Exploring oxidative ageing behaviour of hydrocarbons using ab initio molecular dynamics analysis

NASA Astrophysics Data System (ADS)

Pan, Tongyan; Cheng, Cheng

2016-06-01

With a proper approximate solution to the Schrödinger Equation of a multi-electron system, the method of ab initio molecular dynamics (AIMD) performs first-principles molecular dynamics analysis without pre-defining interatomic potentials as are mandatory in traditional molecular dynamics analyses. The objective of this study is to determine the oxidative-ageing pathway of petroleum asphalt as a typical hydrocarbon system, using the AIMD method. This objective was accomplished in three steps, including (1) identifying a group of representative asphalt molecules to model, (2) determining an atomistic modelling method that can effectively simulate the production of critical functional groups in oxidative ageing of hydrocarbons and (3) evaluating the oxidative-ageing pathway of a hydrocarbon system. The determination of oxidative-ageing pathway of hydrocarbons was done by tracking the generations of critical functional groups in the course of oxidative ageing. The chemical elements of carbon, nitrogen and sulphur all experience oxidative reactions, producing polarised functional groups such as ketones, aldehydes or carboxylic acids, pyrrolic groups and sulphoxides. The electrostatic forces of the polarised groups generated in oxidation are responsible for the behaviour of aged hydrocarbons. The developed AIMD model can be used for modelling the ageing of generic hydrocarbon polymers and developing antioxidants without running expensive experiments.

Dynamic Assessment of Writing: The Impact of Implicit/Explicit Mediations on L2 Learners' Internalization of Writing Skills and Strategies

ERIC Educational Resources Information Center

Alavi, Sayyed Mohammad; Taghizadeh, Mahboubeh

2014-01-01

Dynamic assessment is a procedure in which development is simultaneously assessed and improved with regard to the individual's or group's Zone of Proximal Development (ZPD; Lantolf & Poehner, 2004). This study aimed to follow dynamic assessment and investigate the impact of three types of implicit and explicit feedback on the essay writing of…

Surfacing the life phases of a mental health support group.

PubMed

Mohr, Wanda K

2004-01-01

Support groups have increased rapidly in number and become a viable alternative to formal treatment in the United States. However, little is known regarding how mental health advocacy or support groups start and develop, or about challenges that can threaten their survival. In this 2 1/2-year ethnography, the author studied the culture of a developing family support program associated with a system of care. Several phases emerged, reflecting an organizational dynamic. The group dynamics and response to challenges have implications for organizers and parent organizations about the need for technical assistance necessary for survival of the group. Participant observation and immersion in the culture of such groups can provide a deeper understanding of the ideologies and values around which they organize and the kinds of tensions that members can experience during the group's cycle.

Contents of chemical elements in stomach during prenatal development: different age-dependent dynamical changes and their significance

PubMed Central

Hou, Shao-Fan; Li, Hai-Rong; Wang, Li-Zhen; Li, De-Zhu; Yang, Lin-Sheng; Li, Chong-Zheng

2003-01-01

AIM: To observe dynamic of different chemical elements in stomach tissue during fetal development. METHODS: To determine contents of the 21 chemical elements in each stomach samples from fetus aging four to ten months. The content values were compared to those from adult tissue samples, and the values for each month group were also analyzed for dynamic changes. RESULTS: Three representations were found regarding the relationship between contents of the elements and ages of the fetus, including the positive correlative (K), reversely correlative (Na, Ca, P, Al, Cu, Zn, Fe, Mn, Cr, Sr, Li, Cd, Ba, Se) and irrelevant groups (Mg, Co, Ni, V, Pb, Ti). CONCLUSION: The chemical elements’ contents in stomach tissues were found to change dynamically with the stomach weights. The age-dependent representations for different chemical elements during the prenatal development may be of some significance for assessing development of fetal stomach and some chemical elements. The data may be helpful for the nutritional balance of fetus and mothers during prenatal development and even the perinatal stages. PMID:12717857

Dynamism in Electronic Performance Support Systems.

ERIC Educational Resources Information Center

Laffey, James

1995-01-01

Describes a model for dynamic electronic performance support systems based on NNAble, a system developed by the training group at Apple Computer. Principles for designing dynamic performance support are discussed, including a systems approach, performer-centered design, awareness of situated cognition, organizational memory, and technology use.…

Improving basic math skills through integrated dynamic representation strategies.

PubMed

González-Castro, Paloma; Cueli, Marisol; Cabeza, Lourdes; Álvarez-García, David; Rodríguez, Celestino

2014-01-01

In this paper, we analyze the effectiveness of the Integrated Dynamic Representation strategy (IDR) to develop basic math skills. The study involved 72 students, aged between 6 and 8 years. We compared the development of informal basic skills (numbers, comparison, informal calculation, and informal concepts) and formal (conventionalisms, number facts, formal calculus, and formal concepts) in an experimental group (n = 35) where we applied the IDR strategy and in a Control group (n = 37) in order to identify the impact of the procedure. The experimental group improved significantly in all variables except for number facts and formal calculus. It can therefore be concluded that IDR favors the development of the skills more closely related to applied mathematics than those related to automatic mathematics and mental arithmetic.

Methodology Development of a Gas-Liquid Dynamic Flow Regime Transition Model

NASA Astrophysics Data System (ADS)

Doup, Benjamin Casey

Current reactor safety analysis codes, such as RELAP5, TRACE, and CATHARE, use flow regime maps or flow regime transition criteria that were developed for static fully-developed two-phase flows to choose interfacial transfer models that are necessary to solve the two-fluid model. The flow regime is therefore difficult to identify near the flow regime transitions, in developing two-phase flows, and in transient two-phase flows. Interfacial area transport equations were developed to more accurately predict the dynamic nature of two-phase flows. However, other model coefficients are still flow regime dependent. Therefore, an accurate prediction of the flow regime is still important. In the current work, the methodology for the development of a dynamic flow regime transition model that uses the void fraction and interfacial area concentration obtained by solving three-field the two-fluid model and two-group interfacial area transport equation is investigated. To develop this model, detailed local experimental data are obtained, the two-group interfacial area transport equations are revised, and a dynamic flow regime transition model is evaluated using a computational fluid dynamics model. Local experimental data is acquired for 63 different flow conditions in bubbly, cap-bubbly, slug, and churn-turbulent flow regimes. The measured parameters are the group-1 and group-2 bubble number frequency, void fraction, interfacial area concentration, and interfacial bubble velocities. The measurements are benchmarked by comparing the prediction of the superficial gas velocities, determined using the local measurements with those determined from volumetric flow rate measurements and the agreement is generally within +/-20%. The repeatability four-sensor probe construction process is within +/-10%. The repeatability of the measurement process is within +/-7%. The symmetry of the test section is examined and the average agreement is within +/-5.3% at z/D = 10 and +/-3.4% at z/D = 32. Revised source/sink terms for the two-group interfacial area transport equations are derived and fit to area-averaged experimental data to determine new model coefficients. The average agreement between this model and the experiment data for the void fraction and interfacial area concentration is 10.6% and 15.7%, respectively. This revised two-group interfacial area transport equation and the three-field two-fluid model are used to solve for the group-1 and group-2 interfacial area concentration and void fraction. These values and a dynamic flow regime transition model are used to classify the flow regimes. The flow regimes determined using this model are compared with the flow regimes based on the experimental data and on a flow regime map using Mishima and Ishii's (1984) transition criteria. The dynamic flow regime transition model is shown to predict the flow regimes dynamically and has improved the prediction of the flow regime over that using a flow regime map. Safety codes often employ the one-dimensional two-fluid model to model two-phase flows. The area-averaged relative velocity correlation necessary to close this model is derived from the drift flux model. The effects of the necessary assumptions used to derive this correlation are investigated using local measurements and these effects are found to have a limited impact on the prediction of the area-averaged relative velocity.

Impaired social brain network for processing dynamic facial expressions in autism spectrum disorders.

PubMed

Sato, Wataru; Toichi, Motomi; Uono, Shota; Kochiyama, Takanori

2012-08-13

Impairment of social interaction via facial expressions represents a core clinical feature of autism spectrum disorders (ASD). However, the neural correlates of this dysfunction remain unidentified. Because this dysfunction is manifested in real-life situations, we hypothesized that the observation of dynamic, compared with static, facial expressions would reveal abnormal brain functioning in individuals with ASD.We presented dynamic and static facial expressions of fear and happiness to individuals with high-functioning ASD and to age- and sex-matched typically developing controls and recorded their brain activities using functional magnetic resonance imaging (fMRI). Regional analysis revealed reduced activation of several brain regions in the ASD group compared with controls in response to dynamic versus static facial expressions, including the middle temporal gyrus (MTG), fusiform gyrus, amygdala, medial prefrontal cortex, and inferior frontal gyrus (IFG). Dynamic causal modeling analyses revealed that bi-directional effective connectivity involving the primary visual cortex-MTG-IFG circuit was enhanced in response to dynamic as compared with static facial expressions in the control group. Group comparisons revealed that all these modulatory effects were weaker in the ASD group than in the control group. These results suggest that weak activity and connectivity of the social brain network underlie the impairment in social interaction involving dynamic facial expressions in individuals with ASD.

"Stop and Go": In Search of New Ecology and Dynamics in Group Counselling for Employees in Transition

ERIC Educational Resources Information Center

Keskinen, Anita; Spangar, Timo

2013-01-01

"Stop and Go" (SG) is a group counselling concept developed for employees in transition. The SG approach has its main roots in relational psychology. This article explores the ecology and the dynamics of the SG process including the simultaneous presence of societal and social ('meso') factors, as well as the individual…

Triple grouping and period-three oscillations in minority-game dynamics.

PubMed

Dong, Jia-Qi; Huang, Zi-Gang; Huang, Liang; Lai, Ying-Cheng

2014-12-01

Dynamical systems based on the minority game (MG) have been a paradigm for gaining significant insights into a variety of social and biological behaviors. Recently, a grouping phenomenon has been unveiled in MG systems of multiple resources (strategies) in which the strategies spontaneously break into an even number of groups, each exhibiting an identical oscillation pattern in the attendance of game players. Here we report our finding of spontaneous breakup of resources into three groups, each exhibiting period-three oscillations. An analysis is developed to understand the emergence of the striking phenomenon of triple grouping and period-three oscillations. In the presence of random disturbances, the triple-group/period-three state becomes transient, and we obtain explicit formula for the average transient lifetime using two methods of approximation. Our finding indicates that, period-three oscillation, regarded as one of the most fundamental behaviors in smooth nonlinear dynamical systems, can also occur in much more complex, evolutionary-game dynamical systems. Our result also provides a plausible insight for the occurrence of triple grouping observed, for example, in the U.S. housing market.

Context and group dynamics in a CBPR-developed HIV prevention intervention

PubMed Central

Dickson-Gomez, Julia; Corbett, A. Michelle; Bodnar, Gloria; Zuniga, Maria Ofelia; Guevara, Carmen Eugenia; Rodriguez, Karla; Navas, Verónica

2016-01-01

This paper will explore in detail the effects of context and group dynamics on the development of a multi-level community-based HIV prevention intervention for crack cocaine users in the San Salvador Metropolitan Area, El Salvador. Community partners included residents from marginal communities, service providers from the historic center of San Salvador and research staff from a non-profit organization. The community contexts from which partners came varied considerably and affected structural group dynamics, i.e. who was identified as community partners, their research and organizational capacity, and their ability to represent their communities, with participants from marginal communities most likely to hold community leadership positions and be residents, and those from the center of San Salvador most likely to work in religious organizations dedicated to HIV prevention or feeding indigent drug users. These differences also affected the intervention priorities of different partners. The context of communities changed over time, particularly levels of violence, and affected group dynamics and the intervention developed. Finally, strategies were needed to elicit input from stakeholders under-represented in the community advisory board, in particular active crack users, in order to check the feasibility of the proposed intervention and revise it as necessary. Because El Salvador is a very different context than that in which most CBPR studies have been conducted, our results reveal important contextual factors and their effects on partnerships not often considered in the literature. PMID:25070835

How Can Social Psychology and Group Dynamics Assist in Curriculum Development?

ERIC Educational Resources Information Center

Chin, Jeffrey; May, Matthew; Sullivan-Chin, Honora; Woodrick, Kaylyn

2014-01-01

This article discusses some of the challenges departments face as they embark on curriculum development. The interpersonal dynamics of a department are often the first and most difficult obstacle to overcome but are often overlooked. The author suggests some strategies for how to address these issues as they arise.

Dynamic Task Performance, Cohesion, and Communications in Human Groups.

PubMed

Giraldo, Luis Felipe; Passino, Kevin M

2016-10-01

In the study of the behavior of human groups, it has been observed that there is a strong interaction between the cohesiveness of the group, its performance when the group has to solve a task, and the patterns of communication between the members of the group. Developing mathematical and computational tools for the analysis and design of task-solving groups that are not only cohesive but also perform well is of importance in social sciences, organizational management, and engineering. In this paper, we model a human group as a dynamical system whose behavior is driven by a task optimization process and the interaction between subsystems that represent the members of the group interconnected according to a given communication network. These interactions are described as attractions and repulsions among members. We show that the dynamics characterized by the proposed mathematical model are qualitatively consistent with those observed in real-human groups, where the key aspect is that the attraction patterns in the group and the commitment to solve the task are not static but change over time. Through a theoretical analysis of the system we provide conditions on the parameters that allow the group to have cohesive behaviors, and Monte Carlo simulations are used to study group dynamics for different sets of parameters, communication topologies, and tasks to solve.

Dynamic Modeling Strategy for Flow Regime Transition in Gas-Liquid Two-Phase Flows

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

Xia Wang; Xiaodong Sun; Benjamin Doup

In modeling gas-liquid two-phase flows, the concept of flow regimes has been widely used to characterize the global interfacial structure of the flows. Nearly all constitutive relations that provide closures to the interfacial transfers in two-phase flow models, such as the two-fluid model, are flow regime dependent. Current nuclear reactor safety analysis codes, such as RELAP5, classify flow regimes using flow regime maps or transition criteria that were developed for steady-state, fully-developed flows. As twophase flows are dynamic in nature, it is important to model the flow regime transitions dynamically to more accurately predict the two-phase flows. The present workmore » aims to develop a dynamic modeling strategy to determine flow regimes in gas-liquid two-phase flows through introduction of interfacial area transport equations (IATEs) within the framework of a two-fluid model. The IATE is a transport equation that models the interfacial area concentration by considering the creation of the interfacial area, fluid particle (bubble or liquid droplet) disintegration, boiling and evaporation, and the destruction of the interfacial area, fluid particle coalescence and condensation. For flow regimes beyond bubbly flows, a two-group IATE has been proposed, in which bubbles are divided into two groups based on their size and shapes, namely group-1 and group-2 bubbles. A preliminary approach to dynamically identify the flow regimes is discussed, in which discriminator s are based on the predicted information, such as the void fraction and interfacial area concentration. The flow regime predicted with this method shows good agreement with the experimental observations.« less

Developing Seventh Grade Students' Understanding of Complex Environmental Problems with Systems Tools and Representations: a Quasi-experimental Study

NASA Astrophysics Data System (ADS)

Doganca Kucuk, Zerrin; Saysel, Ali Kerem

2017-03-01

A systems-based classroom intervention on environmental education was designed for seventh grade students; the results were evaluated to see its impact on the development of systems thinking skills and standard science achievement and whether the systems approach is a more effective way to teach environmental issues that are dynamic and complex. A quasi-experimental methodology was used to compare performances of the participants in various dimensions, including systems thinking skills, competence in dynamic environmental problem solving and success in science achievement tests. The same pre-, post- and delayed tests were used with both the comparison and experimental groups in the same public middle school in Istanbul. Classroom activities designed for the comparison group (N = 20) followed the directives of the Science and Technology Curriculum, while the experimental group (N = 22) covered the same subject matter through activities benefiting from systems tools and representations such as behaviour over time graphs, causal loop diagrams, stock-flow structures and hands-on dynamic modelling. After a one-month systems-based instruction, the experimental group demonstrated significantly better systems thinking and dynamic environmental problem solving skills. Achievement in dynamic problem solving was found to be relatively stable over time. However, standard science achievement did not improve at all. This paper focuses on the quantitative analysis of the results, the weaknesses of the curriculum and educational implications.

Developing clinical leadership capability.

PubMed

Pintar, Kristi A; Capuano, Terry A; Rosser, Gwendolyn D

2007-01-01

Nursing facilities must be committed to ongoing leadership development and to developing and retaining their staff in the increasingly competitive healthcare market. In this article, the authors share the processes involved in creating a focused small group approach to developing clinical leaders. Programmatic approaches to development, clarity of needs of those targeted for development, individual development plans, external expertise partnerships, and small group session dynamics are discussed. Applications of the process and lessons learned from the program will benefit others in their efforts to enhance organization succession planning, leadership development, group learning, and program administration.

Psychotherapy with schizophrenics in team groups: a systems model.

PubMed

Beeber, A R

1991-01-01

This paper focuses on the treatment of patients with schizophrenic disorders employing the Team Group model. The advantages and disadvantages of the Team Group are presented. Systems theory and principles of group development are applied as a basis for understanding the dynamics of the group in the context at the acute psychiatric unit. Particular problems encountered in treating patients with schizophrenic disorders in this setting are presented. These include: (1) issues of therapist style and technique, (2) basic psychopathology of the schizophrenic disorders, and (3) phase-specific problems associated with the dynamics of the group. Recommendations for therapist interventions are made that may better integrate these patients into the Team Group.

Bridging the gap between interviewer and interviewee: developing an interview guide for individual interviews by means of a focus group.

PubMed

Pedersen, Birgith; Delmar, Charlotte; Falkmer, Ursula; Grønkjaer, Mette

2016-09-01

In developing an interview guide, pre-existing knowledge about the research topic is essential. In a recent study, we were interested in exploring the experiences of weight changes among women treated for breast cancer using individual interviews. However, to develop an interview guide for the individual interviews that covered relevant thematic and dynamic dimensions, we found existing literature insufficient. Thus, we turned our attention to the benefit of the focus group method. This study aims to discuss how a focus group prior to individual interviews may contribute in developing the thematic dimension and translating the dynamic dimension of an interview guide into everyday language. We conducted one focus group interview of five women treated for breast cancer with experiences in weight changes. Data were analysed using content and conversation analysis and discussed with relevant literature on interview guide development. The study is approved by the Danish Data Protection Agency (2008-58-0028) and follows the ethical guidelines for qualitative research. Data generation and analysis resulted in themes for the thematic dimension, as well as three dynamic areas to consider in the individual interviews to bridge the gap between the interviewer and the interviewee. The dynamic areas are as follows: The use of words, images and metaphors - a shield and self-protection, Multiple meanings to explore and Staying close to the everyday language. The analysis made us more familiar with the content and meaning of weight changes among breast cancer survivors. Furthermore, it provided images and metaphors, multiple meanings and a sense of the women's everyday language that calls for an open interview frame to be used in subsequent individual interviews. © 2015 Nordic College of Caring Science.

Dynamic Processes of Speech Development by Seven Adult Learners of Japanese in a Domestic Immersion Context

ERIC Educational Resources Information Center

Fukuda, Makiko

2014-01-01

The present study revealed the dynamic process of speech development in a domestic immersion program by seven adult beginning learners of Japanese. The speech data were analyzed with fluency, accuracy, and complexity measurements at group, interindividual, and intraindividual levels. The results revealed the complex nature of language development…

Impaired social brain network for processing dynamic facial expressions in autism spectrum disorders

PubMed Central

2012-01-01

Background Impairment of social interaction via facial expressions represents a core clinical feature of autism spectrum disorders (ASD). However, the neural correlates of this dysfunction remain unidentified. Because this dysfunction is manifested in real-life situations, we hypothesized that the observation of dynamic, compared with static, facial expressions would reveal abnormal brain functioning in individuals with ASD. We presented dynamic and static facial expressions of fear and happiness to individuals with high-functioning ASD and to age- and sex-matched typically developing controls and recorded their brain activities using functional magnetic resonance imaging (fMRI). Result Regional analysis revealed reduced activation of several brain regions in the ASD group compared with controls in response to dynamic versus static facial expressions, including the middle temporal gyrus (MTG), fusiform gyrus, amygdala, medial prefrontal cortex, and inferior frontal gyrus (IFG). Dynamic causal modeling analyses revealed that bi-directional effective connectivity involving the primary visual cortex–MTG–IFG circuit was enhanced in response to dynamic as compared with static facial expressions in the control group. Group comparisons revealed that all these modulatory effects were weaker in the ASD group than in the control group. Conclusions These results suggest that weak activity and connectivity of the social brain network underlie the impairment in social interaction involving dynamic facial expressions in individuals with ASD. PMID:22889284

Using Family Systems Theory in Career Counseling: A Group for Parents.

ERIC Educational Resources Information Center

Whiston, Susan C.

1989-01-01

Describes a counseling group for parents that focused on maximum parental involvement in their children's career development, blending traditional career exploration and family dynamics techniques. (TE)

Computer simulation of population dynamics inside the urban environment

NASA Astrophysics Data System (ADS)

Andreev, A. S.; Inovenkov, I. N.; Echkina, E. Yu.; Nefedov, V. V.; Ponomarenko, L. S.; Tikhomirov, V. V.

2017-12-01

In this paper using a mathematical model of the so-called “space-dynamic” approach we investigate the problem of development and temporal dynamics of different urban population groups. For simplicity we consider an interaction of only two population groups inside a single urban area with axial symmetry. This problem can be described qualitatively by a system of two non-stationary nonlinear differential equations of the diffusion type with boundary conditions of the third type. The results of numerical simulations show that with a suitable choice of the diffusion coefficients and interaction functions between different population groups we can receive different scenarios of population dynamics: from complete displacement of one population group by another (originally more “aggressive”) to the “peaceful” situation of co-existence of them together.

Group dynamics challenges: Insights from Biosphere 2 experiments

NASA Astrophysics Data System (ADS)

Nelson, Mark; Gray, Kathelin; Allen, John P.

2015-07-01

Successfully managing group dynamics of small, physically isolated groups is vital for long duration space exploration/habitation and for terrestrial CELSS (Controlled Environmental Life Support System) facilities with human participants. Biosphere 2 had important differences and shares some key commonalities with both Antarctic and space environments. There were a multitude of stress factors during the first two year closure experiment as well as mitigating factors. A helpful tool used at Biosphere 2 was the work of W.R. Bion who identified two competing modalities of behavior in small groups. Task-oriented groups are governed by conscious acceptance of goals, reality-thinking in relation to time and resources, and intelligent management of challenges. The opposing unconscious mode, the "basic-assumption" ("group animal") group, manifests through Dependency/Kill the Leader, Fight/Flight and Pairing. These unconscious dynamics undermine and can defeat the task group's goal. The biospherians experienced some dynamics seen in other isolated teams: factions developing reflecting personal chemistry and disagreements on overall mission procedures. These conflicts were exacerbated by external power struggles which enlisted support of those inside. Nevertheless, the crew evolved a coherent, creative life style to deal with some of the deprivations of isolation. The experience of the first two year closure of Biosphere 2 vividly illustrates both vicissitudes and management of group dynamics. The crew overrode inevitable frictions to creatively manage both operational and research demands and opportunities of the facility, thus staying 'on task' in Bion's group dynamics terminology. The understanding that Biosphere 2 was their life support system may also have helped the mission to succeed. Insights from the Biosphere 2 experience can help space and remote missions cope successfully with the inherent challenges of small, isolated crews.

Group dynamics challenges: Insights from Biosphere 2 experiments.

PubMed

Nelson, Mark; Gray, Kathelin; Allen, John P

2015-07-01

Successfully managing group dynamics of small, physically isolated groups is vital for long duration space exploration/habitation and for terrestrial CELSS (Controlled Environmental Life Support System) facilities with human participants. Biosphere 2 had important differences and shares some key commonalities with both Antarctic and space environments. There were a multitude of stress factors during the first two year closure experiment as well as mitigating factors. A helpful tool used at Biosphere 2 was the work of W.R. Bion who identified two competing modalities of behavior in small groups. Task-oriented groups are governed by conscious acceptance of goals, reality-thinking in relation to time and resources, and intelligent management of challenges. The opposing unconscious mode, the "basic-assumption" ("group animal") group, manifests through Dependency/Kill the Leader, Fight/Flight and Pairing. These unconscious dynamics undermine and can defeat the task group's goal. The biospherians experienced some dynamics seen in other isolated teams: factions developing reflecting personal chemistry and disagreements on overall mission procedures. These conflicts were exacerbated by external power struggles which enlisted support of those inside. Nevertheless, the crew evolved a coherent, creative life style to deal with some of the deprivations of isolation. The experience of the first two year closure of Biosphere 2 vividly illustrates both vicissitudes and management of group dynamics. The crew overrode inevitable frictions to creatively manage both operational and research demands and opportunities of the facility, thus staying 'on task' in Bion's group dynamics terminology. The understanding that Biosphere 2 was their life support system may also have helped the mission to succeed. Insights from the Biosphere 2 experience can help space and remote missions cope successfully with the inherent challenges of small, isolated crews. Copyright © 2015 The Committee on Space Research (COSPAR). Published by Elsevier Ltd. All rights reserved.

The influence of static magnetic field (50 mT) on development and motor behaviour of Tenebrio (Insecta, Coleoptera).

PubMed

Todorović, Dajana; Marković, Tamara; Prolić, Zlatko; Mihajlović, Spomenko; Rauš, Snežana; Nikolić, Ljiljana; Janać, Branka

2013-01-01

There is considerable concern about potential effects associated with exposure to magnetic fields on organisms. Therefore, duration of pupa-adult development and motor behaviour of adults were analyzed in Tenebrio obscursus and T. molitor after exposure to static magnetic field (50 mT). The experimental groups were: Control (kept 5 m from the magnets), groups which pupae and adults were placed closer to the North pole, or closer to the South pole of magnetic dipole. The pupae were exposed to the magnetic field until the moment of adult eclosion. The pupa-adult development dynamics were recorded daily. Subsequently, behaviour (distance travelled, average speed and immobility) of adults exposed to the magnetic field was monitored in a circular open field arena. Static magnetic field did not affect pupa-adult developmental dynamic of examined Tenebrio species. Exposure to magnetic field did not significantly change motor behaviour of T. obscurus adults. The changes in the motor behaviour of T. molitor induced by static magnetic field were opposite in two experimental groups developed closer to the North pole or closer to the South pole of magnetic dipole. Static magnetic field (50 mT) did not affect on pupa-adult development dynamic of two examined Tenebrio species, but modulated their motor behaviour.

Evolutionary dynamics of general group interactions in structured populations

NASA Astrophysics Data System (ADS)

Li, Aming; Broom, Mark; Du, Jinming; Wang, Long

2016-02-01

The evolution of populations is influenced by many factors, and the simple classical models have been developed in a number of important ways. Both population structure and multiplayer interactions have been shown to significantly affect the evolution of important properties, such as the level of cooperation or of aggressive behavior. Here we combine these two key factors and develop the evolutionary dynamics of general group interactions in structured populations represented by regular graphs. The traditional linear and threshold public goods games are adopted as models to address the dynamics. We show that for linear group interactions, population structure can favor the evolution of cooperation compared to the well-mixed case, and we see that the more neighbors there are, the harder it is for cooperators to persist in structured populations. We further show that threshold group interactions could lead to the emergence of cooperation even in well-mixed populations. Here population structure sometimes inhibits cooperation for the threshold public goods game, where depending on the benefit to cost ratio, the outcomes are bistability or a monomorphic population of defectors or cooperators. Our results suggest, counterintuitively, that structured populations are not always beneficial for the evolution of cooperation for nonlinear group interactions.

Exploring the Impact of Students' Learning Approach on Collaborative Group Modeling of Blood Circulation

ERIC Educational Resources Information Center

Lee, Shinyoung; Kang, Eunhee; Kim, Heui-Baik

2015-01-01

This study aimed to explore the effect on group dynamics of statements associated with deep learning approaches (DLA) and their contribution to cognitive collaboration and model development during group modeling of blood circulation. A group was selected for an in-depth analysis of collaborative group modeling. This group constructed a model in a…

The "Messy" Business of Academic Developers Leading Other Academic Developers: Critical Reflection on a Curriculum Realignment Exercise

ERIC Educational Resources Information Center

Thomas, Sharon; Cordiner, Moira

2014-01-01

Little has been written about academic developers (ADs) working in teams leading other ADs. This paper chronicles the experience of a group of ADs in one Australian university working on a curriculum realignment exercise. Unexpectedly the dominant theme in participants' reflections was group dynamics, not the process. We were confronted by…

Research activities of the Geodynamics Branch

NASA Technical Reports Server (NTRS)

Kahn, W. D. (Editor); Cohen, S. C. (Editor)

1984-01-01

A broad spectrum of geoscience disciplines including space geodesy, geopotential field modeling, tectonophysics, and dynamic oceanography are discussed. The NASA programs, include the Geodynamics and Ocean Programs, the Crustal Dynamics Project, the proposed Ocean Topography Experiment (TOPEX), and the Geopotential Research Mission (GRM). The papers are grouped into chapters on Crustal Movements, Global Earth Dynamics, Gravity Field Model Development, Sea Surface Topography, and Advanced Studies.

Convergent Adaptation in Small Groups: Understanding Professional Development Activities through a Complex Systems Lens

ERIC Educational Resources Information Center

Yoon, Susan; Liu, Lei; Goh, Sao-Ee

2010-01-01

Understanding the dynamics of individual or group adaptation can provide valuable information for constructing professional development strategies to increase chances of instructional success. This paper reports on an exploratory study that identifies indicators of convergent vs. non-convergent adaptation in two cases of teachers working together…

Professional Development Priorities Process (Needs Assessment). Leader's Handbook.

ERIC Educational Resources Information Center

Southeast Idaho Teacher Center Consortium, Twin Falls.

Step-by-step instructions are provided for implementing the Professional Development Priorities Process (PDPP), an educational needs assessment process, by a school faculty member with groups of eight peers or more. The essence of PDPP, which was designed at the Southeast Idaho Teacher Center Consortium, is a dynamic group process in which needs…

Ab Initio Potential Energy Surfaces and Quantum Dynamics for Polyatomic Bimolecular Reactions.

PubMed

Fu, Bina; Zhang, Dong H

2018-05-08

There has been great progress in the development of potential energy surfaces (PESs) and quantum dynamics calculations in the gas phase. The establishment of a fitting procedure for highly accurate PESs and new developments in quantum reactive scattering on reliable PESs allow accurate characterization of reaction dynamics beyond triatomic systems. This review will give the recent development in our group in constructing ab initio PESs based on neural networks and the time-dependent wave packet calculations for bimolecular reactions beyond three atoms. Bimolecular reactions of current interest to the community, namely, OH + H 2 , H + H 2 O, OH + CO, H + CH 4 , and Cl + CH 4 , are focused on. Quantum mechanical characterization of these reactions uncovers interesting dynamical phenomena with an unprecedented level of sophistication and has greatly advanced our understanding of polyatomic reaction dynamics.

Evolutionary game analysis and regulatory strategies for online group-buying based on system dynamics

NASA Astrophysics Data System (ADS)

Jiang, Zhong-Zhong; He, Na; Qin, Xuwei; Ip, W. H.; Wu, C. H.; Yung, K. L.

2018-07-01

The emergence of online group-buying provides a new consumption pattern for consumers in e-commerce era. However, many consumers realize that their own interests sometimes can't be guaranteed in the group-buying market due to the lack of being regulated. This paper aims to develop effective regulation strategies for online group-buying market. To the best of our knowledge, most existing studies assume that three parties in online group-buying market, i.e. the retailer, the group-buying platform and the consumer, are perfectly rational. To better understand the decision process, in this paper, we incorporate the concept of bounded rationality into consideration. Firstly, a three-parties evolutionary game model is established to study each player's game strategy based on bounded rationality. Secondly, the game model is simulated as a whole by adopting system dynamics to analyze its stability. Finally, theoretical analysis and extensive computational experiments are conducted to obtain the managerial insights and regulation strategies for online group-buying market. Our results clearly demonstrate that a suitable bonus-penalty measure can promote the healthy development of online group-buying market.

Structural Dynamics of Carbon Dots in Water and N, N-Dimethylformamide Probed by All-Atom Molecular Dynamics Simulations.

PubMed

Paloncýová, Markéta; Langer, Michal; Otyepka, Michal

2018-04-10

Carbon dots (CDs), one of the youngest members of the carbon nanostructure family, are now widely experimentally studied for their tunable fluorescence properties, bleaching resistance, and biocompatibility. Their interaction with biomolecular systems has also been explored experimentally. However, many atomistic details still remain unresolved. Molecular dynamics (MD) simulations enabling atomistic and femtosecond resolutions simultaneously are a well-established tool of computational chemistry which can provide useful insights into investigated systems. Here we present a full procedure for performing MD simulations of CDs. We developed a builder for generating CDs of a desired size and with various oxygen-containing surface functional groups. Further, we analyzed the behavior of various CDs differing in size, surface functional groups, and degrees of functionalization by MD simulations. These simulations showed that surface functionalized CDs are stable in a water environment through the formation of an extensive hydrogen bonding network. We also analyzed the internal dynamics of individual layers of CDs and evaluated the role of surface functional groups on CD stability. We observed that carboxyl groups interconnected the neighboring layers and decreased the rate of internal rotations. Further, we monitored changes in the CD shape caused by an excess of charged carboxyl groups or carbonyl groups. In addition to simulations in water, we analyzed the behavior of CDs in the organic solvent DMF, which decreased the stability of pure CDs but increased the level of interlayer hydrogen bonding. We believe that the developed protocol, builder, and parameters will facilitate future studies addressing various aspects of structural features of CDs and nanocomposites containing CDs.

In vivo dynamic compression has less detrimental effect than static compression on newly formed bone of a rat caudal vertebra

PubMed Central

Benoit, A.; Mustafy, T.; Londono, I.; Grimard, G.; Aubin, C-E.; Villemure, I.

2016-01-01

Fusionless devices are currently designed to treat spinal deformities such as scoliosis by the application of a controlled mechanical loading. Growth modulation by dynamic compression was shown to preserve soft tissues. The objective of this in vivo study was to characterize the effect of static vs. dynamic loading on the bone formed during growth modulation. Controlled compression was applied during 15 days on the 7th caudal vertebra (Cd7) of rats during growth spurt. The load was sustained in the “static” group and sinusoidally oscillating in the “dynamic” group. The effect of surgery and of the device was investigated using control and sham (operated on but no load applied) groups. A high resolution CT-scan of Cd7 was acquired at days 2, 8 and 15 of compression. Growth rates, histomorphometric parameters and mineral density of the newly formed bone were quantified and compared. Static and dynamic loadings significantly reduced the growth rate by 20% compared to the sham group. Dynamic loading preserved newly formed bone histomorphometry and mineral density whereas static loading induced thicker (+31%) and more mineralized (+12%) trabeculae. A significant sham effect was observed. Growth modulation by dynamic compression constitutes a promising way to develop new treatment for skeletal deformities. PMID:27609036

A role for low-order system dynamics models in urban health policy making.

PubMed

Newell, Barry; Siri, José

2016-10-01

Cities are complex adaptive systems whose responses to policy initiatives emerge from feedback interactions between their parts. Urban policy makers must routinely deal with both detail and dynamic complexity, coupled with high levels of diversity, uncertainty and contingency. In such circumstances, it is difficult to generate reliable predictions of health-policy outcomes. In this paper we explore the potential for low-order system dynamics (LOSD) models to make a contribution towards meeting this challenge. By definition, LOSD models have few state variables (≤5), illustrate the non-linear effects caused by feedback and accumulation, and focus on endogenous dynamics generated within well-defined boundaries. We suggest that experience with LOSD models can help practitioners to develop an understanding of basic principles of system dynamics, giving them the ability to 'see with new eyes'. Because efforts to build a set of LOSD models can help a transdisciplinary group to develop a shared, coherent view of the problems that they seek to tackle, such models can also become the foundations of 'powerful ideas'. Powerful ideas are conceptual metaphors that provide the members of a policy-making group with the a priori shared context required for effective communication, the co-production of knowledge, and the collaborative development of effective public health policies. Copyright © 2016 Elsevier Ltd. All rights reserved.

Interlimb symmetry of dynamic knee joint stiffness and co-contraction is maintained in early stage knee osteoarthritis.

PubMed

Collins, A T; Richardson, R T; Higginson, J S

2014-08-01

Individuals with knee OA often exhibit greater co-contraction of antagonistic muscle groups surrounding the affected joint which may lead to increases in dynamic joint stiffness. These detrimental changes in the symptomatic limb may also exist in the contralateral limb, thus contributing to its risk of developing knee osteoarthritis. The purpose of this study is to investigate the interlimb symmetry of dynamic knee joint stiffness and muscular co-contraction in knee osteoarthritis. Muscular co-contraction and dynamic knee joint stiffness were assessed in 17 subjects with mild to moderate unilateral medial compartment knee osteoarthritis and 17 healthy control subjects while walking at a controlled speed (1.0m/s). Paired and independent t-tests determined whether significant differences exist between groups (p<0.05). There were no significant differences in dynamic joint stiffness or co-contraction between the OA symptomatic and OA contralateral group (p=0.247, p=0.874, respectively) or between the OA contralateral and healthy group (p=0.635, p=0.078, respectively). There was no significant difference in stiffness between the OA symptomatic and healthy group (p=0.600); however, there was a slight trend toward enhanced co-contraction in the symptomatic knees compared to the healthy group (p=0.051). Subjects with mild to moderate knee osteoarthritis maintain symmetric control strategies during gait. Copyright © 2014 Elsevier Ltd. All rights reserved.

Interlimb symmetry of dynamic knee joint stiffness and co-contraction is maintained in early stage knee osteoarthritis

PubMed Central

Collins, A.T.; Richardson, R.T.; Higginson, J.S.

2014-01-01

Individuals with knee OA often exhibit greater co-contraction of antagonistic muscle groups surrounding the affected joint which may lead to increases in dynamic joint stiffness. These detrimental changes in the symptomatic limb may also exist in the contralateral limb, thus contributing to its risk of developing knee osteoarthritis. The purpose of this study is to investigate the interlimb symmetry of dynamic knee joint stiffness and muscular co-contraction in knee osteoarthritis. Muscular co-contraction and dynamic knee joint stiffness were assessed in 17 subjects with mild to moderate unilateral medial compartment knee osteoarthritis and 17 healthy control subjects while walking at a controlled speed (1.0 m/s). Paired and independent t-tests determined whether significant differences exist between groups (p < 0.05). There were no significant differences in dynamic joint stiffness or co-contraction between the OA symptomatic and OA contralateral group (p = 0.247, p = 0.874, respectively) or between the OA contralateral and healthy group (p = 0.635, p = 0.078, respectively). There was no significant difference in stiffness between the OA symptomatic and healthy group (p = 0.600); however, there was a slight trend toward enhanced co-contraction in the symptomatic knees compared to the healthy group (p = 0.051). Subjects with mild to moderate knee osteoarthritis maintain symmetric control strategies during gait. PMID:24768278

A longitudinal study of the sociosexual dynamics in a captive family group of wolves: the University of Connecticut wolf project.

PubMed

Jenks, Susan M

2011-11-01

An interest in the role of the social environment on the evolution of behavior led Professor Benson Ginsburg to studies of wolf social behavior. He initiated the University of Connecticut wolf project with a family group of wolves housed in a protected enclosure in an isolated area of campus. One aim of this project was to conduct a longitudinal study of a family group of wolves in order to understand the proximate behavioral mechanisms underlying mating dynamics with a degree of control and opportunistic observation that could not be achieved through field studies. The development of social relationships and the dynamics of mating were observed for 9 years. As in nature, agonistic relationships strongly influenced reproductive success, successful breeding was limited to a single pair each season, and the behavioral dynamics included status transitions with breeder rotations. Our work, when combined with the results of other captive wolf studies, has contributed valuable information to the general understanding of wolf social behavior, especially regarding the proximate behavior patterns underlying group social interactions and reproduction. This understanding has broadened perspectives on the dynamic interplay between social behavior and evolutionary processes.

The American Cowboy: Developing Small Group Social Studies Interaction Experiences in the Elementary Classroom.

ERIC Educational Resources Information Center

Holmes, Edward, Jr.

Appropriate for elementary school students, this resource unit on the American cowboy provides four activities for small group work. The unit also lists objectives and discusses the organization and dynamics of small groups. The general objective is for the student to learn how to work within groups and how to resolve group conflict. The…

[Mes differ by positioning: empirical testing of decentralized dynamics of the self].

PubMed

Mizokami, Shinichi

2013-10-01

The present study empirically tested the conceptualization of the decentralized dynamics of the self proposed by Hermans & Kempen (1993), which they developed theoretically and from clinical cases, not from large samples of empirical data. They posited that worldviews and images of the self could vary by positioning even in the same individual, and denied that the ego was an omniscient entity that knew and controlled all aspects of the self (centralized ego). Study 1 tested their conceptualization empirically with 47 university students in an experimental group and 17 as a control group. The results showed that the scores on the Rosenberg's self-esteem scale and images of the Mes in the experimental group significantly varied by positioning, but those in the control group did not. Similar results were found in Study 2 with a sample of 120 university students. These results empirically supported the conceptualization of the decentralized dynamics of the self.

Emergence of grouping in multi-resource minority game dynamics

NASA Astrophysics Data System (ADS)

Huang, Zi-Gang; Zhang, Ji-Qiang; Dong, Jia-Qi; Huang, Liang; Lai, Ying-Cheng

2012-10-01

Complex systems arising in a modern society typically have many resources and strategies available for their dynamical evolutions. To explore quantitatively the behaviors of such systems, we propose a class of models to investigate Minority Game (MG) dynamics with multiple strategies. In particular, agents tend to choose the least used strategies based on available local information. A striking finding is the emergence of grouping states defined in terms of distinct strategies. We develop an analytic theory based on the mean-field framework to understand the ``bifurcations'' of the grouping states. The grouping phenomenon has also been identified in the Shanghai Stock-Market system, and we discuss its prevalence in other real-world systems. Our work demonstrates that complex systems obeying the MG rules can spontaneously self-organize themselves into certain divided states, and our model represents a basic and general mathematical framework to address this kind of phenomena in social, economical and political systems.

Feminist Research Methodology Groups: Origins, Forms, Functions.

ERIC Educational Resources Information Center

Reinharz, Shulamit

Feminist Research Methodology Groups (FRMGs) have developed as a specific type of women's group in which feminist academics can find supportive audiences for their work while contributing to a feminist redefinition of research methods. An analysis of two FRMGs reveals common characteristics, dynamics, and outcomes. Both were limited to small…

Working with Difference in Online Collaborative Groups

ERIC Educational Resources Information Center

Smith, Regina O.

2005-01-01

This qualitative cross-case study explored the experiences that learners describe within online collaborative groups. The study context was a fully online graduate course on adult learning. The findings suggest that the small online groups demonstrated dynamics and process that are characteristic of individual growth and development and group…

Dynamics in the Decompositions Approach to Quantum Mechanics

NASA Astrophysics Data System (ADS)

Harding, John

2017-12-01

In Harding (Trans. Amer. Math. Soc. 348(5), 1839-1862 1996) it was shown that the direct product decompositions of any non-empty set, group, vector space, and topological space X form an orthomodular poset Fact X. This is the basis for a line of study in foundational quantum mechanics replacing Hilbert spaces with other types of structures. Here we develop dynamics and an abstract version of a time independent Schrödinger's equation in the setting of decompositions by considering representations of the group of real numbers in the automorphism group of the orthomodular poset Fact X of decompositions.

Evaluations of and Reasoning about Normative and Deviant Ingroup and Outgroup Members: Development of the Black Sheep Effect

ERIC Educational Resources Information Center

Abrams, Dominic; Palmer, Sally B.; Rutland, Adam; Cameron, Lindsey; Van de Vyver, Julie

2014-01-01

Research with adults has demonstrated a "black sheep effect" (BSE) whereby, relative to evaluations of normative group members, ingroup deviants are derogated more than outgroup deviants. The developmental subjective group dynamics (DSGD) model holds that the BSE should develop during middle childhood when children apply wider social…

Revitalizing Young Adults through Leadership Training at Victory Presbyterian Church, Ilsan, Korea

ERIC Educational Resources Information Center

Noh, Kyeong Cheon

2009-01-01

This study has the aim of examining the effects obtained mainly through the leadership development process through small group dynamics for the purpose of making the youth group church, vitalized. The church reached the conclusion that the important problem for continuous church development was how to find a trained leader and to help the…

The Administrative Team: Dynamism vs. Dysfunction

ERIC Educational Resources Information Center

Tyson, Nathan

2008-01-01

Before real success can come to any school, the administrative team must become a dynamic entity. The team and its ability to work within the school setting are fundamental to improving instruction and increasing student achievement. The team spirit that this group develops has ramifications on school climate that directly affect teachers,…

A Lie-Theoretic Perspective on O(n) Mass Matrix Inversion for Serial Manipulators and Polypeptide Chains.

PubMed

Lee, Kiju; Wang, Yunfeng; Chirikjian, Gregory S

2007-11-01

Over the past several decades a number of O(n) methods for forward and inverse dynamics computations have been developed in the multi-body dynamics and robotics literature. A method was developed in 1974 by Fixman for O(n) computation of the mass-matrix determinant for a serial polymer chain consisting of point masses. In other recent papers, we extended this method in order to compute the inverse of the mass matrix for serial chains consisting of point masses. In the present paper, we extend these ideas further and address the case of serial chains composed of rigid-bodies. This requires the use of relatively deep mathematics associated with the rotation group, SO(3), and the special Euclidean group, SE(3), and specifically, it requires that one differentiates functions of Lie-group-valued argument.

Group Collaboration in Organizations: Architectures, Methodologies and Tools

DTIC Science & Technology

2002-03-01

collaboration , its definition and characteristics was completed. Next, existing technologies and standards were studied as well as the ...2000). 22 For effective collaboration , the technology must support the dynamic world of work be it individual, group and/or teamwork, as well as... develop it or simply use it as the basis of discussion. If collaborators are all contributing to the development of a

The space shuttle payload planning working groups. Volume 8: Earth and ocean physics

NASA Technical Reports Server (NTRS)

1973-01-01

The findings and recommendations of the Earth and Ocean Physics working group of the space shuttle payload planning activity are presented. The requirements for the space shuttle mission are defined as: (1) precision measurement for earth and ocean physics experiments, (2) development and demonstration of new and improved sensors and analytical techniques, (3) acquisition of surface truth data for evaluation of new measurement techniques, (4) conduct of critical experiments to validate geophysical phenomena and instrumental results, and (5) development and validation of analytical/experimental models for global ocean dynamics and solid earth dynamics/earthquake prediction. Tables of data are presented to show the flight schedule estimated costs, and the mission model.

Hybrid Instrumentation in Lumbar Spinal Fusion: A Biomechanical Evaluation of Three Different Instrumentation Techniques.

PubMed

Obid, Peter; Danyali, Reza; Kueny, Rebecca; Huber, Gerd; Reichl, Michael; Richter, Alexander; Niemeyer, Thomas; Morlock, Michael; Püschel, Klaus; Übeyli, Hüseyin

2017-02-01

Ex vivo human cadaveric study. The development or progression of adjacent segment disease (ASD) after spine stabilization and fusion is a major problem in spine surgery. Apart from optimal balancing of the sagittal profile, dynamic instrumentation is often suggested to prevent or impede ASD. Hybrid instrumentation is used to gain stabilization while allowing motion to avoid hypermobility in the adjacent segment. In this biomechanical study, the effects of two different hybrid instrumentations on human cadaver spines were evaluated and compared with a rigid instrumentation. Eighteen human cadaver spines (T11-L5) were subdivided into three groups: rigid, dynamic, and hook comprising six spines each. Clinical parameters and initial mechanical characteristics were consistent among groups. All specimens received rigid fixation from L3-L5 followed by application of a free bending load of extension and flexion. The range of motion (ROM) for every segment was evaluated. For the rigid group, further rigid fixation from L1-L5 was applied. A dynamic Elaspine system (Spinelab AG, Winterthur, Switzerland) was applied from L1 to L3 for the dynamic group, and the hook group was instrumented with additional laminar hooks at L1-L3. ROM was then evaluated again. There was no significant difference in ROM among the three instrumentation techniques. Based on this data, the intended advantage of a hybrid or dynamic instrumentation might not be achieved.

Capturing dynamic processes of change in GROW mutual help groups for mental health.

PubMed

Finn, Lizzie D; Bishop, Brian J; Sparrow, Neville

2009-12-01

The need for a model that can portray dynamic processes of change in mutual help groups for mental health (MHGMHs) is emphasized. A dynamic process model has the potential to capture a more comprehensive understanding of how MHGMHs may assist their members. An investigation into GROW, a mutual help organization for mental health, employed ethnographic, phenomenological and collaborative research methods. The study examined how GROW impacts on psychological well being. Study outcomes aligned with the social ecological paradigm (Maton in Understanding the self-help organization: frameworks and findings. Sage, Thousand Oaks 1994) indicating multifactorial processes of change at and across three levels of analysis: group level, GROW program/community level and individual level. Outcome themes related to life skills acquisition and a change in self-perception in terms of belonging within community and an increased sense of personal value. The GROW findings are used to assist development of a dynamic multi-dimensional process model to explain how MHGMHs may promote positive change.

H-division quarterly report, October--December 1977. [Lawrence Livermore Laboratory

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

Not Available

1978-02-10

The Theoretical EOS Group develops theoretical techniques for describing material properties under extreme conditions and constructs equation-of-state (EOS) tables for specific applications. Work this quarter concentrated on a Li equation of state, equation of state for equilibrium plasma, improved ion corrections to the Thomas--Fermi--Kirzhnitz theory, and theoretical estimates of high-pressure melting in metals. The Experimental Physics Group investigates properties of materials at extreme conditions of pressure and temperature, and develops new experimental techniques. Effort this quarter concerned the following: parabolic projectile distortion in the two-state light-gas gun, construction of a ballistic range for long-rod penetrators, thermodynamics and sound velocities inmore » liquid metals, isobaric expansion measurements in Pt, and calculation of the velocity--mass profile of a jet produced by a shaped charge. Code development was concentrated on the PELE code, a multimaterial, multiphase, explicit finite-difference Eulerian code for pool suppression dynamics of a hypothetical loss-of-coolant accident in a nuclear reactor. Activities of the Fluid Dynamics Group were directed toward development of a code to compute the equations of state and transport properties of liquid metals (e.g. Li) and partially ionized dense plasmas, jet stability in the Li reactor system, and the study and problem application of fluid dynamic turbulence theory. 19 figures, 5 tables. (RWR)« less

Emotional influence in groups: the dynamic nexus of affect, cognition, and behavior.

PubMed

van Kleef, Gerben A; Heerdink, Marc W; Homan, Astrid C

2017-10-01

Groups are a natural breeding ground for emotions. Group life affords unique opportunities but also poses critical challenges that may arouse emotional reactions in group members. Social-functional approaches hold that these emotions in turn contribute to group functioning by prompting group members to address concerns that are relevant to the group's success. Guided by Emotions as Social Information (EASI) theory, this paper reviews research on the affective, cognitive, and behavioral consequences of emotional expressions in groups. Affective processes include emotional contagion and affective convergence, and resulting states such as group affective tone and affective diversity. Cognitive processes include inferences group members draw from each other's emotional expressions. We discuss how these affective and cognitive processes shape behavior and group functioning. We conclude that the traditional (over)emphasis on affective processes must be complemented with a focus on cognitive processes to develop a more complete understanding of the social dynamics of emotions in groups. Copyright © 2017 Elsevier Ltd. All rights reserved.

Technology Transfer: A Contact Sport

NASA Technical Reports Server (NTRS)

Paynter, Nina P.

1995-01-01

Technology transfer is a dynamic process, involving dynamic people as the bridge between NASA Langley Research Center and the outside world. This bridge, for nonaerospace applications, is known as the Technology Applications Group. The introduction of new innovations and expertise where they are needed occurs through a 'push' and 'pull' process. A 'push' occurs when a new technology is first developed with high commercial potential and then a company is found to licence or further develop the technology. The 'pull' process occurs through problem statements. A company or group will submit a written statement of what they need and the shortcomings of commercially available technology. The Technology Transfer Team (T3) reviews these problem statements and decides where NASA LaRC can offer assistance. A researcher or group of researchers are then identified who can help solve the problem and they are put in contact with the company. Depending upon the situation in either method, a Space Act Agreement (SAA), or outline of the responsibilities for each party, is developed.

Toward Affective Development: A Program to Stimulate Psychological and Affective Development.

ERIC Educational Resources Information Center

Pearl, Linda F.

1987-01-01

Toward Affective Development (TAD), a 191-lesson program designed to stimulate psychological and affective development for third- through sixth-graders, can be used in special education, resource rooms, and remedial settings. TAD's five sections encompass: openness to experience, effects of emotions, group dynamics, individuality, and conflict…

Dynamic assessment of school-age children's narrative ability: an experimental investigation of classification accuracy.

PubMed

Peña, Elizabeth D; Gillam, Ronald B; Malek, Melynn; Ruiz-Felter, Roxanna; Resendiz, Maria; Fiestas, Christine; Sabel, Tracy

2006-10-01

Two experiments examined reliability and classification accuracy of a narration-based dynamic assessment task. The first experiment evaluated whether parallel results were obtained from stories created in response to 2 different wordless picture books. If so, the tasks and measures would be appropriate for assessing pretest and posttest change within a dynamic assessment format. The second experiment evaluated the extent to which children with language impairments performed differently than typically developing controls on dynamic assessment of narrative language. In the first experiment, 58 1st- and 2nd-grade children told 2 stories about wordless picture books. Stories were rated on macrostructural and microstructural aspects of language form and content, and the ratings were subjected to reliability analyses. In the second experiment, 71 children participated in dynamic assessment. There were 3 phases: a pretest phase, in which children created a story that corresponded to 1 of the wordless picture books from Experiment 1; a teaching phase, in which children attended 2 short mediation sessions that focused on storytelling ability; and a posttest phase, in which children created a story that corresponded to a second wordless picture book from Experiment 1. Analyses compared the pretest and posttest stories that were told by 2 groups of children who received mediated learning (typical and language impaired groups) and a no-treatment control group of typically developing children from Experiment 1. The results of the first experiment indicated that the narrative measures applied to stories about 2 different wordless picture books had good internal consistency. In Experiment 2, typically developing children who received mediated learning demonstrated a greater amount of pretest to posttest change than children in the language impaired and control groups. Classification analysis indicated better specificity and sensitivity values for measures of response to intervention (modifiability) and posttest storytelling than for measures of pretest storytelling. Observation of modifiability was the single best indicator of language impairment. Posttest measures and modifiability together yielded no misclassifications. The first experiment supported the use of 2 wordless picture books as stimulus materials for collecting narratives before and after mediation within a dynamic assessment paradigm. The second experiment supported the use of dynamic assessment for accurately identifying language impairments in school-age children.

Dynamic Assessment of School-Age Children’s Narrative Ability

PubMed Central

Peña, Elizabeth D.; Gillam, Ronald B.; Malek, Melynn; Ruiz-Felter, Roxanna; Resendiz, Maria; Fiestas, Christine; Sabel, Tracy

2008-01-01

Two experiments examined reliability and classification accuracy of a narration-based dynamic assessment task. Purpose The first experiment evaluated whether parallel results were obtained from stories created in response to 2 different wordless picture books. If so, the tasks and measures would be appropriate for assessing pretest and posttest change within a dynamic assessment format. The second experiment evaluated the extent to which children with language impairments performed differently than typically developing controls on dynamic assessment of narrative language. Method In the first experiment, 58 1st- and 2nd-grade children told 2 stories about wordless picture books. Stories were rated on macrostructural and microstructural aspects of language form and content, and the ratings were subjected to reliability analyses. In the second experiment, 71 children participated in dynamic assessment. There were 3 phases: a pretest phase, in which children created a story that corresponded to 1 of the wordless picture books from Experiment 1; a teaching phase, in which children attended 2 short mediation sessions that focused on storytelling ability; and a posttest phase, in which children created a story that corresponded to a second wordless picture book from Experiment 1. Analyses compared the pretest and posttest stories that were told by 2 groups of children who received mediated learning (typical and language impaired groups) and a no-treatment control group of typically developing children from Experiment 1. Results The results of the first experiment indicated that the narrative measures applied to stories about 2 different wordless picture books had good internal consistency. In Experiment 2, typically developing children who received mediated learning demonstrated a greater amount of pretest to posttest change than children in the language impaired and control groups. Classification analysis indicated better specificity and sensitivity values for measures of response to intervention (modifiability) and posttest storytelling than for measures of pretest storytelling. Observation of modifiability was the single best indicator of language impairment. Posttest measures and modifiability together yielded no misclassifications. Conclusion The first experiment supported the use of 2 wordless picture books as stimulus materials for collecting narratives before and after mediation within a dynamic assessment paradigm. The second experiment supported the use of dynamic assessment for accurately identifying language impairments in school-age children. PMID:17077213

Hybrid Surgery Combined with Dynamic Stabilization System and Fusion for the Multilevel Degenerative Disease of the Lumbosacral Spine.

PubMed

Lee, Soo Eon; Jahng, Tae-Ahn; Kim, Hyun Jib

2015-01-01

As motion-preserving technique has been developed, the concept of hybrid surgery involves simultaneous application of two different kinds of devices, dynamic stabilization system and fusion technique. In the present study, the application of hybrid surgery for lumbosacral degenerative disease involving two-segments and its long-term outcome were investigated. Fifteen patients with hybrid surgery (Hybrid group) and 10 patients with two-segment fusion (Fusion group) were retrospectively compared. Preoperative grade for disc degeneration was not different between the two groups, and the most common operated segment had the most degenerated disc grade in both groups; L4-5 and L5-S1 in the Hybrid group, and L3-4 and L4-5 in Fusion group. Over 48 months of follow-up, lumbar lordosis and range of motion (ROM) at the T12-S1 global segment were preserved in the Hybrid group, and the segmental ROM at the dynamic stabilized segment maintained at final follow-up. The Fusion group had a significantly decreased global ROM and a decreased segmental ROM with larger angles compared to the Hybrid group. Defining a 2-mm decrease in posterior disc height (PDH) as radiologic adjacent segment pathology (ASP), these changes were observed in 6 and 7 patients in the Hybrid and Fusion group, respectively. However, the last PDH at the above adjacent segment had statistically higher value in Hybrid group. Pain score for back and legs was much reduced in both groups. Functional outcome measured by Oswestry disability index (ODI), however, had better improvement in Hybrid group. Hybrid surgery, combined dynamic stabilization system and fusion, can be effective surgical treatment for multilevel degenerative lumbosacral spinal disease, maintaining lumbar motion and delaying disc degeneration.

Hybrid Surgery Combined with Dynamic Stabilization System and Fusion for the Multilevel Degenerative Disease of the Lumbosacral Spine

PubMed Central

Lee, Soo Eon; Kim, Hyun Jib

2015-01-01

Background As motion-preserving technique has been developed, the concept of hybrid surgery involves simultaneous application of two different kinds of devices, dynamic stabilization system and fusion technique. In the present study, the application of hybrid surgery for lumbosacral degenerative disease involving two-segments and its long-term outcome were investigated. Methods Fifteen patients with hybrid surgery (Hybrid group) and 10 patients with two-segment fusion (Fusion group) were retrospectively compared. Results Preoperative grade for disc degeneration was not different between the two groups, and the most common operated segment had the most degenerated disc grade in both groups; L4-5 and L5-S1 in the Hybrid group, and L3-4 and L4-5 in Fusion group. Over 48 months of follow-up, lumbar lordosis and range of motion (ROM) at the T12-S1 global segment were preserved in the Hybrid group, and the segmental ROM at the dynamic stabilized segment maintained at final follow-up. The Fusion group had a significantly decreased global ROM and a decreased segmental ROM with larger angles compared to the Hybrid group. Defining a 2-mm decrease in posterior disc height (PDH) as radiologic adjacent segment pathology (ASP), these changes were observed in 6 and 7 patients in the Hybrid and Fusion group, respectively. However, the last PDH at the above adjacent segment had statistically higher value in Hybrid group. Pain score for back and legs was much reduced in both groups. Functional outcome measured by Oswestry disability index (ODI), however, had better improvement in Hybrid group. Conclusion Hybrid surgery, combined dynamic stabilization system and fusion, can be effective surgical treatment for multilevel degenerative lumbosacral spinal disease, maintaining lumbar motion and delaying disc degeneration. PMID:26484008

DYNAMIC MODELING STRATEGY FOR FLOW REGIME TRANSITION IN GAS-LIQUID TWO-PHASE FLOWS

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

X. Wang; X. Sun; H. Zhao

In modeling gas-liquid two-phase flows, the concept of flow regime has been used to characterize the global interfacial structure of the flows. Nearly all constitutive relations that provide closures to the interfacial transfers in two-phase flow models, such as the two-fluid model, are often flow regime dependent. Currently, the determination of the flow regimes is primarily based on flow regime maps or transition criteria, which are developed for steady-state, fully-developed flows and widely applied in nuclear reactor system safety analysis codes, such as RELAP5. As two-phase flows are observed to be dynamic in nature (fully-developed two-phase flows generally do notmore » exist in real applications), it is of importance to model the flow regime transition dynamically for more accurate predictions of two-phase flows. The present work aims to develop a dynamic modeling strategy for determining flow regimes in gas-liquid two-phase flows through the introduction of interfacial area transport equations (IATEs) within the framework of a two-fluid model. The IATE is a transport equation that models the interfacial area concentration by considering the creation and destruction of the interfacial area, such as the fluid particle (bubble or liquid droplet) disintegration, boiling and evaporation; and fluid particle coalescence and condensation, respectively. For the flow regimes beyond bubbly flows, a two-group IATE has been proposed, in which bubbles are divided into two groups based on their size and shape (which are correlated), namely small bubbles and large bubbles. A preliminary approach to dynamically identifying the flow regimes is provided, in which discriminators are based on the predicted information, such as the void fraction and interfacial area concentration of small bubble and large bubble groups. This method is expected to be applied to computer codes to improve their predictive capabilities of gas-liquid two-phase flows, in particular for the applications in which flow regime transition occurs.« less

Trophic groups and modules: two levels of group detection in food webs

PubMed Central

Gauzens, Benoit; Thébault, Elisa; Lacroix, Gérard; Legendre, Stéphane

2015-01-01

Within food webs, species can be partitioned into groups according to various criteria. Two notions have received particular attention: trophic groups (TGs), which have been used for decades in the ecological literature, and more recently, modules. The relationship between these two group concepts remains unknown in empirical food webs. While recent developments in network theory have led to efficient methods for detecting modules in food webs, the determination of TGs (groups of species that are functionally similar) is largely based on subjective expert knowledge. We develop a novel algorithm for TG detection. We apply this method to empirical food webs and show that aggregation into TGs allows for the simplification of food webs while preserving their information content. Furthermore, we reveal a two-level hierarchical structure where modules partition food webs into large bottom–top trophic pathways, whereas TGs further partition these pathways into groups of species with similar trophic connections. This provides new perspectives for the study of dynamical and functional consequences of food-web structure, bridging topological and dynamical analysis. TGs have a clear ecological meaning and are found to provide a trade-off between network complexity and information loss. PMID:25878127

Digital Citizenship within Global Contexts

ERIC Educational Resources Information Center

Searson, Michael; Hancock, Marsali; Soheil, Nusrat; Shepherd, Gregory

2015-01-01

EduSummIT 2013 featured a working group that examined digital citizenship within a global context. Group members recognized that, given today's international, regional, political, and social dynamics, the notion of "global" might be more aspirational than practical. The development of informed policies and practices serving and involving…

Assessing social engagement in heterogeneous groups of zebrafish: a new paradigm for autism-like behavioral responses.

