Environmental and spatial drivers of taxonomic, functional, and phylogenetic characteristics of bat communities in human-modified landscapes.

PubMed

Cisneros, Laura M; Fagan, Matthew E; Willig, Michael R

2016-01-01

Assembly of species into communities following human disturbance (e.g., deforestation, fragmentation) may be governed by spatial (e.g., dispersal) or environmental (e.g., niche partitioning) mechanisms. Variation partitioning has been used to broadly disentangle spatial and environmental mechanisms, and approaches utilizing functional and phylogenetic characteristics of communities have been implemented to determine the relative importance of particular environmental (or niche-based) mechanisms. Nonetheless, few studies have integrated these quantitative approaches to comprehensively assess the relative importance of particular structuring processes. We employed a novel variation partitioning approach to evaluate the relative importance of particular spatial and environmental drivers of taxonomic, functional, and phylogenetic aspects of bat communities in a human-modified landscape in Costa Rica. Specifically, we estimated the amount of variation in species composition (taxonomic structure) and in two aspects of functional and phylogenetic structure (i.e., composition and dispersion) along a forest loss and fragmentation gradient that are uniquely explained by landscape characteristics (i.e., environment) or space to assess the importance of competing mechanisms. The unique effects of space on taxonomic, functional and phylogenetic structure were consistently small. In contrast, landscape characteristics (i.e., environment) played an appreciable role in structuring bat communities. Spatially-structured landscape characteristics explained 84% of the variation in functional or phylogenetic dispersion, and the unique effects of landscape characteristics significantly explained 14% of the variation in species composition. Furthermore, variation in bat community structure was primarily due to differences in dispersion of species within functional or phylogenetic space along the gradient, rather than due to differences in functional or phylogenetic composition. Variation among bat communities was related to environmental mechanisms, especially niche-based (i.e., environmental) processes, rather than spatial mechanisms. High variation in functional or phylogenetic dispersion, as opposed to functional or phylogenetic composition, suggests that loss or gain of niche space is driving the progressive loss or gain of species with particular traits from communities along the human-modified gradient. Thus, environmental characteristics associated with landscape structure influence functional or phylogenetic aspects of bat communities by effectively altering the ways in which species partition niche space.

Environmental and spatial drivers of taxonomic, functional, and phylogenetic characteristics of bat communities in human-modified landscapes

PubMed Central

Fagan, Matthew E.; Willig, Michael R.

2016-01-01

Background Assembly of species into communities following human disturbance (e.g., deforestation, fragmentation) may be governed by spatial (e.g., dispersal) or environmental (e.g., niche partitioning) mechanisms. Variation partitioning has been used to broadly disentangle spatial and environmental mechanisms, and approaches utilizing functional and phylogenetic characteristics of communities have been implemented to determine the relative importance of particular environmental (or niche-based) mechanisms. Nonetheless, few studies have integrated these quantitative approaches to comprehensively assess the relative importance of particular structuring processes. Methods We employed a novel variation partitioning approach to evaluate the relative importance of particular spatial and environmental drivers of taxonomic, functional, and phylogenetic aspects of bat communities in a human-modified landscape in Costa Rica. Specifically, we estimated the amount of variation in species composition (taxonomic structure) and in two aspects of functional and phylogenetic structure (i.e., composition and dispersion) along a forest loss and fragmentation gradient that are uniquely explained by landscape characteristics (i.e., environment) or space to assess the importance of competing mechanisms. Results The unique effects of space on taxonomic, functional and phylogenetic structure were consistently small. In contrast, landscape characteristics (i.e., environment) played an appreciable role in structuring bat communities. Spatially-structured landscape characteristics explained 84% of the variation in functional or phylogenetic dispersion, and the unique effects of landscape characteristics significantly explained 14% of the variation in species composition. Furthermore, variation in bat community structure was primarily due to differences in dispersion of species within functional or phylogenetic space along the gradient, rather than due to differences in functional or phylogenetic composition. Discussion Variation among bat communities was related to environmental mechanisms, especially niche-based (i.e., environmental) processes, rather than spatial mechanisms. High variation in functional or phylogenetic dispersion, as opposed to functional or phylogenetic composition, suggests that loss or gain of niche space is driving the progressive loss or gain of species with particular traits from communities along the human-modified gradient. Thus, environmental characteristics associated with landscape structure influence functional or phylogenetic aspects of bat communities by effectively altering the ways in which species partition niche space. PMID:27761338

The Effect of Structured Divergent Prompts on Knowledge Construction

ERIC Educational Resources Information Center

Howell, Ginger S.; Akpanudo, Usenime; Chen, Mengyi; Sutherlin, Autumn L.; James, Laura E.

2014-01-01

Discussion forums are a widely used activity in online courses. However, knowledge construction within online discussion rarely reaches higher levels. Therefore, it is important to understand which aspects of online discussion encourage learning and increase knowledge construction. This paper investigates the effect three Structured Divergent…

Student perceptions: Importance of and satisfaction with aspects of an online biology course

NASA Astrophysics Data System (ADS)

Hendry, Sheila R.

Research of student satisfaction with various facets of an online biology course, as well as the perceived importance of these aspects, was conducted during the summer and fall 2004 semesters within a course, History of Biology, at a university in the southeastern United States. This research is based on the theory of transactional distance, which involves dialogue between the teacher and student, the physical environments of both the student and teacher, and the emotional environments of each. Student ratings of importance and satisfaction regarding aspects of convenience, grade earned/knowledge learned, emotional health, communication, and student support were collected toward the end of each semester, via the online course, using the researcher-designed Student Perceptions Survey. Statistics with repeated measures ANOVA, using an alpha of 0.05, determined differences between importance and satisfaction ratings for each of these aspects. Students perceived grade earned/knowledge learned to be the most important aspect of learning online, although it is not an aspect unique to online courses. All of the aspects included in the study were found to be at least somewhat important. Convenience was the aspect with which students were most satisfied, with students at least somewhat satisfied with the other aspects. Although convenience is an inherent strength of the online course format, instructors should be aware of how important it is to design requirements of the online class to help students acquire knowledge while allowing them to do so at their own pace. Well-structured content, prompt feedback, encouragement of quality student-instructor communication, and student support are all parts of a positive online course experience. The Student Perceptions Survey, created specifically for this research, can have substantial value both in the creation of new online courses and in the evaluation of pre-existing courses. It can provide important information that can be used in developing or modifying an online course, to determine whether revisions have been effective, or to assess changes in student perceptions. In addition, as changes in technology occur, the survey can be further revised, with maintenance of core items, so that it will remain an effective evaluation tool for online courses.

Probabilistic structural analysis methods for space propulsion system components

NASA Technical Reports Server (NTRS)

Chamis, C. C.

1986-01-01

The development of a three-dimensional inelastic analysis methodology for the Space Shuttle main engine (SSME) structural components is described. The methodology is composed of: (1) composite load spectra, (2) probabilistic structural analysis methods, (3) the probabilistic finite element theory, and (4) probabilistic structural analysis. The methodology has led to significant technical progress in several important aspects of probabilistic structural analysis. The program and accomplishments to date are summarized.

Delivery of Functionality in Complex Food Systems: Physically Inspired Approaches from Nanoscale to Microscale, Wageningen 18–21 October 2009

PubMed Central

Ubbink, Job; Duchateau, Guus

2010-01-01

The Wageningen Delivery of Functionality symposium covered all aspects involved with food structural design to arrive at high-quality foods which meet demanding customer expectations and regulatory requirements. The symposium integrated aspects from the structural organization of foods at molecular and supramolecular scales to dedicated techniques required to describe and visualize such structures, the gastro-intestinal events and how to model these in a laboratory setting, and finally the impact those food structures and ingredients have on the consumer’s physiology and on the human perception. As an interdisciplinary platform, bringing together more than 160 researchers from academia and industry, the symposium meanwhile fulfills an important role in the food science community. PMID:21125000

Beatles versus Beethoven: Using Music to Introduce Cognitive Structures

ERIC Educational Resources Information Center

Herman, Andrew P.; Wyant, Christopher P.

2006-01-01

The concepts of social cognition and cognitive structures are important aspects of constructivism and human communication theory. By asking students to listen to different musical selections and fill in a simple rubric, different schemas become apparent. This creates an opportunity to discuss how cognitions relate to communication. Students who…

Much Ado about Nothing--Or at Best, Very Little

ERIC Educational Resources Information Center

Widaman, Keith F.

2014-01-01

Latent variable structural equation modeling has become the analytic method of choice in many domains of research in psychology and allied social sciences. One important aspect of a latent variable model concerns the relations hypothesized to hold between latent variables and their indicators. The most common specification of structural equation…

Alternative Multiple Imputation Inference for Mean and Covariance Structure Modeling

ERIC Educational Resources Information Center

Lee, Taehun; Cai, Li

2012-01-01

Model-based multiple imputation has become an indispensable method in the educational and behavioral sciences. Mean and covariance structure models are often fitted to multiply imputed data sets. However, the presence of multiple random imputations complicates model fit testing, which is an important aspect of mean and covariance structure…

A review on non-linear aeroelasticity of high aspect-ratio wings

NASA Astrophysics Data System (ADS)

Afonso, Frederico; Vale, José; Oliveira, Éder; Lau, Fernando; Suleman, Afzal

2017-02-01

Current economic constraints and environmental regulations call for design of more efficient aircraft configurations. An observed trend in aircraft design to reduce the lift induced drag and improve fuel consumption and emissions is to increase the wing aspect-ratio. However, a slender wing is more flexible and subject to higher deflections under the same operating conditions. This effect may lead to changes in dynamic behaviour and in aeroelastic response, potentially resulting in instabilities. Therefore, it is important to take into account geometric non-linearities in the design of high aspect-ratio wings, as well as having accurate computational codes that couple the aerodynamic and structural models in the presence of non-linearities. Here, a review on the state-of-the-art on non-linear aeroelasticity of high aspect-ratio wings is presented. The methodologies employed to analyse high aspect-ratio wings are presented and their applications discussed. Important observations from the state-of-the-art studies are drawn and the current challenges in the field are identified.

System identification of the JPL micro-precision interferometer truss - Test-analysis reconciliation

NASA Technical Reports Server (NTRS)

Red-Horse, J. R.; Marek, E. L.; Levine-West, M.

1993-01-01

The JPL Micro-Precision Interferometer (MPI) is a testbed for studying the use of control-structure interaction technology in the design of space-based interferometers. A layered control architecture will be employed to regulate the interferometer optical system to tolerances in the nanometer range. An important aspect of designing and implementing the control schemes for such a system is the need for high fidelity, test-verified analytical structural models. This paper focuses on one aspect of the effort to produce such a model for the MPI structure, test-analysis model reconciliation. Pretest analysis, modal testing, and model refinement results are summarized for a series of tests at both the component and full system levels.

Pore-Scale Modeling of Pore Structure Effects on P-Wave Scattering Attenuation in Dry Rocks

PubMed Central

Li, Tianyang; Qiu, Hao; Wang, Feifei

2015-01-01

Underground rocks usually have complex pore system with a variety of pore types and a wide range of pore size. The effects of pore structure on elastic wave attenuation cannot be neglected. We investigated the pore structure effects on P-wave scattering attenuation in dry rocks by pore-scale modeling based on the wave theory and the similarity principle. Our modeling results indicate that pore size, pore shape (such as aspect ratio), and pore density are important factors influencing P-wave scattering attenuation in porous rocks, and can explain the variation of scattering attenuation at the same porosity. From the perspective of scattering attenuation, porous rocks can safely suit to the long wavelength assumption when the ratio of wavelength to pore size is larger than 15. Under the long wavelength condition, the scattering attenuation coefficient increases as a power function as the pore density increases, and it increases exponentially with the increase in aspect ratio. For a certain porosity, rocks with smaller aspect ratio and/or larger pore size have stronger scattering attenuation. When the pore aspect ratio is larger than 0.5, the variation of scattering attenuation at the same porosity is dominantly caused by pore size and almost independent of the pore aspect ratio. These results lay a foundation for pore structure inversion from elastic wave responses in porous rocks. PMID:25961729

From laptop to benchtop to bedside: Structure-based Drug Design on Protein Targets

PubMed Central

Chen, Lu; Morrow, John K.; Tran, Hoang T.; Phatak, Sharangdhar S.; Du-Cuny, Lei; Zhang, Shuxing

2013-01-01

As an important aspect of computer-aided drug design, structure-based drug design brought a new horizon to pharmaceutical development. This in silico method permeates all aspects of drug discovery today, including lead identification, lead optimization, ADMET prediction and drug repurposing. Structure-based drug design has resulted in fruitful successes drug discovery targeting protein-ligand and protein-protein interactions. Meanwhile, challenges, noted by low accuracy and combinatoric issues, may also cause failures. In this review, state-of-the-art techniques for protein modeling (e.g. structure prediction, modeling protein flexibility, etc.), hit identification/optimization (e.g. molecular docking, focused library design, fragment-based design, molecular dynamic, etc.), and polypharmacology design will be discussed. We will explore how structure-based techniques can facilitate the drug discovery process and interplay with other experimental approaches. PMID:22316152

The importance of the specific Z-DNA structure and polyamines in carcinogenesis: fact or fiction.

PubMed

Juranic, Z; Kidric, M; Tomin, R; Juranić, I; Spuzić, I; Petrović, J

1991-08-01

In this work some aspects of carcinogenesis are given. The importance of the emergence of Z or H DNA structure in the gene, or in the flanking gene sequences for the gene deletion and unusual gene recombination, is discussed. Some considerations on the role of selective pressure (of polyamines, of Mg2+, of the various levels of topoisomerase II, and of ATP) in the process of oncogene amplification, are given too.

Lexical Exploration for Advanced ESL Students in Public Health.

ERIC Educational Resources Information Center

Wakai, Helen K.

This paper develops guidelines for instructional materials for advanced English as a second language students in which the objects of instruction would be: (1) the relationship between surface structures of lexical items and their underlying meanings; (2) the important aspects of structural forms; and (3) the special uses of words in the lexicon…

The Big Picture

ERIC Educational Resources Information Center

Coleman, William F.

2004-01-01

The importance of chemistry in daily life of the students is discussed. The approach provides a connection between the details of molecular structure, bonding and reactivity with many aspects of the impact of chemistry on the society.

Physician Rating Websites: What Aspects Are Important to Identify a Good Doctor, and Are Patients Capable of Assessing Them? A Mixed-Methods Approach Including Physicians’ and Health Care Consumers’ Perspectives

PubMed Central

Schulz, Peter J

2017-01-01

Background Physician rating websites (PRWs) offer health care consumers the opportunity to evaluate their doctor anonymously. However, physicians’ professional training and experience create a vast knowledge gap in medical matters between physicians and patients. This raises ethical concerns about the relevance and significance of health care consumers’ evaluation of physicians’ performance. Objective To identify the aspects physician rating websites should offer for evaluation, this study investigated the aspects of physicians and their practice relevant for identifying a good doctor, and whether health care consumers are capable of evaluating these aspects. Methods In a first step, a Delphi study with physicians from 4 specializations was conducted, testing various indicators to identify a good physician. These indicators were theoretically derived from Donabedian, who classifies quality in health care into pillars of structure, process, and outcome. In a second step, a cross-sectional survey with health care consumers in Switzerland (N=211) was launched based on the indicators developed in the Delphi study. Participants were asked to rate the importance of these indicators to identify a good physician and whether they would feel capable to evaluate those aspects after the first visit to a physician. All indicators were ordered into a 4×4 grid based on evaluation and importance, as judged by the physicians and health care consumers. Agreement between the physicians and health care consumers was calculated applying Holsti’s method. Results In the majority of aspects, physicians and health care consumers agreed on what facets of care were important and not important to identify a good physician and whether patients were able to evaluate them, yielding a level of agreement of 74.3%. The two parties agreed that the infrastructure, staff, organization, and interpersonal skills are both important for a good physician and can be evaluated by health care consumers. Technical skills of a doctor and outcomes of care were also judged to be very important, but both parties agreed that they would not be evaluable by health care consumers. Conclusions Health care consumers in Switzerland show a high appraisal of the importance of physician-approved criteria for assessing health care performance and a moderate self-perception of how capable they are of assessing the quality and performance of a physician. This study supports that health care consumers are differentiating between aspects they perceive they would be able to evaluate after a visit to a physician (such as attributes of structure and the interpersonal skills of a doctor), and others that lay beyond their ability to make an accurate judgment about (such as technical skills of a physician and outcome of care). PMID:28461285

Chitin Research Revisited

PubMed Central

Khoushab, Feisal; Yamabhai, Montarop

2010-01-01

Two centuries after the discovery of chitin, it is widely accepted that this biopolymer is an important biomaterial in many aspects. Numerous studies on chitin have focused on its biomedical applications. In this review, various aspects of chitin research including sources, structure, biosynthesis, chitinolytic enzyme, chitin binding protein, genetic engineering approach to produce chitin, chitin and evolution, and a wide range of applications in bio- and nanotechnology will be dealt with. PMID:20714419

Subjective Control and Health Among Mexican-Origin Elders in Mexico and the United States: Structural Considerations in Comparative Research

PubMed Central

Hill, Terrence D.

2009-01-01

Objectives This study examines the joint impact of psychological and structural factors on Mexican and Mexican American elders' sense of personal control over important aspects of their lives and health in Mexico and the United States. Methods We employ the Mexican Health and Aging Study (MHAS) and the Hispanic Established Populations for Epidemiologic Studies of the Elderly (H-EPESE) to explore patterns of association among structural factors, personal characteristics, indicators of material and physical vulnerability, and expressed locus of control. Results The results suggest that an older individual's sense of personal control over important aspects of his or her life, including health, reflects real material and social resources in addition to individual predispositions. In Mexico, only the most privileged segment of the population has health insurance, and coverage increases one's sense of personal control. In the United States, on the other hand, Medicare guarantees basic coverage to the vast majority of Mexican Americans over 65, reducing its impact on one's sense of control. Discussion Psychological characteristics affect older individuals' sense of personal control over aspects of their health, but the effects are mediated by the economic and health services context in which they are expressed. PMID:19332436

Aspects of perceptual development and rehabilitation.

PubMed

Kanevsky, D; Yabrov, A

1988-09-01

It is hypothesized that two anatomically distinct structures--sensory and cognitive--are jointly responsible for perception. In normal individuals the sensory structure is developed at birth, whereas the cognitive one develops after birth under the influence of information received through the sensory structure. Only information that is consciously perceived and comprehended is essential for development of cognitive structure. Consequently, creation of an optimal substream of this cognizable information is an important objective for the therapist or teacher.

Nanoparticle agglomeration in an evaporating levitated droplet for different acoustic amplitudes

NASA Astrophysics Data System (ADS)

Tijerino, Erick; Basu, Saptarshi; Kumar, Ranganathan

2013-01-01

Radiatively heated levitated functional droplets with nanosilica suspensions exhibit three distinct stages namely pure evaporation, agglomeration, and finally structure formation. The temporal history of the droplet surface temperature shows two inflection points. One inflection point corresponds to a local maximum and demarcates the end of transient heating of the droplet and domination of vaporization. The second inflection point is a local minimum and indicates slowing down of the evaporation rate due to surface accumulation of nanoparticles. Morphology and final precipitation structures of levitated droplets are due to competing mechanisms of particle agglomeration, evaporation, and shape deformation. In this work, we provide a detailed analysis for each process and propose two important timescales for evaporation and agglomeration that determine the final diameter of the structure formed. It is seen that both agglomeration and evaporation timescales are similar functions of acoustic amplitude (sound pressure level), droplet size, viscosity, and density. However, we show that while the agglomeration timescale decreases with initial particle concentration, the evaporation timescale shows the opposite trend. The final normalized diameter can be shown to be dependent solely on the ratio of agglomeration to evaporation timescales for all concentrations and acoustic amplitudes. The structures also exhibit various aspect ratios (bowls, rings, spheroids) which depend on the ratio of the deformation timescale (tdef) and the agglomeration timescale (tg). For tdef

Simulation Games and Political Attitudes: The Importance of Role Identification and Game Structure.

ERIC Educational Resources Information Center

Livingston, Samuel A.

In an experiment conducted under classroom conditions with 8th grade students, the simulation game "Democracy" was shown to be effective at teaching that "log-rolling" is an acceptable part of the legislative process. Two aspects of the game--role identification and game structure--were shown to contribute independently to its effectiveness.…

Youth Policies in the European Union. Structures and Training. Studies No. 7.

ERIC Educational Resources Information Center

Lazos, C. G.

This volume contains three studies that address important and complementary aspects of youth work as it is developing in the Member States of the European Union. Chapter 1, Youth Structures and Policies at National Level, has two parts. The first describes the specific nature of youth policies carried out by the various governments and the…

Experimental correlation of melt structures, nucleation rates, and thermal histories of silicate melts

NASA Technical Reports Server (NTRS)

Boynton, W. V.; DRAKE; HILDEBRAND; JONES; LEWIS; TREIMAN; WARK

1987-01-01

The theory and measurement of the structure of liquids is an important aspect of modern metallurgy and igneous petrology. Liquid structure exerts strong controls on both the types of crystals that may precipitate from melts and on the chemical composition of those crystals. An interesting aspect of melt structure studies is the problem of melt memories; that is, a melt can retain a memory of previous thermal history. This memory can influence both nucleation behavior and crystal composition. This melt memory may be characterized quantitatively with techniques such as Raman, infrared and NMR spectroscopy to provide information on short-range structure. Melt structure studies at high temperature will take advantage of the microgravity conditions of the Space Station to perform containerless experiments. Melt structure determinations at high temperature (experiments that are greatly facilitated by containerless technology) will provide invaluable information for materials science, glass technology, and geochemistry. In conjunction with studies of nucleation behavior and nucleation rates, information relevant to nucleation in magma chambers in terrestrial planets will be acquired.

Local topography shapes fine-scale spatial genetic structure in the Arkansas Valley evening primrose, Oenothera harringtonii (Onagraceae).

PubMed

Rhodes, Matthew K; Fant, Jeremie B; Skogen, Krissa A

2014-01-01

Identifying factors that shape the spatial distribution of genetic variation is crucial to understanding many population- and landscape-level processes. In this study, we explore fine-scale spatial genetic structure in Oenothera harringtonii (Onagraceae), an insect-pollinated, gravity-dispersed herb endemic to the grasslands of south-central and southeastern Colorado, USA. We genotyped 315 individuals with 11 microsatellite markers and utilized a combination of spatial autocorrelation analyses and landscape genetic models to relate life history traits and landscape features to dispersal processes. Spatial genetic structure was consistent with theoretical expectations of isolation by distance, but this pattern was weak (Sp = 0.00374). Anisotropic analyses indicated that spatial genetic structure was markedly directional, in this case consistent with increased dispersal along prominent slopes. Landscape genetic models subsequently confirmed that spatial genetic variation was significantly influenced by local topographic heterogeneity, specifically that geographic distance, elevation and aspect were important predictors of spatial genetic structure. Among these variables, geographic distance was ~68% more important than elevation in describing spatial genetic variation, and elevation was ~42% more important than aspect after removing the effect of geographic distance. From these results, we infer a mechanism of hydrochorous seed dispersal along major drainages aided by seasonal monsoon rains. Our findings suggest that landscape features may shape microevolutionary processes at much finer spatial scales than typically considered, and stress the importance of considering how particular dispersal vectors are influenced by their environmental context. © The American Genetic Association 2014. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Aspirations of and Realities for Hong Kong Students: Is the "Formal" Transition System Effective?

ERIC Educational Resources Information Center

Pavlova, Margarita

2017-01-01

School to work transition is an important aspect of lifelong learning that has increased in significance as the knowledge-based economy takes off in developed countries. Rapid structural economic changes, the importance of innovation, and a shorter lifecycle of products require education systems to adjust to the needs of economies and individuals.…

Behavior Characteristics Desired in Faculty, by Deans at California Community Colleges: A Delphi Study

ERIC Educational Resources Information Center

Elliott, Alexandria

2016-01-01

Purpose: The community-college system in the United States has evolved tremendously since its beginning in 1901. There have been many changes, but one important aspect of the community college's structure that has continued to remain of utmost importance is the roles and responsibilities of faculty. The faculty has been traditionally hired based…

Development of methods for analysis of knee articular cartilage degeneration by magnetic resonance imaging data

NASA Astrophysics Data System (ADS)

Suponenkovs, Artjoms; Glazs, Aleksandrs; Platkajis, Ardis

2017-03-01

The aim of this paper is to describe the new methods for analyzing knee articular cartilage degeneration. The most important aspects regarding research about magnetic resonance imaging, knee joint anatomy, stages of knee osteoarthritis, medical image segmentation and relaxation times calculation. This paper proposes new methods for relaxation times calculation and medical image segmentation. The experimental part describes the most important aspect regarding analysing of articular cartilage relaxation times changing. This part contains experimental results, which show the codependence between relaxation times and organic structure. These experimental results and proposed methods can be helpful for early osteoarthritis diagnostics.

Balancing work, family and other lifestyle aspects: a qualitative study of Australian medical students' attitudes.

PubMed

Tolhurst, Helen M; Stewart, Stephen M

2004-10-04

To explore the attitudes of Australian medical students to the balance between work, family and other aspects of lifestyle, within a broader exploration of the issues that they regard as important to their decisions about future career. Qualitative study using semistructured focus groups and individual interviews. The three medical schools in New South Wales and a national conference for students interested in rural practice. First- and final-year medical students who volunteered for focus groups held between March and August 2002 (82 students in 10 groups) or for individual interviews held between July and December 2003 (48 students). Emergent themes relating to the balance of work, family and other aspects of lifestyle. Most students referred to a balance of work, family and lifestyle as an important factor in their career decisions. While indicating they were committed to medicine, they were unwilling to work to the exclusion of all else. Most saw family commitments as a high priority, and many saw "time out" as important in maintaining their health. Female students spoke of part-time work as essential for future happiness, while some male students expressed a preference for working part-time. They would seek to achieve balance by choosing to work in disciplines, locations and structures where limited-hours work is available, and would negotiate support from their partners and parents in caring for children. It is important that the medical profession continue to develop working and training structures that allow a balance of work, family and lifestyle.

Auditory psychophysics and perception.

PubMed

Hirsh, I J; Watson, C S

1996-01-01

In this review of auditory psychophysics and perception, we cite some important books, research monographs, and research summaries from the past decade. Within auditory psychophysics, we have singled out some topics of current importance: Cross-Spectral Processing, Timbre and Pitch, and Methodological Developments. Complex sounds and complex listening tasks have been the subject of new studies in auditory perception. We review especially work that concerns auditory pattern perception, with emphasis on temporal aspects of the patterns and on patterns that do not depend on the cognitive structures often involved in the perception of speech and music. Finally, we comment on some aspects of individual difference that are sufficiently important to question the goal of characterizing auditory properties of the typical, average, adult listener. Among the important factors that give rise to these individual differences are those involved in selective processing and attention.

Physician Rating Websites: What Aspects Are Important to Identify a Good Doctor, and Are Patients Capable of Assessing Them? A Mixed-Methods Approach Including Physicians' and Health Care Consumers' Perspectives.

PubMed

Rothenfluh, Fabia; Schulz, Peter J

2017-05-01

Physician rating websites (PRWs) offer health care consumers the opportunity to evaluate their doctor anonymously. However, physicians' professional training and experience create a vast knowledge gap in medical matters between physicians and patients. This raises ethical concerns about the relevance and significance of health care consumers' evaluation of physicians' performance. To identify the aspects physician rating websites should offer for evaluation, this study investigated the aspects of physicians and their practice relevant for identifying a good doctor, and whether health care consumers are capable of evaluating these aspects. In a first step, a Delphi study with physicians from 4 specializations was conducted, testing various indicators to identify a good physician. These indicators were theoretically derived from Donabedian, who classifies quality in health care into pillars of structure, process, and outcome. In a second step, a cross-sectional survey with health care consumers in Switzerland (N=211) was launched based on the indicators developed in the Delphi study. Participants were asked to rate the importance of these indicators to identify a good physician and whether they would feel capable to evaluate those aspects after the first visit to a physician. All indicators were ordered into a 4×4 grid based on evaluation and importance, as judged by the physicians and health care consumers. Agreement between the physicians and health care consumers was calculated applying Holsti's method. In the majority of aspects, physicians and health care consumers agreed on what facets of care were important and not important to identify a good physician and whether patients were able to evaluate them, yielding a level of agreement of 74.3%. The two parties agreed that the infrastructure, staff, organization, and interpersonal skills are both important for a good physician and can be evaluated by health care consumers. Technical skills of a doctor and outcomes of care were also judged to be very important, but both parties agreed that they would not be evaluable by health care consumers. Health care consumers in Switzerland show a high appraisal of the importance of physician-approved criteria for assessing health care performance and a moderate self-perception of how capable they are of assessing the quality and performance of a physician. This study supports that health care consumers are differentiating between aspects they perceive they would be able to evaluate after a visit to a physician (such as attributes of structure and the interpersonal skills of a doctor), and others that lay beyond their ability to make an accurate judgment about (such as technical skills of a physician and outcome of care). ©Fabia Rothenfluh, Peter J Schulz. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 01.05.2017.

Saying Good-by: An Example of Using a Good-by Technique and Concomitant Psychodrama in the Resolving of Family Grief.

ERIC Educational Resources Information Center

Kaminski, Robert C.

A structured technique for saying "good-bye," or terminating a relationship, an important aspect of the therapeutic relationship, is presented. It consists of three distinct phases that are all dynamically interrelated, and can also be structured into separation caused by death. The technique is described in terms of three specific areas…

Bonding and Structure. Independent Learning Project for Advanced Chemistry (ILPAC). Unit S4.

ERIC Educational Resources Information Center

Inner London Education Authority (England).

This unit on chemical bonding is one of 10 first year units produced by the Independent Learning Project for Advanced Chemistry (ILPAC). The unit, which consists of two levels, provides an introduction to the main types of chemical bonding and important aspects of structure. The main emphasis is placed on such topics as ionic and covalent bonding,…

Symmetric tridiagonal structure preserving finite element model updating problem for the quadratic model

NASA Astrophysics Data System (ADS)

Rakshit, Suman; Khare, Swanand R.; Datta, Biswa Nath

2018-07-01

One of the most important yet difficult aspect of the Finite Element Model Updating Problem is to preserve the finite element inherited structures in the updated model. Finite element matrices are in general symmetric, positive definite (or semi-definite) and banded (tridiagonal, diagonal, penta-diagonal, etc.). Though a large number of papers have been published in recent years on various aspects of solutions of this problem, papers dealing with structure preservation almost do not exist. A novel optimization based approach that preserves the symmetric tridiagonal structures of the stiffness and damping matrices is proposed in this paper. An analytical expression for the global minimum solution of the associated optimization problem along with the results of numerical experiments obtained by both the analytical expressions and by an appropriate numerical optimization algorithm are presented. The results of numerical experiments support the validity of the proposed method.

Fiber Tracts of the Medial and Inferior Surfaces of the Cerebrum.

PubMed

Baydin, Serhat; Gungor, Abuzer; Tanriover, Necmettin; Baran, Oguz; Middlebrooks, Erik H; Rhoton, Albert L

2017-02-01

Fiber dissection studies of the cerebrum have focused on the lateral surface. No comparable detailed studies have been done on the medial and inferior surfaces. The object of this study was to examine the fiber tracts, cortical, and subcortical structures of the medial and inferior aspects of the brain important in planning operative approaches along the interhemispheric fissure, parafalcine area, and basal surfaces of the cerebrum. Twenty formalin-fixed human hemispheres (10 brains) were examined by fiber dissection technique under ×6-×40 magnifications. The superior longitudinal fasciculus I, cingulum, inferior longitudinal fasciculus, uncinate fasciculus, optic radiations, tapetum, and callosal fibers were dissected step by step from medial to lateral, exposing the nucleus accumbens, subthalamic nucleus, red nucleus, and central midline structures (fornix, stria medullaris, and stria terminalis). Finally, the central core structures were dissected from medial to lateral. Understanding the fiber network underlying the medial and inferior aspects of the brain is important in surgical planning for approaches along the interhemispheric fissure, parafalcine area, and basal surfaces of the cerebrum. Copyright © 2016. Published by Elsevier Inc.

The emergence, structure and development of ethnic identity during childhood: the case of Roma identity.

PubMed

Pnevmatikos, Dimitris; Geka, Maria; Divane, Maria

2010-12-01

This study investigates the emergence, development and structure of ethnic identity during childhood. Forty Roma children living in Greece aged between 2.8 and 11.9 years answered questions about their awareness/recognition of four aspects of their ethnic identity-namely place of habitation, traditional costumes, the Roma language, and early betrothal of children-their identity and their sense of stability and constancy. The study also investigates how the children feel about the abandonment of those four aspects. The evidence from the current data supports the hypothesis that awareness of ethnic identity emerges before the age of 4. Moreover, this study offers direct empirical evidence of the multidimensionality of ethnic identity. A model of three concentric rings is proposed, extending from a core containing the most highly valued aspects of ethnic identity to the outer annulus that comprises the nonpermanent and nonstable aspects of ethnic identity. The aspects in each annulus differ in terms of the development of the sense of stability and constancy and the feelings associated with loss of the aspects in question. Even the youngest participants considered the aspects in the core to be stable and constant as well as emotionally charged; and even the 11-year-olds did not consider the aspects contained in the outer, more fluid annulus as stable and constant aspects of their ethnic identity. The development of an aspect is determined by what the majority of adults in a society, at a particular time in history, consider to be most important.

Measuring patients' experiences with palliative care: the Consumer Quality Index Palliative Care.

PubMed

Claessen, Susanne J J; Francke, Anneke L; Sixma, Herman J; de Veer, Anke J E; Deliens, Luc

2012-12-01

The Consumer Quality Index Palliative Care (CQ-index PC) is a structured questionnaire for measuring the quality of palliative care from the perspective of care users. CQ-indices assess which care aspects need quality improvement by relating answers about actual care experiences to answers about the importance of certain aspects of care. To improve the chance that the new instrument has good content validity, a literature study and individual and group discussions were performed, and a steering committee was consulted to establish the instrument's face and content validity. The questionnaire was administered to patients with a life expectancy of 6 months or less and/or who were receiving palliative treatment. Descriptive analyses were carried out on the items about actual care experiences and the importance of care aspects, and on 'need for improvement' scores. 15 care organisations participated. 133 patients met the inclusion criteria (net response n=85). Patients considered the following aspects the most important: 'offering help in good time in acute situations', 'caregivers having the necessary expertise' and 'caregivers taking the patient seriously'. The three care aspects with the highest 'need for improvement' scores were: 'support when the patient feels depressed', 'support when the patient is anxious' and 'support when the patient has shortness of breath'. The CQ-index PC provides opportunities for care organisations to assess which care aspects have the highest priority for quality improvement within their organisation. Further research is needed to assess whether the instrument has enough discriminative power to assess differences between organisations.

Measuring Children's Perceptions of Parental Involvement in Conjoint Behavioral Consultation: Factor Structure and Reliability of the "Parental Support for Learning Scale"

ERIC Educational Resources Information Center

Rogers, Maria; Markel, Clarisa; Midgett, Jonathan D.; Ryan, Bruce A.; Tannock, Rosemary

2014-01-01

Practitioners of Conjoint Behavioral Consultation rely on several sources of information to assist in planning and evaluation of consultation efforts. Parental involvement in the home is an important aspect in Conjoint Behavioral Consultation, yet there are few questionnaires available to practitioners to assess this important construct,…

Sexual dimorphism in multiple aspects of 3D facial symmetry and asymmetry defined by spatially dense geometric morphometrics.

PubMed

Claes, Peter; Walters, Mark; Shriver, Mark D; Puts, David; Gibson, Greg; Clement, John; Baynam, Gareth; Verbeke, Geert; Vandermeulen, Dirk; Suetens, Paul

2012-08-01

Accurate measurement of facial sexual dimorphism is useful to understanding facial anatomy and specifically how faces influence, and have been influenced by, sexual selection. An important facial aspect is the display of bilateral symmetry, invoking the need to investigate aspects of symmetry and asymmetry separately when examining facial shape. Previous studies typically employed landmarks that provided only a sparse facial representation, where different landmark choices could lead to contrasting outcomes. Furthermore, sexual dimorphism is only tested as a difference of sample means, which is statistically the same as a difference in population location only. Within the framework of geometric morphometrics, we partition facial shape, represented in a spatially dense way, into patterns of symmetry and asymmetry, following a two-factor anova design. Subsequently, we investigate sexual dimorphism in symmetry and asymmetry patterns separately, and on multiple aspects, by examining (i) population location differences as well as differences in population variance-covariance; (ii) scale; and (iii) orientation. One important challenge in this approach is the proportionally high number of variables to observations necessitating the implementation of permutational and computationally feasible statistics. In a sample of gender-matched young adults (18-25 years) with self-reported European ancestry, we found greater variation in male faces than in women for all measurements. Statistically significant sexual dimorphism was found for the aspect of location in both symmetry and asymmetry (directional asymmetry), for the aspect of scale only in asymmetry (magnitude of fluctuating asymmetry) and, in contrast, for the aspect of orientation only in symmetry. Interesting interplays with hypotheses in evolutionary and developmental biology were observed, such as the selective nature of the force underpinning sexual dimorphism and the genetic independence of the structural patterns of fluctuating asymmetry. Additionally, insights into growth patterns of the soft tissue envelope of the face and underlying skull structure can also be obtained from the results. © 2012 The Authors. Journal of Anatomy © 2012 Anatomical Society.

