis for the Promoting Effective Advance Care for Elders (PEACE) randomized pilot study. PEACE is an ongoing 2-group randomized pilot study (n=80) to test an in-home interdisciplinary care management intervention that combines palliative care approaches to symptom management, psychosocial and emotional support, and advance care planning with geriatric medicine approaches to optimizing function and addressing polypharmacy. The population comprises new enrollees into PASSPORT, Ohio's community-based, long-term care Medicaid waiver program. All PASSPORT enrollees have geriatric/palliative care crossover needs because they are nursing home eligible. The intervention is based on Wagner's Chronic Care Model and includes comprehensive interdisciplinary care management for these low-income frail elders with chronic illnesses, uses evidence-based protocols, emphasizes patient activation, and integrates with community-based long-term care and other community agencies. Our model, with its standardized, evidence-based medical and psychosocial intervention protocols, will transport easily to other sites that are interested in optimizing outcomes for community-based, chronically ill older adults. PMID:22088165

  7. Empirical social-ecological system analysis: from theoretical framework to latent variable structural equation model.

    PubMed

    Asah, Stanley Tanyi

    2008-12-01

    The social-ecological system (SES) approach to natural resource management holds enormous promise towards achieving sustainability. Despite this promise, social-ecological interactions are complex and elusive; they require simplification to guide effective application of the SES approach. The complex, adaptive and place-specific nature of human-environment interactions impedes determination of state and trends in SES parameters of interest to managers and policy makers. Based on a rigorously developed systemic theoretical model, this paper integrates field observations, interviews, surveys, and latent variable modeling to illustrate the development of simplified and easily interpretable indicators of the state of, and trends in, relevant SES processes. Social-agricultural interactions in the Logone floodplain, in the Lake Chad basin, served as case study. This approach is found to generate simplified determinants of the state of SESs, easily communicable across the array of stakeholders common in human-environment interactions. The approach proves to be useful for monitoring SESs, guiding interventions, and assessing the effectiveness of interventions. It incorporates real time responses to biophysical change in understanding coarse scale processes within which finer scales are embedded. This paper emphasizes the importance of merging quantitative and qualitative methods for effective monitoring and assessment of SESs. PMID:18773239

  8. Estimating vocal repertoire size is like collecting coupons: a theoretical framework with heterogeneity in signal abundance.

    PubMed

    Kershenbaum, Arik; Freeberg, Todd M; Gammon, David E

    2015-05-21

    Vocal repertoire size is an important behavioural measure in songbirds and mammals with complex vocal communication systems, and has traditionally been used as an indicator of individual fitness, cognitive ability, and social structure. Estimates of asymptotic repertoire size have typically been made using curve fitting techniques. However, the exponential model usually applied in these techniques has never been provided with a theoretical justification based on probability theory, and the model has led to inaccurate estimates. We derived the precise expression for the expected number of distinct signal types observed for a fixed sampling effort: a variation of what is known in the statistical literature as the "Coupon Collector?s problem". We used empirical data from three species (northern mockingbird, Carolina chickadee, and rock hyrax) to assess the performance of the Coupon Collector model compared to commonly used techniques, such as exponential fitting and repertoire enumeration, and also tested the different models against simulated artificial data sets with the statistical properties of the empirical data. We found that when signal probabilities are dissimilar, the Coupon Collector model provides far more accurate estimates of repertoire size than traditional techniques. Enumeration and exponential curve fitting greatly underestimated repertoire size, despite appearing to have reached saturation. Application of the Coupon Collector model can generate more accurate estimates of repertoire size than the commonly used exponential model of repertoire discovery, and could go a long way towards re-establishing repertoire size as a useful indicator in animal communication research. PMID:25791282

  9. Theoretical framework to analyze searches for hidden light gauge bosons in electron scattering fixed target experiments

    NASA Astrophysics Data System (ADS)

    Beranek, T.; Merkel, H.; Vanderhaeghen, M.

    2013-07-01

    Motivated by anomalies in cosmic ray observations and by attempts to solve questions of the Standard Model of particle physics like the (g-2)? discrepancy, U(1) extensions of the Standard Model have been proposed in recent years. Such U(1) extensions allow for the interaction of dark matter by exchange of a photonlike massive force carrier ?' not included in the Standard Model. In order to search for ?' bosons, various experimental programs have been started. One approach is the dedicated search at fixed-target experiments at modest energies as performed at microtron (MAMI) or at the Jefferson Lab. In these experiments the process e(A,Z)?e(A,Z)l+l- is investigated, and a search for a very narrow resonance in the invariant mass distribution of the l+l- pair is performed. In this work we analyze this process in terms of signal and background in order to describe existing data obtained by the A1 experiment at MAMI with the aim to give accurate predictions for exclusion limits in the ?' parameter space. We present a detailed theoretical analysis of the cross sections entering in the description of such processes.

  10. A theoretical framework for evaluating analytical digestion methods for poorly soluble particulate beryllium.

    PubMed

    Stefaniak, Aleksandr B; Brink, Christopher A; Dickerson, Robert M; Day, Gregory A; Brisson, Michael J; Hoover, Mark D; Scripsick, Ronald C

    2007-04-01

    Complete digestion of all chemical forms and sizes of particulate analytes in environmental samples is usually necessary to obtain accurate results with atomic spectroscopy. In the current study, we investigate the physicochemical properties of beryllium particles likely to be encountered in samples collected from different occupational environments and present a hypothesis that a dissolution theory can be used as a conceptual framework to guide development of strategies for digestion procedures. For monodisperse single-chemical constituent primary particles, such as those encountered when handling some types of beryllium oxide (BeO) powder, theory predicts that a digestion procedure is sufficient when it completely dissolves all primary particles, independent of cluster size. For polydisperse single-chemical constituent particles, such as those encountered during the handling of some types of beryllium metal powder, theory predicts that a digestion procedure is sufficient only when it completely dissolves the largest particle in the sample. For samples with unknown or multi-chemical constituent particles and with particles having undefined sizes, e.g., fume emissions from a copper-beryllium alloy furnace operation or dust from a beryl ore crushing operation, a surface area-limited and single-constituent-dependent dissolution theory may not predict complete dissolution, thereby requiring non-routine robust treatment procedures with post-digestion filtration, followed by examination of residual particulate material. Additionally, for beryllium, and likely other poorly soluble materials, particulate reference materials of various chemical forms and size distributions are needed to better evaluate and harmonize analytical digestion procedures. Figure Generation of aerosol particles during machining of beryllium oxide. PMID:17124574

  11. On a New Theoretical Framework for RR Lyrae Stars. I. The Metallicity Dependence

    NASA Astrophysics Data System (ADS)

    Marconi, M.; Coppola, G.; Bono, G.; Braga, V.; Pietrinferni, A.; Buonanno, R.; Castellani, M.; Musella, I.; Ripepi, V.; Stellingwerf, R. F.

    2015-07-01

    We present new nonlinear, time-dependent convective hydrodynamical models of RR Lyrae stars computed assuming a constant helium-to-metal enrichment ratio and a broad range in metal abundances (Z = 0.0001-0.02). The stellar masses and luminosities adopted to construct the pulsation models were fixed according to detailed central He-burning horizontal-branch evolutionary models. The pulsation models cover a broad range in stellar luminosity and effective temperatures and the modal stability is investigated for both fundamental (FU) and first overtone polsators (FOs). We predict the topology of the instability strip (IS) as a function of the metal content and new analytical relations for the edges of the IS in the observational plane. Moreover, a new analytical relation to constrain the pulsation mass of double pulsators as a function of the period ratio and the metal content is provided. We derive new Period-Radius-Metallicity relations for FU and FO pulsators. They agree quite well with similar empirical and theoretical relations in the literature. From the predicted bolometric light curves, transformed into optical (UBVRI) and near-infrared (NIR; JHK) bands, we compute the intensity-averaged mean magnitudes along the entire pulsation cycle and in turn new and homogenous metal-dependent (RIJHK) Period-Luminosity relations. Moreover, we compute new dual and triple-band optical, optical-NIR, and NIR Period-Wesenheit-Metallicity relations. Interestingly, we find that the optical Period-W(V, B-V) is independent of the metal content and that the accuracy of individual distances is a balance between the adopted diagnostics and the precision of photometric and spectroscopic data sets.

  12. [Marxism as a theoretical and methodological framework in collective health: implications for systematic review and synthesis of evidence].

    PubMed

    Soares, Cassia Baldini; Campos, Celia Maria Sivalli; Yonekura, Tatiana

    2013-12-01

    In this study, we discuss the integration in systematic reviews of research developed from a Marxist perspective of knowledge production and their results as evidence in healthcare. The study objectives are to review the assumptions of dialectical and historical materialism (DHM) and discuss the implications of dialectics for a literature review and the synthesis of evidence. DHM is a powerful framework for knowledge generation and transformation of policies and practices in healthcare. It assumes that social contradictions underlie the health-disease process, the fundamental theoretical construction in the field of collective health. Currently, we observe a considerable influence of the critical paradigm, of Marxist origin, in the construction of knowledge in health. Studies based on this critical paradigm incorporate complex methods, which are inherent to the guidelines of dialect, to identify the object and arrive at results that constitute evidence in healthcare. Systematic reviews should address the methodological difficulties associated with entirely integrating these results to healthcare. PMID:24626368

  13. Algebraic Structures, Physics and Geometry from a Unified Field Theoretical Framework

    NASA Astrophysics Data System (ADS)

    Cirilo-Lombardo, Diego Julio

    2015-10-01

    Starting from a Unified Field Theory (UFT) proposed previously by the author, the possible fermionic representations arising from the same spacetime are considered from the algebraic and geometrical viewpoint. We specifically demonstrate in this UFT general context that the underlying basis of the single geometrical structure P( G, M) (the principal fiber bundle over the real spacetime manifold M with structural group G) reflecting the symmetries of the different fields carry naturally a biquaternionic structure instead of a complex one. This fact allows us to analyze algebraically and to interpret physically in a straighforward way the Majorana and Dirac representations and the relation of such structures with the spacetime signature and non-hermitian (CP) dynamic operators. Also, from the underlying structure of the tangent space, the existence of hidden (super) symmetries and the possibility of supersymmetric extensions of these UFT models are given showing that Rothstein's theorem is incomplete for that description. The importance of the Clifford algebras in the description of all symmetries, mainly the interaction of gravity with the other fields, is briefly discussed.

  14. Neurophysiological and neurocognitive mechanisms underlying the effects of yoga-based practices: towards a comprehensive theoretical framework

    PubMed Central

    Schmalzl, Laura; Powers, Chivon; Henje Blom, Eva

    2015-01-01

    During recent decades numerous yoga-based practices (YBP) have emerged in the West, with their aims ranging from fitness gains to therapeutic benefits and spiritual development. Yoga is also beginning to spark growing interest within the scientific community, and yoga-based interventions have been associated with measureable changes in physiological parameters, perceived emotional states, and cognitive functioning. YBP typically involve a combination of postures or movement sequences, conscious regulation of the breath, and various techniques to improve attentional focus. However, so far little if any research has attempted to deconstruct the role of these different component parts in order to better understand their respective contribution to the effects of YBP. A clear operational definition of yoga-based therapeutic interventions for scientific purposes, as well as a comprehensive theoretical framework from which testable hypotheses can be formulated, is therefore needed. Here we propose such a framework, and outline the bottom-up neurophysiological and top-down neurocognitive mechanisms hypothesized to be at play in YBP. PMID:26005409

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

    PubMed

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

    2015-01-01

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

  16. Understanding the Canadian adult CT head rule trial: use of the theoretical domains framework for process evaluation

    PubMed Central

    2013-01-01

    Background The Canadian CT Head Rule was prospectively derived and validated to assist clinicians with diagnostic decision-making regarding the use of computed tomography (CT) in adult patients with minor head injury. A recent intervention trial failed to demonstrate a decrease in the rate of head CTs following implementation of the rule in Canadian emergency departments. Yet, the same intervention, which included a one-hour educational session and reminders at the point of requisition, was successful in reducing cervical spine imaging rates in the same emergency departments. The reason for the varied effect of the intervention across these two behaviours is unclear. There is an increasing appreciation for the use of theory to conduct process evaluations to better understand how strategies are linked with outcomes in implementation trials. The Theoretical Domains Framework (TDF) has been used to explore health professional behaviour and to design behaviour change interventions but, to date, has not been used to guide a theory-based process evaluation. In this proof of concept study, we explored whether the TDF could be used to guide a retrospective process evaluation to better understand emergency physicians’ responses to the interventions employed in the Canadian CT Head Rule trial. Methods A semi-structured interview guide, based on the 12 domains from the TDF, was used to conduct telephone interviews with project leads and physician participants from the intervention sites in the Canadian CT Head Rule trial. Two reviewers independently coded the anonymised interview transcripts using the TDF as a coding framework. Relevant domains were identified by: the presence of conflicting beliefs within a domain; the frequency of beliefs; and the likely strength of the impact of a belief on the behaviour. Results Eight physicians from four of the intervention sites in the Canadian CT Head Rule trial participated in the interviews. Barriers likely to assist with understanding physicians’ responses to the intervention in the trial were identified in six of the theoretical domains: beliefs about consequences; beliefs about capabilities; behavioural regulation; memory, attention and decision processes; environmental context and resources; and social influences. Despite knowledge that the Canadian CT Head Rule was highly sensitive and reliable for identifying clinically important brain injuries and strong beliefs about the benefits for using the rule, a number of barriers were identified that may have prevented physicians from consistently applying the rule. Conclusion This proof of concept study demonstrates the use of the TDF as a guiding framework to design a retrospective theory-based process evaluation. There is a need for further development and testing of methods for using the TDF to guide theory-based process evaluations running alongside behaviour change intervention trials. PMID:23433082

  17. Would the solvent effect be the main cause of band shift in the theoretical absorption spectrum of large lanthanide complexes?

    NASA Astrophysics Data System (ADS)

    Freire, Ricardo O.; Rodrigues, Nailton M.; Rocha, Gerd B.; Gimenez, Iara F.; da Costa Junior, Nivan B.

    2011-06-01

    As most reactions take place in solution, the study of solvent effects on relevant molecular properties - either by experimental or theoretical methods - is crucial for the design of new processes and prediction of technological properties. In spite of this, only few works focusing the influence of the solvent nature specifically on the spectroscopic properties of lanthanide complexes can be found in the literature. The present work describes a theoretical study of the solvent effect on the prediction of the absorption spectra for lanthanide complexes, but other possible relevant factors have been also considered such as the molecular geometry and the excitation window used for interaction configuration (CI) calculations. The [Eu(ETA) 2· nH 2O] +1 complex has been chosen as an ideal candidate for this type of study due to its small number of atoms (only 49) and also because the absorption spectrum exhibits a single band. Two Monte Carlo simulations were performed, the first one considering the [Eu(ETA) 2] +1 complex in 400 water molecules, evidencing that the complex presents four coordinated water molecules. The second simulation considered the [Eu(ETA) 2·4H 2O] +1 complex in 400 ethanol molecules, in order to evaluate the solvent effect on the shift of the maximum absorption in calculated spectra, compared to the experimental one. Quantum chemical studies were also performed in order to evaluate the effect of the accuracy of calculated ground state geometry on the prediction of absorption spectra. The influence of the excitation window used for CI calculations on the spectral shift was also evaluated. No significant solvent effect was found on the prediction of the absorption spectrum for [Eu(ETA) 2·4H 2O] +1 complex. A small but significant effect of the ground state geometry on the transition energy and oscillator strength was also observed. Finally it must be emphasized that the absorption spectra of lanthanide complexes can be predicted with great accuracy by the combined use of semiempirical Sparkle/AM1 and INDO/S-CIS as long as the largest possible excitation window is used in the configuration interaction calculation.

  18. Understanding diagnosis and management of dementia and guideline implementation in general practice: a qualitative study using the theoretical domains framework

    PubMed Central

    2014-01-01

    Background Dementia is a growing problem, causing substantial burden for patients, their families, and society. General practitioners (GPs) play an important role in diagnosing and managing dementia; however, there are gaps between recommended and current practice. The aim of this study was to explore GPs’ reported practice in diagnosing and managing dementia and to describe, in theoretical terms, the proposed explanations for practice that was and was not consistent with evidence-based guidelines. Methods Semi-structured interviews were conducted with GPs in Victoria, Australia. The Theoretical Domains Framework (TDF) guided data collection and analysis. Interviews explored the factors hindering and enabling achievement of 13 recommended behaviours. Data were analysed using content and thematic analysis. This paper presents an in-depth description of the factors influencing two behaviours, assessing co-morbid depression using a validated tool, and conducting a formal cognitive assessment using a validated scale. Results A total of 30 GPs were interviewed. Most GPs reported that they did not assess for co-morbid depression using a validated tool as per recommended guidance. Barriers included the belief that depression can be adequately assessed using general clinical indicators and that validated tools provide little additional information (theoretical domain of ‘Beliefs about consequences’); discomfort in using validated tools (‘Emotion’), possibly due to limited training and confidence (‘Skills’; ‘Beliefs about capabilities’); limited awareness of the need for, and forgetting to conduct, a depression assessment (‘Knowledge’; ‘Memory, attention and decision processes’). Most reported practising in a manner consistent with the recommendation that a formal cognitive assessment using a validated scale be undertaken. Key factors enabling this were having an awareness of the need to conduct a cognitive assessment (‘Knowledge’); possessing the necessary skills and confidence (‘Skills’; ‘Beliefs about capabilities’); and having adequate time and resources (‘Environmental context and resources’). Conclusions This is the first study to our knowledge to use a theoretical approach to investigate the barriers and enablers to guideline-recommended diagnosis and management of dementia in general practice. It has identified key factors likely to explain GPs’ uptake of the guidelines. The results have informed the design of an intervention aimed at supporting practice change in line with dementia guidelines, which is currently being evaluated in a cluster randomised trial. PMID:24581339

  19. The Analysis on Influence of Main Factors on Theoretical Value of Energy Saving Rate for Energy Efficiency Labeling of Civil Buildings

    NASA Astrophysics Data System (ADS)

    Wang, Zhiwei; Wang, Zhenling; Jiang, Bo; Zhang, Fan; Li, Peng; Cao, Wei

    For typical residential buildings, no-large-scale and large-scale public buildings, according to China's Technical Guide for the Energy Efficiency Labeling of Civil Buildings, makes up missing data of the calculation benchmark and determines the boundary conditions for calculating the theoretical values of civil building energy efficiency. Based on equivalent full load hours method, develops a modular program and calculates building energy consumption for the demands of dynamic cooling and heating and lighting etc., finds out the corresponding relationship between star level's theoretical value of energy saving rate and specified-term limiting value in the Guide. With orthogonal experimental design and multiple linear regression, establishes the quantitative function of both the theoretical value of energy saving rate and main factors parameters, analyzes the impact of the control parameter on energy saving rate, and reveals the law of theoretical value of energy saving rate variation with the control parameter. For building energy efficiency labeling upgrade, presents technical measure need to be taken and analyses its feasibility. The results from the study can provide theoretical guidance for energy-saving design or retrofitting of civil buildings.

  20. A theoretical framework for the net land-to-atmosphere CO2 flux and its implications in the definition of "emissions from land-use change"

    NASA Astrophysics Data System (ADS)

    Gasser, T.; Ciais, P.

    2013-06-01

    We develop a theoretical framework and analysis of the net land-to-atmosphere CO2 flux in order to discuss possible definitions of "emissions from land-use change". The terrestrial biosphere is affected by two perturbations: the perturbation of the global carbon-climate-nitrogen system (CCN) with elevated atmospheric CO2, climate change and nitrogen deposition; and the land-use change perturbation (LUC). Here, we progressively establish mathematical definitions of four generic components of the net land-to-atmosphere CO2 flux. The two first components are the fluxes that would be observed if only one perturbation occurred. The two other components are due to the coupling of the CCN and LUC perturbations, which shows the non-linear response of the terrestrial carbon cycle. Thanks to these four components, we introduce three possible definitions of "emissions from land-use change" that are indeed used in the scientific literature, often without clear distinctions, and we draw conclusions as for their absolute and relative behaviors. Thanks to the OSCAR v2 model, we provide quantitative estimates of the differences between the three definitions, and we find that comparing results from studies that do not use the same definition can lead to a bias of up to 20% between estimates of those emissions. After discussion of the limitations of the framework, we conclude on the three major points of this study that should help the community to reconcile modeling and observation of emissions from land-use change. The appendix mainly provides more detailed mathematical expressions of the four components of the net land-to-atmosphere CO2 flux.

  1. A theoretical framework for the net land-to-atmosphere CO2 flux and its implications in the definition of "emissions from land-use change"

    NASA Astrophysics Data System (ADS)

    Gasser, T.; Ciais, P.

    2013-01-01

    We develop a theoretical framework and analysis of the net land-to-atmosphere CO2 flux in order to discuss possible definitions of "emissions from land-use change". The terrestrial biosphere is affected by two perturbations: the perturbation of the global Carbon-Climate-Nitrogen system (CCN) with elevated atmospheric CO2, climate change and nitrogen deposition; and the Land-Use Change perturbation (LUC). Here, we progressively establish mathematical definitions of four generic components of the net land-to-atmosphere CO2 flux. The two first components are the fluxes that would be observed if only one perturbation occurred. The two other components are due to the coupling of the CCN and LUC perturbations, which shows the non-linear response of the terrestrial carbon cycle. Thanks to these four components, we introduce three possible definitions of "emissions from land-use change", that are indeed used in the scientific literature, often without clear distinctions, and we draw conclusions as for their absolute and relative behaviors. Thanks to the OSCAR v2 model, we provide quantitative estimates of the differences between the three definitions, and we find that comparing results from studies that do not use the same definition can lead to a bias of up to 20% between estimates of those emissions. After discussion of the limitations of the framework, we conclude on the three major points of this study that should help the community to reconcile modeling and observation of emissions from land-use change. The Appendix mainly provides more detailed mathematical expressions of the four components of the net land-to-atmosphere CO2 flux.

  2. Biomechanics of the Sensor–Tissue Interface—Effects of Motion, Pressure, and Design on Sensor Performance and the Foreign Body Response—Part I: Theoretical Framework

    PubMed Central

    Helton, Kristen L; Ratner, Buddy D; Wisniewski, Natalie A

    2011-01-01

    The importance of biomechanics in glucose sensor function has been largely overlooked. This article is the first part of a two-part review in which we look beyond commonly recognized chemical biocompatibility to explore the biomechanics of the sensor–tissue interface as an important aspect of continuous glucose sensor biocompatibility. Part I provides a theoretical framework to describe how biomechanical factors such as motion and pressure (typically micromotion and micropressure) give rise to interfacial stresses, which affect tissue physiology around a sensor and, in turn, impact sensor performance. Three main contributors to sensor motion and pressure are explored: applied forces, sensor design, and subject/patient considerations. We describe how acute forces can temporarily impact sensor signal and how chronic forces can alter the foreign body response and inflammation around an implanted sensor, and thus impact sensor performance. The importance of sensor design (e.g., size, shape, modulus, texture) and specific implant location on the tissue response are also explored. In Part II: Examples and Application (a sister publication), examples from the literature are reviewed, and the application of biomechanical concepts to sensor design are described. We believe that adding biomechanical strategies to the arsenal of material compositions, surface modifications, drug elution, and other chemical strategies will lead to improvements in sensor biocompatibility and performance. PMID:21722578

  3. Population mixing and the adaptive divergence of quantitative traits in discrete populations: a theoretical framework for empirical tests.

    PubMed

    Hendry, A P; Day, T; Taylor, E B

    2001-03-01

    Empirical tests for the importance of population mixing in constraining adaptive divergence have not been well grounded in theory for quantitative traits in spatially discrete populations. We develop quantitative-genetic models to examine the equilibrium difference between two populations that are experiencing different selective regimes and exchanging individuals. These models demonstrate that adaptive divergence is negatively correlated with the rate of population mixing (m, most strongly so when m is low), positively correlated with the difference in phenotypic optima between populations, and positively correlated with the amount of additive genetic variance (G, most strongly so when G is low). The approach to equilibrium is quite rapid (fewer than 50 generations for two populations to evolve 90% of the distance to equilibrium) when either heritability or mixing are not too low (h2 > 0.2 or m > 0.05). The theory can be used to aid empirical tests that: (1) compare observed divergence to that predicted using estimates of population mixing, additive genetic variance/covariance, and selection; (2) test for a negative correlation between population mixing and adaptive divergence across multiple independent population pairs; and (3) experimentally manipulate the rate of mixing. Application of the first two of these approaches to data from two well-studied natural systems suggests that population mixing has constrained adaptive divergence for color patterns in Lake Erie water snakes (Nerodia sipedon), but not for trophic traits in sympatric pairs of benthic and limnetic stickleback (Gasterosteus aculeatus). The theoretical framework we outline should provide an improved basis for future empirical tests of the role of population mixing in adaptive divergence. PMID:11327154

  4. Towards a Theoretical Framework for the Comparative Understanding of Globalisation, Higher Education, the Labour Market and Inequality

    ERIC Educational Resources Information Center

    Kupfer, Antonia

    2011-01-01

    This paper is a theoretical examination of three major empirical trends that affect many people: globalisation, increasingly close relations between higher education (HE) and labour markets, and increasing social inequality. Its aim is to identify key theoretical resources and their contribution to the development of a comparative theoretical…

  5. River restoration in Spain: theoretical and practical approach in the context of the European water framework directive.

    PubMed

    González Del Tánago, Marta; García de Jalón, Diego; Román, Mercedes

    2012-07-01

    River restoration is becoming a priority in many countries because of increasing the awareness of environmental degradation. In Europe, the EU Water Framework Directive (WFD) has significantly reinforced river restoration, encouraging the improvement of ecological status for water bodies. To fulfill the WFD requirements, the Spanish Ministry of the Environment developed in 2006 a National Strategy for River Restoration whose design and implementation are described in this paper. At the same time many restoration projects have been conducted, and sixty of them have been evaluated in terms of stated objectives and pressures and implemented restoration measures. Riparian vegetation enhancement, weir removal and fish passes were the most frequently implemented restoration measures, although the greatest pressures came from hydrologic alteration caused by flow regulation for irrigation purposes. Water deficits in quantity and quality associated with uncontrolled water demands seriously affect Mediterranean rivers and represent the main constraint to achieving good ecological status of Spanish rivers, most of them intensively regulated. Proper environmental allocation of in-stream flows would need deep restrictions in agricultural water use which seem to be of very difficult social acceptance. This situation highlights the need to integrate land-use and rural development policies with water resources and river management, and identifies additional difficulties in achieving the WFD objectives and good ecological status of rivers in Mediterranean countries. PMID:22569704

  6. A direct vulnerable atherosclerotic plaque elasticity reconstruction method based on an original material-finite element formulation: theoretical framework

    PubMed Central

    Bouvier, Adeline; Deleaval, Flavien; Doyley, Marvin M; Yazdani, Saami K; Finet, Gérard; Le Floc'h, Simon; Cloutier, Guy; Pettigrew, Roderic I; Ohayon, Jacques

    2016-01-01

    The peak cap stress (PCS) amplitude is recognized as a biomechanical predictor of vulnerable plaque (VP) rupture. However, quantifying PCS in vivo remains a challenge since the stress depends on the plaque mechanical properties. In response, an iterative material finite element (FE) elasticity reconstruction method using strain measurements has been implemented for the solution of these inverse problems. Although this approach could resolve the mechanical characterization of VPs, it suffers from major limitations since (i) it is not adapted to characterize VPs exhibiting high material discontinuities between inclusions, and (ii) does not permit real time elasticity reconstruction for clinical use. The present theoretical study was therefore designed to develop a direct material-FE algorithm for elasticity reconstruction problems which accounts for material heterogeneities. We originally modified and adapted the extended FE method (Xfem), used mainly in crack analysis, to model material heterogeneities. This new algorithm was successfully applied to six coronary lesions of patients imaged in vivo with intravascular ultrasound. The results demonstrated that the mean relative absolute errors of the reconstructed Young's moduli obtained for the arterial wall, fibrosis, necrotic core, and calcified regions of the VPs decreased from 95.3±15.56%, 98.85±72.42%, 103.29±111.86% and 95.3±10.49%, respectively, to values smaller than 2.6 × 10?8±5.7 × 10?8% (i.e. close to the exact solutions) when including modified-Xfem method into our direct elasticity reconstruction method. PMID:24240392

  7. Vulnerable Atherosclerotic Plaque Elasticity Reconstruction Based on a Segmentation-Driven Optimization Procedure Using Strain Measurements: Theoretical Framework

    PubMed Central

    Le Floc’h, Simon; Tracqui, Philippe; Finet, Gérard; Gharib, Ahmed M.; Maurice, Roch L.; Cloutier, Guy; Pettigrew, Roderic I.

    2016-01-01

    It is now recognized that prediction of the vulnerable coronary plaque rupture requires not only an accurate quantification of fibrous cap thickness and necrotic core morphology but also a precise knowledge of the mechanical properties of plaque components. Indeed, such knowledge would allow a precise evaluation of the peak cap-stress amplitude, which is known to be a good biomechanical predictor of plaque rupture. Several studies have been performed to reconstruct a Young’s modulus map from strain elastograms. It seems that the main issue for improving such methods does not rely on the optimization algorithm itself, but rather on preconditioning requiring the best estimation of the plaque components’ contours. The present theoretical study was therefore designed to develop: 1) a preconditioning model to extract the plaque morphology in order to initiate the optimization process, and 2) an approach combining a dynamic segmentation method with an optimization procedure to highlight the modulogram of the atherosclerotic plaque. This methodology, based on the continuum mechanics theory prescribing the strain field, was successfully applied to seven intravascular ultrasound coronary lesion morphologies. The reconstructed cap thickness, necrotic core area, calcium area, and the Young’s moduli of the calcium, necrotic core, and fibrosis were obtained with mean relative errors of 12%, 4% and 1%, 43%, 32%, and 2%, respectively. PMID:19164080

  8. A direct vulnerable atherosclerotic plaque elasticity reconstruction method based on an original material-finite element formulation: theoretical framework

    NASA Astrophysics Data System (ADS)

    Bouvier, Adeline; Deleaval, Flavien; Doyley, Marvin M.; Yazdani, Saami K.; Finet, Gérard; Le Floc'h, Simon; Cloutier, Guy; Pettigrew, Roderic I.; Ohayon, Jacques

    2013-12-01

    The peak cap stress (PCS) amplitude is recognized as a biomechanical predictor of vulnerable plaque (VP) rupture. However, quantifying PCS in vivo remains a challenge since the stress depends on the plaque mechanical properties. In response, an iterative material finite element (FE) elasticity reconstruction method using strain measurements has been implemented for the solution of these inverse problems. Although this approach could resolve the mechanical characterization of VPs, it suffers from major limitations since (i) it is not adapted to characterize VPs exhibiting high material discontinuities between inclusions, and (ii) does not permit real time elasticity reconstruction for clinical use. The present theoretical study was therefore designed to develop a direct material-FE algorithm for elasticity reconstruction problems which accounts for material heterogeneities. We originally modified and adapted the extended FE method (Xfem), used mainly in crack analysis, to model material heterogeneities. This new algorithm was successfully applied to six coronary lesions of patients imaged in vivo with intravascular ultrasound. The results demonstrated that the mean relative absolute errors of the reconstructed Young's moduli obtained for the arterial wall, fibrosis, necrotic core, and calcified regions of the VPs decreased from 95.3±15.56%, 98.85±72.42%, 103.29±111.86% and 95.3±10.49%, respectively, to values smaller than 2.6 × 10-8±5.7 × 10-8% (i.e. close to the exact solutions) when including modified-Xfem method into our direct elasticity reconstruction method.

  9. Assessing Students' Understandings of Biological Models and Their Use in Science to Evaluate a Theoretical Framework

    ERIC Educational Resources Information Center

    Grünkorn, Juliane; Upmeier zu Belzen, Annette; Krüger, Dirk

    2014-01-01

    Research in the field of students' understandings of models and their use in science describes different frameworks concerning these understandings. Currently, there is no conjoint framework that combines these structures and so far, no investigation has focused on whether it reflects students' understandings sufficiently (empirical…

  10. Assessing Students' Understandings of Biological Models and Their Use in Science to Evaluate a Theoretical Framework

    ERIC Educational Resources Information Center

    Grünkorn, Juliane; Upmeier zu Belzen, Annette; Krüger, Dirk

    2014-01-01

    Research in the field of students' understandings of models and their use in science describes different frameworks concerning these understandings. Currently, there is no conjoint framework that combines these structures and so far, no investigation has focused on whether it reflects students' understandings sufficiently (empirical…

  11. A HIGHLY CONSISTENT FRAMEWORK FOR THE EVOLUTION OF THE STAR-FORMING ''MAIN SEQUENCE'' FROM z ∼ 0-6

    SciTech Connect

    Speagle, J. S.; Steinhardt, C. L.; Silverman, J. D.; Capak, P. L.

    2014-10-01

    Using a compilation of 25 studies from the literature, we investigate the evolution of the star-forming galaxy (SFG) main sequence (MS) in stellar mass and star formation rate (SFR) out to z ∼ 6. After converting all observations to a common set of calibrations, we find a remarkable consensus among MS observations (∼0.1 dex 1σ interpublication scatter). By fitting for time evolution of the MS in bins of constant mass, we deconvolve the observed scatter about the MS within each observed redshift bin. After accounting for observed scatter between different SFR indicators, we find the width of the MS distribution is ∼0.2 dex and remains constant over cosmic time. Our best fits indicate the slope of the MS is likely time-dependent, with our best-fit log SFR(M {sub *}, t) = (0.84 ± 0.02 – 0.026 ± 0.003 × t)log M {sub *} – (6.51 ± 0.24 – 0.11 ± 0.03 × t), where t is the age of the universe in Gyr. We use our fits to create empirical evolutionary tracks in order to constrain MS galaxy star formation histories (SFHs), finding that (1) the most accurate representations of MS SFHs are given by delayed-τ models, (2) the decline in fractional stellar mass growth for a ''typical'' MS galaxy today is approximately linear for most of its lifetime, and (3) scatter about the MS can be generated by galaxies evolving along identical evolutionary tracks assuming an initial 1σ spread in formation times of ∼1.4 Gyr.