PubMed

Maaswinkel, Hans; Zhu, Liqun; Weng, Wei

2013-01-01

Because of its highly developed social character, zebrafish is a promising model system for the study of the genetic and neurochemical basis of altered social engagement such as is common in autism and schizophrenia. The traditional shoaling paradigm investigates social cohesion in homogeneous groups of zebrafish. However, the social dynamics of mixed groups is gaining interest from a therapeutic point of view and thus warrants animal modeling. Furthermore, mutant zebrafish are not always available in large numbers. Therefore, we developed a new paradigm that allows exploring shoaling in heterogeneous groups. The effects of MK-801, a non-competitive antagonist of the glutamate N-methyl-D-aspartate (NMDA) receptor, on social cohesion were studied to evaluate the paradigm. The drug has previously been shown to mimic aspects of autism and schizophrenia. Our results show that a single MK-801-treated zebrafish reduced social cohesion of the entire shoal drastically. Preliminary observations suggest that the social dynamics of the shoal as a whole was altered.

Assessing Social Engagement in Heterogeneous Groups of Zebrafish: A New Paradigm for Autism-Like Behavioral Responses

PubMed Central

Maaswinkel, Hans; Zhu, Liqun; Weng, Wei

2013-01-01

Because of its highly developed social character, zebrafish is a promising model system for the study of the genetic and neurochemical basis of altered social engagement such as is common in autism and schizophrenia. The traditional shoaling paradigm investigates social cohesion in homogeneous groups of zebrafish. However, the social dynamics of mixed groups is gaining interest from a therapeutic point of view and thus warrants animal modeling. Furthermore, mutant zebrafish are not always available in large numbers. Therefore, we developed a new paradigm that allows exploring shoaling in heterogeneous groups. The effects of MK-801, a non-competitive antagonist of the glutamate N-methyl-D-aspartate (NMDA) receptor, on social cohesion were studied to evaluate the paradigm. The drug has previously been shown to mimic aspects of autism and schizophrenia. Our results show that a single MK-801-treated zebrafish reduced social cohesion of the entire shoal drastically. Preliminary observations suggest that the social dynamics of the shoal as a whole was altered. PMID:24116082

Assessing the Internal Dynamics of Mathematical Problem Solving in Small Groups.

ERIC Educational Resources Information Center

Artzt, Alice F.; Armour-Thomas, Eleanor

The purpose of this exploratory study was to examine the problem-solving behaviors and perceptions of (n=27) seventh-grade students as they worked on solving a mathematical problem within a small-group setting. An assessment system was developed that allowed for this analysis. To assess problem-solving behaviors within a small group a Group…

Group Dynamics in the Language Classroom: Embodied Participation as Active Reception in the Collective Zone of Proximal Development

ERIC Educational Resources Information Center

van Compernolle, Rémi A.; Williams, Lawrence

2013-01-01

This article explores the notion of "active reception" during small-group collaborative interaction in the foreign language classroom, focusing on the embodied participation of a secondary (nonspeaking) interactant, Diane. Drawing on Vygotskian sociocultural theory, we argue that within small-group work, a Zone of Proximal Development…

Group Communication through Computers. Volume 1: Design and Use of the FORUM System. IFF Report R-32.

ERIC Educational Resources Information Center

Vallee, Jacques; And Others

To explore the feasibility and usefulness of group communication via computer, a system called FORUM was constructed and used in research and management tasks using ARPANET, an international computer network. Working softward and data regarding the dynamics of groups using network communication were developed, and a prototype hardware system for…

Group typicality, group loyalty and cognitive development.

PubMed

Patterson, Meagan M

2014-09-01

Over the course of childhood, children's thinking about social groups changes in a variety of ways. Developmental Subjective Group Dynamics (DSGD) theory emphasizes children's understanding of the importance of conforming to group norms. Abrams et al.'s study, which uses DSGD theory as a framework, demonstrates the social cognitive skills underlying young elementary school children's thinking about group norms. Future research on children's thinking about groups and group norms should explore additional elements of this topic, including aspects of typicality beyond loyalty. © 2014 The British Psychological Society.

Application of system dynamics and participatory spatial group model building in animal health: A case study of East Coast Fever interventions in Lundazi and Monze districts of Zambia

PubMed Central

Skjerve, Eystein; Rich, Magda; Rich, Karl M.

2017-01-01

East Coast Fever (ECF) is the most economically important production disease among traditional beef cattle farmers in Zambia. Despite the disease control efforts by the government, donors, and farmers, ECF cases are increasing. Why does ECF oscillate over time? Can alternative approaches such as systems thinking contribute solutions to the complex ECF problem, avoid unintended consequences, and achieve sustainable results? To answer these research questions and inform the design and implementation of ECF interventions, we qualitatively investigated the influence of dynamic socio-economic, cultural, and ecological factors. We used system dynamics modelling to specify these dynamics qualitatively, and an innovative participatory framework called spatial group model building (SGMB). SGMB uses participatory geographical information system (GIS) concepts and techniques to capture the role of spatial phenomenon in the context of complex systems, allowing stakeholders to identify spatial phenomenon directly on physical maps and integrate such information in model development. Our SGMB process convened focus groups of beef value chain stakeholders in two distinct production systems. The focus groups helped to jointly construct a series of interrelated system dynamics models that described ECF in a broader systems context. Thus, a complementary objective of this study was to demonstrate the applicability of system dynamics modelling and SGMB in animal health. The SGMB process revealed policy leverage points in the beef cattle value chain that could be targeted to improve ECF control. For example, policies that develop sustainable and stable cattle markets and improve household income availability may have positive feedback effects on investment in animal health. The results obtained from a SGMB process also demonstrated that a “one-size-fits-all” approach may not be equally effective in policing ECF in different agro-ecological zones due to the complex interactions of socio-ecological context with important, and often ignored, spatial patterns. PMID:29244862

Application of system dynamics and participatory spatial group model building in animal health: A case study of East Coast Fever interventions in Lundazi and Monze districts of Zambia.

PubMed

Mumba, Chisoni; Skjerve, Eystein; Rich, Magda; Rich, Karl M

2017-01-01

East Coast Fever (ECF) is the most economically important production disease among traditional beef cattle farmers in Zambia. Despite the disease control efforts by the government, donors, and farmers, ECF cases are increasing. Why does ECF oscillate over time? Can alternative approaches such as systems thinking contribute solutions to the complex ECF problem, avoid unintended consequences, and achieve sustainable results? To answer these research questions and inform the design and implementation of ECF interventions, we qualitatively investigated the influence of dynamic socio-economic, cultural, and ecological factors. We used system dynamics modelling to specify these dynamics qualitatively, and an innovative participatory framework called spatial group model building (SGMB). SGMB uses participatory geographical information system (GIS) concepts and techniques to capture the role of spatial phenomenon in the context of complex systems, allowing stakeholders to identify spatial phenomenon directly on physical maps and integrate such information in model development. Our SGMB process convened focus groups of beef value chain stakeholders in two distinct production systems. The focus groups helped to jointly construct a series of interrelated system dynamics models that described ECF in a broader systems context. Thus, a complementary objective of this study was to demonstrate the applicability of system dynamics modelling and SGMB in animal health. The SGMB process revealed policy leverage points in the beef cattle value chain that could be targeted to improve ECF control. For example, policies that develop sustainable and stable cattle markets and improve household income availability may have positive feedback effects on investment in animal health. The results obtained from a SGMB process also demonstrated that a "one-size-fits-all" approach may not be equally effective in policing ECF in different agro-ecological zones due to the complex interactions of socio-ecological context with important, and often ignored, spatial patterns.

Storyline Visualizations of Eye Tracking of Movie Viewing

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

Balint, John T.; Arendt, Dustin L.; Blaha, Leslie M.

Storyline visualizations offer an approach that promises to capture the spatio-temporal characteristics of individual observers and simultaneously illustrate emerging group behaviors. We develop a visual analytics approach to parsing, aligning, and clustering fixation sequences from eye tracking data. Visualization of the results captures the similarities and differences across a group of observers performing a common task. We apply our storyline approach to visualize gaze patterns of people watching dynamic movie clips. Storylines mitigate some of the shortcomings of existent spatio-temporal visualization techniques and, importantly, continue to highlight individual observer behavioral dynamics.

A Lie-Theoretic Perspective on O(n) Mass Matrix Inversion for Serial Manipulators and Polypeptide Chains

PubMed Central

Lee, Kiju; Wang, Yunfeng; Chirikjian, Gregory S.

2010-01-01

Over the past several decades a number of O(n) methods for forward and inverse dynamics computations have been developed in the multi-body dynamics and robotics literature. A method was developed in 1974 by Fixman for O(n) computation of the mass-matrix determinant for a serial polymer chain consisting of point masses. In other recent papers, we extended this method in order to compute the inverse of the mass matrix for serial chains consisting of point masses. In the present paper, we extend these ideas further and address the case of serial chains composed of rigid-bodies. This requires the use of relatively deep mathematics associated with the rotation group, SO(3), and the special Euclidean group, SE(3), and specifically, it requires that one differentiates functions of Lie-group-valued argument. PMID:20165563

Personal Identification by Keystroke Dynamics in Japanese Free Text Typing

NASA Astrophysics Data System (ADS)

Samura, Toshiharu; Nishimura, Haruhiko

Biometrics is classified into verification and identification. Many researchers on the keystroke dynamics have treated the verification of a fixed short password which is used for the user login. In this research, we pay attention to the identification and investigate several characteristics of the keystroke dynamics in Japanese free text typing. We developed Web-based typing software in order to collect the keystroke data on the Local Area Network and performed experiments on a total of 112 subjects, from which three groups of typing level, the beginner's level and above, the normal level and above and the middle level and above were constructed. Based on the identification methods by the weighted Euclid distance and the neural network for the extracted feature indexes in Japanese texts, we evaluated identification performances for the three groups. As a result, high accuracy of personal identification was confirmed in both methods, in proportion to the typing level of the group.

Human Relations Class. A Syllabus.

ERIC Educational Resources Information Center

Guillen, Mary A.

A junior high level human relations class develops human interaction and oral communication skills. A week-by-week syllabus contains the following components: introduction of the students to each other and to the principles of body language, transactional analysis, and group interaction; behavior contracts; group dynamics topics and exercises;…

Dynamical Origins of Stereotypy: Relation of Postural Movements during Sitting to Stereotyped Movements during Body-Rocking

ERIC Educational Resources Information Center

Newell, Karl M.; Bodfish, James W.

2007-01-01

The relation between the movement dynamic properties of sitting still and of seated body-rocking in adults with stereotyped movement disorder and mental retardation and a contrast group of typically developing age-matched adults was examined. Continuous measurement of sequential displacements in center-of-pressure was made using a force platform…

Enhancing Learners' Emotions in an L2 Context through Emotionalized Dynamic Assessment

ERIC Educational Resources Information Center

Abdolrezapour, Parisa; Tavakoli, Mansoor; Ketabi, Saeed

2013-01-01

The aim of this study was to gain more in-depth understanding of students' emotions in an EFL context by applying dynamic assessment (DA) procedures to the development of learners' emotional intelligence. The study with 50 intermediate learners aged 12-15 used three modalities: a control group, which was taught under institute's normal procedures;…

Geodynamics Branch research report, 1982

NASA Technical Reports Server (NTRS)

Kahn, W. D. (Editor); Cohen, S. C. (Editor)

1983-01-01

The research program of the Geodynamics Branch is summarized. The research activities cover a broad spectrum of geoscience disciplines including space geodesy, geopotential field modeling, tectonophysics, and dynamic oceanography. The NASA programs which are supported by the work described include the Geodynamics and Ocean Programs, the Crustal Dynamics Project, the proposed Ocean Topography Experiment (TOPEX) and Geopotential Research Mission. The individual papers are grouped into chapters on Crustal Movements, Global Earth Dynamics, Gravity Field Model Development, Sea Surface Topography, and Advanced Studies.

Joint Loads and Cartilage Stress in Intact Joints of Military Transtibial Amputees: Enhancing Quality of Life

DTIC Science & Technology

2017-04-01

crosstalk); analysis of tested subjects underway. 4) Developed analytical methods to obtain knee joint loads using EMG-driven inverse dynamics; analysis of...13/2018. Completion %: 40. Task 1.3: EMG-driven inverse dynamic (ID) analyses with OpenSim for amputee and control group subjects. Target date: 1...predicted by EMG-driven inverse dynamics. Two-three conference papers are being prepared for submission in February 2017. Other achievements. None

Quantifying uncertainty due to fission-fusion dynamics as a component of social complexity.

PubMed

Ramos-Fernandez, Gabriel; King, Andrew J; Beehner, Jacinta C; Bergman, Thore J; Crofoot, Margaret C; Di Fiore, Anthony; Lehmann, Julia; Schaffner, Colleen M; Snyder-Mackler, Noah; Zuberbühler, Klaus; Aureli, Filippo; Boyer, Denis

2018-05-30

Groups of animals (including humans) may show flexible grouping patterns, in which temporary aggregations or subgroups come together and split, changing composition over short temporal scales, (i.e. fission and fusion). A high degree of fission-fusion dynamics may constrain the regulation of social relationships, introducing uncertainty in interactions between group members. Here we use Shannon's entropy to quantify the predictability of subgroup composition for three species known to differ in the way their subgroups come together and split over time: spider monkeys ( Ateles geoffroyi ), chimpanzees ( Pan troglodytes ) and geladas ( Theropithecus gelada ). We formulate a random expectation of entropy that considers subgroup size variation and sample size, against which the observed entropy in subgroup composition can be compared. Using the theory of set partitioning, we also develop a method to estimate the number of subgroups that the group is likely to be divided into, based on the composition and size of single focal subgroups. Our results indicate that Shannon's entropy and the estimated number of subgroups present at a given time provide quantitative metrics of uncertainty in the social environment (within which social relationships must be regulated) for groups with different degrees of fission-fusion dynamics. These metrics also represent an indirect quantification of the cognitive challenges posed by socially dynamic environments. Overall, our novel methodological approach provides new insight for understanding the evolution of social complexity and the mechanisms to cope with the uncertainty that results from fission-fusion dynamics. © 2017 The Author(s).

Hybrid Instrumentation in Lumbar Spinal Fusion

PubMed Central

Danyali, Reza; Kueny, Rebecca; Huber, Gerd; Reichl, Michael; Richter, Alexander; Niemeyer, Thomas; Morlock, Michael; Püschel, Klaus; Übeyli, Hüseyin

2017-01-01

Study Design Ex vivo human cadaveric study. Objective The development or progression of adjacent segment disease (ASD) after spine stabilization and fusion is a major problem in spine surgery. Apart from optimal balancing of the sagittal profile, dynamic instrumentation is often suggested to prevent or impede ASD. Hybrid instrumentation is used to gain stabilization while allowing motion to avoid hypermobility in the adjacent segment. In this biomechanical study, the effects of two different hybrid instrumentations on human cadaver spines were evaluated and compared with a rigid instrumentation. Methods Eighteen human cadaver spines (T11–L5) were subdivided into three groups: rigid, dynamic, and hook comprising six spines each. Clinical parameters and initial mechanical characteristics were consistent among groups. All specimens received rigid fixation from L3–L5 followed by application of a free bending load of extension and flexion. The range of motion (ROM) for every segment was evaluated. For the rigid group, further rigid fixation from L1–L5 was applied. A dynamic Elaspine system (Spinelab AG, Winterthur, Switzerland) was applied from L1 to L3 for the dynamic group, and the hook group was instrumented with additional laminar hooks at L1–L3. ROM was then evaluated again. Results There was no significant difference in ROM among the three instrumentation techniques. Conclusion Based on this data, the intended advantage of a hybrid or dynamic instrumentation might not be achieved. PMID:28451509

A Multi-layer Dynamic Model for Coordination Based Group Decision Making in Water Resource Allocation and Scheduling

NASA Astrophysics Data System (ADS)

Huang, Wei; Zhang, Xingnan; Li, Chenming; Wang, Jianying

Management of group decision-making is an important issue in water source management development. In order to overcome the defects in lacking of effective communication and cooperation in the existing decision-making models, this paper proposes a multi-layer dynamic model for coordination in water resource allocation and scheduling based group decision making. By introducing the scheme-recognized cooperative satisfaction index and scheme-adjusted rationality index, the proposed model can solve the problem of poor convergence of multi-round decision-making process in water resource allocation and scheduling. Furthermore, the problem about coordination of limited resources-based group decision-making process can be solved based on the effectiveness of distance-based group of conflict resolution. The simulation results show that the proposed model has better convergence than the existing models.

A Study of Group Dynamics in Educational Leadership Cohort and Non-Cohort Groups

ERIC Educational Resources Information Center

Greenlee, Bobbie J.; Karanxha, Zorka

2010-01-01

The purpose of this study was to examine group dynamics of educational leadership students in cohorts and make comparisons with the group dynamics characteristics of non-cohort students. Cohorts have emerged as dynamic and adaptive entities with attendant group dynamic processes that shape collective learning and action. Cohort (n=42) and…

Dynamics of Change in Research Work: Constructing a New Research Area in a Research Group.

ERIC Educational Resources Information Center

Saari, Eveliina; Miettinen, Reijo

2001-01-01

Studies how an aerosol technology research group constructed a research agenda for itself and how its activity was changed in the process. Analyzes the development of the production of ultrafine particles and employs the concept of mediated activity. (Contains 29 references.) (DDR)

MODELING THE DYNAMICS OF THREE FUNCTIONAL GROUPS OF MACROALGAE IN TROPICAL SEAGRASS HABITATS. (R828677C004)

EPA Science Inventory

A model of three functional groups of macroalgae, drift algae, rhizophytic calcareous algae, and seagrass epiphytes, was developed to complement an existing seagrass production model for tropical habitats dominated by Thalassia testudinum (Turtle-grass). The current modeling e...

The dynamic development of gender variability.

PubMed

Fausto-Sterling, Anne

2012-01-01

We diagram and discuss theories of gender identity development espoused by the clinical groups represented in this special issue. We contend that theories of origin relate importantly to clinical practice, and argue that the existing clinical theories are under-developed. Therefore, we develop a dynamic systems framework for gender identity development. Specifically, we suggest that critical aspects of presymbolic gender embodiment occur during infancy as part of the synchronous interplay of caregiver-infant dyads. By 18 months, a transition to symbolic representation and the beginning of an internalization of a sense of gender can be detected and consolidation is quite evident by 3 years of age. We conclude by suggesting empirical studies that could expand and test this framework. With the belief that better, more explicit developmental theory can improve clinical practice, we urge that clinicians take a dynamic developmental view of gender identity formation into account.

The System Dynamics Model for Development of Organic Agriculture

NASA Astrophysics Data System (ADS)

Rozman, Črtomir; Škraba, Andrej; Kljajić, Miroljub; Pažek, Karmen; Bavec, Martina; Bavec, Franci

2008-10-01

Organic agriculture is the highest environmentally valuable agricultural system, and has strategic importance at national level that goes beyond the interests of agricultural sector. In this paper we address development of organic farming simulation model based on a system dynamics methodology (SD). The system incorporates relevant variables, which affect the development of the organic farming. The group decision support system (GDSS) was used in order to identify most relevant variables for construction of causal loop diagram and further model development. The model seeks answers to strategic questions related to the level of organically utilized area, levels of production and crop selection in a long term dynamic context and will be used for simulation of different policy scenarios for organic farming and their impact on economic and environmental parameters of organic production at an aggregate level.

Analysis of stationary and dynamic factors affecting highway accident occurrence: A dynamic correlated grouped random parameters binary logit approach.

PubMed

Fountas, Grigorios; Sarwar, Md Tawfiq; Anastasopoulos, Panagiotis Ch; Blatt, Alan; Majka, Kevin

2018-04-01

Traditional accident analysis typically explores non-time-varying (stationary) factors that affect accident occurrence on roadway segments. However, the impact of time-varying (dynamic) factors is not thoroughly investigated. This paper seeks to simultaneously identify pre-crash stationary and dynamic factors of accident occurrence, while accounting for unobserved heterogeneity. Using highly disaggregate information for the potential dynamic factors, and aggregate data for the traditional stationary elements, a dynamic binary random parameters (mixed) logit framework is employed. With this approach, the dynamic nature of weather-related, and driving- and pavement-condition information is jointly investigated with traditional roadway geometric and traffic characteristics. To additionally account for the combined effect of the dynamic and stationary factors on the accident occurrence, the developed random parameters logit framework allows for possible correlations among the random parameters. The analysis is based on crash and non-crash observations between 2011 and 2013, drawn from urban and rural highway segments in the state of Washington. The findings show that the proposed methodological framework can account for both stationary and dynamic factors affecting accident occurrence probabilities, for panel effects, for unobserved heterogeneity through the use of random parameters, and for possible correlation among the latter. The comparative evaluation among the correlated grouped random parameters, the uncorrelated random parameters logit models, and their fixed parameters logit counterpart, demonstrate the potential of the random parameters modeling, in general, and the benefits of the correlated grouped random parameters approach, specifically, in terms of statistical fit and explanatory power. Published by Elsevier Ltd.

Reverse engineering a social agent-based hidden markov model--visage.

PubMed

Chen, Hung-Ching Justin; Goldberg, Mark; Magdon-Ismail, Malik; Wallace, William A

2008-12-01

We present a machine learning approach to discover the agent dynamics that drives the evolution of the social groups in a community. We set up the problem by introducing an agent-based hidden Markov model for the agent dynamics: an agent's actions are determined by micro-laws. Nonetheless, We learn the agent dynamics from the observed communications without knowing state transitions. Our approach is to identify the appropriate micro-laws corresponding to an identification of the appropriate parameters in the model. The model identification problem is then formulated as a mixed optimization problem. To solve the problem, we develop a multistage learning process for determining the group structure, the group evolution, and the micro-laws of a community based on the observed set of communications among actors, without knowing the semantic contents. Finally, to test the quality of our approximations and the feasibility of the approach, we present the results of extensive experiments on synthetic data as well as the results on real communities, such as Enron email and Movie newsgroups. Insight into agent dynamics helps us understand the driving forces behind social evolution.

Experimental study on small group behavior and crowd dynamics in a tall office building evacuation

NASA Astrophysics Data System (ADS)

Ma, Yaping; Li, Lihua; Zhang, Hui; Chen, Tao

2017-05-01

It is well known that a large percentage of occupants in a building are evacuated together with their friends, families, and officemates, especially in China. Small group behaviors are therefore critical for crowd movement. This paper aims to study the crowd dynamic considering different social relations and the impacts of small groups on crowd dynamics in emergency evacuation. Three experiments are conducted in an 11-storey office building. In the first two experiments, all participants are classmates and know each other well. They are evacuated as individuals or pairs. In the third experiment, social relations among the participants are complex. Participants consist of 8 families, 6 lovers and several individuals. Space-time features, speed characteristics and density-speed relations for each experiment are analyzed and compared. Results conclude that small group behaviors can make positive impacts on crowd dynamics when evacuees know each other and are cooperative. This conclusion is also testified by four verified experiments. In the third experiment, speeds of evacuees are lowest. Small groups form automatically with the presence of intimate social relations. Small groups in this experiment slow down the average speed of the crowd and make disturbance on the crowd flow. Small groups in this case make negative impacts on the movement of the crowd. It is because that evacuees do not know each other and they are competitive to each other. Characteristics of different types of small groups are also investigated. Experimental data can provide foundational parameters for evacuation model development and are helpful for building designers.

An overview of the dynamics of the Volcanic Paroxysmal Explosive Activity, and related seismicity, at andesitic and dacitic volcanoes (1960-2010)

NASA Astrophysics Data System (ADS)

Zobin, Vyacheslav M.

2018-05-01

Understanding volcanic paroxysmal explosive activity requires the knowledge of many associated processes. An overview of the dynamics of paroxysmal explosive eruptions (PEEs) at andesitic and dacitic volcanoes occurring between 1960 and 2010 is presented here. This overview is based mainly on a description of the pre-eruptive and eruptive events, as well as on the related seismic measurements. The selected eruptions are grouped according to their Volcanic Explosivity Index (VEI). A first group includes three eruptions of VEI 5-6 (Mount St. Helens, 1980; El Chichón, 1982, and Pinatubo, 1991) and a second group includes three eruptions of VEI 3 (Usu volcano, 1977; Soufriere Hills Volcano (SHV), 1996, and Volcán de Colima, 2005). The PEEs of the first group have similarity in their developments that allows to propose a 5-stage scheme of their dynamics process. Between these stages are: long (more than 120 years) period of quiescence (stage 1), preliminary volcano-tectonic (VT) earthquake swarm (stage 2), period of phreatic explosions (stage 3) and then, PEE appearance (stage 4). It was shown also that the PEEs of this group during their Plinian stage "triggered" the earthquake sequences beneath the volcanic structures with the maximum magnitude of earthquakes proportional to the volume of ejecta of PEEs (stage 5). Three discussed PEEs of the second group with lower VEI developed in more individual styles, not keeping within any general scheme. Among these, one PEE (SHV) may be considered as partly following in development to the PEEs of the first group, having stages 1, 3 and 4. The PEEs of Usu volcano and of Volcán de Colima had no preliminary long-term stages of quiescence. The PEE at Usu volcano came just at the end of the preceding short swarm of VT earthquakes. At Volcán de Colima, no preceding swarm of VT occurred. This absence of any regularity in development of lower VEI eruptions may refer, among other reasons, to different conditions of opening of the magmatic conduit during these eruptions.

SIAM conference on applications of dynamical systems

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

Not Available

1992-01-01

A conference (Oct.15--19, 1992, Snowbird, Utah; sponsored by SIAM (Society for Industrial and Applied Mathematics) Activity Group on Dynamical Systems) was held that highlighted recent developments in applied dynamical systems. The main lectures and minisymposia covered theory about chaotic motion, applications in high energy physics and heart fibrillations, turbulent motion, Henon map and attractor, integrable problems in classical physics, pattern formation in chemical reactions, etc. The conference fostered an exchange between mathematicians working on theoretical issues of modern dynamical systems and applied scientists. This two-part document contains abstracts, conference program, and an author index.

SIAM conference on applications of dynamical systems. Abstracts and author index

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

Not Available

1992-12-31

A conference (Oct.15--19, 1992, Snowbird, Utah; sponsored by SIAM (Society for Industrial and Applied Mathematics) Activity Group on Dynamical Systems) was held that highlighted recent developments in applied dynamical systems. The main lectures and minisymposia covered theory about chaotic motion, applications in high energy physics and heart fibrillations, turbulent motion, Henon map and attractor, integrable problems in classical physics, pattern formation in chemical reactions, etc. The conference fostered an exchange between mathematicians working on theoretical issues of modern dynamical systems and applied scientists. This two-part document contains abstracts, conference program, and an author index.

Development of high-temperature Kolsky compression bar techniques for recrystallization investigation

NASA Astrophysics Data System (ADS)

Song, B.; Antoun, B. R.; Boston, M.

2012-05-01

We modified the design originally developed by Kuokkala's group to develop an automated high-temperature Kolsky compression bar for characterizing high-rate properties of 304L stainless steel at elevated temperatures. Additional features have been implemented to this high-temperature Kolsky compression bar for recrystallization investigation. The new features ensure a single loading on the specimen and precise time and temperature control for quenching to the specimen after dynamic loading. Dynamic compressive stress-strain curves of 304L stainless steel were obtained at 21, 204, 427, 649, and 871 °C (or 70, 400, 800, 1200, and 1600 °F) at the same constant strain rate of 332 s-1. The specimen subjected to specific time and temperature control for quenching after a single dynamic loading was preserved for investigating microstructure recrystallization.

Trophic groups and modules: two levels of group detection in food webs.

PubMed

Gauzens, Benoit; Thébault, Elisa; Lacroix, Gérard; Legendre, Stéphane

2015-05-06

Within food webs, species can be partitioned into groups according to various criteria. Two notions have received particular attention: trophic groups (TGs), which have been used for decades in the ecological literature, and more recently, modules. The relationship between these two group concepts remains unknown in empirical food webs. While recent developments in network theory have led to efficient methods for detecting modules in food webs, the determination of TGs (groups of species that are functionally similar) is largely based on subjective expert knowledge. We develop a novel algorithm for TG detection. We apply this method to empirical food webs and show that aggregation into TGs allows for the simplification of food webs while preserving their information content. Furthermore, we reveal a two-level hierarchical structure where modules partition food webs into large bottom-top trophic pathways, whereas TGs further partition these pathways into groups of species with similar trophic connections. This provides new perspectives for the study of dynamical and functional consequences of food-web structure, bridging topological and dynamical analysis. TGs have a clear ecological meaning and are found to provide a trade-off between network complexity and information loss. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

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

Not Available

As the search for oil and gas continues into deeper and deeper waters, semisubmersibles and dynamically positioned vessels are becoming larger and more sophisticated. Efforts to reduce downtime resulting from foul weather are apparent in some new rigs designed to have improved motion characteristics. New offshore drilling rigs described include l) a buoy-shaped semisubmersible, the Big Bouy 6000 from the Trosvik Group of Norway, 2) a dynamically positioned drillship to be operated by the Dutch firm Neddrill, 3) Parker Drilling Co.'s helicopter-transportable platform rig, rated for 20,000 ft, 4) a dynamically positioned semisubmersible developed by French drilling contractor Forex Neptune,more » and 5) a reinforced-concrete semisubmersible, the Condrill concept, developed by Norwegian contractor A/S Hoyer-Ellefsen.« less

Dynamic autophagic activity affected the development of thoracic aortic dissection by regulating functional properties of smooth muscle cells

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

Wang, Yang; Zhao, Zhi-Min; Zhang, Guan-Xin

The aortic medial degeneration is the key histopathologic feature of Thoracic aortic dissection (TAD). The aim of this study was to identify the change of autophagic activity in the aortic wall during TAD development, and to explore the roles of autophagy on regulating functional properties of smooth muscle cells (SMCs). Firstly, compared with control group (n = 11), the increased expression of autophagic markers Beclin1 and LC3 was detected in the aortic wall from TAD group (n = 23) by immunochemistry and western blot. We found that more autophagic vacuoles were present in the aortic wall of TAD patients using Transmission electron microscopy. Next,more » autophagic activity was examined in AD mice model established by β-aminopropionitrile fumarate (BAPN) and angiotensin II. Immunochemistry proved that autophagic activity was dynamically changed during AD development. Beclin1 and LC3 were detected up-regulated in the aortic wall in the second week after BAPN feeding, earlier than the fragmentation or loss of elastic fibers. When AD occurred in the 4th week, the expression of Beclin1 and LC3 began to decrease, but still higher than the control. Furthermore, autophagy was found to inhibit starvation-induced apoptosis of SMCs. Meanwhile, blockage of autophagy could suppress PDGF-induced phenotypic switch of SMCs. Taken together, autophagic activity was dynamically changed in the aortic wall during TAD development. The abnormal autophagy could regulate the functional properties of aortic SMCs, which might be the potential pathogenesis of TAD. - Highlights: • Autophagy is up-regulated in aorta wall from thoracic aorta dissection (TAD) patient. • Autophagic activity is dynamically changed during TAD development. • Dynamically change of autophagy is associated with pathological process of TAD. • Autophagy participate in the development of TAD by regulating function of SMCs.« less

A new data-driven model for post-transplant antibody dynamics in high risk kidney transplantation.

PubMed

Zhang, Yan; Briggs, David; Lowe, David; Mitchell, Daniel; Daga, Sunil; Krishnan, Nithya; Higgins, Robert; Khovanova, Natasha

2017-02-01

The dynamics of donor specific human leukocyte antigen antibodies during early stage after kidney transplantation are of great clinical interest as these antibodies are considered to be associated with short and long term clinical outcomes. The limited number of antibody time series and their diverse patterns have made the task of modelling difficult. Focusing on one typical post-transplant dynamic pattern with rapid falls and stable settling levels, a novel data-driven model has been developed for the first time. A variational Bayesian inference method has been applied to select the best model and learn its parameters for 39 time series from two groups of graft recipients, i.e. patients with and without acute antibody-mediated rejection (AMR) episodes. Linear and nonlinear dynamic models of different order were attempted to fit the time series, and the third order linear model provided the best description of the common features in both groups. Both deterministic and stochastic parameters are found to be significantly different in the AMR and no-AMR groups showing that the time series in the AMR group have significantly higher frequency of oscillations and faster dissipation rates. This research may potentially lead to better understanding of the immunological mechanisms involved in kidney transplantation. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Group dynamics for the acquisition of competences in Project Management

NASA Astrophysics Data System (ADS)

Taguas, E. V.; Aguilar, M. C.; Castillo, C.; Polo, M. J.; Pérez, R.

2012-04-01

The Bologna Process promotes European citizens' employability from teaching fields in the University which implies the design of activities addressed to the development of skills for the labor market and engagement of employers. This work has been conceived for improving the formation of Engineering Project Management through group dynamics focused on: 1) the use of the creativity for solving problems; 2) promoting leadership capacities and social skills in multidisciplinary/multicultural work groups; 3) the ethical, social and environmental compromise; 4) the continuous learning. Different types of activities were designed: short activities of 15-30 minutes where fragments of books or songs are presented and discussed and long activities (2 h) where groups of students take different roles for solving common problems and situations within the Engineering Projects context. An electronic book with the content of the dynamics and the material for the students has been carried out. A sample of 20 students of Electronic Engineering degree which had participated at least in two dynamics, evaluated the utility for improving their formation in Engineering Project Management with a mark of 8.2 (scale 0-10, standard deviation equal to 0.9). On the other hand, the teachers observed how this type of work, promotes the interdisciplinary training and the acquisition of social skills, usually not-included in the objectives of the subjects.

Interacting Learning Processes during Skill Acquisition: Learning to control with gradually changing system dynamics.

PubMed

Ludolph, Nicolas; Giese, Martin A; Ilg, Winfried

2017-10-16

There is increasing evidence that sensorimotor learning under real-life conditions relies on a composition of several learning processes. Nevertheless, most studies examine learning behaviour in relation to one specific learning mechanism. In this study, we examined the interaction between reward-based skill acquisition and motor adaptation to changes of object dynamics. Thirty healthy subjects, split into two groups, acquired the skill of balancing a pole on a cart in virtual reality. In one group, we gradually increased the gravity, making the task easier in the beginning and more difficult towards the end. In the second group, subjects had to acquire the skill on the maximum, most difficult gravity level. We hypothesized that the gradual increase in gravity during skill acquisition supports learning despite the necessary adjustments to changes in cart-pole dynamics. We found that the gradual group benefits from the slow increment, although overall improvement was interrupted by the changes in gravity and resulting system dynamics, which caused short-term degradations in performance and timing of actions. In conclusion, our results deliver evidence for an interaction of reward-based skill acquisition and motor adaptation processes, which indicates the importance of both processes for the development of optimized skill acquisition schedules.

Immunity-Based Optimal Estimation Approach for a New Real Time Group Elevator Dynamic Control Application for Energy and Time Saving

PubMed Central

Baygin, Mehmet; Karakose, Mehmet

2013-01-01

Nowadays, the increasing use of group elevator control systems owing to increasing building heights makes the development of high-performance algorithms necessary in terms of time and energy saving. Although there are many studies in the literature about this topic, they are still not effective enough because they are not able to evaluate all features of system. In this paper, a new approach of immune system-based optimal estimate is studied for dynamic control of group elevator systems. The method is mainly based on estimation of optimal way by optimizing all calls with genetic, immune system and DNA computing algorithms, and it is evaluated with a fuzzy system. The system has a dynamic feature in terms of the situation of calls and the option of the most appropriate algorithm, and it also adaptively works in terms of parameters such as the number of floors and cabins. This new approach which provides both time and energy saving was carried out in real time. The experimental results comparatively demonstrate the effects of method. With dynamic and adaptive control approach in this study carried out, a significant progress on group elevator control systems has been achieved in terms of time and energy efficiency according to traditional methods. PMID:23935433

S-Lagrangian dynamics of many-body systems and behavior of social groups: Dominance and hierarchy formation

NASA Astrophysics Data System (ADS)

Sandler, U.

2017-11-01

In this paper, we extend our generalized Lagrangian dynamics (i.e., S-Lagrangian dynamics, which can be applied equally to physical and non-physical systems as per Sandler (2014)) to many-body systems. Unlike common Lagrangian dynamics, this is not a trivial task. For many-body systems with S-dependent Lagrangians, the Lagrangian and the corresponding Hamiltonian or energy become vector functions, conjugated momenta become second-order tensors, and the system inevitably develops a hierarchical structure, even if all bodies initially have similar status and Lagrangians. As an application of our theory, we consider dominance and hierarchy formation, which is present in almost all communities of living species. As a biological basis for this application, we assume that the primary motivation of a groups activity is to attempt to cope with stress arising as pressure from the environment and from intrinsic unmet needs of individuals. It has been shown that the S-Lagrangian approach to a group's evolution naturally leads to formation of linear or despotic dominance hierarchies, depending on differences between individuals in coping with stress. That is, individuals that cope more readily with stress take leadership roles during the evolution. Experimental results in animal groups which support our assumption and findings are considered.

Small Group Dynamics and the Watergate Coverup: A Case Study of Groupthink.

ERIC Educational Resources Information Center

Cline, Rebecca J.

The decisions President Richard Nixon and his closest advisors made in the Watergate coverup were products of what Irving Janis calls "groupthink." Groupthink, a type of decision-making emphasizing unanimity over objective evaluation, develops when the decision makers (1) form a group of marked cohesiveness, (2) insulate themselves from…

Proline-based chiral stationary phases: a molecular dynamics study of the interfacial structure.

PubMed

Ashtari, M; Cann, N M

2011-09-16

Proline chains have generated considerable interest as a possible basis for new selectors in chiral chromatography. In this article, we employ molecular dynamics simulations to examine the interfacial structure of two diproline chiral selectors, one with a terminal trimethylacetyl group and one with a terminal t-butyl carbamate group. The solvents consist of a relatively apolar n-hexane/2-propanol and a polar water/methanol mixture. We begin with electronic structure calculations for the two chiral selectors to assess the energetics of conformational changes, particularly along the backbone where the amide bonds can alternate between cis and trans conformations. Force fields have been developed for the two selectors, based on these ab initio calculations. Molecular dynamics simulations of the selective interfaces are performed to examine the preferred backbone conformations, as a function of end-group and solvent. The full chiral surface includes the diproline selectors, trimethylsilyl end-caps, and silanol groups. Connection is made with selectivity measurements on these interfaces, where significant differences are observed between these two very similar selectors. Copyright © 2011 Elsevier B.V. All rights reserved.

Coherence and incoherence collective behavior in financial market

NASA Astrophysics Data System (ADS)

Zhao, Shangmei; Xie, Qiuchao; Lu, Qing; Jiang, Xin; Chen, Wei

2015-10-01

Financial markets have been extensively studied as highly complex evolving systems. In this paper, we quantify financial price fluctuations through a coupled dynamical system composed of phase oscillators. We find that a Financial Coherence and Incoherence (FCI) coexistence collective behavior emerges as the system evolves into the stable state, in which the stocks split into two groups: one is represented by coherent, phase-locked oscillators, the other is composed of incoherent, drifting oscillators. It is demonstrated that the size of the coherent stock groups fluctuates during the economic periods according to real-world financial instabilities or shocks. Further, we introduce the coherent characteristic matrix to characterize the involvement dynamics of stocks in the coherent groups. Clustering results on the matrix provides a novel manifestation of the correlations among stocks in the economic periods. Our analysis for components of the groups is consistent with the Global Industry Classification Standard (GICS) classification and can also figure out features for newly developed industries. These results can provide potentially implications on characterizing the inner dynamical structure of financial markets and making optimal investment into tragedies.

The group dynamics of women's self-defense training.

PubMed

Brecklin, Leanne R; Middendorf, Rena K

2014-03-01

The current study examines the role of group interaction in a women's self-defense class. Study methods included individual interviews with women who had completed a college-based women-only self-defense course as well as supplemental observation of group behavior during a mock "attack" simulation class. The unique relationship that develops among women's self-defense classmates seems to improve overall learning and performance due to the group collaboration and vicarious experiences. Results demonstrated that women's self-defense courses offer participants a beneficial and supportive group atmosphere.

Observation of Entangled States of a Fully Controlled 20-Qubit System

NASA Astrophysics Data System (ADS)

Friis, Nicolai; Marty, Oliver; Maier, Christine; Hempel, Cornelius; Holzäpfel, Milan; Jurcevic, Petar; Plenio, Martin B.; Huber, Marcus; Roos, Christian; Blatt, Rainer; Lanyon, Ben

2018-04-01

We generate and characterize entangled states of a register of 20 individually controlled qubits, where each qubit is encoded into the electronic state of a trapped atomic ion. Entanglement is generated amongst the qubits during the out-of-equilibrium dynamics of an Ising-type Hamiltonian, engineered via laser fields. Since the qubit-qubit interactions decay with distance, entanglement is generated at early times predominantly between neighboring groups of qubits. We characterize entanglement between these groups by designing and applying witnesses for genuine multipartite entanglement. Our results show that, during the dynamical evolution, all neighboring qubit pairs, triplets, most quadruplets, and some quintuplets simultaneously develop genuine multipartite entanglement. Witnessing genuine multipartite entanglement in larger groups of qubits in our system remains an open challenge.

Biological Dynamics Markup Language (BDML): an open format for representing quantitative biological dynamics data

PubMed Central

Kyoda, Koji; Tohsato, Yukako; Ho, Kenneth H. L.; Onami, Shuichi

2015-01-01

Motivation: Recent progress in live-cell imaging and modeling techniques has resulted in generation of a large amount of quantitative data (from experimental measurements and computer simulations) on spatiotemporal dynamics of biological objects such as molecules, cells and organisms. Although many research groups have independently dedicated their efforts to developing software tools for visualizing and analyzing these data, these tools are often not compatible with each other because of different data formats. Results: We developed an open unified format, Biological Dynamics Markup Language (BDML; current version: 0.2), which provides a basic framework for representing quantitative biological dynamics data for objects ranging from molecules to cells to organisms. BDML is based on Extensible Markup Language (XML). Its advantages are machine and human readability and extensibility. BDML will improve the efficiency of development and evaluation of software tools for data visualization and analysis. Availability and implementation: A specification and a schema file for BDML are freely available online at http://ssbd.qbic.riken.jp/bdml/. Contact: sonami@riken.jp Supplementary Information: Supplementary data are available at Bioinformatics online. PMID:25414366

Biological Dynamics Markup Language (BDML): an open format for representing quantitative biological dynamics data.

PubMed

Kyoda, Koji; Tohsato, Yukako; Ho, Kenneth H L; Onami, Shuichi

2015-04-01

Recent progress in live-cell imaging and modeling techniques has resulted in generation of a large amount of quantitative data (from experimental measurements and computer simulations) on spatiotemporal dynamics of biological objects such as molecules, cells and organisms. Although many research groups have independently dedicated their efforts to developing software tools for visualizing and analyzing these data, these tools are often not compatible with each other because of different data formats. We developed an open unified format, Biological Dynamics Markup Language (BDML; current version: 0.2), which provides a basic framework for representing quantitative biological dynamics data for objects ranging from molecules to cells to organisms. BDML is based on Extensible Markup Language (XML). Its advantages are machine and human readability and extensibility. BDML will improve the efficiency of development and evaluation of software tools for data visualization and analysis. A specification and a schema file for BDML are freely available online at http://ssbd.qbic.riken.jp/bdml/. Supplementary data are available at Bioinformatics online. © The Author 2014. Published by Oxford University Press.

Teachers' Attunement to Students' Peer Group Affiliations as a Source of Improved Student Experiences of the School Social-Affective Context following the Middle School Transition

ERIC Educational Resources Information Center

Hamm, Jill V.; Farmer, Thomas W.; Dadisman, Kimberly; Gravelle, Maggie; Murray, Allen R.

2011-01-01

A randomized control trial examined the impact of a professional development program on rural teachers' attunement to student social dynamics, and the influence of teacher attunement on students' school experiences. In intervention schools serving Latino and White rural early adolescents, teachers (N = 14) received training on social dynamics and…

Group dynamics and social interaction in a South Asian online learning forum for faculty development of medical teachers.

PubMed

Anshu; Sharma, M; Burdick, W P; Singh, T

2010-04-01

Group dynamics of online medical faculty development programs have not been analyzed and reported in literature. Knowledge of the types of content of posted messages will help to understand group dynamics and promote participation in an asynchronous learning environment. This paper assesses group dynamics and social interactivity in an online learning environment for medical teachers in the South Asian context. Participants of a medical education fellowship program conducted by the Foundation for Advancement of International Medical Education and Research (FAIMER) Regional Institute at Christian Medical College, Ludhiana (CMCL) in India interact on a listserv called the Mentoring-Learning Web (ML-Web). Monthly topics for online discussion are chosen by fellows through a standard tool called "multi-voting". Fellows volunteer to moderate sessions and direct the pace of the discussion. We analyzed the content and process of the discussion of one particular month. The emails were categorized as those that reflected cognitive presence (dealing with construction and exploration of knowledge), teacher presence (dealing with instructional material and learning resources), and social presence, or were administrative in nature. Social emails were further classified as: affective, cohesive and interactive. Social emails constituted one-third of the total emails. Another one-quarter of the emails dealt with sharing of resources and teacher presence, while cognitive emails comprised 36.2% of the total. More than half of the social emails were affective, while a little less than one-third were cohesive. Social posts are an inevitable part of online learning. These posts promote bonding between learners and contribute to better interaction and collaboration in online learning. Moderators should be aware of their presence and use them as tools to promote interactivity.

The Role of Family Income Dynamics in Predicting Trajectories of Internalizing and Externalizing Problems.

PubMed

Miller, Portia; Votruba-Drzal, Elizabeth

2017-04-01

Economic disparities in children's behavioral functioning have been observed in prior research. Yet, studies have ignored important perspectives from developmental psychopathology and have not delineated how aspects of income dynamics (i.e., cumulative family income versus income volatility) differentially relate to behavior problems. To address these limitations, the current study examined how both cumulative income and income volatility predict trajectories of children's internalizing and externalizing problems from kindergarten through fifth grade in a nationally representative sample of 10,900 children (51.4 % male). Results showed four distinct trajectories of internalizing problems and five distinct externalizing trajectories. Family income dynamics were related to trajectory group membership. Specifically, increased cumulative income decreased risk of membership in mid-increasing and mid-stable internalizing groups, and children whose families experienced multiple waves of income loss were 2.4 times as likely to be in the mid-increasing group instead of the low-stable group. With respect to externalizing, higher cumulative income increased the likelihood of belonging in the group exhibiting stably low externalizing problems. Experiencing income loss increased the risk of belonging in the trajectory group exhibiting chronically high externalizing behaviors. These results enhance our knowledge of the role of family income in the development of behavior problems.

The dynamic changes of vaginal microecosystem in patients with recurrent vulvovaginal candidiasis: a retrospective study of 800 patients.

PubMed

Yue, Xin-Ai; Chen, Ping; Tang, Yuanting; Wu, Xiuli; Hu, Zhengqiang

2015-12-01

Vaginal microecological environment is an important factor of recurrent vulvovaginal candidiasis (RVVC). This study was undertaken to investigate dynamic changes of vaginal microecosystem in patients with RVVC. Four hundred patients with VVC and 400 healthy women of reproductive age who admitted to the hospital from January 2012 to December 2013 were evaluated retrospectively. Vaginal microecological factors were evaluated before and after treatment until no recurrence, including vaginal cleanliness, white blood cells, Lactobacillus, Lactobacillus classification, bacteria density, flora diversity, Nugent scores, etc. The grouping was done according to the recurrence of the disease. Every time after treatment, the relapsing patients were defined as case group and the cured patients without recurrence were defined as control group. The differences in the results between the case and the control groups were analyzed by t test. With the development of RVVC, the ages of all case groups were lower than the corresponding control groups. In different stages of the disease, the bacteria density of the case groups and their corresponding control groups had no significant difference (P > 0.05). Most of the microecological indicators of the first occurring group were significantly different (P < 0.05) from that of the control group. In the recurrence groups, only a few indicators were significantly different from the control groups. The values of all vaginal microecological indicators (except Lactobacillus) of all case groups were higher than that of the control groups. The values of Lactobacillus of all RVVC case groups were lower than that of the RVVC control groups. There were vaginal microecological imbalances in all developing stages of RVVC. As for vaginal flora, diverse sorts changed to normal Lactobacillus dominantly with the development of RVVC. In the first occurrence of RVVC, after antifungal treatment, Lactobacillus is suggested to be timely supplemented to restore vaginal microecological balance.

Conversation, development, and gender: a study of changes in children's concepts of punishment.

PubMed

Leman, Patrick J; Björnberg, Marina

2010-01-01

One hundred thirty-three children, average age 9.58 years, were read vignettes describing a moral transgression and then discussed what would constitute a fair punishment. Children's gender influenced conversation dynamics (use of interruption and other simultaneous speech) but not conversation content (justifications for judgments). All children who engaged in conversation showed development in judgments after 8 weeks compared with a control (no interaction) group. However, there was no relation between conversation dynamics or content and development, or any effects of gender, on the developmental process. The benefits of peer collaboration were general rather than specific to the stimulus story.

The evaluation life cycle: a retrospective assessment of stages and phases of the circles of care initiative.

PubMed

Bess, Gary; Allen, James; Deters, Pamela B

2004-08-12

A life cycle metaphor characterizes the evolving relationship between the evaluator and program staff. This framework suggests that common developmental dynamics occur in roughly the same order across groups and settings. There are stage-specific dynamics that begin with Pre-History, which characterize the relationship between the grantees and evaluator. The stages are: (a) Pre-History, (b) Process, (c) Development, (d) Action, (e) Findings-Compilation, and (f) Transition. The common dynamics, expectations, and activities for each stage are discussed.

Experimental investigation of dynamic fragmentation of laser shock-loaded by soft recovery and X-ray radiography

NASA Astrophysics Data System (ADS)

Xin, Jianting; He, Weihua; Chu, Genbai; Gu, Yuqiu

2017-06-01

Dynamic fragmentation of metal under shock pressure is an important issue for both fundamental science and practical applications. And in recent decades, laser provides a promising shock loading technique for investigating the process of dynamic fragmentation under extreme condition application of high strain rate. Our group has performed experimental investigation of dynamic fragmentation under laser shock loading by soft recovery and X-ray radiography at SGC / ó prototype laser facility. The fragments under different loading pressures were recovered by PMP foam and analyzed by X-ray micro-tomography and the improved watershed method. The experiment result showed that the bilinear exponential distribution is more appropriate for representing the fragment size distribution. We also developed X-ray radiography technique. Owing to its inherent advantage over shadowgraph technique, X-ray radiography can potentially determine quantitatively material densities by measuring the X-ray transmission. Our group investigated dynamic process of microjetting by X-ray radiography technique, the recorded radiographic images show clear microjetting from the triangular grooves in the free surface of tin sample.

[Perception of the transition to motherhood: a phenomenological study in the Barcelona region].

PubMed

Berlanga Fernández, Sofía; Vizcaya-Moreno, María Flores; Pérez-Cañaveras, Rosa María

2013-10-01

To describe needs and experiences of mothers with children under one year old, to identify the factors that hinder the transition to motherhood, and to design the content of a health promotion program to develop motherhood support group sessions. A qualitative study with a phenomenological approach. Eight Primary Care Centres in the province of Barcelona, between July 2011 and July 2012. A total of 21 mothers participating in group dynamics maternity support: All of them participated in interviews and 8 in focus group. Semi-structured interviews were used in a purposive sample. The transcriptions were analysed by structure (latent content analysis) and content (manifest content analysis), with different categories being obtained. The participants in the study defined the construct of motherhood around three categories: Changes in lifestyle, feelings and perceptions. They identified as the most stressful times; «the new role», «changes in the partner relationship», «feelings», «experiences of pregnancy and childbirth», «idealisation», «lack of support», «crying», «colic», «read the signs of the child», «bath», «rest», «contradictory opinions», «learning», and «acquisition of new skills». They highlighted, as key topics for group dynamics, feeding, development, affective relationship, maternal confidence, fathers participation, family role, emotional, rest, massage, bath, accident prevention, colic, first aid, childcare, resources, and vaccines. Dynamic groups should be contextualised according to the perceived needs of the mothers, and other family members should be allowed to participate. Copyright © 2012 Elsevier España, S.L. All rights reserved.

Academic Excellence/Economic Development Working Group Progress Report to the Board

ERIC Educational Resources Information Center

Oregon University System, 2004

2004-01-01

A knowledge economy produces new knowledge; transforms knowledge into innovative products, processes, and services; moves innovations into the marketplace; and ultimately, develops new markets. It is global in perspective, collaborative in process, and dynamic in its responsiveness to changing conditions. Most important, it is fed by a healthy…

78 FR 43925 - Solicitation for a Cooperative Agreement-Executive Excellence a Training and Development Program...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-22

... leadership skill building, exposure to ethical and value based issues, self-awareness, strategic thinking... development, communication, feedback, Type Theory, emotional intelligence, self awareness and group dynamics... Requirements: Documents or other media that are produced under this award must follow these guidelines: Prior...

Student leadership in small group science inquiry

NASA Astrophysics Data System (ADS)

Oliveira, Alandeom W.; Boz, Umit; Broadwell, George A.; Sadler, Troy D.

2014-09-01

Background: Science educators have sought to structure collaborative inquiry learning through the assignment of static group roles. This structural approach to student grouping oversimplifies the complexities of peer collaboration and overlooks the highly dynamic nature of group activity. Purpose: This study addresses this issue of oversimplification of group dynamics by examining the social leadership structures that emerge in small student groups during science inquiry. Sample: Two small student groups investigating the burning of a candle under a jar participated in this study. Design and method: We used a mixed-method research approach that combined computational discourse analysis (computational quantification of social aspects of small group discussions) with microethnography (qualitative, in-depth examination of group discussions). Results: While in one group social leadership was decentralized (i.e., students shared control over topics and tasks), the second group was dominated by a male student (centralized social leadership). Further, decentralized social leadership was found to be paralleled by higher levels of student cognitive engagement. Conclusions: It is argued that computational discourse analysis can provide science educators with a powerful means of developing pedagogical models of collaborative science learning that take into account the emergent nature of group structures and highly fluid nature of student collaboration.

Mediated Group Development and Dynamics: An Examination of Video Chatting, Twitter, and Facebook in Group Assignments

ERIC Educational Resources Information Center

Frisby, Brandi N.; Kaufmann, Renee; Beck, Anna-Carrie

2016-01-01

Instructors incorporate technological tools into the classroom to address short attention spans, appeal to technologically savvy students, and to increase engagement. This study used both quantitative descriptive and qualitative embedded assessment data to examine the use of three popular tools (i.e. Twitter, Facebook, and video chatting) in…

A multi-segment foot model based on anatomically registered technical coordinate systems: method repeatability and sensitivity in pediatric planovalgus feet.

PubMed

Saraswat, Prabhav; MacWilliams, Bruce A; Davis, Roy B; D'Astous, Jacques L

2013-01-01

Several multisegment foot models have been proposed and some have been used to study foot pathologies. These models have been tested and validated on typically developed populations; however application of such models to feet with significant deformities presents an additional set of challenges. For the first time, in this study, a multisegment foot model is tested for repeatability in a population of children with symptomatic abnormal feet. The results from this population are compared to the same metrics collected from an age matched (8-14 years) typically developing population. The modified Shriners Hospitals for Children, Greenville (mSHCG) foot model was applied to ten typically developing children and eleven children with planovalgus feet by two clinicians. Five subjects in each group were retested by both clinicians after 4-6 weeks. Both intra-clinician and inter-clinician repeatability were evaluated using static and dynamic measures. A plaster mold method was used to quantify variability arising from marker placement error. Dynamic variability was measured by examining trial differences from the same subjects when multiple clinicians carried out the data collection multiple times. For hindfoot and forefoot angles, static and dynamic variability in both groups was found to be less than 4° and 6° respectively. The mSHCG model strategy of minimal reliance on anatomical markers for dynamic measures and inherent flexibility enabled by separate anatomical and technical coordinate systems resulted in a model equally repeatable in typically developing and planovalgus populations. Copyright © 2012 Elsevier B.V. All rights reserved.

Non-acute care facility ownership: if not you, who?

PubMed

Davis, J Michael

2007-01-01

Physician groups now face a dynamic medical real estate market that can provide an attractive alternative to self-owned and self-financed outpatient facilities and medical office buildings. The ownership and financing options available to physicians and physician groups considering the development of new medical projects have expanded greatly over the past few years and are likely to continue to evolve in the foreseeable future. This changing environment, driven by new sources of institutional capital and the emergence of qualified developers, has led to a more competitive market for physicians and groups seeking real estate capital partners, and physicians are starting to take advantage of it. Physicians and groups have embraced third-party ownership and management of real estate, because it can preserve capital resources and minimizes risk. These groups are using third parties to develop and own new medical real estate projects. This article describes medical real estate project development alternatives, the attributes and concerns of developers, typical transaction terms, and a recommended process for physicians and groups to select the best real estate development partner.

Different Visual Preference Patterns in Response to Simple and Complex Dynamic Social Stimuli in Preschool-Aged Children with Autism Spectrum Disorders

PubMed Central

Shi, Lijuan; Zhou, Yuanyue; Ou, Jianjun; Gong, Jingbo; Wang, Suhong; Cui, Xilong; Lyu, Hailong; Zhao, Jingping; Luo, Xuerong

2015-01-01

Eye-tracking studies in young children with autism spectrum disorder (ASD) have shown a visual attention preference for geometric patterns when viewing paired dynamic social images (DSIs) and dynamic geometric images (DGIs). In the present study, eye-tracking of two different paired presentations of DSIs and DGIs was monitored in a group of 13 children aged 4 to 6 years with ASD and 20 chronologically age-matched typically developing children (TDC). The results indicated that compared with the control group, children with ASD attended significantly less to DSIs showing two or more children playing than to similar DSIs showing a single child. Visual attention preference in 4- to 6-year-old children with ASDs, therefore, appears to be modulated by the type of visual stimuli. PMID:25781170

Relationship of tutors' group-dynamics skills to their performance ratings in problem-based learning.

PubMed

Dolmans, D H; Wolfhagen, I H; Scherpbier, A J; Vleuten, C P

2001-05-01

A tutor's performance is often investigated as a stable teacher characteristic, isolated from the context in which the tutor functions. This study investigated the influence of a tutor's group-dynamics skills in differently functioning tutorial groups on performance ratings. Students' ratings of tutors' performances collected from 75 tutorial groups at one school over four different academic years were compared with the independent variables, groups' cohesion scores and sponging scores (the degree to which some students let others do the work), and the intervening variable, tutors' group-dynamics skills. Tutors with strong group-dynamics skills were assigned mean tutor's-performance scores of 7.4 (SD = 0.8) and 8.2 (SD = 0.5), respectively, by groups scoring low and high on cohesion. Tutors with low group-dynamics skills were rated 7.0 (SD = 1.1) and 7.4 (SD = 1.1) by the same groups. The same pattern held for sponging scores. Tutors who had strong group-dynamics skills received mean tutor's-performance scores of 8.1 (SD = 0.6) and 7.4 (SD = 0.8), respectively, from groups with low and high sponging scores. Tutors with weak group-dynamics skills were scored 7.6 (SD = 1.0) and 6.9 (SD = 1.1) by the same groups. Tutors possessing group-dynamics skills were rated higher by students than were tutors who lacked these skills, irrespective of the quality of a tutorial group's performance. A tutor who evaluates tutorial-group function on a regular basis and makes appointments with students based on these evaluations is seen as performing better than a tutor who does not.

Frequency and phase synchronization in large groups: Low dimensional description of synchronized clapping, firefly flashing, and cricket chirping

NASA Astrophysics Data System (ADS)

Ott, Edward; Antonsen, Thomas M.

2017-05-01

A common observation is that large groups of oscillatory biological units often have the ability to synchronize. A paradigmatic model of such behavior is provided by the Kuramoto model, which achieves synchronization through coupling of the phase dynamics of individual oscillators, while each oscillator maintains a different constant inherent natural frequency. Here we consider the biologically likely possibility that the oscillatory units may be capable of enhancing their synchronization ability by adaptive frequency dynamics. We propose a simple augmentation of the Kuramoto model which does this. We also show that, by the use of a previously developed technique [Ott and Antonsen, Chaos 18, 037113 (2008)], it is possible to reduce the resulting dynamics to a lower dimensional system for the macroscopic evolution of the oscillator ensemble. By employing this reduction, we investigate the dynamics of our system, finding a characteristic hysteretic behavior and enhancement of the quality of the achieved synchronization.

Rasch model of a dynamic assessment: an investigation of the children's inferential thinking modifiability test.

PubMed

Rittner, Linda L; Pulos, Steven M

2014-01-01

The purpose of this study was to develop a general procedure for evaluation of a dynamic assessment and to demonstrate an analysis of a dynamic assessment, the CITM (Tzuriel, 1995b), as an objective measure for use as a group assessment. The techniques used to determine the fit of the CITM to a Rasch partial credit model are explicitly outlined. A modified format of the CITM was administered to 266 diverse second grade students in the USA; 58% of participants were identified as low SES. The participants (males n = 144) were White Anglo and Latino American students (55%), many of whom were first generation Mexican immigrants. The CITM was found to adequately fit a Rasch partial credit model (PCM) indicating that the CITM is a likely candidate for a group administered dynamic assessment that can be measured objectively. Data also supported that a model for objectively measuring change in learning ability for inferential thinking in the CITM was feasible.

FATE-HD: A spatially and temporally explicit integrated model for predicting vegetation structure and diversity at regional scale

PubMed Central

Isabelle, Boulangeat; Damien, Georges; Wilfried, Thuiller

2014-01-01

During the last decade, despite strenuous efforts to develop new models and compare different approaches, few conclusions have been drawn on their ability to provide robust biodiversity projections in an environmental change context. The recurring suggestions are that models should explicitly (i) include spatiotemporal dynamics; (ii) consider multiple species in interactions; and (iii) account for the processes shaping biodiversity distribution. This paper presents a biodiversity model (FATE-HD) that meets this challenge at regional scale by combining phenomenological and process-based approaches and using well-defined plant functional groups. FATE-HD has been tested and validated in a French National Park, demonstrating its ability to simulate vegetation dynamics, structure and diversity in response to disturbances and climate change. The analysis demonstrated the importance of considering biotic interactions, spatio-temporal dynamics, and disturbances in addition to abiotic drivers to simulate vegetation dynamics. The distribution of pioneer trees was particularly improved, as were all undergrowth functional groups. PMID:24214499

Dynamics of safety performance and culture: a group model building approach.

PubMed

Goh, Yang Miang; Love, Peter E D; Stagbouer, Greg; Annesley, Chris

2012-09-01

The management of occupational health and safety (OHS) including safety culture interventions is comprised of complex problems that are often hard to scope and define. Due to the dynamic nature and complexity of OHS management, the concept of system dynamics (SD) is used to analyze accident prevention. In this paper, a system dynamics group model building (GMB) approach is used to create a causal loop diagram of the underlying factors influencing the OHS performance of a major drilling and mining contractor in Australia. While the organization has invested considerable resources into OHS their disabling injury frequency rate (DIFR) has not been decreasing. With this in mind, rich individualistic knowledge about the dynamics influencing the DIFR was acquired from experienced employees with operations, health and safety and training background using a GMB workshop. Findings derived from the workshop were used to develop a series of causal loop diagrams that includes a wide range of dynamics that can assist in better understanding the causal influences OHS performance. The causal loop diagram provides a tool for organizations to hypothesize the dynamics influencing effectiveness of OHS management, particularly the impact on DIFR. In addition the paper demonstrates that the SD GMB approach has significant potential in understanding and improving OHS management. Copyright © 2011 Elsevier Ltd. All rights reserved.