Sexual dimorphism in multiple aspects of 3D facial symmetry and asymmetry defined by spatially dense geometric morphometrics

PubMed Central

Claes, Peter; Walters, Mark; Shriver, Mark D; Puts, David; Gibson, Greg; Clement, John; Baynam, Gareth; Verbeke, Geert; Vandermeulen, Dirk; Suetens, Paul

2012-01-01

Accurate measurement of facial sexual dimorphism is useful to understanding facial anatomy and specifically how faces influence, and have been influenced by, sexual selection. An important facial aspect is the display of bilateral symmetry, invoking the need to investigate aspects of symmetry and asymmetry separately when examining facial shape. Previous studies typically employed landmarks that provided only a sparse facial representation, where different landmark choices could lead to contrasting outcomes. Furthermore, sexual dimorphism is only tested as a difference of sample means, which is statistically the same as a difference in population location only. Within the framework of geometric morphometrics, we partition facial shape, represented in a spatially dense way, into patterns of symmetry and asymmetry, following a two-factor anova design. Subsequently, we investigate sexual dimorphism in symmetry and asymmetry patterns separately, and on multiple aspects, by examining (i) population location differences as well as differences in population variance-covariance; (ii) scale; and (iii) orientation. One important challenge in this approach is the proportionally high number of variables to observations necessitating the implementation of permutational and computationally feasible statistics. In a sample of gender-matched young adults (18–25 years) with self-reported European ancestry, we found greater variation in male faces than in women for all measurements. Statistically significant sexual dimorphism was found for the aspect of location in both symmetry and asymmetry (directional asymmetry), for the aspect of scale only in asymmetry (magnitude of fluctuating asymmetry) and, in contrast, for the aspect of orientation only in symmetry. Interesting interplays with hypotheses in evolutionary and developmental biology were observed, such as the selective nature of the force underpinning sexual dimorphism and the genetic independence of the structural patterns of fluctuating asymmetry. Additionally, insights into growth patterns of the soft tissue envelope of the face and underlying skull structure can also be obtained from the results. PMID:22702244

Methodology of homogeneous and non-homogeneous Markov Chains for modeling bridge element deterioration.

DOT National Transportation Integrated Search

2008-08-01

Bridge management is an important activity of transportation agencies in the US : and in many other countries. A critical aspect of bridge management is to reliably predict : the deterioration of bridge structures, so that appropriate or optimal acti...

Local knowledge of traditional fishermen on economically important crabs (Decapoda: Brachyura) in the city of Conde, Bahia State, Northeastern Brazil.

PubMed

de Magalhães, Henrique Fernandes; Costa Neto, Eraldo Medeiros; Schiavetti, Alexandre

2012-07-02

This article records the traditional knowledge of crab gatherers in the city of Conde, in the North Coast Region of Bahia State, Northeastern Brazil. Data on biological and ecological aspects of economically important brachyuran crustaceans have been obtained from semi-structured interviews and in loco observations conducted from September 2007 to December 2009. A total of 57 fishermen of both genders, aged between 10 and 78 years have been interviewed (individually or collectively) in different contexts; interviewees were asked about aspects such as external morphology, life cycle, trophic ecology, and spatial and temporal distribution of the major economically important brachyuran crustaceans in the region. Seven fishing communities were visited: Siribinha, Sítio do Conde, Poças, Ilha das Ostras, Cobó, Buri and Sempre Viva. Data were analyzed by comparing the information provided by participants with those from the specialized academic literature. The results show that artisanal fishermen have a wide ranging and well-grounded knowledge on the ecological and biological aspects of crustaceans. Crab gatherers of Conde know about growth and reproductive behavior of the animals they interact with, especially with regard to the three major biological aspects: "molt", "walking dance" and "spawning". This knowledge constitutes an important source of information that should be considered in studies of management and sustainable use of fishery resources in the North Coast Region of Bahia State.

Collisionless microtearing modes in hot tokamaks: Effect of trapped electrons

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

Swamy, Aditya K.; Ganesh, R., E-mail: ganesh@ipr.res.in; Brunner, S.

2015-07-15

Collisionless microtearing modes have recently been found linearly unstable in sharp temperature gradient regions of large aspect ratio tokamaks. The magnetic drift resonance of passing electrons has been found to be sufficient to destabilise these modes above a threshold plasma β. A global gyrokinetic study, including both passing electrons as well as trapped electrons, shows that the non-adiabatic contribution of the trapped electrons provides a resonant destabilization, especially at large toroidal mode numbers, for a given aspect ratio. The global 2D mode structures show important changes to the destabilising electrostatic potential. The β threshold for the onset of the instabilitymore » is found to be generally downshifted by the inclusion of trapped electrons. A scan in the aspect ratio of the tokamak configuration, from medium to large but finite values, clearly indicates a significant destabilizing contribution from trapped electrons at small aspect ratio, with a diminishing role at larger aspect ratios.« less

BUREAUCRATIC STRUCTURE AND DECISIONMAKING.

ERIC Educational Resources Information Center

DOWNS, ANTHONY

ASPECTS OF ORGANIZATION THEORY ARE REVIEWED ANALYTICALLY TO DEVELOP THE IMPLICATIONS OF THREE MAJOR HYPOTHESES DEFINING THE RELATIONSHIP OF BUREAUS AND BUREAUCRATIC OFFICIALS TO THE DECISIONMAKING PROCESS IN A REALISTIC WORLD WHERE INFORMATION IS COSTLY AND UNCERTAINTY IS AN IMPORTANT FACTOR IN MAKING DECISIONS--(1) BUREAUCRATIC OFFICIALS SEEK TO…

Aquaporins and root water uptake

USDA-ARS?s Scientific Manuscript database

Water is one of the most critical resources limiting plant growth and crop productivity, and root water uptake is an important aspect of plant physiology governing plant water use and stress tolerance. Pathways of root water uptake are complex and are affected by root structure and physiological res...

Aspects of Financing Non-Formal Education.

ERIC Educational Resources Information Center

Morales, Francisco X. Swett

1983-01-01

Various financing structures for nonformal education are presented, using examples from Colombia, Brazil, Costa Rica, and Ecuador. Many resources of the formal education system can be used in the planning, coordination, and execution of nonformal education. The importance of community involvement and financial backing is stressed. (JA)

Nuclear Structure Aspects in Nuclear Astrophysics

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

Smith, Michael Scott

2006-12-01

Nuclear Astrophysics as a broad and diverse field of study can be viewed as a magnifier of the impact of microscopic processes on the evolution of macroscopic events. One of the primary goals in Nuclear Astrophysics is the understanding of the nucleosynthesis processes that take place in the cosmos and the simulation of the correlated stellar and explosive burning scenarios. These simulations are strongly dependent on the input from Nuclear Physics which sets the time scale for all stellar dynamic processes--from giga-years of stellar evolution to milliseconds of stellar explosions--and provides the basis for most of the signatures that wemore » have for the interpretation of these events--from stellar luminosities, elemental and isotopic abundances to neutrino flux from distant supernovae. The Nuclear Physics input comes through nuclear structure, low energy reaction rates, nuclear masses, and decay rates. There is a common perception that low energy reaction rates are the most important component of the required nuclear physics input; however, in this article we take a broader approach and present an overview of the close correlation between various nuclear structure aspects and their impact on nuclear astrophysics. We discuss the interplay between the weak and the strong forces on stellar time scales due to the limitations they provide for the evolution of slow and rapid burning processes. The effects of shell structure in nuclei on stellar burning processes as well as the impact of clustering in nuclei is outlined. Furthermore we illustrate the effects of the various nuclear structure aspects on the major nucleosynthesis processes that have been identified in the last few decades. We summarize and provide a coherent overview of the impact of all aspects of nuclear structure on nuclear astrophysics.« less

A knowledge representation view on biomedical structure and function.

PubMed Central

Schulz, Stefan; Hahn, Udo

2002-01-01

In biomedical ontologies, structural and functional considerations are of outstanding importance, and concepts which belong to these two categories are highly interdependent. At the representational level both axes must be clearly kept separate in order to support disciplined ontology engineering. Furthermore, the biaxial organization of physical structure (both by a taxonomic and partonomic order) entails intricate patterns of inference. We here propose a layered encoding of taxonomic, partonomic and functional aspects of biomedical concepts using description logics. PMID:12463912

An effective introduction to structural crystallography using 1D Gaussian atoms

NASA Astrophysics Data System (ADS)

Smith, Emily; Evans, Gwyndaf; Foadi, James

2017-11-01

The most important quantitative aspects of computational structural crystallography can be introduced in a satisfactory way using 1D truncated and periodic Gaussian functions to represent the atoms in a crystal lattice. This paper describes in detail and demonstrates 1D structural crystallography starting with the definition of such truncated Gaussians. The availability of the computer programme CRONE makes possible the repetition of the examples provided in the paper as well as the creation of new ones.

Structural Pain Compensating Flight Control

NASA Technical Reports Server (NTRS)

Miller, Chris J.

2014-01-01

The problem of control command and maneuver induced structural loads is an important aspect of any control system design. Designers must design the aircraft structure and the control architecture to achieve desired piloted control responses while limiting the imparted structural loads. The classical approach is to build the structure with high margins, restrict control surface commands to known good combinations, and train pilots to follow procedural maneuvering limitations. With recent advances in structural sensing and the continued desire to improve safety and vehicle fuel efficiency, it is both possible and desirable to develop control architectures that enable lighter vehicle weights while maintaining and improving protection against structural damage.

Pulsed ultrasonic instruments for monitoring the strength of materials

NASA Astrophysics Data System (ADS)

Korolev, Mikhail Viktorovich; Starikov, Boris Pavlovich; Karpel'Son, Arkadii Efimovich

The book is concerned with various aspects of the design of portable instruments for the ultrasonic monitoring of the strength and ductile characteristics of structural materials, including metals, alloys, and ceramics. Particular attention is given to methods for increasing the accuracy of the instruments while reducing their size, which is particularly important in the design of miniature instruments for the real-time monitoring of machines, mechanisms, and structures during operation.

Reopening Openness to Experience: A Network Analysis of Four Openness to Experience Inventories.

PubMed

Christensen, Alexander P; Cotter, Katherine N; Silvia, Paul J

2018-05-10

Openness to Experience is a complex trait, the taxonomic structure of which has been widely debated. Previous research has provided greater clarity of its lower order structure by synthesizing facets across several scales related to Openness to Experience. In this study, we take a finer grained approach by investigating the item-level relations of four Openness to Experience inventories (Big Five Aspects Scale, HEXACO-100, NEO PI-3, and Woo et al.'s Openness to Experience Inventory), using a network science approach, which allowed items to form an emergent taxonomy of facets and aspects. Our results (N = 802) identified 10 distinct facets (variety-seeking, aesthetic appreciation, intellectual curiosity, diversity, openness to emotions, fantasy, imaginative, self-assessed intelligence, intellectual interests, and nontraditionalism) that largely replicate previous findings as well as three higher order aspects: two that are commonly found in the literature (intellect and experiencing; i.e., openness), and one novel aspect (open-mindedness). In addition, we demonstrate that each Openness to Experience inventory offers a unique conceptualization of the trait, and that some inventories provide broader coverage of the network space than others. Our findings establish a broader consensus of Openness to Experience at the aspect and facet level, which has important implications for researchers and the Openness to Experience inventories they use.

[Organization of socially acceptable working hours in nursing].

PubMed

Büssing, A; Glaser, J

1994-05-01

Three dimensions in the structure of the working hour system of nurses, rendering them socially acceptable, are becoming important: duration of the working day, the time of day which is being worked and the distribution of working hours. The latter two are of particular importance because flexible shift is becoming the dominant pattern in nursing. Six indicators are discussed as criteria for social acceptability: security of employment which includes access to the labour-market, level of income, health, opportunity for social relationships, social participation, and autonomy. Responses of 297 nurses in one General Hospital taking part in a study, were analysed to examine empirically the concept of 'socially acceptable structure of the working hours'. Ideal and factual patterns are considered first. Secondly aspects of autonomy are considered and the way this depends on time, thirdly the criteria used to define 'social acceptability' are examined for validity. Results show firstly the cross contrast between the hospital's expectation and the nurses' wishes with regard to working hours. Furthermore, inspite of the demand for flexibility, staff have very little choice and there is little sign of joint decision making. Thirdly results show that health, interpersonal and social aspects are of special importance and that, correspondingly, in the view of nurses, financial and practical problems are of lesser importance in their every day life.

Historic surface faulting in continental United States and adjacent parts of Mexico

USGS Publications Warehouse

Bonilla, M.G.

1967-01-01

This report summarizes geometric aspects of approximately 35 instances of historic faulting of the ground surface in the continental United States and adjacent parts of Mexico. This information is of immediate importance in the selection and evaluation of sites for vital structures such as nuclear power plants. The data are presented in a table and graphs which show the quantitative relations between various aspects of the faulting. Certain items in the table that are uncertain, poorly known, or not in the published literature are briefly described in the text.

Cognitive Issues in Learning Advanced Physics: An Example from Quantum Mechanics

NASA Astrophysics Data System (ADS)

Singh, Chandralekha; Zhu, Guangtian

2009-11-01

We are investigating cognitive issues in learning quantum mechanics in order to develop effective teaching and learning tools. The analysis of cognitive issues is particularly important for bridging the gap between the quantitative and conceptual aspects of quantum mechanics and for ensuring that the learning tools help students build a robust knowledge structure. We discuss the cognitive aspects of quantum mechanics that are similar or different from those of introductory physics and their implications for developing strategies to help students develop a good grasp of quantum mechanics.

Deterioration of concrete structures in coastal environment due to carbonation.

PubMed

Balaji, K V G D; Gopalaraju, S S S V; Trilochan, Jena

2010-07-01

Failure of existing concrete structures takes place due to lack of durability, and not due to less structural strength. One of the important aspects of durability is carbonation depth. The rate of carbonation in concrete is influenced by both its physical properties and exposure conditions. Rebar corrodes when carbonation reaches to a depth of concrete cover provided. In the present work, various concrete structures with different life periods and exposed to different weather conditions have been considered to study the carbonation effect. It is observed that the effect of carbonation is more in the structures located near to the sea coast and on windward face of the structure.

The relative influence of habitat amount and configuration on genetic structure across multiple spatial scales

PubMed Central

Millette, Katie L; Keyghobadi, Nusha

2015-01-01

Despite strong interest in understanding how habitat spatial structure shapes the genetics of populations, the relative importance of habitat amount and configuration for patterns of genetic differentiation remains largely unexplored in empirical systems. In this study, we evaluate the relative influence of, and interactions among, the amount of habitat and aspects of its spatial configuration on genetic differentiation in the pitcher plant midge, Metriocnemus knabi. Larvae of this species are found exclusively within the water-filled leaves of pitcher plants (Sarracenia purpurea) in a system that is naturally patchy at multiple spatial scales (i.e., leaf, plant, cluster, peatland). Using generalized linear mixed models and multimodel inference, we estimated effects of the amount of habitat, patch size, interpatch distance, and patch isolation, measured at different spatial scales, on genetic differentiation (FST) among larval samples from leaves within plants, plants within clusters, and clusters within peatlands. Among leaves and plants, genetic differentiation appears to be driven by female oviposition behaviors and is influenced by habitat isolation at a broad (peatland) scale. Among clusters, gene flow is spatially restricted and aspects of both the amount of habitat and configuration at the focal scale are important, as is their interaction. Our results suggest that both habitat amount and configuration can be important determinants of genetic structure and that their relative influence is scale dependent. PMID:25628865

The relative influence of habitat amount and configuration on genetic structure across multiple spatial scales.

PubMed

Millette, Katie L; Keyghobadi, Nusha

2015-01-01

Despite strong interest in understanding how habitat spatial structure shapes the genetics of populations, the relative importance of habitat amount and configuration for patterns of genetic differentiation remains largely unexplored in empirical systems. In this study, we evaluate the relative influence of, and interactions among, the amount of habitat and aspects of its spatial configuration on genetic differentiation in the pitcher plant midge, Metriocnemus knabi. Larvae of this species are found exclusively within the water-filled leaves of pitcher plants (Sarracenia purpurea) in a system that is naturally patchy at multiple spatial scales (i.e., leaf, plant, cluster, peatland). Using generalized linear mixed models and multimodel inference, we estimated effects of the amount of habitat, patch size, interpatch distance, and patch isolation, measured at different spatial scales, on genetic differentiation (F ST) among larval samples from leaves within plants, plants within clusters, and clusters within peatlands. Among leaves and plants, genetic differentiation appears to be driven by female oviposition behaviors and is influenced by habitat isolation at a broad (peatland) scale. Among clusters, gene flow is spatially restricted and aspects of both the amount of habitat and configuration at the focal scale are important, as is their interaction. Our results suggest that both habitat amount and configuration can be important determinants of genetic structure and that their relative influence is scale dependent.

Guidelines to Literature Study in the Junior High School.

ERIC Educational Resources Information Center

Dade County Board of Public Instruction, Miami, FL.

GRADES OR AGES: Junior high school (grades 7-9). SUBJECT MATTER: Literature. ORGANIZATION AND PHYSICAL APPEARANCE: The contents of the guide are 1) major objectives, important aspects of the nature of literature, organization of literature study, ways of structuring reading for the individual student, implications of teaching reading skills,…

Tropical Rainforest Education. ERIC Digest.

ERIC Educational Resources Information Center

Rillero, Peter

This digest provides four guideposts for tropical rainforest education: (1) structure; (2) location and climate; (3) importance; and (4) conservation of resources. Research is cited and background information provided about the layers of life and the adaptations of life within the tropical rain forest. Aspects of life within and near rain forests…

Specification Theory, Patterns, and Models in Information Systems Domains: An Exploratory Investigation

ERIC Educational Resources Information Center

Woolridge, Richard William

2010-01-01

Application and project domain specifications are an important aspect of Information Systems (IS) development. Observations of over thirty IS projects suggest dimly perceived structural patterns in specifications that are unaccounted for in research and practice. This investigation utilizes a theory building with case studies methodology to…

Facile fabrication of nanofluidic diode membranes using anodic aluminium oxide

NASA Astrophysics Data System (ADS)

Wu, Songmei; Wildhaber, Fabien; Vazquez-Mena, Oscar; Bertsch, Arnaud; Brugger, Juergen; Renaud, Philippe

2012-08-01

Active control of ion transport plays important roles in chemical and biological analytical processes. Nanofluidic systems hold the promise for such control through electrostatic interaction between ions and channel surfaces. Most existing experiments rely on planar geometry where the nanochannels are generally very long and shallow with large aspect ratios. Based on this configuration the concepts of nanofluidic gating and rectification have been successfully demonstrated. However, device minimization and throughput scaling remain significant challenges. We report here an innovative and facile realization of hetero-structured Al2O3/SiO2 (Si) nanopore array membranes by using pattern transfer of self-organized nanopore structures of anodic aluminum oxide (AAO). Thanks to the opposite surface charge states of Al2O3 (positive) and SiO2 (negative), the membrane exhibits clear rectification of ion current in electrolyte solutions with very low aspect ratios compared to previous approaches. Our hetero-structured nanopore arrays provide a valuable platform for high throughput applications such as molecular separation, chemical processors and energy conversion.Active control of ion transport plays important roles in chemical and biological analytical processes. Nanofluidic systems hold the promise for such control through electrostatic interaction between ions and channel surfaces. Most existing experiments rely on planar geometry where the nanochannels are generally very long and shallow with large aspect ratios. Based on this configuration the concepts of nanofluidic gating and rectification have been successfully demonstrated. However, device minimization and throughput scaling remain significant challenges. We report here an innovative and facile realization of hetero-structured Al2O3/SiO2 (Si) nanopore array membranes by using pattern transfer of self-organized nanopore structures of anodic aluminum oxide (AAO). Thanks to the opposite surface charge states of Al2O3 (positive) and SiO2 (negative), the membrane exhibits clear rectification of ion current in electrolyte solutions with very low aspect ratios compared to previous approaches. Our hetero-structured nanopore arrays provide a valuable platform for high throughput applications such as molecular separation, chemical processors and energy conversion. Electronic supplementary information (ESI) available: Pattern transfer of local AAO mask into Si layers of different thickness; characterization of the Ag/AgCl electrodes and the cell constant; control experiments of mono-charged nanopore membranes; and simulation of ionic transport in nanofluidic diodes. See DOI: 10.1039/c2nr31243c

Local knowledge of traditional fishermen on economically important crabs (Decapoda: Brachyura) in the city of Conde, Bahia State, Northeastern Brazil

PubMed Central

2012-01-01

Background This article records the traditional knowledge of crab gatherers in the city of Conde, in the North Coast Region of Bahia State, Northeastern Brazil. Methods Data on biological and ecological aspects of economically important brachyuran crustaceans have been obtained from semi-structured interviews and in loco observations conducted from September 2007 to December 2009. A total of 57 fishermen of both genders, aged between 10 and 78 years have been interviewed (individually or collectively) in different contexts; interviewees were asked about aspects such as external morphology, life cycle, trophic ecology, and spatial and temporal distribution of the major economically important brachyuran crustaceans in the region. Seven fishing communities were visited: Siribinha, Sítio do Conde, Poças, Ilha das Ostras, Cobó, Buri and Sempre Viva. Data were analyzed by comparing the information provided by participants with those from the specialized academic literature. Results The results show that artisanal fishermen have a wide ranging and well-grounded knowledge on the ecological and biological aspects of crustaceans. Crab gatherers of Conde know about growth and reproductive behavior of the animals they interact with, especially with regard to the three major biological aspects: “molt”, “walking dance” and “spawning”. Conclusion This knowledge constitutes an important source of information that should be considered in studies of management and sustainable use of fishery resources in the North Coast Region of Bahia State. PMID:22449069

Safe mobility for elderly drivers--considerations based on expert and self-assessment.

PubMed

Broberg, Thomas; Dukic Willstrand, Tania

2014-05-01

To further understand the needs of the growing population of elderly drivers and create solutions for safe mobility it is important to understand the driving scenarios and aspects in day to day traffic that may be of challenge for this group. More so, individual differences in how drivers perceive their own driving ability may have an effect on how individuals limit their mobility and/or increase their exposure to risk situations, with a potential negative effect on safety. In this study two sets of assessments have been used in order to identify scenarios and aspects needing consideration in creating safe mobility for elderly drivers; an expert assessment using on-road driving together with assessments through semi structured in-depth interviews. This combination also enables categorisation of the drivers, comparing their own perception of their driving performance with the expert assessment based on actual on-road driving. Four different categories of drivers were identified: adequate (positive), over, under and adequate (negative) estimators. A number of important aspects were identified in the study. Adapting speed to the situation and driving too fast, especially on straight roads in the city, is one aspect. Seeking the attention of other road users at intersections and roundabouts is another important consideration identified. Awareness of difficulties related to speed adaptation and attention was low amongst all the driver categories. However, a difference in attitude was seen in the categories with a more humble and acceptant attitude amongst the adequate and under estimator groups, as compared to the over estimators suggesting that the aspect of attitudes is another important factor for consideration. Copyright © 2014 Elsevier Ltd. All rights reserved.

Intersection between metabolic dysfunction, high fat diet consumption, and brain aging.

PubMed

Uranga, Romina M; Bruce-Keller, Annadora J; Morrison, Christopher D; Fernandez-Kim, Sun Ok; Ebenezer, Philip J; Zhang, Le; Dasuri, Kalavathi; Keller, Jeffrey N

2010-07-01

Deleterious neurochemical, structural, and behavioral alterations are a seemingly unavoidable aspect of brain aging. However, the basis for these alterations, as well as the basis for the tremendous variability in regards to the degree to which these aspects are altered in aging individuals, remains to be elucidated. An increasing number of individuals regularly consume a diet high in fat, with high-fat diet consumption known to be sufficient to promote metabolic dysfunction, although the links between high-fat diet consumption and aging are only now beginning to be elucidated. In this review we discuss the potential role for age-related metabolic disturbances serving as an important basis for deleterious perturbations in the aging brain. These data not only have important implications for understanding the basis of brain aging, but also may be important to the development of therapeutic interventions which promote successful brain aging.

XVII International Conference on Hadron Spectroscopy and Structure

NASA Astrophysics Data System (ADS)

2017-09-01

The Hadron 2017 Conference is the seventeenth of a series of biennial conferences started in 1985 at Maryland, USA. Its official name, XVII International Conference on Hadron Spectroscopy and Structure, includes for the first time the term structure to emphasize the importance that this issue has acquired in recent editions of the series. The aim of the conference is to provide an overview of the present status and progress in hadron structure and dynamics, as well as a preview of the forthcoming investigations. It will cover lectures on both experimental and theoretical aspects, including in particular the presentation of new results.

Voids and the Cosmic Web: cosmic depression & spatial complexity

NASA Astrophysics Data System (ADS)

van de Weygaert, Rien

2016-10-01

Voids form a prominent aspect of the Megaparsec distribution of galaxies and matter. Not only do theyrepresent a key constituent of the Cosmic Web, they also are one of the cleanest probesand measures of global cosmological parameters. The shape and evolution of voids are highly sensitive tothe nature of dark energy, while their substructure and galaxy population provides a direct key to thenature of dark matter. Also, the pristine environment of void interiors is an important testing groundfor our understanding of environmental influences on galaxy formation and evolution. In this paper, we reviewthe key aspects of the structure and dynamics ofvoids, with a particular focus on the hierarchical evolution of the void population. We demonstratehow the rich structural pattern of the Cosmic Web is related to the complex evolution and buildupof voids.

Molecular insights into the novel aspects of diatom biology.

PubMed

Scala, S; Bowler, C

2001-10-01

Diatoms are unicellular photosynthetic eukaryotes that are thought to contribute as much as 25% of global primary productivity. In spite of their ecological importance in the worlds oceans, very little information is available at the molecular level about the novel aspects of their biology. Recent advances, such as the development of gene transfer protocols, are now allowing the genetic dissection of diatom biology. Notable examples are advances in understanding the genetic basis for the silica-based bioinorganic pattern formation of their cell walls and for elucidating key aspects of diatom ecophysiology. The potentiation of current research will allow an evaluation of the use of diatoms to construct submicrometre-scale silicon structures for the nanotechnology industry and will reveal the molecular secrets underlying their ecological success.

Cross-sectional aspect ratio modulated electronic properties in Si/Ge core/shell nanowires

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

Liu, Nuo; Lu, Ning; Yao, Yong-Xin

2013-02-28

Electronic structures of (4, n) and (m, 4) (the NW has m layers parallel to the {1 1 1} facet and n layers parallel to {1 1 0}) Si/Ge core/shell nanowires (NWs) along the [1 1 2] direction with cross-sectional aspect ratio (m/n) from 0.36 to 2.25 are studied by first-principles calculations. An indirect to direct band gap transition is observed as m/n decreases, and the critical values of m/n and diameter for the transition are also estimated. The size of the band gap also depends on the aspect ratio. These results suggest that m/n plays an important role inmore » modulating the electronic properties of the NWs.« less

Structural Design Exploration of an Electric Powered Multi-Propulsor Wing Configuration

NASA Technical Reports Server (NTRS)

Moore, James B.; Cutright, Steve

2017-01-01

Advancements in aircraft electric propulsion may enable an expanded operational envelope for electrically powered vehicles compared to their internal combustion engine counterparts. High aspect ratio wings provide additional lift and drag reduction for a proposed multi-propulsor design, however, the challenge is to reduce the weight of wing structures while maintaining adequate structural and aeroelastic margins. Design exploration using a conventional design-and-build philosophy coupled with a finite element method (FEM)-based design of experiments (DOE) strategy are presented to examine high aspect ratio wing structures that have spanwise distributed electric motors. Multiple leading-edge-mounted engine masses presented a challenge to design a wing within acceptable limits for dynamic and aeroelastic stability. Because the first four primary bending eigenmodes of the proposed wing structure are very sensitive to outboard motor placement, safety-of-flight requirements drove the need for multiple spars, rib attachments, and outboard structural reinforcements in the design. Global aeroelasticity became an increasingly important design constraint during the on-going design process, with outboard motor pod flutter ultimately becoming a primary design constraint. Designers successively generated models to examine stress, dynamics, and aeroelasticity concurrently. This research specifically addressed satisfying multi-disciplinary design criteria to generate fluid-structure interaction solution sets, and produced high aspect ratio primary structure designs for the NASA Scalable Convergent Electric Propulsion Technology and Operations Research (SCEPTOR) project in the Aeronautic Research Mission Directorate at NASA. In this paper, a dynamics-driven, quasi-inverse design methodology is presented to address aerodynamic performance goals and structural challenges encountered for the SCEPTOR demonstrator vehicle. These results are compared with a traditional computer aided design based approach.

The metabolism of structured triacylglycerols.

PubMed

Mu, Huiling; Porsgaard, Trine

2005-11-01

The triacylglycerol (TAG) structure in addition to the overall fatty acid profile is of importance when considering the nutritional effect of a dietary fat. This review aims at summarizing our current knowledge of the digestion, absorption, uptake, and transport of structured TAGs, with particular emphasis on the following aspects: gastric emptying, specificity of pancreatic lipase, lymphatic transport and clearance of chylomicrons, effects of lipid structure on tissue lipid compositions and the fecal loss of fats. So an overview will be provided for how the structure and fatty acid composition of TAGs affect their absorption and the distribution of the fatty acids in the body following digestion and absorption.

Application of high explosion cratering data to planetary problems

NASA Technical Reports Server (NTRS)

Oberbeck, V. R.

1977-01-01

The present paper deals with the conditions of explosion or nuclear cratering required to simulate impact crater formation. Some planetary problems associated with three different aspects of crater formation are discussed, and solutions based on high-explosion data are proposed. Structures of impact craters and some selected explosion craters formed in layered media are examined and are related to the structure of lunar basins. The mode of ejection of material from impact craters is identified using explosion analogs. The ejection mode is shown to have important implications for the origin of material in crater and basin deposits. Equally important are the populations of secondary craters on lunar and planetary surfaces.

A Systematic Review of Health Economics Simulation Models of Chronic Obstructive Pulmonary Disease.

PubMed

Zafari, Zafar; Bryan, Stirling; Sin, Don D; Conte, Tania; Khakban, Rahman; Sadatsafavi, Mohsen

2017-01-01

Many decision-analytic models with varying structures have been developed to inform resource allocation in chronic obstructive pulmonary disease (COPD). To review COPD models for their adherence to the best practice modeling recommendations and their assumptions regarding important aspects of the natural history of COPD. A systematic search of English articles reporting on the development or application of a decision-analytic model in COPD was performed in MEDLINE, Embase, and citations within reviewed articles. Studies were summarized and evaluated on the basis of their adherence to the Consolidated Health Economic Evaluation Reporting Standards. They were also evaluated for the underlying assumptions about disease progression, heterogeneity, comorbidity, and treatment effects. Forty-nine models of COPD were included. Decision trees and Markov models were the most popular techniques (43 studies). Quality of reporting and adherence to the guidelines were generally high, especially in more recent publications. Disease progression was modeled through clinical staging in most studies. Although most studies (n = 43) had incorporated some aspects of COPD heterogeneity, only 8 reported the results across subgroups. Only 2 evaluations explicitly considered the impact of comorbidities. Treatment effect had been mostly modeled (20) as both reduction in exacerbation rate and improvement in lung function. Many COPD models have been developed, generally with similar structural elements. COPD is highly heterogeneous, and comorbid conditions play an important role in its burden. These important aspects, however, have not been adequately addressed in most of the published models. Copyright © 2017 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Using hybrid method to evaluate the green performance in uncertainty.

PubMed

Tseng, Ming-Lang; Lan, Lawrence W; Wang, Ray; Chiu, Anthony; Cheng, Hui-Ping

2011-04-01

Green performance measure is vital for enterprises in making continuous improvements to maintain sustainable competitive advantages. Evaluation of green performance, however, is a challenging task due to the dependence complexity of the aspects, criteria, and the linguistic vagueness of some qualitative information and quantitative data together. To deal with this issue, this study proposes a novel approach to evaluate the dependence aspects and criteria of firm's green performance. The rationale of the proposed approach, namely green network balanced scorecard, is using balanced scorecard to combine fuzzy set theory with analytical network process (ANP) and importance-performance analysis (IPA) methods, wherein fuzzy set theory accounts for the linguistic vagueness of qualitative criteria and ANP converts the relations among the dependence aspects and criteria into an intelligible structural modeling used IPA. For the empirical case study, four dependence aspects and 34 green performance criteria for PCB firms in Taiwan were evaluated. The managerial implications are discussed.

Molecular Aspects of Structure, Gating, and Physiology of pH-Sensitive Background K2P and Kir K+-Transport Channels

PubMed Central

Sepúlveda, Francisco V.; Pablo Cid, L.; Teulon, Jacques; Niemeyer, María Isabel

2015-01-01

K+ channels fulfill roles spanning from the control of excitability to the regulation of transepithelial transport. Here we review two groups of K+ channels, pH-regulated K2P channels and the transport group of Kir channels. After considering advances in the molecular aspects of their gating based on structural and functional studies, we examine their participation in certain chosen physiological and pathophysiological scenarios. Crystal structures of K2P and Kir channels reveal rather unique features with important consequences for the gating mechanisms. Important tasks of these channels are discussed in kidney physiology and disease, K+ homeostasis in the brain by Kir channel-equipped glia, and central functions in the hearing mechanism in the inner ear and in acid secretion by parietal cells in the stomach. K2P channels fulfill a crucial part in central chemoreception probably by virtue of their pH sensitivity and are central to adrenal secretion of aldosterone. Finally, some unorthodox behaviors of the selectivity filters of K2P channels might explain their normal and pathological functions. Although a great deal has been learned about structure, molecular details of gating, and physiological functions of K2P and Kir K+-transport channels, this has been only scratching at the surface. More molecular and animal studies are clearly needed to deepen our knowledge. PMID:25540142

Inducible defenses in food webs: Chapter 3.4

USGS Publications Warehouse

Vos, Matthijs; Kooi, Bob W.; DeAngelis, Donald L.; Mooij, Wolf M.; de Ruiter, Peter; Wolters, Volkmar; Moore, John C.; Melville-Smith, Kimberly

2005-01-01

This chapter reviews the predicted effects of induced defenses on trophic structure and two aspects of stability, “local” stability and persistence, as well as presenting novel results on a third, resilience. Food webs are structures of populations in a given location organized according to their predator–prey interactions. Interaction strengths and, therefore, prey defenses are generally recognized as important ecological factors affecting food webs. Despite this, surprisingly, little light has been shed on the food web-level consequences of inducible defenses. Inducible defenses occur in many taxa in both terrestrial and aquatic food webs. They include refuge use, reduced activity, adaptive life history changes, the production of toxins, synomones and extrafloral nectar, and the formation of colonies, helmets, thorns, or spines. In the chapter, theoretical results for the effects of inducible defenses on trophic structure and the three aspects of stability are reviewed. This is done, in part, using bifurcation analysis—a type of analysis that is applied to nonlinear dynamic systems described by a set of ordinary differential or difference equations. The work presented in the chapter suggests that heterogeneity, as caused by induced defenses in prey species, has major effects on the functioning of food webs. Inducible defenses occur in many species in both aquatic and terrestrial systems, and theoretical work indicates they have major effects on important food web properties such as trophic structure, local stability, persistence, and resilience.

Mathematical methods for protein science

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

Hart, W.; Istrail, S.; Atkins, J.

1997-12-31

Understanding the structure and function of proteins is a fundamental endeavor in molecular biology. Currently, over 100,000 protein sequences have been determined by experimental methods. The three dimensional structure of the protein determines its function, but there are currently less than 4,000 structures known to atomic resolution. Accordingly, techniques to predict protein structure from sequence have an important role in aiding the understanding of the Genome and the effects of mutations in genetic disease. The authors describe current efforts at Sandia to better understand the structure of proteins through rigorous mathematical analyses of simple lattice models. The efforts have focusedmore » on two aspects of protein science: mathematical structure prediction, and inverse protein folding.« less

Structure and anti-structure in the culture-bound syndromes: The Malay case.

PubMed

Lee, R L

1981-09-01

Turner's concepts of structure and anti-structure are applied to the culture-bound syndromes to demonstrate that they are dialectical aspects of cultural reality, The Malay cases of amok, latah and possession hysteria are discussed as instances of anti-structural behaviors that dramatize role-reversals and role-enhancement. The performers of these behaviors are not subjected to the Malay code of moral conduct. The supernatural ethos in Malay culture plays an important role in shaping tolerance towards them. Although this tolerance has been gradually eroded as a result of the introduction of Western psychiatry, the anti-structural status of these syndromes has not faded away but has assumed new meanings in terms of psychopathology.

Nonmetro Poverty: Assessing the Effect of the 1990s.

ERIC Educational Resources Information Center

Jolliffe, Dean

2003-01-01

During the 1990s, the poverty rate in nonmetropolitan areas declined to a record low of 13.4 percent. Drawing on census data, aspects of nonmetro poverty during the 1990s are outlined, including effects of urbanization, regional differences, racial and ethnic differences, importance of family structure, needs for assistance and human services,…

[Anatomy and malformations of the posterior cranial fossa].

PubMed

Struffert, T

2016-11-01

Many important structures are located in the confined space within the posterior cranial fossa. This article describes the main aspects of the anatomy. As a uniform classification of malformations of the posterior cranial fossa does not exist the main syndromes, such as Chiari malformations, zerebellar hypoplasia and dysplasia are discussed separately.

Modeling and Measuring the Structure of Professional Vision in Preservice Teachers

ERIC Educational Resources Information Center

Seidel, Tina; Stürmer, Kathleen

2014-01-01

Professional vision has been identified as an important element of teacher expertise that can be developed in teacher education. It describes the use of knowledge to notice and interpret significant features of classroom situations. Three aspects of professional vision have been described by qualitative research: describe, explain, and predict…

Fire regimes and approaches for determining fire history

Treesearch

James K. Agee

1996-01-01

Fire has been an important evolutionary influence in forests, affecting species composition, structure, and functional aspects of forest biology. Restoration of wildland forests of the future will depend in part on restoring fire to an appropriate role in forest ecosystems. This may include the "range of natural variability" or other concepts associated with...