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

    PubMed

    Jommi, Claudio; Paruzzolo, Silvia

    2007-04-01

    This article has two objectives. It firstly provides a general framework for variables that influence R&D (Research and Development) localisation by pharmaceutical and biotech companies. The analysis of R&D localization includes both in-house R&D and contracted R&D. Following a systematic literature search, these variables were classified into four distinct categories: regulatory environment, institutional framework, national systems of innovation and local development and specialisation. The authors highlight that some of these factors directly depend on the action of public administrations (e.g., patent protection, price regulation, public investments in research, and incentives to private companies); others are indirectly influenced by public policies (e.g., GDP growth rate, infrastructures). This theoretical framework was used to analyse the Italian case-study. Pros and cons of the Italian context were investigated from the point of view of multinational pharmaceutical companies and the Italian Association of Biotech Companies. Interviews were chosen as the most appropriate data gathering technique given the exploratory nature of the study of the Italian context. The paper is divided into five parts. A brief introduction provides figures showing that Europe has been loosing positions compared with other Continents and the same has occurred in Italy compared with other EU countries. The second one illustrates the methodology. The third one is focused on variables affecting R&D localisation. In the fourth section the Italian case-study is discussed. Theoretical and empirical findings are summarised and discussed in the conclusions. PMID:16824641

  13. Organizational Culture and Organizational Effectiveness: A Meta-Analytic Investigation of the Competing Values Framework's Theoretical Suppositions

    ERIC Educational Resources Information Center

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

    2011-01-01

    We apply Quinn and Rohrbaugh's (1983) competing values framework (CVF) as an organizing taxonomy to meta-analytically test hypotheses about the relationship between 3 culture types and 3 major indices of organizational effectiveness (employee attitudes, operational performance [i.e., innovation and product and service quality], and financial…

  14. The Role of Body Image in the Relationship Between Internet Use and Bulimic Symptoms: Three Theoretical Frameworks.

    PubMed

    Melioli, Tiffany; Rodgers, Rachel F; Rodrigues, Marie; Chabrol, Henri

    2015-11-01

    Exposure to traditional media has been associated with bulimic symptoms. However, to date, little is known regarding the effects of Internet exposure. The aim of this study was to explore the relationships between Internet use and bulimic symptoms within the competing frameworks of sociocultural, impression management, and self-objectification theory. A sample of 289 French women aged 18-25 years completed an online questionnaire assessing bulimic symptoms, body dissatisfaction, body image avoidance, self-surveillance, body shame, and weekly Internet use. Bootstrapping analyses revealed that body shame and body image avoidance mediated the effect of weekly Internet use on bulimic symptoms. Furthermore, when entered into a multiple mediation analysis, these two variables provided independent mediation pathways of equal magnitude. The findings support the usefulness of both the self-objectification and impression management frameworks for investigating the relationship between Internet use and bulimic symptoms. Longitudinal research would help to clarify these pathways further. PMID:26378881

  15. Selective gas adsorption in microporous metal-organic frameworks incorporating urotropine basic sites: an experimental and theoretical study.

    PubMed

    Sapchenko, S A; Dybtsev, D N; Samsonenko, D G; Belosludov, R V; Belosludov, V R; Kawazoe, Y; Schröder, M; Fedin, V P

    2015-09-21

    The sorption of CO, CO2 and C2H2 by two urotropine-containing porous metal-organic framework materials [Zn4(dmf)(ur)2(ndc)4] (H2ndc = 2,6-naphthalenedicarboxylic acid; ur = urotropine; dmf = dimethylformamide) and [Zn11(H2O)2(ur)4(bpdc)11] (H4bpdc = 4,4'-biphenyldicarboxylic acid) incorporating free N-donors has been investigated. These materials show pronounced affinity for CO2 and C2H2, and these observations are supported by interaction energy and ab initio DFT calculations. PMID:26238221

  16. HIV-Associated Orphanhood and Children’s Psychosocial Distress: Theoretical Framework Tested With Data From Zimbabwe

    PubMed Central

    Nyamukapa, Constance A.; Gregson, Simon; Lopman, Ben; Saito, Suzue; Watts, Helen J.; Monasch, Roeland; Jukes, Matthew C.H.

    2008-01-01

    Objectives. We measured the psychosocial effect of orphanhood in a sub-Saharan African population and evaluated a new framework for understanding the causes and consequences of psychosocial distress among orphans and other vulnerable children. Methods. The framework was evaluated using data from 5321 children aged 12 to 17 years who were interviewed in a 2004 national survey in Zimbabwe. We constructed a measure of psychosocial distress using principle components analysis. We used regression analyses to obtain standardized parameter estimates of psychosocial distress and odds ratios of early sexual activity. Results. Orphans had more psychosocial distress than did nonorphans. For both genders, paternal, maternal, and double orphans exhibited more-severe distress than did nonorphaned, nonvulnerable children. Orphanhood remained associated with psychosocial distress after we controlled for differences in more-proximate determinants. Maternal and paternal orphans were significantly more likely than were nonorphaned, nonvulnerable children to have engaged in sexual activity. These differences were reduced after we controlled for psychosocial distress. Conclusions. Orphaned adolescents in Zimbabwe suffer greater psychosocial distress than do nonorphaned, nonvulnerable children, which may lead to increased likelihood of early onset of sexual intercourse and HIV infection. The effect of strategies to provide psychosocial support should be evaluated scientifically. PMID:18048777

  17. 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. PMID:24016206

  18. The effect of fire-induced soil hydrophobicity on wind erosion in a semiarid grassland: Experimental observations and theoretical framework

    NASA Astrophysics Data System (ADS)

    Ravi, Sujith; D'Odorico, Paolo; Zobeck, Ted M.; Over, Thomas M.

    2009-04-01

    Aridland ecosystems are often susceptible to degradation resulting from disturbances like fires and grazing. By exposing the soil surface to the erosive action of winds, these disturbances contribute to the redistribution of soil nutrients associated with grassland-to-shrubland conversions and to the formation of a heterogeneous landscape. Wind erosion maintains the local heterogeneities in nutrient and vegetation distribution in arid landscapes through the removal of nutrient-rich soil from the intercanopy areas and the subsequent deposition of soil onto vegetation patches. Even though wind erosion and disturbances like fires strongly interact with each other and determine vegetation patterns in arid landscapes, very few studies have addressed these interactions. Using soil samples collected after a wildfire event at the Cimarron National Grasslands in southwestern Kansas, we demonstrate through a series of wind-tunnel experiments, laboratory measurements, and theoretical analyses how wind erosion can be enhanced by fire-induced water repellency. Results from the wind-tunnel experiments show that in semiarid grasslands fires can cause a decrease in the threshold velocity of wind erosion thereby, enhancing the post-burn erosion of (hydrophobic) soils. Further, a generalized process-based theoretical equation was derived to explain the decrease in threshold friction velocity in water-repellent soil for the case of soil particles modeled as asymmetrical cones.

  19. Tetrazine chromophore-based metal-organic frameworks with unusual configurations: synthetic, structural, theoretical, fluorescent, and nonlinear optical studies.

    PubMed

    Li, Jianghua; Jia, Ding; Meng, Suci; Zhang, Jinfang; Cifuentes, Marie P; Humphrey, Mark G; Zhang, Chi

    2015-05-18

    Three unusual three-dimensional (3D) tetrazine chromophore-based metal-organic frameworks (MOFs) {(Et4 N)[WS4 Cu3 (CN)2 (4,4'-pytz)0.5 ]}n (1), {[MoS4 Cu4 (CN)2 (4,4'-pytz)2 ]⋅CH2 Cl2 }n (2), and {[WS4 Cu3 (4,4'-pytz)3 ]⋅[N(CN)2 ]}n (3; 4,4'-pytz=3,6-bis(4-pyridyl)tetrazine) have been synthesized and characterized by using FTIR and UV/Vis spectroscopy, elemental analysis, powder X-ray diffraction, gel permeation chromatography, steady-state fluorescence, and thermogravimetric analysis; their identities were confirmed by single-crystal X-ray diffraction studies. MOF 1 possesses the first five-connected M/S/Cu (M=Mo, W) framework with an unusual 3D (4(4) ⋅6(6) ) topology constructed from T-shaped [WS4 Cu3 ](+) clusters as nodes and single CN(-) /4,4'-pytz bridges as linkers. MOF 2 features a novel 3D MOF structure with (4(20) ⋅6(8) ) topology, in which the bridging 4,4'-pytz ligands exhibit unique distorted arch structures. MOF 3 displays the first 3D MOF structure based on flywheel-shaped [WS4 Cu3 ](+) clusters with a non-interpenetrating honeycomb-like framework and a heavily distorted "ACS" topology. Steady-state fluorescence studies of 1-3 reveal significant fluorescence emissions. The nonlinear optical (NLO) properties of 1-3 were investigated by using a Z-scan technique with 5 ns pulses at λ=532 nm. The Z-scan experimental results show that the π-delocalizable tetrazine-based 4,4'-pytz ligands contribute to the strong third-order NLO properties exhibited by 1-3. Time-dependent density functional theory studies afforded insight into the electronic transitions and spectral characterization of these functionalized NLO molecular materials. PMID:25877804

  20. Experimental and theoretical investigations of the electronic band structure of metal-organic frameworks of HKUST-1 type

    NASA Astrophysics Data System (ADS)

    Gu, Zhi-Gang; Heinke, Lars; Wöll, Christof; Neumann, Tobias; Wenzel, Wolfgang; Li, Qiang; Fink, Karin; Gordan, Ovidiu D.; Zahn, Dietrich R. T.

    2015-11-01

    The electronic properties of metal-organic frameworks (MOFs) are increasingly attracting the attention due to potential applications in sensor techniques and (micro-) electronic engineering, for instance, as low-k-dielectric in semiconductor technology. Here, the band gap and the band structure of MOFs of type HKUST-1 are studied in detail by means of spectroscopic ellipsometry applied to thin surface-mounted MOF films and by means of quantum chemical calculations. The analysis of the density of states, the band structure, and the excitation spectrum reveal the importance of the empty Cu-3d orbitals for the electronic properties of HKUST-1. This study shows that, in contrast to common belief, even in the case of this fairly "simple" MOF, the excitation spectra cannot be explained by a superposition of "intra-unit" excitations within the individual building blocks. Instead, "inter-unit" excitations also have to be considered.

  1. The Introduction of Two-Tiered Study Structures in the Context of the Bologna Process: A Theoretical Framework for an International Comparative Study of Change in Higher Education Systems

    ERIC Educational Resources Information Center

    Witte, Johanna

    2004-01-01

    This article presents a theoretical framework for an encompassing international comparative study of a central aspect of the Bologna process; the introduction of two-tiered study structures (TTSS), often referred to as "Bachelor and Master". The framework is tailored to understand and explain the patterns of TTSS that currently emerge in various…

  2. Signalling entropy: A novel network-theoretical framework for systems analysis and interpretation of functional omic data.

    PubMed

    Teschendorff, Andrew E; Sollich, Peter; Kuehn, Reimer

    2014-06-01

    A key challenge in systems biology is the elucidation of the underlying principles, or fundamental laws, which determine the cellular phenotype. Understanding how these fundamental principles are altered in diseases like cancer is important for translating basic scientific knowledge into clinical advances. While significant progress is being made, with the identification of novel drug targets and treatments by means of systems biological methods, our fundamental systems level understanding of why certain treatments succeed and others fail is still lacking. We here advocate a novel methodological framework for systems analysis and interpretation of molecular omic data, which is based on statistical mechanical principles. Specifically, we propose the notion of cellular signalling entropy (or uncertainty), as a novel means of analysing and interpreting omic data, and more fundamentally, as a means of elucidating systems-level principles underlying basic biology and disease. We describe the power of signalling entropy to discriminate cells according to differentiation potential and cancer status. We further argue the case for an empirical cellular entropy-robustness correlation theorem and demonstrate its existence in cancer cell line drug sensitivity data. Specifically, we find that high signalling entropy correlates with drug resistance and further describe how entropy could be used to identify the achilles heels of cancer cells. In summary, signalling entropy is a deep and powerful concept, based on rigorous statistical mechanical principles, which, with improved data quality and coverage, will allow a much deeper understanding of the systems biological principles underlying normal and disease physiology. PMID:24675401

  3. Theoretical estimation of fusion-fission cross section for superheavy elements in the framework of fluctuation-dissipation model

    NASA Astrophysics Data System (ADS)

    Aritomo, Yoshihiro

    2001-10-01

    At Dubna, the experiments of synthesizing Z=3D114 and Z=3D116 nuclei were done by hot fusion reaction. In fusion reaction in heavy systems, it is well known that there exists a hindrance which is explained as extra- or extra-extra-push energy due to the strong dissipation for collective motion of nuclear matter. To explain the fusion hindrance, the trajectory calculations with friction was very useful. When the fusion hindrance is very large, it is necessary to solve a full dissipative dynamics. By using the Langevin equation, we calculated the evaporation residue cross section of superheavy elements for the reactions ^48Ca+^208Pb, ^48Ca+^238U, ^48Ca+^244Pu and ^48Ca+^248Cm. We divide the whole dynamical process into three stages; the first stage is the process of the potential barrier penetration, then the second stage is the process from the point corresponding to the touching of two colliding nuclei to the formation of compound nucleus under the competition between complete fusion and quasi-fission. The third stage is decay process of compound nuclei under the competition between fission and neutron evaporation. The first stage is used simple WKB method, and second stage is treated the three-dimensional Langevin equation. Then in the third stage, we calculate the survival probability using the theoretical formula based on ?_n/?_f. I will discuss the evaporation residue cross section and survival probability.

  4. A theoretical framework to model DSC-MRI data acquired in the presence of contrast agent extravasation

    NASA Astrophysics Data System (ADS)

    Quarles, C. C.; Gochberg, D. F.; Gore, J. C.; Yankeelov, T. E.

    2009-10-01

    Dynamic susceptibility contrast (DSC) MRI methods rely on compartmentalization of the contrast agent such that a susceptibility gradient can be induced between the contrast-containing compartment and adjacent spaces, such as between intravascular and extravascular spaces. When there is a disruption of the blood-brain barrier, as is frequently the case with brain tumors, a contrast agent leaks out of the vasculature, resulting in additional T1, T2 and T*2 relaxation effects in the extravascular space, thereby affecting the signal intensity time course and reducing the reliability of the computed hemodynamic parameters. In this study, a theoretical model describing these dynamic intra- and extravascular T1, T2 and T*2 relaxation interactions is proposed. The applicability of using the proposed model to investigate the influence of relevant MRI pulse sequences (e.g. echo time, flip angle), and physical (e.g. susceptibility calibration factors, pre-contrast relaxation rates) and physiological parameters (e.g. permeability, blood flow, compartmental volume fractions) on DSC-MRI signal time curves is demonstrated. Such a model could yield important insights into the biophysical basis of contrast-agent-extravasastion-induced effects on measured DSC-MRI signals and provide a means to investigate pulse sequence optimization and appropriate data analysis methods for the extraction of physiologically relevant imaging metrics.

  5. [A history of primary health care policy in the Federal District, Brazil (1960-2007): an analysis based on the theoretical framework of historical neo-institutionalism].

    PubMed

    Göttems, Leila Bernardo Donato; Evangelista, Maria do Socorro Nantua; Pires, Maria Raquel Gomes Maia; Silva, Aline Ferreira Melgaço da; Silva, Priscila Avelino da

    2009-06-01

    This article analyzes the history of primary health care policy in the Federal District, Brazil, based on the theoretical framework of historical neo-institutionalism, identifying the predominant configurations and trends in the various administrations of the State Health Secretariat (SES-DF) from 1960 to 2007. The study indicates that the characteristics of the Federal District's health policy are dependent on the history of the original health system plans for setting priorities and goals, as well as for the health system's implementation. This influence, in addition to the centralization of decision-making processes and limited political participation, can contribute to making primary care ancillary to hospital care, thus jeopardizing its potential to produce change in the health care model. PMID:19503971

  6. Barriers and enablers to delivery of the Healthy Kids Check: an analysis informed by the Theoretical Domains Framework and COM-B model

    PubMed Central

    2014-01-01

    Background More than a fifth of Australian children arrive at school developmentally vulnerable. To counteract this, the Healthy Kids Check (HKC), a one-off health assessment aimed at preschool children, was introduced in 2008 into Australian general practice. Delivery of services has, however, remained low. The Theoretical Domains Framework, which provides a method to understand behaviours theoretically, can be condensed into three core components: capability, opportunity and motivation, and the COM-B model. Utilising this system, this study aimed to determine the barriers and enablers to delivery of the HKC, to inform the design of an intervention to promote provision of HKC services in Australian general practice. Methods Data from 6 focus group discussions with 40 practitioners from general practices in socio-culturally diverse areas of Melbourne, Victoria, were analysed using thematic analysis. Results Many practitioners expressed uncertainty regarding their capabilities and the practicalities of delivering HKCs, but in some cases HKCs had acted as a catalyst for professional development. Key connections between immunisation services and delivery of HKCs prompted practices to have systems of recall and reminder in place. Standardisation of methods for developmental assessment and streamlined referral pathways affected practitioners’ confidence and motivation to perform HKCs. Conclusion Application of a systematic framework effectively demonstrated how a number of behaviours could be targeted to increase delivery of HKCs. Interventions need to target practice systems, the support of office staff and referral options, as well as practitioners’ training. Many behavioural changes could be applied through a single intervention programme delivered by the primary healthcare organisations charged with local healthcare needs (Medicare Locals) providing vital links between general practice, community and the health of young children. PMID:24886520

  7. Back to the basics: identifying positive youth development as the theoretical framework for a youth drug prevention program in rural Saskatchewan, Canada amidst a program evaluation

    PubMed Central

    2013-01-01

    Background Despite endorsement by the Saskatchewan government to apply empirically-based approaches to youth drug prevention services in the province, programs are sometimes delivered prior to the establishment of evidence-informed goals and objectives. This paper shares the 'preptory’ outcomes of our team’s program evaluation of the Prince Albert Parkland Health Region Mental Health and Addiction Services’ Outreach Worker Service (OWS) in eight rural, community schools three years following its implementation. Before our independent evaluation team could assess whether expectations of the OWS were being met, we had to assist with establishing its overarching program goals and objectives and 'at-risk’ student population, alongside its alliance with an empirically-informed theoretical framework. Methods A mixed-methods approach was applied, beginning with in-depth focus groups with the OWS staff to identify the program’s goals and objectives and targeted student population. These were supplemented with OWS and school administrator interviews and focus groups with school staff. Alignment with a theoretical focus was determined though a review of the OWS’s work to date and explored in focus groups between our evaluation team and the OWS staff and validated with the school staff and OWS and school administration. Results With improved understanding of the OWS’s goals and objectives, our evaluation team and the OWS staff aligned the program with the Positive Youth Development theoretical evidence-base, emphasizing the program’s universality, systems focus, strength base, and promotion of assets. Together we also gained clarity about the OWS’s definition of and engagement with its 'at-risk’ student population. Conclusions It is important to draw on expert knowledge to develop youth drug prevention programming, but attention must also be paid to aligning professional health care services with a theoretically informed evidence-base for evaluation purposes. If time does not permit for the establishment of evidence-informed goals and objectives at the start-up of a program, obtaining insight and expertise from program personnel and school staff and administrators can bring the program to a point where this can still be achieved and theoretical linkages made after a program has been implemented. This is a necessary foundation for measuring an intervention’s success. PMID:24148918

  8. A theoretical framework for whole-plant carbon assimilation efficiency based on metabolic scaling theory: a test case using Picea seedlings.

    PubMed

    Wang, Zhiqiang; Ji, Mingfei; Deng, Jianming; Milne, Richard I; Ran, Jinzhi; Zhang, Qiang; Fan, Zhexuan; Zhang, Xiaowei; Li, Jiangtao; Huang, Heng; Cheng, Dongliang; Niklas, Karl J

    2015-06-01

    Simultaneous and accurate measurements of whole-plant instantaneous carbon-use efficiency (ICUE) and annual total carbon-use efficiency (TCUE) are difficult to make, especially for trees. One usually estimates ICUE based on the net photosynthetic rate or the assumed proportional relationship between growth efficiency and ICUE. However, thus far, protocols for easily estimating annual TCUE remain problematic. Here, we present a theoretical framework (based on the metabolic scaling theory) to predict whole-plant annual TCUE by directly measuring instantaneous net photosynthetic and respiratory rates. This framework makes four predictions, which were evaluated empirically using seedlings of nine Picea taxa: (i) the flux rates of CO(2) and energy will scale isometrically as a function of plant size, (ii) whole-plant net and gross photosynthetic rates and the net primary productivity will scale isometrically with respect to total leaf mass, (iii) these scaling relationships will be independent of ambient temperature and humidity fluctuations (as measured within an experimental chamber) regardless of the instantaneous net photosynthetic rate or dark respiratory rate, or overall growth rate and (iv) TCUE will scale isometrically with respect to instantaneous efficiency of carbon use (i.e., the latter can be used to predict the former) across diverse species. These predictions were experimentally verified. We also found that the ranking of the nine taxa based on net photosynthetic rates differed from ranking based on either ICUE or TCUE. In addition, the absolute values of ICUE and TCUE significantly differed among the nine taxa, with both ICUE and temperature-corrected ICUE being highest for Picea abies and lowest for Picea schrenkiana. Nevertheless, the data are consistent with the predictions of our general theoretical framework, which can be used to access annual carbon-use efficiency of different species at the level of an individual plant based on simple, direct measurements. Moreover, we believe that our approach provides a way to cope with the complexities of different ecosystems, provided that sufficient measurements are taken to calibrate our approach to that of the system being studied. PMID:25939866

  9. Assessing Learning in the Outdoors with the Field Trip in Natural Environments (FiNE) Framework

    ERIC Educational Resources Information Center

    Morag, Orly; Tal, Tali

    2012-01-01

    The development and application of a framework that captures main characteristics of learning in nature--the Field Trip in Natural Environments (FiNE) framework--is the main outcome of this study that followed up 22 daily field trips of 4-6th grade students to nature parks. The theoretical and practical framework, which was developed based on the…

  10. A cross-country comparison of intensive care physicians’ beliefs about their transfusion behaviour: A qualitative study using the theoretical domains framework

    PubMed Central

    2012-01-01

    Background Evidence of variations in red blood cell transfusion practices have been reported in a wide range of clinical settings. Parallel studies in Canada and the United Kingdom were designed to explore transfusion behaviour in intensive care physicians. The aim of this paper is three-fold: first, to explore beliefs that influence Canadian intensive care physicians’ transfusion behaviour; second, to systematically select relevant theories and models using the Theoretical Domains Framework (TDF) to inform a future predictive study; and third, to compare its results with the UK study. Methods Ten intensive care unit (ICU) physicians throughout Canada were interviewed. Physicians’ responses were coded into theoretical domains, and specific beliefs were generated for each response. Theoretical domains relevant to behaviour change were identified, and specific constructs from the relevant domains were used to select psychological theories. The results from Canada and the United Kingdom were compared. Results Seven theoretical domains populated by 31 specific beliefs were identified as relevant to the target behaviour. The domains Beliefs about capabilities (confident to not transfuse if patients’ clinical condition is stable), Beliefs about consequences (positive beliefs of reducing infection and saving resources and negative beliefs about risking patients’ clinical outcome and potentially more work), Social influences (transfusion decision is influenced by team members and patients’ relatives), and Behavioural regulation (wide range of approaches to encourage restrictive transfusion) that were identified in the UK study were also relevant in the Canadian context. Three additional domains, Knowledge (it requires more evidence to support restrictive transfusion), Social/professional role and identity (conflicting beliefs about not adhering to guidelines, referring to evidence, believing restrictive transfusion as professional standard, and believing that guideline is important for other professionals), and Motivation and goals (opposing beliefs about the importance of restrictive transfusion and compatibility with other goals), were also identified in this study. Similar to the UK study, the Theory of Planned Behaviour, Social Cognitive Theory, Operant Learning Theory, Action Planning, and Knowledge-Attitude-Behaviour model were identified as potentially relevant theories and models for further study. Personal project analysis was added to the Canadian study to explore the Motivation and goals domain in further detail. Conclusions A wide range of beliefs was identified by the Canadian ICU physicians as likely to influence their transfusion behaviour. We were able to demonstrate similar though not identical results in a cross-country comparison. Designing targeted behaviour-change interventions based on unique beliefs identified by physicians from two countries are more likely to encourage restrictive transfusion in ICU physicians in respective countries. This needs to be tested in future prospective clinical trials. PMID:22999460

  11. Cloud vertical structure and the impact of MODIS liquid water path retrieval assumptions: Developing a theoretical framework and evaluating retrievals using large-eddy simulations

    NASA Astrophysics Data System (ADS)

    Miller, D. J.; Zhang, Z.; Platnick, S. E.; Ackerman, A. S.

    2014-12-01

    The vertical structure of marine boundary layer (MBL) clouds plays an important role in satellite retrievals of cloud microphysical properties such as droplet size (re) , liquid water path (LWP), and droplet number concentration (CDNC). Passive optical retrievals of LWP such as those performed by MODIS rely on cloud vertical structure assumptions to relate cloud optical thickness (?) and re retrievals to a corresponding LWP. Typically these passive remote sensing techniques assume that clouds are vertically homogenous [Platnick et al., 2003]. However, it has been suggested that an adiabatic cloud model could potentially introduce more realistic assumptions for some MBL cloud regimes [Wood and Hartmann, 2005; Bennartz, 2007]. In reality, cloud vertical structure is often more complicated than either of these assumptions because structure can be altered by both precipitation and mixing processes. This work examines the impact of varied and realistic cloud vertical structures on retrievals requiring fixed homogeneous or adiabatic structure assumptions. To address this we use the DHARMA cloud large-eddy simulation (LES) model [Ackerman et al. 2004] and a MODIS-like satellite retrieval simulator [Zhang et al. 2012]. The LES and retrieval simulator allow for the direct comparison of retrievals to the in-situ microphysical structure of the LES cloud field. Physical properties from the LES cloud field such as the degree of adiabaticity and droplet growth lapse rate are examined and linked to the impact of retrieval biases. The retrieval comparison led to the development of a predictive theoretical framework for determining which of the LES pixels satisfied either homogeneous or adiabatic vertical structure assumptions. The theoretical model was also utilized to extend a single-layer adiabatic cloud model to an arbitrary two-layer model capable of characterizing the impact of entrainment features on cloud retrievals performed on the LES. Our results overwhelmingly demonstrate that the impact of realistic cloud vertical structure on retrievals is more complicated than either of the vertical structure assumptions currently being implemented by the remote sensing community.

  12. Theoretical framework for the dual-energy cone-beam CT noise-power spectrum, NEQ, and tasked-based detectability index

    NASA Astrophysics Data System (ADS)

    Gang, G. J.; Zbijewski, W.; Stayman, J. W.; Carrino, J. A.; Siewerdsen, J. H.

    2012-03-01

    The optimization of dual-energy computed tomography (DE-CT) is challenged by the lack of a theoretical foundation for image quality. This work reports a cascaded systems analysis model that was used to derive signal and noise propagation in DE-CBCT in prevalent Fourier metrics such as the noise-power spectrum (NPS) and noise-equivalent quanta (NEQ). The model was validated in comparison to measurements of the 3D NPS and NEQ in DE-CBCT images acquired using an experimental imaging bench. Task-based detectability index was derived using DE-NPS and NEQ as an objective function in optimizing DE imaging parameters such as the dose allocation factor (DA) and kVp pair. The resulting dose allocation optimization is in agreement with the practice of assigning more dose to the high-energy image (DA < 0.5), and the model provides a quantitative basis for examining the optimal dose allocation as a function of total dose, kVp pair, the presence of electronics noise, and the imaging task. An example optimization is shown for a breast tumor detection task. Using DE decomposition to cancel fibroglandular tissue (rendering a DE-CBCT image of breast tumor against an adipose tissue background) and assuming a total dose of 15mGy, the optimal kVp pair is identified at [45, 105]kVp with DA=0.46. The model is sufficiently general for applications beyond this example, demonstrating utility in the optimization in a broad range of imaging parameters. The model provides a new, valuable framework for understanding the theoretical limits of DE-CBCT imaging performance and maximizing image quality while minimizing radiation dose.

  13. Fundamental relationship between the noise properties of grating-based differential phase contrast CT and absorption CT: Theoretical framework using a cascaded system model and experimental validation

    PubMed Central

    Li, Ke; Bevins, Nicholas; Zambelli, Joseph; Chen, Guang-Hong

    2013-01-01

    Purpose: Using a grating interferometer, a conventional x-ray cone beam computed tomography (CT) data acquisition system can be used to simultaneously generate both conventional absorption CT (ACT) and differential phase contrast CT (DPC-CT) images from a single data acquisition. Since the two CT images were extracted from the same set of x-ray projections, it is expected that intrinsic relationships exist between the noise properties of the two contrast mechanisms. The purpose of this paper is to investigate these relationships. Methods: First, a theoretical framework was developed using a cascaded system model analysis to investigate the relationship between the noise power spectra (NPS) of DPC-CT and ACT. Based on the derived analytical expressions of the NPS, the relationship between the spatial-frequency-dependent noise equivalent quanta (NEQ) of DPC-CT and ACT was derived. From these fundamental relationships, the NPS and NEQ of the DPC-CT system can be derived from the corresponding ACT system or vice versa. To validate these theoretical relationships, a benchtop cone beam DPC-CT/ACT system was used to experimentally measure the modulation transfer function (MTF) and NPS of both DPC-CT and ACT. The measured three-dimensional (3D) MTF and NPS were then combined to generate the corresponding 3D NEQ. Results: Two fundamental relationships have been theoretically derived and experimentally validated for the NPS and NEQ of DPC-CT and ACT: (1) the 3D NPS of DPC-CT is quantitatively related to the corresponding 3D NPS of ACT by an inplane-only spatial-frequency-dependent factor 1/f?2, the ratio of window functions applied to DPC-CT and ACT, and a numerical factor Cg determined by the geometry and efficiency of the grating interferometer. Note that the frequency-dependent factor is independent of the frequency component fz perpendicular to the axial plane. (2) The 3D NEQ of DPC-CT is related to the corresponding 3D NEQ of ACT by an f?2 scaling factor and numerical factors that depend on both the attenuation and refraction properties of the image object, as well as Cg and the MTF of the grating interferometer. Conclusions: The performance of a DPC-CT system is intrinsically related to the corresponding ACT system. As long as the NPS and NEQ of an ACT system is known, the corresponding NPS and NEQ of the DPC-CT system can be readily estimated using additional characteristics of the grating interferometer. PMID:23387756

  14. [Mn(III)(Schiff base)]?[Re(IV)(CN)?], highly anisotropic 3D coordination framework: synthesis, crystal structure, magnetic investigations, and theoretical analysis.

    PubMed

    Samsonenko, Denis G; Paulsen, Carley; Lhotel, Elsa; Mironov, Vladimir S; Vostrikova, Kira E

    2014-10-01

    A new highly anisotropic coordination heterobimetallic polymer [Mn(III)(Schiff-base)]3[Re(IV)(CN)7] was synthesized and characterized structurally and magnetically. The single crystal X-ray analysis has revealed that this is the first framework among the complexes composed of homoleptic cyanometallate and Mn(III) complex of the tetradentate Schiff base ligand. A formation of 3D assembly is possible due to both the pentagonal bipyrimidal geometry of the cyanometallate unit and suitable size of constituents: [Re(CN)7](3-) and [Mn(III)(acacen)](+), where acacen = N,N'-ethylenebis(acetylacetoneiminato). The powder and crystal magnetic studies show that the compound undergoes an antiferromagnetic ordering of a complicated character below Neel temperature of 13 K, and exhibits a metamagnetic behavior and strong magnetic anisotropy similar to those observed in related 3D Mn(II)-[Mo(CN)7](4-) systems. Unusual magnetic properties of [Mn(III)(acacen)]3[Re(IV)(CN)7] (1) originate from an interplay of Re-Mn anisotropic spin coupling and ZFS effect of Mn(III) ions with a noncollinear orientation of the local magnetic axes in the cyano-bridged 3D network. A theoretical model of anisotropic spin coupling between orbitally degenerate [Re(IV)(CN)7](3-) complexes and Mn(III) ions is developed, and specific microscopic mechanisms of highly anisotropic spin coupling in Re(IV)-CN-Mn(III) linkages in complex 1 are analyzed in detail. PMID:25250555

  15. Identifying factors likely to influence compliance with diagnostic imaging guideline recommendations for spine disorders among chiropractors in North America: a focus group study using the Theoretical Domains Framework

    PubMed Central

    2012-01-01

    Background The Theoretical Domains Framework (TDF) was developed to investigate determinants of specific clinical behaviors and inform the design of interventions to change professional behavior. This framework was used to explore the beliefs of chiropractors in an American Provider Network and two Canadian provinces about their adherence to evidence-based recommendations for spine radiography for uncomplicated back pain. The primary objective of the study was to identify chiropractors’ beliefs about managing uncomplicated back pain without x-rays and to explore barriers and facilitators to implementing evidence-based recommendations on lumbar spine x-rays. A secondary objective was to compare chiropractors in the United States and Canada on their beliefs regarding the use of spine x-rays. Methods Six focus groups exploring beliefs about managing back pain without x-rays were conducted with a purposive sample. The interview guide was based upon the TDF. Focus groups were digitally recorded, transcribed verbatim, and analyzed by two independent assessors using thematic content analysis based on the TDF. Results Five domains were identified as likely relevant. Key beliefs within these domains included the following: conflicting comments about the potential consequences of not ordering x-rays (risk of missing a pathology, avoiding adverse treatment effects, risks of litigation, determining the treatment plan, and using x-ray-driven techniques contrasted with perceived benefits of minimizing patient radiation exposure and reducing costs; beliefs about consequences); beliefs regarding professional autonomy, professional credibility, lack of standardization, and agreement with guidelines widely varied ( social/professional role & identity); the influence of formal training, colleagues, and patients also appeared to be important factors ( social influences); conflicting comments regarding levels of confidence and comfort in managing patients without x-rays ( belief about capabilities); and guideline awareness and agreements ( knowledge). Conclusions Chiropractors’ use of diagnostic imaging appears to be influenced by a number of factors. Five key domains may be important considering the presence of conflicting beliefs, evidence of strong beliefs likely to impact the behavior of interest, and high frequency of beliefs. The results will inform the development of a theory-based survey to help identify potential targets for behavioral-change strategies. PMID:22938135

  16. Exceptional H2 sorption characteristics in a Mg(2+)-based metal-organic framework with small pores: insights from experimental and theoretical studies.

    PubMed

    Pham, Tony; Forrest, Katherine A; Falcão, Eduardo H L; Eckert, Juergen; Space, Brian

    2016-01-21

    Experimental sorption measurements, inelastic neutron scattering (INS), and theoretical studies of H2 sorption were performed in ?-[Mg3(O2CH)6], a metal-organic framework (MOF) that consists of a network of Mg(2+) ions coordinated to formate ligands. The experimental H2 uptake at 77 K and 1.0 atm was observed to be 0.96 wt%, which is quite impressive for a Mg(2+)-based MOF that has a BET surface area of only 150 m(2) g(-1). Due to the presence of small pore sizes in the MOF, the isosteric heat of adsorption (Qst) value was observed to be reasonably high for a material with no open-metal sites (ca. 7.0 kJ mol(-1)). The INS spectra for H2 in ?-[Mg3(O2CH)6] is very unusual for a porous material, as there exist several different peaks that occur below 10 meV. Simulations of H2 sorption in ?-[Mg3(O2CH)6] revealed that the H2 molecules sorbed at three principal locations within the small pores of the framework. It was discovered through the simulations and two-dimensional quantum rotation calculations that different groups of peaks correspond to particular sorption sites in the material. However, for H2 sorbed at a specific site, it was observed that differences in the positions and angular orientations led to distinctions in the rotational tunnelling transitions; this led to a total of eight identified sites. An extremely high rotational barrier was calculated for H2 sorbed at the most favorable site in ?-[Mg3(O2CH)6] (81.59 meV); this value is in close agreement to that determined using an empirical phenomenological model (75.71 meV). This rotational barrier for H2 exceeds those for various MOFs that contain open-metal sites and is currently the highest yet for a neutral MOF. This study highlights the synergy between experiment and theory to extract useful and important atomic level details on the remarkable sorption mechanism for H2 in a MOF with small pore sizes. PMID:26673530

  17. Effect of temperature on formation of two new lanthanide metal-organic frameworks: Synthesis, characterization and theoretical studies of Tm(III)-succinate

    SciTech Connect

    Oliveira, Carlos Alberto F. de; Silva, Fausthon Fred da; Malvestiti, Ivani; Malta, Valeria Rodrigues dos S.; Dutra, Jose Diogo L.; Costa, Nivan B. da; Freire, Ricardo O.; Junior, Severino A.

    2013-01-15

    Two new metal-organic frameworks (MOFs) have been synthesized under different hydrothermal conditions and characterized by single-crystal X-ray diffraction, infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy and elemental analysis. Compound 1, crystallized in space group P1-bar with the formula [Tm{sub 2}(L){sub 3}(H{sub 2}O){sub 2}]{center_dot}H{sub 2}O, (H{sub 2}L=succinic acid), has triclinic cell parameters of a=7.61780(10), b=10.58050(10), c=12.71030(10), {alpha}=95.3130(10), {beta}=107.4370(10), {gamma}=111.0960(10) and a cell volume of 888.446(16) A{sup 3}. Compound 2, crystallized in space group I2/a with the same formula, is monoclinic, with cell parameters of a=13.77020(10), b=7.63170(10), c=17.2410(2), {beta}=101.303(10) and a cell volume of 1776.72(3) A{sup 3}. The results of this work indicate that a flexible succinate ligand that provides several modes of coordination can lead to different conformations, depending on the temperature used in the reaction. In the theoretical part of this study, semiempirical quantum chemistry methods using AM1, PM3 and PM6 models are employed to predict the structure of MOFs, calculate the geometric and crystallographic parameters, and make comparisons with experimental data. - Graphical abstract: Scheme of obtaining [Tm{sub 2}(C{sub 4}H{sub 4}O{sub 4}){sub 3}(H{sub 2}O){sub 2}]H{sub 2}O in two different crystalline phases under the influence of reaction temperature. Highlights: Black-Right-Pointing-Pointer Was synthesized new MOFs based on Tm{sup 3+} ions and succinic acid in different temperature. Black-Right-Pointing-Pointer The change in the temperature leads to two compounds with different crystalline systems. Black-Right-Pointing-Pointer The Sparkle AM1, PM3 and PM6 models were used to comparison of the theoretical and experimental cell.

  18. Quantum mechanical design of efficient second-order nonlinear optical materials based on heteroaromatic imido-substituted hexamolybdates: first theoretical framework of POM-based heterocyclic aromatic rings.

    PubMed

    Janjua, Muhammad Ramzan Saeed Ashraf

    2012-11-01

    This work was inspired by a previous report (Janjua et al. J. Phys. Chem. A 2009, 113, 3576-3587) in which the nonlinear-optical (NLO) response strikingly improved with an increase in the conjugation path of the ligand and the nature of hexamolybdates (polyoxometalates, POMs) was changed into a donor by altering the direction of charge transfer with a second aromatic ring. Herein, the first theoretical framework of POM-based heteroaromatic rings is found to be another class of excellent NLO materials having double heteroaromatic rings. First hyperpolarizabilities of a large number of push-pull-substituted conjugated systems with heteroaromatic rings have been calculated. The ? components were computed at the density functional theory (DFT) level (BP86 geometry optimizations and LB94 time-dependent DFT). The largest ? values are obtained with a donor (hexamolybdates) on the benzene ring and an acceptor (-NO(2)) on pyrrole, thiophene, and furan rings. The pyrrole imido-substituted hexamolybdate (system 1c) has a considerably large first hyperpolarizability, 339.00 × 10(-30) esu, and it is larger than that of (arylimido)hexamolybdate, calculated as 0.302 × 10(-30) esu (reference system 1), because of the double aromatic rings in the heteroaromatic imido-substituted hexamolybdates. The heteroaromatic rings act as a conjugation bridge between the electron acceptor (-NO(2)) and donor (polyanion). The introduction of an electron donor into heteroaromatic rings significantly enhances the first hyperpolarizabilities because the electron-donating ability is substantially enhanced when the electron donor is attached to the heterocyclic aromatic rings. Interposing five-membered auxiliary fragments between strong donor (polyanion) or acceptor (-NO(2)) groups results in a large computed second-order NLO response. The present investigation provides important insight into the NLO properties of (heteroaromatic) imido-substituted hexamolybdate derivatives because these compounds exhibit enhanced hyperpolarizabilities compared to typical NLO arylimido hexamolybdates and heterocyclic aromatic rings reported in the literature. PMID:23075454

  19. Forensic intelligence framework. Part II: Study of the main generic building blocks and challenges through the examples of illicit drugs and false identity documents monitoring.

    PubMed

    Baechler, Simon; Morelato, Marie; Ribaux, Olivier; Beavis, Alison; Tahtouh, Mark; Kirkbride, K Paul; Esseiva, Pierre; Margot, Pierre; Roux, Claude

    2015-05-01

    The development of forensic intelligence relies on the expression of suitable models that better represent the contribution of forensic intelligence in relation to the criminal justice system, policing and security. Such models assist in comparing and evaluating methods and new technologies, provide transparency and foster the development of new applications. Interestingly, strong similarities between two separate projects focusing on specific forensic science areas were recently observed. These observations have led to the induction of a general model (Part I) that could guide the use of any forensic science case data in an intelligence perspective. The present article builds upon this general approach by focusing on decisional and organisational issues. The article investigates the comparison process and evaluation system that lay at the heart of the forensic intelligence framework, advocating scientific decision criteria and a structured but flexible and dynamic architecture. These building blocks are crucial and clearly lay within the expertise of forensic scientists. However, it is only part of the problem. Forensic intelligence includes other blocks with their respective interactions, decision points and tensions (e.g. regarding how to guide detection and how to integrate forensic information with other information). Formalising these blocks identifies many questions and potential answers. Addressing these questions is essential for the progress of the discipline. Such a process requires clarifying the role and place of the forensic scientist within the whole process and their relationship to other stakeholders. PMID:25800712

  20. Teaching Main Idea Comprehension.

    ERIC Educational Resources Information Center

    Baumann, James F., Ed.

    Intended to help classroom teachers, curriculum developers, and researchers, this book provides current information on theoretical and instructional aspects of main idea comprehension. Titles and authors are as follows: "The Confused World of Main Idea" (James W. Cunningham and David W. Moore); "The Comprehension of Important Information in…

  1. A quantitative synthesis of the medicinal ethnobotany of the Malinké of Mali and the Asháninka of Peru, with a new theoretical framework

    PubMed Central

    Bletter, Nathaniel

    2007-01-01

    Background Although ethnomedically and taxonomically guided searches for new medicinal plants can improve the percentage of plants found containing active compounds when compared to random sampling, ethnobotany has fulfilled little of its promise in the last few decades to deliver a bounty of new, laboratory-proven medicinal plants and compounds. It is quite difficult to test, isolate, and elucidate the structure and mechanism of compounds from the plethora of new medicinal plant uses described each year with limited laboratory time and resources and the high cost of clinical trials of new drug candidates. Methods A new quantitative theoretical framework of mathematical formulas called "relational efficacy" is proposed that should narrow down this search for new plant-derived medicines based on the hypothesis that closely related plants used to treat closely related diseases in distantly related cultures have a higher probability of being effective because they are more likely to be independent discoveries of similar plant compounds and disease mechanisms. A prerequisite to this hypothesis, the idea that empirical testing in traditional medicine will lead to choosing similar medicinal plants and therefore the medicinal flora of two distant cultures will prove to be more similar than their general flora, is tested using resampling statistics on cross-cultural field data of the plants used by the Malinké of Mali and the Asháninka of Peru to treat the diseases malaria, African sleeping sickness, Chagas' disease, leishmaniasis, diabetes, eczema, asthma, and uterine fibroids. Results In this case, the similarity of the medicinal floras is found to be significantly greater than the similarity of the general floras, but only when the diseases in question are grouped into the categories of parasitic and autoimmune diseases. Conclusion If the central theoretical framework of this hypothesis is shown to be true, it will allow the synthesis of medicinal plant information from around the world to pinpoint the species with the highest potential efficacy to take into the laboratory and analyze further, ultimately saving much field and laboratory time and resources. Spanish abstract Las búsquedas que utilizan la etnomedicina y la taxonomía para descubrir nuevas plantas medicinales, pueden aumentar la probabilidad de éxito de encontrar compuestos químicos activos en plantas, en comparación con las búsquedas aleatorias. A pesar de lo anterior, en las últimas décadas, la etnobotánica no ha cumplido con las expectativas de proveer numerosas plantas medicinales y químicos nuevos una vez examinados en el laboratorio. Cada año se describen una plétora de plantas medicinales y sus usos, sin embargo las limitaciones de tiempo y recursos en los laboratorios, unidos al alto coste de los ensayos clínicos de las drogas potenciales, hacen muy difícil probar, aislar, y elucidar la estructura y el mecanismo de los compuestos de estas plantas. Se propone un nuevo marco teórico cuantitativo cuyo fin es focalizar la búsqueda de nueva plantas medicinales. Este marco teórico está basado en la hipótesis que las plantas cercanamente relacionadas, usadas para tratar enfermedades cercanamente relacionadas en culturas distantemente relacionadas, tienen una eficacia potencial más alta, debido a que es más probable que estos hallazgos sean descubrimientos independientes de compuestos químicos similares. Parte de esta hipótesis, que las escogencias racionales se hacen para elegir plantas medicinales similares y que la flora medicinal de dos culturas distantes es más similar que su flora general, se probó usando métodos estadísticos de remuestreo con datos de campo de la comunidad Malinké de Malí y de la Asháninka de Perú, y las enfermedades de paludismo, enfermedad africana del sueño, enfermedad de Chagas, leishmania, diabetes, eczema, asma, y fibromas uterinos. Se encontró, en este caso, que la similitud de las floras medicinales es significativamente mayor a la similitud de las floras generales, solamente cuando las enfermedades analizadas se agruparon en las categorías de enfermedades parasitarias y enfermedades autoinmunes. Si se demostrara que las otras partes de esta hipótesis son ciertas, se podría sintetizar la información sobre plantas medicinales alrededor del mundo, para establecer así las plantas potencialmente más eficaces para llevarlas al laboratorio y analizarlas más profundamente. French abstract Par rapport aux recherches menées de façon aléatoire, les recherches effectuées par des critères ethnobotaniques et taxonomiques ont de meilleures chances à découvrir de nouvelles plantes médicinales à produit chimique actifs. Pendant les dernières décennies pourtant, l'ethnobotanique a réalisé peu de ces promesses à révéler un grand nombre de plantes médicinales et de nouveaux produits chimiques, testés au laboratoire. Avec les ressources limitées pour la recherche au laboratoire et le coût élevé des épreuves cliniques pour trouver de nouveaux candidats aux médicaments, il est difficile d'étudier, d'isoler et d'élucider la structure et le mécanisme des produits chimiques de chacune des nombreuses plantes médicinales (et les utilisations de ces plantes) décrites chaque année. Nous proposons une nouvelle technique théorique et quantitative pour préciser la recherche de nouvelles plantes médicinales; elle est basée sur l'hypothèse que les plantes étroitement apparentées, employées pour traiter les maladies étroitement apparentées dans les cultures très éloignées les unes des autres, ont une potentialité d'efficacité supérieure parce qu'elles représentent la découverte indépendante des propriétés chimiques semblables des plantes. Une partie de cette hypothèse-qui démontre que la sélection des plantes médicinales semblables est un choix rationnel et qu'il y a davantage de ressemblance dans la flore médicinale de deux cultures éloignées que dans leur flore générale-est examinée par un re-échantillonnage des données de recherches effectuées parmi les Malinké au Mali et les Asháninka au Pérou, en particulier sur la malaria, la maladie africaine du sommeil, la maladie de Chagas, la leishmania, le diabète, l'eczéma, l'asthme et les fibromes utérins. Dans ces cas précis, la similitude de la flore médicinale s'avère sensiblement plus grande que la similitude de la flore générale, mais seulement quand les maladies en question sont regroupées ensemble comme maladies parasitaires et auto-immunitaires. Si cette hypothèse est prouvée, elle permettra la synthèse des informations recueillies sur les plantes médicinales du monde entier pour en sélectionner de façon plus précise celles qui sont les plus efficaces et qui méritent analyse plus approfondie au laboratoire. Asháninka abstract Aayiantyarori iròpero aavintane, ontzimatye ancovacovatero ayotero ovaqueraripaye incashi iyoyetziri ashaninka, ayotzityaro aajatzi iyotane viracocha paitachari "quimica" ancantero aaca oshintsinka inchashipaye. Atziri yotacotzirori cametsa, ishtoriajacotzirori iyotane ashaninkapaye te iroñàrantero maaroni ocaratzi yamenacotaqueri laboratorioki. Aaviantyarori cametsa, ayotacotero aavintarontsiyetatsiri osamani antzimaventero ishtoriatacotaro, aajatzi osheki opinata ampinaventero aparopaye inchashi, acoviriqui ayotacotero, osaretsikipaye. Tzimatsi ovaquerari quenquishiriantsitatsiri ero opinata osheki ashitoriatacotero aparopaye inchashi, asampiyetatyrey pashinipaye atziri saicatsiri intaina puitarika inchasshi yavintari, ajatzirica oshiyaro ayotzi aaca, quemetachari atziri saikatsiri nampitsiki malinke aajatzi ishiyari ashaninka saicatsiri peruki, tzimatsi inchashi aajatzi yaavintari osheki okamètsatzi aririka anteri mantsiyarentsi icantaitziri ompetarentsi catsirentsi, pochokirentsi, patsarontsi(matatsi) ashipetate maaroni, ampochavathate, ancainikentsite, oncatsithakite tsinani. Aririka añaker aajatzi ahiyaro inchashi yaavintayetari pashinipaye atziri intainasatzi irdotake ahitoriatacoperoteri anàashityard aavintarontsi ovamairiri shithanentsi, onàshitaavintarontsi tzicaacoventairi ero antane mantsiyarentsi. Omanperotatyarica iròperotzi avintarontsi, oshitovake laboratorioki aritaque iyoitanaquero maaroni quipatsiki iroperori avintarontsi. PMID:18053260

  2. MAINE POPULATION

    EPA Science Inventory

    MEPOP250 depicts Maine's 1950-1990 population data by town or Census in unorganized territories. Populations were compiled from US Census Bureau data where available or from Maine Municipal Information (mainly for older records). Unorganized towns with very low or zero pop...

  3. Cultural targeting and tailoring of shared decision making technology: a theoretical framework for improving the effectiveness of patient decision aids in culturally diverse groups.

    PubMed

    Alden, Dana L; Friend, John; Schapira, Marilyn; Stiggelbout, Anne

    2014-03-01

    Patient decision aids are known to positively impact outcomes critical to shared decision making (SDM), such as gist knowledge and decision preparedness. However, research on the potential improvement of these and other important outcomes through cultural targeting and tailoring of decision aids is very limited. This is the case despite extensive evidence supporting use of cultural targeting and tailoring to improve the effectiveness of health communications. Building on prominent psychological theory, we propose a two-stage framework incorporating cultural concepts into the design process for screening and treatment decision aids. The first phase recommends use of cultural constructs, such as collectivism and individualism, to differentially target patients whose cultures are known to vary on these dimensions. Decision aid targeting is operationalized through use of symbols and values that appeal to members of the given culture. Content dimensions within decision aids that appear particularly appropriate for targeting include surface level visual characteristics, language, beliefs, attitudes and values. The second phase of the framework is based on evidence that individuals vary in terms of how strongly cultural norms influence their approach to problem solving and decision making. In particular, the framework hypothesizes that differences in terms of access to cultural mindsets (e.g., access to interdependent versus independent self) can be measured up front and used to tailor decision aids. Thus, the second phase in the framework emphasizes the importance of not only targeting decision aid content, but also tailoring the information to the individual based on measurement of how strongly he/she is connected to dominant cultural mindsets. Overall, the framework provides a theory-based guide for researchers and practitioners who are interested in using cultural targeting and tailoring to develop and test decision aids that move beyond a "one-size fits all" approach and thereby, improve SDM in our multicultural world. PMID:24606791

  4. To Be Cared for and to Care: Understanding Theoretical Conceptions of Care as a Framework for Effective Inclusion in Early Childhood Education and Care

    ERIC Educational Resources Information Center

    Wood, Rebecca

    2015-01-01

    This article argues that incorporating theoretical conceptions of care into Early Childhood Education and Care (ECEC) programmes creates a foundation for achieving the effective inclusion of children with disabilities. Critical examinations of the origins of care theory and current conceptions of care are used to consider the differing valuation…

  5. The Degree of Applying the Theoretical Frameworks of Child-Raising Specialty Courses in the Field of Training among the Female Students of Princess Alia University College

    ERIC Educational Resources Information Center

    Tweeikat, Mashhour Mohammad; AL-Kaddah, Muhammad Ibrahim

    2014-01-01

    This paper aims at studying to what extent the female students in Child Education department at Princess Alia University College manage to apply the theoretical part in field training program. The data, which is the scope of this study, consists of 42 staff members and 36 educational supervisors responsible for the program. The two researchers…

  6. To Be Cared for and to Care: Understanding Theoretical Conceptions of Care as a Framework for Effective Inclusion in Early Childhood Education and Care

    ERIC Educational Resources Information Center

    Wood, Rebecca

    2015-01-01

    This article argues that incorporating theoretical conceptions of care into Early Childhood Education and Care (ECEC) programmes creates a foundation for achieving the effective inclusion of children with disabilities. Critical examinations of the origins of care theory and current conceptions of care are used to consider the differing valuation…

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

    NASA Astrophysics Data System (ADS)

    Marques, Lippy F.; Correa, Charlane C.; Ribeiro, Sidney J. L.; dos Santos, Molíria V.; Dutra, José Diogo L.; Freire, Ricardo O.; Machado, Flávia C.

    2015-07-01

    In this paper, the synthesis of three new metal-organic frameworks of lanthanides (LnMOFs) {[Ln2(2,5-tdc)3(dmso)2]·H2O}n (Ln=Ho (1); Gd (2); Eu (3); 2,5-tdc=2,5-thiophenedicarboxylate anion; dmso=dimethylsulfoxide), and their complete characterization, including single crystal X-ray diffraction, FTIR spectroscopy and thermogravimetric analysis are reported. In especial, photophysical properties of Eu(III) complex have been studied in detail via both theoretical and experimental approaches. Crystal structure of (1) reveals that each lanthanide ion is seven-coordinated by oxygen atoms in an overall distorted capped trigonal - prismatic geometry. The 2,5-tdc2- ligands connect four Ln(III) centers, adopting (?1-?1)-(?1-?1)-?4 coordination mode, generating an 8-connected uninodal 3D network. In addition, theoretical studies for Eu(III) complex were performed using the Sparkle model for lanthanide complexes.

  8. Comment on "A theoretical framework for quantitatively characterizing sound field diffusion based on scattering coefficient and absorption coefficient of walls" [J. Acoust. Soc. Am. 128, 1140-1148 (2010)] (L).

    PubMed

    Omoto, Akira

    2013-01-01

    The relationship between the acoustic scattering characteristics of materials and the degree of diffusion in enclosed acoustic spaces has recently attracted considerable research attention. Hanyu [J. Acoust. Soc. Am. 128(3), 1140-1148 (2010)] introduced a theoretical framework, in which the diffusion time in an enclosure is expressed as a function of a material's average scattering coefficient. In this letter, a modification of this theory is proposed. The decay process of the sound energy through scattering is divided into discrete sub-processes, specifically, a purely scattering process, and alternating scattering and specular reflections. The behavior of each process is examined for different scattering coefficients. PMID:23297877

  9. MAINE AQUIFERS

    EPA Science Inventory

    AQFRS24 contains polygons of significant aquifers in Maine (glacial deposits that are a significant ground water resource) mapped at a scale 1:24,000. This statewide coverage was derived from aquifer boundaries delineated and digitized by the Maine Geological Survey from data com...

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

    PubMed Central

    Van Zyl, Hendra; Kotze, Marike; Laubscher, Ria

    2014-01-01

    eHealth has been identified as a useful approach to disseminate HIV/AIDS information. Together with Consumer Health Informatics (CHI), the Web-to-Public Knowledge Transfer Model (WPKTM) has been applied as a theoretical framework to identify consumer needs for AfroAIDSinfo, a South African Web portal. As part of the CHI practice, regular eSurveys are conducted to determine whether these needs are changing and are continually being met. eSurveys show high rates of satisfaction with the content as well as the modes of delivery. The nature of information is thought of as reliable to reuse; both for education and for referencing of information. Using CHI and the WPKTM as a theoretical framework, it ensures that needs of consumers are being met and that they find the tailored methods of presenting the information agreeable. Combining ICTs and theories in eHealth interventions, this approach can be expanded to deliver information in other sectors of public health. PMID:24686487

  11. Using a theoretical framework to investigate whether the HIV/AIDS information needs of the AfroAIDSinfo Web portal members are met: a South African eHealth study.

    PubMed

    Van Zyl, Hendra; Kotze, Marike; Laubscher, Ria

    2014-04-01

    eHealth has been identified as a useful approach to disseminate HIV/AIDS information. Together with Consumer Health Informatics (CHI), the Web-to-Public Knowledge Transfer Model (WPKTM) has been applied as a theoretical framework to identify consumer needs for AfroAIDSinfo, a South African Web portal. As part of the CHI practice, regular eSurveys are conducted to determine whether these needs are changing and are continually being met. eSurveys show high rates of satisfaction with the content as well as the modes of delivery. The nature of information is thought of as reliable to reuse; both for education and for referencing of information. Using CHI and the WPKTM as a theoretical framework, it ensures that needs of consumers are being met and that they find the tailored methods of presenting the information agreeable. Combining ICTs and theories in eHealth interventions, this approach can be expanded to deliver information in other sectors of public health. PMID:24686487

  12. Maine Ingredients

    ERIC Educational Resources Information Center

    Waters, John K.

    2009-01-01

    This article features Maine Learning Technology Initiative (MLTI), the nation's first-ever statewide 1-to-1 laptop program which marks its seventh birthday by expanding into high schools, providing an occasion to celebrate--and to examine the components of its success. The plan to put laptops into the hands of every teacher and student in grades 7…

  13. MAINE HYDROGRAPHY

    EPA Science Inventory

    Hydronet_me24 and Hydropoly_me24 depict Maine's hydrography data, based on 8-digit hydrological unit codes (HUC's) at the 1:24,000 scale. Some New Hampshire and New Brunswick hydrography data are also included. The NHD hydrography data was compiled from previous ArcIn...

  14. MAINE WOODLOTS

    EPA Science Inventory

    MEOWN250 describes industrial, non-industrial, and public woodlot ownership in Maine at 1:250,000 scale. Industrial owners are those having at least one primary wood processing facility. Non-industrial owners are those with no primary wood processing facility. Public ownership...

  15. A theoretical framework to distinguish direct and indirect anthropogenic perturbations of the terrestrial carbon cycle; and its implications in the definition of "emissions from land-use change"

    NASA Astrophysics Data System (ADS)

    Gasser, Thomas; Ciais, Philippe; Viovy, Nicolas

    2013-04-01

    We present a theoretical analysis of the net land-to-atmosphere CO2 flux, so as to discuss possible definitions of "emissions from land-use change" at global scale. Our work is based on the fact that the terrestrial carbon cycle is affected by two anthropogenic perturbations. The first is the perturbation of the global Carbon-Climate-Nitrogen (CCN) system as observed with elevated CO2, climate change and increased nitrogen deposition; it impacts the intensive parameters of the terrestrial biosphere. The second is the Land-Use and Land-Use Change (LUC) perturbation induced by human activities; impacting the extensive parameters of the biosphere. Previous global carbon budgets tried to separate these two perturbations by defining two CO2 fluxes: the emissions from land-use change (LUC perturbation) and the land sink (CCN perturbation). Here, through successive mathematical demonstrations, we isolate four (not two) generic components of the net land-to-atmosphere CO2 flux. The two first components are the fluxes that would be observed if only one perturbation occurred. The two other components are due to the coupling of the CCN and LUC perturbations, highlighting the non-linear behavior of the terrestrial carbon cycle. Thanks to this, we introduce three possible definitions of "emissions from land-use change", that are indeed used in the scientific literature (often without clear distinctions), and we draw conclusions as for their absolute and relative behaviors. Finally, we illustrate our theoretical results thanks to two models: a simple carbon-climate model using a book-keeping module to estimate emissions from land-use change (named OSCAR), and the spatialized land-surface model ORCHIDEE. Our preliminary results show that comparing results from studies that do not use the same definition can lead to a bias of up to 20% between estimates of "emissions from land-use change". This makes our study of major interest to reconcile modeling and observation of "emissions from land-use change", and ultimately to distinguish direct and indirect effects of anthropogenic activities.

  16. Beyond safety outcomes: An investigation of the impact of safety climate on job satisfaction, employee engagement and turnover using social exchange theory as the theoretical framework.

    PubMed

    Huang, Yueng-Hsiang; Lee, Jin; McFadden, Anna C; Murphy, Lauren A; Robertson, Michelle M; Cheung, Janelle H; Zohar, Dov

    2016-07-01

    Safety climate, a measure of the degree to which safety is perceived by employees to be a priority in their company, is often implicated as a key factor in the promotion of injury-reducing behavior and safe work environments. Using social exchange theory as a theoretical basis, this study hypothesized that safety climate would be related to employees' job satisfaction, engagement, and turnover rate, highlighting the beneficial effects of safety climate beyond typical safety outcomes. Survey data were collected from 6207 truck drivers from two U.S. trucking companies. The objective turnover rate was collected one year after the survey data collection. Results showed that employees' safety climate perceptions were linked to employees' level of job satisfaction, engagement, and objective turnover rate, thus supporting the application of social exchange theory. Job satisfaction was also a significant mediator between safety climate and the two human resource outcomes (i.e., employee engagement and turnover rate). This study is among the first to assess the impact of safety climate beyond safety outcomes among lone workers (using truck drivers as an exemplar). PMID:26611987

  17. Proceedings of the second International Workshop on the Dark Side of the Universe : experimental efforts and theoretical framework, Roma, Italy, 13-14 November 1995

    NASA Astrophysics Data System (ADS)

    Bernabei, Rita; Incicchitti, Antonella

    1996-10-01

    The Table of Contents for the book is as follows: * Preface * Ashophysics * Dark Matter in the Universe: A Review * Low-Surface-Density Galaxies and the Modified Dynamics * Particle Creation by Topological Defects * Clusters of Galaxies as Probes of Dark Matter Scenarios * Baryonic Dark Matter in the Galactic Halo * Large Scale Simulations in Dark Matter Scenarios * Dark Matter from Dynamics on Large Scales * The Baryonic Mass Density of Cool Gas in the Universe * Baryonic DM Searches * Theory: * Baryons in the Halo * Microlensing Implications for Halo Dark Matter * MACHOs and Molecular Clouds as Candidates for Halo Dark Matter * Interpreting the Microlensing Observations * Microlensing Rates from Galactic Models with Radial Anisotropy in Velocity Space * Experiments: * Last Results from EROS Experiment * AGAPE, a Microlensing Search in the Direction of M31: Status Report * Neutrinos * The NOMAD Experiment at the CERN SPS: A Status Report * The CHORUS Neutrino Oscillation Experiment and the Prospects for the Tau-Neutrino Mass * Axions * A Search for Halo Axions * Theory * Neutralino Dark Matter: An Overview * New Developments in SUSY Models * The Difficulties of Decaying Dark Matter as Source of UV Background * Search at Accelerators * SUSY and Dark Matter Searches at the LHC * Low Radioactivity Techniques * Low Background Technique Measurements at Laboratori Nazionali del Gran Sasso * Radiopurification of NaI and Its Application to Dark Matter and Neutrino Experiments * Radiopurity in Xe and CF4 * WIMP Direct Searches * Theoretical Expectations for Direct Detection of SUSY Dark Matter * Heidelberg Dark Matter Search * Search for WIMPs with Large Volume Ge Detectors at Baksan Neutrino Observatory * Dark Matter Limits from the Nal Detectors at Boulby Mine * Dark Matter Search with Low Activity Crystals * Improved Limits on WIMP Search with Low Activity NaI(Tl) at Gran Sasso * Preliminary Results on WIMP Search Enriched with Xenon at Gran Sasso * Preliminary Results on Direct Detection of WIMPs with a TeO2 Bolometer * Status of the Cryogenic Dark Matter Search * Status of the CRESST Dark Matter Experiment * The ORPHEUS Dark Matter Detector * Dark Matter Search with Moderately Superheated Liquids * Search for WIMP's with the Multicell Proportional Counter * WIMP Indirect Searches * Indirect Detection of Supersymmetric Dark Matter * Preliminary Results on a Search for Neutrinos from the Center of the Earth with the Baikal Underwater Telescope * Search for Magnetic Monopoles with Deep Underwater Cherenkov Detectors at Lake Baikal * Search for Magnetic Monopoles with the O Detector at Gran Sasso * NESTOR Possibilities in Detection of Non-baryonic Dark Matter * Astroparticle Studies of the Physical Nature of Dark, Decaying and Annihilating Matter in the Universe (AstroDAMUS Project) * Gamma Ray Detectors and Dark Matter * Pulsars' Period Deviation Due to Shapiro Phase Shift to Detect Dark Matter * List of Participants

  18. Theoretical Mathematics

    NASA Astrophysics Data System (ADS)

    Stöltzner, Michael

    Answering to the double-faced influence of string theory on mathematical practice and rigour, the mathematical physicists Arthur Jaffe and Frank Quinn have contemplated the idea that there exists a `theoretical' mathematics (alongside `theoretical' physics) whose basic structures and results still require independent corroboration by mathematical proof. In this paper, I shall take the Jaffe-Quinn debate mainly as a problem of mathematical ontology and analyse it against the backdrop of two philosophical views that are appreciative towards informal mathematical development and conjectural results: Lakatos's methodology of proofs and refutations and John von Neumann's opportunistic reading of Hilbert's axiomatic method. The comparison of both approaches shows that mitigating Lakatos's falsificationism makes his insights about mathematical quasi-ontology more relevant to 20th century mathematics in which new structures are introduced by axiomatisation and not necessarily motivated by informal ancestors. The final section discusses the consequences of string theorists' claim to finality for the theory's mathematical make-up. I argue that ontological reductionism as advocated by particle physicists and the quest for mathematically deeper axioms do not necessarily lead to identical results.

  19. Gyrokinetic framework for Neoclassical Tearing Modes

    NASA Astrophysics Data System (ADS)

    Tronko, Natalia; Wilson, Howard; Brizard, Alain

    2013-10-01

    We are developing a new theoretical framework based on the Hamiltonian Gyrokinetics for description of the Neoclassical Tearing Modes dynamics. The main advantage of this approach is the possibility of systematically including effects of magnetic geometry as well as magnetic field fluctuations due to the presence of a magnetic island. Moreover it makes it possible to systematically compute the expression for the polarization current as well as including FLR effects. This work represents an extension of previous drift-kinetic models for NTMs.

  20. Towards general information theoretical representations of database problems

    SciTech Connect

    Joslyn, C.

    1997-06-01

    General database systems are described from the General Systems Theoretical (GST) framework. In this context traditional information theoretical (statistical) and general information theoretical (fuzzy measure and set theoretical, possibilistic, and random set theoretical) representations are derived. A preliminary formal framework is introduced.

  1. Main Report

    PubMed Central

    2006-01-01

    Background: States vary widely in their use of newborn screening tests, with some mandating screening for as few as three conditions and others mandating as many as 43 conditions, including varying numbers of the 40+ conditions that can be detected by tandem mass spectrometry (MS/MS). There has been no national guidance on the best candidate conditions for newborn screening since the National Academy of Sciences report of 19751 and the United States Congress Office of Technology Assessment report of 1988,2 despite rapid developments since then in genetics, in screening technologies, and in some treatments. Objectives: In 2002, the Maternal and Child Health Bureau (MCHB) of the Health Resources and Services Administration (HRSA) of the United States Department of Health and Human Services (DHHS) commissioned the American College of Medical Genetics (ACMG) to: Conduct an analysis of the scientific literature on the effectiveness of newborn screening.Gather expert opinion to delineate the best evidence for screening for specified conditions and develop recommendations focused on newborn screening, including but not limited to the development of a uniform condition panel.Consider other components of the newborn screening system that are critical to achieving the expected outcomes in those screened. Methods: A group of experts in various areas of subspecialty medicine and primary care, health policy, law, public health, and consumers worked with a steering committee and several expert work groups, using a two-tiered approach to assess and rank conditions. A first step was developing a set of principles to guide the analysis. This was followed by developing criteria by which conditions could be evaluated, and then identifying the conditions to be evaluated. A large and broadly representative group of experts was asked to provide their opinions on the extent to which particular conditions met the selected criteria, relying on supporting evidence and references from the scientific literature. The criteria were distributed among three main categories for each condition: The availability and characteristics of the screening test;The availability and complexity of diagnostic services; andThe availability and efficacy of treatments related to the conditions. A survey process utilizing a data collection instrument was used to gather expert opinion on the conditions in the first tier of the assessment. The data collection format and survey provided the opportunity to quantify expert opinion and to obtain the views of a diverse set of interest groups (necessary due to the subjective nature of some of the criteria). Statistical analysis of data produced a score for each condition, which determined its ranking and initial placement in one of three categories (high scoring, moderately scoring, or low scoring/absence of a newborn screening test). In the second tier of these analyses, the evidence base related to each condition was assessed in depth (e.g., via systematic reviews of reference lists including MedLine, PubMed and others; books; Internet searches; professional guidelines; clinical evidence; and cost/economic evidence and modeling). The fact sheets reflecting these analyses were evaluated by at least two acknowledged experts for each condition. These experts assessed the data and the associated references related to each criterion and provided corrections where appropriate, assigned a value to the level of evidence and the quality of the studies that established the evidence base, and determined whether there were significant variances from the survey data. Survey results were subsequently realigned with the evidence obtained from the scientific literature during the second-tier analysis for all objective criteria, based on input from at least three acknowledged experts in each condition. The information from these two tiers of assessment was then considered with regard to the overriding principles and other technology or condition-specific recommendations. On the basis of this information, conditions were assigned to one of three categories as described above:Core Panel;Secondary Targets (conditions that are part of the differential diagnosis of a core panel condition.); andNot Appropriate for Newborn Screening (either no newborn screening test is available or there is poor performance with regard to multiple other evaluation criteria). ACMG also considered features of optimal newborn screening programs beyond the tests themselves by assessing the degree to which programs met certain goals (e.g., availability of educational programs, proportions of newborns screened and followed up). Assessments were based on the input of experts serving in various capacities in newborn screening programs and on 2002 data provided by the programs of the National Newborn Screening and Genetics Resource Center (NNSGRC). In addition, a brief cost-effectiveness assessment of newborn screening was conducted. Results: Uniform panel A total of 292 individuals determined to be generally representative of the regional distribution of the United States population and of areas of expertise or involvement in newborn screening provided a total of 3,949 evaluations of 84 conditions. For each condition, the responses of at least three experts in that condition were compared with those of all respondents for that condition and found to be consistent. A score of 1,200 on the data collection instrument provided a logical separation point between high scoring conditions (1,200–1,799 of a possible 2,100) and low scoring (<1,000) conditions. A group of conditions with intermediate scores (1,000–1,199) was identified, all of which were part of the differential diagnosis of a high scoring condition or apparent in the result of the multiplex assay. Some are identified by screening laboratories and others by diagnostic laboratories. This group was designated as a “secondary target” category for which the program must report the diagnostic result. Using the validated evidence base and expert opinion, each condition that had previously been assigned to a category based on scores gathered through the data collection instrument was reconsidered. Again, the factors taken into consideration were: 1) available scientific evidence; 2) availability of a screening test; 3) presence of an efficacious treatment; 4) adequate understanding of the natural history of the condition; and 5) whether the condition was either part of the differential diagnosis of another condition or whether the screening test results related to a clinically significant condition. The conditions were then assigned to one of three categories as previously described (core panel, secondary targets, or not appropriate for Newborn Screening). Among the 29 conditions assigned to the core panel are three hemoglobinopathies associated with a Hb/S allele, six amino acidurias, five disorders of fatty oxidation, nine organic acidurias, and six unrelated conditions (congenital hypothyroidism (CH), biotinidase deficiency (BIOT), congenital adrenal hyperplasia (CAH), classical galactosemia (GALT), hearing loss (HEAR) and cystic fibrosis (CF)). Twenty-three of the 29 conditions in the core panel are identified with multiplex technologies such as tandem mass spectrometry (MS/MS) or high pressure liquid chromatography (HPLC). On the basis of the evidence, six of the 35 conditions initially placed in the core panel were moved into the secondary target category, which expanded to 25 conditions. Test results not associated with potential disease in the infant (e.g., carriers) were also placed in the secondary target category. When newborn screening laboratory results definitively establish carrier status, the result should be made available to the health care professional community and families. Twenty-seven conditions were determined to be inappropriate for newborn screening at this time. Conditions with limited evidence reported in the scientific literature were more difficult to evaluate, quantify and place in one of the three categories. In addition, many conditions were found to occur in multiple forms distinguished by age-of-onset, severity, or other features. Further, unless a condition was already included in newborn screening programs, there was a potential for bias in the information related to some criteria. In such circumstances, the quality of the studies underlying the data such as expert opinion that considered case reports and reasoning from first principles determined the placement of the conditions into particular categories. Newborn screening program optimization – Assessment of the activities of newborn screening programs, based on program reports, was done for the six program components: education; screening; follow-up; diagnostic confirmation; management; and program evaluation. Considerable variation was found between programs with regard to whether particular aspects (e.g., prenatal education program availability, tracking of specimen collection and delivery) were included and the degree to which they are provided. Newborn screening program evaluation systems also were assessed in order to determine their adequacy and uniformity with the goal being to improve interprogram evaluation and comparison to ensure that the expected outcomes from having been identified in screening are realized. Conclusions: The state of the published evidence in the fast-moving worlds of newborn screening and medical genetics has not kept up with the implementation of new technologies, thus requiring the considerable use of expert opinion to develop recommendations about a core panel of conditions for newborn screening. Twenty-nine conditions were identified as primary targets for screening from which all components of the newborn screening system should be maximized. An additional 25 conditions were listed that could be identified in the course of screening for core panel conditions. Programs are obligated to establish a diagnosis and communicate the result to the health care provider and family. It is recognized that screening may not have been maximized for the detection of these secondary conditions but that some proportion of such cases may be found among those screened for core panel conditions. With additional screening, greater training of primary care health care professionals and subspecialists will be needed, as will the development of an infrastructure for appropriate follow-up and management throughout the lives of children who have been identified as having one of these rare conditions. Recommended actions to overcome barriers to an optimal newborn screening system include: The establishment of a national role in the scientific evaluation of conditions and the technologies by which they are screened;Standardization of case definitions and reporting procedures;Enhanced oversight of hospital-based screening activities;Long-term data collection and surveillance; andConsideration of the financial needs of programs to allow them to deliver the appropriate services to the screened population.

  2. Theoretical Frameworks for Studying Female Marriage Migrants

    ERIC Educational Resources Information Center

    Merali, Noorfarah

    2008-01-01

    Transnational marriages account for a significant proportion of family-based immigration to North America. An increasing number of immigrant men are choosing to marry women from their countries of origin, and an increasing number of nonimmigrant men are choosing to marry women from other countries. Existing studies on the experiences of foreign…

  3. Theoretical Frameworks to Guide School Improvement

    ERIC Educational Resources Information Center

    Evans, Lisa; Thornton, Bill; Usinger, Janet

    2012-01-01

    A firm grounding in change theory can provide educational leaders with an opportunity to orchestrate meaningful organizational improvements. This article provides an opportunity for practicing leaders to review four major theories of organizational change--continuous improvement, two approaches to organizational learning, and appreciative inquiry.…

  4. Theoretical Frameworks to Guide School Improvement

    ERIC Educational Resources Information Center

    Evans, Lisa; Thornton, Bill; Usinger, Janet

    2012-01-01

    A firm grounding in change theory can provide educational leaders with an opportunity to orchestrate meaningful organizational improvements. This article provides an opportunity for practicing leaders to review four major theories of organizational change--continuous improvement, two approaches to organizational learning, and appreciative inquiry.…

  5. Theoretical Frameworks for Multiscale Modeling and Simulation

    PubMed Central

    Zhou, Huan-Xiang

    2014-01-01

    Biomolecular systems have been modeled at a variety of scales, ranging from explicit treatment of electrons and nuclei to continuum description of bulk deformation or velocity. Many challenges of interfacing between scales have been overcome. Multiple models at different scales have been used to study the same system or calculate the same property (e.g., channel conductance). Accurate modeling of biochemical processes under in vivo conditions and the bridging of molecular and subcellular scales will likely soon become reality. PMID:24492203

  6. Canadian Language Benchmarks 2000: Theoretical Framework.

    ERIC Educational Resources Information Center

    Pawlikowska-Smith, Grazyna

    This document provides indepth study and support of the "Canadian Language Benchmarks 2000" (CLB 2000). In order to make the CLB 2000 usable, the competencies and standards were considerably compressed and simplified, and much of the indepth discussion of language ability or proficiency was omitted, at publication. This document includes: (1)…

  7. Interpersonal Relations: A Choice-Theoretic Framework.

    ERIC Educational Resources Information Center

    Couvillion, L. Michael; Eckstein, Daniel G.

    The microeconomic theory relating to utility and cost is applied to the "risk," and the possible "payoff" relative to relationships with others. A good measure of utility is the need or want-satisfying power of an alternative. For the analysis of interpersonal relationships, the needs delineated by Maslow (i.e. food, shelter, belongingness, love,…

  8. Theoretical Frameworks for Studying Female Marriage Migrants

    ERIC Educational Resources Information Center

    Merali, Noorfarah

    2008-01-01

    Transnational marriages account for a significant proportion of family-based immigration to North America. An increasing number of immigrant men are choosing to marry women from their countries of origin, and an increasing number of nonimmigrant men are choosing to marry women from other countries. Existing studies on the experiences of foreign…

  9. Interpersonal Relations: A Choice-Theoretic Framework.

    ERIC Educational Resources Information Center

    Couvillion, L. Michael; Eckstein, Daniel G.

    The microeconomic theory relating to utility and cost is applied to the "risk," and the possible "payoff" relative to relationships with others. A good measure of utility is the need or want-satisfying power of an alternative. For the analysis of interpersonal relationships, the needs delineated by Maslow (i.e. food, shelter, belongingness, love,…

  10. Assessing Algebraic Solving Ability: A Theoretical Framework

    ERIC Educational Resources Information Center

    Lian, Lim Hooi; Yew, Wun Thiam

    2012-01-01

    Algebraic solving ability had been discussed by many educators and researchers. There exists no definite definition for algebraic solving ability as it can be viewed from different perspectives. In this paper, the nature of algebraic solving ability in terms of algebraic processes that demonstrate the ability in solving algebraic problem is…

  11. Theoretical geodesy

    NASA Astrophysics Data System (ADS)

    Borkowski, Andrzej; Kosek, Wiesław

    2015-12-01

    The paper presents a summary of research activities concerning theoretical geodesy performed in Poland in the period of 2011-2014. It contains the results of research on new methods of the parameter estimation, a study on robustness properties of the M-estimation, control network and deformation analysis, and geodetic time series analysis. The main achievements in the geodetic parameter estimation involve a new model of the M-estimation with probabilistic models of geodetic observations, a new Shift-Msplit estimation, which allows to estimate a vector of parameter differences and the Shift-Msplit(+) that is a generalisation of Shift-Msplit estimation if the design matrix A of a functional model has not a full column rank. The new algorithms of the coordinates conversion between the Cartesian and geodetic coordinates, both on the rotational and triaxial ellipsoid can be mentioned as a highlights of the research of the last four years. New parameter estimation models developed have been adopted and successfully applied to the control network and deformation analysis. New algorithms based on the wavelet, Fourier and Hilbert transforms were applied to find time-frequency characteristics of geodetic and geophysical time series as well as time-frequency relations between them. Statistical properties of these time series are also presented using different statistical tests as well as 2nd, 3rd and 4th moments about the mean. The new forecasts methods are presented which enable prediction of the considered time series in different frequency bands.

  12. The Co-Emergence of Machine Techniques, Paper-and-Pencil Techniques, and Theoretical Reflection: A Study of CAS Use in Secondary School Algebra

    ERIC Educational Resources Information Center

    Kieran, Carolyn; Drijvers, Paul

    2006-01-01

    This paper addresses the dialectical relation between theoretical thinking and technique, as they co-emerge in a combined computer algebra (CAS) and paper-and-pencil environment. The theoretical framework in this ongoing study consists of the instrumental approach to tool use and an adaptation of Chevallard's anthropological theory. The main aim…

  13. Framework for Supporting Web-Based Collaborative Applications

    NASA Astrophysics Data System (ADS)

    Dai, Wei

    The article proposes an intelligent framework for supporting Web-based applications. The framework focuses on innovative use of existing resources and technologies in the form of services and takes the leverage of theoretical foundation of services science and the research from services computing. The main focus of the framework is to deliver benefits to users with various roles such as service requesters, service providers, and business owners to maximize their productivity when engaging with each other via the Web. The article opens up with research motivations and questions, analyses the existing state of research in the field, and describes the approach in implementing the proposed framework. Finally, an e-health application is discussed to evaluate the effectiveness of the framework where participants such as general practitioners (GPs), patients, and health-care workers collaborate via the Web.

  14. Framework for the Future

    ERIC Educational Resources Information Center

    Schuller, Tom

    2008-01-01

    The main goal of the Inquiry into the Future for Lifelong Learning is to provide a "strategic framework" for the future. In this article, the author considers the key components that will make up the framework. These are: (1) a statement of vision and values; (2) a stock-take of the current position; (3) an "investment rationale"; (4) some…

  15. Theoretical Issues

    SciTech Connect

    Marc Vanderhaeghen

    2007-04-01

    The theoretical issues in the interpretation of the precision measurements of the nucleon-to-Delta transition by means of electromagnetic probes are highlighted. The results of these measurements are confronted with the state-of-the-art calculations based on chiral effective-field theories (EFT), lattice QCD, large-Nc relations, perturbative QCD, and QCD-inspired models. The link of the nucleon-to-Delta form factors to generalized parton distributions (GPDs) is also discussed.

  16. Institute for Theoretical Physics

    SciTech Connect

    Giddings, S.B.; Ooguri, H.; Peet, A.W.; Schwarz, J.H.

    1998-06-01

    String theory is the only serious candidate for a unified description of all known fundamental particles and interactions, including gravity, in a single theoretical framework. Over the past two years, activity in this subject has grown rapidly, thanks to dramatic advances in understanding the dynamics of supersymmetric field theories and string theories. The cornerstone of these new developments is the discovery of duality which relates apparently different string theories and transforms difficult strongly coupled problems of one theory into weakly coupled problems of another theory.

  17. Theoretical geology

    NASA Astrophysics Data System (ADS)

    Mikeš, Daniel

    2010-05-01

    Theoretical geology Present day geology is mostly empirical of nature. I claim that geology is by nature complex and that the empirical approach is bound to fail. Let's consider the input to be the set of ambient conditions and the output to be the sedimentary rock record. I claim that the output can only be deduced from the input if the relation from input to output be known. The fundamental question is therefore the following: Can one predict the output from the input or can one predict the behaviour of a sedimentary system? If one can, than the empirical/deductive method has changes, if one can't than that method is bound to fail. The fundamental problem to solve is therefore the following: How to predict the behaviour of a sedimentary system? It is interesting to observe that this question is never asked and many a study is conducted by the empirical/deductive method; it seems that the empirical method has been accepted as being appropriate without question. It is, however, easy to argument that a sedimentary system is by nature complex and that several input parameters vary at the same time and that they can create similar output in the rock record. It follows trivially from these first principles that in such a case the deductive solution cannot be unique. At the same time several geological methods depart precisely from the assumption, that one particular variable is the dictator/driver and that the others are constant, even though the data do not support such an assumption. The method of "sequence stratigraphy" is a typical example of such a dogma. It can be easily argued that all the interpretation resulting from a method that is built on uncertain or wrong assumptions is erroneous. Still, this method has survived for many years, nonwithstanding all the critics it has received. This is just one example of the present day geological world and is not unique. Even the alternative methods criticising sequence stratigraphy actually depart from the same erroneous assumptions and do not solve the very fundamental issue that lies at the base of the problem. This problem is straighforward and obvious: a sedimentary system is inherently four-dimensional (3 spatial dimensions + 1 temporal dimension). Any method using an inferior number or dimensions is bound to fail to describe the evolution of a sedimentary system. It is indicative of the present day geological world that such fundamental issues be overlooked. The only reason for which one can appoint the socalled "rationality" in todays society. Simple "common sense" leads us to the conclusion that in this case the empirical method is bound to fail and the only method that can solve the problem is the theoretical approach. Reasoning that is completely trivial for the traditional exact sciences like physics and mathematics and applied sciences like engineering. However, not for geology, a science that was traditionally descriptive and jumped to empirical science, skipping the stage of theoretical science. I argue that the gap of theoretical geology is left open and needs to be filled. Every discipline in geology lacks a theoretical base. This base can only be filled by the theoretical/inductive approach and can impossibly be filled by the empirical/deductive approach. Once a critical mass of geologists realises this flaw in todays geology, we can start solving the fundamental problems in geology.

  18. Decision support models for solid waste management: Review and game-theoretic approaches

    SciTech Connect

    Karmperis, Athanasios C.; Aravossis, Konstantinos; Tatsiopoulos, Ilias P.; Sotirchos, Anastasios

    2013-05-15

    Highlights: ► The mainly used decision support frameworks for solid waste management are reviewed. ► The LCA, CBA and MCDM models are presented and their strengths, weaknesses, similarities and possible combinations are analyzed. ► The game-theoretic approach in a solid waste management context is presented. ► The waste management bargaining game is introduced as a specific decision support framework. ► Cooperative and non-cooperative game-theoretic approaches to decision support for solid waste management are discussed. - Abstract: This paper surveys decision support models that are commonly used in the solid waste management area. Most models are mainly developed within three decision support frameworks, which are the life-cycle assessment, the cost–benefit analysis and the multi-criteria decision-making. These frameworks are reviewed and their strengths and weaknesses as well as their critical issues are analyzed, while their possible combinations and extensions are also discussed. Furthermore, the paper presents how cooperative and non-cooperative game-theoretic approaches can be used for the purpose of modeling and analyzing decision-making in situations with multiple stakeholders. Specifically, since a waste management model is sustainable when considering not only environmental and economic but also social aspects, the waste management bargaining game is introduced as a specific decision support framework in which future models can be developed.

  19. MVC Framework

    Energy Science and Technology Software Center (ESTSC)

    2008-06-03

    Provides a reusable model-view-controller application programming interface (API) for use in the rapid development of graphical user interface applications in the .NET 2.0 framework. This includes a mechanism for adding new data stores, data sources, data analyses, and visualizations in the form of plugins.] The MVC Framework is implemented in C# as a .NET 2.0 framework that can then be built against when developing applications. The infrasturcture allows for presenting application specific views (visualizations) tomore » the user to interact with. Based on the interactions the suer makes with a view, requests are generated which in turn are handled by the central controller facility. The controller handles the request in an application specific manner by routing the request to appropriate data stores, data accessors or data analyzers. Retrieved or processed data is published to subscribed components for further processing or for presentation to the user.« less

  20. MVC Framework

    SciTech Connect

    2008-06-03

    Provides a reusable model-view-controller application programming interface (API) for use in the rapid development of graphical user interface applications in the .NET 2.0 framework. This includes a mechanism for adding new data stores, data sources, data analyses, and visualizations in the form of plugins.] The MVC Framework is implemented in C# as a .NET 2.0 framework that can then be built against when developing applications. The infrasturcture allows for presenting application specific views (visualizations) to the user to interact with. Based on the interactions the suer makes with a view, requests are generated which in turn are handled by the central controller facility. The controller handles the request in an application specific manner by routing the request to appropriate data stores, data accessors or data analyzers. Retrieved or processed data is published to subscribed components for further processing or for presentation to the user.

  1. Scaling Up Decision Theoretic Planning to Planetary Rover Problems

    NASA Technical Reports Server (NTRS)

    Meuleau, Nicolas; Dearden, Richard; Washington, Rich

    2004-01-01

    Because of communication limits, planetary rovers must operate autonomously during consequent durations. The ability to plan under uncertainty is one of the main components of autonomy. Previous approaches to planning under uncertainty in NASA applications are not able to address the challenges of future missions, because of several apparent limits. On another side, decision theory provides a solid principle framework for reasoning about uncertainty and rewards. Unfortunately, there are several obstacles to a direct application of decision-theoretic techniques to the rover domain. This paper focuses on the issues of structure and concurrency, and continuous state variables. We describes two techniques currently under development that address specifically these issues and allow scaling-up decision theoretic solution techniques to planetary rover planning problems involving a small number of goals.

  2. FRAMEWORK DOCUMENTS

    EPA Science Inventory

    Defn: Framework Document - A peer-reviewed document stating overarching principles and practices to be followed.

    Feminist Frameworks for Researching Mathematics

    ERIC Educational Resources Information Center

    Kaiser, Gabriele

    2003-01-01

    The discussion on gender has been broadened in the last few years, with the demand for equity now as a central goal of the debate. In this context two main theoretical approaches, which are nowadays significantly influencing the discussion on gender in mathematics education, have been developed and will be introduced. Embedded in the theoretical…

  3. Space Transportation Main Engine

    NASA Astrophysics Data System (ADS)

    Monk, Jan C.

    1992-07-01

    The topics are presented in viewgraph form and include the following: Space Transportation Main Engine (STME) definition, design philosophy, robust design, maximum design condition, casting vs. machined and welded forgings, operability considerations, high reliability design philosophy, engine reliability enhancement, low cost design philosophy, engine systems requirements, STME schematic, fuel turbopump, liquid oxygen turbopump, main injector, and gas generator. The major engine components of the STME and the Space Shuttle Main Engine are compared.

  4. The Maine Event

    ERIC Educational Resources Information Center

    McHale, Tom

    2007-01-01

    In this article, the author describes the successful laptop program employed at Mt. Abram High School in Strong, Maine. Through the Maine Learning Technology Initiative, the school has issued laptops to all 36,000 teachers and students in grades 7-8. This program has helped level the playing field for a student population that is 50 percent to 55…

  5. The Maine Event

    ERIC Educational Resources Information Center

    McHale, Tom

    2007-01-01

    In this article, the author describes the successful laptop program employed at Mt. Abram High School in Strong, Maine. Through the Maine Learning Technology Initiative, the school has issued laptops to all 36,000 teachers and students in grades 7-8. This program has helped level the playing field for a student population that is 50 percent to 55…

  6. MAINE MARINE WORM HABITAT

    EPA Science Inventory

    WORM provides a generalized representation at 1:24,000 scale of commercially harvested marine worm habitat in Maine, based on Maine Department of Marine Resources data from 1970's. Original maps were created by MDMR and published by USF&WS as part of the ""&quo...

  7. An Evaluation Use Framework and Empirical Assessment

    ERIC Educational Resources Information Center

    Peck, Laura R.; Gorzalski, Lindsey M.

    2009-01-01

    Background: Research on evaluation use focuses on putting evaluation recommendations into practice. Prior theoretical research proposes varied frameworks for understanding the use (or lack) of program evaluation results. Purpose: Our purpose is to create and test a single, integrated framework for understanding evaluation use. This article relies…

  8. MAINE WEIRS 1990

    EPA Science Inventory

    WEIR90 shows point locations of herring weirs in Maine based on 1990 overflight by MDMR Marine Patrol, mapped at an approximate scale of 1:100,000. Data were screen digitized from paper maps used during the overflight.

  9. Seven Basic Steps to Solving Ethical Dilemmas in Special Education: A Decision-Making Framework

    ERIC Educational Resources Information Center

    Stockall, Nancy; Dennis, Lindsay R.

    2015-01-01

    This article presents a seven-step framework for decision making to solve ethical issues in special education. The authors developed the framework from the existing literature and theoretical frameworks of justice, critique, care, and professionalism. The authors briefly discuss each theoretical framework and then describe the decision-making…

  10. Seven Basic Steps to Solving Ethical Dilemmas in Special Education: A Decision-Making Framework

    ERIC Educational Resources Information Center

    Stockall, Nancy; Dennis, Lindsay R.

    2015-01-01

    This article presents a seven-step framework for decision making to solve ethical issues in special education. The authors developed the framework from the existing literature and theoretical frameworks of justice, critique, care, and professionalism. The authors briefly discuss each theoretical framework and then describe the decision-making…

  11. Main features of meiosis

    SciTech Connect

    1993-12-31

    Chapter 17, outlines the main features of meiosis, beginning with its significance and proceeding through the meiotic stages. Meiosis is the most important modification of mitosis because it is the reduction division that gives rise to the haploid generation in the life cycle. 17 refs., 6 figs.

  12. MAINE SCHOOLS AND LIBRARIES

    EPA Science Inventory

    SCHLIB shows point locations of libraries and educational institutions in Maine at 1:24,000 scale. Colleges, universities, technical colleges, high schools, middle schools, elementary schools, kindergarten/sub-primary and other special schools are included. The data was developed...

  13. Indians of Maine.

    ERIC Educational Resources Information Center

    Maine State Dept. of Health and Welfare, Augusta.

    The relationships between the Penobscot and Passamaquoddy Indian Tribes and the State of Maine began in the 1820's. Treaties have left the Penobscot tribe with ownership of 146 islands in the Penobscot River while the Passamaquoddy tribe lives on land owned by the State. Both tribes presently have trust funds derived from the sale of land, and use…

  14. Main Parachute Test

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Shown is the testing of the Main Parachute for the Ares/CLV first stage in support of the Ares/Constellation program at the Yuma Proving Ground, Arizona. This image is extracted from high definition video and is the highest resolution available.

  15. Snow Falls - Maine

    USGS Multimedia Gallery

    As the Little Androscoggin River flows through western Maine it eventually reaches Snow Falls, a 25 ft cascading waterfall in the town of West Paris.  This photo was taken during a high flow event at the falls. The USGS monitors the Little Androscoggin River upstream of the falls at station 01...

  16. Ladybugs of Maine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Color images are presented for the 57 species of Coccinellidae, commonly known as ladybugs, that are documented from Maine. Images are displayed in taxonomic order. Information on each species includes its genus-species name, length, and an actual-size silhouette beside a grid matched to the scale...

  17. V&V framework

    SciTech Connect

    Hills, Richard G.; Maniaci, David Charles; Naughton, Jonathan W.

    2015-09-01

    A Verification and Validation (V&V) framework is presented for the development and execution of coordinated modeling and experimental program s to assess the predictive capability of computational models of complex systems through focused, well structured, and formal processes.The elements of the framework are based on established V&V methodology developed by various organizations including the Department of Energy, National Aeronautics and Space Administration, the American Institute of Aeronautics and Astronautics, and the American Society of Mechanical Engineers. Four main topics are addressed: 1) Program planning based on expert elicitation of the modeling physics requirements, 2) experimental design for model assessment, 3) uncertainty quantification for experimental observations and computational model simulations, and 4) assessment of the model predictive capability. The audience for this document includes program planners, modelers, experimentalist, V &V specialist, and customers of the modeling results.

  18. Jupiter's Main Ring

    NASA Technical Reports Server (NTRS)

    1997-01-01

    A mosaic of four images taken through the clear filter (610 nanometers) of the solid state imaging (CCD) system aboard NASA's Galileo spacecraft on November 8, 1996, at a resolution of approximately 46 kilometers (km) per picture element (pixel) along the rings; however, because the spacecraft was only about 0.5 degrees above the ring plane, the image is highly foreshortened in the vertical direction. The images were obtained when Galileo was in Jupiter's shadow peering back toward the Sun; the ring was approximately 2,300,000 kilometers (km) away. The arc on the far right of the image is produced by sunlight scattered by small particles comprising Jupiter's upper atmospheric haze. The ring also efficiently scatters light, indicating that much of its brightness is due to particles that are microns or less in diameter. Such small particles are believed to have human-scale lifetimes, i.e., very brief compared to the solar system's age.

    Jupiter's ring system is composed of three parts -- a flat main ring, a lenticular halo interior to the main ring, and the gossamer ring, which lies exterior to the main ring. The near and far arms of Jupiter's main ring extend horizontally across the mosaic, joining together at the ring's ansa, on the far left side of the figure. The near arm of the ring appears to be abruptly truncated close to the planet, at the point where it passes into Jupiter's shadow. Some radial structure is barely visible across the ring's ansa. A faint mist of particles can be seen above and below the main rings; this vertically extended 'halo' is unusual in planetary rings, and is probably caused by electromagnetic forces pushing the smallest grains out of the ring plane. Because of shadowing, the halo is not visible close to Jupiter in the lower right part of the mosaic.

    Jupiter's main ring is a thin strand of material encircling the planet. The diffuse innermost boundary begins at approximately 123,000 km. The main ring's outer radius is found to be at 128,940 +/-50 km, slightly less than the Voyager value of 129,130 +/-100 km, but very close to the orbit of the satellite Adrastea (128,980 km). The main ring exhibits a marked drop in brightness at 127,849 +/-50 km, lying almost atop the orbit of the Jovian moon Metis at 127,978 km. Satellites seem to affect the structure of even tenuous rings like that found at Jupiter.

    The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.

    This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at: http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at: http:/ /www.jpl.nasa.gov/galileo/sepo.

  19. COBRA Main Engine Project

    NASA Technical Reports Server (NTRS)

    Snoddy, Jim; Sides, Steve; Lyles, Garry M. (Technical Monitor)

    2002-01-01

    The COBRA (CO-Optimized Booster for Reusable Applications) project include the following: 1. COBRA main engine project team. 2. COBRA and RLX cycles selected. 3. COBRA proto-type engine approach enables mission success. 4. COBRA provides quick, low cost demo of cycle and technologies. 5. COBRA cycle I risk reduction supports. 6. Achieving engine safety. 6. RLX cycle I risk reduction supports. 7. Flight qualification. 9. Life extension engine testing.

    1. Maine coast winds

      SciTech Connect

      Avery, Richard

      2000-01-28

      The Maine Coast Winds Project was proposed for four possible turbine locations. Significant progress has been made at the prime location, with a lease-power purchase contract for ten years for the installation of turbine equipment having been obtained. Most of the site planning and permitting have been completed. It is expect that the turbine will be installed in early May. The other three locations are less suitable for the project, and new locations are being considered.

    2. Decades of Theoretical Work on Protonated Hydrates

      NASA Astrophysics Data System (ADS)

      Kochanski, E.; Kelterbaum, R.; Klein, S.; Rohmer, M. M.; Rahmouni, A.

      Theoretical studies on protonated hydrates (PH) are illustrative of the progress realized in theoretical chemistry over several decades. The evolution of such studies is presented. The main methods used (quantum chemistry, Monte Carlo or Molecular Dynamics calculations...) and the problems encountered are briefly recalled. Some of the results obtained are commented.

    3. Disseminating research findings: what should researchers do? A systematic scoping review of conceptual frameworks

      PubMed Central

      2010-01-01

      Background Addressing deficiencies in the dissemination and transfer of research-based knowledge into routine clinical practice is high on the policy agenda both in the UK and internationally. However, there is lack of clarity between funding agencies as to what represents dissemination. Moreover, the expectations and guidance provided to researchers vary from one agency to another. Against this background, we performed a systematic scoping to identify and describe any conceptual/organising frameworks that could be used by researchers to guide their dissemination activity. Methods We searched twelve electronic databases (including MEDLINE, EMBASE, CINAHL, and PsycINFO), the reference lists of included studies and of individual funding agency websites to identify potential studies for inclusion. To be included, papers had to present an explicit framework or plan either designed for use by researchers or that could be used to guide dissemination activity. Papers which mentioned dissemination (but did not provide any detail) in the context of a wider knowledge translation framework, were excluded. References were screened independently by at least two reviewers; disagreements were resolved by discussion. For each included paper, the source, the date of publication, a description of the main elements of the framework, and whether there was any implicit/explicit reference to theory were extracted. A narrative synthesis was undertaken. Results Thirty-three frameworks met our inclusion criteria, 20 of which were designed to be used by researchers to guide their dissemination activities. Twenty-eight included frameworks were underpinned at least in part by one or more of three different theoretical approaches, namely persuasive communication, diffusion of innovations theory, and social marketing. Conclusions There are currently a number of theoretically-informed frameworks available to researchers that can be used to help guide their dissemination planning and activity. Given the current emphasis on enhancing the uptake of knowledge about the effects of interventions into routine practice, funders could consider encouraging researchers to adopt a theoretically-informed approach to their research dissemination. PMID:21092164

    4. Changing Mental Models of the IT Professions: A Theoretical Framework

      ERIC Educational Resources Information Center

      Agosto, Denise E.; Gasson, Susan; Atwood, Michael

      2008-01-01

      It is widely recognized that the current and projected shortage of adequately-educated IT professionals could be greatly reduced if more female and minority students would major in IT disciplines, yet the dramatic under-representation of these populations appears to be worsening. This under-representation is reflected in Drexel University's…

    5. Understanding Family Role Reallocation Following a Death: A Theoretical Framework.

      ERIC Educational Resources Information Center

      Vess, James; And Others

      1986-01-01

      Examines factors which contribute to reactions and recovery patterns in families in which a parent has died. Discusses influence of stage of family life cycle, roles of deceased, previous patterns of role allocation, and type of death. Compares reallocation of family roles by "person oriented" and "position oriented" families. (Author/NRB)

    6. Changing Mental Models of the IT Professions: A Theoretical Framework

      ERIC Educational Resources Information Center

      Agosto, Denise E.; Gasson, Susan; Atwood, Michael

      2008-01-01

      It is widely recognized that the current and projected shortage of adequately-educated IT professionals could be greatly reduced if more female and minority students would major in IT disciplines, yet the dramatic under-representation of these populations appears to be worsening. This under-representation is reflected in Drexel University's…

    7. Research Leadership in Writing for Publication: A Theoretical Framework

      ERIC Educational Resources Information Center

      Murray, Rowena; Steckley, Laura; MacLeod, Iain

      2012-01-01

      Academics experience difficulty in managing competing tasks, particularly in relation to writing for publication. In a study conducted on a writing retreat, analysis of data obtained from academic writers revealed that facilitative leadership provided at a writing retreat was central to managing task complexity and writing-related anxiety. The…

    8. Understanding New Media Literacy: An Explorative Theoretical Framework

      ERIC Educational Resources Information Center

      Lin, Tzu-Bin; Li, Jen-Yi; Deng, Feng; Lee, Ling

      2013-01-01

      With the advent of new media technologies, the role of media in a society has been changed that leads researchers to re-construct the meaning of literacy from classic literacy to new media literacy. There have been continuing efforts to understand new media and promote the importance of becoming new media literate among researchers, educators,…

    9. Design theoretic analysis of three system modeling frameworks.

      SciTech Connect

      McDonald, Michael James

      2007-05-01

      This paper analyzes three simulation architectures from the context of modeling scalability to address System of System (SoS) and Complex System problems. The paper first provides an overview of the SoS problem domain and reviews past work in analyzing model and general system complexity issues. It then identifies and explores the issues of vertical and horizontal integration as well as coupling and hierarchical decomposition as the system characteristics and metrics against which the tools are evaluated. In addition, it applies Nam Suh's Axiomatic Design theory as a construct for understanding coupling and its relationship to system feasibility. Next it describes the application of MATLAB, Swarm, and Umbra (three modeling and simulation approaches) to modeling swarms of Unmanned Flying Vehicle (UAV) agents in relation to the chosen characteristics and metrics. Finally, it draws general conclusions for analyzing model architectures that go beyond those analyzed. In particular, it identifies decomposition along phenomena of interaction and modular system composition as enabling features for modeling large heterogeneous complex systems.

    10. Integrated Information in Discrete Dynamical Systems: Motivation and Theoretical Framework

      PubMed Central

      Balduzzi, David; Tononi, Giulio

      2008-01-01

      This paper introduces a time- and state-dependent measure of integrated information, ?, which captures the repertoire of causal states available to a system as a whole. Specifically, ? quantifies how much information is generated (uncertainty is reduced) when a system enters a particular state through causal interactions among its elements, above and beyond the information generated independently by its parts. Such mathematical characterization is motivated by the observation that integrated information captures two key phenomenological properties of consciousness: (i) there is a large repertoire of conscious experiences so that, when one particular experience occurs, it generates a large amount of information by ruling out all the others; and (ii) this information is integrated, in that each experience appears as a whole that cannot be decomposed into independent parts. This paper extends previous work on stationary systems and applies integrated information to discrete networks as a function of their dynamics and causal architecture. An analysis of basic examples indicates the following: (i) ? varies depending on the state entered by a network, being higher if active and inactive elements are balanced and lower if the network is inactive or hyperactive. (ii) ? varies for systems with identical or similar surface dynamics depending on the underlying causal architecture, being low for systems that merely copy or replay activity states. (iii) ? varies as a function of network architecture. High ? values can be obtained by architectures that conjoin functional specialization with functional integration. Strictly modular and homogeneous systems cannot generate high ? because the former lack integration, whereas the latter lack information. Feedforward and lattice architectures are capable of generating high ? but are inefficient. (iv) In Hopfield networks, ? is low for attractor states and neutral states, but increases if the networks are optimized to achieve tension between local and global interactions. These basic examples appear to match well against neurobiological evidence concerning the neural substrates of consciousness. More generally, ? appears to be a useful metric to characterize the capacity of any physical system to integrate information. PMID:18551165

    11. [Demographic population forecasts: theoretical framework, assumptions, and prediction uncertainty].

      PubMed

      Steinberg, J; Doblhammer-Reiter, G

      2010-05-01

      Population forecasts are not only highly demanded by scientists, politicians, and economists, but also by the general public. Thereby the wish of the users for only one forecast runs contrary to the uncertainty of the future developments of the population. In the past, but also today, population forecasts were and are predominantly accomplished by applying a deterministic approach: the Cohort Component Method. To counteract the uncertainty of future trends in the demographic processes in fertility, mortality, and migration, different scenarios are applied. Many studies have analyzed ex post the accuracy of past population projections. They show that, in addition to other factors, the time horizon and the level of regional aggregation influence the accuracy of the forecast outcomes. In particular, errors in the assumptions about future trends in fertility, mortality, and migration determine the accuracy of the forecasts. In many cases, these assumptions under- or overestimated the real trends. Progress in the question on uncertainty was made in recent years using a new approach: probabilistic forecasts which include probabilities of future trends in demographic processes. PMID:20437023

    12. A Theoretical Framework for Understanding Those Fabulous (?) Sixties.

      ERIC Educational Resources Information Center

      Kinsella, Timothy

      1995-01-01

      Describes instructional strategies and content for a course titled "Those Fabulous (?) Sixties." Discusses the course structure outlining four paradigms of social science research and action. Maintains that the course helps students know more about themselves, their values, and their relationships to society. (CFR)

    13. Assessment of Student Outcomes Using a Theoretical Framework.

      ERIC Educational Resources Information Center

      Levins, Lesley

      1997-01-01

      Examines the scientific concept of evaporation. Attempts to show how students develop their understanding through the levels of the Structure of the Observed Learning Outcome (SOLO) taxonomy. Shows how designing learning experiences to suit the learners' developmental stages in understanding a concept is paramount to the overall growth of the…

    14. The growth of business firms: Theoretical framework and empirical evidence

      PubMed Central

      Fu, Dongfeng; Pammolli, Fabio; Buldyrev, S. V.; Riccaboni, Massimo; Matia, Kaushik; Yamasaki, Kazuko; Stanley, H. Eugene

      2005-01-01

      We introduce a model of proportional growth to explain the distribution Pg(g) of business-firm growth rates. The model predicts that Pg(g) is exponential in the central part and depicts an asymptotic power-law behavior in the tails with an exponent ? = 3. Because of data limitations, previous studies in this field have been focusing exclusively on the Laplace shape of the body of the distribution. In this article, we test the model at different levels of aggregation in the economy, from products to firms to countries, and we find that the predictions of the model agree with empirical growth distributions and size-variance relationships. PMID:16365284

    15. Low Frequency Instabilities in Confined Plasmas: Concepts and Theoretical Framework

      SciTech Connect

      Rogister, Andre L

      2004-03-15

      Most experts consider that anomalous energy and particle transport in fusion devices are due to low frequency waves whose free energy sources are the equilibrium gradients and the associated drifts across the confining magnetic field (drift waves)

    16. Understanding Educational Transfer: Theoretical Perspectives and Conceptual Frameworks

      ERIC Educational Resources Information Center

      Perry, Laura B.; Tor, Geok-hwa

      2008-01-01

      Educational transfer is an important and growing body of literature in the field of comparative education. Work from the last decade has focused on the stages of the borrowing cycle, and the context, causes and rationales for education borrowing. This recent work has contributed to earlier research on the role of multilateral organizations in…

    17. Understanding Educational Transfer: Theoretical Perspectives and Conceptual Frameworks

      ERIC Educational Resources Information Center

      Perry, Laura B.; Tor, Geok-hwa

      2008-01-01

      Educational transfer is an important and growing body of literature in the field of comparative education. Work from the last decade has focused on the stages of the borrowing cycle, and the context, causes and rationales for education borrowing. This recent work has contributed to earlier research on the role of multilateral organizations in…

    18. Primary Teachers' Attitudes toward Science: A New Theoretical Framework

      ERIC Educational Resources Information Center

      van Aalderen-Smeets, Sandra I.; Walma van der Molen, Juliette H.; Asma, Lieke J. F.

      2012-01-01

      Attention to the attitudes of preservice and inservice primary teachers toward science is of fundamental importance to research on primary science education. However, progress in this field of research has been slow due to the poor definition and conceptualization of the construct of primary teachers' attitude toward science. This poor theoretical…

    19. A Theoretical Framework for RN to BSN Education.

      ERIC Educational Resources Information Center

      Eckhardt, Jo Anne; Anderson, Debra Matthias; Campbell, Susan Ellen; Clarke, Suzanne E.; Pavlish, Carol L.

      2002-01-01

      Associate and baccalaureate degree nursing faculty collaborated in development of bridging courses for a registered nurse to bachelor of science in nursing program. Learning experiences were planned around five reflective practice processes: reflective conversation, fluid inquiry, conceptualization, cognitive frame analysis, and artful design. (SK)

    20. Exploring theoretical frameworks for the analysis of fertility fluctuations.

      PubMed

      Micheli, G A

      1988-05-01

      The Easterlin theory, popular during the 1970s, explained population fluctuations in terms of maximization of choice, based on the evaluation of previously acquired information. Fluctuations in procreational patterns were seen as responses to conflict between 2 consecutive generations in which the propensity to procreate is inversely related to cohort size. However, the number of demographic trends not directly explainable by the hypothesis imply that either the model must be extended over a longer time frame or that there has been a drastic change of regime, i.e., a basic change in popular attitudes which determine decision making behavior. 4 strategic principles underlie reproductive decisions: primary adaptation, economic utility, norm internalization, and identity reinforcement. The decision-making process is determined by the relative importance of these 4 principles. Primary adaptation implies inertia, i.e., nondecision. Economic utility implies the use of rational choice to maximize economic gain. Norm internalization implies conforming to the behavior of one's sociocultural peers as if it were one's own choice. Identity reinforcement implies that one decides to reproduce because procreation is a way of extending one's identity forward in time. The 2 active decision-making attitudes, economic rationality and identity reinforcement, are strategically both antagonistic and complementary. This polarity of behavior lends itself to analysis in terms of the predator-prey model, in which population is seen as the predator and resources as the prey. However, in applying the model, one must keep in mind that the real demographic picture is not static and that it is subject to deformation by external forces. PMID:12158954

    1. Understanding New Media Literacy: An Explorative Theoretical Framework

      ERIC Educational Resources Information Center

      Lin, Tzu-Bin; Li, Jen-Yi; Deng, Feng; Lee, Ling

      2013-01-01

      With the advent of new media technologies, the role of media in a society has been changed that leads researchers to re-construct the meaning of literacy from classic literacy to new media literacy. There have been continuing efforts to understand new media and promote the importance of becoming new media literate among researchers, educators,…

    2. Emergent Writing in Preschoolers: Preliminary Evidence for a Theoretical Framework

      ERIC Educational Resources Information Center

      Puranik, Cynthia S.; Lonigan, Christopher J.

      2014-01-01

      Researchers and educators use the term "emergent literacy" to refer to a broad set of skills and attitudes that serve as foundational skills for acquiring success in later reading and writing; however, models of emergent literacy have generally focused on reading and reading-related behaviors. Hence, the primary aim of this study was to…

    3. Macro and Micro Features of Informal Meetings: A Theoretical Framework.

      ERIC Educational Resources Information Center

      Mangrum, Faye Gothard

      This paper presents a comprehensive picture of informal problem solving (IPS) meetings where gatherings of workers meet around computer screens, at their desks, in doorways, and in halls to accomplish multiple work-related tasks. It attempts to uncover interactional details of informal meetings by providing a micro-analytic model of informal…

    4. Nonrelativistic Holography — a Group-Theoretical Perspective

      NASA Astrophysics Data System (ADS)

      Dobrev, V. K.

      2014-01-01

      We give a review of some group-theoretical results related to nonrelativistic holography. Our main playgrounds are the Schrödinger equation and the Schrödinger algebra. We first recall the interpretation of nonrelativistic holography as equivalence between representations of the Schrödinger algebra describing bulk fields and boundary fields. One important result is the explicit construction of the boundary-to-bulk operators in the framework of representation theory, and that these operators and the bulk-to-boundary operators are intertwining operators. Further, we recall the fact that there is a hierarchy of equations on the boundary, invariant with respect to Schrödinger algebra. We also review the explicit construction of an analogous hierarchy of invariant equations in the bulk, and that the two hierarchies are equivalent via the bulk-to-boundary intertwining operators. The derivation of these hierarchies uses a mechanism introduced first for semisimple Lie groups and adapted to the nonsemisimple Schrödinger algebra. These require development of the representation theory of the Schrödinger algebra which is reviewed in some detail. We also recall the q-deformation of the Schrödinger algebra. Finally, the realization of the Schrödinger algebra via difference operators is reviewed.

    5. Aquarius main structure configuration

      NASA Astrophysics Data System (ADS)

      Eremenko, A.

      The Aquarius/SAC-D Observatory is a joint US-Argentine mission to map the salinity at the ocean surface. This information is critical to improving our understanding of two major components of Earth's climate system - the water cycle and ocean circulation. By measuring ocean salinity from space, the Aquarius/SAC-D Mission will provide new insights into how the massive natural exchange of freshwater between the ocean, atmosphere and sea ice influences ocean circulation, weather and climate. Aquarius is the primary instrument on the SAC-D spacecraft. It consists of a Passive Microwave Radiometer to detect the surface emission that is used to obtain salinity and an Active Scatterometer to measure the ocean waves that affect the precision of the salinity measurement. The Aquarius Primary Structure houses instrument electronics, feed assemblies, and supports a deployable boom with a 2.5 m Reflector, and provides the structural interface to the SAC-D Spacecraft. The key challenge for the Aquarius main structure configuration is to satisfy the needs of component accommodations, ensuring that the instrument can meet all operational, pointing, environmental, and launch vehicle requirements. This paper describes the evolution of the Aquarius main structure configuration, the challenges of balancing the conflicting requirements, and the major configuration driving decisions and compromises.

    6. Aquarius Main Structure Configuration

      NASA Technical Reports Server (NTRS)

      Eremenko, Alexander

      2012-01-01

      The Aquarius/SAC-D Observatory is a joint US-Argentine mission to map the salinity at the ocean surface. This information is critical to improving our understanding of two major components of Earth's climate system - the water cycle and ocean circulation. By measuring ocean salinity from space, the Aquarius/SAC-D Mission will provide new insights into how the massive natural exchange of freshwater between the ocean, atmosphere and sea ice influences ocean circulation, weather and climate. Aquarius is the primary instrument on the SAC-D spacecraft. It consists of a Passive Microwave Radiometer to detect the surface emission that is used to obtain salinity and an Active Scatterometer to measure the ocean waves that affect the precision of the salinity measurement. The Aquarius Primary Structure houses instrument electronics, feed assemblies, and supports a deployable boom with a 2.5 m Reflector, and provides the structural interface to the SAC-D Spacecraft. The key challenge for the Aquarius main structure configuration is to satisfy the needs of component accommodations, ensuring that the instrument can meet all operational, pointing, environmental, and launch vehicle requirements. This paper describes the evolution of the Aquarius main structure configuration, the challenges of balancing the conflicting requirements, and the major configuration driving decisions and compromises.

    7. Main Oxidizer Valve Design

      NASA Technical Reports Server (NTRS)

      Addona, Brad; Eddleman, David

      2015-01-01

      A developmental Main Oxidizer Valve (MOV) was designed by NASA-MSFC using additive manufacturing processes. The MOV is a pneumatically actuated poppet valve to control the flow of liquid oxygen to an engine's injector. A compression spring is used to return the valve to the closed state when pneumatic pressure is removed from the valve. The valve internal parts are cylindrical in shape, which lends itself to traditional lathe and milling operations. However, the valve body represents a complicated shape and contains the majority of the mass of the valve. Additive manufacturing techniques were used to produce a part that optimized mass and allowed for design features not practical with traditional machining processes.

    8. Rethinking Theoretical Approaches to Stigma

      PubMed Central

      Martin, Jack K; Lang, Annie; Olafsdottir, Sigrun

      2008-01-01

      A resurgence of research and policy efforts on stigma both facilitates and forces a reconsideration of the levels and types of factors that shape reactions to persons with conditions that engender prejudice and discrimination. Focusing on the case of mental illness but drawing from theories and studies of stigma across the social sciences, we propose a framework that brings together theoretical insights from micro, meso and macro level research: Framework Integrating Normative Influences on Stigma (FINIS) starts with Goffman’s notion that understanding stigma requires a language of social relationships, but acknowledges that individuals do not come to social interaction devoid of affect and motivation. Further, all social interactions take place in a context in which organizations, media and larger cultures structure normative expectations which create the possibility of marking “difference”. Labelling theory, social network theory, the limited capacity model of media influence, the social psychology of prejudice and discrimination, and theories of the welfare state all contribute to an understanding of the complex web of expectations shaping stigma. FINIS offers the potential to build a broad-based scientific foundation based on understanding the effects of stigma on the lives of persons with mental illness, the resources devoted to the organizations and families who care for them, and policies and programs designed to combat stigma. We end by discussing the clear implications this framework holds for stigma reduction, even in the face of conflicting results. PMID:18436358

    9. Theoretical study on the bactericidal nature of nanopatterned surfaces.

      PubMed

      Xue, Fudong; Liu, Junjie; Guo, Longfang; Zhang, Lirong; Li, Qianzhong

      2015-11-21

      A natural biomaterial has been discovered with bactericidal activities, which is mainly attributed to its nanopatterned surface structure. The surface of Clanger cicada (Psaltoda claripennis) wings has been identified as a natural bactericidal material, which has lead to the emergence of research on the development of novel antibacterial surfaces. From the interactions between bacterial biofilms and nanopatterned surface structures, a new mechanical model is proposed that investigates the rupture of bacterial cells within the framework of the "stretching" theory. The effect of surface nanoroughness on the survival of bacterial cells is evaluated by determining the stretching ability of their cell walls. The results, calculated using Gram-positive and Gram-negative bacteria as examples, show a correlation between the stretching of the cell wall and the geometric parameters of the surface structures. The theoretical results indicate that for a given cell rigidity, the bactericidal nature of the surface is determined by the geometric parameters of the surface structures. PMID:26343860

    10. Emerging theoretical basis for monitoring the changing states (health) of large marine ecosystems. Technical memo

      SciTech Connect

      Sherman, K.

      1993-09-01

      ;Contents: Workshop Objective; Overview and Background; North Sea Ecosystem Case Study; Great Lakes Basin Ecosystem Case Study; Theoretical Framework; Plankton Recorder Technology; Data Analyses; Summary.

    11. Post-main-sequence planetary system evolution

      PubMed Central

      Veras, Dimitri

      2016-01-01

      The fates of planetary systems provide unassailable insights into their formation and represent rich cross-disciplinary dynamical laboratories. Mounting observations of post-main-sequence planetary systems necessitate a complementary level of theoretical scrutiny. Here, I review the diverse dynamical processes which affect planets, asteroids, comets and pebbles as their parent stars evolve into giant branch, white dwarf and neutron stars. This reference provides a foundation for the interpretation and modelling of currently known systems and upcoming discoveries. PMID:26998326

    12. Post-main-sequence planetary system evolution

      NASA Astrophysics Data System (ADS)

      Veras, Dimitri

      2016-02-01

      The fates of planetary systems provide unassailable insights into their formation and represent rich cross-disciplinary dynamical laboratories. Mounting observations of post-main-sequence planetary systems necessitate a complementary level of theoretical scrutiny. Here, I review the diverse dynamical processes which affect planets, asteroids, comets and pebbles as their parent stars evolve into giant branch, white dwarf and neutron stars. This reference provides a foundation for the interpretation and modelling of currently known systems and upcoming discoveries.

    13. Post-main-sequence planetary system evolution.

      PubMed

      Veras, Dimitri

      2016-02-01

      The fates of planetary systems provide unassailable insights into their formation and represent rich cross-disciplinary dynamical laboratories. Mounting observations of post-main-sequence planetary systems necessitate a complementary level of theoretical scrutiny. Here, I review the diverse dynamical processes which affect planets, asteroids, comets and pebbles as their parent stars evolve into giant branch, white dwarf and neutron stars. This reference provides a foundation for the interpretation and modelling of currently known systems and upcoming discoveries. PMID:26998326

    14. Theoretical Considerations for Understanding Technological Pedagogical Content Knowledge (TPACK)

      ERIC Educational Resources Information Center

      Graham, Charles R.

      2011-01-01

      The technological pedagogical content knowledge (TPACK) framework is increasing in use by educational technology researchers around the world who are interested in issues related to technology integration. Much that is good can be found in the TPACK framework; however considerable theoretical work needs to be done if TPACK research is to cohere…

    15. Main Factors of Teachers' Professional Well-Being

      ERIC Educational Resources Information Center

      Yildirim, Kamil

      2014-01-01

      The purpose of the study was to reveal the main factors of teachers' professional well being. Theoretically constructed model was tested on large scale data belong to 72.190 teachers working at lower secondary level. Theoretical model included teachers' individual, professional and organizational characteristics. Professional well-being…

    16. Proof-Theoretic Semantics for a Natural Language Fragment

      NASA Astrophysics Data System (ADS)

      Francez, Nissim; Dyckhoff, Roy

      We propose a Proof - Theoretic Semantics (PTS) for a (positive) fragment E+0 of Natural Language (NL) (English in this case). The semantics is intended [7] to be incorporated into actual grammars, within the framework of Type - Logical Grammar (TLG) [12]. Thereby, this semantics constitutes an alternative to the traditional model - theoretic semantics (MTS), originating in Montague's seminal work [11], used in TLG.

    17. TrustBuilder2: A Reconfigurable Framework for Trust Negotiation

      NASA Astrophysics Data System (ADS)

      Lee, Adam J.; Winslett, Marianne; Perano, Kenneth J.

      To date, research in trust negotiation has focused mainly on the theoretical aspects of the trust negotiation process, and the development of proof of concept implementations. These theoretical works and proofs of concept have been quite successful from a research perspective, and thus researchers must now begin to address the systems constraints that act as barriers to the deployment of these systems. To this end, we present TrustBuilder2, a fully-configurable and extensible framework for prototyping and evaluating trust negotiation systems. TrustBuilder2 leverages a plug-in based architecture, extensible data type hierarchy, and flexible communication protocol to provide a framework within which numerous trust negotiation protocols and system configurations can be quantitatively analyzed. In this paper, we discuss the design and implementation of TrustBuilder2, study its performance, examine the costs associated with flexible authorization systems, and leverage this knowledge to identify potential topics for future research, as well as a novel method for attacking trust negotiation systems.

    18. The shuttle main engine: A first look

      NASA Technical Reports Server (NTRS)

      Schreur, Barbara

      1996-01-01

      Anyone entering the Space Shuttle Main Engine (SSME) team attends a two week course to become familiar with the design and workings of the engine. This course provides intensive coverage of the individual hardware items and their functions. Some individuals, particularly those involved with software maintenance and development, have felt overwhelmed by this volume of material and their lack of a logical framework in which to place it. To provide this logical framework, it was decided that a brief self-taught introduction to the overall operation of the SSME should be designed. To aid the people or new team members with an interest in the software, this new course should also explain the structure and functioning of the controller and its software. This paper presents a description of this presentation.

    19. Theoretical concepts fpr fractal growth

      NASA Astrophysics Data System (ADS)

      Pietronero, L.

      1989-09-01

      After the introduction of fractal geometry by Benoit Mandelbrot the key problem is to understand why nature gives rise to fractal structures. This implies the formulation of models of fractal growth based on physical phenomena and the subsequent understanding of their mathematical structure in the same sense as the renormalization group has allowed to understand sing-type models. The models of diffusion-limited aggregation and the more general dielectric breakdown model, based on iterative processes governed by the Laplace equation and a stochastic field, have a clear physical meaning and they spontaneously evolve into random fractal structures of great complexity. From a theoretical point of view however it is not possible to describe them within usual concepts. Recently we have introduced a new theoretical framework for this class of problems. This clarifies the origin of fractal structures in these models and provides a systematic method for the calculation of the fractal dimension and the multifractal properties. Here we summarize the basic ideas of this new approach and report about recent developments.

    20. Human-Centered Fusion Framework

      SciTech Connect

      Posse, Christian; White, Amanda M.; Beagley, Nathaniel

      2007-05-16

      In recent years the benefits of fusing signatures extracted from large amounts of distributed and/or heterogeneous data sources have been largely documented in various problems ranging from biological protein function prediction to cyberspace monitoring. In spite of significant progress in information fusion research, there is still no formal theoretical framework for defining various types of information fusion systems, defining and analyzing relations among such types, and designing information fusion systems using a formal method approach. Consequently, fusion systems are often poorly understood, are less than optimal, and/or do not suit user needs. To start addressing these issues, we outline a formal humancentered fusion framework for reasoning about fusion strategies. Our approach relies on a new taxonomy for fusion strategies, an alternative definition of information fusion in terms of parameterized paths in signature related spaces, an algorithmic formalization of fusion strategies and a library of numeric and dynamic visual tools measuring the impact as well as the impact behavior of fusion strategies. Using a real case of intelligence analysis we demonstrate that the proposed framework enables end users to rapidly 1) develop and implement alternative fusion strategies, 2) understand the impact of each strategy, 3) compare the various strategies, and 4) perform the above steps without having to know the mathematical foundations of the framework. We also demonstrate that the human impact on a fusion system is critical in the sense that small changes in strategies do not necessarily correspond to small changes in results.

    1. Consensus theoretic classification methods

      NASA Technical Reports Server (NTRS)

      Benediktsson, Jon A.; Swain, Philip H.

      1992-01-01

      Consensus theory is adopted as a means of classifying geographic data from multiple sources. The foundations and usefulness of different consensus theoretic methods are discussed in conjunction with pattern recognition. Weight selections for different data sources are considered and modeling of non-Gaussian data is investigated. The application of consensus theory in pattern recognition is tested on two data sets: 1) multisource remote sensing and geographic data and 2) very-high-dimensional remote sensing data. The results obtained using consensus theoretic methods are found to compare favorably with those obtained using well-known pattern recognition methods. The consensus theoretic methods can be applied in cases where the Gaussian maximum likelihood method cannot. Also, the consensus theoretic methods are computationally less demanding than the Gaussian maximum likelihood method and provide a means for weighting data sources differently.

    2. A New Theoretical Psychology?

      ERIC Educational Resources Information Center

      Longuet-Higgins, H. C.

      1982-01-01

      It is suggested that the study of artificial intelligence can provide ways of thinking about the human mind that are potentially valuable in formulating cognitive theories. Theoretical psychology is proposed as an appropriate classification for this branch of theory. (MSE)

    3. Evaluation of Learning Materials: A Holistic Framework

      ERIC Educational Resources Information Center

      Bundsgaard, Jeppe; Hansen, Thomas Illum

      2011-01-01

      This paper presents a holistic framework for evaluating learning materials and designs for learning. A holistic evaluation comprises investigations of the potential learning potential, the actualised learning potential, and the actual learning. Each aspect is explained and exemplified through theoretical models and definitions. (Contains 3 figures…

    4. Information Literacy: A Framework for Higher Education.

      ERIC Educational Resources Information Center

      Bruce, Christine Susan

      1995-01-01

      Discusses information literacy and presents a theoretical framework for higher education. Highlights include characteristics of an information literate person, including independent self-directed learning and the use of information technology; information literacy education strategies in the academic curriculum; evaluating information literacy…

    5. 37. Fore and main masts, and main boom lying in ...

      Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

      37. Fore and main masts, and main boom lying in storage yard. Stern of Museum Ship Wavetreet to left in photograph. - Schooner "Lettie G. Howard", South Street Seaport Museum, New York, New York County, NY

    6. 22. View showing main anchor arm, as viewed from main ...

      Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

      22. View showing main anchor arm, as viewed from main cantilever arm looking south. Note upper chord eyebar arrangement. - Williamstown-Marietta Bridge, Spanning Ohio River between Williamstown & Marietta, Williamstown, Wood County, WV

    7. Are Post-Main Sequence Planets Doomed?

      NASA Astrophysics Data System (ADS)

      Villaver, E.

      2014-04-01

      Post-main sequence evolution directly affects the survival of planetary and sub-planetary mass bodies. Planets orbiting evolved stars undergo orbital evolution under the influence of tides and mass-loss, can be ejected, evaporated, and suffer multiple-body instabilities. The conditions on the planet surface are expected to be modified as well as the result of the evolution of the star. I will discuss the new limits that the theoretical studies allow us to set on the survival and habitability of planets as the star runs out of its hydrogen fuel.

    8. Theoretical Perspectives on the Internationalization of Firms

      ERIC Educational Resources Information Center

      Rask, Morten; Strandskov, Jesper; Hakonsson, Dorthe Dojbak

      2008-01-01

      The purpose of this article is to build a coherent framework of the four main theories relating to the internationalization of firms, in order to facilitate better business teaching and research. Yet, theories of the internationalization of firms are broad and rest on different underlying assumptions. With the purpose of clarifying the potential…

    9. 2014 Maine Earth Science Day

      USGS Multimedia Gallery

      On October 15, 2014 Maine Earth Science Day was held at the Maine State Museum in Augusta. The USGS was represented by Charlie Culbertson, left, and Nick Waldron, right. This photo was taken as the two were packing up for the day, and shows a main feature of the table, a touch screen display with th...

    10. MAINE MUSSEL SEED CONSERVATION AREAS

      EPA Science Inventory

      SEED shows point locations of Maine mussel seed conservation areas at 1:24,000 scale. Data for this coverage were screen digitized on a 1:24000 scale base using descriptions contained in Maine Department of Marine Resources (MDMR) rules. Coastal arcs from Maine Office of GIS 1:24...

    11. Peer-Formativity: A Framework for Academic Writing

      ERIC Educational Resources Information Center

      Murray, Rowena; Thow, Morag

      2014-01-01

      The system currently deployed to assess research outputs in higher education can influence what, how and for whom academics write; for some it may determine whether or not they write at all. This article offers a framework for negotiating this performative context--the writing meeting. This framework uses the established theoretical underpinning…

    12. A Future-Oriented Retirement Transition Adjustment Framework

      ERIC Educational Resources Information Center

      Hesketh, Beryl; Griffin, Barbara; Loh, Vanessa

      2011-01-01

      This theoretical paper presents a person-environment fit framework that extends the Minnesota Theory of Work Adjustment to retirement transition and adjustment. The proposed Retirement Transition and Adjustment Framework (RTAF) also accommodates dynamic intra-individual and environment change over time, configural combinations of variables, and an…

    13. A Future-Oriented Retirement Transition Adjustment Framework

      ERIC Educational Resources Information Center

      Hesketh, Beryl; Griffin, Barbara; Loh, Vanessa

      2011-01-01

      This theoretical paper presents a person-environment fit framework that extends the Minnesota Theory of Work Adjustment to retirement transition and adjustment. The proposed Retirement Transition and Adjustment Framework (RTAF) also accommodates dynamic intra-individual and environment change over time, configural combinations of variables, and an…

    14. [Once again: theoretical pathology].

      PubMed

      Bleyl, U

      2010-07-01

      Theoretical pathology refers to the attempt to reintroduce methodical approaches from the humanities, philosophical logic and "gestalt philosophy" into medical research and pathology. Diseases, in particular disease entities and more complex polypathogenetic mechanisms of disease, have a "gestalt quality" due to the significance of their pathophysiologic coherence: they have a "gestalt". The Research group Theoretical Pathology at the Academy of Science in Heidelberg are credited with having revitalized the philosophical notion of "gestalt" for morphological and pathological diagnostics. Gestalt means interrelated schemes of pathophysiological significance in the mind of the diagnostician. In pathology, additive and associative diagnostic are simply not possible without considering the notion of synthetic entities in Kant's logic. PMID:19760245

    15. Public health and health promotion capacity at national and regional level: a review of conceptual frameworks.

      PubMed

      Aluttis, Christoph; den Broucke, Stephan Van; Chiotan, Cristina; Costongs, Caroline; Michelsen, Kai; Brand, Helmut

      2014-03-26

      The concept of capacity building for public health has gained much attention during the last decade. National as well as international organizations increasingly focus their efforts on capacity building to improve performance in the health sector. During the past two decades, a variety of conceptual frameworks have been developed which describe relevant dimensions for public health capacity. Notably, these frameworks differ in design and conceptualization. This paper therefore reviews the existing conceptual frameworks and integrates them into one framework, which contains the most relevant dimensions for public health capacity at the country- or regional level. A comprehensive literature search was performed to identify frameworks addressing public health capacity building at the national or regional level. We content-analysed these frameworks to identify the core dimensions of public health capacity. The dimensions were subsequently synthesized into a set of thematic areas to construct a conceptual framework which describes the most relevant dimensions for capacities at the national- or regional level. The systematic review resulted in the identification of seven core domains for public health capacity: resources, organizational structures, workforce, partnerships, leadership and governance, knowledge development and country specific context. Accordingly, these dimensions were used to construct a framework, which describes these core domains more in detail. Our research shows that although there is no generally agreedupon model of public health capacity, a number of key domains for public health and health promotion capacity are consistently recurring in existing frameworks, regardless of their geographical location or thematic area. As only little work on the core concepts of public health capacities has yet taken place, this study adds value to the discourse by identifying these consistencies across existing frameworks and by synthesising them into a new framework. The framework proposed in this paper can act as a theoretical guide for academic researchers and institutions to set up their own public health capacity assessment. Significance for public healthAs the concept of public health capacities is increasingly debated across countries and national/ international organizations, there is no consensus on the main dimensions of public health capacity. This paper therefore provides a rigorous review of currently existing frameworks, which describe public health capacities at the national or regional level. The main objective is to highlight commonalities among these frameworks, and propose a country-level framework which integrates all reoccurring dimensions. Such a comparison can yield vital information on those dimensions for public health capacities, which are common across all frameworks, and hence could be considered indispensable, irrespective of their context or geographic origin. As such, this review and the subsequent presentation of a conceptual framework is targeted at academic researchers and policy makers, who are interested in setting up a capacity mapping process and who are looking for concepts and frameworks on which they can base their work. PMID:25170508

    16. Public Health and Health Promotion Capacity at National and Regional Level: A Review of Conceptual Frameworks

      PubMed Central

      Aluttis, Christoph; den Broucke, Stephan Van; Chiotan, Cristina; Costongs, Caroline; Michelsen, Kai; Brand, Helmut

      2014-01-01

      The concept of capacity building for public health has gained much attention during the last decade. National as well as international organizations increasingly focus their efforts on capacity building to improve performance in the health sector. During the past two decades, a variety of conceptual frameworks have been developed which describe relevant dimensions for public health capacity. Notably, these frameworks differ in design and conceptualization. This paper therefore reviews the existing conceptual frameworks and integrates them into one framework, which contains the most relevant dimensions for public health capacity at the country- or regional level. A comprehensive literature search was performed to identify frameworks addressing public health capacity building at the national or regional level. We content-analysed these frameworks to identify the core dimensions of public health capacity. The dimensions were subsequently synthesized into a set of thematic areas to construct a conceptual framework which describes the most relevant dimensions for capacities at the national- or regional level. The systematic review resulted in the identification of seven core domains for public health capacity: resources, organizational structures, workforce, partnerships, leadership and governance, knowledge development and country specific context. Accordingly, these dimensions were used to construct a framework, which describes these core domains more in detail. Our research shows that although there is no generally agreedupon model of public health capacity, a number of key domains for public health and health promotion capacity are consistently recurring in existing frameworks, regardless of their geographical location or thematic area. As only little work on the core concepts of public health capacities has yet taken place, this study adds value to the discourse by identifying these consistencies across existing frameworks and by synthesising them into a new framework. The framework proposed in this paper can act as a theoretical guide for academic researchers and institutions to set up their own public health capacity assessment. Significance for public health As the concept of public health capacities is increasingly debated across countries and national/ international organizations, there is no consensus on the main dimensions of public health capacity. This paper therefore provides a rigorous review of currently existing frameworks, which describe public health capacities at the national or regional level. The main objective is to highlight commonalities among these frameworks, and propose a country-level framework which integrates all reoccurring dimensions. Such a comparison can yield vital information on those dimensions for public health capacities, which are common across all frameworks, and hence could be considered indispensable, irrespective of their context or geographic origin. As such, this review and the subsequent presentation of a conceptual framework is targeted at academic researchers and policy makers, who are interested in setting up a capacity mapping process and who are looking for concepts and frameworks on which they can base their work. PMID:25170508

    17. TIMSS 2007 Assessment Frameworks

      ERIC Educational Resources Information Center

      Mullis, Ina V. S.; Martin, Michael O.; Ruddock, Graham J.; O'Sullivan, Christine Y.; Arora, Alka; Erberber, Ebru

      2005-01-01

      Developing the Trends in International Mathematics and Science Study (TIMSS) 2007 Assessment Frameworks represents an extensive collaborative effort involving individuals and expert groups from more than 60 countries around the world. The document contains three frameworks for implementing TIMSS 2007--the Mathematics Framework, the Science…

    18. Choices, Frameworks and Refinement

      NASA Technical Reports Server (NTRS)

      Campbell, Roy H.; Islam, Nayeem; Johnson, Ralph; Kougiouris, Panos; Madany, Peter

      1991-01-01

      In this paper we present a method for designing operating systems using object-oriented frameworks. A framework can be refined into subframeworks. Constraints specify the interactions between the subframeworks. We describe how we used object-oriented frameworks to design Choices, an object-oriented operating system.

    19. Elementary Integrated Curriculum Framework

      ERIC Educational Resources Information Center

      Montgomery County Public Schools, 2010

      2010-01-01

      The Elementary Integrated Curriculum (EIC) Framework is the guiding curriculum document for the Elementary Integrated Curriculum and represents the elementary portion of the Montgomery County (Maryland) Public Schools (MCPS) Pre-K-12 Curriculum Frameworks. The EIC Framework contains the detailed indicators and objectives that describe what…

    20. Maine Indians: Topical Bibliography of Books in Maine State Library.

      ERIC Educational Resources Information Center

      1975

      Citations relative to the American Indians of Maine are presented in this topical bibliography of books currently located in the Maine State Library. The following are indicative of the subject topics and the number of citations to be found under each topic: (1) Antiquities (7); (2) Art (2); (3) Bibliography (1); (4) Government Relations (2); (5)…

    1. View of the main interior space facing east. The main ...

      Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

      View of the main interior space facing east. The main entry is on the left hand side at the rear. The exit to the deck is to the right. - San Luis Yacht Club, Avila Pier, South of Front Street, Avila Beach, San Luis Obispo County, CA

    2. 18. MAIN FLOOR HOLDING TANKS Main floor, looking at ...

      Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

      18. MAIN FLOOR - HOLDING TANKS Main floor, looking at holding tanks against the west wall, from which sluice gates are seen protruding. Right foreground-wooden holding tanks. Note narrow wooden flumes through which fish were sluiced into holding and brining tanks. - Hovden Cannery, 886 Cannery Row, Monterey, Monterey County, CA

    3. 12. Main cabin, interior view of living room with main ...

      Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

      12. Main cabin, interior view of living room with main cross beams, purlins and decking, fireplace in rear. Note twisted pine light fixture in center of photograph; view to southeast. - M.T. & Jennie H. Deaton Property, Big Springs Summer Home Area, Lot 2, Block N, Island Park, Fremont County, ID

    4. Discipline: A Theoretical Perspective

      ERIC Educational Resources Information Center

      Penta, Gerard C.

      1977-01-01

      Six postulates are developed concerning the concept of discipline (both academic and behavioral) which, if used as a theoretical basis in the formulation and administration of particular behavioral discipline policies, will result in a change of discipline methodology--not different in degree of refinement, but different in kind. (MJB)

    5. A Theoretical Trombone

      ERIC Educational Resources Information Center

      LoPresto, Michael C.

      2014-01-01

      What follows is a description of a theoretical model designed to calculate the playing frequencies of the musical pitches produced by a trombone. The model is based on quantitative treatments that demonstrate the effects of the flaring bell and cup-shaped mouthpiece sections on these frequencies and can be used to calculate frequencies that…

    6. A Theoretical Trombone

      ERIC Educational Resources Information Center

      LoPresto, Michael C.

      2014-01-01

      What follows is a description of a theoretical model designed to calculate the playing frequencies of the musical pitches produced by a trombone. The model is based on quantitative treatments that demonstrate the effects of the flaring bell and cup-shaped mouthpiece sections on these frequencies and can be used to calculate frequencies that…

    7. A new pressure ulcer conceptual framework

      PubMed Central

      Coleman, Susanne; Nixon, Jane; Keen, Justin; Wilson, Lyn; McGinnis, Elizabeth; Dealey, Carol; Stubbs, Nikki; Farrin, Amanda; Dowding, Dawn; Schols, Jos MGA; Cuddigan, Janet; Berlowitz, Dan; Jude, Edward; Vowden, Peter; Schoonhoven, Lisette; Bader, Dan L; Gefen, Amit; Oomens, Cees WJ; Nelson, E Andrea

      2014-01-01

      Aim This paper discusses the critical determinants of pressure ulcer development and proposes a new pressure ulcer conceptual framework. Background Recent work to develop and validate a new evidence-based pressure ulcer risk assessment framework was undertaken. This formed part of a Pressure UlceR Programme Of reSEarch (RP-PG-0407-10056), funded by the National Institute for Health Research. The foundation for the risk assessment component incorporated a systematic review and a consensus study that highlighted the need to propose a new conceptual framework. Design Discussion Paper. Data Sources The new conceptual framework links evidence from biomechanical, physiological and epidemiological evidence, through use of data from a systematic review (search conducted March 2010), a consensus study (conducted December 2010–2011) and an international expert group meeting (conducted December 2011). Implications for Nursing A new pressure ulcer conceptual framework incorporating key physiological and biomechanical components and their impact on internal strains, stresses and damage thresholds is proposed. Direct and key indirect causal factors suggested in a theoretical causal pathway are mapped to the physiological and biomechanical components of the framework. The new proposed conceptual framework provides the basis for understanding the critical determinants of pressure ulcer development and has the potential to influence risk assessment guidance and practice. It could also be used to underpin future research to explore the role of individual risk factors conceptually and operationally. Conclusion By integrating existing knowledge from epidemiological, physiological and biomechanical evidence, a theoretical causal pathway and new conceptual framework are proposed with potential implications for practice and research. PMID:24684197

    8. Information-theoretic constraints on correlations with indefinite causal order

      NASA Astrophysics Data System (ADS)

      Ibnouhsein, Issam; Grinbaum, Alexei

      2015-10-01

      Reconstructions of quantum theory usually implicitly assume that experimental events are ordered within a global causal structure. The process matrix framework accommodates quantum correlations that violate an inequality verified by all causally ordered correlations. Using a generalized probabilistic framework, we propose three principles constraining bipartite correlations to the quantum bound. Our approach highlights the role of a measure of dependence other than mutual information for an information-theoretic reconstruction of causal structures in quantum theory.

    9. Maine Agricultural Foods. Project SEED.

      ERIC Educational Resources Information Center

      Beaulieu, Peter; Ossenfort, Pat

      This paper describes an activity-based program that teaches students in grades 4-12 about the importance of Maine agriculture in their lives. Specifically, the goal is to increase student awareness of how the foods they eat are planted, harvested, and processed. The emphasis is on crops grown in Maine such as potatoes, broccoli, peas, blueberries,…

    10. Maine Indians: A Brief Summary.

      ERIC Educational Resources Information Center

      1971

      The Indians of Maine, descendants of Algonquian linguistic stock, number approximately 1800 and reside on 3 reservations totalling 22,600 acres of land. Most of the reservation land is forested, with important economic and recreational advantages in terms of timber production and hunting and fishing opportunities. In 1965, Maine became the first…

    11. Maine: Early Head Start Initiatives

      ERIC Educational Resources Information Center

      Center for Law and Social Policy, Inc. (CLASP), 2012

      2012-01-01

      Maine has two initiatives that build on Early Head Start (EHS). The first initiative, Fund for a Healthy Maine, has since 2001 provided tobacco settlement money to existing Head Start and EHS programs to expand the number of children who receive full-day, full-year services. Local programs have the option of using these funds for EHS, depending on…

    12. Space Shuttle Main Engine Manufacturing

      NASA Technical Reports Server (NTRS)

      1977-01-01

      A workman reams holes to the proper size and aligment in the Space Shuttle Main Engine's main injector body, through which propellants will pass through on their way into the engine's combustion chamber. Rockwell International's Rocketdyne Division plant produced the engines under contract to the Marshall Space Flight Center.

    13. MAINE ATLANTIC SALMON HABITAT - GENERAL

      EPA Science Inventory

      ASDENN00 describes, at 1:24,000 scale, important Atlantic salmon habitat of the Dennys River in Maine. The coverage was developed from field surveys conducted on the Dennys River in Maine by staff of the Atlantic Salmon Authority and U.S. Fish and Wildlife Service. This survey wa...

    14. MAINE LANDS OVER 2700 FEET

      EPA Science Inventory

      MECON2700 contains areas in Maine with elevations greater than 2700 feet, generated from USGS 1:250,000 DEMs. Areas above 2700 feet are regulated by the Maine Land Use Regulation Commission (MELURC). Areas were generated from USGS 1:250,000 scale digital elevation models using A...

    15. Maine Indians: A Brief Summary.

      ERIC Educational Resources Information Center

      1971

      The Indians of Maine, descendants of Algonquian linguistic stock, number approximately 1800 and reside on 3 reservations totalling 22,600 acres of land. Most of the reservation land is forested, with important economic and recreational advantages in terms of timber production and hunting and fishing opportunities. In 1965, Maine became the first…

    16. Main Propulsion Test Article (MPTA)

      NASA Technical Reports Server (NTRS)

      Snoddy, Cynthia

      2010-01-01

      Scope: The Main Propulsion Test Article integrated the main propulsion subsystem with the clustered Space Shuttle Main Engines, the External Tank and associated GSE. The test program consisted of cryogenic tanking tests and short- and long duration static firings including gimbaling and throttling. The test program was conducted on the S1-C test stand (Position B-2) at the National Space Technology Laboratories (NSTL)/Stennis Space Center. 3 tanking tests and 20 hot fire tests conducted between December 21 1 1977 and December 17, 1980 Configuration: The main propulsion test article consisted of the three space shuttle main engines, flightweight external tank, flightweight aft fuselage, interface section and a boilerplate mid/fwd fuselage truss structure.

    17. A theoretical trombone

      NASA Astrophysics Data System (ADS)

      LoPresto, Michael C.

      2014-09-01

      What follows is a description of a theoretical model designed to calculate the playing frequencies of the musical pitches produced by a trombone. The model is based on quantitative treatments that demonstrate the effects of the flaring bell and cup-shaped mouthpiece sections on these frequencies and can be used to calculate frequencies that compare well to both the desired frequencies of the musical pitches and those actually played on a real trombone.

    18. Contextual analysis framework for bursty dynamics

      NASA Astrophysics Data System (ADS)

      Jo, Hang-Hyun; Pan, Raj Kumar; Perotti, Juan I.; Kaski, Kimmo

      2013-06-01

      To understand the origin of bursty dynamics in natural and social processes we provide a general analysis framework in which the temporal process is decomposed into subprocesses and then the bursts in subprocesses, called contextual bursts, are combined to collective bursts in the original process. For the combination of subprocesses, it is required to consider the distribution of different contexts over the original process. Based on minimal assumptions for interevent time statistics, we present a theoretical analysis for the relationship between contextual and collective interevent time distributions. Our analysis framework helps to exploit contextual information available in decomposable bursty dynamics.

    19. Panorama of theoretical physics

      NASA Astrophysics Data System (ADS)

      Mimouni, J.

      2012-06-01

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

    20. Theoretical Developments in SUSY

      NASA Astrophysics Data System (ADS)

      Shifman, M.

      2009-01-01

      I am proud that I was personally acquainted with Julius Wess. We first met in 1999 when I was working on the Yuri Golfand Memorial Volume (The Many Faces of the Superworld, World Scientific, Singapore, 2000). I invited him to contribute, and he accepted this invitation with enthusiasm. After that, we met many times, mostly at various conferences in Germany and elsewhere. I was lucky to discuss with Julius questions of theoretical physics, and hear his recollections on how supersymmetry was born. In physics Julius was a visionary, who paved the way to generations of followers. In everyday life he was a kind and modest person, always ready to extend a helping hand to people who were in need of his help. I remember him telling me how concerned he was about the fate of theoretical physicists in Eastern Europe after the demise of communism. His ties with Israeli physicists bore a special character. I am honored by the opportunity to contribute an article to the Julius Wess Memorial Volume. I will review theoretical developments of the recent years in non-perturbative supersymmetry.

    1. Embedded Logging Framework for Spacecrafts

      NASA Astrophysics Data System (ADS)

      Dannemann, Frank; Montenegro, Sergio

      2013-08-01

      During the different development phases of a spacecraft there exist various kind of information worlds, which often hold the same kind of content. In this paper we present an approach that can be seen as a first step to combine these worlds. An embedded software framework is introduced, which takes over the functionality of the internal debugging features of the system on the one hand, and on the other hand is a possible candidate for substituting the system's telemetry application, which is responsible for sending spacecraft status information to the ground station. Taking a minimal implementation of the framework, it's advantages by using it in the context of a satellite's console-based debug statements mainly needed for integration and testing purposes are shown in a practical use case.

    2. EXHAUST MAIN PERSONNEL EXPOSURE CALCULATION

      SciTech Connect

      S. Su

      1999-09-29

      The purpose of this activity is to identify and determine potential radiation hazards in the service exhaust main due to a waste package leakage from an emplacement drift. This work supports the subsurface ventilation system design for the EDA II, which consists of an accessible service exhaust main for personnel, and an exhaust main for hot air flow. The objective is to provide the necessary radiation exposure calculations to determine if the service exhaust main is accessible following a waste package leak. This work includes the following items responsive to the stated purpose and objective: Calculate the limiting transient radiation exposure of personnel in the service exhaust main due to the passage of airborne radioactive material through the ventilation raise and connecting horizontal raise to the exhaust main in the event of a leaking waste package Calculate the potential exposures to maintenance workers in the service exhaust main from residual radioactive material deposited inside of the ventilation raise and connecting horizontal raise This calculation is limited to external radiation only, since the airborne and contamination sources will be contained in the ventilation raise and connecting horizontal raise.

    3. Quality Attribute Techniques Framework

      NASA Astrophysics Data System (ADS)

      Chiam, Yin Kia; Zhu, Liming; Staples, Mark

      The quality of software is achieved during its development. Development teams use various techniques to investigate, evaluate and control potential quality problems in their systems. These “Quality Attribute Techniques” target specific product qualities such as safety or security. This paper proposes a framework to capture important characteristics of these techniques. The framework is intended to support process tailoring, by facilitating the selection of techniques for inclusion into process models that target specific product qualities. We use risk management as a theory to accommodate techniques for many product qualities and lifecycle phases. Safety techniques have motivated the framework, and safety and performance techniques have been used to evaluate the framework. The evaluation demonstrates the ability of quality risk management to cover the development lifecycle and to accommodate two different product qualities. We identify advantages and limitations of the framework, and discuss future research on the framework.

    4. Distributed visualization framework architecture

      NASA Astrophysics Data System (ADS)

      Mishchenko, Oleg; Raman, Sundaresan; Crawfis, Roger

      2010-01-01

      An architecture for distributed and collaborative visualization is presented. The design goals of the system are to create a lightweight, easy to use and extensible framework for reasearch in scientific visualization. The system provides both single user and collaborative distributed environment. System architecture employs a client-server model. Visualization projects can be synchronously accessed and modified from different client machines. We present a set of visualization use cases that illustrate the flexibility of our system. The framework provides a rich set of reusable components for creating new applications. These components make heavy use of leading design patterns. All components are based on the functionality of a small set of interfaces. This allows new components to be integrated seamlessly with little to no effort. All user input and higher-level control functionality interface with proxy objects supporting a concrete implementation of these interfaces. These light-weight objects can be easily streamed across the web and even integrated with smart clients running on a user's cell phone. The back-end is supported by concrete implementations wherever needed (for instance for rendering). A middle-tier manages any communication and synchronization with the proxy objects. In addition to the data components, we have developed several first-class GUI components for visualization. These include a layer compositor editor, a programmable shader editor, a material editor and various drawable editors. These GUI components interact strictly with the interfaces. Access to the various entities in the system is provided by an AssetManager. The asset manager keeps track of all of the registered proxies and responds to queries on the overall system. This allows all user components to be populated automatically. Hence if a new component is added that supports the IMaterial interface, any instances of this can be used in the various GUI components that work with this interface. One of the main features is an interactive shader designer. This allows rapid prototyping of new visualization renderings that are shader-based and greatly accelerates the development and debug cycle.

    5. Pulsations in pre-main sequence stars

      NASA Astrophysics Data System (ADS)

      Zwintz, Konstanze

      2015-08-01

      Asteroseismology has been proven to be a successful tool to unravel details of the internal structure for different types of stars in various stages of evolution well after birth. We can now show that it has similar power for pre-main sequence (pre-MS) objects.Pre-MS stars with masses between ~1 and 6 solar masses that have recently been formed and gain their energy mainly from gravitational contraction can become vibrationally unstable during their evolution to the main sequence. Within the past ~15 years, several dozens of pulsating pre-MS stars were discovered using data obtained from ground and from space (i.e., using the space telescopes MOST and CoRoT). Depending on their masses, pre-MS stars can show three different types of pulsations: (i) delta Scuti type p-mode pulsations, (ii) gamma Doradus like g-mode oscillations and (iii) g-mode Slowly Pulsating B star pulsations.Our asteroseismic investigations yielded new insights into the connection between pulsation and early stellar evolution: We revealed a relation between the stars' oscillatory behaviour and their relative evolutionary stages that might lead us to a model-independent determination of the stars' fundamental parameters. With this we will be able to put constraints on theoretical models and help to answer some of the yet open questions in early stellar evolution.

    6. IBRD Operational Decision Framework

      SciTech Connect

      Greenwalt, R; Hibbard, W; Raber, E; Carlsen, T; Folks, K; MacQueen, D; Mancieri, S; Bunt, T; Richards, J; Hirabayashi-Dethier, J

      2010-11-12

      The IBRD Operational Decision Framework in this document is an expansion of an emerging general risk management framework under development by an interagency working group. It provides the level of detail necessary to develop a general Consequence Management Guidance Document for biological contamination remediation and restoration. It is the intent of this document to support both wide area and individual site remediation and restoration activities. This product was initiated as a portion of the IBRD Task 1 Systems Analysis to aid in identification of wide area remediation and restoration shortcomings and gaps. The draft interagency general risk management framework was used as the basis for the analysis. The initial Task 1 analysis document expanded the draft interagency framework to a higher level of resolution, building on both the logic structure and the accompanying text explanations. It was then employed in a qualitative manner to identify responsible agencies, data requirements, tool requirements, and current capabilities for each decision and task. This resulted in identifying shortcomings and gaps needing resolution. Several meetings of a joint LLNL/SNL working group reviewed and approved the initial content of this analysis. At the conclusion of Task 1, work continued on the expanded framework to generate this Operational Decision Framework which is consistent with the existing interagency general risk management framework. A large LLNL task group met repeatedly over a three-month period to develop the expanded framework, coordinate the framework with the biological remediation checklist, and synchronize the logic with the Consequence Management Plan table of contents. The expanded framework was briefed at a large table top exercise reviewing the interagency risk management framework. This exercise had representation from major US metropolitan areas as well as national agencies. This product received positive comments from the participants. Upon completion of the Operational Decision Framework, another joint LLNL/SNL working group conducted a day-long review. Identified modifications were made to the document, resulting in the included product.

    7. A framework to analyse gender bias in epidemiological research

      PubMed Central

      Ruiz‐Cantero, María Teresa; Vives‐Cases, Carmen; Artazcoz, Lucía; Delgado, Ana; del Mar García Calvente, Maria; Miqueo, Consuelo; Montero, Isabel; Ortiz, Rocío; Ronda, Elena; Ruiz, Isabel; Valls, Carme

      2007-01-01

      The design and analysis of research may cause systematic gender dependent errors to be produced in results because of gender insensitivity or androcentrism. Gender bias in research could be defined as a systematically erroneous gender dependent approach related to social construct, which incorrectly regards women and men as similar/different. Most gender bias can be found in the context of discovery (development of hypotheses), but it has also been found in the context of justification (methodological process), which must be improved. In fact, one of the main effects of gender bias in research is partial or incorrect knowledge in the results, which are systematically different from the real values. This paper discusses some forms of conceptual and methodological bias that may affect women's health. It proposes a framework to analyse gender bias in the design and analysis of research carried out on women's and men's health problems, and on specific women's health issues. Using examples, the framework aims to show the different theoretical perspectives in a social or clinical research context where forms of selection, measurement and confounding bias are produced as a result of gender insensitivity. Finally, this paper underlines the importance of re‐examining results so that they may be reinterpreted to produce new gender based knowledge. PMID:18000118

    8. A Markov Random Field Groupwise Registration Framework for Face Recognition

      PubMed Central

      Liao, Shu; Shen, Dinggang; Chung, Albert C.S.

      2014-01-01

      In this paper, we propose a new framework for tackling face recognition problem. The face recognition problem is formulated as groupwise deformable image registration and feature matching problem. The main contributions of the proposed method lie in the following aspects: (1) Each pixel in a facial image is represented by an anatomical signature obtained from its corresponding most salient scale local region determined by the survival exponential entropy (SEE) information theoretic measure. (2) Based on the anatomical signature calculated from each pixel, a novel Markov random field based groupwise registration framework is proposed to formulate the face recognition problem as a feature guided deformable image registration problem. The similarity between different facial images are measured on the nonlinear Riemannian manifold based on the deformable transformations. (3) The proposed method does not suffer from the generalizability problem which exists commonly in learning based algorithms. The proposed method has been extensively evaluated on four publicly available databases: FERET, CAS-PEAL-R1, FRGC ver 2.0, and the LFW. It is also compared with several state-of-the-art face recognition approaches, and experimental results demonstrate that the proposed method consistently achieves the highest recognition rates among all the methods under comparison. PMID:25506109

    9. Humboldt River main stem, Nevada

      USGS Publications Warehouse

      Warmath, Eric; Medina, Rose L.

      2001-01-01

      This data set contains the main stem of the Humboldt River as defined by Humboldt Project personnel of the U.S. Geological Survey Nevada District, 2001. The data set was digitized on screen using digital orthophoto quadrangles from 1994.

    10. Geospatial evaluations of potato production systems in Maine

      Technology Transfer Automated Retrieval System (TEKTRAN)

      Maine consistently ranks in the top ten potato (Solanum tuberosum L.) production areas though yields are substantially lower than the mid- and western USA. Geospatial frameworks help resolve patterns and trends in production environments (at multiple scales) that may enable improvements in adaptive ...

    11. Selection Policy: Maine State Library, Reader and Information Services Division.

      ERIC Educational Resources Information Center

      Wismer, Donald

      The materials selection policy of the public services division of the Maine State Library analyzes the statutory language under which the library operates, and incorporates the requirements of that language into a broader framework of demand, collection quality, and long term value. Collection development is discussed by Dewey class, followed by…

    12. LSRA with Shuttle main gear

      NASA Technical Reports Server (NTRS)

      1993-01-01

      A space shuttle landing gear system is visible between the two main landing gear components on this NASA CV-990, modified as a Landing Systems Research Aircraft. The space shuttle landing gear test unit, operated by a high-pressure hydraulic system, allowed engineers to assess and document the performance of space shuttle main and nose landing gear systems, tires and wheel assemblies, plus braking and nose wheel steering performance.

    13. Pre-main-sequence evolution

      NASA Technical Reports Server (NTRS)

      Sofia, S.; Kawaler, S.; Larson, R.; Pinsonneault, M.

      1991-01-01

      The primary uncertainty that remains concerning the premain sequence (PMS) stage of stellar evolution is the possible role of accretion in the hydrodynamic stage. Possible PMS evolution scenarios are presented with a view to extant or potentially obtainable observational data that may unravel the details of PMS evolution. Attention is given to recent evolution calculations which encompass the role of rotation; it is concluded that the rotational feature of PMS can be tested within the framework of the chemical abundance of trace elements in the solar system, on the sun, and on solar analogs of various ages.

    14. Theoretical Estimation of Fatigue Crack Initiation Life for Metallic Materials

      NASA Astrophysics Data System (ADS)

      Li, Chunwang; Sun, Qiang; Yang, Youshe; Li, Jing; Zhang, Guibin; Zhang, Zhongping

      2013-03-01

      The main purpose of this paper is to theoretically estimate fatigue crack initiation life of metallic materials using the three-parameter model. For this purpose, correlations between the three parameters and conventional mechanical properties are established. The three parameters are fatigue ductility coefficient, fatigue ductility exponent, and theoretical strain endurance limit. Based on the correlations, the three parameters can be theoretically estimated, and thus the fatigue crack initiation life of metallic materials can be predicted in the absence of fatigue test data.

    15. Theoretical Astrophysics at Fermilab

      NASA Technical Reports Server (NTRS)

      2004-01-01

      The Theoretical Astrophysics Group works on a broad range of topics ranging from string theory to data analysis in the Sloan Digital Sky Survey. The group is motivated by the belief that a deep understanding of fundamental physics is necessary to explain a wide variety of phenomena in the universe. During the three years 2001-2003 of our previous NASA grant, over 120 papers were written; ten of our postdocs went on to faculty positions; and we hosted or organized many workshops and conferences. Kolb and collaborators focused on the early universe, in particular and models and ramifications of the theory of inflation. They also studied models with extra dimensions, new types of dark matter, and the second order effects of super-horizon perturbations. S tebbins, Frieman, Hui, and Dodelson worked on phenomenological cosmology, extracting cosmological constraints from surveys such as the Sloan Digital Sky Survey. They also worked on theoretical topics such as weak lensing, reionization, and dark energy. This work has proved important to a number of experimental groups [including those at Fermilab] planning future observations. In general, the work of the Theoretical Astrophysics Group has served as a catalyst for experimental projects at Fennilab. An example of this is the Joint Dark Energy Mission. Fennilab is now a member of SNAP, and much of the work done here is by people formerly working on the accelerator. We have created an environment where many of these people made transition from physics to astronomy. We also worked on many other topics related to NASA s focus: cosmic rays, dark matter, the Sunyaev-Zel dovich effect, the galaxy distribution in the universe, and the Lyman alpha forest. The group organized and hosted a number of conferences and workshop over the years covered by the grant. Among them were:

    16. M dwarfs: Theoretical work

      NASA Technical Reports Server (NTRS)

      Mullan, Dermott J.

      1987-01-01

      Theoretical work on the atmospheres of M dwarfs has progressed along lines parallel to those followed in the study of other classes of stars. Such models have become increasingly sophisticated as improvements in opacities, in the equation of state, and in the treatment of convection were incorporated during the last 15 to 20 years. As a result, spectrophotometric data on M dwarfs can now be fitted rather well by current models. The various attempts at modeling M dwarf photospheres in purely thermal terms are summarized. Some extensions of these models to include the effects of microturbulence and magnetic inhomogeneities are presented.

    17. HERAFitter - an open source QCD fit framework

      NASA Astrophysics Data System (ADS)

      Sapronov, Andrey; HERAFitter Team

      2015-05-01

      The open source project HERAFitter was established to increase applicability of the QCD analysis in the hadron collider experiments. The framework may be used to extract parton density functions from a variety of experimental measurements and to assess the impact of different data on the parton density determination. It may also be employed to perform data consistency checks and to test theoretical models. This short article covers a parallel session contribution of the ACAT2014 conference.

    18. HERAFitter - an open source QCD fit framework

      NASA Astrophysics Data System (ADS)

      Sapronov, Andrey; Herafitter Team

      2014-11-01

      The HERAFitter project was established to increase applicability of the QCD analysis in the hadron collider experiments. The framework may be used to extract parton density functions from a variety of experimental measurements and to assess the impact of new data on the parton density determination. It may also be employed to perform data consistency checks and to test theoretical models. This short article covers a poster contribution on the BEACH2014 conference held at the Birmingham University.

    19. Remember the MaineRx.

      PubMed

      Kemp, Robert

      2014-02-01

      In 2000, Maine became the first state in the US to enact a law to establish maximum retail prices for prescription drugs for all qualified state residents-MaineRx. The purpose was to lower prescription drug prices for all eligible residents of the state. The state was to have the ability to negotiate manufacturer rebates and pharmacy discounts. Major drug manufacturers, represented by the Pharmaceutical Research and Manufacturers of America, challenged MaineRx in the courts, going to the Supreme Court where it was upheld in 2003. Fifteen other states enacted, proposed, or filed price-control bills in their state legislatures. The result would have been downward pressure on prices outside of the public programs, and the first instance of state-sponsored monopsony power in the US. MaineRx is viewed as one of the proximate causes of the pharmaceutical industry's successful lobbying effort to implement Medicare Part D in 2004. Medicare Part D is administered through private Pharmacy Benefit Managers (PBMs); it made administration via state government PBMs illegal. The lower prices that could have resulted from MaineRx-type laws did not occur and the magnitude of these reductions is commented upon. PMID:24420789

    20. P21 Framework Definitions

      ERIC Educational Resources Information Center

      Partnership for 21st Century Skills, 2009

      2009-01-01

      To help practitioners integrate skills into the teaching of core academic subjects, the Partnership for 21st Century Skills has developed a unified, collective vision for learning known as the Framework for 21st Century Learning. This Framework describes the skills, knowledge and expertise students must master to succeed in work and life; it is a…

    1. Science Curriculum Framework. Revised.

      ERIC Educational Resources Information Center

      Arkansas State Dept. of Education, Little Rock.

      This document presents the revised Arkansas Science Curriculum Framework (1999), which replaces the Science Curriculum Framework of 1994. Three strands--physical science systems, life science systems, and Earth science/space science systems--were identified using an integrated approach to provide guidance in the science curriculum. A glossary and…

    2. Frameworks of Educational Technology

      ERIC Educational Resources Information Center

      Ely, Donald

      2008-01-01

      This paper, written from a 20th-century perspective, traces the development of, and influences on, the field of instructional technology and attempts to describe a framework within which we can better understand the field. [This article is based on "Instructional Technology: Contemporary Frameworks" originally written by the author for the…

    3. Dark matter: theoretical perspectives.

      PubMed

      Turner, M S

      1993-06-01

      I both review and make the case for the current theoretical prejudice: a flat Universe whose dominant constituent is nonbaryonic dark matter, emphasizing that this is still a prejudice and not yet fact. The theoretical motivation for nonbaryonic dark matter is discussed in the context of current elementary-particle theory, stressing that (i) there are no dark-matter candidates within the "standard model" of particle physics, (ii) there are several compelling candidates within attractive extensions of the standard model of particle physics, and (iii) the motivation for these compelling candidates comes first and foremost from particle physics. The dark-matter problem is now a pressing issue in both cosmology and particle physics, and the detection of particle dark matter would provide evidence for "new physics." The compelling candidates are a very light axion (10(-6)-10(-4) eV), a light neutrino (20-90 eV), and a heavy neutralino (10 GeV-2 TeV). The production of these particles in the early Universe and the prospects for their detection are also discussed. I briefly mention more exotic possibilities for the dark matter, including a nonzero cosmological constant, superheavy magnetic monopoles, and decaying neutrinos. PMID:11607395

    4. Dark matter: theoretical perspectives.

      PubMed Central

      Turner, M S

      1993-01-01

      I both review and make the case for the current theoretical prejudice: a flat Universe whose dominant constituent is nonbaryonic dark matter, emphasizing that this is still a prejudice and not yet fact. The theoretical motivation for nonbaryonic dark matter is discussed in the context of current elementary-particle theory, stressing that (i) there are no dark-matter candidates within the "standard model" of particle physics, (ii) there are several compelling candidates within attractive extensions of the standard model of particle physics, and (iii) the motivation for these compelling candidates comes first and foremost from particle physics. The dark-matter problem is now a pressing issue in both cosmology and particle physics, and the detection of particle dark matter would provide evidence for "new physics." The compelling candidates are a very light axion (10(-6)-10(-4) eV), a light neutrino (20-90 eV), and a heavy neutralino (10 GeV-2 TeV). The production of these particles in the early Universe and the prospects for their detection are also discussed. I briefly mention more exotic possibilities for the dark matter, including a nonzero cosmological constant, superheavy magnetic monopoles, and decaying neutrinos. PMID:11607395

    5. Dark matter: Theoretical perspectives

      SciTech Connect

      Turner, M.S. |

      1993-01-01

      I both review and make the case for the current theoretical prejudice: a flat Universe whose dominant constituent is nonbaryonic dark matter, emphasizing that this is still a prejudice and not yet fact. The theoretical motivation for nonbaryonic dark matter is discussed in the context of current elementary-particle theory, stressing that: (1) there are no dark matter candidates within the standard model of particle physics; (2) there are several compelling candidates within attractive extensions of the standard model of particle physics; and (3) the motivation for these compelling candidates comes first and foremost from particle physics. The dark-matter problem is now a pressing issue in both cosmology and particle physics, and the detection of particle dark matter would provide evidence for ``new physics.`` The compelling candidates are: a very light axion ( 10{sup {minus}6} eV--10{sup {minus}4} eV); a light neutrino (20 eV--90 eV); and a heavy neutralino (10 GeV--2 TeV). The production of these particles in the early Universe and the prospects for their detection are also discussed. I briefly mention more exotic possibilities for the dark matter, including a nonzero cosmological constant, superheavy magnetic monopoles, and decaying neutrinos.

    6. Dark matter: Theoretical perspectives

      SciTech Connect

      Turner, M.S. . Enrico Fermi Inst. Fermi National Accelerator Lab., Batavia, IL )

      1993-01-01

      I both review and make the case for the current theoretical prejudice: a flat Universe whose dominant constituent is nonbaryonic dark matter, emphasizing that this is still a prejudice and not yet fact. The theoretical motivation for nonbaryonic dark matter is discussed in the context of current elementary-particle theory, stressing that: (1) there are no dark matter candidates within the standard model of particle physics; (2) there are several compelling candidates within attractive extensions of the standard model of particle physics; and (3) the motivation for these compelling candidates comes first and foremost from particle physics. The dark-matter problem is now a pressing issue in both cosmology and particle physics, and the detection of particle dark matter would provide evidence for new physics.'' The compelling candidates are: a very light axion ( 10[sup [minus]6] eV--10[sup [minus]4] eV); a light neutrino (20 eV--90 eV); and a heavy neutralino (10 GeV--2 TeV). The production of these particles in the early Universe and the prospects for their detection are also discussed. I briefly mention more exotic possibilities for the dark matter, including a nonzero cosmological constant, superheavy magnetic monopoles, and decaying neutrinos.

    7. Conceptualizing Environmental Refugees in Education: A Transformative Language-Learning Framework

      ERIC Educational Resources Information Center

      Goulah, Jason

      2010-01-01

      Environmental refugees are increasing worldwide. Consequently, a theoretical framework is necessary for conceptualizing them in education. This article breaks new ground by providing such a framework in education, in general, and bilingual-bicultural education, in particular. The framework is grounded in O'Sullivan's (1999, 2002) transformative…

    8. Conceptualizing Environmental Refugees in Education: A Transformative Language-Learning Framework

      ERIC Educational Resources Information Center

      Goulah, Jason

      2010-01-01

      Environmental refugees are increasing worldwide. Consequently, a theoretical framework is necessary for conceptualizing them in education. This article breaks new ground by providing such a framework in education, in general, and bilingual-bicultural education, in particular. The framework is grounded in O'Sullivan's (1999, 2002) transformative…

    9. New Main Ring control system

      SciTech Connect

      Seino, K.; Anderson, L.; Ducar, R.; Franck, A.; Gomilar, J.; Hendricks, B.; Smedinghoff, J.

      1990-03-01

      The Fermilab Main Ring control system has been operational for over sixteen years. Aging and obsolescence of the equipment make the maintenance difficult. Since the advent of the Tevatron, considerable upgrades have been made to the controls of all the Fermilab accelerators except the Main Ring. Modernization of the equipment and standardization of the hardware and software have thus become inevitable. The Tevatron CAMAC serial system has been chosen as a basic foundation in order to make the Main Ring control system compatible with the rest of the accelerator complex. New hardware pieces including intelligent CAMAC modules have been designed to satisfy unique requirements. Fiber optic cable and repeaters have been installed in order to accommodate new channel requirements onto the already saturated communication medium system. 8 refs., 2 figs.

    10. Theoretical Models of Parental HIV Disclosure: A Critical Review

      PubMed Central

      Qiao, Shan; Li, Xiaoming; Stanton, Bonita

      2012-01-01

      This review critically examined three major theoretical models related to parental HIV disclosure (i.e., the Four-Phase Model, the Disclosure Decision Making Model, and the Disclosure Process Model), and the existing studies that could provide empirical support to these models or their components. For each model, we briefly reviewed its theoretical background, described its components and or mechanisms, and discussed its strengths and limitations. The existing empirical studies supported most theoretical components in these models. However, hypotheses related to the mechanisms proposed in the models have not yet tested due to a lack of empirical evidence. This review also synthesized alternative theoretical perspectives and new issues in disclosure research and clinical practice that may challenge the existing models. The current review underscores the importance of including components related to social and cultural contexts in theoretical frameworks, and calls for more adequately designed empirical studies in order to test and refine existing theories and to develop new ones. PMID:22866903

    11. Understanding childbirth practices as an organizational cultural phenomenon: a conceptual framework

      PubMed Central

      2013-01-01

      Understanding the main values and beliefs that might promote humanized birth practices in the specialized hospitals requires articulating the theoretical knowledge of the social and cultural characteristics of the childbirth field and the relations between these and the institution. This paper aims to provide a conceptual framework allowing examination of childbirth practices through the lens of an organizational culture theory. A literature review performed to extrapolate the social and cultural factors contribute to birth practices and the factors likely overlap and mutually reinforce one another, instead of complying with the organizational culture of the birth place. The proposed conceptual framework in this paper examined childbirth patterns as an organizational cultural phenomenon in a highly specialized hospital, in Montreal, Canada. Allaire and Firsirotu’s organizational culture theory served as a guide in the development of the framework. We discussed the application of our conceptual model in understanding the influences of organizational culture components in the humanization of birth practices in the highly specialized hospitals and explained how these components configure both the birth practice and women’s choice in highly specialized hospitals. The proposed framework can be used as a tool for understanding the barriers and facilitating factors encountered birth practices in specialized hospitals. PMID:24215446

    12. Standard Agent Framework 1

      Energy Science and Technology Software Center (ESTSC)

      1999-04-06

      The Standard Agent framework provides an extensible object-oriented development environment suitable for use in both research and applications projects. The SAF provides a means for constructing and customizing multi-agent systems through specialization of standard base classes (architecture-driven framework) and by composition of component classes (data driven framework). The standard agent system is implemented as an extensible object-centerd framework. Four concrete base classes are developed: (1) Standard Agency; (2) Standard Agent; (3) Human Factor, and (4)more » Resources. The object-centered framework developed and utilized provides the best comprimise between generality and flexibility available in agent development systems today.« less

    13. Transformative Approaches to Student Voice: Theoretical Underpinnings, Recalcitrant Realities

      ERIC Educational Resources Information Center

      Fielding, Michael

      2004-01-01

      This article explores some of the theoretical underpinnings of radical approaches to student voice and examines a number of practical issues we need to address if we wish to move towards a more transformative future. The framework within which the notion of voice is explored and critiqued falls primarily into two categories. The first,…

    14. Understanding Literacy: Theoretical Foundations for Research in Media Ecology.

      ERIC Educational Resources Information Center

      Ramos, Lori

      2000-01-01

      Reviews the major scholarship of Harold Innis, Eric Havelock, Marshall McLuhan, Jack Goody, Walter Ong and Elizabeth Eisenstein, as they focused on the development of writing systems, and later, printing. Discusses how their theoretical frameworks are central to understanding media ecology, an emerging field of interdisciplinary study for…

    15. Factors of Motivation in Young Children: Theoretical and Empirical.

      ERIC Educational Resources Information Center

      Adkins, Dorothy C.; Ballif, Bonnie L.

      The construction of Gumpgookies, a test for measuring motivation of young children to achieve in school, is discussed. The test is rooted in a theoretical framework, which conceives of five constituents of motivation to achieve: (1) affective; (2) conceptual; (3) purposive; (4) cognitive; and (5) evaluative. Factor analysis and a type of cluster…

    16. Field-theoretical description of deep inelastic scattering

      SciTech Connect

      Geyer, B.; Robaschik, D.; Wieczorek, E.

      1980-01-01

      The most important theoretical notions concerning deep inelastic scattering are reviewed. Topics discussed are the model-independent approach, which is based on the general principles of quantum field theory, the application of quantum chromodynamics to deep inelastic scattering, approaches based on the quark--parton model, the light cone algebra, and conformal invariance, and also investigations in the framework of perturbation theory.

    17. The Theoretical Foundation for Intercultural Business Communication: A Conceptual Model.

      ERIC Educational Resources Information Center

      Varner, Iris I.

      2000-01-01

      Develops a theoretical framework for intercultural business communication which sets it apart from intercultural communication and international business. Presents a model that discusses the intercultural, business, and communication strategies that are part of intercultural business communication. Examines how past articles in the field fit into…

    18. Families, Geographical Separation, and the Internet: A Theoretical Prospectus.

      ERIC Educational Resources Information Center

      Jaffe, J. Michael; Aidman, Amy

      The perception and acceptance of the Internet as a personal communication channel, and the functional characteristics of the Internet, provide a new means for geographically separated friends and family members to communicate with one another. This paper presents a theoretical framework for the study of family communication and electronic mail. A…

    19. Building a Theoretical Model of Metacognitive Processes in Complex Modeling Activities: A Window into the Development of Students' Metacognitive Abilities

      ERIC Educational Resources Information Center

      Kim, Young Rae

      2013-01-01

      A theoretical model of metacognition in complex modeling activities has been developed based on existing frameworks, by synthesizing the re-conceptualization of metacognition at multiple levels by looking at the three sources that trigger metacognition. Using the theoretical model as a framework, this study was designed to explore how students'…

    20. A comparison of justice frameworks for international research.

      PubMed

      Pratt, Bridget; Loff, Bebe

      2015-07-01

      Justice frameworks have been developed for international research that provide guidance on the selection of research targets, ancillary care, research capacity strengthening, and post-trial benefits. Yet there has been limited comparison of the different frameworks. This paper examines the underlying aims and theoretical bases of three such frameworks--the fair benefits framework, the human development approach and research for health justice--and considers how their aims impact their guidance on the aforementioned four ethical issues. It shows that the frameworks' underlying objectives vary across two dimensions. First, whether they seek to prevent harmful or exploitative international research or to promote international research with health benefits for low and middle-income countries. Second, whether they address justice at the micro level or the macro level. The fair benefits framework focuses on reforming contractual elements in individual international research collaborations to ensure fairness, whereas the other two frameworks aim to connect international research with the reduction of global health inequities. The paper then highlights where there is overlap between the frameworks' requirements and where differences in the strength and content of the obligations they identify arise as a result of their varying objectives and theoretical bases. In doing so, it does not offer a critical comparison of the frameworks but rather seeks to add clarity to current debates on justice and international research by showing how they are positioned relative to one another. PMID:25378552

    1. Theoretical analysis of ARC constriction

      SciTech Connect

      Stoenescu, M.L.; Brooks, A.W.; Smith, T.M.

      1980-12-01

      The physics of the thermionic converter is governed by strong electrode-plasma interactions (emissions surface scattering, charge exchange) and weak interactions (diffusion, radiation) at the maximum interelectrode plasma radius. The physical processes are thus mostly convective in thin sheaths in front of the electrodes and mostly diffusive and radiative in the plasma bulk. The physical boundaries are open boundaries to particle transfer (electrons emitted or absorbed by the electrodes, all particles diffusing through some maximum plasma radius) and to convective, conductive and radiative heat transfer. In a first approximation the thermionic converter may be described by a one-dimensional classical transport theory. The two-dimensional effects may be significant as a result of the sheath sensitivity to radial plasma variations and of the strong sheath-plasma coupling. The current-voltage characteristic of the converter is thus the result of an integrated current density over the collector area for which the boundary conditions at each r determine the regime (ignited/unignited) of the local current density. A current redistribution strongly weighted at small radii (arc constriction) limits the converter performance and opens questions on constriction reduction possibilities. The questions addressed are the followng: (1) what are the main contributors to the loss of current at high voltage in the thermionic converter; and (2) is arc constriction observable theoretically and what are the conditions of its occurrence. The resulting theoretical problem is formulated and results are given. The converter electrical current is estimated directly from the electron and ion particle fluxes based on the spatial distribution of the electron/ion density n, temperatures T/sub e/, T/sub i/, electrical voltage V and on the knowledge of the transport coefficients. (WHK)

    2. Cybersemiotics: a transdisciplinary framework for information studies.

      PubMed

      Brier, S

      1998-04-01

      This paper summarizes recent attempts by this author to create a transdisciplinary, non-Cartesian and non-reductionistic framework for information studies in natural, social, and technological systems. To confront, in a scientific way, the problems of modern information technology where phenomenological man is dealing with socially constructed texts in algorithmically based digital bit-machines we need a theoretical framework spanning from physics over biology and technological design to phenomenological and social production of signification and meaning. I am working with such pragmatic theories as second order cybernetics (coupled with autopolesis theory), Lakoffs biologically oriented cognitive semantics, Peirce's triadic semiotics, and Wittgenstein's pragmatic language game theory. A coherent synthesis of these theories is what the cybersemiotic framework attempts to accomplish. PMID:9648691

    3. A Review of Telehealth Service Implementation Frameworks

      PubMed Central

      van Dyk, Liezl

      2014-01-01

      Despite the potential of telehealth services to increase the quality and accessibility of healthcare, the success rate of such services has been disappointing. The purpose of this paper is to find and compare existing frameworks for the implementation of telehealth services that can contribute to the success rate of future endeavors. After a thorough discussion of these frameworks, this paper outlines the development methodologies in terms of theoretical background, methodology and validation. Finally, the common themes and formats are identified for consideration in future implementation. It was confirmed that a holistic implementation approach is needed, which includes technology, organizational structures, change management, economic feasibility, societal impacts, perceptions, user-friendliness, evaluation and evidence, legislation, policy and governance. Furthermore, there is some scope for scientifically rigorous framework development and validation approaches. PMID:24464237

    4. Theoretical model of critical issues in informed consent in HIV vaccine trials.

      PubMed

      Lewis, Cindi A; Dewhurst, Stephen; McMahon, James M; Bunce, Catherine A; Keefer, Michael C; Alio, Amina P

      2014-01-01

      The informed consent process (ICP) for HIV vaccine trials poses unique challenges and would benefit from improvements to its historically based structure and format. Here, we propose a theoretical framework that provides a basis for systematically evaluating and addressing these challenges. The proposed framework follows a linear pathway, starting with the precondition of voluntariness, three main variables of valid decision-making (competency, provision of information and understanding) and then the consequential outcome of either refusal or consent to participate. The existing literature reveals that culturally appropriate provision of information and resultant understanding by the vaccine trial participant are among the most significant factors influencing the authenticity of valid decision-making, though they may be overridden by other considerations, such as individual altruism, mistrust, and HIV-related stigma. Community collaborations to foster bidirectional transmission of information and more culturally tailored consenting materials, therefore, represent a key opportunity to enhance the ICP. By providing a visual synopsis of the issues most critical to IC effectiveness in a categorical and relational manner, the framework provided here presents HIV vaccine researchers a tool by which the ICP can be more systematically evaluated and consequently improved. PMID:24865892

    5. Theoretical Model of Critical issues in Informed Consent in HIV Vaccine Trials

      PubMed Central

      Lewis, Cindi A.; Dewhurst, Stephen; McMahon, James M.; Bunce, Catherine A.; Keefer, Michael C.; Alio, Amina P.

      2014-01-01

      The informed consent (IC) process for HIV vaccine trials poses unique challenges and would benefit from improvements to its historically-based structure and format. Here, we propose a theoretical framework that provides a basis for systematically evaluating and addressing these challenges. The proposed framework follows a linear pathway, starting with the precondition of voluntariness, three main variables of valid decision-making (competency, provision of information and understanding) and then the consequential outcome of either refusal or consent to participate. The existing literature reveals that culturally appropriate provision of information and resultant understanding by the vaccine trial participant are among the most significant factors influencing the authenticity of valid decision-making, though they may be overridden by other considerations, such as individual altruism, mistrust and HIV-related stigma. Community collaborations to foster bidirectional transmission of information and more culturally tailored consenting materials therefore represent a key opportunity to enhance the informed consent process. By providing a visual synopsis of the issues most critical to IC effectiveness in a categorical and relational manner, the framework provided here presents HIV vaccine researchers a tool by which the informed consent process can be more systematically evaluated and consequently improved. PMID:24865892

    6. GASP- General Aviation Synthesis Program. Volume 1: Main program. Part 1: Theoretical development

      NASA Technical Reports Server (NTRS)

      Hague, D.

      1978-01-01

      The General Aviation synthesis program performs tasks generally associated with aircraft preliminary design and allows an analyst the capability of performing parametric studies in a rapid manner. GASP emphasizes small fixed-wing aircraft employing propulsion systems varying froma single piston engine with fixed pitch propeller through twin turboprop/ turbofan powered business or transport type aircraft. The program, which may be operated from a computer terminal in either the batch or interactive graphic mode, is comprised of modules representing the various technical disciplines integrated into a computational flow which ensures that the interacting effects of design variables are continuously accounted for in the aircraft sizing procedure. The model is a useful tool for comparing configurations, assessing aircraft performance and economics, performing tradeoff and sensitivity studies, and assessing the impact of advanced technologies on aircraft performance and economics.

    7. Main magnetic focus ion source: Basic principles, theoretical predictions and experimental confirmations

      NASA Astrophysics Data System (ADS)

      Ovsyannikov, V. P.; Nefiodov, A. V.

      2016-03-01

      It is proposed to produce highly charged ions in the local potential traps formed by the rippled electron beam in a focusing magnetic field. In this method, extremely high electron current densities can be attained on short length of the ion trap. The design of very compact ion sources of the new generation is presented. The computer simulations predict that for such ions as, for example, Ne8+ and Xe44+, the intensities of about 109 and 106 ions per second, respectively, can be obtained. The experiments with pilot example of the ion source confirm efficiency of the suggested method. The X-ray emission from Ir59+, Xe44+ and Ar16+ ions was detected. The control over depth of the local ion trap is shown to be feasible.

    8. Theoretical approach of the main means of appeals in the European procedural law.

      PubMed

      Petrescu, Oana M

      2015-12-01

      Knowledge and understanting the means of appeals lodged before the courts of the European Union, limited only to the points of law, are very important taking into accout the modality to control a judgment delivered by an inferior court exists since ancient times, being governed among others, by the Larin principle: res judicata pro veritate accipitur. In the following we will examine, in general, the judicial control of the judgments and orders delivered by the General Court and by the Civil Service Tribunal, as a specialized tribunal on civil servant issues, but also the sui generis means of appeals and the extraordinary means of reviews of the judgments and orders. We shall mention that all of them are exercised in accordance with the Rules of Procedure of the European courts and the Statute of the Court of Justice of the European Union. Another aspect to be mentione is that the judjments of the Court of Justice cannot be challenged to another court, as they remain final and irrevocable. PMID:26648542

    9. The EMMA Main Ring Lattice.

      SciTech Connect

      Berg,J.S.

      2008-02-21

      I give a brief introduction to the purpose and goals of the EMMA experiment and describe how they will impact the design of the main EMMA ring. I then describe the mathematical model that is used to describe the EMMA lattice. Finally, I show how the different lattice configurations were obtained and list their parameters.

    10. Main Street in Iowa History.

      ERIC Educational Resources Information Center

      Ruth, Amy, Ed.

      1997-01-01

      This theme issue of "The Goldfinch" focuses on the main streets in Iowa's past. Residential and business patterns are discussed with an analysis of successes and failures. Efforts of young Iowans involved in preservation of a historic town square in their community are described. Activities, fiction selections, and nonfictional accounts of present…

    11. MAINE CONTOUR LINES 500 FEET

      EPA Science Inventory

      MECON500 contains 500 foot contour intervals for Maine, generated from USGS 1:250,000 DEMs. Arcs are coded by elevation. Due to the nature of the source data, the positional accuracy of these contour lines varies from good to poor. Use of these data at scales of greater then 1:2...

    12. MAINE CONTOUR LINES 60 FEET

      EPA Science Inventory

      MECON60 contains contours at 60 foot intervals for the entire state of Maine as generated from USGS 1:250,000 scale digital elevation models using ARC/INFO software. Arcs are coded by elevation. Due to the nature of the source data, the positional accuracy of these contour line...

    13. Theoretical Tools in Modeling Communication and Language Dynamics

      NASA Astrophysics Data System (ADS)

      Loreto, Vittorio

      Statistical physics has proven to be a very fruitful framework to describe phenomena outside the realm of traditional physics. In social phenomena, the basic constituents are not particles but humans and every individual interacts with a limited number of peers, usually negligible compared to the total number of people in the system. In spite of that, human societies are characterized by stunning global regularities that naturally call for a statistical physics approach to social behavior, i.e., the attempt to understand regularities at large scale as collective effects of the interaction among single individuals, considered as relatively simple entities. This is the paradigm of Complex Systems: an assembly of many interacting (and simple) units whose collective behavior is not trivially deducible from the knowledge of the rules governing their mutual interactions. In this chapter we review the main theoretical concepts and tools that physics can borrow to socially-motivated problems. Despite their apparent diversity, most research lines in social dynamics are actually closely connected from the point of view of both the methodologies employed and, more importantly, of the general phenomenological questions, e.g., what are the fundamental interaction mechanisms leading to the emergence of consensus on an issue, a shared culture, a common language or a collective motion?

    14. Measuring user experience in digital gaming: theoretical and methodological issues

      NASA Astrophysics Data System (ADS)

      Takatalo, Jari; Häkkinen, Jukka; Kaistinen, Jyrki; Nyman, Göte

      2007-01-01

      There are innumerable concepts, terms and definitions for user experience. Few of them have a solid empirical foundation. In trying to understand user experience in interactive technologies such as computer games and virtual environments, reliable and valid concepts are needed for measuring relevant user reactions and experiences. Here we present our approach to create both theoretically and methodologically sound methods for quantification of the rich user experience in different digital environments. Our approach is based on the idea that the experience received from a content presented with a specific technology is always a result of a complex psychological interpretation process, which components should be understood. The main aim of our approach is to grasp the complex and multivariate nature of the experience and make it measurable. We will present our two basic measurement frameworks, which have been developed and tested in large data set (n=2182). The 15 measurement scales extracted from these models are applied to digital gaming with a head-mounted display and a table-top display. The results show how it is possible to map between experience, technology variables and the background of the user (e.g., gender). This approach can help to optimize, for example, the contents for specific viewing devices or viewing situations.

    15. Lyoluminescence: A theoretical approach

      NASA Astrophysics Data System (ADS)

      Chattopadhyay, Amit Kr.; Mahapatra, G. S.; Chaudhury, Pinaki

      2000-07-01

      When strongly energized halide or organic crystals are dissolved in a liquid solvent (like water), light is emitted as a result of a recombination process. This phenomenon is called lyoluminescence. The emitted light intensity, called the lyoluminescent intensity, depends on a class of factors like radiation dose, probability of radiative recombination, rate of dissolution in the solvent, etc. Combining some of these numerous effects we develop a nonlinear differential equation and analyze it by a dynamical system analysis as well as by exact numerical integration. The corresponding plot of the theoretical lyoluminescent intensity versus time graph, called the glow curve (Fig. (11)), matches very well with the shape of the experimental curve (Fig. (22)) for a vast range of characteristic values of the controlling parameters.

    16. Theoretical Particle Astrophysics

      SciTech Connect

      Kamionkowski, Marc

      2013-08-07

      Abstract: Theoretical Particle Astrophysics The research carried out under this grant encompassed work on the early Universe, dark matter, and dark energy. We developed CMB probes for primordial baryon inhomogeneities, primordial non-Gaussianity, cosmic birefringence, gravitational lensing by density perturbations and gravitational waves, and departures from statistical isotropy. We studied the detectability of wiggles in the inflation potential in string-inspired inflation models. We studied novel dark-matter candidates and their phenomenology. This work helped advance the DoE's Cosmic Frontier (and also Energy and Intensity Frontiers) by finding synergies between a variety of different experimental efforts, by developing new searches, science targets, and analyses for existing/forthcoming experiments, and by generating ideas for new next-generation experiments.

    17. Reusable rocket engine intelligent control system framework design, phase 2

      NASA Technical Reports Server (NTRS)

      Nemeth, ED; Anderson, Ron; Ols, Joe; Olsasky, Mark

      1991-01-01

      Elements of an advanced functional framework for reusable rocket engine propulsion system control are presented for the Space Shuttle Main Engine (SSME) demonstration case. Functional elements of the baseline functional framework are defined in detail. The SSME failure modes are evaluated and specific failure modes identified for inclusion in the advanced functional framework diagnostic system. Active control of the SSME start transient is investigated, leading to the identification of a promising approach to mitigating start transient excursions. Key elements of the functional framework are simulated and demonstration cases are provided. Finally, the advanced function framework for control of reusable rocket engines is presented.

    18. High frequency variations of the main magnetic field: convergence of observations and theory (Petrus Peregrinus Medal Lecture)

      NASA Astrophysics Data System (ADS)

      Jault, Dominique

      2013-04-01

      Understanding the main magnetic field variations has been hindered by the discrepancy between the periods (from months to years) of the simplest linear wave phenomena and the relatively long time intervals (10 to 100 years) over which magnetic field changes can be confidently monitored. A theoretical description of short-period waves within the Earth's fluid core is at hand. Quasi-geostrophic inertial waves (akin to Rossby waves in the atmosphere) are slightly modified in the presence of magnetic fields and torsional oscillations consist of differential motion between coaxial rigid cylindrical annuli. Torsional oscillations are sensitive to the whole magnetic field that they shear in the course of their propagation. From their modelling, we have thus gained an estimate for the magnetic field strength in the core interior. There is now ongoing work to extend the theoretical framework to longer times. Furthermore, data collected from the Swarm constellation of three satellites to be launched this year by ESA will permit to better separate the internal and external magnetic signals. We may thus dream to detect quasi-geostrophic inertial waves. As the spectral ranges of theoretical models and observations begin to overlap, we can now go beyond the understanding of the magnetic field variations as the juxtaposition of partial models, arranged as a set of nested Matryoshka dolls. This talk will give illustrations for this statement, among which the question of induction in the lower mantle.

    19. LSRA with Shuttle main gear

      NASA Technical Reports Server (NTRS)

      1993-01-01

      A space shuttle landing gear system is visible between the two main landing gear components on this NASA CV-990, modified as a Landing Systems Research Aircraft (LSRA). The space shuttle landing gear test unit, operated by a high-pressure hydraulic system, allowed engineers to assess and document the performance of space shuttle main and nose landing gear systems, tires and wheel assemblies, plus braking and nose wheel steering performance. The series of 155 test missions for the space shuttle program, conducted at NASA's Dryden Flight Research Center, Edwards, California, provided extensive data about the life and endurance of the shuttle tire systems and helped raise the shuttle crosswind landing limits at Kennedy.

    20. The EMMA main ring lattice

      NASA Astrophysics Data System (ADS)

      Berg, J. Scott

      2008-11-01

      The EMMA experiment will study beam dynamics in a linear non-scaling fixed-field alternating gradient (FFAG) accelerator. I give a brief introduction to the purpose and goals of the EMMA experiment and describe how they will impact the design of the main EMMA ring. I then describe the mathematical model that is used to describe the EMMA lattice. Finally, I show how the different lattice configurations were obtained and list their parameters.

    1. Generic Overlay Framework

      Energy Science and Technology Software Center (ESTSC)

      2005-09-01

      This software provides a framework for building application layter overlay networks. It includes example overlays that can be used without modification. Also provided are example multicast and routing protocols that can be used with the overlays.

    2. Theoretical analysis of signal-to-noise ratios for transient evoked otoacoustic emission recordings.

      PubMed

      Lineton, Ben

      2013-09-01

      Recordings of transient-evoked otoacoustic emissions (TEOAEs) suffer from two main sources of contamination: Random noise and the stimulus artifact. The stimulus artifact can be substantially reduced by using a derived non-linear recording paradigm. Three such paradigms are analyzed, called here the level derived non-linear (LDNL), the double-evoked (DE), and the rate derived non-linear (RDNL) paradigms. While these methods successfully reduce the stimulus artifact, they lead to an increase in contamination by random noise. In this study, the signal-to-noise ratio (SNR) achievable by these three paradigms is compared using a common theoretical framework. This analysis also allows the optimization of the parameters of the RDNL paradigm to achieve the maximum SNR. Calculations based on the analysis with typical parameters used in practice suggest that when ranked in terms of their SNR for a given averaging time, RDNL performs best followed by the LDNL and DE paradigms. PMID:23967942

    3. Information Theoretic Shape Matching.

      PubMed

      Hasanbelliu, Erion; Giraldo, Luis Sanchez; Príncipe, José C

      2014-12-01

      In this paper, we describe two related algorithms that provide both rigid and non-rigid point set registration with different computational complexity and accuracy. The first algorithm utilizes a nonlinear similarity measure known as correntropy. The measure combines second and high order moments in its decision statistic showing improvements especially in the presence of impulsive noise. The algorithm assumes that the correspondence between the point sets is known, which is determined with the surprise metric. The second algorithm mitigates the need to establish a correspondence by representing the point sets as probability density functions (PDF). The registration problem is then treated as a distribution alignment. The method utilizes the Cauchy-Schwarz divergence to measure the similarity/distance between the point sets and recover the spatial transformation function needed to register them. Both algorithms utilize information theoretic descriptors; however, correntropy works at the realizations level, whereas Cauchy-Schwarz divergence works at the PDF level. This allows correntropy to be less computationally expensive, and for correct correspondence, more accurate. The two algorithms are robust against noise and outliers and perform well under varying levels of distortion. They outperform several well-known and state-of-the-art methods for point set registration. PMID:26353150

    4. A thermodynamical framework for chemically reacting systems

      NASA Astrophysics Data System (ADS)

      Kannan, K.; Rajagopal, K. R.

      2011-04-01

      In this paper, we develop a thermodynamic framework that is capable of describing the response of viscoelastic materials that are undergoing chemical reactions that takes into account stoichiometry. Of course, as a special sub-case, we can also describe the response of elastic materials that undergo chemical reactions. The study generalizes the framework developed by Rajagopal and co-workers to study the response of a disparate class of bodies undergoing entropy producing processes. One of the quintessential feature of this framework is that the second law of thermodynamics is formulated by introducing Gibbs' potential, which is the natural way to study problems involving chemical reactions. The Gibbs potential-based formulation also naturally leads to implicit constitutive equations for the stress tensor. Another feature of the framework is that the constraints due to stoichiometry can also be taken into account in a consistent manner. The assumption of maximization of the rate of entropy production due to dissipation, heat conduction, and chemical reactions is invoked to determine an equation for the evolution of the natural configuration ? p( t)( B), the heat flux vector and a novel set of equations for the evolution of the concentration of the chemical constituents. To determine the efficacy of the framework with regard to chemical reactions, those occurring during vulcanization, a challenging set of chemical reactions, are chosen. More than one type of reaction mechanism is considered and the theoretically predicted distribution of mono, di and polysulfidic cross-links agree reasonably well with available experimental data.

    5. A framework for comparing different image segmentation methods and its use in studying equivalences between level set and fuzzy connectedness frameworks

      PubMed Central

      Ciesielski, Krzysztof Chris; Udupa, Jayaram K.

      2011-01-01

      In the current vast image segmentation literature, there seems to be considerable redundancy among algorithms, while there is a serious lack of methods that would allow their theoretical comparison to establish their similarity, equivalence, or distinctness. In this paper, we make an attempt to fill this gap. To accomplish this goal, we argue that: (1) every digital segmentation algorithm A should have a well defined continuous counterpart MA, referred to as its model, which constitutes an asymptotic of A when image resolution goes to infinity; (2) the equality of two such models MA and MA? establishes a theoretical (asymptotic) equivalence of their digital counterparts A and A?. Such a comparison is of full theoretical value only when, for each involved algorithm A, its model MA is proved to be an asymptotic of A. So far, such proofs do not appear anywhere in the literature, even in the case of algorithms introduced as digitizations of continuous models, like level set segmentation algorithms. The main goal of this article is to explore a line of investigation for formally pairing the digital segmentation algorithms with their asymptotic models, justifying such relations with mathematical proofs, and using the results to compare the segmentation algorithms in this general theoretical framework. As a first step towards this general goal, we prove here that the gradient based thresholding model M? is the asymptotic for the fuzzy connectedness Udupa and Samarasekera segmentation algorithm used with gradient based affinity A?. We also argue that, in a sense, M? is the asymptotic for the original front propagation level set algorithm of Malladi, Sethian, and Vemuri, thus establishing a theoretical equivalence between these two specific algorithms. Experimental evidence of this last equivalence is also provided. PMID:21442014

    6. Field-Theoretic Simulations

      NASA Astrophysics Data System (ADS)

      Ganesan, Venkat; Fredrickson, Glenn H.

      The science and engineering of materials is entering a new era of so-called "designer materials", wherein, based upon the properties required for a particular application, a material is designed by exploiting the self-assembly of appropriately chosen molecular constituents [1]. The desirable and marketable properties of such materials, which include plastic alloys, block and graft copolymers, and polyelectrolyte solutions, complexes, and gels, depend critically on the ability to control and manipulate morphology by adjusting a combination of molecular and macroscopic variables. For example, styrenebutadiene block copolymers can be devised that serve either as rigid, tough, transparent thermoplastics or as soft, flexible, thermoplastic elastomers, by appropriate control of copolymer architecture and styrene/butadiene ratio. In this case, the property profiles are intimately connected to the extent and type of nanoscale self-assembly that is established within the material. One of the main challenges confronting the successful design of nano-structured polymers is the development of a basic understanding of the relationship between the molecular details of the polymer formulation and the morphology that is achieved. Unfortunately, such relationships are still mainly determined by trial and error experimentation. A purely experimental-based program in pursuit of this objective proves cumbersome — primarily, due to the broad parameter space accessible at the time of synthesis and formulation. Consequently, there is a significant motivation for the development of computational tools that can enable a rational exploration of the parameter space.

    7. Testing modeling frameworks

      NASA Astrophysics Data System (ADS)

      Hill, Mary; Ye, Ming; Foglia, Laura; Lu, Dan

      2015-04-01

      Modeling frameworks include many ideas about, for example, how to parameterize models, conduct sensitivity analysis (including identifying observations and parameters important to calibration and prediction), quantify uncertainty, and so on. Of concern in this talk is meaningful testing of how ideas proposed for any modeling framework perform. The design of meaningful tests depends on the aspect of the framework being tested and the timing of system dynamics. Consider a situation in which the aspect being tested is prediction accuracy and the quantities of concern are readily measured and change quickly, such as for precipitation, floods, or hurricanes. In such cases meaningful tests involve comparing simulated and measured values and tests can be conducted daily, hourly or even more frequently. Though often challenged by measurement difficulties, this remains the simplest circumstance for conducting meaningful tests of modeling frameworks. If measurements are not readily available and(or) the system responds to changes over decades or centuries, as generally occurs for climate change, saltwater intrusion of groundwater systems, and dewatering of aquifers, prediction accuracy needs to be evaluated in other ways. Often these require high performance computing. For example, complex and simple models can be compared or cross-validation experiments can be conducted. Both can require massive computational resources for any but the simplest of problems. Testing other aspects of a modeling framework can require different types of tests. For example, testing methods of identifying observations or parameters important to model calibration or predictions might entail evaluation of many circumstances for methods that are themselves commonly computationally demanding. Again, high performance computing is needed even when the goal is to include computationally frugal methods in the modeling framework. In this talk we discuss the importance of such testing, stress the need to design and implement tests when any modeling framework is developed, and provide examples of tests from several recent publications.

    8. Adventures in theoretical astrophysics

      NASA Astrophysics Data System (ADS)

      Farmer, Alison Jane

      This thesis is a tour of topics in theoretical astrophysics, unified by their diversity and their pursuit of physical understanding of astrophysical phenomena. In the first chapter, we raise the possibility of the detection of white dwarfs in transit surveys for extrasolar Earths, and discuss the peculiarities of detecting these more massive objects. A population synthesis calculation of the gravitational wave background from extragalactic binary stars is then presented. In this study, we establish a firm understanding of the uncertainties in such a calculation and provide a valuable reference for planning the Laser Interferometer Space Antenna mission. The long-established problem of cosmic ray confinement to the Galaxy is addressed in another chapter. We introduce a new wave damping mechanism, due to the presence of background turbulence, that prevents the confinement of cosmic rays by the resonant streaming instability. We also investigate the spokes in Saturn's B ring, an electrodynamic mystery that is being illuminated by new data sent back from the Cassini spacecraft. In particular, we present assessments of the presence of charged dust near the rings, and the size of currents and electric fields in the ring system. We make inferences from the Cassini discovery of oxygen ions above the rings. In addition, the previous leading theory for spoke formation is demonstrated to be unphysical. In the final chapter, we explain the wayward motions of Prometheus and Pandora, two small moons of Saturn. Previously found to be chaotic as a result of mutual interactions, we account for their behavior by analogy with a parametric pendulum. We caution that this behavior may soon enter a new regime.

    9. Space shuttle main engine controller

      NASA Technical Reports Server (NTRS)

      Mattox, R. M.; White, J. B.

      1981-01-01

      A technical description of the space shuttle main engine controller, which provides engine checkout prior to launch, engine control and monitoring during launch, and engine safety and monitoring in orbit, is presented. Each of the major controller subassemblies, the central processing unit, the computer interface electronics, the input electronics, the output electronics, and the power supplies are described and discussed in detail along with engine and orbiter interfaces and operational requirements. The controller represents a unique application of digital concepts, techniques, and technology in monitoring, managing, and controlling a high performance rocket engine propulsion system. The operational requirements placed on the controller, the extremely harsh operating environment to which it is exposed, and the reliability demanded, result in the most complex and rugged digital system ever designed, fabricated, and flown.

    10. The Main Aeromonas Pathogenic Factors

      PubMed Central

      Tomás, J. M.

      2012-01-01

      The members of the Aeromonas genus are ubiquitous, water-borne bacteria. They have been isolated from marine waters, rivers, lakes, swamps, sediments, chlorine water, water distribution systems, drinking water and residual waters; different types of food, such as meat, fish, seafood, vegetables, and processed foods. Aeromonas strains are predominantly pathogenic to poikilothermic animals, and the mesophilic strains are emerging as important pathogens in humans, causing a variety of extraintestinal and systemic infections as well as gastrointestinal infections. The most commonly described disease caused by Aeromonas is the gastroenteritis; however, no adequate animal model is available to reproduce this illness caused by Aeromonas. The main pathogenic factors associated with Aeromonas are: surface polysaccharides (capsule, lipopolysaccharide, and glucan), S-layers, iron-binding systems, exotoxins and extracellular enzymes, secretion systems, fimbriae and other nonfilamentous adhesins, motility and flagella. PMID:23724321

    11. General Aviation Data Framework

      NASA Technical Reports Server (NTRS)

      Blount, Elaine M.; Chung, Victoria I.

      2006-01-01

      The Flight Research Services Directorate at the NASA Langley Research Center (LaRC) provides development and operations services associated with three general aviation (GA) aircraft used for research experiments. The GA aircraft includes a Cessna 206X Stationair, a Lancair Colombia 300X, and a Cirrus SR22X. Since 2004, the GA Data Framework software was designed and implemented to gather data from a varying set of hardware and software sources as well as enable transfer of the data to other computers or devices. The key requirements for the GA Data Framework software include platform independence, the ability to reuse the framework for different projects without changing the framework code, graphics display capabilities, and the ability to vary the interfaces and their performance. Data received from the various devices is stored in shared memory. This paper concentrates on the object oriented software design patterns within the General Aviation Data Framework, and how they enable the construction of project specific software without changing the base classes. The issues of platform independence and multi-threading which enable interfaces to run at different frame rates are also discussed in this paper.

    12. Puzzling Snowballs: Main Belt Comets

      NASA Astrophysics Data System (ADS)

      Yang, Bin; Meech, Karen

      2015-03-01

      Main belt comets (MBCs) are a class of newly discovered objects that exhibit comet-like appearances and yet are dynamically indistinguishable from ordinary main belt asteroids. The measured size and albedo of MBCs are similar to those of classical comets. At present, six MBCs have been discovered, namely 133P/Elst-Pizarro, 176P/LINEAR, 238P/Read, P/2008 R1, P/La Sagra and P/2006 VW139. The total number of active MBCs is estimated to be at the level of a few hundreds (Hsieh & Jewitt, 2006). Several explanations for the activity of MBCs have been suggested. These include impact ejection, sublimation and rotational instability. However, since renewed activity has been observed in 133P and 238P at successive perihelion passages, the most likely explanation may be a thermally-driven process - e.g sublimation of exposed surface ice. Although the proximity of MBCs to the Sun (r ~ 3 AU) makes the survival of surface ice improbable, thermal models have shown that water ice is thermally stable under a regolith layer a few meters thick. The study of MBCs has recently been complicated by the discoveries of two asteroid collisional events (P/2010 A2 (LINEAR) and (596) Scheila) in 2010, where comet-like dust coma/tail have been attributed to recent impacts. If MBCs are indeed icy, they represent the closest and the third established reservoir of comets (after the Oort cloud and the Kuiper belt). As such, they may have been an important source of water for the Earth's oceans. I will review the current state of MBC studies, present the latest observational results and discuss possible mechanisms that could produce the observed activity. I will also talk about current and future space missions that are dedicated or closely related to MBC studies.

    13. Some New Theoretical Issues in Systems Thinking Relevant for Modelling Corporate Learning

      ERIC Educational Resources Information Center

      Minati, Gianfranco

      2007-01-01

      Purpose: The purpose of this paper is to describe fundamental concepts and theoretical challenges with regard to systems, and to build on these in proposing new theoretical frameworks relevant to learning, for example in so-called learning organizations. Design/methodology/approach: The paper focuses on some crucial fundamental aspects introduced…

    14. "The Integrity and Obstinacy of Intellectual Creations": Jurgen Habermas and Librarianship's Theoretical Literature

      ERIC Educational Resources Information Center

      Buschman, John

      2006-01-01

      Librarianship and library and information science (LIS) have long struggled with an ongoing lack of a theoretical and epistemological basis. There have been renewed efforts to explore various theoretical and philosophical positions and their meaning for librarianship and LIS research. This article explores the framework that Jurgen Habermas offers…

    15. UCLA Parallel PIC Framework

      NASA Astrophysics Data System (ADS)

      Decyk, Viktor K.; Norton, Charles D.

      2004-12-01

      The UCLA Parallel PIC Framework (UPIC) has been developed to provide trusted components for the rapid construction of new, parallel Particle-in-Cell (PIC) codes. The Framework uses object-based ideas in Fortran95, and is designed to provide support for various kinds of PIC codes on various kinds of hardware. The focus is on student programmers. The Framework supports multiple numerical methods, different physics approximations, different numerical optimizations and implementations for different hardware. It is designed with "defensive" programming in mind, meaning that it contains many error checks and debugging helps. Above all, it is designed to hide the complexity of parallel processing. It is currently being used in a number of new Parallel PIC codes.

    16. Unsupervised active learning based on hierarchical graph-theoretic clustering.

      PubMed

      Hu, Weiming; Hu, Wei; Xie, Nianhua; Maybank, Steve

      2009-10-01

      Most existing active learning approaches are supervised. Supervised active learning has the following problems: inefficiency in dealing with the semantic gap between the distribution of samples in the feature space and their labels, lack of ability in selecting new samples that belong to new categories that have not yet appeared in the training samples, and lack of adaptability to changes in the semantic interpretation of sample categories. To tackle these problems, we propose an unsupervised active learning framework based on hierarchical graph-theoretic clustering. In the framework, two promising graph-theoretic clustering algorithms, namely, dominant-set clustering and spectral clustering, are combined in a hierarchical fashion. Our framework has some advantages, such as ease of implementation, flexibility in architecture, and adaptability to changes in the labeling. Evaluations on data sets for network intrusion detection, image classification, and video classification have demonstrated that our active learning framework can effectively reduce the workload of manual classification while maintaining a high accuracy of automatic classification. It is shown that, overall, our framework outperforms the support-vector-machine-based supervised active learning, particularly in terms of dealing much more efficiently with new samples whose categories have not yet appeared in the training samples. PMID:19336318

    17. A Framework for WWW Query Processing

      NASA Technical Reports Server (NTRS)

      Wu, Binghui Helen; Wharton, Stephen (Technical Monitor)

      2000-01-01

      Query processing is the most common operation in a DBMS. Sophisticated query processing has been mainly targeted at a single enterprise environment providing centralized control over data and metadata. Submitting queries by anonymous users on the web is different in such a way that load balancing or DBMS' accessing control becomes the key issue. This paper provides a solution by introducing a framework for WWW query processing. The success of this framework lies in the utilization of query optimization techniques and the ontological approach. This methodology has proved to be cost effective at the NASA Goddard Space Flight Center Distributed Active Archive Center (GDAAC).

    18. Multimedia content description framework

      NASA Technical Reports Server (NTRS)

      Bergman, Lawrence David (Inventor); Kim, Michelle Yoonk Yung (Inventor); Li, Chung-Sheng (Inventor); Mohan, Rakesh (Inventor); Smith, John Richard (Inventor)

      2003-01-01

      A framework is provided for describing multimedia content and a system in which a plurality of multimedia storage devices employing the content description methods of the present invention can interoperate. In accordance with one form of the present invention, the content description framework is a description scheme (DS) for describing streams or aggregations of multimedia objects, which may comprise audio, images, video, text, time series, and various other modalities. This description scheme can accommodate an essentially limitless number of descriptors in terms of features, semantics or metadata, and facilitate content-based search, index, and retrieval, among other capabilities, for both streamed or aggregated multimedia objects.

    19. Healthcare Information Framework.

      PubMed

      Saranummi, N; Demeester, M; Fernandez Perez de Talens, A; Harrington, J; Heimly, V; de la Riva Grandal, J M; Taylor, J

      1995-04-01

      CEN committee TC 251 Medical Informatics, has set up a project team charged with producing a European pre-standard ENV on Healthcare Information Framework (HIF). The HIF is based on abstraction from a specific information system architecture to a reference architecture and further to a conceptual architectural framework based on serving open, distributed and heterogeneous healthcare enterprises. To specify the suitable healthcare information system architecture modelling of the healthcare enterprise is required. As there is no one method serving all needs, the HIF gives guidance on what aspects to look at in selecting a suitable modelling method. It is expected that the work will be completed by early 1995. PMID:7601549

    20. Main memory unit. [hybrid computers

      NASA Technical Reports Server (NTRS)

      1975-01-01

      The development of a main memory unit (MMU) for the space ultrareliable module computer (SUMC) model HTC is discussed. The design, fabrication, and test of basic memory modules (BMM) which were to be used in the design and construction of the MMU are described. The BMM was designed from state-of-the-art technologies which included large scale integration devices mounted and interconnected on a substrate to form a functional module to be utilized in the MMU development. A SUMC memory system design study is discussed which addressed itself to the BMM design and analysis to be conducted to determine the most efficient organization of the BMM in order to establish such modularity features as: word length expandability without redesign, high reliability, and fault tolerance. One MMU was designed, fabricated, tested, and delivered which will be electrical and mechanically compatible with the hybrid technology computer (HTC) model of the SUMC family of computers. The MMU will contain a storage capacity of 8196 36 bit words which includes a parity bit for each 8 bit byte of data.

    1. Main Dangers of Our Times.

      NASA Astrophysics Data System (ADS)

      Synek, Miroslav

      2003-03-01

      Terrorism and threatening dictatorships are the main, man-made, dangers of our times. They are run by master demagogues, or, brain-washing manipulators. ----- Our next step in coping with terrorism is to counter master demagoguery. Therefore, supporting EDUCATION that would emphasize the most unifying (and the least controversial), yet, BASIC CIVIC RESPECT for lives of people in a civilian human society, is a priority everywhere on our planet. ----- At the same time we start facing mostly small, threatening, dictatorships, capable of producing weapons of mass destruction. Therefore, we have to try to contribute to developing systems of FREE ELECTIONS, controlling weapons of mass destruction, wherever such dangers exist. ----- In a foreseeable future, unfortunately, we are facing a danger even by orders of magnitude greater. We are facing a possibility of a mass-produced heavy accumulation of inter-continental nuclear missiles, on a computerized "push-button" control, by a very powerful (and, quite possibly, miscalculating, or, suicidal) dictator, dangerous to the very existence of humanity on our planet. Therefore, it is a historical urgency that such a technological power be under the control by a government of the people, by the people and for the people, based on a sufficiently reliable system of FREE ELECTIONS, wherever, on our planet, such a potential danger may originate.

    2. Theoretical actinide molecular science.

      PubMed

      Schreckenbach, Georg; Shamov, Grigory A

      2010-01-19

      Interest in the chemistry of the early actinide elements (notably uranium through americium) usually results either from the nuclear waste problem or the unique chemistry of these elements that result from 5f contributions to bonding. Computational actinide chemistry provides one useful tool for studying these processes. Theoretical actinide chemistry is challenging because three principal axes of approximation have to be optimized. These are the model chemistry (the choice of approximate electron-electron correlation method and basis sets), the approximate relativistic method, and a method for modeling solvent (condensed phase) effects. In this Account, we arrange these approximations in a three-dimensional diagram, implying that they are relatively independent of each other. A fourth level of approximation concerns the choice of suitable models for situations too complex to treat in their entirety. We discuss test cases for each of these approximations. Gas-phase data for uranium fluorides and oxofluorides such as UF(6) and UO(2)F(2) show that GGA functionals provide accurate geometries and frequencies while hybrid density functional theory (DFT) functionals are superior for energetics. MP2 is seen to be somewhat erratic for this set of compounds, and CCSD(T) gives the most accurate results. Three different relativistic methods, small-core effective core potentials (SC-ECP), ZORA, and all-electron scalar, provide comparable results. The older large-core ECP (LC-ECP) approach is consistently worse and should not be used. We confirmed these conclusions through studies of the actinyl aquo complexes [AnO(2)(OH(2))(5)](n+), (An = U, Np, or Pu and n = 1 or 2) that are also used to test solvation models. As long as the first coordination sphere of the metal is included explicitly, continuum solvation models are reliable, and we found no clear advantage for the (costly) explicit treatment of the second coordination sphere. Spin-orbit effects must be included to reproduce the correct trend in An(VI)/An(V) reduction potentials. We propose a multistep mechanism for the experimentally observed oxygen exchange of UO(2)(2+) cations in highly alkaline solutions present in tank wastes. This process involves an equilibrium between [UO(2)(OH)(4)](2-) and [UO(2)(OH)(5)](3-), followed by formation of the stable [UO(3)(OH)(3)](3-) intermediate that forms from [UO(2)(OH)(5)](3-) through intramolecular water elimination. The [UO(3)(OH)(3)](3-) intermediate facilitates oxygen exchange through proton shuttling. We explain the experimentally observed stabilization of the pentavalent oxidation state of actinyl ions by macrocyclic ligands (such as 18-crown-6) as an effect of solvation: the large macrocycle screens the positive charge of the ion from the polarizable solvent. Alkyl-substituted isoamethyrin complexes are bent despite being aromatic because of steric factors, rather than fit/misfit criteria regarding the actinyl ion. By application of an efficient DFT code, actinide molecules with more than 100 atoms can now be studied routinely. "Real" chemical questions can be answered as long as we take great care to apply methods that are accurate with respect to the three axes of approximation described above. While the exclusive focus of this Account has been on the early actinide elements, these conclusions also apply elsewhere in the periodic table. PMID:19719099

    3. Skutterudite: Theoretical and Experimental Study

      NASA Astrophysics Data System (ADS)

      Nieroda, P.; Kutorasinski, K.; Tobola, J.; Wojciechowski, K. T.

      2014-06-01

      Korringa-Kohn-Rostoker coherent potential approximation (KKR-CPA) calculations of Ag-doped CoSb3 point to the presence of either an extra sharp peak of s-symmetry Ag density of states near the valence-band edge when filling the void (2 a) or to conventional p-type doping when substituting Sb site (24 g). These results suggest a resonant-like impurity level in the former or nearly rigid-band behavior in the latter. To confirm the theoretical predictions, a series of samples with nominal composition Co8Sb24:Ag x ( x = 0, 0.1, 0.3, 0.4, 0.5) were prepared. Structural and phase composition analyses were carried out by x-ray diffraction, scanning electron microscopy, and scanning thermoelectric microprobe. Investigations of the influence of Ag impurity on the electrical conductivity and Seebeck coefficient were performed over the temperature range from 300 K to 560 K. It was found that doping CoSb3 with Ag leads to an increase of the thermoelectric power factor ? 2 ? in the temperature range from 300 K to 475 K of about an order of magnitude for all doped samples. However, electron probe microanalysis revealed accumulation of Ag mainly in grain boundaries while the presence of Ag in CoSb3 crystallites was not confirmed. This observation corroborates the results of KKR-CPA calculations concerning the formation energy of the Ag x Co4Sb12 system, which is much lower than values calculated for A x Co4Sb12 ( A = Ca, Ba).

    4. Some theoretical issues on computer simulations

      SciTech Connect

      Barrett, C.L.; Reidys, C.M.

      1998-02-01

      The subject of this paper is the development of mathematical foundations for a theory of simulation. Sequentially updated cellular automata (sCA) over arbitrary graphs are employed as a paradigmatic framework. In the development of the theory, the authors focus on the properties of causal dependencies among local mappings in a simulation. The main object of and study is the mapping between a graph representing the dependencies among entities of a simulation and a representing the equivalence classes of systems obtained by all possible updates.

    5. A general framework and review of scatter correction methods in cone beam CT. Part 2: Scatter estimation approaches

      SciTech Connect

      Ruehrnschopf and, Ernst-Peter; Klingenbeck, Klaus

      2011-09-15

      The main components of scatter correction procedures are scatter estimation and a scatter compensation algorithm. This paper completes a previous paper where a general framework for scatter compensation was presented under the prerequisite that a scatter estimation method is already available. In the current paper, the authors give a systematic review of the variety of scatter estimation approaches. Scatter estimation methods are based on measurements, mathematical-physical models, or combinations of both. For completeness they present an overview of measurement-based methods, but the main topic is the theoretically more demanding models, as analytical, Monte-Carlo, and hybrid models. Further classifications are 3D image-based and 2D projection-based approaches. The authors present a system-theoretic framework, which allows to proceed top-down from a general 3D formulation, by successive approximations, to efficient 2D approaches. A widely useful method is the beam-scatter-kernel superposition approach. Together with the review of standard methods, the authors discuss their limitations and how to take into account the issues of object dependency, spatial variance, deformation of scatter kernels, external and internal absorbers. Open questions for further investigations are indicated. Finally, the authors refer on some special issues and applications, such as bow-tie filter, offset detector, truncated data, and dual-source CT.

    6. Theoretical horizontal-branch evolution

      NASA Technical Reports Server (NTRS)

      Sweigart, Allen V.

      1987-01-01

      The general features of the theoretical evolution of canonical horizontal-branch (HB) stars are briefly reviewed with specific emphasis on the track morphology in the HR diagram and the determination of the globular cluster helium abundance. The observational evidence for the occurrence of semiconvection is discussed together with some remaining theoretical uncertainty.

    7. Exploring the Science Framework

      ERIC Educational Resources Information Center

      Bell, Philip; Bricker, Leah; Tzou, Carrie; Lee, Tiffany; Van Horne, Katie

      2012-01-01

      The National Research Council's recent publication "A Framework for K-12 Science Education: Practices, Crosscutting Concepts, and Core Ideas" (NRC 2011), which is the foundation for the Next Generation Science Standards now being developed, places unprecedented focus on the practices involved in doing scientific and engineering work. In an effort…

    8. Exploring the Science Framework

      ERIC Educational Resources Information Center

      Bell, Philip; Bricker, Leah; Tzou, Carrie; Lee, Tiffany; Van Horne, Katie

      2012-01-01

      The National Research Council's recent publication "A Framework for K-12 Science Education: Practices, Crosscutting Concepts, and Core Ideas" (NRC 2011), which is the foundation for the Next Generation Science Standards now being developed, places unprecedented focus on the practices involved in doing scientific and engineering work. In an effort…

    9. Exploring the Science Framework

      ERIC Educational Resources Information Center

      Mayes, Robert; Koballa, Thomas R., Jr.

      2012-01-01

      The vision for science education set forth in "A Framework for K-12 Science Education" (NRC 2012) makes it clear that for today's students to become the scientifically literate citizens of tomorrow their educational experiences must help them become mathematically proficient. "The focus here is on important practices, such as modeling, developing…

    10. Exploring the Science Framework

      ERIC Educational Resources Information Center

      Mayes, Robert; Koballa, Thomas R., Jr.

      2012-01-01

      The vision for science education set forth in "A Framework for K-12 Science Education" (NRC 2012) makes it clear that for today's students to become the scientifically literate citizens of tomorrow, their educational experiences must help them become mathematically proficient. "The focus here is on important practices, such as modeling, developing…

    11. Facilitating the Exploratorium Framework.

      ERIC Educational Resources Information Center

      Klages, Ellen

      This document describes the Exploratorium Framework project which is a model initiative demonstrating the vital role science museums play in science education reform. Contents include: (1) "The Four Thematic Exhibit Experiments (An Overview)"; (2) "Themes (Looking at the World through Theme-Colored Glasses)"; (3) "Creating an Environment (Don't…

    12. DCPS Effective Schools Framework

      ERIC Educational Resources Information Center

      District of Columbia Public Schools, 2009

      2009-01-01

      DCPS is committed to providing "all" students with the caliber of education they deserve. The goal of the DCPS Effective Schools Framework is to ensure that every child, in every classroom, has access to a high-quality and engaging standards-based instructional program, and that all school supports are aligned to support teaching and learning. The…

    13. Futurism: Framework for Composition.

      ERIC Educational Resources Information Center

      Keroack, Elizabeth Carros; Marquis, Leah Keating

      Noting that the study of the future has been neglected within the language arts framework, this paper proposes a curriculum unit that uses such study as a vehicle to develop composition skills. The paper provides the following information: the general objectives of the unit; evaluation methods; general humanistic themes to be studied; materials;…

    14. Heterochromatin and complexity: a theoretical approach.

      PubMed

      Spinelli, Gino

      2003-10-01

      Heterochromatin represents 30% of eukaryotic genome in Drosophila and 15% in humans. Despite extensive research spanning many decades, its evolutionary significance, as well as the forces that guarantee its maintenance, are still elusive. Many theoretical and experimental approaches have led researchers to propose several conceptual frameworks to elucidate the nature of this huge mysterious genetic material and its spreading in all eukaryotic genomes. "Junk DNA" as well as "selfish genetic material" are two examples of such attempts, but several lines of evidence suggest that such explanations are incomplete. In fact, if the selfish DNA hypothesis does not explain the mapping of genetic functions in heterochromatin, then the junk DNA hypothesis is incomplete in describing both emergence of genetic functions and their maintenance in the eukaryotic heterochromatin. Recent developments in the physics of complex systems and mathematical concepts such as fractals provide new conceptual clues to answer several basic questions concerning the emergence of heterochromatin in eukaryotic genomes, its evolutionary significance, the forces that guarantee its maintenance, and its peculiar behavior in the eukaryotic cell. The aim of this paper is to provide a new theoretical framework for the heterochromatin, considering such genetic material in physical terms as a complex adaptive system. We apply some computer calculations to demonstrate the nonlinearity of the flux of genetic information along the phylogenic tree. Fractal dimensions of representative heterochromatic sequences are provided. A theory is proposed in which heterochromatin is considered a system that evolves in a self-organized manner at the edge of cellular and environmental chaos. PMID:14523268

    15. Virtual Mission Operation Framework (VMOF)

      NASA Technical Reports Server (NTRS)

      Lee, Meemong; Weidner, Richard J.

      2004-01-01

      The Virtual Mission Operation Framework (VMOF) is one of the project lifecycle engineering process improvement efforts initiated by the institutional technology infrastructure program at JPL. The VMOF is composed of three frameworks: a model integration framework, a simulation framework, and a visualization framework. The model integration framework interfaces with spacecraft system design, mission design, and structure design. The simulation framework interfaces with the operation scenario design, environmental phenomena science, and science payload system design. The visualization framework interfaces with the flight system testbed, the ground system, and the science analysis. The three frameworks of the VMOF collaborate to create a comprehensive virtual mission operation that enables a "validation-in-the-loop" system design process and lifecycle-continuous science-return validation.This paper discusses the technical approaches for each framework implementation, challenges and approaches involved in streamlining mission information access, and on-going activities toward enabling Model-Based Engineering Design in a collaborative distributed environment.

    16. Sci-Vis Framework

      SciTech Connect

      2015-03-11

      SVF is a full featured OpenGL 3d framework that allows for rapid creation of complex visualizations. The SVF framework handles much of the lifecycle and complex tasks required for a 3d visualization. Unlike a game framework SVF was designed to use fewer resources, work well in a windowed environment, and only render when necessary. The scene also takes advantage of multiple threads to free up the UI thread as much as possible. Shapes (actors) in the scene are created by adding or removing functionality (through support objects) during runtime. This allows a highly flexible and dynamic means of creating highly complex actors without the code complexity (it also helps overcome the lack of multiple inheritance in Java.) All classes are highly customizable and there are abstract classes which are intended to be subclassed to allow a developer to create more complex and highly performant actors. There are multiple demos included in the framework to help the developer get started and shows off nearly all of the functionality. Some simple shapes (actors) are already created for you such as text, bordered text, radial text, text area, complex paths, NURBS paths, cube, disk, grid, plane, geometric shapes, and volumetric area. It also comes with various camera types for viewing that can be dragged, zoomed, and rotated. Picking or selecting items in the scene can be accomplished in various ways depending on your needs (raycasting or color picking.) The framework currently has functionality for tooltips, animation, actor pools, color gradients, 2d physics, text, 1d/2d/3d textures, children, blending, clipping planes, view frustum culling, custom shaders, and custom actor states

    17. Sci-Vis Framework

      Energy Science and Technology Software Center (ESTSC)

      2015-03-11

      SVF is a full featured OpenGL 3d framework that allows for rapid creation of complex visualizations. The SVF framework handles much of the lifecycle and complex tasks required for a 3d visualization. Unlike a game framework SVF was designed to use fewer resources, work well in a windowed environment, and only render when necessary. The scene also takes advantage of multiple threads to free up the UI thread as much as possible. Shapes (actors) inmore » the scene are created by adding or removing functionality (through support objects) during runtime. This allows a highly flexible and dynamic means of creating highly complex actors without the code complexity (it also helps overcome the lack of multiple inheritance in Java.) All classes are highly customizable and there are abstract classes which are intended to be subclassed to allow a developer to create more complex and highly performant actors. There are multiple demos included in the framework to help the developer get started and shows off nearly all of the functionality. Some simple shapes (actors) are already created for you such as text, bordered text, radial text, text area, complex paths, NURBS paths, cube, disk, grid, plane, geometric shapes, and volumetric area. It also comes with various camera types for viewing that can be dragged, zoomed, and rotated. Picking or selecting items in the scene can be accomplished in various ways depending on your needs (raycasting or color picking.) The framework currently has functionality for tooltips, animation, actor pools, color gradients, 2d physics, text, 1d/2d/3d textures, children, blending, clipping planes, view frustum culling, custom shaders, and custom actor states« less

    18. The phenomenology of action: a conceptual framework.

      PubMed

      Pacherie, Elisabeth

      2008-04-01

      After a long period of neglect, the phenomenology of action has recently regained its place in the agenda of philosophers and scientists alike. The recent explosion of interest in the topic highlights its complexity. The purpose of this paper is to propose a conceptual framework allowing for a more precise characterization of the many facets of the phenomenology of agency, of how they are related and of their possible sources. The key assumption guiding this attempt is that the processes through which the phenomenology of action is generated and the processes involved in the specification and control of action are strongly interconnected. I argue in favor of a three-tiered dynamic model of intention, link it to an expanded version of the internal model theory of action control and specification, and use this theoretical framework to guide an analysis of the contents, possible sources and temporal course of complementary aspects of the phenomenology of action. PMID:17950720

    19. A Kernel Classification Framework for Metric Learning.

      PubMed

      Wang, Faqiang; Zuo, Wangmeng; Zhang, Lei; Meng, Deyu; Zhang, David

      2015-09-01

      Learning a distance metric from the given training samples plays a crucial role in many machine learning tasks, and various models and optimization algorithms have been proposed in the past decade. In this paper, we generalize several state-of-the-art metric learning methods, such as large margin nearest neighbor (LMNN) and information theoretic metric learning (ITML), into a kernel classification framework. First, doublets and triplets are constructed from the training samples, and a family of degree-2 polynomial kernel functions is proposed for pairs of doublets or triplets. Then, a kernel classification framework is established to generalize many popular metric learning methods such as LMNN and ITML. The proposed framework can also suggest new metric learning methods, which can be efficiently implemented, interestingly, using the standard support vector machine (SVM) solvers. Two novel metric learning methods, namely, doublet-SVM and triplet-SVM, are then developed under the proposed framework. Experimental results show that doublet-SVM and triplet-SVM achieve competitive classification accuracies with state-of-the-art metric learning methods but with significantly less training time. PMID:25347887

    20. Overarching framework for data-based modelling

      NASA Astrophysics Data System (ADS)

      Schelter, Björn; Mader, Malenka; Mader, Wolfgang; Sommerlade, Linda; Platt, Bettina; Lai, Ying-Cheng; Grebogi, Celso; Thiel, Marco

      2014-02-01

      One of the main modelling paradigms for complex physical systems are networks. When estimating the network structure from measured signals, typically several assumptions such as stationarity are made in the estimation process. Violating these assumptions renders standard analysis techniques fruitless. We here propose a framework to estimate the network structure from measurements of arbitrary non-linear, non-stationary, stochastic processes. To this end, we propose a rigorous mathematical theory that underlies this framework. Based on this theory, we present a highly efficient algorithm and the corresponding statistics that are immediately sensibly applicable to measured signals. We demonstrate its performance in a simulation study. In experiments of transitions between vigilance stages in rodents, we infer small network structures with complex, time-dependent interactions; this suggests biomarkers for such transitions, the key to understand and diagnose numerous diseases such as dementia. We argue that the suggested framework combines features that other approaches followed so far lack.