Dynamic contact angle cycling homogenizes heterogeneous surfaces.

PubMed

Belibel, R; Barbaud, C; Mora, L

2016-12-01

In order to reduce restenosis, the necessity to develop the appropriate coating material of metallic stent is a challenge for biomedicine and scientific research over the past decade. Therefore, biodegradable copolymers of poly((R,S)-3,3 dimethylmalic acid) (PDMMLA) were prepared in order to develop a new coating exhibiting different custom groups in its side chain and being able to carry a drug. This material will be in direct contact with cells and blood. It consists of carboxylic acid and hexylic groups used for hydrophilic and hydrophobic character, respectively. The study of this material wettability and dynamic surface properties is of importance due to the influence of the chemistry and the potential motility of these chemical groups on cell adhesion and polymer kinetic hydrolysis. Cassie theory was used for the theoretical correction of contact angles of these chemical heterogeneous surfaces coatings. Dynamic Surface Analysis was used as practical homogenizer of chemical heterogeneous surfaces by cycling during many cycles in water. In this work, we confirmed that, unlike receding contact angle, advancing contact angle is influenced by the difference of only 10% of acidic groups (%A) in side-chain of polymers. It linearly decreases with increasing acidity percentage. Hysteresis (H) is also a sensitive parameter which is discussed in this paper. Finally, we conclude that cycling provides real information, thus avoiding theoretical Cassie correction. H(10)is the most sensible parameter to %A. Copyright © 2016 Elsevier B.V. All rights reserved.

Labor progress indices and dynamics of the individual uterine contraction during the active stage of labor.

PubMed

Ophir, Ella; Bornstein, Jacob; Odeh, Marwan; Kaminsky, Svetlana; Shnaider, Oleg; Megel, Yuri; Barnea, Ofer

2014-03-01

To obtain and study new data on the dynamics of the labor process and to develop a contraction-based index of labor progress. This study was carried out at the Delivery Room, Department of Obstetrics and Gynecology, Western Galilee Hospital, Nahariya, Israel, using a new device (Birth Track). We continuously monitored cervical dilatation (CD) and head descent (HD) in 30 nulliparaous women during active labor with (augmented group) and without (study group) oxytocin augmentation. This led to the development and validation of progress indices based on features extracted from continuous monitoring. There were no significant differences between the average of each parameter in the study and augmented groups, except for HD velocity. Average HD velocity was faster in the study group. Linear regression analyses demonstrated that head station (HS) amplitude and Toco amplitude were the best parameters for predicting HD velocity in both groups. In the study group, average HD velocity was also significantly related to Toco rate and contraction efficiency. In the augmented group, only a weak correlation with Toco rate was seen, and no correlation with contraction efficiency. With the assistance of the Birth Track device, we can obtain continuous data on the labor process and indices to estimate the labor progress process without the use of vaginal (manual) examination. © 2013 The Authors. Journal of Obstetrics and Gynaecology Research © 2013 Japan Society of Obstetrics and Gynecology.

The Fragility of Individual-Based Explanations of Social Hierarchies: A Test Using Animal Pecking Orders

PubMed Central

2016-01-01

The standard approach in accounting for hierarchical differentiation in biology and the social sciences considers a hierarchy as a static distribution of individuals possessing differing amounts of some valued commodity, assumes that the hierarchy is generated by micro-level processes involving individuals, and attempts to reverse engineer the processes that produced the hierarchy. However, sufficient experimental and analytical results are available to evaluate this standard approach in the case of animal dominance hierarchies (pecking orders). Our evaluation using evidence from hierarchy formation in small groups of both hens and cichlid fish reveals significant deficiencies in the three tenets of the standard approach in accounting for the organization of dominance hierarchies. In consequence, we suggest that a new approach is needed to explain the organization of pecking orders and, very possibly, by implication, for other kinds of social hierarchies. We develop an example of such an approach that considers dominance hierarchies to be dynamic networks, uses dynamic sequences of interaction (dynamic network motifs) to explain the organization of dominance hierarchies, and derives these dynamic sequences directly from observation of hierarchy formation. We test this dynamical explanation using computer simulation and find a good fit with actual dynamics of hierarchy formation in small groups of hens. We hypothesize that the same dynamic sequences are used in small groups of many other animal species forming pecking orders, and we discuss the data required to evaluate our hypothesis. Finally, we briefly consider how our dynamic approach may be generalized to other kinds of social hierarchies using the example of the distribution of empty gastropod (snail) shells occupied in populations of hermit crabs. PMID:27410230

Technical Evaluation Report on the Fluid Dynamics Panel Specialists’ Meeting on Effects of Adverse Weather on Aerodynamics (Les Effets des Conditions Meteorologiques Adverses sur l’Aerodynamique)

DTIC Science & Technology

1991-11-01

AD-A245 117 III~i~IIiiIiIIi~ifhII _________________________AGARD-R306 0 AGARD ADVISORY GROUP FOR AEROSPACE RESEARCH & DEVELOPMENT 4 7 RUE ANCELLE...REPRODUCE LEGIBLY. AGARD-AR-306 ADVISORY GROUP FOR AEROSPACE RESEARCH & DEVELOPMENT 7 RUE ANCELLE 92200 NEUILLY SUR SEINE FRANCE AGARD ADVISORY RIEPORT...Conditions NMeleorolovioiue,, Adverscs sur rAerodynarminiuc) - J.J. Reinrnann National ,\\cronautico and Space .\\drmintration L eip Research (Center

What an understanding of the dynamics of gossip has to teach about group dynamics and group leadership.

PubMed

Gans, Jerome S

2014-01-01

Although what transpires in group therapy is not gossip per se-except perhaps when absent or former members are discussed-listening to group interaction through an understanding of the dynamics of gossip can contribute to a greater appreciation of group dynamics and group leadership as well as enlarge therapeutic space. After examining the interpersonal dynamics of gossip, this paper discusses six ways in which an understanding of these dynamics can inform group leadership and shed light on group psychotherapy. Central features of gossip that appear in group interactions are explored: These include projection, displacement, self-esteem regulation, clarification of motivation, unself-consciousness, social comparison and bonding, avoidance of psychic pain, and making the ego-syntonic dystonic. The lively use of imagination in the mature phase of group therapy is conceived of as the time when the darker side of human nature-imagined gossip harnessed for therapeutic purposes-can be welcomed in and processed in a kind, playful, and compassionate manner.

Brief report: Representational momentum for dynamic facial expressions in pervasive developmental disorder.

PubMed

Uono, Shota; Sato, Wataru; Toichi, Motomi

2010-03-01

Individuals with pervasive developmental disorder (PDD) have difficulty with social communication via emotional facial expressions, but behavioral studies involving static images have reported inconsistent findings about emotion recognition. We investigated whether dynamic presentation of facial expression would enhance subjective perception of expressed emotion in 13 individuals with PDD and 13 typically developing controls. We presented dynamic and static emotional (fearful and happy) expressions. Participants were asked to match a changeable emotional face display with the last presented image. The results showed that both groups perceived the last image of dynamic facial expression to be more emotionally exaggerated than the static facial expression. This finding suggests that individuals with PDD have an intact perceptual mechanism for processing dynamic information in another individual's face.

Testing the Efficacy of OurSpace, a Brief, Group Dynamics-Based Physical Activity Intervention: A Randomized Controlled Trial.

PubMed

Irwin, Brandon; Kurz, Daniel; Chalin, Patrice; Thompson, Nicholas

2016-05-06

Emerging technologies (ie, mobile phones, Internet) may be effective tools for promoting physical activity (PA). However, few interventions have provided effective means to enhance social support through these platforms. Face-to-face programs that use group dynamics-based principles of behavior change have been shown to be highly effective in enhancing social support through promoting group cohesion and PA, but to date, no studies have examined their effects in Web-based programs. The aim was to explore proof of concept and test the efficacy of a brief, online group dynamics-based intervention on PA in a controlled experiment. We expected that the impact of the intervention on PA would be moderated by perceptions of cohesion and the partner's degree of presence in the online media. Participants (n=135) were randomized into same-sex dyads and randomly assigned to one of four experimental conditions: standard social support (standard), group dynamics-based-high presence, group dynamics-based-low presence, or individual control. Participants performed two sets of planking exercises (pre-post). Between sets, participants in partnered conditions interacted with a virtual partner using either a standard social support app or a group dynamics-based app (group dynamics-based-low presence and group dynamics-based-high presence), the latter of which they participated in a series of online team-building exercises. Individual participants were given an equivalent rest period between sets. To increase presence during the second set, participants in the group dynamics-based-high presence group saw a live video stream of their partner exercising. Perceptions of cohesion were measured using a modified PA Group Environment Questionnaire. Physical activity was calculated as the time persisted during set 2 after controlling for persistence in set 1. Perceptions of cohesion were higher in the group dynamics-based-low presence (overall mean 5.81, SD 1.04) condition compared to the standard (overall mean 5.04, SD 0.81) conditions ( P=.006), but did not differ between group dynamics-based-low presence and group dynamics-based-high presence (overall mean 5.42, SD 1.07) conditions ( P=.25). Physical activity was higher in the high presence condition (mean 64.48, SD 20.19, P=.01) than all other conditions (mean 53.3, SD 17.35). A brief, online group dynamics-based intervention may be an effective method of improving group cohesion in virtual PA groups. However, it may be insufficient on its own to improve PA.

Dynamic Torsional and Cyclic Fracture Behavior of ProFile Rotary Instruments at Continuous or Reciprocating Rotation as Visualized with High-speed Digital Video Imaging.

PubMed

Tokita, Daisuke; Ebihara, Arata; Miyara, Kana; Okiji, Takashi

2017-08-01

This study examined the dynamic fracture behavior of nickel-titanium rotary instruments in torsional or cyclic loading at continuous or reciprocating rotation by means of high-speed digital video imaging. The ProFile instruments (size 30, 0.06 taper; Dentsply Maillefer, Ballaigues, Switzerland) were categorized into 4 groups (n = 7 in each group) as follows: torsional/continuous (TC), torsional/reciprocating (TR), cyclic/continuous (CC), and cyclic/reciprocating (CR). Torsional loading was performed by rotating the instruments by holding the tip with a vise. For cyclic loading, a custom-made device with a 38° curvature was used. Dynamic fracture behavior was observed with a high-speed camera. The time to fracture was recorded, and the fractured surface was examined with scanning electron microscopy. The TC group initially exhibited necking of the file followed by the development of an initial crack line. The TR group demonstrated opening and closing of a crack according to its rotation in the cutting and noncutting directions, respectively. The CC group separated without any detectable signs of deformation. In the CR group, initial crack formation was recognized in 5 of 7 samples. The reciprocating rotation exhibited a longer time to fracture in both torsional and cyclic fatigue testing (P < .05). The scanning electron microscopic images showed a severely deformed surface in the TR group. The dynamic fracture behavior of NiTi rotary instruments, as visualized with high-speed digital video imaging, varied between the different modes of rotation and different fatigue testing. Reciprocating rotation induced a slower crack propagation and conferred higher fatigue resistance than continuous rotation in both torsional and cyclic loads. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Effect of progressive resistance exercise with neuromuscular joint facilitation on the dynamic balance performance of junior soccer players.

PubMed

Wang, Hongzhao; Huo, Ming; Guan, Peipei; Onoda, Ko; Chen, Di; Huang, Qiuchen; Maruyama, Hitoshi

2015-11-01

[Purpose] The aim of this study was to investigate the change in dynamic balance performance of junior soccer players after progressive resistance treatment with neuromuscular joint facilitation (NJF). [Subjects] The subjects were 14 healthy males who were divided into two groups, namely the NJF and control groups. The NJF group consisted of 8 subjects, and the control group consisted of 6 subjects. [Methods] The participants in the NJF group received NJF progressive resistance treatment. Dynamic balance performance was measured before and after 3 weeks of exercise. [Results] Significant improvement in dynamic balance performance was observed both in the NJF and control groups. In the NJF group, dynamic balance performance was significantly increased compared with that in the control group. [Conclusion] The NJF intervention shortened movement time, which implies that NJF is effective for dynamic balance performance.

The influence of workforce behavior on organizational performance.

PubMed

Cerdena, Ernesto A

2009-01-01

Individual attitudes, values, personalities, ethics, and cultural differences all have an influence in organizational behavior. The formation of a culturally harmonious organization leads to new levels of management and structure, transcending the distinct cultures of individual team members. Leaders must be able to improve group process by facilitating interaction among group members and by maximizing group dynamics, which can only develop when there is positive interdependence, accountability, constructive interaction, and social skills.

The dynamics of transmission and the dynamics of networks.

PubMed

Farine, Damien

2017-05-01

A toy example depicted here highlighting the results of a study in this issue of the Journal of Animal Ecology that investigates the impact of network dynamics on potential disease outbreaks. Infections (stars) that spread by contact only (left) reduce the predicted outbreak size compared to situations where individuals can become infected by moving through areas that previously contained infected individuals (right). This is potentially important in species where individuals, or in this case groups, have overlapping ranges (as depicted on the top right). Incorporating network dynamics that maintain information about the ordering of contacts (central blocks; including the ordering of spatial overlap as noted by the arrows that highlight the blue group arriving after the red group in top-right of the figure) is important for capturing how a disease might not have the opportunity to spread to all individuals. By contrast, a static or 'average' network (lower blocks) does not capture any of these dynamics. Interestingly, although static networks generally predict larger outbreak sizes, the authors find that in cases when transmission probability is low, this prediction can switch as a result of changes in the estimated intensity of contacts among individuals. [Colour figure can be viewed at wileyonlinelibrary.com]. Springer, A., Kappeler, P.M. & Nunn, C.L. (2017) Dynamic vs. static social networks in models of parasite transmission: Predicting Cryptosporidium spread in wild lemurs. Journal of Animal Ecology, 86, 419-433. The spread of disease or information through networks can be affected by several factors. Whether and how these factors are accounted for can fundamentally change the predicted impact of a spreading epidemic. Springer, Kappeler & Nunn () investigate the role of different modes of transmission and network dynamics on the predicted size of a disease outbreak across several groups of Verreaux's sifakas, a group-living species of lemur. While some factors, such as seasonality, led to consistent differences in the structure of social networks, using dynamic vs. static representations of networks generated differences in the predicted outbreak size of an emergent disease. These findings highlight some of the challenges associated with studying disease dynamics in animal populations, and the importance of continuing efforts to develop the network tools needed to study disease spread. © 2017 The Author. Journal of Animal Ecology © 2017 British Ecological Society.

Uncertainty Propagation Methods for High-Dimensional Complex Systems

NASA Astrophysics Data System (ADS)

Mukherjee, Arpan

Researchers are developing ever smaller aircraft called Micro Aerial Vehicles (MAVs). The Space Robotics Group has joined the field by developing a dragonfly-inspired MAV. This thesis presents two contributions to this project. The first is the development of a dynamical model of the internal MAV components to be used for tuning design parameters and as a future plant model. This model is derived using the Lagrangian method and differs from others because it accounts for the internal dynamics of the system. The second contribution of this thesis is an estimation algorithm that can be used to determine prototype performance and verify the dynamical model from the first part. Based on the Gauss-Newton Batch Estimator, this algorithm uses a single camera and known points of interest on the wing to estimate the wing kinematic angles. Unlike other single-camera methods, this method is probabilistically based rather than being geometric.

Chronic Effects of Different Rest Intervals Between Sets on Dynamic and Isometric Muscle Strength and Muscle Activity in Trained Older Women.

PubMed

Jambassi Filho, José Claudio; Gurjão, André Luiz Demantova; Ceccato, Marilia; Prado, Alexandre Konig Garcia; Gallo, Luiza Herminia; Gobbi, Sebastião

2017-09-01

This study investigated the chronic effects of different rest intervals (RIs) between sets on dynamic and isometric muscle strength and muscle activity. We used a repeated-measures design (pretraining and posttraining) with independent groups (different RI). Twenty-one resistance-trained older women (66.4 ± 4.4 years) were randomly assigned to either a 1-minute RI group (G-1 min; n = 10) or 3-minute RI group (G-3 min; n = 11). Both groups completed 3 supervised sessions per week during 8 weeks. In each session, participants performed 3 sets of 15 repetitions of leg press exercise, with a load that elicited muscle failure in the third set. Fifteen maximum repetitions, maximal voluntary contraction, peak rate of force development, and integrated electromyography activity of the vastus lateralis and vastus medialis muscles were assessed pretraining and posttraining. There was a significant increase in load of 15 maximum repetitions posttraining for G-3 min only (3.6%; P < 0.05). However, posttraining results showed no significant differences between G-1 min and G-3 min groups for all dependent variables (P > 0.05). The findings suggest that different RIs between sets did not influence dynamic and isometric muscle strength and muscle activity in resistance-trained older women.

Peer Culture Development: A School-Based Delinquency Prevention Program.

ERIC Educational Resources Information Center

Kottmann, William

This paper describes Peer Culture Development, Inc., a private, non-profit agency which provides a school-based delinquency prevention program to public schools. The basic components of the program are described along with the selection and role of student leaders in the program. The dynamics of the group meetings are discussed and seven…

Two Processes for Recognition Memory in Children of Early School Age: An Event-Related Potential Study

ERIC Educational Resources Information Center

Mecklinger, Axel; Brunnemann, Nicole; Kipp, Kerstin

2011-01-01

We examined the ERP correlates of familiarity and recollection and their development in 8- to 10-year-old children and a control group of young adults. Capitalizing on the different temporal dynamics of familiarity and recollection, we tested recognition memory in both groups with a speeded and nonspeeded response condition. Consistent with the…

A phenomenological research study: Perspectives of student learning through small group work between undergraduate nursing students and educators.

PubMed

Wong, Florence Mei Fung

2018-06-18

Small group work is an effective teaching-learning approach in nursing education to enhance students' learning in theoretical knowledge and skill development. Despite its potential advantageous effects on learning, little is known about its actual effects on students' learning from students' and educators' perspectives. To understand students' learning through small group work from the perspectives of students and educators. A qualitative study with focus group interviews was carried out. Semi-structured interviews with open-ended questions were performed with 13 undergraduate nursing students and 10 educators. Four main themes, "initiative learning", "empowerment of interactive group dynamics", "factors for creating effective learning environment", and "barriers influencing students' learning", were derived regarding students' learning in small group work based on the perspectives of the participants. The results showed the importance of learning attitudes of students in individual and group learning. Factors for creating an effective learning environment, including preference for forming groups, effective group size, and adequacy of discussion, facilitate students' learning with the enhancement of learning engagement in small group work. The identified barriers, such as "excessive group work", "conflicts", and "passive team members" can reduce students' motivation and enjoyment of learning. Small group work is recognized as an effective teaching method for knowledge enhancement and skill development in nursing education. All identified themes are important to understand the initiatives of students and group learning, factors influencing an effective learning environment, and barriers hindering students' learning. Nurse educators should pay more attention to the factors that influence an effective learning environment and reduce students' commitment and group dynamics. Moreover, students may need further support to reduce barriers that impede students' learning motivation and enjoyment. Copyright © 2018 Elsevier Ltd. All rights reserved.

Understanding the effects of time on collaborative learning processes in problem based learning: a mixed methods study.

PubMed

Hommes, J; Van den Bossche, P; de Grave, W; Bos, G; Schuwirth, L; Scherpbier, A

2014-10-01

Little is known how time influences collaborative learning groups in medical education. Therefore a thorough exploration of the development of learning processes over time was undertaken in an undergraduate PBL curriculum over 18 months. A mixed-methods triangulation design was used. First, the quantitative study measured how various learning processes developed within and over three periods in the first 1,5 study years of an undergraduate curriculum. Next, a qualitative study using semi-structured individual interviews focused on detailed development of group processes driving collaborative learning during one period in seven tutorial groups. The hierarchic multilevel analyses of the quantitative data showed that a varying combination of group processes developed within and over the three observed periods. The qualitative study illustrated development in psychological safety, interdependence, potency, group learning behaviour, social and task cohesion. Two new processes emerged: 'transactive memory' and 'convergence in mental models'. The results indicate that groups are dynamic social systems with numerous contextual influences. Future research should thus include time as an important influence on collaborative learning. Practical implications are discussed.

Using Focus Groups to Validate a Pharmacy Vaccination Training Program.

PubMed

Bushell, Mary; Morrissey, Hana; Ball, Patrick

2015-06-12

Introduction: Focus group methodology is commonly used to quickly collate, integrated views from a variety of different stakeholders. This paper provides an example of how focus groups can be employed to collate expert opinion informing amendments on a newly developed training program for integration into undergraduate pharmacy curricula. Materials and methods: Four focus groups were conducted, across three continents, to determine the appropriateness and reliability of a developed vaccination training program with nested injection skills training. All focus groups were comprised of legitimate experts in the field of vaccination, medicine and/or pharmacy. Results: Themes that emerged across focus groups informed amendments giving rise to a validated version of a training program. Discussion : The rigorous validation of the vaccination training program offers generalizable lessons to inform the design and validation of future training programs intended for the health sector and or pharmacy curricula. Using the knowledge and experience of focus group participants fostered collaborative problem solving and validation of material and concept development. The group dynamics of a focus group allowed synthesis of feedback in an inter-professional manner. Conclusions : This paper provides a demonstration of how focus groups can be structured and used by health researchers to validate a newly developed training program.

The influence of socio cultural dynamics on convergence communication of aquaculture agribusiness actors

NASA Astrophysics Data System (ADS)

Oktavia, Y.

2018-03-01

This research aims to: (1) Analyze the level of socio-cultural dynamics of agibusiness aquaculture actors. (2) Analyze the influence of socio-cultural dynamics on convergence communication of capacity development of aquaculture agribusiness actors.Data was collected by questionnaire and interview of group members on agribusiness. Data analyze was done by descriptive and inferential statistics with using SEM method. The result of descriptive statistics on 284 agribusiness members showed that: Socio-cultural dynamics of agibusiness aquaculture actors was in low category, as shown by lack of the role of customary institutions and quality of local leadership.The communication convergence is significantly and positively influenced by the communication behavior of agribusiness actors in access information.

A Computational Algorithm for Functional Clustering of Proteome Dynamics During Development

PubMed Central

Wang, Yaqun; Wang, Ningtao; Hao, Han; Guo, Yunqian; Zhen, Yan; Shi, Jisen; Wu, Rongling

2014-01-01

Phenotypic traits, such as seed development, are a consequence of complex biochemical interactions among genes, proteins and metabolites, but the underlying mechanisms that operate in a coordinated and sequential manner remain elusive. Here, we address this issue by developing a computational algorithm to monitor proteome changes during the course of trait development. The algorithm is built within the mixture-model framework in which each mixture component is modeled by a specific group of proteins that display a similar temporal pattern of expression in trait development. A nonparametric approach based on Legendre orthogonal polynomials was used to fit dynamic changes of protein expression, increasing the power and flexibility of protein clustering. By analyzing a dataset of proteomic dynamics during early embryogenesis of the Chinese fir, the algorithm has successfully identified several distinct types of proteins that coordinate with each other to determine seed development in this forest tree commercially and environmentally important to China. The algorithm will find its immediate applications for the characterization of mechanistic underpinnings for any other biological processes in which protein abundance plays a key role. PMID:24955031

Dynamic Group Formation Based on a Natural Phenomenon

ERIC Educational Resources Information Center

Zedadra, Amina; Lafifi, Yacine; Zedadra, Ouarda

2016-01-01

This paper presents a new approach of learners grouping in collaborative learning systems. This grouping process is based on traces left by learners. The goal is the circular dynamic grouping to achieve collaborative projects. The proposed approach consists of two main algorithms: (1) the circular grouping algorithm and (2) the dynamic grouping…

Effects of dynamical grouping on cooperation in N-person evolutionary snowdrift game

NASA Astrophysics Data System (ADS)

Ji, M.; Xu, C.; Hui, P. M.

2011-09-01

A population typically consists of agents that continually distribute themselves into different groups at different times. This dynamic grouping has recently been shown to be essential in explaining many features observed in human activities including social, economic, and military activities. We study the effects of dynamic grouping on the level of cooperation in a modified evolutionary N-person snowdrift game. Due to the formation of dynamical groups, the competition takes place in groups of different sizes at different times and players of different strategies are mixed by the grouping dynamics. It is found that the level of cooperation is greatly enhanced by the dynamic grouping of agents, when compared with a static population of the same size. As a parameter β, which characterizes the relative importance of the reward and cost, increases, the fraction of cooperative players fC increases and it is possible to achieve a fully cooperative state. Analytically, we present a dynamical equation that incorporates the effects of the competing game and group size distribution. The distribution of cooperators in different groups is assumed to be a binomial distribution, which is confirmed by simulations. Results from the analytic equation are in good agreement with numerical results from simulations. We also present detailed simulation results of fC over the parameter space spanned by the probabilities of group coalescence νm and group fragmentation νp in the grouping dynamics. A high νm and low νp promotes cooperation, and a favorable reward characterized by a high β would lead to a fully cooperative state.

Group personality during collective decision-making: a multi-level approach.

PubMed

Planas-Sitjà, Isaac; Deneubourg, Jean-Louis; Gibon, Céline; Sempo, Grégory

2015-03-07

Collective decision-making processes emerge from social feedback networks within a group. Many studies on collective behaviour underestimate the role of individual personality and, as a result, personality is rarely analysed in the context of collective dynamics. Here, we show evidence of sheltering behaviour personality in a gregarious insect (Periplaneta americana), which is characterized by a collective personality at the group level. We also highlight that the individuals within groups exhibited consistent personality traits in their probability of sheltering and total time sheltered during the three trials over one week. Moreover, the group personality, which arises from the synergy between the distribution of behaviour profiles in the group and social amplifications, affected the sheltering dynamics. However, owing to its robustness, personality did not affect the group probability of reaching a consensus. Finally, to prove social interactions, we developed a new statistical method that will be helpful for future research on personality traits and group behaviour. This approach will help to identify the circumstances under which particular group compositions may improve the fitness of individuals in gregarious species. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Quantitative characterisation of audio data by ordinal symbolic dynamics

NASA Astrophysics Data System (ADS)

Aschenbrenner, T.; Monetti, R.; Amigó, J. M.; Bunk, W.

2013-06-01

Ordinal symbolic dynamics has developed into a valuable method to describe complex systems. Recently, using the concept of transcripts, the coupling behaviour of systems was assessed, combining the properties of the symmetric group with information theoretic ideas. In this contribution, methods from the field of ordinal symbolic dynamics are applied to the characterisation of audio data. Coupling complexity between frequency bands of solo violin music, as a fingerprint of the instrument, is used for classification purposes within a support vector machine scheme. Our results suggest that coupling complexity is able to capture essential characteristics, sufficient to distinguish among different violins.

[Сhaotic dynamics of cardio-intervals in three age groups of indigenous and non-indigenous population of Ugra].

PubMed

Eskov, V M; Khadartsev, A A; Eskov, V V; Vokhmina, J V

2016-01-01

The problem of life expectancy of indigenous and non-indigenous population of northern territories of the Russian Federation is considered in terms of economic growth and industrial development of the northern territories. The importance of prolonging the period of active working age of non-indigenous population of Khanty-Mansi Autonomous Okrug-Ugra and Yamalo-Nenets Autonomous Okrug is increasing. Four directions for possible prolongation of the active life of non-indigenous population were presented. The problem of comparative dynamics of age-related changes of cardiovascular system on three specific age groups of female indigenous and non-indigenous population is being considered. A decrease in volume of quasi-attractors in the phase space of states is equivalent to strengthening of physical activity, which is typical of normal aging. It is proposed to use the mathematical pattern to reduce these volumes in assessing the dynamics of human aging in the North.

Computational Fluid Dynamics Assessment Associated with Transcatheter Heart Valve Prostheses: A Position Paper of the ISO Working Group.

PubMed

Wei, Zhenglun Alan; Sonntag, Simon Johannes; Toma, Milan; Singh-Gryzbon, Shelly; Sun, Wei

2018-04-19

The governing international standard for the development of prosthetic heart valves is International Organization for Standardization (ISO) 5840. This standard requires the assessment of the thrombus potential of transcatheter heart valve substitutes using an integrated thrombus evaluation. Besides experimental flow field assessment and ex vivo flow testing, computational fluid dynamics is a critical component of this integrated approach. This position paper is intended to provide and discuss best practices for the setup of a computational model, numerical solving, post-processing, data evaluation and reporting, as it relates to transcatheter heart valve substitutes. This paper is not intended to be a review of current computational technology; instead, it represents the position of the ISO working group consisting of experts from academia and industry with regards to considerations for computational fluid dynamic assessment of transcatheter heart valve substitutes.

Team Learning: New Insights Through a Temporal Lens.

PubMed

Lehmann-Willenbrock, Nale

2017-04-01

Team learning is a complex social phenomenon that develops and changes over time. Hence, to promote understanding of the fine-grained dynamics of team learning, research should account for the temporal patterns of team learning behavior. Taking important steps in this direction, this special issue offers novel insights into the dynamics of team learning by advocating a temporal perspective. Based on a symposium presented at the 2016 Interdisciplinary Network for Group Research (INGRoup) Conference in Helsinki, the four empirical articles in this special issue showcase four different and innovative approaches to implementing a temporal perspective in team learning research. Specifically, the contributions highlight team learning dynamics in student teams, self-managing teams, teacher teams, and command and control teams. The articles cover a broad range of methods and designs, including both qualitative and quantitative methodologies, and longitudinal as well as micro-temporal approaches. The contributors represent four countries and five different disciplines in group research.

A Systematic Approach for Determining Vertical Pile Depth of Embedment in Cohensionless Soils to Withstand Lateral Barge Train Impact Loads

DTIC Science & Technology

2017-01-30

dynamic structural time- history response analysis of flexible approach walls founded on clustered pile groups using Impact_Deck. In Preparation, ERDC...research (Ebeling et al. 2012) has developed simplified analysis procedures for flexible approach wall systems founded on clustered groups of vertical...history response analysis of flexible approach walls founded on clustered pile groups using Impact_Deck. In Preparation, ERDC/ITL TR-16-X. Vicksburg, MS

Jet and electromagnetic tomography (JET) of extreme phases of matter in heavy-ion collisions

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

Heinz, Ulrich

2015-08-31

The Ohio State University (OSU) group contributed to the deliverables of the JET Collaboration three major products: 1. The code package iEBE-VISHNU for modeling the dynamical evolution of the soft medium created in relativistic heavy-ion collisions, from its creation all the way to final freeze-out using a hybrid approach that interfaces a free-streaming partonic pre-equilbrium stage with a (2+1)-dimensional viscous relativistic fluid dynamical stage for the quark-gluon plasma (QGP) phase and the microscopic hadron cascade UrQMD for the hadronic rescattering and freeze-out stage. Except for UrQMD, all dynamical evolution components and interfaces were developed at OSU and tested and implementedmore » in collaboration with the Duke University group. 2. An electromagnetic radiation module for the calculation of thermal photon emission from the QGP and hadron resonance gas stages of a heavy-ion collision, with emission rates that have been corrected for viscous effects in the expanding medium consistent with the bulk evolution. The electromagnetic radiation module was developed under OSU leadership in collaboration with the McGill group and has been integrated in the iEBE-VISHNU code package. 3. An interface between the Monte Carlo jet shower evolution and hadronization codes developed by the Wayne State University (WSU), McGill and Texas A&M groups and the iEBE-VISHNU bulk evolution code, for performing jet quenching and jet shape modification studies in a realistically modeled evolving medium that was tuned to measured soft hadron data. Building on work performed at OSU for the theoretical framework used to describe the interaction of jets with the medium, initial work on the jet shower Monte Carlo was started at OSU and moved to WSU when OSU Visiting Assistant Professor Abhijit Majumder accepted a tenure track faculty position at WSU in September 2011. The jet-hydro interface was developed at OSU and WSU and tested and implemented in collaboration with the McGill, Texas A&M, and LBNL groups.« less

The dynamic relationship between plant architecture and competition

PubMed Central

Ford, E. David

2014-01-01

In this review, structural and functional changes are described in single-species, even-aged, stands undergoing competition for light. Theories of the competition process as interactions between whole plants have been advanced but have not been successful in explaining these changes and how they vary between species or growing conditions. This task now falls to researchers in plant architecture. Research in plant architecture has defined three important functions of individual plants that determine the process of canopy development and competition: (i) resource acquisition plasticity; (ii) morphogenetic plasticity; (iii) architectural variation in efficiency of interception and utilization of light. In this review, this research is synthesized into a theory for competition based on five groups of postulates about the functioning of plants in stands. Group 1: competition for light takes place at the level of component foliage and branches. Group 2: the outcome of competition is determined by the dynamic interaction between processes that exert dominance and processes that react to suppression. Group 3: species differences may affect both exertion of dominance and reaction to suppression. Group 4: individual plants may simultaneously exhibit, in different component parts, resource acquisition and morphogenetic plasticity. Group 5: mortality is a time-delayed response to suppression. Development of architectural models when combined with field investigations is identifying research needed to develop a theory of architectural influences on the competition process. These include analyses of the integration of foliage and branch components into whole-plant growth and precise definitions of environmental control of morphogenetic plasticity and its interaction with acquisition of carbon for plant growth. PMID:24987396

The dynamic relationship between plant architecture and competition.

PubMed

Ford, E David

2014-01-01

In this review, structural and functional changes are described in single-species, even-aged, stands undergoing competition for light. Theories of the competition process as interactions between whole plants have been advanced but have not been successful in explaining these changes and how they vary between species or growing conditions. This task now falls to researchers in plant architecture. Research in plant architecture has defined three important functions of individual plants that determine the process of canopy development and competition: (i) resource acquisition plasticity; (ii) morphogenetic plasticity; (iii) architectural variation in efficiency of interception and utilization of light. In this review, this research is synthesized into a theory for competition based on five groups of postulates about the functioning of plants in stands. Group 1: competition for light takes place at the level of component foliage and branches. Group 2: the outcome of competition is determined by the dynamic interaction between processes that exert dominance and processes that react to suppression. Group 3: species differences may affect both exertion of dominance and reaction to suppression. Group 4: individual plants may simultaneously exhibit, in different component parts, resource acquisition and morphogenetic plasticity. Group 5: mortality is a time-delayed response to suppression. Development of architectural models when combined with field investigations is identifying research needed to develop a theory of architectural influences on the competition process. These include analyses of the integration of foliage and branch components into whole-plant growth and precise definitions of environmental control of morphogenetic plasticity and its interaction with acquisition of carbon for plant growth.

Heterogeneous chain dynamics and aggregate lifetimes in precise acid-containing polyethylenes: Experiments and simulations

DOE PAGES

Middleton, L. Robert; Tarver, Jacob D.; Cordaro, Joseph; ...

2016-11-10

Melt state dynamics for a series of strictly linear polyethylenes with precisely spaced associating functional groups were investigated. The periodic pendant acrylic acid groups form hydrogen-bonded acid aggregates within the polyethylene (PE) matrix. The dynamics of these nanoscale heterogeneous morphologies were investigated from picosecond to nanosecond timescales by both quasi-elastic neutron scattering (QENS) measurements and fully atomistic molecular dynamics (MD) simulations. Two dynamic processes were observed. The faster dynamic processes which occur at the picosecond timescales are compositionally insensitive and indicative of spatially restricted local motions. The slower dynamic processes are highly composition dependent and indicate the structural relaxation ofmore » the polymer backbone. Higher acid contents, or shorter PE spacers between pendant acid groups, slow the structural relaxation timescale and increase the stretching parameter (β) of the structural relaxation. Additionally, the dynamics of specific hydrogen atom positions along the backbone correlate structural heterogeneity imposed by the associating acid groups with a mobility gradient along the polymer backbone. At time intervals (<2 ns), the mean-squared displacements for the four methylene groups closest to the acid groups are up to 10 times smaller than those of methylene groups further from the acid groups. At longer timescales acid aggregates rearrange and the chain dynamics of the slow, near-aggregate regions and the faster bridge regions converge, implying a characteristic timescale for the passage of chains between aggregates. As a result, the characterization of the nanoscale chain dynamics in these associating polymer systems both provides validation of simulation force fields and provides understanding of heterogeneous chain dynamics in associating polymers.« less

The Second International Piping Integrity Research Group (IPIRG-2) program. Final report, October 1991--April 1996

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

Hopper, A.; Wilowski, G.; Scott, P.

1997-03-01

The IPIRG-2 program was an international group program managed by the US NRC and funded by organizations from 15 nations. The emphasis of the IPIRG-2 program was the development of data to verify fracture analyses for cracked pipes and fittings subjected to dynamic/cyclic load histories typical of seismic events. The scope included: (1) the study of more complex dynamic/cyclic load histories, i.e., multi-frequency, variable amplitude, simulated seismic excitations, than those considered in the IPIRG-1 program, (2) crack sizes more typical of those considered in Leak-Before-Break (LBB) and in-service flaw evaluations, (3) through-wall-cracked pipe experiments which can be used to validatemore » LBB-type fracture analyses, (4) cracks in and around pipe fittings, such as elbows, and (5) laboratory specimen and separate effect pipe experiments to provide better insight into the effects of dynamic and cyclic load histories. Also undertaken were an uncertainty analysis to identify the issues most important for LBB or in-service flaw evaluations, updating computer codes and databases, the development and conduct of a series of round-robin analyses, and analyst`s group meetings to provide a forum for nuclear piping experts from around the world to exchange information on the subject of pipe fracture technology. 17 refs., 104 figs., 41 tabs.« less

Cognitive synergy in groups and group-to-individual transfer of decision-making competencies

PubMed Central

Curşeu, Petru L.; Meslec, Nicoleta; Pluut, Helen; Lucas, Gerardus J. M.

2015-01-01

In a field study (148 participants organized in 38 groups) we tested the effect of group synergy and one's position in relation to the collaborative zone of proximal development (CZPD) on the change of individual decision-making competencies. We used two parallel sets of decision tasks reported in previous research to test rationality and we evaluated individual decision-making competencies in the pre-group and post-group conditions as well as group rationality (as an emergent group level phenomenon). We used multilevel modeling to analyze the data and the results showed that members of synergetic groups had a higher cognitive gain as compared to members of non-synergetic groups, while highly rational members (members above the CZPD) had lower cognitive gains compared to less rational group members (members situated below the CZPD). These insights extend the literature on group-to-individual transfer of learning and have important practical implications as they show that group dynamics influence the development of individual decision-making competencies. PMID:26441750

Cognitive synergy in groups and group-to-individual transfer of decision-making competencies.

PubMed

Curşeu, Petru L; Meslec, Nicoleta; Pluut, Helen; Lucas, Gerardus J M

2015-01-01

In a field study (148 participants organized in 38 groups) we tested the effect of group synergy and one's position in relation to the collaborative zone of proximal development (CZPD) on the change of individual decision-making competencies. We used two parallel sets of decision tasks reported in previous research to test rationality and we evaluated individual decision-making competencies in the pre-group and post-group conditions as well as group rationality (as an emergent group level phenomenon). We used multilevel modeling to analyze the data and the results showed that members of synergetic groups had a higher cognitive gain as compared to members of non-synergetic groups, while highly rational members (members above the CZPD) had lower cognitive gains compared to less rational group members (members situated below the CZPD). These insights extend the literature on group-to-individual transfer of learning and have important practical implications as they show that group dynamics influence the development of individual decision-making competencies.

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

NASA Astrophysics Data System (ADS)

George, Mishel; Bullo, Francesco; Campàs, Otger

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

Collective motion of macroscopic spheres floating on capillary ripples: Dynamic heterogeneity and dynamic criticality

NASA Astrophysics Data System (ADS)

Sanlı, Ceyda; Saitoh, Kuniyasu; Luding, Stefan; van der Meer, Devaraj

2014-09-01

When a densely packed monolayer of macroscopic spheres floats on chaotic capillary Faraday waves, a coexistence of large scale convective motion and caging dynamics typical for glassy systems is observed. We subtract the convective mean flow using a coarse graining (homogenization) method and reveal subdiffusion for the caging time scales followed by a diffusive regime at later times. We apply the methods developed to study dynamic heterogeneity and show that the typical time and length scales of the fluctuations due to rearrangements of observed particle groups significantly increase when the system approaches its largest experimentally accessible packing concentration. To connect the system to the dynamic criticality literature, we fit power laws to our results. The resultant critical exponents are consistent with those found in densely packed suspensions of colloids.

Collective motion of macroscopic spheres floating on capillary ripples: dynamic heterogeneity and dynamic criticality.

PubMed

Sanlı, Ceyda; Saitoh, Kuniyasu; Luding, Stefan; van der Meer, Devaraj

2014-09-01

When a densely packed monolayer of macroscopic spheres floats on chaotic capillary Faraday waves, a coexistence of large scale convective motion and caging dynamics typical for glassy systems is observed. We subtract the convective mean flow using a coarse graining (homogenization) method and reveal subdiffusion for the caging time scales followed by a diffusive regime at later times. We apply the methods developed to study dynamic heterogeneity and show that the typical time and length scales of the fluctuations due to rearrangements of observed particle groups significantly increase when the system approaches its largest experimentally accessible packing concentration. To connect the system to the dynamic criticality literature, we fit power laws to our results. The resultant critical exponents are consistent with those found in densely packed suspensions of colloids.

How Ebola impacts social dynamics in gorillas: a multistate modelling approach.

PubMed

Genton, Céline; Pierre, Amandine; Cristescu, Romane; Lévréro, Florence; Gatti, Sylvain; Pierre, Jean-Sébastien; Ménard, Nelly; Le Gouar, Pascaline

2015-01-01

Emerging infectious diseases can induce rapid changes in population dynamics and threaten population persistence. In socially structured populations, the transfers of individuals between social units, for example, from breeding groups to non-breeding groups, shape population dynamics. We suggest that diseases may affect these crucial transfers. We aimed to determine how disturbance by an emerging disease affects demographic rates of gorillas, especially transfer rates within populations and immigration rates into populations. We compared social dynamics and key demographic parameters in a gorilla population affected by Ebola using a long-term observation data set including pre-, during and post-outbreak periods. We also studied a population of undetermined epidemiological status in order to assess whether this population was affected by the disease. We developed a multistate model that can handle transition between social units while optimizing the number of states. During the Ebola outbreak, social dynamics displayed increased transfers from a breeding to a non-breeding status for both males and females. Six years after the outbreak, demographic and most of social dynamics parameters had returned to their initial rates, suggesting a certain resilience in the response to disruption. The formation of breeding groups increased just after Ebola, indicating that environmental conditions were still attractive. However, population recovery was likely delayed because compensatory immigration was probably impeded by the potential impact of Ebola in the surrounding areas. The population of undetermined epidemiological status behaved similarly to the other population before Ebola. Our results highlight the need to integrate social dynamics in host-population demographic models to better understand the role of social structure in the sensitivity and the response to disease disturbances. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

Effective Group Dynamics: Theories and Practices.

ERIC Educational Resources Information Center

Murk, Peter J.

Using a brief experiential group activity called "Choosing a Color Exercise" as an introductory measure, this paper explains the basics of group dynamics and reviews the major theoretical relationships between the group's structure, the dynamics of maintenance and task behaviors, and effective individual performances. The types of functional and…

Managing parental groups: personal impact of a group leadership course for child healthcare nurses.

PubMed

Lefèvre, Åsa; Lundqvist, Pia; Drevenhorn, Eva; Hallström, Inger

2017-02-01

To investigate the experience and personal impact of a group leadership course for child healthcare nurses. During their child's first year, all parents in Sweden are invited to participate in parental groups within the child health service; however, only 49% choose to participate. Despite extensive experience, child healthcare nurses find managing parental groups challenging and express a need for training in group dynamics and group leadership. The study was designed as a controlled study with a pretest/post-test design where the participants form their own control group. A group leadership course was given to 56 child healthcare nurses and evaluated in a pre- and postintervention questionnaire, a course evaluation and an interview with the course leaders. The child healthcare nurses felt their group leadership skills were strengthened and the majority (96%) felt that the course had changed their way of leading parental groups. They felt that the group leader role had been clarified and that they had obtained several new tools to use in their groups. Clarifying the role of group leader and adding knowledge about group leadership and dynamics seems to have increased the self-confidence for child healthcare nurses in group leadership. Improved confidence in group management might motivate the child healthcare nurses to further develop parental groups to attract the parents who currently choose not to participate. © 2016 John Wiley & Sons Ltd.

Hydrogen bond dynamics in bulk alcohols.

PubMed

Shinokita, Keisuke; Cunha, Ana V; Jansen, Thomas L C; Pshenichnikov, Maxim S

2015-06-07

Hydrogen-bonded liquids play a significant role in numerous chemical and biological phenomena. In the past decade, impressive developments in multidimensional vibrational spectroscopy and combined molecular dynamics-quantum mechanical simulation have established many intriguing features of hydrogen bond dynamics in one of the fundamental solvents in nature, water. The next class of a hydrogen-bonded liquid--alcohols--has attracted much less attention. This is surprising given such important differences between water and alcohols as the imbalance between the number of hydrogen bonds, each molecule can accept (two) and donate (one) and the very presence of the hydrophobic group in alcohols. Here, we use polarization-resolved pump-probe and 2D infrared spectroscopy supported by extensive theoretical modeling to investigate hydrogen bond dynamics in methanol, ethanol, and isopropanol employing the OH stretching mode as a reporter. The sub-ps dynamics in alcohols are similar to those in water as they are determined by similar librational and hydrogen-bond stretch motions. However, lower density of hydrogen bond acceptors and donors in alcohols leads to the appearance of slow diffusion-controlled hydrogen bond exchange dynamics, which are essentially absent in water. We anticipate that the findings herein would have a potential impact on fundamental chemistry and biology as many processes in nature involve the interplay of hydrophobic and hydrophilic groups.

Dynamic route and departure time choice model based on self-adaptive reference point and reinforcement learning

NASA Astrophysics Data System (ADS)

Li, Xue-yan; Li, Xue-mei; Yang, Lingrun; Li, Jing

2018-07-01

Most of the previous studies on dynamic traffic assignment are based on traditional analytical framework, for instance, the idea of Dynamic User Equilibrium has been widely used in depicting both the route choice and the departure time choice. However, some recent studies have demonstrated that the dynamic traffic flow assignment largely depends on travelers' rationality degree, travelers' heterogeneity and what the traffic information the travelers have. In this paper, we develop a new self-adaptive multi agent model to depict travelers' behavior in Dynamic Traffic Assignment. We use Cumulative Prospect Theory with heterogeneous reference points to illustrate travelers' bounded rationality. We use reinforcement-learning model to depict travelers' route and departure time choosing behavior under the condition of imperfect information. We design the evolution rule of travelers' expected arrival time and the algorithm of traffic flow assignment. Compared with the traditional model, the self-adaptive multi agent model we proposed in this paper can effectively help travelers avoid the rush hour. Finally, we report and analyze the effect of travelers' group behavior on the transportation system, and give some insights into the relation between travelers' group behavior and the performance of transportation system.

Dynamics of Alliance Formation and the Egalitarian Revolution

PubMed Central

Gavrilets, Sergey; Duenez-Guzman, Edgar A.; Vose, Michael D.

2008-01-01

Background Arguably the most influential force in human history is the formation of social coalitions and alliances (i.e., long-lasting coalitions) and their impact on individual power. Understanding the dynamics of alliance formation and its consequences for biological, social, and cultural evolution is a formidable theoretical challenge. In most great ape species, coalitions occur at individual and group levels and among both kin and non-kin. Nonetheless, ape societies remain essentially hierarchical, and coalitions rarely weaken social inequality. In contrast, human hunter-gatherers show a remarkable tendency to egalitarianism, and human coalitions and alliances occur not only among individuals and groups, but also among groups of groups. These observations suggest that the evolutionary dynamics of human coalitions can only be understood in the context of social networks and cognitive evolution. Methodology/Principal Findings Here, we develop a stochastic model describing the emergence of networks of allies resulting from within-group competition for status or mates between individuals utilizing dyadic information. The model shows that alliances often emerge in a phase transition-like fashion if the group size, awareness, aggressiveness, and persuasiveness of individuals are large and the decay rate of individual affinities is small. With cultural inheritance of social networks, a single leveling alliance including all group members can emerge in several generations. Conclusions/Significance We propose a simple and flexible theoretical approach for studying the dynamics of alliance emergence applicable where game-theoretic methods are not practical. Our approach is both scalable and expandable. It is scalable in that it can be generalized to larger groups, or groups of groups. It is expandable in that it allows for inclusion of additional factors such as behavioral, genetic, social, and cultural features. Our results suggest that a rapid transition from a hierarchical society of great apes to an egalitarian society of hunter-gatherers (often referred to as “egalitarian revolution”) could indeed follow an increase in human cognitive abilities. The establishment of stable group-wide egalitarian alliances creates conditions promoting the origin of cultural norms favoring the group interests over those of individuals. PMID:18827928

A Strategic Defense Initiative Organization Software Testing Initiative

DTIC Science & Technology

1990-10-01

One group of researchers is investigating a version of this analysis termed constrained expression analysis [Dillon 1988c]. Here a design is...examined. Academic researchers will assist in developing experiments. In addition, an organization or group of people will be identified 14 as the focal...to make the transition into common practice. Research is being conducted into control -based test data adequacy criteria to support the dynamic

Using a Dual Role Assignment to Improve Group Dynamics and Performance: The Effects of Facilitating Social Capital in Teams

ERIC Educational Resources Information Center

Aquino, Karl; Serva, Mark A.

2005-01-01

This article describes a project that simulates the interplay between management and development project teams in a business environment. Each student team was assigned a management role supervising one project and a development role implementing another project. Results indicate that teams that communicate regularly and interact socially outside…

Functional groups show distinct differences in nitrogen cycling during early stand development: implications for forest management

Treesearch

Doug P. Aubrey; David R. Coyle; Mark D. Coleman

2012-01-01

Background and aims Nutrient acquisition of forest stands is controlled by soil resource availability and belowground production, but tree species are rarely compared in this regard. Here, we examine ecological and management implications of nitrogen (N) dynamics during early forest stand development in productive commercial tree species with narrow (Populus...

The critical loads and levels approach for nitrogen

Treesearch

T.A. Clair; T. Blett; J. Aherne; M.P.M. Aidar; R. Artz; W.J. Bealey; W. Budd; J.N. Cape; C.J. Curtis; L. Duan; M.E. Fenn; P. Groffman; R. Haeuber; J.R. Hall; J.-P. Hettelingh; D. López-Hernández; B. Mathieson; L. Pardo; M. Posch; R.V. Pouyat; T. Spranger; H. Sverdrup; H. van Dobben; A. van Hinsberg

2014-01-01

This chapter reports the findings of a Working Group to review the critical loads (CLs) and levels approach for nitrogen (N). The three main approaches to estimating CLs are empirical, mass balance and dynamic modelling. Examples are given of recent developments in Europe, North America and Asia and it is concluded that other countries should be encouraged to develop...

A Life-Cycle Model of Human Social Groups Produces a U-Shaped Distribution in Group Size.

PubMed

Salali, Gul Deniz; Whitehouse, Harvey; Hochberg, Michael E

2015-01-01

One of the central puzzles in the study of sociocultural evolution is how and why transitions from small-scale human groups to large-scale, hierarchically more complex ones occurred. Here we develop a spatially explicit agent-based model as a first step towards understanding the ecological dynamics of small and large-scale human groups. By analogy with the interactions between single-celled and multicellular organisms, we build a theory of group lifecycles as an emergent property of single cell demographic and expansion behaviours. We find that once the transition from small-scale to large-scale groups occurs, a few large-scale groups continue expanding while small-scale groups gradually become scarcer, and large-scale groups become larger in size and fewer in number over time. Demographic and expansion behaviours of groups are largely influenced by the distribution and availability of resources. Our results conform to a pattern of human political change in which religions and nation states come to be represented by a few large units and many smaller ones. Future enhancements of the model should include decision-making rules and probabilities of fragmentation for large-scale societies. We suggest that the synthesis of population ecology and social evolution will generate increasingly plausible models of human group dynamics.

A Life-Cycle Model of Human Social Groups Produces a U-Shaped Distribution in Group Size

PubMed Central

Salali, Gul Deniz; Whitehouse, Harvey; Hochberg, Michael E.

2015-01-01

One of the central puzzles in the study of sociocultural evolution is how and why transitions from small-scale human groups to large-scale, hierarchically more complex ones occurred. Here we develop a spatially explicit agent-based model as a first step towards understanding the ecological dynamics of small and large-scale human groups. By analogy with the interactions between single-celled and multicellular organisms, we build a theory of group lifecycles as an emergent property of single cell demographic and expansion behaviours. We find that once the transition from small-scale to large-scale groups occurs, a few large-scale groups continue expanding while small-scale groups gradually become scarcer, and large-scale groups become larger in size and fewer in number over time. Demographic and expansion behaviours of groups are largely influenced by the distribution and availability of resources. Our results conform to a pattern of human political change in which religions and nation states come to be represented by a few large units and many smaller ones. Future enhancements of the model should include decision-making rules and probabilities of fragmentation for large-scale societies. We suggest that the synthesis of population ecology and social evolution will generate increasingly plausible models of human group dynamics. PMID:26381745

Global Genetic Response in a Cancer Cell: Self-Organized Coherent Expression Dynamics

PubMed Central

Tsuchiya, Masa; Hashimoto, Midori; Takenaka, Yoshiko; Motoike, Ikuko N.; Yoshikawa, Kenichi

2014-01-01

Understanding the basic mechanism of the spatio-temporal self-control of genome-wide gene expression engaged with the complex epigenetic molecular assembly is one of major challenges in current biological science. In this study, the genome-wide dynamical profile of gene expression was analyzed for MCF-7 breast cancer cells induced by two distinct ErbB receptor ligands: epidermal growth factor (EGF) and heregulin (HRG), which drive cell proliferation and differentiation, respectively. We focused our attention to elucidate how global genetic responses emerge and to decipher what is an underlying principle for dynamic self-control of genome-wide gene expression. The whole mRNA expression was classified into about a hundred groups according to the root mean square fluctuation (rmsf). These expression groups showed characteristic time-dependent correlations, indicating the existence of collective behaviors on the ensemble of genes with respect to mRNA expression and also to temporal changes in expression. All-or-none responses were observed for HRG and EGF (biphasic statistics) at around 10–20 min. The emergence of time-dependent collective behaviors of expression occurred through bifurcation of a coherent expression state (CES). In the ensemble of mRNA expression, the self-organized CESs reveals distinct characteristic expression domains for biphasic statistics, which exhibits notably the presence of criticality in the expression profile as a route for genomic transition. In time-dependent changes in the expression domains, the dynamics of CES reveals that the temporal development of the characteristic domains is characterized as autonomous bistable switch, which exhibits dynamic criticality (the temporal development of criticality) in the genome-wide coherent expression dynamics. It is expected that elucidation of the biophysical origin for such critical behavior sheds light on the underlying mechanism of the control of whole genome. PMID:24831017

Group-size-mediated habitat selection and group fusion-fission dynamics of bison under predation risk.

PubMed

Fortin, Daniel; Fortin, Marie-Eve; Beyer, Hawthorne L; Duchesne, Thierry; Courant, Sabrina; Dancose, Karine

2009-09-01

For gregarious animals the cost-benefit trade-offs that drive habitat selection may vary dynamically with group size, which plays an important role in foraging and predator avoidance strategies. We examined how habitat selection by bison (Bison bison) varied as a function of group size and interpreted these patterns by testing whether habitat selection was more strongly driven by the competing demands of forage intake vs. predator avoidance behavior. We developed an analytical framework that integrated group size into resource selection functions (RSFs). These group-size-dependent RSFs were based on a matched case-control design and were estimated using conditional logistic regression (mixed and population-averaged models). Fitting RSF models to bison revealed that bison groups responded to multiple aspects of landscape heterogeneity and that selection varied seasonally and as a function of group size. For example, roads were selected in summer, but not in winter. Bison groups avoided areas of high snow water equivalent in winter. They selected areas composed of a large proportion of meadow area within a 700-m radius, and within those areas, bison selected meadows. Importantly, the strength of selection for meadows varied as a function of group size, with stronger selection being observed in larger groups. Hence the bison-habitat relationship depended in part on the dynamics of group formation and division. Group formation was most likely in meadows. In contrast, risk of group fission increased when bison moved into the forest and was higher during the time of day when movements are generally longer and more variable among individuals. We also found that stronger selection for meadows by large rather than small bison groups was caused by longer residence time in individual meadows by larger groups and that departure from meadows appears unlikely to result from a depression in food intake rate. These group-size-dependent patterns were consistent with the hypothesis that avoidance of predation risk is the strongest driver of habitat selection.

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

Middleton, L. Robert; Tarver, Jacob D.; Cordaro, Joseph

Melt state dynamics for a series of strictly linear polyethylenes with precisely spaced associating functional groups were investigated. The periodic pendant acrylic acid groups form hydrogen-bonded acid aggregates within the polyethylene (PE) matrix. The dynamics of these nanoscale heterogeneous morphologies were investigated from picosecond to nanosecond timescales by both quasi-elastic neutron scattering (QENS) measurements and fully atomistic molecular dynamics (MD) simulations. Two dynamic processes were observed. The faster dynamic processes which occur at the picosecond timescales are compositionally insensitive and indicative of spatially restricted local motions. The slower dynamic processes are highly composition dependent and indicate the structural relaxation ofmore » the polymer backbone. Higher acid contents, or shorter PE spacers between pendant acid groups, slow the structural relaxation timescale and increase the stretching parameter (β) of the structural relaxation. Additionally, the dynamics of specific hydrogen atom positions along the backbone correlate structural heterogeneity imposed by the associating acid groups with a mobility gradient along the polymer backbone. At time intervals (<2 ns), the mean-squared displacements for the four methylene groups closest to the acid groups are up to 10 times smaller than those of methylene groups further from the acid groups. At longer timescales acid aggregates rearrange and the chain dynamics of the slow, near-aggregate regions and the faster bridge regions converge, implying a characteristic timescale for the passage of chains between aggregates. As a result, the characterization of the nanoscale chain dynamics in these associating polymer systems both provides validation of simulation force fields and provides understanding of heterogeneous chain dynamics in associating polymers.« less

A Simplified Approach to Risk Assessment Based on System Dynamics: An Industrial Case Study.

PubMed

Garbolino, Emmanuel; Chery, Jean-Pierre; Guarnieri, Franck

2016-01-01

Seveso plants are complex sociotechnical systems, which makes it appropriate to support any risk assessment with a model of the system. However, more often than not, this step is only partially addressed, simplified, or avoided in safety reports. At the same time, investigations have shown that the complexity of industrial systems is frequently a factor in accidents, due to interactions between their technical, human, and organizational dimensions. In order to handle both this complexity and changes in the system over time, this article proposes an original and simplified qualitative risk evaluation method based on the system dynamics theory developed by Forrester in the early 1960s. The methodology supports the development of a dynamic risk assessment framework dedicated to industrial activities. It consists of 10 complementary steps grouped into two main activities: system dynamics modeling of the sociotechnical system and risk analysis. This system dynamics risk analysis is applied to a case study of a chemical plant and provides a way to assess the technological and organizational components of safety. © 2016 Society for Risk Analysis.

Have adults lost their sense of play? An observational study of the social dynamics of physical (in)activity in German and Hawaiian leisure settings.

PubMed

Thiel, Ansgar; Thedinga, Hendrik K; Thomas, Samantha L; Barkhoff, Harald; Giel, Katrin E; Schweizer, Olesia; Thiel, Syra; Zipfel, Stephan

2016-08-02

Physical inactivity is one of the biggest health problems nowadays. Recent research shows that socio-cultural barriers to physical activity are mostly related to modern lifestyles. However, there is a lack of research on how social and group dynamics influence engagement in physical activity. Furthermore, there are few cross-cultural studies that have compared the social dynamics of (in)activity in different cultural settings. This paper therefore aims to analyse how social group dynamics influence physical activity and inactivity in informal social environments and whether physical activity is influenced by the socio-cultural settings. The paper presents the qualitative data collected within a covert participant observation study. Data was collected by keeping observational notes in order to record typical, regular patterns regarding physical (in)activity related behaviour of groups at an artificial open air swimming pool in Germany and a natural pond in Hawai'i. The data collection period was eight and a half months. Data was interpreted based on constant comparative analysis in order to identify most generative patterns in the field notes. Group structures appear to play a significant role regarding the activity of the group members. In this study, we identified four key factors that influence group based physical activity: 1) Physical activity seems to be a group disturbing behaviour particularly in larger groups of adults; 2) Physical activity appears to be more functional and less joyful in adults than in children; 3) Group activity is influenced by (in)activity anchors, including 'domestication' of a group's site, obesity, and controlling parents. 4) Physical activity is to a certain extent socially contagious, particularly with regard to playful activities. Successful promotion of physical activity should target the social structures of inactive individuals' groups. In this regard, one of the main problems is that fun and wellbeing, as very important targets of public health strategies for the adult population, appear not to be compatible with physical activity. Developing strategies to reframe physical activity rather as 'fun' and less as functional may be one way to engage inactive individuals in physical activity in leisure settings.

Brain Dynamics: Methodological Issues and Applications in Psychiatric and Neurologic Diseases

NASA Astrophysics Data System (ADS)

Pezard, Laurent

The human brain is a complex dynamical system generating the EEG signal. Numerical methods developed to study complex physical dynamics have been used to characterize EEG since the mid-eighties. This endeavor raised several issues related to the specificity of EEG. Firstly, theoretical and methodological studies should address the major differences between the dynamics of the human brain and physical systems. Secondly, this approach of EEG signal should prove to be relevant for dealing with physiological or clinical problems. A set of studies performed in our group is presented here within the context of these two problematic aspects. After the discussion of methodological drawbacks, we review numerical simulations related to the high dimension and spatial extension of brain dynamics. Experimental studies in neurologic and psychiatric disease are then presented. We conclude that if it is now clear that brain dynamics changes in relation with clinical situations, methodological problems remain largely unsolved.

CELSS science needs

NASA Technical Reports Server (NTRS)

Rummel, J. D.

1986-01-01

Questions and areas of study that need to be persued in order to develope a Controlled Ecological Life Support System are posed. Research topics needing attention are grouped under various leadings: ecology, genetics, plant pathology, cybernetics, chemistry, computer science, fluid dynamics, optics, and solid-state physics.

Developing and Validating a Synthetic Teammate

DTIC Science & Technology

2010-01-31

reveals the stability of team coordination dynamics, the Hurst exponent , was also analyzed to determine if there was a coordination stability...difference between communication groups. An independent samples Mest on the average Hurst exponents across teams revealed that text-comm teams were, on

Binocular rivalry in children on the autism spectrum

PubMed Central

Lunghi, Claudia; Neil, Louise; Burr, David; Pellicano, Elizabeth

2017-01-01

When different images are presented to the eyes, the brain is faced with ambiguity, causing perceptual bistability: visual perception continuously alternates between the monocular images, a phenomenon called binocular rivalry. Many models of rivalry suggest that its temporal dynamics depend on mutual inhibition among neurons representing competing images. These models predict that rivalry should be different in autism, which has been proposed to present an atypical ratio of excitation and inhibition [the E/I imbalance hypothesis; Rubenstein & Merzenich, 2003]. In line with this prediction, some recent studies have provided evidence for atypical binocular rivalry dynamics in autistic adults. In this study, we examined if these findings generalize to autistic children. We developed a child‐friendly binocular rivalry paradigm, which included two types of stimuli, low‐ and high‐complexity, and compared rivalry dynamics in groups of autistic and age‐ and intellectual ability‐matched typical children. Unexpectedly, the two groups of children presented the same number of perceptual transitions and the same mean phase durations (times perceiving one of the two stimuli). Yet autistic children reported mixed percepts for a shorter proportion of time (a difference which was in the opposite direction to previous adult studies), while elevated autistic symptomatology was associated with shorter mixed perception periods. Rivalry in the two groups was affected similarly by stimulus type, and consistent with previous findings. Our results suggest that rivalry dynamics are differentially affected in adults and developing autistic children and could be accounted for by hierarchical models of binocular rivalry, including both inhibition and top‐down influences. Autism Res 2017. ©2017 The Authors Autism Research published by Wiley Periodicals, Inc. on behalf of International Society for Autism Research Autism Res 2017, 10: 1096–1106. © 2017 International Society for Autism Research, Wiley Periodicals, Inc. PMID:28301094

Density dependence in group dynamics of a highly social mongoose, Suricata suricatta.