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

Hawkins, D.

The geopolitical, economic, and cultural aspects of the United States of Mexico are presented. Mexico's energy profile includes the following: energy policy objectives, government energy structure, organizations for implementation, indigeneous energy sources, imported energy sources, solar energy research and development, solar energy organizations and solar energy related legislation and administrative policies. International agreements, contacts, manufacturers, and projects are listed. (MRH)

Relationships between School Climate, Bullying and Delinquent Behaviours

ERIC Educational Resources Information Center

Aldridge, Jill M.; McChesney, Katrina; Afari, Ernest

2018-01-01

Given that schools are, potentially, powerful sites for influencing adolescent behaviour, it is important that there is greater understanding of the psychosocial aspects of the school climate that can be leveraged for this purpose. The research reported in this article used structural equation modelling (with data from a sample of 6120 students at…

Structural Factors Influencing Menstruating School Girls' Health and Well-Being in Tanzania

ERIC Educational Resources Information Center

Sommer, Marni

2013-01-01

The importance of girls' education for population health outcomes in low-income countries is well documented. Despite this critical relationship, the global public health community has tended to overlook aspects of the school environment that may hinder girls' pubertal transitions in schools across low-income countries. Minimal empirical attention…

Design and construction principles in nature and architecture.

PubMed

Knippers, Jan; Speck, Thomas

2012-03-01

This paper will focus on how the emerging scientific discipline of biomimetics can bring new insights into the field of architecture. An analysis of both architectural and biological methodologies will show important aspects connecting these two. The foundation of this paper is a case study of convertible structures based on elastic plant movements.

Andrew Liehr and the structure of Jahn-Teller surfaces

NASA Astrophysics Data System (ADS)

Chibotaru, Liviu F.; Iwahara, Naoya

2017-05-01

The present article is an attempt to draw attention to a seminal work by Andrew Liehr “Topological aspects of conformational stability problem” [1, 2] issued more than half century ago. The importance of this work stems from two aspects of static Jahn-Teller and pseudo-Jahn-Teller problems fully developed by the author. First, the work of Liehr offers an almost complete overview of adiabatic potential energy surfaces for most known Jahn-Teller problems including linear, quadratic and higher-order vibronic couplings. Second, and most importantly, it identifies the factors defining the structure of Jahn-Teller surfaces. Among them, one should specially mention the minimax principle stating that the distorted Jahn-Teller systems tend to preserve the highest symmetry consistent with the loss of their orbital degeneracy. We believe that the present short reminiscence not only will introduce a key Jahn-Teller scientist to the young members of the community but also will serve as a vivid example of how a complete understanding of a complex problem, which the Jahn-Teller effect certainly was in the beginning of 1960s, can be achieved.

Geomorphic Implications of Fire and Slope Aspect in the Jemez Mountains, New Mexico, USA

NASA Astrophysics Data System (ADS)

Fitch, E. P.; Meyer, G. A.

2011-12-01

Following a fire, extensive erosion may occur on hillslopes due to reduced infiltration and increased runoff as well as a decrease in vegetative anchoring and surface roughness. This increased erosion and subsequent sedimentation on alluvial fans at the base of the hillslope may be the primary process of geomorphic change in fire-prone mountains in the Western US. Insolation differences on north and south facing slopes may also be another potential influence on geomorphic change due to soil moisture and vegetation differences, which may affect the spatial distribution of erosion as well as sediment transport processes. Due to the long recovery period of forest stands in fire-prone areas, it is important to understand the natural variability of erosion for the purposes of forest and river ecology and management as well as mass movement-flooding hazard. The 2002 Lakes Fire area in the Jemez Mountains, NM, provides a natural study area with incision of alluvial fans after the Lakes Fire exposing the internal structure of these fans. The study area displays steeper, drier ponderosa pine dominated south-facing slopes and less steep, moister Douglas-fir dominated north-facing slopes, which suggests that slope aspect may influence fire regime and post-fire erosion in the Jemez Mountains. In order to determine the importance of fire and aspect on erosion and sedimentation, over 15 sections within alluvial fans with both north and south aspect were studied. Debris flow, hyperconcentrated flow and stream flow make up the majority of sediment transport processes in this area. Therefore, deposits formed by these processes were described, and evidence for fire-related sedimentation was assessed. Additionally, the relative importance of sediment transport types in relation to north versus south slope aspects was examined. Finally, charcoal fragments within deposits from north and south aspects were analyzed in terms of their abundance and angularity in order to aid in estimating the severity of the fire event associated with the deposit. In this way, the importance of fire and aspect in influencing erosion and sediment transport was assessed for the study area.

Microdosimetry: Principles and applications

PubMed Central

Santa Cruz, Gustavo A.

2016-01-01

Aim to present the most important aspects of Microdosimetry, a research field in radiation biophysics. Background microdosimetry is the branch of radiation biophysics that systematically studies the spatial, temporal and spectral aspects of the stochastic nature of the energy deposition processes in microscopic structures. Materials and Methods we briefly review its history, the people, the formalism and the theories and devices that allowed researchers to begin to understand the true nature of radiation action on living matter. Results and Conclusions we outline some of its applications, especially to Boron Neutron Capture Therapy, attempting to explain the biological effectiveness of the boron thermal neutron capture reaction. PMID:26933397

Following the Social Media: Aspect Evolution of Online Discussion

NASA Astrophysics Data System (ADS)

Tang, Xuning; Yang, Christopher C.

Due to the advance of Internet and Web 2.0 technologies, it is easy to extract thousands of threads about a topic of interest from an online forum but it is nontrivial to capture the blueprint of different aspects (i.e., subtopic, or facet) associated with the topic. To better understand and analyze a forum discussion given topic, it is important to uncover the evolution relationships (temporal dependencies) between different topic aspects (i.e. how the discussion topic is evolving). Traditional Topic Detection and Tracking (TDT) techniques usually organize topics as a flat structure but it does not present the evolution relationships between topic aspects. In addition, the properties of short and sparse messages make the content-based TDT techniques difficult to perform well in identifying evolution relationships. The contributions in this paper are two-folded. We formally define a topic aspect evolution graph modeling framework and propose to utilize social network information, content similarity and temporal proximity to model evolution relationships between topic aspects. The experimental results showed that, by incorporating social network information, our technique significantly outperformed content-based technique in the task of extracting evolution relationships between topic aspects.

Ankle foot orthoses for people with Charcot Marie Tooth disease--views of users and orthotists on important aspects of use.

PubMed

Phillips, Margaret; Radford, Kathryn; Wills, Adrian

2011-01-01

To explore important aspects of the benefits, important characteristics, barriers to use and disadvantages of using ankle foot orthoses (AFOs) as seen by people with Charcot Marie Tooth disease (CMT) and the orthotists who will fit and supply them. This qualitative study used the nominal group technique and individual semi-structured interviews, according to participant preference and ability to travel. Propositions were put to 15 participants (eight females) with CMT regarding benefits, disadvantages, barriers to use and important characteristics of ankle foot orthoses AFOs and regarding benefits and disadvantages to seven orthotists. Priorities in these areas were ranked and a thematic analysis of the free text was made separately by two observers and a joint decision made of final themes. Fifteen people (eight females) with CMT and seven orthotists participated. Users' themes concerned functional mobility walking, pain/discomfort, choice of AFOs and associated footwear, custom made design, use in practical situations and support for foot and ankle. They noted that AFOs improved walking, but practical aspects of use and provision, as well as consideration of cosmetic aspects, were frequently problematic. Orthotists had similar themes, but with a difference in emphasis, that included prevention of future complications, education regarding device limitations and craftsmanship as a further theme. Users understood the potential benefits of AFOs and could identify disadvantages which might be remedied, but were frustrated by the difficulties in translating this into practice. Further refinement of current orthoses and delivery of orthotic services may assist in addressing these issues. © 2011 Informa UK, Ltd.

External and internal factors influencing self-directed online learning of physiotherapy undergraduate students in Sweden: a qualitative study.

PubMed

Hammarlund, Catharina Sjödahl; Nilsson, Maria H; Gummesson, Christina

2015-01-01

Online courses have become common in health sciences education. This learning environment can be designed using different approaches to support student learning. To further develop online environment, it is important to understand how students perceive working and learning online. The aim of this study is to identify aspects influencing students' learning processes and their adaptation to self-directed learning online. Thirty-four physiotherapy students with a mean age of 25 years (range, 21 to 34 years) participated. Qualitative content analysis and triangulation was used when investigating the students' self-reflections, written during a five week self-directed, problem-oriented online course. Two categories emerged: 'the influence of the structured framework' and 'communication and interaction with teachers and peers.' The learning processes were influenced by external factors, e.g., a clear structure including a transparent alignment of assignments and assessment. Important challenges to over-come were primarily internal factors, e.g., low self-efficacy, difficulties to plan the work effectively and adapting to a new environment. The analyses reflected important perspectives targeting areas which enable further course development. The influences of external and internal factors on learning strategies and self-efficacy are important aspects to consider when designing online courses. Factors such as pedagogical design, clarity of purpose, goals, and guidelines were important as well as continuous opportunities for communication and collaboration. Further studies are needed to understand and scaffold the motivational factors among students with low self-efficacy.

Protein-Protein Interface and Disease: Perspective from Biomolecular Networks.

PubMed

Hu, Guang; Xiao, Fei; Li, Yuqian; Li, Yuan; Vongsangnak, Wanwipa

Protein-protein interactions are involved in many important biological processes and molecular mechanisms of disease association. Structural studies of interfacial residues in protein complexes provide information on protein-protein interactions. Characterizing protein-protein interfaces, including binding sites and allosteric changes, thus pose an imminent challenge. With special focus on protein complexes, approaches based on network theory are proposed to meet this challenge. In this review we pay attention to protein-protein interfaces from the perspective of biomolecular networks and their roles in disease. We first describe the different roles of protein complexes in disease through several structural aspects of interfaces. We then discuss some recent advances in predicting hot spots and communication pathway analysis in terms of amino acid networks. Finally, we highlight possible future aspects of this area with respect to both methodology development and applications for disease treatment.

Review of ship slamming loads and responses

NASA Astrophysics Data System (ADS)

Wang, Shan; Guedes Soares, C.

2017-12-01

The paper presents an overview of studies of slamming on ship structures. This work focuses on the hull slamming, which is one of the most important types of slamming problems to be considered in the ship design process and the assessment of the ship safety. There are three main research aspects related to the hull slamming phenomenon, a) where and how often a slamming event occurs, b) slamming load prediction and c) structural response due to slamming loads. The approaches used in each aspect are reviewed and commented, together with the presentation of some typical results. The methodology, which combines the seakeeping analysis and slamming load prediction, is discussed for the global analysis of the hull slamming of a ship in waves. Some physical phenomena during the slamming event are discussed also. Recommendations for the future research and developments are made.

Facile fabrication of nanofluidic diode membranes using anodic aluminium oxide.

PubMed

Wu, Songmei; Wildhaber, Fabien; Vazquez-Mena, Oscar; Bertsch, Arnaud; Brugger, Juergen; Renaud, Philippe

2012-09-21

Active control of ion transport plays important roles in chemical and biological analytical processes. Nanofluidic systems hold the promise for such control through electrostatic interaction between ions and channel surfaces. Most existing experiments rely on planar geometry where the nanochannels are generally very long and shallow with large aspect ratios. Based on this configuration the concepts of nanofluidic gating and rectification have been successfully demonstrated. However, device minimization and throughput scaling remain significant challenges. We report here an innovative and facile realization of hetero-structured Al(2)O(3)/SiO(2) (Si) nanopore array membranes by using pattern transfer of self-organized nanopore structures of anodic aluminum oxide (AAO). Thanks to the opposite surface charge states of Al(2)O(3) (positive) and SiO(2) (negative), the membrane exhibits clear rectification of ion current in electrolyte solutions with very low aspect ratios compared to previous approaches. Our hetero-structured nanopore arrays provide a valuable platform for high throughput applications such as molecular separation, chemical processors and energy conversion.

Investigation of evolution-related aspects of bacterial rhodopsins

NASA Technical Reports Server (NTRS)

1994-01-01

We have investigated evolution-related aspects of bacterial rhodopsins, the unique retinal-based energy transducing systems of halophilic archae. The approach was to describe both structural and functional aspects: the structure by sequencing genes to explore which regions are conserved, and the function by comparing proton and chloride transport in the closely related systems, bacteriorhodopsin and halorhodopsin, respectively. In the latter, we have made a good start toward the ultimate goal of separating the attributes of the general principles of retinal-based ionic pumps from those of the specific ion specificities, by determining the thermodynamics of the internal steps of the protein-mediated active transport process, as well as some of the intraprotein ion-transfer steps. Our present emphasis is on continuing to acquire the tools for studying what distinguishes proton transport from chloride transport. We consider it important, therefore, that we have been able to provide firm mathematical grounds for the kinetics analyses which underlies these studies. Our molecular biological studies have received a great boost from the expression vector for the bop gene based on a halobacterial plasmid, that we recently developed.

Which Aspects of Professional Commitment Can Effectively Retain Nurses in the Nursing Profession?

PubMed

Chang, Hao-Yuan; Shyu, Yea-Ing Lotus; Wong, May-Kuen; Friesner, Daniel; Chu, Tsung-Lan; Teng, Ching-I

2015-09-01

This study examined which aspects of professional commitment can effectively retain nurses in the nursing profession. This study used a longitudinal design, simple random sampling, and two-wave data collection to survey and follow up a representative sample of 579 nurses for 1 year in a major medical center in northern Taiwan. Items measuring each aspect of professional commitment came from Meyer et al.'s scale. In the second wave, administrative data were culled to determine whether these nurses remain employed as nurses. Structural equation modeling is used to analyze the data. Analytical results indicate that continuance commitment predicts nurse retention in the nursing profession (path coefficient = 0.34, p < .01). Institutional efforts to improve continuance commitment (e.g., improved salary structures and enhanced professional development opportunities) likely retain nurses in the nursing profession. The findings of this study indicate the importance of continuance intention in retaining nurses. Nursing managers who face staff retention issues may consider making efforts to improve nurse salary and employer-sponsored benefits. © 2015 Sigma Theta Tau International.

Structural dynamics of the mitochondrial compartment.

PubMed

Thorsness, P E

1992-09-01

The metabolic activities of mitochondria have been extensively characterized. However, there is much less known about the morphogenic changes of the mitochondrial compartment during growth, development and aging of the cell and the consequences of those structural changes on cellular metabolism. There is a growing body of evidence for interactions of mitochondria with cytoskeletal components and changes of mitochondrial structure during development and in response to changing environmental conditions. Segregation and recombination of mitochondrial genomes are also processes dependent upon the dynamic nature of the mitochondrial compartment. These regulatory and structural aspects of mitochondrial compartment dynamics will play an important role in the analysis of mitochondrial function and pathology.

First-principles molecular dynamics simulation study on electrolytes for use in redox flow battery

NASA Astrophysics Data System (ADS)

Choe, Yoong-Kee; Tsuchida, Eiji; Tokuda, Kazuya; Ootsuka, Jun; Saito, Yoshihiro; Masuno, Atsunobu; Inoue, Hiroyuki

2017-11-01

Results of first-principles molecular dynamics simulations carried out to investigate structural aspects of electrolytes for use in a redox flow battery are reported. The electrolytes studied here are aqueous sulfuric acid solutions where its property is of importance for dissolving redox couples in redox flow battery. The simulation results indicate that structural features of the acid solutions depend on the concentration of sulfuric acid. Such dependency arises from increase of proton dissociation from sulfuric acid.

Algorithm to find distant repeats in a single protein sequence

PubMed Central

Banerjee, Nirjhar; Sarani, Rangarajan; Ranjani, Chellamuthu Vasuki; Sowmiya, Govindaraj; Michael, Daliah; Balakrishnan, Narayanasamy; Sekar, Kanagaraj

2008-01-01

Distant repeats in protein sequence play an important role in various aspects of protein analysis. A keen analysis of the distant repeats would enable to establish a firm relation of the repeats with respect to their function and three-dimensional structure during the evolutionary process. Further, it enlightens the diversity of duplication during the evolution. To this end, an algorithm has been developed to find all distant repeats in a protein sequence. The scores from Point Accepted Mutation (PAM) matrix has been deployed for the identification of amino acid substitutions while detecting the distant repeats. Due to the biological importance of distant repeats, the proposed algorithm will be of importance to structural biologists, molecular biologists, biochemists and researchers involved in phylogenetic and evolutionary studies. PMID:19052663

Vortex Interactions from a Finite Span Cylinder with a Laminar Boundary Layer for Varied Parameters

NASA Astrophysics Data System (ADS)

Gildersleeve, Samantha; Amitay, Michael

2017-11-01

Flow structures around a stationary, wall-mounted, finite-span cylindrical pin were investigated experimentally over a flat plate to explore the effects of varied aspect ratio and pin mean height with respect to the local boundary layer. Nine static pin configurations were tested where the pin's mean height to the local boundary layer thickness were 0.5, 1, and 1.5 for a range of aspect ratios between 0.125 and 1.125. The freestream velocity was fixed at 11 m/s, corresponding to ReD 2800, 5600, and 8400, respectively. Three-dimensional flowfields were reconstructed and analyzed from SPIV measurements where data were collected along cross-stream planes in the wake of the pin. This study focuses on three dominant vortical patterns associated with a finite span cylinder: the arch-type vortex horseshoe vortex, and the tip vortices Results indicate that both the aspect ratio and mean height play an important role in the behavior and interactions of these vortex structures which alter the wake characteristics significantly. Understanding the mechanisms by which the vortical structures may be strengthened while reducing adverse local pressure drag are key for developing more efficient means of passive and/or active flow control through finite span cylindrical pins and will be discussed in further detail. NDSEG Fellowship for Samantha Gildersleeve.

Evaluation of Structure, Chaperone-Like Activity and Allergenicity of Reduced Glycated Adduct of Bovine β-casein.

PubMed

Yousefi, Reza; Ferdowsi, Leila; Tavaf, Zohreh; Sadeghian, Tanaz; Tamaddon, Ali M; Moghtaderi, Mozhgan; Pourpak, Zahra

2017-01-01

Milk has a potent reducing environment with an important quantity of sugar levels. In the current study β-casein was glycated in the presence of D-glucose and sodium cyanoborohydride as a reducing agent. Then, the reduced glucitol adduct of β-casein was used for the structural and functional analyses using different spectroscopic techniques. The results of fluorescence and far ultraviolet circular dichroism assessments suggest important structural alteration upon non-enzymatic glycation of β-casein. In addition, the chaperone activity, micellization properties and antioxidant activity of this protein were altered upon glucose modification. Also, as a result of reduced glycation, the allergenicity profile of this protein remained largely unchanged. Additional to its energetic and nutritional values, β-casein has important functional properties. The native structure of this protein is important to perform accurately its biological functions. Non-enzymatic glycation under reducing state was capable to alter both structural and functional aspects of β-casein. Due to effective reducing environment and significant quantity of reducing sugar of human milk, similar structural and functional alterations are most likely to occur upon reducing glycation of β-casein in vivo. Also, these changes might be even intensified during chronic hyperglycemia in diabetic mothers. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

The power of social networks and social support in promotion of physical activity and body mass index among African American adults.

PubMed

Flórez, Karen R; Richardson, Andrea S; Ghosh-Dastidar, Madhumita Bonnie; Troxel, Wendy; DeSantis, Amy; Colabianchi, Natalie; Dubowitz, Tamara

2018-04-01

Social support and social networks can elucidate important structural and functional aspects of social relationships that are associated with health-promoting behaviors, including Physical Activity (PA) and weight. A growing number of studies have investigated the relationship between social support, social networks, PA and obesity specifically among African Americans; however, the evidence is mixed and many studies focus exclusively on African American women. Most studies have also focused on either functional or structural aspects of social relationships (but not both) and few have objectively measured moderate-to-vigorous physical activity (MVPA) and body mass index (BMI). Cross-sectional surveys of adult African American men and women living in two low-income predominantly African American neighborhoods in Pittsburgh, PA (N = 799) measured numerous structural features as well as functional aspects of social relationships. Specifically, structural features included social isolation, and social network size and diversity. Functional aspects included perceptions of social support for physical activity from the social network in general as well as from family and friends specifically. Height, weight, and PA were objectively measured. From these, we derived Body Mass Index (BMI) and moderate-to-vigorous physical activity (MVPA). All regression models were stratified by gender, and included age, income, education, employment, marital status, physical limitations, and a neighborhood indicator. Greater social isolation was a significant predictor of lower BMI among men only. Among women only, social isolation was significantly associated with increased MVPA whereas, network diversity was significantly associated with reduced MVPA. Future research would benefit from in-depth qualitative investigations to understand how social networks may act to influence different types of physical activity among African Americans, as well as understand how they can be possible levers for health promotion and prevention.

Design, Fabrication and Test of Composite Curved Frames for Helicopter Fuselage Structure

NASA Technical Reports Server (NTRS)

Lowry, D. W.; Krebs, N. E.; Dobyns, A. L.

1984-01-01

Aspects of curved beam effects and their importance in designing composite frame structures are discussed. The curved beam effect induces radial flange loadings which in turn causes flange curling. This curling increases the axial flange stresses and induces transverse bending. These effects are more important in composite structures due to their general inability to redistribute stresses by general yielding, such as in metal structures. A detailed finite element analysis was conducted and used in the design of composite curved frame specimens. Five specimens were statically tested and compared with predicted and test strains. The curved frame effects must be accurately accounted for to avoid premature fracture; finite element methods can accurately predict most of the stresses and no elastic relief from curved beam effects occurred in the composite frames tested. Finite element studies are presented for comparative curved beam effects on composite and metal frames.

Aggregation and folding phase transitions of RNA molecules

NASA Astrophysics Data System (ADS)

Bundschuh, Ralf

2007-03-01

RNA is a biomolecule that is involved in nearly all aspects of cellular functions. In order to perform many of these functions, RNA molecules have to fold into specific secondary structures. This folding is driven by the tendency of the bases to form Watson-Crick base pairs. Beyond the biological importance of RNA, the relatively simple rules for structure formation of RNA make it a very interesting system from the statistical physics point of view. We will present examples of phase transitions in RNA secondary structure formation that are amenable to analytical descriptions. A special focus will be on aggregation between several RNA molecules which is important for some regulatory circuits based on RNA structure, triplet repeat diseases like Huntington's, and as a model for prion diseases. We show that depending on the relative strength of the intramolecular and the intermolecular base pairing, RNA molecules undergo a transition into an aggregated phase and quantitatively characterize this transition.

Langley's CSI evolutionary model: Phase 2

NASA Technical Reports Server (NTRS)

Horta, Lucas G.; Reaves, Mercedes C.; Elliott, Kenny B.; Belvin, W. Keith; Teter, John E.

1995-01-01

Phase 2 testbed is part of a sequence of laboratory models, developed at NASA Langley Research Center, to enhance our understanding on how to model, control, and design structures for space applications. A key problem with structures that must perform in space is the appearance of unwanted vibrations during operations. Instruments, design independently by different scientists, must share the same vehicle causing them to interact with each other. Once in space, these problems are difficult to correct and therefore, prediction via analysis design, and experiments is very important. Phase 2 laboratory model and its predecessors are designed to fill a gap between theory and practice and to aid in understanding important aspects in modeling, sensor and actuator technology, ground testing techniques, and control design issues. This document provides detailed information on the truss structure and its main components, control computer architecture, and structural models generated along with corresponding experimental results.

Patient safety priorities in mental healthcare in Switzerland: a modified Delphi study.

PubMed

Mascherek, Anna C; Schwappach, David L B

2016-08-05

Identifying patient safety priorities in mental healthcare is an emerging issue. A variety of aspects of patient safety in medical care apply for patient safety in mental care as well. However, specific aspects may be different as a consequence of special characteristics of patients, setting and treatment. The aim of the present study was to combine knowledge from the field and research and bundle existing initiatives and projects to define patient safety priorities in mental healthcare in Switzerland. The present study draws on national expert panels, namely, round-table discussion and modified Delphi consensus method. As preparation for the modified Delphi questionnaire, two round-table discussions and one semistructured questionnaire were conducted. Preparative work was conducted between May 2015 and October 2015. The modified Delphi was conducted to gauge experts' opinion on priorities in patient safety in mental healthcare in Switzerland. In two independent rating rounds, experts made private ratings. The modified Delphi was conducted in winter 2015. Nine topics were defined along the treatment pathway: diagnostic errors, non-drug treatment errors, medication errors, errors related to coercive measures, errors related to aggression management against self and others, errors in treatment of suicidal patients, communication errors, errors at interfaces of care and structural errors. Patient safety is considered as an important topic of quality in mental healthcare among experts, but it has been seriously neglected up until now. Activities in research and in practice are needed. Structural errors and diagnostics were given highest priority. From the topics identified, some are overlapping with important aspects of patient safety in medical care; however, some core aspects are unique. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Patient safety priorities in mental healthcare in Switzerland: a modified Delphi study

PubMed Central

Mascherek, Anna C

2016-01-01

Objective Identifying patient safety priorities in mental healthcare is an emerging issue. A variety of aspects of patient safety in medical care apply for patient safety in mental care as well. However, specific aspects may be different as a consequence of special characteristics of patients, setting and treatment. The aim of the present study was to combine knowledge from the field and research and bundle existing initiatives and projects to define patient safety priorities in mental healthcare in Switzerland. The present study draws on national expert panels, namely, round-table discussion and modified Delphi consensus method. Design As preparation for the modified Delphi questionnaire, two round-table discussions and one semistructured questionnaire were conducted. Preparative work was conducted between May 2015 and October 2015. The modified Delphi was conducted to gauge experts' opinion on priorities in patient safety in mental healthcare in Switzerland. In two independent rating rounds, experts made private ratings. The modified Delphi was conducted in winter 2015. Results Nine topics were defined along the treatment pathway: diagnostic errors, non-drug treatment errors, medication errors, errors related to coercive measures, errors related to aggression management against self and others, errors in treatment of suicidal patients, communication errors, errors at interfaces of care and structural errors. Conclusions Patient safety is considered as an important topic of quality in mental healthcare among experts, but it has been seriously neglected up until now. Activities in research and in practice are needed. Structural errors and diagnostics were given highest priority. From the topics identified, some are overlapping with important aspects of patient safety in medical care; however, some core aspects are unique. PMID:27496233

Thick-film acoustic emission sensors for use in structurally integrated condition-monitoring applications.

PubMed

Pickwell, Andrew J; Dorey, Robert A; Mba, David

2011-09-01

Monitoring the condition of complex engineering structures is an important aspect of modern engineering, eliminating unnecessary work and enabling planned maintenance, preventing failure. Acoustic emissions (AE) testing is one method of implementing continuous nondestructive structural health monitoring. A novel thick-film (17.6 μm) AE sensor is presented. Lead zirconate titanate thick films were fabricated using a powder/sol composite ink deposition technique and mechanically patterned to form a discrete thick-film piezoelectric AE sensor. The thick-film sensor was benchmarked against a commercial AE device and was found to exhibit comparable responses to simulated acoustic emissions.

Organizational Factors that Affect the Implementation of Information Technology: Perspectives of Middle Managers in Iran.

PubMed

Barzekar, Hosein; Karami, Mahtab

2014-10-01

to examine the organizational factors affecting the application of information technology in hospitals. Since the organizational factors are one of the most important determinants of successful projects, by understanding their impact and identifying them it can help planning a systematic IT implementation. In this cross-sectional descriptive study 110 middle managers were chosen from teaching hospitals. Structured questionnaire was used for the data collection. There was a significant relationship between organization resource, organizational knowledge, process, management structure and values and goals with implementation of information technology. Findings showed that organizational factors had a considerable impact on implementation of information technology. Top managers must consider the important aspects of effective organizational factors.

Children's Ideas about the Internal Structure of Trees: Cross-Age Studies

ERIC Educational Resources Information Center

Rybska, Eliza; Tunnicliffe, Sue Dale; Sajkowska, Zofia Anna

2017-01-01

Trees are important to the environment owing to their ecological services. However, many aspects of their form and function are poorly understood by the public. From their earliest years, children have an elementary knowledge about plants which they gain from their everyday observations, their parents and other people and from their kindergarten…

Dynamics of fire plumes in verticle shear

Treesearch

Philip Cunningham; Scott L. Goodrick; Hussaini M. Yousuff; Rodman R. Linn; Chunmei Xia

2003-01-01

Plumes from wildfires and prescribed fires represent a critical aspect of smoke mangement and aire quality assessment, as as such it is important to understand the structure and dynamics of these plumes, both with respect to a basic understanding of the phenomena and with respect to an assessment of the validity of plumerise parameterizations over a wide variety of...

Cooperative Learning: Homogeneous and Heterogeneous Grouping of Iranian EFL Learners in a Writing Context

ERIC Educational Resources Information Center

Zamani, Mona

2016-01-01

One of the important aspects of learning and teaching through cooperation is the group composition or grouping "who with whom". An unresolved issue is that of the superiority of heterogeneity or homogeneity in the structure of the groups. The present study was an attempt to investigate the impact that homogeneous and heterogeneous…

A Multidimensional Screening Tool for Preschoolers with Externalizing Behavior: Factor Structure and Factorial Invariance

ERIC Educational Resources Information Center

Vancraeyveldt, Caroline; Verschueren, Karine; Wouters, Sofie; Van Craeyevelt, Sanne; Colpin, Hilde

2014-01-01

Externalizing behavior (EB) in preschool has been found to predict maladjustment later in life. Therefore, it is important to identify children most at risk for continuing EB beyond preschool. To date, a number of questionnaires are available for teachers to assist in identifying those children. A frequently overlooked aspect in this screening…

Production of Accurate Skeletal Models of Domestic Animals Using Three-Dimensional Scanning and Printing Technology

ERIC Educational Resources Information Center

Li, Fangzheng; Liu, Chunying; Song, Xuexiong; Huan, Yanjun; Gao, Shansong; Jiang, Zhongling

2018-01-01

Access to adequate anatomical specimens can be an important aspect in learning the anatomy of domestic animals. In this study, the authors utilized a structured light scanner and fused deposition modeling (FDM) printer to produce highly accurate animal skeletal models. First, various components of the bovine skeleton, including the femur, the…

Exploring a Structure for Mathematics Lessons That Foster Problem Solving and Reasoning

ERIC Educational Resources Information Center

Sullivan, Peter; Walker, Nadia; Borcek, Chris; Rennie, Mick

2015-01-01

While there is widespread agreement on the importance of incorporating problem solving and reasoning into mathematics classrooms, there is limited specific advice on how this can best happen. This is a report of an aspect of a project that is examining the opportunities and constraints in initiating learning by posing challenging mathematics tasks…

Identification of Colors for Building.

ERIC Educational Resources Information Center

Building Research Inst., Inc., Washington, DC.

A demonstration of how colors may be specified for use by all those trades and professions involved in building science. This is of vital importance in furthering the use of color, not only in structures but in every other aspect of our daily usage. Free enterprise requires a color language in order to expand the use of color, and to allow for…

Examining the Use of a Structured Analysis Framework to Support Prospective Teacher Noticing

ERIC Educational Resources Information Center

Mitchell, Rebecca N.; Marin, Katherine Ariemma

2015-01-01

The ability to notice important events in a teaching situation and make decisions about these events is a key component of teaching well. Prospective teachers tend to notice more superficial aspects of classroom practice, such as class management. This article examines a video club in which four student teachers utilized the Mathematical Quality…

Authoritative School Discipline: High School Practices Associated with Lower Bullying and Victimization

ERIC Educational Resources Information Center

Gregory, Anne; Cornell, Dewey; Fan, Xitao; Sheras, Peter; Shih, Tse-Hua; Huang, Francis

2010-01-01

In this study we examined authoritative discipline theory, which posits that 2 complementary aspects of school climate--structure and support--are important for adolescents' safety in school. Using a statewide sample of over 7,300 ninth-grade students and 2,900 teachers randomly selected from 290 high schools, we showed, using hierarchical linear…

Extending the Theoretical Framing for Physics Education Research: An Illustrative Application of Complexity Science

ERIC Educational Resources Information Center

Forsman, Jonas; Moll, Rachel; Linder, Cedric

2014-01-01

The viability of using complexity science in physics education research (PER) is exemplified by (1) situating central tenets of student persistence research in complexity science and (2) drawing on the methods that become available from this to illustrate analyzing the structural aspects of students' networked interactions as an important dynamic…

Structure and regional differences in U.S. Blumeria graminis f. sp. tritici populations: divergence, migration, fungicide sensitivity, and virulence patterns

USDA-ARS?s Scientific Manuscript database

Several aspects of the biology of USA populations of wheat powdery mildew (Blumeria graminis f. sp. tritici, or Bgt) have been investigated for their importance to the integrated management of this widespread and potentially damaging pathogen. For example, the virulence profiles of U.S. Bgt populat...

"Blame" Concept in Phraseology: Cognitive-Semantic Aspect (Based on the French Language)

ERIC Educational Resources Information Center

Zalavina, Tatyana Y.; Kisel, Olesya V.

2016-01-01

Phraseology is one of the basic and most important objects of study in cognitive linguistics. The article deals with verbal fixed phrases in their correlation with the cognitive structure of knowledge--a concept. The used definitional analysis method to identify the basic notions of the conceptual content of the concept of blame and basic…

Innovative Language-Based & Object-Oriented Structured AMR Using Fortran 90 and OpenMP

NASA Technical Reports Server (NTRS)

Norton, C.; Balsara, D.

1999-01-01

Parallel adaptive mesh refinement (AMR) is an important numerical technique that leads to the efficient solution of many physical and engineering problems. In this paper, we describe how AMR programing can be performed in an object-oreinted way using the modern aspects of Fortran 90 combined with the parallelization features of OpenMP.

Encouraging Cognitive Connections and Creativity in the Music Classroom

ERIC Educational Resources Information Center

Peterson, Christopher W.; Madsen, Clifford K.

2010-01-01

The ability to apply knowledge rests at the core of the educational experience and is an important aspect of all teaching. In music education, many experiences are structured so information gained can be related to another activity, but such transfer can be difficult. When students learn to transfer information and knowledge to new situations,…

Structural and functional measures of social relationships and quality of life among older adults: does chronic disease status matter?

PubMed

Liao, Jing; Brunner, Eric J

2016-01-01

To evaluate the relative importance of structural and functional social relationships for quality of life (QoL) and the extent to which diagnosed chronic disease modifies these associations. Multivariate linear regression was used to investigate time-lagged associations between structural and functional measures of social relationships and QoL assessed 5 years apart by CASP-19, in 5925 Whitehall II participants (mean age 61, SD 6.0). Chronic disease was clinically verified coronary heart disease, stroke, diabetes or cancer. Social relationships-QoL associations were consistent across disease status (P-values for interaction: 0.15-0.99). Larger friend network (β = 1.9, 95% CI 1.5-2.3), having a partner (β = 1.2, 95% CI 0.5-1.7), higher confiding support (β = 2.2, 95% CI 1.8-2.7) and lower negative aspects of close relationships (β = 3.3, 95% CI 2.8-3.8) were independently related to improved QoL in old age. The estimated difference in QoL due to social relationships was equivalent to up to 0.5 SD of the CASP-19 score and was stronger than the effect of chronic disease (coronary heart disease β = 2.0, 95% CI 1.4-2.6). We found that beneficial aspects of social relationships in relation to QoL were, in order of importance: avoiding negative aspects of close relationships, having confiding support, having a wide network of friends and having a partner. These associations were not modified by chronic disease. Thus, despite inevitable physical deterioration, we may be able to enhance a satisfying late life by optimizing our social relationships.

Evaluation of individual quality of life among hemodialysis patients: nominated themes using SEIQoL-adapted.

PubMed

Matlabi, Hossein; Ahmadzadeh, Sharareh

2017-01-01

Quality of life (QoL) has become an important issue for patients with chronic renal failure diseases who are permanently undergoing hemodialysis. In this study, an adapted schedule for the evaluation of individual quality of life (SEIQoL-adapted) was used to evaluate QoL among hemodialysis patients, to explore their views about the most important aspects of life satisfaction. A multiple approach design and convenience sampling were applied to recruit 53 patients from a hemodialysis unit in Iran. Data were collected through structured interviews and then analyzed using conventional content analysis. A total score for QoL was calculated using scale guideline. The most important aspects of life were health, family, financial status, living conditions, leisure activities, relationships and socializing, religious and spiritual issues, medical knowledge, and therapies or treatments. The calculated mean QoL score was 66.2, indicating a relatively high life satisfaction. Males had higher QoL scores than females in both married and single groups. Moreover, the relationships between the QoL scores and education, job and marital status were not statistically significant. The SEIQoL-adapted revealed reasonable lay definitions of QoL in a group of patients following chronic renal failure. The patients' views of the aspects of life could be used by health policy makers, clinicians, and caregivers as a reliable guide to the most important priorities for treatment and medical interventions.

Towards improved NDE and SHM methodologies incorporating nonlinear structural features

NASA Astrophysics Data System (ADS)

Chillara, Vamshi Krishna

Ultrasound is widely employed in Nondestructive Evaluation (NDE) and Structural Health Monitoring (SHM) applications to detect and characterize damage/defects in materials. In particular, ultrasonic guided waves are considered a foremost candidate for in-situ monitoring applications. Conventional ultrasonic techniques rely on changes/discontinuities in linear elastic material properties, namely the Young's modulus and shear modulus to detect damage. On the other hand, nonlinear ultrasonic techniques that rely on micro-scale nonlinear material/structural behavior are proven to be sensitive to damage induced microstructural changes that precede macro-scale damage and are hence capable of early damage detection. The goal of this thesis is to investigate the capabilities of nonlinear guided waves --- a fusion of nonlinear ultrasonic techniques with the guided wave methodologies for early damage detection. To that end, the thesis focuses on two important aspects of the problem: 1. Wavemechanics - deals with ultrasonic guided wave propagation in nonlinear waveguides; 2. Micromechanics - deals with correlating ultrasonic response with micro-scale nonlinear material behavior. For the development of efficient NDE and SHM methodologies that incorporate nonlinear structural features, a detailed understanding of the above aspects is indispensable. In this thesis, the wavemechanics aspect of the problem is dealt with from both theoretical and numerical standpoints. A generalized theoretical framework is developed to study higher harmonic guided waves in plates. This was employed to study second harmonic guided waves in pipes using a large-radius asymptotic approximation. Second harmonic guided waves in plates are studied from a numerical standpoint. Theoretical predictions are validated and some key aspects of higher harmonic generation in waveguides are outlined. Finally, second harmonic guided waves in plates with inhomogeneous and localized nonlinearities are studied and some important aspects of guided wave mode selection are addressed. The other part of the work focused on developing a micromechanics based understanding of ultrasonic higher harmonic generation. Three important aspects of micro-scale material behavior, namely tension-compression asymmetry, shearnormal coupling and deformation induced asymmetry are identified and their role in ultrasonic higher harmonic generation is discussed. Tension-compression asymmetry is identified to cause second (even) harmonic generation in materials. Then, shearnormal coupling is identified to cause generation of secondary waves of different polarity than the primary waves. In addition, deformation induced anisotropy due to the presence of residual stress/strain and its contribution to ultrasonic higher harmonic generation is qualitatively discussed. Also, the tension-compression asymmetry in the material is quantified using an energy based measure. The above measure is employed to develop a homogenization based approach amenable to multi-scale analysis to correlate microstructure with ultrasonic higher harmonic generation. Finally, experimental investigations concerning third harmonic SH wave generation in plates are carried out and the effect of load and temperature changes on nonlinear ultrasonic measurements are discussed in the context of SHM. It was found that while nonlinear ultrasound is sensitive to micro-scale damage, the relative nonlinearity parameter may not always be the best measure to quantify the nonlinearity as it is subject to spurious effects from changes in environmental factors such as loads and temperature.

Aging and social networks in Spain: the importance of pubs and churches.

PubMed

Buz, José; Sanchez, Marta; Levenson, Michael R; Aldwin, Carolyn M

2014-01-01

We examined whether the social convoy model and socioemotional selectivity theory apply in collectivistic cultures by examining the contextual factors which are hypothesized to mediate age-related differences in social support in a collectivist European country. Five hundred Spanish community-dwelling older adults (Mean age = 74.78, SD = 7.76, range = 60-93) were interviewed to examine structural aspects of their social networks. We found that age showed highly complex relationships with network size and frequency of interaction, depending on the network circle and the mediation of cultural factors. Family structure was important for social relations in the inner circle, while pubs and churches were important for peripheral relations. Surprisingly, pub attendance was the most important variable for maintenance of social support of peripheral network members. In general, the results support the applicability of the social convoy and socioemotional selectivity constructs to social support among Spanish older adults.

The Impact of Climate Change on the United States Economy

NASA Astrophysics Data System (ADS)

Mendelsohn, Robert; Neumann, James E.

2004-08-01

Understanding the impacts of climate change on economic behaviour is an important aspect of deciding when to take policy actions to prevent or mitigate its consequences. This book applies advanced new economics methodologies to assess impacts on potentially vulnerable aspects of the US economy: agriculture, timber, coastal resources, energy expenditure, fishing, outdoor recreation. It is intended to provide improved understanding of key issues raised in the recent Intergovernmental Panel on Climate Change (IPCC) reports. It concludes that some climate change may produce economic gains in the agriculture and forestry sectors, whereas energy, coastal structures, and water sectors may be harmed. The book will serve as an important reference for the scientific, economic, and policy community, and will also be of interest to natural resource/environmental economists as an example of economic valuation techniques. The volume will clearly be of main importance to researchers and policymakers in the US, but will also be influential as a model for assessment of impacts on economies worldwide.

Multiple aspects of high school students' strategic processing on reading outcomes: The role of quantity, quality, and conjunctive strategy use.

PubMed

Parkinson, Meghan M; Dinsmore, Daniel L

2018-03-01

While the literature on strategy use is relatively mature, measures of strategy use overwhelmingly measure only one aspect of that use, frequency, when relating that strategy use to performance outcomes. While this might be one important attribute of strategy use, there is increasing evidence that quality and conditional use of cognitive and metacognitive strategies may also be important. This study examines how multiple aspects of strategy use, namely frequency, quality, and conjunctive use of strategies, influence task performance on both well- and ill-structured task outcomes in addition to other concomitant variables that may interact with strategic processing during reading. The sample consisted of 21 high school students enrolled in an upper-level biology class in a suburban school in the north-eastern United States. These participants completed measures of prior knowledge and interest, then read either an expository or persuasive text while thinking aloud. They then completed a passage recall and open-ended response following passage completion. In general, quantity was not positively related to the study outcomes and was negatively related to one of them. Quality of strategy use, on the other hand, was consistently related to positive reading outcomes. The influence of knowledge and interest in terms of strategies is also discussed as well as six cases which illustrate the relation of aspects of strategy use and the other concomitant variables. Evaluating strategy use by solely examining the frequency of strategy use did not explain differences in task performance as well as evaluating the quality and conjunctive use of strategies. Further, important relations between prior knowledge, interest, and the task outcomes appeared to be mediated and moderated by the aspects of strategy use investigated. © 2017 The British Psychological Society.

Promoting cognitive and social aspects of inquiry through classroom discourse

NASA Astrophysics Data System (ADS)

Jin, Hui; Wei, Xin; Duan, Peiran; Guo, Yuying; Wang, Wenxia

2016-01-01

We investigated how Chinese physics teachers structured classroom discourse to support the cognitive and social aspects of inquiry-based science learning. Regarding the cognitive aspect, we examined to what extent the cognitive processes underlying the scientific skills and the disciplinary reasoning behind the content knowledge were taught. Regarding the social aspect, we examined how classroom discourse supported student learning in terms of students' opportunities to talk and interaction patterns. Our participants were 17 physics teachers who were actively engaged in teacher education programs in universities and professional development programs in local school districts. We analyzed one lesson video from each participating teacher. The results suggest both promises and challenges. Regarding the cognitive aspect of inquiry, the teachers in general recognized the importance of teaching the cognitive processes and disciplinary reasoning. However, they were less likely to address common intuitive ideas about science concepts and principles. Regarding the social aspect of inquiry, the teachers frequently interacted with students in class. However, it appeared that facilitating conversations among students and prompting students to talk about their own ideas are challenging. We discuss the implications of these findings for teacher education programs and professional development programs in China.

Organization structure as a moderator of the relationship between procedural justice, interactional justice, perceived organizational support, and supervisory trust.

PubMed

Ambrose, Maureen L; Schminke, Marshall

2003-04-01

Organizational justice researchers recognize the important role organization context plays in justice perceptions, yet few studies systematically examine contextual variables. This article examines how 1 aspect of context--organizational structure--affects the relationship between justice perceptions and 2 types of social exchange relationships, organizational and supervisory. The authors suggest that under different structural conditions, procedural and interactional justice will play differentially important roles in determining the quality of organizational social exchange (as evidenced by perceived organizational support [POS]) and supervisory social exchange (as evidenced by supervisory trust). In particular, the authors hypothesized that the relationship between procedural justice and POS would be stronger in mechanistic organizations and that the relationship between interactional justice and supervisory trust would be stronger in organic organizations. The authors' results support these hypotheses.

Impact of erosion testing aspects on current and future flight conditions

NASA Astrophysics Data System (ADS)

Gohardani, Omid

2011-05-01

High speed of aero vehicles including commercial and military aircraft, missiles, unmanned air vehicles, as well as conceptual aircraft of the future are imposing larger restrictions on the materials of these vehicles and highlight the importance of adequate quantification of material behavior and performance during different flight conditions. Erosion due to weather conditions and other present particles such as hydrometeors; rain, hail and ice, as well as sand, volcanic ash and dust resulting from residues in the atmosphere are eminent as hazardous on the structure of a flying vehicle and may adversely influence the lifecycle of the structure. This study outlines an extensive review of research efforts on erosion in aviation and provides a basis for comparison between different apparatus simulating rain erosion and their usage within the aerospace industry. The significant aspects of erosion testing and future prospects for erosion impact are further addressed for forthcoming generations of flying vehicles.

Factor structure of the Japanese Interpersonal Competence Scale.

PubMed

Matsudaira, Tomomi; Fukuhara, Taihei; Kitamura, Toshinori

2008-04-01

Assessing social competence is important for clinical and preventive interventions of depression. The aim of the present paper was to examine the factor structure of the Japanese Interpersonal Competence Scale (JICS). Exploratory and confirmatory factor analysis was performed on the survey responses of 730 participants. Simultaneous multigroup analyses were conducted to confirm factor stability across psychological health status and sex differences. Two factors, which represent Perceptive Ability and Self-Restraint, were confirmed to show a moderate correlation. Perceptive Ability involves a more cognitive aspect of social competence, while Self-Restraint involves a more behavioral aspect, both of which are considered to reflect the emotion-based relating style specific to the Japanese people: indulgent dependence (amae) and harmony (wa). In addition, Self-Restraint may be linked to social functioning. Both constructs may confound a respondent's perceived confidence. Despite its shortcomings, the JICS is a unique measure of social competence in the Japanese cultural context.

Aspects concerning verification methods and rigidity increment of complex technological systems

NASA Astrophysics Data System (ADS)

Casian, M.

2016-11-01

Any technological process and technology aims a quality and precise product, something almost impossible without high rigidity machine tools, equipment and components. Therefore, from the design phase, it is very important to create structures and machines with high stiffness characteristics. At the same time, increasing the stiffness should not raise the material costs. Searching this midpoint between high rigidity and minimum expenses leads to investigations and checks in structural components through various methods and techniques and sometimes quite advanced methods. In order to highlight some aspects concerning the significance of the mechanical equipment rigidity, the finite element method and an analytical method based on the use Mathcad software were used, by taking into consideration a subassembly of a grinding machine. Graphical representations were elaborated, offering a more complete image about the stresses and deformations able to affect the considered mechanical subassembly.

Optimal Control Allocation with Load Sensor Feedback for Active Load Suppression, Flight-Test Performance

NASA Technical Reports Server (NTRS)

Miller, Christopher J.; Goodrick, Dan

2017-01-01

The problem of control command and maneuver induced structural loads is an important aspect of any control system design. The aircraft structure and the control architecture must be designed to achieve desired piloted control responses while limiting the imparted structural loads. The classical approach is to utilize high structural margins, restrict control surface commands to a limited set of analyzed combinations, and train pilots to follow procedural maneuvering limitations. With recent advances in structural sensing and the continued desire to improve safety and vehicle fuel efficiency, it is both possible and desirable to develop control architectures that enable lighter vehicle weights while maintaining and improving protection against structural damage. An optimal control technique has been explored and shown to achieve desirable vehicle control performance while limiting sensed structural loads to specified values. This technique has been implemented and flown on the National Aeronautics and Space Administration Full-scale Advanced Systems Testbed aircraft. The flight tests illustrate that the approach achieves the desired performance and show promising potential benefits. The flights also uncovered some important issues that will need to be addressed for production application.

Trade-off between Photon Management Efficacy and Material Quality in Thin-Film Solar Cells on Nanostructured Substrates of High Aspect Ratio Structures

DOE PAGES

Chin, Alan; Keshavarz, Majid; Wang, Qi

2018-04-13

Although texturing of the transparent electrode of thin-film solar cells has long been used to enhance light absorption via light trapping, such texturing has involved low aspect ratio features. With the recent development of nanotechnology, nanostructured substrates enable improved light trapping and enhanced optical absorption via resonances, a process known as photon management, in thin-film solar cells. Despite the progress made in the development of photon management in thin-film solar cells using nanostructures substrates, the structural integrity of the thin-film solar cells deposited onto such nanostructured substrates is rarely considered. Here, we report the observation of the reduction in themore » open circuit voltage of amorphous silicon solar cells deposited onto a nanostructured substrate with increasing areal number density of high aspect ratio structures. For a nanostructured substrate with the areal number density of such nanostructures increasing in correlation with the distance from one edge of the substrate, a correlation between the open circuit voltage reduction and the increase of the areal number density of high aspect ratio nanostructures of the front electrode of the small-size amorphous silicon solar cells deposited onto different regions of the substrate with graded nanostructure density indicates the effect of the surface morphology on the material quality, i.e., a trade-off between photon management efficacy and material quality. Lastly, this observed trade-off highlights the importance of optimizing the morphology of the nanostructured substrate to ensure conformal deposition of the thin-film solar cell.« less

Trade-off between Photon Management Efficacy and Material Quality in Thin-Film Solar Cells on Nanostructured Substrates of High Aspect Ratio Structures

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

Chin, Alan; Keshavarz, Majid; Wang, Qi

Although texturing of the transparent electrode of thin-film solar cells has long been used to enhance light absorption via light trapping, such texturing has involved low aspect ratio features. With the recent development of nanotechnology, nanostructured substrates enable improved light trapping and enhanced optical absorption via resonances, a process known as photon management, in thin-film solar cells. Despite the progress made in the development of photon management in thin-film solar cells using nanostructures substrates, the structural integrity of the thin-film solar cells deposited onto such nanostructured substrates is rarely considered. Here, we report the observation of the reduction in themore » open circuit voltage of amorphous silicon solar cells deposited onto a nanostructured substrate with increasing areal number density of high aspect ratio structures. For a nanostructured substrate with the areal number density of such nanostructures increasing in correlation with the distance from one edge of the substrate, a correlation between the open circuit voltage reduction and the increase of the areal number density of high aspect ratio nanostructures of the front electrode of the small-size amorphous silicon solar cells deposited onto different regions of the substrate with graded nanostructure density indicates the effect of the surface morphology on the material quality, i.e., a trade-off between photon management efficacy and material quality. Lastly, this observed trade-off highlights the importance of optimizing the morphology of the nanostructured substrate to ensure conformal deposition of the thin-film solar cell.« less

Importance of Adequate Gross Anatomy Education: The Impact of a Structured Pelvic Anatomy Course during Gynecology Fellowship

ERIC Educational Resources Information Center

Heisler, Christine Aminda

2011-01-01

Medical education underwent standardization at the turn of the 20th century and remained fairly consistent until recently. Incorporation of a patient-centered or case-based curriculum is believed to reinforce basic science concepts. One negative aspect is a reduction in hours spent with cadaveric dissection in the gross anatomy laboratory. For…

Event Schemas in Autism Spectrum Disorders: The Role of Theory of Mind and Weak Central Coherence

ERIC Educational Resources Information Center

Loth, Eva; Gomez, Juan Carlos; Happe, Francesca

2008-01-01

Event schemas (generalized knowledge of what happens at common real-life events, e.g., a birthday party) are an important cognitive tool for social understanding: They provide structure for social experiences while accounting for many variable aspects. Using an event narratives task, this study tested the hypotheses that theory of mind (ToM)…

There Is More to the Dissection of a Pig's Heart

ERIC Educational Resources Information Center

Lee, Yeung Chung

2004-01-01

The dissection of the mammalian heart in secondary biology classes need not be restricted to revealing the internal structure of the heart and its function. It could also be used to demonstrate other important aspects of blood circulation, including the blood supply to the heart itself as well as the causes and effects of coronary heart disease.…

A Practical Introduction to the XML, Extensible Markup Language, by Way of Some Useful Examples

ERIC Educational Resources Information Center

Snyder, Robin

2004-01-01

XML, Extensible Markup Language, is important as a way to represent and encapsulate the structure of underlying data in a portable way that supports data exchange regardless of the physical storage of the data. This paper (and session) introduces some useful and practical aspects of XML technology for sharing information in a educational setting…

Simulation of Electric Propulsion Thrusters

DTIC Science & Technology

2011-01-01

and operational lifetime. The second area of modelling activity concerns the plumes produced by electric thrusters. Detailed information on the plumes ...to reproduce the in-orbit space environment using ground-based laboratory facilities. Device modelling also plays an important role in plume ...of the numerical analysis of other aspects of thruster design, such as thermal and structural processes, is omitted here. There are two fundamental

Cross-Cultural Comparisons of University Students' Science Learning Self-Efficacy: Structural Relationships among Factors within Science Learning Self-Efficacy

ERIC Educational Resources Information Center

Wang, Ya-Ling; Liang, Jyh-Chong; Tsai, Chin-Chung

2018-01-01

Science learning self-efficacy could be regarded as a multi-factor belief which comprises different aspects such as cognitive skills, practical work, and everyday application. However, few studies have investigated the relationships among these factors that compose science learning self-efficacy. Also, culture may play an important role in…

Study of the Effect of Ellipsoidal Shape on the Kern and Frenkel Patch Model

NASA Astrophysics Data System (ADS)

Nguyen, Thienbao; Gunton, James; Rickman, Jeffrey

In their work on the self-assembly of complex structures, Glotzer and Solomon (Nature Materials 6, 557 - 562 (2007)) identified both interaction and shape anisotropy as two of several means to build complex structures. Advances in fabricating materials and new insights into protein biology have revealed the importance of these types of interactions. The Kern and Frenkel (J. Chem. Phys. 118, 9882 (2003) model of hard spheres carrying interaction patches of various sizes has been used extensively to describe interaction anisotropies important in protein phase transitions. However their model did not also account for shape anisotropy. We studied the role of both shape and interaction anisotropy by applying N=2 and N=4 attractive Kern and Frenkel patches with an interaction range to hard ellipsoids with various aspect ratios and patch coverages. Following Kern and Frenkel, we studied the liquid-liquid phase separation of our particles using a Monte Carlo simulation. We found the critical temperatures for our model using the approximate law of rectilinear diameter and compared them with the original results of Kern and Frenkel. We found that the critical temperatures increased both with aspect ratio and percent coverage. G Harold and Leila Y Mathers Foundation.

External and internal factors influencing self-directed online learning of physiotherapy undergraduate students in Sweden: a qualitative study

PubMed Central

Hammarlund, Catharina Sjödahl; Nilsson, Maria H.; Gummesson, Christina

2015-01-01

Purpose: Online courses have become common in health sciences education. This learning environment can be designed using different approaches to support student learning. To further develop online environment, it is important to understand how students perceive working and learning online. The aim of this study is to identify aspects influencing students’ learning processes and their adaptation to self-directed learning online. Methods: Thirty-four physiotherapy students with a mean age of 25 years (range, 21 to 34 years) participated. Qualitative content analysis and triangulation was used when investigating the students’ self-reflections, written during a five week self-directed, problem-oriented online course. Results: Two categories emerged: ‘the influence of the structured framework’ and ‘communication and interaction with teachers and peers.’ The learning processes were influenced by external factors, e.g., a clear structure including a transparent alignment of assignments and assessment. Important challenges to over-come were primarily internal factors, e.g., low self-efficacy, difficulties to plan the work effectively and adapting to a new environment. Conclusion: The analyses reflected important perspectives targeting areas which enable further course development. The influences of external and internal factors on learning strategies and self-efficacy are important aspects to consider when designing online courses. Factors such as pedagogical design, clarity of purpose, goals, and guidelines were important as well as continuous opportunities for communication and collaboration. Further studies are needed to understand and scaffold the motivational factors among students with low self-efficacy. PMID:26101401

Theory-based Bayesian models of inductive learning and reasoning.

PubMed

Tenenbaum, Joshua B; Griffiths, Thomas L; Kemp, Charles

2006-07-01

Inductive inference allows humans to make powerful generalizations from sparse data when learning about word meanings, unobserved properties, causal relationships, and many other aspects of the world. Traditional accounts of induction emphasize either the power of statistical learning, or the importance of strong constraints from structured domain knowledge, intuitive theories or schemas. We argue that both components are necessary to explain the nature, use and acquisition of human knowledge, and we introduce a theory-based Bayesian framework for modeling inductive learning and reasoning as statistical inferences over structured knowledge representations.

Mass Determination of Entire Amyloid Fibrils by Using Mass Spectrometry.

PubMed

Doussineau, Tristan; Mathevon, Carole; Altamura, Lucie; Vendrely, Charlotte; Dugourd, Philippe; Forge, Vincent; Antoine, Rodolphe

2016-02-12

Amyloid fibrils are self-assembled protein structures with important roles in biology (either pathogenic or physiological), and are attracting increasing interest in nanotechnology. However, because of their high aspect ratio and the presence of some polymorphism, that is, the possibility to adopt various structures, their characterization is challenging and basic information such as their mass is unknown. Here we show that charge-detection mass spectrometry, recently developed for large self-assembled systems such as viruses, provides such information in a straightforward manner. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

"What's in a structure?" The story of biguanides

NASA Astrophysics Data System (ADS)

Kathuria, Deepika; Bankar, Apoorva A.; Bharatam, Prasad V.

2018-01-01

Biguanides are a very interesting class of molecules which have been extensively studied for their medicinal applications. The structural and electronic structural aspects of biguanides have been explored in detail; however, even today, scientific literature continues to represent biguanides incorrectly as 1a. The X-ray crystal structure analysis and various spectroscopic studies such as UV, 1H and 15N NMR have confirmed that biguanide exists as tautomer 1b. Electronic structure analysis also supports the existence of 1b. This review focuses on the structure and electronic structure of biguanides and aims to emphasize the importance of the correct representation of a structure. There is a need to commence the use of 1b for the general representation of biguanides in textbooks and research articles which will ensure a correct perspective for further studies on these molecules.

Organizational Factors that Affect the Implementation of Information Technology: Perspectives of Middle Managers in Iran

PubMed Central

Barzekar, Hosein; Karami, Mahtab

2014-01-01

ABSTRACT Objective: to examine the organizational factors affecting the application of information technology in hospitals. Since the organizational factors are one of the most important determinants of successful projects, by understanding their impact and identifying them it can help planning a systematic IT implementation. Methods: In this cross-sectional descriptive study 110 middle managers were chosen from teaching hospitals. Structured questionnaire was used for the data collection. Results: There was a significant relationship between organization resource, organizational knowledge, process, management structure and values and goals with implementation of information technology. Conclusion: Findings showed that organizational factors had a considerable impact on implementation of information technology. Top managers must consider the important aspects of effective organizational factors. PMID:25568582

[Chronic Pelvic Pain Syndrome and Personality--Association of Somatic Symptoms and Psychic Structure].

PubMed

Albrecht, Rebecca; Löwe, Bernd; A Brünahl, Christian; Riegel, Björn

2015-11-01

Despite its high prevalence, little is known about the aetiology and maintenance of Chronic Pelvic Pain Syndrome (CPPS). CPPS is is considered to be a multi-causal syndrome with discomfort and pain in the pelvis. Recent literature suggests that psychosocial factors are important for understanding CPPS. For example, CPPS has been associated with deficits in mentalization and bonding experiences. Our study aims to characterize features of personality disorders according to DSM-IV and psychic structure according to OPD-2 in CPPS patients. Furthermore, we examine the association of personality aspects with urological symptoms (NIH Questionnaire) and pain perception (MPQ Questionnaire). Personality aspects were assessed in a total of 109 patients from our CPPS outpatient clinic using standardized questionnaires. To characterize CPPS patients, we compared the sample's scores with reference groups, mostly the general population. In addition, the associations between personality aspects and both the urologic symptoms and pain perception were assessed using correlations. Missing data were replaced using multiple imputation methods. Compared to reference values, we found 'experiencing emotions' and 'creating relationships' as specific deficits in CPPS patients. Furthermore, patients' self-image (more dominant, higher depressive mood) differs from the general population. A higher pain perception was correlated with deficits in most personality aspects we measured. However, this was not the case for the severity of urological symptoms. Compared to the reference values, only a few personality aspects differed in CPPS patients but there was a correlational association between different personality traits and pain perception. Despite the extend of symptoms, pain perception is associated with difficulty (emotional ability) in dealing with emotions, self-management and relationships. These personality aspects should be taken into account when planning therapy. © Georg Thieme Verlag KG Stuttgart · New York.

Membrane proteins structures: A review on computational modeling tools.

PubMed

Almeida, Jose G; Preto, Antonio J; Koukos, Panagiotis I; Bonvin, Alexandre M J J; Moreira, Irina S

2017-10-01

Membrane proteins (MPs) play diverse and important functions in living organisms. They constitute 20% to 30% of the known bacterial, archaean and eukaryotic organisms' genomes. In humans, their importance is emphasized as they represent 50% of all known drug targets. Nevertheless, experimental determination of their three-dimensional (3D) structure has proven to be both time consuming and rather expensive, which has led to the development of computational algorithms to complement the available experimental methods and provide valuable insights. This review highlights the importance of membrane proteins and how computational methods are capable of overcoming challenges associated with their experimental characterization. It covers various MP structural aspects, such as lipid interactions, allostery, and structure prediction, based on methods such as Molecular Dynamics (MD) and Machine-Learning (ML). Recent developments in algorithms, tools and hybrid approaches, together with the increase in both computational resources and the amount of available data have resulted in increasingly powerful and trustworthy approaches to model MPs. Even though MPs are elementary and important in nature, the determination of their 3D structure has proven to be a challenging endeavor. Computational methods provide a reliable alternative to experimental methods. In this review, we focus on computational techniques to determine the 3D structure of MP and characterize their binding interfaces. We also summarize the most relevant databases and software programs available for the study of MPs. Copyright © 2017 Elsevier B.V. All rights reserved.

Modelling and enhanced molecular dynamics to steer structure-based drug discovery.

PubMed

Kalyaanamoorthy, Subha; Chen, Yi-Ping Phoebe

2014-05-01

The ever-increasing gap between the availabilities of the genome sequences and the crystal structures of proteins remains one of the significant challenges to the modern drug discovery efforts. The knowledge of structure-dynamics-functionalities of proteins is important in order to understand several key aspects of structure-based drug discovery, such as drug-protein interactions, drug binding and unbinding mechanisms and protein-protein interactions. This review presents a brief overview on the different state of the art computational approaches that are applied for protein structure modelling and molecular dynamics simulations of biological systems. We give an essence of how different enhanced sampling molecular dynamics approaches, together with regular molecular dynamics methods, assist in steering the structure based drug discovery processes. Copyright © 2013 Elsevier Ltd. All rights reserved.

The importance of 'global meaning' for people rehabilitating from spinal cord injury.

PubMed

Littooij, E; Leget, C J W; Stolwijk-Swüste, J M; Doodeman, S; Widdershoven, G A M; Dekker, J

2016-11-01

Qualitative study. To explore whether aspects of global meaning (that is, fundamental beliefs and life goals concerning core values, relationships, worldview, identity and inner posture) are associated with processes and outcomes in rehabilitation, as experienced by people with spinal cord injury (SCI). People living in the community receiving outpatient rehabilitation in a Dutch rehabilitation center. In-depth semi-structured interviews were conducted with 16 people with SCI. Interviews were analyzed using qualitative research methods: structural and provisional coding. Core values, relationships, worldview, identity and inner posture (that is, the way in which people relate to the facts of life) were associated with various processes and outcomes of rehabilitation. Elements of the rehabilitation process included motivation, regulation of emotion, making decisions and handling stress. Elements of the outcome of rehabilitation included physical functioning, emotional functioning, social functioning and subjective sense of meaning. The influence was positive, with the exception of one case in which worldview and inner posture were negatively associated with motivation. Besides that, respondents emphasized the importance of rehabilitation professionals attuning to their global meaning. All aspects of global meaning were positively associated with various processes and outcomes of rehabilitation. It is recommended that rehabilitation professionals are aware of the importance of global meaning to people with SCI and that they take people's fundamental beliefs and life goals into account.

Genetic and orthopedic aspects of collagen disorders.

PubMed

Carter, Erin M; Raggio, Cathleen L

2009-02-01

'Collagens' are a family of structurally related proteins that play a wide variety of roles in the extracellular matrix. To date, there are at least 29 known types of collagen. Accordingly, abnormality in the various collagens produces a large category of diseases with heterogeneous symptoms. This review presents genetic and orthopedic aspects of type II, IX, and XI collagen disorders. Although a diverse group of conditions, mutation of collagens affecting the articular cartilage typically produces an epiphyseal skeletal dysplasia phenotype. Often, the ocular or auditory systems or both are also involved. Treatment of these collagenopathies is symptomatic and individualized. Study of tissue from animal models allows examination of mutation effects on the abnormal protein structure and function. The collagen superfamily comprises an important structural protein in mammalian connective tissue. Mutation of collagens produces a wide variety of genetic disorders, and those mutations affecting types II, IX, and XI collagens produce an overlapping spectrum of skeletal dysplasias. Findings range from lethal to mild, depending on the mutation of the collagen gene and its subsequent effect on the structure and/or metabolism of the resultant procollagen and/or collagen protein and its function in the body.

Adding the Third Dimension to Virus Life Cycles: Three-Dimensional Reconstruction of Icosahedral Viruses from Cryo-Electron Micrographs

PubMed Central

Baker, T. S.; Olson, N. H.; Fuller, S. D.

1999-01-01

Viruses are cellular parasites. The linkage between viral and host functions makes the study of a viral life cycle an important key to cellular functions. A deeper understanding of many aspects of viral life cycles has emerged from coordinated molecular and structural studies carried out with a wide range of viral pathogens. Structural studies of viruses by means of cryo-electron microscopy and three-dimensional image reconstruction methods have grown explosively in the last decade. Here we review the use of cryo-electron microscopy for the determination of the structures of a number of icosahedral viruses. These studies span more than 20 virus families. Representative examples illustrate the use of moderate- to low-resolution (7- to 35-Å) structural analyses to illuminate functional aspects of viral life cycles including host recognition, viral attachment, entry, genome release, viral transcription, translation, proassembly, maturation, release, and transmission, as well as mechanisms of host defense. The success of cryo-electron microscopy in combination with three-dimensional image reconstruction for icosahedral viruses provides a firm foundation for future explorations of more-complex viral pathogens, including the vast number that are nonspherical or nonsymmetrical. PMID:10585969

Effect of regional slopes on local structure and exploration of tilted paleo-highs

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

Nazarov, D.A.; Chernobrov, B.S.

1986-06-01

Prospects for discovering local highs in old petroleum-producing regions have by now been substantially exhausted. Hence it is of great importance at this stage to seek non-anticlinal accumulations of hydrocarbons, including those in traps genetically associated with tilted paleo-highs, often represented in the modern structural plan by structural noses and terraces. Appropriate exploration for such types of deposits may soon become important in Ciscaucasia and other old petroleum-producing regions. Consequently, problems of the scientific basis for prospecting paleo-highs tilted in the modern structural plan, and developing procedures both for revealing and also for assessing their expression in the structural planmore » during different stages of geological history, and establishing the time and depth of changes in aspect, will become extremely topical. In order to discover possible local highs and to study their features within the margins of the platformal basins and the platformal edges of the marginal troughs, the authors use the method of removing the effect of the regional slope on the local structural plan. This paper describes this method. 13 references.« less

3D printing strategies for peripheral nerve regeneration.

PubMed

Petcu, Eugen B; Midha, Rajiv; McColl, Erin; Popa-Wagner, Aurel; Chirila, Traian V; Dalton, Paul D

2018-03-23

After many decades of biomaterials research for peripheral nerve regeneration, a clinical product (the nerve guide), is emerging as a proven alternative for relatively short injury gaps. This review identifies aspects where 3D printing can assist in improving long-distance nerve guide regeneration strategies. These include (1) 3D printing of the customizable nerve guides, (2) fabrication of scaffolds that fill nerve guides, (3) 3D bioprinting of cells within a matrix/bioink into the nerve guide lumen and the (4) establishment of growth factor gradients along the length a nerve guide. The improving resolution of 3D printing technologies will be an important factor for peripheral nerve regeneration, as fascicular-like guiding structures provide one path to improved nerve guidance. The capability of 3D printing to manufacture complex structures from patient data based on existing medical imaging technologies is an exciting aspect that could eventually be applied to treating peripheral nerve injury. Ultimately, the goal of 3D printing in peripheral nerve regeneration is the automated fabrication, potentially customized for the patient, of structures within the nerve guide that significantly outperform the nerve autograft over large gap injuries.

Revisiting the mechanism of coagulation factor XIII activation and regulation from a structure/functional perspective

PubMed Central

Gupta, Sneha; Biswas, Arijit; Akhter, Mohammad Suhail; Krettler, Christoph; Reinhart, Christoph; Dodt, Johannes; Reuter, Andreas; Philippou, Helen; Ivaskevicius, Vytautas; Oldenburg, Johannes

2016-01-01

The activation and regulation of coagulation Factor XIII (FXIII) protein has been the subject of active research for the past three decades. Although discrete evidence exists on various aspects of FXIII activation and regulation a combinatorial structure/functional view in this regard is lacking. In this study, we present results of a structure/function study of the functional chain of events for FXIII. Our study shows how subtle chronological submolecular changes within calcium binding sites can bring about the detailed transformation of the zymogenic FXIII to its activated form especially in the context of FXIIIA and FXIIIB subunit interactions. We demonstrate what aspects of FXIII are important for the stabilization (first calcium binding site) of its zymogenic form and the possible modes of deactivation (thrombin mediated secondary cleavage) of the activated form. Our study for the first time provides a structural outlook of the FXIIIA2B2 heterotetramer assembly, its association and dissociation. The FXIIIB subunits regulatory role in the overall process has also been elaborated upon. In summary, this study provides detailed structural insight into the mechanisms of FXIII activation and regulation that can be used as a template for the development of future highly specific therapeutic inhibitors targeting FXIII in pathological conditions like thrombosis. PMID:27453290

Population genetic structure of codling moth (Lepidoptera: Tortricidae) from apple orchards in central Chile.

PubMed

Fuentes-Contreras, Eduardo; Espinoza, Juan L; Lavandero, Blas; Ramírez, Claudio C

2008-02-01

Codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), is the main pest of pome fruits worldwide. Despite its economic importance, little is known about the genetic structure and patterns of dispersal at the local and regional scale, which are important aspects for establishing a control strategy for this pest. An analysis of genetic variability using microsatellites was performed for 11 codling moth populations in the two major apple (Malus domestica Borkh) cropping regions in central Chile. Despite the geographical distances between some populations (approximately 185 km), there was low genetic differentiation among populations (F(ST) = 0.002176), with only slight isolation by distance. Only approximately 0.2% of the genetic variability was found among the populations. Geographically structured genetic variation was independent of apple orchard management (production or abandoned). These results suggest a high genetic exchange of codling moth between orchards, possibly mediated by human activities related to fruit production.

The inner formal structure of the H-T-P drawings: an exploratory study.

PubMed

Vass, Z

1998-08-01

The study describes some interrelated patterns of traits of the House-Tree-Person (H-T-P) drawings with the instruments of hierarchical cluster analysis. First, according to the literature 1 7 formal or structural aspects of the projective drawings were collected, after which a detailed manual for coding was compiled. Second, the interrater reliability and the consistency of this manual was tested. Third, the hierarchical cluster structure of the reliable and consistent formal aspects was analysed. Results are: (a) a psychometrically tested coding manual of the investigated formal-structural aspects, each of them illustrated with drawings that showed the highest interrater agreement; and (b) the hierarchic cluster structure of the formal aspects of the H-T-P drawings of "normal" adults.

Micro-structure and motion of two-dimensional dense short spherocylinder liquids

NASA Astrophysics Data System (ADS)

Wang, Wen; Lin, Jyun-Ting; Su, Yen-Shuo; I, Lin

2018-03-01

We numerically investigate the micro-structure and motion of 2D liquids composed of dense short spherocylinders, by reducing the shape aspect ratio from 3. It is found that reducing shape aspect ratio from 3 causes a smooth transition from heterogeneous structures composed of crystalline ordered domains with good tetratic alignment order to those with good hexagonal bond-orientational order at an aspect ratio equaling 1.35. In the intermediate regime, both structural orders are strongly deteriorated, and the translational hopping rate reaches a maximum due to the poor particle interlocking of the disordered structure. Shortening rod length allows easier rotation, induces monotonic increase of rotational hopping rates, and resumes the separation of rotational and translational hopping time scales at the small aspect ratio end, after the crossover of their rates in the intermediate regime. At the large shape aspect ratio end, the poor local tetratic order has the same positive effects on facilitating local rotational and translational hopping. In contrast, at the small shape aspect ratio end, the poor local bond orientational order has the opposite effects on facilitating local rotational and translational hopping.

Interactive anatomical teaching: Integrating radiological anatomy within topographic anatomy.

PubMed

Abed Rabbo, F; Garrigues, F; Lefèvre, C; Seizeur, R

2016-03-01

Hours attributed to teaching anatomy have been reduced in medical curricula through out the world. In consequence, changes in anatomical curriculum as well as in teaching methods are becoming necessary. New methods of teaching are being evaluated. We present in the following paper an example of interactive anatomical teaching associating topographic anatomy with ultrasonographic radiological anatomy. The aim was to explicitly show anatomical structures of the knee and the ankle through dissection and ultrasonography. One cadaver was used as an ultrasonographic model and the other was dissected. Anatomy of the knee and ankle articulations was studied through dissection and ultrasonography. The students were able to simultaneously assimilate both anatomical aspects of radiological and topographic anatomy. They found the teaching very helpful and practical. This body of work provides example of a teaching method combining two important aspects of anatomy to help the students understand both aspects simultaneously. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

The Digestive System [and] Instructor's Guide. Instructional Materials in Anatomy and Physiology for Pennsylvania Health Occupations Programs.

ERIC Educational Resources Information Center

National Evaluation Systems, Inc., Amherst, MA.

This instructional modular unit wlth instructor's guide provides materials on important aspects of one of the major systems of the human body--the digestive system. Its purpose is to introduce the student to the structures and functions of the human digestive system--and the interrelationships of the two--and to familiarize the student with some…

The Role of Leadership Practices on Job Stress among Malay Academic Staff: A Structural Equation Modeling Analysis

ERIC Educational Resources Information Center

Safaria, Triantoro; bin Othman, Ahmad; Wahab, Muhammad Nubli Abdul

2011-01-01

Globalization brings change in all aspect of human life, including in how job and organizations operate. These changes create strain and stress not only among employee at business organization, but also among academic staff. The dean of faculty or department at university has important role in prevent the effects of job stress among the academic…

Employer-Sponsored Recurrent Education in the United States: A Report on Recent Inquiries into Its Structure.

ERIC Educational Resources Information Center

Smith, G. B.

Employer-sponsored recurrent (or lifelong) learning has grown from its World War II beginnings to become a large, important, but little-studied aspect of American education, one with major implications for the U.S. economy and society. U.S. employers spend from 20 to 100 billion dollars on educational programs for anywhere from 37 to 73 million…

The valuation of health care intangible assets.

PubMed

Reilly, R F; Rabe, J R

1997-01-01

Health care entities (and especially medical practices) are valued for a number of reasons: sale transaction pricing and structuring, merger formation and dissolution, taxation and regulatory compliance, and litigation support and dispute resolution. The identification and quantification of the entity's intangible assets are often the most important aspects of the valuation. This article illustrates the generally accepted methods for valuing health care-related intangible assets.

Identity related to living situation in six individuals with congenital quadriplegia.

PubMed

Robey, Kenneth L

2008-01-01

This study was a preliminary examination of structural aspects of identity, particularly identity associated with living situation, in individuals who have quadriplegia due to cerebral palsy. A hierarchical classes algorithm (HICLAS) was used to construct idiographic 'identity structure' models for three individuals who are living in an inpatient hospital setting and for three individuals living in community-based group residences. Indices derived from the models indicate that the identity 'myself as one who has a disability' was structurally superordinate (i.e., resided at a high hierarchical level) for all six participants, suggesting a high level of importance of this identity in participants' sense of self. The models also indicate that while identity associated with one's particular living situation was superordinate for persons living in the hospital, it was not for persons living in community residences. While conclusions based on this small sample are necessarily limited, the data suggest that identity associated with living situation might differ in structural centrality, and presumably subjective importance, for persons living in inpatient versus community-based settings.

Software engineering aspects of real-time programming concepts

NASA Astrophysics Data System (ADS)

Schoitsch, Erwin

1986-08-01

Real-time programming is a discipline of great importance not only in process control, but also in fields like communication, office automation, interactive databases, interactive graphics and operating systems development. General concepts of concurrent programming and constructs for process-synchronization are discussed in detail. Tasking and synchronization concepts, methods of process communication, interrupt and timeout handling in systems based on semaphores, signals, conditional critical regions or on real-time languages like Concurrent PASCAL, MODULA, CHILL and ADA are explained and compared with each other. The second part deals with structuring and modularization of technical processes to build reliable and maintainable real time systems. Software-quality and software engineering aspects are considered throughout the paper.

New Perspectives on Tooth Wear

PubMed Central

Lucas, Peter W.; Omar, Ridwaan

2012-01-01

Some of the efforts that have been made to document tooth wear are reviewed here with an emphasis on nonhuman mammals, literature with which dentists may not be very familiar. We project a change in research strategy from the description of wear at various scales of measurement towards investigation of the mechanical mechanisms that actually create the texture of a worn surface. These studies should reveal exactly how tooth tissue is lost and what aspects of the structure of dental tissues affect this. The most important aspects of the interaction between the tooth surface and wear particles would appear to be particle size, particle shape, their mechanical properties with respect to those of tooth tissues, and the influence of saliva. PMID:22536239

Molecular features of grass allergens and development of biotechnological approaches for allergy prevention.

PubMed

Devis, Deborah L; Davies, Janet M; Zhang, Dabing

2017-09-01

Allergic diseases are characterized by elevated allergen-specific IgE and excessive inflammatory cell responses. Among the reported plant allergens, grass pollen and grain allergens, derived from agriculturally important members of the Poaceae family such as rice, wheat and barley, are the most dominant and difficult to prevent. Although many allergen homologs have been predicted from species such as wheat and timothy grass, fundamental aspects such as the evolution and function of plant pollen allergens remain largely unclear. With the development of genetic engineering and genomics, more primary sequences, functions and structures of plant allergens have been uncovered, and molecular component-based allergen-specific immunotherapies are being developed. In this review, we aim to provide an update on (i) the distribution and importance of pollen and grain allergens of the Poaceae family, (ii) the origin and evolution, and functional aspects of plant pollen allergens, (iii) developments of allergen-specific immunotherapy for pollen allergy using biotechnology and (iv) development of less allergenic plants using gene engineering techniques. We also discuss future trends in revealing fundamental aspects of grass pollen allergens and possible biotechnological approaches to reduce the amount of pollen allergens in grasses. Copyright © 2017. Published by Elsevier Inc.

The what, where, how and why of gene ontology—a primer for bioinformaticians

PubMed Central

du Plessis, Louis; Škunca, Nives

2011-01-01

With high-throughput technologies providing vast amounts of data, it has become more important to provide systematic, quality annotations. The Gene Ontology (GO) project is the largest resource for cataloguing gene function. Nonetheless, its use is not yet ubiquitous and is still fraught with pitfalls. In this review, we provide a short primer to the GO for bioinformaticians. We summarize important aspects of the structure of the ontology, describe sources and types of functional annotations, survey measures of GO annotation similarity, review typical uses of GO and discuss other important considerations pertaining to the use of GO in bioinformatics applications. PMID:21330331

Virtual screening of compound libraries.

PubMed

Cerqueira, Nuno M F S A; Sousa, Sérgio F; Fernandes, Pedro A; Ramos, Maria João

2009-01-01

During the last decade, Virtual Screening (VS) has definitively established itself as an important part of the drug discovery and development process. VS involves the selection of likely drug candidates from large libraries of chemical structures by using computational methodologies, but the generic definition of VS encompasses many different methodologies. This chapter provides an introduction to the field by reviewing a variety of important aspects, including the different types of virtual screening methods, and the several steps required for a successful virtual screening campaign within a state-of-the-art approach, from target selection to postfilter application. This analysis is further complemented with a small collection important VS success stories.

Integrating the epistemic and ontological aspects of content knowledge in science teaching and learning

NASA Astrophysics Data System (ADS)

Papadouris, Nicos; Constantinou, Constantinos P.

2017-04-01

Promoting facility with content knowledge is one of the most important objectives of science teaching. Conventionally, the focus for this objective is placed on the substantive side of content knowledge (e.g. science concepts/laws), whereas its epistemic or ontological aspects (e.g. why do we construct concepts?) rarely receive explicit attention. In this article, we develop a theoretical argument for the value of elevating the attention paid to the epistemic/ontological aspects of content knowledge and integrating them with its substantive side. Our argument is structured in two parts. The first unpacks the epistemic/ontological aspects of content knowledge and their role in science. For this, we focus on two specific aspects (i.e. ontological status and epistemic value of science concepts), which we elaborate in the context of two particular content domains, namely magnetism and energy. The second part of the argument highlights the potential of discourse on epistemic/ontological aspects to facilitate learning in science. We delineate how such discourse could (a) promote coherent conceptual understanding, (b) foster a productive epistemological stance towards science learning, and (c) enhance students' appreciation of ideas associated with the nature of science. The article concludes with a discussion of ensuing implications for science education.

Depth elemental characterization of 1D self-aligned TiO2 nanotubes using calibrated radio frequency glow discharge optical emission spectroscopy (GDOES)

NASA Astrophysics Data System (ADS)

Mohajernia, Shiva; Mazare, Anca; Hwang, Imgon; Gaiaschi, Sofia; Chapon, Patrick; Hildebrand, Helga; Schmuki, Patrik

2018-06-01

In this work we study the depth composition of anodic TiO2 nanotube layers. We use elemental depth profiling with Glow Discharge Optical Emission Spectroscopy and calibrate the results of this technique with X-ray photoelectron spectroscopy (XPS) and energy dispersive spectroscopy (EDS). We establish optimized sputtering conditions for nanotubular structures using the pulsed RF mode, which causes minimized structural damage during the depth profiling of the nanotubular structures. This allows to obtain calibrated sputter rates that account for the nanotubular "porous" morphology. Most importantly, sputter-artifact free compositional profiles of these high aspect ratio 3D structures are obtained, as well as, in combination with SEM, elegant depth sectional imaging.

Multiscale Micromechanical Modeling of Polymer/Clay Nanocomposites and the Effective Clay Particle

NASA Astrophysics Data System (ADS)

Sheng, Nuo; Boyce, Mary C.; Parks, David M.; Manovitch, Oleg; Rutledge, Gregory C.; Lee, Hojun; McKinley, Gareth H.

2003-03-01

Polymer/clay nanocomposites have been observed to exhibit enhanced mechanical properties at low weight fractions (Wp) of clay. Continuum-based composite modeling reveals that the enhanced properties are strongly dependent on particular features of the second-phase ¡°particles¡+/-; in particular, the particle volume fraction (fp), the particle aspect ratio (L/t), and the ratio of particle mechanical properties to those of the matrix. However, these important aspects of as-processed nanoclay composites have yet to be consistently and accurately defined. A multiscale modeling strategy was developed to account for the hierarchical morphology of the nanocomposite: at a lengthscale of thousands of microns, the structure is one of high aspect ratio particles within a matrix; at the lengthscale of microns, the clay particle structure is either (a) exfoliated clay sheets of nanometer level thickness or (b) stacks of parallel clay sheets separated from one another by interlayer galleries of nanometer level height. Here, quantitative structural parameters extracted from XRD patterns and TEM micrographs are used to determine geometric features of the as-processed clay ¡°particles¡+/-, including L/t and the ratio of fp to Wp. These geometric features, together with estimates of silicate lamina stiffness obtained from molecular dynamics simulations, provide a basis for modeling effective mechanical properties of the clay particle. The structure-based predictions of the macroscopic elastic modulus of the nanocomposite as a function of clay weight fraction are in excellent agreement with experimental data. The adopted methodology offers promise for study of related properties in polymer/clay nanocomposites.

Structural insights into ligand recognition and selectivity for class A, B, and C GPCRs

PubMed Central

Lee, Sang-Min; Booe, Jason M.; Pioszak, Augen A.

2015-01-01

The G protein-coupled receptor (GPCR) superfamily constitutes the largest collection of cell surface signaling proteins with approximately 800 members in the human genome. GPCRs regulate virtually all aspects of physiology and they are an important class of drug targets with ~30% of drugs on the market targeting a GPCR. Breakthroughs in GPCR structural biology in recent years have significantly expanded our understanding of GPCR structure and function and ushered in a new era of structure-based drug design for GPCRs. Crystal structures for nearly thirty distinct GPCRs are now available including receptors from each of the major classes, A, B, C, and F. These structures provide a foundation for understanding the molecular basis of GPCR pharmacology. Here, we review structural mechanisms of ligand recognition and selectivity of GPCRs with a focus on selected examples from classes A, B, and C, and we highlight major unresolved questions for future structural studies. PMID:25981303

A Summary of Numerous Strain-Gage Load Calibrations on Aircraft Wings and Tails in a Technological Format

NASA Technical Reports Server (NTRS)

Jenkins, Jerald M.; DeAngelis, V. Michael

1997-01-01

Fifteen aircraft structures that were calibrated for flight loads using strain gages are examined. The primary purpose of this paper is to document important examples of load calibrations on airplanes during the past four decades. The emphasis is placed on studying the physical procedures of calibrating strain-gaged structures and all the supporting analyses and computational techniques that have been used. The results and experiences obtained from actual data from 14 structures (on 13 airplanes and 1 laboratory test structure) are presented. This group of structures includes fins, tails, and wings with a wide variety of aspect ratios. Straight- wing, swept-wing, and delta-wing configurations are studied. Some of the structures have skin-dominant construction; others are spar-dominant. Anisotropic materials, heat shields, corrugated components, nonorthogonal primary structures, and truss-type structures are particular characteristics that are included.

Faunal impact on vegetation structure and ecosystem function in mangrove forests: A review

USGS Publications Warehouse

Cannicci, Stefano; Burrows, Damien; Fratini, Sara; Smith, Thomas J.; Offenberg, Joachim; Dahdouh-Guebas, Farid

2008-01-01

The last 20 years witnessed a real paradigm shift concerning the impact of biotic factors on ecosystem functions as well as on vegetation structure of mangrove forests. Before this small scientific revolution took place, structural aspects of mangrove forests were viewed to be the result of abiotic processes acting from the bottom-up, while, at ecosystem level, the outwelling hypothesis stated that mangroves primary production was removed via tidal action and carried to adjacent nearshore ecosystems where it fuelled detrital based food-webs. The sesarmid crabs were the first macrofaunal taxon to be considered a main actor in mangrove structuring processes, thanks to a number of studies carried out in the Indo-Pacific forests in the late 1970s and early 1980s. Following these classical papers, a number of studies on Sesarmidae feeding and burrowing ecology were carried out, which leave no doubts about the great importance of these herbivorous crabs in structuring and functioning Old world ecosystems. Although Sesarmidae are still considered very important in shaping mangrove structure and functioning, recent literature emphasizes the significance of other invertebrates. The Ocypodidae have now been shown to have the same role as Sesarmidae in terms of retention of forest products and organic matter processing in New world mangroves. In both New and Old world mangroves, crabs process large amounts of algal primary production, contribute consistently to retention of mangrove production and as ecosystem engineers, change particle size distribution and enhance soil aeration. Our understanding of the strong impact of gastropods, by means of high intake rates of mangrove products and differential consumption of propagules, has changed only recently. The role of insects must also be stressed. It is now clear that older techniques used to assess herbivory rates by insects strongly underestimate their impact, both in case of leaf eating and wood boring species and that herbivorous insects can potentially play a strong role in many aspects of mangrove ecology. Moreover, researchers only recently realized that ant–plant interactions may form an important contribution to our understanding of insect–plant dynamics in these habitats. Ants seem to be able to relieve mangroves from important herbivores such as many insects and sesarmid crabs. It thus seems likely that ants have positive effects on mangrove performance.

The cultural specifity of research ethics—or why ethical debate in France is different

PubMed Central

Maio, G

2002-01-01

In the search for a globally binding ethical minimal consensus in dealing with research on human beings the awareness of the cultural specificity of such questions will be of central importance. France provides a good example of such cultural specificities. Three basic structures of French discussion on research ethics can be enumerated: first the particular weight placed on therapeutic benefit, second a particular accentuation on freedom and voluntarism, and third its lesser attention to the aspect of ability to give consent. The weak emphasis on the ability to give consent is rooted as much in the traditionally paternalistically imbued physician-patient relationship as in the French legal system, in which the doctrine of consent is not given the fundamental position of importance found in the Anglo-Saxon countries. As an important Roman country, a different accentuation in the ethical discussion on research on humans can be recognised, a discussion in which for a long time the right of self determination was less of a criterion for decision than the teleology of medical action. It is precisely this aspect of latent cultural influence in ethical convictions which is of decisive importance for future discussion on research on humans. PMID:12042397

Constructing a self: the role of self-structure and self-certainty in social anxiety.

PubMed

Stopa, Lusia; Brown, Mike A; Luke, Michelle A; Hirsch, Colette R

2010-10-01

Current cognitive models stress the importance of negative self-perceptions in maintaining social anxiety, but focus predominantly on content rather than structure. Two studies examine the role of self-structure (self-organisation, self-complexity, and self-concept clarity) in social anxiety. In study one, self-organisation and self-concept clarity were correlated with social anxiety, and a step-wise multiple regression showed that after controlling for depression and self-esteem, which explained 35% of the variance in social anxiety scores, self-concept clarity uniquely predicted social anxiety and accounted for an additional 7% of the variance in social anxiety scores in an undergraduate sample (N=95) and the interaction between self-concept clarity and compartmentalisation (an aspect of evaluative self-organisation) at step 3 of the multiple regression accounted for a further 3% of the variance in social anxiety scores. In study two, high (n=26) socially anxious participants demonstrated less self-concept clarity than low socially anxious participants (n=26) on both self-report (used in study one) and on computerised measures of self-consistency and confidence in self-related judgments. The high socially anxious group had more compartmentalised self-organisation than the low anxious group, but there were no differences between the two groups on any of the other measures of self-organisation. Self-complexity did not contribute to social anxiety in either study, although this may have been due to the absence of a stressor. Overall, the results suggest that self-structure has a potentially important role in understanding social anxiety and that self-concept clarity and other aspects of self-structure such as compartmentalisation interact with each other and could be potential maintaining factors in social anxiety. Cognitive therapy for social phobia might influence self-structure, and understanding the role of structural variables in maintenance and treatment could eventually help to improve treatment outcome. Copyright 2010 Elsevier Ltd. All rights reserved.

Constructing a self: The role of self-structure and self-certainty in social anxiety

PubMed Central

Stopa, Lusia; Brown, Mike A.; Luke, Michelle A.; Hirsch, Colette R.

2010-01-01

Current cognitive models stress the importance of negative self-perceptions in maintaining social anxiety, but focus predominantly on content rather than structure. Two studies examine the role of self-structure (self-organisation, self-complexity, and self-concept clarity) in social anxiety. In study one, self-organisation and self-concept clarity were correlated with social anxiety, and a step-wise multiple regression showed that after controlling for depression and self-esteem, which explained 35% of the variance in social anxiety scores, self-concept clarity uniquely predicted social anxiety and accounted for an additional 7% of the variance in social anxiety scores in an undergraduate sample (N = 95) and the interaction between self-concept clarity and compartmentalisation (an aspect of evaluative self-organisation) at step 3 of the multiple regression accounted for a further 3% of the variance in social anxiety scores. In study two, high (n = 26) socially anxious participants demonstrated less self-concept clarity than low socially anxious participants (n = 26) on both self-report (used in study one) and on computerised measures of self-consistency and confidence in self-related judgments. The high socially anxious group had more compartmentalised self-organisation than the low anxious group, but there were no differences between the two groups on any of the other measures of self-organisation. Self-complexity did not contribute to social anxiety in either study, although this may have been due to the absence of a stressor. Overall, the results suggest that self-structure has a potentially important role in understanding social anxiety and that self-concept clarity and other aspects of self-structure such as compartmentalisation interact with each other and could be potential maintaining factors in social anxiety. Cognitive therapy for social phobia might influence self-structure, and understanding the role of structural variables in maintenance and treatment could eventually help to improve treatment outcome. PMID:20800751

Teachers’ perceptions of aspects affecting seminar learning: a qualitative study

PubMed Central

2013-01-01

Background Many medical schools have embraced small group learning methods in their undergraduate curricula. Given increasing financial constraints on universities, active learning groups like seminars (with 25 students a group) are gaining popularity. To enhance the understanding of seminar learning and to determine how seminar learning can be optimised it is important to investigate stakeholders’ views. In this study, we qualitatively explored the views of teachers on aspects affecting seminar learning. Methods Twenty-four teachers with experience in facilitating seminars in a three-year bachelor curriculum participated in semi-structured focus group interviews. Three focus groups met twice with an interval of two weeks led by one moderator. Sessions were audio taped, transcribed verbatim and independently coded by two researchers using thematic analysis. An iterative process of data reduction resulted in emerging aspects that influence seminar learning. Results Teachers identified seven key aspects affecting seminar learning: the seminar teacher, students, preparation, group functioning, seminar goals and content, course coherence and schedule and facilities. Important components of these aspects were: the teachers’ role in developing seminars (‘ownership’), the amount and quality of preparation materials, a non-threatening learning climate, continuity of group composition, suitability of subjects for seminar teaching, the number and quality of seminar questions, and alignment of different course activities. Conclusions The results of this study contribute to the unravelling of the ‘the black box’ of seminar learning. Suggestions for ways to optimise active learning in seminars are made regarding curriculum development, seminar content, quality assurance and faculty development. PMID:23399475

Quantum chemical modeling of enzymatic reactions: the case of histone lysine methyltransferase.

PubMed

Georgieva, Polina; Himo, Fahmi

2010-06-01

Quantum chemical cluster models of enzyme active sites are today an important and powerful tool in the study of various aspects of enzymatic reactivity. This methodology has been applied to a wide spectrum of reactions and many important mechanistic problems have been solved. Herein, we report a systematic study of the reaction mechanism of the histone lysine methyltransferase (HKMT) SET7/9 enzyme, which catalyzes the methylation of the N-terminal histone tail of the chromatin structure. In this study, HKMT SET7/9 serves as a representative case to examine the modeling approach for the important class of methyl transfer enzymes. Active site models of different sizes are used to evaluate the methodology. In particular, the dependence of the calculated energies on the model size, the influence of the dielectric medium, and the particular choice of the dielectric constant are discussed. In addition, we examine the validity of some technical aspects, such as geometry optimization in solvent or with a large basis set, and the use of different density functional methods. Copyright 2010 Wiley Periodicals, Inc.

Farmers' perception of the role of veterinary surgeons in vaccination strategies on British dairy farms.

PubMed

Richens, I F; Hobson-West, P; Brennan, M L; Lowton, R; Kaler, J; Wapenaar, W

2015-11-07

There is limited research investigating the motivators and barriers to vaccinating dairy cattle. Veterinary surgeons have been identified as important sources of information for farmers making vaccination and disease control decisions, as well as being farmers' preferred vaccine suppliers. Vets' perception of their own role and communication style can be at odds with farmers' reported preferences. The objective of this study was to investigate how dairy farmers perceived the role of vets in implementing vaccination strategies on their farm. Semi-structured interviews were conducted with 24 dairy farmers from across Britain. The data were analysed using thematic analysis. Analysis revealed that farmers perceive vets to have an important role in facilitating decision-making in all aspects of vaccination, including the aspects of vaccine distribution and advice on implementation. This important role is acknowledged by farmers who have regular veterinary contact, but also farmers with solely emergency veterinary contact. Given this finding, future work should investigate the attitudes of vets towards vaccination and how they perceive their role. Combining this knowledge will enable optimisation of vaccination strategies on British dairy farms. British Veterinary Association.

A Rational Approach to Determine Minimum Strength Thresholds in Novel Structural Materials

NASA Technical Reports Server (NTRS)

Schur, Willi W.; Bilen, Canan; Sterling, Jerry

2003-01-01

Design of safe and survivable structures requires the availability of guaranteed minimum strength thresholds for structural materials to enable a meaningful comparison of strength requirement and available strength. This paper develops a procedure for determining such a threshold with a desired degree of confidence, for structural materials with none or minimal industrial experience. The problem arose in attempting to use a new, highly weight-efficient structural load tendon material to achieve a lightweight super-pressure balloon. The developed procedure applies to lineal (one dimensional) structural elements. One important aspect of the formulation is that it extrapolates to expected probability distributions for long length specimen samples from some hypothesized probability distribution that has been obtained from a shorter length specimen sample. The use of the developed procedure is illustrated using both real and simulated data.

Selected Topics in Light Front Field Theory and Applications to the High Energy Phenomena

NASA Astrophysics Data System (ADS)

Kundu, Rajen

1999-10-01

In this thesis, we have presented some of the aspects of light-front (LF) field theory through their successful application in the Deep Inelastic Scattering (DIS). We have developed a LFQCD Hamiltonian description of the DIS structure functions starting from Bjorken-Johnson-Low limit of virtual forward Compton scattering amplitude and using LF current commutators. We worked in the LF gauge A^+=0 and used the old-fashioned LFQCD perturbation theory in our calculations. The importance of our work are summarized below. Our approach shares the intution of parton model and addresses directly the structure functions, which are experimental objects, instead of its moments as in OPE method. Moreover, it can potentially incorporate the non-perturbative contents of the structure functions as we have demonstrated by introducing a new factorization scheme. In the context of nucleonic helicity structure, the well known gauge fixed LF helicity operator is shown to provide consistent physical information and helps us defining new relevant structure functions. The anomalous dimensions relevant for the Q^2-evolution of such structure functions are calculated. Our study is important in establishing the equivalance of LF field theory and the usual equal-time one through perturbative calculations of the dressed parton structure functions reproducing the well known results. Also the importance of Gallilean boost symmetry in understanding the correctness of any higher order calculation using (x^+)-ordered LFQCD perturbation theory are emphasized.

Towards a portal and search engine to facilitate academic and research collaboration in engineering and education

NASA Astrophysics Data System (ADS)

Bonilla Villarreal, Isaura Nathaly

While international academic and research collaborations are of great importance at this time, it is not easy to find researchers in the engineering field that publish in languages other than English. Because of this disconnect, there exists a need for a portal to find Who's Who in Engineering Education in the Americas. The objective of this thesis is to built an object-oriented architecture for this proposed portal. The Unified Modeling Language (UML) model developed in this thesis incorporates the basic structure of a social network for academic purposes. Reverse engineering of three social networks portals yielded important aspects of their structures that have been incorporated in the proposed UML model. Furthermore, the present work includes a pattern for academic social networks..

The Evolution of Networks in Extreme and Isolated Environment

NASA Technical Reports Server (NTRS)

Johnson, Jeffrey C.; Boster, James S.; Palinkas, Lawrence A.

2000-01-01

This article reports on the evolution of network structure as it relates to the formal and informal aspects of social roles in well bounded, isolated groups. Research was conducted at the Amundsen-Scott South Pole Station over a 3-year period. Data was collected on crewmembers' networks of social interaction and personal advice over each of the 8.5-month winters during a time of complete isolation. In addition, data was collected on informal social role structure (e.g., instrumental leadership, expressive leadership). It was hypothesized that development and maintenance of a cohesive group structure was related to the presence of and group consensus on various informal social roles. The study found that core-periphery structures (i.e., reflecting cohesion) in winter-over groups were associated with the presence of critically important informal social roles (e.g., expressive leadership) and high group consensus on such informal roles. On the other hand, the evolution of clique structures (i.e., lack of cohesion) were associated with the absence of critical roles and a lack of consensus on these roles, particularly the critically important role of instrumental leader.

The impact of recent improvements in cryo-electron microscopy technology on the understanding of bacterial ribosome assembly

PubMed Central

Razi, Aida; Britton, Robert A.

2017-01-01

Abstract Cryo-electron microscopy (cryo-EM) had played a central role in the study of ribosome structure and the process of translation in bacteria since the development of this technique in the mid 1980s. Until recently cryo-EM structures were limited to ∼10 Å in the best cases. However, the recent advent of direct electron detectors has greatly improved the resolution of cryo-EM structures to the point where atomic resolution is now achievable. This improved resolution will allow cryo-EM to make groundbreaking contributions in essential aspects of ribosome biology, including the assembly process. In this review, we summarize important insights that cryo-EM, in combination with chemical and genetic approaches, has already brought to our current understanding of the ribosomal assembly process in bacteria using previous detector technology. More importantly, we discuss how the higher resolution structures now attainable with direct electron detectors can be leveraged to propose precise testable models regarding this process. These structures will provide an effective platform to develop new antibiotics that target this fundamental cellular process. PMID:28180306

Proteome-wide Prediction of Self-interacting Proteins Based on Multiple Properties*

PubMed Central

Liu, Zhongyang; Guo, Feifei; Zhang, Jiyang; Wang, Jian; Lu, Liang; Li, Dong; He, Fuchu

2013-01-01

Self-interacting proteins, whose two or more copies can interact with each other, play important roles in cellular functions and the evolution of protein interaction networks (PINs). Knowing whether a protein can self-interact can contribute to and sometimes is crucial for the elucidation of its functions. Previous related research has mainly focused on the structures and functions of specific self-interacting proteins, whereas knowledge on their overall properties is limited. Meanwhile, the two current most common high throughput protein interaction assays have limited ability to detect self-interactions because of biological artifacts and design limitations, whereas the bioinformatic prediction method of self-interacting proteins is lacking. This study aims to systematically study and predict self-interacting proteins from an overall perspective. We find that compared with other proteins the self-interacting proteins in the structural aspect contain more domains; in the evolutionary aspect they tend to be conserved and ancient; in the functional aspect they are significantly enriched with enzyme genes, housekeeping genes, and drug targets, and in the topological aspect tend to occupy important positions in PINs. Furthermore, based on these features, after feature selection, we use logistic regression to integrate six representative features, including Gene Ontology term, domain, paralogous interactor, enzyme, model organism self-interacting protein, and betweenness centrality in the PIN, to develop a proteome-wide prediction model of self-interacting proteins. Using 5-fold cross-validation and an independent test, this model shows good performance. Finally, the prediction model is developed into a user-friendly web service SLIPPER (SeLf-Interacting Protein PrEdictoR). Users may submit a list of proteins, and then SLIPPER will return the probability_scores measuring their possibility to be self-interacting proteins and various related annotation information. This work helps us understand the role self-interacting proteins play in cellular functions from an overall perspective, and the constructed prediction model may contribute to the high throughput finding of self-interacting proteins and provide clues for elucidating their functions. PMID:23422585

Challenges in Scale-Resolving Simulations of turbulent wake flows with coherent structures

NASA Astrophysics Data System (ADS)

Pereira, Filipe S.; Eça, Luís; Vaz, Guilherme; Girimaji, Sharath S.

2018-06-01

The objective of this work is to investigate the challenges encountered in Scale-Resolving Simulations (SRS) of turbulent wake flows driven by spatially-developing coherent structures. SRS of practical interest are expressly intended for efficiently computing such flows by resolving only the most important features of the coherent structures and modelling the remainder as stochastic field. The success of SRS methods depends upon three important factors: i) ability to identify key flow mechanisms responsible for the generation of coherent structures; ii) determine the optimum range of resolution required to adequately capture key elements of coherent structures; and iii) ensure that the modelled part is comprised nearly exclusively of fully-developed stochastic turbulence. This study considers the canonical case of the flow around a circular cylinder to address the aforementioned three key issues. It is first demonstrated using experimental evidence that the vortex-shedding instability and flow-structure development involves four important stages. A series of SRS computations of progressively increasing resolution (decreasing cut-off length) are performed. An a priori basis for locating the origin of the coherent structures development is proposed and examined. The criterion is based on the fact that the coherent structures are generated by the Kelvin-Helmholtz (KH) instability. The most important finding is that the key aspects of coherent structures can be resolved only if the effective computational Reynolds number (based on total viscosity) exceeds the critical value of the KH instability in laminar flows. Finally, a quantitative criterion assessing the nature of the unresolved field based on the strain-rate ratio of mean and unresolved fields is examined. The two proposed conditions and rationale offer a quantitative basis for developing "good practice" guidelines for SRS of complex turbulent wake flows with coherent structures.

Molecular Designs for Enhancement of Polarity in Ferroelectric Soft Materials

NASA Astrophysics Data System (ADS)

Ohtani, Ryo; Nakaya, Manabu; Ohmagari, Hitomi; Nakamura, Masaaki; Ohta, Kazuchika; Lindoy, Leonard F.; Hayami, Shinya

2015-11-01

The racemic oxovanadium(IV) salmmen complexes, [VO((rac)-(4-X-salmmen))] (X = C12C10C5 (1), C16 (2), and C18 (3); salmmen = N,N‧-monomethylenebis-salicylideneimine) with “banana shaped” molecular structures were synthesized, and their ferroelectric properties were investigated. These complexes exhibit well-defined hysteresis loops in their viscous phases, moreover, 1 also displays liquid crystal behaviour. We observed a synergetic effect influenced by three structural aspects; the methyl substituents on the ethylene backbone, the banana shaped structure and the square pyramidal metal cores all play an important role in generating the observed ferroelectricity, pointing the way to a useful strategy for the creation of advanced ferroelectric soft materials.

A theoretical perspective on the accuracy of rotational resonance (R 2)-based distance measurements in solid-state NMR

NASA Astrophysics Data System (ADS)

Pandey, Manoj Kumar; Ramachandran, Ramesh

2010-03-01

The application of solid-state NMR methodology for bio-molecular structure determination requires the measurement of constraints in the form of 13C-13C and 13C-15N distances, torsion angles and, in some cases, correlation of the anisotropic interactions. Since the availability of structurally important constraints in the solid state is limited due to lack of sufficient spectral resolution, the accuracy of the measured constraints become vital in studies relating the three-dimensional structure of proteins to its biological functions. Consequently, the theoretical methods employed to quantify the experimental data become important. To accentuate this aspect, we re-examine analytical two-spin models currently employed in the estimation of 13C-13C distances based on the rotational resonance (R 2) phenomenon. Although the error bars for the estimated distances tend to be in the range 0.5-1.0 Å, R 2 experiments are routinely employed in a variety of systems ranging from simple peptides to more complex amyloidogenic proteins. In this article we address this aspect by highlighting the systematic errors introduced by analytical models employing phenomenological damping terms to describe multi-spin effects. Specifically, the spin dynamics in R 2 experiments is described using Floquet theory employing two different operator formalisms. The systematic errors introduced by the phenomenological damping terms and their limitations are elucidated in two analytical models and analysed by comparing the results with rigorous numerical simulations.

Characterising large-scale structure with the REFLEX II cluster survey

NASA Astrophysics Data System (ADS)

Chon, Gayoung

2016-10-01

We study the large-scale structure with superclusters from the REFLEX X-ray cluster survey together with cosmological N-body simulations. It is important to construct superclusters with criteria such that they are homogeneous in their properties. We lay out our theoretical concept considering future evolution of superclusters in their definition, and show that the X-ray luminosity and halo mass functions of clusters in superclusters are found to be top-heavy, different from those of clusters in the field. We also show a promising aspect of using superclusters to study the local cluster bias and mass scaling relation with simulations.

Multiscale Pores in TBCs for Lower Thermal Conductivity

NASA Astrophysics Data System (ADS)

Zhang, Wei-Wei; Li, Guang-Rong; Zhang, Qiang; Yang, Guan-Jun

2017-08-01

The morphology and pattern (including orientation and aspect ratio) of pores in thermal barrier coatings (TBCs) significantly affect their thermal insulation performance. In this work, finite element analysis was used to comprehensively understand the thermal insulation effect of pores and correlate the effective thermal conductivity with the structure. The results indicated that intersplat pores, and in particular their aspect ratio, dominantly affect the heat transfer in the top coat. The effective thermal conductivity decreased as a function of aspect ratio, since a larger aspect ratio often corresponds to a greater proportion of effective length of the pores. However, in conventional plasma-sprayed TBCs, intersplat pores often fail to maximize thermal insulation due to their distinct lower aspect ratios. Therefore, considering this effect of aspect ratio, a new structure design with multiscale pores is proposed and a corresponding structural model developed to correlate the thermal properties with this pore-rich structure. The predictions of the model are well consistent with experimental data. This study provides comprehensive understanding of the effect of pores on the thermal insulation performance, shedding light on the possibility of structural tailoring to obtain advanced TBCs with lower thermal conductivity.

Cartographic generalization of urban street networks based on gravitational field theory

NASA Astrophysics Data System (ADS)

Liu, Gang; Li, Yongshu; Li, Zheng; Guo, Jiawei

2014-05-01

The automatic generalization of urban street networks is a constant and important aspect of geographical information science. Previous studies show that the dual graph for street-street relationships more accurately reflects the overall morphological properties and importance of streets than do other methods. In this study, we construct a dual graph to represent street-street relationship and propose an approach to generalize street networks based on gravitational field theory. We retain the global structural properties and topological connectivity of an original street network and borrow from gravitational field theory to define the gravitational force between nodes. The concept of multi-order neighbors is introduced and the gravitational force is taken as the measure of the importance contribution between nodes. The importance of a node is defined as the result of the interaction between a given node and its multi-order neighbors. Degree distribution is used to evaluate the level of maintaining the global structure and topological characteristics of a street network and to illustrate the efficiency of the suggested method. Experimental results indicate that the proposed approach can be used in generalizing street networks and retaining their density characteristics, connectivity and global structure.

An Alternative to Farmer Age as an Indicator of Life-Cycle Stage: The Case for a Farm Family Age Index

ERIC Educational Resources Information Center

Burton, Rob J. F.

2006-01-01

In studies of farming, the age of the principal decision-maker (PDM) has been associated with numerous farm structural and managerial features and has been widely accepted as a good indicator of the influence of life-cycle factors on decision-making. As such, it has become an important aspect of many quantitative studies of agricultural change.…

Investigations of Flow Over a Hemisphere Using Numerical Simulations (Postprint)

DTIC Science & Technology

2015-06-22

ranging from missile defense, remote sensing , and imaging . An important aspect of these applications is determining the effective beam-on-target...Stokes (URANS), detached eddy simulation (DES), and hybrid RANS/LES. The numerical results were compared with the experiment conducted at Auburn...turret. Using the DES and hybrid RANS/LES turbulence models, Loci-Chem was able to capture the unsteady flow structures, such as the shear layer

Assessing Time Management Skills as an Important Aspect of Student Learning: The Construction and Evaluation of a Time Management Scale with Spanish High School Students

ERIC Educational Resources Information Center

Garcia-Ros, Rafael; Perez-Gonzalez, Francisco; Hinojosa, Eugenia

2004-01-01

The main purpose of this study is to analyse the factorial structure, psychometric properties and predictive capacity for academic achievement of a scale designed to evaluate the time management skills of Spanish high school students. An adaptation of the Time Management Questionnaire was presented to two samples of 350 Spanish high school…

Selected aspects of lunar mare geology from Apollo orbital photography. [of lunar craters

NASA Technical Reports Server (NTRS)

Young, R. A.; Brennan, W. J.

1976-01-01

Crater size-frequency distributions were studied (100-500 m) and are shown to provide significant integrated information concerning mare surface ages, subsurface stratigraphy, and surficial geology. Equilibrium cratering is discussed gradually reducing the relative numbers of craters smaller than 300-400 m in diameter as surfaces age and regolith thickens. Results for surface ages are in good agreement with other published crater ages. The existing correlations of large ring structures among various circular mare basins are shown to be based on criteria that are inconsistent and nonstandardized. A means of comparing equivalent ring structures in the different maria is proposed which takes into account the important characteristics of young unflooded basins (Orientale) as well as the progressive development of tectonic and volcanic features within the older flooded maria. Specific geologic aspects of several of the lunar maria are discussed and especially Mare Smythii, because of its great age and significantly different surface morphology. Lunar photographs and maps are shown.

Factor Structure of the Escala de Autoeficacia para la Depresión en Adolescentes (EADA)

PubMed Central

Díaz-Santos, Mirella; Cumba-Avilés, Eduardo; Bernal, Guillermo; Rivera-Medina, Carmen

2018-01-01

The current concept and measures of self-efficacy for depression in adolescents do not consider developmental and cultural aspects essential to understand and assess this construct in Latino youth. We examined the factor structure of the Escala de Autoeficacia para la Depresión en Adolescentes (EADA): a Spanish instrument designed to assess this construct as experienced by this population. Participants were 116 Puerto Rican adolescents aged 13 to 17 years who completed the EADA and two other self-report measures. An exploratory factor analysis yielded a two-factor solution (Personal Self-Efficacy for Depression and Interpersonal Self-Efficacy for Depression) accounting for 37.57% of the total variance. Results revealed that EADA factors have excellent internal consistency as well as concurrent and construct validity, supporting its adequacy to assess Latino adolescents’ self-efficacy for depression. The conceptual meaning of the factors was consistent with the distinction between aspects of this construct hypothesized to be important among Latino youth.

Extraversion and behavioral activation: integrating the components of approach.

PubMed

Quilty, Lena C; DeYoung, Colin G; Oakman, Jonathan M; Bagby, R Michael

2014-01-01

This investigation evaluates the structure and correlates of lower order traits related to approach, specifically, facets of extraversion and behavioral activation system (BAS) sensitivity. A 3-factor structure of approach was derived in community and clinical samples: assertiveness, enthusiasm, and sensation seeking. All factors were positively associated with Openness/Intellect scores. Enthusiasm and assertiveness were both negatively associated with Neuroticism scores, but were distinguished by associations with Agreeableness and Conscientiousness. Sensation seeking was negatively associated with Conscientiousness scores. The 3 factors demonstrated a unique profile of association with components of impulsivity. Enthusiasm and assertiveness were negatively related to psychopathological symptoms, whereas sensation seeking was largely independent of psychopathology. Results suggest that approach is associated with 3 subfactors, which differ in their pattern or magnitude of associations with other variables, thus underscoring the importance of distinguishing among them. Further, results support the construct validity of the Assertiveness and Enthusiasm aspect scales of the Big Five Aspect Scales to assess traits at this level of the personality hierarchy.

Genetics, Molecular, and Proteomics Advances in Filamentous Fungi.

PubMed

Sharma Ghimire, Prakriti; Jin, Cheng

2017-10-01

Filamentous fungi play a dynamic role in health and the environment. In addition, their unique and complex hyphal structures are involved in their morphogenesis, integrity, synthesis, and degradation, according to environmental and physiological conditions and resource availability. However, in biotechnology, it has a great value in the production of enzymes, pharmaceuticals, and food ingredients. The beginning of nomenclature of overall fungi started in early 1990 after which the categorization, interior and exterior mechanism, function, molecular and genetics study took pace. This mini-review has emphasized some of the important aspects of filamentous fungi, their pattern of life cycle, history, and development of different strategic methods applied to exploit this unique organism. New trends and concepts that have been applied to overcome obstacle because of their basic structure related to genomics and systems biology has been presented. Furthermore, the future aspects and challenges that need to be deciphered to get a bigger and better picture of filamentous fungi have been discussed.

Health and Masculinities Shaped by Agency within Structures among Young Unemployed Men in a Northern Swedish Context.

PubMed

Hammarström, Anne; Lundman, Berit; Ahlgren, Christina; Wiklund, Maria

2015-01-01

The aim of our paper was to explore expressions of life choices and life chances (aspects of agency within structures) related to power and experiences of health among early unemployed adolescent young men during the transition period to adulthood. These expressions of agency within structure were interpreted in the light of Cockerham's Health Lifestyles Theory. Furthermore, social constructions of masculinities were addressed in our analysis. Repeated interviews with ten young men in a cohort of school leavers were analyzed with qualitative content analysis. Cockerham's model was useful for interpreting our findings and we found disposition to act to be a crucial theoretical tool to capture the will and intentions of participants in relation to health. We developed the model in the following ways: structure and socialization were visualized as surrounding the whole model. Analyses of what enhances or restricts power are important. In addition to practices of health lifestyles, we added experiences of health as outcome as well as emotional aspects in disposition to act. We interpret our findings as constructions of masculinities within certain structures, in relation to choices, habitus and practices. Qualitative research could contribute to develop the understanding of the agency within structure relationships. Future studies need to pay attention to experiences of health among young people at the margin of the labor market in various milieus--and to analyze these in relation to gender constructions and within the frame-work of agency within structure.

Molecular Dynamics Methodologies for Probing Cannabinoid Ligand/Receptor Interaction

PubMed Central

Lynch, Diane L.; Hurst, Dow P.; Shore, Derek M.; Pitman, Mike C.; Reggio, Patricia H.

2018-01-01

The cannabinoid type 1 and 2 G-protein-coupled receptors are currently important pharmacological targets with significant drug discovery potential. These receptors have been shown to display functional selectivity or biased agonism, a property currently thought to have substantial therapeutic potential. Although recent advances in crystallization techniques have provided a wealth of structural information about this important class of membrane-embedded proteins, these structures lack dynamical information. In order to fully understand the interplay of structure and function for this important class of proteins, complementary techniques that address the dynamical aspects of their function are required such as NMR as well as a variety of other spectroscopies. Complimentary to these experimental approaches is molecular dynamics, which has been effectively used to help unravel, at the atomic level, the dynamics of ligand binding and activation of these membrane-bound receptors. Here, we discuss and present several representative examples of the application of molecular dynamics simulations to the understanding of the signatures of ligand-binding and -biased signaling at the cannabinoid type 1 and 2 receptors. PMID:28750815

Clark's nutcracker spatial memory: the importance of large, structural cues.

PubMed

Bednekoff, Peter A; Balda, Russell P

2014-02-01

Clark's nutcrackers, Nucifraga columbiana, cache and recover stored seeds in high alpine areas including areas where snowfall, wind, and rockslides may frequently obscure or alter cues near the cache site. Previous work in the laboratory has established that Clark's nutcrackers use spatial memory to relocate cached food. Following from aspects of this work, we performed experiments to test the importance of large, structural cues for Clark's nutcracker spatial memory. Birds were no more accurate in recovering caches when more objects were on the floor of a large experimental room nor when this room was subdivided with a set of panels. However, nutcrackers were consistently less accurate in this large room than in a small experimental room. Clark's nutcrackers probably use structural features of experimental rooms as important landmarks during recovery of cached food. This use of large, extremely stable cues may reflect the imperfect reliability of smaller, closer cues in the natural habitat of Clark's nutcrackers. This article is part of a Special Issue entitled: CO3 2013. Copyright © 2013 Elsevier B.V. All rights reserved.

Long-term variability of importance of brain regions in evolving epileptic brain networks

NASA Astrophysics Data System (ADS)

Geier, Christian; Lehnertz, Klaus

2017-04-01

We investigate the temporal and spatial variability of the importance of brain regions in evolving epileptic brain networks. We construct these networks from multiday, multichannel electroencephalographic data recorded from 17 epilepsy patients and use centrality indices to assess the importance of brain regions. Time-resolved indications of highest importance fluctuate over time to a greater or lesser extent, however, with some periodic temporal structure that can mostly be attributed to phenomena unrelated to the disease. In contrast, relevant aspects of the epileptic process contribute only marginally. Indications of highest importance also exhibit pronounced alternations between various brain regions that are of relevance for studies aiming at an improved understanding of the epileptic process with graph-theoretical approaches. Nonetheless, these findings may guide new developments for individualized diagnosis, treatment, and control.

Topology optimization aided structural design: Interpretation, computational aspects and 3D printing.

PubMed

Kazakis, Georgios; Kanellopoulos, Ioannis; Sotiropoulos, Stefanos; Lagaros, Nikos D

2017-10-01

Construction industry has a major impact on the environment that we spend most of our life. Therefore, it is important that the outcome of architectural intuition performs well and complies with the design requirements. Architects usually describe as "optimal design" their choice among a rather limited set of design alternatives, dictated by their experience and intuition. However, modern design of structures requires accounting for a great number of criteria derived from multiple disciplines, often of conflicting nature. Such criteria derived from structural engineering, eco-design, bioclimatic and acoustic performance. The resulting vast number of alternatives enhances the need for computer-aided architecture in order to increase the possibility of arriving at a more preferable solution. Therefore, the incorporation of smart, automatic tools in the design process, able to further guide designer's intuition becomes even more indispensable. The principal aim of this study is to present possibilities to integrate automatic computational techniques related to topology optimization in the phase of intuition of civil structures as part of computer aided architectural design. In this direction, different aspects of a new computer aided architectural era related to the interpretation of the optimized designs, difficulties resulted from the increased computational effort and 3D printing capabilities are covered here in.

Multi-attribute integrated measurement of node importance in complex networks.

PubMed

Wang, Shibo; Zhao, Jinlou

2015-11-01

The measure of node importance in complex networks is very important to the research of networks stability and robustness; it also can ensure the security of the whole network. Most researchers have used a single indicator to measure the networks node importance, so that the obtained measurement results only reflect certain aspects of the networks with a loss of information. Meanwhile, because of the difference of networks topology, the nodes' importance should be described by combining the character of the networks topology. Most of the existing evaluation algorithms cannot completely reflect the circumstances of complex networks, so this paper takes into account the degree of centrality, the relative closeness centrality, clustering coefficient, and topology potential and raises an integrated measuring method to measure the nodes' importance. This method can reflect nodes' internal and outside attributes and eliminate the influence of network structure on the node importance. The experiments of karate network and dolphin network show that networks topology structure integrated measure has smaller range of metrical result than a single indicator and more universal. Experiments show that attacking the North American power grid and the Internet network with the method has a faster convergence speed than other methods.

Isoquinoline alkaloids and their binding with DNA: calorimetry and thermal analysis applications.

PubMed

Bhadra, Kakali; Kumar, Gopinatha Suresh

2010-11-01

Alkaloids are a group of natural products with unmatched chemical diversity and biological relevance forming potential quality pools in drug screening. The molecular aspects of their interaction with many cellular macromolecules like DNA, RNA and proteins are being currently investigated in order to evolve the structure activity relationship. Isoquinolines constitute an important group of alkaloids. They have extensive utility in cancer therapy and a large volume of data is now emerging in the literature on their mode, mechanism and specificity of binding to DNA. Thermodynamic characterization of the binding of these alkaloids to DNA may offer key insights into the molecular aspects that drive complex formation and these data can provide valuable information about the balance of driving forces. Various thermal techniques have been conveniently used for this purpose and modern calorimetric instrumentation provides direct and quick estimation of thermodynamic parameters. Thermal melting studies and calorimetric techniques like isothermal titration calorimetry and differential scanning calorimetry have further advanced the field by providing authentic, reliable and sensitive data on various aspects of temperature dependent structural analysis of the interaction. In this review we present the application of various thermal techniques, viz. isothermal titration calorimetry, differential scanning calorimetry and optical melting studies in the characterization of drug-DNA interactions with particular emphasis on isoquinoline alkaloid-DNA interaction.

[Kidney patients: aspects related to compliance with renal treatment].

PubMed

Caraballo Nazario, G L; Lebrón de avilés, C; Dávila Torres, R R; Burgos Calderón, R

2001-12-01

The Objective of this study was identify the aspects related with the adherence of medical treatment recommended to the patients that received hemodialysis in the tertiary public hospital. A non experimental transectional correlation design was utilized in this study. Fifty-three patients constituted the population study. A structure interview was utilized to gathered the data. Descriptive statistics and Chi-square tests were utilized to analysis. The response rate was 91.0%. The 75.0% of patients not compliance with the medical treatment. Significant association between compliance variable and educational level was encountered (p < or = 0.05). This study provides important findings to will develops educative intervention in the Renal Unit, directed to improve the adherence of the patient with medical treatment.

Mechanical properties of transription

NASA Astrophysics Data System (ADS)

Sevier, Stuart; Levine, Herbert

Over the last several decades it has been increasingly recognized that both stochastic and mechanical processes play a central role in transcription. Though many aspects have been explained a number of fundamental properties are undeveloped. Recent results have pointed to mechanical feedback as the source of transcriptional bursting and DNA supercoiling but a reconciliation of this perspective with preexisting views of transcriptional is lacking. In this work we present a simple model of transcription where RNA elongation, RNA polymerase rotation and DNA supercoiling are coupled. The mechanical properties of each object form a foundational framework for understanding the physical nature of transcription. The resulting model can explain several important aspects of chromatin structure and generates a number of predictions for the mechanical properties of transcription.

Significant aspects on thermal degradation of hybrid biocomposite material

NASA Astrophysics Data System (ADS)

Bavan, D. Saravana; Kumar, G. C. Mohan

2013-06-01

Interest in use of bio fibers is increasing rapidly in structural and automotive applications because of few important properties such as low density, mechanical properties, renewability, biodegradation and sustainability. The present work is focused on fabricating a hybrid bio-composite material processed through compression molding technique. Natural fibers of maize and jute with bio polymeric resin of epoxidized soya bean oil are used as a matrix in obtaining a hybrid bio composite material. Thermal degradation of the prepared material is studied through Thermal gravimetric analyzer. Chemical treatment of the fibers was performed to have a better adhesion between the fibers and the matrix. The work is also surveyed on various parameters influencing the thermal properties and other aspects for a hybrid bio composite material.

Diversified management of coal enterprises in China: model selection, motivation and effect analysis

NASA Astrophysics Data System (ADS)

Lyu, Jingye; Lian, Xu; Li, Penglin

2018-01-01

In the context of promoting the new energy revolution and economic development of the new normal, the coal industry to excess production capacity is one of the important aspects of structural reform of the supply side. The purpose of diversification of coal enterprises in China is to seize historical opportunities, create new models of development and improve operational efficiency. In the research on diversification of coal enterprises, exploring the mode selection, motivation and effect from the aspects of the industry is conducive to the realization of the smooth replacement and the sustainable development of enterprises, to further enrich the strategic management of coal enterprises, to provide effective reference for the formulation of enterprise management decision-making and implementation of diversification strategy.

Mind-Wandering as a Natural Kind: A Family-Resemblances View.

PubMed

Seli, Paul; Kane, Michael J; Smallwood, Jonathan; Schacter, Daniel L; Maillet, David; Schooler, Jonathan W; Smilek, Daniel

2018-06-01

As empirical research on mind-wandering accelerates, we draw attention to an emerging trend in how mind-wandering is conceptualized. Previously articulated definitions of mind-wandering differ from each other in important ways, yet they also maintain overlapping characteristics. This conceptual structure suggests that mind-wandering is best considered from a family-resemblances perspective, which entails treating it as a graded, heterogeneous construct and clearly measuring and describing the specific aspect(s) of mind-wandering that researchers are investigating. We believe that adopting this family-resemblances approach will increase conceptual and methodological connections among related phenomena in the mind-wandering family and encourage a more nuanced and precise understanding of the many varieties of mind-wandering. Copyright © 2018 Elsevier Ltd. All rights reserved.

Rapid structural analysis of nanomaterials in aqueous solutions

NASA Astrophysics Data System (ADS)

Ryuzaki, Sou; Tsutsui, Makusu; He, Yuhui; Yokota, Kazumichi; Arima, Akihide; Morikawa, Takanori; Taniguchi, Masateru; Kawai, Tomoji

2017-04-01

Rapid structural analysis of nanoscale matter in a liquid environment represents innovative technologies that reveal the identities and functions of biologically important molecules. However, there is currently no method with high spatio-temporal resolution that can scan individual particles in solutions to gain structural information. Here we report the development of a nanopore platform realizing quantitative structural analysis for suspended nanomaterials in solutions with a high z-axis and xy-plane spatial resolution of 35.8 ± 1.1 and 12 nm, respectively. We used a low thickness-to-diameter aspect ratio pore architecture for achieving cross sectional areas of analyte (i.e. tomograms). Combining this with multiphysics simulation methods to translate ionic current data into tomograms, we demonstrated rapid structural analysis of single polystyrene (Pst) beads and single dumbbell-like Pst beads in aqueous solutions.

UET: a database of evolutionarily-predicted functional determinants of protein sequences that cluster as functional sites in protein structures.

PubMed

Lua, Rhonald C; Wilson, Stephen J; Konecki, Daniel M; Wilkins, Angela D; Venner, Eric; Morgan, Daniel H; Lichtarge, Olivier

2016-01-04

The structure and function of proteins underlie most aspects of biology and their mutational perturbations often cause disease. To identify the molecular determinants of function as well as targets for drugs, it is central to characterize the important residues and how they cluster to form functional sites. The Evolutionary Trace (ET) achieves this by ranking the functional and structural importance of the protein sequence positions. ET uses evolutionary distances to estimate functional distances and correlates genotype variations with those in the fitness phenotype. Thus, ET ranks are worse for sequence positions that vary among evolutionarily closer homologs but better for positions that vary mostly among distant homologs. This approach identifies functional determinants, predicts function, guides the mutational redesign of functional and allosteric specificity, and interprets the action of coding sequence variations in proteins, people and populations. Now, the UET database offers pre-computed ET analyses for the protein structure databank, and on-the-fly analysis of any protein sequence. A web interface retrieves ET rankings of sequence positions and maps results to a structure to identify functionally important regions. This UET database integrates several ways of viewing the results on the protein sequence or structure and can be found at http://mammoth.bcm.tmc.edu/uet/. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

Radiolysis aspects of the aqueous self-cooled blanket concept and the problem of tritium extraction

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

Bruggeman, A.; Snykers, M.; DeRegge, P.

1988-09-01

In the Aqueous Self-Cooled Blanket (ASCB) concept, an aqueous /sup 6/Li solution in a metallic structure is used as a fusion reactor shielding-breeding blanket. Radiolysis effects could be very important for the design and the use of an ASCB. Although many aspects of the radiation chemistry of water and dilute aqueous solutions are now reasonably well understood, it is not possible to predict the radiochemical behaviour of the concentrated candidate ASCB solutions quantitatively. However, by means of a worst case calculation for a possible ASCB for the Next European Torus (NET) it is shown that even with an important ratemore » of water decomposition the ASCB concept is still workable. Gas bubbles and explosive mixtures can be avoided by increasing the pressure in the neutron irradiated zone and by extracting and/or recombining the radiolytically produced hydrogen and oxygen. This could require an additional inert gas loop, which could also be used as part of the tritium extraction installation.« less

An analysis of the influence of framework aspects on the study design of health economic modeling evaluations.

PubMed

Gurtner, Sebastian

2013-04-01

Research and practical guidelines have many implications for how to structure a health economic study. A major focus in recent decades has been the quality of health economic research. In practice, the factors influencing a study design are not limited to the quest for quality. Moreover, the framework of the study is important. This research addresses three major questions related to these framework aspects. First, we want to know whether the design of health economic studies has changed over time. Second, we want to know how the subject of a study, whether it is a process or product innovation, influences the parameters of the study design. Third, one of the most important questions we will answer is whether and how the study's source of funding has an impact on the design of the research. To answer these questions, a total of 234 health economic studies were analyzed using a correspondence analysis and a logistic regression analysis. All three categories of framework factors have an influence on the aspects of the study design. Health economic studies have evolved over time, leading to the use of more advanced methods like complex sensitivity analyses. Additionally, the patient's point of view has increased in importance. The evaluation of product innovations has focused more on utility concepts. On the other hand, the source of funding may influence only a few aspects of the study design, such as the use of evaluation methods, the source of data, and the use of certain utility measures. The most important trends in health care, such as the emphasis on the patients' point of view, become increasingly established in health economic evaluations with the passage of time. Although methodological challenges remain, modern information and communication technologies provide a basis for increasing the complexity and quality of health economic studies if used frequently.

Indirect effects in community ecology: Their definition, study and importance.

PubMed

Strauss, S Y

1991-07-01

The diversity of indirect interactions that can occur within communities is large. Recent research on indirect interactions is scattered in the literature under numerous labels. The definition of indirect effects is an important aspect of their study, and clarifies some of the subtle differences among indirect effects found in natural communities. Choosing which species to study, how to manipulate species and for what duration, which attributes to measure and, finally, which analytical techniques to use are all problems facing the community ecologist. Ultimately, we are striving for the best means of determining the relative importance of direct and indirect effects in structuring communities. Copyright © 1991. Published by Elsevier Ltd.

Evidence of active region imprints on the solar wind structure

NASA Technical Reports Server (NTRS)

Hick, P.; Jackson, B. V.

1995-01-01

A common descriptive framework for discussing the solar wind structure in the inner heliosphere uses the global magnetic field as a reference: low density, high velocity solar wind emanates from open magnetic fields, with high density, low speed solar wind flowing outward near the current sheet. In this picture, active regions, underlying closed magnetic field structures in the streamer belt, leave little or no imprint on the solar wind. We present evidence from interplanetary scintillation measurements of the 'disturbance factor' g that active regions play a role in modulating the solar wind and possibly contribute to the solar wind mass output. Hence we find that the traditional view of the solar wind, though useful in understanding many features of solar wind structure, is oversimplified and possibly neglects important aspects of solar wind dynamics

Theoretical Aspects of Laser-Induced Periodic Surface Structure Formation,

DTIC Science & Technology

1983-11-01

r AD-A134 875 UNCLASSIFIED THEORETICAL ASPECTS OF LASER -INUUCtl) PtKlUUlt bUKhALt STRUCTURE FORMATION(U) ROCHESTER UNIV NY DEPT OF CHEMISTRY M...UR0CHESTER/DC/83/TR-43 2. COVT ACCESSION NO A. TITLE (and Subllllm) Theoretical Aspects of Laser -Induced Periodic Surface Structure Formation 7...publication in Laser -Controlled Chemical Processing of Surfaces, ed. by A. W. Johnson and D. J. Ehrlich (Elsevier, New York) 19 KEY WORDS (Continue

Acicular photomultiplier photocathode structure

DOEpatents

Craig, Richard A.; Bliss, Mary

2003-09-30

A method and apparatus for increasing the quantum efficiency of a photomultiplier tube by providing a photocathode with an increased surface-to-volume ratio. The photocathode includes a transparent substrate, upon one major side of which is formed one or more large aspect-ratio structures, such as needles, cones, fibers, prisms, or pyramids. The large aspect-ratio structures are at least partially composed of a photoelectron emitting material, i.e., a material that emits a photoelectron upon absorption of an optical photon. The large aspect-ratio structures may be substantially composed of the photoelectron emitting material (i.e., formed as such upon the surface of a relatively flat substrate) or be only partially composed of a photoelectron emitting material (i.e., the photoelectron emitting material is coated over large aspect-ratio structures formed from the substrate material itself.) The large aspect-ratio nature of the photocathode surface allows for an effective increase in the thickness of the photocathode relative the absorption of optical photons, thereby increasing the absorption rate of incident photons, without substantially increasing the effective thickness of the photocathode relative the escape incidence of the photoelectrons.

Using NMR chemical shifts to calculate the propensity for structural order and disorder in proteins.

PubMed

Tamiola, Kamil; Mulder, Frans A A

2012-10-01

NMR spectroscopy offers the unique possibility to relate the structural propensities of disordered proteins and loop segments of folded peptides to biological function and aggregation behaviour. Backbone chemical shifts are ideally suited for this task, provided that appropriate reference data are available and idiosyncratic sensitivity of backbone chemical shifts to structural information is treated in a sensible manner. In the present paper, we describe methods to detect structural protein changes from chemical shifts, and present an online tool [ncSPC (neighbour-corrected Structural Propensity Calculator)], which unites aspects of several current approaches. Examples of structural propensity calculations are given for two well-characterized systems, namely the binding of α-synuclein to micelles and light activation of photoactive yellow protein. These examples spotlight the great power of NMR chemical shift analysis for the quantitative assessment of protein disorder at the atomic level, and further our understanding of biologically important problems.

Effect of Fin Porosity on Wake Geometry for Flapping Fins at Intermediate Reynolds Number

NASA Astrophysics Data System (ADS)

Chen, J.; Xia, B.; Krueger, P. S.

2017-11-01

Low aspect ratio flapping fins generate interesting 3-dimensional flow structures as has been observed, for example, in studies of fish swimming. As the Reynolds number is reduced, the exact geometry of the fin is less important and even certain amounts of porosity might be allowed without significantly affecting propulsive performance. These effects are investigated experimentally using flapping rectangular fins of aspect ratio 2 at Reynolds numbers in the range 100 - 1000. The experiments were conducted using a water tunnel to supply the free stream flow and the fin flapping parameters were set to provide a Strouhal number (based on amplitude of the fin tip motion) in the range 0.15 - 0.35. Phase-averaged measurements were made of the 3-dimensional, volumetric flow field, allowing visualization of the typical shed vortex structure behind the fin and calculation of time averaged thrust and propulsive efficiency. Results comparing the flow structure in the fin wake and the resulting propulsive performance will be presented for several fins with different planform porosities where the porosities are set using arrays of holes in the fins. This material is based on the work supported by the National Science Foundation under Grant No. 1510707.

Large-eddy-simulation approach in understanding flow structures of 2D turbulent density currents over sloping surfaces

NASA Astrophysics Data System (ADS)

Nayamatullah, M.; Rao Pillalamarri, Narasimha; Bhaganagar, Kiran

2018-04-01

A numerical investigation was performed to understand the flow dynamics of 2D density currents over sloping surfaces. Large eddy simulation was conducted for lock-exchange (L-E) release currents and overflows. 2D Navier-Stokes equations were solved using the Boussinesq approximation. The effects of the lock aspect-ratio (height/length of lock), slope, and Reynolds number on the flow structures and turbulence mixing have been analyzed. Results have confirmed buoyancy within the head of the two-dimensional currents is not conserved which contradicts the classical thermal theory. The lock aspect-ratio dictates the fraction of initial buoyancy which is carried by the head of the current at the beginning of the slumping (horizontal) and accelerating phase (over a slope), which has important implications on turbulence kinetic energy production, and hence mixing in the current. For L-E flows over a slope, increasing slope angle enhances the turbulence production. Increasing slope results in shear reversal within the density current resulting in shear-instabilities. Differences in turbulence production mechanisms and flow structures exist between the L-E and constant-flux release currents resulting in significant differences in the flow characteristics between different releases.

Advanced structural optimization of a heliostat with cantilever arms

NASA Astrophysics Data System (ADS)

Bogdanov, Dimitar; Zlatanov, Hristo

2016-05-01

The weight of the support structure of heliostats, CPV and PV trackers is important cost element of a solar plant and reducing it will improve the economic viability of a solar project. Heliostats with rectangular area (1 to 5 in 1 m² steps; 5 to 150 in 5 m² steps) and aspect ratios (0.5, 1.0, 1.2, 1.5, 2.0) were investigated under various winds speeds (0, 5 to 100 in 5 m/s steps), wind direction (0 to 180° in 15° steps) and elevation positions (0 to 90° in 10° steps). Each load case was run with three different cantilever arms. The inclination angle of the chords and bracings was chosen so as to fulfill the geometrical boundary condition. Stress and buckling validations were performed according to Eurocode. The results of research carried out can be used to determine the specific weight of a heliostat in kg/m² as a function of the wind speed, tracker area and tracker aspect ratio. Future work should investigate the impact of using cold formed structural hollow sections and cross sections with thinner wall thickness which is not part of EN 10210.

Important aspects of participation and participation restrictions in people with a mild intellectual disability.

PubMed

Arvidsson, Patrik; Granlund, Mats; Thyberg, Ingrid; Thyberg, Mikael

2014-01-01

This study explored a possibility to assess the concepts of participation and participation restrictions in the International Classification of Functioning, Disability and Health (ICF) by combining self-ratings of the perceived importance with the actual performance of different everyday activities in people with a mild intellectual disability. Structured interviews regarding 68 items from the ICF activity/participation domain were conducted (n = 69). The items were ranked by perceived importance, performance and by combined measures. Furthermore, the measures were related to a single question about subjective general well-being. Rankings of performance highlighted about the same items as "important participation", while rankings of low performance addressed quite different items compared with "important participation restriction". Significant correlations were found between subjective general well-being and high performance (r = 0.56), high performance/high importance (important participation) (r = 0.56), low performance (r = -0.56) and low performance/high importance (important participation restriction; r = -0.55). The results support the clinical relevance of the ICF and the studied selection of 68 items. Although performance only may sometimes be a relevant aspect, knowledge about the relationship between the perceived importance and the actual performance is essential for clinical interventions and for research aiming to understand specific needs regarding participation. The concepts of participation and participation restriction are highly relevant in people with a mild intellectual disability. Self-rated performance might be sufficient to assess participation at a group level. In clinical practices, the relationship between the perceived importance and the actual performance of an activity is essential to assess.

A small perturbation based optimization approach for the frequency placement of high aspect ratio wings

NASA Astrophysics Data System (ADS)

Goltsch, Mandy

Design denotes the transformation of an identified need to its physical embodiment in a traditionally iterative approach of trial and error. Conceptual design plays a prominent role but an almost infinite number of possible solutions at the outset of design necessitates fast evaluations. The corresponding practice of empirical equations and low fidelity analyses becomes obsolete in the light of novel concepts. Ever increasing system complexity and resource scarcity mandate new approaches to adequately capture system characteristics. Contemporary concerns in atmospheric science and homeland security created an operational need for unconventional configurations. Unmanned long endurance flight at high altitudes offers a unique showcase for the exploration of new design spaces and the incidental deficit of conceptual modeling and simulation capabilities. Structural and aerodynamic performance requirements necessitate light weight materials and high aspect ratio wings resulting in distinct structural and aeroelastic response characteristics that stand in close correlation with natural vibration modes. The present research effort evolves around the development of an efficient and accurate optimization algorithm for high aspect ratio wings subject to natural frequency constraints. Foundational corner stones are beam dimensional reduction and modal perturbation redesign. Local and global analyses inherent to the former suggest corresponding levels of local and global optimization. The present approach departs from this suggestion. It introduces local level surrogate models to capacitate a methodology that consists of multi level analyses feeding into a single level optimization. The innovative heart of the new algorithm originates in small perturbation theory. A sequence of small perturbation solutions allows the optimizer to make incremental movements within the design space. It enables a directed search that is free of costly gradients. System matrices are decomposed based on a Timoshenko stiffness effect separation. The formulation of respective linear changes falls back on surrogate models that approximate cross sectional properties. Corresponding functional responses are readily available. Their direct use by the small perturbation based optimizer ensures constitutive laws and eliminates a previously necessary optimization at the local level. The scope of the present work is derived from an existing configuration such as a conceptual baseline or a prototype that experiences aeroelastic instabilities. Due to the lack of respective design studies in the traditional design process it is not uncommon for an initial wing design to have such stability problems. The developed optimization scheme allows the effective redesign of high aspect ratio wings subject to natural frequency objectives. Its successful application is demonstrated by three separate optimization studies. The implementation results of all three studies confirm that the gradient liberation of the new methodology brings about great computational savings. A generic wing study is used to indicate the connection between the proposed methodology and the aeroelastic stability problems outlined in the motivation. It is also used to illustrate an important practical aspect of structural redesign, i.e., a minimum departure from the existing baseline configuration. The proposed optimization scheme is naturally conducive to this practical aspect by using a minimum change optimization criterion. However, only an elemental formulation truly enables a minimum change solution. It accounts for the spanwise significance of a structural modification to the mode of interest. This idea of localized reinforcement greatly benefits the practical realization of structural redesign efforts. The implementation results also highlight the fundamental limitation of the proposed methodology. The exclusive consideration of mass and stiffness effects on modal response characteristics disregards other disciplinary problems such as allowable stresses or buckling loads. Both are of central importance to the structural integrity of an aircraft but are currently not accounted for in the proposed optimization scheme. The concluding discussion thus outlines the need for respective constraints and/or additional analyses to capture all requirements necessary for a comprehensive structural redesign study.

Crucial contextual attributes of nursing leadership towards a care ethics.

PubMed

Gustafsson, Lena-Karin; Stenberg, Maja

2017-06-01

It is of importance to understand and communicate caring ethics as a ground for qualitative caring environments. Research is needed on nursing attributes that are visible in nursing leadership since it may give bases for reflections related to the patterns of specific contexts. The aim of this study was to illuminate the meaning of crucial attributes in nursing leadership toward an ethical care of patients in psychiatric in-patient settings. The design of the study was descriptive and qualitative with a phenomenological hermeneutical approach. Participants and research context: The study comprised focus group interviews with nurses working in indoor psychiatric care who participated after giving informed consent. Ethical considerations: Since the topic and informants are not labeled as sensitive and subject to ethical approval, it is not covered by the ethics committee's aim and purpose according to Swedish law. However, careful procedures have been followed according to ethics expressed in the Declaration of Helsinki. When identifying the thematic structures, analysis resulted in three major themes: To supply, including the following aspects: to supply evidence, to supply common space, and to supply good structures; To support, including the following aspects: to be a role model, to show appreciation and care, and to harbor; To shield, including the following aspects: to advocate, to emit non-tolerance of unethical behavior, and to reprove. Leadership is challenging for nurses and plays an important role in ethical qualitative care. These findings should not be understood as a description about nurse manager's role, which probably has different attributes and more focus on an organizational level. Making the understanding about crucial attributes explicit, the nurse may receive confirmation and recognition of crucial attributes for ethical care in order to move toward an ethical care.

Second Workshop on the European Geotraverse

NASA Astrophysics Data System (ADS)

Galson, D. A.; Müller, S.; Munsch, B.

The Second Workshop on the European Geotraverse (EGT) Project (Eos, July 19, 1983, p. 458; March 5, 1985, p. 112) was held February 7-9, 1985, at the Venetian Institute of Science, Letters, and Arts, Venice, Italy, and was organized by C. Morelli (Institute of Mining and Applied Geophysics, University of Trieste, Italy) with support from both the Secretariat of the European Science Foundation (ESF) in Strasbourg, France, and the Scientific Coordinating Committee (SCC) for the EGT Project. The workshop focused on the Southern Segment of the EGT (EGT-S), which encompasses the Central, Southern, and Western Alps, the Po Basin, the Northern Apennines, the Ligurian and Tyrrhenian Seas, Corsica and Sardinia, the Sardinian and Sicilian Channels, and the complex geological structures of Tunisia. About 100 earth scientists, from Austria (1 representative), Belgium (1), Denmark (2), the Federal Republic of Germany (7), France (10), Italy (52), The Netherlands (3), Spain (1), Switzerland (9), Tunisia (6), and the United Kingdom (4), assembled to present and discuss new geological and geophysical data in order to obtain a better understanding of the structure, dynamics, and evolution of the lithosphere in this part of the world and to identify areas where and problems on which further work is needed. A particularly important aspect of the workshop was the presentation of data and results from the EGT-S 1983 field program, which was primarily a large-scale land and sea seismic refraction survey that extended from the Southern Alps to southern Sardinia. Another important aspect was preparation for the EGT-S 1985 field program, which will be a southward extension of the 1983 program to southern Tunisia. The workshop was divided into seven sessions, during which 42 scientific papers were given dealing with various aspects of the regional geophysics, geology, and tectonics.

Automatically extracting the significant aspects evaluated in game reviews

NASA Astrophysics Data System (ADS)

Fong, Chiok Hoong; Ng, Yen Kaow

2017-04-01

Understanding the criteria (or "aspects") that reviewers use to evaluate games is important to game developers and publishers, since this will give them important input on how to improve their products. Techniques for the extraction of such aspects have been studied by others, albeit not specific to the gaming industry. In this paper we demonstrate an aspect extraction and analysis system specific to computer games. The system extracts game review texts from a list of known websites and automatically extracts candidate aspects from the review text using techniques from natural language processing and sentiment analysis. It then ranks the candidate aspects using the HITS algorithm. To evaluate the correctness of the extracted aspects, we used the system to calculate an overall score for each game by aggregating its highly-rated aspects, weighted by the importance of the respective aspects. The aggregated scores resulted in a ranking of games, which we compared to a known ranking from a popular website - the rankings showed overall consistency, which suggests that the system has extracted valuable aspects from the reviews. Using the extracted aspect, our system also facilitates the analysis of a game, by evaluating how review articles have rated its performance in these extracted aspects.

Expertise among professional magicians: an interview study.

PubMed

Rissanen, Olli; Pitkänen, Petteri; Juvonen, Antti; Kuhn, Gustav; Hakkarainen, Kai

2014-01-01

The purpose of the present investigation was to analyse interviews of highly regarded Finnish magicians. Social network analysis (N = 120) was used to identify Finland's most highly regarded magicians (N = 16). The selected participants' careers in professional magic and various aspects of their professional conduct were examined by relying on semi-structured interviews. The results revealed that cultivation of professional level competence in magic usually requires an extensive period of time compared with other domains of expertise. Magic is a unique performing art and it differs from other professions focusing on deceiving the audience. A distinctive feature of magical expertise is that the process takes place entirely through informal training supported by communities of magical practitioners. Three interrelated aspects of magical activity were distinguished: magic tricks, performance, and audience. Although magic tricks constitute a central aspect of magic activity, the participants did not talk about their tricks extensively; this is in accordance with the secretive nature of magic culture. The interviews revealed that a core aspect of the magicians' activity is performance in front of an audience that repeatedly validates competence cultivated through years of practice. The interviewees reported investing a great deal of effort in planning, orchestrating, and reflecting on their performances. Close interaction with the audience plays an important role in most interviewees' activity. Many participants put a great deal of effort in developing novel magic tricks. It is common to borrow magic effects from fellow magicians and develop novel methods of implementation. Because magic tricks or programs are not copyrighted, many interviewees considered "stealing" an unacceptable and unethical aspect of magical activity. The interviewees highlighted the importance of personality and charisma in the successful pursuit of magic activity.

Expertise among professional magicians: an interview study

PubMed Central

Rissanen, Olli; Pitkänen, Petteri; Juvonen, Antti; Kuhn, Gustav; Hakkarainen, Kai

2014-01-01

The purpose of the present investigation was to analyse interviews of highly regarded Finnish magicians. Social network analysis (N = 120) was used to identify Finland's most highly regarded magicians (N = 16). The selected participants' careers in professional magic and various aspects of their professional conduct were examined by relying on semi-structured interviews. The results revealed that cultivation of professional level competence in magic usually requires an extensive period of time compared with other domains of expertise. Magic is a unique performing art and it differs from other professions focusing on deceiving the audience. A distinctive feature of magical expertise is that the process takes place entirely through informal training supported by communities of magical practitioners. Three interrelated aspects of magical activity were distinguished: magic tricks, performance, and audience. Although magic tricks constitute a central aspect of magic activity, the participants did not talk about their tricks extensively; this is in accordance with the secretive nature of magic culture. The interviews revealed that a core aspect of the magicians' activity is performance in front of an audience that repeatedly validates competence cultivated through years of practice. The interviewees reported investing a great deal of effort in planning, orchestrating, and reflecting on their performances. Close interaction with the audience plays an important role in most interviewees' activity. Many participants put a great deal of effort in developing novel magic tricks. It is common to borrow magic effects from fellow magicians and develop novel methods of implementation. Because magic tricks or programs are not copyrighted, many interviewees considered “stealing” an unacceptable and unethical aspect of magical activity. The interviewees highlighted the importance of personality and charisma in the successful pursuit of magic activity. PMID:25566156

Struggling Towards Space Doctrine: U.S. Military Space Plans, Programs, and Perspectives During the Cold War

DTIC Science & Technology

1994-05-01

emphasizes the psychological aspects of the communal structures in which paradigms are developed and shift (thus science is what scientists say that...conduct military affairs." Imre Lakatos, by contrast, takes a less tautological and psychological approach to the process by which knowledge might...space age. An October 1950 RAND report highlighted the importance of the psychological impact which the first satellite would have on the public

Towards aspect-oriented functional--structural plant modelling.

PubMed

Cieslak, Mikolaj; Seleznyova, Alla N; Prusinkiewicz, Przemyslaw; Hanan, Jim

2011-10-01

Functional-structural plant models (FSPMs) are used to integrate knowledge and test hypotheses of plant behaviour, and to aid in the development of decision support systems. A significant amount of effort is being put into providing a sound methodology for building them. Standard techniques, such as procedural or object-oriented programming, are not suited for clearly separating aspects of plant function that criss-cross between different components of plant structure, which makes it difficult to reuse and share their implementations. The aim of this paper is to present an aspect-oriented programming approach that helps to overcome this difficulty. The L-system-based plant modelling language L+C was used to develop an aspect-oriented approach to plant modelling based on multi-modules. Each element of the plant structure was represented by a sequence of L-system modules (rather than a single module), with each module representing an aspect of the element's function. Separate sets of productions were used for modelling each aspect, with context-sensitive rules facilitated by local lists of modules to consider/ignore. Aspect weaving or communication between aspects was made possible through the use of pseudo-L-systems, where the strict-predecessor of a production rule was specified as a multi-module. The new approach was used to integrate previously modelled aspects of carbon dynamics, apical dominance and biomechanics with a model of a developing kiwifruit shoot. These aspects were specified independently and their implementation was based on source code provided by the original authors without major changes. This new aspect-oriented approach to plant modelling is well suited for studying complex phenomena in plant science, because it can be used to integrate separate models of individual aspects of plant development and function, both previously constructed and new, into clearly organized, comprehensive FSPMs. In a future work, this approach could be further extended into an aspect-oriented programming language for FSPMs.

Towards aspect-oriented functional–structural plant modelling

PubMed Central

Cieslak, Mikolaj; Seleznyova, Alla N.; Prusinkiewicz, Przemyslaw; Hanan, Jim

2011-01-01

Background and Aims Functional–structural plant models (FSPMs) are used to integrate knowledge and test hypotheses of plant behaviour, and to aid in the development of decision support systems. A significant amount of effort is being put into providing a sound methodology for building them. Standard techniques, such as procedural or object-oriented programming, are not suited for clearly separating aspects of plant function that criss-cross between different components of plant structure, which makes it difficult to reuse and share their implementations. The aim of this paper is to present an aspect-oriented programming approach that helps to overcome this difficulty. Methods The L-system-based plant modelling language L+C was used to develop an aspect-oriented approach to plant modelling based on multi-modules. Each element of the plant structure was represented by a sequence of L-system modules (rather than a single module), with each module representing an aspect of the element's function. Separate sets of productions were used for modelling each aspect, with context-sensitive rules facilitated by local lists of modules to consider/ignore. Aspect weaving or communication between aspects was made possible through the use of pseudo-L-systems, where the strict-predecessor of a production rule was specified as a multi-module. Key Results The new approach was used to integrate previously modelled aspects of carbon dynamics, apical dominance and biomechanics with a model of a developing kiwifruit shoot. These aspects were specified independently and their implementation was based on source code provided by the original authors without major changes. Conclusions This new aspect-oriented approach to plant modelling is well suited for studying complex phenomena in plant science, because it can be used to integrate separate models of individual aspects of plant development and function, both previously constructed and new, into clearly organized, comprehensive FSPMs. In a future work, this approach could be further extended into an aspect-oriented programming language for FSPMs. PMID:21724653

Computational analysis of nanofluids: A review

NASA Astrophysics Data System (ADS)

Qureshi, M. Zubair Akbar; Ashraf, Muhammad

2018-02-01

Nanofluids and heat transfer enhancement in real systems continue to be a widely research area of nanotechnology. An effort has been made to give a comprehensive review on time-wise development from different aspects of the nanofluids. The exceptional structures of nanofluids, for example, dispersion of nanoparticles volume fraction, thermophoresis phenomenon, Brownian motion, improvement in thermal conductivity, and especially heat transfer enhancement, etc., have been addressed in a mathematical perspective. The influence of important parameters like particle's (loading, material, size and shape-factor), base fluids type, temperature, additives, clustering and p H value has been considered. In addition, the summary-chart is presented for a better understanding of the mathematical structure of the Newtonian as well as non-Newtonian nanofluids. Some important results have been discussed for future work. This review article will be helpful for scientists and researchers.

Instruments to assess patients with rotator cuff pathology: a systematic review of measurement properties.

PubMed

Longo, Umile Giuseppe; Saris, Daniël; Poolman, Rudolf W; Berton, Alessandra; Denaro, Vincenzo

2012-10-01

The aims of this study were to obtain an overview of the methodological quality of studies on the measurement properties of rotator cuff questionnaires and to describe how well various aspects of the design and statistical analyses of studies on measurement properties are performed. A systematic review of published studies on the measurement properties of rotator cuff questionnaires was performed. Two investigators independently rated the quality of the studies using the Consensus-based Standards for the selection of health Measurement Instruments checklist. This checklist was developed in an international Delphi consensus study. Sixteen studies were included, in which two measurement instruments were evaluated, namely the Western Ontario Rotator Cuff Index and the Rotator Cuff Quality-of-Life Measure. The methodological quality of the included studies was adequate on some properties (construct validity, reliability, responsiveness, internal consistency, and translation) but need to be improved on other aspects. The most important methodological aspects that need to be developed are as follows: measurement error, content validity, structural validity, cross-cultural validity, criterion validity, and interpretability. Considering the importance of adequate measurement properties, it is concluded that, in the field of rotator cuff pathology, there is room for improvement in the methodological quality of studies measurement properties. II.

Film and television in Croatia today: production, new technologies and the relationship with visual anthropology.

PubMed

Svilicić, Niksa; Vidacković, Zlatko

2013-03-01

This paper seeks to explain some of the most important recent production and technological changes that have affected the relationship between television and film, especially in Croatia, from the aspect of the development of visual anthropology. In the production segment, special attention was given to the role of Croatian television stations in the production of movies, "splitting" the movies into mini-series, interrupting movies with commercial breaks, and to television movies turned into feature films. This paper tries to perceive and define the structure of methodical processes of visual anthropology (reactive process). The development of photographic and film technology and the events which led to the rapid development of visual culture also point to the inseparable duality of observing visual anthropology within reactive and proactive processes, which are indirectly closely related to the technical aspects of these processes. Defining the technical aspect of visual anthropology as such "service" necessarily interferes with the author's approach in the domain of the script and direction related procedures during pre-production, on the field and during post-production of the movie. The author's approach is important because in dependence on it, the desired spectrum of information "output", susceptible to subsequent scientific analysis, is achieved. Lastly, another important segment is the "distributive-technological process" because, regardless of the approach to the anthropologically relevant phenomenon which is being dealt with in an audio-visual piece of work, it is essential that the work be presented and viewed adequately.

Framework to model neutral particle flux in convex high aspect ratio structures using one-dimensional radiosity

NASA Astrophysics Data System (ADS)

Manstetten, Paul; Filipovic, Lado; Hössinger, Andreas; Weinbub, Josef; Selberherr, Siegfried

2017-02-01

We present a computationally efficient framework to compute the neutral flux in high aspect ratio structures during three-dimensional plasma etching simulations. The framework is based on a one-dimensional radiosity approach and is applicable to simulations of convex rotationally symmetric holes and convex symmetric trenches with a constant cross-section. The framework is intended to replace the full three-dimensional simulation step required to calculate the neutral flux during plasma etching simulations. Especially for high aspect ratio structures, the computational effort, required to perform the full three-dimensional simulation of the neutral flux at the desired spatial resolution, conflicts with practical simulation time constraints. Our results are in agreement with those obtained by three-dimensional Monte Carlo based ray tracing simulations for various aspect ratios and convex geometries. With this framework we present a comprehensive analysis of the influence of the geometrical properties of high aspect ratio structures as well as of the particle sticking probability on the neutral particle flux.

Affect Consciousness in children with internalizing problems: Assessment of affect integration.

PubMed

Taarvig, Eva; Solbakken, Ole André; Grova, Bjørg; Monsen, Jon T

2015-10-01

Affect integration was operationalized through the Affect Consciousness (AC) construct as degrees of awareness, tolerance, nonverbal expression and conceptual expression of 11 affects. These aspects are assessed through a semi-structured Affect Consciousness Interview (ACI) and separate rating scales (Affect Consciousness Scales (ACSs)) developed for use in research and clinical work with adults with psychopathological disorders. Age-adjusted changes were made in the interview and rating system. This study explored the applicability of the adjusted ACI to a sample of 11-year-old children with internalizing problems through examining inter-rater reliability of the adjusted ACI, along with relationships between the AC aspects and aspects of mental health as symptoms of depression, symptoms of anxiety, social competence, besides general intelligence. Satisfactory inter-rater reliability was found, as well as consistent relationships between the AC aspects and the various aspects of mental health, a finding which coincides with previous research. The finding indicates that the attainment of the capacity to deal adaptively with affect is probably an important contributor to the development of adequate social competence and maybe in the prevention of psychopathology in children. The results indicate that the adjusted ACI and rating scales are useful tools in treatment planning with children at least from the age of 11 years. © The Author(s) 2014.

Mobility balance in the light-emitting layer governs the polaron accumulation and operational stability of organic light-emitting diodes

NASA Astrophysics Data System (ADS)

Kim, Jae-Min; Lee, Chang-Heon; Kim, Jang-Joo

2017-11-01

Organic light-emitting diode (OLED) displays are lighter and more flexible, have a wider color gamut, and consume less power than conventional displays. Stable materials and the structural design of the device are important for OLED longevity. Control of charge transport and accumulation in the device is particularly important because the interaction of excitons and polarons results in material degradation. This research investigated the charge dynamics of OLEDs experimentally and by drift-diffusion modeling. Parallel capacitance-voltage measurements of devices provided knowledge of charge behavior at different driving voltages. A comparison of exciplex-forming co-host and single host structures established that the mobility balance in the emitting layers determined the amount of accumulated polarons in those layers. Consequently, an exciplex-forming co-host provides a superior structure in terms of device lifetime and efficiency because of its well-balanced mobility. Minimizing polaron accumulation is key to achieving long OLED device lifetimes. This is a crucial aspect of device physics that must be considered in the device design structure.

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

Hu, Enyuan; Wang, Xuelong; Yu, Xiqian

The rechargeable lithium-ion battery (LIB) is the most promising energy storage system to power electric vehicles with high energy density and long cycling life. However, in order to meet customers’ demands for fast charging, the power performances of current LIBs need to be improved. From the cathode aspect, layer-structured cathode materials are widely used in today’s market and will continue to play important roles in the near future. The high rate capability of layered cathode materials during charging and discharging is critical to the power performance of the whole cell and the thermal stability is closely related to the safetymore » issues. Therefore, the in-depth understanding of structural changes of layered cathode materials during high rate charging/discharging and the thermal stability during heating are essential in developing new materials and improving current materials. Since structural changes take place from the atomic level to the whole electrode level, combination of characterization techniques covering multilength scales is quite important. Finally, in many cases, this means using comprehensive tools involving diffraction, spectroscopy, and imaging to differentiate the surface from the bulk and to obtain structural/chemical information with different levels of spatial resolution.« less

Chemical control of orbital polarization in artificially structured transition-metal oxides: La2NiXO6 (X=B,Al,Ga,In) from first principles

NASA Astrophysics Data System (ADS)

Han, M. J.; Marianetti, C. A.; Millis, A. J.

2010-10-01

The application of modern layer-by-layer growth techniques to transition-metal oxide materials raises the possibility of creating new classes of materials with rationally designed correlated electron properties. An important step toward this goal is the demonstration that electronic structure can be controlled by atomic composition. In compounds with partially occupied transition-metal d shells, one important aspect of the electronic structure is the relative occupancy of different d orbitals. Previous work has established that strain and quantum confinement can be used to influence orbital occupancy. In this paper we demonstrate a different modality for orbital control in transition-metal oxide heterostructures, using density-functional band calculations supplemented by a tight-binding analysis to show that the choice of nontransition-metal counterion X in transition-metal oxide heterostructures composed of alternating LaNiO3 and LaXO3 units strongly affects orbital occupancy, changing the magnitude and in some cases the sign of the orbital polarization.

Mysticism and schizophrenia: A phenomenological exploration of the structure of consciousness in the schizophrenia spectrum disorders.

PubMed

Parnas, Josef; Henriksen, Mads Gram

2016-07-01

Mysticism and schizophrenia are different categories of human existence and experience. Nonetheless, they exhibit important phenomenological affinities, which, however, remain largely unaddressed. In this study, we explore structural analogies between key features of mysticism and major clinical-phenomenological aspects of the schizophrenia spectrum disorders-i.e. attitudes, the nature of experience, and the 'other', mystical or psychotic reality. Not only do these features gravitate around the issue of the basic dimensions of consciousness, they crucially seem to implicate and presuppose a specific alteration of the very structure of consciousness. This finding has bearings for the understanding of consciousness and its psychopathological distortions. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

A combined representation method for use in band structure calculations. 1: Method

NASA Technical Reports Server (NTRS)

Friedli, C.; Ashcroft, N. W.

1975-01-01

A representation was described whose basis levels combine the important physical aspects of a finite set of plane waves with those of a set of Bloch tight-binding levels. The chosen combination has a particularly simple dependence on the wave vector within the Brillouin Zone, and its use in reducing the standard one-electron band structure problem to the usual secular equation has the advantage that the lattice sums involved in the calculation of the matrix elements are actually independent of the wave vector. For systems with complicated crystal structures, for which the Korringa-Kohn-Rostoker (KKR), Augmented-Plane Wave (APW) and Orthogonalized-Plane Wave (OPW) methods are difficult to apply, the present method leads to results with satisfactory accuracy and convergence.

'A civilizing mission'? Austrian medicine and the reform of medical structures in the Ottoman Empire, 1838-1850.

PubMed

Chahrour, Marcel

2007-12-01

During the 1840s, physicians from the Habsburg Empire played a decisive role in the reform of medical structures in the Ottoman Empire. This paper discusses different aspects of this scientific and cultural encounter. It emphasizes the importance of Austrian health care structures as a model for the work of these physicians in the Ottoman Empire and studies the role of the medical school ran by the Austrians as a means of representing, on the one hand, the reformatory efforts of the Ottoman Empire and, on the other hand, the motivations of the Habsburg monarchy for an involvement in Ottoman health care affairs, strongly bound up with its own quarantine politics towards the Ottoman Empire.

Methods for evaluating the predictive accuracy of structural dynamic models

NASA Technical Reports Server (NTRS)

Hasselman, T. K.; Chrostowski, Jon D.

1990-01-01

Uncertainty of frequency response using the fuzzy set method and on-orbit response prediction using laboratory test data to refine an analytical model are emphasized with respect to large space structures. Two aspects of the fuzzy set approach were investigated relative to its application to large structural dynamics problems: (1) minimizing the number of parameters involved in computing possible intervals; and (2) the treatment of extrema which may occur in the parameter space enclosed by all possible combinations of the important parameters of the model. Extensive printer graphics were added to the SSID code to help facilitate model verification, and an application of this code to the LaRC Ten Bay Truss is included in the appendix to illustrate this graphics capability.

Maturing Glycoproteomics Technologies Provide Unique Structural Insights into the N-glycoproteome and Its Regulation in Health and Disease*

PubMed Central

Packer, Nicolle H.; Schulz, Benjamin L.

2016-01-01

The glycoproteome remains severely understudied because of significant analytical challenges associated with glycoproteomics, the system-wide analysis of intact glycopeptides. This review introduces important structural aspects of protein N-glycosylation and summarizes the latest technological developments and applications in LC-MS/MS-based qualitative and quantitative N-glycoproteomics. These maturing technologies provide unique structural insights into the N-glycoproteome and its synthesis and regulation by complementing existing methods in glycoscience. Modern glycoproteomics is now sufficiently mature to initiate efforts to capture the molecular complexity displayed by the N-glycoproteome, opening exciting opportunities to increase our understanding of the functional roles of protein N-glycosylation in human health and disease. PMID:26929216

Mucin-Type O-Glycosylation in Invertebrates.

PubMed

Staudacher, Erika

2015-06-09

O-Glycosylation is one of the most important posttranslational modifications of proteins. It takes part in protein conformation, protein sorting, developmental processes and the modulation of enzymatic activities. In vertebrates, the basics of the biosynthetic pathway of O-glycans are already well understood. However, the regulation of the processes and the molecular aspects of defects, especially in correlation with cancer or developmental abnormalities, are still under investigation. The knowledge of the correlating invertebrate systems and evolutionary aspects of these highly conserved biosynthetic events may help improve the understanding of the regulatory factors of this pathway. Invertebrates display a broad spectrum of glycosylation varieties, providing an enormous potential for glycan modifications which may be used for the design of new pharmaceutically active substances. Here, overviews of the present knowledge of invertebrate mucin-type O-glycan structures and the currently identified enzymes responsible for the biosynthesis of these oligosaccharides are presented, and the few data dealing with functional aspects of O-glycans are summarised.

Ontology for customer centric digital services and analytics

NASA Astrophysics Data System (ADS)

Keat, Ng Wai; Shahrir, Mohammad Shazri

2017-11-01

In computer science research, ontologies are commonly utilised to create a unified abstract across many rich and different fields. In this paper, we apply the concept to the customer centric domain of digital services analytics and present an analytics solution ontology. The essence is based from traditional Entity Relationship Diagram (ERD), which then was abstracted out to cover wider areas on customer centric digital services. The ontology we developed covers both static aspects (customer identifiers) and dynamic aspects (customer's temporal interactions). The structure of the customer scape is modeled with classes that represent different types of customer touch points, ranging from digital and digital-stamps which represent physical analogies. The dynamic aspects of customer centric digital service are modeled with a set of classes, with the importance is represented in different associations involving establishment and termination of the target interaction. The realized ontology can be used in development of frameworks for customer centric applications, and for specification of common data format used by cooperating digital service applications.

Stress Prediction for Distributed Structural Health Monitoring Using Existing Measurements and Pattern Recognition.

PubMed

Lu, Wei; Teng, Jun; Zhou, Qiushi; Peng, Qiexin

2018-02-01

The stress in structural steel members is the most useful and directly measurable physical quantity to evaluate the structural safety in structural health monitoring, which is also an important index to evaluate the stress distribution and force condition of structures during structural construction and service phases. Thus, it is common to set stress as a measure in steel structural monitoring. Considering the economy and the importance of the structural members, there are only a limited number of sensors that can be placed, which means that it is impossible to obtain the stresses of all members directly using sensors. This study aims to develop a stress response prediction method for locations where there are insufficent sensors, using measurements from a limited number of sensors and pattern recognition. The detailed improved aspects are: (1) a distributed computing process is proposed, where the same pattern is recognized by several subsets of measurements; and (2) the pattern recognition using the subset of measurements is carried out by considering the optimal number of sensors and number of fusion patterns. The validity and feasibility of the proposed method are verified using two examples: the finite-element simulation of a single-layer shell-like steel structure, and the structural health monitoring of the space steel roof of Shenzhen Bay Stadium; for the latter, the anti-noise performance of this method is verified by the stress measurements from a real-world project.

Modeling the Car Crash Crisis Management System Using HiLA

NASA Astrophysics Data System (ADS)

Hölzl, Matthias; Knapp, Alexander; Zhang, Gefei

An aspect-oriented modeling approach to the Car Crash Crisis Management System (CCCMS) using the High-Level Aspect (HiLA) language is described. HiLA is a language for expressing aspects for UML static structures and UML state machines. In particular, HiLA supports both a static graph transformational and a dynamic approach of applying aspects. Furthermore, it facilitates methodologically turning use case descriptions into state machines: for each main success scenario, a base state machine is developed; all extensions to this main success scenario are covered by aspects. Overall, the static structure of the CCCMS is modeled in 43 classes, the main success scenarios in 13 base machines, the use case extensions in 47 static and 31 dynamic aspects, most of which are instantiations of simple aspect templates.

Patients' priorities in assessing organisational aspects of a general dental practice.

PubMed

Sonneveld, Rutger E; Brands, Wolter G; Bronkhorst, Ewald M; Welie, Jos V M; Truin, Gert-Jan

2013-02-01

To explore which organisational aspects are considered most important by patients when assessing a general dental practice, and which patients' characteristics influence their views on these aspects by a paper questionnaire. The questionnaire was handed out to a sample of 5,000 patients in the Netherlands. The response rate was 63%. Six organisational aspects out of a list of 41 aspects were valued as most important by at least 50%. In decreasing order of importance, these were: accessibility by telephone; continuing education for general dental practitioners; Dutch-speaking general dental practitioners; in-office waiting times; information about treatments offered; and waiting lists. For four out of these six aspects, respondents' age and education significantly influenced their preferences. Aspects concerning the infrastructure of a general dental practice were chosen more often than aspects such as working to professional standards, working according to protocols and guidelines, quality assessment and guaranteed treatment outcomes. The findings will enable organisations to increase the transparency of health-care delivery systems to focus on those organisational aspects of dental practices that patients themselves consider most important. These findings can also assist general dental practitioners in adapting their organisational services to the preferences of patients or specific patient groups. © 2013 FDI World Dental Federation.

Significant structural reinterpretation of the giant October Field, Gulf of Suez, Egypt using SCAT, isogon based sections and 3D seismic

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

Sercombe, W.J.; Smith, G.W.; Morse, J.D.

1996-01-01

The October field, a sub-salt giant in the extensional Gulf of Suez (Egypt) has been structurally reinterpreted for new reserve opportunities. Quantitative SCAT analyses of the wellbore dip data have been integrated with 3D seismic by using dip isogons to construct local structural sections. SCAT dip analysis was critical to the reinterpretation because SCAT revealed important structural information that previously was unresolvable using conventional tadpole plots. In gross aspect, the October Field is a homocline that trends NW-SE, dips to the NE, and is closed on the SW (updip) by the major Clysmic Normal Fault. SCAT accurately calculated the overallmore » trend of the field, but also identified important structural anomalies near the Clysmic fault and in the northwest and southeast plunge ends. In the northwest plunge end, SCAT has identified new, south dipping blocks that are transitional to the structurally-higher North October field. The southeast plunge end has been reinterpreted with correct azimuthal trends and new fault-block prospects. These new SCAT results have successfully improved the 3D seismic interpretation by providing a foundation of accurate in-situ structural control in an area of poor-to-fair seismic quality below the Miocene salt package.« less

Significant structural reinterpretation of the giant October Field, Gulf of Suez, Egypt using SCAT, isogon based sections and 3D seismic

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

Sercombe, W.J.; Smith, G.W.; Morse, J.D.

1996-12-31

The October field, a sub-salt giant in the extensional Gulf of Suez (Egypt) has been structurally reinterpreted for new reserve opportunities. Quantitative SCAT analyses of the wellbore dip data have been integrated with 3D seismic by using dip isogons to construct local structural sections. SCAT dip analysis was critical to the reinterpretation because SCAT revealed important structural information that previously was unresolvable using conventional tadpole plots. In gross aspect, the October Field is a homocline that trends NW-SE, dips to the NE, and is closed on the SW (updip) by the major Clysmic Normal Fault. SCAT accurately calculated the overallmore » trend of the field, but also identified important structural anomalies near the Clysmic fault and in the northwest and southeast plunge ends. In the northwest plunge end, SCAT has identified new, south dipping blocks that are transitional to the structurally-higher North October field. The southeast plunge end has been reinterpreted with correct azimuthal trends and new fault-block prospects. These new SCAT results have successfully improved the 3D seismic interpretation by providing a foundation of accurate in-situ structural control in an area of poor-to-fair seismic quality below the Miocene salt package.« less

Molecular aspects in clinical hemostasis research at Karolinska Institutet.

PubMed

Blombäck, Margareta

2010-05-21

The development of hemostasis research at Karolinska Institutet is described, focusing first on the initial findings of the fibrinogen structure and the hereditary bleeding disorders, hemophilia A and von Willebrand's disease. Basic research has focused on new biomarkers for cardiovascular/thromboembolic disorders, such as myocardial infarction and stroke, including preeclampsia and diabetes, with studies on the importance of decreased fibrinolysis in these disorders. Since long, the structure of the fibrin network has been evaluated, and recently the influence of aspirin and new thrombin and factor Xa inhibitors has been investigated. Research on the contact pathway of coagulation has also started at the Unit. 2010 Elsevier Inc. All rights reserved.

In utero mouse embryonic imaging with OCT for ophthalmologic research

NASA Astrophysics Data System (ADS)

Syed, Saba H.; Larina, Irina V.; Dickinson, Mary E.; Larin, Kirill V.

2011-03-01

Live imaging of an eye during embryonic development in mammalian model is important for understanding dynamic aspects of normal and abnormal eye morphogenesis. In this study, we used Swept Source Optical Coherence Tomography (SS-OCT) for live structural imaging of mouse embryonic eye through the uterine wall. The eye structure was reconstructed in mouse embryos at 13.5 to 17.5 days post coitus (dpc). Despite the limited imaging depth of OCT in turbid tissues, we were able to visualize the whole eye globe at these stages. These results suggest that live in utero OCT imaging is a useful tool to study embryonic eye development in the mouse model.

So you want to be a specialist registrar?--What to put in your CV.

PubMed

Ellis, P E; Ellis, S G S; O'Brien, K D; Joshi, R I

2002-02-09

Dentists applying to a specialist training programme often receive conflicting advice over what to put in their curriculum vitae (CV). We conducted a survey of the Training Programme Directors of the dental specialties to determine what aspects of CV content and presentation styles are considered important. This has allowed us to construct guidelines for what to put in a CV. Recently, structured application forms have become increasingly popular and may be a more objective way to carry out the shortlisting process. The guidelines presented could also be used as a framework for medical personnel departments if structured application forms eventually replace the CV.

A Converter from the Systems Biology Markup Language to the Synthetic Biology Open Language.

PubMed

Nguyen, Tramy; Roehner, Nicholas; Zundel, Zach; Myers, Chris J

2016-06-17

Standards are important to synthetic biology because they enable exchange and reproducibility of genetic designs. This paper describes a procedure for converting between two standards: the Systems Biology Markup Language (SBML) and the Synthetic Biology Open Language (SBOL). SBML is a standard for behavioral models of biological systems at the molecular level. SBOL describes structural and basic qualitative behavioral aspects of a biological design. Converting SBML to SBOL enables a consistent connection between behavioral and structural information for a biological design. The conversion process described in this paper leverages Systems Biology Ontology (SBO) annotations to enable inference of a designs qualitative function.

Neural Connectivity and Immunocytochemical Studies of Anatomical Sites Related to Nauseogenic and Emetic Reflexes

NASA Technical Reports Server (NTRS)

Fox, Robert A. (Principal Investigator)

1992-01-01

The studies conducted in this research project examined several aspects of neuroanatomical structures and neurochemical processes related to motion sickness in animal models. A principle objective of these studies was to investigate neurochemical changes in the central nervous system that are related to motion sickness with the objective of defining neural mechanisms important to this malady. For purposes of exposition, the studies and research finding have been classified into five categories. These are: immunoreactivity in the brainstem, vasopressin effects, lesion studies of area postrema, role of the vagus nerve, and central nervous system structure related to adaptation to microgravity.

Probing the structure of RecA-DNA filaments. Advantages of a fluorescent guanine analog.

PubMed

Singleton, Scott F; Roca, Alberto I; Lee, Andrew M; Xiao, Jie

2007-04-23

The RecA protein of Escherichia coli plays a crucial roles in DNA recombination and repair, as well as various aspects of bacterial pathogenicity. The formation of a RecA-ATP-ssDNA complex initiates all RecA activities and yet a complete structural and mechanistic description of this filament has remained elusive. An analysis of RecA-DNA interactions was performed using fluorescently labeled oligonucleotides. A direct comparison was made between fluorescein and several fluorescent nucleosides. The fluorescent guanine analog 6-methylisoxanthopterin (6MI) demonstrated significant advantages over the other fluorophores and represents an important new tool for characterizing RecA-DNA interactions.

Health Management Technology as a General Solution Framework

NASA Astrophysics Data System (ADS)

Nakajima, Hiroshi; Hasegawa, Yoshifumi; Tasaki, Hiroshi; Iwami, Taro; Tsuchiya, Naoki

Health maintenance and improvement of humans, artifacts, and nature are pressing requirements considering the problems human beings have faced. In this article, the health management technology is proposed by centering cause-effect structure. The important aspect of the technology is evolvement through human-machine collaboration in response to changes of target systems. One of the reasons why the cause-effect structure is centered in the technology is its feature of transparency to humans by instinct point of view. The notion has been spreaded over wide application areas such as quality control, energy management, and healthcare. Some experiments were conducted to prove effectiveness of the technology in the article.

Bioinformatics approaches for structural and functional analysis of proteins in secondary metabolism in Withania somnifera.

PubMed

Sanchita; Singh, Swati; Sharma, Ashok

2014-11-01

Withania somnifera (Ashwagandha) is an affluent storehouse of large number of pharmacologically active secondary metabolites known as withanolides. These secondary metabolites are produced by withanolide biosynthetic pathway. Very less information is available on structural and functional aspects of enzymes involved in withanolides biosynthetic pathways of Withiana somnifera. We therefore performed a bioinformatics analysis to look at functional and structural properties of these important enzymes. The pathway enzymes taken for this study were 3-Hydroxy-3-methylglutaryl coenzyme A reductase, 1-Deoxy-D-xylulose-5-phosphate synthase, 1-Deoxy-D-xylulose-5-phosphate reductase, farnesyl pyrophosphate synthase, squalene synthase, squalene epoxidase, and cycloartenol synthase. The prediction of secondary structure was performed for basic structural information. Three-dimensional structures for these enzymes were predicted. The physico-chemical properties such as pI, AI, GRAVY and instability index were also studied. The current information will provide a platform to know the structural attributes responsible for the function of these protein until experimental structures become available.

Additive-manufactured sandwich lattice structures: A numerical and experimental investigation

NASA Astrophysics Data System (ADS)

Fergani, Omar; Tronvoll, Sigmund; Brøtan, Vegard; Welo, Torgeir; Sørby, Knut

2017-10-01

The utilization of additive-manufactured lattice structures in engineered products is becoming more and more common as the competitiveness of AM as a production technology has increased during the past several years. Lattice structures may enable important weight reductions as well as open opportunities to build products with customized functional properties, thanks to the flexibility of AM for producing complex geometrical configurations. One of the most critical aspects related to taking AM into new application areas—such as safety critical products—is currently the limited understanding of the mechanical behavior of sandwich-based lattice structure mechanical under static and dynamic loading. In this study, we evaluate manufacturability of lattice structures and the impact of AM processing parameters on the structural behavior of this type of sandwich structures. For this purpose, we conducted static compression testing for a variety of geometry and manufacturing parameters. Further, the study discusses a numerical model capable of predicting the behavior of different lattice structure. A reasonably good correlation between the experimental and numerical results was observed.

Coastal habitats as surrogates for taxonomic, functional and trophic structures of benthic faunal communities.

PubMed

Törnroos, Anna; Nordström, Marie C; Bonsdorff, Erik

2013-01-01

Due to human impact, there is extensive degradation and loss of marine habitats, which calls for measures that incorporate taxonomic as well as functional and trophic aspects of biodiversity. Since such data is less easily quantifiable in nature, the use of habitats as surrogates or proxies for biodiversity is on the rise in marine conservation and management. However, there is a critical gap in knowledge of whether pre-defined habitat units adequately represent the functional and trophic structure of communities. We also lack comparisons of different measures of community structure in terms of both between- (β) and within-habitat (α) variability when accounting for species densities. Thus, we evaluated a priori defined coastal habitats as surrogates for traditional taxonomic, functional and trophic zoobenthic community structure. We focused on four habitats (bare sand, canopy-forming algae, seagrass above- and belowground), all easily delineated in nature and defined through classification systems. We analyzed uni- and multivariate data on species and trait diversity as well as stable isotope ratios of benthic macrofauna. A good fit between habitat types and taxonomic and functional structure was found, although habitats were more similar functionally. This was attributed to within-habitat heterogeneity so when habitat divisions matched the taxonomic structure, only bare sand was functionally distinct. The pre-defined habitats did not meet the variability of trophic structure, which also proved to differentiate on a smaller spatial scale. The quantification of trophic structure using species density only identified an epi- and an infaunal unit. To summarize the results we present a conceptual model illustrating the match between pre-defined habitat types and the taxonomic, functional and trophic community structure. Our results show the importance of including functional and trophic aspects more comprehensively in marine management and spatial planning.

Molecular dynamics simulations and structure-based network analysis reveal structural and functional aspects of G-protein coupled receptor dimer interactions.

PubMed

Baltoumas, Fotis A; Theodoropoulou, Margarita C; Hamodrakas, Stavros J

2016-06-01

A significant amount of experimental evidence suggests that G-protein coupled receptors (GPCRs) do not act exclusively as monomers but also form biologically relevant dimers and oligomers. However, the structural determinants, stoichiometry and functional importance of GPCR oligomerization remain topics of intense speculation. In this study we attempted to evaluate the nature and dynamics of GPCR oligomeric interactions. A representative set of GPCR homodimers were studied through Coarse-Grained Molecular Dynamics simulations, combined with interface analysis and concepts from network theory for the construction and analysis of dynamic structural networks. Our results highlight important structural determinants that seem to govern receptor dimer interactions. A conserved dynamic behavior was observed among different GPCRs, including receptors belonging in different GPCR classes. Specific GPCR regions were highlighted as the core of the interfaces. Finally, correlations of motion were observed between parts of the dimer interface and GPCR segments participating in ligand binding and receptor activation, suggesting the existence of mechanisms through which dimer formation may affect GPCR function. The results of this study can be used to drive experiments aimed at exploring GPCR oligomerization, as well as in the study of transmembrane protein-protein interactions in general.

Molecular dynamics simulations and structure-based network analysis reveal structural and functional aspects of G-protein coupled receptor dimer interactions

NASA Astrophysics Data System (ADS)

Baltoumas, Fotis A.; Theodoropoulou, Margarita C.; Hamodrakas, Stavros J.

2016-06-01

A significant amount of experimental evidence suggests that G-protein coupled receptors (GPCRs) do not act exclusively as monomers but also form biologically relevant dimers and oligomers. However, the structural determinants, stoichiometry and functional importance of GPCR oligomerization remain topics of intense speculation. In this study we attempted to evaluate the nature and dynamics of GPCR oligomeric interactions. A representative set of GPCR homodimers were studied through Coarse-Grained Molecular Dynamics simulations, combined with interface analysis and concepts from network theory for the construction and analysis of dynamic structural networks. Our results highlight important structural determinants that seem to govern receptor dimer interactions. A conserved dynamic behavior was observed among different GPCRs, including receptors belonging in different GPCR classes. Specific GPCR regions were highlighted as the core of the interfaces. Finally, correlations of motion were observed between parts of the dimer interface and GPCR segments participating in ligand binding and receptor activation, suggesting the existence of mechanisms through which dimer formation may affect GPCR function. The results of this study can be used to drive experiments aimed at exploring GPCR oligomerization, as well as in the study of transmembrane protein-protein interactions in general.

Full-scale monitoring of wind and suspension bridge response

NASA Astrophysics Data System (ADS)

Snæbjörnsson, J. T.; Jakobsen, J. B.; Cheynet, E.; Wang, J.

2017-12-01

Monitoring of real structures is important for many reasons. For structures susceptible to environmental actions, full-scale observations can provide valuable information about the environmental conditions at the site, as well as the characteristics of the excitation acting on the structure. The recorded data, if properly analyzed, can be used to validate and/or update experiments and models used in the design of new structures, such as the load description and modelling of the structural response. Various aspects of full-scale monitoring are discussed in the paper and the full-scale wind engineering laboratory at the Lysefjord suspension bridge introduced. The natural excitation of the bridge comes from wind and traffic. The surrounding terrain is complex and its effect on the wind flow can only be fully studied on site, in full-scale. The monitoring program and associated data analysis are described. These include various studies of the relevant turbulence characteristics, identification of dynamic properties and estimation of wind- and traffic-induced response parameters. The overall monitoring activity also included a novel application of the remote optical sensing in bridge engineering, which is found to have an important potential to complement traditional “single-point” wind observations by sonic anemometers.

Characterization of the Catalytic Structure of Plant Phytase, Protein Tyrosine Phosphatase-Like Phytase, and Histidine Acid Phytases and Their Biotechnological Applications

PubMed Central

Aires Almeida, Deborah; Aguiar, Raimundo Wagner de Souza; Viana, Kelvinson Fernandes; Barbosa, Luiz Carlos Bertucci; Cangussu, Edson Wagner da Silva; Brandi, Igor Viana; Portella, Augustus Caeser Franke; dos Santos, Gil Rodrigues; Sobrinho, Eliane Macedo; Lima, William James Nogueira

2018-01-01

Phytase plays a prominent role in monogastric animal nutrition due to its ability to improve phytic acid digestion in the gastrointestinal tract, releasing phosphorus and other micronutrients that are important for animal development. Moreover, phytase decreases the amounts of phytic acid and phosphate excreted in feces. Bioinformatics approaches can contribute to the understanding of the catalytic structure of phytase. Analysis of the catalytic structure can reveal enzymatic stability and the polarization and hydrophobicity of amino acids. One important aspect of this type of analysis is the estimation of the number of β-sheets and α-helices in the enzymatic structure. Fermentative processes or genetic engineering methods are employed for phytase production in transgenic plants or microorganisms. To this end, phytase genes are inserted in transgenic crops to improve the bioavailability of phosphorus. This promising technology aims to improve agricultural efficiency and productivity. Thus, the aim of this review is to present the characterization of the catalytic structure of plant and microbial phytases, phytase genes used in transgenic plants and microorganisms, and their biotechnological applications in animal nutrition, which do not impact negatively on environmental degradation. PMID:29713527

Characterization of the Catalytic Structure of Plant Phytase, Protein Tyrosine Phosphatase-Like Phytase, and Histidine Acid Phytases and Their Biotechnological Applications.

PubMed

Cangussu, Alex Sander Rodrigues; Aires Almeida, Deborah; Aguiar, Raimundo Wagner de Souza; Bordignon-Junior, Sidnei Emilio; Viana, Kelvinson Fernandes; Barbosa, Luiz Carlos Bertucci; Cangussu, Edson Wagner da Silva; Brandi, Igor Viana; Portella, Augustus Caeser Franke; Dos Santos, Gil Rodrigues; Sobrinho, Eliane Macedo; Lima, William James Nogueira

2018-01-01

Phytase plays a prominent role in monogastric animal nutrition due to its ability to improve phytic acid digestion in the gastrointestinal tract, releasing phosphorus and other micronutrients that are important for animal development. Moreover, phytase decreases the amounts of phytic acid and phosphate excreted in feces. Bioinformatics approaches can contribute to the understanding of the catalytic structure of phytase. Analysis of the catalytic structure can reveal enzymatic stability and the polarization and hydrophobicity of amino acids. One important aspect of this type of analysis is the estimation of the number of β -sheets and α -helices in the enzymatic structure. Fermentative processes or genetic engineering methods are employed for phytase production in transgenic plants or microorganisms. To this end, phytase genes are inserted in transgenic crops to improve the bioavailability of phosphorus. This promising technology aims to improve agricultural efficiency and productivity. Thus, the aim of this review is to present the characterization of the catalytic structure of plant and microbial phytases, phytase genes used in transgenic plants and microorganisms, and their biotechnological applications in animal nutrition, which do not impact negatively on environmental degradation.

Meanings and aspects of quality of life for cancer patients: a descriptive exploratory qualitative study.

PubMed

Bahrami, Masoud

2011-08-01

Given the importance of quality of life (QoL) for cancer patients, it is important to work out what this concept means not only for cancer patients, and for the nurses who care for them, but also the aspects of which it is composed. Therefore, an interpretive research study was conducted to explore in-depth meanings and aspects of QoL as expressed by cancer nurses. Participants were selected from different inpatient and outpatient oncology services and a palliative setting in Adelaide, South Australia. Results showed that many aspects contribute to an individual's QoL. These include the physical, the psychological, the spiritual, and both environmental and social interactions. More importantly, participants stated that spirituality is multifaceted and that there may be aspects in life that may be taken for granted. The meaning of patients' QoL was viewed by nurses as a patient's overall happiness and satisfaction. Also, nurses identified that providing choices to patients made an important contribution to a patient's QoL. Therefore, this exploration into the in-depth meanings and aspects of QoL for cancer patients from nurses' perspectives identified that, in addition to the aspects related to QoL that have been identified previously in the literature, aspects related to spirituality would need to be extensively covered, and providing choices to patients would be important in patients' QoL in an Australian setting.

Dynamic New World: Refining Our View of Protein Structure, Function and Evolution

PubMed Central

Mannige, Ranjan V.

2014-01-01

Proteins are crucial to the functioning of all lifeforms. Traditional understanding posits that a single protein occupies a single structure (“fold”), which performs a single function. This view is radically challenged with the recognition that high structural dynamism—the capacity to be extra “floppy”—is more prevalent in functional proteins than previously assumed. As reviewed here, this dynamic take on proteins affects our understanding of protein “structure”, function, and evolution, and even gives us a glimpse into protein origination. Specifically, this review will discuss historical developments concerning protein structure, and important new relationships between dynamism and aspects of protein sequence, structure, binding modes, binding promiscuity, evolvability, and origination. Along the way, suggestions will be provided for how key parts of textbook definitions—that so far have excluded membership to intrinsically disordered proteins (IDPs)—could be modified to accommodate our more dynamic understanding of proteins. PMID:28250374

Foreword to 'Multiscale structural biology: biophysical principles and mechanisms underlying the action of bio-nanomachines', a special issue in Honour of Fumio Arisaka's 70th birthday.

PubMed

Hall, Damien; Takagi, Junichi; Nakamura, Haruki

2018-04-01

This issue of Biophysical Reviews, titled 'Multiscale structural biology: biophysical principles and mechanisms underlying the action of bio-nanomachines', is a collection of articles dedicated in honour of Professor Fumio Arisaka's 70th birthday. Initially, working in the fields of haemocyanin and actin filament assembly, Fumio went on to publish important work on the elucidation of structural and functional aspects of T4 phage biology. As his career has transitioned levels of complexity from proteins (hemocyanin) to large protein complexes (actin) to even more massive bio-nanomachinery (phage), it is fitting that the subject of this special issue is similarly reflective of his multiscale approach to structural biology. This festschrift contains articles spanning biophysical structure and function from the bio-molecular through to the bio-nanomachine level.

Crystal structure of Streptococcus pneumoniae pneumolysin provides key insights into early steps of pore formation

PubMed Central

Lawrence, Sara L.; Feil, Susanne C.; Morton, Craig J.; Farrand, Allison J.; Mulhern, Terrence D.; Gorman, Michael A.; Wade, Kristin R.; Tweten, Rodney K.; Parker, Michael W.

2015-01-01

Pore-forming proteins are weapons often used by bacterial pathogens to breach the membrane barrier of target cells. Despite their critical role in infection important structural aspects of the mechanism of how these proteins assemble into pores remain unknown. Streptococcus pneumoniae is the world’s leading cause of pneumonia, meningitis, bacteremia and otitis media. Pneumolysin (PLY) is a major virulence factor of S. pneumoniae and a target for both small molecule drug development and vaccines. PLY is a member of the cholesterol-dependent cytolysins (CDCs), a family of pore-forming toxins that form gigantic pores in cell membranes. Here we present the structure of PLY determined by X-ray crystallography and, in solution, by small-angle X-ray scattering. The crystal structure reveals PLY assembles as a linear oligomer that provides key structural insights into the poorly understood early monomer-monomer interactions of CDCs at the membrane surface. PMID:26403197

Adoption of Smart Structures for Prevention of Health Hazards in Buildings

NASA Astrophysics Data System (ADS)

Oke, Ayodeji; Aigbavboa, Clinton; Ngema, Wiseman

2017-11-01

The importance of building quality to the health and well-being of occupants and surrounding neighbors cannot be overemphasized. Smart structures were construed to proffer solution to various issues of sustainable development including social factors that is concerned with health and safety of people. Based on existing literature materials on building quality, smart structures and general aspect of sustainable developments, this study examined the benefits of smart structures in the prevention of various health issues in infrastructural buildings, which has been a concern for stakeholders in the architecture, engineering and construction industry. The criterion for indoor environmental quality was adopted and various health and bodily issues related to building quality were explained. The adoption of smart structure concept will help to manage physical, chemical, biological and psychological factors of building with a view to enhancing better quality of life of occupants.

The mediating effect of social relationships on the association between socioeconomic status and subjective health - results from the Heinz Nixdorf Recall cohort study.

PubMed

Vonneilich, Nico; Jöckel, Karl-Heinz; Erbel, Raimund; Klein, Jens; Dragano, Nico; Siegrist, Johannes; von dem Knesebeck, Olaf

2012-04-17

Socioeconomic status (SES) is an important determinant of population health. Explanatory approaches on how SES determines health have so far included numerous factors, amongst them psychosocial factors such as social relationships. However, it is unclear whether social relationships can help explain socioeconomic differences in general subjective health. Do different aspects of social relationships contribute differently to the explanation? Based on a cohort study of middle and older aged residents (45 to 75 years) from the Ruhr Area in Germany our study tries to clarify the matter. For the analyses data from the population-based prospective Heinz Nixdorf Recall (HNR) Study is used. As indicators of SES education, equivalent household income and occupational status were employed. Social relations were assessed by including structural as well as functional aspects. Structural aspects were estimated by the Social Integration Index (SII) and functional aspects were measured by availability of emotional and instrumental support. Data on general subjective health status was available for both baseline examination (2000-2003) and a 5-year follow-up (2006-2008). The sample consists of 4,146 men and women. Four logistic regression models were calculated: in the first model we controlled for age and subjective health at baseline, while in models 2 and 3, either functional or structural aspects of social relationships were introduced separately. Model 4 then included all variables. As former studies indicated different health effects of SES and social relations in men and women, analyses were conducted with the overall sample as well as for each gender alone. Prospective associations of SES and subjective health were reduced after introducing social relationships into the regression models. Percentage reductions between 2% and 30% were observed in the overall sample when all aspects of social relations were included. The percentage reductions were strongest in the lowest SES group. Gender specific analyses revealed mediating effects of social relationships in women and men. The magnitude of mediating effects varied depending on the indicators of SES and social relations. Social relationships substantially contribute to the explanation of SES differences in subjective health. Interventions for improving social relations which especially focus on socially deprived groups are likely to help reducing socioeconomic disparities in health.

Probing Chemical Space with Alkaloid-Inspired Libraries

PubMed Central

McLeod, Michael C.; Singh, Gurpreet; Plampin, James N.; Rane, Digamber; Wang, Jenna L.; Day, Victor W.; Aubé, Jeffrey

2014-01-01

Screening of small molecule libraries is an important aspect of probe and drug discovery science. Numerous authors have suggested that bioactive natural products are attractive starting points for such libraries, due to their structural complexity and sp3-rich character. Here, we describe the construction of a screening library based on representative members of four families of biologically active alkaloids (Stemonaceae, the structurally related cyclindricine and lepadiformine families, lupin, and Amaryllidaceae). In each case, scaffolds were based on structures of the naturally occurring compounds or a close derivative. Scaffold preparation was pursued following the development of appropriate enabling chemical methods. Diversification provided 686 new compounds suitable for screening. The libraries thus prepared had structural characteristics, including sp3 content, comparable to a basis set of representative natural products and were highly rule-of-five compliant. PMID:24451589

[Motivation and self-directed learning among medical students].

PubMed

Fasce H, Eduardo; Ortega B, Javiera; Ibáñez G, Pilar; Márquez U, Carolina; Pérez V, Cristhian; Bustamante D, Carolina; Ortiz M, Liliana; Matus B, Olga; Bastías V, Nancy; Espinoza P, Camila

2016-05-01

Motivation is an essential aspect in the training process of medical students. The association that motivation can have with learning self-regulation is of utmost importance for the design of curriculum, teaching methods and evaluation. To describe the motivational aspects of self-directed learning among medical students from a traditional Chilean University. A qualitative, descriptive study based on grounded theory of Strauss and Corbin. Twenty 4th and 5th year medical students were selected using a maximum variation sampling technique. After obtaining an informed consent, semi-structured interviews and field notes were carried out. Data were analyzed to the level of open coding through Atlas-ti 7.5.2. From the student point of view, personal motivational aspects are linked to the search for information, constant updating, the perception of the physician-patient relationship and interest in subject matters. From the scope of teachers, a main issue is related to their ability to motivate students to develop independent study skills. Personal motivational aspects facilitate the development of independent study skills, specifically in the search of information. The role of teachers is crucial in promoting these skills and the perception of medical students from their learning process.

[Research Programs Conducted by the University of Virginia]. Part 1; Aquarius

NASA Technical Reports Server (NTRS)

Fuentes, Jose; Garstang, Michael; Macko, Stephen; Swap, Robert

2001-01-01

The hydrological cycle and the source of water vapor within the Amazon River Basin have important implications on questions of global thermal transport and regional ecological and socioeconomic sustainability. A three tiered approach taking advantage of satellite imagery, tipping buckets, and isotopic storm sampling at three basin sites was used to examine different aspects of regional meteoric water. By combining these techniques, it was possible to correlate observed storm structure with rain rates and intrastorm variations.

Development of Nano Plasmonic Structures for Multispectral IR Filters

DTIC Science & Technology

the polarization is parallel to the short ridge of the rectangle hole, it yields high optical transmission. The hole aspects are very important to the...Cross-shaped-hole arrays (CSHAs) are selected3 to diminish the polarization-dependent transmission differences of incident plane waves. The transmission...for the CSHA are set to 280nm and 50nm for period of 350nm, respectively; and the thicknesses of the metal films are set to 100nm. We varied the

Proteomic approaches in research of cyanobacterial photosynthesis.

PubMed

Battchikova, Natalia; Angeleri, Martina; Aro, Eva-Mari

2015-10-01

Oxygenic photosynthesis in cyanobacteria, algae, and plants is carried out by a fabulous pigment-protein machinery that is amazingly complicated in structure and function. Many different approaches have been undertaken to characterize the most important aspects of photosynthesis, and proteomics has become the essential component in this research. Here we describe various methods which have been used in proteomic research of cyanobacteria, and demonstrate how proteomics is implemented into on-going studies of photosynthesis in cyanobacterial cells.

Allocation, morphology, physiology, architecture: the multiple facets of plant above- and below-ground responses to resource stress.

PubMed

Freschet, Grégoire T; Violle, Cyrille; Bourget, Malo Y; Scherer-Lorenzen, Michael; Fort, Florian

2018-06-01

Plants respond to resource stress by changing multiple aspects of their biomass allocation, morphology, physiology and architecture. To date, we lack an integrated view of the relative importance of these plastic responses in alleviating resource stress and of the consistency/variability of these responses among species. We subjected nine species (legumes, forbs and graminoids) to nitrogen and/or light shortages and measured 11 above-ground and below-ground trait adjustments critical in the alleviation of these stresses (plus several underlying traits). Nine traits out of 11 showed adjustments that improved plants' potential capacity to acquire the limiting resource at a given time. Above ground, aspects of plasticity in allocation, morphology, physiology and architecture all appeared important in improving light capture, whereas below ground, plasticity in allocation and physiology were most critical to improving nitrogen acquisition. Six traits out of 11 showed substantial heterogeneity in species plasticity, with little structuration of these differences within trait covariation syndromes. Such comprehensive assessment of the complex nature of phenotypic responses of plants to multiple stress factors, and the comparison of plant responses across multiple species, makes a clear case for the high (but largely overlooked) diversity of potential plastic responses of plants, and for the need to explore the potential rules structuring them. © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

Measuring psychological flexibility in medical students and residents: a psychometric analysis

PubMed Central

Palladino, Christie L.; Ange, Brittany; Richardson, Deborah S.; Casillas, Rhonda; Decker, Matt; Gillies, Ralph A.; House, Amy; Rollock, Michael; Salazar, William H.; Waller, Jennifer L.; Zeidan, Ronnie; Stepleman, Lara

2013-01-01

Purpose Psychological flexibility involves mindful awareness of our thoughts and feelings without allowing them to prohibit acting consistently with our values and may have important implications for patient-centered clinical care. Although psychological flexibility appears quite relevant to the training and development of health care providers, prior research has not evaluated measures of psychological flexibility in medical learners. Therefore, we investigated the validity of our learners’ responses to three measures related to psychological flexibility. Methods Fourth-year medical students and residents (n=275) completed three measures of overlapping aspects of psychological flexibility: (1) Acceptance and Action Questionnaire-II (AAQ-II); (2) Cognitive Fusion Questionnaire (CFQ); and (3) Mindful Attention and Awareness Questionnaire (MAAS). We evaluated five aspects of construct validity: content, response process, internal structure, relationship with other variables, and consequences. Results We found good internal consistency for responses on the AAQ (α=0.93), MAAS (α=0.92), and CFQ (α=0.95). Factor analyses demonstrated a reasonable fit to previously published factor structures. As expected, scores on all three measures were moderately correlated with one another and with a measure of life satisfaction (p<0.01). Conclusion Our findings provide preliminary evidence supporting validity of the psychological flexibility construct in a medical education sample. As psychological flexibility is a central concept underlying self-awareness, this work may have important implications for clinical training and practice. PMID:23948496

Using Peer Feedback to Promote Reflection on Open-Ended Problems

NASA Astrophysics Data System (ADS)

Reinholz, Daniel L.; Dounas-Frazer, Dimitri R.

2016-09-01

This paper describes a new approach for learning from homework called Peer-Assisted Reflection (PAR). PAR involves students using peer feedback to improve their work on open-ended homework problems. Collaborating with peers and revising one's work based on the feedback of others are important aspects of doing and learning physics. While notable exceptions exist, homework and exams are generally individual activities that do not support collaboration and refinement, which misses important opportunities to use assessment for learning. In contrast, PAR provides students with a structure to iteratively engage with challenging, open-ended problems and solicit the input of their peers to improve their work.

Pointing control for LDR

NASA Technical Reports Server (NTRS)

Yam, Y.; Briggs, C.

1988-01-01

One important aspect of the LDR control problem is the possible excitations of structural modes due to random disturbances, mirror chopping, and slewing maneuvers. An analysis was performed to yield a first order estimate of the effects of such dynamic excitations. The analysis involved a study of slewing jitters, chopping jitters, disturbance responses, and pointing errors, making use of a simplified planar LDR model which describes the LDR dynamics on a plane perpendicular to the primary reflector. Briefly, the results indicate that the command slewing profile plays an important role in minimizing the resultant jitter, even to a level acceptable without any control action. An optimal profile should therefore be studied.

Relevance of rhodopsin studies for GPCR activation.

PubMed

Deupi, Xavier

2014-05-01

Rhodopsin, the dim-light photoreceptor present in the rod cells of the retina, is both a retinal-binding protein and a G protein-coupled receptor (GPCR). Due to this conjunction, it benefits from an arsenal of spectroscopy techniques that can be used for its characterization, while being a model system for the important family of Class A (also referred to as "rhodopsin-like") GPCRs. For instance, rhodopsin has been a crucial player in the field of GPCR structural biology. Until 2007, it was the only GPCR for which a high-resolution crystal structure was available, so all structure-activity analyses on GPCRs, from structure-based drug discovery to studies of structural changes upon activation, were based on rhodopsin. At present, about a third of currently available GPCR structures are still from rhodopsin. In this review, I show some examples of how these structures can still be used to gain insight into general aspects of GPCR activation. First, the analysis of the third intracellular loop in rhodopsin structures allows us to gain an understanding of the structural and dynamic properties of this region, which is absent (due to protein engineering or poor electron density) in most of the currently available GPCR structures. Second, a detailed analysis of the structure of the transmembrane domains in inactive, intermediate and active rhodopsin structures allows us to detect early conformational changes in the process of ligand-induced GPCR activation. Finally, the analysis of a conserved ligand-activated transmission switch in the transmembrane bundle of GPCRs in the context of the rhodopsin activation cycle, allows us to suggest that the structures of many of the currently available agonist-bound GPCRs may correspond to intermediate active states. While the focus in GPCR structural biology is inevitably moving away from rhodopsin, in other aspects rhodopsin is still at the forefront. For instance, the first studies of the structural basis of disease mutants in GPCRs, or the most detailed analysis of cellular GPCR signal transduction networks using a systems biology approach, have been carried out in rhodopsin. Finally, due again to its unique properties among GPCRs, rhodopsin will likely play an important role in the application of X-ray free electron laser crystallography to time-resolved structural biology in membrane proteins. Rhodopsin, thus, still remains relevant as a model system to study the molecular mechanisms of GPCR activation. This article is part of a Special Issue entitled: Retinal Proteins-You can teach an old dog new tricks. © 2013 Elsevier B.V. All rights reserved.

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

Structure and transport in organic semiconductor thin films

NASA Astrophysics Data System (ADS)

Vos, Sandra Elizabeth Fritz

Organic Semiconductors represent an exciting area of research due to their potential application in cheap and flexible electronics. In spite of the abundant interest in organic electronics the electronic transport mechanism remains poorly understood. Understanding the connection between molecular structure, crystal packing, intermolecular interactions and electronic delocalization is an important aspect of improving the transport properties of organics in thin film transistors (TFTs). In an organic thin film transistor, charge carrier transport is believed to occur within the first few monolayers of the organic material adjacent to the dielectric. It is therefore critical to understand the initial stages of film growth and molecular structure in these first few layers and relate this structure to electronic transport properties. The structure of organic films at the interface with an amorphous silicon dioxide ( a-SiO2) dielectric and how structure relates to transport in a TFT is the focus of this thesis. Pentacene films on a-SiO2 were extensively characterized with specular and in-plane X-ray diffraction, and CuKalpha1, and synchrotron radiation. The first layer of pentacene molecules adjacent to the a-SiO2 crystallized in a rectangular unit cell with the long axis of the molecules perpendicular to the substrate surface. Subsequent layers of pentacene crystallized in a slightly oblique in-plane unit cell that evolved as thickness was increased. The rectangular monolayer phase of pentacene did not persist when subsequent layers were deposited. Specular diffraction with Synchrotron radiation of a 160 A pentacene film (˜ 10 layers) revealed growth initiation of a bulk-like phase and persistence of the thin-film phase. Pentacene molecules were more tilted in the bulk-like phase and the in-plane unit cell was slightly more oblique. Pentacene grains began to grow randomly oriented with respect to the substrate surface (out-of-plane) in films near 650 A in thickness. The single crystal bulk phase of pentacene was observed from specular diffraction (CuKalpha1) of a 2.5 mum film. These results suggest that the thickness of pentacene films on a-SiO2 is an important aspect in the comparison of crystal structure and electronic transport.

A Delay Vector Variance based Marker for an Output-Only Assessment of Structural Changes in Tension Leg Platforms

NASA Astrophysics Data System (ADS)

Jaksic, V.; Wright, C.; Mandic, D. P.; Murphy, J.; Pakrashi, V.

2015-07-01

Although aspects of power generation of many offshore renewable devices are well understood, their dynamic responses under high wind and wave conditions are still to be investigated to a great detail. Output only statistical markers are important for these offshore devices, since access to the device is limited and information about the exposure conditions and the true behaviour of the devices are generally partial, limited, and vague or even absent. The markers can summarise and characterise the behaviour of these devices from their dynamic response available as time series data. The behaviour may be linear or nonlinear and consequently a marker that can track the changes in structural situations can be quite important. These markers can then be helpful in assessing the current condition of the structure and can indicate possible intervention, monitoring or assessment. This paper considers a Delay Vector Variance based marker for changes in a tension leg platform tested in an ocean wave basin for structural changes brought about by single column dampers. The approach is based on dynamic outputs of the device alone and is based on the estimation of the nonlinearity of the output signal. The advantages of the selected marker and its response with changing structural properties are discussed. The marker is observed to be important for monitoring the as- deployed structural condition and is sensitive to changes in such conditions. Influence of exposure conditions of wave loading is also discussed in this study based only on experimental data.

Optimal Control Allocation with Load Sensor Feedback for Active Load Suppression, Experiment Development

NASA Technical Reports Server (NTRS)

Miller, Christopher J.; Goodrick, Dan

2017-01-01

The problem of control command and maneuver induced structural loads is an important aspect of any control system design. The aircraft structure and the control architecture must be designed to achieve desired piloted control responses while limiting the imparted structural loads. The classical approach is to utilize high structural margins, restrict control surface commands to a limited set of analyzed combinations, and train pilots to follow procedural maneuvering limitations. With recent advances in structural sensing and the continued desire to improve safety and vehicle fuel efficiency, it is both possible and desirable to develop control architectures that enable lighter vehicle weights while maintaining and improving protection against structural damage. An optimal control technique has been explored and shown to achieve desirable vehicle control performance while limiting sensed structural loads. The subject of this paper is the design of the optimal control architecture, and provides the reader with some techniques for tailoring the architecture, along with detailed simulation results.

Structural kinematics based damage zone prediction in gradient structures using vibration database

NASA Astrophysics Data System (ADS)

Talha, Mohammad; Ashokkumar, Chimpalthradi R.

2014-05-01

To explore the applications of functionally graded materials (FGMs) in dynamic structures, structural kinematics based health monitoring technique becomes an important problem. Depending upon the displacements in three dimensions, the health of the material to withstand dynamic loads is inferred in this paper, which is based on the net compressive and tensile displacements that each structural degree of freedom takes. These net displacements at each finite element node predicts damage zones of the FGM where the material is likely to fail due to a vibration response which is categorized according to loading condition. The damage zone prediction of a dynamically active FGMs plate have been accomplished using Reddy's higher-order theory. The constituent material properties are assumed to vary in the thickness direction according to the power-law behavior. The proposed C0 finite element model (FEM) is applied to get net tensile and compressive displacement distributions across the structures. A plate made of Aluminum/Ziconia is considered to illustrate the concept of structural kinematics-based health monitoring aspects of FGMs.

Nanodosimetric track structure in homogeneous extended beams.

PubMed

Conte, V; Moro, D; Colautti, P; Grosswendt, B

2015-09-01

Physical aspects of particle track structure are important in determining the induction of clustered damage in relevant subcellular structures like the DNA and higher-order genomic structures. The direct measurement of track-structure properties of ionising radiation is feasible today by counting the number of ionisations produced inside a small gas volume. In particular, the so-called track-nanodosimeter, installed at the TANDEM-ALPI accelerator complex of LNL, measures ionisation cluster-size distributions in a simulated subcellular structure of dimensions 20 nm, corresponding approximately to the diameter of the chromatin fibre. The target volume is irradiated by pencil beams of primary particles passing at specified impact parameter. To directly relate these measured track-structure data to radiobiological measurements performed in broad homogeneous particle beams, these data can be integrated over the impact parameter. This procedure was successfully applied to 240 MeV carbon ions and compared with Monte Carlo simulations for extended fields. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Friction Stir Welding

NASA Technical Reports Server (NTRS)

Nunes, Arthur C., Jr.

2008-01-01

Friction stir welding (FSW) is a solid state welding process invented in 1991 at The Welding Institute in the United Kingdom. A weld is made in the FSW process by translating a rotating pin along a weld seam so as to stir the sides of the seam together. FSW avoids deleterious effects inherent in melting and promises to be an important welding process for any industries where welds of optimal quality are demanded. This article provides an introduction to the FSW process. The chief concern is the physical effect of the tool on the weld metal: how weld seam bonding takes place, what kind of weld structure is generated, potential problems, possible defects for example, and implications for process parameters and tool design. Weld properties are determined by structure, and the structure of friction stir welds is determined by the weld metal flow field in the vicinity of the weld tool. Metal flow in the vicinity of the weld tool is explained through a simple kinematic flow model that decomposes the flow field into three basic component flows: a uniform translation, a rotating solid cylinder, and a ring vortex encircling the tool. The flow components, superposed to construct the flow model, can be related to particular aspects of weld process parameters and tool design; they provide a bridge to an understanding of a complex-at-first-glance weld structure. Torques and forces are also discussed. Some simple mathematical models of structural aspects, torques, and forces are included.

Elements of an algorithm for optimizing a parameter-structural neural network

NASA Astrophysics Data System (ADS)

Mrówczyńska, Maria

2016-06-01

The field of processing information provided by measurement results is one of the most important components of geodetic technologies. The dynamic development of this field improves classic algorithms for numerical calculations in the aspect of analytical solutions that are difficult to achieve. Algorithms based on artificial intelligence in the form of artificial neural networks, including the topology of connections between neurons have become an important instrument connected to the problem of processing and modelling processes. This concept results from the integration of neural networks and parameter optimization methods and makes it possible to avoid the necessity to arbitrarily define the structure of a network. This kind of extension of the training process is exemplified by the algorithm called the Group Method of Data Handling (GMDH), which belongs to the class of evolutionary algorithms. The article presents a GMDH type network, used for modelling deformations of the geometrical axis of a steel chimney during its operation.

Frizzled 7 and PIP2 binding by syntenin PDZ2 domain supports Frizzled 7 trafficking and signalling

NASA Astrophysics Data System (ADS)

Egea-Jimenez, Antonio Luis; Gallardo, Rodrigo; Garcia-Pino, Abel; Ivarsson, Ylva; Wawrzyniak, Anna Maria; Kashyap, Rudra; Loris, Remy; Schymkowitz, Joost; Rousseau, Frederic; Zimmermann, Pascale

2016-07-01

PDZ domain-containing proteins work as intracellular scaffolds to control spatio-temporal aspects of cell signalling. This function is supported by the ability of their PDZ domains to bind other proteins such as receptors, but also phosphoinositide lipids important for membrane trafficking. Here we report a crystal structure of the syntenin PDZ tandem in complex with the carboxy-terminal fragment of Frizzled 7 and phosphatidylinositol 4,5-bisphosphate (PIP2). The crystal structure reveals a tripartite interaction formed via the second PDZ domain of syntenin. Biophysical and biochemical experiments establish co-operative binding of the tripartite complex and identify residues crucial for membrane PIP2-specific recognition. Experiments with cells support the importance of the syntenin-PIP2 interaction for plasma membrane targeting of Frizzled 7 and c-jun phosphorylation. This study contributes to our understanding of the biology of PDZ proteins as key players in membrane compartmentalization and dynamics.

Upper Face: Clinical Anatomy and Regional Approaches with Injectable Fillers.

PubMed

Sykes, Jonathan M; Cotofana, Sebastian; Trevidic, Patrick; Solish, Nowell; Carruthers, Jean; Carruthers, Alastair; Moradi, Amir; Swift, Arthur; Massry, Guy G; Lambros, Val; Remington, B Kent

2015-11-01

The use of facial fillers has been rapidly increased as the range of injectable products and indications continues to expand. Complications may arise from improper placement or technique. This article highlights the importance of anatomic knowledge when using injectable fillers in the face. A detailed review of the clinical anatomy of the upper face is performed. Regional approaches are described using the applied anatomy to efficiently and safely augment the different subunits of the upper face. Key aspects of safe and successful injection of fillers in the upper face include a thorough knowledge of the location of fat compartments and neurovascular structures. Awareness of these structures enables the practitioner to maximize injections, while avoiding damage to important nerves and vessels. A detailed knowledge of the anatomy and properties of the product is paramount to maximize the efficacy while minimizing the risk of complications.

Analysis of cracked RC beams under vibration

NASA Astrophysics Data System (ADS)

Capozucca, R.; Magagnini, E.

2017-05-01

Among the methods of monitoring of integrity, vibration analysis is more convenient as non-destructive testing (NDT) method. Many aspects regarding the vibration monitoring of the structural integrity of damaged RC elements have not been completely analysed in literature. The correlation between the development of the crack pattern on concrete surface under bending loadings, as well as the width and depth of cracks, and the variation of dynamic parameters on a structural element is an important aspects that has to be more investigated. This paper deals with cracked RC beams controlled by NDT based on natural vibration, which may be correlated to damage degree due to cracking of concrete under severe state of loading. An experimental investigation on the assessment of RC beams in different scale under loading has been done through dynamic tests in different constraint conditions of edges measuring frequency values and frequency variation. Envelope of Frequency Response Functions (FRFs) are shown and the changes of natural frequency values are related to the damage degree of RC beams subjected to static tests. Finally, a comparison between data obtained by finite element analysis and experimental results is shown.

THE TRANSMISSION AND PERSISTENCE OF ‘URBAN LEGENDS’: SOCIOLOGICAL APPLICATION OF AGE-STRUCTURED EPIDEMIC MODELS

PubMed Central

NOYMER, ANDREW

2009-01-01

This paper describes two related epidemic models of rumor transmission in an age-structured population. Rumors share with communicable disease certain basic aspects, which means that formal models of epidemics may be applied to the transmission of rumors. The results show that rumors may become entrenched very quickly and persist for a long time, even when skeptics are modeled to take an active role in trying to convince others that the rumor is false. This is a macrophenomeon, because individuals eventually cease to believe the rumor, but are replaced by new recruits. This replacement of former believers by new ones is an aspect of all the models, but the approach to stability is quicker, and involves smaller chance of extinction, in the model where skeptics actively try to counter the rumor, as opposed to the model where interest is naturally lost by believers. Skeptics hurt their own cause. The result shows that including age, or a variable for which age is a proxy (e.g., experience), can improve model fidelity and yield important insights. PMID:20351799

Poorly Understood Aspects of Striated Muscle Contraction

PubMed Central

Månsson, Alf

2015-01-01

Muscle contraction results from cyclic interactions between the contractile proteins myosin and actin, driven by the turnover of adenosine triphosphate (ATP). Despite intense studies, several molecular events in the contraction process are poorly understood, including the relationship between force-generation and phosphate-release in the ATP-turnover. Different aspects of the force-generating transition are reflected in the changes in tension development by muscle cells, myofibrils and single molecules upon changes in temperature, altered phosphate concentration, or length perturbations. It has been notoriously difficult to explain all these events within a given theoretical framework and to unequivocally correlate observed events with the atomic structures of the myosin motor. Other incompletely understood issues include the role of the two heads of myosin II and structural changes in the actin filaments as well as the importance of the three-dimensional order. We here review these issues in relation to controversies regarding basic physiological properties of striated muscle. We also briefly consider actomyosin mutation effects in cardiac and skeletal muscle function and the possibility to treat these defects by drugs. PMID:25961006

Poorly understood aspects of striated muscle contraction.

PubMed

Månsson, Alf; Rassier, Dilson; Tsiavaliaris, Georgios

2015-01-01

Muscle contraction results from cyclic interactions between the contractile proteins myosin and actin, driven by the turnover of adenosine triphosphate (ATP). Despite intense studies, several molecular events in the contraction process are poorly understood, including the relationship between force-generation and phosphate-release in the ATP-turnover. Different aspects of the force-generating transition are reflected in the changes in tension development by muscle cells, myofibrils and single molecules upon changes in temperature, altered phosphate concentration, or length perturbations. It has been notoriously difficult to explain all these events within a given theoretical framework and to unequivocally correlate observed events with the atomic structures of the myosin motor. Other incompletely understood issues include the role of the two heads of myosin II and structural changes in the actin filaments as well as the importance of the three-dimensional order. We here review these issues in relation to controversies regarding basic physiological properties of striated muscle. We also briefly consider actomyosin mutation effects in cardiac and skeletal muscle function and the possibility to treat these defects by drugs.

3D Study of the Morphology and Dynamics of Zeolite Nucleation.

PubMed

Melinte, Georgian; Georgieva, Veselina; Springuel-Huet, Marie-Anne; Nossov, Andreï; Ersen, Ovidiu; Guenneau, Flavien; Gedeon, Antoine; Palčić, Ana; Bozhilov, Krassimir N; Pham-Huu, Cuong; Qiu, Shilun; Mintova, Svetlana; Valtchev, Valentin

2015-12-07

The principle aspects and constraints of the dynamics and kinetics of zeolite nucleation in hydrogel systems are analyzed on the basis of a model Na-rich aluminosilicate system. A detailed time-series EMT-type zeolite crystallization study in the model hydrogel system was performed to elucidate the topological and temporal aspects of zeolite nucleation. A comprehensive set of analytical tools and methods was employed to analyze the gel evolution and complement the primary methods of transmission electron microscopy (TEM) and nuclear magnetic resonance (NMR) spectroscopy. TEM tomography reveals that the initial gel particles exhibit a core-shell structure. Zeolite nucleation is topologically limited to this shell structure and the kinetics of nucleation is controlled by the shell integrity. The induction period extends to the moment when the shell is consumed and the bulk solution can react with the core of the gel particles. These new findings, in particular the importance of the gel particle shell in zeolite nucleation, can be used to control the growth process and properties of zeolites formed in hydrogels. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Moored offshore structures - evaluation of forces in elastic mooring lines

NASA Astrophysics Data System (ADS)

Crudu, L.; