Modeling the Role of Priming in Executive Control: Cognitive and Neural Constraints

DTIC Science & Technology

2012-01-24

theoretical and empirical advances in our understanding of cognitive control. We discovered new phenomena and developed theories to account for them. We...developed theories of cognitive control and visual attention that integrated mathematical psychology with cognitive science and with neuroscience. We...significant theoretical and empirical advances in our understanding of cognitive control. We discovered new phenomena and developed theories to account

The Social Structuring of Mental Health over the Adult Life Course: Advancing Theory in the Sociology of Aging

ERIC Educational Resources Information Center

Clarke, Philippa; Marshall, Victor; House, James; Lantz, Paula

2011-01-01

The sociology of aging draws on a broad array of theoretical perspectives and social theories from several disciplines, but rarely has it developed its own theories or theoretical perspectives. We build on past work to further advance and empirically test a model of mental health framed in terms of structural theorizing and situated within the…

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

Yang, Weitao

This Special Topic Issue on the Advances in Density Functional Theory, published as a celebration of the fifty years of density functional theory, contains a retrospective article, a perspective article, and a collection of original research articles that showcase recent theoretical advances in the field. It provides a timely discussion reflecting a cross section of our understanding, and the theoretical and computational developments, which have significant implications in broad areas of sciences and engineering.

Establishing a Research Agenda for Understanding the Role and Impact of Mental Health Peer Specialists.

PubMed

Chinman, Matthew; McInnes, D Keith; Eisen, Susan; Ellison, Marsha; Farkas, Marianne; Armstrong, Moe; Resnick, Sandra G

2017-09-01

Mental health peer specialists are individuals with serious mental illnesses who receive training to use their lived experiences to help others with serious mental illnesses in clinical settings. This Open Forum discusses the state of the research for mental health peer specialists and suggests a research agenda to advance the field. Studies have suggested that peer specialists vary widely in their roles, settings, and theoretical orientations. Theories of action have been proposed, but none have been tested. Outcome studies have shown benefits of peer specialists; however, many studies have methodological shortcomings. Qualitative descriptions of peer specialists are plentiful but lack grounding in implementation science frameworks. A research agenda advancing the field could include empirically testing theoretical mechanisms of peer specialists, developing a measure of peer specialist fidelity, conducting more rigorous outcomes studies, involving peer specialists in executing the research, and assessing various factors that influence implementing peer specialist services and testing strategies that could address those factors.

Advanced Numerical and Theoretical Methods for Photonic Crystals and Metamaterials

NASA Astrophysics Data System (ADS)

Felbacq, Didier

2016-11-01

This book provides a set of theoretical and numerical tools useful for the study of wave propagation in metamaterials and photonic crystals. While concentrating on electromagnetic waves, most of the material can be used for acoustic (or quantum) waves. For each presented numerical method, numerical code written in MATLAB® is presented. The codes are limited to 2D problems and can be easily translated in Python or Scilab, and used directly with Octave as well.

Community Size, Perceptions of Majority Opinion and Opinion Expression.

ERIC Educational Resources Information Center

Salmon, Charles T.; Oshagan, Hayg

A study examined structural determinants of opinion expression by merging two theoretical perspectives: the "spiral of silence" model advanced by Elisabeth Noelle-Neumann, and the structural approach to communication research offered by Phillip Tichenor, George Donohue, and Clarice Olien. The study also distinguished between different…

Plasma confinement theory and transport simulation

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

Ross, D.W.

The objectives are: (1) to advance the transport studies of tokamaks, including development and maintenance of the Magnetic Fusion Energy Database, and (2) to provide theoretical interpretation, modeling and equilibrium and stability studies for TEXT-Upgrade. Recent reports, publications, and conference presentations of the Fusion Research Center are listed.

Theoretical studies of the physics of the solar atmosphere

NASA Technical Reports Server (NTRS)

Hollweg, Joseph V.

1992-01-01

Significant advances in our theoretical basis for understanding several physical processes related to dynamical phenomena on the sun were achieved. We have advanced a new model for spicules and fibrils. We have provided a simple physical view of resonance absorption of MHD surface waves; this allowed an approximate mathematical procedure for obtaining a wealth of new analytical results which we applied to coronal heating and p-mode absorption at magnetic regions. We provided the first comprehensive models for the heating and acceleration of the transition region, corona, and solar wind. We provided a new view of viscosity under coronal conditions. We provided new insights into Alfven wave propagation in the solar atmosphere. And recently we have begun work in a new direction: parametric instabilities of Alfven waves.

Analysis of quasi-hybrid solid rocket booster concepts for advanced earth-to-orbit vehicles

NASA Technical Reports Server (NTRS)

Zurawski, Robert L.; Rapp, Douglas C.

1987-01-01

A study was conducted to assess the feasibility of quasi-hybrid solid rocket boosters for advanced Earth-to-orbit vehicles. Thermochemical calculations were conducted to determine the effect of liquid hydrogen addition, solids composition change plus liquid hydrogen addition, and the addition of an aluminum/liquid hydrogen slurry on the theoretical performance of a PBAN solid propellant rocket. The space shuttle solid rocket booster was used as a reference point. All three quasi-hybrid systems theoretically offer higher specific impulse when compared with the space shuttle solid rocket boosters. However, based on operational and safety considerations, the quasi-hybrid rocket is not a practical choice for near-term Earth-to-orbit booster applications. Safety and technology issues pertinent to quasi-hybrid rocket systems are discussed.

Theoretical Grounding: The "Missing Link" in Suicide Research.

ERIC Educational Resources Information Center

Rogers, James R.

2001-01-01

Discusses the strengths and limitations of the current pragmatic focus of research in suicidology and presents an argument for theoretical grounding as a precursor for continued advancement in this area. Presents an existential-constructivist framework of "meaning creation" as a theoretical heuristic for understanding suicide. Outlines general…

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. © Mary Ann Liebert, Inc.

Theoretical Problems in Materials Science

NASA Technical Reports Server (NTRS)

Langer, J. S.; Glicksman, M. E.

1985-01-01

Interactions between theoretical physics and material sciences to identify problems of common interest in which some of the powerful theoretical approaches developed for other branches of physics may be applied to problems in materials science are presented. A unique structure was identified in rapidly quenched Al-14% Mn. The material has long-range directed bonds with icosahedral symmetry which does not form a regular structure but instead forms an amorphous-like quasiperiodic structure. Finite volume fractions of second phase material is advanced and is coupled with nucleation theory to describe the formation and structure of precipitating phases in alloys. Application of the theory of pattern formation to the problem of dendrite formation is studied.

Propulsion Research at the Propulsion Research Center of the NASA Marshall Space Flight Center

NASA Technical Reports Server (NTRS)

Blevins, John; Rodgers, Stephen

2003-01-01

The Propulsion Research Center of the NASA Marshall Space Flight Center is engaged in research activities aimed at providing the bases for fundamental advancement of a range of space propulsion technologies. There are four broad research themes. Advanced chemical propulsion studies focus on the detailed chemistry and transport processes for high-pressure combustion, and on the understanding and control of combustion stability. New high-energy propellant research ranges from theoretical prediction of new propellant properties through experimental characterization propellant performance, material interactions, aging properties, and ignition behavior. Another research area involves advanced nuclear electric propulsion with new robust and lightweight materials and with designs for advanced fuels. Nuclear electric propulsion systems are characterized using simulated nuclear systems, where the non-nuclear power source has the form and power input of a nuclear reactor. This permits detailed testing of nuclear propulsion systems in a non-nuclear environment. In-space propulsion research is focused primarily on high power plasma thruster work. New methods for achieving higher thrust in these devices are being studied theoretically and experimentally. Solar thermal propulsion research is also underway for in-space applications. The fourth of these research areas is advanced energetics. Specific research here includes the containment of ion clouds for extended periods. This is aimed at proving the concept of antimatter trapping and storage for use ultimately in propulsion applications. Another activity in this involves research into lightweight magnetic technology for space propulsion applications.

Nonresidential Crime Attractors and Generators Elevate Perceived Neighborhood Crime and Incivilities

ERIC Educational Resources Information Center

McCord, Eric S.; Ratcliffe, Jerry H.; Garcia, R. Marie; Taylor, Ralph B.

2007-01-01

Recent studies have produced conflicting findings about the impacts of local nonresidential land uses on perceived incivilities. This study advances work in this area by developing a land-use perspective theoretically grounded in Brantingham and Brantingham's geometry of crime model in environmental criminology. That focus directs attention to…

The water dimer II: Theoretical investigations

NASA Astrophysics Data System (ADS)

Mukhopadhyay, Anamika; Xantheas, Sotiris S.; Saykally, Richard J.

2018-05-01

As the archetype of aqueous hydrogen bonding, the water dimer has been extensively studied by both theory and experiment for nearly seven decades. In this article, we present a detailed chronological review of the theoretical advances made using electronic structure methods to address the structure, hydrogen bonding and vibrational spectroscopy of the water dimer, as well as the role of its potential energy surface in the development of classical force fields to describe intermolecular interactions in clusters and the condensed phases of water.

The Water Dimer II: Theoretical Investigations

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

Mukhopadhyay, Anamika; Xantheas, Sotiris S.; Saykally, Richard J.

As the archetype of aqueous hydrogen bonding, the water dimer has been extensively studied by both theory and experiment for nearly seven decades. Here in this article, we present a detailed chronological review of the theoretical advances made using electronic structure methods to address the structure, hydrogen bonding and vibrational spectroscopy of the water dimer, as well as the role of its potential energy surface in the development of classical force fields to describe intermolecular interaction in clusters and the condensed phases of water.

The Water Dimer II: Theoretical Investigations

DOE PAGES

Mukhopadhyay, Anamika; Xantheas, Sotiris S.; Saykally, Richard J.

2018-03-29

As the archetype of aqueous hydrogen bonding, the water dimer has been extensively studied by both theory and experiment for nearly seven decades. Here in this article, we present a detailed chronological review of the theoretical advances made using electronic structure methods to address the structure, hydrogen bonding and vibrational spectroscopy of the water dimer, as well as the role of its potential energy surface in the development of classical force fields to describe intermolecular interaction in clusters and the condensed phases of water.

Political Geography and the Environment.

ERIC Educational Resources Information Center

Steinberg, Phillip E.

1997-01-01

Reviews recent theoretical advances in political geography, particularly those that stress the political conflict behind the production of space. Discusses how this has impacted the study of environmental phenomena such as hazards, human-land relationships, development, and international environmental governance. Suggests ways that political…

Contribution of developing advanced engineering methods in interdisciplinary studying the piston rings from 1.6 spark ignited Ford engine at Technical University of Cluj-Napoca

NASA Astrophysics Data System (ADS)

-Aurel Cherecheş, Ioan; -Ioana Borzan, Adela; -Laurean Băldean, Doru

2017-10-01

Study of construction and wearing process in the case of piston-rings and other significant components from internal combustion engines leads at any time to creative and useful optimizing ideas, both in designing and manufacturing phases. Main objective of the present paper is to realize an interdisciplinary research using advanced methods in piston-rings evaluation of a common vehicle on the streets which is Ford Focus FYDD. Specific objectives are a theoretical study of the idea for advanced analysis method in piston-rings evaluation and an applied research developed in at Technical University from Cluj-Napoca with the motor vehicle caught in the repairing process.

Advanced educational program in optoelectronics for undergraduates and graduates in electronics

NASA Astrophysics Data System (ADS)

Vladescu, Marian; Schiopu, Paul

2015-02-01

The optoelectronics education included in electronics curricula at Faculty of Electronics, Telecommunications and Information Technology of "Politehnica" University of Bucharest started in early '90s, and evolved constantly since then, trying to address the growing demand of engineers with a complex optoelectronics profile and to meet the increased requirements of microelectronics, optoelectronics, and lately nanotechnologies. Our goal is to provide a high level of theoretical background combined with advanced experimental tools in laboratories, and also with simulation platforms. That's why we propose an advanced educational program in optoelectronics for both grades of our study program, bachelor and master.

Deformation and Damage Studies for Advanced Structural Materials

NASA Technical Reports Server (NTRS)

2005-01-01

Advancements made in understanding deformation and damage of advanced structural materials have enabled the development of new technologies including the attainment of a nationally significant NASA Level 1 Milestone and the provision of expertise to the Shuttle Return to Flight effort. During this collaborative agreement multiple theoretical and experimental research programs, facilitating safe durable high temperature structures using advanced materials, have been conceived, planned, executed. Over 26 publications, independent assessments of structures and materials in hostile environments, were published within this agreement. This attainment has been recognized by 2002 Space Flight Awareness Team Award, 2004 NASA Group Achievement Award and 2003 and 2004 OAI Service Awards. Accomplishments in the individual research efforts are described as follows.

High-level theoretical study of the reaction between hydroxyl and ammonia: Accurate rate constants from 200 to 2500 K

NASA Astrophysics Data System (ADS)

Nguyen, Thanh Lam; Stanton, John F.

2017-10-01

Hydrogen abstraction from NH3 by OH to produce H2O and NH2—an important reaction in combustion of NH3 fuel—was studied with a theoretical approach that combines high level quantum chemistry and advanced chemical kinetics methods. Thermal rate constants calculated from first principles agree well (within 5%-20%) with available experimental data over a temperature range that extends from 200 to 2500 K. Quantum mechanical tunneling effects were found to be important; they lead to a decided curvature and non-Arrhenius behavior for the rate constant.

High-level theoretical study of the reaction between hydroxyl and ammonia: Accurate rate constants from 200 to 2500 K.

PubMed

Nguyen, Thanh Lam; Stanton, John F

2017-10-21

Hydrogen abstraction from NH 3 by OH to produce H 2 O and NH 2 -an important reaction in combustion of NH 3 fuel-was studied with a theoretical approach that combines high level quantum chemistry and advanced chemical kinetics methods. Thermal rate constants calculated from first principles agree well (within 5%-20%) with available experimental data over a temperature range that extends from 200 to 2500 K. Quantum mechanical tunneling effects were found to be important; they lead to a decided curvature and non-Arrhenius behavior for the rate constant.

Introducing Quantum Mechanics into General Chemistry

NASA Astrophysics Data System (ADS)

Popkowski, Iwona; Bascal, Hafed

2008-10-01

Periodicity has long been recognized as the tool that chemists can use to bring some order to investigating the chemistry of more than one hundred elements. Such studies provide useful tools for understanding a wide array of chemical principles. The advances in computational chemistry make it possible to study and teach such trends with hands on approach. In this study we utilize recently acquired software Spartan Pro to illustrate theoretical measurements of bond length, bond angle and dipole as compared to experimental data. We constructed a matrix of values obtained from the theoretical calculations and obtained trends in bond length, bond angle and dipoles for the several periodic groups.

Neutron generation from Z-pinches

NASA Astrophysics Data System (ADS)

Vikhrev, V. V.; Korolev, V. D.

2007-05-01

Recent advances in both experimental and theoretical studies on neutron generation in various Z-pinch facilities are reviewed. The main methods for enhancing neutron emission from the Z-pinch plasma are described, and the problems of igniting a thermonuclear burn wave in this plasma are discussed.

Studies in Leading and Organizing Schools. A Volume in Research and Theory in Educational Administration.

ERIC Educational Resources Information Center

Hoy, Wayne, Ed.; Miskel, Cecil, Ed.

This collection of research reports is intended to advance the understanding of schools through empirical study and theoretical analysis. The reports are as follows: "The Punctuated Equilibrium of National Reading Policy: Literacy's Changing Images and Venues" (Celia Sims and Cecil Miskel); "Productive Campus Leadership Responses to…

Contradictory Explorative Assessment. Multimodal Teacher/Student Interaction in Scandinavian Digital Learning Environments

ERIC Educational Resources Information Center

Kjällander, Susanne

2018-01-01

Assessment in the much-discussed digital divide in Scandinavian technologically advanced schools, is the study object of this article. Interaction is studied to understand assessment; and to see how assessment can be didactically designed to recognise students' learning. With a multimodal, design theoretical perspective on learning teachers' and…

Theoretical calculations of positron annihilation characteristics in inorganic solids -- Recent advances and problems

NASA Astrophysics Data System (ADS)

Sob, M.; Sormann, H.; Kuriplach, J.

Principles and applications of positron annihilation spectroscopy to electronic structure and defect studies are briefly reviewed and some recent advances and pending problems are illustrated by specific examples. In particular, it turns out that the sensitivity of calculated momentum densities of electron-positron annihilation pairs (MDAP) to the choice of electron crystal potential is higher or comparable to its sensitivity with respect to the choice of description of the electron-positron interaction. As a result, it is very hard to distinguish between various electron-positron interaction theories on the basis of the comparison of theoretical and experimental MDAPs. Furthermore, the positron affinity is determined theorttically for several systems having a band gap (semiconductors, insulators). It appears that the calculated positron affinities are significantly underestimated when compared to experimental data and, apparently, electron-positron interactions in such systems are not described satisfactorily by contemporary theoretical approaches. The above examples are related rather to electronic structure studies, but positrons are often used to investigate various open-volume defects in solids, which is dealt with in the last illustration. A non-selfconsistent computational technique suitable for the theoretical examination of configurations having large number (thousands) of non-equivalent atoms has been updated recently to treat non-periodic solids. It is based on the superposition of atomic densities in order to approximate the electronic density of the system studied. Though the charge redistribution due to selfconsistency effects is neglected, positron annihilation characteristics are determined quite reasonably. This allows for studying properties of extended defects like grain boundaries (and other interfaces), dislocations, precipitates, etc., which is very helpful when interpreting experimental positron annihilation data. Our technique is demonstrated for the case of nanocrystalline Ni where realistic atomic configurations are taken from large-scale molecular dynamics simulations.

Doing what's right: A grounded theory of ethical decision-making in occupational therapy.

PubMed

VanderKaay, Sandra; Letts, Lori; Jung, Bonny; Moll, Sandra E

2018-04-20

Ethical decision-making is an important aspect of reasoning in occupational therapy practice. However, the process of ethical decision-making within the broader context of reasoning is yet to be clearly explicated. The purpose of this study was to advance a theoretical understanding of the process by which occupational therapists make ethical decisions in day-to-day practice. A constructivist grounded theory approach was adopted, incorporating in-depth semi-structured interviews with 18 occupational therapists from a range of practice settings and years of experience. Initially, participants nominated as key informants who were able to reflect on their decision-making processes were recruited. Theoretical sampling informed subsequent stages of data collection. Participants were asked to describe their process of ethical decision-making using scenarios from clinical practice. Interview transcripts were analyzed using a systematic process of initial then focused coding, and theoretical categorization to construct a theory regarding the process of ethical decision-making. An ethical decision-making prism was developed to capture three main processes: Considering the Fundamental Checklist, Consulting Others, and Doing What's Right. Ethical decision-making appeared to be an inductive and dialectical process with the occupational therapist at its core. Study findings advance our understanding of ethical decision-making in day-to-day clinical practice.

Through the eye of the needle: recent advances in understanding biopolymer translocation.

PubMed

Panja, Debabrata; Barkema, Gerard T; Kolomeisky, Anatoly B

2013-10-16

In recent years polymer translocation, i.e., transport of polymeric molecules through nanometer-sized pores and channels embedded in membranes, has witnessed strong advances. It is now possible to observe single-molecule polymer dynamics during the motion through channels with unprecedented spatial and temporal resolution. These striking experimental studies have stimulated many theoretical developments. In this short theory-experiment review, we discuss recent progress in this field with a strong focus on non-equilibrium aspects of polymer dynamics during the translocation process.

Devil in the Details: A Critical Review of "Theoretical Loss".

PubMed

Tom, Matthew A; Shaffer, Howard J

2016-09-01

In their review of Internet gambling studies, Auer and Griffiths (J Gambl Stud 30(4), 879-887, 2014) question the validity of using bet size as an indicator of gambling intensity. Instead, in that review and in a response (Auer and Griffiths, J Gambl Stud 31(3), 921-931, 2015) to a previous comment (Braverman et al., J Gambl Stud 31(2), 359-366, 2015), Auer and Griffiths suggested using "theoretical loss" as a preferable measure of gambling intensity. This comment extends and advances the discussion about measures of gambling intensity. In this paper, we describe previously identified problems that Auer and Griffiths need to address to sustain theoretical loss as a viable measure of gambling intensity and add details to the discussion that demonstrate difficulties associated with the use of theoretical loss with certain gambling games.

A Brief History of the Institute of Theoretical Physics in the Chinese Academy of Sciences since 1978

NASA Astrophysics Data System (ADS)

Jinyan, Liu

2014-03-01

The Institute of Theoretical Physics (ITP), Chinese academy of Sciences (CAS), founded in June 1978, is a specialized institute studying major issues in the fundamental research of theoretical physics. ITP has played an important role in the development of theoretical physics in China, especially in organizing and undertaking major national projects, expanding international exchanges and cooperation, and nurturing advanced researchers. My presentation will examine the reasons why ITP was founded in 1978 and why Peng Huanwu and Zhou Guangzhao, two prominent Chinese theorists, were chosen as the first and second directors of ITP. Moreover, I will summarize ITP's scientific activities and achievements in the past 35 years. Last but not least, I will compare ITP with university physics departments and explore its unique characters (both strength and weakness).

Advancing nursing practice: redefining the theoretical and practical integration of knowledge.

PubMed

Christensen, Martin

2011-03-01

The aim of this paper is to offer an alternative knowing-how knowing-that framework of nursing knowledge, which in the past has been accepted as the provenance of advanced practice. The concept of advancing practice is central to the development of nursing practice and has been seen to take on many different forms depending on its use in context. To many it has become synonymous with the work of the advanced or expert practitioner; others have viewed it as a process of continuing professional development and skills acquisition. Moreover, it is becoming closely linked with practice development. However, there is much discussion as to what constitutes the knowledge necessary for advancing and advanced practice, and it has been suggested that theoretical and practical knowledge form the cornerstone of advanced knowledge. The design of this article takes a discursive approach as to the meaning and integration of knowledge within the context of advancing nursing practice. A thematic analysis of the current discourse relating to knowledge integration models in an advancing and advanced practice arena was used to identify concurrent themes relating to the knowing-how knowing-that framework which commonly used to classify the knowledge necessary for advanced nursing practice. There is a dichotomy as to what constitutes knowledge for advanced and advancing practice. Several authors have offered a variety of differing models, yet it is the application and integration of theoretical and practical knowledge that defines and develops the advancement of nursing practice. An alternative framework offered here may allow differences in the way that nursing knowledge important for advancing practice is perceived, developed and coordinated. What has inevitably been neglected is that there are various other variables which when transposed into the existing knowing-how knowing-that framework allows for advanced knowledge to be better defined. One of the more notable variables is pattern recognition, which became the focus of Benner's work on expert practice. Therefore, if this is included into the knowing-how knowing-that framework, the knowing-how becomes the knowledge that contributes to advancing and advanced practice and the knowing-that becomes the governing action based on a deeper understanding of the problem or issue. © 2011 Blackwell Publishing Ltd.

Adding structure to the transition process to advanced mathematical activity

NASA Astrophysics Data System (ADS)

Engelbrecht, Johann

2010-03-01

The transition process to advanced mathematical thinking is experienced as traumatic by many students. Experiences that students had of school mathematics differ greatly to what is expected from them at university. Success in school mathematics meant application of different methods to get an answer. Students are not familiar with logical deductive reasoning, required in advanced mathematics. It is necessary to assist students in this transition process, in moving from general to mathematical thinking. In this article some structure is suggested for this transition period. This essay is an argumentative exposition supported by personal experience and international literature. This makes this study theoretical rather than empirical.

Recent Theoretical Studies On Excitation and Recombination

NASA Technical Reports Server (NTRS)

Pradhan, Anil K.

2000-01-01

New advances in the theoretical treatment of atomic processes in plasmas are described. These enable not only an integrated, unified, and self-consistent treatment of important radiative and collisional processes, but also large-scale computation of atomic data with high accuracy. An extension of the R-matrix work, from excitation and photoionization to electron-ion recombination, includes a unified method that subsumes both the radiative and the di-electronic recombination processes in an ab initio manner. The extensive collisional calculations for iron and iron-peak elements under the Iron Project are also discussed.

The Impact of Semantic Impairment on Verbal Short-Term Memory in Stroke Aphasia and Semantic Dementia: A Comparative Study

ERIC Educational Resources Information Center

Jefferies, Elizabeth; Hoffman, Paul; Jones, Roy; Lambon Ralph, Matthew A.

2008-01-01

This study presents the first direct comparison of immediate serial recall in semantic dementia (SD) and transcortical sensory aphasia (TSA). Previous studies of the effect of semantic impairment on verbal short-term memory (STM) have led to important theoretical advances. However, different conclusions have been drawn from these two groups. This…

Theoretical status of the lifetime predictions:. (ΔΓ/Γ)Bs, τB+/τBd and τΛb/τBd

NASA Astrophysics Data System (ADS)

Lenz, Alexander

2002-04-01

We give a review of the theoretical status of the lifetime predictions in the standard model. In case of (ΔΓ/Γ)Bs we are already in a rather advanced stage. We obtain (Δ Γ /Γ )Bs = (9.3+3.4-4.6)%. It seems to be difficult to improve these errors substantially. In addition now some experimental results are available. For τB+/τBd and τΛb/τBd the theoretical status is much less advanced and the discrepancy between experiment and theory still remains. We conclude with a what-to-do-list for theorists.

Color and psychological functioning: a review of theoretical and empirical work

PubMed Central

Elliot, Andrew J.

2015-01-01

In the past decade there has been increased interest in research on color and psychological functioning. Important advances have been made in theoretical work and empirical work, but there are also important weaknesses in both areas that must be addressed for the literature to continue to develop apace. In this article, I provide brief theoretical and empirical reviews of research in this area, in each instance beginning with a historical background and recent advancements, and proceeding to an evaluation focused on weaknesses that provide guidelines for future research. I conclude by reiterating that the literature on color and psychological functioning is at a nascent stage of development, and by recommending patience and prudence regarding conclusions about theory, findings, and real-world application. PMID:25883578

An Astrosociological Perspective on Space-Capable vs. Spacefaring Societies

NASA Astrophysics Data System (ADS)

Pass, J.

As with any academic field, astrosociology allows for an endless number of competing theoretical models and hypotheses. One possible theoretical model is presented here that starts with the premise that even the most advanced societies today are extremely far from achieving a spacefaring status. The most advanced nation states are, in fact, space-capable societies because they have the capacity to send cargo and humans into low Earth orbit and beyond. However, their social structures and cultures lack fundamental characteristics that would allow for their designation as spacefaring societies. This article describes the characteristics of a theoretical spacefaring society and argues that getting there from our current status as space-capable societies is a long and arduous process, and it is not a definite outcome whatsoever. While a continuum is offered, it represents an imprecise path that can retrograde or fall apart at any time. Thus, this theoretical model provides one possible series of an unfolding of events that result in the creation of characteristics of the social fabric that may result in movement along the continuum toward a spacefaring society. Movement along the continuum results in an accumulation of coordinated spacefaring characteristics for a given society. Simultaneously, strictly terrestrial characteristics disappear or transform themselves into hybrid forms that include spacefaring features. This exercise demonstrates that this theoretical exercise has a number of benefits for astrosociologists conducting research in the area of spacefaring theory. Moreover, it makes the case for the idea that the study of the theoretical transformation from a space-capable to a spacefaring society includes implications for current and future 1) space policy in the public sector and 2) corporate decision-making related to space in the private sector.

Organizing the Baby Boomer Construct: An Exploration of Marketing, Social Systems, and Culture

ERIC Educational Resources Information Center

Lipschultz, Jeremy H.; Hilt, Michael L.; Reilly, Hugh J.

2007-01-01

Baby boomer trends are applied in the development of a conceptual framework that offers a social systems and cultural model for future studies. While there has been considerable recent attention paid to baby boomers, the studies lack a coherent theoretical base that would allow for more advanced and continuing research. Aging baby boomers heading…

Spatial synchrony propagates through a forest food web via consumer-resource interactions

Treesearch

Kyle J. ​Haynes; Andrew M. Liebhold; Todd M. Fearer; Guiming Wang; Gary W. Norman; Derek M. Johnson

2009-01-01

In many study systems, populations fluctuate synchronously across large regions. Several mechanisms have been advanced to explain this, but their importance in nature is often uncertain. Theoretical studies suggest that spatial synchrony initiated in one species through Moran effects may propagate among trophically linked species, but evidence for this in nature is...

Plasma confinement theory and transport simulation. Technical progress report, May 1, 1991--April 30, 1992

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

Ross, D.W.

The objectives are: (1) to advance the transport studies of tokamaks, including development and maintenance of the Magnetic Fusion Energy Database, and (2) to provide theoretical interpretation, modeling and equilibrium and stability studies for TEXT-Upgrade. Recent reports, publications, and conference presentations of the Fusion Research Center are listed.

High-level theoretical study of the reaction between hydroxyl and ammonia: Accurate rate constants from 200 to 2500 K

DOE PAGES

Nguyen, Thanh Lam; Stanton, John F.

2017-06-02

Hydrogen abstraction from NH 3 by OH to produce H 2O and NH 2 — an important reaction in combustion of NH 3 fuel — was studied with a theoretical approach that combines high level quantum chemistry and advanced chemical kinetics methods. Thermal rate constants calculated from first principles agree well (within 5 to 20%) with available experimental data over a temperature range that extends from 200 to 2500 K. Here, quantum mechanical tunneling effects were found to be important; they lead to a decided curvature and non-Arrhenius behavior for the rate constant.

Propagation studies using a theoretical ionosphere model

NASA Technical Reports Server (NTRS)

Lee, M.

1973-01-01

The mid-latitude ionospheric and neutral atmospheric models are coupled with an advanced three dimensional ray tracing program to see what success would be obtained in predicting the wave propagation conditions and to study to what extent the use of theoretical ionospheric models is practical. The Penn State MK 1 ionospheric model, the Mitra-Rowe D region model, and the Groves' neutral atmospheric model are used throughout this work to represent the real electron densities and collision frequencies. The Faraday rotation and differential Doppler velocities from satellites, the propagation modes for long distance high frequency propagation, the group delays for each mode, the ionospheric absorption, and the spatial loss are all predicted.

Propagation studies using a theoretical ionosphere model

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

Lee, M.K.

1973-03-01

The mid-latitude ionospheric and neutral atmospheric models are coupled with an advanced three dimensional ray-tracing pron predicting the wave propagation conditions and to study to what extent the use of theoretical ionospheric models is practical. The Penn State MK 1 ionospheric model, the Mitra--Rowe D-region model, and the Groves' neutral atmospheric model are used throughout ihis work to represent the real electron densities and collision frequencies. The Faraday rotation and differential Doppler velocities from satellites, the propagation modes for long-distance high-frequency propagation, the group delays for each mode, the ionospheric absorption, and the spatial loss are all predicted. (auth) (STAR)

Study on the Integrated Geophysic Methods and Application of Advanced Geological Detection for Complicated Tunnel

NASA Astrophysics Data System (ADS)

Zhou, L.; Xiao, G.

2014-12-01

The engineering geological and hydrological conditions of current tunnels are more and more complicated, as the tunnels are elongated with deeper depth. In constructing these complicated tunnels, geological hazards prone to occur as induced by unfavorable geological bodies, such as fault zones, karst or hydrous structures, etc. The working emphasis and difficulty of the advanced geological exploration for complicated tunnels are mainly focused on the structure and water content of these unfavorable geological bodies. The technical aspects of my paper systematically studied the advanced geological exploration theory and application aspects for complicated tunnels, with discussion on the key technical points and useful conclusions. For the all-aroundness and accuracy of advanced geological exploration results, the objective of my paper is targeted on the comprehensive examination on the structure and hydrous characteristic of the unfavorable geological bodies in complicated tunnels. By the multi-component seismic modeling on a more real model containing the air medium, the wave field response characteristics of unfavorable geological bodies can be analyzed, thus providing theoretical foundation for the observation system layout, signal processing and interpretation of seismic methods. Based on the tomographic imaging theory of seismic and electromagnetic method, 2D integrated seismic and electromagnetic tomographic imaging and visualization software was designed and applied in the advanced drilling hole in the tunnel face, after validation of the forward and inverse modeling results on theoretical models. The transmission wave imaging technology introduced in my paper can be served as a new criterion for detection of unfavorable geological bodies. After careful study on the basic theory, data processing and interpretation, practical applications of TSP and ground penetrating radar (GPR) method, as well as serious examination on their application examples, my paper formulated a suite of comprehensive application system of seismic and electromagnetic methods for the advanced geological exploration of complicated tunnels. This research is funded by National Natural Science Foundation of China (Grant No. 41202223) .

Advances in Learning and Behavioral Disabilities. Volume 10. Part A: Theoretical Perspectives [and] Part B: Intervention Research.

ERIC Educational Resources Information Center

Scruggs, Thomas E., Ed.; Mastropieri, Margo A., Ed.

This two-volume set presents 11 papers on the state of the art in learning and behavioral disabilities, the first volume, Part A, includes 6 papers providing theoretical perspectives and, the second volume, Part B, includes 5 papers on intervention research. The theoretical papers are: "Defining Emotional or Behavioral Disorders: Divergence…

Aerodynamic Analyses Requiring Advanced Computers, part 2

NASA Technical Reports Server (NTRS)

1975-01-01

Papers given at the conference present the results of theoretical research on aerodynamic flow problems requiring the use of advanced computers. Topics discussed include two-dimensional configurations, three-dimensional configurations, transonic aircraft, and the space shuttle.

Nanotwinned and hierarchical nanotwinned metals: a review of experimental, computational and theoretical efforts

NASA Astrophysics Data System (ADS)

Sun, Ligang; He, Xiaoqiao; Lu, Jian

2018-02-01

The recent studies on nanotwinned (NT) and hierarchical nanotwinned (HNT) face-centered cubic (FCC) metals are presented in this review. The HNT structures have been supposed as a kind of novel structure to bring about higher strength/ductility than NT counterparts in crystalline materials. We primarily focus on the recent developments of the experimental, atomistic and theoretical studies on the NT and HNT structures in the metallic materials. Some advanced bottom-up and top-down techniques for the fabrication of NT and HNT structures are introduced. The deformation induced HNT structures are available by virtue of severe plastic deformation (SPD) based techniques while the synthesis of growth HNT structures is so far almost unavailable. In addition, some representative molecular dynamics (MD) studies on the NT and HNT FCC metals unveil that the nanoscale effects such as twin spacing, grain size and plastic anisotropy greatly alter the performance of NT and HNT metals. The HNT structures may initiate unique phenomena in comparison with the NT ones. Furthermore, based on the phenomena and mechanisms revealed by experimental and MD simulation observations, a series of theoretical models have been proposed. They are effective to describe the mechanical behaviors of NT and HNT metals within the applicable scope. So far the development of manufacturing technologies of HNT structures, as well as the studies on the effects of HNT structures on the properties of metals are still in its infancy. Further exploration is required to promote the design of advanced materials.

Study of the Solar Cycle from Space

NASA Technical Reports Server (NTRS)

1980-01-01

The objectives of and benefits to be derived from a program of solar cycle research are discussed with emphasis on the role space observations will play in this venture. The strategy to be employed in the coming decade is considered as well as crucial missions, experiments, and the theoretical advances required.

Leadership and School Quality. Research and Theory in Educational Administration

ERIC Educational Resources Information Center

DiPaola, Michael, Ed.; Forsyth, Patrick B., Ed.

2015-01-01

"Leadership and School Quality" is the twelfth book in a series on research and theory dedicated to advancing understanding of schools through empirical study and theoretical analysis. The chapters include analyses that investigate relationships between school organizations and leadership behaviors that have an impact on teacher and…

What Matters in College to Students: Critical Incidents in the Undergraduate Experience

ERIC Educational Resources Information Center

Vianden, Jörg

2015-01-01

This article advances that undergraduates are partners to higher education institutions in establishing the educational enterprise. Leaning on student relationship management as a theoretical construct and the critical incident technique as method, the study found 58 undergraduates' interpersonal interactions with faculty, staff, and peers…

An Advance toward Instructional Management: Prescriptive Knowledge Base of Learner Control.

ERIC Educational Resources Information Center

Chung, Jaesam

This paper discusses learner control as one of the main issues in instructional management and the importance of effectiveness and efficiency in the context of instructional/learning systems, and develops instructional prescriptions for learner control in a smorgasbord fashion. Strategies from both empirical and theoretical studies related to…

Investigating Connections among Reading, Writing, and Language Development: A Multiliteracies Perspective

ERIC Educational Resources Information Center

Paesani, Kate

2016-01-01

This study explores relationships among reading literature, creative writing, and language development in a university-level advanced French grammar course through the theoretical lens of the multiliteracies framework. The goal is to investigate reading-writing connections and whether these literacy practices facilitate students' understanding and…

Reframing Approaches to Narrating Young People's Conceptualisations of Citizenship in Education Research

ERIC Educational Resources Information Center

Akar, Bassel

2018-01-01

Large-scale quantitative studies on citizenship and citizenship education research have advanced an international and comparative field of democratic citizenship education. Their instruments, however, informed by theoretical variables constructed in Western Europe and North America mostly measure young people's understandings of a predefined…

Aerodynamic Analyses Requiring Advanced Computers, Part 1

NASA Technical Reports Server (NTRS)

1975-01-01

Papers are presented which deal with results of theoretical research on aerodynamic flow problems requiring the use of advanced computers. Topics discussed include: viscous flows, boundary layer equations, turbulence modeling and Navier-Stokes equations, and internal flows.

The influence of capture-recapture methodology on the evolution of the North American Bird Banding Program

USGS Publications Warehouse

Tautin, J.; Lebreton, J.-D.; North, P.M.

1993-01-01

Capture-recapture methodology has advanced greatly in the last twenty years and is now a major factor driving the continuing evolution of the North American bird banding program. Bird banding studies are becoming more scientific with improved study designs and analytical procedures. Researchers and managers are gaining more reliable knowledge which in turn betters the conservation of migratory birds. The advances in capture-recapture methodology have benefited gamebird studies primarily, but nongame bird studies will benefit similarly as they expand greatly in the next decade. Further theoretical development of capture-recapture methodology should be encouraged, and, to maximize benefits of the methodology, work on practical applications should be increased.

Sarcasm and Advanced Theory of Mind Understanding in Children and Adults with Prelingual Deafness

ERIC Educational Resources Information Center

O'Reilly, Karin; Peterson, Candida C.; Wellman, Henry M.

2014-01-01

Two studies addressed key theoretical debates in theory of mind (ToM) development by comparing (a) deaf native signers (n = 18), (b) deaf late signers (n = 59), and (c) age-matched hearing persons (n = 74) in childhood (Study 1: n = 81) and adulthood (Study 2: n = 70) on tests of first- and second-order false belief and conversational sarcasm.…

Theoretical Modeling and Electromagnetic Response of Complex Metamaterials

DTIC Science & Technology

2017-03-06

AFRL-AFOSR-VA-TR-2017-0042 Theoretical Modeling and Electromagnetic Response of Complex Metamaterials Andrea Alu UNIVERSITY OF TEXAS AT AUSTIN Final...Nov 2016 4. TITLE AND SUBTITLE Theoretical Modeling and Electromagnetic Response of Complex Metamaterials 5a.  CONTRACT NUMBER 5b.  GRANT NUMBER...based on parity-time symmetric metasurfaces, and various advances in electromagnetic and acoustic theory and applications. Our findings have opened

Images of Inherited War: Three American Presidents in Vietnam

DTIC Science & Technology

2011-06-01

Dependent Realism to demonstrate how theoretical advances in modern physical science correlate to cognitive theories in International Relations. We...Quantum Physics and Model-Dependent Realism In his book, The Grand Design, theoretical physicist and cosmologist Stephen Hawking draws on theoretical...exhibited wave-like properties and that existing scientific laws could not account for their behavior. Newtonian physics was “built on a framework

Advanced Concepts Theory Annual Report 1983.

DTIC Science & Technology

1984-05-18

variety of theoretical models, tools, and computational strategies to understand, guide, and predict the behavior of high brightness, laboratory x-ray... theoretical models must treat hard and soft x-ray emission from different electron configurations with K, L, and M shells, and they must include... theoretical effort has basis for comprehending the trends which appear in the been devoted to elucidating the effects of opacity on the numerical results

Developing Second Language Writing through Scaffolding in the ZPD: A Magazine Project for an Authentic Audience

ERIC Educational Resources Information Center

Schwieter, John W.

2010-01-01

In the present study, Vygotsky's (1978, 1986) sociocultural framework of the zone of proximal development (ZPD) and scaffolding writing (Bodrova & Leong, 1995, 1996; Ross, 1976) are used as the theoretical basis to study the development of second language writing. A course project is presented in which advanced English language learners of Spanish…

The Effects of Cognitively Guided Instruction on Mathematics Achievement of Second Grade Children

ERIC Educational Resources Information Center

Hendricks, Cynthia

2013-01-01

In 2010, 6% of students in the United States were performing at an advanced level in mathematics. During the previous year, the United States produced over 987,000 low math achievers. The theoretical foundations of this research project study were found in Cognitively Guided Instruction (CGI). The research problem addressed in this study is the…

Computational study of the interplay between intermolecular interactions and CO2 orientations in type I hydrates.

PubMed

Pérez-Rodríguez, M; Vidal-Vidal, A; Míguez, J M; Blas, F J; Torré, J-P; Piñeiro, M M

2017-01-25

Carbon dioxide (CO 2 ) molecules show a rich orientation landscape when they are enclathrated in type I hydrates. Previous studies have described experimentally their preferential orientations, and some theoretical works have explained, but only partially, these experimental results. In the present paper, we use classical molecular dynamics and electronic density functional theory to advance in the theoretical description of CO 2 orientations within type I hydrates. Our results are fully compatible with those previously reported, both theoretical and experimental, the geometric shape of the cavities in hydrate being, and therefore, the steric constraints, responsible for some (but not all) preferential angles. In addition, our calculations also show that guest-guest interactions in neighbouring cages are a key factor to explain the remaining experimental angles. Besides the implication concerning equation of state hydrate modeling approximations, the conclusion is that these guest-guest interactions should not be neglected, contrary to the usual practice.

Theory and practice in sport psychology and motor behaviour needs to be constrained by integrative modelling of brain and behaviour.

PubMed

Keil, D; Holmes, P; Bennett, S; Davids, K; Smith, N

2000-06-01

Because of advances in technology, the non-invasive study of the human brain has enhanced the knowledge base within the neurosciences, resulting in an increased impact on the psychological study of human behaviour. We argue that application of this knowledge base should be considered in theoretical modelling within sport psychology and motor behaviour alongside existing ideas. We propose that interventions founded on current theoretical and empirical understanding in both psychology and the neurosciences may ultimately lead to greater benefits for athletes during practice and performance. As vehicles for exploring the arguments of a greater integration of psychology and neurosciences research, imagery and perception-action within the sport psychology and motor behaviour domains will serve as exemplars. Current neuroscience evidence will be discussed in relation to theoretical developments; the implications for sport scientists will be considered.

Theoretical Fluid Mechanics

NASA Astrophysics Data System (ADS)

Fitzpatrick, Richard

2017-12-01

'Theoretical Fluid Mechanics' has been written to aid physics students who wish to pursue a course of self-study in fluid mechanics. It is a comprehensive, completely self-contained text with equations of fluid mechanics derived from first principles, and any required advanced mathematics is either fully explained in the text, or in an appendix. It is accompanied by about 180 exercises with completely worked out solutions. It also includes extensive sections on the application of fluid mechanics to topics of importance in astrophysics and geophysics. These topics include the equilibrium of rotating, self-gravitating, fluid masses; tidal bores; terrestrial ocean tides; and the Eddington solar model.

Theoretical analysis of intracortical microelectrode recordings

NASA Astrophysics Data System (ADS)

Lempka, Scott F.; Johnson, Matthew D.; Moffitt, Michael A.; Otto, Kevin J.; Kipke, Daryl R.; McIntyre, Cameron C.

2011-08-01

Advanced fabrication techniques have now made it possible to produce microelectrode arrays for recording the electrical activity of a large number of neurons in the intact brain for both clinical and basic science applications. However, the long-term recording performance desired for these applications is hindered by a number of factors that lead to device failure or a poor signal-to-noise ratio (SNR). The goal of this study was to identify factors that can affect recording quality using theoretical analysis of intracortical microelectrode recordings of single-unit activity. Extracellular microelectrode recordings were simulated with a detailed multi-compartment cable model of a pyramidal neuron coupled to a finite-element volume conductor head model containing an implanted recording microelectrode. Recording noise sources were also incorporated into the overall modeling infrastructure. The analyses of this study would be very difficult to perform experimentally; however, our model-based approach enabled a systematic investigation of the effects of a large number of variables on recording quality. Our results demonstrate that recording amplitude and noise are relatively independent of microelectrode size, but instead are primarily affected by the selected recording bandwidth, impedance of the electrode-tissue interface and the density and firing rates of neurons surrounding the recording electrode. This study provides the theoretical groundwork that allows for the design of the microelectrode and recording electronics such that the SNR is maximized. Such advances could help enable the long-term functionality required for chronic neural recording applications.

Theoretical analysis of intracortical microelectrode recordings

PubMed Central

Lempka, Scott F; Johnson, Matthew D; Moffitt, Michael A; Otto, Kevin J; Kipke, Daryl R; McIntyre, Cameron C

2011-01-01

Advanced fabrication techniques have now made it possible to produce microelectrode arrays for recording the electrical activity of a large number of neurons in the intact brain for both clinical and basic science applications. However, the long-term recording performance desired for these applications is hindered by a number of factors that lead to device failure or a poor signal-to-noise ratio (SNR). The goal of this study was to identify factors that can affect recording quality using theoretical analysis of intracortical microelectrode recordings of single-unit activity. Extracellular microelectrode recordings were simulated with a detailed multi-compartment cable model of a pyramidal neuron coupled to a finite element volume conductor head model containing an implanted recording microelectrode. Recording noise sources were also incorporated into the overall modeling infrastructure. The analyses of this study would be very difficult to perform experimentally; however, our model-based approach enabled a systematic investigation of the effects of a large number of variables on recording quality. Our results demonstrate that recording amplitude and noise are relatively independent of microelectrode size, but instead are primarily affected by the selected recording bandwidth, impedance of the electrode-tissue interface, and the density and firing rates of neurons surrounding the recording electrode. This study provides the theoretical groundwork that allows for the design of the microelectrode and recording electronics such that the SNR is maximized. Such advances could help enable the long-term functionality required for chronic neural recording applications. PMID:21775783

Narratives of Assimilation, Divergence, and Hybridity: The Reproduction Decisions of College-Educated Mexican American Women

ERIC Educational Resources Information Center

Alvarado, Emmanuel; Nehring, Daniel

2012-01-01

Our study explored cultural understandings surrounding the reproductive decisions of US-born, college-educated Mexican American women through a series of semi-structured in-depth interviews. In considering the results, this article advances debates on Latina women's reproductive choices beyond the theoretical paradigms of "assimilation" and…

Contact, Attitude and Motivation in the Learning of Catalan at Advanced Levels

ERIC Educational Resources Information Center

Hamilton, Colleen; Serrano, Raquel

2015-01-01

The theoretical complexity of current understandings of second language (L2) identity has brought the study of language learning motivations from basic concepts of intrinsic, integrative and instrumental motives to a more dynamic construct that interacts with background factors, learning contexts and proficiency levels. This cross-sectional study…

Educational Change: A Case for a "Pedagogy of Compassion"

ERIC Educational Resources Information Center

Vandeyar, Saloshna; Swart, Ronel

2016-01-01

This paper sets out to advance the concept of an "epistemology of compassion" first proposed by Vandeyar (2013; 2016). Utilising a single embedded case study and the theoretical mooring of post-conflict pedagogy this paper attempts to find links between Jansen's perceptions of a post-conflict pedagogy and Freirean pedagogy and to argue a…

Advancing Fourth-Grade Students' Understanding of Arithmetic Properties with Instruction That Promotes Mathematical Argumentation

ERIC Educational Resources Information Center

Rumsey, Chepina Witkowski

2012-01-01

The goals for this study were to investigate how fourth-grade students developed an understanding of the arithmetic properties when instruction promoted mathematical argumentation and to identify the characteristics of students' arguments. Using the emergent perspective as an overarching theoretical perspective helped distinguish between two…

A Framework for Mathematical Thinking: The Case of Linear Algebra

ERIC Educational Resources Information Center

Stewart, Sepideh; Thomas, Michael O. J.