PubMed

Bateman, Andrew W; Ozgul, Arpat; Coulson, Tim; Clutton-Brock, Tim H

2012-05-01

1. For social species, the link between individual behaviour and population dynamics is mediated by group-level demography. 2. Populations of obligate cooperative breeders are structured into social groups, which may be subject to inverse density dependence (Allee effects) that result from a dependence on conspecific helpers, but evidence for population-wide Allee effects is rare. 3. We use field data from a long-term study of cooperative meerkats (Suricata suricatta; Schreber, 1776) - a species for which local Allee effects are not reflected in population-level dynamics - to empirically model interannual group dynamics. 4. Using phenomenological population models, modified to incorporate environmental conditions and potential Allee effects, we first investigate overall patterns of group dynamics and find support only for conventional density dependence that increases after years of low rainfall. 5. To explain the observed patterns, we examine specific demographic rates and assess their contributions to overall group dynamics. Although per-capita meerkat mortality is subject to a component Allee effect, it contributes relatively little to observed variation in group dynamics, and other (conventionally density dependent) demographic rates - especially emigration - govern group dynamics. 6. Our findings highlight the need to consider demographic processes and density dependence in subpopulations before drawing conclusions about how behaviour affects population processes in socially complex systems. © 2011 The Authors. Journal of Animal Ecology © 2011 British Ecological Society.

Molecular structures and intramolecular dynamics of pentahalides

NASA Astrophysics Data System (ADS)

Ischenko, A. A.

2017-03-01

This paper reviews advances of modern gas electron diffraction (GED) method combined with high-resolution spectroscopy and quantum chemical calculations in studies of the impact of intramolecular dynamics in free molecules of pentahalides. Some recently developed approaches to the electron diffraction data interpretation, based on direct incorporation of the adiabatic potential energy surface parameters to the diffraction intensity are described. In this way, complementary data of different experimental and computational methods can be directly combined for solving problems of the molecular structure and its dynamics. The possibility to evaluate some important parameters of the adiabatic potential energy surface - barriers to pseudorotation and saddle point of intermediate configuration from diffraction intensities in solving the inverse GED problem is demonstrated on several examples. With increasing accuracy of the electron diffraction intensities and the development of the theoretical background of electron scattering and data interpretation, it has become possible to investigate complex nuclear dynamics in fluxional systems by the GED method. Results of other research groups are also included in the discussion.

Renewable fluid dynamic energy derived from aquatic animal locomotion.

PubMed

Dabiri, John O

2007-09-01

Aquatic animals swimming in isolation and in groups are known to extract energy from the vortices in environmental flows, significantly reducing muscle activity required for locomotion. A model for the vortex dynamics associated with this phenomenon is developed, showing that the energy extraction mechanism can be described by simple criteria governing the kinematics of the vortices relative to the body in the flow. In this way, we need not make direct appeal to the fluid dynamics, which can be more difficult to evaluate than the kinematics. Examples of these principles as exhibited in swimming fish and existing energy conversion devices are described. A benefit of the developed framework is that the potentially infinite-dimensional parameter space of the fluid-structure interaction is reduced to a maximum of eight combinations of three parameters. The model may potentially aid in the design and evaluation of unsteady aero- and hydrodynamic energy conversion systems that surpass the Betz efficiency limit of steady fluid dynamic energy conversion systems.

Expert performance in sport and the dynamics of talent development.

PubMed

Phillips, Elissa; Davids, Keith; Renshaw, Ian; Portus, Marc

2010-04-01

Research on expertise, talent identification and development has tended to be mono-disciplinary, typically adopting genocentric or environmentalist positions, with an overriding focus on operational issues. In this paper, the validity of dualist positions on sport expertise is evaluated. It is argued that, to advance understanding of expertise and talent development, a shift towards a multidisciplinary and integrative science focus is necessary, along with the development of a comprehensive multidisciplinary theoretical rationale. Here we elucidate dynamical systems theory as a multidisciplinary theoretical rationale for capturing how multiple interacting constraints can shape the development of expert performers. This approach suggests that talent development programmes should eschew the notion of common optimal performance models, emphasize the individual nature of pathways to expertise, and identify the range of interacting constraints that impinge on performance potential of individual athletes, rather than evaluating current performance on physical tests referenced to group norms.

Lasting monitoring of immune state in patients with coronary atherosclerosis

NASA Astrophysics Data System (ADS)

Malinova, Lidia I.; Denisova, Tatyana P.; Tuchin, Valery V.

2007-02-01

Immune state monitoring is an expensive, invasive and sometimes difficult necessity in patients with different disorders. Immune reaction dynamics study in patients with coronary atherosclerosis provides one of the leading components to complication development, clinical course prognosis and treatment and rehabilitation tactics. We've chosen intravenous glucose injection as metabolic irritant in the following four groups of patients: men with proved coronary atherosclerosis (CA), non insulin dependent diabetes mellitus (NIDDM), men hereditary burden by CA and NIDDM and practically healthy persons with longlivers in generation. Immune state parameters such as quantity of leukocytes and lymphocytes, circulating immune complexes levels, serum immunoglobulin levels, HLA antigen markers were studied at 0, 30 and 60 minutes during glucose loading. To obtain continues time function of studied parameters received data were approximated by polynomials of high degree with after going first derivatives. Time functions analyze elucidate principally different dynamics studied parameters in all chosen groups of patients, which couldn't be obtained from discontinuous data compare. Leukocyte and lymphocyte levels dynamics correlated HLA antigen markers in all studied groups. Analytical estimation of immune state in patients with coronary atherosclerosis shows the functional "margin of safety" of immune system state under glucose disturbance. Proposed method of analytical estimation also can be used in immune system monitoring in other groups of patients.

[Dynamic retraction microneurosurgery for the treatment of medial tentorial meningiomas].

PubMed

Du, W; Zhong, D; Lü, D; Li, J; Huang, H Y; Yang, J; Wu, Y T; Xia, H J; Tang, W Y; Sun, X C

2018-05-08

Objective: To investigate the effectiveness and clinical significance of dynamic retraction microneurosurgery for the treatment of medial tentorial meningiomas. Methods: From January 2011 to December 2016, a cohort of 28 patients with medial tentorial meningiomas were treated by microneurosurgery at the First Affiliated Hospital of Chongqing Medical University. Patients who treated intraoperatively with dynamic retraction surgery from January 2014 to December 2016 were assigned into dynamic retraction group, and those with fixed retractors intraoperatively from January 2011 to December 2013 were assigned into retractor group. The surgical approaches tailored in our patients were based on predominant direction of tumor extension. The extent of tumor resection was scored according to the Simpson's classification scale. Comparisons of tumor size, operation time, hospitalization time, retraction-related injury, tumor Simpson resection grade and Karnofsky Performance Scale(KPS) score six months after surgery were also made between two groups. Results: A total of 12 patients(retractor group) were treated with the use of self-retaining brain retractors intraoperatively and dynamic retraction surgical procedure was performed intraoperatively in 16 patients(dynamic retraction group). The difference between two groups with regard to sex, age, tumor size, operation time and tumor Simpson resection grade was not statistically significant(all P >0.05). The mean duration of hospital time was shorter in the dynamic retraction group than that in the retractor group(18.3 d±1.8 d vs 20.2 d±1.3 d, P =0.004). The dynamic retraction group had lower incidence of retraction-related injury compared with the retractor group(1/16 vs 6/12), P =0.022]. The dynamic retraction group had better neurological recovery rate with KPS >80 evaluated six months after surgery compared with the retractor group(14/16 vs 5/12, P =0.017). Conclusions: Dynamic retraction microneurosurgery for the treatment of medial tentorial meningiomas is feasible, which can obviate or reduce the amount of brain retraction needed, and may be of help in lowering the risk of postoperative neurological deficits and complications and leading to reduced hospitalization cost and improved surgical outcomes.

Muscle function in aged women in response to a water-based exercises program and progressive resistance training.

PubMed

Bento, Paulo Cesar Barauce; Rodacki, André Luiz Felix

2015-11-01

The purpose of the present study was to determine the effects of a water-based exercise program on muscle function compared with regular high-intensity resistance training. Older women (n = 87) were recruited from the local community. The inclusion criteria were, to be aged 60 years or older, able to walk and able to carry out daily living activities independently. Participants were randomly assigned to one of the following groups: water-based exercises (WBG), resistance training (RTG) or control (CG). The experimental groups carried out 12 weeks of an excise program performed on water or on land. The dynamic strength, the isometric peak, and rate of torque development for the lower limbs were assessed before and after interventions. The water-based program provided a similar improvement in dynamic strength in comparison with resistance training. The isometric peak torque increased around the hip and ankle joints in the water-based group, and around the knee joint in the resistance-training group (P < 0.05). The rate of torque development increased only in the water-based group around the hip extensors muscles (P < 0.05). Water-based programs constitute an attractive alternative to promote relevant strength gains using moderate loads and fast speed movements, which were also effective to improve the capacity to generate fast torques. © 2014 Japan Geriatrics Society.

A virtual team group process.

PubMed

Bell, Marnie; Robertson, Della; Weeks, Marlene; Yu, Deborah

2002-01-01

Virtual teams are a phenomenon of the Information Era and their existence in health care is anticipated to increase with technology enhancements such as telehealth and groupware. The mobilization and support of high performing virtual teams are important for leading knowledge-based health professionals in the 21st century. Using an adapted McGrath group development model, the four staged maturation process of a virtual team consisting of four masters students is explored in this paper. The team's development is analyzed addressing the interaction of technology with social and task dynamics. Throughout the project, leadership competencies of value to the group that emerged were demonstrated and incorporated into the development of a leadership competency assessment instrument. The demonstration of these competencies illustrated how they were valued and internalized by the group. In learning about the work of this virtual team, the reader will gain understanding of how leadership impacts virtual team performance.

Nest-Gallery Development and Caste Composition of Isolated Foraging Groups of the Drywood Termite, Incisitermes minor (Isoptera: Kalotermitidae)

PubMed Central

Himmi, S. Khoirul; Yoshimura, Tsuyoshi; Yanase, Yoshiyuki; Oya, Masao; Torigoe, Toshiyuki; Akada, Masanori; Imadzu, Setsuo

2016-01-01

An X-ray computed-tomographic examination of nest-gallery development from timbers naturally infested by foraging groups of Incisitermes minor colonies was conducted. This study documents the colonization process of I. minor to new timbers and how the isolated groups maintain their nest-gallery system. The results suggested that development of a nest-gallery within a suitable wood item is not random, but shows selection for softer substrate and other adaptations to the different timber environments. Stigmergic coordinations were expressed in dynamic changes of the nest-gallery system; indicated by fortification behavior in sealing and re-opening a tunnel approaching the outer edge of the timber, and accumulating fecal pellets in particular chambers located beneath the timber surface. The study also examines the caste composition of isolated groups to discover how I. minor sustains colonies with and without primary reproductives. PMID:27455332

[Adolescent arsonists--psychodynamics, family dynamics and attempt at framing a typology based on 40 expert opinions].

PubMed

Klosinski, G; Bertsch, S L

2001-02-01

Psychiatric, psychological and medical data of 40 adolescent firesetters are obtained from a retrospective analysis of expert opinions which have been drawn up by the Department of Child and Adolescent Psychiatry in Tübingen over a period of 16 years (1981-1997). This analysis mainly focusses on the patients' physical and psychosexual development, their social integration and competence and their family dynamics. It further concentrates on the psychic situation at the time of the offense, the reasons and motives given for firesetting (by the patient and by the expert) and specific psychological test results. According to the results three different characteristic groups can be found: 1st a group of offenders who have set fires to their parents' house, 2nd firesetters being member of the firebrigade, and 3rd an unspecific inhomogeneous group of firesetters.

Software engineering and automatic continuous verification of scientific software

NASA Astrophysics Data System (ADS)

Piggott, M. D.; Hill, J.; Farrell, P. E.; Kramer, S. C.; Wilson, C. R.; Ham, D.; Gorman, G. J.; Bond, T.

2011-12-01

Software engineering of scientific code is challenging for a number of reasons including pressure to publish and a lack of awareness of the pitfalls of software engineering by scientists. The Applied Modelling and Computation Group at Imperial College is a diverse group of researchers that employ best practice software engineering methods whilst developing open source scientific software. Our main code is Fluidity - a multi-purpose computational fluid dynamics (CFD) code that can be used for a wide range of scientific applications from earth-scale mantle convection, through basin-scale ocean dynamics, to laboratory-scale classic CFD problems, and is coupled to a number of other codes including nuclear radiation and solid modelling. Our software development infrastructure consists of a number of free tools that could be employed by any group that develops scientific code and has been developed over a number of years with many lessons learnt. A single code base is developed by over 30 people for which we use bazaar for revision control, making good use of the strong branching and merging capabilities. Using features of Canonical's Launchpad platform, such as code review, blueprints for designing features and bug reporting gives the group, partners and other Fluidity uers an easy-to-use platform to collaborate and allows the induction of new members of the group into an environment where software development forms a central part of their work. The code repositoriy are coupled to an automated test and verification system which performs over 20,000 tests, including unit tests, short regression tests, code verification and large parallel tests. Included in these tests are build tests on HPC systems, including local and UK National HPC services. The testing of code in this manner leads to a continuous verification process; not a discrete event performed once development has ceased. Much of the code verification is done via the "gold standard" of comparisons to analytical solutions via the method of manufactured solutions. By developing and verifying code in tandem we avoid a number of pitfalls in scientific software development and advocate similar procedures for other scientific code applications.

Dynamics of change in rat arterial pressure under conditions of immobilization

NASA Technical Reports Server (NTRS)

Yumatov, Y. A.; Skotselyas, Y. G.; Ivanona, L. I.

1980-01-01

Emotional stress developed in immobilized rats was shown to be accompanied by changes in the regulation of arterial pressure and the frequency of cardiac contractions. A group of adapting rats displayed definite resistance to emotional stress, while a group of rats incapable of adapting to acute emotional stress died with characteristics of cardiovascular insufficiency. The mechanisms providing resistance to emotional stress in numerous conflict situations were analyzed.

A modified Lotka-Volterra model for the evolution of coordinate symbiosis in energy enterprise

NASA Astrophysics Data System (ADS)

Zhou, Li; Wang, Teng; Lyu, Xiaohuan; Yu, Jing

2018-02-01

Recent developments in energy markets make the operating industries more dynamic and complex, and energy enterprises cooperate more closely in the industrial chain and symbiosis. In order to further discuss the evolution of coordinate symbiosis in energy enterprises, a modified Lotka-Volterra equation is introduced to develop a symbiosis analysis model of energy groups. According to the equilibrium and stability analysis, a conclusion is obtained that if the upstream energy group and the downstream energy group are in symbiotic state, the growth of their utility will be greater than their independent value. Energy enterprises can get mutual benefits and positive promotions in industrial chain by their cooperation.

Development of One-Group and Two-Group Interfacial Area Transport Equation

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

Ishii, M.; Kim, S.

A dynamic approach employing the interfacial area transport equation is presented to replace the static flow regime dependent correlations for the interfacial area concentration. The current study derives the transport equations for the bubble number, volume, and interfacial area concentration. Accounting for the substantial differences in the transport phenomena of various sizes of bubbles, both one-group and two-group interfacial area transport equations are developed along with the necessary constitutive relations. The framework for the complicated source and sink terms in the two-group transport equation is also presented by identifying the major intragroup and intergroup bubble interaction mechanisms. In view ofmore » evaluating the theoretical model, the one-group interfacial area transport equation is benchmarked based on the available data obtained in a wide range of air-water bubbly flow in round tubes of various diameters. In general, the results show good agreement within the measurement error of {+-}10%.« less

Dynamic Mapping of Cortical Development before and after the Onset of Pediatric Bipolar Illness

ERIC Educational Resources Information Center

Gogtay, Nitin; Ordonez, Anna; Herman, David H.; Hayashi, Kiralee M.; Greenstein, Deanna; Vaituzis, Cathy; Lenane, Marge; Clasen, Liv; Sharp, Wendy; Giedd, Jay N.; Jung, David; Nugent, Tom F., III; Toga, Arthur W.; Leibenluft, Ellen; Thompson, Paul M.; Rapoport, Judith L.

2007-01-01

Background: There are, to date, no pre-post onset longitudinal imaging studies of bipolar disorder at any age. We report the first prospective study of cortical brain development in pediatric bipolar illness for 9 male children, visualized before and after illness onset. Method: We contrast this pattern with that observed in a matched group of…

Ties That Bond: Youth Sport as a Vehicle for Social Identity and Positive Youth Development

ERIC Educational Resources Information Center

Bruner, Mark W.; Balish, Shea M.; Forrest, Christopher; Brown, Sarah; Webber, Kristine; Gray, Emily; McGuckin, Matthew; Keats, Melanie R.; Rehman, Laurene; Shields, Christopher A.

2017-01-01

An emerging area of research has focused on understanding how the group dynamics of a sport team influence positive youth development (PYD). The identities that youth form through their membership in sport teams (i.e., social identities) have been found to influence teammate behavior and team performance. Yet, minimal work exists on social…

On-the-Spot Course in Maseru, Lesotho on Income-Generating Projects for Rural Women: Framework of Community Development. July 10-30, 1983. Report.

ERIC Educational Resources Information Center

Mount Carmel International Training Centre for Community Development, Haifa (Israel).

This report describes a community development course focusing on income-generating projects for rural women. The first section outlines the schedule of activities for each day of the 16-day course. The second section defines course objectives, including purpose and methodology, planning, group dynamics, cooperation, communication, negotiation, and…

Opinion dynamics within a virtual small group: the stubbornness effect

NASA Astrophysics Data System (ADS)

Guazzini, Andrea; Cini, Alessandro; Bagnoli, Franco; Ramasco, José

2015-09-01

The modeling of opinion dynamics is social systems has attracted a good deal of attention in the last decade. Even though based on intuition and observation, the mechanisms behind many of these models need solid empirical grounding. In this work, we investigate the relation among subjective variables (such as the personality), the dynamics of the affinity network dynamics, the communication patterns emerging throughout the social interactions and the opinions dynamics in a series of experiments with five small groups of ten people each. In order to ignite the discussion, the polemic topic of animal experimentation was proposed. The groups essentially polarized in two factions with a set of stubborn individuals (those not changing their opinions in time) playing the role of anchors. Our results suggest that the different layers present in the group dynamics (i.e., individual level, group dynamics and meso-communication) are deeply intermingled, specifically the stubbornness effect appears to be related to the dynamical features of the network topologies, and only in an undirected way to the personality of the participants.

The dynamics of radical right-wing populist party preferences and perceived group threat: A comparative panel analysis of three competing hypotheses in the Netherlands and Germany.

PubMed

Berning, Carl C; Schlueter, Elmar

2016-01-01

Existing cross-sectional research considers citizens' preferences for radical right-wing populist (RRP) parties to be centrally driven by their perception that immigrants threaten the well-being of the national ingroup. However, longitudinal evidence for this relationship is largely missing. To remedy this gap in the literature, we developed three competing hypotheses to investigate: (a) whether perceived group threat is temporally prior to RRP party preferences, (b) whether RRP party preferences are temporally prior to perceived group threat, or (c) whether the relation between perceived group threat and RRP party preferences is bidirectional. Based on multiwave panel data from the Netherlands for the years 2008-2013 and from Germany spanning the period 1994-2002, we examined the merits of these hypotheses using autoregressive cross-lagged structural equation models. The results show that perceptions of threatened group interests precipitate rather than follow citizens' preferences for RRP parties. These findings help to clarify our knowledge of the dynamic structure underlying RRP party preferences. Copyright © 2015 Elsevier Inc. All rights reserved.

On the origin of biological construction, with a focus on multicellularity.

PubMed

van Gestel, Jordi; Tarnita, Corina E

2017-10-17

Biology is marked by a hierarchical organization: all life consists of cells; in some cases, these cells assemble into groups, such as endosymbionts or multicellular organisms; in turn, multicellular organisms sometimes assemble into yet other groups, such as primate societies or ant colonies. The construction of new organizational layers results from hierarchical evolutionary transitions, in which biological units (e.g., cells) form groups that evolve into new units of biological organization (e.g., multicellular organisms). Despite considerable advances, there is no bottom-up, dynamical account of how, starting from the solitary ancestor, the first groups originate and subsequently evolve the organizing principles that qualify them as new units. Guided by six central questions, we propose an integrative bottom-up approach for studying the dynamics underlying hierarchical evolutionary transitions, which builds on and synthesizes existing knowledge. This approach highlights the crucial role of the ecology and development of the solitary ancestor in the emergence and subsequent evolution of groups, and it stresses the paramount importance of the life cycle: only by evaluating groups in the context of their life cycle can we unravel the evolutionary trajectory of hierarchical transitions. These insights also provide a starting point for understanding the types of subsequent organizational complexity. The central research questions outlined here naturally link existing research programs on biological construction (e.g., on cooperation, multilevel selection, self-organization, and development) and thereby help integrate knowledge stemming from diverse fields of biology.

Trypanosoma cruzi: effects of azadirachtin and ecdysone on the dynamic development in Rhodnius prolixus larvae.

PubMed

Cortez, M R; Provençano, A; Silva, C E; Mello, C B; Zimmermann, L T; Schaub, G A; Garcia, E S; Azambuja, P; Gonzalez, M S

2012-07-01

The effects of azadirachtin and ecdysone on the Trypanosoma cruzi population in the Rhodnius prolixus gut were investigated. T. cruzi were rarely found in the gut compartments of azadirachtin-treated larvae. High parasite numbers were observed in the stomach of the control and ecdysone groups until 10 days after treatment and in the small intestine and rectum until 25 days after treatment. High percentages of round forms developed in the stomachs of all groups, whereas azadirachtin blocked the development of protozoan intermediate forms. This effect was counteracted by ecdysone therapy. In the small intestine and rectum, epimastigotes predominated for all groups, but more of their intermediates developed in the control and ecdysone groups. Azadirachtin supported the development of round forms and their intermediates into trypomastigotes. In the rectum, trypomastigotes did not develop in the azadirachtin group and developed much later after ecdysone therapy. The parallel between the effects of azadirachtin and ecdysone on the host and parasite development is discussed on the basis of the present results because ecdysone appears to act directly or indirectly in determining the synchronic development of T. cruzi forms from round to epimastigotes, but not metacyclic trypomastigotes, in the invertebrate vector. Copyright © 2012 Elsevier Inc. All rights reserved.

A New Approach on the Long Term Dynamics of NEO's Under Yarkovsky Effect.

NASA Astrophysics Data System (ADS)

Peláez, Jesús; Urrutxua, Hodei; Bombardelli, Claudio; Perez-Grande, Isabel

2011-12-01

A classical approach to the many-body problem is that of using special perturbation methods. Nowadays and due to the availability of high-speed computers is an essential tool in Space Dynamics which exhibits a great advantage: it is applicable to any orbit involving any number of bodies and all sorts of astrodynamical problems, especially when these problems fall into regions in which general perturbation theories are absent. One such case is, for example, that Near Earth Objects (NEO's) dynamics. In this field, the Group of Tether Dynamics of UPM (GDT) has developed a new regularisation scheme - called DROMO - which is characterised by only 8 ODE. This new regularisation scheme allows a new approach to the dynamics of NEO's in the long term, specially appropriated to consider the influence of the anisotropic thermal emission (Yarkovsky and YORP effects) on the dynamics. A new project, called NEODROMO, has been started in GDT that aims to provide a reliable tool for the long term dynamics of NEO's.

Strength and Power Training Effects on Lower Limb Force, Functional Capacity, and Static and Dynamic Balance in Older Female Adults.

PubMed

Lopes, Paula Born; Pereira, Gleber; Lodovico, Angélica; Bento, Paulo C B; Rodacki, André L F

2016-03-03

It has been proposed that muscle power is more effective to prevent falls than muscle force production capacity, as rapid reactions are required to allow the postural control. This study aimed to compare the effects of strength and power training on lower limb force, functional capacity, and static and dynamic balance in older female adults. Thirty-seven volunteered healthy women had been allocated into the strength-training group (n = 14; 69 ± 7.3 years, 155 ± 5.6 cm, 72 ± 9.7 kg), the power-training group (n = 12; 67 ± 7.4 years, 153 ± 5.5 cm, 67.2 ± 7 kg), and control group (n = 11; 65 ± 3.1 years, 154 ± 5.6 cm, 70.9 ± 3 kg). After 12 weeks of training, the strength-training and power-training groups increased significantly maximum dynamic strength (29% and 27%), isometric strength (26% and 37%), and step total time (13% and 14%, dynamic balance), respectively. However, only the power-training group increased the rate of torque development (55%) and the functional capacity in 30-second chair stand (22%) and in time up and go tests (-10%). Empirically, power training may reduce the risk of injuries due to lower loads compared to strength training, and consequently, the physical effort demand during the training session is lower. Therefore, power training should be recommended as attractive training stimuli to improve lower limb force, functional capacity, and postural control of older female adults.

Development and evaluation of a self-regulating alternating pressure air cushion.

PubMed

Nakagami, Gojiro; Sanada, Hiromi; Sugama, Junko

2015-03-01

To investigate the effect of alternating air cells of a newly developed dynamic cushion on interface pressure and tissue oxygenation levels. This cross-over experimental study included 19 healthy volunteers. The dynamic cushion used has an automatic self-regulating alternating pressure air-cell system with 35 small and four large air cells for maintaining posture while seated. This cushion also has 17 bottoming-out detectors that automatically inflate the air cells to release a high interface pressure. To assess the effect of this alternating system, participants sat on the new cushion with an alternating system or static system for 30 min and then performed push-ups. The interface pressure was monitored by pressure-sensitive and conductive ink film sensors and tissue oxygenation levels were monitored by near-infrared spectroscopy. A reactive hyperaemia indicator was calculated using tissue oxygenation levels as an outcome measure. The peak interface pressure was not significantly different between the groups. The reactive hyperaemia indicator was significantly higher in the static group than in the alternating group. An alternating system has beneficial effects on blood oxygenation levels without increasing interface pressure. Therefore, our new cushion is promising for preventing pressure ulcers with patients with limited ability to perform push-ups. Implications for Rehabilitation A dynamic cushion was developed, which consists of a uniquely-designed air-cell layout, detectors for bottoming out, and an alternating system with multiple air-cell lines. The alternating system did not increase interface pressure and it significantly reduced reactive hyperaemia after 30 min of sitting in healthy volunteers. This cushion is a new option for individuals who require stable posture but have limitations in performing scheduled push-ups for prevention of pressure ulcers.

Growth plate cartilage shows different strain patterns in response to static versus dynamic mechanical modulation.

PubMed

Kaviani, Rosa; Londono, Irene; Parent, Stefan; Moldovan, Florina; Villemure, Isabelle

2016-08-01

Longitudinal growth of long bones and vertebrae occurs in growth plate cartilage. This process is partly regulated by mechanical forces, which are one of the underlying reasons for progression of growth deformities such as idiopathic adolescent scoliosis and early-onset scoliosis. This concept of mechanical modulation of bone growth is also exploited in the development of fusionless treatments of these deformities. However, the optimal loading condition for the mechanical modulation of growth plate remains to be identified. The objective of this study was to evaluate the effects of in vitro static versus dynamic modulation and of dynamic loading parameters, such as frequency and amplitude, on the mechanical responses and histomorphology of growth plate explants. Growth plate explants from distal ulnae of 4-week-old swines were extracted and randomly distributed among six experimental groups: baseline ([Formula: see text]), control ([Formula: see text]), static ([Formula: see text]) and dynamic ([Formula: see text]). For static and dynamic groups, mechanical modulation was performed in vitro using an Indexed CartiGen bioreactor. A stress relaxation test combined with confocal microscopy and digital image correlation was used to characterize the mechanical responses of each explant in terms of peak stress, equilibrium stress, equilibrium modulus of elasticity and strain pattern. Histomorphometrical measurements were performed on toluidine blue tissue sections using a semi-automatic custom-developed MATLAB toolbox. Results suggest that compared to dynamic modulation, static modulation changes the strain pattern of the tissue and thus is more detrimental for tissue biomechanics, while the histomorphological parameters are not affected by mechanical modulation. Also, under dynamic modulation, changing the frequency or amplitude does not affect the biomechanical response of the tissue. Results of this study will be useful in finding optimal and non-damaging parameters for the mechanical modulation of growth plate in fusionless treatments.

Measuring Group Work Dynamics and Its Relation with L2 Learners' Task Motivation and Language Production

ERIC Educational Resources Information Center

Poupore, Glen

2016-01-01

While learners of a second language (L2) are increasingly interacting in small groups as part of a communicative methodological paradigm, very few studies have investigated the social dynamics that occur in such groups. The aim of this study is to introduce a group work dynamic measuring instrument and to investigate the relationship between group…

Direct dynamics simulations of the unimolecular dissociation of dioxetane: Probing the non-RRKM dynamics

NASA Astrophysics Data System (ADS)

Malpathak, Shreyas; Ma, Xinyou; Hase, William L.

2018-04-01

In a previous UB3LYP/6-31G* direct dynamics simulation, non-Rice-Ramsperger-Kassel-Marcus (RRKM) unimolecular dynamics was found for vibrationally excited 1,2-dioxetane (DO); [R. Sun et al., J. Chem. Phys. 137, 044305 (2012)]. In the work reported here, these dynamics are studied in more detail using the same direct dynamics method. Vibrational modes of DO were divided into 4 groups, based on their characteristic motions, and each group excited with the same energy. To compare with the dynamics of these groups, an additional group of trajectories comprising a microcanonical ensemble was also simulated. The results of these simulations are consistent with the previous study. The dissociation probability, N(t)/N(0), for these excitation groups were all different. Groups A, B, and C, without initial excitation in the O-O stretch reaction coordinate, had a time lag to of 0.25-1.0 ps for the first dissociation to occur. Somewhat surprisingly, the C-H stretch Group A and out-of-plane motion Group C excitations had exponential dissociation probabilities after to, with a rate constant ˜2 times smaller than the anharmonic RRKM value. Groups B and D, with excitation of the H-C-H bend and wag, and ring bend and stretch modes, respectively, had bi-exponential dissociation probabilities. For Group D, with excitation localized in the reaction coordinate, the initial rate constant is ˜7 times larger than the anharmonic RRKM value, substantial apparent non-RRKM dynamics. N(t)/N(0) for the random excitation trajectories was non-exponential, indicating intrinsic non-RRKM dynamics. For the trajectory integration time of 13.5 ps, 9% of these trajectories did not dissociate in comparison to the RRKM prediction of 0.3%. Classical power spectra for these trajectories indicate they have regular intramolecular dynamics. The N(t)/N(0) for the excitation groups are well described by a two-state coupled phase space model. From the intercept of N(t)/N(0) with random excitation, the anharmonic correction to the RRKM rate constant is approximately a factor of 1.5.

Rationale and Design of the Feeding Dynamic Intervention (FDI) Study for Self-Regulation of Energy Intake in Preschoolers

PubMed Central

Eneli, Ihuoma U.; Tylka, Tracy L.; Hummel, Jessica; Watowicz, Rosanna P.; Perez, Susana A.; Kaciroti, Niko; Lumeng, Julie C.

2015-01-01

In 2011, the Institute of Medicine Early Childhood Prevention Policies Report identified feeding dynamics as an important focus area for childhood obesity prevention and treatment. Feeding dynamics include two central components: (1) caregiver feeding practices (i.e., determining how, when, where, and what they feed their children) and (2) child eating behaviors (i.e., determining how much and what to eat from what food caregivers have provided). Although there has been great interest in overweight and obesity prevention and treatment in young children, they have not focused comprehensively on feeding dynamics. Interventions on feeding dynamics that reduce caregivers’ excessive controlling and restrictive feeding practices and encourage the development of children’s self-regulation of energy intake may hold promise for tackling childhood obesity especially in the young child but currently lack an evidence base. This manuscript describes the rationale and design for a randomized controlled trial designed to compare a group of mothers and their 3-to 5-year old children who received an intervention focused primarily on feeding dynamics called the Feeding Dynamic Intervention (FDI) with a Wait-list Control Group (WLC). The primary aim of the study will be to investigate the efficacy of the FDI for decreasing Eating in the Absence of Hunger (EAH) and improving energy compensation (COMPX). The secondary aim will be to examine the effect of the FDI in comparison to the WLC on maternal self-reported feeding practices and child satiety responsiveness. PMID:25616192

Space life support engineering program

NASA Technical Reports Server (NTRS)

Seagrave, Richard C.

1992-01-01

A comprehensive study to develop software to simulate the dynamic operation of water reclamation systems in long-term closed-loop life support systems is being carried out as part of an overall program for the design of systems for a moon station or a Mars voyage. This project is being done in parallel with a similar effort in the Department of Chemistry to develop durable accurate low-cost sensors for monitoring of trace chemical and biological species in recycled water supplies. Aspen-Plus software is being used on a group of high-performance work stations to develop the steady state descriptions for a number of existing technologies. Following completion, a dynamic simulation package will be developed for determining the response of such systems to changes in the metabolic needs of the crew and to upsets in system hardware performance.

Spatiotemporal Dynamics of Oligofructan Metabolism and Suggested Functions in Developing Cereal Grains

PubMed Central

Peukert, Manuela; Thiel, Johannes; Mock, Hans-Peter; Marko, Doris; Weschke, Winfriede; Matros, Andrea

2016-01-01

Oligofructans represent one of the most important groups of sucrose-derived water–soluble carbohydrates in the plant kingdom. In cereals, oligofructans accumulate in above ground parts of the plants (stems, leaves, seeds) and their biosynthesis leads to the formation of both types of glycosidic linkages [β(2,1); β(2,6)-fructans] or mixed patterns. In recent studies, tissue- and development- specific distribution patterns of the various oligofructan types in cereal grains have been shown, which are possibly related to the different phases of grain development, such as cellular differentiation of grain tissues and storage product accumulation. Here, we summarize the current knowledge about oligofructan biosynthesis and accumulation kinetics in cereal grains. We focus on the spatiotemporal dynamics and regulation of oligofructan biosynthesis and accumulation in developing barley grains (deduced from a combination of metabolite, transcript and proteome analyses). Finally, putative physiological functions of oligofructans in developing grains are discussed. PMID:26834760

Effective user management with high strength crypto -key in dynamic group environment in cloud

NASA Astrophysics Data System (ADS)

Kumar, P. J.; Suganya, P.; Karthik, G.

2017-11-01

Cloud Clusters consists of various collections of files which are being accessed by multiple users of Cloud. The users are managed as a group and the association of the user to a particular group is dynamic in nature. Every group has a manager who handles the membership of a user to a particular group by issuing keys for encryption and decryption. Due to the dynamic nature of a user he/she may leave the group very frequently. But an attempt can be made by the user who has recently left the group to access a file maintained by that group. Key distribution becomes a critical issue while the behavior of the user is dynamic. Existing techniques to manage the users of group in terms of security and key distribution has been investigated so that to arrive at an objective to identify the scopes to increase security and key management scheme in cloud. The usage of various key combinations to measure the strength of security and efficiency of user management in dynamic cloud environment has been investigated.

Combining two potential causes of metalloproteinase secretion causes abdominal aortic aneurysms in rats: a new experimental model

PubMed Central

Mata, Karina M; Prudente, Paula S; Rocha, Fabio S; Prado, Cibele M; Floriano, Elaine M; Elias, Jorge; Rizzi, Elen; Gerlach, Raquel F; Rossi, Marcos A; Ramos, Simone G

2011-01-01

Progress in understanding the pathophysiology of abdominal aortic aneurysms (AAA) is dependent in part on the development and application of effective animal models that recapitulate key aspects of the disease. The objective was to produce an experimental model of AAA in rats by combining two potential causes of metalloproteinase (MMP) secretion: inflammation and turbulent blood flow. Male Wistar rats were randomly divided in four groups: Injury, Stenosis, Aneurysm and Control (40/group). The Injury group received a traumatic injury to the external aortic wall. The Stenosis group received an extrinsic stenosis at a corresponding location. The Aneurysm group received both the injury and stenosis simultaneously, and the Control group received a sham operation. Animals were euthanized at days 1, 3, 7 and 15. Aorta and/or aneurysms were collected and the fragments were fixed for morphologic, immunohistochemistry and morphometric analyses or frozen for MMP assays. AAAs had developed by day 3 in 60–70% of the animals, reaching an aortic dilatation ratio of more than 300%, exhibiting intense wall remodelling initiated at the adventitia and characterized by an obvious inflammatory infiltrate, mesenchymal proliferation, neoangiogenesis, elastin degradation and collagen deposition. Immunohistochemistry and zymography studies displayed significantly increased expressions of MMP-2 and MMP-9 in aneurysm walls compared to other groups. The haemo-dynamic alterations caused by the stenosis may have provided additional contribution to the MMPs liberation. This new model illustrated that AAA can be multifactorial and confirmed the key roles of MMP-2 and MMP-9 in this dynamic remodelling process. PMID:21039990

The impact of chief executive officer personality on top management team dynamics:one mechanism by which leadership affects organizational performance.

PubMed

Peterson, Randall S; Smith, D Brent; Martorana, Paul V; Owens, Pamela D

2003-10-01

This article explores 1 mechanism by which leader personality affects organizational performance. The authors hypothesized and tested the effects of leader personality on the group dynamics of the top management team (TMT) and of TMT dynamics on organizational performance. To test their hypotheses, the authors used the group dynamics q-sort method, which is designed to permit rigorous, quantitative comparisons of data derived from qualitative sources. Results from independent observations of chief executive officer (CEO) personality and TMT dynamics for 17 CEOs supported the authors' hypothesized relationships both between CEO personality and TMT group dynamics and between TMT dynamics and organizational performance.

Effect of somatosensory and neurofeedback training on balance in older healthy adults: a preliminary investigation.

PubMed

Azarpaikan, Atefeh; Taheri Torbati, Hamidreza

2017-10-23

The aim of this study was to assess the effectiveness of balance training with somatosensory and neurofeedback training on dynamic and static balance in healthy, elderly adults. The sample group consisted of 45 healthy adults randomly assigned to one of the three test groups: somatosensory, neurofeedback, and a control. Individualization of the balance program started with pre-tests for static and dynamic balances. Each group had 15- and 30-min training sessions. All groups were tested for static (postural stability) and dynamic balances (Berg Balance Scale) in acquisition and transfer tests (fall risk of stability and timed up and go). Improvements in static and dynamic balances were assessed by somatosensory and neurofeedback groups and then compared with the control group. Results indicated significant improvements in static and dynamic balances in both test groups in the acquisition test. Results revealed a significant improvement in the transfer test in the neurofeedback and somatosensory groups, in static and dynamic conditions, respectively. The findings suggest that these methods of balance training had a significant influence on balance. Both the methods are appropriate to prevent falling in adults. Neurofeedback training helped the participants to learn static balance, while somatosensory training was effective on dynamic balance learning. Further research is needed to assess the effects of longer and discontinuous stimulation with somatosensory and neurofeedback training on balance in elderly adults.

Devices and tasks involved in the objective assessment of standing dynamic balancing - A systematic literature review.

PubMed

Petró, Bálint; Papachatzopoulou, Alexandra; Kiss, Rita M

2017-01-01

Static balancing assessment is often complemented with dynamic balancing tasks. Numerous dynamic balancing assessment methods have been developed in recent decades with their corresponding balancing devices and tasks. The aim of this systematic literature review is to identify and categorize existing objective methods of standing dynamic balancing ability assessment with an emphasis on the balancing devices and tasks being used. Three major scientific literature databases (Science Direct, Web of Science, PLoS ONE) and additional sources were used. Studies had to use a dynamic balancing device and a task described in detail. Evaluation had to be based on objectively measureable parameters. Functional tests without instrumentation evaluated exclusively by a clinician were excluded. A total of 63 articles were included. The data extracted during full-text assessment were: author and date; the balancing device with the balancing task and the measured parameters; the health conditions, size, age and sex of participant groups; and follow-up measurements. A variety of dynamic balancing assessment devices were identified and categorized as 1) Solid ground, 2) Balance board, 3) Rotating platform, 4) Horizontal translational platform, 5) Treadmill, 6) Computerized Dynamic Posturography, and 7) Other devices. The group discrimination ability of the methods was explored and the conclusions of the studies were briefly summarized. Due to the wide scope of this search, it provides an overview of balancing devices and do not represent the state-of-the-art of any single method. The identified dynamic balancing assessment methods are offered as a catalogue of candidate methods to complement static assessments used in studies involving postural control.

Micro turbine engines for drones propulsion

NASA Astrophysics Data System (ADS)

Dutczak, J.

2016-09-01

Development of micro turbine engines began from attempts of application of that propulsion source by group of enthusiasts of aviation model making. Nowadays, the domain of micro turbojet engines is treated on a par with “full size” aviation constructions. The dynamic development of these engines is caused not only by aviation modellers, but also by use of micro turbojet engines by army to propulsion of contemporary drones, i.e. Unmanned Aerial Vehicles (UAV) or Unmanned Aerial Systems (UAS). On the base of selected examples the state of art in the mentioned group of engines has been presented in the article.

Improving plant functional groups for dynamic models of biodiversity: at the crossroads between functional and community ecology

PubMed Central

Isabelle, Boulangeat; Pauline, Philippe; Sylvain, Abdulhak; Roland, Douzet; Luc, Garraud; Sébastien, Lavergne; Sandra, Lavorel; Jérémie, Van Es; Pascal, Vittoz; Wilfried, Thuiller

2013-01-01

The pace of on-going climate change calls for reliable plant biodiversity scenarios. Traditional dynamic vegetation models use plant functional types that are summarized to such an extent that they become meaningless for biodiversity scenarios. Hybrid dynamic vegetation models of intermediate complexity (hybrid-DVMs) have recently been developed to address this issue. These models, at the crossroads between phenomenological and process-based models, are able to involve an intermediate number of well-chosen plant functional groups (PFGs). The challenge is to build meaningful PFGs that are representative of plant biodiversity, and consistent with the parameters and processes of hybrid-DVMs. Here, we propose and test a framework based on few selected traits to define a limited number of PFGs, which are both representative of the diversity (functional and taxonomic) of the flora in the Ecrins National Park, and adapted to hybrid-DVMs. This new classification scheme, together with recent advances in vegetation modeling, constitutes a step forward for mechanistic biodiversity modeling. PMID:24403847

osni.info-Using free/libre/open source software to build a virtual international community for open source nursing informatics.

PubMed

Oyri, Karl; Murray, Peter J

2005-12-01

Many health informatics organizations seem to be slow to take up the advantages of dynamic, web-based technologies for providing services to, and interaction with, their members; these are often the very technologies they promote for use within healthcare environments. This paper aims to introduce some of the many free/libre/open source (FLOSS) applications that are now available to develop interactive websites and dynamic online communities as part of the structure of health informatics organizations, and to show how the Open Source Nursing Informatics Working Group (OSNI) of the special interest group in nursing informatics of the International Medical Informatics Association (IMIA-NI) is using some of these tools to develop an online community of nurse informaticians through their website, at . Some background introduction to FLOSS applications is used for the benefit of those less familiar with such tools, and examples of some of the FLOSS content management systems (CMS) being used by OSNI are described. The experiences of the OSNI will facilitate a knowledgeable nursing contribution to the wider discussions on the applications of FLOSS within health and healthcare, and provides a model that many other groups could adopt.

Coarse-grained molecular dynamics simulations for giant protein-DNA complexes

NASA Astrophysics Data System (ADS)

Takada, Shoji

Biomolecules are highly hierarchic and intrinsically flexible. Thus, computational modeling calls for multi-scale methodologies. We have been developing a coarse-grained biomolecular model where on-average 10-20 atoms are grouped into one coarse-grained (CG) particle. Interactions among CG particles are tuned based on atomistic interactions and the fluctuation matching algorithm. CG molecular dynamics methods enable us to simulate much longer time scale motions of much larger molecular systems than fully atomistic models. After broad sampling of structures with CG models, we can easily reconstruct atomistic models, from which one can continue conventional molecular dynamics simulations if desired. Here, we describe our CG modeling methodology for protein-DNA complexes, together with various biological applications, such as the DNA duplication initiation complex, model chromatins, and transcription factor dynamics on chromatin-like environment.

Dynamic fractal signature dissimilarity analysis for therapeutic response assessment using dynamic contrast-enhanced MRI

PubMed Central

Wang, Chunhao; Subashi, Ergys; Yin, Fang-Fang; Chang, Zheng

2016-01-01

Purpose: To develop a dynamic fractal signature dissimilarity (FSD) method as a novel image texture analysis technique for the quantification of tumor heterogeneity information for better therapeutic response assessment with dynamic contrast-enhanced (DCE)-MRI. Methods: A small animal antiangiogenesis drug treatment experiment was used to demonstrate the proposed method. Sixteen LS-174T implanted mice were randomly assigned into treatment and control groups (n = 8/group). All mice received bevacizumab (treatment) or saline (control) three times in two weeks, and one pretreatment and two post-treatment DCE-MRI scans were performed. In the proposed dynamic FSD method, a dynamic FSD curve was generated to characterize the heterogeneity evolution during the contrast agent uptake, and the area under FSD curve (AUCFSD) and the maximum enhancement (MEFSD) were selected as representative parameters. As for comparison, the pharmacokinetic parameter Ktrans map and area under MR intensity enhancement curve AUCMR map were calculated. Besides the tumor’s mean value and coefficient of variation, the kurtosis, skewness, and classic Rényi dimensions d1 and d2 of Ktrans and AUCMR maps were evaluated for heterogeneity assessment for comparison. For post-treatment scans, the Mann–Whitney U-test was used to assess the differences of the investigated parameters between treatment/control groups. The support vector machine (SVM) was applied to classify treatment/control groups using the investigated parameters at each post-treatment scan day. Results: The tumor mean Ktrans and its heterogeneity measurements d1 and d2 values showed significant differences between treatment/control groups in the second post-treatment scan. In contrast, the relative values (in reference to the pretreatment value) of AUCFSD and MEFSD in both post-treatment scans showed significant differences between treatment/control groups. When using AUCFSD and MEFSD as SVM input for treatment/control classification, the achieved accuracies were 93.8% and 93.8% at first and second post-treatment scan days, respectively. In comparison, the classification accuracies using d1 and d2 of Ktrans map were 87.5% and 100% at first and second post-treatment scan days, respectively. Conclusions: As quantitative metrics of tumor contrast agent uptake heterogeneity, the selected parameters from the dynamic FSD method accurately captured the therapeutic response in the experiment. The potential application of the proposed method is promising, and its addition to the existing DCE-MRI techniques could improve DCE-MRI performance in early assessment of treatment response. PMID:26936718

Addressing group dynamics in a brief motivational intervention for college student drinkers.

PubMed

Faris, Alexander S; Brown, Janice M

2003-01-01

Previous research indicates that brief motivational interventions for college student drinkers may be less effective in group settings than individual settings. Social psychological theories about counterproductive group dynamics may partially explain this finding. The present study examined potential problems with group motivational interventions by comparing outcomes from a standard group motivational intervention (SGMI; n = 25), an enhanced group motivational intervention (EGMI; n = 27) designed to suppress counterproductive processes, and a no intervention control (n = 23). SGMI and EGMI participants reported disruptive group dynamics as evidenced by low elaboration likelihood, production blocking, and social loafing, though the level of disturbance was significantly lower for EGMI individuals (p = .001). Despite counteracting group dynamics in the EGMI condition, participants in the two interventions were statistically similar in post-intervention problem recognition and future drinking intentions. The results raise concerns over implementing individually-based interventions in group settings without making necessary adjustments.

Technology Integration (Task 20) Aeroservoelastic Modeling and Design Studies. Part A; Evaluation of Aeroservoelastic Effects on Flutter and Dynamic Gust Response

NASA Technical Reports Server (NTRS)

Nagaraja, K. S.; Kraft, R. H.

1999-01-01

The HSCT Flight Controls Group has developed longitudinal control laws, utilizing PTC aeroelastic flexible models to minimize aeroservoelastic interaction effects, for a number of flight conditions. The control law design process resulted in a higher order controller and utilized a large number of sensors distributed along the body for minimizing the flexibility effects. Processes were developed to implement these higher order control laws for performing the dynamic gust loads and flutter analyses. The processes and its validation were documented in Reference 2, for selected flight condition. The analytical results for additional flight conditions are presented in this document for further validation.

How do Small Groups Promote Behaviour Change? An Integrative Conceptual Review of Explanatory Mechanisms.

PubMed

Borek, Aleksandra J; Abraham, Charles

2018-03-01

Small groups are used to promote health, well-being, and personal change by altering members' perceptions, beliefs, expectations, and behaviour patterns. An extensive cross-disciplinary literature has articulated and tested theories explaining how such groups develop, function, and facilitate change. Yet these theoretical understandings are rarely applied in the development, description, and evaluation of health-promotion, group-based, behaviour-change interventions. Medline database, library catalogues, search engines, specific journals and reference lists were searched for relevant texts. Texts were reviewed for explanatory concepts or theories describing change processes in groups, which were integrated into the developing conceptual structure. This was designed to be a parsimonious conceptual framework that could be applied to design and delivery. Five categories of interacting processes and concepts were identified and defined: (1) group development processes, (2) dynamic group processes, (3) social change processes, (4) personal change processes, and (5) group design and operating parameters. Each of these categories encompasses a variety of theorised mechanisms explaining individual change in small groups. The final conceptual model, together with the design issues and practical recommendations derived from it, provides a practical basis for linking research and theory explaining group functioning to optimal design of group-based, behaviour-change interventions. © 2018 The Authors. Applied Psychology: Health and Well-Being published by John Wiley & Sons Ltd on behalf of International Association of Applied Psychology.

Dynamical spin accumulation in large-spin magnetic molecules

NASA Astrophysics Data System (ADS)

Płomińska, Anna; Weymann, Ireneusz; Misiorny, Maciej

2018-01-01

The frequency-dependent transport through a nanodevice containing a large-spin magnetic molecule is studied theoretically in the Kondo regime. Specifically, the effect of magnetic anisotropy on dynamical spin accumulation is of primary interest. Such accumulation arises due to finite components of frequency-dependent conductance that are off diagonal in spin. Here, employing the Kubo formalism and the numerical renormalization group method, we demonstrate that the dynamical transport properties strongly depend on the relative orientation of spin moments in electrodes of the device, as well as on intrinsic parameters of the molecule. In particular, the effect of dynamical spin accumulation is found to be greatly affected by the type of magnetic anisotropy exhibited by the molecule, and it develops for frequencies corresponding to the Kondo temperature. For the parallel magnetic configuration of the device, the presence of dynamical spin accumulation is conditioned by the interplay of ferromagnetic-lead-induced exchange field and the Kondo correlations.

New Evidence for Strategic Differences between Static and Dynamic Search Tasks: An Individual Observer Analysis of Eye Movements

PubMed Central

Dickinson, Christopher A.; Zelinsky, Gregory J.

2013-01-01

Two experiments are reported that further explore the processes underlying dynamic search. In Experiment 1, observers’ oculomotor behavior was monitored while they searched for a randomly oriented T among oriented L distractors under static and dynamic viewing conditions. Despite similar search slopes, eye movements were less frequent and more spatially constrained under dynamic viewing relative to static, with misses also increasing more with target eccentricity in the dynamic condition. These patterns suggest that dynamic search involves a form of sit-and-wait strategy in which search is restricted to a small group of items surrounding fixation. To evaluate this interpretation, we developed a computational model of a sit-and-wait process hypothesized to underlie dynamic search. In Experiment 2 we tested this model by varying fixation position in the display and found that display positions optimized for a sit-and-wait strategy resulted in higher d′ values relative to a less optimal location. We conclude that different strategies, and therefore underlying processes, are used to search static and dynamic displays. PMID:23372555

Dynamics of DNA methylomes underlie oyster development

PubMed Central

Sourdaine, Pascal; Guo, Ximing; Favrel, Pascal

2017-01-01

DNA methylation is a critical epigenetic regulator of development in mammals and social insects, but its significance in development outside these groups is not understood. Here we investigated the genome-wide dynamics of DNA methylation in a mollusc model, the oyster Crassostrea gigas, from the egg to the completion of organogenesis. Large-scale methylation maps reveal that the oyster genome displays a succession of methylated and non methylated regions, which persist throughout development. Differentially methylated regions (DMRs) are strongly regulated during cleavage and metamorphosis. The distribution and levels of methylated DNA within genomic features (exons, introns, promoters, repeats and transposons) show different developmental lansdscapes marked by a strong increase in the methylation of exons against introns after metamorphosis. Kinetics of methylation in gene-bodies correlate to their transcription regulation and to distinct functional gene clusters, and DMRs at cleavage and metamorphosis bear the genes functionally related to these steps, respectively. This study shows that DNA methylome dynamics underlie development through transcription regulation in the oyster, a lophotrochozoan species. To our knowledge, this is the first demonstration of such epigenetic regulation outside vertebrates and ecdysozoan models, bringing new insights into the evolution and the epigenetic regulation of developmental processes. PMID:28594821

Dynamics of DNA methylomes underlie oyster development.

PubMed

Riviere, Guillaume; He, Yan; Tecchio, Samuele; Crowell, Elizabeth; Gras, Michaël; Sourdaine, Pascal; Guo, Ximing; Favrel, Pascal

2017-06-01

DNA methylation is a critical epigenetic regulator of development in mammals and social insects, but its significance in development outside these groups is not understood. Here we investigated the genome-wide dynamics of DNA methylation in a mollusc model, the oyster Crassostrea gigas, from the egg to the completion of organogenesis. Large-scale methylation maps reveal that the oyster genome displays a succession of methylated and non methylated regions, which persist throughout development. Differentially methylated regions (DMRs) are strongly regulated during cleavage and metamorphosis. The distribution and levels of methylated DNA within genomic features (exons, introns, promoters, repeats and transposons) show different developmental lansdscapes marked by a strong increase in the methylation of exons against introns after metamorphosis. Kinetics of methylation in gene-bodies correlate to their transcription regulation and to distinct functional gene clusters, and DMRs at cleavage and metamorphosis bear the genes functionally related to these steps, respectively. This study shows that DNA methylome dynamics underlie development through transcription regulation in the oyster, a lophotrochozoan species. To our knowledge, this is the first demonstration of such epigenetic regulation outside vertebrates and ecdysozoan models, bringing new insights into the evolution and the epigenetic regulation of developmental processes.

Small, Short Duration Technical Team Dynamics

DTIC Science & Technology

2006-05-01

Organizations and a Strategy of Implementation. Academy of Management Journal. Vol. October, pp. 98-111. Ivancevich , John M. 1974. A Study of a Cognitive...Training Program: Trainer Styles and Group Development. Academy of Management Journal. Vol. 17, No. 3, p. 428. 315 Ivancevich , John M. and J...Vol. 90, pp. 141-153. Lyon , J. Michael. 2003. Mentoring of Scientists and Engineers: Dyadic and Formality Effects on Career Development and

Development of Feedforward Control in a Dynamic Manual Tracking Task

ERIC Educational Resources Information Center

van Roon, Dominique; Caeyenberghs, Karen; Swinnen, Stephan P.; Smits-Engelsman, Bouwien C. M.

2008-01-01

To examine the development of feedforward control during manual tracking, 117 participants in 5 age groups (6 to 7, 8 to 9, 10 to 11, 12 to 14, and 15 to 17 years) tracked an accelerating dot presented on a monitor by moving an electronic pen on a digitizer. To remain successful at higher target velocities, they had to create a predictive model of…

Guided Autobiography's Developmental Exchange: What's in It for Me?

ERIC Educational Resources Information Center

Thornton, James E.; Collins, John B.; Birren, James E.; Svensson, Cheryl

2011-01-01

The developmental exchange is a central feature of social development, interpersonal dynamics, situated learning, and personal transformation. It is the enabling process in Guided Autobiography (GAB) settings that promotes the achievement of personal goals and group accomplishments. Nevertheless, these exchanges are embedded in the GAB structures…

The Importance of Women's Literacy in Language Stabilization Projects.

ERIC Educational Resources Information Center

Gomez de Garcia, Jule; Olson, Maureen; Axelrod, Melissa

Experiences with indigenous people in Mexico and New Mexico illustrate that there are cultural and situational constraints on women's literacy. A participatory demonstration in linguistics in which the demonstrator is largely silent highlights the group dynamics of learning communities that develop in successful literacy and stabilization…

Multi-Purpose Crew Vehicle Camera Asset Planning: Imagery Previsualization

NASA Technical Reports Server (NTRS)

Beaulieu, K.

2014-01-01

Using JSC-developed and other industry-standard off-the-shelf 3D modeling, animation, and rendering software packages, the Image Science Analysis Group (ISAG) supports Orion Project imagery planning efforts through dynamic 3D simulation and realistic previsualization of ground-, vehicle-, and air-based camera output.

Reducing the risk of falls through proprioceptive dynamic posture training in osteoporotic women with kyphotic posturing: a randomized pilot study.

PubMed

Sinaki, Mehrsheed; Lynn, Susan G

2002-04-01

To assess the effect of a proprioceptive dynamic posture training program on balance in osteoporotic women with kyphotic posture. Subjects were randomly assigned to either a proprioceptive dynamic posture training program or exercise only group. Anthropometric measurements, muscle strength, level of physical activity, computerized dynamic posturography, and spine radiography were performed at baseline and 1 mo. At the 1-mo follow-up, three groups were formed on the basis of the baseline computerized dynamic posturography results. In general, groups 1 and 2 had no significant change at 1 mo, whereas group 3 improved balance significantly at 1 mo. The subjects who had abnormal balance and used the proprioceptive dynamic posture training program had the most significant improvement in balance. Improved balance could reduce the risk of falls.

Using enquiry in learning: from vision to reality in higher education.

PubMed

Horne, Maria; Woodhead, Kath; Morgan, Liz; Smithies, Lynda; Megson, Denise; Lyte, Geraldine

2007-02-01

This paper reports on the contribution of six nurse educators to embed enquiry-led learning in a pre-registration nursing programme. Their focus was to evaluate student and facilitator perspectives of a hybrid model of problem-based learning, a form of enquiry-based learning and to focus on facilitators' perceptions of its longer-term utility with large student groups. Problem-based learning is an established learning strategy in healthcare internationally; however, insufficient evidence of its effectiveness with large groups of pre-registration students exists. Fourth Generation Evaluation was used, applying the Nominal Group Technique and Focus Group interviews, for data collection. In total, four groups representing different branches of pre-registration students (n = 121) and 15 facilitators participated. Students identified seven strengths and six areas for development related to problem-based learning. Equally, analysis of facilitators' discussions revealed several themes related to strengths and challenges. The consensus was that using enquiry aided the development of independent learning and encouraged deeper exploration of nursing and allied subject material. However, problems and frustrations were identified in relation to large numbers of groups, group dynamics, room and library resources and personal development. The implications of these findings for longer-term utility with large student groups are discussed.

Chaos as a psychological construct: historical roots, principal findings, and current growth directions.

PubMed

Guastello, Stephen J

2009-07-01

The landmarks in the use of chaos and related constructs in psychology were entwined with the growing use of other nonlinear dynamical constructs, especially catastrophes and self-organization. The growth in substantive applications of chaos in psychology is partially related to the development of methodologies that work within the constraints of psychological data. The psychological literature includes rigorous theory with testable propositions, lighter-weight metaphorical uses of the construct, and colloquial uses of "chaos" with no particular theoretical intent. The current state of the chaos construct and supporting empirical research in psychological theory is summarized in neuroscience, psychophysics, psychomotor skill and other learning phenomena, clinical and abnormal psychology, and group dynamics and organizational behavior. Trends indicate that human systems do not remain chaotic indefinitely; they eventually self-organize, and the concept of the complex adaptive system has become prominent. Chaotic turbulence is generally higher in healthy systems compared to unhealthy systems, although opposite appears true in mood disorders. Group dynamics research shows trends consistent with the complex adaptive system, whereas organizational behavior lags behind in empirical studies relative to the quantity of its theory. Future directions for research involving the chaos construct and other nonlinear dynamics are outlined.

The development of phytosterol-lecithin mixed micelles and organogels.

PubMed

Matheson, Andrew B; Dalkas, Georgios; Gromov, Andrei; Euston, Stephen R; Clegg, Paul S

2017-12-13

We demonstrate that by mixing the phytosterol-ester oryzanol with lecithin in an organic solvent, both components may be dispersed at much higher concentrations than they may be individually. Dynamic light scattering and molecular dynamics simulations show that the mechanism for this is the formation of r ∼ 4 nm mixed micelles. Infrared spectroscopy and simulations suggest that these micelles are formed due in part to hydrogen bonding of the phosphate of the lecithin head-group, and the phenol group of the oryzanol. Rheology shows that by mixing these materials at an equimolar ratio, highly viscous suspensions are created. Furthermore, by adding water to these samples, a solid-like gel may be formed which offers mechanical properties close to those desired for a margarine type spread, whilst still solubilizing the oryzanol.

[The impact of dynamic platform exercises on knee joint muscle strength in patients with gonarthrosis treated with microfracture method].

PubMed

Klupiński, Kamil; Krochmalski, Jakub; Woldańska-Okońska, Marta

2017-06-23

Osteoarthritis is the most common joint disease. Gonarthrosis is one of the most serious diseases the highly developed modern medicine must face. The number of patients suffering from joint pain and progressive disability is growing, especially in economically developed countries. Over the years, the disease has been considered merely as a symptom of aging and the effect of "wear and tear" of the cartilage. At present it is known that the degenerative joint disease is of chronic and progressive nature and its pathogenesis is complex. The aim of the study was to determine the impact of dynamic platform exercises on knee joint muscle strength in patients with gonarthrosis treated with microfracture method. The study included 120 patients of both sexes, aged 40 to 65 years, height range1.60-1.90 m., weight 50- 100 kg. Patients were divided into two groups. Group I of 60 patients after knee arthroscopy (with performed microfractures on the articular cartilage) who were subjected to physiotherapy with the use of dynamometric platform and to isometric and dynamic exercises of muscles surrounding the knee joint. Group II (control) of 60 patients after knee arthroscopy (with performed microfractures on the articular cartilage), who were subjected only to isometric and dynamic exercises of muscles surrounding the knee joint. The patients underwent rehabilitation according to the same rehabilitation program suggested by the Medical Magnus Clinic in Lodz, which consisted in performing daily exercises in open and closed kinetic chains. All Group I and II patients were examined three times: before the start of the rehabilitation, after 4th week of rehabilitation (on the average 20 days of the procedures) and 3 months afterwards. The clinical examination included the measurement of muscle strength using Lovett test. It has been demonstrated that the introduction of modern highly specialized physiotherapy contributes to the improvement of the outcome and to the shortening of the treatment duration. A significant improvement was observed in all the examined patients at all stages of rehabilitation in relation to the baseline values. The conducted modern physiotherapy has a significant effect on the condition of patients after surgery. Different exercises on dynamometric platform combined with static and dynamic exercises exert a positive impact on the strengthening of muscles surrounding the knee joint, which in time perspective results in better quality of life of the patients.

Partnership in Psycho-Social Group Intervention for Cancer Patients: Factors to Creating Group Dynamics.

PubMed

Chujo, Masami; Okamura, Hitoshi

2015-03-01

The purpose of this study was to conduct a psycho-social group intervention consisting of 3 parts, educate patients on methods to cope with stress and solve problems, hold group discussions and practice progressive muscle relaxation (PMR) for cancer patients, and investigate the way that group dynamics work in psycho-social group interventions in Japan. Three facilitators and 2 sub-facilitators who conducted the group intervention for breast cancer patients were qualitatively and inductively analyzed using a phenomenological approach. As a result, "hard effort," "harmony of the whole group" and "collaboration between therapists" were extracted as the partnership functions of participants that work on the creation of group dynamics in psycho-social group interventions. There was a structure in which "harmony of the whole group" and "collaboration between therapists" coexisted based on the basic attitude of "hard effort." It was considered that these 3 intervention forms are involved in group dynamics in which participants can easily hold discussions, and are techniques necessary for group intervention contributing to changes in the psychological distress and the coping of participants.

Emergent patterns in interacting neuronal sub-populations

NASA Astrophysics Data System (ADS)

Kamal, Neeraj Kumar; Sinha, Sudeshna

2015-05-01

We investigate an ensemble of coupled model neurons, consisting of groups of varying sizes and intrinsic dynamics, ranging from periodic to chaotic, where the inter-group coupling interaction is effectively like a dynamic signal from a different sub-population. We observe that the minority group can significantly influence the majority group. For instance, when a small chaotic group is coupled to a large periodic group, the chaotic group de-synchronizes. However, counter-intuitively, when a small periodic group couples strongly to a large chaotic group, it leads to complete synchronization in the majority chaotic population, which also spikes at the frequency of the small periodic group. It then appears that the small group of periodic neurons can act like a pacemaker for the whole network. Further, we report the existence of varied clustering patterns, ranging from sets of synchronized clusters to anti-phase clusters, governed by the interplay of the relative sizes and dynamics of the sub-populations. So these results have relevance in understanding how a group can influence the synchrony of another group of dynamically different elements, reminiscent of event-related synchronization/de-synchronization in complex networks.

The delta cooperative model: a dynamic and innovative team-work activity to develop research skills in microbiology.

PubMed

Rios-Velazquez, Carlos; Robles-Suarez, Reynaldo; Gonzalez-Negron, Alberto J; Baez-Santos, Ivan

2006-05-01

The Delta Cooperative Model (DCM) is a dynamic and innovative teamwork design created to develop fundamentals in research skills. High school students in the DCM belong to the Upward Bound Science and Math (UBSM) program at the Inter American University, Ponce Campus. After workshops on using the scientific method, students were organized into groups of three students with similar research interests. Each student had to take on a role within the group as either a researcher, data analyst, or research editor. Initially, each research team developed hypothesis-driven ideas on their proposed project. In intrateam research meetings, they emphasized team-specific tasks. Next, interteam meetings were held to present ideas and receive critical input. Finally, oral and poster research presentations were conducted at the UBSM science fair. Several team research projects covered topics in medical, environmental, and general microbiology. The three major assessment areas for the workshop and DCM included: (i) student's perception of the workshops' effectiveness in developing skills, content, and values; (ii) research team self- and group participation evaluation, and (iii) oral and poster presentation during the science fair. More than 91% of the students considered the workshops effective in the presentation of scientific method fundamentals. The combination of the workshop and the DCM increased student's knowledge by 55% from pre- to posttests. Two rubrics were designed to assess the oral presentation and poster set-up. The poster and oral presentation scores averaged 83% and 75% respectively. Finally, we present a team assessment instrument that allows the self- and group evaluation of each research team. While the DCM has educational plasticity and versatility, here we document how the this model has been successfully incorporated in training and engaging students in scientific research in microbiology.

Facilitating Dental Student Reflections: Using Mentor Groups to Discuss Clinical Experiences and Personal Development.

PubMed

Koole, Sebastiaan; Christiaens, Veronique; Cosyn, Jan; De Bruyn, Hugo

2016-10-01

Despite the consensus on the importance of reflection for dental professionals, a lack of understanding remains about how students and clinicians should develop their ability to reflect. The aim of this study was to investigate dental students' and mentors' perceptions of mentor groups as an instructional method to facilitate students' reflection in terms of the strategy's learning potential, role of the mentor, group dynamics, and feasibility. At Ghent University in Belgium, third- and fourth-year dental students were encouraged to reflect on their clinical experiences and personal development in three reflective mentor sessions. No preparation or reports afterwards were required; students needed only to participate in the sessions. Sessions were guided by trained mentors to establish a safe environment, frame clinical discussions, and stimulate reflection. Students' and mentors' perceptions of the experience were assessed with a 17-statement questionnaire with response options on a five-point Likert scale (1=totally disagree to 5=totally agree). A total of 50 students and eight mentors completed the questionnaire (response rates 81% and 89%, respectively). Both students and mentors had neutral to positive perceptions concerning the learning potential, role of the mentor, group dynamics, and feasibility. The mean ideal total time for sessions in a year was 99 minutes (third-year students), 111 minutes (fourth-year students), and 147 minutes (mentors). Reported reflective topics related to patient management, frustrations, and practice of dentistry. Overall mean appreciation for the experience ranged from 14.50 to 15.14 on the 20-point scale. These findings about students' and mentors' positive perceptions of the experience suggest that mentor groups may be a potentially valuable strategy to promote dental students' reflection.

Dynamic Balance Deficits 6 Months Following First-Time Acute Lateral Ankle Sprain: A Laboratory Analysis.

PubMed

Doherty, Cailbhe; Bleakley, Chris; Hertel, Jay; Caulfield, Brian; Ryan, John; Delahunt, Eamonn

2015-08-01

Controlled laboratory study. To utilize kinematic and stabilometric measures to compare dynamic balance during performance of the Star Excursion Balance Test between persons 6 months following first-time lateral ankle sprain (LAS) and a noninjured control group. Biomechanical evaluation of dynamic balance in persons following first-time LAS during performance of the Star Excursion Balance Test could provide insight into the mechanisms by which individuals proceed to recover fully or develop chronic ankle instability. Sagittal plane kinematics of the lower extremity and the center-of-pressure path during the performance of the anterior, posterolateral, and posteromedial reach directions of the Star Excursion Balance Test were obtained from 69 participants 6 months following first-time acute LAS and from a control group of 20 noninjured participants. Compared to the control group, the LAS group displayed lower normalized reach distances in all 3 reach directions on the injured and noninjured limbs, with the largest observed effect size in the posterolateral direction (P = .001, ηp(2) = 0.07). The performance impairment was associated with less hip and knee flexion and ankle dorsiflexion at the point of maximum reach (P<.02), and coincided with less complexity of the center-of-pressure path (P<.05). Participants with a 6-month history of LAS exhibit a persistence of deficits previously established in the acute phase of injury.

The creative potential of play and regression in analytical training: a personal reflection.

PubMed

Addenbrooke, M

1997-07-01

The seminar group can serve as a framework in which to meet the fear generated during training. The group can become a maddening environment, but on occasions when it is experienced by the trainee as good enough, it can act like a playgroup which facilitates development. Experiences in the group can be viewed from the perspectives of group dynamics or of transference phenomena which embody regression. When this regression enables scope for play it can serve in the interests of ego development in the process of discovering the sort of analyst the trainee is becoming as the training unfolds. During play aspects of oneself can merge, then differentiate again. They can have different meanings at the same time. The rational and emotional, the adult and the childlike are all given a place in play.

Linking body mass and group dynamics in an obligate cooperative breeder.

PubMed

Ozgul, Arpat; Bateman, Andrew W; English, Sinead; Coulson, Tim; Clutton-Brock, Tim H

2014-11-01

Social and environmental factors influence key life-history processes and population dynamics by affecting fitness-related phenotypic traits such as body mass. The role of body mass is particularly pronounced in cooperative breeders due to variation in social status and consequent variation in access to resources. Investigating the mechanisms underlying variation in body mass and its demographic consequences can help elucidate how social and environmental factors affect the dynamics of cooperatively breeding populations. In this study, we present an analysis of the effect of individual variation in body mass on the temporal dynamics of group size and structure of a cooperatively breeding mongoose, the Kalahari meerkat, Suricata suricatta. First, we investigate how body mass interacts with social (dominance status and number of helpers) and environmental (rainfall and season) factors to influence key life-history processes (survival, growth, emigration and reproduction) in female meerkats. Next, using an individual-based population model, we show that the models explicitly including individual variation in body mass predict group dynamics better than those ignoring this morphological trait. Body mass influences group dynamics mainly through its effects on helper emigration and dominant reproduction. Rainfall has a trait-mediated, destabilizing effect on group dynamics, whereas the number of helpers has a direct and stabilizing effect. Counteracting effects of number of helpers on different demographic rates, despite generating temporal fluctuations, stabilizes group dynamics in the long term. Our study demonstrates that social and environmental factors interact to produce individual variation in body mass and accounting for this variation helps to explain group dynamics in this cooperatively breeding population. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

Dynamic Locked Plating of Distal Femur Fractures.

PubMed

Linn, Michael S; McAndrew, Christopher M; Prusaczyk, Beth; Brimmo, Olubusola; Ricci, William M; Gardner, Michael J

2015-10-01

Nonunion after locked bridge plating of comminuted distal femur fractures is not uncommon. "Dynamic" locked plating may create an improved mechanical environment, thereby achieving higher union rates than standard locked plating constructs. Academic Level 1 Trauma Center. Twenty-eight patients with comminuted supracondylar femur fractures treated with either dynamic or standard locked plating. Dynamic plating was achieved using an overdrilling technique of the near cortex to allow for a 0.5-mm "halo" around the screw shaft at the near cortex. Standard locked plating was done based on manufacturer's suggested technique. The patients treated with dynamic plating were matched 1:1 with those treated with standard locked plating based on OTA classification and working length. Three blinded observers made callus measurements on 6-week radiographs using a 4-point ordinal scale. The results were analyzed using a 2-tailed t test and 2-way intraclass correlations. The dynamic plating group had significantly greater callus (2.0; SD, 0.7) compared with the control group (1.3: SD, 0.8, P = 0.048) with substantial agreement amongst observers in both consistency (0.724) and absolute score (0.734). With dynamic plating group, 1 patient failed to unite, versus three in the control group (P = 0.59). The dynamic group had a mean change in coronal plane alignment of 0.5 degrees (SD, 2.6) compared with 0.6 (SD, 3.0) for the control group (P = 0.9) without fixation failure in either group. Overdrilling the near cortex in metaphyseal bridge plating can be adapted to standard implants to create a dynamic construct and increase axial motion. This technique seems to be safe and leads to increased callus formation, which may decrease nonunion rates seen with standard locked plating. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Technical Review of the CENWP Computational Fluid Dynamics Model of the John Day Dam Forebay

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

Rakowski, Cynthia L.; Serkowski, John A.; Richmond, Marshall C.

The US Army Corps of Engineers Portland District (CENWP) has developed a computational fluid dynamics (CFD) model of the John Day forebay on the Columbia River to aid in the development and design of alternatives to improve juvenile salmon passage at the John Day Project. At the request of CENWP, Pacific Northwest National Laboratory (PNNL) Hydrology Group has conducted a technical review of CENWP's CFD model run in CFD solver software, STAR-CD. PNNL has extensive experience developing and applying 3D CFD models run in STAR-CD for Columbia River hydroelectric projects. The John Day forebay model developed by CENWP is adequatelymore » configured and validated. The model is ready for use simulating forebay hydraulics for structural and operational alternatives. The approach and method are sound, however CENWP has identified some improvements that need to be made for future models and for modifications to this existing model.« less

Exploring dynamics of abusive lesbian relationships: preliminary analysis of a multisite, qualitative study.

PubMed

Ristock, Janice L

2003-06-01

This paper presents preliminary results from a multisite, qualitative study on violence in lesbian relationships. A framework for conducting community-based, empowerment research that draws on theories of community psychology, feminism, and postmodernism is presented. The study was designed to understand the dynamics of abusive lesbian relationships and social service providers' responses to the abuse. Results from 80 in-depth interviews with lesbians who have experienced relationship violence are examined with a particular focus on a pattern of first relationships being abusive and a theme of shifting power dynamics. Analysis of focus group discussions with 45 feminist service providers (e.g., counselors, shelter workers, social workers, healthcare providers) reveals the difficulties in assessing the power dynamics of abusive same-sex relationships and in developing appropriate responses when relying on heterosexually gendered models developed to address men's violence against women. The preliminary results present implications both for how we theorize and research this form of violence, and for improving the practices and policies of social services that work with lesbian, gay, bisexual, and transgendered communities.

Developing a Theory for Dynamic Campaign Planning,

DTIC Science & Technology

1988-04-26

the future commander, or, more accurately, to guide him in his self education, not to accompany him to the battlefield." 4 Theory can then serve as an...the ship. These improvements drastically improved the support groups resposiveness and lethality and helped turn the tide against the U-boats. 7

Development of Innovative Group Work Practice Using the Intervention Research Paradigm

ERIC Educational Resources Information Center

Comer, Edna; Meier, Andrea; Galinsky, Maeda J.

2004-01-01

Rothman and Thomas' intervention research (IR) paradigm provides an alternative, developmental research method that is appropriate for practice research, especially at the early stages. It is more flexible than conventional experimental designs, capitalizes on the availability of small samples, accommodates the dynamism and variation in practice…

Outcome Research on Short-Term Psychodynamic Psychotherapy: A Preliminary Review.

ERIC Educational Resources Information Center

White, Scott Allyn

This paper reviews the empirical research on short-term psychodynamic psychotherapy (STDP). It begins with a brief history of STDP, identifying current developers and researchers of STDP and listing commonalities among various short-term dynamic psychotherapies. In this review, research is grouped broadly into two categories: controlled…

The Educational and Professional Trajectories of Working Young People

ERIC Educational Resources Information Center

Cherednichenko, G. A.

2012-01-01

The dynamism of social processes, the development of technologies, and the modernization of industrial production require raising the education and qualifications of blue-collar workers, particularly working young people. This accounts for the focus on problems of that group's formation, their integration into society, their acquisition and…

Working with Emotions in Community Organizations.

ERIC Educational Resources Information Center

Hoggett, Paul; Miller, Chris

2000-01-01

The emotional life of community organizations and their members has been neglected in community development, although it can have an impact at individual, societal, and micro-social levels. Both the instrumental tasks and the emotions of organizations must be addressed. Understanding group dynamics can create awareness of this dimension. (Contains…

Developing Dynamic Reference Models and a Decision Support Framework for Southeastern Ecosystems: An Integrated Approach

DTIC Science & Technology

2015-06-01

Tuesday afternoon, March 25, and the solution breakout group discussions took place on Wednesday morning, March 26. Each breakout group presented...UK. Creech, M. N., L. K. Kirkman, and L. A. Morris . 2012. Alteration and recovery of slash pile burn sites in the restoration of a fire...Lesica, W. Morris , G. Oostermeijer, P. Quintana-Ascencio, A. Stanely, T. Ticktin, R. Valverde, and J. Williams. 2011. How do plant ecologists use matric

Muscle Contractile Properties in Severely Burned Rats

PubMed Central

Wu, Xiaowu; Wolf, Steven E.; Walters, Thomas J.

2010-01-01

Burn induces a sustained catabolic response which causes massive loss of muscle mass after injury. A better understanding of the dynamics of muscle wasting and its impact on muscle function is necessary for the development of effective treatments. Male Sprague-Dawley rats underwent either a 40% total body surface area (TBSA) scald burn or sham burn, and were further assigned to subgroups at four time points after injury (days 3, 7, 14 and 21). In situ isometric contractile properties were measured including twitch tension (Pt), tetanic tension (Po) and fatigue properties. Body weight decreased in burn and sham groups through day 3, however, body weight in the sham groups recovered and increased over time compared to burned groups, which progressively decreased until day 21 after injury. Significant differences in muscle wet weight and protein weight were found between sham and burn. Significant differences in muscle contractile properties were found at day 14 with lower absolute Po as well as specific Po in burned rats compared to sham. After burn, the muscle twitch tension was significantly higher than the sham at day 21. No significant difference in fatigue properties was found between the groups. This study demonstrates dynamics of muscle atrophy and muscle contractile properties after severe burn; this understanding will aid in the development of approaches designed to reduce the rate and extent of burn induced muscle loss and function. PMID:20381255

Time Reparametrization Group and the Long Time Behavior in Quantum Glassy Systems

NASA Astrophysics Data System (ADS)

Kennett, Malcolm P.; Chamon, Claudio

2001-02-01

We study the long time dynamics of a quantum version of the Sherrington-Kirkpatrick model. Time reparametrizations of the dynamical equations have a parallel with renormalization group transformations; in this language the long time behavior of this model is controlled by a reparametrization group ( RpG) fixed point of the classical dynamics. The irrelevance of quantum terms in the dynamical equations in the aging regime explains the classical nature of the out of equilibrium fluctuation-dissipation relation.

Group Dynamics as a Critical Component of Successful Space Exploration: Conceptual Theory and Insights from the Biosphere 2 Closure Experiment

NASA Astrophysics Data System (ADS)

Nelson, Mark; Allen, John P.

As space exploration and eventually habitation achieves longer durations, successfully managing group dynamics of small, physically isolated groups will become vital. The paper summarizes important underlying research and conceptual theory and how these manifested in a well-documented example: the closure experiments of Biosphere 2. Key research breakthroughs in discerning the operation of small human groups comes from the pioneering work of W.R. Bion. He discovered two competing modalities of behavior. The first is the “task-oriented” or work group governed by shared acceptance of goals, reality-thinking in relation to time, resources and rational, and intelligent management of challenges presented. The opposing, usually unconscious, modality is what Bion called the “basic-assumption” group and alternates between three “group animal” groups: dependency/kill the leader; fight/flight and pairing. If not dealt with, these dynamics work to undermine and defeat the conscious task group’s goal achievement. The paper discusses crew training and selection, various approaches to structuring the work and hierarchy of the group, the importance of contact with a larger population through electronic communication and dealing with the “us-them” syndrome frequently observed between crew and Mission Control. The experience of the first two year closure of Biosphere 2 is drawn on in new ways to illustrate vicissitudes and management of group dynamics especially as both the inside team of biospherians and key members of Mission Control had training in working with group dynamics. Insights from that experience may help mission planning so that future groups in space cope successfully with inherent group dynamics challenges that arise.

The Dynamics of Group Formation Among Leeches

PubMed Central

Bisson, Giacomo; Bianconi, Ginestra; Torre, Vincent

2012-01-01

Leeches exploring a new environment continuously meet each other and merge in temporary groups. After 2–3 h, leeches become attracted to each other eventually forming a large and stable group. When their number is reduced, leeches remain solitary, behaving independently. Group formation is facilitated by body injection of serotonin (5-HT) and the level of endogenous 5-HT is elevated in leeches forming a large group. In contrast, intravenous injection of 5-HT antagonists prevented injected leeches from joining a large group of conspecifics. When sensilla near the head were ablated or the supraesophageal ganglion disconnected, leeches remained solitary, but explored the environment swimming and crawling. These results suggest that group formation is initiated by a release of 5-HT triggered by sensilla stimulation and its dynamics can be explained by the establishment of a reinforcement dynamics, as observed during human group formation. As 5-HT affects social interactions also in humans, group formation in leeches and humans share a similar dynamics and hormonal control. PMID:22629247

Group Dynamic Processes in Email Groups

ERIC Educational Resources Information Center

Alpay, Esat

2005-01-01

Discussion is given on the relevance of group dynamic processes in promoting decision-making in email discussion groups. General theories on social facilitation and social loafing are considered in the context of email groups, as well as the applicability of psychodynamic and interaction-based models. It is argued that such theories may indeed…

Charting Multidisciplinary Team External Dynamics Using a Systems Thinking Approach

NASA Technical Reports Server (NTRS)

Barthelemy, Jean-Francois; Waszak, Martin R.; Jones, Kenneth M.; Silcox, Richard J.; Silva, Walter A.; Nowaczyk, Ronald H.

1998-01-01

Using the formalism provided by the Systems Thinking approach, the dynamics present when operating multidisciplinary teams are examined in the context of the NASA Langley Research and Technology Group, an R&D organization organized along functional lines. The paper focuses on external dynamics and examines how an organization creates and nurtures the teams and how it disseminates and retains the lessons and expertise created by the multidisciplinary activities. Key variables are selected and the causal relationships between the variables are identified. Five "stories" are told, each of which touches on a different aspect of the dynamics. The Systems Thinking Approach provides recommendations as to interventions that will facilitate the introduction of multidisciplinary teams and that therefore will increase the likelihood of performing successful multidisciplinary developments. These interventions can be carried out either by individual researchers, line management or program management.

The Amber Biomolecular Simulation Programs

PubMed Central

CASE, DAVID A.; CHEATHAM, THOMAS E.; DARDEN, TOM; GOHLKE, HOLGER; LUO, RAY; MERZ, KENNETH M.; ONUFRIEV, ALEXEY; SIMMERLING, CARLOS; WANG, BING; WOODS, ROBERT J.

2006-01-01

We describe the development, current features, and some directions for future development of the Amber package of computer programs. This package evolved from a program that was constructed in the late 1970s to do Assisted Model Building with Energy Refinement, and now contains a group of programs embodying a number of powerful tools of modern computational chemistry, focused on molecular dynamics and free energy calculations of proteins, nucleic acids, and carbohydrates. PMID:16200636

Quantification of myocardial blood flow using dynamic 320-row multi-detector CT as compared with ¹⁵O-H₂O PET.

PubMed

Kikuchi, Yasuka; Oyama-Manabe, Noriko; Naya, Masanao; Manabe, Osamu; Tomiyama, Yuuki; Sasaki, Tsukasa; Katoh, Chietsugu; Kudo, Kohsuke; Tamaki, Nagara; Shirato, Hiroki

2014-07-01

This study introduces a method to calculate myocardium blood flow (MBF) and coronary flow reserve (CFR) using the relatively low-dose dynamic 320-row multi-detector computed tomography (MDCT), validates the method against (15)O-H₂O positron-emission tomography (PET) and assesses the CFRs of coronary artery disease (CAD) patients. Thirty-two subjects underwent both dynamic CT perfusion (CTP) and PET perfusion imaging at rest and during pharmacological stress. In 12 normal subjects (pilot group), the calculation method for MBF and CFR was established. In the other 13 normal subjects (validation group), MBF and CFR obtained by dynamic CTP and PET were compared. Finally, the CFRs obtained by dynamic CTP and PET were compared between the validation group and CAD patients (n = 7). Correlation between MBF of MDCT and PET was strong (r = 0.95, P < 0.0001). CFR showed good correlation between dynamic CTP and PET (r = 0.67, P = 0.0126). CFRCT in the CAD group (2.3 ± 0.8) was significantly lower than that in the validation group (5.2 ± 1.8) (P = 0.0011). We established a method for measuring MBF and CFR with the relatively low-dose dynamic MDCT. Lower CFR was well demonstrated in CAD patients by dynamic CTP. • MBF and CFR can be calculated using dynamic CTP with 320-row MDCT. • MBF and CFR showed good correlation between dynamic CTP and PET. • Lower CFR was well demonstrated in CAD patients by dynamic CTP.

Development of dynamic Bayesian models for web application test management

NASA Astrophysics Data System (ADS)

Azarnova, T. V.; Polukhin, P. V.; Bondarenko, Yu V.; Kashirina, I. L.

2018-03-01

The mathematical apparatus of dynamic Bayesian networks is an effective and technically proven tool that can be used to model complex stochastic dynamic processes. According to the results of the research, mathematical models and methods of dynamic Bayesian networks provide a high coverage of stochastic tasks associated with error testing in multiuser software products operated in a dynamically changing environment. Formalized representation of the discrete test process as a dynamic Bayesian model allows us to organize the logical connection between individual test assets for multiple time slices. This approach gives an opportunity to present testing as a discrete process with set structural components responsible for the generation of test assets. Dynamic Bayesian network-based models allow us to combine in one management area individual units and testing components with different functionalities and a direct influence on each other in the process of comprehensive testing of various groups of computer bugs. The application of the proposed models provides an opportunity to use a consistent approach to formalize test principles and procedures, methods used to treat situational error signs, and methods used to produce analytical conclusions based on test results.

Empirical study on social groups in pedestrian evacuation dynamics

NASA Astrophysics Data System (ADS)

von Krüchten, Cornelia; Schadschneider, Andreas

2017-06-01

Pedestrian crowds often include social groups, i.e. pedestrians that walk together because of social relationships. They show characteristic configurations and influence the dynamics of the entire crowd. In order to investigate the impact of social groups on evacuations we performed an empirical study with pupils. Several evacuation runs with groups of different sizes and different interactions were performed. New group parameters are introduced which allow to describe the dynamics of the groups and the configuration of the group members quantitatively. The analysis shows a possible decrease of evacuation times for large groups due to self-ordering effects. Social groups can be approximated as ellipses that orientate along their direction of motion. Furthermore, explicitly cooperative behaviour among group members leads to a stronger aggregation of group members and an intermittent way of evacuation.

The guided autobiography method: a learning experience.

PubMed

Thornton, James E

2008-01-01

This article discusses the proposition that learning is an unexplored feature of the guided autobiography method and its developmental exchange. Learning, conceptualized and explored as the embedded and embodied processes, is essential in narrative activities of the guided autobiography method leading to psychosocial development and growth in dynamic, temporary social groups. The article is organized in four sections and summary. The first section provides a brief overview of the guided autobiography method describing the interplay of learning and experiencing in temporary social groups. The second section offers a limited review on learning and experiencing as processes that are essential for development, growth, and change. The third section reviews the small group activities and the emergence of the "developmental exchange" in the guided autobiography method. Two theoretical constructs provide a conceptual foundation for the developmental exchange: a counterpart theory of aging as development and collaborative-situated group learning theory. The summary recaps the main ideas and issues that shape the guided autobiography method as learning and social experience using the theme, "Where to go from here."

Study of the Dynamics of Transcephalic Cerebral Impedance Data during Cardio-Vascular Surgery

NASA Astrophysics Data System (ADS)

Atefi, S. R.; Seoane, F.; Lindecrantz, K.

2013-04-01

Postoperative neurological deficits are one of the risks associated with cardio vascular surgery, necessitating development of new techniques for cerebral monitoring. In this study an experimental observation regarding the dynamics of transcephalic Electrical Bioimpedance (EBI) in patients undergoing cardiac surgery with and without extracorporeal circulation (ECC) was conducted to investigate the potential use of electrical Bioimpedance for cerebral monitoring in cardio vascular surgery. Tetrapolar transcephalic EBI measurements at single frequency of 50 kHz were recorded prior to and during cardio vascular surgery. The obtained results show that the transcephalic impedance decreases in both groups of patients as operation starts, however slight differences in these two groups were also observed with the cerebral impedance reduction in patients having no ECC being less common and not as pronounced as in the ECC group. Changes in the cerebral impedance were in agreement with changes of haematocrit and temperature. The origin of EBI changes is still unexplained however these results encourage us to continue investigating the application of electrical bioimpedance cerebral monitoring clinically.

Preliminary report on small group factors in long duration space flights: Review and directions for future research

NASA Technical Reports Server (NTRS)

Harrison, A. A.

1979-01-01

Group dynamics, sociological and psychological factors are examined. Crew composition and compatability are studied. Group dynamics analysis includes: leadership; cohesiveness; conformity; and conflict.

Access Control for Cooperation Systems Based on Group Situation

NASA Astrophysics Data System (ADS)

Kim, Minsoo; Joshi, James B. D.; Kim, Minkoo

Cooperation systems characterize many emerging environments such as ubiquitous and pervasive systems. Agent based cooperation systems have been proposed in the literature to address challenges of such emerging application environments. A key aspect of such agent based cooperation system is the group situation that changes dynamically and governs the requirements of the cooperation. While individual agent context is important, the overall cooperation behavior is more driven by the group context because of relationships and interactions between agents. Dynamic access control based on group situation is a crucial challenge in such cooperation systems. In this paper we propose a dynamic role based access control model for cooperation systems based on group situation. The model emphasizes capability based agent to role mapping and group situation based permission assignment to allow capturing dynamic access policies that evolve continuously.

Emerging Applications of Polymersomes in Delivery: from Molecular Dynamics to Shrinkage of Tumors

PubMed Central

Discher, Dennis E.; Ortiz, Vanessa; Srinivas, Goundla; Klein, Michael L.; Kim, Younghoon; Christian, David; Cai, Shenshen; Photos, Peter; Ahmed, Fariyal

2014-01-01

Polymersomes are self-assembled shells of amphiphilic block copolymers that are currently being developed by many groups for fundamental insights into the nature of self-assembled states as well as for a variety of potential applications. While recent reviews have highlighted distinctive properties – particularly stability – that are strongly influenced by both copolymer type and polymer molecular weight, here we first review some of the more recent developments in computational molecular dynamics (MD) schemes that lend insight into assembly. We then review polymersome loading, in vivo stealthiness, degradation-based disassembly for controlled release, and even tumor-shrinkage in vivo. Comparisons of polymersomes with viral capsids are shown to encompass and inspire many aspects of current designs. PMID:24692840

Designing an Agent-Based Model Using Group Model Building: Application to Food Insecurity Patterns in a U.S. Midwestern Metropolitan City.

PubMed

Koh, Keumseok; Reno, Rebecca; Hyder, Ayaz

2018-04-01

Recent advances in computing resources have increased interest in systems modeling and population health. While group model building (GMB) has been effectively applied in developing system dynamics models (SD), few studies have used GMB for developing an agent-based model (ABM). This article explores the use of a GMB approach to develop an ABM focused on food insecurity. In our GMB workshops, we modified a set of the standard GMB scripts to develop and validate an ABM in collaboration with local experts and stakeholders. Based on this experience, we learned that GMB is a useful collaborative modeling platform for modelers and community experts to address local population health issues. We also provide suggestions for increasing the use of the GMB approach to develop rigorous, useful, and validated ABMs.

Scaling behavior of online human activity

NASA Astrophysics Data System (ADS)

Zhao, Zhi-Dan; Cai, Shi-Min; Huang, Junming; Fu, Yan; Zhou, Tao

2012-11-01

The rapid development of the Internet technology enables humans to explore the web and record the traces of online activities. From the analysis of these large-scale data sets (i.e., traces), we can get insights about the dynamic behavior of human activity. In this letter, the scaling behavior and complexity of human activity in the e-commerce, such as music, books, and movies rating, are comprehensively investigated by using the detrended fluctuation analysis technique and the multiscale entropy method. Firstly, the interevent time series of rating behaviors of these three types of media show similar scaling properties with exponents ranging from 0.53 to 0.58, which implies that the collective behaviors of rating media follow a process embodying self-similarity and long-range correlation. Meanwhile, by dividing the users into three groups based on their activities (i.e., rating per unit time), we find that the scaling exponents of the interevent time series in the three groups are different. Hence, these results suggest that a stronger long-range correlations exist in these collective behaviors. Furthermore, their information complexities vary in the three groups. To explain the differences of the collective behaviors restricted to the three groups, we study the dynamic behavior of human activity at the individual level, and find that the dynamic behaviors of a few users have extremely small scaling exponents associated with long-range anticorrelations. By comparing the interevent time distributions of four representative users, we can find that the bimodal distributions may bring forth the extraordinary scaling behaviors. These results of the analysis of the online human activity in the e-commerce may not only provide insight into its dynamic behaviors but may also be applied to acquire potential economic interest.

Banding of NMR-derived Methyl Order Parameters: Implications for Protein Dynamics

PubMed Central

Sharp, Kim A.; Kasinath, Vignesh; Wand, A. Joshua

2014-01-01

Our understanding of protein folding, stability and function has begun to more explicitly incorporate dynamical aspects. Nuclear magnetic resonance has emerged as a powerful experimental method for obtaining comprehensive site-resolved insight into protein motion. It has been observed that methyl-group motion tends to cluster into three “classes” when expressed in terms of the popular Lipari-Szabo model-free squared generalized order parameter. Here the origins of the three classes or bands in the distribution of order parameters are examined. As a first step, a Bayesian based approach, which makes no a priori assumption about the existence or number of bands, is developed to detect the banding of O2axis values derived either from NMR experiments or molecular dynamics simulations. The analysis is applied to seven proteins with extensive molecular dynamics simulations of these proteins in explicit water to examine the relationship between O2 and fine details of the motion of methyl bearing side chains. All of the proteins studied display banding, with some subtle differences. We propose a very simple yet plausible physical mechanism for banding. Finally, our Bayesian method is used to analyze the measured distributions of methyl group motions in the catabolite activating protein and several of its mutants in various liganded states and discuss the functional implications of the observed banding to protein dynamics and function. PMID:24677353

Influence of visual control, conduction, and central integration on static and dynamic balance in healthy older adults.

PubMed

Perrin, P P; Jeandel, C; Perrin, C A; Béné, M C

1997-01-01

Aging is associated with decreased balance abilities, resulting in an increased risk of fall. In order to appreciate the visual, somatosensory, and central signals involved in balance control, sophisticated methods of posturography assessment have been developed, using static and dynamic tests, eventually associated with electromyographic measurements. We applied such methods to a population of healthy older adults in order to appreciate the respective importance of each of these sensorial inputs in aging individuals. Posture control parameters were recorded on a force-measuring platform in 41 healthy young (age 28.5 +/- 5.9 years) and 50 older (age 69.8 +/- 5.9 years) adults, using a static test and two dynamic tests performed by all individuals first with eyes open, then with eyes closed. The distance covered by the center of foot pressure, sway area, and anteroposterior oscillations were significantly higher, with eyes open or closed, in older people than in young subjects. Significant differences were noted in dynamic tests with longer latency responses in the group of old people. Dynamic recordings in a sinusoidal test had a more regular pattern when performed eyes open in both groups and evidenced significantly greater instability in old people. These data suggest that vision remains important in maintaining postural control while conduction and central integration become less efficient with age.

Interaction dynamics: The case of the water sector skills plan in South Africa.

PubMed

Moyo, Laurane; Wehn, Uta

2017-02-01

Despite extensive and continuous efforts to strengthen the capacity of people, organizations and institutions, there is evidence of an increasing gap between the existing and required capacities within the water sector. Consensus seems to be emerging regarding the need for national strategies to improve water sector capacity development. This paper analyses the dynamics of actors' interactions and their characteristics (motivation, cognition and power) during the formulation and implementation of a specific capacity development strategy, namely the Water Sector Skills Plan (SSP) in South Africa. Based on the Contextual Interactive Theory and empirical findings, our analysis indicates slow progression and challenges with implementing the SSP, mainly due to the lack of consultation with key stakeholders during the formulation stage, a lack of data sharing among the target group (the Sector Education Training Authorities), and a lack of capacities within the key implementing organizations. These policy dynamics need to be taken into account when advocating for national capacity development strategies as a solution for challenges with water sector capacity development. The paper proposes the recommendations that are of relevance for the SSP as well as similar initiatives in other countries. Copyright © 2016. Published by Elsevier Ltd.

A comparison of head dynamic response and brain tissue stress and strain using accident reconstructions for concussion, concussion with persistent postconcussive symptoms, and subdural hematoma.

PubMed

Oeur, R Anna; Karton, Clara; Post, Andrew; Rousseau, Philippe; Hoshizaki, T Blaine; Marshall, Shawn; Brien, Susan E; Smith, Aynsley; Cusimano, Michael D; Gilchrist, Michael D

2015-08-01

Concussions typically resolve within several days, but in a few cases the symptoms last for a month or longer and are termed persistent postconcussive symptoms (PPCS). These persisting symptoms may also be associated with more serious brain trauma similar to subdural hematoma (SDH). The objective of this study was to investigate the head dynamic and brain tissue responses of injury reconstructions resulting in concussion, PPCS, and SDH. Reconstruction cases were obtained from sports medicine clinics and hospitals. All subjects received a direct blow to the head resulting in symptoms. Those symptoms that resolved in 9 days or fewer were defined as concussions (n = 3). Those with symptoms lasting longer than 18 months were defined as PPCS (n = 3), and 3 patients presented with SDHs (n = 3). A Hybrid III headform was used in reconstruction to obtain linear and rotational accelerations of the head. These dynamic response data were then input into the University College Dublin Brain Trauma Model to calculate maximum principal strain and von Mises stress. A Kruskal-Wallis test followed by Tukey post hoc tests were used to compare head dynamic and brain tissue responses between injury groups. Statistical significance was set at p < 0.05. A significant difference was identified for peak resultant linear and rotational acceleration between injury groups. Post hoc analyses revealed the SDH group had higher linear and rotational acceleration responses (316 g and 23,181 rad/sec(2), respectively) than the concussion group (149 g and 8111 rad/sec(2), respectively; p < 0.05). No significant differences were found between groups for either brain tissue measures of maximum principal strain or von Mises stress. The reconstruction of accidents resulting in a concussion with transient symptoms (low severity) and SDHs revealed a positive relationship between an increase in head dynamic response and the risk for more serious brain injury. This type of relationship was not found for brain tissue stress and strain results derived by finite element analysis. Future research should be undertaken using a larger sample size to confirm these initial findings. Understanding the relationship between the head dynamic and brain tissue response and the nature of the injury provides important information for developing strategies for injury prevention.

The effects of computer-based dynamic visualization simulations on student learning in high school science

NASA Astrophysics Data System (ADS)

Moodley, Sadha

The purpose of this study was to determine whether the use of dynamic computer-based visualizations of the classical model of particle behavior helps to improve student understanding, performance, and interest in science when used by teachers as visual presentations to complement their traditional methods of teaching. The software, Virtual Molecular Dynamics Laboratory (VMDL), was developed at the Center for Polymer Studies at Boston University through funding from the National Science Foundation. The design of the study included five pairs of classes in four different schools in New England from the inner city and from advantaged suburbs. The study employed a treatment-control group design for testing the impact of several VMDL simulations on student learning in several content areas from traditional chemistry and physical science courses. The study employed a mixed qualitative and quantitative design. The quantitative part involved administering the Group Assessment of Logical Thinking (GALT) as well as post-tests that were topic specific. An Analysis of Covariance (ANCOVA) was conducted on the test scores with the GALT scores serving as a covariate. Results of the ANCOVA showed that students' understanding and performance were better in classes where teachers used the computer-based dynamic visualizations to complement their traditional teaching. GALT scores were significantly different among schools but very similar within schools. They were significant in adjusting post-test scores for pre-treatment differences for only two of the schools. The treatment groups outscored the control groups in all five comparisons. The mean differences reached statistical significance at the p < .01 level in only four of the comparisons. The qualitative part of the study involved classroom observations and student interviews. Analysis of classroom observations revealed a shift in classroom dynamics to more learner-centeredness with greater engagement by students, especially in classes that tended to have little student participation without the simulations. Analysis of the student interviews indicated that the dynamic visualizations made learning more enjoyable, helped with remembering, and enhanced students abilities to make connections between the nanoscopic and macroscopic science.

Visualizing Cloud Properties and Satellite Imagery: A Tool for Visualization and Information Integration

NASA Astrophysics Data System (ADS)

Chee, T.; Nguyen, L.; Smith, W. L., Jr.; Spangenberg, D.; Palikonda, R.; Bedka, K. M.; Minnis, P.; Thieman, M. M.; Nordeen, M.

2017-12-01

Providing public access to research products including cloud macro and microphysical properties and satellite imagery are a key concern for the NASA Langley Research Center Cloud and Radiation Group. This work describes a web based visualization tool and API that allows end users to easily create customized cloud product and satellite imagery, ground site data and satellite ground track information that is generated dynamically. The tool has two uses, one to visualize the dynamically created imagery and the other to provide access to the dynamically generated imagery directly at a later time. Internally, we leverage our practical experience with large, scalable application practices to develop a system that has the largest potential for scalability as well as the ability to be deployed on the cloud to accommodate scalability issues. We build upon NASA Langley Cloud and Radiation Group's experience with making real-time and historical satellite cloud product information, satellite imagery, ground site data and satellite track information accessible and easily searchable. This tool is the culmination of our prior experience with dynamic imagery generation and provides a way to build a "mash-up" of dynamically generated imagery and related kinds of information that are visualized together to add value to disparate but related information. In support of NASA strategic goals, our group aims to make as much scientific knowledge, observations and products available to the citizen science, research and interested communities as well as for automated systems to acquire the same information for data mining or other analytic purposes. This tool and the underlying API's provide a valuable research tool to a wide audience both as a standalone research tool and also as an easily accessed data source that can easily be mined or used with existing tools.

The capability of static and dynamic features to distinguish competent from genuinely expert practitioners in pediatric diagnosis.

PubMed

Loveday, Thomas; Wiggins, Mark W; Searle, Ben J; Festa, Marino; Schell, David

2013-02-01

The authors describe the development of a new, more objective method of distinguishing experienced competent nonexpert from expert practitioners within pediatric intensive care. Expert performance involves the acquisition and use of refined feature-event associations (cues) in the operational environment. Competent non-experts, although experienced, possess rudimentary cue associations in memory. Thus, they cannot respond as efficiently or as reliably as their expert counterparts, particularly when key diagnostic information is unavailable, such as that provided by dynamic cues. This study involved the application of four distinct tasks in which the use of relevant cues could be expected to increase both the accuracy and the efficiency of diagnostic performance. These tasks included both static and dynamic stimuli that were varied systematically. A total of 50 experienced pediatric intensive staff took part in the study. The sample clustered into two levels across the tasks: Participants who performed at a consistently high level throughout the four tasks were labeled experts, and participants who performed at a lower level throughout the tasks were labeled competent nonexperts. The groups differed in their responses to the diagnostic scenarios presented in two of the tasks and their ability to maintain performance in the absence of dynamic features. Experienced pediatricians can be decomposed into two groups on the basis of their capacity to acquire and use cues; these groups differ in their diagnostic accuracy and in their ability to maintain performance in the absence of dynamic features. The tasks may be used to identify practitioners who are failing to acquire expertise at a rate consistent with their experience, position, or training. This information may be used to guide targeted training efforts.

Differential renormalization-group generators for static and dynamic critical phenomena

NASA Astrophysics Data System (ADS)

Chang, T. S.; Vvedensky, D. D.; Nicoll, J. F.

1992-09-01

The derivation of differential renormalization-group (DRG) equations for applications to static and dynamic critical phenomena is reviewed. The DRG approach provides a self-contained closed-form representation of the Wilson renormalization group (RG) and should be viewed as complementary to the Callan-Symanzik equations used in field-theoretic approaches to the RG. The various forms of DRG equations are derived to illustrate the general mathematical structure of each approach and to point out the advantages and disadvantages for performing practical calculations. Otherwise, the review focuses upon the one-particle-irreducible DRG equations derived by Nicoll and Chang and by Chang, Nicoll, and Young; no attempt is made to provide a general treatise of critical phenomena. A few specific examples are included to illustrate the utility of the DRG approach: the large- n limit of the classical n-vector model (the spherical model), multi- or higher-order critical phenomena, and crit ical dynamics far from equilibrium. The large- n limit of the n-vector model is used to introduce the application of DRG equations to a well-known example, with exact solution obtained for the nonlinear trajectories, generating functions for nonlinear scaling fields, and the equation of state. Trajectory integrals and nonlinear scaling fields within the framework of ɛ-expansions are then discussed for tricritical crossover, and briefly for certain aspects of multi- or higher-order critical points, including the derivation of the Helmholtz free energy and the equation of state. The discussion then turns to critical dynamics with a development of the path integral formulation for general dynamic processes. This is followed by an application to a model far-from-equilibrium system that undergoes a phase transformation analogous to a second-order critical point, the Schlögl model for a chemical instability.

Facebook Groups as a Powerful and Dynamic Tool in Medical Education: Mixed-Method Study

PubMed Central

Schmidbauer, Moritz; Gradel, Maximilian; Ferch, Sabine; Antón, Sofía; Hoppe, Boj; Pander, Tanja; von der Borch, Philip; Pinilla, Severin; Fischer, Martin; Dimitriadis, Konstantinos

2017-01-01

Background Social networking sites, in particular Facebook, are not only predominant in students’ social life but are to varying degrees interwoven with the medical curriculum. Particularly, Facebook groups have been identified for their potential in higher education. However, there is a paucity of data on user types, content, and dynamics of study-related Facebook groups. Objective The aim of this study was to identify the role of study-related Facebook group use, characterize medical students that use or avoid using Facebook groups (demographics, participation pattern, and motivation), and analyze student posting behavior, covered topics, dynamics, and limitations in Facebook groups with regards to educational usage. Methods Using a multi-method approach (interviews, focus groups, and qualitative and quantitative analysis of Facebook posts), we analyzed two representative Facebook groups of medical preclinical semesters at Ludwig-Maximilians-University (LMU) Munich. Facebook primary posts and replies over one semester were extracted and evaluated by using thematic content analysis. We developed and applied a coding scheme for studying the frequency and distribution of these posts. Additionally, we interviewed students with various degrees of involvement in the groups, as well as “new minorities,” students not registered on Facebook. Results Facebook groups seem to have evolved as the main tool for medical students at LMU to complement the curriculum and to discuss study-related content. These Facebook groups are self-organizing and quickly adapt to organizational or subject-related challenges posed by the curriculum. A wide range of topics is covered, with a dominance of organization-related posts (58.35% [6916/11,853] of overall posts). By measuring reply rates and comments per category, we were able to identify learning tips and strategies, material sharing, and course content discussions as the most relevant categories. Rates of adequate replies in these categories ranged between 78% (11/14) and 100% (13/13), and the number of comments per post ranged from 8.4 to 13.7 compared with the average overall reply rate of 68.69% (1167/1699) and 3.9 comments per post. User typology revealed social media drivers (>30 posts per semester) as engines of group function, frequent users (11-30 posts), and a majority of average users acting rather as consumers or lurkers (1-10 posts). Conclusions For the moment, the medical faculty has no active involvement in these groups and therefore no influence on accuracy of information, professionalism, and ethical issues. Nevertheless, faculty could in the future benefit by extracting relevant information, identifying common problems, and understanding semester-related dynamics. PMID:29273572

DELPHI AND VALUES,

DTIC Science & Technology

MANAGEMENT PLANNING AND CONTROL, DECISION MAKING), (* DECISION MAKING , GROUP DYNAMICS), (*GROUP DYNAMICS, ATTITUDES(PSYCHOLOGY)), REASONING, REACTION(PSYCHOLOGY), PUBLIC OPINION, PERFORMANCE(HUMAN), QUESTIONNAIRES, FEEDBACK

Global distribution of NA1 genotype of respiratory syncytial virus and its evolutionary dynamics assessed from the past 11 years.

PubMed

Haider, Md Shakir Hussain; Deeba, Farah; Khan, Wajihul Hasan; Naqvi, Irshad H; Ali, Sher; Ahmed, Anwar; Broor, Shobha; Alsenaidy, Hytham A; Alsenaidy, Abdulrahman M; Dohare, Ravins; Parveen, Shama

2018-06-01

Respiratory syncytial virus (RSV) is a potent pathogen having global distribution. The main purpose of this study was to gain an insight into distribution pattern of the NA1 genotype of group A RSV across the globe together with its evolutionary dynamics. We focused on the second hypervariable region of the G protein gene and used the same for Phylogenetic, Bayesian and Network analyses. Eighteen percent of the samples collected from 500 symptomatic pediatric patients with acute respiratory tract infection (ARI) were found to be positive for RSV during 2011-15 from New Delhi, India. Of these, group B RSV was predominant and clustered into two different genotypes (BA and SAB4). Similarly, group A viruses clustered into two genotypes (NA1 and ON1). The data set from the group A viruses included 543 sequences from 23 different countries including 67 strains from India. The local evolutionary dynamics suggested consistent virus population of NA1 genotype in India during 2009 to 2014. The molecular clock analysis suggested that most recent common ancestor of group A and NA1 genotype have emerged in during the years 1953 and 2000, respectively. The global evolutionary rates of group A viruses and NA1 genotype were estimated to be 3.49 × 10 -3 (95% HPD, 2.90-4.17 × 10 -3 ) and 3.56 × 10 -3 (95% HPD, 2.91 × 10 -3 -4.18 × 10 -3 ) substitution/site/year, respectively. Analysis of the NA1 genotype of group A RSV reported during 11 years i.e. from 2004 to 2014 showed its dominance in 21 different countries across the globe reflecting its evolutionary dynamics. The Network analysis showed highly intricate but an inconsistent pattern of haplotypes of NA1 genotype circulating in the world. Present study seems to be first comprehensive attempt on global distribution and evolution of NA1 genotype augmenting the optimism towards the vaccine development. Copyright © 2018 Elsevier B.V. All rights reserved.

Monitoring Wetland Hydro-dynamics in the Prairie Pothole Region Using Landsat Time Series

NASA Astrophysics Data System (ADS)

Zhou, Q.; Rover, J.; Gallant, A.

2017-12-01

Wetlands provide a variety of ecosystem functions, while it is spatially and temporally dynamic. We mapped the dynamics of wetlands in the North Dakota Prairie Pothole Region using all available clear observations of Landsat sensor data from 1985 to 2014. We used a cluster analysis to group pixels exhibiting similar long-term spectral trends over seven Landsat bands, then applied the tasseled-cap transformation to evaluate the temporal characteristics of brightness, greenness, and wetness for each cluster. We tested relations between these three indices and hydrologic conditions, as represented by the Palmer Hydrological Drought Index (PHDI), using the cross-correlation analysis for each cluster performed over an eight-year moving window for the 30 years covered by the study. This temporal window size coincided with the timing of a major shift from a prolonged drought that occurred within the first eight years of the study period to wetter conditions that prevailed throughout the remaining years. The 20 cluster we produced represented a gradient from locations that continuously held water throughout the study period to locations that, at most, held water only for short periods in some years. The spatial distribution of the cluster groups reflected patterns of regional geologic and geomorphologic features. Comparisons of the PHDI to tasseled-cap wetness were the most straightforward to interpret among the results from the three indices. Wetness for most cluster groups had high positive correlations with PHDI during drought years, with the correlations reduced as the landscape entered a lengthy, wetter period; however, wetness generally remained highly and positively correlated with PHDI across all years for four cluster groups where the area exhibited two or more multi-year dry-wet cycles. These same four groups also had strong, generally negative correlations with tasseled-cap brightness. For other cluster groups, brightness often was strongly negatively correlated with the PHDI during the drought years, with the relation weakening for subsequent years of adequate or high moisture. Relations between tasseled-cap greenness and PHDI were highly variable among and within cluster groups. Results from this analysis support ongoing efforts to develop new products that characterize wetland dynamics.

Resting state cerebral blood flow with arterial spin labeling MRI in developing human brains.

PubMed

Liu, Feng; Duan, Yunsuo; Peterson, Bradley S; Asllani, Iris; Zelaya, Fernando; Lythgoe, David; Kangarlu, Alayar

2018-07-01

The development of brain circuits is coupled with changes in neurovascular coupling, which refers to the close relationship between neural activity and cerebral blood flow (CBF). Studying the characteristics of CBF during resting state in developing brain can be a complementary way to understand the functional connectivity of the developing brain. Arterial spin labeling (ASL), as a noninvasive MR technique, is particularly attractive for studying cerebral perfusion in children and even newborns. We have collected pulsed ASL data in resting state for 47 healthy subjects from young children to adolescence (aged from 6 to 20 years old). In addition to studying the developmental change of static CBF maps during resting state, we also analyzed the CBF time series to reveal the dynamic characteristics of CBF in differing age groups. We used the seed-based correlation analysis to examine the temporal relationship of CBF time series between the selected ROIs and other brain regions. We have shown the developmental patterns in both static CBF maps and dynamic characteristics of CBF. While higher CBF of default mode network (DMN) in all age groups supports that DMN is the prominent active network during the resting state, the CBF connectivity patterns of some typical resting state networks show distinct patterns of metabolic activity during the resting state in the developing brains. Copyright © 2018 European Paediatric Neurology Society. All rights reserved.

Dynamical relations for left ventricular ejection - Flow rate, momentum, force and impulse

NASA Technical Reports Server (NTRS)

Back, L. H.; Selzer, R. H.; Gordon, D. G.; Ledbetter, D. C.; Crawford, D. W.

1984-01-01

An investigation was carried out to quantitatively evaluate left ventricular volume flow rate, momentum, force and impulse derived from application of conservation principles for mass and momentum of blood within the ventricle during the ejection phase. An automated digital image processing system was developed and applied to left ventricular angiograms which are computer processed and analyzed frame by frame to determine the dynamical relations by numerical methods. The initial experience with force and impulse has indicated that neither quantity seemed to be a sensitive indicator of coronary artery disease as evaluated by qualitative angiography for the particular patient group studied. Utilization of the dynamical relations in evaluating human left ventricular performance requires improved means of measurement and interpretation of clinical studies.

Determination of Quantum Chemistry Based Force Fields for Molecular Dynamics Simulations of Aromatic Polymers

NASA Technical Reports Server (NTRS)

Jaffe, Richard; Langhoff, Stephen R. (Technical Monitor)

1995-01-01

Ab initio quantum chemistry calculations for model molecules can be used to parameterize force fields for molecular dynamics simulations of polymers. Emphasis in our research group is on using quantum chemistry-based force fields for molecular dynamics simulations of organic polymers in the melt and glassy states, but the methodology is applicable to simulations of small molecules, multicomponent systems and solutions. Special attention is paid to deriving reliable descriptions of the non-bonded and electrostatic interactions. Several procedures have been developed for deriving and calibrating these parameters. Our force fields for aromatic polyimide simulations will be described. In this application, the intermolecular interactions are the critical factor in determining many properties of the polymer (including its color).

Boolean Dynamic Modeling Approaches to Study Plant Gene Regulatory Networks: Integration, Validation, and Prediction.

PubMed

Velderraín, José Dávila; Martínez-García, Juan Carlos; Álvarez-Buylla, Elena R

2017-01-01

Mathematical models based on dynamical systems theory are well-suited tools for the integration of available molecular experimental data into coherent frameworks in order to propose hypotheses about the cooperative regulatory mechanisms driving developmental processes. Computational analysis of the proposed models using well-established methods enables testing the hypotheses by contrasting predictions with observations. Within such framework, Boolean gene regulatory network dynamical models have been extensively used in modeling plant development. Boolean models are simple and intuitively appealing, ideal tools for collaborative efforts between theorists and experimentalists. In this chapter we present protocols used in our group for the study of diverse plant developmental processes. We focus on conceptual clarity and practical implementation, providing directions to the corresponding technical literature.

Identification of a novel dynamic red blindness in human by event-related brain potentials.

PubMed

Zhang, Jiahua; Kong, Weijia; Yang, Zhongle

2010-12-01

Dynamic color is an important carrier that takes information in some special occupations. However, up to the present, there are no available and objective tests to evaluate dynamic color processing. To investigate the characteristics of dynamic color processing, we adopted two patterns of visual stimulus called "onset-offset" which reflected static color stimuli and "sustained moving" without abrupt mode which reflected dynamic color stimuli to evoke event-related brain potentials (ERPs) in primary color amblyopia patients (abnormal group) and subjects with normal color recognition ability (normal group). ERPs were recorded by Neuroscan system. The results showed that in the normal group, ERPs in response to the dynamic red stimulus showed frontal positive amplitudes with a latency of about 180 ms, a negative peak at about 240 ms and a peak latency of the late positive potential (LPP) in a time window between 290 and 580 ms. In the abnormal group, ERPs in response to the dynamic red stimulus were fully lost and characterized by vanished amplitudes between 0 and 800 ms. No significant difference was noted in ERPs in response to the dynamic green and blue stimulus between the two groups (P>0.05). ERPs of the two groups in response to the static red, green and blue stimulus were not much different, showing a transient negative peak at about 170 ms and a peak latency of LPP in a time window between 350 and 650 ms. Our results first revealed that some subjects who were not identified as color blindness under static color recognition could not completely apperceive a sort of dynamic red stimulus by ERPs, which was called "dynamic red blindness". Furthermore, these results also indicated that low-frequency ERPs induced by "sustained moving" may be a good and new method to test dynamic color perception competence.

Handwriting Development in Spanish Children With and Without Learning Disabilities: A Graphonomic Approach.

PubMed

Barrientos, Pablo

The central purpose of this study was to analyze the dynamics of handwriting movements in real time for Spanish students in early grades with and without learning disabilities. The sample consisted of 120 children from Grades 1 through 3 (primary education), classified into two groups: with learning disabilities and without learning disabilities. The Early Grade Writing Assessment tasks selected for this purpose were writing the alphabet in order from memory, alphabet copying in cursive and manuscript, and allograph selection. The dynamics of these four handwriting tasks were recorded using graphonomic tablets (type Wacom Intuos-4), Intuos Inking pens, and Eye and Pen 2 software. Several events were recorded across four different tasks: velocity, pressure, time invested in pauses, and automaticity. The results demonstrated significant graphonomic variations between groups across grades, depending on the type of task.

Mode and Intermediate Waters in Earth System Models

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

Gnanadesikan, Anand; Sarmiento, Jorge L.

This report describes work done as part of a joint Princeton-Johns Hopkins project to look at the impact of mode and intermediate waters in Earth System Models. The Johns Hopkins portion of this work focussed on the role of lateral mixing in ventilating such waters, with important implications for hypoxia, the uptake of anthropogenic carbon, the dynamics of El Nino and carbon pumps. The Johns Hopkins group also collaborated with the Princeton Group to help develop a watermass diagnostics framework.

The Dynamic Terrorist Threat: An Assessment of Group Motivations and Capabilities in a Changing World

DTIC Science & Technology

2004-01-01

performed in four programs: Aerospace Force Development; Manpower, Personnel, and Training; Resource Management ; and Strategy and Doctrine. Additional...in- capable group, such as the Palestinian Islamic Jihad (PIJ), would likely be just as challenging if it managed to increase its capabilities to the...2002, p. A1; “The Old West Comes to Israel,” Asia Times, November 16, 2002. 69McGeary (2001, p. 52). 70Jared Kotler , “Guerrillas to Study Curbing the

Report of Research at Technische Universitaet Darmstadt on Ultrahard Materials in the B-C-N-Si System

DTIC Science & Technology

2015-06-01

structure at the micro- and nanoscale. In other words, development of nanocomposites, multilayers, and superlattices via appropriate design and control of...C-B and C-N bonds as C-C and B-N bonds. Later, the same research group , based on first-principles total-energy, and dynamic phonon calculations...Vickers hardness values.7 Another research group employed an ab initio evolutionary algorithm42 to resolve the crystal structure of the observed

New applications of the renormalization group method in physics: a brief introduction.

PubMed

Meurice, Y; Perry, R; Tsai, S-W

2011-07-13

The renormalization group (RG) method developed by Ken Wilson more than four decades ago has revolutionized the way we think about problems involving a broad range of energy scales such as phase transitions, turbulence, continuum limits and bifurcations in dynamical systems. The Theme Issue provides articles reviewing recent progress made using the RG method in atomic, condensed matter, nuclear and particle physics. In the following, we introduce these articles in a way that emphasizes common themes and the universal aspects of the method.

Facet Joint Osteoarthritis Affects Spinal Segmental Motion in Degenerative Spondylolisthesis.

PubMed

Kitanaka, Shigeyuki; Takatori, Ryota; Arai, Yuji; Nagae, Masateru; Tonomura, Hitoshi; Mikami, Yasuo; Inoue, Nozomu; Ogura, Taku; Fujiwara, Hiroyoshi; Kubo, Toshikazu

2018-06-15

This is a retrospective clinical case series (case-control study). To clarify the influence of facet joint osteoarthritis (FJOA) on the pathology of degenerative spondylolisthesis (DS) using in vivo 3-dimensional image analysis. There are no radical treatments to prevent progression of DS in patients with lumbar spinal canal stenosis associated with DS. Therefore, an effective treatment method based on the pathology of DS should be developed. In total, 50 patients with lumbar spinal canal stenosis involving L4/5 who underwent dynamic computed tomography were divided into 2 groups: with DS [spondylolisthesis (Sp) group; 12 male, 14 female; mean age, 74 y]; and without DS (non-Sp group; 15 male, 9 female; mean age, 70 y). Degeneration of the intervertebral disk and FJOA at L4/5 were evaluated using magnetic resonance imaging. Disk and intervertebral foramen heights, the distance between the craniocaudal edges of the facet joint, and the interspinous distance were measured on dynamic computed tomographic images. Also, in vivo 3-dimensional segmental motion was evaluated using the volume merge method. There were no significant differences in degenerative findings for the intervertebral disk; however, progressive FJOA was detected in the Sp group. Dynamic changes in the distance between the craniocaudal edges of the facet joints were significantly larger in the Sp group. In this study, progressive FJOA and larger segmental motion in the distance between the craniocaudal edges of the facet joints were found in the Sp group. We clarified for the first time that DS involves ligament laxity due to FJOA that affects spinal segmental motion in vivo. We consider that a treatment method based on FJOA would be useful for treating patients with DS. Level IV.

Space life support engineering program

NASA Technical Reports Server (NTRS)

Seagrave, Richard C.

1991-01-01

This report covers the first six months of work performed under the NASA University Grant awarded to Iowa State University to perform research on two topics relating to the development of closed-loop long-term life support systems. A comprehensive study to develop software to simulate the dynamic operation of water reclamation systems in long-term closed-loop life support systems is being carried out as part of an overall program for the design of systems for a Mars voyage. This project is being done in parallel with a similar effort in the Department of Chemistry to develop durable accurate low-cost sensors for monitoring of trace chemical and biological species in recycled water supplies. Aspen-Plus software is being used on a group of high-performance workstations to develop the steady state descriptions for a number of existing technologies. Following completion, a dynamic simulation package will be developed for determining the response of such systems to changes in the metabolic needs of the crew and to upsets in system hardware performance.

Developing a Dynamic Pharmacophore Model for HIV-1 Integrase

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

Carlson, Heather A.; Masukawa, Keven M.; Rubins, Kathleen

2000-05-11

We present the first receptor-based pharmacophore model for HIV-1 integrase. The development of ''dynamic'' pharmacophore models is a new method that accounts for the inherent flexibility of the active site and aims to reduce the entropic penalties associated with binding a ligand. Furthermore, this new drug discovery method overcomes the limitation of an incomplete crystal structure of the target protein. A molecular dynamics (MD) simulation describes the flexibility of the uncomplexed protein. Many conformational models of the protein are saved from the MD simulations and used in a series of multi-unit search for interacting conformers (MUSIC) simulations. MUSIC is amore » multiple-copy minimization method, available in the BOSS program; it is used to determine binding regions for probe molecules containing functional groups that complement the active site. All protein conformations from the MD are overlaid, and conserved binding regions for the probe molecules are identified. Those conserved binding regions define the dynamic pharmacophore model. Here, the dynamic model is compared to known inhibitors of the integrase as well as a three-point, ligand-based pharmacophore model from the literature. Also, a ''static'' pharmacophore model was determined in the standard fashion, using a single crystal structure. Inhibitors thought to bind in the active site of HIV-1 integrase fit the dynamic model but not the static model. Finally, we have identified a set of compounds from the Available Chemicals Directory that fit the dynamic pharmacophore model, and experimental testing of the compounds has confirmed several new inhibitors.« less

Luminescent tunable polydots: Charge effects in confined geometry

DOE PAGES

Wijesinghe, Sidath; Maskey, Sabina; Perahia, Dvora; ...

2017-06-28

Long-lived soft nanoparticles, formed by conjugated polymers, constitute a new class of far-from-equilibrium responsive structures for nano-medicine. Tethering ionizable groups to the polymers enables functionality. However concurrently, the ionic groups perturb the delicate balance of interactions that governs these particles. Using fully atomistic molecular dynamics simulations, this study probed the effects of charged groups tethered to poly para phenylene ethynylene substituted by alkyl groups on the polymer conformation and dynamics in confined geometry. As a result, we find that the ionizable groups affect the entire shape of the polydots and impact the conformation and dynamics of the polymer.

Enhancing Student Learning in Food Engineering Using Computational Fluid Dynamics Simulations

ERIC Educational Resources Information Center

Wong, Shin Y.; Connelly, Robin K.; Hartel, Richard W.

2010-01-01

The current generation of students coming into food science and engineering programs is very visually oriented from their early experiences. To increase their interest in learning, new and visually appealing teaching materials need to be developed. Two diverse groups of students may be identified based on their math skills. Food science students…

Challenges in Sharing Information Effectively: Examples from Command and Control

ERIC Educational Resources Information Center

Sonnenwald, Diane H.

2006-01-01

Introduction: The goal of information sharing is to change a person's image of the world and to develop a shared working understanding. It is an essential component of collaboration. This paper examines barriers to sharing information effectively in dynamic group work situations. Method: Three types of battlefield training simulations were…

Planned Organizational Change; A Study in Change Dynamics.

ERIC Educational Resources Information Center

Jones, Garth N.

This study attempts to develop a broad model or concept, based largely on empirical evidence, which applies social science knowledge and methodology to the planning of change in corporations, armies, schools, hospitals, government, community groups, and other formal and informal organizations. Chapters 2,3, and 4 define and discuss the roles of…

The Internet as Potential Equalizer: New Leverage for Confronting Social Irresponsibility.

ERIC Educational Resources Information Center

Coombs, W. Timothy

1998-01-01

Contends activists have a new weapon (the Internet) which can change the organization-stakeholder dynamic. Uses recent development in stakeholder theory to explain how the Internet, when used effectively, can allow activist groups to become more powerful and to command the attention of organizations. Illustrates the theoretical points presented…

Foundations of Social Work Practice: A Graduate Text.

ERIC Educational Resources Information Center

Mattaini, Mark A., Ed.; Lowery, Christine T., Ed.; Meyer, Carol H., Ed.

As social work enters its second century, dynamic developments in practice and theory, the richness offered by multiple cultures and groups, and changing political and economic climates are potent forces driving advances in social work knowledge and practice. In the context of this professional evolution, this textbook wrestles with and builds on…

Caribbean and Central American Women's Feminist Inquiry through Theater-Based Action Research

ERIC Educational Resources Information Center

Sánchez Ares, Rocío

2015-01-01

Feminist action research interrogates gendered dynamics in the development of a collective consciousness. A group of immigrant Latina women (Latinas) from the Caribbean and Central America employed community-based theater as an instrument to mobilize diverse audiences against discriminatory practices and policies. Based on their theater work, I…

Resource Allocation Procedure at Queensland University: A Dynamic Modelling Project.

ERIC Educational Resources Information Center

Galbraith, Peter L.; Carss, Brian W.

A structural reorganization of the University of Queensland, Australia, was undertaken to promote efficient resource management, and a resource allocation model was developed to aid in policy evaluation and planning. The operation of the restructured system was based on creating five resource groups to manage the distribution of academic resources…

Common Ground for Action Software and Professional Development to Support Online Deliberation in Classrooms

ERIC Educational Resources Information Center

Christelle, Andrea; Dillard, Kara N.; Lindaman, Kara

2018-01-01

The Common Ground for Action (CGA) online deliberation platform is a dynamic tool designed to encourage diverse group members to identify collective responses to deeply controversial or "wicked" public problems that have no simple solution. The program promotes authentic deliberation, while minimizing the tactics of horse-trading and…

Dynamic metabolome profiling reveals significant metabolic changes during grain development of bread wheat (Triticum aestivum L.).

PubMed

Zhen, Shoumin; Dong, Kun; Deng, Xiong; Zhou, Jiaxing; Xu, Xuexin; Han, Caixia; Zhang, Wenying; Xu, Yanhao; Wang, Zhimin; Yan, Yueming

2016-08-01

Metabolites in wheat grains greatly influence nutritional values. Wheat provides proteins, minerals, B-group vitamins and dietary fiber to humans. These metabolites are important to human health. However, the metabolome of the grain during the development of bread wheat has not been studied so far. In this work the first dynamic metabolome of the developing grain of the elite Chinese bread wheat cultivar Zhongmai 175 was analyzed, using non-targeted gas chromatography/mass spectrometry (GC/MS) for metabolite profiling. In total, 74 metabolites were identified over the grain developmental stages. Metabolite-metabolite correlation analysis revealed that the metabolism of amino acids, carbohydrates, organic acids, amines and lipids was interrelated. An integrated metabolic map revealed a distinct regulatory profile. The results provide information that can be used by metabolic engineers and molecular breeders to improve wheat grain quality. The present metabolome approach identified dynamic changes in metabolite levels, and correlations among such levels, in developing seeds. The comprehensive metabolic map may be useful when breeding programs seek to improve grain quality. The work highlights the utility of GC/MS-based metabolomics, in conjunction with univariate and multivariate data analysis, when it is sought to understand metabolic changes in developing seeds. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Dynamical heterogeneities of rotational motion in room temperature ionic liquids evidenced by molecular dynamics simulations

NASA Astrophysics Data System (ADS)

Usui, Kota; Hunger, Johannes; Bonn, Mischa; Sulpizi, Marialore

2018-05-01

Room temperature ionic liquids (RTILs) have been shown to exhibit spatial heterogeneity or structural heterogeneity in the sense that they form hydrophobic and ionic domains. Yet studies of the relationship between this structural heterogeneity and the ˜picosecond motion of the molecular constituents remain limited. In order to obtain insight into the time scales relevant to this structural heterogeneity, we perform molecular dynamics simulations of a series of RTILs. To investigate the relationship between the structures, i.e., the presence of hydrophobic and ionic domains, and the dynamics, we gradually increase the size of the hydrophobic part of the cation from ethylammonium nitrate (EAN), via propylammonium nitrate (PAN), to butylammonium nitrate (BAN). The two ends of the organic cation, namely, the charged Nhead-H group and the hydrophobic Ctail-H group, exhibit rotational dynamics on different time scales, evidencing dynamical heterogeneity. The dynamics of the Nhead-H group is slower because of the strong coulombic interaction with the nitrate counter-ionic anions, while the dynamics of the Ctail-H group is faster because of the weaker van der Waals interaction with the surrounding atoms. In particular, the rotation of the Nhead-H group slows down with increasing cationic chain length, while the rotation of the Ctail-H group shows little dependence on the cationic chain length, manifesting that the dynamical heterogeneity is enhanced with a longer cationic chain. The slowdown of the Nhead-H group with increasing cationic chain length is associated with a lower number of nitrate anions near the Nhead-H group, which presumably results in the increase of the energy barrier for the rotation. The sensitivity of the Nhead-H rotation to the number of surrounding nitrate anions, in conjunction with the varying number of nitrate anions, gives rise to a broad distribution of Nhead-H reorientation times. Our results suggest that the asymmetry of the cations and the larger excluded volume for longer cationic chain are important for both the structural heterogeneity and the dynamical heterogeneities. The observed dynamical heterogeneities may affect the rates of chemical reactions depending on where the reactants are solvated in ionic liquids and provide an additional guideline for the design of RTILs as solvents.

Incorporating spatial constraint in co-activation pattern analysis to explore the dynamics of resting-state networks: An application to Parkinson's disease.

PubMed

Zhuang, Xiaowei; Walsh, Ryan R; Sreenivasan, Karthik; Yang, Zhengshi; Mishra, Virendra; Cordes, Dietmar

2018-05-15

The dynamics of the brain's intrinsic networks have been recently studied using co-activation pattern (CAP) analysis. The CAP method relies on few model assumptions and CAP-based measurements provide quantitative information of network temporal dynamics. One limitation of existing CAP-related methods is that the computed CAPs share considerable spatial overlap that may or may not be functionally distinct relative to specific network dynamics. To more accurately describe network dynamics with spatially distinct CAPs, and to compare network dynamics between different populations, a novel data-driven CAP group analysis method is proposed in this study. In the proposed method, a dominant-CAP (d-CAP) set is synthesized across CAPs from multiple clustering runs for each group with the constraint of low spatial similarities among d-CAPs. Alternating d-CAPs with less overlapping spatial patterns can better capture overall network dynamics. The number of d-CAPs, the temporal fraction and spatial consistency of each d-CAP, and the subject-specific switching probability among all d-CAPs are then calculated for each group and used to compare network dynamics between groups. The spatial dissimilarities among d-CAPs computed with the proposed method were first demonstrated using simulated data. High consistency between simulated ground-truth and computed d-CAPs was achieved, and detailed comparisons between the proposed method and existing CAP-based methods were conducted using simulated data. In an effort to physiologically validate the proposed technique and investigate network dynamics in a relevant brain network disorder, the proposed method was then applied to data from the Parkinson's Progression Markers Initiative (PPMI) database to compare the network dynamics in Parkinson's disease (PD) and normal control (NC) groups. Fewer d-CAPs, skewed distribution of temporal fractions of d-CAPs, and reduced switching probabilities among final d-CAPs were found in most networks in the PD group, as compared to the NC group. Furthermore, an overall negative association between switching probability among d-CAPs and disease severity was observed in most networks in the PD group as well. These results expand upon previous findings from in vivo electrophysiological recording studies in PD. Importantly, this novel analysis also demonstrates that changes in network dynamics can be measured using resting-state fMRI data from subjects with early stage PD. Copyright © 2018 Elsevier Inc. All rights reserved.

A dynamic and ultrafast group delay tuning mechanism in two microcavities side-coupled with a waveguide system

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

Wang, Boyun; Wang, Tao, E-mail: wangtao@hust.edu.cn; Tang, Jian

2014-10-07

We theoretically propose a dynamic and ultrafast group delay tuning mechanism in two microcavities side-coupled to a waveguide system through external optical pump beams. The optical Kerr effect modulation method is applied to improve tuning rate with response time of subpicoseconds or even femtoseconds. The group delay of an all-optical analog to electromagnetically induced transparency effect can be controlled by tuning either the frequency of photonic crystal microcavities or the propagation phase of line waveguide. Group delay is controlled between 5.88 and 70.98 ps by dynamically tuning resonant frequencies of the microcavities. Alternatively, the group delay is controlled between 1.86more » and 12.08 ps by dynamically tuning the propagation phase of line waveguide. All observed schemes are analyzed rigorously through finite-difference time-domain simulations and coupled-mode formalism. Results show a new direction toward microstructure integration optical pulse trapping and all-optical dynamical storage of light devices in optical communication and quantum information processing.« less

Influence of the leaving group on the dynamics of a gas-phase SN2 reaction

NASA Astrophysics Data System (ADS)

Stei, Martin; Carrascosa, Eduardo; Kainz, Martin A.; Kelkar, Aditya H.; Meyer, Jennifer; Szabó, István; Czakó, Gábor; Wester, Roland

2016-02-01

In addition to the nucleophile and solvent, the leaving group has a significant influence on SN2 nucleophilic substitution reactions. Its role is frequently discussed with respect to reactivity, but its influence on the reaction dynamics remains unclear. Here, we uncover the influence of the leaving group on the gas-phase dynamics of SN2 reactions in a combined approach of crossed-beam imaging and dynamics simulations. We have studied the reaction F- + CH3Cl and compared it to F- + CH3I. For the two leaving groups, Cl and I, we find very similar structures and energetics, but the dynamics show qualitatively different features. Simple scaling of the leaving group mass does not explain these differences. Instead, the relevant impact parameters for the reaction mechanisms are found to be crucial and the differences are attributed to the relative orientation of the approaching reactants. This effect occurs on short timescales and may also prevail in solution-phase conditions.

Influence of the leaving group on the dynamics of a gas-phase SN2 reaction.

PubMed

Stei, Martin; Carrascosa, Eduardo; Kainz, Martin A; Kelkar, Aditya H; Meyer, Jennifer; Szabó, István; Czakó, Gábor; Wester, Roland

2016-02-01

In addition to the nucleophile and solvent, the leaving group has a significant influence on SN2 nucleophilic substitution reactions. Its role is frequently discussed with respect to reactivity, but its influence on the reaction dynamics remains unclear. Here, we uncover the influence of the leaving group on the gas-phase dynamics of SN2 reactions in a combined approach of crossed-beam imaging and dynamics simulations. We have studied the reaction F(-) + CH3Cl and compared it to F(-) + CH3I. For the two leaving groups, Cl and I, we find very similar structures and energetics, but the dynamics show qualitatively different features. Simple scaling of the leaving group mass does not explain these differences. Instead, the relevant impact parameters for the reaction mechanisms are found to be crucial and the differences are attributed to the relative orientation of the approaching reactants. This effect occurs on short timescales and may also prevail in solution-phase conditions.

What Motivates Biology Instructors to Engage and Persist in Teaching Professional Development?

PubMed Central

McCourt, Jill S.; Andrews, Tessa C.; Knight, Jennifer K.; Merrill, John E.; Nehm, Ross H.; Pelletreau, Karen N.; Prevost, Luanna B.; Smith, Michelle K.; Urban-Lurain, Mark; Lemons, Paula P.

2017-01-01

We conducted a study of 19 biology instructors participating in small, local groups at six research-intensive universities connected to the Automated Analysis of Constructed Response (AACR) project (www.msu.edu/∼aacr). Our aim was to uncover participants’ motivation to persist in a long-term teaching professional development effort, a topic that is understudied in discipline-based educational research. We interviewed each participant twice over a 2-year period and conducted qualitative analyses on the data, using expectancy-value theory as a framework for considering motivation. Our analyses revealed that motivation among instructors was high due to their enjoyment of the AACR groups. The high level of motivation is further explained by the fact that AACR groups facilitated instructor involvement with the larger AACR project. We also found that group dynamics encouraged persistence; instructors thought they might never talk with colleagues about teaching in the absence of AACR groups; and groups were perceived to have a low-enough time requirement to warrant sustained involvement. We conclude that instructors have persisted in AACR groups because the groups provided great value with limited cost. The characterization of instructor experiences described here can contribute to a better understanding of faculty needs in teaching professional development. PMID:28821539

Examining Teacher Instructional Leadership within the Small Group Dynamics of Collegial Groups.

ERIC Educational Resources Information Center

Keedy, John L.

1999-01-01

Examined the dynamics of teacher leadership, using two teacher collegial groups as a small-group context. After discussing teacher leadership and teacher-mediation effects, describes data collection, which involved observations, interviews, surveys, and document mining. Results indicated that teacher-mediation effects did not counter teacher…

Overview af MSFC's Applied Fluid Dynamics Analysis Group Activities

NASA Technical Reports Server (NTRS)

Garcia, Roberto; Griffin, Lisa; Williams, Robert

2004-01-01

This paper presents viewgraphs on NASA Marshall Space Flight Center's Applied Fluid Dynamics Analysis Group Activities. The topics include: 1) Status of programs at MSFC; 2) Fluid Mechanics at MSFC; 3) Relevant Fluid Dynamics Activities at MSFC; and 4) Shuttle Return to Flight.

A Computerized Asthma Outcomes Measure Is Feasible for Disease Management.

PubMed

Turner-Bowker, Diane M; Saris-Baglama, Renee N; Anatchkova, Milena; Mosen, David M

2010-04-01

OBJECTIVE: To develop and test an online assessment referred to as the ASTHMA-CAT (computerized adaptive testing), a patient-based asthma impact, control, and generic health-related quality of life (HRQOL) measure. STUDY DESIGN: Cross-sectional pilot study of the ASTHMA-CAT's administrative feasibility in a disease management population. METHODS: The ASTHMA-CAT included a dynamic or static Asthma Impact Survey (AIS), Asthma Control Test, and SF-8 Health Survey. A sample of clinician-diagnosed adult asthmatic patients (N = 114) completed the ASTHMA-CAT. Results were used to evaluate administrative feasibility of the instrument and psychometric performance of the dynamic AIS relative to the static AIS. A prototype aggregate (group-level) report was developed and reviewed by care providers. RESULTS: Online administration of the ASTHMA-CAT was feasible for patients in disease management. The dynamic AIS functioned well compared with the static AIS in preliminary studies evaluating response burden, precision, and validity. Providers found reports to be relevant, useful, and applicable for care management. CONCLUSION: The ASTHMA-CAT may facilitate asthma care management.

The structure of social exchange in self-help support groups: development of a measure.

PubMed

Brown, Louis D; Tang, Xiaohui; Hollman, Ruth L

2014-03-01

Self-help support groups are indigenous community resources designed to help people manage a variety of personal challenges, from alcohol abuse to xeroderma pigmentosum. The social exchanges that occur during group meetings are central to understanding how people benefit from participation. This paper examines the different types of social exchange behaviors that occur during meetings, using two studies to develop empirically distinct scales that reliably measure theoretically important types of exchange. Resource theory informed the initial measurement development efforts. Exploratory factor analyses from the first study led to revisions in the factor structure of the social exchange scales. The revised measure captured the exchange of emotional support, experiential information, humor, unwanted behaviors, and exchanges outside meetings. Confirmatory factor analyses from a follow-up study with a different sample of self-help support groups provided good model fit, suggesting the revised structure accurately represented the data. Further, the scales demonstrated good convergent and discriminant validity with related constructs. Future research can use the scales to identify aspects of social exchange that are most important in improving health outcomes among self-help support group participants. Groups can use the scales in practice to celebrate strengths and address weaknesses in their social exchange dynamics.

Group dynamics.

PubMed

Scandiffio, A L

1990-12-01

Group dynamics play a significant role within any organization, culture, or unit. The important thing to remember with any of these structures is that they are made up of people--people with different ideas, motivations, background, and sometimes different agendas. Most groups, formal or informal, look for a leader in an effort to maintain cohesiveness of the unit. At times, that cultural bond must be developed; once developed, it must be nurtured. There are also times that one of the group no longer finds the culture comfortable and begins to act out behaviorally. It is these times that become trying for the leader as she or he attempts to remain objective when that which was once in the building phase of group cohesiveness starts to fall apart. At all times, the manager must continue to view the employee creating the disturbance as an integral part of the group. It is at this time that it is beneficial to perceive the employee exhibiting problem behaviors as a special employee, as one who needs the benefit of your experience and skills, as one who is still part of the group. It is also during this time that the manager should focus upon her or his own views in the area of power, communication, and the corporate culture of the unit that one has established before attempting to understand another's point of view. Once we understand our own motivation and accept ourselves, it is then that we may move on to offer assistance to another. Once we understand our insecurities recognizing staff dysfunction as a symptom of system dysfunction will not be so threatening to the concept of the manager that we perceive ourselves to be. It takes a secure person to admit that she or he favors staff before deciding to do something to change things. The important thing to know is that it can be done. The favored staff can find a new way of relating to others, the special employee can find new modes of behavior (and even find self-esteem in the process), the group can find new ways of interacting, and the corporate culture can boast of a leader with new views at the helm. In marriage, it takes only two; in a group, it takes a lot more. The dynamics of many people interacting may present difficulties at times; however, the birth of the bond of that group is well worth the effort. Ask any manager.

Relationships among age, gender, anthropometric characteristics, and dynamic balance in children 5 to 12 years old.

PubMed

Butz, Sarah M; Sweeney, Jane K; Roberts, Pamela L; Rauh, Mitchell J

2015-01-01

To examine relationships among age, gender, anthropometrics, and dynamic balance. Height, weight, and arm and foot length were measured in 160 children with typical development aged 5 to 12 years. Dynamic balance was assessed using the Timed Up and Go (TUG) test, Pediatric Reach Test (PRT), and Pediatric Balance Scale (PBS). Moderate to good positive relationships (r = 0.61 and r = 0.56) were found between increasing age and PRT and PBS scores. A fair negative relationship (r = -0.49) was observed between age and TUG test. No significant gender-by-age group difference was observed. Age had the strongest influence on TUG and PBS scores; arm length had the strongest influence on PRT scores. Dynamic balance ability is directly related to chronological age. Age and arm length have the strongest relationships with balance scores. These findings may assist pediatric therapists in selecting dynamic balance tests according to age rather than specific diagnosis.

A Mathematical Framework for the Complex System Approach to Group Dynamics: The Case of Recovery House Social Integration.

PubMed

Light, John M; Jason, Leonard A; Stevens, Edward B; Callahan, Sarah; Stone, Ariel

2016-03-01

The complex system conception of group social dynamics often involves not only changing individual characteristics, but also changing within-group relationships. Recent advances in stochastic dynamic network modeling allow these interdependencies to be modeled from data. This methodology is discussed within a context of other mathematical and statistical approaches that have been or could be applied to study the temporal evolution of relationships and behaviors within small- to medium-sized groups. An example model is presented, based on a pilot study of five Oxford House recovery homes, sober living environments for individuals following release from acute substance abuse treatment. This model demonstrates how dynamic network modeling can be applied to such systems, examines and discusses several options for pooling, and shows how results are interpreted in line with complex system concepts. Results suggest that this approach (a) is a credible modeling framework for studying group dynamics even with limited data, (b) improves upon the most common alternatives, and (c) is especially well-suited to complex system conceptions. Continuing improvements in stochastic models and associated software may finally lead to mainstream use of these techniques for the study of group dynamics, a shift already occurring in related fields of behavioral science.

Dynamical signatures of isometric force control as a function of age, expertise, and task constraints.

PubMed

Vieluf, Solveig; Sleimen-Malkoun, Rita; Voelcker-Rehage, Claudia; Jirsa, Viktor; Reuter, Eva-Maria; Godde, Ben; Temprado, Jean-Jacques; Huys, Raoul

2017-07-01

From the conceptual and methodological framework of the dynamical systems approach, force control results from complex interactions of various subsystems yielding observable behavioral fluctuations, which comprise both deterministic (predictable) and stochastic (noise-like) dynamical components. Here, we investigated these components contributing to the observed variability in force control in groups of participants differing in age and expertise level. To this aim, young (18-25 yr) as well as late middle-aged (55-65 yr) novices and experts (precision mechanics) performed a force maintenance and a force modulation task. Results showed that whereas the amplitude of force variability did not differ across groups in the maintenance tasks, in the modulation task it was higher for late middle-aged novices than for experts and higher for both these groups than for young participants. Within both tasks and for all groups, stochastic fluctuations were lowest where the deterministic influence was smallest. However, although all groups showed similar dynamics underlying force control in the maintenance task, a group effect was found for deterministic and stochastic fluctuations in the modulation task. The latter findings imply that both components were involved in the observed group differences in the variability of force fluctuations in the modulation task. These findings suggest that between groups the general characteristics of the dynamics do not differ in either task and that force control is more affected by age than by expertise. However, expertise seems to counteract some of the age effects. NEW & NOTEWORTHY Stochastic and deterministic dynamical components contribute to force production. Dynamical signatures differ between force maintenance and cyclic force modulation tasks but hardly between age and expertise groups. Differences in both stochastic and deterministic components are associated with group differences in behavioral variability, and observed behavioral variability is more strongly task dependent than person dependent. Copyright © 2017 the American Physiological Society.

Human seizures couple across spatial scales through travelling wave dynamics

NASA Astrophysics Data System (ADS)

Martinet, L.-E.; Fiddyment, G.; Madsen, J. R.; Eskandar, E. N.; Truccolo, W.; Eden, U. T.; Cash, S. S.; Kramer, M. A.

2017-04-01

Epilepsy--the propensity toward recurrent, unprovoked seizures--is a devastating disease affecting 65 million people worldwide. Understanding and treating this disease remains a challenge, as seizures manifest through mechanisms and features that span spatial and temporal scales. Here we address this challenge through the analysis and modelling of human brain voltage activity recorded simultaneously across microscopic and macroscopic spatial scales. We show that during seizure large-scale neural populations spanning centimetres of cortex coordinate with small neural groups spanning cortical columns, and provide evidence that rapidly propagating waves of activity underlie this increased inter-scale coupling. We develop a corresponding computational model to propose specific mechanisms--namely, the effects of an increased extracellular potassium concentration diffusing in space--that support the observed spatiotemporal dynamics. Understanding the multi-scale, spatiotemporal dynamics of human seizures--and connecting these dynamics to specific biological mechanisms--promises new insights to treat this devastating disease.

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

Walker, La Tonya Nicole; Malczynski, Leonard A.

DYNAMO is a computer program for building and running 'continuous' simulation models. It was developed by the Industrial Dynamics Group at the Massachusetts Institute of Technology for simulating dynamic feedback models of business, economic, and social systems. The history of the system dynamics method since 1957 includes many classic models built in DYANMO. It was not until the late 1980s that software was built to take advantage of the rise of personal computers and graphical user interfaces that DYNAMO was supplanted. There is much learning and insight to be gained from examining the DYANMO models and their accompanying research papers.more » We believe that it is a worthwhile exercise to convert DYNAMO models to more recent software packages. We have made an attempt to make it easier to turn these models into a more current system dynamics software language, Powersim © Studio produced by Powersim AS 2 of Bergen, Norway. This guide shows how to convert DYNAMO syntax into Studio syntax.« less

Framing of task performance strategies: effects on performance in a multiattribute dynamic decision making environment.

PubMed

Nygren, T E

1997-09-01

It is well documented that the way a static choice task is "framed" can dramatically alter choice behavior, often leading to observable preference reversals. This framing effect appears to result from perceived changes in the nature or location of a person's initial reference point, but it is not clear how framing effects might generalize to performance on dynamic decision making tasks that are characterized by high workload, time constraints, risk, or stress. A study was conducted to examine the hypothesis that framing can introduce affective components to the decision making process and can influence, either favorably (positive frame) or adversely (negative frame), the implementation and use of decision making strategies in dynamic high-workload environments. Results indicated that negative frame participants were significantly impaired in developing and employing a simple optimal decision strategy relative to a positive frame group. Discussion focuses on implications of these results for models of dynamic decision making.

Dynamic analysis environment for nuclear forensic analyses

NASA Astrophysics Data System (ADS)

Stork, C. L.; Ummel, C. C.; Stuart, D. S.; Bodily, S.; Goldblum, B. L.

2017-01-01

A Dynamic Analysis Environment (DAE) software package is introduced to facilitate group inclusion/exclusion method testing, evaluation and comparison for pre-detonation nuclear forensics applications. Employing DAE, the multivariate signatures of a questioned material can be compared to the signatures for different, known groups, enabling the linking of the questioned material to its potential process, location, or fabrication facility. Advantages of using DAE for group inclusion/exclusion include built-in query tools for retrieving data of interest from a database, the recording and documentation of all analysis steps, a clear visualization of the analysis steps intelligible to a non-expert, and the ability to integrate analysis tools developed in different programming languages. Two group inclusion/exclusion methods are implemented in DAE: principal component analysis, a parametric feature extraction method, and k nearest neighbors, a nonparametric pattern recognition method. Spent Fuel Isotopic Composition (SFCOMPO), an open source international database of isotopic compositions for spent nuclear fuels (SNF) from 14 reactors, is used to construct PCA and KNN models for known reactor groups, and 20 simulated SNF samples are utilized in evaluating the performance of these group inclusion/exclusion models. For all 20 simulated samples, PCA in conjunction with the Q statistic correctly excludes a large percentage of reactor groups and correctly includes the true reactor of origination. Employing KNN, 14 of the 20 simulated samples are classified to their true reactor of origination.

Difficult incidents and tutor interventions in problem-based learning tutorials.

PubMed

Kindler, Pawel; Grant, Christopher; Kulla, Steven; Poole, Gary; Godolphin, William

2009-09-01

Tutors report difficult incidents and distressing conflicts that adversely affect learning in their problem-based learning (PBL) groups. Faculty development (training) and peer support should help them to manage this. Yet our understanding of these problems and how to deal with them often seems inadequate to help tutors. The aim of this study was to categorise difficult incidents and the interventions that skilled tutors used in response, and to determine the effectiveness of those responses. Thirty experienced and highly rated tutors in our Year 1 and 2 medical curriculum took part in semi-structured interviews to: identify and describe difficult incidents; describe how they responded, and assess the success of each response. Recorded and transcribed data were analysed thematically to develop typologies of difficult incidents and interventions and compare reported success or failure. The 94 reported difficult incidents belonged to the broad categories 'individual student' or 'group dynamics'. Tutors described 142 interventions in response to these difficult incidents, categorised as: (i) tutor intervenes during tutorial; (ii) tutor gives feedback outside tutorial, or (iii) student or group intervenes. Incidents in the 'individual student' category were addressed relatively unsuccessfully (effective < 50% of the time) by response (i), but with moderate success by response (ii) and successfully (> 75% of the time) by response (iii). None of the interventions worked well when used in response to problems related to 'group dynamics'. Overall, 59% of the difficult incidents were dealt with successfully. Dysfunctional PBL groups can be highly challenging, even for experienced and skilled tutors. Within-tutorial feedback, the treatment that tutors are most frequently advised to apply, was often not effective. Our study suggests that the collective responsibility of the group, rather than of the tutor, to deal with these difficulties should be emphasised.

Early years of Computational Statistical Mechanics

NASA Astrophysics Data System (ADS)

Mareschal, Michel

2018-05-01

Evidence that a model of hard spheres exhibits a first-order solid-fluid phase transition was provided in the late fifties by two new numerical techniques known as Monte Carlo and Molecular Dynamics. This result can be considered as the starting point of computational statistical mechanics: at the time, it was a confirmation of a counter-intuitive (and controversial) theoretical prediction by J. Kirkwood. It necessitated an intensive collaboration between the Los Alamos team, with Bill Wood developing the Monte Carlo approach, and the Livermore group, where Berni Alder was inventing Molecular Dynamics. This article tells how it happened.

Representation of Renormalization Group Functions By Nonsingular Integrals in a Model of the Critical Dynamics of Ferromagnets: The Fourth Order of The ɛ-Expansion

NASA Astrophysics Data System (ADS)

Adzhemyan, L. Ts.; Vorob'eva, S. E.; Ivanova, E. V.; Kompaniets, M. V.

2018-04-01

Using the representation for renormalization group functions in terms of nonsingular integrals, we calculate the dynamical critical exponents in the model of critical dynamics of ferromagnets in the fourth order of the ɛ-expansion. We calculate the Feynman diagrams using the sector decomposition technique generalized to critical dynamics problems.

Group Effects on Individual Attitudes Toward Social Responsibility.

PubMed

Secchi, Davide; Bui, Hong T M

2018-01-01

This study uses a quasi-experimental design to investigate what happens to individual socially responsible attitudes when they are exposed to group dynamics. Findings show that group engagement increases individual attitudes toward social responsibility. We also found that individuals with low attitudes toward social responsibility are more likely to change their opinions when group members show more positive attitudes toward social responsibility. Conversely, individuals with high attitudes do not change much, independent of group characteristics. To better analyze the effect of group dynamics, the study proposes to split social responsibility into relative and absolute components. Findings show that relative social responsibility is correlated with but different from absolute social responsibility although the latter is more susceptible than the former to group dynamics.

Affect and Therapeutic Process in Groups for Chronically Mentally Ill Persons

PubMed Central

Stone, Walter N.

1998-01-01

A dynamic group treatment model for chronically ill persons allowing them to determine the frequency of attendance empowers the members and potentiates group development. This format respects patients' needs for space as represented by missed meetings. In this context, absences are formulated as self-protective and self-stabilizing acts rather than as resistance. In an accepting, supportive environment, members can be helped to explore affects and gain insight into their behaviors. A clinical example illustrates patients' examination of the meaning of missing and attending sessions, with particular focus on intensity of involvement, autonomy, and control. In the process of testing the therapist and group, members show capacity to gain insight into recent in-group and extra-group behaviors.(The Journal of Psychotherapy Practice and Research 1998; 7:208–216) PMID:9631342

The effect of a rhythmic gymnastics program on the dynamic balance ability of individuals with intellectual disability.

PubMed

Fotiadou, Eleni G; Neofotistou, Konstantina H; Sidiropoulou, Maria P; Tsimaras, Vasilios K; Mandroukas, Athanasios K; Angelopoulou, Nickoletta A

2009-10-01

The purpose of this study was to examine the effect of a rhythmic gymnastics program on the dynamic balance ability of a group of adults with intellectual disability (ID). The sample consisted of 18 adults with ID. The control group consisted of 8 adults and an intervention group of 10. The subjects were assigned to each group according to their desire to participate or not in the intervention program. Both groups were comparable in terms of age, weight, height, IQ, and socioeconomic background. The intervention group received a 12-week rhythmic gymnastics program at a frequency of 3 lessons per week, of 45 minutes. The methods of data collection included pre/post-test measurements of the dynamic balance for all subjects of both groups. The dynamic balance ability was measured by means of a balance deck (Lafayette) and was determined by the number of seconds the subject could remain standing on the platform of the stabilometer in durations of 30-, 45-, and 60-second intervals. As the results indicated, the intervention group showed a statistically significant improvement (p < 0.05) in terms of dynamic balance ability in each interval after the application of the rhythmic gymnastics program when compared with the control group. It is concluded that adults with ID can improve their balance ability with the application of a well-designed rhythmic gymnastics program.

The Interplay Between Language, Gesture, and Affect During Communicative Transition: A Dynamic Systems Approach

PubMed Central

Parladé, Meaghan V.; Iverson, Jana M.

2012-01-01

From a dynamic systems perspective, transition points in development are times of increased instability, during which behavioral patterns are susceptible to temporary decoupling. This study investigated the impact of the vocabulary spurt on existing patterns of communicative coordination. Eighteen typically developing infants were videotaped at home 1 month before, at, and after the vocabulary spurt. Infants were identified as spurters if they underwent a discrete phase transition in vocabulary development (marked by an inflection point), and compared with a group of nonspurters whose word-learning rates followed a trajectory of continuous change. Relative to surrounding sessions, there were significant reductions in overall coordination of communicative behaviors and in words produced in coordination at the vocabulary spurt session for infants who experienced more dramatic vocabulary growth. In contrast, nonspurters demonstrated little change across sessions. Findings underscore the importance of transitions as opportunities for observing processes of developmental change. PMID:21219063

A Tribute to J. C. Sprott

NASA Astrophysics Data System (ADS)

Nazarimehr, Fahimeh; Jafari, Sajad; Chen, Guanrong; Kapitaniak, Tomasz; Kuznetsov, Nikolay V.; Leonov, Gennady A.; Li, Chunbiao; Wei, Zhouchao

2017-12-01

In honor of his 75th birthday, we review the prominent works of Professor Julien Clinton Sprott in chaos and nonlinear dynamics. We categorize his works into three important groups. The first and most important group is identifying new dynamical systems with special properties. He has proposed different chaotic maps, flows, complex variable systems, nonautonomous systems, partial differential equations, fractional-order systems, delay differential systems, spatiotemporal systems, artificial neural networks, and chaotic electrical circuits. He has also studied dynamical properties of complex systems such as bifurcations and basins of attraction. He has done work on generating fractal art. He has examined models of real-world systems that exhibit chaos. The second group of his works comprise control and synchronization of chaos. Finally, the third group is extracting dynamical properties of systems using time-series analysis. This paper highlights the impact of Sprott’s work on the promotion of nonlinear dynamics.

Effects of virtual reality programs on balance in functional ankle instability

PubMed Central

Kim, Ki-Jong; Heo, Myoung

2015-01-01

[Purpose] The aim of present study was to identify the impact that recent virtual reality training programs used in a variety of fields have had on the ankle’s static and dynamic senses of balance among subjects with functional ankle instability. [Subjects and Methods] This study randomly divided research subjects into two groups, a strengthening exercise group (Group I) and a balance exercise group (Group II), with each group consisting of 10 people. A virtual reality program was performed three times a week for four weeks. Exercises from the Nintendo Wii Fit Plus program were applied to each group for twenty minutes along with ten minutes of warming up and wrap-up exercises. [Results] Group II showed a significant decrease of post-intervention static and dynamic balance overall in the anterior-posterior, and mediolateral directions, compared with the pre-intervention test results. In comparison of post-intervention static and dynamic balance between Group I and Group II, a significant decrease was observed overall. [Conclusion] Virtual reality programs improved the static balance and dynamic balance of subjects with functional ankle instability. Virtual reality programs can be used more safely and efficiently if they are implemented under appropriate monitoring by a physiotherapist. PMID:26644652

Effects of virtual reality programs on balance in functional ankle instability.

PubMed

Kim, Ki-Jong; Heo, Myoung

2015-10-01

[Purpose] The aim of present study was to identify the impact that recent virtual reality training programs used in a variety of fields have had on the ankle's static and dynamic senses of balance among subjects with functional ankle instability. [Subjects and Methods] This study randomly divided research subjects into two groups, a strengthening exercise group (Group I) and a balance exercise group (Group II), with each group consisting of 10 people. A virtual reality program was performed three times a week for four weeks. Exercises from the Nintendo Wii Fit Plus program were applied to each group for twenty minutes along with ten minutes of warming up and wrap-up exercises. [Results] Group II showed a significant decrease of post-intervention static and dynamic balance overall in the anterior-posterior, and mediolateral directions, compared with the pre-intervention test results. In comparison of post-intervention static and dynamic balance between Group I and Group II, a significant decrease was observed overall. [Conclusion] Virtual reality programs improved the static balance and dynamic balance of subjects with functional ankle instability. Virtual reality programs can be used more safely and efficiently if they are implemented under appropriate monitoring by a physiotherapist.

Understanding the Influence of Organizational Culture and Group Dynamics on Organizational Change and Learning

ERIC Educational Resources Information Center

Lucas, Colleen; Kline, Theresa

2008-01-01

Purpose: The purpose of this study is to investigate the relationship between organizational culture, group dynamics, and organizational learning in the context of organizational change. Design/methodology/approach: A case study was used to examine cultural and group level factors that potentially influence groups' learning in the context of…

The Dynamics of the Local Group in the Era of Precision Astrometry

NASA Astrophysics Data System (ADS)

Besla, Gurtina; Garavito-Camargo, Nicolas; Patel, Ekta

2018-06-01

Our understanding of the dynamics of our Local Group of galaxies has changed dramatically over the past few years owing to significant advancements in astrometry and our theoretical understanding of galaxy structure. New surveys now enable us to map the 3D structure of our Milky Way and the dynamics of tracers of its dark matter distribution, like globular clusters, satellite galaxies and streams, with unprecedented precision. Some results have met with controversy, challenging preconceived notions of the orbital dynamics of key components of the Local Group. I will provide an overview of this evolving picture of our Local Group and outline how we can test the cold dark matter paradigm in the era of Gaia, LSST and JWST.

Virtual Habitat -a Dynamic Simulation of Closed Life Support Systems -Overall Status and Outlook

NASA Astrophysics Data System (ADS)

Zhukov, Anton; Schnaitmann, Jonas; Mecsaci, Ahmad; Bickel, Thomas; Markus Czupalla, M. Sc.

In order to optimize Life Support Systems (LSS) on a system level, stability questions and closure grade must be investigated. To do so the exploration group of the Technical University of Munich (TUM) is developing the "Virtual Habitat" (V-HAB) dynamic LSS simulation software. The main advantages of the dynamic simulation of LSS within V-HAB are the possibilities to compose different LSS configurations from the LSS subsystems and conduct dynamic simulation of it to test its stability in different mission scenarios inclusive emergency events and define the closure grade of the LSS. Additional the optimization of LSS based on different criteria will be possible. The Virtual Habitat simulation tool consists of four main modules: • Closed Environment Module (CEM) -monitoring of compounds in a closed environment • Crew Module (CM) -dynamic human simulation • P/C Systems Module (PCSM) -dynamic P/C subsystems • Plant Module (PM) -dynamic plant simulation Since the first idea and version, the V-HAB simulation has been significantly updated increasing its capabilities and maturity significantly. The updates which shall be introduced concern all modules of V-HAB. In particular: Significant progress has been made in development of the human model. In addition to the exist-ing human sub-models three newly developed ones (thermal regulation, digestion and schedule controller) have been introduced and shall be presented. Regarding the Plant Module a wheat plant model has been integrated in the V-HAB and is being correlated against test data. Ad-ditionally a first version of the algae bioreactor model has been developed and integrated. In terms of the P/C System module, an innovative approach for the P/C subsystem modelling has been developed and applied. The capabilities and features of the improved V-HAB models and the overall functionality of the V-HAB are demonstrated in form of meaningful test cases. In addition to the presentation of the results, the correlation strategy for the Virtual Habitat simulation shall be introduced assessing the models current confidence level and giving an outlook on the future correlation strategy.

OAST Space Theme Workshop. Volume 3: Working group summary. 9: Aerothermodynamics (M-3). A: Statement. B: Technology needs (form 1). C. Priority assessment (form 2). D. Additional assessments

NASA Technical Reports Server (NTRS)

1976-01-01

Twelve aerothermodynamic space technology needs were identified to reduce the design uncertainties in aerodynamic heating and forces experienced by heavy lift launch vehicles, orbit transfer vehicles, and advanced single stage to orbit vehicles for the space transportation system, and for probes, planetary surface landers, and sample return vehicles for solar system exploration vehicles. Research and technology needs identified include: (1) increasing the fluid dynamics capability by at least two orders of magnitude by developing an advanced computer processor for the solution of fluid dynamic problems with improved software; (2) predicting multi-engine base flow fields for launch vehicles; and (3) developing methods to conserve energy in aerothermodynamic ground test facilities.

[Interactive dynamic scalp acupuncture combined with occupational therapy for upper limb motor impairment in stroke: a randomized controlled trial].

PubMed

Wang, Jun; Pei, Jian; Cui, Xiao; Sun, Kexing; Ni, Huanhuan; Zhou, Cuixia; Wu, Ji; Huang, Mei; Ji, Li

2015-10-01

To compare the clinical efficacy on upper limb motor impairment in stroke between the interactive dynamic scalp acupuncture therapy and the traditional scalp acupuncture therapy. The randomized controlled trial and MINIMIZE layering randomization software were adopted. Seventy patients of upper limb with III to V grade in Brunnstrom scale after stroke were randomized into an interactive dynamic scalp acupuncture group and a traditional scalp acupuncture group, 35 cases in each one. In the interactive dynamic scalp acupuncture group, the middle 2/5 of Dingnieqianxiexian (anterior oblique line of vertex-temporal), the middle 2/5 of Dingniehouxiexian (posterior oblique line of vertex-temporal) and Dingpangerxian (lateral line 2 of vertex) on the affected side were selected as the stimulation areas. Additionally, the rehabilitation training was applied during scalp acupuncture treatment. In the traditional scalp acupuncture group, the scalp stimulation areas were same as the interactive dynamic scalp acupuncture group. But the rehabilitation training was applied separately. The rehabilitation training was applied in the morning and the scalp acupuncture was done in the afternoon. The results in Fugl-Meyer for the upper limb motor function (U-FMA), the Wolf motor function measure scale (WM- FT) and the modified Barthel index in the two groups were compared between the two groups before treatment and in 1 and 2 months of treatment, respectively. After treatment, the U-FMA score, WMFT score and the score of the modified Barthel index were all apparently improved as compared with those before treatment (all P < 0.01). The improvement in the U-FMA score after treatment in the interactive dynamic scalp acupuncture group was better than that in the traditional scalp acupuncture group (P < 0.05). For the patients of IV to V grade in Brunnstrom scale, WMFT score in 2 months of treatment and the score of Barthel index after treatment in the interactive dynamic scalp acupuncture group were improved apparently as compared with those in the traditional scalp acupuncture group (P < 0.05, P < 0.01). But, for the patients of III grade in Brunnstrom scale, WMFT score and the score of Barthel index after treatment in the interactive dynamic scalp acupuncture group were not different significantly as compared with those in the traditional scalp acupuncture group (both P > 0.05). For the patients of IV to V grade in Brunnstrom scale in stroke, the interactive dynamic scalp acupuncture therapy achieves the superior improvements of the upper limb motor function and the activity of daily life as compared with the traditional scalp acupuncture therapy, and the longer the treatment lasts, the more apparent the improvements are. For the patients of III grade in Brunnstrom scale, the interactive dynamic scalp acupuncture therapy achieves the similar improvement in the upper limb motor impairment as compared with the traditional scalp acupuncture therapy.

Developing stochastic epidemiological models to quantify the dynamics of infectious diseases in domestic livestock.

PubMed

MacKenzie, K; Bishop, S C

2001-08-01

A stochastic model describing disease transmission dynamics for a microparasitic infection in a structured domestic animal population is developed and applied to hypothetical epidemics on a pig farm. Rational decision making regarding appropriate control strategies for infectious diseases in domestic livestock requires an understanding of the disease dynamics and risk profiles for different groups of animals. This is best achieved by means of stochastic epidemic models. Methodologies are presented for 1) estimating the probability of an epidemic, given the presence of an infected animal, whether this epidemic is major (requires intervention) or minor (dies out without intervention), and how the location of the infected animal on the farm influences the epidemic probabilities; 2) estimating the basic reproductive ratio, R0 (i.e., the expected number of secondary cases on the introduction of a single infected animal) and the variability of the estimate of this parameter; and 3) estimating the total proportion of animals infected during an epidemic and the total proportion infected at any point in time. The model can be used for assessing impact of altering farm structure on disease dynamics, as well as disease control strategies, including altering farm structure, vaccination, culling, and genetic selection.

The allosteric communication pathways in KIX domain of CBP.

PubMed

Palazzesi, Ferruccio; Barducci, Alessandro; Tollinger, Martin; Parrinello, Michele

2013-08-27

Allosteric regulation plays an important role in a myriad of biomacromolecular processes. Specifically, in a protein, the process of allostery refers to the transmission of a local perturbation, such as ligand binding, to a distant site. Decades after the discovery of this phenomenon, models built on static images of proteins are being reconsidered with the knowledge that protein dynamics plays an important role in its function. Molecular dynamics simulations are a valuable tool for studying complex biomolecular systems, providing an atomistic description of their structure and dynamics. Unfortunately, their predictive power has been limited by the complexity of the biomolecule free-energy surface and by the length of the allosteric timescale (in the order of milliseconds). In this work, we are able to probe the origins of the allosteric changes that transcription factor mixed lineage leukemia (MLL) causes to the interactions of KIX domain of CREB-binding protein (CBP) with phosphorylated kinase inducible domain (pKID), by combing all-atom molecular dynamics with enhanced sampling methods recently developed in our group. We discuss our results in relation to previous NMR studies. We also develop a general simulations protocol to study allosteric phenomena and many other biological processes that occur in the micro/milliseconds timescale.

Development of renormalization group analysis of turbulence

NASA Technical Reports Server (NTRS)

Smith, L. M.

1990-01-01

The renormalization group (RG) procedure for nonlinear, dissipative systems is now quite standard, and its applications to the problem of hydrodynamic turbulence are becoming well known. In summary, the RG method isolates self similar behavior and provides a systematic procedure to describe scale invariant dynamics in terms of large scale variables only. The parameterization of the small scales in a self consistent manner has important implications for sub-grid modeling. This paper develops the homogeneous, isotropic turbulence and addresses the meaning and consequence of epsilon-expansion. The theory is then extended to include a weak mean flow and application of the RG method to a sequence of models is shown to converge to the Navier-Stokes equations.

Metastable structures and size effects in small group dynamics

PubMed Central

Lauro Grotto, Rosapia; Guazzini, Andrea; Bagnoli, Franco

2014-01-01

In his seminal works on group dynamics Bion defined a specific therapeutic setting allowing psychoanalytic observations on group phenomena. In describing the setting he proposed that the group was where his voice arrived. This physical limit was later made operative by assuming that the natural dimension of a therapeutic group is around 12 people. Bion introduced a theory of the group aspects of the mind in which proto-mental individual states spontaneously evolve into shared psychological states that are characterized by a series of features: (1) they emerge as a consequence of the natural tendency of (both conscious and unconscious) emotions to combine into structured group patterns; (2) they have a certain degree of stability in time; (3) they tend to alternate so that the dissolution of one is rapidly followed by the emergence of another; (4) they can be described in qualitative terms according to the nature of the emotional mix that dominates the state, in structural terms by a kind of typical “leadership” pattern, and in “cognitive” terms by a set of implicit expectations that are helpful in explaining the group behavior (i.e., the group behaves “as if” it was assuming that). Here we adopt a formal approach derived from Socio-physics in order to explore some of the structural and dynamic properties of this small group dynamics. We will described data from an analytic DS model simulating small group interactions of agents endowed with a very simplified emotional and cognitive dynamic in order to assess the following main points: (1) are metastable collective states allowed to emerge in the model and if so, under which conditions in the parameter space? (2) can these states be differentiated in structural terms? (3) to what extent are the emergent dynamic features of the systems dependent of the system size? We will finally discuss possible future applications of the quantitative descriptions of the interaction structure in the small group clinical setting. PMID:25071665

Effect of Cognitive Demand on Functional Visual Field Performance in Senior Drivers with Glaucoma.

PubMed

Gangeddula, Viswa; Ranchet, Maud; Akinwuntan, Abiodun E; Bollinger, Kathryn; Devos, Hannes

2017-01-01

Purpose: To investigate the effect of cognitive demand on functional visual field performance in drivers with glaucoma. Method: This study included 20 drivers with open-angle glaucoma and 13 age- and sex-matched controls. Visual field performance was evaluated under different degrees of cognitive demand: a static visual field condition (C1), dynamic visual field condition (C2), and dynamic visual field condition with active driving (C3) using an interactive, desktop driving simulator. The number of correct responses (accuracy) and response times on the visual field task were compared between groups and between conditions using Kruskal-Wallis tests. General linear models were employed to compare cognitive workload, recorded in real-time through pupillometry, between groups and conditions. Results: Adding cognitive demand (C2 and C3) to the static visual field test (C1) adversely affected accuracy and response times, in both groups ( p < 0.05). However, drivers with glaucoma performed worse than did control drivers when the static condition changed to a dynamic condition [C2 vs. C1 accuracy; glaucoma: median difference (Q1-Q3) 3 (2-6.50) vs. 2 (0.50-2.50); p = 0.05] and to a dynamic condition with active driving [C3 vs. C1 accuracy; glaucoma: 2 (2-6) vs. 1 (0.50-2); p = 0.02]. Overall, drivers with glaucoma exhibited greater cognitive workload than controls ( p = 0.02). Conclusion: Cognitive demand disproportionately affects functional visual field performance in drivers with glaucoma. Our results may inform the development of a performance-based visual field test for drivers with glaucoma.

Comparison of the effects on dynamic balance and aerobic capacity between objective and subjective methods of high-intensity robot-assisted gait training in chronic stroke patients: a randomized controlled trial.

PubMed

Bae, Young-Hyeon; Lee, Suk Min; Ko, Mansoo

2017-05-01

Robot-assisted gait training (RAGT) is effective for improving dynamic balance and aerobic capacity, but previous RAGT method does not set suitable training intensity. Recently, high-intensity treadmill gait training at 70% of heart rate reserve (HRR) was used for improving aerobic capacity and dynamic balance. This study was designed to compare the effectiveness between objective and subjective methods of high-intensity RAGT for improving dynamic balance and aerobic capacity in chronic stroke. Subjects were randomly allocated into experimental (n = 17) and control (n = 17) groups. The experimental group underwent high-intensity RAGT at 70% of HRR, whereas the control group underwent high-intensity RAGT at an RPE of 15. Both groups received their assigned training for 30 min per session, 3 days per week for 6 weeks. All subjects also received an additional 30 min of conventional physical therapy. Before and after each of the 18 sessions, the dynamic balance and aerobic capacity of all subjects were evaluated by a blinded examiner. After training, Berg Balance Scale (BBS) and Timed Up and Go Test scores, VO 2 max, and VO 2 max/kg were significantly increased in both groups (p < 0.05). These variables in experimental group were significantly greater than control group. However, the BBS score was not significantly different between both groups. All subjects completed high-intensity RAGT. No adverse effect of training was observed in both groups. High-intensity RAGT at 70% of HRR significantly improved dynamic balance and aerobic capacity more than RAGT at RPE of 15. These results suggest that high-intensity RAGT at 70% of HRR is safe and effective for improving dynamic balance and aerobic capacity in chronic stroke.

Training Vocational Rehabilitation Counselors in Group Dynamics: A Psychoeducational Model.

ERIC Educational Resources Information Center

Elliott, Timothy R.

1990-01-01

Describes a six-session psychoeducational program for training vocational rehabilitation counselors in group dynamics. Presents evaluation of program by counselors (N=15) in which leadership styles, conflict management, and typology of group tasks concepts were rated as most beneficial. (Author/ABL)

Effects of One-Week Empirical Antibiotic Therapy on the Early Development of Gut Microbiota and Metabolites in Preterm Infants.

PubMed

Zhu, Danping; Xiao, Sa; Yu, Jialin; Ai, Qing; He, Yu; Cheng, Chen; Zhang, Yunhui; Pan, Yun

2017-08-14

The early postnatal period is the most dynamic and vulnerable stage in the assembly of intestinal microbiota. Antibiotics are commonly prescribed to newborn preterm babies and are frequently used for a prolonged duration in China. We hypothesized that the prolonged antibiotic therapy would affect the early development of intestinal microbiota and their metabolites. To test this hypothesis, we analyzed the stool microbiota and metabolites in 36 preterm babies with or without antibiotic treatment. These babies were divided into three groups, including two groups treated with the combination of penicillin and moxalactam or piperacillin-tazobactam for 7 days, and the other group was free of antibiotics. Compared to the antibiotic-free group, both antibiotic-treated groups had distinct gut microbial communities and metabolites, including a reduction of bacterial diversity and an enrichment of harmful bacteria such as Streptococcus and Pseudomonas. In addition, there was a significant difference in the composition of gut microbiota and their metabolites between the two antibiotic-treated groups, where the piperacillin-tazobactam treatment group showed an overgrowth of Enterococcus. These findings suggest that prolonged antibiotic therapy affects the early development of gut microbiota in preterm infants, which should be considered when prescribing antibiotics for this population.

Live Imaging to Study Microtubule Dynamic Instability in Taxane-resistant Breast Cancers.

PubMed

Wang, Richard; Wang, Harris; Wang, Zhixiang

2017-02-20

Taxanes such as docetaxel belong to a group of microtubule-targeting agents (MTAs) that are commonly relied upon to treat cancer. However, taxane resistance in cancerous cells drastically reduces the effectiveness of the drugs' long-term usage. Accumulated evidence suggests that the mechanisms underlying taxane resistance include both general mechanisms, such as the development of multidrug resistance due to the overexpression of drug-efflux proteins, and taxane-specific mechanisms, such as those that involve microtubule dynamics. Because taxanes target cell microtubules, measuring microtubule dynamic instability is an important step in determining the mechanisms of taxane resistance and provides insight into how to overcome this resistance. In the experiment, an in vivo method was used to measure microtubule dynamic instability. GFP-tagged α-tubulin was expressed and incorporated into microtubules in MCF-7 cells, allowing for the recording of the microtubule dynamics by time lapse using a sensitive camera. The results showed that, as opposed to the non-resistant parental MCF-7CC cells, the microtubule dynamics of docetaxel-resistant MCF-7TXT cells are insensitive to docetaxel treatment, which causes the resistance to docetaxel-induced mitotic arrest and apoptosis. This paper will outline this in vivo method of measuring microtubule dynamic instability.

Perspectives of Community Co-Researchers About Group Dynamics and Equitable Partnership Within a Community-Academic Research Team.

PubMed

Vaughn, Lisa M; Jacquez, Farrah; Zhen-Duan, Jenny

2018-04-01

Equitable partnership processes and group dynamics, including individual, relational, and structural factors, have been identified as key ingredients to successful community-based participatory research partnerships. The purpose of this qualitative study was to investigate the key aspects of group dynamics and partnership from the perspectives of community members serving as co-researchers. Semistructured, in-depth interviews were conducted with 15 Latino immigrant co-researchers from an intervention project with Latinos Unidos por la Salud (LU-Salud), a community research team composed of Latino immigrant community members and academic investigators working in a health research partnership. A deductive framework approach guided the interview process and qualitative data analysis. The LU-Salud co-researchers described relationships, personal growth, beliefs/identity motivation (individual dynamics), coexistence (relational dynamics), diversity, and power/resource sharing (structural dynamics) as key foundational aspects of the community-academic partnership. Building on existing CBPR and team science frameworks, these findings demonstrate that group dynamics and partnership processes are fundamental drivers of individual-level motivation and meaning making, which ultimately sustain efforts of community partners to engage with the research team and also contribute to the achievement of intended research outcomes.

An electromyographic analysis of two handwriting grasp patterns.

PubMed

de Almeida, Pedro Henrique Tavares Queiroz; da Cruz, Daniel Marinho Cezar; Magna, Luis Alberto; Ferrigno, Iracema Serrat Vergotti

2013-08-01

Handwriting is a fundamental skill needed for the development of daily-life activities during lifetime and can be performed using different forms to hold the writing object. In this study, we monitored the sEMG activity of trapezius, biceps brachii, extensor carpi radialis brevis and flexor digitorum superficialis during a handwriting task with two groups of subjects using different grasp patterns. Twenty-four university students (thirteen males and eleven females; mean age of 22.04±2.8years) were included in this study. We randomly invited 12 subjects that used the Dynamic Tripod grasp and 12 subjects that used the Static Tripod grasp. The static tripod group showed statistically significant changes in the sEMG activity of trapezium and biceps brachii muscles during handwriting when compared to dynamic tripod group's subjects. No significant differences were found in extensor carpi radialis brevis and flexor digitorum superficialis activities among the two groups. The findings in this study suggest an increased activity of proximal muscles among subjects using a transitional grasp, indicating potential higher energy expenditure and muscular harm with the maintenance of this motor pattern in handwriting tasks, especially during the progression in academic life. Copyright © 2013 Elsevier Ltd. All rights reserved.

Therapeutic Change in Group Therapy For Interpersonal Trauma: A Relational Framework for Research and Clinical Practice.

PubMed

Chouliara, Zoë; Karatzias, Thanos; Gullone, Angela; Ferguson, Sandra; Cosgrove, Katie; Burke Draucker, Claire

2017-04-01

Our understanding of therapeutic change processes in group therapy for complex interpersonal trauma has been limited. The present study aimed at addressing this gap by developing a framework of therapeutic change in this field from a survivor and therapist perspective. This is a qualitative study, which utilized semistructured individual interviews. Transcripts were analyzed using interpretative phenomenological analysis (IPA) to identify recurrent themes. A final sample of n = 16 patients and n = 5 facilitators completed the interview. Main change processes identified by survivors were as follows: self versus others, trust versus threat, confrontation versus avoidance, and "patching up" versus true healing. Therapeutic processes identified by therapist facilitators included managing group dynamics, unpredictability and uncertainty, and process versus content. The proposed framework explains therapeutic change in group therapy in relational terms, that is, therapeutic dissonance, the dynamic interaction of self and experience as well as building empathic trusting relations. The importance of managing dissonance to aid personally meaningful recovery was highlighted. These findings have implications for the usefulness of relational and person-centered approaches to clinical practice in the area of interpersonal and complex trauma, especially in the early identification, prevention, and management of dropouts.

Computations involving differential operators and their actions on functions

NASA Technical Reports Server (NTRS)

Crouch, Peter E.; Grossman, Robert; Larson, Richard

1991-01-01

The algorithms derived by Grossmann and Larson (1989) are further developed for rewriting expressions involving differential operators. The differential operators involved arise in the local analysis of nonlinear dynamical systems. These algorithms are extended in two different directions: the algorithms are generalized so that they apply to differential operators on groups and the data structures and algorithms are developed to compute symbolically the action of differential operators on functions. Both of these generalizations are needed for applications.

Comparison of dynamic balance ability in healthy university students according to foot shape.

PubMed

Hyong, In Hyouk; Kang, Jong Ho

2016-01-01

[Purpose] This study aimed to compare dynamic balance ability according to foot shape, defined as normal, pronated, or supinated on the basis of the height of the medial arch. [Subjects] In this study, 14 subjects for the pronated foot group, 14 for the supinated foot group, and 14 for the normal foot group were selected from among 162 healthy university students by using the navicular drop test proposed by Brody. To measure dynamic balance ability, a star excursion balance test (SEBT) was conducted for each group, in which a cross-shaped line and lines at 45° in eight directions were drawn on the floor. In this study, only three directions were used, namely anterior, posterolateral, and posteromedial. The mean of the SEBT was calculated by measuring three times for each group, and the values were standardized using the following equation: measured value/leg length × 100. [Results] No significant differences in dynamic balance ability were found between the normal, pronated, and supinated foot groups. [Conclusion] No significant differences in dynamic balance ability according to the foot shape were found among the healthy university students with normal, pronated, and supinated feet.

Supramolecular Systems Behavior at the Air-Water Interface. Molecular Dynamic Simulation Study.

NASA Astrophysics Data System (ADS)

Sandoval, C.; Saavedra, M.; Gargallo, L.; Radić, D.

2008-08-01

Atomistic molecular dynamics simulation (MDS) was development to investigate the structural and dynamic properties of a monolayer of supramolecular systems. The simulations were performed at room temperature, on inclusion complexes (ICs) of α-cyclodextrin (CD) with poly(ethylene-oxide)(PEO), poly(ɛ-caprolactone)(PEC) and poly(tetrahydrofuran)(PTHF). The simulations were carried out for a surface area of 30Å. The trajectories of the MDS show that the system more stable was IC-PEC, being the less stable IC-PEO. The disordered monolayer for the systems was proved by the orientation correlation function and the radial distribution function between the polar groups of ICs and the water molecules. We found that the system IC-PEC was more stable that the systems IC-PTHF and IC-PEO.

BoD services in layer 1 VPN with dynamic virtual concatenation group

NASA Astrophysics Data System (ADS)

Du, Shu; Peng, Yunfeng; Long, Keping

2008-11-01

Bandwidth-on-Demand (BoD) services are characteristic of dynamic bandwidth provisioning based on customers' resource requirement, which will be a must for future networks. BoD services become possible with the development of make-before-break, Virtual Concatenation (VCAT) and Link Capacity Adjustment Scheme (LCAS). In this paper, we introduce BoD services into L1VPN, thus the resource assigned to a L1VPN can be gracefully adjusted at various bandwidth granularities based on customers' requirement. And we propose a dynamic bandwidth adjustment scheme, which is compromise between make-before-break and VCAT&LCAS and mainly based on the latter. The scheme minimizes the number of distinct paths to support a connection between a source-destination pair, and uses make-beforebreak technology for re-optimization.

Beyond the banality of evil: three dynamics of an interactionist social psychology of tyranny.

PubMed

Haslam, S Alexander; Reicher, Stephen

2007-05-01

Carnahan and McFarland critique the situationist account of the Stanford prison experiment by arguing that understanding extreme action requires consideration of individual characteristics and the interaction between person and situation. Haslam and Reicher develop this argument in two ways. First, they reappraise historical and psychological evidence that supports the broader "banality of evil" thesis-the idea that ordinary people commit atrocities without awareness, care, or choice. Counter to this thesis, they show that perpetrators act thoughtfully, creatively, and with conviction. Second, drawing from this evidence and the BBC [British Broadcasting Corporation] Prison Study, they make the case for an interactionist approach to tyranny that explains how people are (a) initially drawn to extreme and oppressive groups, (b) transformed by membership in those groups, and (c) able to gain influence over others and hence normalize oppression. These dynamics can make evil appear banal but are far from banal themselves.

Simulations of moving effect of coastal vegetation on tsunami damping

NASA Astrophysics Data System (ADS)

Tsai, Ching-Piao; Chen, Ying-Chi; Octaviani Sihombing, Tri; Lin, Chang

2017-05-01

A coupled wave-vegetation simulation is presented for the moving effect of the coastal vegetation on tsunami wave height damping. The problem is idealized by solitary wave propagation on a group of emergent cylinders. The numerical model is based on general Reynolds-averaged Navier-Stokes equations with renormalization group turbulent closure model by using volume of fluid technique. The general moving object (GMO) model developed in computational fluid dynamics (CFD) code Flow-3D is applied to simulate the coupled motion of vegetation with wave dynamically. The damping of wave height and the turbulent kinetic energy along moving and stationary cylinders are discussed. The simulated results show that the damping of wave height and the turbulent kinetic energy by the moving cylinders are clearly less than by the stationary cylinders. The result implies that the wave decay by the coastal vegetation may be overestimated if the vegetation was represented as stationary state.

The Renormalization Group and Its Applications to Generating Coarse-Grained Models of Large Biological Molecular Systems.

PubMed

Koehl, Patrice; Poitevin, Frédéric; Navaza, Rafael; Delarue, Marc

2017-03-14

Understanding the dynamics of biomolecules is the key to understanding their biological activities. Computational methods ranging from all-atom molecular dynamics simulations to coarse-grained normal-mode analyses based on simplified elastic networks provide a general framework to studying these dynamics. Despite recent successes in studying very large systems with up to a 100,000,000 atoms, those methods are currently limited to studying small- to medium-sized molecular systems due to computational limitations. One solution to circumvent these limitations is to reduce the size of the system under study. In this paper, we argue that coarse-graining, the standard approach to such size reduction, must define a hierarchy of models of decreasing sizes that are consistent with each other, i.e., that each model contains the information of the dynamics of its predecessor. We propose a new method, Decimate, for generating such a hierarchy within the context of elastic networks for normal-mode analysis. This method is based on the concept of the renormalization group developed in statistical physics. We highlight the details of its implementation, with a special focus on its scalability to large systems of up to millions of atoms. We illustrate its application on two large systems, the capsid of a virus and the ribosome translation complex. We show that highly decimated representations of those systems, containing down to 1% of their original number of atoms, still capture qualitatively and quantitatively their dynamics. Decimate is available as an OpenSource resource.

Total Quality Management (TQM): Group Dynamics Workshop

DTIC Science & Technology

1990-05-15

interactions with other OSD decision-making bodies. " Remove barriers /facilitate implementation. " Direct action on unresolved process problems referred...TQM leadership. - Total Quality Management FUNCTIONS: * Translate goals to tangible internal initiatives. " Remove barriers . " Establish and...Quality Management FUNCTIONS: • Identify and remove barriers . " Develop practical process improvements. " Install solutions and measurement systems for

Overcoming Unintentional Barriers with Intentional Strategies: Educating Faculty about Student Disabilities

ERIC Educational Resources Information Center

Forrest, Krista D.

2003-01-01

Krista Forrest is an Assistant Professor in the Department of Psychology at the University of Nebraska at Kearney, where she teaches general psychology and life span development as well as advanced courses in adolescent psychology, group dynamics, and psychology and law. A graduate of North Carolina State University with a MS in developmental…

Children's Gender Identity Development: The Dynamic Negotiation Process between Conformity and Authenticity

ERIC Educational Resources Information Center

Brinkman, Britney G; Rabenstein, Kelly L.; Rosén, Lee A.; Zimmerman, Toni S.

2014-01-01

In the current study, 45 girls and 41 boys participated in focus groups following a program designed to teach them about social justice. The children articulated the discrepancy between their own gender identity and gender role stereotypes and discussed potential problems with conforming to gender role expectations as well as consequences of…

An Evaluation of Career Selection Education in Thirteen Project Schools of the Western States Small Schools Project.

ERIC Educational Resources Information Center

Cragun, John R.; Kartchner, Eugene C.

The Western States Small Schools Project (WSSSP) developed the Career Selection Education (CSE) program to provide students from small high schools in Arizona, Colorado, Nevada, New Mexico, and Utah with: (1) knowledge about self, broad occupational groupings, the institution and dynamics of society which generate, define, and lend meaning to…

Fire Process Research Natural Areas: Managing research and restoration of dynamic ecosystem processes

Treesearch

Timothy Ingalsbee

2001-01-01

Since 1992 a collaborative group of fire scientists, forest conservationists, and Federal resource specialists have been developing proposals for a Research Natural Area (RNA) in the Warner Creek Fire area on the Willamette National Forest in Oregon. Inspired by these proposals, the Oregon Natural Heritage Plan created the new category of "Fire Process RNAs"...

Handwriting Development in Spanish Children with and without Learning Disabilities: A Graphonomic Approach

ERIC Educational Resources Information Center

Barrientos, Pablo

2017-01-01

The central purpose of this study was to analyze the dynamics of handwriting movements in real time for Spanish students in early grades with and without learning disabilities. The sample consisted of 120 children from Grades 1 through 3 (primary education), classified into two groups: with learning disabilities and without learning disabilities.…

From Faculty for Undergraduate Neuroscience: Encouraging Innovation in Undergraduate Neuroscience Education by Supporting Student Research and Faculty Development

ERIC Educational Resources Information Center

Hardwick, Jean C.; Kerchner, Michael; Lom, Barbara; Ramirez, Julio J.; Wiertelak, Eric P.

2006-01-01

This article features the organization Faculty for Undergraduate Neuroscience. FUN was established by a group of neuroscientists dedicated to innovation and excellence in undergraduate neuroscience education and research. In the years since its inception, FUN has grown into a dynamic organization making a significant impact on the quality of…

Numerical Study on Stress Heterogeneity Development in Two-Phase Rocks with Large Rheological Contrast and Implications in the Lower Crust

NASA Astrophysics Data System (ADS)

Xu, Junshan; Zhang, Baohua

2018-03-01

Development of stress heterogeneity in two-phase rocks was investigated via a finite element method at 1000-1200 K and 100 MPa. Two groups of rock models were considered: anorthite-diopside and anorthite-clinopyroxene, with a phase volume ratio of 1:1 in each group and different dislocation creep rates between phases ( 4-8 orders of magnitude). Our numerical results indicate that the stress inside the model can be several times higher than the differential stress applied to the model and stress will tend to concentrate in hard phase, especially near the sharp boundaries with soft phase. Moreover, large stress gradient in hard phase and nearly homogeneous stress in soft phase will lead to the initialization of localized dynamic recrystallization or fracture. These numerical observations suggest that the rheological contrast between two phases plays a crucial role in stress heterogeneity rather than other factors (such as grain size, the boundary conditions or mesh density), which may eventually accelerate development of stress heterogeneity in the lower crust. Our study provides new insights into the dynamic processes of grain size reduction in the lower crust, which may cause the transformation from dislocation creep to diffusion creep and enable the weakened shear zones.

Group implicit concurrent algorithms in nonlinear structural dynamics

NASA Technical Reports Server (NTRS)

Ortiz, M.; Sotelino, E. D.

1989-01-01

During the 70's and 80's, considerable effort was devoted to developing efficient and reliable time stepping procedures for transient structural analysis. Mathematically, the equations governing this type of problems are generally stiff, i.e., they exhibit a wide spectrum in the linear range. The algorithms best suited to this type of applications are those which accurately integrate the low frequency content of the response without necessitating the resolution of the high frequency modes. This means that the algorithms must be unconditionally stable, which in turn rules out explicit integration. The most exciting possibility in the algorithms development area in recent years has been the advent of parallel computers with multiprocessing capabilities. So, this work is mainly concerned with the development of parallel algorithms in the area of structural dynamics. A primary objective is to devise unconditionally stable and accurate time stepping procedures which lend themselves to an efficient implementation in concurrent machines. Some features of the new computer architecture are summarized. A brief survey of current efforts in the area is presented. A new class of concurrent procedures, or Group Implicit algorithms is introduced and analyzed. The numerical simulation shows that GI algorithms hold considerable promise for application in coarse grain as well as medium grain parallel computers.

Land-Price Dynamics Surrounding Large-Scale Land Development of Technopolis Gedebage, Bandung, Indonesia

NASA Astrophysics Data System (ADS)

Hasanawi, A.; Winarso, H.

2018-05-01

In spite of its potential value to governments, detailed information on how land prices vary spatially in a city is very lacking. Land price in the city, especially around the development activity, is not known. There are some considerable studies showing that investment in land development increases the land market price; however, only a few are found. One of them is about the impact of large-scale investment by Sumarecon in Gedebage Bandung, which is planning to develop “Technopolis”, as the second center of Bandung Municipality.This paper discusses the land-price dynamics around the Technopolis Gedebage Bandung, using information obtained from many sources including an interview with experienced brokers. Appraised prices were given for different types of residential plot distinguished by tenure, distance from the main road, and infrastructural provision. This research aims to explain the dynamics of the land price surrounding the large-scale land development. The dynamics of the land price are described by the median land price market growth using the Surfer DEM software. The data analysis in Technopolis Gedebage Bandung shows the relative importance of land location, infrastructural provision and tenure (land title) for dynamics of the land price. The examination of data makes it possible to test whether and where there has been a spiraling of land prices. This paper argues that the increasing recent price has been consistently greater in suburban plots than that in the inner city as a result of the massive demand of the large-scale land development project. The increasing price of land cannot be controlled; the market price is rising very quickly among other things due to the fact that Gedebage will become the technopolis area. This, however, can indirectly burden the lower-middle-class groups, such as they are displaced from their previous owned-land, and implicate on ever-decreasing income as the livelihood resources (such as farming and agriculture) are lost.

A Complex Systems Investigation of Group Work Dynamics in L2 Interactive Tasks

ERIC Educational Resources Information Center

Poupore, Glen

2018-01-01

Working with Korean university-level learners of English, this study provides a detailed analytical comparison of 2 task work groups that were video-recorded, with 1 group scoring very high and the other relatively low based on the results of a Group Work Dynamic (GWD) measuring instrument. Adopting a complexity theory (CT) perspective and…

Explaining Dynamic Interactions in Wiki-Based Collaborative Writing

ERIC Educational Resources Information Center

Li, Mimi; Zhu, Wei

2017-01-01

This article reports a case study that examined dynamic patterns of interaction that two small groups (Group A and Group B) of ESL students exemplified when they performed two writing tasks: a research proposal (Task 1) and an annotated bibliography (Task 2) in a wiki site. Group A demonstrated a collective pattern in Task 1, but switched to an…

Development of Fracture Mechanics Maps for Composite Materials. Volume 2.

DTIC Science & Technology

1985-12-01

AD-A169 663 DEP 1/3UR OIOST l uNCL~ss~~n HUCI S I B M 11 1*2 AF,:P,.-TR-?5,-4150 DEVELOPMENT OF FRACTURE MECHANICS MAPS FOR COMPOSITE MATERIALS Dr. H...coIo. Development of N/A N/A N/A N/A Fracture Mechanics Maps for Composite Materials 12. PERSONAL AUTHORISI Editor (Dr. H. W. Bergmann) 13. TYPE OF...GROUP SUB GR. Fiber Reinforced Composites , Dynamic Test, Thermal Cycling, 1I1 04 Quality Control, Static Test, Stress Concentrations 01 03 19

Lunar settlements - A socio-economic outlook

NASA Technical Reports Server (NTRS)

Bluth, B. J.

1986-01-01

Factors in the design and development of a lunar settlement (LS) which affect the performance of the crew members are discussed. Topics examined include LS-program time constraints imposed by decisions made in developing and operating the Space Station; changes to make allowance for the long-term requirements of LSs; the design of the physical, technical, and organic LS environment; and the vital role of group dynamics in assuring LS success. It is suggested that many short-term cost-minimization strategies employed in spacecraft development may be inappropriate for LS programs.

Rotation of Guanine Amino Groups in G-Quadruplexes: A Probe for Local Structure and Ligand Binding.

PubMed

Adrian, Michael; Winnerdy, Fernaldo Richtia; Heddi, Brahim; Phan, Anh Tuân

2017-08-22

Nucleic acids are dynamic molecules whose functions may depend on their conformational fluctuations and local motions. In particular, amino groups are dynamic components of nucleic acids that participate in the formation of various secondary structures such as G-quadruplexes. Here, we present a cost-efficient NMR method to quantify the rotational dynamics of guanine amino groups in G-quadruplex nucleic acids. An isolated spectrum of amino protons from a specific tetrad-bound guanine can be extracted from the nuclear Overhauser effect spectroscopy spectrum based on the close proximity between the intra-residue imino and amino protons. We apply the method in different structural contexts of G-quadruplexes and their complexes. Our results highlight the role of stacking and hydrogen-bond interactions in restraining amino-group rotation. The measurement of the rotation rate of individual amino groups could give insight into the dynamic processes occurring at specific locations within G-quadruplex nucleic acids, providing valuable probes for local structure, dynamics, and ligand binding. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Early ovarian follicular development in prepubertal Wistar rats acutely exposed to androgens.

PubMed

Paixão, L; Velez, L M; Santos, B R; Tusset, C; Lecke, S B; Motta, A B; Spritzer, P M

2016-08-01

Androgens may directly modulate early ovarian follicular development in preantral stages and androgen excess before puberty may disrupt this physiological process. Therefore, the aim of this study was to investigate the dynamics of follicular morphology and circulating androgen and estradiol levels in prepubertal Wistar rats acutely exposed to androgens. Prepubertal female Wistar rats were distributed into three groups: control, equine chorionic gonadotropin (eCG) intervention and eCG plus dehydroepiandrosterone (DHEA) intervention (eCG+DHEA). Serum DHEA, testosterone and estradiol levels were determined, and ovarian morphology and morphometry were assessed. The eCG+DHEA group presented increased serum estradiol and testosterone levels as compared with the control group (P<0.01), and higher serum DHEA concentration v. the eCG-only and control groups (P<0.01). In addition, the eCG+DHEA group had a higher number of, and larger-sized, primary and secondary follicles as compared with the control group (P<0.05). The eCG group presented intermediate values for number and size of primary and secondary follicles, without significant differences as compared with the other two groups. The number of antral follicles was higher in the eCG+DHEA and eCG groups v. controls (P<0.05). The number of primordial, atretic and cystic follicles were similar in all groups. In conclusion, the present experimental model using an acute eCG+DHEA intervention was useful to investigate events involved in initial follicular development under hyperandrogenic conditions, and could provide a reliable tool to study defective follicular development with possible deleterious reproductive consequences later in life.

Conformational Control of Ultrafast Molecular Rotor Property: Tuning Viscosity Sensing Efficiency by Twist Angle Variation.

PubMed

Ghosh, Rajib; Kushwaha, Archana; Das, Dipanwita

2017-09-21

Fluorescent molecular rotors find widespread application in sensing and imaging of microscopic viscosity in complex chemical and biological media. Development of viscosity-sensitive ultrafast molecular rotor (UMR) relies upon the understanding of the excited-state dynamics and their implications for viscosity-dependent fluorescence signaling. Unraveling the structure-property relationship of UMR behavior is of significance toward development of an ultrasensitive fluorescence microviscosity sensor. Herein we show that the ground-state equilibrium conformation has an important role in the ultrafast twisting dynamics of UMRs and consequent viscosity sensing efficiency. Synthesis, photophysics, and ultrafast spectroscopic experiments in conjunction with quantum chemical calculation of a series of UMRs based on dimethylaniline donor and benzimidazolium acceptor with predefined ground-state torsion angle led us to unravel that the ultrafast torsional dynamics around the bond connecting donor and acceptor groups profoundly influences the molecular rotor efficiency. This is the first experimental demonstration of conformational control of small-molecule-based UMR efficiencies which can have wider implication toward development of fluorescence sensors based on the UMR principle. Conformation-controlled UMR efficiency has been shown to exhibit commensurate fluorescence enhancement upon DNA binding.

A tool for exploring the dynamics of innovative interventions for public health: the critical event card.

PubMed

Figueiro, Ana Claudia; de Araújo Oliveira, Sydia Rosana; Hartz, Zulmira; Couturier, Yves; Bernier, Jocelyne; do Socorro Machado Freire, Maria; Samico, Isabella; Medina, Maria Guadalupe; de Sa, Ronice Franco; Potvin, Louise

2017-03-01

Public health interventions are increasingly represented as complex systems. Research tools for capturing the dynamic of interventions processes, however, are practically non-existent. This paper describes the development and proof of concept process of an analytical tool, the critical event card (CEC), which supports the representation and analysis of complex interventions' evolution, based on critical events. Drawing on the actor-network theory (ANT), we developed and field-tested the tool using three innovative health interventions in northeastern Brazil. Interventions were aimed to promote health equity through intersectoral approaches; were engaged in participatory evaluation and linked to professional training programs. The CEC developing involve practitioners and researchers from projects. Proof of concept was based on document analysis, face-to-face interviews and focus groups. Analytical categories from CEC allow identifying and describing critical events as milestones in the evolution of complex interventions. Categories are (1) event description; (2) actants (human and non-human) involved; (3) interactions between actants; (4) mediations performed; (5) actions performed; (6) inscriptions produced; and (7) consequences for interventions. The CEC provides a tool to analyze and represent intersectoral internvetions' complex and dynamic evolution.

Simulating Food Web Dynamics along a Gradient: Quantifying Human Influence

PubMed Central

Jordán, Ferenc; Gjata, Nerta; Mei, Shu; Yule, Catherine M.

2012-01-01

Realistically parameterized and dynamically simulated food-webs are useful tool to explore the importance of the functional diversity of ecosystems, and in particular relations between the dynamics of species and the whole community. We present a stochastic dynamical food web simulation for the Kelian River (Borneo). The food web was constructed for six different locations, arrayed along a gradient of increasing human perturbation (mostly resulting from gold mining activities) along the river. Along the river, the relative importance of grazers, filterers and shredders decreases with increasing disturbance downstream, while predators become more dominant in governing eco-dynamics. Human activity led to increased turbidity and sedimentation which adversely impacts primary productivity. Since the main difference between the study sites was not the composition of the food webs (structure is quite similar) but the strengths of interactions and the abundance of the trophic groups, a dynamical simulation approach seemed to be useful to better explain human influence. In the pristine river (study site 1), when comparing a structural version of our model with the dynamical model we found that structurally central groups such as omnivores and carnivores were not the most important ones dynamically. Instead, primary consumers such as invertebrate grazers and shredders generated a greater dynamical response. Based on the dynamically most important groups, bottom-up control is replaced by the predominant top-down control regime as distance downstream and human disturbance increased. An important finding, potentially explaining the poor structure to dynamics relationship, is that indirect effects are at least as important as direct ones during the simulations. We suggest that our approach and this simulation framework could serve systems-based conservation efforts. Quantitative indicators on the relative importance of trophic groups and the mechanistic modeling of eco-dynamics could greatly contribute to understanding various aspects of functional diversity. PMID:22768346

Effect of micromorphology of cortical bone tissue on crack propagation under dynamic loading

NASA Astrophysics Data System (ADS)

Wang, Mayao; Gao, Xing; Abdel-Wahab, Adel; Li, Simin; Zimmermann, Elizabeth A.; Riedel, Christoph; Busse, Björn; Silberschmidt, Vadim V.

2015-09-01

Structural integrity of bone tissue plays an important role in daily activities of humans. However, traumatic incidents such as sports injuries, collisions and falls can cause bone fracture, servere pain and mobility loss. In addition, ageing and degenerative bone diseases such as osteoporosis can increase the risk of fracture [1]. As a composite-like material, a cortical bone tissue is capable of tolerating moderate fracture/cracks without complete failure. The key to this is its heterogeneously distributed microstructural constituents providing both intrinsic and extrinsic toughening mechanisms. At micro-scale level, cortical bone can be considered as a four-phase composite material consisting of osteons, Haversian canals, cement lines and interstitial matrix. These microstructural constituents can directly affect local distributions of stresses and strains, and, hence, crack initiation and propagation. Therefore, understanding the effect of micromorphology of cortical bone on crack initiation and propagation, especially under dynamic loading regimes is of great importance for fracture risk evaluation. In this study, random microstructures of a cortical bone tissue were modelled with finite elements for four groups: healthy (control), young age, osteoporosis and bisphosphonate-treated, based on osteonal morphometric parameters measured from microscopic images for these groups. The developed models were loaded under the same dynamic loading conditions, representing a direct impact incident, resulting in progressive crack propagation. An extended finite-element method (X-FEM) was implemented to realize solution-dependent crack propagation within the microstructured cortical bone tissues. The obtained simulation results demonstrate significant differences due to micromorphology of cortical bone, in terms of crack propagation characteristics for different groups, with the young group showing highest fracture resistance and the senior group the lowest.

Facebook Groups as a Powerful and Dynamic Tool in Medical Education: Mixed-Method Study.

PubMed

Nicolai, Leo; Schmidbauer, Moritz; Gradel, Maximilian; Ferch, Sabine; Antón, Sofía; Hoppe, Boj; Pander, Tanja; von der Borch, Philip; Pinilla, Severin; Fischer, Martin; Dimitriadis, Konstantinos

2017-12-22

Social networking sites, in particular Facebook, are not only predominant in students' social life but are to varying degrees interwoven with the medical curriculum. Particularly, Facebook groups have been identified for their potential in higher education. However, there is a paucity of data on user types, content, and dynamics of study-related Facebook groups. The aim of this study was to identify the role of study-related Facebook group use, characterize medical students that use or avoid using Facebook groups (demographics, participation pattern, and motivation), and analyze student posting behavior, covered topics, dynamics, and limitations in Facebook groups with regards to educational usage. Using a multi-method approach (interviews, focus groups, and qualitative and quantitative analysis of Facebook posts), we analyzed two representative Facebook groups of medical preclinical semesters at Ludwig-Maximilians-University (LMU) Munich. Facebook primary posts and replies over one semester were extracted and evaluated by using thematic content analysis. We developed and applied a coding scheme for studying the frequency and distribution of these posts. Additionally, we interviewed students with various degrees of involvement in the groups, as well as "new minorities," students not registered on Facebook. Facebook groups seem to have evolved as the main tool for medical students at LMU to complement the curriculum and to discuss study-related content. These Facebook groups are self-organizing and quickly adapt to organizational or subject-related challenges posed by the curriculum. A wide range of topics is covered, with a dominance of organization-related posts (58.35% [6916/11,853] of overall posts). By measuring reply rates and comments per category, we were able to identify learning tips and strategies, material sharing, and course content discussions as the most relevant categories. Rates of adequate replies in these categories ranged between 78% (11/14) and 100% (13/13), and the number of comments per post ranged from 8.4 to 13.7 compared with the average overall reply rate of 68.69% (1167/1699) and 3.9 comments per post. User typology revealed social media drivers (>30 posts per semester) as engines of group function, frequent users (11-30 posts), and a majority of average users acting rather as consumers or lurkers (1-10 posts). For the moment, the medical faculty has no active involvement in these groups and therefore no influence on accuracy of information, professionalism, and ethical issues. Nevertheless, faculty could in the future benefit by extracting relevant information, identifying common problems, and understanding semester-related dynamics. ©Leo Nicolai, Moritz Schmidbauer, Maximilian Gradel, Sabine Ferch, Sofía Antón, Boj Hoppe, Tanja Pander, Philip von der Borch, Severin Pinilla, Martin Fischer, Konstantinos Dimitriadis. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 22.12.2017.

Electrocortical Dynamics in Children with a Language-Learning Impairment Before and After Audiovisual Training.

PubMed

Heim, Sabine; Choudhury, Naseem; Benasich, April A

2016-05-01

Detecting and discriminating subtle and rapid sound changes in the speech environment is a fundamental prerequisite of language processing, and deficits in this ability have frequently been observed in individuals with language-learning impairments (LLI). One approach to studying associations between dysfunctional auditory dynamics and LLI, is to implement a training protocol tapping into this potential while quantifying pre- and post-intervention status. Event-related potentials (ERPs) are highly sensitive to the brain correlates of these dynamic changes and are therefore ideally suited for examining hypotheses regarding dysfunctional auditory processes. In this study, ERP measurements to rapid tone sequences (standard and deviant tone pairs) along with behavioral language testing were performed in 6- to 9-year-old LLI children (n = 21) before and after audiovisual training. A non-treatment group of children with typical language development (n = 12) was also assessed twice at a comparable time interval. The results indicated that the LLI group exhibited considerable gains on standardized measures of language. In terms of ERPs, we found evidence of changes in the LLI group specifically at the level of the P2 component, later than 250 ms after the onset of the second stimulus in the deviant tone pair. These changes suggested enhanced discrimination of deviant from standard tone sequences in widespread cortices, in LLI children after training.

Response, analysis, and design of pile groups subjected to static & dynamic lateral loads.

DOT National Transportation Integrated Search

2003-06-01

Static and dynamic lateral load tests were performed on four full-scale pile groups driven at four different spacings. P-multipliers to account for group : interaction effects were back-calculated for each test. P-multipliers were found to be a funct...

Area 2: Inexpensive Monitoring and Uncertainty Assessment of CO2 Plume Migration using Injection Data

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

Srinivasan, Sanjay

2014-09-30

In-depth understanding of the long-term fate of CO₂ in the subsurface requires study and analysis of the reservoir formation, the overlaying caprock formation, and adjacent faults. Because there is significant uncertainty in predicting the location and extent of geologic heterogeneity that can impact the future migration of CO₂ in the subsurface, there is a need to develop algorithms that can reliably quantify this uncertainty in plume migration. This project is focused on the development of a model selection algorithm that refines an initial suite of subsurface models representing the prior uncertainty to create a posterior set of subsurface models thatmore » reflect injection performance consistent with that observed. Such posterior models can be used to represent uncertainty in the future migration of the CO₂ plume. Because only injection data is required, the method provides a very inexpensive method to map the migration of the plume and the associated uncertainty in migration paths. The model selection method developed as part of this project mainly consists of assessing the connectivity/dynamic characteristics of a large prior ensemble of models, grouping the models on the basis of their expected dynamic response, selecting the subgroup of models that most closely yield dynamic response closest to the observed dynamic data, and finally quantifying the uncertainty in plume migration using the selected subset of models. The main accomplishment of the project is the development of a software module within the SGEMS earth modeling software package that implements the model selection methodology. This software module was subsequently applied to analyze CO₂ plume migration in two field projects – the In Salah CO₂ Injection project in Algeria and CO₂ injection into the Utsira formation in Norway. These applications of the software revealed that the proxies developed in this project for quickly assessing the dynamic characteristics of the reservoir were highly efficient and yielded accurate grouping of reservoir models. The plume migration paths probabilistically assessed by the method were confirmed by field observations and auxiliary data. The report also documents the application of the software to answer practical questions such as the optimum location of monitoring wells to reliably assess the migration of CO₂ plume, the effect of CO₂-rock interactions on plume migration and the ability to detect the plume under those conditions and the effect of a slow, unresolved leak on the predictions of plume migration.« less

[The effect of nitrates on the outcome of acute experimental ischemic stroke].

PubMed

Kuzenkov, V S; Krushinskiĭ, A L; Reutov, V P

2012-01-01

Effects of nitrates NaNO(3), KNO(3), Mg(NO(3)) 2 on animals (Wistar rats) were studied on the basis of the experimental model of ischemic stroke induced by the occlusion of two carotid arteries. The animals were divided into two groups: the main group (n=60) and the control group (n=30). Three series of experiments were conducted. In each experiment, the rats of the main group were treated with one of nitrates and the control group was treated with physiological solution. It has been shown that nitrates exert either positive or negative effect depending on the cation type, nitrate concentration and the duration of their action on the dynamics of neurologic disturbances. Conditions of the development of neuroprotective effect of nitrates are discussed.

Immediate effects of dynamic sitting exercise on the lower back mobility of sedentary young adults

PubMed Central

Chatchawan, Uraiwan; Jupamatangb, Unthika; Chanchitc, Sunisa; Puntumetakul, Rungthip; Donpunha, Wanida; Yamauchi, Junichiro

2015-01-01

[Purpose] The aim of this study was to investigate the effects of dynamic sitting exercises during prolonged sitting on the lower back mobility of sedentary young adults. [Subjects and Methods] Seventy-one subjects aged between 18–25 years participated in this study. Following a randomized crossover study design, subjects were randomly assigned to two groups: sitting only and dynamic sitting exercise. The dynamic sitting exercise was a combination of lower back hyperextension and abdominal drawing-in movements which were repeated 6 times in a 1-minute period and performed every 20 minutes during a 2-hour sitting session. Lumbar range of movement was measured with the modified-modified Schober test, and the pain intensity was evaluated using the visual analog scale. [Results] After the experiment, the lumbar range of movement was significantly impaired in the sitting only group; however, it was significantly improved in the dynamic sitting exercise group. There were significant differences in lumbar range of movement of both flexion and extension between the groups. No significant difference in pain intensity between the groups was found. [Conclusion] These results suggest that dynamic sitting exercises during prolonged sitting can prevent decreases in lumbar range of movement in both back flexion and extension following a 2-hour sitting period. PMID:26696698

High-temperature molecular dynamics simulation of aragonite.

PubMed

Miyake, Akira; Kawano, Jun

2010-06-09

For molecular dynamics simulations using aragonite structure as the initial state, a new phase of space group P6₃22 (hexagonal aragonite) appeared at temperatures above 510 K at a pressure of 1 atm. It was a first-order phase transition which occurs metastably within the stable region of calcite and the dT/dP slope of the phase boundary between orthorhombic and hexagonal aragonite was about 1.25 × 10³ K GPa⁻¹. In the hexagonal aragonite structure, CO₃ groups were rotated by 30° around the c axis and move up and down along the c axis from their position in aragonite, and Ca ions were six-coordinated as they are in calcite. The CaO₆ octahedron of hexagonal aragonite was strongly distorted, whereas in the calcite structure it is an almost ideal octahedron. The transition between hexagonal and orthorhombic aragonite involves only small movements of CO₃ groups. Therefore, it is possible that hexagonal aragonite plays an important part in the metastable formation of aragonite within the stability field of calcite and in the development of sector trilling in aragonite.

Dynamic Key Management Schemes for Secure Group Access Control Using Hierarchical Clustering in Mobile Ad Hoc Networks

NASA Astrophysics Data System (ADS)

Tsaur, Woei-Jiunn; Pai, Haw-Tyng

2008-11-01

The applications of group computing and communication motivate the requirement to provide group access control in mobile ad hoc networks (MANETs). The operation in MANETs' groups performs a decentralized manner and accommodated membership dynamically. Moreover, due to lack of centralized control, MANETs' groups are inherently insecure and vulnerable to attacks from both within and outside the groups. Such features make access control more challenging in MANETs. Recently, several researchers have proposed group access control mechanisms in MANETs based on a variety of threshold signatures. However, these mechanisms cannot actually satisfy MANETs' dynamic environments. This is because the threshold-based mechanisms cannot be achieved when the number of members is not up to the threshold value. Hence, by combining the efficient elliptic curve cryptosystem, self-certified public key cryptosystem and secure filter technique, we construct dynamic key management schemes based on hierarchical clustering for securing group access control in MANETs. Specifically, the proposed schemes can constantly accomplish secure group access control only by renewing the secure filters of few cluster heads, when a cluster head joins or leaves a cross-cluster. In such a new way, we can find that the proposed group access control scheme can be very effective for securing practical applications in MANETs.

Assessing participants' perceptions on group-based principles for action in community-based health enhancing physical activity programmes: The APEF tool.

PubMed

Herens, Marion; Wagemakers, Annemarie

2017-12-01

In community-based health enhancing physical activity (CBHEPA) programmes, group-based principles for action such as active participation, enjoyment, and fostering group processes are widely advocated. However, not much is known about participants' perceptions of these principles as there are no assessment tools available. Therefore, this article describes the development of the APEF (Active Participation, Enjoyment, and Fostering group processes) tool and reports on its implementation in a Dutch CBHEPA programme. Indicators for the principles have been identified from literature research, interviews with professionals, and secondary analysis of three group interviews with 11 practitioners. To address the identified indicators, the APEF tool was developed, pretested, and used in 10 focus groups with 76 participants. The APEF tool consists of eight statements about group-based principles for action, on which CBHEPA participants vote, followed by in-depth discussion. The voting procedure engages participants. Spider diagrams visualise participants' perceptions of group-based principles. The APEF tool addresses the challenge of relating group level outcomes to individual outcomes such as physical activity behaviour. The tool facilitates as well as evaluates group-based principles for action, it stimulates dialogue and is culturally sensitive, but it needs strong facilitating skills to manage group dynamics. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

[Serum calcium and phosphorus concentration and alkaline phosphatase activity in healthy children during growth and development].

PubMed

Savić, Ljiljana; Savić, Dejan

2008-01-01

Many changes happen during growth and development in an organism as a result of important hormon changes, especially biohumoral ones. These changes make a problem when interpreting biochemical results in pediatric population. The most important changes are intensive calcium and phosphorus metabolic turnover in bone tissue with changes in alkaline phosphatase activity as a result of osteoblast activity. The aim of this study was to follow the serum calcium and phosphorus concentration and alkaline phosphatase activity in children 1-15 years old in different growth and development period and of different sexes and to fortify the influence of growth and development dynamics on biohumoral status in healthy male and female children. We evaluated 117 healthy children of both sexes from 1-15 years of age and divided them into three age groups: 1-5, 6-10 and 11-15 years. We followed the serum calcium and phosphorus concentration and alkaline phosphatase activity in different groups and in different sexes. Our investigation found significantly higher values of serum calcium in boys than in girls with no important changes between the age groups and significantly higher values of serum phosphorus in the youngest age group in all children and in different sexes with no important sex differences. Alkaline phosphatase activity followed the growth spurt and was the biggest in 6-10 years group in girls and in 11-15 years group in boys.

Overview of MSFC's Applied Fluid Dynamics Analysis Group Activities

NASA Technical Reports Server (NTRS)

Garcia, Roberto; Griffin, Lisa; Williams, Robert

2003-01-01

TD64, the Applied Fluid Dynamics Analysis Group, is one of several groups with high-fidelity fluids design and analysis expertise in the Space Transportation Directorate at Marshall Space Flight Center (MSFC). TD64 assists personnel working on other programs. The group participates in projects in the following areas: turbomachinery activities, nozzle activities, combustion devices, and the Columbia accident investigation.

Computer-Aided Group Problem Solving for Unified Life Cycle Engineering (ULCE)

DTIC Science & Technology

1989-02-01

defining the problem, generating alternative solutions, evaluating alternatives, selecting alternatives, and implementing the solution. Systems...specialist in group dynamics, assists the group in formulating the problem and selecting a model framework. The analyst provides the group with computer...allocating resources, evaluating and selecting options, making judgments explicit, and analyzing dynamic systems. c. University of Rhode Island Drs. Geoffery

SeCom - Serious Community 2.0 prevent flooding

NASA Astrophysics Data System (ADS)

Komma, Juergen; Breuer, Roman; Sewilam, Hani; Concia, Francesca; Aliprandi, Bruno; Siegmund, Sabine; Goossens, Jannis

2013-04-01

There is a significant need for raising the awareness and building the capacity of water professionals in different water sectors cross Europe. There is also a need for qualified graduates to implement the EU Flood Risk Directive (FRD). The main aim of this work is to prepare and build the capacity of both groups in flood risk management through identifying synergies, sharing knowledge, and strengthen partnerships between universities and different stakeholders(mainly water professionals). The specific objectives are to develop; a) Development of a dynamic and active tool that allows all target-groups/users to assess their knowledge about flood risk management. b) Development of an innovative, active and problem-based learning methodology for flood risk education and training. c)Development of flood related Vocational Education & Training (VET) modules for water professionals (involving the students to gain practical experience). This will include some modules for undergraduate students on flood risk management and protection.

Focus Upon Implementing the GGOS Decadal Vision for Geohazards Monitoring

NASA Astrophysics Data System (ADS)

LaBrecque, John; Stangl, Gunter

2017-04-01

The Global Geodetic Observing System of the IAG identified present and future roles for Geodesy in the development and well being of the global society. The GGOS is focused upon the development of infrastructure, information, analysis, and educational systems to advance the International Global Reference Frame, the International Celestial Reference System, the International Height Reference System, atmospheric dynamics, sea level change and geohazards monitoring. The geohazards initiative is guided by an eleven nation working group initially focused upon the development and integration of regional multi-GNSS networks and analysis systems for earthquake and tsunami early warning. The opportunities and challenges being addressed by the Geohazards working group include regional network design, algorithm development and implementation, communications, funding, and international agreements on data access. This presentation will discuss in further detail these opportunities and challenges for the GGOS focus upon earthquake and tsunami early warning.

Dynamic Structure-Based Pharmacophore Model Development: A New and Effective Addition in the Histone Deacetylase 8 (HDAC8) Inhibitor Discovery

PubMed Central

Thangapandian, Sundarapandian; John, Shalini; Lee, Yuno; Kim, Songmi; Lee, Keun Woo

2011-01-01

Histone deacetylase 8 (HDAC8) is an enzyme involved in deacetylating the amino groups of terminal lysine residues, thereby repressing the transcription of various genes including tumor suppressor gene. The over expression of HDAC8 was observed in many cancers and thus inhibition of this enzyme has emerged as an efficient cancer therapeutic strategy. In an effort to facilitate the future discovery of HDAC8 inhibitors, we developed two pharmacophore models containing six and five pharmacophoric features, respectively, using the representative structures from two molecular dynamic (MD) simulations performed in Gromacs 4.0.5 package. Various analyses of trajectories obtained from MD simulations have displayed the changes upon inhibitor binding. Thus utilization of the dynamically-responded protein structures in pharmacophore development has the added advantage of considering the conformational flexibility of protein. The MD trajectories were clustered based on single-linkage method and representative structures were taken to be used in the pharmacophore model development. Active site complimenting structure-based pharmacophore models were developed using Discovery Studio 2.5 program and validated using a dataset of known HDAC8 inhibitors. Virtual screening of chemical database coupled with drug-like filter has identified drug-like hit compounds that match the pharmacophore models. Molecular docking of these hits reduced the false positives and identified two potential compounds to be used in future HDAC8 inhibitor design. PMID:22272142

Influences of posterior-located center of gravity on lumbar extension strength, balance, and lumbar lordosis in chronic low back pain.

PubMed

Kim, Dae-Hun; Park, Jin-Kyu; Jeong, Myeong-Kyun

2014-01-01

In patients with chronic low back pain, the center of gravity (COG) is abnormally located posterior to the center in most cases. The purpose of this study was to examine the effects of posterior-located COG on the functions (lumbar extension strength, and static and dynamic balance) and structure (lumbar lordosis angle and lumbosacral angle) of the lumbar spine. In this study, the COG of chronic low back pain patients who complained of only low back pain were examined using dynamic body balance equipment. A total of 164 subjects participated in the study (74 males and 90 females), and they were divided into two groups of 82 patients each. One group (n=82) consisted of patients whose COG was located at the center (C-COG); the other group (n=82) consisted of patients whose COG was located posterior to the center (P-COG). The following measures assessed the lumber functions and structures of the two groups: lumbar extension strength, moving speed of static and dynamic COGs, movement distance of the static and dynamic COGs, lumbar lordosis angle, and lumbosacral angle. The measured values were analyzed using independent t-tests. The group of patients with P-COG showed more decreases in lumbar extension strength, lumbar lordosis angle, and lumbosacral angle compared to the group of patients with C-COG. Also this group showed increases in moving speed and movement distance of the static COG. However, there were no differences in moving speed and movement distance of the dynamic COG between the two groups. These findings suggest that chronic LBP patients with P-COG have some disadvantages to establish lumbar extension strength and static and dynamic balance, which require specific efforts to maintain a neutral position and to control posture.

Constraint Embedding Technique for Multibody System Dynamics

NASA Technical Reports Server (NTRS)

Woo, Simon S.; Cheng, Michael K.

2011-01-01

Multibody dynamics play a critical role in simulation testbeds for space missions. There has been a considerable interest in the development of efficient computational algorithms for solving the dynamics of multibody systems. Mass matrix factorization and inversion techniques and the O(N) class of forward dynamics algorithms developed using a spatial operator algebra stand out as important breakthrough on this front. Techniques such as these provide the efficient algorithms and methods for the application and implementation of such multibody dynamics models. However, these methods are limited only to tree-topology multibody systems. Closed-chain topology systems require different techniques that are not as efficient or as broad as those for tree-topology systems. The closed-chain forward dynamics approach consists of treating the closed-chain topology as a tree-topology system subject to additional closure constraints. The resulting forward dynamics solution consists of: (a) ignoring the closure constraints and using the O(N) algorithm to solve for the free unconstrained accelerations for the system; (b) using the tree-topology solution to compute a correction force to enforce the closure constraints; and (c) correcting the unconstrained accelerations with correction accelerations resulting from the correction forces. This constraint-embedding technique shows how to use direct embedding to eliminate local closure-loops in the system and effectively convert the system back to a tree-topology system. At this point, standard tree-topology techniques can be brought to bear on the problem. The approach uses a spatial operator algebra approach to formulating the equations of motion. The operators are block-partitioned around the local body subgroups to convert them into aggregate bodies. Mass matrix operator factorization and inversion techniques are applied to the reformulated tree-topology system. Thus in essence, the new technique allows conversion of a system with closure-constraints into an equivalent tree-topology system, and thus allows one to take advantage of the host of techniques available to the latter class of systems. This technology is highly suitable for the class of multibody systems where the closure-constraints are local, i.e., where they are confined to small groupings of bodies within the system. Important examples of such local closure-constraints are constraints associated with four-bar linkages, geared motors, differential suspensions, etc. One can eliminate these closure-constraints and convert the system into a tree-topology system by embedding the constraints directly into the system dynamics and effectively replacing the body groupings with virtual aggregate bodies. Once eliminated, one can apply the well-known results and algorithms for tree-topology systems to solve the dynamics of such closed-chain system.

Leadership Styles

ERIC Educational Resources Information Center

Val, Carlin; Kemp, Jess

2012-01-01

This study examines how a group's dynamic changes under the influence of different leadership styles, and determines what leadership style works best in a large group expedition. The main question identified was "What roles can a leader play in affecting the dynamic of a large group while partaking in a field expedition?" The following…

Group Dynamics in the Interior Design Studio: Student Perceptions

ERIC Educational Resources Information Center

Hill, Caroline

2008-01-01

This article presents the findings of a study measuring the classroom climates in collegiate interior design studios and considers these findings within the group dynamics theory framework. Three groups of students completed the College Classroom Environment Scales (CCES) questionnaire. Five of the six CCES subscale F ratios were statistically…

Evolution and Social Dynamics of Acknowledged Research Groups

ERIC Educational Resources Information Center

López-Yáñez, Julián; Altopiedi, Mariana

2015-01-01

Changes in higher education institutions characteristic of a knowledge society are strongly affecting academic life, scientists' working conditions and the social dynamics of scientific groups. In such situations, it is important to understand the different ways in which these groups are tackling the structural dilemmas posed by the changes…

Phytoplankton dynamics of a subtropical reservoir controlled by the complex interplay among hydrological, abiotic, and biotic variables.

PubMed

Kuo, Yi-Ming; Wu, Jiunn-Tzong

2016-12-01

This study was conducted to identify the key factors related to the spatiotemporal variations in phytoplankton abundance in a subtropical reservoir from 2006 to 2010 and to assist in developing strategies for water quality management. Dynamic factor analysis (DFA), a dimension-reduction technique, was used to identify interactions between explanatory variables (i.e., environmental variables) and abundance (biovolume) of predominant phytoplankton classes. The optimal DFA model significantly described the dynamic changes in abundances of predominant phytoplankton groups (including dinoflagellates, diatoms, and green algae) at five monitoring sites. Water temperature, electrical conductivity, water level, nutrients (total phosphorus, NO 3 -N, and NH 3 -N), macro-zooplankton, and zooplankton were the key factors affecting the dynamics of aforementioned phytoplankton. Therefore, transformations of nutrients and reactions between water quality variables and aforementioned processes altered by hydrological conditions may also control the abundance dynamics of phytoplankton, which may represent common trends in the DFA model. The meandering shape of Shihmen Reservoir and its surrounding rivers caused a complex interplay between hydrological conditions and abiotic and biotic variables, resulting in phytoplankton abundance that could not be estimated using certain variables. Additional water quality and hydrological variables at surrounding rivers and monitoring plans should be executed a few days before and after reservoir operations and heavy storm, which would assist in developing site-specific preventive strategies to control phytoplankton abundance.

Orientational Dynamics of a Functionalized Alkyl Planar Monolayer Probed by Polarization-Selective Angle-Resolved Infrared Pump-Probe Spectroscopy.

PubMed

Nishida, Jun; Yan, Chang; Fayer, Michael D

2016-10-12

Polarization-selective angle-resolved infrared pump-probe spectroscopy was developed and used to study the orientational dynamics of a planar alkylsiloxane monolayer functionalized with a rhenium metal carbonyl headgroup on an SiO 2 surface. The technique, together with a time-averaged infrared linear dichroism measurement, characterized picosecond orientational relaxation of the headgroup occurring at the monolayer-air interface by employing several sets of incident angles of the infrared pulses relative to the sample surface. By application of this method and using a recently developed theory, it was possible to extract both the out-of-plane and "mainly"-in-plane orientational correlation functions in a model-independent manner. The observed correlation functions were compared with theoretically derived correlation functions based on several dynamical models. The out-of-plane correlation function reveals the highly restricted out-of-plane motions of the head groups and also suggests that the angular distribution of the transition dipole moments is bimodal. The mainly-in-plane correlation function, for the sample studied here with the strongly restricted out-of-plane motions, essentially arises from the purely in-plane dynamics. In contrast to the out-of-plane dynamics, significant in-plane motions occurring over various time scales were observed including an inertial motion, a restricted wobbling motion of ∼3 ps, and complete randomization occurring in ∼25 ps.

Nonlinear dynamics in the perceptual grouping of connected surfaces.

PubMed

Hock, Howard S; Schöner, Gregor

2016-09-01

Evidence obtained using the dynamic grouping method has shown that the grouping of an object's connected surfaces has properties characteristic of a nonlinear dynamical system. When a surface's luminance changes, one of its boundaries is perceived moving across the surface. The direction of this dynamic grouping (DG) motion indicates which of two flanking surfaces has been grouped with the changing surface. A quantitative measure of overall grouping strength (affinity) for adjacent surfaces is provided by the frequency of DG motion perception in directions promoted by the grouping variables. It was found that: (1) variables affecting surface grouping for three-surface objects evolve over time, settling at stable levels within a single fixation, (2) how often DG motion is perceived when a surface's luminance is perturbed (changed) depends on the pre-perturbation affinity state of the surface grouping, (3) grouping variables promoting the same surface grouping combine cooperatively and nonlinearly (super-additively) in determining the surface grouping's affinity, (4) different DG motion directions during different trials indicate that surface grouping can be bistable, which implies that inhibitory interactions have stabilized one of two alternative surface groupings, and (5) when alternative surface groupings have identical affinity, stochastic fluctuations can break the symmetry and inhibitory interactions can then stabilize one of the surface groupings, providing affinity levels are not too high (which results in bidirectional DG motion). A surface-grouping network is proposed within which boundaries vary in salience. Low salience or suppressed boundaries instantiate surface grouping, and DG motion results from changes in boundary salience. Copyright © 2015 Elsevier Ltd. All rights reserved.

Coastal Community Group for Coastal Resilient in Timbulsloko Village, Sayung, Demak Regency, Indonesia

NASA Astrophysics Data System (ADS)

Purnaweni, Hartuti; Kismartini; Hadi, Sudharto P.; Soraya, Ike

2018-02-01

Coastal areas are very dynamic and fragile environment, demanding for policies to preserve these areas as materialized in the Resilient Coastal Development Program (PKPT) by the Indonesian government. Amongst the targeted area was Timbulsloko Village in Sayung District, Demak Regency, which coastal areas is severely damaged by erosion. This article analyzed the development of the Coastal Community Group (CCG) related to the PKPT program in Timbulsloko village, especially in how the group is empowered to increase the community's resilient in facing the disaster. This study, applied an analytical descriptive method, used the development of the CCG as phenomenon. Primary data was collected through observation and in-depth interviews with stakeholders, accompanying the secondary data. The result shows that the PKPT funding was mostly spent on infrastructure development and used for project management, not for optimizing local economic empowerment. After the completion of the PKPT, there are no actions or following programs to keep the physical results constructed by the CCG. Accordingly, the orientation towards the CCG building capacity for Timbulsloko community's ecological resilience had not been optimally implemented. This study recommended a "putting the last first" policy approach to preparing the local community. The government must play a stronger role in encouraging a self-help local group for strong human development

The dynamics of shared leadership: building trust and enhancing performance.

PubMed

Drescher, Marcus A; Korsgaard, M Audrey; Welpe, Isabell M; Picot, Arnold; Wigand, Rolf T

2014-09-01

In this study, we examined how the dynamics of shared leadership are related to group performance. We propose that, over time, the expansion of shared leadership within groups is related to growth in group trust. In turn, growth in group trust is related to performance improvement. Longitudinal data from 142 groups engaged in a strategic simulation game over a 4-month period provide support for positive changes in trust mediating the relationship between positive changes in shared leadership and positive changes in performance. Our findings contribute to the literature on shared leadership and group dynamics by demonstrating how the growth in shared leadership contributes to the emergence of trust and a positive performance trend over time. PsycINFO Database Record (c) 2014 APA, all rights reserved.

The Dynamics of School Change: Response to the Article "Comer's School Development Program in Prince George's Count, Maryland: A Theory-based Evaluation," by Thomas D. Cook et al.

ERIC Educational Resources Information Center

Comer, James P.; Haynes, Norris M.

1999-01-01

Comments on a study of Comer's School Development Model, indicating that the study, as conducted, was not a study of the model but a limited study of the effects of one application of the model's process. In addition, the evaluation was carried out over only 2 years for each group, when experience shows that at least 3 years are necessary to show…

Conceptualizing Stakeholders' Perceptions of Ecosystem Services: A Participatory Systems Mapping Approach

NASA Astrophysics Data System (ADS)

Lopes, Rita; Videira, Nuno

2015-12-01

A participatory system dynamics modelling approach is advanced to support conceptualization of feedback processes underlying ecosystem services and to foster a shared understanding of leverage intervention points. The process includes systems mapping workshop and follow-up tasks aiming at the collaborative construction of causal loop diagrams. A case study developed in a natural area in Portugal illustrates how a stakeholder group was actively engaged in the development of a conceptual model depicting policies for sustaining the climate regulation ecosystem service.

Effect of a new device for sustained progesterone release on the progesterone concentration, ovarian follicular diameter, time of ovulation and pregnancy rate of ewes.

PubMed

Dias, Lilian Mara Kirsch; de Barros, Marina Berrettini Paes; Viau, Priscila; Sales, José Nélio de Sousa; Valentim, Renato; dos Santos, Fernanda Ferreira; da Cunha, Manoel Claudio; Marino, Carolina Tobias; de Oliveira, Claudio Alvarenga

2015-04-01

This study evaluated the effectiveness of a new progesterone intravaginal device (DPR) in ewes through four experiments: Experiment 1 compared the circulating progesterone concentration of ovariectomized ewes that received either a new or a re-used DPR. Experiment 2 compared the progesterone concentration between DPR-estrous-synchronized ewes and naturally estrous-cycling ewes. Experiment 3 evaluated the effect of new and re-used DPRs on ovarian follicular dynamics and time of ovulation of estrous cycling ewes. Experiment 4 compared the pregnancy rate after the use of a DPR and Controlled Internal Drug Releasing Device (CIDR). The mean concentration of progesterone released by the DPR device during its first use (New Group: 5.1 ± 0.5 ng/ml) was greater than that during the second use (Re-used Group: 2.4 ± 0.3 ng/ml). There was no difference between the animals that received DPR devices for first and second use in terms of ovulatory follicle diameter, follicular wave emergence day for ovulatory follicle and period of ovulatory wave of ovarian follicular development. However, there was a significant difference between groups regarding the time between DPR device removal and first ovulation (New Group: 71.7 ± 2.5h and Re-Used Group: 63.9 ± 2.7h). Pregnancy rates were similar between ewes with DPR and CIDR devices. It was concluded that DPR is effective in increasing and maintaining progesterone concentrations, controlling follicular dynamics, promoting synchronized times of ovulation from healthy follicles, promoting development of a competent corpus luteum and when used results in pregnancy rates similar to that with use of the CIDR. Copyright © 2015 Elsevier B.V. All rights reserved.

Dynamics of vaccination strategies via projected dynamical systems.

PubMed

Cojocaru, Monica-Gabriela; Bauch, Chris T; Johnston, Matthew D

2007-07-01

Previous game theoretical analyses of vaccinating behaviour have underscored the strategic interaction between individuals attempting to maximise their health states, in situations where an individual's health state depends upon the vaccination decisions of others due to the presence of herd immunity. Here, we extend such analyses by applying the theories of variational inequalities (VI) and projected dynamical systems (PDS) to vaccination games. A PDS provides a dynamics that gives the conditions for existence, uniqueness and stability properties of Nash equilibria. In this paper, it is used to analyse the dynamics of vaccinating behaviour in a population consisting of distinct social groups, where each group has different perceptions of vaccine and disease risks. In particular, we study populations with two groups, where the size of one group is strictly larger than the size of the other group (a majority/minority population). We find that a population with a vaccine-inclined majority group and a vaccine-averse minority group exhibits higher average vaccine coverage than the corresponding homogeneous population, when the vaccine is perceived as being risky relative to the disease. Our model also reproduces a feature of real populations: In certain parameter regimes, it is possible to have a majority group adopting high vaccination rates and simultaneously a vaccine-averse minority group adopting low vaccination rates. Moreover, we find that minority groups will tend to exhibit more extreme changes in vaccinating behaviour for a given change in risk perception, in comparison to majority groups. These results emphasise the important role played by social heterogeneity in vaccination behaviour, while also highlighting the valuable role that can be played by PDS and VI in mathematical epidemiology.

Spatial-size scaling of pedestrian groups under growing density conditions

NASA Astrophysics Data System (ADS)

Zanlungo, Francesco; Brščić, Dražen; Kanda, Takayuki

2015-06-01

We study the dependence on crowd density of the spatial size, configuration, and velocity of pedestrian social groups. We find that, in the investigated density range, the extension of pedestrian groups in the direction orthogonal to that of motion decreases linearly with the pedestrian density around them, both for two- and three-person groups. Furthermore, we observe that at all densities, three-person groups walk slower than two-person groups, and the latter are slower than individual pedestrians, the differences in velocities being weakly affected by density. Finally, we observe that three-person groups walk in a V-shaped formation regardless of density, with a distance between the pedestrians in the front and back again almost independent of density, although the configuration appears to be less stable at higher densities. These findings may facilitate the development of more realistic crowd dynamics models and simulators.

The Structure of Social Exchange in Self-Help Support Groups: Development of a Measure

PubMed Central

Brown, Louis D.; Tang, Xiaohui; Hollman, Ruth L.

2014-01-01

Self-help support groups are indigenous community resources designed to help people manage a variety of personal challenges, from alcohol abuse to xeroderma pigmentosum. The social exchanges that occur during group meetings are central to understanding how people benefit from participation. This paper examines the different types of social exchange behaviors that occur during meetings, using two studies to develop empirically distinct scales that reliably measure theoretically important types of exchange. Resource theory informed the initial measurement development efforts. Exploratory factor analyses from the first study led to revisions in the factor structure of the social exchange scales. The revised measure captured the exchange of emotional support, experiential information, humor, unwanted behaviors, and exchanges outside meetings. Confirmatory factor analyses from a follow-up study with a different sample of self-help support groups provided good model fit, suggesting the revised structure accurately represented the data. Further, the scales demonstrated good convergent and discriminant validity with related constructs. Future research can use the scales to identify aspects of social exchange that are most important in improving health outcomes among self-help support group participants. Groups can use the scales in practice to celebrate strengths and address weaknesses in their social exchange dynamics. PMID:24398622

The use of SWOT analysis to explore and prioritize conservation and development strategies for local cattle breeds.

PubMed

Martín-Collado, D; Díaz, C; Mäki-Tanila, A; Colinet, F; Duclos, D; Hiemstra, S J; Gandini, G

2013-06-01

SWOT (Strengths, Weaknesses, Opportunities and Threats) analysis is a tool widely used to help in decision making in complex systems. It suits to exploring the issues and measures related to the conservation and development of local breeds, as it allows the integration of many driving factors influencing breed dynamics. We developed a quantified SWOT method as a decision-making tool for identification and ranking of conservation and development strategies of local breeds, and applied it to a set of 13 cattle breeds of six European countries. The method has four steps: definition of the system, identification and grouping of the driving factors, quantification of the importance of driving factors and identification and prioritization of the strategies. The factors were determined following a multi-stakeholder approach and grouped with a three-level structure. Animal genetic resources expert groups ranked the factors, and a quantification process was implemented to identify and prioritize strategies. The proposed SWOT methodology allows analyzing the dynamics of local cattle breeds in a structured and systematic way. It is a flexible tool developed to assist different stakeholders in defining the strategies and actions. The quantification process allows the comparison of the driving factors and the prioritization of the strategies for the conservation and development of local cattle breeds. We identified 99 factors across the breeds. Although the situation is very heterogeneous, the future of these breeds may be promising. The most important strengths and weaknesses were related to production systems and farmers. The most important opportunities were found in marketing new products, whereas the most relevant threats were found in selling the current products. The across-breed strategies utility decreased as they gained specificity. Therefore, the strategies at European level should focus on general aspects and be flexible enough to be adapted to the country and breed specificities.

OSIRIS-REx and mission sample science: The return of at least 60 g of pristine regolith from asteroid Bennu

NASA Astrophysics Data System (ADS)

Connolly, H. C., Jr.; Lauretta, D. S.

2014-07-01

Introduction: The Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) asteroid sample return mission was selected by NASA in May 2011 as the third New Frontiers mission. The target, (101955) Bennu, is a B-type near-Earth asteroid (NEA), hypothesized to be similar to CI or CM carbonaceous chondrites. The key science objectives of the mission are summarized in [1]. To meet these science objectives, the science team is coordinated and governed by the Science Executive Council (SEC): A group of six persons that run various elements of mission science. Mission Sample Science (MSS) is charged with analysis of the returned sample. Mission Sample Science: MSS is run by a Mission Scientist and composed of the following working groups: Carbonaceous Meteorite Working Group (CMWG), Dynamical Evolution Working Group (DEWG), Regolith Development Working Group (RDWG), Sample Analysis Working Group (SampleWG), Sample Site Science Working Group (SSSWG), and TAGSAM Working Group (TAGSAMWG). CMWG works to define and create well-characterized test samples, both natural and synthetic, for the development of spectral test data. These data are used to verify the depth and accuracy of spectral analysis techniques for processing data collected by the OSIRIS-REx spectrometers (OVIRS and OTES). The DEWG is charged with constraining the history of asteroid Bennu from main-belt asteroid to NEA. They also work closely with the SampleWG to define the hypotheses for the dynamical evolution of Bennu through the analysis of the returned sample. The RDWG is focused on developing constraints on the origin and evolution of regolith on Bennu through investigations of the surface geology and, working with the SampleWG, test these hypotheses through sample analysis. RDWG is also focused on the analysis of the sampling event and reconstructing what occurred during the event. SampleWG is focused on documenting Contamination Knowledge, which is distinct but related to mission Contamination Control. The main deliverable for this working group is the Sample Analysis Plan, due in 2019. Furthermore, it is this working group that is responsible for constituting the Preliminary Examination Team (PET) and performing the analyses of the returned sample during the first six months after return. SSSWG has the main deliverable of providing to the project the Science Value Maps (SVMs), which are part of the sample site selection process. If we can deliver the spacecraft to candidate sample sites, if it is safe to sample at them, and if there is material that can be ingested, SVMs will be a semi-quantitative aid in picking the optimum site to meet mission science goals. Finally, TAGSAM (Touch And Go Sample Acquisition Mechanism) is the sampler for the mission and this working group is concerned primarily with characterizing TAGSAM capabilities against a range of regolith types. Mission Sample Science provides an over-arching structure to reconstruct the pre- and post-accretion history of Bennu from the formation of pre-solar grains, chondrules, up to geological activity within the asteroid to its final dynamical evolution through analysis of the returned sample using a wide range of disciplines and expertise.

POLYANA-A tool for the calculation of molecular radial distribution functions based on Molecular Dynamics trajectories

NASA Astrophysics Data System (ADS)

Dimitroulis, Christos; Raptis, Theophanes; Raptis, Vasilios

2015-12-01

We present an application for the calculation of radial distribution functions for molecular centres of mass, based on trajectories generated by molecular simulation methods (Molecular Dynamics, Monte Carlo). When designing this application, the emphasis was placed on ease of use as well as ease of further development. In its current version, the program can read trajectories generated by the well-known DL_POLY package, but it can be easily extended to handle other formats. It is also very easy to 'hack' the program so it can compute intermolecular radial distribution functions for groups of interaction sites rather than whole molecules.

[Indicators of general, cerebral, and regional hemodynamics in myopic schoolchildren aged 13-15 years].

PubMed

Iastrebtseva, T A; Chuprov, A D; Plotnikova, Iu A

2002-01-01

110 schoolchildren aged 13-15 years were examined. 24 of them had pseudomyopia and 6 patients myopia of various forms. A control group consisted of 38 children. Central hemodynamics was estimated by average dynamic pressure, cerebral hemodynamics--by rheoencephalography, regional hemodynamics--by dopplerography of the internal carotid and suprapubic arteries. It was found that with myopia progression, the average dynamic pressure positively comes down with reduction of reographic waves amplitude in rheogram. The blood flow rate in internal carotid and suprapubic arteries has no substantial impact on myopia course. Predisposition to arterial hypotension is a risk factor for myopia development and progression.

PD2P: PanDA Dynamic Data Placement for ATLAS

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

Maeno, T.; De, K.; Panitkin, S.

2012-12-13

The PanDA (Production and Distributed Analysis) system plays a key role in the ATLAS distributed computing infrastructure. PanDA is the ATLAS workload management system for processing all Monte-Carlo (MC) simulation and data reprocessing jobs in addition to user and group analysis jobs. The PanDA Dynamic Data Placement (PD2P) system has been developed to cope with difficulties of data placement for ATLAS. We will describe the design of the new system, its performance during the past year of data taking, dramatic improvements it has brought about in the efficient use of storage and processing resources, and plans for the future.

Reversing DNA Methylation: Mechanisms, Genomics, and Biological Functions

PubMed Central

Wu, Hao; Zhang, Yi

2014-01-01

Methylation of cytosines in the mammalian genome represents a key epigenetic modification and is dynamically regulated during development. Compelling evidence now suggests that dynamic regulation of DNA methylation is mainly achieved through a cyclic enzymatic cascade comprised of cytosine methylation, iterative oxidation of methyl group by TET dioxygenases, and restoration of unmodified cytosines by either replication-dependent dilution or DNA glycosylase-initiated base excision repair. In this review, we discuss the mechanism and function of DNA demethylation in mammalian genomes, focusing particularly on how developmental modulation of the cytosine-modifying pathway is coupled to active reversal of DNA methylation in diverse biological processes. PMID:24439369

User's instructions for the Guyton circulatory dynamics model using the Univac 1110 batch and demand processing (with graphic capabilities)

NASA Technical Reports Server (NTRS)

Archer, G. T.

1974-01-01

The model presents a systems analysis of a human circulatory regulation based almost entirely on experimental data and cumulative present knowledge of the many facets of the circulatory system. The model itself consists of eighteen different major systems that enter into circulatory control. These systems are grouped into sixteen distinct subprograms that are melded together to form the total model. The model develops circulatory and fluid regulation in a simultaneous manner. Thus, the effects of hormonal and autonomic control, electrolyte regulation, and excretory dynamics are all important and are all included in the model.

Comparative effectiveness of lumbar stabilization, dynamic strengthening, and Pilates on chronic low back pain: randomized clinical trial.

PubMed

Bhadauria, Esha A; Gurudut, Peeyoosha

2017-08-01

The aim of the present study was to compare three different forms of exercises namely lumbar stabilization, dynamic strengthening, and Pilates on chronic low back pain (LBP) in terms of pain, range of motion, core strength and function. In this study, 44 subjects suffering from non-specific LBP for more than 3 months were randomly allocated into the lumbar stabilization group, the dynamic strengthening group, and the Pilates group. Ten sessions of exercises for 3 weeks were prescribed along with interferential current and hot moist pack. Pain was assessed by visual analog scale, functional affection by modified Oswestry Disability Questionnaire, range of motion by assessing lumbar flexion and extension by modified Schober test and core strength was assessed by pressure biofeedback on day 1 and day 10 of the treatment. There was reduction of pain, improvement in range of motion, functional ability and core strength in all the 3 exercise groups. The improvement was significantly greater in the lumbar stabilization group for all the outcome measures, when compared the posttreatment after 10th session. Pairwise comparison showed that there was greater reduction of disability in the Pilates group than the dynamic strengthening group. It was concluded that the lumbar stabilization is more superior compared to the dynamic strengthening and Pilates in chronic nonspecific LBP. However, long-term benefits need to be assessed and compared with prospective follow-up studies.

Transfer of Dynamic Learning Across Postures

PubMed Central

Wolpert, Daniel M.

2009-01-01

When learning a difficult motor task, we often decompose the task so that the control of individual body segments is practiced in isolation. But on re-composition, the combined movements can result in novel and possibly complex internal forces between the body segments that were not experienced (or did not need to be compensated for) during isolated practice. Here we investigate whether dynamics learned in isolation by one part of the body can be used by other parts of the body to immediately predict and compensate for novel forces between body segments. Subjects reached to targets while holding the handle of a robotic, force-generating manipulandum. One group of subjects was initially exposed to the novel robot dynamics while seated and was then tested in a standing position. A second group was tested in the reverse order: standing then sitting. Both groups adapted their arm dynamics to the novel environment, and this movement learning transferred between seated and standing postures and vice versa. Both groups also generated anticipatory postural adjustments when standing and exposed to the force field for several trials. In the group that had learned the dynamics while seated, the appropriate postural adjustments were observed on the very first reach on standing. These results suggest that the CNS can immediately anticipate the effect of learned movement dynamics on a novel whole-body posture. The results support the existence of separate mappings for posture and movement, which encode similar dynamics but can be adapted independently. PMID:19710374

Effects of Age on Dynamic Accommodation

PubMed Central

Lockhart, Thurmon E.; Shi, Wen

2010-01-01

Visual accommodation plays a critical role in one’s visual perception and activities of daily living. Age-related accommodation loss poses an increased risk to older adults’ safety and independence. Although extensive effort has been made towards understanding the effect of age on steady-state accommodation, dynamic aspects of accommodation is still unknown. A study was therefore conducted to investigate age-related dynamic accommodative characteristics utilizing a modified autorefractor. Ten individuals from each of three age groups (i.e., younger group: 20 to 29 years old, middle-aged group: 40 to 49 years old, and older group: 60 to 69 years old) were recruited and their dynamic accommodation responses were examined. The laboratory experiment was designed to assess dynamic accommodation associated with an abrupt change from a constant far target (400 cm, 50 cd/m2) to a near target (70 cm, 100 cd/m2 or 20 cd/m2), which aimed to simulate car dashboard reading behavior while driving. The results of the study indicated that age and target intensity both had a significant impact on dynamic accommodation. These effects were attributed to both the age-related physiological limitation of the eye as well as to central neural processing delay. A method of measuring dynamic accommodation and the implications of the study are discussed. PMID:20582770

Think locally, act locally: detection of small, medium-sized, and large communities in large networks.

PubMed

Jeub, Lucas G S; Balachandran, Prakash; Porter, Mason A; Mucha, Peter J; Mahoney, Michael W

2015-01-01

It is common in the study of networks to investigate intermediate-sized (or "meso-scale") features to try to gain an understanding of network structure and function. For example, numerous algorithms have been developed to try to identify "communities," which are typically construed as sets of nodes with denser connections internally than with the remainder of a network. In this paper, we adopt a complementary perspective that communities are associated with bottlenecks of locally biased dynamical processes that begin at seed sets of nodes, and we employ several different community-identification procedures (using diffusion-based and geodesic-based dynamics) to investigate community quality as a function of community size. Using several empirical and synthetic networks, we identify several distinct scenarios for "size-resolved community structure" that can arise in real (and realistic) networks: (1) the best small groups of nodes can be better than the best large groups (for a given formulation of the idea of a good community); (2) the best small groups can have a quality that is comparable to the best medium-sized and large groups; and (3) the best small groups of nodes can be worse than the best large groups. As we discuss in detail, which of these three cases holds for a given network can make an enormous difference when investigating and making claims about network community structure, and it is important to take this into account to obtain reliable downstream conclusions. Depending on which scenario holds, one may or may not be able to successfully identify "good" communities in a given network (and good communities might not even exist for a given community quality measure), the manner in which different small communities fit together to form meso-scale network structures can be very different, and processes such as viral propagation and information diffusion can exhibit very different dynamics. In addition, our results suggest that, for many large realistic networks, the output of locally biased methods that focus on communities that are centered around a given seed node (or set of seed nodes) might have better conceptual grounding and greater practical utility than the output of global community-detection methods. They also illustrate structural properties that are important to consider in the development of better benchmark networks to test methods for community detection.

Think Locally, Act Locally: The Detection of Small, Medium-Sized, and Large Communities in Large Networks

PubMed Central

Jeub, Lucas G. S.; Balachandran, Prakash; Porter, Mason A.; Mucha, Peter J.; Mahoney, Michael W.

2016-01-01

It is common in the study of networks to investigate intermediate-sized (or “meso-scale”) features to try to gain an understanding of network structure and function. For example, numerous algorithms have been developed to try to identify “communities,” which are typically construed as sets of nodes with denser connections internally than with the remainder of a network. In this paper, we adopt a complementary perspective that “communities” are associated with bottlenecks of locally-biased dynamical processes that begin at seed sets of nodes, and we employ several different community-identification procedures (using diffusion-based and geodesic-based dynamics) to investigate community quality as a function of community size. Using several empirical and synthetic networks, we identify several distinct scenarios for “size-resolved community structure” that can arise in real (and realistic) networks: (i) the best small groups of nodes can be better than the best large groups (for a given formulation of the idea of a good community); (ii) the best small groups can have a quality that is comparable to the best medium-sized and large groups; and (iii) the best small groups of nodes can be worse than the best large groups. As we discuss in detail, which of these three cases holds for a given network can make an enormous difference when investigating and making claims about network community structure, and it is important to take this into account to obtain reliable downstream conclusions. Depending on which scenario holds, one may or may not be able to successfully identify “good” communities in a given network (and good communities might not even exist for a given community quality measure), the manner in which different small communities fit together to form meso-scale network structures can be very different, and processes such as viral propagation and information diffusion can exhibit very different dynamics. In addition, our results suggest that, for many large realistic networks, the output of locally-biased methods that focus on communities that are centered around a given seed node might have better conceptual grounding and greater practical utility than the output of global community-detection methods. They also illustrate subtler structural properties that are important to consider in the development of better benchmark networks to test methods for community detection. PMID:25679670

Think locally, act locally: Detection of small, medium-sized, and large communities in large networks

NASA Astrophysics Data System (ADS)

Jeub, Lucas G. S.; Balachandran, Prakash; Porter, Mason A.; Mucha, Peter J.; Mahoney, Michael W.

2015-01-01

It is common in the study of networks to investigate intermediate-sized (or "meso-scale") features to try to gain an understanding of network structure and function. For example, numerous algorithms have been developed to try to identify "communities," which are typically construed as sets of nodes with denser connections internally than with the remainder of a network. In this paper, we adopt a complementary perspective that communities are associated with bottlenecks of locally biased dynamical processes that begin at seed sets of nodes, and we employ several different community-identification procedures (using diffusion-based and geodesic-based dynamics) to investigate community quality as a function of community size. Using several empirical and synthetic networks, we identify several distinct scenarios for "size-resolved community structure" that can arise in real (and realistic) networks: (1) the best small groups of nodes can be better than the best large groups (for a given formulation of the idea of a good community); (2) the best small groups can have a quality that is comparable to the best medium-sized and large groups; and (3) the best small groups of nodes can be worse than the best large groups. As we discuss in detail, which of these three cases holds for a given network can make an enormous difference when investigating and making claims about network community structure, and it is important to take this into account to obtain reliable downstream conclusions. Depending on which scenario holds, one may or may not be able to successfully identify "good" communities in a given network (and good communities might not even exist for a given community quality measure), the manner in which different small communities fit together to form meso-scale network structures can be very different, and processes such as viral propagation and information diffusion can exhibit very different dynamics. In addition, our results suggest that, for many large realistic networks, the output of locally biased methods that focus on communities that are centered around a given seed node (or set of seed nodes) might have better conceptual grounding and greater practical utility than the output of global community-detection methods. They also illustrate structural properties that are important to consider in the development of better benchmark networks to test methods for community detection.

Preliminary report on social psychological factors in long duration space flights: Review and directions for future research

NASA Technical Reports Server (NTRS)

Harrison, A. A.

1978-01-01

Group dynamics, sociological and psychological factors are examined. Crew composition and compatibility are studied. Group dynamics analysis includes: leadership; cohesiveness; conformity; and conflict.

Advances in Remote Sensing for Vegetation Dynamics and Agricultural Management

NASA Technical Reports Server (NTRS)

Tucker, Compton; Puma, Michael

2015-01-01

Spaceborne remote sensing has led to great advances in the global monitoring of vegetation. For example, the NASA Global Inventory Modeling and Mapping Studies (GIMMS) group has developed widely used datasets from the Advanced Very High Resolution Radiometer (AVHRR) sensors as well as the Moderate Resolution Imaging Spectroradiometer (MODIS) map imagery and normalized difference vegetation index datasets. These data are valuable for analyzing vegetation trends and variability at the regional and global levels. Numerous studies have investigated such trends and variability for both natural vegetation (e.g., re-greening of the Sahel, shifts in the Eurasian boreal forest, Amazonian drought sensitivity) and crops (e.g., impacts of extremes on agricultural production). Here, a critical overview is presented on recent developments and opportunities in the use of remote sensing for monitoring vegetation and crop dynamics.

Development of a potent 2-oxoamide inhibitor of secreted phospholipase A2 guided by molecular docking calculations and molecular dynamics simulations

PubMed Central

Vasilakaki, Sofia; Barbayianni, Efrosini; Leonis, Georgios; Papadopoulos, Manthos G.; Mavromoustakos, Thomas; Gelb, Michael H.; Kokotos, George

2016-01-01

Inhibition of group IIA secreted phospholipase A2 (GIIA sPLA2) has been an important objective for medicinal chemists. We have previously shown that inhibitors incorporating the 2-oxoamide functionality may inhibit human and mouse GIIA sPLA2s. Herein, the development of new potent inhibitors by molecular docking calculations using the structure of the known inhibitor 7 as scaffold, are described. Synthesis and biological evaluation of the new compounds revealed that the long chain 2-oxoamide based on (S)-valine GK241 led to improved activity (IC50 = 143 nM and 68 nM against human and mouse GIIA sPLA2, respectively). In addition, molecular dynamics simulations were employed to shed light on GK241 potent and selective inhibitory activity. PMID:26970660

Spectra- and temperature-dependent dynamics of directly end-pumped holmium lasers

NASA Astrophysics Data System (ADS)

Ji, Encai; Shen, Yijie; Nie, Mingming; Fu, Xing; Liu, Qiang

2017-04-01

We develop a theoretical model with high accuracy for directly end-pumped Ho3+ laser system considering the influences of ground-state depletion, energy transfer up-conversion, temperature-dependent cross sections, and pump spectra shift. The heat generation in our model is precisely evaluated by calculating the transition rates of non-radiation relaxation processes among manifolds and in-band relaxation processes based on a detailed analysis of energy levels structure of holmium ions. A spatial dynamic thermal iteration method, just developed by our group, is applied to describe the coupled influences between spatial thermal effects and pump spectra. This model is verified to both adapt to the narrow-band good beam-quality pumped case and the broad-band bad beam-quality pumped case, which is in accordance with our previous reported experimental results.

Development of atomic force microscope with wide-band magnetic excitation for study of soft matter dynamics

NASA Astrophysics Data System (ADS)

Kageshima, Masami; Chikamoto, Takuma; Ogawa, Tatsuya; Hirata, Yoshiki; Inoue, Takahito; Naitoh, Yoshitaka; Li, Yan Jun; Sugawara, Yasuhiro

2009-02-01

In order to probe dynamical properties of mesoscopic soft matter systems such as polymers, structured liquid, etc., a new atomic force microscopy apparatus with a wide-band magnetic cantilever excitation system was developed. Constant-current driving of an electromagnet up to 1 MHz was implemented with a closed-loop driver circuit. Transfer function of a commercial cantilever attached with a magnetic particle was measured in a frequency range of 1-1000 kHz in distilled water. Effects of the laser spot position, distribution of the force exerted on the cantilever, and difference in the detection scheme on the obtained transfer function are discussed in comparison with theoretical predictions by other research groups. A preliminary result of viscoelasticity spectrum measurement of a single dextran chain is shown and is compared with a recent theoretical calculation.

Development of feedforward control in a dynamic manual tracking task.

PubMed

van Roon, Dominique; Caeyenberghs, Karen; Swinnen, Stephan P; Smits-Engelsman, Bouwien C M

2008-01-01

To examine the development of feedforward control during manual tracking, 117 participants in 5 age groups (6 to 7, 8 to 9, 10 to 11, 12 to 14, and 15 to 17 years) tracked an accelerating dot presented on a monitor by moving an electronic pen on a digitizer. To remain successful at higher target velocities, they had to create a predictive model of the target's motion. The ability to track the target at higher velocities increased, and the application of a feedback-based step-and-hold strategy decreased with age, as shown by increases in maximum target velocity and decreases in number of stops between ages 6-7 and 8-9 and between ages 8-9 and 10-11. The ability to exploit feedforward control in a dynamic tracking task improves significantly with age.

A Saccade Based Framework for Real-Time Motion Segmentation Using Event Based Vision Sensors

PubMed Central

Mishra, Abhishek; Ghosh, Rohan; Principe, Jose C.; Thakor, Nitish V.; Kukreja, Sunil L.

2017-01-01

Motion segmentation is a critical pre-processing step for autonomous robotic systems to facilitate tracking of moving objects in cluttered environments. Event based sensors are low power analog devices that represent a scene by means of asynchronous information updates of only the dynamic details at high temporal resolution and, hence, require significantly less calculations. However, motion segmentation using spatiotemporal data is a challenging task due to data asynchrony. Prior approaches for object tracking using neuromorphic sensors perform well while the sensor is static or a known model of the object to be followed is available. To address these limitations, in this paper we develop a technique for generalized motion segmentation based on spatial statistics across time frames. First, we create micromotion on the platform to facilitate the separation of static and dynamic elements of a scene, inspired by human saccadic eye movements. Second, we introduce the concept of spike-groups as a methodology to partition spatio-temporal event groups, which facilitates computation of scene statistics and characterize objects in it. Experimental results show that our algorithm is able to classify dynamic objects with a moving camera with maximum accuracy of 92%. PMID:28316563

Poly-proline-based chiral stationary phases: a molecular dynamics study of triproline, tetraproline, pentaproline and hexaproline interfaces.

PubMed

Ashtari, M; Cann, N M

2012-11-23

Poly-proline chains and derivatives have been recently examined as the basis for new chiral stationary phases in high performance liquid chromatography. The selectivity of poly-proline has been measured for peptides with up to ten proline units. In this article, we employ molecular dynamics simulations to examine the interfacial structure and solvation of surface-bound poly-proline chiral selectors. Specifically, we study the interfacial structure of trimethylacetyl-terminated poly-proline chains with three-to-six prolines. The surface includes silanol groups and end-caps, to better capture the characteristics of the stationary phase, and the solvent is either a polar water/methanol or a relatively apolar n-hexane/2-propanol mixture. We begin with a comprehensive ab initio study of the conformers, their energies, and an assessment of conformer flexibility. Force fields have been developed for each poly-proline selector. Molecular dynamics simulations are employed to study the preferred backbone conformations and solvent hydrogen bonding for different poly-proline/solvent interfaces. For triproline, the effect of two different terminal groups, trimethylacetyl and t-butyl carbamate are compared. Copyright © 2012 Elsevier B.V. All rights reserved.

Efficacy of guided spiral drawing in the classification of Parkinson's Disease.

PubMed

Zham, Poonam; Arjunan, Sridhar; Raghav, Sanjay; Kumar, Dinesh Kant

2017-10-11

Change of handwriting can be an early marker for severity of Parkinson's disease but suffers from poor sensitivity and specificity due to inter-subject variations. This study has investigated the group-difference in the dynamic features during sketching of spiral between PD and control subjects with the aim of developing an accurate method for diagnosing PD patients. Dynamic handwriting features were computed for 206 specimens collected from 62 Subjects (31 Parkinson's and 31 Controls). These were analyzed based on the severity of the disease to determine group-difference. Spearman rank correlation coefficient was computed to evaluate the strength of association for the different features. Maximum area under ROC curve (AUC) using the dynamic features during different writing and spiral sketching tasks were in the range of 67 to 79 %. However, when angular features ( and ) and count of direction inversion during sketching of the spiral were used, AUC improved to 93.3%. Spearman correlation coefficient was highest for and . The angular features and count of direction inversion which can be obtained in real-time while sketching the Archimedean guided spiral on a digital tablet can be used for differentiating between Parkinson's and healthy cohort.

Efficacy of identifying neural components in the face and emotion processing system in schizophrenia using a dynamic functional localizer.

PubMed

Arnold, Aiden E G F; Iaria, Giuseppe; Goghari, Vina M

2016-02-28

Schizophrenia is associated with deficits in face perception and emotion recognition. Despite consistent behavioural results, the neural mechanisms underlying these cognitive abilities have been difficult to isolate, in part due to differences in neuroimaging methods used between studies for identifying regions in the face processing system. Given this problem, we aimed to validate a recently developed fMRI-based dynamic functional localizer task for use in studies of psychiatric populations and specifically schizophrenia. Previously, this functional localizer successfully identified each of the core face processing regions (i.e. fusiform face area, occipital face area, superior temporal sulcus), and regions within an extended system (e.g. amygdala) in healthy individuals. In this study, we tested the functional localizer success rate in 27 schizophrenia patients and in 24 community controls. Overall, the core face processing regions were localized equally between both the schizophrenia and control group. Additionally, the amygdala, a candidate brain region from the extended system, was identified in nearly half the participants from both groups. These results indicate the effectiveness of a dynamic functional localizer at identifying regions of interest associated with face perception and emotion recognition in schizophrenia. The use of dynamic functional localizers may help standardize the investigation of the facial and emotion processing system in this and other clinical populations. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Modeling and Bio molecular Self-assembly via Molecular Dynamics and Dissipative Particle Dynamics

NASA Astrophysics Data System (ADS)

Rakesh, L.

2009-09-01

Surfactants like materials can be used to increase the solubility of poorly soluble drugs in water and to increase drug bioavailability. A typical case study will be demonstrated using DPD simulation to model the distribution of anti-inflammatory drug molecules. Computer simulation is a convenient approach to understand drug distribution and solubility concepts without much wastage and costly experiments in the laboratory. Often in molecular dynamics (MD) the atoms are represented explicitly and the equation of motion as described by Newtonian dynamics is integrated explicitly. MD has been used to study spontaneous formation of micelles by hydrophobic molecules with amphiphilic head groups in bulk water, as well as stability of pre-configured micelles and membranes. DPD is a state-of the- art mesoscale simulation, it is a more recent molecular dynamics technique, originally developed for simulating complex fluids but lately also applied to membrane dynamics, hemodynamic in biomedical applications. Such fluids pervade industrial research from paints to pharmaceuticals and from cosmetics to the controlled release of drugs. Dissipative particle dynamics (DPD) can provide structural and dynamic properties of fluids in equilibrium, under shear or confined to narrow cavities, at length- and time-scales beyond the scope of traditional atomistic molecular dynamics simulation methods. Mesoscopic particles are used to represent clusters of molecules. The interaction conserves mass and momentum and as a consequence the dynamics is consistent with Navier-Stokes equations. In addition to the conservative forces, stochastic drive and dissipation is introduced to represent internal degrees of freedom in the mesoscopic particles. In this research, an initial study is being conducted using the aqueous solubilization of the nonsteroidal, anti-inflammatory drug is studied theoretically in micellar solution of nonionic (dodecyl hexa(ethylene oxide), C12E6) surfactants possessing the hydrocarbon "tail" and their hydrophilic head groups. We find that, for the surfactants, the aqueous solubility of anti-inflammatory molecules increases linearly with increasing surfactant concentration. In particular, we observed a 10-fold increase in the solubility of anti-inflammatory drugs relative to that in the aqueous buffer upon the addition of 100 mM dodecyltrimethyl ammonium bromide -DTAB.

From Geometry Optimization to Time Dependent Molecular Structure Modeling: Method Developments, ab initio Theories and Applications

NASA Astrophysics Data System (ADS)

Liang, Wenkel

This dissertation consists of two general parts: (I) developments of optimization algorithms (both nuclear and electronic degrees of freedom) for time-independent molecules and (II) novel methods, first-principle theories and applications in time dependent molecular structure modeling. In the first part, we discuss in specific two new algorithms for static geometry optimization, the eigenspace update (ESU) method in nonredundant internal coordinate that exhibits an enhanced performace with up to a factor of 3 savings in computational cost for large-sized molecular systems; the Car-Parrinello density matrix search (CP-DMS) method that enables direct minimization of the SCF energy as an effective alternative to conventional diagonalization approach. For the second part, we consider the time dependence and first presents two nonadiabatic dynamic studies that model laser controlled molecular photo-dissociation for qualitative understandings of intense laser-molecule interaction, using ab initio direct Ehrenfest dynamics scheme implemented with real-time time-dependent density functional theory (RT-TDDFT) approach developed in our group. Furthermore, we place our special interest on the nonadiabatic electronic dynamics in the ultrafast time scale, and presents (1) a novel technique that can not only obtain energies but also the electron densities of doubly excited states within a single determinant framework, by combining methods of CP-DMS with RT-TDDFT; (2) a solvated first-principles electronic dynamics method by incorporating the polarizable continuum solvation model (PCM) to RT-TDDFT, which is found to be very effective in describing the dynamical solvation effect in the charge transfer process and yields a consistent absorption spectrum in comparison to the conventional linear response results in solution. (3) applications of the PCM-RT-TDDFT method to study the intramolecular charge-transfer (CT) dynamics in a C60 derivative. Such work provides insights into the characteristics of ultrafast dynamics in photoexcited fullerene derivatives, and aids in the rational design for pre-dissociative exciton in the intramolecular CT process in organic solar cells.

The effects of a multisensory dynamic balance training on the thickness of lower limb muscles in ultrasonography in children with spastic diplegic cerebral palsy.

PubMed

Nam, Seung-Min; Kim, Won-Hyo; Yun, Chang-Kyo

2017-04-01

[Purpose] This study aimed to investigate the effects of multisensory dynamic balance training on muscles thickness such as rectus femoris, anterior tibialis, medial gastrocnemius, lateral gastrocnemius in children with spastic diplegic cerebral palsy by using ultrasonography. [Subjects and Methods] Fifteen children diagnosed with spastic diplegic cerebral palsy were divided randomly into the balance training group and control group. The experimental group only received a multisensory dynamic balance training, while the control group performed general physiotherapy focused balance and muscle strengthening exercise based Neurodevelopmental treatment. Both groups had a therapy session for 30 minutes per day, three times a week for six weeks. The ultrasonographic muscle thickness were obtained in order to compare and analyze muscle thickness before and after in each group. [Result] The experimental group had significant increases in muscle thickness in the rectus femoris, tibialis anterior, medial gastrocnemius and lateral gastrocnemius muscles. The control group had significant increases in muscle thickness in the tibialis anterior. The test results of the rectus femoris, medial gastrocnemius and lateral gastrocnemius muscle thickness values between the groups showed significant differences. [Conclusion] In conclusion, a multisensory dynamic balance training can be recommended as a treatment method for patients with spastic diplegic cerebral palsy.

Methods and analysis of realizing randomized grouping.

PubMed

Hu, Liang-Ping; Bao, Xiao-Lei; Wang, Qi

2011-07-01

Randomization is one of the four basic principles of research design. The meaning of randomization includes two aspects: one is to randomly select samples from the population, which is known as random sampling; the other is to randomly group all the samples, which is called randomized grouping. Randomized grouping can be subdivided into three categories: completely, stratified and dynamically randomized grouping. This article mainly introduces the steps of complete randomization, the definition of dynamic randomization and the realization of random sampling and grouping by SAS software.

First-Year Student Experiences in Community College: Making Transitions, Forming Connections, and Developing Perceptions of Student Learning. Draft.

ERIC Educational Resources Information Center

Jalomo, Romero Espinoza, Jr.

This paper provides theoretical background and methodology for a focus group study of influences on first-time Latino community college students. The first chapter identifies the need for research on Latino students, citing high attrition rates and focusing on three critical dynamics: making the transition to college, making connections on campus…

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

ERIC Educational Resources Information Center

Kulesza, Ewa Maria

2015-01-01

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

Walking the Razor's Edge: Risks and Rewards for Students and Faculty Adopting Case in Point Teaching and Learning Approaches

ERIC Educational Resources Information Center

Wildermuth, Cristina de-Mello-e-Souza; Smith-Bright, Elaine; Noll-Wilson, Sarah; Fink, Alex

2015-01-01

Case in Point (CIP) is an interactive leadership development method pioneered by Ronald Heifetz. CIP instructors follow a fluid class structure, in which group dynamics and student concerns become catalysts for learning. CIP proponents defend the method's potential to help students experience real life leadership challenges. To date, however, very…

How to Organize a Community Assembly Based on a New England Town Meeting Format: A Technique for Determining Community Priorities.

ERIC Educational Resources Information Center

Bolton Inst., Inc., Wellesley, MA.

This model, developed and tested in Vermont, involved a two-day assembly using a technique concentrating on small-group dynamics to encourage productive community assessment and decision-making. Included are exhaustive documentation of an example assembly to consider options for integrating human and environmental requirements in Vermont as a…

Radar Orbit Analysis Tool Using Least Squares Estimator

DTIC Science & Technology

2007-09-01

g gravity................................................................................................ km/s2 bodyg −2 v gravity due to two ...motion, it is necessary to determine how the dynamics between the two groups differ. One solution is to develop a model that can detect non...with just J2 and two -body terms was also addressed. Methodology Solving the estimation problem required dividing the process into four stages

Structure and Dynamics of Hydroxyl-Functionalized Protic Ammonium Carboxylate Ionic Liquids.

PubMed

Thummuru, Dhileep Nagi Reddy; Mallik, Bhabani S

2017-10-26

We performed classical molecular dynamics simulations to investigate the structure and dynamics of protic ionic liquids, 2-hydroxy ethylammonium acetate, ethylammonium hydroxyacetate, and 2-hydroxyethylammonium hydroxyacetate at ambient conditions. Structural properties such as density, radial distribution functions, spatial distribution functions, and structure factors have been calculated. Dynamic properties such as mean square displacements, as well as residence and hydrogen bond dynamics have also been calculated. Hydrogen bond lifetimes and residence times change with the addition of hydroxyl groups. We observe that when a hydroxyl group is present on the cation, dynamics become very slow and it forms a strong hydrogen bond with carboxylate oxygen atoms of the anion. The hydroxyl functionalized ILs show more dynamic diversity than structurally similar ILs.

Biomechanical assessment of dynamic balance: Specificity of different balance tests.

PubMed

Ringhof, Steffen; Stein, Thorsten

2018-04-01

Dynamic balance is vitally important for most sports and activities of daily living, so the assessment of dynamic stability has become an important issue. In consequence, a large number of balance tests have been developed. However, it is not yet known whether these tests (i) measure the same construct and (ii) can differentiate between athletes with different balance expertise. We therefore studied three common dynamic balance tests: one-leg jump landings, Posturomed perturbations and simulated forward falls. Participants were 24 healthy young females in regular training in either gymnastics (n = 12) or swimming (n = 12). In each of the tests, the participants were instructed to recover balance as quickly as possible. Dynamic stability was computed by time to stabilization and margin of stability, deduced from force plates and motion capture respectively. Pearson's correlations between the dynamic balance tests found no significant associations between the respective dynamic stability measures. Furthermore, independent t-tests indicated that only jump landings could properly distinguish between both groups of athletes. In essence, the different dynamic balance tests applied did not measure the same construct but rather task-specific skills, each of which depends on multifactorial internal and external constraints. Our study therefore contradicts the traditional view of considering balance as a general ability, and reinforces that dynamic balance measures are not interchangeable. This highlights the importance of selecting appropriate balance tests. Copyright © 2018 Elsevier B.V. All rights reserved.

Human Health and Climate Change: Leverage Points for Adaptation in Urban Environments

PubMed Central

Proust, Katrina; Newell, Barry; Brown, Helen; Capon, Anthony; Browne, Chris; Burton, Anthony; Dixon, Jane; Mu, Lisa; Zarafu, Monica

2012-01-01

The design of adaptation strategies that promote urban health and well-being in the face of climate change requires an understanding of the feedback interactions that take place between the dynamical state of a city, the health of its people, and the state of the planet. Complexity, contingency and uncertainty combine to impede the growth of such systemic understandings. In this paper we suggest that the collaborative development of conceptual models can help a group to identify potential leverage points for effective adaptation. We describe a three-step procedure that leads from the development of a high-level system template, through the selection of a problem space that contains one or more of the group’s adaptive challenges, to a specific conceptual model of a sub-system of importance to the group. This procedure is illustrated by a case study of urban dwellers’ maladaptive dependence on private motor vehicles. We conclude that a system dynamics approach, revolving around the collaborative construction of a set of conceptual models, can help communities to improve their adaptive capacity, and so better meet the challenge of maintaining, and even improving, urban health in the face of climate change. PMID:22829795

Visualization of Atmospheric Water Vapor Data for SAGE

NASA Technical Reports Server (NTRS)

Kung, Mou-Liang; Chu, W. P. (Technical Monitor)

2000-01-01

The goal of this project was to develop visualization tools to study the water vapor dynamics using the Stratospheric Aerosol and Gas Experiment 11 (SAGE 11) water vapor data. During the past years, we completed the development of a visualization tool called EZSAGE, and various Gridded Water Vapor plots, tools deployed on the web to provide users with new insight into the water vapor dynamics. Results and experiences from this project, including papers, tutorials and reviews were published on the main Web page. Additional publishing effort has been initiated to package EZSAGE software for CD production and distribution. There have been some major personnel changes since Fall, 1998. Dr. Mou-Liang Kung, a Professor of Computer Science assumed the PI position vacated by Dr. Waldo Rodriguez who was on leave. However, former PI, Dr. Rodriguez continued to serve as a research adviser to this project to assure smooth transition and project completion. Typically in each semester, five student research assistants were hired and trained. Weekly group meetings were held to discuss problems, progress, new research direction, and activity planning. Other small group meetings were also held regularly for different objectives of this project. All student research assistants were required to submit reports for conference submission.

Dynamic feature analysis of vector-based images for neuropsychological testing

NASA Astrophysics Data System (ADS)

Smith, Stephen L.; Cervantes, Basilio R.

1998-07-01

The dynamic properties of human motor activities, such as those observed in the course of drawing simple geometric shapes, are considerably more complex and often more informative than the goal to be achieved; in this case a static line drawing. This paper demonstrates how these dynamic properties may be used to provide a means of assessing a patient's visuo-spatial ability -- an important component of neuropsychological testing. The work described here provides a quantitative assessment of visuo-spatial ability, whilst preserving the conventional test environment. Results will be presented for a clinical population of long-term haemodialysis patients and test population comprises three groups of children (1) 7-8 years, (2) 9-10 years and (3) 11-12 years, all of which have no known neurological dysfunction. Ten new dynamic measurements extracted from patient responses in conjunction with one static feature deduced from earlier work describe a patient's visuo-spatial ability in a quantitative manner with sensitivity not previously attainable. The dynamic feature measurements in isolation provide a unique means of tracking a patient's approach to motor activities and could prove useful in monitoring a child' visuo-motor development.

Visual masking and the dynamics of human perception, cognition, and consciousness A century of progress, a contemporary synthesis, and future directions.

PubMed

Ansorge, Ulrich; Francis, Gregory; Herzog, Michael H; Oğmen, Haluk

2008-07-15

The 1990s, the "decade of the brain," witnessed major advances in the study of visual perception, cognition, and consciousness. Impressive techniques in neurophysiology, neuroanatomy, neuropsychology, electrophysiology, psychophysics and brain-imaging were developed to address how the nervous system transforms and represents visual inputs. Many of these advances have dealt with the steady-state properties of processing. To complement this "steady-state approach," more recent research emphasized the importance of dynamic aspects of visual processing. Visual masking has been a paradigm of choice for more than a century when it comes to the study of dynamic vision. A recent workshop (http://lpsy.epfl.ch/VMworkshop/), held in Delmenhorst, Germany, brought together an international group of researchers to present state-of-the-art research on dynamic visual processing with a focus on visual masking. This special issue presents peer-reviewed contributions by the workshop participants and provides a contemporary synthesis of how visual masking can inform the dynamics of human perception, cognition, and consciousness.

Visual masking and the dynamics of human perception, cognition, and consciousness A century of progress, a contemporary synthesis, and future directions

PubMed Central

Ansorge, Ulrich; Francis, Gregory; Herzog, Michael H.; Öğmen, Haluk

2008-01-01

The 1990s, the “decade of the brain,” witnessed major advances in the study of visual perception, cognition, and consciousness. Impressive techniques in neurophysiology, neuroanatomy, neuropsychology, electrophysiology, psychophysics and brain-imaging were developed to address how the nervous system transforms and represents visual inputs. Many of these advances have dealt with the steady-state properties of processing. To complement this “steady-state approach,” more recent research emphasized the importance of dynamic aspects of visual processing. Visual masking has been a paradigm of choice for more than a century when it comes to the study of dynamic vision. A recent workshop (http://lpsy.epfl.ch/VMworkshop/), held in Delmenhorst, Germany, brought together an international group of researchers to present state-of-the-art research on dynamic visual processing with a focus on visual masking. This special issue presents peer-reviewed contributions by the workshop participants and provides a contemporary synthesis of how visual masking can inform the dynamics of human perception, cognition, and consciousness. PMID:20517493

Dynamics and Novel Mechanisms of SN2 Reactions on ab Initio Analytical Potential Energy Surfaces.

PubMed

Szabó, István; Czakó, Gábor

2017-11-30

We describe a novel theoretical approach to the bimolecular nucleophilic substitution (S N 2) reactions that is based on analytical potential energy surfaces (PESs) obtained by fitting a few tens of thousands high-level ab initio energy points. These PESs allow computing millions of quasi-classical trajectories thereby providing unprecedented statistical accuracy for S N 2 reactions, as well as performing high-dimensional quantum dynamics computations. We developed full-dimensional ab initio PESs for the F - + CH 3 Y [Y = F, Cl, I] systems, which describe the direct and indirect, complex-forming Walden-inversion, the frontside attack, and the new double-inversion pathways as well as the proton-transfer channels. Reaction dynamics simulations on the new PESs revealed (a) a novel double-inversion S N 2 mechanism, (b) frontside complex formation, (c) the dynamics of proton transfer, (d) vibrational and rotational mode specificity, (e) mode-specific product vibrational distributions, (f) agreement between classical and quantum dynamics, (g) good agreement with measured scattering angle and product internal energy distributions, and (h) significant leaving group effect in accord with experiments.

The Dynamical Core Model Intercomparison Project (DCMIP-2016): Results of the Supercell Test Case

NASA Astrophysics Data System (ADS)

Zarzycki, C. M.; Reed, K. A.; Jablonowski, C.; Ullrich, P. A.; Kent, J.; Lauritzen, P. H.; Nair, R. D.

2016-12-01

The 2016 Dynamical Core Model Intercomparison Project (DCMIP-2016) assesses the modeling techniques for global climate and weather models and was recently held at the National Center for Atmospheric Research (NCAR) in conjunction with a two-week summer school. Over 12 different international modeling groups participated in DCMIP-2016 and focused on the evaluation of the newest non-hydrostatic dynamical core designs for future high-resolution weather and climate models. The paper highlights the results of the third DCMIP-2016 test case, which is an idealized supercell storm on a reduced-radius Earth. The supercell storm test permits the study of a non-hydrostatic moist flow field with strong vertical velocities and associated precipitation. This test assesses the behavior of global modeling systems at extremely high spatial resolution and is used in the development of next-generation numerical weather prediction capabilities. In this regime the effective grid spacing is very similar to the horizontal scale of convective plumes, emphasizing resolved non-hydrostatic dynamics. The supercell test case sheds light on the physics-dynamics interplay and highlights the impact of diffusion on model solutions.

[Dynamic vision of sportsmen with different requirement profiles for the visual apparatus].

PubMed

Lüder, A; Andexer, V; Witte, K; Böckelmann, I

2011-12-01

In particular, in the quick ball and racket games a good dynamic seeing is required . The afferent dynamic seeing occurs via the retiina which mediates the stimuli for efferent dynamic seeing . The aim of this study was to examine the dynamic visual acuity of sportsmen from sports with different demands on their dynamic seeing (DS). 19 sports students took part in the study. 10 subjects participated in coached team sports (group I) and 9 remaining performed individual sports (group II). The DS was assessed by means of the Düsseldorfer test for dynamic seeing of Wist which was performed twice on one day. The DS of the two groups in the first study did not differ (right eye 95.7 ± 10.6 % in group I vs. 94.3 ± 6.9 % in group II and left eye 97.6 ± 4.8 % vs. 95.3 ± 5.6 %; p ≥ 0.05). Also the second study there was no different in DS for the two groups (right eye 98.3 ± 2.6 % vs. 93.8 ± 8.0 % and left eye 99.3 ± 1.2 % vs. 95.6 ± 7.0 %; p ≥ 0.05). Our hypothesis about a different DS in players of ball games compared with non-ball sport players could not be proved. It is to be critically noted that a generalization is not possible due to the small sample numbers. Because DS is a necessary precondition in ball games further studies should be concentrated on its trainability. © Georg Thieme Verlag KG Stuttgart · New York.

Modeling Tools for Propulsion Analysis and Computational Fluid Dynamics on the Internet

NASA Technical Reports Server (NTRS)

Muss, J. A.; Johnson, C. W.; Gotchy, M. B.

2000-01-01

The existing RocketWeb(TradeMark) Internet Analysis System (httr)://www.iohnsonrockets.com/rocketweb) provides an integrated set of advanced analysis tools that can be securely accessed over the Internet. Since these tools consist of both batch and interactive analysis codes, the system includes convenient methods for creating input files and evaluating the resulting data. The RocketWeb(TradeMark) system also contains many features that permit data sharing which, when further developed, will facilitate real-time, geographically diverse, collaborative engineering within a designated work group. Adding work group management functionality while simultaneously extending and integrating the system's set of design and analysis tools will create a system providing rigorous, controlled design development, reducing design cycle time and cost.

Social defense: an evolutionary-developmental model of children's strategies for coping with threat in the peer group.

PubMed

Martin, Meredith J; Davies, Patrick T; MacNeill, Leigha A

2014-04-29

Navigating the ubiquitous conflict, competition, and complex group dynamics of the peer group is a pivotal developmental task of childhood. Difficulty negotiating these challenges represents a substantial source of risk for psychopathology. Evolutionary developmental psychology offers a unique perspective with the potential to reorganize the way we think about the role of peer relationships in shaping how children cope with the everyday challenges of establishing a social niche. To address this gap, we utilize the ethological reformulation of the emotional security theory as a guide to developing an evolutionary framework for advancing an understanding of the defense strategies children use to manage antagonistic peer relationships and protect themselves from interpersonal threat (Davies and Sturge-Apple, 2007). In this way, we hope to illustrate the value of an evolutionary developmental lens in generating unique theoretical insight and novel research directions into the role of peer relationships in the development of psychopathology.

WikiBuild: a new online collaboration process for multistakeholder tool development and consensus building.

PubMed

Gupta, Samir; Wan, Flora T; Newton, David; Bhattacharyya, Onil K; Chignell, Mark H; Straus, Sharon E

2011-12-08

Production of media such as patient education tools requires methods that can integrate multiple stakeholder perspectives. Existing consensus techniques are poorly suited to design of visual media, can be expensive and logistically demanding, and are subject to caveats arising from group dynamics such as participant hierarchies. Our objective was to develop a method that enables multistakeholder tool building while averting these difficulties. We developed a wiki-inspired method and tested this through the collaborative design of an asthma action plan (AAP). In the development stage, we developed the Web-based tool by (1) establishing AAP content and format options, (2) building a Web-based application capable of representing each content and format permutation, (3) testing this tool among stakeholders, and (4) revising this tool based on stakeholder feedback. In the wiki stage, groups of participants used the revised tool in three separate 1-week "wiki" periods during which each group collaboratively authored an AAP by making multiple online selections. In the development stage, we recruited 16 participants (9/16 male) (4 pulmonologists, 4 primary care physicians, 3 certified asthma educators, and 5 patients) for system testing. The mean System Usability Scale (SUS) score for the tool used in testing was 72.2 (SD 10.2). In the wiki stage, we recruited 41 participants (15/41 male) (9 pulmonologists, 6 primary care physicians, 5 certified asthma educators, and 21 patients) from diverse locations. The mean SUS score for the revised tool was 75.9 (SD 19.6). Users made 872, 466, and 599 successful changes to the AAP in weeks 1, 2, and 3, respectively. The site was used actively for a mean of 32.0 hours per week, of which 3.1 hours per week (9.7%) constituted synchronous multiuser use (2-4 users at the same time). Participants averaged 23 (SD 33) minutes of login time and made 7.7 (SD 15) changes to the AAP per day. Among participants, 28/35 (80%) were satisfied with the final AAP, and only 3/34 (9%) perceived interstakeholder group hierarchies. Use of a wiki-inspired method allowed for effective collaborative design of content and format aspects of an AAP while minimizing logistical requirements, maximizing geographical representation, and mitigating hierarchical group dynamics. Our method faced unique software and hardware challenges, and raises certain questions regarding its effect on group functioning. Potential uses of our method are broad, and further studies are required.

WikiBuild: A New Online Collaboration Process For Multistakeholder Tool Development and Consensus Building

PubMed Central

Wan, Flora T; Newton, David; Bhattacharyya, Onil K; Chignell, Mark H; Straus, Sharon E

2011-01-01

Background Production of media such as patient education tools requires methods that can integrate multiple stakeholder perspectives. Existing consensus techniques are poorly suited to design of visual media, can be expensive and logistically demanding, and are subject to caveats arising from group dynamics such as participant hierarchies. Objective Our objective was to develop a method that enables multistakeholder tool building while averting these difficulties. Methods We developed a wiki-inspired method and tested this through the collaborative design of an asthma action plan (AAP). In the development stage, we developed the Web-based tool by (1) establishing AAP content and format options, (2) building a Web-based application capable of representing each content and format permutation, (3) testing this tool among stakeholders, and (4) revising this tool based on stakeholder feedback. In the wiki stage, groups of participants used the revised tool in three separate 1-week “wiki” periods during which each group collaboratively authored an AAP by making multiple online selections. Results In the development stage, we recruited 16 participants (9/16 male) (4 pulmonologists, 4 primary care physicians, 3 certified asthma educators, and 5 patients) for system testing. The mean System Usability Scale (SUS) score for the tool used in testing was 72.2 (SD 10.2). In the wiki stage, we recruited 41 participants (15/41 male) (9 pulmonologists, 6 primary care physicians, 5 certified asthma educators, and 21 patients) from diverse locations. The mean SUS score for the revised tool was 75.9 (SD 19.6). Users made 872, 466, and 599 successful changes to the AAP in weeks 1, 2, and 3, respectively. The site was used actively for a mean of 32.0 hours per week, of which 3.1 hours per week (9.7%) constituted synchronous multiuser use (2–4 users at the same time). Participants averaged 23 (SD 33) minutes of login time and made 7.7 (SD 15) changes to the AAP per day. Among participants, 28/35 (80%) were satisfied with the final AAP, and only 3/34 (9%) perceived interstakeholder group hierarchies. Conclusion Use of a wiki-inspired method allowed for effective collaborative design of content and format aspects of an AAP while minimizing logistical requirements, maximizing geographical representation, and mitigating hierarchical group dynamics. Our method faced unique software and hardware challenges, and raises certain questions regarding its effect on group functioning. Potential uses of our method are broad, and further studies are required. PMID:22155694

Two-actor conflict with time delay: A dynamical model

NASA Astrophysics Data System (ADS)

Qubbaj, Murad R.; Muneepeerakul, Rachata

2012-11-01

Recent mathematical dynamical models of the conflict between two different actors, be they nations, groups, or individuals, have been developed that are capable of predicting various outcomes depending on the chosen feedback strategies, initial conditions, and the previous states of the actors. In addition to these factors, this paper examines the effect of time delayed feedback on the conflict dynamics. Our analysis shows that under certain initial and feedback conditions, a stable neutral equilibrium of conflict may destabilize for some critical values of time delay, and the two actors may evolve to new emotional states. We investigate the results by constructing critical delay surfaces for different sets of parameters and analyzing results from numerical simulations. These results provide new insights regarding conflict and conflict resolution and may help planners in adjusting and assessing their strategic decisions.

Dynamics of biochemical components, lipid classes and energy values on gonadal development of R. philippinarum associated with the temperature and ingestion rate.

PubMed

Fernández-Reiriz, M J; Pérez-Camacho, A; Delgado, M; Labarta, U

2007-08-01

This study evaluates the effect of temperature, coupled with ingestion rate, on the dynamics of biochemical components and lipid classes in R. philippinarum. The data are discussed with regard to sexual development and energy balance. Experimental protocol developed in the present study used two groups of the clam R. philippinarum: L (temperatures of 14 degrees C and 18 degrees C) and H (temperatures of 18 degrees C and 22 degrees C). The intra-group ingestion level was similar, although the ingestion level of the clams in the group H was 2.4 times higher than group L. We observed that R. philippinarum conditioned at 18 degrees C (18L) shows higher protein content, furthermore an important loss of organic weight was observed after 48 days. In such a situation, the clams use their own reserves (carbohydrates and glycogen) for sexual development while in situations without food stress (positive energy balance) and low temperature (14 degrees C) an accumulation of reserves is produced. Strikingly dissimilar behaviour in biochemical composition was observed for the 18H and 22H treatments, both with a positive energy balance. Despite similar protein content, the highest levels of carbohydrates were observed at the lower temperature (18 degrees C). Glycogen was also higher for the 18 degrees C treatment, although the differences were significant only in the males. Although the total lipids in R. philippinarum showed no significant differences in any treatment, they became apparent and related to sex when considering the individual lipid classes. There was no variation in lipid classes in the males between the 14L and 22H treatments despite the large disparity in the degree of sexual development. However, in the females significant differences in lipid classes (phospholipids, triglycerides) were observed. The results of this study show that a positive energy balance permits R. philippinarum gonadal development and accumulation of reserves both in low and high temperature conditions. In low temperature situations, gonadal development is slower and the energy reserves are accumulated in the form of carbohydrates. When the clams are conditioned at high temperatures, gonadal development is fast and complete, carbohydrates are consumed and lipids are accumulated.

Effects of Indoor Horseback Riding and Virtual Reality Exercises on the Dynamic Balance Ability of Normal Healthy Adults

PubMed Central

Lee, Daehee; Lee, Sangyong; Park, Jungseo

2014-01-01

[Purpose] The objective of this study was to determine the effect of indoor horseback riding and virtual reality exercises on the dynamic balance ability of normal adults. [Subjects] This study enrolled 24 normal adults and divided them into two groups: an indoor horseback riding exercise group (IHREG, n = 12) and a virtual reality exercise group (VREG, n = 12). [Methods] IHREG exercised on indoor horseback riding equipment and VREG exercised using the Nintendo Wii Fit three times a week for six weeks. The Biodex Balance System was used to analyze dynamic balance as measured by the overall stability index (OSI), anteroposterior stability index (APSI), and mediolateral stability index (MLSI). [Results] In the within-group comparison, IHREG and VERG both showed significant decreases in the dynamic balance indexes of OSI, APSI, and MLSI after the intervention, but no significant difference was found between the groups. [Conclusion] Both indoor horseback riding and virtual reality exercises were effective at improving the subjects’ dynamic balance ability as measured by OSI, APSI, and MLSI, and can be used as additional exercises for patients with conditions affecting postural control. PMID:25540494

MSEE: Stochastic Cognitive Linguistic Behavior Models for Semantic Sensing

DTIC Science & Technology

2013-09-01

recognition, a Gaussian Process Dynamic Model with Social Network Analysis (GPDM-SNA) for a small human group action recognition, an extended GPDM-SNA...44  3.2. Small Human Group Activity Modeling Based on Gaussian Process Dynamic Model and Social Network Analysis (SN-GPDM...51  Approved for public release; distribution unlimited. 3 3.2.3. Gaussian Process Dynamical Model and

A Computerized Asthma Outcomes Measure Is Feasible for Disease Management

PubMed Central

Turner-Bowker, Diane M.; Saris-Baglama, Renee N.; Anatchkova, Milena; Mosen, David M.

2010-01-01

Objective To develop and test an online assessment referred to as the ASTHMA-CAT (computerized adaptive testing), a patient-based asthma impact, control, and generic health-related quality of life (HRQOL) measure. Study Design Cross-sectional pilot study of the ASTHMA-CAT’s administrative feasibility in a disease management population. Methods The ASTHMA-CAT included a dynamic or static Asthma Impact Survey (AIS), Asthma Control Test, and SF-8 Health Survey. A sample of clinician-diagnosed adult asthmatic patients (N = 114) completed the ASTHMA-CAT. Results were used to evaluate administrative feasibility of the instrument and psychometric performance of the dynamic AIS relative to the static AIS. A prototype aggregate (group-level) report was developed and reviewed by care providers. Results Online administration of the ASTHMA-CAT was feasible for patients in disease management. The dynamic AIS functioned well compared with the static AIS in preliminary studies evaluating response burden, precision, and validity. Providers found reports to be relevant, useful, and applicable for care management. Conclusion The ASTHMA-CAT may facilitate asthma care management. PMID:20852675

A consistent S-Adenosylmethionine force field improved by dynamic Hirshfeld-I atomic charges for biomolecular simulation

NASA Astrophysics Data System (ADS)

Saez, David Adrian; Vöhringer-Martinez, Esteban

2015-10-01

S-Adenosylmethionine (AdoMet) is involved in many biological processes as cofactor in enzymes transferring its sulfonium methyl group to various substrates. Additionally, it is used as drug and nutritional supplement to reduce the pain in osteoarthritis and against depression. Due to the biological relevance of AdoMet it has been part of various computational simulation studies and will also be in the future. However, to our knowledge no rigorous force field parameter development for its simulation in biological systems has been reported. Here, we use electronic structure calculations combined with molecular dynamics simulations in explicit solvent to develop force field parameters compatible with the AMBER99 force field. Additionally, we propose new dynamic Hirshfeld-I atomic charges which are derived from the polarized electron density of AdoMet in aqueous solution to describe its electrostatic interactions in biological systems. The validation of the force field parameters and the atomic charges is performed against experimental interproton NOE distances of AdoMet in aqueous solution and crystal structures of AdoMet in the cavity of three representative proteins.

Lava Flow Dynamics

NASA Technical Reports Server (NTRS)

Taylor, G. Jeffrey

1996-01-01

This grant originally had four major tasks, all of which were addressed to varying extents during the course of the research: (1) Measure the fractal dimensions of lava flows as a function of topography, substrate, and rheology; (2) The nature of lava tube systems and their relation to flow fields; (3) A quantitative assessment of lava flow dynamics in light of the fractal nature of lava flow margins; and (4) Development and application of a new remote sensing tool based on fractal properties. During the course of the research, the project expanded to include the following projects: (1) A comparison of what we can-learn from remote sensing studies of lava flow morphology and from studies of samples of lava flows; (2) Study of a terrestrial analog of the nakhlites, one of the groups of meteorites from Mars; and (3) Study of the textures of Hawaiian basalts as an aid in understanding the dynamics (flow rates, inflation rates, thermal history) of flow interiors. In addition, during the first year an educational task (development and writing of a teacher's guide and activity set to accompany the lunar sample disk when it is sent to schools) was included.

Approach for describing spatial dynamics of quantum light-matter interaction in dispersive dissipative media

NASA Astrophysics Data System (ADS)

Zyablovsky, A. A.; Andrianov, E. S.; Nechepurenko, I. A.; Dorofeenko, A. V.; Pukhov, A. A.; Vinogradov, A. P.

2017-05-01

Solving the challenging problem of the amplification and generation of an electromagnetic field in nanostructures enables us to implement many properties of the electromagnetic field at the nanoscale in practical applications. A first-principles quantum-mechanical consideration of such a problem is sufficiently restricted by the exponentially large number of degrees of freedom and does not allow the electromagnetic-field dynamics to be described if it involves a high number of interacting atoms and modes of the electromagnetic field. Conversely, the classical description of electromagnetic fields is incorrect at the nanoscale due to the high level of quantum fluctuations connected to high dissipation and noise levels. In this paper, we develop a framework with a significantly reduced number of degrees of freedom, which describes the quantum spatial dynamics of electromagnetic fields interacting with atoms. As an example, we consider the interaction between atoms placed in a metallic subwavelength groove and demonstrate that a spontaneously excited electromagnetic pulse propagates with the group velocity. The developed approach may be exploited to describe nonuniform amplification and propagation of electromagnetic fields in arbitrary dispersive dissipative systems.

Dynamics of Conceptual Change in Small Group Science Interactions.

ERIC Educational Resources Information Center

Fellows, Nancy J.

This paper documents the dynamics of the social interactions within two small groups of sixth grade students as they solved problems and attempted to understand the concepts related to the nature of matter and molecular theory. Similarities and differences of social interactions between the two groups are compared, and interpretations presented…

Teaching Group Dynamics through an Application-Based Learning Approach

ERIC Educational Resources Information Center

Harper, Melinda S.; Allegretti, Christine L.

2015-01-01

The purpose of this study was to demonstrate how a structured experiential course can be used to teach students to lead group discussions. Group dynamics and leadership skills were taught through two teaching strategies in the course: the first method required junior- and senior-level undergraduate students to participate in a process-oriented…

The Dynamics of Access to Groups in Working Memory

ERIC Educational Resources Information Center

Farrell, Simon; Lelievre, Anna

2012-01-01

The finding that participants leave a pause between groups when attempting serial recall of temporally grouped lists has been taken to indicate access to a hierarchical representation of the list in working memory. An alternative explanation is that the dynamics of serial recall solely reflect output (rather than memorial) processes, with the…

Effect of Cognitive Demand on Functional Visual Field Performance in Senior Drivers with Glaucoma

PubMed Central

Gangeddula, Viswa; Ranchet, Maud; Akinwuntan, Abiodun E.; Bollinger, Kathryn; Devos, Hannes

2017-01-01

Purpose: To investigate the effect of cognitive demand on functional visual field performance in drivers with glaucoma. Method: This study included 20 drivers with open-angle glaucoma and 13 age- and sex-matched controls. Visual field performance was evaluated under different degrees of cognitive demand: a static visual field condition (C1), dynamic visual field condition (C2), and dynamic visual field condition with active driving (C3) using an interactive, desktop driving simulator. The number of correct responses (accuracy) and response times on the visual field task were compared between groups and between conditions using Kruskal–Wallis tests. General linear models were employed to compare cognitive workload, recorded in real-time through pupillometry, between groups and conditions. Results: Adding cognitive demand (C2 and C3) to the static visual field test (C1) adversely affected accuracy and response times, in both groups (p < 0.05). However, drivers with glaucoma performed worse than did control drivers when the static condition changed to a dynamic condition [C2 vs. C1 accuracy; glaucoma: median difference (Q1–Q3) 3 (2–6.50) vs. controls: 2 (0.50–2.50); p = 0.05] and to a dynamic condition with active driving [C3 vs. C1 accuracy; glaucoma: 2 (2–6) vs. controls: 1 (0.50–2); p = 0.02]. Overall, drivers with glaucoma exhibited greater cognitive workload than controls (p = 0.02). Conclusion: Cognitive demand disproportionately affects functional visual field performance in drivers with glaucoma. Our results may inform the development of a performance-based visual field test for drivers with glaucoma. PMID:28912712

Relationship between antigravity control and postural control in young children.

PubMed

Sellers, J S

1988-04-01

The purposes of this study were 1) to determine the relationship between antigravity control (supine flexion and prone extension) and postural control (static and dynamic balance), 2) to determine the quality of antigravity and postural control, and 3) to determine whether sex and ethnic group differences correlate with differences in antigravity control and postural control in young children. I tested 107 black, Hispanic, and Caucasian children in a Head Start program, with a mean age of 61 months. The study results showed significant relationships between antigravity control and postural control. Subjects' supine flexion performance was significantly related to the quantity and quality of their static and dynamic balance performance, whereas prone extension performance was related only to the quality of dynamic balance performance. Quality scale measurements (r = .90) indicated that the children in this study had not yet developed full antigravity or postural control. The study results revealed differences between sexes in the quality of static balance and prone extension performance and ethnic differences in static balance, dynamic balance, and prone extension performance.

Finite-temperature dynamics of the Mott insulating Hubbard chain

NASA Astrophysics Data System (ADS)

Nocera, Alberto; Essler, Fabian H. L.; Feiguin, Adrian E.

2018-01-01

We study the dynamical response of the half-filled one-dimensional Hubbard model for a range of interaction strengths U and temperatures T by a combination of numerical and analytical techniques. Using time-dependent density matrix renormalization group computations we find that the single-particle spectral function undergoes a crossover to a spin-incoherent Luttinger liquid regime at temperatures T ˜J =4 t2/U for sufficiently large U >4 t . At smaller values of U and elevated temperatures the spectral function is found to exhibit two thermally broadened bands of excitations, reminiscent of what is found in the Hubbard-I approximation. The dynamical density-density response function is shown to exhibit a finite-temperature resonance at low frequencies inside the Mott gap, with a physical origin similar to the Villain mode in gapped quantum spin chains. We complement our numerical computations by developing an analytic strong-coupling approach to the low-temperature dynamics in the spin-incoherent regime.

EVOLUTION OF GALAXY GROUPS IN THE ILLUSTRIS SIMULATION

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

Raouf, Mojtaba; Khosroshahi, Habib G.; Dariush, A., E-mail: m.raouf@ipm.ir

We present the first study of the evolution of galaxy groups in the Illustris simulation. We focus on dynamically relaxed and unrelaxed galaxy groups representing dynamically evolved and evolving galaxy systems, respectively. The evolutionary state of a group is probed from its luminosity gap and separation between the brightest group galaxy and the center of mass of the group members. We find that the Illustris simulation overproduces galaxy systems with a large luminosity gap, known as fossil systems, in comparison to observations and the probed semi-analytical predictions. However, this simulation is just as successful as the probed semi-analytic model inmore » recovering the correlation between luminosity gap and offset of the luminosity centroid. We find evolutionary tracks based on luminosity gap that indicate that a group with a large luminosity gap is rooted in one with a small luminosity gap, regardless of the position of the brightest group galaxy within the halo. This simulation helps to explore, for the first time, the black hole mass and its accretion rate in galaxy groups. For a given stellar mass of the brightest group galaxies, the black hole mass is larger in dynamically relaxed groups with a lower rate of mass accretion. We find this to be consistent with the latest observational studies of radio activity in the brightest group galaxies in fossil groups. We also find that the intragalactic medium in dynamically evolved groups is hotter for a given halo mass than that in evolving groups, again consistent with earlier observational studies.« less

Dynamics of zebra finch and mockingbird vocalizations

NASA Astrophysics Data System (ADS)

Cimenser, Aylin

Along with humans, whales, and bats, three groups of birds which include songbirds (oscines) such as the Zebra Finch (Taeniopygia guttata) and Mockingbird (Mimus polyglottos) are the only creatures known to learn sounds by imitation. Numerous similarities between human and songbird vocalizations exist and, recently, it has been shown that Zebra Finch in particular possesses a gene, FoxP2, known to be involved in human language. This thesis investigates song development in Zebra Finches, as well as the temporal dynamics of song in Mockingbirds. Zebra Finches have long been the system of choice for studying vocal development, ontogeny, and complexity in birdsong. Physicists find them intriguing because the spectrally complex vocalizations of the Zebra Finch can exhibit sudden transitions to chaotic dynamics, period doubling & mode-locking phenomena. Mockingbirds, by contrast, provide an ideal system to examine the richness of an avian repertoire, since these musically versatile songbirds typically know upwards of 200 songs. To analyse birdsong data, we have developed a novel clustering algorithm that can be applied to the bird's syllables, tracing their dynamics back to the earliest stages of vocal development. To characterize birdsong we have used Fourier techniques, based upon multitaper spectral analysis, to optimally work around the constraints imposed by (Heisenberg's) time-frequency uncertainty principle. Furthermore, estimates that provide optimal compromise between frequency and temporal resolution have beautiful connections with solutions to the Helmholtz wave equation in prolate spheroidal coordinates. We have used this connection to provide firm foundation for certain heuristics used in the literature to compute associated spectral derivatives and supply a pedagogical account here in this thesis. They are of interest because spectral derivatives emphasize sudden changes in the dynamics of the underlying phenomenon, and often provide a nice way to visualize such dynamics. Our Zebra Finch data consist of continuous recordings of six tutored birds from the early, plastic stages of sound production to the development of fully crystallized mature song. Our analysis reveals that well before the Zebra Finch hears adult song, identifiably distinct clusters are observable for all birds in the same regions of feature space. (Abstract shortened by UMI.)

Solution to the SLAM problem in low dynamic environments using a pose graph and an RGB-D sensor.

PubMed

Lee, Donghwa; Myung, Hyun

2014-07-11

In this study, we propose a solution to the simultaneous localization and mapping (SLAM) problem in low dynamic environments by using a pose graph and an RGB-D (red-green-blue depth) sensor. The low dynamic environments refer to situations in which the positions of objects change over long intervals. Therefore, in the low dynamic environments, robots have difficulty recognizing the repositioning of objects unlike in highly dynamic environments in which relatively fast-moving objects can be detected using a variety of moving object detection algorithms. The changes in the environments then cause groups of false loop closing when the same moved objects are observed for a while, which means that conventional SLAM algorithms produce incorrect results. To address this problem, we propose a novel SLAM method that handles low dynamic environments. The proposed method uses a pose graph structure and an RGB-D sensor. First, to prune the falsely grouped constraints efficiently, nodes of the graph, that represent robot poses, are grouped according to the grouping rules with noise covariances. Next, false constraints of the pose graph are pruned according to an error metric based on the grouped nodes. The pose graph structure is reoptimized after eliminating the false information, and the corrected localization and mapping results are obtained. The performance of the method was validated in real experiments using a mobile robot system.