2009-01-01

Linear algebra is one of the unavoidable advanced courses that many mathematics students encounter at university level. The research reported here was part of the first author's recent PhD study, where she created and applied a theoretical framework combining the strengths of two major mathematics education theories in order to investigate the…

Reading Comprehension Is Embodied: Theoretical and Practical Considerations

ERIC Educational Resources Information Center

Sadoski, Mark

2018-01-01

In this review, I advance the embodied cognition movement in cognitive psychology as both a challenge and an invitation for the study of reading comprehension. Embodied cognition challenges theories which assume that mental operations are based in a common, abstract, amodal code of propositions and schemata. Based on growing research in behavioral…

Human Dignity and Humiliation Studies: A Global Network Advancing Dignity through Dialogue

ERIC Educational Resources Information Center

Lindner, Evelin G.; Hartling, Linda M.; Spalthoff, Ulrich

2011-01-01

Human rights are universally based on the concept of human dignity. Various international organizations are developing the theoretical, legal, and political framework for human rights. The underlying concept of human dignity is less disputed, but also receives less attention. This shortcoming is addressed by a worldwide group of scholars and…

[PHYSIOLOGY AND PHARMACOLOGICAL PROPERTIES OF NANOMATERIALS].

PubMed

Chekman, I S

2015-01-01

Literature data and results of our department studies on theoretical and practical basics of nanoscience were summarized in the article. Much attention is paid to research in the field of physical, chemical, biological, medical, physiological, pharmacological, and toxicological properties of nanomaterials with the aim of their wider implementation into practice lately. The discovery of new quantum/wave properties of nanoparticles is of particular importance. The author of the article advances an idea: wave properties of nanomaterials play greater role with a decrease in particle size. The preponderance of wave properties compared with corpuscular ones in nanostructures determines a great change in their physical. chemical properties and an increase in physical, mechanical biological, physiological, pharmacological, and toxicologica activity. The idea advanced in the article hasn't been verified by theoretical or experimental studies for now. Joined efforts of scientists of different scientific fields are needed. A confirmation of hypothesis by specific findings will be of great importance for physiology, medicine, pharmacology and promote an implementation of new efficacious preparations into clinical practice. New fundamental discoveries could be made only by multidisciplinary approach.

From ab Initio Potential Energy Surfaces to State-Resolved Reactivities: X + H 2O ↔ HX + OH [X = F, Cl, and O( 3P)] Reactions

DOE PAGES

Li, Jun; Jiang, Bin; Song, Hongwei; ...

2015-04-17

Here, we survey the recent advances in theoretical understanding of quantum state resolved dynamics, using the title reactions as examples. It is shown that the progress was made possible by major developments in two areas. First, an accurate analytical representation of many high-level ab initio points over a large configuration space can now be made with high fidelity and the necessary permutation symmetry. The resulting full-dimensional global potential energy surfaces enable dynamical calculations using either quasi-classical trajectory or more importantly quantum mechanical methods. The second advance is the development of accurate and efficient quantum dynamical methods, which are necessary formore » providing a reliable treatment of quantum effects in reaction dynamics such as tunneling, resonances, and zero-point energy. The powerful combination of the two advances has allowed us to achieve a quantitatively accurate characterization of the reaction dynamics, which unveiled rich dynamical features such as steric steering, strong mode specificity, and bond selectivity. The dependence of reactivity on reactant modes can be rationalized by the recently proposed sudden vector projection model, which attributes the mode specificity and bond selectivity to the coupling of reactant modes with the reaction coordinate at the relevant transition state. The deeper insights provided by these theoretical studies have advanced our understanding of reaction dynamics to a new level.« less

Theorizing the Entrepreneurial University: Open Questions and Possible Answers

ERIC Educational Resources Information Center

Sotiris, Panagiotis

2012-01-01

This article attempts to address theoretical questions regarding the transition towards an entrepreneurial university and the changes associated with this process, namely the increased commodification, the competitive quest for private funding and the introduction of business management practices. The important theoretical advances made in the…

Developing Idiomatic Competence in the ESOL Classroom: A Pragmatic Account

ERIC Educational Resources Information Center

Liontas, John I.

2015-01-01

Building on previous theoretical constructs and empirical findings on idioms, this article advances an integrated theoretical and methodological framework for developing idiomatic competence in English for speakers of other languages (ESOL). Beginning with a definition of the term "idiomatic competence," the author then presents a…

Theoretical Chemistry Comes Alive: Full Partner with Experiment.

ERIC Educational Resources Information Center

Goddard, William A., III

1985-01-01

The expected thrust for theoretical chemistry in the next decade will be to combine knowledge of fundamental chemical steps/interactions with advances in chemical dynamics, irreversible statistical mechanics, and computer technology to produce simulations of chemical systems with reaction site competition. A sample simulation (using the enzyme…

VIM: A Platform for Violent Intent Modeling

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

Sanfilippo, Antonio P.; Schryver, Jack C.; Whitney, Paul D.

2009-03-31

Radical and contentious political/religious activism may or may not evolve into violent behavior depending on contextual factors related to social, political, cultural and infrastructural conditions. Significant theoretical advances have been made in understanding these contextual factors and the import of their interrelations. However, there has been relative little progress in the development of processes and capabilities which leverage such theoretical advances to automate the anticipatory analysis of violent intent. In this paper, we describe a framework which implements such processes and capabilities, and discuss the implications of using the resulting system to assess the emergence of radicalization leading to violence.

Molecular anions.

PubMed

Simons, Jack

2008-07-24

The experimental and theoretical study of molecular anions has undergone explosive growth over the past 40 years. Advances in techniques used to generate anions in appreciable numbers as well as new ion-storage, ion-optics, and laser spectroscopic tools have been key on the experimental front. Theoretical developments on the electronic structure and molecular dynamics fronts now allow one to achieve higher accuracy and to study electronically metastable states, thus bringing theory in close collaboration with experiment in this field. In this article, many of the experimental and theoretical challenges specific to studying molecular anions are discussed. Results from many research groups on several classes of molecular anions are overviewed, and both literature citations and active (in online html and pdf versions) links to numerous contributing scientists' Web sites are provided. Specific focus is made on the following families of anions: dipole-bound, zwitterion-bound, double-Rydberg, multiply charged, metastable, cluster-based, and biological anions. In discussing each kind of anion, emphasis is placed on the structural, energetic, spectroscopic, and chemical-reactivity characteristics that make these anions novel, interesting, and important.

Aeropropulsion 1987. Session 2: Aeropropulsion Structures Research

NASA Technical Reports Server (NTRS)

1987-01-01

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

The Biophysics of Infection.

PubMed

Leake, Mark C

2016-01-01

Our understanding of the processes involved in infection has grown enormously in the past decade due in part to emerging methods of biophysics. This new insight has been enabled through advances in interdisciplinary experimental technologies and theoretical methods at the cutting-edge interface of the life and physical sciences. For example, this has involved several state-of-the-art biophysical tools used in conjunction with molecular and cell biology approaches, which enable investigation of infection in living cells. There are also new, emerging interfacial science tools which enable significant improvements to the resolution of quantitative measurements both in space and time. These include single-molecule biophysics methods and super-resolution microscopy approaches. These new technological tools in particular have underpinned much new understanding of dynamic processes of infection at a molecular length scale. Also, there are many valuable advances made recently in theoretical approaches of biophysics which enable advances in predictive modelling to generate new understanding of infection. Here, I discuss these advances, and take stock on our knowledge of the biophysics of infection and discuss where future advances may lead.

A Dialectical Approach to Theoretical Integration in Developmental-Contextual Identity Research

ERIC Educational Resources Information Center

Seaman, Jayson; Sharp, Erin Hiley; Coppens, Andrew D.

2017-01-01

Future advances in identity research will depend on integration across major theoretical traditions. Developmental-contextualism has established essential criteria to guide this effort, including specifying the context of identity development, its timing over the life course, and its content. This article assesses 4 major traditions of identity…

Guiding Empirical and Theoretical Explorations of Organic Matter Decay By Synthesizing Temperature Responses of Enzyme Kinetics, Microbes, and Isotope Fluxes

NASA Astrophysics Data System (ADS)

Billings, S. A.; Ballantyne, F.; Lehmeier, C.; Min, K.

2014-12-01

Soil organic matter (SOM) transformation rates generally increase with temperature, but whether this is realized depends on soil-specific features. To develop predictive models applicable to all soils, we must understand two key, ubiquitous features of SOM transformation: the temperature sensitivity of myriad enzyme-substrate combinations and temperature responses of microbial physiology and metabolism, in isolation from soil-specific conditions. Predicting temperature responses of production of CO2 vs. biomass is also difficult due to soil-specific features: we cannot know the identity of active microbes nor the substrates they employ. We highlight how recent empirical advances describing SOM decay can help develop theoretical tools relevant across diverse spatial and temporal scales. At a molecular level, temperature effects on purified enzyme kinetics reveal distinct temperature sensitivities of decay of diverse SOM substrates. Such data help quantify the influence of microbial adaptations and edaphic conditions on decay, have permitted computation of the relative availability of carbon (C) and nitrogen (N) liberated upon decay, and can be used with recent theoretical advances to predict changes in mass specific respiration rates as microbes maintain biomass C:N with changing temperature. Enhancing system complexity, we can subject microbes to temperature changes while controlling growth rate and without altering substrate availability or identity of the active population, permitting calculation of variables typically inferred in soils: microbial C use efficiency (CUE) and isotopic discrimination during C transformations. Quantified declines in CUE with rising temperature are critical for constraining model CUE estimates, and known changes in δ13C of respired CO2 with temperature is useful for interpreting δ13C-CO2 at diverse scales. We suggest empirical studies important for advancing knowledge of how microbes respond to temperature, and ideas for theoretical work to enhance the relevance of such work to the world's soils.

Autonomous space processor for orbital debris

NASA Technical Reports Server (NTRS)

Ramohalli, Kumar; Campbell, David; Marine, Micky; Saad, Mohamad; Bertles, Daniel; Nichols, Dave

1990-01-01

Advanced designs are being continued to develop the ultimate goal of a GETAWAY special to demonstrate economical removal of orbital debris utilizing local resources in orbit. The fundamental technical feasibility was demonstrated in 1988 through theoretical calculations, quantitative computer animation, a solar focal point cutter, a robotic arm design and a subcase model. Last year improvements were made to the solar cutter and the robotic arm. Also performed last year was a mission analysis which showed the feasibility of retrieve at least four large (greater than 1500 kg) pieces of debris. Advances made during this reporting period are the incorporation of digital control with the existing placement arm, the development of a new robotic manipulator arm, and the study of debris spin attenuation. These advances are discussed.

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

Bemporad, G.A.; Rubin, H.

The development of internal waves and instabilities of the Kelvin Helmholtz-type may prevent the density gradient maintenance which allows the proper functioning of the Advanced Solar Pond (ASP). The properties and characteristics of internal waves, of constant and growing amplitude, are quantitatively described in this paper. The numerical simulations made in this study are in good agreement with previous theoretical and experimental results.

Using the Extended Parallel Process Model to Examine Teachers' Likelihood of Intervening in Bullying

ERIC Educational Resources Information Center

Duong, Jeffrey; Bradshaw, Catherine P.

2013-01-01

Background: Teachers play a critical role in protecting students from harm in schools, but little is known about their attitudes toward addressing problems like bullying. Previous studies have rarely used theoretical frameworks, making it difficult to advance this area of research. Using the Extended Parallel Process Model (EPPM), we examined the…

Feasibility Study on Fully Automatic High Quality Translation: Volume I. Final Technical Report.

ERIC Educational Resources Information Center

Lehmann, Winifred P.; Stachowitz, Rolf

The object of this theoretical inquiry is to examine the controversial issue of a fully automatic high quality translation (FAHQT) in the light of past and projected advances in linguistic theory and hardware/software capability. This first volume of a two-volume report discusses the requirements of translation and aspects of human and machine…

Solid State Cooling with Advanced Oxide Materials

DTIC Science & Technology

2014-06-03

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

Bibliography of Soviet Laser Developments. Number 43, September-October 1979.

DTIC Science & Technology

1980-06-01

Laser Materials, Ultrashort Pulse Generation, X-ray Lasers , Gamma Lasers , Laser Theory, Laser Biological Effects, Laser Communications, Laser ...chemical lasers ; components; nonlinear optics; spectroscopy of laser materials; ultrashort pulse generation; theoretical aspects of advanced lasers ; and...and A.L. Traynin (0). Study on single crystals of shaped germanium, irradiated by a pulsed CO 2 laser .

Harold S. Johnston (1920-2012)

NASA Astrophysics Data System (ADS)

Wuebbles, Donald

2013-02-01

One of the most exceptional atmospheric chemists of the twentieth century, Harold "Hal" S. Johnston died on 20 October 2012 at the age of 92. Hal's pioneering work on atmospheric kinetics, both in laboratory and theoretical studies, greatly advanced understanding of the processes affecting ozone in the troposphere and stratosphere, especially related to the chemistry and impacts resulting from nitrogen oxides (NOx ).

Cross-Cultural Dimensions of Applied, Critical, and Transformational Leadership: Women Principals Advancing Social Justice and Educational Equity

ERIC Educational Resources Information Center

Santamaría, Lorri J.; Jean-Marie, Gaëtane

2014-01-01

This study, based on the qualitatively rendered experiences and perceptions of educational leaders from historically underserved backgrounds in the US, argues that identity impacts leadership practice. To make this point, researchers build upon an emergent theoretical framework for applied critical leadership from the theories and traditions of…

Teaching for Civic Capacity and Engagement: How Faculty Members Align Teaching and Purpose

ERIC Educational Resources Information Center

Domagal-Goldman, Jennifer M.

2010-01-01

Although higher education institutions in the United States have long claimed to teach for civic purposes, only recently have explicit goals related to the development of civic capacity and engagement been included in college and university curricula. The purpose of the study was to advance theoretical and practical understanding of the role of…

Oppenheimer, Julius Robert (1904-67)

NASA Astrophysics Data System (ADS)

Murdin, P.

2000-11-01

Nuclear physicist, born in New York City, joined the Manhattan Project and directed the Los Alamos Laboratory, where he became known as the `father of the atomic bomb'. He directed the Institute for Advanced Studies, Princeton, NJ. He worked on cosmic rays and calculated theoretically the structure of neutron stars, remarking that it seemed unlikely that they existed. Neutron stars were discovere...

A Theoretical Secure Enterprise Architecture for Multi Revenue Generating Smart Grid Sub Electric Infrastructure

ERIC Educational Resources Information Center

Chaudhry, Hina

2013-01-01

This study is a part of the smart grid initiative providing electric vehicle charging infrastructure. It is a refueling structure, an energy generating photovoltaic system and charge point electric vehicle charging station. The system will utilize advanced design and technology allowing electricity to flow from the site's normal electric service…

Relevance and Rigor in International Business Teaching: Using the CSA-FSA Matrix

ERIC Educational Resources Information Center

Collinson, Simon C.; Rugman, Alan M.

2011-01-01

We advance three propositions in this paper. First, teaching international business (IB) at any level needs to be theoretically driven, using mainstream frameworks to organize thinking. Second, these frameworks need to be made relevant to the experiences of the students; for example, by using them in case studies. Third, these parameters of rigor…

PREFACE: Conference of Theoretical Physics and Nonlinear Phenomena (CTPNP) 2014: ''From Universe to String's Scale''

NASA Astrophysics Data System (ADS)

2014-10-01

Theoretical physics is the first step for the development of science and technology. For more than 100 years it has delivered new and sophisticated discoveries which have changed human views of their surroundings and universe. Theoretical physics has also revealed that the governing law in our universe is not deterministic, and it is undoubtedly the foundation of our modern civilization. Contrary to its importance, research in theoretical physics is not well advanced in some developing countries such as Indonesia. This workshop provides the formal meeting in Indonesia devoted to the field of theoretical physics and is organized to cover all subjects of theoretical physics as well as nonlinear phenomena in order to create a gathering place for the theorists in Indonesia and surrounding countries, to motivate young physicists to keep doing active researches in the field and to encourage constructive communication among the community members. Following the success of the tenth previous meetings in this conference series, the eleventh conference was held in Sebelas Maret University (UNS), Surakarta, Indonesia on 15 February 2014. In addition, the conference was proceeded by School of Advance Physics at Gadjah Mada University (UGM), Yogyakarta, on 16-17 February 2014. The conference is expected to provide distinguished experts and students from various research fields of theoretical physics and nonlinear phenomena in Indonesia as well as from other continents the opportunities to present their works and to enhance contacts among them. The introduction to the conference is continued in the pdf.

Combining Advanced Turbulent Mixing and Combustion Models with Advanced Multi-Phase CFD Code to Simulate Detonation and Post-Detonation Bio-Agent Mixing and Destruction

DTIC Science & Technology

2017-10-01

perturbations in the energetic material to study their effects on the blast wave formation. The last case also makes use of the same PBX, however, the...configuration, Case A: Spore cloud located on the top of the charge at an angle 45 degree, Case B: Spore cloud located at an angle 45 degree from the charge...theoretical validation. The first is the Sedov case where the pressure decay and blast wave front are validated based on analytical solutions. In this test

Cognitive correlates of performance in advanced mathematics.

PubMed

Wei, Wei; Yuan, Hongbo; Chen, Chuansheng; Zhou, Xinlin

2012-03-01

Much research has been devoted to understanding cognitive correlates of elementary mathematics performance, but little such research has been done for advanced mathematics (e.g., modern algebra, statistics, and mathematical logic). To promote mathematical knowledge among college students, it is necessary to understand what factors (including cognitive factors) are important for acquiring advanced mathematics. We recruited 80 undergraduates from four universities in Beijing. The current study investigated the associations between students' performance on a test of advanced mathematics and a battery of 17 cognitive tasks on basic numerical processing, complex numerical processing, spatial abilities, language abilities, and general cognitive processing. The results showed that spatial abilities were significantly correlated with performance in advanced mathematics after controlling for other factors. In addition, certain language abilities (i.e., comprehension of words and sentences) also made unique contributions. In contrast, basic numerical processing and computation were generally not correlated with performance in advanced mathematics. Results suggest that spatial abilities and language comprehension, but not basic numerical processing, may play an important role in advanced mathematics. These results are discussed in terms of their theoretical significance and practical implications. ©2011 The British Psychological Society.

Challenges and Opportunities for Research on Same-Sex Relationships

PubMed Central

Umberson, Debra; Thomeer, Mieke Beth; Kroeger, Rhiannon A.; Lodge, Amy Caroline; Xu, Minle

2014-01-01

Research on same-sex relationships has informed policy debates and legal decisions that greatly affect American families, yet the data and methods available to scholars studying same-sex relationships have been limited. In this article the authors review current approaches to studying same-sex relationships and significant challenges for this research. After exploring how researchers have dealt with these challenges in prior studies, the authors discuss promising strategies and methods to advance future research on same-sex relationships, with particular attention given to gendered contexts and dyadic research designs, quasi-experimental designs, and a relationship biography approach. Innovation and advances in the study of same-sex relationships will further theoretical and empirical knowledge in family studies more broadly and increase understanding of different-sex as well as same-sex relationships. PMID:25598552

Maximizing Wellness in Successful Aging and Cancer Coping: The Importance of Family Communication from a Socioemotional Selectivity Theoretical Perspective

PubMed Central

Fisher, Carla L.; Nussbaum, Jon F.

2015-01-01

Interpersonal communication is a fundamental part of being and key to health. Interactions within family are especially critical to wellness across time. Family communication is a central means of adaptation to stress, coping, and successful aging. Still, no theoretical argument in the discipline exists that prioritizes kin communication in health. Theoretical advances can enhance interventions and policies that improve family life. This article explores socioemotional selectivity theory (SST), which highlights communication in our survival. Communication partner choice is based on one's time perspective, which affects our prioritization of goals to survive—goals sought socially. This is a first test of SST in a family communication study on women's health and aging. More than 300 women of varying ages and health status participated. Two time factors, later adulthood and late-stage breast cancer, lead women to prioritize family communication. Findings provide a theoretical basis for prioritizing family communication issues in health reform. PMID:26997920

Maximizing Wellness in Successful Aging and Cancer Coping: The Importance of Family Communication from a Socioemotional Selectivity Theoretical Perspective.

PubMed

Fisher, Carla L; Nussbaum, Jon F

Interpersonal communication is a fundamental part of being and key to health. Interactions within family are especially critical to wellness across time. Family communication is a central means of adaptation to stress, coping, and successful aging. Still, no theoretical argument in the discipline exists that prioritizes kin communication in health. Theoretical advances can enhance interventions and policies that improve family life. This article explores socioemotional selectivity theory (SST), which highlights communication in our survival. Communication partner choice is based on one's time perspective, which affects our prioritization of goals to survive-goals sought socially. This is a first test of SST in a family communication study on women's health and aging. More than 300 women of varying ages and health status participated. Two time factors, later adulthood and late-stage breast cancer, lead women to prioritize family communication. Findings provide a theoretical basis for prioritizing family communication issues in health reform.

Fitness Landscapes of Functional RNAs.

PubMed

Kun, Ádám; Szathmáry, Eörs

2015-08-21

The notion of fitness landscapes, a map between genotype and fitness, was proposed more than 80 years ago. For most of this time data was only available for a few alleles, and thus we had only a restricted view of the whole fitness landscape. Recently, advances in genetics and molecular biology allow a more detailed view of them. Here we review experimental and theoretical studies of fitness landscapes of functional RNAs, especially aptamers and ribozymes. We find that RNA structures can be divided into critical structures, connecting structures, neutral structures and forbidden structures. Such characterisation, coupled with theoretical sequence-to-structure predictions, allows us to construct the whole fitness landscape. Fitness landscapes then can be used to study evolution, and in our case the development of the RNA world.

Gauge interactions theory and experiment

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

Zichichi, A.

This volume brings together physicists from around the world to report and discuss the exciting advances made recently in theoretical and experimental aspects of gauge interactions. Following a presentation of the theoretical foundations of and recent developments in gauge fields, the contrib utors fogus on supersymmetry, the derivation of Higgs particles from gauge fields, and heavy leptons. Other chapters discuss the use of quantum chromodynamics in describing basic interactions among quarks and gluons, in predicting the existence of glueballs, and in application to heavy flavor production in strong interactions. The editor, Antonino Zichichi, provides a study of the multiparticle hadronicmore » systems produced in highenergy soft (pp) interactions. Other interesting chapters deal with photon scattering at very high energies and theoretical alternatives to the electroweak model, and the volume concludes with proposals for future experimental facilities for European physics.« less

Riddles of masculinity: gender, bisexuality, and thirdness.

PubMed

Fogel, Gerald I

2006-01-01

Clinical examples are used to illuminate several riddles of masculinity-ambiguities, enigmas, and paradoxes in relation to gender, bisexuality, and thirdness-frequently seen in male patients. Basic psychoanalytic assumptions about male psychology are examined in the light of advances in female psychology, using ideas from feminist and gender studies as well as important and now widely accepted trends in contemporary psychoanalytic theory. By reexamining basic assumptions about heterosexual men, as has been done with ideas concerning women and homosexual men, complexity and nuance come to the fore to aid the clinician in treating the complex characterological pictures seen in men today. In a context of rapid historical and theoretical change, the use of persistent gender stereotypes and unnecessarily limiting theoretical formulations, though often unintended, may mask subtle countertransference and theoretical blind spots, and limit optimal clinical effectiveness.

Design factors and considerations for a time-based flight management system

NASA Technical Reports Server (NTRS)

Vicroy, D. D.; Williams, D. H.; Sorensen, J. A.

1986-01-01

Recent NASA Langley Research Center research to develop a technology data base from which an advanced Flight Management System (FMS) design might evolve is reviewed. In particular, the generation of fixed range cruise/descent reference trajectories which meet predefined end conditions of altitude, speed, and time is addressed. Results on the design and theoretical basis of the trajectory generation algorithm are presented, followed by a brief discussion of a series of studies that are being conducted to determine the accuracy requirements of the aircraft and weather models resident in the trajectory generation algorithm. Finally, studies to investigate the interface requirements between the pilot and an advanced FMS are considered.

The Future of Theoretical Physics and Cosmology

NASA Astrophysics Data System (ADS)

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

2003-11-01

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

Affective Change in Psychodynamic Psychotherapy: Theoretical Models and Clinical Approaches to Changing Emotions.

PubMed

Subic-Wrana, Claudia; Greenberg, Leslie S; Lane, Richard D; Michal, Matthias; Wiltink, Jörg; Beutel, Manfred E

2016-09-01

Affective change has been considered the hallmark of therapeutic change in psychoanalysis. Psychoanalytic writers have begun to incorporate theoretically the advanced understanding of emotional processing and transformation of the affective neurosciences. We ask if this theoretical advancement is reflected in treatment techniques addressing the processing of emotion. We review psychoanalytic models and treatment recommendations of maladaptive affect processing in the light of a neuroscientifically informed model of achieving psychotherapeutic change by activation and reconsolidation of emotional memory. Emotions tend to be treated as other mental contents, resulting in a lack of specific psychodynamic techniques to work with emotions. Manualized technical modifications addressing affect regulation have been successfully tested in patients with personality pathology, but not for psychodynamic treatments of axis I disorders. Emotional memories need to be activated in order to be modified, therefore, we propose to include techniques into psychodynamic therapy that stimulate emotional experience.

The Role of Identity in Acculturation among Immigrant People: Theoretical Propositions, Empirical Questions, and Applied Recommendations

ERIC Educational Resources Information Center

Schwartz, Seth J.; Montgomery, Marilyn J.; Briones, Ervin

2006-01-01

The present paper advances theoretical propositions regarding the relationship between acculturation and identity. The most central thesis argued is that acculturation represents changes in cultural identity and that personal identity has the potential to "anchor" immigrant people during their transition to a new society. The article emphasizes…

How Do Business and Government Interact? Combining Perspectives from Economics, Political Science, Public Administration, and Practitioners

ERIC Educational Resources Information Center

O'Neill, Patrick B.; Harsell, Dana Michael

2015-01-01

The authors describe the theoretical preparation provided to students in advance of a limited-duration experiential learning experience in Washington DC in a Master's level course for students in Business or Public Administration. The students consider theoretical perspectives from economics, political science, and public administration with…

Advances in Special Education: Volume I. Basic Constructs and Theoretical Orientations. A Research Annual.

ERIC Educational Resources Information Center

Keogh, Barbara K., Ed.

Intended for graduate students in special education, the text presents seven author contributed papers dealing with theoretical issues in the field. M. Faust and W. Faust ("Cognitive Constructing: Levels of Processing and Developmental Change") consider cognitive processing from a developmental perspective. In "Memory Processes in Exceptional…

Models of the Bilingual Lexicon and Their Theoretical Implications for CLIL

ERIC Educational Resources Information Center

Heine, Lena

2014-01-01

Although many advances have been made in recent years concerning the theoretical dimensions of content and language integrated learning (CLIL), research still has to meet the necessity to come up with integrative models that adequately map the interrelation between content and language learning in CLIL contexts. This article will suggest that…

Neuroethics and animals: methods and philosophy.

PubMed

Takala, Tuija; Häyry, Matti

2014-04-01

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

Computational Studies on the Anharmonic Dynamics of Molecular Clusters

NASA Astrophysics Data System (ADS)

Mancini, John S.

Molecular nanoclusters present ideal systems to probe the physical forces and dynamics that drive the behavior of larger bulk systems. At the nanocluster limit the first instances of several phenomena can be observed including the breaking of hydrogen and molecular bonds. Advancements in experimental and theoretical techniques have made it possible to explore these phenomena in great detail. The most fruitful of these studies have involved the use of both experimental and theoretical techniques to leverage to strengths of the two approaches. This dissertation seeks to explore several important phenomena of molecular clusters using new and existing theoretical methodologies. Three specific systems are considered, hydrogen chloride clusters, mixed water and hydrogen chloride clusters and the first cluster where hydrogen chloride autoionization occurs. The focus of these studies remain as close as possible to experimentally observable phenomena with the intention of validating, simulating and expanding on experimental work. Specifically, the properties of interested are those related to the vibrational ground and excited state dynamics of these systems. Studies are performed using full and reduced dimensional potential energy surface alongside advanced quantum mechanical methods including diffusion Monte Carlo, vibrational configuration interaction theory and quasi-classical molecular dynamics. The insight gained from these studies are great and varied. A new on-they-fly ab initio method for studying molecular clusters is validated for (HCl)1--6. A landmark study of the dissociation energy and predissociation mechanism of (HCl)3 is reported. The ground states of mixed (HCl)n(H2O)m are found to be highly delocalized across multiple stationary point configurations. Furthermore, it is identified that the consideration of this delocalization is required in vibrational excited state calculations to achieve agreement with experimental measurements. Finally, the theoretical infrared spectra for the first case of HCl ionization in (H 2O)m is reported, H+(H2O) 3Cl--. The calculation indicates that the ionized cluster's spectra is much more complex than any pervious harmonic predictions, with a large number of the system's infrared active peaks resulting from overtones of lower frequency molecular motions.

View of Soviet ionospheric modification research

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

Duncan, L.M.; Showen, R.L.

1990-10-01

We have reviewed and provided a technical assessment of Soviet research of the past five to ten years in ionospheric modification by high-power radio waves. This review includes a comprehensive survey of Soviet published literature, conference proceedings, and direct discussions with the involved Soviet researchers. The current state of the art for Soviet research in this field is evaluated, identifying areas of potential breakthrough discoveries, and discussing implications of this work for emerging technologies and future applications. This assessment is divided into the categories of basic research, advanced research, and applications. Basic research is further subdivided into studies of themore » modified natural geophysical environment, nonlinear plasma physics, and polar geophysical studies. Advanced research topics include the generation of artificial ionization mirrors and high-power oblique propagation effects. A separate comparative assessment of Soviet theoretical work also is included in this analysis. Our evaluation of practical and potential applications of this research discusses the utility of ionospheric modification in creating disturbed radio wave propagation environments, and its role in current and future remote-sensing and telecommunications systems. This technical assessment does not include consideration of ionospheric modification by means other than high-power radio waves. The Soviet effort in ionospheric modification sustains theoretical and experimental research at activity levels considerably greater than that found in comparable programs in the West. Notable strengths of the Soviet program are its breadth of coverage, large numbers of scientific participation, theoretical creativity and insight, and its powerful radio wave transmitting facilities.« less

Beyond Homophily: A Decade of Advances in Understanding Peer Influence Processes.

PubMed

Brechwald, Whitney A; Prinstein, Mitchell J

2011-03-01

This article reviews empirical and theoretical contributions to a multidisciplinary understanding of peer influence processes in adolescence over the past decade. Five themes of peer influence research from this decade were identified, including a broadening of the range of behaviors for which peer influence occurs, distinguishing the sources of influence, probing the conditions under which influence is amplified/attenuated (moderators), testing theoretically based models of peer influence processes (mechanisms), and preliminary exploration of behavioral neuroscience perspectives on peer influence. This review highlights advances in each of these areas, underscores gaps in current knowledge of peer influence processes, and outlines important challenges for future research.

Beyond Homophily: A Decade of Advances in Understanding Peer Influence Processes

PubMed Central

Brechwald, Whitney A.; Prinstein, Mitchell J.

2013-01-01

This article reviews empirical and theoretical contributions to a multidisciplinary understanding of peer influence processes in adolescence over the past decade. Five themes of peer influence research from this decade were identified, including a broadening of the range of behaviors for which peer influence occurs, distinguishing the sources of influence, probing the conditions under which influence is amplified/attenuated (moderators), testing theoretically based models of peer influence processes (mechanisms), and preliminary exploration of behavioral neuroscience perspectives on peer influence. This review highlights advances in each of these areas, underscores gaps in current knowledge of peer influence processes, and outlines important challenges for future research. PMID:23730122

Defending Against Advanced Persistent Threats Using Game-Theory.

PubMed

Rass, Stefan; König, Sandra; Schauer, Stefan

2017-01-01

Advanced persistent threats (APT) combine a variety of different attack forms ranging from social engineering to technical exploits. The diversity and usual stealthiness of APT turns them into a central problem of contemporary practical system security, since information on attacks, the current system status or the attacker's incentives is often vague, uncertain and in many cases even unavailable. Game theory is a natural approach to model the conflict between the attacker and the defender, and this work investigates a generalized class of matrix games as a risk mitigation tool for an advanced persistent threat (APT) defense. Unlike standard game and decision theory, our model is tailored to capture and handle the full uncertainty that is immanent to APTs, such as disagreement among qualitative expert risk assessments, unknown adversarial incentives and uncertainty about the current system state (in terms of how deeply the attacker may have penetrated into the system's protective shells already). Practically, game-theoretic APT models can be derived straightforwardly from topological vulnerability analysis, together with risk assessments as they are done in common risk management standards like the ISO 31000 family. Theoretically, these models come with different properties than classical game theoretic models, whose technical solution presented in this work may be of independent interest.

Recent advances in the study of gynodioecy: the interface of theory and empiricism.

PubMed

McCauley, David E; Bailey, Maia F

2009-09-01

In this review we report on recent literature concerned with studies of gynodioecy, or the co-occurrence of female and hermaphrodite individuals in natural plant populations. Rather than review this literature in its entirety, our focus is on the interplay between theoretical and empirical approaches to the study of gynodioecy. Five areas of active inquiry are considered. These are the cost of restoration, the influence of population structure on spatial sex-ratio variation, the influence of inbreeding on sex expression, the signature of cyto-nuclear coevolution on the mitochondrial genome, and the consequences of mitochondrial paternal leakage. Recent advances in the study of gynodioecy have been made by considering both the ecology of female:hermaphrodite fitness differences and the genetics of sex expression. Indeed theory has guided empiricism and empiricism has guided theory. Future advances will require that some of the methods currently available only for model organisms be applied to a wider range of species.

Recent advances in the study of gynodioecy: the interface of theory and empiricism

PubMed Central

McCauley, David E.; Bailey, Maia F.

2009-01-01

Background In this review we report on recent literature concerned with studies of gynodioecy, or the co-occurrence of female and hermaphrodite individuals in natural plant populations. Rather than review this literature in its entirety, our focus is on the interplay between theoretical and empirical approaches to the study of gynodioecy. Scope Five areas of active inquiry are considered. These are the cost of restoration, the influence of population structure on spatial sex-ratio variation, the influence of inbreeding on sex expression, the signature of cyto-nuclear coevolution on the mitochondrial genome, and the consequences of mitochondrial paternal leakage. Conclusions Recent advances in the study of gynodioecy have been made by considering both the ecology of female:hermaphrodite fitness differences and the genetics of sex expression. Indeed theory has guided empiricism and empiricism has guided theory. Future advances will require that some of the methods currently available only for model organisms be applied to a wider range of species. PMID:19515690

Metal hydride hydrogen compression: recent advances and future prospects

NASA Astrophysics Data System (ADS)

Yartys, Volodymyr A.; Lototskyy, Mykhaylo; Linkov, Vladimir; Grant, David; Stuart, Alastair; Eriksen, Jon; Denys, Roman; Bowman, Robert C.

2016-04-01

Metal hydride (MH) thermal sorption compression is one of the more important applications of the MHs. The present paper reviews recent advances in the field based on the analysis of the fundamental principles of this technology. The performances when boosting hydrogen pressure, along with two- and three-step compression units, are analyzed. The paper includes also a theoretical modelling of a two-stage compressor aimed at describing the performance of the experimentally studied systems, their optimization and design of more advanced MH compressors. Business developments in the field are reviewed for the Norwegian company HYSTORSYS AS and the South African Institute for Advanced Materials Chemistry. Finally, future prospects are outlined presenting the role of the MH compression in the overall development of the hydrogen-driven energy systems. The work is based on the analysis of the development of the technology in Europe, USA and South Africa.

Metal hydride hydrogen compression: Recent advances and future prospects

DOE PAGES

Bowman, Jr., Robert C.; Yartys, Volodymyr A.; Lototskyy, Mykhaylo V.; ...

2016-03-17

Metal hydride (MH) thermal sorption compression is one of the more important applications of the metal hydrides. The present paper reviews recent advances in the field based on the analysis of the fundamental principles of this technology. The performances when boosting hydrogen pressure, along with two- and three-step compression units are analyzed. The paper includes also a theoretical modeling of a two-stage compressor aimed at both describing the performance of the experimentally studied systems, but, also, on their optimization and design of more advanced MH compressors. Business developments in the field are reviewed for the Norwegian company HYSTORSYS AS andmore » the South African Institute for Advanced Materials Chemistry. Finally, future prospects are outlined presenting the role of the metal hydride compression in the overall development of the hydrogen driven energy systems. Lastly, the work is based on the analysis of the development of the technology in Europe, USA and South Africa.« less

High Gradient Accelerator Research

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

Temkin, Richard

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

Curriculum for the Twenty-First Century: Recent Advances in Economic Theory and Undergraduate Economics

ERIC Educational Resources Information Center

Ferguson, William D.

2011-01-01

Undergraduate economics lags behind cutting-edge economic theory. The author briefly reviews six related advances that profoundly extend and deepen economic analysis: game-theoretic modeling, collective-action problems, information economics and contracting, social preference theory, conceptualizing rationality, and institutional theory. He offers…

Synthesis of a mixed-valent tin nitride and considerations of its possible crystal structures

DOE PAGES

Caskey, Christopher M.; Holder, Aaron; Shulda, Sarah; ...

2016-04-12

Recent advances in theoretical structure prediction methods and high-throughput computational techniques are revolutionizing experimental discovery of the thermodynamically stable inorganic materials. Metastable materials represent a new frontier for these studies, since even simple binary non-ground state compounds of common elements may be awaiting discovery. However, there are significant research challenges related to non-equilibrium thin film synthesis and crystal structure predictions, such as small strained crystals in the experimental samples and energy minimization based theoretical algorithms. Here, we report on experimental synthesis and characterization, as well as theoretical first-principles calculations of a previously unreported mixed-valent binary tin nitride. Thin film experimentsmore » indicate that this novel material is N-deficient SnN with tin in the mixed ii/iv valence state and a small low-symmetry unit cell. Theoretical calculations suggest that the most likely crystal structure has the space group 2 (SG2) related to the distorted delafossite (SG166), which is nearly 0.1 eV/atom above the ground state SnN polymorph. Furthermore, this observation is rationalized by the structural similarity of the SnN distorted delafossite to the chemically related Sn 3N 4 spinel compound, which provides a fresh scientific insight into the reasons for growth of polymorphs of metastable materials. In addition to reporting on the discovery of the simple binary SnN compound, this paper illustrates a possible way of combining a wide range of advanced characterization techniques with the first-principle property calculation methods, to elucidate the most likely crystal structure of the previously unreported metastable materials.« less

Synthesis of a mixed-valent tin nitride and considerations of its possible crystal structures

NASA Astrophysics Data System (ADS)

Caskey, Christopher M.; Holder, Aaron; Shulda, Sarah; Christensen, Steven T.; Diercks, David; Schwartz, Craig P.; Biagioni, David; Nordlund, Dennis; Kukliansky, Alon; Natan, Amir; Prendergast, David; Orvananos, Bernardo; Sun, Wenhao; Zhang, Xiuwen; Ceder, Gerbrand; Ginley, David S.; Tumas, William; Perkins, John D.; Stevanovic, Vladan; Pylypenko, Svitlana; Lany, Stephan; Richards, Ryan M.; Zakutayev, Andriy

2016-04-01

Recent advances in theoretical structure prediction methods and high-throughput computational techniques are revolutionizing experimental discovery of the thermodynamically stable inorganic materials. Metastable materials represent a new frontier for these studies, since even simple binary non-ground state compounds of common elements may be awaiting discovery. However, there are significant research challenges related to non-equilibrium thin film synthesis and crystal structure predictions, such as small strained crystals in the experimental samples and energy minimization based theoretical algorithms. Here, we report on experimental synthesis and characterization, as well as theoretical first-principles calculations of a previously unreported mixed-valent binary tin nitride. Thin film experiments indicate that this novel material is N-deficient SnN with tin in the mixed ii/iv valence state and a small low-symmetry unit cell. Theoretical calculations suggest that the most likely crystal structure has the space group 2 (SG2) related to the distorted delafossite (SG166), which is nearly 0.1 eV/atom above the ground state SnN polymorph. This observation is rationalized by the structural similarity of the SnN distorted delafossite to the chemically related Sn3N4 spinel compound, which provides a fresh scientific insight into the reasons for growth of polymorphs of metastable materials. In addition to reporting on the discovery of the simple binary SnN compound, this paper illustrates a possible way of combining a wide range of advanced characterization techniques with the first-principle property calculation methods, to elucidate the most likely crystal structure of the previously unreported metastable materials.

Synthesis of a mixed-valent tin nitride and considerations of its possible crystal structures.

PubMed

Caskey, Christopher M; Holder, Aaron; Shulda, Sarah; Christensen, Steven T; Diercks, David; Schwartz, Craig P; Biagioni, David; Nordlund, Dennis; Kukliansky, Alon; Natan, Amir; Prendergast, David; Orvananos, Bernardo; Sun, Wenhao; Zhang, Xiuwen; Ceder, Gerbrand; Ginley, David S; Tumas, William; Perkins, John D; Stevanovic, Vladan; Pylypenko, Svitlana; Lany, Stephan; Richards, Ryan M; Zakutayev, Andriy

2016-04-14

Recent advances in theoretical structure prediction methods and high-throughput computational techniques are revolutionizing experimental discovery of the thermodynamically stable inorganic materials. Metastable materials represent a new frontier for these studies, since even simple binary non-ground state compounds of common elements may be awaiting discovery. However, there are significant research challenges related to non-equilibrium thin film synthesis and crystal structure predictions, such as small strained crystals in the experimental samples and energy minimization based theoretical algorithms. Here, we report on experimental synthesis and characterization, as well as theoretical first-principles calculations of a previously unreported mixed-valent binary tin nitride. Thin film experiments indicate that this novel material is N-deficient SnN with tin in the mixed ii/iv valence state and a small low-symmetry unit cell. Theoretical calculations suggest that the most likely crystal structure has the space group 2 (SG2) related to the distorted delafossite (SG166), which is nearly 0.1 eV/atom above the ground state SnN polymorph. This observation is rationalized by the structural similarity of the SnN distorted delafossite to the chemically related Sn3N4 spinel compound, which provides a fresh scientific insight into the reasons for growth of polymorphs of metastable materials. In addition to reporting on the discovery of the simple binary SnN compound, this paper illustrates a possible way of combining a wide range of advanced characterization techniques with the first-principle property calculation methods, to elucidate the most likely crystal structure of the previously unreported metastable materials.

Synthesis of a mixed-valent tin nitride and considerations of its possible crystal structures

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

Caskey, Christopher M.; Colorado School of Mines, Golden, Colorado 80401; Larix Chemical Science, Golden, Colorado 80401

2016-04-14

Recent advances in theoretical structure prediction methods and high-throughput computational techniques are revolutionizing experimental discovery of the thermodynamically stable inorganic materials. Metastable materials represent a new frontier for these studies, since even simple binary non-ground state compounds of common elements may be awaiting discovery. However, there are significant research challenges related to non-equilibrium thin film synthesis and crystal structure predictions, such as small strained crystals in the experimental samples and energy minimization based theoretical algorithms. Here, we report on experimental synthesis and characterization, as well as theoretical first-principles calculations of a previously unreported mixed-valent binary tin nitride. Thin film experimentsmore » indicate that this novel material is N-deficient SnN with tin in the mixed II/IV valence state and a small low-symmetry unit cell. Theoretical calculations suggest that the most likely crystal structure has the space group 2 (SG2) related to the distorted delafossite (SG166), which is nearly 0.1 eV/atom above the ground state SnN polymorph. This observation is rationalized by the structural similarity of the SnN distorted delafossite to the chemically related Sn{sub 3}N{sub 4} spinel compound, which provides a fresh scientific insight into the reasons for growth of polymorphs of metastable materials. In addition to reporting on the discovery of the simple binary SnN compound, this paper illustrates a possible way of combining a wide range of advanced characterization techniques with the first-principle property calculation methods, to elucidate the most likely crystal structure of the previously unreported metastable materials.« less

Review of Aircraft Crash Structural Response Research.

DTIC Science & Technology

1982-08-01

structures consisting of conventional built-up metallic construction and those consisting of advanced composite materials were of interest. The latter...increasing importance. Some recent theoretical and experimental studies of the behavior of composite - material structures subjected to severe static...dynamic, and/or impact conditions are noted. Such topics as crashworthiness testing ot composite fuselage structures, the impact resistance of graphite and

Conceptualization of an Innovative Educational Taxonomy for the 21st Century Learners

ERIC Educational Resources Information Center

V, Viji; Benedict, K. Y.

2017-01-01

The key purpose of this study was to design and develop a new taxonomy of educational objectives for the 21st century learners; in view of the recent theoretical perspectives, needs of learners, value-based education and the up-to-date technological advancements, in order to accustom to the distinct educational and cultural milieus in India. This…

500 Maori PhDs in Five Years: Insights from a Successful Indigenous Higher Education Initiative

ERIC Educational Resources Information Center

Villegas, Malia Maya

2010-01-01

With this thesis, I present a case study of the effort to graduate 500 "Maori" doctorates in five years in New Zealand in order to advance our understanding of a successful Indigenous higher education initiative. By paying careful attention to contextual factors, I describe the theoretical and practical significance of this effort and…

Creating an advance-care-planning decision aid for high-risk surgery: a qualitative study

PubMed Central

2014-01-01

Background High-risk surgery patients may lose decision-making capacity as a result of surgical complications. Advance care planning prior to surgery may be beneficial, but remains controversial and is hindered by a lack of appropriate decision aids. This study sought to examine stakeholders’ views on the appropriateness of using decision aids, in general, to support advance care planning among high-risk surgery populations and the design of such a decision aid. Methods Key informants were recruited through purposive and snowball sampling. Semi-structured interviews were conducted by phone until data collected reached theoretical saturation. Key informants were asked to discuss their thoughts about advance care planning and interventions to support advance care planning, particularly for this population. Researchers took de-identified notes that were analyzed for emerging concordant, discordant, and recurrent themes using interpretative phenomenological analysis. Results Key informants described the importance of initiating advance care planning preoperatively, despite potential challenges present in surgical settings. In general, decision aids were viewed as an appropriate approach to support advance care planning for this population. A recipe emerged from the data that outlines tools, ingredients, and tips for success that are needed to design an advance care planning decision aid for high-risk surgical settings. Conclusions Stakeholders supported incorporating advance care planning in high-risk surgical settings and endorsed the appropriateness of using decision aids to do so. Findings will inform the next stages of developing the first advance care planning decision aid for high-risk surgery patients. PMID:25067908

Creating an advance-care-planning decision aid for high-risk surgery: a qualitative study.

PubMed

Schuster, Anne Lr; Aslakson, Rebecca A; Bridges, John Fp

2014-01-01

High-risk surgery patients may lose decision-making capacity as a result of surgical complications. Advance care planning prior to surgery may be beneficial, but remains controversial and is hindered by a lack of appropriate decision aids. This study sought to examine stakeholders' views on the appropriateness of using decision aids, in general, to support advance care planning among high-risk surgery populations and the design of such a decision aid. Key informants were recruited through purposive and snowball sampling. Semi-structured interviews were conducted by phone until data collected reached theoretical saturation. Key informants were asked to discuss their thoughts about advance care planning and interventions to support advance care planning, particularly for this population. Researchers took de-identified notes that were analyzed for emerging concordant, discordant, and recurrent themes using interpretative phenomenological analysis. Key informants described the importance of initiating advance care planning preoperatively, despite potential challenges present in surgical settings. In general, decision aids were viewed as an appropriate approach to support advance care planning for this population. A recipe emerged from the data that outlines tools, ingredients, and tips for success that are needed to design an advance care planning decision aid for high-risk surgical settings. Stakeholders supported incorporating advance care planning in high-risk surgical settings and endorsed the appropriateness of using decision aids to do so. Findings will inform the next stages of developing the first advance care planning decision aid for high-risk surgery patients.

Research in the Aloha system

NASA Technical Reports Server (NTRS)

Abramson, N.

1974-01-01

The Aloha system was studied and developed and extended to advanced forms of computer communications networks. Theoretical and simulation studies of Aloha type radio channels for use in packet switched communications networks were performed. Improved versions of the Aloha communications techniques and their extensions were tested experimentally. A packet radio repeater suitable for use with the Aloha system operational network was developed. General studies of the organization of multiprocessor systems centered on the development of the BCC 500 computer were concluded.

Quantum memories: emerging applications and recent advances

NASA Astrophysics Data System (ADS)

Heshami, Khabat; England, Duncan G.; Humphreys, Peter C.; Bustard, Philip J.; Acosta, Victor M.; Nunn, Joshua; Sussman, Benjamin J.

2016-11-01

Quantum light-matter interfaces are at the heart of photonic quantum technologies. Quantum memories for photons, where non-classical states of photons are mapped onto stationary matter states and preserved for subsequent retrieval, are technical realizations enabled by exquisite control over interactions between light and matter. The ability of quantum memories to synchronize probabilistic events makes them a key component in quantum repeaters and quantum computation based on linear optics. This critical feature has motivated many groups to dedicate theoretical and experimental research to develop quantum memory devices. In recent years, exciting new applications, and more advanced developments of quantum memories, have proliferated. In this review, we outline some of the emerging applications of quantum memories in optical signal processing, quantum computation and non-linear optics. We review recent experimental and theoretical developments, and their impacts on more advanced photonic quantum technologies based on quantum memories.

Quantum memories: emerging applications and recent advances.

PubMed

Heshami, Khabat; England, Duncan G; Humphreys, Peter C; Bustard, Philip J; Acosta, Victor M; Nunn, Joshua; Sussman, Benjamin J

2016-11-12

Quantum light-matter interfaces are at the heart of photonic quantum technologies. Quantum memories for photons, where non-classical states of photons are mapped onto stationary matter states and preserved for subsequent retrieval, are technical realizations enabled by exquisite control over interactions between light and matter. The ability of quantum memories to synchronize probabilistic events makes them a key component in quantum repeaters and quantum computation based on linear optics. This critical feature has motivated many groups to dedicate theoretical and experimental research to develop quantum memory devices. In recent years, exciting new applications, and more advanced developments of quantum memories, have proliferated. In this review, we outline some of the emerging applications of quantum memories in optical signal processing, quantum computation and non-linear optics. We review recent experimental and theoretical developments, and their impacts on more advanced photonic quantum technologies based on quantum memories.

Quantum memories: emerging applications and recent advances

PubMed Central

Heshami, Khabat; England, Duncan G.; Humphreys, Peter C.; Bustard, Philip J.; Acosta, Victor M.; Nunn, Joshua; Sussman, Benjamin J.

2016-01-01

Quantum light–matter interfaces are at the heart of photonic quantum technologies. Quantum memories for photons, where non-classical states of photons are mapped onto stationary matter states and preserved for subsequent retrieval, are technical realizations enabled by exquisite control over interactions between light and matter. The ability of quantum memories to synchronize probabilistic events makes them a key component in quantum repeaters and quantum computation based on linear optics. This critical feature has motivated many groups to dedicate theoretical and experimental research to develop quantum memory devices. In recent years, exciting new applications, and more advanced developments of quantum memories, have proliferated. In this review, we outline some of the emerging applications of quantum memories in optical signal processing, quantum computation and non-linear optics. We review recent experimental and theoretical developments, and their impacts on more advanced photonic quantum technologies based on quantum memories. PMID:27695198

Autonomy, liberalism and advance care planning.

PubMed Central

Ikonomidis, S; Singer, P A

1999-01-01

The justification for advance directives is grounded in the notion that they extend patient autonomy into future states of incompetency through patient participation in decision making about end-of-life care. Four objections challenge the necessity and sufficiency of individual autonomy, perceived to be a defining feature of liberal philosophical theory, as a basis of advance care planning. These objections are that the liberal concept of autonomy (i) implies a misconception of the individual self, (ii) entails the denial of values of social justice, (iii) does not account for justifiable acts of paternalism, and (iv) does not account for the importance of personal relationships in the advance care planning process. The last objection is especially pertinent in light of recent empirical research highlighting the importance of personal relationships in advance care planning. This article examines these four objections to autonomy, and the liberal theoretical framework with which it is associated, in order to re-evaluate the philosophical basis of advance care planning. We argue that liberal autonomy (i) is not a misconceived concept as critics assume, (ii) does not entail the denial of values of social justice, (iii) can account for justifiable acts of paternalism, though it (iv) is not the best account of the value of personal relationships that arise in advance care planning. In conclusion, we suggest that liberalism is a necessary component of a theoretical framework for advance care planning but that it needs to be supplemented with theories that focus explicitly on the significance of personal relationships. PMID:10635509

Autonomous space processor for orbital debris

NASA Technical Reports Server (NTRS)

1990-01-01

This work continues to develop advanced designs toward the ultimate goal of a Get Away Special to demonstrate economical removal of orbital debris using local resources in orbit. The fundamental technical feasibility was demonstrated in 1988 through theoretical calculations, quantitative computer animation, a solar focal point cutter, a robotic arm design, and a subscale model. Last year improvements were made to the solar cutter and the robotic arm. Also performed last year was a mission analysis that showed the feasibility of retrieving at least four large (greater than 1500-kg) pieces of debris. Advances made during this reporting period are the incorporation of digital control with the existing placement arm, the development of a new robotic manipulator arm, and the study of debris spin attenuation. These advances are discussed here.

Understanding dopamine and reinforcement learning: the dopamine reward prediction error hypothesis.

PubMed

Glimcher, Paul W

2011-09-13

A number of recent advances have been achieved in the study of midbrain dopaminergic neurons. Understanding these advances and how they relate to one another requires a deep understanding of the computational models that serve as an explanatory framework and guide ongoing experimental inquiry. This intertwining of theory and experiment now suggests very clearly that the phasic activity of the midbrain dopamine neurons provides a global mechanism for synaptic modification. These synaptic modifications, in turn, provide the mechanistic underpinning for a specific class of reinforcement learning mechanisms that now seem to underlie much of human and animal behavior. This review describes both the critical empirical findings that are at the root of this conclusion and the fantastic theoretical advances from which this conclusion is drawn.

Understanding dopamine and reinforcement learning: The dopamine reward prediction error hypothesis

PubMed Central

Glimcher, Paul W.

2011-01-01

A number of recent advances have been achieved in the study of midbrain dopaminergic neurons. Understanding these advances and how they relate to one another requires a deep understanding of the computational models that serve as an explanatory framework and guide ongoing experimental inquiry. This intertwining of theory and experiment now suggests very clearly that the phasic activity of the midbrain dopamine neurons provides a global mechanism for synaptic modification. These synaptic modifications, in turn, provide the mechanistic underpinning for a specific class of reinforcement learning mechanisms that now seem to underlie much of human and animal behavior. This review describes both the critical empirical findings that are at the root of this conclusion and the fantastic theoretical advances from which this conclusion is drawn. PMID:21389268

The principal components model: a model for advancing spirituality and spiritual care within nursing and health care practice.

PubMed

McSherry, Wilfred

2006-07-01

The aim of this study was to generate a deeper understanding of the factors and forces that may inhibit or advance the concepts of spirituality and spiritual care within both nursing and health care. This manuscript presents a model that emerged from a qualitative study using grounded theory. Implementation and use of this model may assist all health care practitioners and organizations to advance the concepts of spirituality and spiritual care within their own sphere of practice. The model has been termed the principal components model because participants identified six components as being crucial to the advancement of spiritual health care. Grounded theory was used meaning that there was concurrent data collection and analysis. Theoretical sampling was used to develop the emerging theory. These processes, along with data analysis, open, axial and theoretical coding led to the identification of a core category and the construction of the principal components model. Fifty-three participants (24 men and 29 women) were recruited and all consented to be interviewed. The sample included nurses (n=24), chaplains (n=7), a social worker (n=1), an occupational therapist (n=1), physiotherapists (n=2), patients (n=14) and the public (n=4). The investigation was conducted in three phases to substantiate the emerging theory and the development of the model. The principal components model contained six components: individuality, inclusivity, integrated, inter/intra-disciplinary, innate and institution. A great deal has been written on the concepts of spirituality and spiritual care. However, rhetoric alone will not remove some of the intrinsic and extrinsic barriers that are inhibiting the advancement of the spiritual dimension in terms of theory and practice. An awareness of and adherence to the principal components model may assist nurses and health care professionals to engage with and overcome some of the structural, organizational, political and social variables that are impacting upon spiritual care.

In Silico Pharmacophore Model for Tabun-Inhibites Acetylcholinesterase Reactivators: A study of Their Stereoelectronic Properties

DTIC Science & Technology

2009-01-01

Army Institute of Research, 503 Robert Grant AVenue, SilVer Spring, Maryland 20910, and Center for AdVanced Studies and Department of Toxicology ...Department of Toxicology , Faculty of Military Health Sciences. Chem. Res. Toxicol. XXXX, , 000 A 10.1021/tx900192u  XXXX American Chemical Society...GA-inhibited AChE derived from theoretical stereoelectronic and three-dimensional (3D) quantitative struc- ture-activity relationship ( QSAR

E=mc2 in theory and in practice

NASA Astrophysics Data System (ADS)

Friedlander, Michael W.

2009-02-01

Einstein and Oppenheimer are forever linked by that famous equation. Einstein derived it and Oppenheimer oversaw its terrible application. The Meaning of Genius is the subtitle that Silvan Schweber has chosen for his study of these two very different giants. Schweber is a theoretical physicist whose years at the Institute for Advanced Study in Princeton overlapped with those of Einstein and Oppenheimer, for whom he provides a perceptive comparison in his book's introductory chapter.

Advanced classical thermodynamics

NASA Astrophysics Data System (ADS)

Emanuel, George

The theoretical and mathematical foundations of thermodynamics are presented in an advanced text intended for graduate engineering students. Chapters are devoted to definitions and postulates, the fundamental equation, equilibrium, the application of Jacobian theory to thermodynamics, the Maxwell equations, stability, the theory of real gases, critical-point theory, and chemical thermodynamics. Diagrams, graphs, tables, and sample problems are provided.

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

ERIC Educational Resources Information Center

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

2012-01-01

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

Cost estimating methods for advanced space systems

NASA Technical Reports Server (NTRS)

Cyr, Kelley

1988-01-01

The development of parametric cost estimating methods for advanced space systems in the conceptual design phase is discussed. The process of identifying variables which drive cost and the relationship between weight and cost are discussed. A theoretical model of cost is developed and tested using a historical data base of research and development projects.

Venturing into the Unknown: Blogs as a Means of Advancing Leadership Skills

ERIC Educational Resources Information Center

Kodish, Slavica

2017-01-01

The author describes a theoretically eclectic exploratory assignment that helped students in a managerial communication class practice and advance a comprehensive range of leadership skills. Specifically, the author combined E. M. Eisenberg, L. H. Goodall, and A. Tretheway's (2014) model of leadership with pertinent concepts from the theory of…

Experiencing Philosophy: Engaging Students in Advanced Theory

ERIC Educational Resources Information Center

Blenkinsop, Sean; Beeman, Chris

2012-01-01

In this paper, we will argue, predominantly using examples tested in the crucible of our own teaching, that there is a place for experiential education in the teaching of advanced theoretical ideas. As experiential educators trained as philosophers of education and working in faculties of education, we regularly encounter students with little or…

Exploring a Century of Advancements in the Science of Learning

ERIC Educational Resources Information Center

Murphy, P. Karen; Knight, Stephanie L.

2016-01-01

The past century has yielded a plethora of advancements in the science of learning, from expansions in the theoretical frames that undergird education research to cultural and contextual considerations in educational practice. The overarching purpose of this chapter is to explore and document the growth and development of the science of learning…

Some issues for blast from a structural reactive material solid

NASA Astrophysics Data System (ADS)

Zhang, F.

2018-07-01

Structural reactive material (SRM) is consolidated from a mixture of micro- or nanometric reactive metals and metal compounds to the mixture theoretical maximum density. An SRM can thus possess a higher energy density, relying on various exothermic reactions, and higher mechanical strength and heat resistance than that of conventional CHNO explosives. Progress in SRM solid studies is reviewed specifically as an energy source for air blast through the reaction of fine SRM fragments under explosive loading. This includes a baseline SRM solid explosion characterization, material properties of an SRM solid, and its dynamic fine fragmentation mechanisms and fragment reaction mechanisms. The overview is portrayed mainly from the author's own experimental studies combined with theoretical and numerical explanation. These advances have laid down some fundamentals for the next stage of developments.

Some issues for blast from a structural reactive material solid

NASA Astrophysics Data System (ADS)

Zhang, F.

2018-03-01

Structural reactive material (SRM) is consolidated from a mixture of micro- or nanometric reactive metals and metal compounds to the mixture theoretical maximum density. An SRM can thus possess a higher energy density, relying on various exothermic reactions, and higher mechanical strength and heat resistance than that of conventional CHNO explosives. Progress in SRM solid studies is reviewed specifically as an energy source for air blast through the reaction of fine SRM fragments under explosive loading. This includes a baseline SRM solid explosion characterization, material properties of an SRM solid, and its dynamic fine fragmentation mechanisms and fragment reaction mechanisms. The overview is portrayed mainly from the author's own experimental studies combined with theoretical and numerical explanation. These advances have laid down some fundamentals for the next stage of developments.

Problematics of Time and Timing in the Longitudinal Study of Human Development: Theoretical and Methodological Issues

PubMed Central

Lerner, Richard M.; Schwartz, Seth J; Phelps, Erin

2009-01-01

Studying human development involves describing, explaining, and optimizing intraindividual change and interindividual differences in such change and, as such, requires longitudinal research. The selection of the appropriate type of longitudinal design requires selecting the option that best addresses the theoretical questions asked about developmental process and the use of appropriate statistical procedures to best exploit data derived from theory-predicated longitudinal research. This paper focuses on several interrelated problematics involving the treatment of time and the timing of observations that developmental scientists face in creating theory-design fit and in charting in change-sensitive ways developmental processes across life. We discuss ways in which these problematics may be addressed to advance theory-predicated understanding of the role of time in processes of individual development. PMID:19554215

Consciousness Regained: Disentangling Mechanisms, Brain Systems, and Behavioral Responses

PubMed Central

2017-01-01

How consciousness (experience) arises from and relates to material brain processes (the “mind-body problem”) has been pondered by thinkers for centuries, and is regarded as among the deepest unsolved problems in science, with wide-ranging theoretical, clinical, and ethical implications. Until the last few decades, this was largely seen as a philosophical topic, but not widely accepted in mainstream neuroscience. Since the 1980s, however, novel methods and theoretical advances have yielded remarkable results, opening up the field for scientific and clinical progress. Since a seminal paper by Crick and Koch (1998) claimed that a science of consciousness should first search for its neural correlates (NCC), a variety of correlates have been suggested, including both content-specific NCCs, determining particular phenomenal components within an experience, and the full NCC, the neural substrates supporting entire conscious experiences. In this review, we present recent progress on theoretical, experimental, and clinical issues. Specifically, we (1) review methodological advances that are important for dissociating conscious experience from related enabling and executive functions, (2) suggest how critically reconsidering the role of the frontal cortex may further delineate NCCs, (3) advocate the need for general, objective, brain-based measures of the capacity for consciousness that are independent of sensory processing and executive functions, and (4) show how animal studies can reveal population and network phenomena of relevance for understanding mechanisms of consciousness. PMID:29118218

Review of sonic fatigue technology

NASA Technical Reports Server (NTRS)

Clarkson, B. L.

1994-01-01

From the early-1960s until the mid-1980s, there was very little theoretical development for sonic fatigue prediction. Design nomographs based on simple theoretical models and results of specially designed tests were developed for most common aircraft structures. The use of advanced composites in the 1980s, however, generated an increased interest in development of more sophisticated theoretical models because of the possibilities for a much wider range of structural designs. The purpose of this report is to review sonic fatigue technology and, in particular, to assess recent developments. It also suggests a plan for a coordinated program of theoretical and experimental work to meet the anticipated needs of future aerospace vehicles.

Advanced rechargeable sodium batteries with novel cathodes

NASA Technical Reports Server (NTRS)

Distefano, S.; Ratnakumar, B. V.; Bankston, C. P.

1989-01-01

Various high energy density rechargeable batteries are being considered for future space applications. Of these, the sodium sulfur battery is one of the leading candidates. The primary advantage is the high energy density (760 Wh/kg theoretical). Energy densities in excess of 180 Wh/kg have been realized in practical batteries. More recently, cathodes other than sulfur are being evaluated. Researchers at JPL are evaluating various new cathode materials for use in high energy density sodium batteries for advanced space applications. The approach is to carry out basic electrochemical studies of these materials in a sodium cell configuration in order to understand their fundamental behaviors. Thus far studies have focused on alternate metal chlorides such as CuCl2 and organic cathode materials such as tetracyanoethylene (TCNE).

Advanced rechargeable sodium batteries with novel cathodes

NASA Technical Reports Server (NTRS)

Di Stefano, S.; Ratnakumar, B. V.; Bankston, C. P.

1990-01-01

Various high energy density rechargeable batteries are being considered for future space applications. Of these, the sodium-sulfur battery is one of the leading candidates. The primary advantage is the high energy density (760 W h/kg theoretical). Energy densities in excess of 180 W h/kg have been realized in practical batteries. More recently, cathodes other than sulfur are being evaluated. Various new cathode materials are presently being evaluated for use in high energy density sodium batteries for advanced space applications. The approach is to carry out basic electrochemical studies of these materials in a sodium cell configuration in order to understand their fundamental behaviors. Thus far, the studies have focussed on alternative metal chlorides such as CuCl2 and organic cathode materials such as TCNE.

Synthesis of borophenes: Anisotropic, two-dimensional boron polymorphs.

PubMed

Mannix, Andrew J; Zhou, Xiang-Feng; Kiraly, Brian; Wood, Joshua D; Alducin, Diego; Myers, Benjamin D; Liu, Xiaolong; Fisher, Brandon L; Santiago, Ulises; Guest, Jeffrey R; Yacaman, Miguel Jose; Ponce, Arturo; Oganov, Artem R; Hersam, Mark C; Guisinger, Nathan P

2015-12-18

At the atomic-cluster scale, pure boron is markedly similar to carbon, forming simple planar molecules and cage-like fullerenes. Theoretical studies predict that two-dimensional (2D) boron sheets will adopt an atomic configuration similar to that of boron atomic clusters. We synthesized atomically thin, crystalline 2D boron sheets (i.e., borophene) on silver surfaces under ultrahigh-vacuum conditions. Atomic-scale characterization, supported by theoretical calculations, revealed structures reminiscent of fused boron clusters with multiple scales of anisotropic, out-of-plane buckling. Unlike bulk boron allotropes, borophene shows metallic characteristics that are consistent with predictions of a highly anisotropic, 2D metal. Copyright © 2015, American Association for the Advancement of Science.

Theoretical and Methodological Considerations in Cross-Generational Research on Parenting and Child Aggressive Behavior

PubMed Central

Dubow, Eric F.; Huesmann, L. Rowell; Boxer, Paul

2015-01-01

The four studies in this special issue represent important advances in research on the intergenerational transmission of aggressive behavior. In this commentary, we review the key features and findings of these studies, as well as our own cross-generational study of aggression, the Columbia County Longitudinal Study. Next, we consider important theoretical issues (e.g., defining and operationalizing “aggression” and “parenting”; assessing reciprocal effects of parenting and child aggression; identifying the ages at which aggression should be assessed across generations; broadening the investigation of contextual and individual factors). We then discuss several methodological issues (e.g., determining the most informative measurement intervals for assessing prospective effects; sampling considerations; measuring potential moderating and mediating variables that might explain cross-generational continuities and discontinuities in parenting and aggression). Finally, we raise implications of cross-generational research for designing interventions targeting the reduction and prevention of child aggression. PMID:12735400

Advance care treatment plan (ACT-Plan) for African American family caregivers: a pilot study.

PubMed

Bonner, Gloria J; Wang, Edward; Wilkie, Diana J; Ferrans, Carol E; Dancy, Barbara; Watkins, Yashika

2014-01-01

Research is limited on end-of-life treatment decisions made by African American family caregivers. In a pilot study, we examined the feasibility of implementing an advance care treatment plan (ACT-Plan), a group-based education intervention, with African American dementia caregivers. Theoretically based, the ACT-Plan included strategies to enhance knowledge, self-efficacy, and behavioral skills to make end-of-life treatment plans in advance. Cardiopulmonary resuscitation, mechanical ventilation, and tube feeding were end-of-life treatments discussed in the ACT-Plan. In a four-week pre/posttest two-group design at urban adult day care centers, 68 caregivers were assigned to the ACT-Plan or attention-control health promotion conditions. Findings strongly suggest that the ACT-Plan intervention is feasible and appropriate for African American caregivers. Self-efficacy and knowledge about dementia, cardiopulmonary resuscitation, mechanical ventilation, and tube feeding increased for ACT-Plan participants but not for the attention-control. More ACT-Plan than attention-control participants developed advance care plans for demented relatives. Findings warrant a randomized efficacy trial.

Defending Against Advanced Persistent Threats Using Game-Theory

PubMed Central

König, Sandra; Schauer, Stefan

2017-01-01

Advanced persistent threats (APT) combine a variety of different attack forms ranging from social engineering to technical exploits. The diversity and usual stealthiness of APT turns them into a central problem of contemporary practical system security, since information on attacks, the current system status or the attacker’s incentives is often vague, uncertain and in many cases even unavailable. Game theory is a natural approach to model the conflict between the attacker and the defender, and this work investigates a generalized class of matrix games as a risk mitigation tool for an advanced persistent threat (APT) defense. Unlike standard game and decision theory, our model is tailored to capture and handle the full uncertainty that is immanent to APTs, such as disagreement among qualitative expert risk assessments, unknown adversarial incentives and uncertainty about the current system state (in terms of how deeply the attacker may have penetrated into the system’s protective shells already). Practically, game-theoretic APT models can be derived straightforwardly from topological vulnerability analysis, together with risk assessments as they are done in common risk management standards like the ISO 31000 family. Theoretically, these models come with different properties than classical game theoretic models, whose technical solution presented in this work may be of independent interest. PMID:28045922

Advanced theoretical and experimental studies in automatic control and information systems. [including mathematical programming and game theory

NASA Technical Reports Server (NTRS)

Desoer, C. A.; Polak, E.; Zadeh, L. A.

1974-01-01

A series of research projects is briefly summarized which includes investigations in the following areas: (1) mathematical programming problems for large system and infinite-dimensional spaces, (2) bounded-input bounded-output stability, (3) non-parametric approximations, and (4) differential games. A list of reports and papers which were published over the ten year period of research is included.

Methods of Study in Soil Ecology, Proceedings of the Symposium Organized by Unesco and the International Biological Programme (Paris, France, November, 1967).

ERIC Educational Resources Information Center

Phillipson, J., Ed.

Included are papers (in French or English, with summaries in the other language) presented at a UNESCO-International Biological Programme symposium in 1967. The symposium provided an opportunity for the exchange of information on recent advances in soil ecology, with particular emphasis on soil productivity. Papers on broader theoretical aspects…

Transplant rejection and tolerance – advancing the field through integration of computational and experimental investigation

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

Raimondi, Giorgio; Wood, Kathryn; Perelson, Alan S.

This Research Topic provides a venue for stimulating these interdisciplinary conversations in the context of transplantation. The articles collected under this Research Topic introduce new theoretical and experimental studies that describe novel techniques and methods for understanding the interactions between the immune response and transplants and for establishing more effective strategies of diagnosis and intervention that will promote transplant tolerance.

Theoretical Studies of Ionic Liquids and Nanoclusters as Hybrid Fuels

DTIC Science & Technology

2016-08-17

Acknowledgements Distribution A: Approved for Public Release; Distribution Unlimited. PA# 16409 Aerospace Systems Directorate RQ-West (EAFB, CA)  Rocket ...Engines & Motors  Satellite Propulsion  Combustion Devices  Fuels and Propellants  System Analysis  R&D Rocket Testing RQ-East (WPAFB, OH)  Air...Distribution A: Approved for Public Release; Distribution Unlimited. PA# 16409 5 Identify and develop advanced chemical propellants for rocket

Mono- and binuclear non-heme iron chemistry from a theoretical perspective.

PubMed

Rokob, Tibor András; Chalupský, Jakub; Bím, Daniel; Andrikopoulos, Prokopis C; Srnec, Martin; Rulíšek, Lubomír

2016-09-01

In this minireview, we provide an account of the current state-of-the-art developments in the area of mono- and binuclear non-heme enzymes (NHFe and NHFe2) and the smaller NHFe(2) synthetic models, mostly from a theoretical and computational perspective. The sheer complexity, and at the same time the beauty, of the NHFe(2) world represents a challenge for experimental as well as theoretical methods. We emphasize that the concerted progress on both theoretical and experimental side is a conditio sine qua non for future understanding, exploration and utilization of the NHFe(2) systems. After briefly discussing the current challenges and advances in the computational methodology, we review the recent spectroscopic and computational studies of NHFe(2) enzymatic and inorganic systems and highlight the correlations between various experimental data (spectroscopic, kinetic, thermodynamic, electrochemical) and computations. Throughout, we attempt to keep in mind the most fascinating and attractive phenomenon in the NHFe(2) chemistry, which is the fact that despite the strong oxidative power of many reactive intermediates, the NHFe(2) enzymes perform catalysis with high selectivity. We conclude with our personal viewpoint and hope that further developments in quantum chemistry and especially in the field of multireference wave function methods are needed to have a solid theoretical basis for the NHFe(2) studies, mostly by providing benchmarking and calibration of the computationally efficient and easy-to-use DFT methods.

A revised Self- and Family Management Framework.

PubMed

Grey, Margaret; Schulman-Green, Dena; Knafl, Kathleen; Reynolds, Nancy R

2015-01-01

Research on self- and family management of chronic conditions has advanced over the past 6 years, but the use of simple frameworks has hampered the understanding of the complexities involved. We sought to update our previously published model with new empirical, synthetic, and theoretical work. We used synthesis of previous studies to update the framework. We propose a revised framework that clarifies facilitators and barriers, processes, proximal outcomes, and distal outcomes of self- and family management and their relationships. We offer the revised framework as a model that can be used in studies aimed at advancing self- and family management science. The use of the framework to guide studies would allow for the design of studies that can address more clearly how self-management interventions work and under what conditions. Copyright © 2015 Elsevier Inc. All rights reserved.

Novel Magnetic Devices

DTIC Science & Technology

2007-10-12

Vincent, Magnetism Magnetic Materials (LAW3MO5), Vifia del Mar, Chile, December 11-15, 2005. 5. Nanomagnetism, Ivan K. Schuller, Pan America Advanced Study Institute, PASI 2007, Zacatecas , Mexico , June 19, 2007. 6 ...project explored the design, preparation, measurement and theoretical study of these novel magnetic devices. Modem thin film techniques (sputtering and...results to motion associated with the unstable nature of mechanical contacts In order to exploit BMR from a device point of view (or to make it useful in a

Systematic review of psychosocial outcomes for patients with advanced melanoma.

PubMed

Dunn, Jeff; Watson, Maggie; Aitken, Joanne F; Hyde, Melissa K

2017-11-01

New advanced melanoma therapies are associated with improved survival; however, quality of survivorship, particularly psychosocial outcomes, for patients overall and those treated with newer therapies is unclear. Synthesize qualitative and quantitative evidence about psychosocial outcomes for advanced (stage III/IV) melanoma patients. Five databases were searched (01/01/1980 to 31/01/2016). Inclusion criteria were as follows: advanced melanoma patients or sub-group analysis; assessed psychosocial outcomes; and English language. Fifty-two studies met review criteria (4 qualitative, 48 quantitative). Trials comprise mostly medical not psychosocial interventions, with psychosocial outcomes assessed within broader quality of life measures. Patients receiving chemotherapy or IFN-alpha showed decreased emotional and social function and increased distress. Five trials of newer therapies appeared to show improvements in emotional and social function. Descriptive studies suggest that patients with advanced, versus localized disease, had decreased emotional and social function and increased distress. Contributors to distress were largely unexplored, and no clear framework described coping/adjustment trajectories. Patients with advanced versus localized disease had more supportive care needs, particularly amount, quality, and timing of melanoma-related information, communication with and emotional support from clinicians. Limitations included: lack of theoretical underpinnings guiding study design; inconsistent measurement approaches; small sample sizes; non-representative sampling; and cross-sectional design. Quality trial evidence is needed to clarify the impact of treatment innovations for advanced melanoma on patients' psychosocial well-being. Survivorship research and subsequent translation of that knowledge into programs and services currently lags behind gains in the medical treatment of advanced melanoma, a troubling circumstance that requires immediate and focused attention. Copyright © 2016 John Wiley & Sons, Ltd.

Advances and prospects on biomolecules functionalized carbon nanotubes.

PubMed

Cui, Daxiang

2007-01-01

In recent years, functionalization of carbon nanotubes (CNTs) with biomolecules such as nucleotide acids, proteins, and polymers as well as cells have emerged as a new exciting field. Theoretical and experimental studies of structure and function of bio-inspired CNT composites have made great advances. The importance of nucleic acids, proteins, and polymers to the fundamental developments in CNT-based bio-nano-composites or devices has been recognized. In particular, biomechanics, biochemistry, thermodynamics, electronic, optical, and magnetic properties of the bio-inspired CNT composites have become a new interdisciplinary frontier in life science and nanomaterial science. Here we review some of the main advances in this field over the past few years, explore the application prospects, and discuss the issues, approaches, and challenges, with the aim of stimulating a broader interest in developing CNT-based bio-nanotechnology.

The advanced thermionic converter with microwave power as an auxiliary ionization source

NASA Technical Reports Server (NTRS)

Manikopoulos, C. N.; Hatziprocopiou, M.; Chiu, H. S.; Shaw, D. T.

1978-01-01

In the search for auxiliary sources of ionization for the advanced thermionic converter plasma, as required for terrestial applications, the use of externally applied microwave power is considered. The present work is part of the advanced model thermionic converter development research currently performed at the laboratory for Power and Environmental Studies at SUNY Buffalo. Microwave power in the frequency range 1-3 GHz is used to externally pump a thermionic converter and the results are compared to the theoretical model proposed by Lam (1976) in describing the thermionic converter plasma. The electron temperature of the plasma is found to be raised considerably by effective microwave heating which results in the disappearance of the double sheath ordinarily erected in front of the emitter. The experimental data agree satisfactorily with theory in the low current region.

An Analysis of the Tuition Advance Fund Bill.

ERIC Educational Resources Information Center

National Association of Independent Colleges and Universities, Washington, DC. National Inst. of Independent Colleges and Universities.

The Tuition Advance Fund (TAF) bill is analyzed on theoretical economic grounds, and forecasts of the net costs of the proposed program up to 1990 are offered. The TAF bill proposes the establishment of a new system of college loans as an addition to existing programs to allow students to borrow tuition plus an allowance for other costs. Novel…

A Cornerstone Course in Sociology: Providing Students with Theory, Methods, and Career Preparation Early in the Major

ERIC Educational Resources Information Center

Holtzman, Mellisa

2018-01-01

Cornerstone courses bridge introductory content from lower-level survey courses with the more advanced theoretical and methodological content of upper-level, major-only courses. Cornerstones are implemented with the goal of better preparing students for advanced coursework and/or assisting them with understanding their major and its associated…

Applications of surface analysis and surface theory in tribology

NASA Technical Reports Server (NTRS)

Ferrante, John

1988-01-01

Tribology, the study of adhesion, friction and wear of materials is a complex field which requires a knowledge of solid state physics, surface physics, chemistry, material science and mechanical engineering. It has been dominated, however, by the more practical need to make equipment work. With the advent of surface analysis and advances in surface and solid state theory, a new dimension has been added to the analysis of interactions at tribological interfaces. In this paper the applications of tribological studies and their limitations are presented. Examples from research at the NASA Lewis Research Center are given. Emphasis is on fundamental studies involving the effects of monolayer coverage and thick films on friction and wear. A summary of the current status of theoretical calculations of defect energetics is presented. In addition, some new theoretical techniques which enable simplified quantitative calculations of adhesion, fracture and friction are discussed.

Applications of surface analysis and surface theory in tribology

NASA Technical Reports Server (NTRS)

Ferrante, John

1989-01-01

Tribology, the study of adhesion, friction and wear of materials, is a complex field which requires a knowledge of solid state physics, surface physics, chemistry, material science, and mechanical engineering. It has been dominated, however, by the more practical need to make equipment work. With the advent of surface analysis and advances in surface and solid-state theory, a new dimension has been added to the analysis of interactions at tribological interfaces. In this paper the applications of tribological studies and their limitations are presented. Examples from research at the NASA Lewis Research Center are given. Emphasis is on fundamental studies involving the effects of monolayer coverage and thick films on friction and wear. A summary of the current status of theoretical calculations of defect energetics is presented. In addition, some new theoretical techniques which enable simplified quantitative calculations of adhesion, fracture, and friction are discussed.

The Self-Presentation Motives for Physical Activity Questionnaire: Instrument Development and Preliminary Construct Validity Evidence.

PubMed

Howle, Timothy C; Dimmock, James A; Whipp, Peter R; Jackson, Ben

2015-06-01

With the aim of advancing the literature on impression management in physical activity settings, we developed a theoretically derived 2 by 2 instrument that was designed to measure different types of context-specific self-presentation motives. Following item generation and expert review (Study 1), the instrument was completed by 206 group exercise class attendees (Study 2) and 463 high school physical education students (Study 3). Our analyses supported the intended factor structure (i.e., reflecting acquisitive-agentic, acquisitive-communal, protective-agentic, and protective-communal motives). We found some support for construct validity, and the self-presentation motives were associated with variables of theoretical and applied interest (e.g., impression motivation and construction, social anxiety, social and achievement goals, efficacy beliefs, engagement). Taken together, the results indicate that the Self-presentation Motives for Physical Activity Questionnaire (SMPAQ) may be useful for measuring various types of self-presentation motives in physical activity settings.

Self-efficacy in weight management.

PubMed

Clark, M M; Abrams, D B; Niaura, R S; Eaton, C A; Rossi, J S

1991-10-01

Self-efficacy is an important mediating mechanism in advancing understanding of the treatment of obesity. This study developed and validated the Weight Efficacy Life-Style Questionnaire (WEL), improving on previous studies by the use of clinical populations, cross-validation of the initial factor analysis, exploration of the best fitting theoretical model of self-efficacy, and examination of change in treatment. The resulting 20-item WEL consists of five situational factors: Negative Emotions, Availability, Social Pressure, Physical Discomfort, and Positive Activities. A hierarchical model was found to provide the best fit to the data. Results from two separate clinical treatment studies (total N = 382) show that the WEL is sensitive to changes in global scores as well as to a subset of the five situational factor scores. Treatment programs may be incomplete if they change only a subset of the situational dimensions of self-efficacy. Theoretical and clinical implications are discussed.

Theoretical and experimental research in aeroelastic stability of an advanced bearingless rotor for future helicopters

NASA Technical Reports Server (NTRS)

Wang, James M.

1991-01-01

The aeroelastic stability of a shaft-fixed bearingless rotor is analyzed in wind-tunnel tests for a wide range of operating conditions in order to determine whether such a system could be made aeroelastically stable without incorporating auxiliary dampers. The model rotor and blade properties are determined and used as an input to a bearingless-rotor analysis. Theoretical predictions are compared with experimental results in hover and forward flights. The analysis predicts the lag mode damping satisfactorily for collective pitch between 5 deg and 10 deg; however, the quasi-steady linear aerodynamic modeling overpredicts the damping values for higher collective pitch settings. It is noted that soft blade pitch links improve aeroelastic stability in hover and at low advance ratio.

Experimenting with theoretical motor neuroscience.

PubMed

Ajemian, Robert; Hogan, Neville

2010-11-01

Motor neuroscience is well over 100 years old, with seminal work such as G. T. Fritz and E. Hitzig's discovery of motor cortex occurring in 1870. Theoretical motor neuroscience has been ongoing for at least the last 50 years. How mature a scientific discipline is motor neuroscience? Are experimentalists and theoreticians working together productively to help the field progress? This article addresses these questions by advancing the following theses. Motor neuroscience remains at a descriptive stage due to the incredible complexity of the problem to be solved. The proliferation of models--and distinct modeling camps--stems from the absence of unifying conceptual constructs. To advance the field, theoreticians must rely more heavily on the concept of falsification by producing models that lend themselves to clear experimental testing.

A theoretical flaw in the advance market commitment idea.

PubMed

Sonderholm, Jorn

2010-06-01

Infectious and parasitic diseases cause massive health problems in the developing world. Research and development of drugs for diseases that mainly affect poor people in developing countries is limited. The advance market commitment (AMC) idea is an incentivising mechanism for research and development of drugs for neglected diseases. Discussion of the AMC idea is of renewed interest given the launch in June 2009 of the first AMC. This pilot AMC is designed to, among other things, test the idea for potential future applications. This paper is a critique of the AMC idea. It seeks to show that the idea has a hitherto unrecognised theoretical flaw that should make policy-makers and donors hesitant to embrace future applications of the idea.

The future challenge for aeropropulsion

NASA Technical Reports Server (NTRS)

Rosen, Robert; Bowditch, David N.

1992-01-01

NASA's research in aeropropulsion is focused on improving the efficiency, capability, and environmental compatibility for all classes of future aircraft. The development of innovative concepts, and theoretical, experimental, and computational tools provide the knowledge base for continued propulsion system advances. Key enabling technologies include advances in internal fluid mechanics, structures, light-weight high-strength composite materials, and advanced sensors and controls. Recent emphasis has been on the development of advanced computational tools in internal fluid mechanics, structural mechanics, reacting flows, and computational chemistry. For subsonic transport applications, very high bypass ratio turbofans with increased engine pressure ratio are being investigated to increase fuel efficiency and reduce airport noise levels. In a joint supersonic cruise propulsion program with industry, the critical environmental concerns of emissions and community noise are being addressed. NASA is also providing key technologies for the National Aerospaceplane, and is studying propulsion systems that provide the capability for aircraft to accelerate to and cruise in the Mach 4-6 speed range. The combination of fundamental, component, and focused technology development underway at NASA will make possible dramatic advances in aeropropulsion efficiency and environmental compatibility for future aeronautical vehicles.

Conference Proceedings on Guidance and Control Techniques for Advanced Space Vehicles (37th) Held at Florence, Italy on 27-30 September 1983.

DTIC Science & Technology

1984-01-01

P AD-A14l 969 CONFERENCE PROCEEDINGS ON GUIDANCE AND CONTROL 1 TECHNIQUES FOR ADVANCED SP-.(U,) ADVISORY GROUP FOR AEROSPACE RESEARCH AND DEVELOPMENT...findings of these various planning groups relativie to the ’e for advanced controls technology, and the perceived status of the technology t. me-,t... control of large flexible spacecraft. The program has also involved experimental activities to guide Ind validate the theoretical work. The

Focus on out-of-equilibrium dynamics in strongly interacting one-dimensional systems

NASA Astrophysics Data System (ADS)

Daley, A. J.; Rigol, M.; Weiss, D. S.

2014-09-01

In the past few years, there have been significant advances in understanding out-of-equilibrium dynamics in strongly interacting many-particle quantum systems. This is the case for 1D dynamics, where experimental advances—both with ultracold atomic gases and with solid state systems—have been accompanied by advances in theoretical methods, both analytical and numerical. This ‘focus on’ collection brings together 17 new papers, which together give a representative overview of the recent advances.

Highlights of theoretical progress related to the International Magnetospheric Study

NASA Technical Reports Server (NTRS)

Hill, T. W.

1982-01-01

U.S. theoretical research efforts have addressed three areas within the International Magnetospheric Study. The first, solar wind/magnetosphere interaction, is presently concerned with the suggestion that magnetic merging may predominantly occur near the polar cusps rather than near the subsolar point. Mechanisms have been proposed for noncollisional diffusion of solar wind plasma across the closed magnetopause entailed by such a phenomenon. The second area considers the importance to magnetotail dynamics of a continuous source of solar wind plasma, and of sporadic plasma loss associated with an unsteady convection cycle. In the third area, the electrodynamic magnetosphere/ionosphere interaction, an advanced state has been reached in the understanding of the relevant physics, with respect both to coupling in the subauroral region and the large scale structure of auroral zone electric fields parallel, and perpendicular to, the magnetic field.

Attachment-related mental representations: introduction to the special issue.

PubMed

Thompson, Ross A

2008-12-01

Bowlby's concept of mental working models of self, attachment figures, and the social world has been theoretically generative as a bridge between early relational experience and the beliefs and expectations that color later relationships. Contemporary attachment researchers, following his example, are applying new knowledge of children's conceptual development to their study of attachment-related mental representations in children and adults. The contributors to this special issue highlight recent advances in how the mental representations arising from attachment security should be conceptualized and studied, and identify a number of important directions for future work. This paper introduces the special issue by summarizing the major ideas of Bowlby and his followers concerning the nature and development of mental working models, points of theoretical clarity and uncertainty, and challenges in assessing these representations, as well as profiling each of the contributions to this issue.

Theoretical and Computational Investigation of High-Brightness Beams

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

Chen, Chiping

Theoretical and computational investigations of adiabatic thermal beams have been carried out in parameter regimes relevant to the development of advanced high-brightness, high-power accelerators for high-energy physics research and for various applications such as light sources. Most accelerator applications require high-brightness beams. This is true for high-energy accelerators such as linear colliders. It is also true for energy recovery linacs (ERLs) and free electron lasers (FELs) such as x-ray free electron lasers (XFELs). The breakthroughs and highlights in our research in the period from February 1, 2013 to November 30, 2013 were: a) Completion of a preliminary theoretical and computationalmore » study of adiabatic thermal Child-Langmuir flow (Mok, 2013); and b) Presentation of an invited paper entitled ?Adiabatic Thermal Beams in a Periodic Focusing Field? at Space Charge 2013 Workshop, CERN, April 16-19, 2013 (Chen, 2013). In this report, an introductory background for the research project is provided. Basic theory of adiabatic thermal Child-Langmuir flow is reviewed. Results of simulation studies of adiabatic thermal Child-Langmuir flows are discussed.« less

Magnitude, moment, and measurement: The seismic mechanism controversy and its resolution.

PubMed

Miyake, Teru

This paper examines the history of two related problems concerning earthquakes, and the way in which a theoretical advance was involved in their resolution. The first problem is the development of a physical, as opposed to empirical, scale for measuring the size of earthquakes. The second problem is that of understanding what happens at the source of an earthquake. There was a controversy about what the proper model for the seismic source mechanism is, which was finally resolved through advances in the theory of elastic dislocations. These two problems are linked, because the development of a physically-based magnitude scale requires an understanding of what goes on at the seismic source. I will show how the theoretical advances allowed seismologists to re-frame the questions they were trying to answer, so that the data they gathered could be brought to bear on the problem of seismic sources in new ways. Copyright © 2017 Elsevier Ltd. All rights reserved.

Optical Spectroscopy of Hybrid Semiconductor Quantum Dots and Metal Nanoparticles

DTIC Science & Technology

2014-11-07

Theoretical studies of spin- photon entangled complementarity”. Mr. Anderson Hayes in physics finished B.S. degree in May 2013 with a capstone thesis entitled...working on “Semiconductor quantum dots and photon entanglement ”. Mr. Quinn Allen Hailes, undergraduate student in physics completed B.S. degree in...great interests for the Department of Defense’s (DoD) photonic applications. Our research focused on developing and characterizing advanced optical

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

Degrand, Thomas

The Theoretical Advanced Study Institute was held at the University of Colorado, Boulder, during June 1 - 26, 2015. The topic was "New Frontiers in Fields and Strings." Topics included many discussions of entanglement entropy, the conformal bootstrap, AdS/CFT techniques and applications, cosmology, and the black hole information problem. The organizers were Professors Joseph Polchinski (KITP Santa Barbara) and Pedro Vieira (Perimeter Institute). Sixty-one students heard sixty-two lectures by sixteen lecturers. A Proceedings is in press.

The study of X-ray scattering to determine surface topography of smooth surfaces. [X-ray telescope mirrors

NASA Technical Reports Server (NTRS)

Williams, A. C.

1982-01-01

The scattering of X-rays from state-of-the-art polished mirrors is discussed with reference to the requirements of the Advanced X-ray Astrophysics Facility telescope. An experimental set-up is described which allows information to be obtained with subarcsecond resolution. A sample of the data obtained is presented along with a possible theoretical model for its interpretation.

Temporal and spatial context in the mind and brain.

PubMed

Howard, Marc W

2017-10-01

Theories of episodic memory have long hypothesized that recollection of a specific instance from one's life is mediated by recovery of a neural state of spatiotemporal context. This paper reviews recent theoretical advances in formal models of spatiotemporal context and a growing body of neurophysiological evidence from human imaging studies and animal work that neural populations in the hippocampus and other brain regions support a representation of spatiotemporal context.

Experimental, Theoretical and Computational Studies of Plasma-Based Concepts for Future High Energy Accelerators

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

Joshi, Chan; Mori, W.

2013-10-21

This is the final report on the DOE grant number DE-FG02-92ER40727 titled, “Experimental, Theoretical and Computational Studies of Plasma-Based Concepts for Future High Energy Accelerators.” During this grant period the UCLA program on Advanced Plasma Based Accelerators, headed by Professor C. Joshi has made many key scientific advances and trained a generation of students, many of whom have stayed in this research field and even started research programs of their own. In this final report however, we will focus on the last three years of the grant and report on the scientific progress made in each of the four tasksmore » listed under this grant. Four tasks are focused on: Plasma Wakefield Accelerator Research at FACET, SLAC National Accelerator Laboratory, In House Research at UCLA’s Neptune and 20 TW Laser Laboratories, Laser-Wakefield Acceleration (LWFA) in Self Guided Regime: Experiments at the Callisto Laser at LLNL, and Theory and Simulations. Major scientific results have been obtained in each of the four tasks described in this report. These have led to publications in the prestigious scientific journals, graduation and continued training of high quality Ph.D. level students and have kept the U.S. at the forefront of plasma-based accelerators research field.« less

[Memorandum IV: Theoretical and Normative Grounding of Health Services Research].

PubMed

Baumann, W; Farin, E; Menzel-Begemann, A; Meyer, T

2016-05-01

With Memoranda and other initiatives, the German Network for Health Service Research [Deutsches Netzwerk Versorgungsforschung e.V. (DNVF)] is fostering the methodological quality of care research studies for years. Compared to the standards of empirical research, questions concerning the role and function of theories, theoretical approaches and scientific principles have not been taken up on its own. Therefore, the DNVF e.V. has set up a working group in 2013, which was commissioned to prepare a memorandum on "theories in health care research". This now presented memorandum will primarily challenge scholars in health care services research to pay more attention to questions concerning the theoretical arsenal and the background assumptions in the research process. The foundation in the philosophy of science, the reference to normative principles and the theory-bases of the research process are addressed. Moreover, the memorandum will call on to advance the theorizing in health services research and to strengthen not empirical approaches, research on basic principles or studies with regard to normative sciences and to incorporate these relevant disciplines in health services research. Research structures and funding of health services research needs more open space for theoretical reflection and for self-observation of their own, multidisciplinary research processes. © Georg Thieme Verlag KG Stuttgart · New York.

Recent Advances in Understanding Particle Acceleration Processes in Solar Flares

NASA Astrophysics Data System (ADS)

Zharkova, V. V.; Arzner, K.; Benz, A. O.; Browning, P.; Dauphin, C.; Emslie, A. G.; Fletcher, L.; Kontar, E. P.; Mann, G.; Onofri, M.; Petrosian, V.; Turkmani, R.; Vilmer, N.; Vlahos, L.

2011-09-01

We review basic theoretical concepts in particle acceleration, with particular emphasis on processes likely to occur in regions of magnetic reconnection. Several new developments are discussed, including detailed studies of reconnection in three-dimensional magnetic field configurations (e.g., current sheets, collapsing traps, separatrix regions) and stochastic acceleration in a turbulent environment. Fluid, test-particle, and particle-in-cell approaches are used and results compared. While these studies show considerable promise in accounting for the various observational manifestations of solar flares, they are limited by a number of factors, mostly relating to available computational power. Not the least of these issues is the need to explicitly incorporate the electrodynamic feedback of the accelerated particles themselves on the environment in which they are accelerated. A brief prognosis for future advancement is offered.

Numerical assessment of residual formability in sheet metal products: towards design for sustainability

NASA Astrophysics Data System (ADS)

Falsafi, Javad; Demirci, Emrah; Silberschmidt, Vadim. V.

2016-08-01

A new computational scheme is presented to addresses cold recyclability of sheet- metal products. Cold recycling or re-manufacturing is an emerging area studied mostly empirically; in its current form, it lacks theoretical foundation especially in the area of sheet metals. In this study, a re-formability index was introduced based on post-manufacture residual formability in sheet metal products. This index accounts for possible levels of deformation along different strain paths based on Polar Effective Plastic Strain (PEPS) technique. PEPS is strain-path independent, hence provides a foundation for residual formability analysis. A user- friendly code was developed to implement this assessment in conjunction with advanced finite- element (FE) analysis. The significance of this approach is the advancement towards recycling of sheet metal products without melting them.

Qualitative and Quantitative Distinctions in Personality Disorder

PubMed Central

Wright, Aidan G. C.

2011-01-01

The “categorical-dimensional debate” has catalyzed a wealth of empirical advances in the study of personality pathology. However, this debate is merely one articulation of a broader conceptual question regarding whether to define and describe psychopathology as a quantitatively extreme expression of normal functioning or as qualitatively distinct in its process. In this paper I argue that dynamic models of personality (e.g., object-relations, cognitive-affective processing system) offer the conceptual scaffolding to reconcile these seemingly incompatible approaches to characterizing the relationship between normal and pathological personality. I propose that advances in personality assessment that sample behavior and experiences intensively provide the empirical techniques, whereas interpersonal theory offers an integrative theoretical framework, for accomplishing this goal. PMID:22804676

UTSG-2; A theoretical model describing the transient behavior of a pressurized water reactor natural circulation U-tube steam generator

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

Hold, A.

An advanced nonlinear transient model for calculating steady-state and dynamic behaviors of characteristic parameters of a Kraftwerk Union-type vertical natural-circulation U-tube steam generator and its main steam system is presented. This model has been expanded due to the increasing need for safety-related accident research studies. It now takes into consideration the possibilities of dryout and superheating along the secondary side of the steam generator. The resulting theoretical model is the basis of the digital code UTSG-2, which can be used both by itself and in combination with other pressurized water reactor transient codes, such as ALMOD-3.4, AMOD-4, and ATHLET.

Curvilinear electronics formed using silicon membrane circuits and elastomeric transfer elements.

PubMed

Ko, Heung Cho; Shin, Gunchul; Wang, Shuodao; Stoykovich, Mark P; Lee, Jeong Won; Kim, Dong-Hun; Ha, Jeong Sook; Huang, Yonggang; Hwang, Keh-Chih; Rogers, John A

2009-12-01

Materials and methods to achieve electronics intimately integrated on the surfaces of substrates with complex, curvilinear shapes are described. The approach exploits silicon membranes in circuit mesh structures that can be deformed in controlled ways using thin, elastomeric films. Experimental and theoretical studies of the micromechanics of such curvilinear electronics demonstrate the underlying concepts. Electrical measurements illustrate the high yields that can be obtained. The results represent significant experimental and theoretical advances over recently reported concepts for creating hemispherical photodetectors in electronic eye cameras and for using printable silicon nanoribbons/membranes in flexible electronics. The results might provide practical routes to the integration of high performance electronics with biological tissues and other systems of interest for new applications.

PATIKAweb: a Web interface for analyzing biological pathways through advanced querying and visualization.

PubMed

Dogrusoz, U; Erson, E Z; Giral, E; Demir, E; Babur, O; Cetintas, A; Colak, R

2006-02-01

Patikaweb provides a Web interface for retrieving and analyzing biological pathways in the Patika database, which contains data integrated from various prominent public pathway databases. It features a user-friendly interface, dynamic visualization and automated layout, advanced graph-theoretic queries for extracting biologically important phenomena, local persistence capability and exporting facilities to various pathway exchange formats.

Prospects for Significant Theoretical Advances in Communication: The Role of the Interesting Question.

ERIC Educational Resources Information Center

Gouran, Dennis S.

This paper discusses ways in which the field of speech communication can be advanced. The first half of the paper characterizes the objectivist and subjectivist views of how knowledge is acquired and the forms of inquiry to which these views have led. The remainder of the paper demonstrates the role that the "interesting question" (one for which…

Documenting Student Engagement Using an Intention/Reflection Exercise during an Advanced Pharmacy Practice Experience

ERIC Educational Resources Information Center

Fierke, Kerry K.; Lepp, Gardner A.

2015-01-01

The article shares the outcomes of a practice called Intention/Reflection (I/R) when applied to a group of ten students in a five-week course involving an international advanced pharmacy practice experience. Developed by the authors and founded on a combination of theoretical principles, this practice is unique because of the blend of formative…

Advanced Avionic Systems for Multimission Applications. Volume I.

DTIC Science & Technology

1982-10-01

technical report are theoretical and in no way reflect Air Fortp-nwnpid qnftwRrp png ramc 19. KEY WORDS (Continue on reveree aide It neceeary and Identify...addressed (1) the Development & Evaluation of Advanced Digital Avionics System Architectures and (2) the Development of a Single Processor Synchronous...29 4.3.2 Memory Technologies . . . . . . . . . . . . . . . . . 30 4.3.3 BIU Technology . . . . . . . . . . . . . . . . . . . 33

OSA Imaging and Applied Optics Congress Support

DTIC Science & Technology

2017-02-16

ranged from theoretical to experimental demonstration and verification of the latest advances in computational imaging research . This meeting covered...Approved OMB No. 0704-0188 The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time ...Applied Optics Congress was a four-day meeting that encompassed the latest advances in computational imaging research . emphasizing integration of

Contending with advanced illness: patient and caregiver perspectives.

PubMed

Meeker, Mary Ann; Waldrop, Deborah P; Schneider, Jaclyn; Case, Amy A

2014-05-01

Despite improvements in end-of-life care, some unrelieved suffering persists for patients with advanced illness and their family members. Hospice and palliative care services can reduce suffering, but these services remain under-used. To investigate how patients with advanced illness and their primary caregivers experienced and responded to health care needs and decision making and how some dyads moved toward comfort-focused care. This was a qualitative study using the grounded theory method for sample selection, data collection, and analysis. Dyadic semi-structured interviews were audio-recorded and transcribed for analysis. Twenty-two participants, 12 patients and 10 family surrogates, provided 16 interviews for this study. Participants engaged in a process of contending with advanced illness. The major phases comprising this process were suffering, struggling, and settling. Struggling included enduring the experience and fighting the illness. During the phase of settling, the focus shifted away from curative efforts and toward supportive care. Conditions that facilitated the movement into this phase included receiving clear and consistent information about the patient's health status, trusting health care providers, having attended to advance care planning in some form, and being aware of and able to acknowledge the terminal nature of the illness. Findings from this pilot study offer a preliminary theoretical model to enhance the understanding of patient and family caregiver needs during advanced illness. Awareness of their perspective can inform the timing and content of clinicians' communication and interventions. Copyright © 2014 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved.

Consciousness Regained: Disentangling Mechanisms, Brain Systems, and Behavioral Responses.

PubMed

Storm, Johan F; Boly, Mélanie; Casali, Adenauer G; Massimini, Marcello; Olcese, Umberto; Pennartz, Cyriel M A; Wilke, Melanie

2017-11-08

How consciousness (experience) arises from and relates to material brain processes (the "mind-body problem") has been pondered by thinkers for centuries, and is regarded as among the deepest unsolved problems in science, with wide-ranging theoretical, clinical, and ethical implications. Until the last few decades, this was largely seen as a philosophical topic, but not widely accepted in mainstream neuroscience. Since the 1980s, however, novel methods and theoretical advances have yielded remarkable results, opening up the field for scientific and clinical progress. Since a seminal paper by Crick and Koch (1998) claimed that a science of consciousness should first search for its neural correlates (NCC), a variety of correlates have been suggested, including both content-specific NCCs, determining particular phenomenal components within an experience, and the full NCC, the neural substrates supporting entire conscious experiences. In this review, we present recent progress on theoretical, experimental, and clinical issues. Specifically, we (1) review methodological advances that are important for dissociating conscious experience from related enabling and executive functions, (2) suggest how critically reconsidering the role of the frontal cortex may further delineate NCCs, (3) advocate the need for general, objective, brain-based measures of the capacity for consciousness that are independent of sensory processing and executive functions, and (4) show how animal studies can reveal population and network phenomena of relevance for understanding mechanisms of consciousness. Copyright © 2017 the authors 0270-6474/17/3710882-12$15.00/0.

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

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

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

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

Developing a theoretical framework for complex community-based interventions.

PubMed

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

2014-01-01

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

Planetary Sciences: American and Soviet Research

NASA Technical Reports Server (NTRS)

Donahue, Thomas M. (Editor); Trivers, Kathleen Kearney (Editor); Abramson, David M. (Editor)

1991-01-01

Papers presented at the US-USSR Workshop on Planetary Sciences are compiled. The purpose of the workshop was to examine the current state of theoretical understanding of how the planets were formed and how they evolved to their present state. The workshop assessed the types of observations and experiments that are needed to advance understanding of the formation and evolution of the solar system based on the current theoretical framework.

Theoretical Studies of Elementary Hydrocarbon Species and Their Reactions

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

Allen, Wesley D.; Schaefer, Henry F.

The research program supported by this DOE grant carried out both methodological development and computational applications of first-principles theoretical chemistry based on quantum mechanical wavefunctions, as directed toward understanding and harnessing the fundamental chemical physics of combustion. To build and refine the world’s database of thermochemistry, spectroscopy, and chemical kinetics, predictive and definitive computational methods are needed that push the envelope of modern electronic structure theory. The application of such methods has been made to gain comprehensive knowledge of the paradigmatic reaction networks by which the n- and i-propyl, t-butyl, and n-butyl radicals are oxidized by O 2. Numerous ROOmore » and QOOH intermediates in these R + O 2 reaction systems have been characterized along with the interconnecting isomerization transition states and the barriers leading to fragmentation. Other combustion-related intermediates have also been studied, including methylsulfinyl radical, cyclobutylidene, and radicals derived from acetaldehyde and vinyl alcohol. Theoretical advances have been achieved and made available to the scientific community by implementation into PSI4, an open-source electronic structure computer package emphasizing automation, advanced libraries, and interoperability. We have pursued the development of universal explicitly correlated methods applicable to general electronic wavefunctions, as well as a framework that allows multideterminant reference functions to be expressed as a single determinant from quasiparticle operators. Finally, a rigorous analytical tool for correlated wavefunctions has been created to elucidate dispersion interactions, which play essential roles in many areas of chemistry, but whose effects are often masked and enigmatic. Our research decomposes and analyzes the coupled-cluster electron correlation energy in molecular systems as a function of interelectronic distance. Concepts are emerging that can be used to explain the influence of dispersion on the thermochemistry of large hydrocarbons, including fuels important to combustion technologies.« less

Case study and case-based research in emergency nursing and care: Theoretical foundations and practical application in paramedic pre-hospital clinical judgment and decision-making of patients with mental illness.

PubMed

Shaban, Ramon Z; Considine, Julie; Fry, Margaret; Curtis, Kate

2017-02-01

Generating knowledge through quality research is fundamental to the advancement of professional practice in emergency nursing and care. There are multiple paradigms, designs and methods available to researchers to respond to challenges in clinical practice. Systematic reviews, randomised control trials and other forms of experimental research are deemed the gold standard of evidence, but there are comparatively few such trials in emergency care. In some instances it is not possible or appropriate to undertake experimental research. When exploring new or emerging problems where there is limited evidence available, non-experimental methods are required and appropriate. This paper provides the theoretical foundations and an exemplar of the use of case study and case-based research to explore a new and emerging problem in the context of emergency care. It examines pre-hospital clinical judgement and decision-making of mental illness by paramedics. Using an exemplar the paper explores the theoretical foundations and conceptual frameworks of case study, it explains how cases are defined and the role researcher in this form of inquiry, it details important principles and the procedures for data gathering and analysis, and it demonstrates techniques to enhance trustworthiness and credibility of the research. Moreover, it provides theoretically and practical insights into using case study in emergency care. Copyright © 2017 College of Emergency Nursing Australasia. Published by Elsevier Ltd. All rights reserved.

Theory and applications of structured light single pixel imaging

NASA Astrophysics Data System (ADS)

Stokoe, Robert J.; Stockton, Patrick A.; Pezeshki, Ali; Bartels, Randy A.

2018-02-01

Many single-pixel imaging techniques have been developed in recent years. Though the methods of image acquisition vary considerably, the methods share unifying features that make general analysis possible. Furthermore, the methods developed thus far are based on intuitive processes that enable simple and physically-motivated reconstruction algorithms, however, this approach may not leverage the full potential of single-pixel imaging. We present a general theoretical framework of single-pixel imaging based on frame theory, which enables general, mathematically rigorous analysis. We apply our theoretical framework to existing single-pixel imaging techniques, as well as provide a foundation for developing more-advanced methods of image acquisition and reconstruction. The proposed frame theoretic framework for single-pixel imaging results in improved noise robustness, decrease in acquisition time, and can take advantage of special properties of the specimen under study. By building on this framework, new methods of imaging with a single element detector can be developed to realize the full potential associated with single-pixel imaging.

On the hunt for elusive ``meanings''

NASA Astrophysics Data System (ADS)

Roth, Wolff-Michael

2012-09-01

The feature article discussed in this forum presents an interesting description of how students work in the context of a virtual world, where they design phenomena that they subsequently investigate by analyzing graphical representations. The study is aligned with the current canon of science education interested in understanding the inter-psychological and intra-psychological determinants of learning. Its main focus is on "meaning making." In this contribution to the forum, I articulate some shortcomings inherent in this theoretical notion, which, in essence, hides rather than reveals the real issues in and of learning. I offer some alternative avenues, both theoretical and methodological, for framing pertinent issues; in so doing, I (endeavor to) open up new avenues for research in science education. In essence, therefore, I offer possible avenues in response to the question, "What more can there be done by science education research?" that would allow us to eschew what I perceive to be hidden contradictions that interfere with making theoretical and practical advances in our field.

Siblings of Youth with Autism Spectrum Disorders: Theoretical Perspectives on Sibling Relationships and Individual Adjustment.

PubMed

McHale, Susan M; Updegraff, Kimberly A; Feinberg, Mark E

2016-02-01

A burgeoning research literature investigates the sibling relationships of youth with autism spectrum disorder (ASD) and their implications for individual adjustment. Focusing on four relationship domains—behaviors,emotions, cognitions and involvement—and toward advancing this generally a theoretical literature, were view and apply tenets from a range of theoretical perspectives in an effort to illuminate the mechanisms underlying sibling relationship experiences and their adjustment implications. Our review suggests new directions for research to test theoretically-grounded hypotheses about how sibling relationships develop and are linked to individual adjustment. In addition, we consider how identifying underlying bio-psycho-social processes can aid in the development of interventions to promote warm and involved sibling relationships and positive youth development.

Cultural Neuroscience: Progress and Promise

PubMed Central

Chiao, Joan Y.; Cheon, Bobby K.; Pornpattanangkul, Narun; Mrazek, Alissa J.; Blizinsky, Katherine D.

2013-01-01

The nature and origin of human diversity has been a source of intellectual curiosity since the beginning of human history. Contemporary advances in cultural and biological sciences provide unique opportunities for the emerging field of cultural neuroscience. Research in cultural neuroscience examines how cultural and genetic diversity shape the human mind, brain and behavior across multiple time scales: situation, ontogeny and phylogeny. Recent progress in cultural neuroscience provides novel theoretical frameworks for understanding the complex interaction of environmental, cultural and genetic factors in the production of adaptive human behavior. Here, we provide a brief history of cultural neuroscience, theoretical and methodological advances, as well as empirical evidence of the promise of and progress in the field. Implications of this research for population health disparities and public policy are discussed. PMID:23914126

Simple, but not easy - Opportunities and challenges from teachers' and students' perspectives in the 21st century of veterinary parasitology teaching.

PubMed

Strube, Christina; Raue, Katharina; Janecek, Elisabeth

2018-03-15

One of the main goals in academia is, and has been, high quality education of students to provide theoretical and practical knowledge essential for professional life. Achieving this goal is highly dependent on teaching procedures and, consequently, on a constant adaptation of teaching styles to align to technical advances and cutting-edge topics. Technical advances can strongly influence teaching and learning in the complex subject area of veterinary parasitology. Today's students are provided with extensive, digital lecture notes, and e-learning offers including virtual microscope technology to independently obtain intensified theoretical knowledge and understanding. As veterinary parasitology is also highly reliant on proficient practical skills, lectures with integrated diagnostic exercises are mandatory. Nowadays, such practical skills, such as carrying out faecal examination procedures, can be strengthened by having access to clinical skills labs. Advances such as digital lecture notes, e-learning and virtual microscopes do not only provide new, innovative opportunities, but can also comprise challenges. In this context, provision of sufficient relevant studying material may discourage students to take on responsibilities for autonomous gathering of information. Besides technical advances, 'Zeitgeist' changes are shaping teaching contents, which are progressively expanding as zoonoses are increasingly being focused on. With the aim of adopting the one-health concept, students today are expected not only to bear responsibilities for animals, but also for their owners and public health. This article will cast light on some key challenges and opportunities in modern veterinary parasitology teaching from the teachers´ and the students´ perspectives. Copyright © 2018 Elsevier B.V. All rights reserved.

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

PubMed

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

2017-04-08

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

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.

Blunt chest trauma.

PubMed

Stewart, Daphne J

2014-01-01

Blunt chest trauma is associated with a wide range of injuries, many of which are life threatening. This article is a case study demonstrating a variety of traumatic chest injuries, including pathophysiology, diagnosis, and treatment. Literature on the diagnosis and treatment was reviewed, including both theoretical and research literature, from a variety of disciplines. The role of the advance practice nurse in trauma is also discussed as it relates to assessment, diagnosis, and treatment of patients with traumatic chest injuries.

Facts and fiction of learning systems. [decision making intelligent control

NASA Technical Reports Server (NTRS)

Saridis, G. N.

1975-01-01

The methodology that will provide the updated precision for the hardware control and the advanced decision making and planning in the software control is called learning systems and intelligent control. It was developed theoretically as an alternative for the nonsystematic heuristic approaches of artificial intelligence experiments and the inflexible formulation of modern optimal control methods. Its basic concepts are discussed and some feasibility studies of some practical applications are presented.

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

NASA Astrophysics Data System (ADS)

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

2014-02-01

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

Lithium Iron Orthosilicate Cathode: Progress and Perspectives

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

Ni, Jiangfeng; Jiang, Yu; Bi, Xuanxuan

2017-07-18

The pursuit of cathodes with a high capacity is remarkably driven by the ever increasing demand of high-energy lithium ion batteries in electronics and transportation. In this regard, polyanionic lithium iron orthosilicate (Li2FeSiO4) offers a promising opportunity because it affords a high theoretical capacity of 331 mAh g–1. However, such a high theoretical capacity of Li2FeSiO4 has frequently been compromised in practice because of the extremely low electronic and ionic conductivity. To address this issue, material engineering strategies to boost the Li storage kinetics in Li2FeSiO4 have proven indispensable. In this Perspective, we will briefly present the structural characteristics, intrinsicmore » physicochemical properties, and electrochemical behavior of Li2FeSiO4. We particularly focus on recent materials engineering of silicates, which is implemented mainly through advanced synthetic techniques and elaborate controls. This Perspective highlights the importance of integrating theoretical analysis into experimental implementation to further advance the Li2FeSiO4 materials.« less

Kinematic Optimization in Birds, Bats and Ornithopters

NASA Astrophysics Data System (ADS)

Reichert, Todd

Birds and bats employ a variety of advanced wing motions in the efficient production of thrust. The purpose of this thesis is to quantify the benefit of these advanced wing motions, determine the optimal theoretical wing kinematics for a given flight condition, and to develop a methodology for applying the results in the optimal design of flapping-wing aircraft (ornithopters). To this end, a medium-fidelity, combined aero-structural model has been developed that is capable of simulating the advanced kinematics seen in bird flight, as well as the highly non-linear structural deformations typical of high-aspect ratio wings. Five unique methods of thrust production observed in natural species have been isolated, quantified and thoroughly investigated for their dependence on Reynolds number, airfoil selection, frequency, amplitude and relative phasing. A gradient-based optimization algorithm has been employed to determined the wing kinematics that result in the minimum required power for a generalized aircraft or species in any given flight condition. In addition to the theoretical work, with the help of an extended team, the methodology was applied to the design and construction of the world's first successful human-powered ornithopter. The Snowbird Human-Powered Ornithopter, is used as an example aircraft to show how additional design constraints can pose limits on the optimal kinematics. The results show significant trends that give insight into the kinematic operation of natural species. The general result is that additional complexity, whether it be larger twisting deformations or advanced wing-folding mechanisms, allows for the possibility of more efficient flight. At its theoretical optimum, the efficiency of flapping-wings exceeds that of current rotors and propellers, although these efficiencies are quite difficult to achieve in practice.

Development of advanced capitalism: a case study of retired coal miners in southern West Virginia

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

Legeay, S.P.

1980-01-01

This dissertation develops a critical analysis of changes in American society during the last fifty years. It is focused in particular on the southern West Virginia coal fields, and examines the changes in class structure (specifically, coal miners), the labor process, the union, class consciousness, community and leisure. The study is grounded within a theoretical perspective that is dialectical. It is concerned with the interaction between specific social categories (such as the union) and the greater whole of capitalist development. It is centrally concerned with continuing a research orientation to which the Frankfurt School gave a powerful contribution: the developmentmore » of advanced capitalism in the modern epoch. The study utilizes life-history interviews with retired coal miners, almost all of whom had experience with the exploitive company towns of an earlier time. Thus, techniques for the study of oral history are instrumental in developing an analysis of social developments, inasmuch as they provide data appropriate for an analysis of the transformation from early to late capitalism. Finally, this dissertation examines a problem central to dialectical theory, that of the relation between theory and praxis, by approaching the life histories as exemplifications of collective (i.e., social) experience. It integrates the biographical experience of individual miners with the theoretical dimensions of political economy in early and late capitalism. The current crisis in the coal fields is examined, with a view to possible transformation.« less

Software reliability through fault-avoidance and fault-tolerance

NASA Technical Reports Server (NTRS)

Vouk, Mladen A.; Mcallister, David F.

1993-01-01

Strategies and tools for the testing, risk assessment and risk control of dependable software-based systems were developed. Part of this project consists of studies to enable the transfer of technology to industry, for example the risk management techniques for safety-concious systems. Theoretical investigations of Boolean and Relational Operator (BRO) testing strategy were conducted for condition-based testing. The Basic Graph Generation and Analysis tool (BGG) was extended to fully incorporate several variants of the BRO metric. Single- and multi-phase risk, coverage and time-based models are being developed to provide additional theoretical and empirical basis for estimation of the reliability and availability of large, highly dependable software. A model for software process and risk management was developed. The use of cause-effect graphing for software specification and validation was investigated. Lastly, advanced software fault-tolerance models were studied to provide alternatives and improvements in situations where simple software fault-tolerance strategies break down.

New Results on Short-Range Correlations in Nuclei

DOE PAGES

Fomin, Nadia; Higinbotham, Douglas; Sargsian, Misak; ...

2017-10-12

Nuclear dynamics at short distances is one of the most fascinating topics of strong interaction physics. The physics of it is closely related to the understanding of the role of the QCD in generating nuclear forces at short distances, as well as of the dynamics of the superdense cold nuclear matter relevant to the interior of neutron stars. The emergence of high-energy electron and proton beams has led to significant recent progress in high-energy nuclear scattering experiments investigating the short-range structure of nuclei. These experiments, in turn, have stimulated new theoretical studies resulting in the observation of several new phenomenamore » specific to the short-range structure of nuclei. In this article, we review recent theoretical and experimental progress in studies of short-range correlations in nuclei and discuss their importance for advancing our understanding of the dynamics of nuclear interactions at short distances.« less

Theoretical Studies of Dust in the Galactic Environment: Some Recent Advances

NASA Technical Reports Server (NTRS)

Leung, Chun Ming

1995-01-01

Dust grains, although a minor constituent, play a very important role in the thermodynamics and evolution of many astronomical objects, e.g., young and evolved stars, nebulae, interstellar clouds, and nuclei of some galaxies. Since the birth of infrared astronomy over two decades ago, significant progress has been made not only in the observations of galactic dust, but also in the theoretical studies of phenomena involving dust grains. Models with increasing degree of sophistication and physical realism (in terms of grain properties, dust formation, emission processes, and grain alignment mechanisms) have become available. Here I review recent progress made in the following areas: (1) Extinction and emission of fractal grains. (2) Dust formation in radiation-driven outflows of evolved stars. (3) Transient heating and emission of very small dust grains. Where appropriate, relevant modeling results are presented and observational implications emphasized.

New Results on Short-Range Correlations in Nuclei

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

Fomin, Nadia; Higinbotham, Douglas; Sargsian, Misak

Nuclear dynamics at short distances is one of the most fascinating topics of strong interaction physics. The physics of it is closely related to the understanding of the role of the QCD in generating nuclear forces at short distances, as well as of the dynamics of the superdense cold nuclear matter relevant to the interior of neutron stars. The emergence of high-energy electron and proton beams has led to significant recent progress in high-energy nuclear scattering experiments investigating the short-range structure of nuclei. These experiments, in turn, have stimulated new theoretical studies resulting in the observation of several new phenomenamore » specific to the short-range structure of nuclei. In this article, we review recent theoretical and experimental progress in studies of short-range correlations in nuclei and discuss their importance for advancing our understanding of the dynamics of nuclear interactions at short distances.« less

Ferromagnetic ordering and halfmetallic state in a shandite: Co3Sn2S2

NASA Astrophysics Data System (ADS)

Schnelle, Walter; Leithe-Jasper, Andreas; Rosner, Helge; Weihrich, Richard

2013-03-01

The rapid advance in spintronics challenges an improved understanding of the underlying microscopic properties. Here, we present a joint experimental and theoretical study of Co3Sn2S2 (shandite) and related compounds. From magnetic susceptibility, specific heat and magneto-transport measurements on a shandite single crystal sample we find a phase transition to a ferromagnetic metallic state at 177 K with a saturation moment of 0.92 μB/f.u. Full potential electronic structure calculations within the local spin density approximation result in a halfmetallic ferromagnetic groundstate with a moment of 1 μB/f.u. and a tiny gap in the minority spin channel. The calculated structure optimization and structure variations show that the size of the gap is rather sensitive to the lattice geometry. Possiblities to stabilize the halfmetallic ferromagnetic behavior by various substitutions have been studied theoretically and will be discussed.

Involved, United, and Efficacious: Could Self-Affirmation Be the Solution to California's Drought?

PubMed

Walter, Nathan; Demetriades, Stefanie Z; Murphy, Sheila T

2017-09-01

Self-affirmation theory posits that thoughts and actions that affirm an important aspect of the self-concept can make people more susceptible to change by casting their self in a positive light. Whereas much of the current literature has been restricted to individual-level concerns, the current study provides longitudinal evidence for behavioral outcomes in the context of the California drought, advancing our theoretical knowledge regarding the underlying processes that lead self-affirmed individuals to address societal risks and collective concerns. The results of a three-wave experimental study (N = 91) indicated that relative to nonaffirmed counterparts, self-affirmed participants reported on higher levels of support for water conservation policies, as well as on reduction of water use that endured for 30 days following the self-affirming manipulation. In both cases, the effects were mediated by collective-efficacy but not by self-efficacy. Relevant explanations are considered and practical and theoretical implications are discussed.

Theoretical studies of solar oscillations

NASA Technical Reports Server (NTRS)

Goldreich, P.

1980-01-01

Possible sources for the excitation of the solar 5 minute oscillations were investigated and a linear non-adiabatic stability code was applied to a preliminary study of the solar g-modes with periods near 160 minutes. Although no definitive conclusions concerning the excitation of these modes were reached, the excitation of the 5 minute oscillations by turbulent stresses in the convection zone remains a viable possibility. Theoretical calculations do not offer much support for the identification of the 160 minute global solar oscillation (reported by several independent observers) as a solar g-mode. A significant advance was made in attempting to reconcile mixing-length theory with the results of the calculations of linearly unstable normal modes. Calculations show that in a convective envelope prepared according to mixing length theory, the only linearly unstable modes are those which correspond to the turbulent eddies which are the basic element of the heuristic mixing length theory.

A review of models of fluctuating protrusion and retraction patterns at the leading edge of motile cells.

PubMed

Ryan, Gillian L; Watanabe, Naoki; Vavylonis, Dimitrios

2012-04-01

A characteristic feature of motile cells as they undergo a change in motile behavior is the development of fluctuating exploratory motions of the leading edge, driven by actin polymerization. We review quantitative models of these protrusion and retraction phenomena. Theoretical studies have been motivated by advances in experimental and computational methods that allow controlled perturbations, single molecule imaging, and analysis of spatiotemporal correlations in microscopic images. To explain oscillations and waves of the leading edge, most theoretical models propose nonlinear interactions and feedback mechanisms among different components of the actin cytoskeleton system. These mechanisms include curvature-sensing membrane proteins, myosin contraction, and autocatalytic biochemical reaction kinetics. We discuss how the combination of experimental studies with modeling promises to quantify the relative importance of these biochemical and biophysical processes at the leading edge and to evaluate their generality across cell types and extracellular environments. Copyright © 2012 Wiley Periodicals, Inc.

Solid State Division progress report for period ending September 30, 1993

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

Green, P.H.; Hinton, L.W.

1994-08-01

This report covers research progress in the Solid State Division from April 1, 1992, to September 30, 1993. During this period, the division conducted a broad, interdisciplinary materials research program with emphasis on theoretical solid state physics, neutron scattering, synthesis and characterization of materials, ion beam and laser processing, and the structure of solids and surfaces. This research effort was enhanced by new capabilities in atomic-scale materials characterization, new emphasis on the synthesis and processing of materials, and increased partnering with industry and universities. The theoretical effort included a broad range of analytical studies, as well as a new emphasismore » on numerical simulation stimulated by advances in high-performance computing and by strong interest in related division experimental programs. Superconductivity research continued to advance on a broad front from fundamental mechanisms of high-temperature superconductivity to the development of new materials and processing techniques. The Neutron Scattering Program was characterized by a strong scientific user program and growing diversity represented by new initiatives in complex fluids and residual stress. The national emphasis on materials synthesis and processing was mirrored in division research programs in thin-film processing, surface modification, and crystal growth. Research on advanced processing techniques such as laser ablation, ion implantation, and plasma processing was complemented by strong programs in the characterization of materials and surfaces including ultrahigh resolution scanning transmission electron microscopy, atomic-resolution chemical analysis, synchrotron x-ray research, and scanning tunneling microscopy.« less

An overview of the NASA Advanced Propulsion Concepts program

NASA Technical Reports Server (NTRS)

Curran, Francis M.; Bennett, Gary L.; Frisbee, Robert H.; Sercel, Joel C.; Lapointe, Michael R.

1992-01-01

NASA Advanced Propulsion Concepts (APC) program for the development of long-term space propulsion system schemes is managed by both NASA-Lewis and the JPL and is tasked with the identification and conceptual development of high-risk/high-payoff configurations. Both theoretical and experimental investigations have been undertaken in technology areas deemed essential to the implementation of candidate concepts. These APC candidates encompass very high energy density chemical propulsion systems, advanced electric propulsion systems, and an antiproton-catalyzed nuclear propulsion concept. A development status evaluation is presented for these systems.

Advanced Propulsion Physics Lab: Eagleworks Investigations

NASA Technical Reports Server (NTRS)

Scogin, Tyler

2014-01-01

Eagleworks Laboratory is an advanced propulsions physics laboratory with two primary investigations currently underway. The first is a Quantum Vacuum Plasma Thruster (QVPT or Q-thrusters), an advanced electric propulsion technology in the development and demonstration phase. The second investigation is in Warp Field Interferometry (WFI). This is an investigation of Dr. Harold "Sonny" White's theoretical physics models for warp field equations using optical experiments in the Electro Optical laboratory (EOL) at Johnson Space Center. These investigations are pursuing technology necessary to enable human exploration of the solar system and beyond.

Polarimetric Intensity Parameterization of Radar and Other Remote Sensing Sources for Advanced Exploitation and Data Fusion: Theory

DTIC Science & Technology

2008-10-01

is theoretically similar to the concept of “partial or compact polarimetry”, yields comparable results to full or quadrature-polarized systems by...to the emerging “compact polarimetry” methodology [9]-[13] that exploits scattering system response to an incomplete set of input EM field components...a scattering operator or matrix. Although as theoretically discussed earlier, performance of such fully-polarized radar system (i.e., quadrature

Workshop on High-Field NMR and Biological Applications

NASA Astrophysics Data System (ADS)

Scientists at the Pacific Northwest Laboratory have been working toward the establishment of a new Molecular Science Research Center (MSRC). The primary scientific thrust of this new research center is in the areas of theoretical chemistry, chemical dynamics, surface and interfacial science, and studies on the structure and interactions of biological macromolecules. The MSRC will provide important new capabilities for studies on the structure of biological macromolecules. The MSRC program includes several types of advanced spectroscopic techniques for molecular structure analysis, and a theory and modeling laboratory for molecular mechanics/dynamics calculations and graphics. It is the goal to closely integrate experimental and theoretical studies on macromolecular structure, and to join these research efforts with those of the molecular biological programs to provide new insights into the structure/function relationships of biological macromolecules. One of the areas of structural biology on which initial efforts in the MSRC will be focused is the application of high field, 2-D NMR to the study of biological macromolecules. First, there is interest in obtaining 3-D structural information on large proteins and oligonucleotides. Second, one of the primary objectives is to closely link theoretical approaches to molecular structure analysis with the results obtained in experimental research using NMR and other spectroscopies.

Advanced practice nurses' scope of practice: a qualitative study of advanced clinical competencies.

PubMed

Nieminen, Anna-Lena; Mannevaara, Bodil; Fagerström, Lisbeth

2011-12-01

To describe and explore Advanced Practice Nurses' clinical competencies and how these are expressed in clinical practice. Discussion concerning advanced clinical practice has been ongoing in the USA since the 1960s and in the UK since the late 1980s. Approximately 24 countries, excluding the USA, have implemented the role of Advance Practice Nurse (APN). In the Nordic countries, especially Sweden and Finland, APNs have been introduced in some organizations but their competency domains have not yet been clearly defined. The study's theoretical framework emanates from Aristotle's three-dimensional view of knowledge that is epistêmê, technê, and phronesis. Between October 2005 and January 2006, focus group interviews of Clinical Nurse Specialists who provide expert functions in pediatric, internal medicine, and surgical units (n = 26) and APN students (n = 8) were conducted. The data material was analyzed using inductive content analysis. Grouped into five main themes, the study results indicate that APNs possess advanced level clinical competencies in: (A) assessment of patients' caring needs and nursing care activities, (B) the caring relationship, (C) multi-professional teamwork, (D) development of competence and nursing care, and (E) leadership in a learning and caring culture. Clinical competencies consist of advanced skills, which typify an expanding role that offers new possibilities for holistic patient care practice. APNs' scope of practice is characterized by responsibility and competence in making autonomous judgments based on expanded clinical competence. On an advanced level, clinical competence consists not merely of advanced skills for assessing and meeting the needs of patients but also the creation of safe and trustful relationships with patients and collaboration with colleagues. APNs can realize advanced skills in their actions through their manner of knowing, doing, and being. © 2011 The Authors. Scandinavian Journal of Caring Sciences © 2011 Nordic College of Caring Science.

Conferences, workshops, trainings

Science.gov Websites

of pulsars and other gamma-rays sources; ii) experimental data from the HAWC and other cosmic rays Advancements in immunology can be made through the development of theoretical and experimental techniques

Investigation of Perceptual-Motor Behavior Across the Expert Athlete to Disabled Patient Skill Continuum can Advance Theory and Practical Application.

PubMed

Müller, Sean; Vallence, Ann-Maree; Winstein, Carolee

2017-12-14

A framework is presented of how theoretical predictions can be tested across the expert athlete to disabled patient skill continuum. Common-coding theory is used as the exemplar to discuss sensory and motor system contributions to perceptual-motor behavior. Behavioral and neural studies investigating expert athletes and patients recovering from cerebral stroke are reviewed. They provide evidence of bi-directional contributions of visual and motor systems to perceptual-motor behavior. Majority of this research is focused on perceptual-motor performance or learning, with less on transfer. The field is ripe for research designed to test theoretical predictions across the expert athlete to disabled patient skill continuum. Our view has implications for theory and practice in sports science, physical education, and rehabilitation.

The measurement of drug craving

PubMed Central

Sayette, Michael A.; Shiffman, Saul; Tiffany, Stephen T.; Niaura, Raymond S.; Martin, Christopher S.; Shadel, William G.

2009-01-01

This paper reviews theoretical and methodological issues in the measurement of drug craving, with an emphasis on self-report assessment. Despite the important role that craving plays in many research and clinical settings, the way in which the construct is conceptualized and measured rarely receives sufficient attention. Issues pertinent to conceptualizing craving are identified. Because there is no single perfect measure of craving, it is essential that researchers understand the limitations of each measure. Measurement performance concerns that affect the validity of different measures are reviewed. Non-verbal assessment methods are also reviewed. Research factors that may help determine the optimal measures for a given study are highlighted. It is concluded that advances in assessment will proceed only when combined with additional research and a better theoretical understanding of craving. PMID:11002914

A novel optic bistable device with very low threshold intensity using photorefractive films

NASA Astrophysics Data System (ADS)

Wang, Sean X.; Sun, Yuankun; Trivedi, Sudhir B.; Li, Guifang

1994-08-01

Brimrose Corporation of America reports the successful completion of the SBIR Phase I research in low-threshold intensity optical bistable devices using photorefractive nonlinearity. A thin photorefractive film optical bistable device was proposed in the Phase I proposal. The feasibility of this device was theoretically investigated. The theoretical feasibility study formulates the materials requirements in such a kind of configuration for Phase II research. In addition, we have proposed and investigated another configuration of optical bistable devices that do not require advanced photorefractive materials, namely, the self-pumped phase conjugator. We have successfully demonstrated a low-threshold optical bistable operation in a KNSBN:CU crystal. To the best of our knowledge, the threshold of 650 mW/sq. cm is the lowest of its kind to be achieved so far.

The reconstitution of political theory: David Easton, behavioralism, and the long road to system.

PubMed

Gunnell, John G

2013-01-01

During the last half of the twentieth century, the concept of system was arguably the most important concept in the theoretical repertoire of the discipline of American political science. Although systems analysis was broadly employed in the behavioral sciences, David Easton's work was particularly influential in the study of politics. This is in part because he attempted to develop a distinct account of the political system that was not theoretically subservient either to general systems theory or to conceptions of the social system such as that advanced by Talcott Parsons. Although a great deal of attention has been devoted to Easton's theory, the origins and evolution of the system concept in his work have not been carefully reconstructed and analyzed. © 2013 Wiley Periodicals, Inc.

Microcirculation and the physiome projects.

PubMed

Bassingthwaighte, James B

2008-11-01

The Physiome projects comprise a loosely knit worldwide effort to define the Physiome through databases and theoretical models, with the goal of better understanding the integrative functions of cells, organs, and organisms. The projects involve developing and archiving models, providing centralized databases, and linking experimental information and models from many laboratories into self-consistent frameworks. Increasingly accurate and complete models that embody quantitative biological hypotheses, adhere to high standards, and are publicly available and reproducible, together with refined and curated data, will enable biological scientists to advance integrative, analytical, and predictive approaches to the study of medicine and physiology. This review discusses the rationale and history of the Physiome projects, the role of theoretical models in the development of the Physiome, and the current status of efforts in this area addressing the microcirculation.

Tools for the Microbiome: Nano and Beyond.

PubMed

Biteen, Julie S; Blainey, Paul C; Cardon, Zoe G; Chun, Miyoung; Church, George M; Dorrestein, Pieter C; Fraser, Scott E; Gilbert, Jack A; Jansson, Janet K; Knight, Rob; Miller, Jeff F; Ozcan, Aydogan; Prather, Kimberly A; Quake, Stephen R; Ruby, Edward G; Silver, Pamela A; Taha, Sharif; van den Engh, Ger; Weiss, Paul S; Wong, Gerard C L; Wright, Aaron T; Young, Thomas D

2016-01-26

The microbiome presents great opportunities for understanding and improving the world around us and elucidating the interactions that compose it. The microbiome also poses tremendous challenges for mapping and manipulating the entangled networks of interactions among myriad diverse organisms. Here, we describe the opportunities, technical needs, and potential approaches to address these challenges, based on recent and upcoming advances in measurement and control at the nanoscale and beyond. These technical needs will provide the basis for advancing the largely descriptive studies of the microbiome to the theoretical and mechanistic understandings that will underpin the discipline of microbiome engineering. We anticipate that the new tools and methods developed will also be more broadly useful in environmental monitoring, medicine, forensics, and other areas.

Improvements to Nuclear Data and Its Uncertainties by Theoretical Modeling

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

Danon, Yaron; Nazarewicz, Witold; Talou, Patrick

2013-02-18

This project addresses three important gaps in existing evaluated nuclear data libraries that represent a significant hindrance against highly advanced modeling and simulation capabilities for the Advanced Fuel Cycle Initiative (AFCI). This project will: Develop advanced theoretical tools to compute prompt fission neutrons and gamma-ray characteristics well beyond average spectra and multiplicity, and produce new evaluated files of U and Pu isotopes, along with some minor actinides; Perform state-of-the-art fission cross-section modeling and calculations using global and microscopic model input parameters, leading to truly predictive fission cross-sections capabilities. Consistent calculations for a suite of Pu isotopes will be performed; Implementmore » innovative data assimilation tools, which will reflect the nuclear data evaluation process much more accurately, and lead to a new generation of uncertainty quantification files. New covariance matrices will be obtained for Pu isotopes and compared to existing ones. The deployment of a fleet of safe and efficient advanced reactors that minimize radiotoxic waste and are proliferation-resistant is a clear and ambitious goal of AFCI. While in the past the design, construction and operation of a reactor were supported through empirical trials, this new phase in nuclear energy production is expected to rely heavily on advanced modeling and simulation capabilities. To be truly successful, a program for advanced simulations of innovative reactors will have to develop advanced multi-physics capabilities, to be run on massively parallel super- computers, and to incorporate adequate and precise underlying physics. And all these areas have to be developed simultaneously to achieve those ambitious goals. Of particular interest are reliable fission cross-section uncertainty estimates (including important correlations) and evaluations of prompt fission neutrons and gamma-ray spectra and uncertainties.« less

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

PubMed

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

2017-08-01

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

The design and demonstration of an advanced data collection/position locating system, addendum. [coherent demodulator

NASA Technical Reports Server (NTRS)

1978-01-01

The theoretical background for a coherent demodulator for minimum shift keying signals generated by the advanced data collection/position locating system breadboard is presented along with a discussion of the design concept. Various tests and test results, obtained with the breadboard system described, include evaluation of bit-error rate performance, acquisition time, clock recovery, recycle time, frequency measurement accuracy, and mutual interference.

An analytical study for the design of advanced rotor airfoils

NASA Technical Reports Server (NTRS)

Kemp, L. D.

1973-01-01

A theoretical study has been conducted to design and evaluate two airfoils for helicopter rotors. The best basic shape, designed with a transonic hodograph design method, was modified to meet subsonic criteria. One airfoil had an additional constraint for low pitching-moment at the transonic design point. Airfoil characteristics were predicted. Results of a comparative analysis of helicopter performance indicate that the new airfoils will produce reduced rotor power requirements compared to the NACA 0012. The hodograph design method, written in CDC Algol, is listed and described.

New directions for nanoscale thermoelectric materials research

NASA Technical Reports Server (NTRS)

Dresselhaus, M. S.; Chen, G.; Tang, M. Y.; Yang, R. G.; Lee, H.; Wang, D. Z.; Ren, F.; Fleurial, J. P.; Gogna, P.

2005-01-01

Many of the recent advances in enhancing the thermoelectric figure of merit are linked to nanoscale phenomena with both bulk samples containing nanoscale constituents and nanoscale materials exhibiting enhanced thermoelectric performance in their own right. Prior theoretical and experimental proof of principle studies on isolated quantum well and quantum wire samples have now evolved into studies on bulk samples containing nanostructured constituents. In this review, nanostructural composites are shown to exhibit nanostructures and properties that show promise for thermoelectric applications. A review of some of the results obtained to date are presented.

Synthesis, antimicrobial activity and advances in structure-activity relationships (SARs) of novel tri-substituted thiazole derivatives.

PubMed

Reddy, Guda Mallikarjuna; Garcia, Jarem Raul; Reddy, Vemulapati Hanuman; de Andrade, Ageo Meier; Camilo, Alexandre; Pontes Ribeiro, Renan Augusto; de Lazaro, Sergio Ricardo

2016-11-10

Trisubstituted thiazoles were synthesized and studied for their antimicrobial activity and supported by theoretical calculations. In addition, MIC, MBC and MFC were also tested. Moreover, the present study was analyzed to scrutinize comprehensive structure-activity relationships. In fact, LUMO orbital energy and orbital orientation was reliable to explain their antibacterial and antifungal assay. Amongst the tested compounds, tri-methyl-substituted thiazole compound showed higher antimicrobial activity and low MIC value due to highest LUMO energy. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Random Variables: Simulations and Surprising Connections.

ERIC Educational Resources Information Center

Quinn, Robert J.; Tomlinson, Stephen

1999-01-01

Features activities for advanced second-year algebra students in grades 11 and 12. Introduces three random variables and considers an empirical and theoretical probability for each. Uses coins, regular dice, decahedral dice, and calculators. (ASK)

Fermilab | Science at Fermilab | Theory

Science.gov Websites

future direction of experimental programs. Experimental results, in turn, can confirm or rule out GPS satellites, rely on the advances made in experimental and theoretical physics. Without a firm

Status of LWIR HgCdTe infrared detector technology

NASA Technical Reports Server (NTRS)

Reine, M. B.

1990-01-01

The performance requirements that today's advanced Long Wavelength Infrared (LWIR) focal plane arrays place on the HgCdTe photovoltaic detector array are summarized. The theoretical performance limits for intrinsic LWIR HgCdTe detectors are reviewed as functions of cutoff wavelength and operating temperature. The status of LWIR HgCdTe photovoltaic detectors is reviewed and compared to the focal plane array (FPA) requirements and to the theoretical limits. Emphasis is placed on recent data for two-layer HgCdTe PLE heterojunction photodiodes grown at Loral with cutoff wavelengths ranging between 10 and 19 microns at temperatures of 70 to 80 K. Development trends in LWIR HgCdTe detector technology are outlined, and conclusions are drawn about the ability for photovoltaic HgCdTe detector arrays to satisfy a wide variety of advanced FPA array applications.

Theoretical study of the self-assembly of Janus Bottlebrush Polymers from A-Branch-B Diblock Macromonomers

NASA Astrophysics Data System (ADS)

Gadelrab, Karim; Alexander-Katz, Alfredo; LaboratoryTheoretical Soft Materials Team

The self-assembly of block copolymers BCP has provided an impressive control over the nanoscale structure of soft matter. While the main focus of the research in the field has been directed towards simple linear diblocks, the development of advanced polymer architecture provided improved performance and access to new structures. In particular, bottlebrush BCPs (BBCPs) have interesting characteristics due to their dense functionality, high molecular weight, low levels of entanglement, and tendency to efficiently undergo rapid bulk phase separation. In this work, we are interested in theoretically studying the self-assembly of Janus-type ``A-branch-B'' BBCPs where A and B blocks can phase separate with the bottlebrush polymer backbone serving as the interface between the two blocks. Hence, the polymer backbone adds an extra constraint on the equilibrium spacing between neighboring linear diblock chains. In this regard, the segment length of the backbone separating the AB junctions has a direct effect of the observed domain spacing and effective segregation strength of the AB blocks. We employ self-consistent field theoretic SCFT simulations to capture the effect of volume fraction of different constituents and construct a phase diagram of the accessible morphologies of these BBCPs.

Fine-grained semantic categorization across the abstract and concrete domains.

PubMed

Ghio, Marta; Vaghi, Matilde Maria Serena; Tettamanti, Marco

2013-01-01

A consolidated approach to the study of the mental representation of word meanings has consisted in contrasting different domains of knowledge, broadly reflecting the abstract-concrete dichotomy. More fine-grained semantic distinctions have emerged in neuropsychological and cognitive neuroscience work, reflecting semantic category specificity, but almost exclusively within the concrete domain. Theoretical advances, particularly within the area of embodied cognition, have more recently put forward the idea that distributed neural representations tied to the kinds of experience maintained with the concepts' referents might distinguish conceptual meanings with a high degree of specificity, including those within the abstract domain. Here we report the results of two psycholinguistic rating studies incorporating such theoretical advances with two main objectives: first, to provide empirical evidence of fine-grained distinctions within both the abstract and the concrete semantic domains with respect to relevant psycholinguistic dimensions; second, to develop a carefully controlled linguistic stimulus set that may be used for auditory as well as visual neuroimaging studies focusing on the parametrization of the semantic space beyond the abstract-concrete dichotomy. Ninety-six participants rated a set of 210 sentences across pre-selected concrete (mouth, hand, or leg action-related) and abstract (mental state-, emotion-, mathematics-related) categories, with respect either to different semantic domain-related scales (rating study 1), or to concreteness, familiarity, and context availability (rating study 2). Inferential statistics and correspondence analyses highlighted distinguishing semantic and psycholinguistic traits for each of the pre-selected categories, indicating that a simple abstract-concrete dichotomy is not sufficient to account for the entire semantic variability within either domains.

Fine-Grained Semantic Categorization across the Abstract and Concrete Domains

PubMed Central

Tettamanti, Marco

2013-01-01

A consolidated approach to the study of the mental representation of word meanings has consisted in contrasting different domains of knowledge, broadly reflecting the abstract-concrete dichotomy. More fine-grained semantic distinctions have emerged in neuropsychological and cognitive neuroscience work, reflecting semantic category specificity, but almost exclusively within the concrete domain. Theoretical advances, particularly within the area of embodied cognition, have more recently put forward the idea that distributed neural representations tied to the kinds of experience maintained with the concepts' referents might distinguish conceptual meanings with a high degree of specificity, including those within the abstract domain. Here we report the results of two psycholinguistic rating studies incorporating such theoretical advances with two main objectives: first, to provide empirical evidence of fine-grained distinctions within both the abstract and the concrete semantic domains with respect to relevant psycholinguistic dimensions; second, to develop a carefully controlled linguistic stimulus set that may be used for auditory as well as visual neuroimaging studies focusing on the parametrization of the semantic space beyond the abstract-concrete dichotomy. Ninety-six participants rated a set of 210 sentences across pre-selected concrete (mouth, hand, or leg action-related) and abstract (mental state-, emotion-, mathematics-related) categories, with respect either to different semantic domain-related scales (rating study 1), or to concreteness, familiarity, and context availability (rating study 2). Inferential statistics and correspondence analyses highlighted distinguishing semantic and psycholinguistic traits for each of the pre-selected categories, indicating that a simple abstract-concrete dichotomy is not sufficient to account for the entire semantic variability within either domains. PMID:23825625

Neural Signatures of Autism Spectrum Disorders: Insights into Brain Network Dynamics

PubMed Central

Hernandez, Leanna M; Rudie, Jeffrey D; Green, Shulamite A; Bookheimer, Susan; Dapretto, Mirella

2015-01-01

Neuroimaging investigations of autism spectrum disorders (ASDs) have advanced our understanding of atypical brain function and structure, and have recently converged on a model of altered network-level connectivity. Traditional task-based functional magnetic resonance imaging (MRI) and volume-based structural MRI studies have identified widespread atypicalities in brain regions involved in social behavior and other core ASD-related behavioral deficits. More recent advances in MR-neuroimaging methods allow for quantification of brain connectivity using diffusion tensor imaging, functional connectivity, and graph theoretic methods. These newer techniques have moved the field toward a systems-level understanding of ASD etiology, integrating functional and structural measures across distal brain regions. Neuroimaging findings in ASD as a whole have been mixed and at times contradictory, likely due to the vast genetic and phenotypic heterogeneity characteristic of the disorder. Future longitudinal studies of brain development will be crucial to yield insights into mechanisms of disease etiology in ASD sub-populations. Advances in neuroimaging methods and large-scale collaborations will also allow for an integrated approach linking neuroimaging, genetics, and phenotypic data. PMID:25011468

An Atomistic-Scale Study for Thermal Conductivity and Thermochemical Compatibility in (DyY)Zr2O7 Combining an Experimental Approach with Theoretical Calculation.

PubMed

Qu, Liu; Choy, Kwang-Leong; Wheatley, Richard

2016-02-18

Ceramic oxides that have high-temperature capabilities can be deposited on the superalloy components in aero engines and diesel engines to advance engine efficiency and reduce fuel consumption. This paper aims to study doping effects of Dy(3+) and Y(3+)on the thermodynamic properties of ZrO2 synthesized via a sol-gel route for a better control of the stoichiometry, combined with molecular dynamics (MD) simulation for the calculation of theoretical properties. The thermal conductivity is investigated by the MD simulation and Clarke's model. This can improve the understanding of the microstructure and thermodynamic properties of (DyY)Zr2O7 (DYZ) at the atomistic level. The phonon-defect scattering and phonon-phonon scattering processes are investigated via the theoretical calculation, which provides an effective way to study thermal transport properties of ionic oxides. The measured and predicted thermal conductivity of DYZ is lower than that of 4 mol % Y2O3 stabilized ZrO2 (4YSZ). It is discovered that DYZ is thermochemically compatible with Al2O3 at 1300 °C, whereas at 1350 °C DYZ reacts with Al2O3 forming a small amount of new phases.

An Atomistic-Scale Study for Thermal Conductivity and Thermochemical Compatibility in (DyY)Zr2O7 Combining an Experimental Approach with Theoretical Calculation

PubMed Central

Qu, Liu; Choy, Kwang-Leong; Wheatley, Richard

2016-01-01

Ceramic oxides that have high-temperature capabilities can be deposited on the superalloy components in aero engines and diesel engines to advance engine efficiency and reduce fuel consumption. This paper aims to study doping effects of Dy3+ and Y3+on the thermodynamic properties of ZrO2 synthesized via a sol-gel route for a better control of the stoichiometry, combined with molecular dynamics (MD) simulation for the calculation of theoretical properties. The thermal conductivity is investigated by the MD simulation and Clarke’s model. This can improve the understanding of the microstructure and thermodynamic properties of (DyY)Zr2O7 (DYZ) at the atomistic level. The phonon-defect scattering and phonon-phonon scattering processes are investigated via the theoretical calculation, which provides an effective way to study thermal transport properties of ionic oxides. The measured and predicted thermal conductivity of DYZ is lower than that of 4 mol % Y2O3 stabilized ZrO2 (4YSZ). It is discovered that DYZ is thermochemically compatible with Al2O3 at 1300 °C, whereas at 1350 °C DYZ reacts with Al2O3 forming a small amount of new phases. PMID:26888438

A study of kindergarten children's spatial representation in a mapping project

NASA Astrophysics Data System (ADS)

Davis, Genevieve A.; Hyun, Eunsook

2005-02-01

This phenomenological study examined kindergarten children's development of spatial representation in a year long mapping project. Findings and discussion relative to how children conceptualised and represented physical space are presented in light of theoretical notions advanced by Piaget, van Hiele, and cognitive science researchers Battista and Clements. Analyses of the processes the children used and their finished products indicate that children can negotiate meaning for complex systems of geometric concepts when given opportunities to debate, negotiate, reflect, evaluate and seek meaning for representing space. The complexity and "holistic" nature of spatial representation of young children emerged in this study.

A Study of Tourism Dynamics in Three Italian Regions Using a Nonautonomous Integrable Lotka–Volterra Model

PubMed Central

Romano, Alessandro

2016-01-01

This article is a first application of an integrable nonautonomous Lotka–Volterra (LV) model to the study of tourism dynamics. In particular, we analyze the interaction in terms of touristic flows among three Italian regions. Confirming an hypothesis advanced by recent theoretical works, we find that these regions not only compete against each other, but at times they also proceed in mutualism. Moreover, the kind and the intensity of the interaction changes over time, suggesting that dynamic models can play a vital role in the study of touristic flows. PMID:27661615

Cosmochemistry: Understanding the Solar System through analysis of extraterrestrial materials.

PubMed

MacPherson, Glenn J; Thiemens, Mark H

2011-11-29

Cosmochemistry is the chemical analysis of extraterrestrial materials. This term generally is taken to mean laboratory analysis, which is the cosmochemistry gold standard because of the ability for repeated analysis under highly controlled conditions using the most advanced instrumentation unhindered by limitations in power, space, or environment. Over the past 40 y, advances in technology have enabled telescopic and spacecraft instruments to provide important data that significantly complement the laboratory data. In this special edition, recent advances in the state of the art of cosmochemistry are presented, which range from instrumental analysis of meteorites to theoretical-computational and astronomical observations.

Progress in Earth System Modeling since the ENIAC Calculation

NASA Astrophysics Data System (ADS)

Fung, I.

2009-05-01

The success of the first numerical weather prediction experiment on the ENIAC computer in 1950 was hinged on the expansion of the meteorological observing network, which led to theoretical advances in atmospheric dynamics and subsequently the implementation of the simplified equations on the computer. This paper briefly reviews the progress in Earth System Modeling and climate observations, and suggests a strategy to sustain and expand the observations needed to advance climate science and prediction.

Morphosyntactic Processing in Advanced Second Language (L2) Learners: An Event-Related Potential Investigation of the Effects of L1-l2 Similarity and Structural Distance

ERIC Educational Resources Information Center

Alemán Bañón, José; Fiorentino, Robert; Gabriele, Alison

2014-01-01

Different theoretical accounts of second language (L2) acquisition differ with respect to whether or not advanced learners are predicted to show native-like processing for features not instantiated in the native language (L1). We examined how native speakers of English, a language with number but not gender agreement, process number and gender…

Gravity, Magnetic and Electromagnetic Gradiometry; Strategic technologies in the 21st century

NASA Astrophysics Data System (ADS)

Veryaskin, Alexey V.

2018-02-01

Gradiometry is a multidisciplinary area that combines theoretical and applied physics, ultra-low noise electronics, precision engineering, and advanced signal processing. Applications include the search for oil, gas, and mineral resources, GPS-free navigation, defence, space missions, and medical research. This book provides readers with a comprehensive introduction, history, potential applications, and current developments in relation to some of the most advanced technologies in the 21st Century.

Novel technologies and theoretical models in radiation therapy of cancer patients using 6.3 MeV fast neutrons produced by U-120 cyclotron

NASA Astrophysics Data System (ADS)

Musabaeva, L. I.; Startseva, Zh. A.; Gribova, O. V.; Velikaya, V. V.; Lisin, V. A.

2016-08-01

The analysis of clinical use of neutron therapy with 6 MeV fast neutrons compared to conventional radiation therapy was carried out. The experience of using neutron and mixed neutron and photon therapy in patients with different radio-resistant malignant tumors shows the necessity of further studies and development of the novel approaches to densely-ionizing radiation. The results of dosimetry and radiobiological studies have been the basis for planning clinical programs for neutron therapy. Clinical trials over the past 30 years have shown that neutron therapy successfully destroys radio-resistant cancers, including salivary gland tumors, adenoidcystic carcinoma, inoperable sarcomas, locally advanced head and neck tumors, and locally advanced prostate cancer. Radiation therapy with 6.3 MeV fast neutrons used alone and in combination with photon therapy resulted in improved long-term treatment outcomes in patients with radio-resistant malignant tumors.

Ion cyclotron emission studies: Retrospects and prospects

DOE PAGES

Gorelenkov, N. N.

2016-06-05

Ion cyclotron emission (ICE) studies emerged in part from the papers by A.B. Mikhailovskii published in the 1970s. Among the discussed subjects were electromagnetic compressional Alfv,nic cyclotron instabilities with the linear growth rate similar ~ √(n α/n e) driven by fusion products, -particles which draw a lot of attention to energetic particle physics. The theory of ICE excited by energetic particles was significantly advanced at the end of the 20th century motivated by first DT experiments on TFTR and subsequent JET experimental studies which we highlight. Recently ICE theory was advanced by detailed theoretical and experimental studies on spherical torusmore » (ST) fusion devices where the instability signals previously indistinguishable in high aspect ratio tokamaks due to high toroidal magnetic field became the subjects of experiments. Finally, we discuss prospects of ICE theory applications for future burning plasma (BP) experiments such as those to be conducted in ITER device in France, where neutron and gamma rays escaping the plasma create extremely challenging conditions fusion alpha particle diagnostics.« less

Ion cyclotron emission studies: Retrospects and prospects

NASA Astrophysics Data System (ADS)

Gorelenkov, N. N.

2016-05-01

Ion cyclotron emission (ICE) studies emerged in part from the papers by A.B. Mikhailovskii published in the 1970s. Among the discussed subjects were electromagnetic compressional Alfvénic cyclotron instabilities with the linear growth rate √ {n_α /n_e } driven by fusion products, -particles which draw a lot of attention to energetic particle physics. The theory of ICE excited by energetic particles was significantly advanced at the end of the 20th century motivated by first DT experiments on TFTR and subsequent JET experimental studies which we highlight. More recently ICE theory was advanced by detailed theoretical and experimental studies on spherical torus (ST) fusion devices where the instability signals previously indistinguishable in high aspect ratio tokamaks due to high toroidal magnetic field became the subjects of experiments. We discuss further prospects of ICE theory applications for future burning plasma (BP) experiments such as those to be conducted in ITER device in France, where neutron and gamma rays escaping the plasma create extremely challenging conditions fusion alpha particle diagnostics.

Theoretical links supporting the use of problem-based learning in the education of the nurse practitioner.

PubMed

Chikotas, Noreen Elaine

2008-01-01

The need to evaluate current strategies in educating the advanced practice nurse, specifically the nurse practitioner, is becoming more and more imperative due to the ever-changing health care environment. This article addresses the role of problem-based learning (PBL) as an instructional strategy in educating and preparing the nurse practitioner for future practice.Two theoretical frameworks supporting PBL, andragogy and constructivism, are presented as important to the use of PBL in the education of the nurse practitioner.

ARPA/NRL X-Ray Laser Program - Semiannual Technical Report to Defense Advanced Research Projects Agency, 1 Jul 1974-31 December 1974

DTIC Science & Technology

1975-05-01

Finally, diagnostics for quantitative measurements of all these properties are necessary for meaningful comparison of the experiments with theoretical ...width (FWHM) of 120 ^rad. For comparison, a beam which fills the last amplifier rod has a corresponding theoretical divergence angle of 108 urad...hydrogen the protons produced by photoionization do not absorb). Also shown are the spontaneous lifetimes tu of the upper laser level, of use for self

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

PubMed Central

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

2017-01-01

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

Early and transient stages of Cu oxidation: Atomistic insights from theoretical simulations and in situ experiments

NASA Astrophysics Data System (ADS)

Zhu, Qing; Zou, Lianfeng; Zhou, Guangwen; Saidi, Wissam A.; Yang, Judith C.

2016-10-01

Understanding of metal oxidation is critical to corrosion control, catalysis synthesis, and advanced materials engineering. Although, metal oxidation process is rather complicated, different processes, many of them coupled, are involved from the onset of reaction. Since first introduced, there has been great success in applying heteroepitaxial theory to the oxide growth on a metal surface as demonstrated in the Cu oxidation experiments. In this paper, we review the recent progress in experimental findings on Cu oxidation as well as the advances in the theoretical simulations of the Cu oxidation process. We focus on the effects of defects such as step edges, present on realistic metal surfaces, on the oxide growth dynamics. We show that the surface steps can change the mass transport of both Cu and O atoms during oxide growth, and ultimately lead to the formation of different oxide morphology. We also review the oxidation of Cu alloys and explore the effect of a secondary element to the oxide growth on a Cu surface. From the review of the work on Cu oxidation, we demonstrate the correlation of theoretical simulations at multiple scales with various experimental techniques.

Quantum properties of light emitted by dipole nano-laser

NASA Astrophysics Data System (ADS)

Ghannam, Talal

Recent technological advances allow entire optical systems to be lithographically implanted on small silicon chips. These systems include tiny semiconductor lasers that function as light sources for digital optical signals. Future advances will rely on even smaller components. At the theoretical limit of this process, the smallest lasers will have an active medium consisting of a single atom (natural or artificial). Several suggestions for how this can be accomplished have already been published, such as nano-lasers based on photonic crystals and nano wires. In particular, the "dipole nanolaser" consists of a single quantum dot functioning as the active medium. It is optically coupled to a metal nanoparticles that form a resonant cavity. Laser light is generated from the near-field optical signal. The proposed work is a theoretical exploration of the nature of the resulting laser light. The dynamics of the system will be studied and relevant time scales described. These will form the basis for a set of operator equations describing the quantum properties of the emitted light. The dynamics will be studied in both density matrix and quantum Langevin formulations, with attention directed to noise sources. The equations will be linearized and solved using standard techniques. The result of the study will be a set of predicted noise spectra describing the statistics of the emitted light. The goal will be to identify the major noise contributions and suggest methods for suppressing them. This will be done by studying the probability of getting squeezed light from the nanoparticle for the certain scheme of parameters.

Coupling biology and oceanography in models.

PubMed

Fennel, W; Neumann, T

2001-08-01

The dynamics of marine ecosystems, i.e. the changes of observable chemical-biological quantities in space and time, are driven by biological and physical processes. Predictions of future developments of marine systems need a theoretical framework, i.e. models, solidly based on research and understanding of the different processes involved. The natural way to describe marine systems theoretically seems to be the embedding of chemical-biological models into circulation models. However, while circulation models are relatively advanced the quantitative theoretical description of chemical-biological processes lags behind. This paper discusses some of the approaches and problems in the development of consistent theories and indicates the beneficial potential of the coupling of marine biology and oceanography in models.

1983 AFOSR/AFRPL Chemical Rocket Research Meeting, Abstracts and Agenda. Includes: Abstracts on Advanced Diagnostics of Reacting Flow, 28 February - 3 March 1983, Lancaster, California.

DTIC Science & Technology

1983-02-01

blow-off stability and fractional conversion was evaluated for design of an experimental study of these phenomena. The apparatus designed will be...the development of an array of experimental methods and test strategies designed to unravel a complex process that is very difficult to observe directly...this effort of lead field theoretic analysis as a design basis has made that possible. The experimental phase of the effort has three major

Advances in the Theory of Complex Networks

NASA Astrophysics Data System (ADS)

Peruani, Fernando

An exhaustive and comprehensive review on the theory of complex networks would imply nowadays a titanic task, and it would result in a lengthy work containing plenty of technical details of arguable relevance. Instead, this chapter addresses very briefly the ABC of complex network theory, visiting only the hallmarks of the theoretical founding, to finally focus on two of the most interesting and promising current research problems: the study of dynamical processes on transportation networks and the identification of communities in complex networks.

Free turbulent shear flows. Volume 2: Summary of data

NASA Technical Reports Server (NTRS)

Birch, S. F.

1973-01-01

The proceedings of a conference on free turbulent shear flows are presented. Objectives of the conference are as follows: (1) collect and process data for a variety of free mixing problems, (2) assess present theoretical capability for predicting mean velocity, concentration, and temperature distributions in free turbulent flows, (3) identify and recommend experimental studies to advance knowledge of free shear flows, and (4) increase understanding of basic turbulent mixing process for application to free shear flows. Examples of specific cases of jet flow are included.

Martin J. Klein: From Physicist to Historian

NASA Astrophysics Data System (ADS)

Hu, Danian

2012-12-01

To his friends, colleagues, and students, Martin Klein was a gentle and modest man of extraordinary integrity whose stellar accomplishments garnered him many honors. I sketch his life and career, in which he transformed himself from a theoretical physicist at Columbia University, the Massachusetts Institute of Technology, and the Case Institute of Technology into a historian of physics while on leave at the Dublin Institute for Advanced Study and the University of Leiden and then pursued this field full time at Yale University.

Magnetospheric radio and plasma wave research - 1987-1990

NASA Technical Reports Server (NTRS)

Kurth, W. S.

1991-01-01

This review covers research performed in the area of magnetospheric plasma waves and wave-particle interactions as well as magnetospheric radio emissions. The report focuses on the near-completion of the discovery phase of radio and plasma wave phenomena in the planetary magnetospheres with the successful completion of the Voyager 2 encounters of Neptune and Uranus. Consideration is given to the advances made in detailed studies and theoretical investigations of radio and plasma wave phenomena in the terrestrial magnetosphere or in magnetospheric plasmas in general.

Sodium MRI: Methods and applications

PubMed Central

Madelin, Guillaume; Lee, Jae-Seung; Regatte, Ravinder R.; Jerschow, Alexej

2014-01-01

Sodium NMR spectroscopy and MRI have become popular in recent years through the increased availability of high-field MRI scanners, advanced scanner hardware and improved methodology. Sodium MRI is being evaluated for stroke and tumor detection, for breast cancer studies, and for the assessment of osteoarthritis and muscle and kidney functions, to name just a few. In this article, we aim to present an up-to-date review of the theoretical background, the methodology, the challenges and limitations, and current and potential new applications of sodium MRI. PMID:24815363

Introduction to Part I

NASA Astrophysics Data System (ADS)

Strocchi, Franco

These notes essentially reproduce lectures given at the International School for Advanced Studies (Trieste) and at the Scuola Normale Superiore (Pisa) on various occasions. The scope of the short series of lectures, typically a fraction of a one-semester course, was to explain on general grounds, also to mathematicians, the phenomenon of Spontaneous Symmetry Breaking (SSB), a mechanism which seems at the basis of most of the recent developments in theoretical physics (from Statistical Mechanics to Many-Body theory and to Elementary Particle theory).

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

PubMed

Wang, Chih-Ying; Hill, Reghan J

2014-11-18

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

A comparison of naïve and sophisticated subject behavior with game theoretic predictions

PubMed Central

McCabe, Kevin A.; Smith, Vernon L.

2000-01-01

We use an extensive form two-person game as the basis for two experiments designed to compare the behavior of two groups of subjects with each other and with the subgame perfect theoretical prediction in an anonymous interaction protocol. The two subject groups are undergraduates and advanced graduate students, the latter having studied economics and game theory. There is no difference in their choice behavior, and both groups depart substantially from game theoretic predictions. We also compare a subsample of the same graduate students with a typical undergraduate sample in an asset trading environment in which inexperienced undergraduates invariably produce substantial departures from the rational expectations prediction. In this way, we examine how robust are the results across two distinct anonymous interactive environments. In the constant sum trading game, the graduate students closely track the predictions of rational theory. Our interpretation is that the graduate student subjects' departure from subgame perfection to achieve cooperative outcomes in the two-person bargaining game is a consequence of a deliberate strategy and is not the result of error or inadequate learning. PMID:10725349

Pragmatic critical realism: could this methodological approach expand our understanding of employment relations?

PubMed

Mearns, Susan Lesley

2011-01-01

This paper seeks to highlight the need for employment relations academics and researchers to expand their use of research methodologies in order for them to enable the advancement of theoretical debate within their discipline. It focuses on the contribution that pragmatical critical realism has made to the field of perception and argues that it would add value to the subject of employment relations. It is a theoretically centred review of pragmatical critical realism and the possible contribution this methodology would make to the field of employment relations. The paper concludes that the employment relationship does not take place in a vacuum rather it is focussed on the interaction between imperfect individuals. Therefore, their interactions are moulded by emotions which can not be explored thoroughly or even acknowledged through a positivists' rigorous but limited acknowledgment of what constitutes 'knowledge' and development of theory. While not rejecting the contribution that quantitative data or positivism have made to the field, the study concludes that pragmatic critical realism has a lot to offer the development of the area and its theoretical foundations.

Isolation and spectral characterization of thermally generated multi-Z-isomers of lycopene and the theoretically preferred pathway to di-Z-isomers.

PubMed

Honda, Masaki; Kudo, Tatsuya; Kuwa, Takahiro; Higashiura, Takuma; Fukaya, Tetsuya; Inoue, Yoshinori; Kitamura, Chitoshi; Takehara, Munenori

2017-02-01

Lycopene has a large number of geometric isomers caused by E/Z isomerization at arbitrary sites within the 11 conjugated double bonds, offering varying characteristics related to features such as antioxidant capacity and bioavailability. However, the geometric structures of only a few lycopene Z-isomers have been thoroughly identified from natural sources. In this study, seven multi-Z-isomers of lycopene, (9Z,13'Z)-, (5Z,13Z,9'Z)-, (9Z,9'Z)-, (5Z,13'Z)-, (5Z,9'Z)-, (5Z,9Z,5'Z)-, and (5Z,9Z)-lycopene, were obtained from tomato samples by thermal isomerization, and then isolated by elaborate chromatography, and fully assigned using proton nuclear magnetic resonance. Moreover, the theoretically preferred pathway from (all-E)-lycopene to di-Z-isomers was examined with a computational approach using a Gaussian program. Fine-tuning of the HPLC separation conditions led to the discovery of novel multi-Z-isomers, and whose formation was supported by advanced theoretical calculations.

Tools for the microbiome. Nano and beyond

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

Biteen, Julie S.; Blainey, Paul C.; Cardon, Zoe G.

Here, the microbiome presents great opportunities for understanding and improving the world around us and elucidating the interactions that compose it. The microbiome also poses tremendous challenges for mapping and manipulating the entangled networks of interactions among myriad diverse organisms. Here, we describe the opportunities, technical needs, and potential approaches to address these challenges, based on recent and upcoming advances in measurement and control at the nanoscale and beyond. Moreover, these technical needs will provide the basis for advancing the largely descriptive studies of the microbiome to the theoretical and mechanistic understandings that will underpin the discipline of microbiome engineering.more » We anticipate that the new tools and methods developed will also be more broadly useful in environmental monitoring, medicine, forensics, and other areas.« less

An Assessment of the Residual Stresses in Low Pressure Plasma Sprayed Coatings on an Advanced Copper Alloy

NASA Technical Reports Server (NTRS)

Raj, S. V.; Ghosn, L. J.; Agarwal, A.; Lachtrupp, T. P.

2002-01-01

Modeling studies were conducted on low pressure plasma sprayed (LPPS) NiAl top coat applied to an advanced Cu-8(at.%)Cr-4%Nb alloy (GRCop-84) substrate using Ni as a bond coat. A thermal analysis suggested that the NiAl and Ni top and bond coats, respectively, would provide adequate thermal protection to the GRCop-84 substrate in a rocket engine operating under high heat flux conditions. Residual stress measurements were conducted at different depths from the free surface on coated and uncoated GRCop-84 specimens by x-ray diffraction. These data are compared with theoretically estimated values assessed by a finite element analysis simulating the development of these stresses as the coated substrate cools down from the plasma spraying temperature to room temperature.

Tools for the microbiome. Nano and beyond

DOE PAGES

Biteen, Julie S.; Blainey, Paul C.; Cardon, Zoe G.; ...

2015-12-22

Here, the microbiome presents great opportunities for understanding and improving the world around us and elucidating the interactions that compose it. The microbiome also poses tremendous challenges for mapping and manipulating the entangled networks of interactions among myriad diverse organisms. Here, we describe the opportunities, technical needs, and potential approaches to address these challenges, based on recent and upcoming advances in measurement and control at the nanoscale and beyond. Moreover, these technical needs will provide the basis for advancing the largely descriptive studies of the microbiome to the theoretical and mechanistic understandings that will underpin the discipline of microbiome engineering.more » We anticipate that the new tools and methods developed will also be more broadly useful in environmental monitoring, medicine, forensics, and other areas.« less

Investigation of Metal Oxide/Carbon Nano Material as Anode for High Capacity Lithium-ion Cells

NASA Technical Reports Server (NTRS)

Wu, James Jianjun; Hong, Haiping

2014-01-01

NASA is developing high specific energy and high specific capacity lithium-ion battery (LIB) technology for future NASA missions. Current state-of-art LIBs have issues in terms of safety and thermal stability, and are reaching limits in specific energy capability based on the electrochemical materials selected. For example, the graphite anode has a limited capability to store Li since the theoretical capacity of graphite is 372 mAh/g. To achieve higher specific capacity and energy density, and to improve safety for current LIBs, alternative advanced anode, cathode, and electrolyte materials are pursued under the NASA Advanced Space Power System Project. In this study, the nanostructed metal oxide, such as Fe2O3 on carbon nanotubes (CNT) composite as an LIB anode has been investigated.

Capturing Crime: The Qualitative Analysis of Individual Cases for Advancing Criminological Knowledge.

PubMed

Wright, Kevin A; Bouffard, Leana A

2016-02-01

The qualitative analysis of individual cases has a prominent place in the development of criminological theory, yet progression in the scientific study of crime has largely been viewed as a distinctly quantitative endeavor. In the process, much of the theoretical depth and precision supplied by earlier methods of criminological knowledge production have been sacrificed. The current work argues for a return to our criminological roots by supplementing quantitative analyses with the qualitative inspection of individual cases. We provide a specific example of a literature (i.e., criminal specialization/versatility) that has become increasingly quantitative and could benefit from the use of the proposed approach. We conclude by offering additional areas of research that might be advanced by our framework presented here. © The Author(s) 2014.

Biaxial experiments supporting the development of constitutive theories for advanced high-temperature materials

NASA Technical Reports Server (NTRS)

Ellis, J. R.

1988-01-01

Complex states of stress and strain are introduced into components during service in engineering applications. It follows that analysis of such components requires material descriptions, or constitutive theories, which reflect the tensorial nature of stress and strain. For applications involving stress levels above yield, the situation is more complex in that material response is both nonlinear and history dependent. This has led to the development of viscoplastic constitutive theories which introduce time by expressing the flow and evolutionary equation in the form of time derivatives. Models were developed here which can be used to analyze high temperature components manufactured from advanced composite materials. In parallel with these studies, effort was directed at developing multiaxial testing techniques to verify the various theories. Recent progress in the development of constitutive theories from both the theoretical and experimental viewpoints are outlined. One important aspect is that material descriptions for advanced composite materials which can be implemented in general purpose finite element codes and used for practical design are verified.

Assessment and Evaluation.

ERIC Educational Resources Information Center

Bachman, Lyle F.

1989-01-01

Applied linguistics and psychometrics have influenced language testing, providing additional tools for investigating factors affecting language test performance and assuring measurement reliability. An examination is presented of language testing, including the theoretical issues involved, the methodological advances, language test development,…

Atmospheric turbulence compensation in orbital angular momentum communications: Advances and perspectives

NASA Astrophysics Data System (ADS)

Li, Shuhui; Chen, Shi; Gao, Chunqing; Willner, Alan E.; Wang, Jian

2018-02-01

Orbital angular momentum (OAM)-carrying beams have recently generated considerable interest due to their potential use in communication systems to increase transmission capacity and spectral efficiency. For OAM-based free-space optical (FSO) links, a critical challenge is the atmospheric turbulence that will distort the helical wavefronts of OAM beams leading to the decrease of received power, introducing crosstalk between multiple channels, and impairing link performance. In this paper, we review recent advances in turbulence effects compensation techniques for OAM-based FSO communication links. First, basic concepts of atmospheric turbulence and theoretical model are introduced. Second, atmospheric turbulence effects on OAM beams are theoretically and experimentally investigated and discussed. Then, several typical turbulence compensation approaches, including both adaptive optics-based (optical domain) and signal processing-based (electrical domain) techniques, are presented. Finally, key challenges and perspectives of compensation of turbulence-distorted OAM links are discussed.

Specification and misspecification of theoretical foundations and logic models for health communication campaigns.

PubMed

Slater, Michael D

2006-01-01

While increasingly widespread use of behavior change theory is an advance for communication campaigns and their evaluation, such theories provide a necessary but not sufficient condition for theory-based communication interventions. Such interventions and their evaluations need to incorporate theoretical thinking about plausible mechanisms of message effect on health-related attitudes and behavior. Otherwise, strategic errors in message design and dissemination, and misspecified campaign logic models, insensitive to campaign effects, are likely to result. Implications of the elaboration likelihood model, attitude accessibility, attitude to the ad theory, exemplification, and framing are explored, and implications for campaign strategy and evaluation designs are briefly discussed. Initial propositions are advanced regarding a theory of campaign affect generalization derived from attitude to ad theory, and regarding a theory of reframing targeted health behaviors in those difficult contexts in which intended audiences are resistant to the advocated behavior or message.

Open source tools for the information theoretic analysis of neural data.

PubMed

Ince, Robin A A; Mazzoni, Alberto; Petersen, Rasmus S; Panzeri, Stefano

2010-01-01

The recent and rapid development of open source software tools for the analysis of neurophysiological datasets consisting of simultaneous multiple recordings of spikes, field potentials and other neural signals holds the promise for a significant advance in the standardization, transparency, quality, reproducibility and variety of techniques used to analyze neurophysiological data and for the integration of information obtained at different spatial and temporal scales. In this review we focus on recent advances in open source toolboxes for the information theoretic analysis of neural responses. We also present examples of their use to investigate the role of spike timing precision, correlations across neurons, and field potential fluctuations in the encoding of sensory information. These information toolboxes, available both in MATLAB and Python programming environments, hold the potential to enlarge the domain of application of information theory to neuroscience and to lead to new discoveries about how neurons encode and transmit information.

Some Aspects of Advanced Tokamak Modeling in DIII-D

NASA Astrophysics Data System (ADS)

St John, H. E.; Petty, C. C.; Murakami, M.; Kinsey, J. E.

2000-10-01

We extend previous work(M. Murakami, et al., General Atomics Report GA-A23310 (1999).) done on time dependent DIII-D advanced tokamak simulations by introducing theoretical confinement models rather than relying on power balance derived transport coefficients. We explore using NBCD and off axis ECCD together with a self-consistent aligned bootstrap current, driven by the internal transport barrier dynamics generated with the GLF23 confinement model, to shape the hollow current profile and to maintain MHD stable conditions. Our theoretical modeling approach uses measured DIII-D initial conditions to start off the simulations in a smooth consistent manner. This mitigates the troublesome long lived perturbations in the ohmic current profile that is normally caused by inconsistent initial data. To achieve this goal our simulation uses a sequence of time dependent eqdsks generated autonomously by the EFIT MHD equilibrium code in analyzing experimental data to supply the history for the simulation.

Research and development program for the development of advanced time-temperature dependent constitutive relationships. Volume 1: Theoretical discussion

NASA Technical Reports Server (NTRS)

Cassenti, B. N.

1983-01-01

The results of a 10-month research and development program for the development of advanced time-temperature constitutive relationships are presented. The program included (1) the effect of rate of change of temperature, (2) the development of a term to include time independent effects, and (3) improvements in computational efficiency. It was shown that rate of change of temperature could have a substantial effect on the predicted material response. A modification to include time-independent effects, applicable to many viscoplastic constitutive theories, was shown to reduce to classical plasticity. The computation time can be reduced by a factor of two if self-adaptive integration is used when compared to an integration using ordinary forward differences. During the course of the investigation, it was demonstrated that the most important single factor affecting the theoretical accuracy was the choice of material parameters.

Advanced optical fiber communication systems

NASA Astrophysics Data System (ADS)

Kazovsky, Leonid G.

1994-03-01

Our research is focused on three major aspects of advanced optical fiber communication systems: dynamic wavelength division multiplexing (WDM) networks, fiber nonlinearities, and high dynamic range coherent analog optical links. In the area of WDM networks, we have designed and implemented two high-speed interface boards and measured their throughput and latency. Furthermore, we designed and constructed an experimental PSK/ASK transceiver that simultaneously transmits packet-switched ASK data and circuit-switched PSK data on the same optical carrier. In the area of fiber nonlinearities, we investigated the theoretical impact of modulation frequency on cross-phase modulation (XPM) in dispersive fibers. In the area of high dynamic range coherent analog optical links, we developed theoretical expressions for the RF power transfer ratio (or RF power gain) and the noise figure (NF) of angle-modulated links. We then compared the RF power gains and noise figures of these links to that of an intensity modulated direct detection (DD) link.

Incorporating the soil environment and microbial community into plant competition theory

PubMed Central

Ke, Po-Ju; Miki, Takeshi

2015-01-01

Plants affect microbial communities and abiotic properties of nearby soils, which in turn influence plant growth and interspecific interaction, forming a plant-soil feedback (PSF). PSF is a key determinant influencing plant population dynamics, community structure, and ecosystem functions. Despite accumulating evidence for the importance of PSF and development of specific PSF models, different models are not yet fully integrated. Here, we review the theoretical progress in understanding PSF. When first proposed, PSF was integrated with various mathematical frameworks to discuss its influence on plant competition. Recent theoretical models have advanced PSF research at different levels of ecological organizations by considering multiple species, applying spatially explicit simulations to examine how local-scale predictions apply to larger scales, and assessing the effect of PSF on plant temporal dynamics over the course of succession. We then review two foundational models for microbial- and litter-mediated PSF. We present a theoretical framework to illustrate that although the two models are typically presented separately, their behavior can be understood together by invasibility analysis. We conclude with suggestions for future directions in PSF theoretical studies, which include specifically addressing microbial diversity to integrate litter- and microbial-mediated PSF, and apply PSF to general coexistence theory through a trait-based approach. PMID:26500621

Recent advances of nanotechnology in medicine and engineering

NASA Astrophysics Data System (ADS)

Nobile, Lucio; Nobile, Stefano

2016-05-01

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

Advanced aerodynamics. Selected NASA research

NASA Technical Reports Server (NTRS)

1981-01-01

This Conference Publication contains selected NASA papers that were presented at the Fifth Annual Status Review of the NASA Aircraft Energy Efficiency (ACEE) Energy Efficient Transport (EET) Program held at Dryden Flight Research Center in Edwards, California on September 14 to 15, 1981. These papers describe the status of several NASA in-house research activities in the areas of advanced turboprops, natural laminar flow, oscillating control surfaces, high-Reynolds-number airfoil tests, high-lift technology, and theoretical design techniques.

Recent advances of nanotechnology in medicine and engineering

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

Nobile, Lucio; Nobile, Stefano

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

Demographic faultlines: a meta-analysis of the literature.

PubMed

Thatcher, Sherry M B; Patel, Pankaj C

2011-11-01

We propose and test a theoretical model focusing on antecedents and consequences of demographic faultlines. We also posit contingencies that affect overall team dynamics in the context of demographic faultlines, such as the study setting and performance measurement. Using meta-analysis structural equation modeling with a final data set consisting of 311 data points (i.e., k [predictor-criterion relationships]), from 39 studies that were obtained from 36 papers with a total sample size of 24,388 individuals in 4,366 teams, we found that sex and racial diversity increased demographic faultline strength more than did diversity on the attributes of functional background, educational background, age, and tenure. Demographic faultline strength was found to increase task and relationship conflict as well as decrease team cohesion. Furthermore, although demographic faultline strength decreased both team satisfaction and team performance, there was a stronger decrease in team performance than in team satisfaction. The strength of these relationships increased when the study was conducted in the lab rather than in the field. We describe the theoretical and practical implications of these findings for advancing the study of faultlines. (c) 2011 APA, all rights reserved.

Integrating transition theory and bioecological theory: a theoretical perspective for nurses supporting the transition to adulthood for young people with medical complexity.

PubMed

Joly, Elizabeth

2016-06-01

To present a discussion of a theoretical perspective developed through integrating Meleis' Transition Theory and Bronfenbrenner's Bioecological Theory of Human Development to inform nursing and advanced nursing practice supporting the transition to adulthood for young people with medical complexity. Theoretical perspectives to inform nursing practice in supporting successful transition are limited, yet nurses frequently encounter young people with medical complexity during the transition to adulthood. Discussion paper. A literature search of CINAHL and Medline was conducted in 2014 and included articles from 2003-2014; informal discussions with families; the author's experiences in a transition program. The integrated theoretical perspective described in this paper can inform nurses and advanced practice nurses on contextual influences, program and intervention development across spheres of influence and outcomes for the transition to adulthood for young people with medical complexity. Young people and their families require effective reciprocal interactions with individuals and services across sectors to successfully transition to adulthood and become situated in the adult world. Intervention must also extend beyond the young person to include providers, services and health and social policy. Nurses can take a leadership role in supporting the transition to adulthood for young people with medical complexity through direct care, case management, education and research. It is integral that nurses holistically consider developmental processes, complexity and contextual conditions that promote positive outcomes during and beyond the transition to adulthood. © 2016 John Wiley & Sons Ltd.

How can a competency framework for advanced practice support care?

PubMed

Stanford, Pamela Elizabeth

2016-11-10

Aim To explore whether perception of nurse practitioners in relation to whether a competency framework for advanced practice can support their work. Method A qualitative cross-sectional design was used, embedded in an interpretative paradigm of research. A non-probability sample of eight experienced nurse practitioners took part in focus groups and answered questionnaires. A mixture of phenomenological and grounded theory approaches were used to collect the data. Findings Four major themes were identified: competency frameworks can identify individual strengths and weaknesses, they can be used to set clear goals and targets, they can improve how practice is organised, and they have the potential to limit practice in terms of narrowing boundaries. The study also found competency frameworks could provide an structure to guide the development and evaluation of educational programmes. Conclusion Competency frameworks can be used so to target the development of new advanced nurse practitioners. They can address workforce development and governance by ensuring nurse practitioners have the competencies to provide safe, autonomous practice. Competency frameworks have been shown to ensure consistency in clinical practice skills underpinned with nurse practitioners' theoretical knowledge. They provide a clear development structure for career development and advanced practice. However, internationally, there is still a lack of definition of advanced practice and its core competencies.

Nondestructive Evaluation of Adhesive Bonds via Ultrasonic Phase Measurements

NASA Technical Reports Server (NTRS)

Haldren, Harold A.; Perey, Daniel F.; Yost, William T.; Cramer, K. Elliott; Gupta, Mool C.

2016-01-01

The use of advanced composites utilizing adhesively bonded structures offers advantages in weight and cost for both the aerospace and automotive industries. Conventional nondestructive evaluation (NDE) has proved unable to reliably detect weak bonds or bond deterioration during service life conditions. A new nondestructive technique for quantitatively measuring adhesive bond strength is demonstrated. In this paper, an ultrasonic technique employing constant frequency pulsed phased-locked loop (CFPPLL) circuitry to monitor the phase response of a bonded structure from change in thermal stress is discussed. Theoretical research suggests that the thermal response of a bonded interface relates well with the quality of the adhesive bond. In particular, the effective stiffness of the adhesive-adherent interface may be extracted from the thermal phase response of the structure. The sensitivity of the CFPPLL instrument allows detection of bond pathologies that have been previously difficult-to-detect. Theoretical results with this ultrasonic technique on single epoxy lap joint (SLJ) specimens are presented and discussed. This technique has the potential to advance the use of adhesive bonds - and by association, advanced composite structures - by providing a reliable method to measure adhesive bond strength, thus permitting more complex, lightweight, and safe designs.

Data Curation and Visualization for MuSIASEM Analysis of the Nexus

NASA Astrophysics Data System (ADS)

Renner, Ansel

2017-04-01

A novel software-based approach to relational analysis applying recent theoretical advancements of the Multi-Scale Integrated Analysis of Societal and Ecosystem Metabolism (MuSIASEM) accounting framework is presented. This research explores and explains underutilized ways software can assist complex system analysis across the stages of data collection, exploration, analysis and dissemination and in a transparent and collaborative manner. This work is being conducted as part of, and in support of, the four-year European Commission H2020 project: Moving Towards Adaptive Governance in Complexity: Informing Nexus Security (MAGIC). In MAGIC, theoretical advancements to MuSIASEM propose a powerful new approach to spatial-temporal WEFC relational analysis in accordance with a structural-functional scaling mechanism appropriate for biophysically relevant complex system analyses. Software is designed primarily with JavaScript using the Angular2 model-view-controller framework and the Data-Driven Documents (D3) library. These design choices clarify and modularize data flow, simplify research practitioner's work, allow for and assist stakeholder involvement and advance collaboration at all stages. Data requirements and scalable, robust yet light-weight structuring will first be explained. Following, algorithms to process this data will be explored. Data interfaces and data visualization approaches will lastly be presented and described.

The Complexity of Primary Care Psychology: Theoretical Foundations.

PubMed

Smit, E H; Derksen, J J L

2015-07-01

How does primary care psychology deal with organized complexity? Has it escaped Newtonian science? Has it, as Weaver (1991) suggests, found a way to 'manage problems with many interrelated factors that cannot be dealt by statistical techniques'? Computer simulations and mathematical models in psychology are ongoing positive developments in the study of complex systems. However, the theoretical development of complex systems in psychology lags behind these advances. In this article we use complexity science to develop a theory on experienced complexity in the daily practice of primary care psychologists. We briefly answer the ontological question of what we see (from the perspective of primary care psychology) as reality, the epistemological question of what we can know, the methodological question of how to act, and the ethical question of what is good care. Following our empirical study, we conclude that complexity science can describe the experienced complexity of the psychologist and offer room for personalized client-centered care. Complexity science is slowly filling the gap between the dominant reductionist theory and complex daily practice.

Empiric validation of a process for behavior change.

PubMed

Elliot, Diane L; Goldberg, Linn; MacKinnon, David P; Ranby, Krista W; Kuehl, Kerry S; Moe, Esther L

2016-09-01

Most behavior change trials focus on outcomes rather than deconstructing how those outcomes related to programmatic theoretical underpinnings and intervention components. In this report, the process of change is compared for three evidence-based programs' that shared theories, intervention elements and potential mediating variables. Each investigation was a randomized trial that assessed pre- and post- intervention variables using survey constructs with established reliability. Each also used mediation analyses to define relationships. The findings were combined using a pattern matching approach. Surprisingly, knowledge was a significant mediator in each program (a and b path effects [p<0.01]). Norms, perceived control abilities, and self-monitoring were confirmed in at least two studies (p<0.01 for each). Replication of findings across studies with a common design but varied populations provides a robust validation of the theory and processes of an effective intervention. Combined findings also demonstrate a means to substantiate process aspects and theoretical models to advance understanding of behavior change.

Cyberframing Cancer: An Exploratory Investigation of Valenced Cybercoping on Cancer Blogs.

PubMed

Donovan, Erin E; Nelson, Erin C; Scheinfeld, Emily

2017-01-01

Although scholarship on coping with cancer implies many ways that coping is communicative, the discursive features of coping have been understudied. The purpose of the present investigation was to theorize the content of cancer blogs, a form of cybercoping, by examining valenced coping-relevant frames that bloggers use to describe their experiences with cancer. This research is both theoretically and methodologically innovative. Theoretically, we advance the concept of cyberframing by connecting the rather disconnected literatures on coping and framing and by studying this topic from a communication perspective. Methodologically, this is one of the few studies of coping with cancer that has used naturally occurring communication data to its advantage. A content analysis of cancer blog entries (N = 194) indicated that more than 90% of cancer blog posts were embedded in a valenced frame. The frames were either negative, positive, or balanced; balanced frames varied in the intensity of the valence. The most common frames were positive and balanced with low affect.

Traveling waves in actin dynamics and cell motility

PubMed Central

Allard, Jun; Mogilner, Alex

2012-01-01

Much of current understanding of cell motility arose from studying steady treadmilling of actin arrays. Recently, there have been a growing number of observations of a more complex, non-steady, actin behavior, including self-organized waves. It is becoming clear that these waves result from activation and inhibition feedbacks in actin dynamics acting on different scales, but the exact molecular nature of these feedbacks and respective roles of biomechanics and biochemistry are still unclear. Here, we review recent advances achieved in experimental and theoretical studies of actin waves and discuss mechanisms and physiological significance of wavy protrusions. PMID:22985541

Exploration of the Theoretical Physical Capacity of the John F. Kennedy International Airport Runway System

NASA Technical Reports Server (NTRS)

Neitzke, Kurt W.; Guerreiro, Nelson M.

2014-01-01

A design study was completed to explore the theoretical physical capacity (TPC) of the John F. Kennedy International Airport (KJFK) runway system for a northflow configuration assuming impedance-free (to throughput) air traffic control functionality. Individual runways were modeled using an agent-based, airspace simulation tool, the Airspace Concept Evaluation System (ACES), with all runways conducting both departures and arrivals on a first-come first-served (FCFS) scheduling basis. A realistic future flight schedule was expanded to 3.5 times the traffic level of a selected baseline day, September 26, 2006, to provide a steady overdemand state for KJFK runways. Rules constraining departure and arrival operations were defined to reflect physical limits beyond which safe operations could no longer be assumed. Safety buffers to account for all sources of operational variability were not included in the TPC estimate. Visual approaches were assumed for all arrivals to minimize inter-arrival spacing. Parallel runway operations were assumed to be independent based on lateral spacing distances. Resulting time intervals between successive airport operations were primarily constrained by same-runway and then by intersecting-runway spacing requirements. The resulting physical runway capacity approximates a theoretical limit that cannot be exceeded without modifying runway interaction assumptions. Comparison with current KJFK operational limits for a north-flow runway configuration indicates a substantial throughput gap of approximately 48%. This gap may be further analyzed to determine which part may be feasibly bridged through the deployment of advanced systems and procedures, and which part cannot, because it is either impossible or not cost-effective to control. Advanced systems for bridging the throughput gap may be conceptualized and simulated using this same experimental setup to estimate the level of gap closure achieved.

From theory to 'measurement' in complex interventions: methodological lessons from the development of an e-health normalisation instrument.

PubMed

Finch, Tracy L; Mair, Frances S; O'Donnell, Catherine; Murray, Elizabeth; May, Carl R

2012-05-17

Although empirical and theoretical understanding of processes of implementation in health care is advancing, translation of theory into structured measures that capture the complex interplay between interventions, individuals and context remain limited. This paper aimed to (1) describe the process and outcome of a project to develop a theory-based instrument for measuring implementation processes relating to e-health interventions; and (2) identify key issues and methodological challenges for advancing work in this field. A 30-item instrument (Technology Adoption Readiness Scale (TARS)) for measuring normalisation processes in the context of e-health service interventions was developed on the basis on Normalization Process Theory (NPT). NPT focuses on how new practices become routinely embedded within social contexts. The instrument was pre-tested in two health care settings in which e-health (electronic facilitation of healthcare decision-making and practice) was used by health care professionals. The developed instrument was pre-tested in two professional samples (N=46; N=231). Ratings of items representing normalisation 'processes' were significantly related to staff members' perceptions of whether or not e-health had become 'routine'. Key methodological challenges are discussed in relation to: translating multi-component theoretical constructs into simple questions; developing and choosing appropriate outcome measures; conducting multiple-stakeholder assessments; instrument and question framing; and more general issues for instrument development in practice contexts. To develop theory-derived measures of implementation process for progressing research in this field, four key recommendations are made relating to (1) greater attention to underlying theoretical assumptions and extent of translation work required; (2) the need for appropriate but flexible approaches to outcomes measurement; (3) representation of multiple perspectives and collaborative nature of work; and (4) emphasis on generic measurement approaches that can be flexibly tailored to particular contexts of study.

Jet engine applications for materials with nanometer-scale dimensions

NASA Technical Reports Server (NTRS)

Appleby, J. W., Jr.

1995-01-01

The performance of advanced military and commercial gas turbine engines is often linked to advances in materials technology. High performance gas turbine engines being developed require major material advances in strength, toughness, reduced density and improved temperature capability. The emerging technology of nanostructured materials has enormous potential for producing materials with significant improvements in these properties. Extraordinary properties demonstrated in the laboratory include material strengths approaching theoretical limit, ceramics that demonstrate ductility and toughness, and materials with ultra-high hardness. Nanostructured materials and coatings have the potential for meeting future gas turbine engine requirements for improved performance, reduced weight and lower fuel consumption.

Jet engine applications for materials with nanometer-scale dimensions

NASA Technical Reports Server (NTRS)

Appleby, J. W., Jr.

1995-01-01

The performance of advanced military and commercial gas turbine engines is often linked to advances in materials technology. High performance gas turbine engines being developed require major material advances in strength, toughness, reduced density and improved temperature capability. The emerging technology of nanostructured materials has enormous potential for producing materials with significant improvements in these properties. Extraordinary properties demonstrated in the laboratory include material strengths approaching theoretical limit, ceramics that demonstrate ductility and toughness, and material with ultra-high hardness. Nanostructured materials and coatings have the potential for meeting future gas turbine engine requirements for improved performance, reduced weight and lower fuel consumption.

Analytical modeling and feasibility study of a multi-GPU cloud-based server (MGCS) framework for non-voxel-based dose calculations.

PubMed

Neylon, J; Min, Y; Kupelian, P; Low, D A; Santhanam, A

2017-04-01

In this paper, a multi-GPU cloud-based server (MGCS) framework is presented for dose calculations, exploring the feasibility of remote computing power for parallelization and acceleration of computationally and time intensive radiotherapy tasks in moving toward online adaptive therapies. An analytical model was developed to estimate theoretical MGCS performance acceleration and intelligently determine workload distribution. Numerical studies were performed with a computing setup of 14 GPUs distributed over 4 servers interconnected by a 1 Gigabits per second (Gbps) network. Inter-process communication methods were optimized to facilitate resource distribution and minimize data transfers over the server interconnect. The analytically predicted computation time predicted matched experimentally observations within 1-5 %. MGCS performance approached a theoretical limit of acceleration proportional to the number of GPUs utilized when computational tasks far outweighed memory operations. The MGCS implementation reproduced ground-truth dose computations with negligible differences, by distributing the work among several processes and implemented optimization strategies. The results showed that a cloud-based computation engine was a feasible solution for enabling clinics to make use of fast dose calculations for advanced treatment planning and adaptive radiotherapy. The cloud-based system was able to exceed the performance of a local machine even for optimized calculations, and provided significant acceleration for computationally intensive tasks. Such a framework can provide access to advanced technology and computational methods to many clinics, providing an avenue for standardization across institutions without the requirements of purchasing, maintaining, and continually updating hardware.

Aerothermodynamics research at NASA Ames Research Center

NASA Technical Reports Server (NTRS)

Deiwert, George S.

1987-01-01

Research activity in the aerothermodynamics branch at the NASA Ames Research Center is reviewed. Advanced concepts and mission studies relating to the next generation aerospace transportation systems are summarized and directions for continued research identified. Theoretical and computational studies directed at determining flow fields and radiative and convective heating loads in real gases are described. Included are Navier-Stokes codes for equilibrium and thermochemical nonequilibrium air. Experimental studies in the 3.5-ft hypersonic wind tunnel, the ballistic ranges, and the electric arc driven shock tube are described. Tested configurations include generic hypersonic aerospace plane configurations, aeroassisted orbital transfer vehicle shapes and Galileo probe models.

A study of hadronic decays of the chi(c) states produced in psi-prime radiative transitions at the Beijing Experimental Spectrometer

NASA Astrophysics Data System (ADS)

Varner, Gary Sim

1999-11-01

Utilizing the world's largest sample of resonant y' decays, as measured by the Beijing Experimental Spectrometer (BES) during 1993-1995, a comprehensive study of the hadronic decay modes of the χc (3P1 Charmonium) states has been undertaken. Compared with the data set for the Mark I detector, whose published measurements of many of these hadronic decays have been definitive for almost 20 years, roughly an order of magnitude larger statistics has been obtained. Taking advantage of these larger statistics, many new hadronic decay modes have been discovered, while others have been refined. An array of first observations, improvements, confirmations or limits are reported with respect to current world values. These higher precision and newly discovered decay modes are an excellent testing ground for recent theoretical interest in the contribution of higher Fock states and the color octet mechanism in heavy quarkonium annihilation and subsequent light hadronization. Because these calculations are largely tractable only in two body decays, these are the focus of this dissertation. A comparison of current theoretical calculations and experimental results is presented, indicating the success of these phenomenological advances. Measurements for which there are as yet no suitable theoretical prediction are indicated.

Bridging the engineering gap: integrated systems thinking

NASA Astrophysics Data System (ADS)

Weintré, J. R.; Delfi, M.

2017-09-01

On visits to rural Indonesia it is apparent that the advances made possible by technical engineered solutions, are rarely at the same pace as the human captivation of technical development. This uneven pace has limited the application of labour-saving equipment and efficiency. It is suggested to be of primary importance to advance technical application skills among communities as part of the continuous advancement cycle in our human environment. A creative approach to inclusive technology and internal transfer of equipment knowledge in society, reduces barriers and could diminish structural or societal undesired situations. Earlier theoretical concepts provide us a lens for describing the practices of habitus, conceptualization of social capital and integrated systems thinking. The interrelationship and complexities in technical and social systems requires to be investigated. This paper aims to describe those, combined with technological applications in an empirical ethnographic approach. The study analyses the negotiations of community members with the available technology. It intends to foster a better understanding of the various cultural-economic values by exploring the systems thinking theory, with a focus on rice cultivation in Indonesia, Japan and Australia. This research suggests that cultural, economic and technical advances vary considerably and human expectations are strongly influenced by local culture.

Siblings of Youth with Autism Spectrum Disorders: Theoretical Perspectives on Sibling Relationships and Individual Adjustment

PubMed Central

McHale, Susan M.; Updegraff, Kimberly A.; Feinberg, Mark E.

2015-01-01

A burgeoning research literature investigates the sibling relationships of youth with Autism Spectrum Disorder (ASD) and their implications for individual adjustment. Focusing on four relationship domains-- behaviors, emotions, cognitions and involvement—and toward advancing this generally atheoretical literature, we review and apply tenets from a range of theoretical perspectives in an effort to illuminate the mechanisms underlying sibling relationship experiences and their adjustment implications. Our review suggests new directions for research to test theoretically-grounded hypotheses about how sibling relationships develop and are linked to individual adjustment. In addition, we consider how identifying underlying bio-psycho-social processes can aid in the development of interventions to promote warm and involved sibling relationships and positive youth development. PMID:26476737

Theoretical and experimental investigation of optical absorption anisotropy in β-Ga2O3.

PubMed

Ricci, F; Boschi, F; Baraldi, A; Filippetti, A; Higashiwaki, M; Kuramata, A; Fiorentini, V; Fornari, R

2016-06-08

The question of optical bandgap anisotropy in the monoclinic semiconductor β-Ga2O3 was revisited by combining accurate optical absorption measurements with theoretical analysis, performed using different advanced computation methods. As expected, the bandgap edge of bulk β-Ga2O3 was found to be a function of light polarization and crystal orientation, with the lowest onset occurring at polarization in the ac crystal plane around 4.5-4.6 eV; polarization along b unambiguously shifts the onset up by 0.2 eV. The theoretical analysis clearly indicates that the shift in the b onset is due to a suppression of the transition matrix elements of the three top valence bands at Γ point.

Advancements in Theoretical Models of Confined Vortex Flowfields

DTIC Science & Technology

2007-03-29

blades, curved vanes, vortex generators, twisted tape inserts, triangular winglets , propellers, coiled wires, tangential injectors, and other...Corresponding boundary conditions consist of the no slip at the wall and blending with the composite inner solution in the outer domain. Following similar

Photoelectric Effect: Back to Basics.

ERIC Educational Resources Information Center

Powell, R. A.

1978-01-01

Presents a simplified theoretical analysis of the variation of quantum yield with photon energy in the photoelectric experiment. Describes a way to amplify the experiment and make it more instructive to advanced students through the measurement of quantum yield of a photo cell. (GA)

Advances in Experiment Design for High Performance Aircraft

NASA Technical Reports Server (NTRS)

Morelli, Engene A.

1998-01-01

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

Ultrasonic nondestructive evaluation, microstructure, and mechanical property interrelations

NASA Technical Reports Server (NTRS)

Vary, A.

1984-01-01

Ultrasonic techniques for mechanical property characterizations are reviewed and conceptual models are advanced for explaining and interpreting the empirically based results. At present, the technology is generally empirically based and is emerging from the research laboratory. Advancement of the technology will require establishment of theoretical foundations for the experimentally observed interrelations among ultrasonic measurements, mechanical properties, and microstructure. Conceptual models are applied to ultrasonic assessment of fracture toughness to illustrate an approach for predicting correlations found among ultrasonic measurements, microstructure, and mechanical properties.

The Intelligentsia and Social Movements

NASA Astrophysics Data System (ADS)

Bleimaier, John Kuhn

2015-03-01

The Intelligentsia is that social stratum comprised of individuals for whom intellectual activity is a passion. To a certain extent all human enterprise has an intellectual component, being based on mans sentient nature. In a technologically advanced society most employment requires advanced education and the application of complex reasoning to problem solving. However, the members of the Intelligentsia engage in analytical and creative thinking for its own sake. The Intelligentsia probes the theoretical underpinnings and seeks transcendent understanding. This entails attempting to discover fundamental principles...

Linear Scaling Density Functional Calculations with Gaussian Orbitals

NASA Technical Reports Server (NTRS)

Scuseria, Gustavo E.

1999-01-01

Recent advances in linear scaling algorithms that circumvent the computational bottlenecks of large-scale electronic structure simulations make it possible to carry out density functional calculations with Gaussian orbitals on molecules containing more than 1000 atoms and 15000 basis functions using current workstations and personal computers. This paper discusses the recent theoretical developments that have led to these advances and demonstrates in a series of benchmark calculations the present capabilities of state-of-the-art computational quantum chemistry programs for the prediction of molecular structure and properties.

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

Bader, S. D.; Materials Science Division

The collective creativity of those working in the field of surface magnetism has stimulated an impressive range of advances. Once wary, theorists are now eager to enter the field. The present article attempts to take a snapshot of where the field has been, with an eye to the more speculative issue of where it is going. Selective examples are used to highlight three general areas of interest (1) characterization techniques, (2) materials properties, and (3) theoretical/simulational advances. Emerging directions are identified and discussed, including laterally confined nanomagnetism and spintronics.

Advancement of proprotor technology. Task 2: Wind-tunnel test results

NASA Technical Reports Server (NTRS)

1971-01-01

An advanced-design 25-foot-diameter flightworthy proprotor was tested in the NASA-Ames Large-Scale Wind Tunnel. These tests, have verified and confirmed the theory and design solutions developed as part of the Army Composite Aircraft Program. This report presents the test results and compares them with theoretical predictions. During performance tests, the results met or exceeded predictions. Hover thrust 15 percent greater than the predicted maximum was measured. In airplane mode, propulsive efficiencies (some of which exceeded 90 percent) agreed with theory.

A theoretical study of the coupling between a vortex-induced vibration cylindrical resonator and an electromagnetic energy harvester

NASA Astrophysics Data System (ADS)

Xu-Xu, J.; Barrero-Gil, A.; Velazquez, A.

2015-11-01

This paper presents a theoretical study of the coupling between a vortex-induced vibration (VIV) cylindrical resonator and its associated linear electromagnetic generator. The two-equation mathematical model is based on a dual-mass formulation in which the dominant masses are the stator and translator masses of the generator. The fluid-structure interaction implemented in the model equations follows the so-called ‘advanced forcing model’ whose closure relies on experimental data. The rationale to carry out the study is the fact that in these types of configurations there is a two-way interaction between the moving parts in such a way that their motions influence each other simultaneously, thereby affecting the energy actually harvested. It is believed that instead of mainly resorting to complementary numerical simulations, a theoretical model can shed some light on the nature of the interaction and, at the same time, provide scaling laws that can be used for practical design and optimization purposes. It has been found that the proposed configuration has a maximum hydrodynamic to mechanical to electrical conversion efficiency (based on the VIV resonator oscillation amplitude) of 8%. For a cylindrical resonator 10 cm long with a 2 cm diameter, this translates into an output power of 20 to 160 mW for water stream velocities in the range from 0.5 to 1 m s-1.

Discovering chemistry with an ab initio nanoreactor

DOE PAGES

Wang, Lee-Ping; Titov, Alexey; McGibbon, Robert; ...

2014-11-02

Chemical understanding is driven by the experimental discovery of new compounds and reactivity, and is supported by theory and computation that provides detailed physical insight. While theoretical and computational studies have generally focused on specific processes or mechanistic hypotheses, recent methodological and computational advances harken the advent of their principal role in discovery. Here we report the development and application of the ab initio nanoreactor – a highly accelerated, first-principles molecular dynamics simulation of chemical reactions that discovers new molecules and mechanisms without preordained reaction coordinates or elementary steps. Using the nanoreactor we show new pathways for glycine synthesis frommore » primitive compounds proposed to exist on the early Earth, providing new insight into the classic Urey-Miller experiment. Ultimately, these results highlight the emergence of theoretical and computational chemistry as a tool for discovery in addition to its traditional role of interpreting experimental findings.« less

Discovering chemistry with an ab initio nanoreactor

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

Wang, Lee-Ping; Titov, Alexey; McGibbon, Robert

Chemical understanding is driven by the experimental discovery of new compounds and reactivity, and is supported by theory and computation that provides detailed physical insight. While theoretical and computational studies have generally focused on specific processes or mechanistic hypotheses, recent methodological and computational advances harken the advent of their principal role in discovery. Here we report the development and application of the ab initio nanoreactor – a highly accelerated, first-principles molecular dynamics simulation of chemical reactions that discovers new molecules and mechanisms without preordained reaction coordinates or elementary steps. Using the nanoreactor we show new pathways for glycine synthesis frommore » primitive compounds proposed to exist on the early Earth, providing new insight into the classic Urey-Miller experiment. Ultimately, these results highlight the emergence of theoretical and computational chemistry as a tool for discovery in addition to its traditional role of interpreting experimental findings.« less

Advanced ab initio relativistic calculations of transition probabilities for some O I and O III emission lines

NASA Astrophysics Data System (ADS)

Nguyen, T. V. B.; Chantler, C. T.; Lowe, J. A.; Grant, I. P.

2014-06-01

This work presents new ab initio relativistic calculations using the multiconfiguration Dirac-Hartree-Fock method of some O I and O III transition lines detected in B-type and Wolf-Rayet stars. Our results are the first able to be presented in both the length and velocity gauges, with excellent gauge convergence. Compared to previous experimental and theoretical uncertainties of up to 50 per cent, our accuracies appear to be in the range of 0.33-5.60 per cent, with gauge convergence up to 0.6 per cent. Similar impressive convergence of the calculated energies is also shown. Two sets of theoretical computations are compared with earlier tabulated measurements. Excellent agreement is obtained with one set of transitions but an interesting and consistent discrepancy exists between the current work and the prior literature, deserving of future experimental studies.

Interstellar Polycyclic Aromatic Compounds and Astrophysics

NASA Technical Reports Server (NTRS)

Hudgins, Douglas M.; DeVincenzi, Donald (Technical Monitor)

2001-01-01

Over the past fifteen years, thanks to significant, parallel advancements in observational, experimental, and theoretical techniques, tremendous strides have been made in our understanding of the role polycyclic aromatic compounds (PAC) in the interstellar medium (ISM). Twenty years ago, the notion of an abundant population of large, carbon rich molecules in the ISM was considered preposterous. Today, the unmistakable spectroscopic signatures of PAC - shockingly large molecules by previous interstellar chemistry standards - are recognized throughout the Universe. In this paper, we will examine the interstellar PAC model and its importance to astrophysics, including: (1) the evidence which led to inception of the model; (2) the ensuing laboratory and theoretical studies of the fundamental spectroscopic properties of PAC by which the model has been refined and extended; and (3) a few examples of how the model is being exploited to derive insight into the nature of the interstellar PAC population.

Numerical detection of the Gardner transition in a mean-field glass former.

PubMed

Charbonneau, Patrick; Jin, Yuliang; Parisi, Giorgio; Rainone, Corrado; Seoane, Beatriz; Zamponi, Francesco

2015-07-01

Recent theoretical advances predict the existence, deep into the glass phase, of a novel phase transition, the so-called Gardner transition. This transition is associated with the emergence of a complex free energy landscape composed of many marginally stable sub-basins within a glass metabasin. In this study, we explore several methods to detect numerically the Gardner transition in a simple structural glass former, the infinite-range Mari-Kurchan model. The transition point is robustly located from three independent approaches: (i) the divergence of the characteristic relaxation time, (ii) the divergence of the caging susceptibility, and (iii) the abnormal tail in the probability distribution function of cage order parameters. We show that the numerical results are fully consistent with the theoretical expectation. The methods we propose may also be generalized to more realistic numerical models as well as to experimental systems.

Short Review on Quantum Key Distribution Protocols.

PubMed

Giampouris, Dimitris

2017-01-01

Cryptographic protocols and mechanisms are widely investigated under the notion of quantum computing. Quantum cryptography offers particular advantages over classical ones, whereas in some cases established protocols have to be revisited in order to maintain their functionality. The purpose of this paper is to provide the basic definitions and review the most important theoretical advancements concerning the BB84 and E91 protocols. It also aims to offer a summary on some key developments on the field of quantum key distribution, closely related with the two aforementioned protocols. The main goal of this study is to provide the necessary background information along with a thorough review on the theoretical aspects of QKD, concentrating on specific protocols. The BB84 and E91 protocols have been chosen because most other protocols are similar to these, a fact that makes them important for the general understanding of how the QKD mechanism functions.

The Impact of Solid Surface Features on Fluid-Fluid Interface Configuration

NASA Astrophysics Data System (ADS)

Araujo, J. B.; Brusseau, M. L. L.

2017-12-01

Pore-scale fluid processes in geological media are critical for a broad range of applications such as radioactive waste disposal, carbon sequestration, soil moisture distribution, subsurface pollution, land stability, and oil and gas recovery. The continued improvement of high-resolution image acquisition and processing have provided a means to test the usefulness of theoretical models developed to simulate pore-scale fluid processes, through the direct quantification of interfaces. High-resolution synchrotron X-ray microtomography is used in combination with advanced visualization tools to characterize fluid distributions in natural geologic media. The studies revealed the presence of fluid-fluid interface associated with macroscopic features on the surfaces of the solids such as pits and crevices. These features and respective fluid interfaces, which are not included in current theoretical or computational models, may have a significant impact on accurate simulation and understanding of multi-phase flow, energy, heat and mass transfer processes.

A comparison of theoretical and experimental pressure distributions for two advanced fighter wings

NASA Technical Reports Server (NTRS)

Haney, H. P.; Hicks, R. M.

1981-01-01

A comparison was made between experimental pressure distributions measured during testing of the Vought A-7 fighter and the theoretical predictions of four transonic potential flow codes. Isolated wind and three wing-body codes were used for comparison. All comparisons are for transonic Mach numbers and include both attached and separate flows. In general, the wing-body codes gave better agreement with the experiment than did the isolated wing code but, because of the greater complexity of the geometry, were found to be considerably more expensive and less reliable.

Minimum emittance in TBA and MBA lattices

NASA Astrophysics Data System (ADS)

Xu, Gang; Peng, Yue-Mei

2015-03-01

For reaching a small emittance in a modern light source, triple bend achromats (TBA), theoretical minimum emittance (TME) and even multiple bend achromats (MBA) have been considered. This paper derived the necessary condition for achieving minimum emittance in TBA and MBA theoretically, where the bending angle of inner dipoles has a factor of 31/3 bigger than that of the outer dipoles. Here, we also calculated the conditions attaining the minimum emittance of TBA related to phase advance in some special cases with a pure mathematics method. These results may give some directions on lattice design.

Piezoelectric transformer structural modeling--a review.

PubMed

Yang, Jiashi

2007-06-01

A review on piezoelectric transformer structural modeling is presented. The operating principle and the basic behavior of piezoelectric transformers as governed by the linear theory of piezoelectricity are shown by a simple, theoretical analysis on a Rosen transformer based on extensional modes of a nonhomogeneous ceramic rod. Various transformers are classified according to their structural shapes, operating modes, and voltage transforming capability. Theoretical and numerical modeling results from the theory of piezoelectricity are reviewed. More advances modeling on thermal and nonlinear effects also are discussed. The article contains 167 references.

[Educative intervention and development of position and critical reading].

PubMed

Angulo-Bernal, Sonia Elizabeth; Leyva-González, Félix Arturo; Viniegra-Velázquez, Leonardo

2007-01-01

To investigate the professors of technical courses of the area of health, the effects of a promotional educative strategy of the participation in the development of a position prior to the education and of the aptitude for the critical theoretical text reading and information of educative research. A longitudinal study took place, of intervention. In order to measure the degree of development of a position before the education, it was applied to the instrument Concepts and ideas about education. It consists of 72 statements, organized in duple that expresses two different approaches from education: participative and passive. For the inquiry of the degree of development of critical reading two instruments were applied: 1) Theoretical text reading of education and, 2) Reading information of educative research, constituted both by 120 itemes. The validity and trustworthiness of the three instruments were valued by experts with experience in teaching and educative research. The strategy was implemented through activities in seminary form, which were done twice a week, with a duration of five hours per session, for nine months; within the activities outside the classroom, the student completed reading of a theoretical text and/or report of educative research and the resolution of a reading guide (task). During the activities in a propitious classroom, discussion atmosphere and promoting at any moment the participation of the students; a space for the reflective recovery of their own experience was opened, for the analysis and interchange of ideas and for the critic and self-criticism of the main educative practices. The professor intervened when individual participation diminished; he also channeled the discussion, indicating to the enlightening observations and strong arguments of the students. The three instruments were applied to the group of professors of technical courses (n = 10); the initial measurement was applied before initiating the educative strategy and the final measurement at the end of the same plan. The qualification of the instruments and the capture of information were made by a blind technical worker. Subsequent to the educative strategy we observed a statistically significant advance in position -inferred through its main indicator: critical theoretical text consequence- and reading. The advances shown in critical reading for information of educative research were below the critical theoretical text reading. The development of position before the education and the aptitudes for critical reading of theoretical texts and information of educative research, in professors of technical courses of the area of health, it is possible, if educative atmospheres are created that lead to the participation -halfway through by the critic.

Measuring binding kinetics of aromatic thiolated molecules with nanoparticles via surface-enhanced Raman spectroscopy

NASA Astrophysics Data System (ADS)

Devetter, Brent M.; Mukherjee, Prabuddha; Murphy, Catherine J.; Bhargava, Rohit

2015-05-01

Colloidal plasmonic nanomaterials, consisting of metals such as gold and silver, are excellent candidates for advanced optical probes and devices, but precise control over surface chemistry is essential for realizing their full potential. Coupling thiolated (R-SH) molecules to nanoprobe surfaces is a convenient and established route to tailor surface properties. The ability to dynamically probe and monitor the surface chemistry of nanoparticles in solution is essential for rapidly manufacturing spectroscopically tunable nanoparticles. In this study, we report the development of surface-enhanced Raman spectroscopy (SERS) as a method to monitor the kinetics of gold-thiolate bond formation on colloidal gold nanoparticles. A theoretical model combining SERS enhancement with the Beer-Lambert law is proposed to explain ensemble scattering and absorption effects in colloids during chemisorption. In order to maximize biological relevance and signal reproducibility, experiments used to validate the model focused on maintaining nanoparticle stability after the addition of water-soluble aromatic thiolated molecules. Our results indicate that ligand exchange on gold nanoparticles follow a first-order Langmuir adsorption model with rate constants on the order of 0.01 min-1. This study demonstrates an experimental spectroscopic method and theoretical model for monitoring binding kinetics that may prove useful for designing novel probes.Colloidal plasmonic nanomaterials, consisting of metals such as gold and silver, are excellent candidates for advanced optical probes and devices, but precise control over surface chemistry is essential for realizing their full potential. Coupling thiolated (R-SH) molecules to nanoprobe surfaces is a convenient and established route to tailor surface properties. The ability to dynamically probe and monitor the surface chemistry of nanoparticles in solution is essential for rapidly manufacturing spectroscopically tunable nanoparticles. In this study, we report the development of surface-enhanced Raman spectroscopy (SERS) as a method to monitor the kinetics of gold-thiolate bond formation on colloidal gold nanoparticles. A theoretical model combining SERS enhancement with the Beer-Lambert law is proposed to explain ensemble scattering and absorption effects in colloids during chemisorption. In order to maximize biological relevance and signal reproducibility, experiments used to validate the model focused on maintaining nanoparticle stability after the addition of water-soluble aromatic thiolated molecules. Our results indicate that ligand exchange on gold nanoparticles follow a first-order Langmuir adsorption model with rate constants on the order of 0.01 min-1. This study demonstrates an experimental spectroscopic method and theoretical model for monitoring binding kinetics that may prove useful for designing novel probes. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr01006c

Developing the role of Swedish advanced practice nurse (APN) through a blended learning master's program: Consequences of knowledge organisation.

PubMed

Bergström, Peter; Lindh, Viveca

2018-01-01

This paper reports on a research study conducted with a group of nurses in Sweden enrolled in a newly developed blended learning master's programme to become advanced practice nurses (APNs). As background, the paper presents the regional needs the programme is intended to address and describes how the programme was designed. The aim was to understand how, from students' perspective, the nurse master's programme structured knowledge for their future position as APNs. The research question focuses on how the master's programme prepares students by meeting their diverse needs for knowledge. Empirical material was collected at two times during the students' first and second years of study through semi-structured qualitative interviews. The findings highlight the process in which these master's students gained a more advanced identity of becoming APNs. This process demonstrates how students perceive their current position as nurses based on a discourse of knowledge in relation to the practical and theoretical knowledge they encounter in the master's programme. This article concludes by recommending that attention should be paid to developing APN role models in the current Swedish healthcare system. Copyright © 2017 Elsevier Ltd. All rights reserved.

Chemical Sensing Systems that Utilize Soft Electronics on Thin Elastomeric Substrates with Open Cellular Designs

PubMed Central

Lee, Yoon Kyeung; Jang, Kyung-In; Ma, Yinji; Koh, Ahyeon; Chen, Hang; Jung, Han Na; Kim, Yerim; Kwak, Jean Won; Wang, Liang; Xue, Yeguang; Yang, Yiyuan; Tian, Wenlong; Jiang, Yu; Zhang, Yihui; Feng, Xue; Huang, Yonggang

2017-01-01

A collection of materials and device architectures are introduced for thin, stretchable arrays of ion sensors that mount on open cellular substrates to facilitate solution exchange for use in biointegrated electronics. The results include integration strategies and studies of fundamental characteristics in chemical sensing and mechanical response. The latter involves experimental measurements and theoretical simulations that establish important considerations in the design of low modulus, stretchable properties in cellular substrates, and in the realization of advanced capabilities in spatiotemporal mapping of chemicals' gradients. As the chemical composition of extracellular fluids contains valuable information related to biological function, the concepts introduced here have potential utility across a range of skin- and internal-organ-integrated electronics where soft mechanics, fluidic permeability, and advanced chemical sensing capabilities are key requirements. PMID:28989338

Concepts for a theoretical and experimental study of lifting rotor random loads and vibrations (further experiments with progressing/regressing rotor flapping modes), Phase 7-C

NASA Technical Reports Server (NTRS)

Hohenemser, K. H.; Crews, S. T.

1973-01-01

The experiments with progressing/regressing forced rotor flapping modes have been extended in several directions and the data processing method has been considerably refined. The 16 inch hingeless 2-bladed rotor model was equipped with a new set of high precision blades which removed previously encountered tracking difficulties at high advance ratio, so that tests up to .8 rotor advance ratio could be conducted. In addition to data with 1.20 blade natural flapping frequency data at 1.10 flapping frequency were obtained. Outside the wind tunnel, tests with a ground plate located at different distances below the rotor were conducted while recording the dynamic downflow at a station .2R below the rotor plane with a hot wire anemometer.

Using climate models to estimate the quality of global observational data sets.

PubMed

Massonnet, François; Bellprat, Omar; Guemas, Virginie; Doblas-Reyes, Francisco J

2016-10-28

Observational estimates of the climate system are essential to monitoring and understanding ongoing climate change and to assessing the quality of climate models used to produce near- and long-term climate information. This study poses the dual and unconventional question: Can climate models be used to assess the quality of observational references? We show that this question not only rests on solid theoretical grounds but also offers insightful applications in practice. By comparing four observational products of sea surface temperature with a large multimodel climate forecast ensemble, we find compelling evidence that models systematically score better against the most recent, advanced, but also most independent product. These results call for generalized procedures of model-observation comparison and provide guidance for a more objective observational data set selection. Copyright © 2016, American Association for the Advancement of Science.

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

NASA Astrophysics Data System (ADS)

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

2015-10-01

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

Prospects for direct social perception: a multi-theoretical integration to further the science of social cognition.

PubMed

Wiltshire, Travis J; Lobato, Emilio J C; McConnell, Daniel S; Fiore, Stephen M

2014-01-01

In this paper we suggest that differing approaches to the science of social cognition mirror the arguments between radical embodied and traditional approaches to cognition. We contrast the use in social cognition of theoretical inference and mental simulation mechanisms with approaches emphasizing a direct perception of others' mental states. We build from a recent integrative framework unifying these divergent perspectives through the use of dual-process theory and supporting social neuroscience research. Our elaboration considers two complementary notions of direct perception: one primarily stemming from ecological psychology and the other from enactive cognition theory. We use this as the foundation from which to offer an account of the informational basis for social information and assert a set of research propositions to further the science of social cognition. In doing so, we point out how perception of the minds of others can be supported in some cases by lawful information, supporting direct perception of social affordances and perhaps, mental states, and in other cases by cues that support indirect perceptual inference. Our goal is to extend accounts of social cognition by integrating advances across disciplines to provide a multi-level and multi-theoretic description that can advance this field and offer a means through which to reconcile radical embodied and traditional approaches to cognitive neuroscience.

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

PubMed

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

2017-05-01

Models of attention often distinguish among attention subtypes, with classic models separating orienting, switching, and sustaining functions. Compared with other forms of attention, the neurophysiological basis of sustaining attention has received far less notice, yet it is known that momentary failures of sustained attention can have far-ranging negative effects in healthy individuals, and lasting sustained attention deficits are pervasive in clinical populations. In recent years, however, there has been increased interest in characterizing moment-to-moment fluctuations in sustained attention, in addition to the overall vigilance decrement, and understanding how these neurocognitive systems change over the life span and across various clinical populations. The use of novel neuroimaging paradigms and statistical approaches has allowed for better characterization of the neural networks supporting sustained attention and has highlighted dynamic interactions within and across multiple distributed networks that predict behavioral performance. These advances have also provided potential biomarkers to identify individuals with sustained attention deficits. These findings have led to new theoretical models explaining why sustaining focused attention is a challenge for individuals and form the basis for the next generation of sustained attention research, which seeks to accurately diagnose and develop theoretically driven treatments for sustained attention deficits that affect a variety of clinical populations. © 2017 New York Academy of Sciences.

Interfacing theories of program with theories of evaluation for advancing evaluation practice: Reductionism, systems thinking, and pragmatic synthesis.

PubMed

Chen, Huey T

2016-12-01

Theories of program and theories of evaluation form the foundation of program evaluation theories. Theories of program reflect assumptions on how to conceptualize an intervention program for evaluation purposes, while theories of evaluation reflect assumptions on how to design useful evaluation. These two types of theories are related, but often discussed separately. This paper attempts to use three theoretical perspectives (reductionism, systems thinking, and pragmatic synthesis) to interface them and discuss the implications for evaluation practice. Reductionism proposes that an intervention program can be broken into crucial components for rigorous analyses; systems thinking view an intervention program as dynamic and complex, requiring a holistic examination. In spite of their contributions, reductionism and systems thinking represent the extreme ends of a theoretical spectrum; many real-world programs, however, may fall in the middle. Pragmatic synthesis is being developed to serve these moderate- complexity programs. These three theoretical perspectives have their own strengths and challenges. Knowledge on these three perspectives and their evaluation implications can provide a better guide for designing fruitful evaluations, improving the quality of evaluation practice, informing potential areas for developing cutting-edge evaluation approaches, and contributing to advancing program evaluation toward a mature applied science. Copyright © 2016 Elsevier Ltd. All rights reserved.

Simultaneous spreading and evaporation: recent developments.

PubMed

Semenov, Sergey; Trybala, Anna; Rubio, Ramon G; Kovalchuk, Nina; Starov, Victor; Velarde, Manuel G

2014-04-01

The recent progress in theoretical and experimental studies of simultaneous spreading and evaporation of liquid droplets on solid substrates is discussed for pure liquids including nanodroplets, nanosuspensions of inorganic particles (nanofluids) and surfactant solutions. Evaporation of both complete wetting and partial wetting liquids into a nonsaturated vapour atmosphere are considered. However, the main attention is paid to the case of partial wetting when the hysteresis of static contact angle takes place. In the case of complete wetting the spreading/evaporation process proceeds in two stages. A theory was suggested for this case and a good agreement with available experimental data was achieved. In the case of partial wetting the spreading/evaporation of a sessile droplet of pure liquid goes through four subsequent stages: (i) the initial stage, spreading, is relatively short (1-2 min) and therefore evaporation can be neglected during this stage; during the initial stage the contact angle reaches the value of advancing contact angle and the radius of the droplet base reaches its maximum value, (ii) the first stage of evaporation is characterised by the constant value of the radius of the droplet base; the value of the contact angle during the first stage decreases from static advancing to static receding contact angle; (iii) during the second stage of evaporation the contact angle remains constant and equal to its receding value, while the radius of the droplet base decreases; and (iv) at the third stage of evaporation both the contact angle and the radius of the droplet base decrease until the drop completely disappears. It has been shown theoretically and confirmed experimentally that during the first and second stages of evaporation the volume of droplet to power 2/3 decreases linearly with time. The universal dependence of the contact angle during the first stage and of the radius of the droplet base during the second stage on the reduced time has been derived theoretically and confirmed experimentally. The theory developed for pure liquids is applicable also to nanofluids, where a good agreement with the available experimental data has been found. However, in the case of evaporation of surfactant solutions the process deviates from the theoretical predictions for pure liquids at concentration below critical wetting concentration and is in agreement with the theoretical predictions at concentrations above it. Crown Copyright © 2013. All rights reserved.

Challenged but not threatened: Managing health in advanced age.

PubMed

Wiles, Janine; Miskelly, Philippa; Stewart, Oneroa; Kerse, Ngaire; Rolleston, Anna; Gott, Merryn

2018-06-20

In this paper we reflect on discussions with people of advanced age in Āotearoa New Zealand, and draw on theoretical frameworks of resilience and place in old age, to explore insights about the ways older people maintain quality of life and health. Twenty community-dwelling people of advanced age (85+) were recruited in 2015-16 from a large multidisciplinary longitudinal study of advanced age. These twenty participated in interviews about health in advanced age, impact of illnesses, interactions with clinicians, access to information, support for managing health, and perceptions of primary care, medications, and other forms of assistance. We use a positioning theory framework drawing on thematic and narrative analysis to understand the dynamic ways people in advanced age position themselves and the ways they age well through speech acts and storylines. People in advanced age saw themselves as challenged, rather than threatened, by adversities, and positioned themselves as able to draw on a lifetime of experience and resourcefulness and collaborations with supporters to deal with challenges. Key strategies include downplaying illness and resisting biomedical discourses of complexity, positioning embodied selves as having agency, and creative adaptation in the face of loss. People in advanced age exhibit resilience, maintaining wellbeing, autonomy and good physical and mental quality of life even while living with challenges such as functional decline and multi-morbidities. These findings have significance for supporters of older people, emphasising the need to move away from a narrow focus on problems to working together WITH people in advanced age to offer a more holistic approach that encourages and enhances adaptation and flexibility, rather than rigid and counterproductive coping patterns. Copyright © 2018 Elsevier Ltd. All rights reserved.

A Learning Framework for Development.

ERIC Educational Resources Information Center

Chi, Michelene T. H.; Rees, Ernest T.

1983-01-01

Responding to recent advances in developmental and cognitive science research on knowledge acquisition, this report presents a theoretical framework for analyzing cognitive development as a process of learning. The first section summarizes three developmental characteristics recognized in both the Piagetian and the quantita experimental tradition:…

Knowledge-Based Information Retrieval.

ERIC Educational Resources Information Center

Ford, Nigel

1991-01-01

Discussion of information retrieval focuses on theoretical and empirical advances in knowledge-based information retrieval. Topics discussed include the use of natural language for queries; the use of expert systems; intelligent tutoring systems; user modeling; the need for evaluation of system effectiveness; and examples of systems, including…

Education and Social Cohesion for Economic Growth

ERIC Educational Resources Information Center

Camilleri, Mark A.; Camilleri, Adriana

2016-01-01

Relevant theoretical underpinnings suggest that higher education, continuous professional development and training provide numerous opportunities for societal advancement. This contribution posits that interventions in the realms of education can play a significant role in shaping key performance indicators for laudable social outcomes. It…

Towards a first implementation of the WLIMES approach in living system studies advancing the diagnostics and therapy in augmented personalized medicine.

PubMed

Simeonov, Plamen L

2017-12-01

The goal of this paper is to advance an extensible theory of living systems using an approach to biomathematics and biocomputation that suitably addresses self-organized, self-referential and anticipatory systems with multi-temporal multi-agents. Our first step is to provide foundations for modelling of emergent and evolving dynamic multi-level organic complexes and their sustentative processes in artificial and natural life systems. Main applications are in life sciences, medicine, ecology and astrobiology, as well as robotics, industrial automation, man-machine interface and creative design. Since 2011 over 100 scientists from a number of disciplines have been exploring a substantial set of theoretical frameworks for a comprehensive theory of life known as Integral Biomathics. That effort identified the need for a robust core model of organisms as dynamic wholes, using advanced and adequately computable mathematics. The work described here for that core combines the advantages of a situation and context aware multivalent computational logic for active self-organizing networks, Wandering Logic Intelligence (WLI), and a multi-scale dynamic category theory, Memory Evolutive Systems (MES), hence WLIMES. This is presented to the modeller via a formal augmented reality language as a first step towards practical modelling and simulation of multi-level living systems. Initial work focuses on the design and implementation of this visual language and calculus (VLC) and its graphical user interface. The results will be integrated within the current methodology and practices of theoretical biology and (personalized) medicine to deepen and to enhance the holistic understanding of life. Copyright © 2017 Elsevier B.V. All rights reserved.

In search of late time evolution self-similar scaling laws of Rayleigh-Taylor and Richtmyer-Meshkov hydrodynamic instabilities - recent theorical advance and NIF Discovery-Science experiments

NASA Astrophysics Data System (ADS)

Shvarts, Dov

2017-10-01

Hydrodynamic instabilities, and the mixing that they cause, are of crucial importance in describing many phenomena, from very large scales such as stellar explosions (supernovae) to very small scales, such as inertial confinement fusion (ICF) implosions. Such mixing causes the ejection of stellar core material in supernovae, and impedes attempts at ICF ignition. The Rayleigh-Taylor instability (RTI) occurs at an accelerated interface between two fluids with the lower density accelerating the higher density fluid. The Richtmyer-Meshkov (RM) instability occurs when a shock wave passes an interface between the two fluids of different density. In the RTI, buoyancy causes ``bubbles'' of the light fluid to rise through (penetrate) the denser fluid, while ``spikes'' of the heavy fluid sink through (penetrate) the lighter fluid. With realistic multi-mode initial conditions, in the deep nonlinear regime, the mixing zone width, H, and its internal structure, progress through an inverse cascade of spatial scales, reaching an asymptotic self-similar evolution: hRT =αRT Agt2 for RT and hRM =αRM tθ for RM. While this characteristic behavior has been known for years, the self-similar parameters αRT and θRM and their dependence on dimensionality and density ratio have continued to be intensively studied and a relatively wide distribution of those values have emerged. This talk will describe recent theoretical advances in the description of this turbulent mixing evolution that sheds light on the spread in αRT and θRM. Results of new and specially designed experiments, done by scientists from several laboratories, were performed recently using NIF, the only facility that is powerful enough to reach the self-similar regime, for quantitative testing of this theoretical advance, will be presented.

Same-day booking: success in a Canadian family practice.

PubMed

Mitchell, Victoria

2008-03-01

Patients in a family practice had to wait 6 weeks for an appointment. To improve patient care by facilitating access to timely appointments. An FP from Halifax, NS, implemented advanced access in her practice. Advanced access is a same-day booking system, which has been shown to reduce or eliminate patient backlogs without the addition of resources. Theoretically, it can be put into effect in any practice with a stable backlog (which indicates that supply and demand are well matched). The first step to implement the advanced access system was to clear the existing appointment backlog. During a 6-week "boot camp" period, all prebooked patients and patients who called requesting same-day appointments were seen (between 50 and 60 patients per day). Same-day appointment rules apply to almost all patients. Staff begin accepting calls at 8:00 AM, and patients request the most convenient time available. Baseline and postimplementation data are not available, as this was not a formal research study. Nevertheless, this FP from Halifax who implemented advanced access experienced the following in her practice: elimination of patient backlog, fewer no-shows, patients' happiness with the system, increase in physician and staff morale, and stability in physician income. Formal feasibility studies and research evaluating patient outcomes, cost effectiveness, and physician and patient satisfaction in a variety of practice settings would help Canadian FPs decide if same-day booking could be successfully implemented in their practices.

Clinical veterinary proteomics: Techniques and approaches to decipher the animal plasma proteome.

PubMed

Ghodasara, P; Sadowski, P; Satake, N; Kopp, S; Mills, P C

2017-12-01

Over the last two decades, technological advancements in the field of proteomics have advanced our understanding of the complex biological systems of living organisms. Techniques based on mass spectrometry (MS) have emerged as powerful tools to contextualise existing genomic information and to create quantitative protein profiles from plasma, tissues or cell lines of various species. Proteomic approaches have been used increasingly in veterinary science to investigate biological processes responsible for growth, reproduction and pathological events. However, the adoption of proteomic approaches by veterinary investigators lags behind that of researchers in the human medical field. Furthermore, in contrast to human proteomics studies, interpretation of veterinary proteomic data is difficult due to the limited protein databases available for many animal species. This review article examines the current use of advanced proteomics techniques for evaluation of animal health and welfare and covers the current status of clinical veterinary proteomics research, including successful protein identification and data interpretation studies. It includes a description of an emerging tool, sequential window acquisition of all theoretical fragment ion mass spectra (SWATH-MS), available on selected mass spectrometry instruments. This newly developed data acquisition technique combines advantages of discovery and targeted proteomics approaches, and thus has the potential to advance the veterinary proteomics field by enhancing identification and reproducibility of proteomics data. Copyright © 2017 Elsevier Ltd. All rights reserved.

Leading change: a concept analysis.

PubMed

Nelson-Brantley, Heather V; Ford, Debra J

2017-04-01

To report an analysis of the concept of leading change. Nurses have been called to lead change to advance the health of individuals, populations, and systems. Conceptual clarity about leading change in the context of nursing and healthcare systems provides an empirical direction for future research and theory development that can advance the science of leadership studies in nursing. Concept analysis. CINAHL, PubMed, PsycINFO, Psychology and Behavioral Sciences Collection, Health Business Elite and Business Source Premier databases were searched using the terms: leading change, transformation, reform, leadership and change. Literature published in English from 2001 - 2015 in the fields of nursing, medicine, organizational studies, business, education, psychology or sociology were included. Walker and Avant's method was used to identify descriptions, antecedents, consequences and empirical referents of the concept. Model, related and contrary cases were developed. Five defining attributes of leading change were identified: (a) individual and collective leadership; (b) operational support; (c) fostering relationships; (d) organizational learning; and (e) balance. Antecedents were external or internal driving forces and organizational readiness. The consequences of leading change included improved organizational performance and outcomes and new organizational culture and values. A theoretical definition and conceptual model of leading change were developed. Future studies that use and test the model may contribute to the refinement of a middle-range theory to advance nursing leadership research and education. From this, empirically derived interventions that prepare and enable nurses to lead change to advance health may be realized. © 2016 John Wiley & Sons Ltd.

X-ray free-electron laser studies of dense plasmas

NASA Astrophysics Data System (ADS)

Vinko, Sam M.

2015-10-01

> The high peak brightness of X-ray free-electron lasers (FELs), coupled with X-ray optics enabling the focusing of pulses down to sub-micron spot sizes, provides an attractive route to generating high energy-density systems on femtosecond time scales, via the isochoric heating of solid samples. Once created, the fundamental properties of these plasmas can be studied with unprecedented accuracy and control, providing essential experimental data needed to test and benchmark commonly used theoretical models and assumptions in the study of matter in extreme conditions, as well as to develop new predictive capabilities. Current advances in isochoric heating and spectroscopic plasma studies on X-ray FELs are reviewed and future research directions and opportunities discussed.

The effects of detailed chemistry and transport on microgravity droplet combustion

NASA Technical Reports Server (NTRS)

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

1995-01-01

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

Modeling of scattering from ice surfaces

NASA Astrophysics Data System (ADS)

Dahlberg, Michael Ross

Theoretical research is proposed to study electromagnetic wave scattering from ice surfaces. A mathematical formulation that is more representative of the electromagnetic scattering from ice, with volume mechanisms included, and capable of handling multiple scattering effects is developed. This research is essential to advancing the field of environmental science and engineering by enabling more accurate inversion of remote sensing data. The results of this research contributed towards a more accurate representation of the scattering from ice surfaces, that is computationally more efficient and that can be applied to many remote-sensing applications.

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

Chinn, D J

This month's issue has the following articles: (1) The Edward Teller Centennial--Commentary by George H. Miller; (2) Edward Teller's Century: Celebrating the Man and His Vision--Colleagues at the Laboratory remember Edward Teller, cofounder of Lawrence Livermore, adviser to U.S. presidents, and physicist extraordinaire, on the 100th anniversary of his birth; (3) Quark Theory and Today's Supercomputers: It's a Match--Thanks to the power of BlueGene/L, Livermore has become an epicenter for theoretical advances in particle physics; and (4) The Role of Dentin in Tooth Fracture--Studies on tooth dentin show that its mechanical properties degrade with age.

The workload book: Assessment of operator workload to engineering systems

NASA Technical Reports Server (NTRS)

Gopher, D.

1983-01-01

The structure and initial work performed toward the creation of a handbook for workload analysis directed at the operational community of engineers and human factors psychologists are described. The goal, when complete, will be to make accessible to such individuals the results of theoretically-based research that are of practical interest and utility in the analysis and prediction of operator workload in advanced and existing systems. In addition, the results of laboratory study focused on the development of a subjective rating technique for workload that is based on psychophysical scaling techniques are described.

A Study Protocol for Tracking Quality of Life Among U.S. Service Members Wounded in Iraq and Afghanistan: The Wounded Warrior Recovery Project

DTIC Science & Technology

2014-03-01

Freedorn and Iraqi Freedotn combat injury to improve care and treatment, and prevent poor physical, psychological , and social outcomes. We describe the...and Iraqi Freedom (OEF/OIF) is the highest in tnodem history primarily because of advanced protective gear and rapid effective medical care.’^ To date...useful to assess the need for care and rehabilitation.’" ’ ’ A theoretical model of trauma and its effect on QOL, devel- oped by Sprangers and Schwartz

The Teamwork Assessment Scale: A Novel Instrument to Assess Quality of Undergraduate Medical Students' Teamwork Using the Example of Simulation-based Ward-Rounds.

PubMed

Kiesewetter, Jan; Fischer, Martin R

2015-01-01

Simulation-based teamwork trainings are considered a powerful training method to advance teamwork, which becomes more relevant in medical education. The measurement of teamwork is of high importance and several instruments have been developed for various medical domains to meet this need. To our knowledge, no theoretically-based and easy-to-use measurement instrument has been published nor developed specifically for simulation-based teamwork trainings of medical students. Internist ward-rounds function as an important example of teamwork in medicine. The purpose of this study was to provide a validated, theoretically-based instrument that is easy-to-use. Furthermore, this study aimed to identify if and when rater scores relate to performance. Based on a theoretical framework for teamwork behaviour, items regarding four teamwork components (Team Coordination, Team Cooperation, Information Exchange, Team Adjustment Behaviours) were developed. In study one, three ward-round scenarios, simulated by 69 students, were videotaped and rated independently by four trained raters. The instrument was tested for the embedded psychometric properties and factorial structure. In study two, the instrument was tested for construct validity with an external criterion with a second set of 100 students and four raters. In study one, the factorial structure matched the theoretical components but was unable to separate Information Exchange and Team Cooperation. The preliminary version showed adequate psychometric properties (Cronbach's α=.75). In study two, the instrument showed physician rater scores were more reliable in measurement than those of student raters. Furthermore, a close correlation between the scale and clinical performance as an external criteria was shown (r=.64) and the sufficient psychometric properties were replicated (Cronbach's α=.78). The validation allows for use of the simulated teamwork assessment scale in undergraduate medical ward-round trainings to reliably measure teamwork by physicians. Further studies are needed to verify the applicability of the instrument.

The Teamwork Assessment Scale: A Novel Instrument to Assess Quality of Undergraduate Medical Students' Teamwork Using the Example of Simulation-based Ward-Rounds

PubMed Central

Kiesewetter, Jan; Fischer, Martin R.

2015-01-01

Background: Simulation-based teamwork trainings are considered a powerful training method to advance teamwork, which becomes more relevant in medical education. The measurement of teamwork is of high importance and several instruments have been developed for various medical domains to meet this need. To our knowledge, no theoretically-based and easy-to-use measurement instrument has been published nor developed specifically for simulation-based teamwork trainings of medical students. Internist ward-rounds function as an important example of teamwork in medicine. Purposes: The purpose of this study was to provide a validated, theoretically-based instrument that is easy-to-use. Furthermore, this study aimed to identify if and when rater scores relate to performance. Methods: Based on a theoretical framework for teamwork behaviour, items regarding four teamwork components (Team Coordination, Team Cooperation, Information Exchange, Team Adjustment Behaviours) were developed. In study one, three ward-round scenarios, simulated by 69 students, were videotaped and rated independently by four trained raters. The instrument was tested for the embedded psychometric properties and factorial structure. In study two, the instrument was tested for construct validity with an external criterion with a second set of 100 students and four raters. Results: In study one, the factorial structure matched the theoretical components but was unable to separate Information Exchange and Team Cooperation. The preliminary version showed adequate psychometric properties (Cronbach’s α=.75). In study two, the instrument showed physician rater scores were more reliable in measurement than those of student raters. Furthermore, a close correlation between the scale and clinical performance as an external criteria was shown (r=.64) and the sufficient psychometric properties were replicated (Cronbach’s α=.78). Conclusions: The validation allows for use of the simulated teamwork assessment scale in undergraduate medical ward-round trainings to reliably measure teamwork by physicians. Further studies are needed to verify the applicability of the instrument. PMID:26038684

Need Assessment of Computer Science and Engineering Graduates

NASA Astrophysics Data System (ADS)

Surakka, Sami; Malmi, Lauri

2005-06-01

This case study considered the syllabus of the first and second year studies in computer science. The aim of the study was to reveal which topics covered in the syllabi were really needed during the following years of study or in working life. The program that was assessed in the study was a Masters program in computer science and engineering at a university of technology in Finland. The necessity of different subjects for the advanced studies (years 3? ?5) and for working life was assessed using four content analyses: (a) the course catalog of the institution where this study was carried out, (b) employment reports that were attached to the applications for internship credits, (c) masters theses, and (d) job advertisements in a newspaper. The results of the study imply that the necessity of physics for the advanced study and work was very low compared to the extent to which it was studied. On the other hand, the necessity for mathematics was moderate, and it had remained quite steady during the period 1989? ?2002. The most necessary computer science topic was programming. Also telecommunications and networking was needed often, whereas theoretical computer science was needed quite rarely.

Energetic particle-driven compressional Alfvén eigenmodes and prospects for ion cyclotron emission studies in fusion plasmas

DOE PAGES

Gorelenkov, N. N.

2016-10-01

As a fundamental plasma oscillation the compressional Alfvén waves (CAW) are interesting for plasma scientists both academically and in applications for fusion plasmas. They are believed to be responsible for the ion cyclotron emission (ICE) observed in many tokamaks. The theory of CAW and ICE was significantly advanced at the end of 20th century in particular motivated by first DT experiments on TFTR and subsequent JET DT experimental studies. More recently, ICE theory was advanced by ST (or spherical torus) experiments with the detailed theoretical and experimental studies of the properties of each instability signal. There the instability responsible formore » ICE signals previously indistinguishable in high aspect ratio tokamaks became the subjects of experimental studies. We discuss further the prospects of ICE theory and its applications for future burning plasma (BP) experiments such as the ITER tokamak-reactor prototype being build in France where neutrons and gamma rays escaping the plasma create extremely challenging conditions for fusion alpha particle diagnostics.a« less

Recent advances in exploring the neural underpinnings of auditory scene perception

PubMed Central

Snyder, Joel S.; Elhilali, Mounya

2017-01-01

Studies of auditory scene analysis have traditionally relied on paradigms using artificial sounds—and conventional behavioral techniques—to elucidate how we perceptually segregate auditory objects or streams from each other. In the past few decades, however, there has been growing interest in uncovering the neural underpinnings of auditory segregation using human and animal neuroscience techniques, as well as computational modeling. This largely reflects the growth in the fields of cognitive neuroscience and computational neuroscience and has led to new theories of how the auditory system segregates sounds in complex arrays. The current review focuses on neural and computational studies of auditory scene perception published in the past few years. Following the progress that has been made in these studies, we describe (1) theoretical advances in our understanding of the most well-studied aspects of auditory scene perception, namely segregation of sequential patterns of sounds and concurrently presented sounds; (2) the diversification of topics and paradigms that have been investigated; and (3) how new neuroscience techniques (including invasive neurophysiology in awake humans, genotyping, and brain stimulation) have been used in this field. PMID:28199022

Interactive 3D visualization for theoretical virtual observatories

NASA Astrophysics Data System (ADS)

Dykes, T.; Hassan, A.; Gheller, C.; Croton, D.; Krokos, M.

2018-06-01

Virtual observatories (VOs) are online hubs of scientific knowledge. They encompass a collection of platforms dedicated to the storage and dissemination of astronomical data, from simple data archives to e-research platforms offering advanced tools for data exploration and analysis. Whilst the more mature platforms within VOs primarily serve the observational community, there are also services fulfilling a similar role for theoretical data. Scientific visualization can be an effective tool for analysis and exploration of data sets made accessible through web platforms for theoretical data, which often contain spatial dimensions and properties inherently suitable for visualization via e.g. mock imaging in 2D or volume rendering in 3D. We analyse the current state of 3D visualization for big theoretical astronomical data sets through scientific web portals and virtual observatory services. We discuss some of the challenges for interactive 3D visualization and how it can augment the workflow of users in a virtual observatory context. Finally we showcase a lightweight client-server visualization tool for particle-based data sets, allowing quantitative visualization via data filtering, highlighting two example use cases within the Theoretical Astrophysical Observatory.

Theoretical integration and the psychology of sport injury prevention.

PubMed

Chan, Derwin King-Chung; Hagger, Martin S

2012-09-01

Integrating different theories of motivation to facilitate or predict behaviour change has received an increasing amount of attention within the health, sport and exercise science literature. A recent review article in Sports Medicine, by Keats, Emery and Finch presented an integrated model using two prominent theories in social psychology, self-determination theory (SDT) and the theory of planned behaviour (TPB), aimed at explaining and enhancing athletes' adherence to sport injury prevention. While echoing their optimistic views about the utility of these two theories to explain adherence in this area and the virtues of theoretical integration, we would like to seize this opportunity to clarify several conceptual principles arising from the authors' integration of the theories. Clarifying the theoretical assumptions and explaining precisely how theoretical integration works is crucial not only for improving the comprehensiveness of the integrated framework for predicting injury prevention behaviour, but also to aid the design of effective intervention strategies targeting behavioural adherence. In this article, we use the integration of SDT and TPB as an example to demonstrate how theoretical integration can advance the understanding of injury prevention behaviour in sport.

A theoretical model of continuity in anxiety and links to academic achievement in disaster-exposed school children.

PubMed

Weems, Carl F; Scott, Brandon G; Taylor, Leslie K; Cannon, Melinda F; Romano, Dawn M; Perry, Andre M

2013-08-01

This study tested a theoretical model of continuity in anxious emotion and its links to academic achievement in disaster-exposed youth. An urban school based sample of youths (n = 191; Grades 4-8) exposed to Hurricane Katrina were assessed at 24 months (Time 1) and then again at 30 months (Time 2) postdisaster. Academic achievement was assessed through end of the school year standardized test scores (~31 months after Katrina). The results suggest that the association of traumatic stress to academic achievement was indirect via linkages from earlier (Time 1) posttraumatic stress disorder symptoms that predicted later (Time 2) test anxiety. Time 2 test anxiety was then negatively associated with academic achievement. Age and gender invariance testing suggested strong consistency across gender and minor developmental variation in the age range examined. The model presented advances the developmental understanding of the expression of anxious emotion and its links to student achievement among disaster-exposed urban school children. The findings highlight the importance of identifying heterotypic continuity in anxiety and suggest potential applied and policy directions for disaster-exposed youth. Avenues for future theoretical refinement are also discussed.

A Rhetoric of Controversy.

ERIC Educational Resources Information Center

Phillips, Kendall R.

1999-01-01

Contributes to scholarship advancing the understanding of human communication by exploring the concept of controversy within a theoretical framework which does not presume the existence of a public sphere. Suggests an alternative perspective based on the intersection of moments of opportunity and specific sites of discourse. Applies this…

A Brief History of Knowledge Building

ERIC Educational Resources Information Center

Scardamalia, Marlene; Bereiter, Carl

2010-01-01

Knowledge Building as a theoretical, pedagogical, and technological innovation focuses on the 21st century need to work creatively with knowledge. The team now advancing Knowledge Building spans multiple disciplines, sectors, and cultural contexts. Several teacher-researcher-government partnerships have formed to bring about the systemic changes…

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

Molinero, Valeria; Kay, Bruce D.

This Special Topic on the Chemical Physics of Interfacial and Confined Water contains a collection of original research papers that showcase recent theoretical and experimental advances in the field. These papers provide a timely discussion of fundamental aspects of interfacial and confined water that are important in both natural environments and engineered applications.

Towards a Cyber-Constructivist Perspective (CCP) of Educational Design

ERIC Educational Resources Information Center

Luppicini, Rocci

2003-01-01

This theoretical paper utilizes cybernetic-­based approaches (Bopry, 1999; Wiener, 1954) and communications theory (Habermas, 1984, 1990; Krippendorff, 1994) to advance knowledge of constructivist learning. I argue that past educational research literature on constructivist learning is partly responsible for limiting how educational designers…

Towards a Cyber-Constructivist Perspective (CCP) of Educational Design.

ERIC Educational Resources Information Center

Luppicini, Rocci

2003-01-01

This theoretical paper uses cybernetic-based approaches and communications theory to advance knowledge of constructivist learning. Explores a cyber-constructivist perspective (CCP) as a tool for increasing awareness of factors that may contribute to effective constructivist educational design within learning communities, and discusses advantages…

Improving Student Performance Outcomes and Graduation Rates through Institutional Partnerships

ERIC Educational Resources Information Center

Roggow, Michael J.

2014-01-01

This chapter explores a grant-sponsored program and examines the role of departmental and institutional collaborations in advancing student performance outcomes. It provides a theoretical framework and a description of best practices for ensuring the success of first-generation urban community college students.

Practical secure quantum communications

NASA Astrophysics Data System (ADS)

Diamanti, Eleni

2015-05-01

We review recent advances in the field of quantum cryptography, focusing in particular on practical implementations of two central protocols for quantum network applications, namely key distribution and coin flipping. The former allows two parties to share secret messages with information-theoretic security, even in the presence of a malicious eavesdropper in the communication channel, which is impossible with classical resources alone. The latter enables two distrustful parties to agree on a random bit, again with information-theoretic security, and with a cheating probability lower than the one that can be reached in a classical scenario. Our implementations rely on continuous-variable technology for quantum key distribution and on a plug and play discrete-variable system for coin flipping, and necessitate a rigorous security analysis adapted to the experimental schemes and their imperfections. In both cases, we demonstrate the protocols with provable security over record long distances in optical fibers and assess the performance of our systems as well as their limitations. The reported advances offer a powerful toolbox for practical applications of secure communications within future quantum networks.

New sophistry: self-deception in the nursing academy.

PubMed

Garrett, Bernard M

2016-07-01

In this essay, I advance an argument against the expansion and acceptance of postmodern metaphysical antirealist ideologies in the development of nursing theory in North America. I suggest mystical theoretical explanations of care, the rejection of empirical epistemology, and a return to divinity in nursing represent an intellectual dead end, as these ideas do little to help resolve real-world health issues and also negate the need for the academic discrimination of bad ideas. I examine some of the philosophical foundations of nursing theory and deconstruct some of the more preternatural theories that have become established as the dominant conventional wisdom in the academy. It is argued that this can be characterized as a form of self-deception, and overall has had a negative impact on advancement of the nursing profession and public health care. Reasons behind the widespread acceptance of these irrational theoretical stances in nursing and the ongoing support for mystical therapeutic interventions are explored. © 2016 John Wiley & Sons Ltd.

Novel technologies and theoretical models in radiation therapy of cancer patients using 6.3 MeV fast neutrons produced by U-120 cyclotron

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

Musabaeva, L. I., E-mail: musabaevaLI@oncology.tomsk.ru; Lisin, V. A., E-mail: Lisin@oncology.tomsk.ru; Startseva, Zh. A., E-mail: zhanna.alex@rambler.ru

The analysis of clinical use of neutron therapy with 6 MeV fast neutrons compared to conventional radiation therapy was carried out. The experience of using neutron and mixed neutron and photon therapy in patients with different radio-resistant malignant tumors shows the necessity of further studies and development of the novel approaches to densely-ionizing radiation. The results of dosimetry and radiobiological studies have been the basis for planning clinical programs for neutron therapy. Clinical trials over the past 30 years have shown that neutron therapy successfully destroys radio-resistant cancers, including salivary gland tumors, adenoidcystic carcinoma, inoperable sarcomas, locally advanced head andmore » neck tumors, and locally advanced prostate cancer. Radiation therapy with 6.3 MeV fast neutrons used alone and in combination with photon therapy resulted in improved long-term treatment outcomes in patients with radio-resistant malignant tumors.« less

Design of Functional Materials based on Liquid Crystalline Droplets.

PubMed

Miller, Daniel S; Wang, Xiaoguang; Abbott, Nicholas L

2014-01-14

This brief perspective focuses on recent advances in the design of functional soft materials that are based on confinement of low molecular weight liquid crystals (LCs) within micrometer-sized droplets. While the ordering of LCs within micrometer-sized domains has been explored extensively in polymer-dispersed LC materials, recent studies performed with LC domains with precisely defined size and interfacial chemistry have unmasked observations of confinement-induced ordering of LCs that do not follow previously reported theoretical predictions. These new findings, which are enabled in part by advances in the preparation of LCs encapsulated in polymeric shells, are opening up new opportunities for the design of soft responsive materials based on surface-induced ordering transitions. These materials are also providing new insights into the self-assembly of biomolecular and colloidal species at defects formed by LCs confined to micrometer-sized domains. The studies presented in this perspective serve additionally to highlight gaps in knowledge regarding the ordering of LCs in confined systems.

Transformation thermodynamics and heat cloaking: a review

NASA Astrophysics Data System (ADS)

Raza, Muhammad; Liu, Yichao; Lee, El Hang; Ma, Yungui

2016-04-01

This article is a review of the advances and progresses in the field of heat cloaking which is being realized using metamaterials. Heat cloaking has been a particularly important subject of study due to its potential multidimensional applications. The process which manipulates the heat flux in such a way that it can neither enter into the cloaked region nor be distorted outside is called thermal cloaking. Transformation optics has made the hitherto inconceivable advancements in the field of thermodynamics possible with the remarkable assistance of metamaterials. In this article we present a review of the work done in the field of heat cloaking, its progress and outlook. We discuss the theoretical and experimental studies, models, design managements, implementations and behaviors of thermal invisibility cloaking and related devices. This review is intended to help further develop practical and applicable concepts, examine fabrication techniques for a variety of different invisibility cloaking devices and systems, and to pave a way for the new avenues leading to new future technologies.

Trying something new.

PubMed

Condon, Barbara Backer

2013-01-01

Trying something new is a universal living experience of health. Although trying something new frequently occurs in healthcare, its meaning has never explicitly been studied. Parse's humanbecoming school of thought is the theoretical perspective for this study. The research question for this study is: What is the structure of the living experience of trying something new? The purpose of this study was to advance nursing science. Parse's qualitative phenomenological-hermeneutic research method was used to guide this study. Participants were 8 men and 2 women, ages 29 to 65 who utilize an outpatient mental health facility in the Midwest. Data were collected with dialogical engagement. The major finding of the study is the structure: Trying something new is engaging in capricious exploitations with vacillating sentiments, as wistful contemplation surfaces with disparate affiliations.

Computing fluid-particle interaction forces for nano-suspension droplet spreading: molecular dynamics simulations

NASA Astrophysics Data System (ADS)

Zhou, Weizhou; Shi, Baiou; Webb, Edmund

2017-11-01

Recently, there are many experimental and theoretical studies to understand and control the dynamic spreading of nano-suspension droplets on solid surfaces. However, fundamental understanding of driving forces dictating the kinetics of nano-suspension wetting and spreading, especially capillary forces that manifest during the process, is lacking. Here, we present results from atomic scale simulations that were used to compute forces between suspended particles and advancing liquid fronts. The role of nano-particle size, particle loading, and interaction strength on forces computed from simulations will be discussed. Results demonstrate that increasing the particle size dramatically changes observed wetting behavior from depinning to pinning. From simulations on varying particle size, a relationship between computed forces and particle size is advanced and compared to existing expressions in the literature. High particle loading significantly slowed spreading kinetics, by introducing tortuous transport paths for liquid delivery to the advancing contact line. Lastly, we show how weakening the interaction between the particle and the underlying substrate can change a system from exhibiting pinning behavior to de-pinning.

Developing a Theoretical Framework to Illustrate Associations Among Patient Satisfaction, Body Image and Quality of Life for Women Undergoing Breast Reconstruction

PubMed Central

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

2013-01-01

Within the field of breast reconstruction there is increasing focus on patient-reported outcomes related to satisfaction, body image, and quality of life. These outcomes are deemed highly relevant because the primary goal of breast reconstruction is to recreate the appearance of a breast (or breasts) that is satisfying to the patient. Prominent researchers have suggested the need to develop improved standards for outcome evaluation which can ultimately benefit patients as well as physicians. The purpose of this article is to summarize key findings in the area of patient-reported outcomes for breast reconstruction and introduce a theoretical framework for advancing research in this field. We conducted an extensive literature review of outcome studies for breast reconstruction focusing on patient-reported results. We developed a theoretical framework illustrating core patient-reported outcomes related to breast reconstruction and factors associated with these outcomes. Our theoretical model highlights domains and distinguishing features of patient satisfaction, body image, and quality of life outcomes for women undergoing breast reconstruction. This model further identifies a broad range of variables (e.g., historical/premorbid influences, disease and treatment-related factors) that have been found to influence patient-reported outcomes and need to be taken into consideration when designing future research in this area. Additional attention is given to examining the relationship between patient reported outcomes and outside evaluation of breast reconstruction. Our proposed theoretical framework suggests key opportunities to expand research in this area with the goal of optimizing body image adjustment, satisfaction, and psychosocial outcomes for the individual patient. PMID:23380309

Central gender theoretical concepts in health research: the state of the art.

PubMed

Hammarström, Anne; Johansson, Klara; Annandale, Ellen; Ahlgren, Christina; Aléx, Lena; Christianson, Monica; Elwér, Sofia; Eriksson, Carola; Fjellman-Wiklund, Anncristine; Gilenstam, Kajsa; Gustafsson, Per E; Harryson, Lisa; Lehti, Arja; Stenberg, Gunilla; Verdonk, Petra

2014-02-01

Despite increasing awareness of the importance of gender perspectives in health science, there is conceptual confusion regarding the meaning and the use of central gender theoretical concepts. We argue that it is essential to clarify how central concepts are used within gender theory and how to apply them to health research. We identify six gender theoretical concepts as central and interlinked-but problematic and ambiguous in health science: sex, gender, intersectionality, embodiment, gender equity and gender equality. Our recommendations are that: the concepts sex and gender can benefit from a gender relational theoretical approach (i.e., a focus on social processes and structures) but with additional attention to the interrelations between sex and gender; intersectionality should go beyond additive analyses to study complex intersections between the major factors which potentially influence health and ensure that gendered power relations and social context are included; we need to be aware of the various meanings given to embodiment, which achieve an integration of gender and health and attend to different levels of analyses to varying degrees; and appreciate that gender equality concerns absence of discrimination between women and men while gender equity focuses on women's and men's health needs, whether similar or different. We conclude that there is a constant need to justify and clarify our use of these concepts in order to advance gender theoretical development. Our analysis is an invitation for dialogue but also a call to make more effective use of the knowledge base which has already developed among gender theorists in health sciences in the manner proposed in this paper.

Theoretical insight into reaction mechanisms of 2,4-dinitroanisole with hydroxyl radicals for advanced oxidation processes.

PubMed

Zhou, Yang; Liu, Xiaoqiang; Jiang, Weidong; Shu, Yuanjie

2018-01-24

The detailed degradation mechanism of an insensitive explosive, 2,4-dinitroanisole (DNAN), in advanced oxidation processes (AOPs) was investigated computationally at the M06-2X/6-311 + G(d,p)/SMD level of theory. Results obtained show that the addition-elimination reaction is the dominant mechanism. The phenol products formed can continue to be oxidized to benzoquinone radicals that are often detected by experiments and may be the initial reactants of ring-opening reactions. The H-abstraction reaction is an unavoidable competing mechanism; the intermediate generated can also undergo the process of addition-elimination reaction. The nitro departure reaction involves not only hydroxyl radical (•OH), but also other active substances (such as •H). More importantly, we found that AOP technology can easily degrade DNAN, similar to TNT and DNT. Thus, this method is worth trying in experiments. The conclusions of this work provide theoretical support for such experimental research. Graphical abstract Possible pathways of degradation by •OH radicals in advanced oxidation processes (AOPs) of the typical insensitive explosive 2,4-dinitroanisole (DNAN) were investigated by density functional theory (DFT) methods. Based on the Gibbs free energy barriers and intermediates, the dominant reaction mechanism was determined. The conclusions will be helpful in utilizing AOP technology to remove DNAN pollution.

PREFACE: Quantum Information, Communication, Computation and Cryptography

NASA Astrophysics Data System (ADS)

Benatti, F.; Fannes, M.; Floreanini, R.; Petritis, D.

2007-07-01

The application of quantum mechanics to information related fields such as communication, computation and cryptography is a fast growing line of research that has been witnessing an outburst of theoretical and experimental results, with possible practical applications. On the one hand, quantum cryptography with its impact on secrecy of transmission is having its first important actual implementations; on the other hand, the recent advances in quantum optics, ion trapping, BEC manipulation, spin and quantum dot technologies allow us to put to direct test a great deal of theoretical ideas and results. These achievements have stimulated a reborn interest in various aspects of quantum mechanics, creating a unique interplay between physics, both theoretical and experimental, mathematics, information theory and computer science. In view of all these developments, it appeared timely to organize a meeting where graduate students and young researchers could be exposed to the fundamentals of the theory, while senior experts could exchange their latest results. The activity was structured as a school followed by a workshop, and took place at The Abdus Salam International Center for Theoretical Physics (ICTP) and The International School for Advanced Studies (SISSA) in Trieste, Italy, from 12-23 June 2006. The meeting was part of the activity of the Joint European Master Curriculum Development Programme in Quantum Information, Communication, Cryptography and Computation, involving the Universities of Cergy-Pontoise (France), Chania (Greece), Leuven (Belgium), Rennes1 (France) and Trieste (Italy). This special issue of Journal of Physics A: Mathematical and Theoretical collects 22 contributions from well known experts who took part in the workshop. They summarize the present day status of the research in the manifold aspects of quantum information. The issue is opened by two review articles, the first by G Adesso and F Illuminati discussing entanglement in continuous variable systems, the second by T Prosen, discussing chaos and complexity in quantum systems. Both topics have theoretical as well as experimental relevance and are likely to witness a fast growing development in the near future. The remaining contributions present more specific and very recent results. They involve the study of the structure of quantum states and their estimation (B Baumgartner et al, C King et al, S Olivares et al, D Petz et al and W van Dam et al), of entanglement generation and its quantification (G Brida et al, F Ciccarello et al, G Costantini et al, O Romero-Isart et al, D Rossini et al, A Serafini et al and D Vitali et al), of randomness related effects on entanglement behaviour (I Akhalwaya et al, O Dahlsten et al and L Viola et al), and of abstract and applied aspects of quantum computation and communication (K Audenart, G M D'Ariano et al, N Datta et al, L C Kwek et al and M Nathanson et al). We would like to express our gratitude to the European Commission, the Abdus Salam ICTP, SISSA and Eurotech SpA (Amaro, Udine, Italy) for financial and/or logistic support. Special thanks also go to the workshop secretary Marina De Comelli, and the secretaries of the Department of Theoretical Physics, University of Trieste, Sabrina Gaspardis and Rosita Glavina for their precious help and assistance.

Experimental and theoretical study of the B(2)2Σ+ → X(1)2Σ+ system in the KSr molecule

NASA Astrophysics Data System (ADS)

Szczepkowski, Jacek; Grochola, Anna; Kowalczyk, Paweł; Dulieu, Olivier; Guérout, Romain; Żuchowski, Piotr S.; Jastrzebski, Włodzimierz

2018-05-01

Spectral bands for the B(2)2Σ+ → X(1)2Σ+ electronic transition in the doubly-polar open-shell KSr molecule are recorded at moderate resolution using the thermoluminescence technique. The spectra are simulated using three kinds of advanced electronic structure calculations, allowing for an assessment of their accuracy on one hand, and for the derivation of fundamental spectroscopic constants of the X(1)2Σ+ KSr ground state and the excited electronic state B(2)2Σ+ , on the other hand. These results should facilitate further studies aiming at creating ultracold bosonic or fermionic KSr molecules.

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

PubMed

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

2018-07-01

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

Aircraft engine sump-fire studies

NASA Technical Reports Server (NTRS)

Loomis, W. R.

1976-01-01

Results of ongoing experimental studies are reported in which a 125-millimeter-diameter-advanced-bearing test rig simulating an engine sump is being used to find the critical range of conditions for fires to occur. Design, material, and operating concepts and techniques are being studied with the objective of minimizing the problem. It has been found that the vapor temperature near a spark ignitor is most important in determining ignition potential. At temperatures producing oil vapor pressures below or much above the calculated flammability limits, fires have not been ignited. But fires have been routinely started within the theoretical flammability range. This indicates that generalizing the sump-fire problem may make it amenable to analysis, with the potential for realistic solutions.

Theoretical and computational studies of non-equilibrium and non-statistical dynamics in the gas phase, in the condensed phase and at interfaces.

PubMed

Spezia, Riccardo; Martínez-Nuñez, Emilio; Vazquez, Saulo; Hase, William L

2017-04-28

In this Introduction, we show the basic problems of non-statistical and non-equilibrium phenomena related to the papers collected in this themed issue. Over the past few years, significant advances in both computing power and development of theories have allowed the study of larger systems, increasing the time length of simulations and improving the quality of potential energy surfaces. In particular, the possibility of using quantum chemistry to calculate energies and forces 'on the fly' has paved the way to directly study chemical reactions. This has provided a valuable tool to explore molecular mechanisms at given temperatures and energies and to see whether these reactive trajectories follow statistical laws and/or minimum energy pathways. This themed issue collects different aspects of the problem and gives an overview of recent works and developments in different contexts, from the gas phase to the condensed phase to excited states.This article is part of the themed issue 'Theoretical and computational studies of non-equilibrium and non-statistical dynamics in the gas phase, in the condensed phase and at interfaces'. © 2017 The Author(s).

The SM and NLO Multileg and SM MC Working Groups: Summary Report

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

Alcaraz Maestre, J.; et al.

2012-03-01

The 2011 Les Houches workshop was the first to confront LHC data. In the two years since the previous workshop there have been significant advances in both soft and hard QCD, particularly in the areas of multi-leg NLO calculations, the inclusion of those NLO calculations into parton shower Monte Carlos, and the tuning of the non-perturbative parameters of those Monte Carlos. These proceedings describe the theoretical advances that have taken place, the impact of the early LHC data, and the areas for future development.

Developing a Network of and for Geometric Reasoning

ERIC Educational Resources Information Center

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

2015-01-01

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

Educational Psychology: Learning, Instruction, Assessment.

ERIC Educational Resources Information Center

McCormick, Christine B.; Pressley, Michael

This textbook for undergraduates reflects advances in the understanding of effective teaching and learning and is organized around the theme of promoting good information processing. The first part of the book describes the foundations of good thinking, and the second part introduces different theoretical perspectives on the construction of…

An Attributional Theory of Achievement Motivation and Emotion.

ERIC Educational Resources Information Center

Weiner, Bernard

1985-01-01

This article advances an attributional theory of motivation and emotion, with achievement strivings as the theoretical focus. Causes of success and failure share three common properties: locus, stability, and controllability. Stability of causes influences changes in expectancy of success. Expectancy and affect guide motivated behavior.…

Defining Creativity with Discovery

ERIC Educational Resources Information Center

Martin, Lee; Wilson, Nick

2017-01-01

The standard definition of creativity has enabled significant empirical and theoretical advances, yet contains philosophical conundrums concerning the nature of novelty and the role of recognition and values. This work offers an act of conceptual valeting that addresses these issues. In doing so, creativity definitions are extended through the use…

Theorising Critical HRD: A Paradox of Intricacy and Discrepancy

ERIC Educational Resources Information Center

Trehan, Kiran; Rigg, Clare

2011-01-01

Purpose: This paper aims to advance theoretical understanding of the concept of "critical human resource development". Design/methodology/approach: This is a conceptual paper. Findings: Foregrounding questions of power, emotions and political dynamics within the analysis of organisational learning and development activity, critical approaches in…

Agronomic and environmental aspects of diazotrophic bacteria in irrigated rice fields

USDA-ARS?s Scientific Manuscript database

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

New Hydrodynamic Flows in Fluctuating Superconductors

NASA Astrophysics Data System (ADS)

Delacretaz, Luca; Lucas, Andy; Hartnoll, Sean; SITP Collaboration

Recent advances, both theoretical and experimental, have made it possible to observe hydrodynamic flow in electron systems such as graphene and extract hydrodynamic transport coefficients such as the shear viscosity. Following the same logic, I will show how certain flows in superconductors could show signatures of fluctuating superconductivity.

Handbook of Research on Practices and Outcomes in E-Learning: Issues and Trends

ERIC Educational Resources Information Center

Yang, Harrison Hao, Ed.; Yuen, Steve Chi-Yin, Ed.

2010-01-01

As education continues to integrate technological advancements into learning and instruction, a resource dedicated to the latest findings and implications becomes necessary. This handbook provides academicians, researchers, and practitioners with a comprehensive view of the historical, conceptual, theoretical, and practical perspectives of…

Boundary Management for Cognitive Behavioral Therapies

ERIC Educational Resources Information Center

Gottlieb, Michael C.; Younggren, Jeffrey N.; Murch, Kevin B.

2009-01-01

In recent years, the scholarship regarding professional boundaries has increased significantly in a variety of areas. Despite many advances in this line of research, less attention has been devoted to the question of boundary maintenance and its relationship to theoretical orientation. In this article we examine these issues for…

A Theoretical Framework for the Associations between Identity and Psychopathology

ERIC Educational Resources Information Center

Klimstra, Theo A.; Denissen, Jaap J. A.

2017-01-01

Identity research largely emerged from clinical observations. Decades of empirical work advanced the field in refining existing approaches and adding new approaches. Furthermore, the existence of linkages of identity with psychopathology is now well established. Unfortunately, both the directionality of effects between identity aspects and…

Cultural Learning Redux

ERIC Educational Resources Information Center

Tomasello, Michael

2016-01-01

M. Tomasello, A. Kruger, and H. Ratner (1993) proposed a theory of cultural learning comprising imitative learning, instructed learning, and collaborative learning. Empirical and theoretical advances in the past 20 years suggest modifications to the theory; for example, children do not just imitate but overimitate in order to identify and…

Development of an experiment for visible radiation measurements from a satellite

NASA Technical Reports Server (NTRS)

Sekera, Z.; Bradbury, R. E.

1973-01-01

The inversion problem, I.E., determining the atmospheric turbidity from polarimetry of radiation emerging from the earth's atmosphere, is presented. A major theoretical advance was made by finding a successful approximation for the forward peak scattering of aerosols together with a simplified characterization of particle size distributions. An engineering model of a multibarreled photopolarimeter suitable for operation from a satellite was evaluated in laboratory and high altitude jet aircraft tests. Comparison of the data from flights over the Mexican desert with theoretical curves for a Rayleigh atmosphere with negligible turbidity is in agreement.

Detection of long wavelength infrared at moderate temperatures

NASA Technical Reports Server (NTRS)

Tredwell, T. J.

1977-01-01

Technical approaches for the advanced development of 8-12 micrometer detectors operating at elevated temperatures were defined. The theoretical limits to performance of 8-12 micrometer quantum detectors (photoconductive and photovoltaic) and thermal detectors (pyroelectrics, bolometers etc). An analytic model of signal and noise in both quantum detectors and pyroelectric detectors was developed and candidate materials for both detector types were identified and examined. The present status of both quantum and thermal detectors was assessed as well as the parameters limiting operating temperature and detectivity. The areas of research and development likely to lead to detector performance near the theoretical limit are identified.

Scientific thinking in young children: theoretical advances, empirical research, and policy implications.

PubMed

Gopnik, Alison

2012-09-28

New theoretical ideas and empirical research show that very young children's learning and thinking are strikingly similar to much learning and thinking in science. Preschoolers test hypotheses against data and make causal inferences; they learn from statistics and informal experimentation, and from watching and listening to others. The mathematical framework of probabilistic models and Bayesian inference can describe this learning in precise ways. These discoveries have implications for early childhood education and policy. In particular, they suggest both that early childhood experience is extremely important and that the trend toward more structured and academic early childhood programs is misguided.

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

PubMed

Cable, Noriko

2014-01-01

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

Broadband, high-resolution investigation of advanced absorption line shapes at high temperature

NASA Astrophysics Data System (ADS)

Schroeder, Paul J.; Cich, Matthew J.; Yang, Jinyu; Swann, William C.; Coddington, Ian; Newbury, Nathan R.; Drouin, Brian J.; Rieker, Gregory B.

2017-08-01

Spectroscopic studies of planetary atmospheres and high-temperature processes (e.g., combustion) require absorption line-shape models that are accurate over extended temperature ranges. To date, advanced line shapes, like the speed-dependent Voigt and Rautian profiles, have not been tested above room temperature with broadband spectrometers. We investigate pure water vapor spectra from 296 to 1305 K acquired with a dual-frequency comb spectrometer spanning from 6800 to 7200 c m-1 at a point spacing of 0.0033 c m-1 and absolute frequency accuracy of <3.3 ×10-6c m-1 . Using a multispectral fitting analysis, we show that only the speed-dependent Voigt accurately models this temperature range with a single power-law temperature-scaling exponent for the broadening coefficients. Only the data from the analysis using this profile fall within theoretical predictions, suggesting that this mechanism captures the dominant narrowing physics for these high-temperature conditions.

Laser Ranging to the Moon: How Evolving Technology Enables New Science

NASA Astrophysics Data System (ADS)

Faller, James

2010-03-01

Technological advances have long been the enabler of scientific progress. The invention of the laser is a prime example of this symbiotic relationship between technical progress and scientific advances. The laser, which today is omnipresent in each of our lives, made its first appearance during the time that I was a graduate student in Professor Dicke's group at Princeton. A major change occurring during that time period was that technology was transforming the study of gravitational physics from just a theoretical subject into also an experimental subject where one could hope to measure things using by-then-available laboratory technologies and techniques. During this same time, the idea for the lunar laser ranging experiment was born. The history and accomplishments of this experiment--a still ongoing experiment which is one of the real scientific triumphs of NASA's Apollo program--will be given.

New and Advanced Picosecond Lasers for Tattoo Removal.

PubMed

Adatto, Maurice A; Amir, Ruthie; Bhawalkar, Jayant; Sierra, Rafael; Bankowski, Richard; Rozen, Doran; Dierickx, Christine; Lapidoth, Moshe

2017-01-01

Early methods of tattoo removal ultimately resulted in unacceptable cosmetic outcomes. While the introduction of laser technology was an improvement over the existing chemical, mechanical, and surgical procedures, the use of nonselective tattoo removal with carbon dioxide and argon lasers led to scarring. Q-switched lasers with nanosecond (10-9) pulse domains were considered to have revolutionized tattoo treatment, by selectively heating the tattoo particles, while reducing the adverse sequelae to adjacent normal skin. Theoretical considerations of restricting pulse duration, to heat tattoo particles to higher temperatures, proposed the use of sub-nanosecond pulses to target particles with thermal relaxation times lower than the nanosecond pulses in Q-switched lasers. Initial studies demonstrated that picosecond (10-12) pulses were more effective than nanosecond pulses in clearing black tattoos. Advances in picosecond technology led to the development of commercially available lasers, incorporating several different wavelengths, to further refine pigment targeting. © 2017 S. Karger AG, Basel.

Current State of Theoretical and Experimental Studies of the Voltage-Dependent Anion Channel (VDAC)

PubMed Central

Noskov, Sergei Yu.; Rostovtseva, Tatiana K.; Chamberlin, Adam C.; Teijido, Oscar; Jiang, Wei; Bezrukov, Sergey M.

2016-01-01

Voltage-dependent anion channel (VDAC), the major channel of the mitochondrial outer membrane provides a controlled pathway for respiratory metabolites in and out of the mitochondria. In spite of the wealth of experimental data from structural, biochemical, and biophysical investigations, the exact mechanisms governing selective ion and metabolite transport, especially the role of titratable charged residues and interactions with soluble cytosolic proteins, remain hotly debated in the field. The computational advances hold a promise to provide a much sought-after solution to many of the scientific disputes around solute and ion transport through VDAC and hence, across the mitochondrial outer membrane. In this review, we examine how Molecular Dynamics, Free Energy, and Brownian Dynamics simulations of the large β-barrel channel, VDAC, advanced our understanding. We will provide a short overview of non-conventional techniques and also discuss examples of how the modeling excursions into VDAC biophysics prospectively aid experimental efforts. PMID:26940625

Psychopathy and Personality: Advances and Debates.

PubMed

Miller, Joshua D; Lynam, Donald R

2015-12-01

Nine original articles comprise this special issue of the Journal of Personality addressing personality-based perspectives of psychopathy. In this introduction to the special issue, we review five advances and areas of agreement that are highlighted across the articles, including the utility of trait perspectives to psychopathy, the emergence of a prototypical trait profile of psychopathy, the importance of recognizing earlier developmental manifestations of psychopathy, the ongoing study and revelation of the basic neural underpinnings of psychopathy, and the important theoretical and empirical association between psychopathy and antisocial behavior. At the same time, several important debates remain, which are also highlighted in the special issue's articles. These debates center around the necessity and sufficiency of certain psychopathy traits, the role of traits alternatively labeled stable Extraversion, fearless dominance, or boldness, and the validity and utility of separating psychopathy from Machiavellianism as is done in research on the Dark Triad. © 2014 Wiley Periodicals, Inc.

Recent Advances in the Theory and Simulation of Model Colloidal Microphase Formers.

PubMed

Zhuang, Yuan; Charbonneau, Patrick

2016-08-18

This mini-review synthesizes our understanding of the equilibrium behavior of particle-based models with short-range attractive and long-range repulsive (SALR) interactions. These models, which can form stable periodic microphases, aim to reproduce the essence of colloidal suspensions with competing interparticle interactions. Ordered structures, however, have yet to be obtained in experiments. In order to better understand the hurdles to periodic microphase assembly, marked theoretical and simulation advances have been made over the past few years. Here, we present recent progress in the study of microphases in models with SALR interactions using liquid-state theory and density-functional theory as well as numerical simulations. Combining these various approaches provides a description of periodic microphases, and gives insights into the rich phenomenology of the surrounding disordered regime. Ongoing research directions in the thermodynamics of models with SALR interactions are also presented.

Materials science. Assembly of micro/nanomaterials into complex, three-dimensional architectures by compressive buckling.

PubMed

Xu, Sheng; Yan, Zheng; Jang, Kyung-In; Huang, Wen; Fu, Haoran; Kim, Jeonghyun; Wei, Zijun; Flavin, Matthew; McCracken, Joselle; Wang, Renhan; Badea, Adina; Liu, Yuhao; Xiao, Dongqing; Zhou, Guoyan; Lee, Jungwoo; Chung, Ha Uk; Cheng, Huanyu; Ren, Wen; Banks, Anthony; Li, Xiuling; Paik, Ungyu; Nuzzo, Ralph G; Huang, Yonggang; Zhang, Yihui; Rogers, John A

2015-01-09

Complex three-dimensional (3D) structures in biology (e.g., cytoskeletal webs, neural circuits, and vasculature networks) form naturally to provide essential functions in even the most basic forms of life. Compelling opportunities exist for analogous 3D architectures in human-made devices, but design options are constrained by existing capabilities in materials growth and assembly. We report routes to previously inaccessible classes of 3D constructs in advanced materials, including device-grade silicon. The schemes involve geometric transformation of 2D micro/nanostructures into extended 3D layouts by compressive buckling. Demonstrations include experimental and theoretical studies of more than 40 representative geometries, from single and multiple helices, toroids, and conical spirals to structures that resemble spherical baskets, cuboid cages, starbursts, flowers, scaffolds, fences, and frameworks, each with single- and/or multiple-level configurations. Copyright © 2015, American Association for the Advancement of Science.

Recent advances in quartz enhanced photoacoustic sensing

NASA Astrophysics Data System (ADS)

Patimisco, Pietro; Sampaolo, Angelo; Dong, Lei; Tittel, Frank K.; Spagnolo, Vincenzo

2018-03-01

This review aims to discuss the latest advancements in quartz-enhanced photoacoustic spectroscopy (QEPAS) based trace-gas sensing. Starting from the QEPAS basic physical principles, the most used QEPAS configurations will be described. This is followed by a detailed theoretical analysis and experimental study regarding the influence of quartz tuning forks (QTFs) geometry on their optoacoustic transducer performance. Furthermore, an overview of the latest developments in QEPAS trace-gas sensor technology employing custom QTFs will be reported. Results obtained by exploiting novel micro-resonator configurations, capable of increasing the QEPAS signal-to-noise ratio by more than two orders of magnitude and the utilization of QTF overtone flexural modes for QEPAS based sensing will be presented. A comparison of the QEPAS performance of different spectrophone configurations is reported based upon signal-to-noise ratio. Finally, a novel QEPAS approach allowing simultaneous dual-gas detection will be described.

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

PubMed

Ganguli, Suman; Hunt, C Anthony

2004-01-01

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

An experimental, theoretical and event-driven computational study of narrow vibrofluidised granular materials

NASA Astrophysics Data System (ADS)

Thornton, Anthony; Windows-Yule, Kit; Parker, David; Luding, Stefan

2017-06-01

We review simulations, experiments and a theoretical treatment of vertically vibrated granular media. The systems considered are confined in narrow quasi-two-dimensional and quasi-one-dimensional (column) geometries, where the vertical extension of the container is much larger than one or both horizontal lengths. The additional geometric constraint present in the column setup frustrates the convection state that is normally observed in wider geometries. We start by showing that the Event Driven (ED) simulation method is able to accurately reproduce the previously experimentally determined phase-diagram for vibrofludised granular materials. We then review two papers that used ED simulations to study narrow quasi-one-dimensional systems revealing a new phenomenon: collective oscillations of the grains with a characteristic frequency that is much lower than the frequency of energy injection. Theoretical work was then undertaken that is able to accurately predict the frequency of such an oscillation and Positron Emission Particle Tracking (PEPT) experiments were undertaken to provide the first experimental evidence of this new phenomenon. Finally, we briefly discuss ongoing work to create an open-source version of this ED via its integration in the existing open-source package MercuryDPM (http://MercuryDPM.org); which has many advanced features that are not found in other codes.

Optical studies of quantum confined nanostructures

NASA Astrophysics Data System (ADS)

Vamivakas, Anthony Nickolas

Recent advances in material growth techniques have led to the laboratory realization of quantum confined nanostructures. By engineering the geometry of these systems it is possible to tailor their optical, electrical and vibrational properties. We now envision integrated electronic and optical devices potentially harnessing quantum mechanical properties of photons, electrons or even phonons. The realization of these next generation devices requires parallel advances in both electrical and optical characterization techniques. In this dissertation we study the optical properties of both zero-dimensional (0D) InAs/GaAs semiconductor quantum dots (QDs) and one-dimensional (1D) single wall carbon nanotubes (SWNTs). We utilize high resolution optical microscopy and spectroscopy techniques to experimentally study both individual QDs and SWNTs. The effect of quantum confinement on light-matter interaction in SWNTs is theoretically investigated. InAs QDs grown by Stranski-Krastanow self-assembly are buried in a GaAs matrix. The planar barriers presented by the dielectric boundary between the GaAs and the host medium limits the optical access to the InAs QDs. Incorporating a numerical aperture increasing microlens (NAIL) into a fiber-based confocal microscope we demonstrate improved ability to couple photons to and from a single InAs QD. With such immersion lens techniques we measure a record 12% extinction of a far-field laser by a single InAs QD. Even typical QD extinction of 6% is visible using a dc power-meter without the need for phase sensitive lock-in detection. This experimental advance will make possible the study of single QDs interacting with engineered vector laser beams. In the optical characterization of SWNTs, one-phonon resonant Raman scattering is employed to measure a tube's electronic resonances and determine the physical diameter and chirality of the tube under study. Recent work has determined excitons dominate the optical response of semiconducting SWNTs. We develop a theory to model the exciton mediated resonant Raman scattering cross-section from a 1D system looking for excitonic signatures in the scattering line shape. Additionally, we theoretically study phonon confinement to a 1D SWNT and use these results to extract the electron-phonon coupling in SWNTs from our Raman measurements. Knowledge of the electron-phonon coupling is a crucial piece of information to characterize a SWNTs electrical transport properties.

Restoration in Its Natural Context: How Ecological Momentary Assessment Can Advance Restoration Research

PubMed Central

Beute, Femke; de Kort, Yvonne; IJsselsteijn, Wijnand

2016-01-01

More and more people use self-tracking technologies to track their psychological states, physiology, and behaviors to gain a better understanding of themselves or to achieve a certain goal. Ecological Momentary Assessment (EMA) also offers an excellent opportunity for restorative environments research, which examines how our physical environment (especially nature) can positively influence health and wellbeing. It enables investigating restorative health effects in everyday life, providing not only high ecological validity but also opportunities to study in more detail the dynamic processes playing out over time on recovery, thereby bridging the gap between laboratory (i.e., short-term effects) and epidemiological (long-term effects) research. We have identified four main areas in which self-tracking could help advance restoration research: (1) capturing a rich set of environment types and restorative characteristics; (2) distinguishing intra-individual from inter-individual effects; (3) bridging the gap between laboratory and epidemiological research; and (4) advancing theoretical insights by measuring a more broad range of effects in everyday life. This paper briefly introduces restorative environments research, then reviews the state of the art of self-tracking technologies and methodologies, discusses how these can be implemented to advance restoration research, and presents some examples of pioneering work in this area. PMID:27089352

Inter-station coda wavefield studies using a novel icequake database on Erebus volcano

NASA Astrophysics Data System (ADS)

Chaput, J. A.; Campillo, M.; Roux, P.; Aster, R. C.

2013-12-01

Recent theoretical advances pertaining to the properties of multiply scattered wavefields have yielded a plethora of numerical and controlled source studies aiming to better understand what information may be derived from these otherwise chaotic signals. Practically, multiply scattered wavefields are difficult to compare to numerically derived models due to a combination of source paucity/directionality and array density limitations, particularly in passive seismology scenarios. Furthermore, in situations where data quantities are abundant, such as for ambient noise correlations, it remains very difficult to recover pseudo-Green's function symmetry in the ballistic components of the wavefield, let alone in the coda of the correlations. In this study, we use a large network of short period and broadband instruments on Erebus volcano to show that actual Green's function recovery is indeed possible in some cases. We make use of a large database of small impulsive icequakes distributed randomly on the summit plateau and, using fundamental theoretical properties of equipartitioned wavefields and interstation icequake coda correlations, are able to directly derive notoriously difficult quantities such as the bulk elastic mean free path for the volcano, demonstrations of correlation coda symmetry and its dependence on the number of icequakes used, and a theoretically predicted coherent backscattering amplification factor associated with weak localization. We furthermore show that stable equipartition and H^2/V^2 ratios may be consistently observed for icequake coda, and we perform simple depth inversions of these frequency dependent quantities to compare with known structures.

Defocussing characteristics of the ACTS, T1-VSAT Earth terminal antennas

NASA Technical Reports Server (NTRS)

Lambert, Kevin M.; Strickler, Walter M.

1994-01-01

This report describes a study, the purpose of which was to determine the characteristics of two reflector antennas, as the reflector feed is moved away from the focus. The antennas are a 1.2 meter and a 2.44 meter reflector that will be used in the T1-VSAT earth terminals for the Advanced Communications Technology Satellite (ACTS). These terminals have been constructed in such a way that is inconvenient to use attenuators to control the gain of the signal that is directed toward the satellite. Feed defocusing was proposed as a simple, convenient way to achieve the required gain control. The study was performed in two parts. In order to determine the feasibility of the technique, a theoretical analysis was performed to obtain the gain, beamwidth and far-field pattern of the antennas, as a function of feed displacement. An experimental investigation followed in which patterns of the 1.2 meter antenna were obtained through measurement in the NASA Lewis Research Center, Near-Field Antenna Test Facility. Results of the theoretical and experimental investigation are presented for both uplink (30 GHz) and downlink (20 GHz) frequencies.

An experimental investigation of a Mach 3.0 high-speed civil transport at supersonic speeds

NASA Technical Reports Server (NTRS)

Hernandez, Gloria; Covell, Peter F.; Mcgraw, Marvin E., Jr.

1993-01-01

An experimental study was conducted to determine the aerodynamic characteristics of a proposed high speed civil transport. This configuration was designed to cruise at Mach 3.0 and sized to carry 250 passengers for 6500 n.mi. The configuration consists of a highly blended wing body and features a blunt parabolic nose planform, a highly swept inboard wing panel, a moderately swept outboard wing panel, and a curved wingtip. Wind tunnel tests were conducted in the Langley Unitary Plan Wind Tunnel on a 0.0098-scale model. Force, moment, and pressure data were obtained for Mach numbers ranging from 1.6 to 3.6 and at angles of attack ranging from -4 to 10 deg. Extensive flow visualization studies (vapor screen and oil flow) were obtained in the experimental program. Both linear and advanced computational fluid dynamics (CFD) theoretical comparisons are shown to assess the ability to predict forces, moments, and pressures on configurations of this type. In addition, an extrapolation of the wind tunnel data, based on empirical principles, to full-scale conditions is compared with the theoretical aerodynamic predictions.

Studies for the Loss of Atomic and Molecular Species from Io

NASA Technical Reports Server (NTRS)

Combi, Michael R.

1997-01-01

The general objective of this project has been to advance our theoretical understanding of Io's atmosphere and how various atomic and molecular species are lost from this atmosphere and are distributed in the circumplanetary environment of Jupiter. The scientific objectives of the larger collaborative program between AER, Inc., and the University of Michigan have been to undertake theoretical modeling studies to simulate the distributions of the exospheric gases in Io's corona and extended clouds, to investigate the importance of the various physical processes that shape their relative abundances, and with these tools to analyze observations of O, S and Na obtained by four observers: M.A. McGrath of the Space Telescope Science Institute and G.E. Ballester of the University of Michigan who each have obtained Hubble Space Telescope observations of O and S near Io, F. Scherb who continues an effort to obtain 6300 A OI observations as part of the University of Wisconsin Fabry-Perot program, and N.M. Schneider of the University of Colorado who obtained an extensive set of spectral and spatial observations of the Na emission near Io in the D-lines.

Prospects for direct social perception: a multi-theoretical integration to further the science of social cognition

PubMed Central

Wiltshire, Travis J.; Lobato, Emilio J. C.; McConnell, Daniel S.; Fiore, Stephen M.

2015-01-01

In this paper we suggest that differing approaches to the science of social cognition mirror the arguments between radical embodied and traditional approaches to cognition. We contrast the use in social cognition of theoretical inference and mental simulation mechanisms with approaches emphasizing a direct perception of others’ mental states. We build from a recent integrative framework unifying these divergent perspectives through the use of dual-process theory and supporting social neuroscience research. Our elaboration considers two complementary notions of direct perception: one primarily stemming from ecological psychology and the other from enactive cognition theory. We use this as the foundation from which to offer an account of the informational basis for social information and assert a set of research propositions to further the science of social cognition. In doing so, we point out how perception of the minds of others can be supported in some cases by lawful information, supporting direct perception of social affordances and perhaps, mental states, and in other cases by cues that support indirect perceptual inference. Our goal is to extend accounts of social cognition by integrating advances across disciplines to provide a multi-level and multi-theoretic description that can advance this field and offer a means through which to reconcile radical embodied and traditional approaches to cognitive neuroscience. PMID:25709572

Archaeology Hijacked: Addressing the Historical Misappropriations of Maritime and Underwater Archaeology

NASA Astrophysics Data System (ADS)

Gately, Iain; Benjamin, Jonathan

2017-09-01

As a discipline that has grown up in the eyes of the camera, maritime and underwater archaeology has struggled historically to distinguish itself from early misrepresentations of it as adventure-seeking, treasure hunting and underwater salvage as popularized in the 1950s and 1960s. Though many professional archaeologists have successfully moved forward from this history through broader theoretical engagement and the development of the discipline within anthropology, public perception of archaeology under water has not advanced in stride. Central to this issue is the portrayal of underwater archaeology within popular culture and the representational structures from the 1950s and 1960s persistently used to introduce the profession to the public, through the consumption of popular books and especially television. This article explores representations of maritime and underwater archaeology to examine how the discipline has been consumed by the public, both methodologically and theoretically, through media. In order to interrogate this, we first examine maritime and underwater archaeology as a combined sub-discipline of archaeology and consider how it has been defined historically and in contemporary professional practice. Finally, we consider how practitioners can take a proactive approach to portray their work and convey archaeological media to the public. In this respect, we aim to advance the theoretical discussion in a way so as to reduce further cases whereby archaeology is accidentally misappropriated or deliberately hijacked.

Approximate analytical solutions of the pseudospin symmetric Dirac equation for exponential-type potentials

NASA Astrophysics Data System (ADS)

Gately, Iain; Benjamin, Jonathan

2018-04-01

As a discipline that has grown up in the eyes of the camera, maritime and underwater archaeology has struggled historically to distinguish itself from early misrepresentations of it as adventure-seeking, treasure hunting and underwater salvage as popularized in the 1950s and 1960s. Though many professional archaeologists have successfully moved forward from this history through broader theoretical engagement and the development of the discipline within anthropology, public perception of archaeology under water has not advanced in stride. Central to this issue is the portrayal of underwater archaeology within popular culture and the representational structures from the 1950s and 1960s persistently used to introduce the profession to the public, through the consumption of popular books and especially television. This article explores representations of maritime and underwater archaeology to examine how the discipline has been consumed by the public, both methodologically and theoretically, through media. In order to interrogate this, we first examine maritime and underwater archaeology as a combined sub-discipline of archaeology and consider how it has been defined historically and in contemporary professional practice. Finally, we consider how practitioners can take a proactive approach to portray their work and convey archaeological media to the public. In this respect, we aim to advance the theoretical discussion in a way so as to reduce further cases whereby archaeology is accidentally misappropriated or deliberately hijacked.

Education and Training for Sustainable Tourism: Problems, Possibilities and Cautious First Steps.

ERIC Educational Resources Information Center

Gough, Stephen; Scott, William

1999-01-01

Advances a possible theoretical approach to education for sustainable tourism and describes a small-scale research project based on this approach. Seeks to integrate education for sustainable tourism into an established management curriculum using an innovative technique based on the idea of an adaptive concept. (Author/CCM)

Sex Therapy: Advances in Paradigms, Nomenclature, and Treatment

ERIC Educational Resources Information Center

Althof, Stanley

2010-01-01

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

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

Prime, Michael B.; DeWald, Adrian T.; Hill, Michael R.

Forensic engineering - the scientific examination and analysis of failed structures and parts relating to their failure or cause of damage. Real advances in experimental mechanics require innovative theoretical and analytical thinking to go with innovative capabilities. For example, taking full field data (e.g., DIC) and treating it like discrete data (strain gauge) misses a wonderful opportunity.

Child Language Research: Building on the Past, Looking to the Future.

ERIC Educational Resources Information Center

Perera, Katharine

1994-01-01

Outlines descriptive, theoretical, and methodological advances in child language research since the first volume of the "Journal of Child Language" was published. Papers in this volume build on earlier research, point the way to new research avenues, and open new lines of inquiry. (Contains 36 references.) (JP)

Effects of a Math Intervention Program on Math Academic Performance among African American Students

ERIC Educational Resources Information Center

Johnson, Willie F., Jr.

2013-01-01

In the United States, an academic achievement gap has prevented many African American students from advancement and educational empowerment. Guided by Bandura's theoretical belief, which posits a relationship between social factors and an individual's perception, this non-experimental, causal comparative, control treatment group design study…

The Effectiveness of Technology Integration in a Metropolitan Elementary Mathematics Program: Mad Dog Math

ERIC Educational Resources Information Center

Cohen, Miriam

2012-01-01

The outcome of American students' performances during international comparisons consistently scoring inadequately in mathematics exposes the crisis of deficient mathematics achievement thus causing deep concerns. Learners who acquire a strong theoretical foundation in mathematics at the primary level thrived later in more advanced level…

Dual-Retrieval Models and Neurocognitive Impairment

ERIC Educational Resources Information Center

Brainerd, C. J.; Reyna, V. F.; Gomes, C. F. A.; Kenney, A. E.; Gross, C. J.; Taub, E. S.; Spreng, R. N.

2014-01-01

Advances in dual-retrieval models of recall make it possible to use clinical data to test theoretical hypotheses about mild cognitive impairment (MCI) and Alzheimer's dementia (AD), the most common forms of neurocognitive impairment. Hypotheses about the nature of the episodic memory declines in these diseases, about decline versus sparing of…

Sexual Resourcefulness and the Impact of Family, Sex Education, Media and Peers

ERIC Educational Resources Information Center

Kennett, Deborah J.; Humphreys, Terry P.; Schultz, Kristen E.

2012-01-01

Building on a recently developed theoretical model of sexual self-control, 178 undergraduate women completed measures of learned resourcefulness, reasons for consenting to unwanted advances, and sexual self-efficacy--variables consistently shown to be unique predictors of sexual resourcefulness. Additional measures assessed in this investigation…

Cecilia Braslavsky and the New Educational Paradigm

ERIC Educational Resources Information Center

Filmus, Daniel

2005-01-01

This article describes Cecilia Braslavsky's role in the development of theoretical frameworks based on empirical research that, in the stage of restoration of democracy in Latin America, made it possible to advance in the construction of a Latin American socioeducational paradigm. This article discusses some propositions that may systematize the…

Stochastic game theory: for playing games, not just for doing theory.

PubMed

Goeree, J K; Holt, C A

1999-09-14

Recent theoretical advances have dramatically increased the relevance of game theory for predicting human behavior in interactive situations. By relaxing the classical assumptions of perfect rationality and perfect foresight, we obtain much improved explanations of initial decisions, dynamic patterns of learning and adjustment, and equilibrium steady-state distributions.

Sex, Anger and Depression

ERIC Educational Resources Information Center

Simon, Robin W.; Lively, Kathryn

2010-01-01

A social problem that has preoccupied sociologists of gender and mental health is the higher rate of depression found among women. Although a number of hypotheses about this health disparity between men and women have been advanced, none consider the importance of subjectively experienced anger. Drawing on theoretical and empirical insights from…

Revisiting Jürgen Habermas's Notion of Communicative Action and Its Relevance for South African School Governance: Can It Succeed?

ERIC Educational Resources Information Center

Mabovula, Nonceba

2010-01-01

I apply as theoretical framework the Habermassian principles of "communicative action" and "consensus" through deliberation and reasoning. In particular, I focus on "rational" and "argumentative" communication through which school governance stakeholders could advance arguments and counter-arguments. I…

Asian American Acculturation and Enculturation: Construct Clarification and Measurement Consolidation

ERIC Educational Resources Information Center

Zhang, Shengying; Moradi, Bonnie

2013-01-01

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

Psychologic-Pedagogical Conditions for Prevention of Suicidal Tendencies among Teenagers

ERIC Educational Resources Information Center

Abil, Yerkin A.; Kim, Natalia P.; Baymuhambetova, Botagoz Sh.; Mamiyev, Nurlan B.; Li, Yelena D.; Shumeyko, Tatyana S.

2016-01-01

Aim of research: to develop complex of psychology-pedagogical conditions, directed on prevention of suicidal tendencies among teenagers. On analysis basis of scientific literature authors disclose main causes of suicidal behavior in adolescence. To confirm science veracity of advanced theoretic assumptions, describes experiment, conducted on basis…

Advancing Measurement of Work and Family Domain Boundary Characteristics

ERIC Educational Resources Information Center

Matthews, Russell A.; Barnes-Farrell, Janet L.; Bulger, Carrie A.

2010-01-01

Recent research offers promising theoretical frameworks for thinking about the work-family interface in terms of the boundaries individuals develop around work and family. However, measures for important constructs proposed by these theories are needed. Using two independent samples, we report on the refinement of existing "boundary flexibility"…

Acting White: A Critical Review

ERIC Educational Resources Information Center

Sohn, Kitae

2011-01-01

The hypothesis of acting White has been heatedly debated and influential over the last 20 years or so in explaining the Black-White test score gap. Recently, economists have joined the debate and started providing new theoretical and empirical analyses of the phenomenon. This paper critically reviews the arguments that have been advanced to…

77 FR 59998 - Self-Regulatory Organizations; The Options Clearing Corporation; Advance Notice Relating to the...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-01

... System for Theoretical Analysis and Numerical Simulations (``STANS''). STANS calculates margin with...'' simulations designed to measure the additional asset value required in any portfolio to eliminate an... Commission process and review your comments more efficiently, please use only one method. The Commission will...

Learning Physical Domains: Toward a Theoretical Framework.

DTIC Science & Technology

1986-12-01

advanced ids o the iaime doinain in containing more information, especially perceptual " ’It. iho lI b1 rwt... tI hat. psychboigists by no means...Acquisitions Dr Kenneth D Forbus 4833 Rugby Avenue University of Illinois Dr Robert Glaser Bethesda, MD 20014 Department of Computer Science Learning

The Effects of Passage of Time on Alumni Recall of "Student Experience"

ERIC Educational Resources Information Center

Koenig-Lewis, Nicole; Asaad, Yousra; Palmer, Adrian; Petersone, Elina

2016-01-01

"Student experience" has become a popular term with higher education managers but is theoretically under-developed. This paper conceptualises student experience as a construction from memory and advances previous discussion within the higher education sector by distinguishing between recalled academic and social experience. The results…

Teachers' Views of Their Assessment Practice

ERIC Educational Resources Information Center

Atjonen, Päivi

2014-01-01

The main aim of this research was to analyse teachers' views of pupil assessment. The theoretical framework was based on existing literature on advances and challenges of pupil assessment in regard to support for learning, fairness, educational partnership, feedback, and favourable methods. The data were gathered by means of a questionnaire…

Advanced Quantitative Measurement Methodology in Physics Education Research

ERIC Educational Resources Information Center

Wang, Jing

2009-01-01

The ultimate goal of physics education research (PER) is to develop a theoretical framework to understand and improve the learning process. In this journey of discovery, assessment serves as our headlamp and alpenstock. It sometimes detects signals in student mental structures, and sometimes presents the difference between expert understanding and…

Bibliography of Soviet Laser Developments, September-October 1987

DTIC Science & Technology

1988-10-01

Lasers , Gas Lasers , Chemical Lasers , Laser Components Nonlinear Optics, Spectroscopy of Laser Materials, Ultrashort Pulse Generation, Laser ...optics; spectroscopy of laser materials; ultrashort pulse generation; crystal growing; theoretical aspects of advanced lasers ; and general laser theory...focusing ....................... 26 6. Acoustic Interaction ................ 26 G. Spectroscopy of Laser Materials ......... 28 H.

New Thinking in School Chemistry.

ERIC Educational Resources Information Center

Organisation for Economic Cooperation and Development, Paris (France).

This report contains the text of addresses given at a seminar on the status and development of the teaching of secondary school chemistry held in 1960 by the Organization for European Economic Development (now the Organization for Economic Cooperation and Development). The speakers considered advances in theoretical chemistry since 1900, the…

Writing for Professional Publication: Three Road Signs for Writing Success

ERIC Educational Resources Information Center

Buttery, Thomas J.

2010-01-01

In the first edition of Writing for Publication: An Organizational Paradigm (Buttery, 2010), I recommend a model for organizing theoretical articles. The process includes seven components: title, introduction, outline/advanced organizer, headings, transitions, summary and references. This article will focus on the writing process. The strands of…

Identifiability Of Systems With Modeling Errors

NASA Technical Reports Server (NTRS)

Hadaegh, Yadolah " fred" ; Bekey, George A.

1988-01-01

Advances in theory of modeling errors reported. Recent paper on errors in mathematical models of deterministic linear or weakly nonlinear systems. Extends theoretical work described in NPO-16661 and NPO-16785. Presents concrete way of accounting for difference in structure between mathematical model and physical process or system that it represents.

Determination of absolute configuration of natural products: theoretical calculation of electronic circular dichroism as a tool

USDA-ARS?s Scientific Manuscript database

Determination of absolute configuration (AC) is one of the most challenging features in the structure elucidation of chiral natural products, especially those with complex structures. With revolutionary advancements in the area of quantum chemical calculations of chiroptical spectroscopy over the pa...

The Anxiety of Affluence

ERIC Educational Resources Information Center

Sensenig, Victor J.

2012-01-01

This review essay of "Producing Success: The Culture of Personal Advancement in an American High School" by Peter Demerath focuses on the theory of cultural dysfunction. It places the book within a theoretical tradition of social reproduction and status attainment using other ethnographies by Varenne and McDermott, Lareau, and Howard. It argues…

"Movement as Motive": Self Definition and Social Advocacy in Social Movement Autobiographies.

ERIC Educational Resources Information Center

Griffin, Charles J. G.

2000-01-01

Contributes to scholarship advancing the understanding of human communication by elaborating a theoretical framework for understanding the synthesis of self-definition and social advocacy in social movement autobiographies. Uses insights from Kenneth Burke and posits that in a rhetorically effective movement autobiography, form enables the…

Regulation of Iron Acquisition Responses in Plant Roots by a Transcription Factor

ERIC Educational Resources Information Center

Bauer, Petra

2016-01-01

The presented research hypothesis-driven laboratory exercise teaches advanced undergraduate students state of the art methods and thinking in an integrated molecular physiology context. Students understand the theoretical background of iron acquisition in the model plant "Arabidopsis thaliana." They design a flowchart summarizing the key…

Restorative Justice: Pedagogy, Praxis, and Discipline

ERIC Educational Resources Information Center

Morrison, Brenda E.; Vaandering, Dorothy

2012-01-01

In the ongoing effort of designing school contexts in support of proactive discipline, a range of practices and theoretical frameworks have been advanced, from behaviorist approaches to social and emotional learning. This article describes the theory and practice of restorative justice with the aim of defining this distinctive paradigm, in…

Understanding Clinical Anger and Violence: The Anger Avoidance Model

ERIC Educational Resources Information Center

Gardner, Frank L.; Moore, Zella E.

2008-01-01

Although anger is a primary emotion and holds clear functional necessities, the presence of anger and its behavioral manifestations of aggression/violence can have serious emotional, health, and social consequences. Despite such consequences, the construct of clinical anger has to date suffered from few theoretical and treatment advancements and…

Inkjet printing for biosensor fabrication: combining chemistry and technology for advanced manufacturing.

PubMed

Li, Jia; Rossignol, Fabrice; Macdonald, Joanne

2015-06-21

Inkjet printing is emerging at the forefront of biosensor fabrication technologies. Parallel advances in both ink chemistry and printers have led to a biosensor manufacturing approach that is simple, rapid, flexible, high resolution, low cost, efficient for mass production, and extends the capabilities of devices beyond other manufacturing technologies. Here we review for the first time the factors behind successful inkjet biosensor fabrication, including printers, inks, patterning methods, and matrix types. We discuss technical considerations that are important when moving beyond theoretical knowledge to practical implementation. We also highlight significant advances in biosensor functionality that have been realised through inkjet printing. Finally, we consider future possibilities for biosensors enabled by this novel combination of chemistry and technology.

Optics of high-performance electron microscopes*

PubMed Central

Rose, H H

2008-01-01

During recent years, the theory of charged particle optics together with advances in fabrication tolerances and experimental techniques has lead to very significant advances in high-performance electron microscopes. Here, we will describe which theoretical tools, inventions and designs have driven this development. We cover the basic theory of higher-order electron optics and of image formation in electron microscopes. This leads to a description of different methods to correct aberrations by multipole fields and to a discussion of the most advanced design that take advantage of these techniques. The theory of electron mirrors is developed and it is shown how this can be used to correct aberrations and to design energy filters. Finally, different types of energy filters are described. PMID:27877933

Laparoscopic versus open-component separation: a comparative analysis in a porcine model.

PubMed

Rosen, Michael J; Williams, Christina; Jin, Judy; McGee, Michael F; Schomisch, Steve; Marks, Jeffrey; Ponsky, Jeffrey

2007-09-01

The ideal surgical treatment for complicated ventral hernias remains elusive. Traditional component separation provides local advancement of native tissue for tension-free closure without prosthetic materials. This technique requires an extensive subcutaneous dissection with division of perforating vessels predisposing to skin-flap necrosis and complicated wound infections. A minimally invasive component separation may decrease wound complication rates; however, the adequacy of the myofascial advancement has not been studied. Five 25-kg pigs underwent bilateral laparoscopic component separation. A 10-mm incision was made lateral to the rectus abdominus muscle. The external oblique fascia was incised, and a dissecting balloon was inflated between the internal and external oblique muscles. Two additional ports were placed in the intermuscular space. The external oblique was incised from the costal margin to the inguinal ligament. The maximal abdominal wall advancement was recorded. A formal open-component separation was performed and maximal advancement 5 cm superior and 5 cm inferior to the umbilicus was recorded for comparison. Groups were compared using standard statistical analysis. The laparoscopic component separation was completed successfully in all animals, with a mean of 22 min/side. Laparoscopic component separation yielded 3.9 cm (SD 1.1) of fascial advancement above the umbilicus, whereas 4.4 cm (1.2) was obtained after open release (P = .24). Below the umbilicus, laparoscopic release achieved 5.0 cm (1.0) of advancement, whereas 5.8 cm (1.2) was gained after open release (P = .13). The minimally invasive component separation achieved an average of 86% of the myofascial advancement compared with a formal open release. The laparoscopic approach does not require extensive subcutaneous dissection and might theoretically result in a decreased incidence or decreased complexity of postoperative wound infections or skin-flap necrosis. Based on our preliminary data in this porcine model, further comparative studies of laparoscopic versus open component separation in complex ventral hernia repair is warranted to evaluate postoperative morbidity and long-term hernia recurrence rates.

Theory of the Origin, Evolution, and Nature of Life

PubMed Central

Andrulis, Erik D.

2011-01-01

Life is an inordinately complex unsolved puzzle. Despite significant theoretical progress, experimental anomalies, paradoxes, and enigmas have revealed paradigmatic limitations. Thus, the advancement of scientific understanding requires new models that resolve fundamental problems. Here, I present a theoretical framework that economically fits evidence accumulated from examinations of life. This theory is based upon a straightforward and non-mathematical core model and proposes unique yet empirically consistent explanations for major phenomena including, but not limited to, quantum gravity, phase transitions of water, why living systems are predominantly CHNOPS (carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur), homochirality of sugars and amino acids, homeoviscous adaptation, triplet code, and DNA mutations. The theoretical framework unifies the macrocosmic and microcosmic realms, validates predicted laws of nature, and solves the puzzle of the origin and evolution of cellular life in the universe. PMID:25382118

Autonomous space processor for orbital debris

NASA Technical Reports Server (NTRS)

Ramohalli, Kumar; Campbell, David; Brockman, Jeff P.; Carter, Bruce; Donelson, Leslie; John, Lawrence E.; Marine, Micky C.; Rodina, Dan D.

1989-01-01

This work continues to develop advanced designs toward the ultimate goal of a GETAWAY SPECIAL to demonstrate economical removal of orbital debris utilizing local resources in orbit. The fundamental technical feasibility was demonstrated last year through theoretical calculations, quantitative computer animation, a solar focal point cutter, a robotic arm design and a subscale model. During this reporting period, several improvements are made in the solar cutter, such as auto track capabilities, better quality reflectors and a more versatile framework. The major advance has been in the design, fabrication and working demonstration of a ROBOTIC ARM that has several degrees of freedom. The functions were specifically tailored for the orbital debris handling. These advances are discussed here. Also a small fraction of the resources were allocated towards research in flame augmentation in SCRAMJETS for the NASP. Here, the fundamental advance was the attainment of Mach numbers up to 0.6 in the flame zone and a vastly improved injection system; the current work is expected to achieve supersonic combustion in the laboratory and an advanced monitoring system.

Ethnocultural women's experiences of breast cancer: a qualitative meta-study.

PubMed

Howard, A Fuchsia; Balneaves, Lynda G; Bottorff, Joan L

2007-01-01

A growing number of studies have been conducted that explore the breast cancer experiences of women from diverse ethnocultural groups. To advance knowledge and provide a foundation for future research, a synthesis was conducted of 15 qualitative research studies focusing on women from ethnocultural groups diagnosed with breast cancer. A qualitative meta-study approach was used that included analysis of the theoretical orientations and methodological approaches underlying the research, and an interpretive synthesis of research findings. Ethnocultural groups represented in the studies included Asian American, Aboriginal, Hispanic, and African American women. The synthesis revealed diverse experiences within and among these ethnocultural groups represented in 5 major themes: (a) the "othered" experience of a breast cancer diagnosis, (b) the treatment experience as "other," (c) losses associated with breast cancer, (d) the family context of breast cancer experiences, and (e) coping with cancer through spirituality and community involvement. The integration of findings from the 15 studies also revealed how methodological and theoretical approaches to conducting this research influenced understandings of the experiences of breast cancer. Further experiential breast cancer research with ethnocultural groups is needed, as well as the use of research methods that illuminate the ways that ethnicity, class, age, and gender relations are played out in healthcare settings.

A theory-based approach to nursing shared governance.

PubMed

Joseph, M Lindell; Bogue, Richard J

2016-01-01

The discipline of nursing uses a general definition of shared governance. The discipline's lack of a specified theory with precepts and propositions contributes to persistent barriers in progress toward building evidence-based knowledge through systematic study. The purposes of this article were to describe the development and elements of a program theory approach for nursing shared governance implementation and to recommend further testing. Five studies using multiple methods are described using a structured framework. The studies led to the use of Lipsey's method of theory development for program implementation to develop a theory for shared governance for nursing. Nine competencies were verified to define nursing practice council effectiveness. Other findings reveal that nurse empowerment results from alignment between the competencies of self- directed work teams and the competencies of organizational leaders. Implementation of GEMS theory based nursing shared governance can advance goals at the individual, unit, department, and organization level. Advancing professional nursing practice requires that nursing concepts are systematically studied and then formalized for implementation. This article describes the development of a theoretical foundation for the systematic study and implementation of nursing shared governance. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

Nuclear fission: a review of experimental advances and phenomenology

NASA Astrophysics Data System (ADS)

Andreyev, A. N.; Nishio, K.; Schmidt, K.-H.

2018-01-01

In the last two decades, through technological, experimental and theoretical advances, the situation in experimental fission studies has changed dramatically. With the use of advanced production and detection techniques both much more detailed and precise information can now be obtained for the traditional regions of fission research and, crucially, new regions of nuclei have become routinely accessible for fission studies. This work first of all reviews the recent developments in experimental fission techniques, in particular the resurgence of transfer-induced fission reactions with light and heavy ions, the emerging use of inverse-kinematic approaches, both at Coulomb and relativistic energies, and of fission studies with radioactive beams. The emphasis on the fission-fragment mass and charge distributions will be made in this work, though some of the other fission observables, such as prompt neutron and γ-ray emission will also be reviewed. A particular attention will be given to the low-energy fission in the so far scarcely explored nuclei in the very neutron-deficient lead region. They recently became the focus for several complementary experimental studies, such as β-delayed fission with radioactive beams at ISOLDE(CERN), Coulex-induced fission of relativistic secondary beams at FRS(GSI), and several prompt fusion–fission studies. The synergy of these approaches allows a unique insight in the new region of asymmetric fission around {\\hspace{0pt}}180 Hg, recently discovered at ISOLDE. Recent extensive theoretical efforts in this region will also be outlined. The unprecedented high-quality data for fission fragments, completely identified in Z and A, by means of reactions in inverse kinematics at FRS(GSI) and VAMOS(GANIL) will be also reviewed. These experiments explored an extended range of mercury-to-californium elements, spanning from the neutron-deficient to neutron-rich nuclides, and covering both asymmetric, symmetric and transitional fission regions. Some aspects of heavy-ion induced fusion–fission and quasifission reactions will be also discussed, which reveal their dynamical features, such as the fission time scale. The crucial role of the multi-chance fission, probed by means of multinucleon-transfer induced fission reactions, will be highlighted. The review will conclude with the discussion of the new experimental fission facilities which are presently being brought into operation, along with promising ‘next-generation’ fission approaches, which might become available within the next decade.

Enlarging the scope: grasping brain complexity

PubMed Central

Tognoli, Emmanuelle; Kelso, J. A. Scott

2014-01-01

To further advance our understanding of the brain, new concepts and theories are needed. In particular, the ability of the brain to create information flows must be reconciled with its propensity for synchronization and mass action. The theoretical and empirical framework of Coordination Dynamics, a key aspect of which is metastability, are presented as a starting point to study the interplay of integrative and segregative tendencies that are expressed in space and time during the normal course of brain and behavioral function. Some recent shifts in perspective are emphasized, that may ultimately lead to a better understanding of brain complexity. PMID:25009476

Preface: Special Topic on Single-Molecule Biophysics

NASA Astrophysics Data System (ADS)

Makarov, Dmitrii E.; Schuler, Benjamin

2018-03-01

Single-molecule measurements are now almost routinely used to study biological systems and processes. The scope of this special topic emphasizes the physics side of single-molecule observations, with the goal of highlighting new developments in physical techniques as well as conceptual insights that single-molecule measurements bring to biophysics. This issue also comprises recent advances in theoretical physical models of single-molecule phenomena, interpretation of single-molecule signals, and fundamental areas of statistical mechanics that are related to single-molecule observations. A particular goal is to illustrate the increasing synergy between theory, simulation, and experiment in single-molecule biophysics.

Pseudomorphic Semiconducting Heterostructures from Combinations of AlN, GaN and Selected SiC Polytypes: Theoretical Advancement and its Coordination with Experimental Studies of Nucleation, Growth, Characterization and Device Development

DTIC Science & Technology

1994-06-01

simultaneously expluiting the favorable characteristics of these materials include the thin film deposition of both pseudomorphic beterostructure and alloys ...diagram proposed by Zangvil and Ruh [10] shows a flat miscibility gap at =1900*C between -20 and 80 wt % AIN. Above this temperature, a 2H solid solution...was reported from >20 wt % AIN. For .20 wt % AIN, 8 I I solutions and two phase mixtures of 6H, 4H, and 2H were observed. Thin film solid solutions

Molten Salts and Isotope Separation

NASA Astrophysics Data System (ADS)

Lantelme, Frédéric

2013-02-01

The work on molten salts and isotope separation performed over the years at Université Pierre et Marie Curie and at Collège de France is critically reviewed. This research, closely related to A. Klemm's pioneering contributions, leads among other things to the discovery of the effect now called the `Chemla effect', after the late Professor Marius Chemla. These studies of ionic motions in melts, and liquids in general, have greatly benefitted from recent advances in molecular simulations. Some recent results of such simulations - molecular dynamics (MD) and Brownian dynamics (BD) - as well as of related theoretical work are discussed.

Amorphous photonic crystals with only short-range order.

PubMed

Shi, Lei; Zhang, Yafeng; Dong, Biqin; Zhan, Tianrong; Liu, Xiaohan; Zi, Jian

2013-10-04

Distinct from conventional photonic crystals with both short- and long-range order, amorphous photonic crystals that possess only short-range order show interesting optical responses owing to their unique structural features. Amorphous photonic crystals exhibit unique light scattering and transport, which lead to a variety of interesting phenomena such as isotropic photonic bandgaps or pseudogaps, noniridescent structural colors, and light localization. Recent experimental and theoretical advances in the study of amorphous photonic crystals are summarized, focusing on their unique optical properties, artificial fabrication, bionspiration, and potential applications. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Proceedings of the NATO-Advanced Study Institute on Computer Aided Analysis of Rigid and Flexible Mechanical Systems Held in Troia, Portugal on 27 Jun-9 Jul, 1993. Volume 2. Contributed Papers

DTIC Science & Technology

1993-07-09

Calculate Oil and solve iteratively equation (18) for q and (l)-(S) forex . 4, Solve the velocity problemn through equation (19) to calculate q and (6)-(10) to...object.oriented models for the database to store the system information f1l. Using OOP on the formalism level is more difficult and a current field of...Multidimensional Physical Systems: Graph-theoretic Modeling, Systems and Cybernetics, vol 21 (1992), 5 .9-71 JV A RELATIONAL DATABASE FOR GENERAL

Tunable terahertz optical properties of graphene in dc electric fields

NASA Astrophysics Data System (ADS)

Dong, H. M.; Huang, F.; Xu, W.

2018-03-01

We develop a simple theoretical approach to investigate terahertz (THz) optical properties of monolayer graphene in the presence of an external dc electric field. The analytical results for optical coefficients such as the absorptance and reflectivity are obtained self-consistently on the basis of a diagrammatic self-consistent field theory and a Boltzmann equilibrium equation. It is found that the optical refractive index, reflectivity and conductivity can be effectively tuned by not only a gate voltage but also a driving dc electric field. This study is relevant to the applications of graphene as advanced THz optoelectronic devices.

Perinatal Bereavement: A Principle-based Concept Analysis

PubMed Central

FENSTERMACHER, Kimberly; HUPCEY, Judith E.

2013-01-01

Aim This paper is a report of an analysis of the concept of perinatal bereavement. Background The concept of perinatal bereavement emerged in the scientific literature during the 1970s. Perinatal bereavement is a practice based concept, although it is not well defined in the scientific literature and is often intermingled with the concepts of mourning and grief. Design Concept Analysis. Data Sources Using the term ‘perinatal bereavement’ and limits of only English and human, Pub Med and CINAHL were searched to yield 278 available references dating from 1974 – 2011. Articles specific to the experience of perinatal bereavement were reviewed. The final data set was 143 articles. Review Methods The methods of principle-based concept analysis were used. Results reveal conceptual components (antecedents, attributes and outcomes) which are delineated to create a theoretical definition of perinatal bereavement. Results The concept is epistemologically immature, with few explicit definitions to describe the phenomenon. Inconsistency in conceptual meaning threatens the construct validity of measurement tools for perinatal bereavement and contributes to incongruent theoretical definitions. This has implications for both nursing science (how the concept is studied and theoretically integrated) and clinical practice (timing and delivery of support interventions). Conclusions Perinatal bereavement is a multifaceted global phenomenon that follows perinatal loss. Lack of conceptual clarity and lack of a clearly articulated conceptual definition impede the synthesis and translation of research findings into practice. A theoretical definition of perinatal bereavement is offered as a platform for researchers to advance the concept through research and theory development. PMID:23458030

Quantitative Evaluation of Performance in Interventional Neuroradiology: An Integrated Curriculum Featuring Theoretical and Practical Challenges.

PubMed

Ernst, Marielle; Kriston, Levente; Romero, Javier M; Frölich, Andreas M; Jansen, Olav; Fiehler, Jens; Buhk, Jan-Hendrik

2016-01-01

We sought to develop a standardized curriculum capable of assessing key competencies in Interventional Neuroradiology by the use of models and simulators in an objective, quantitative, and efficient way. In this evaluation we analyzed the associations between the practical experience, theoretical knowledge, and the skills lab performance of interventionalists. We evaluated the endovascular skills of 26 participants of the Advanced Course in Endovascular Interventional Neuroradiology of the European Society of Neuroradiology with a set of three tasks (aneurysm coiling and thrombectomy in a virtual simulator and placement of an intra-aneurysmal flow disruptor in a flow model). Practical experience was assessed by a survey. Participants completed a written and oral examination to evaluate theoretical knowledge. Bivariate and multivariate analyses were performed. In multivariate analysis knowledge of materials and techniques in Interventional Neuroradiology was moderately associated with skills in aneurysm coiling and thrombectomy. Experience in mechanical thrombectomy was moderately associated with thrombectomy skills, while age was negatively associated with thrombectomy skills. We found no significant association between age, sex, or work experience and skills in aneurysm coiling. Our study gives an example of how an integrated curriculum for reasonable and cost-effective assessment of key competences of an interventional neuroradiologist could look. In addition to traditional assessment of theoretical knowledge practical skills are measured by the use of endovascular simulators yielding objective, quantitative, and constructive data for the evaluation of the current performance status of participants as well as the evolution of their technical competency over time.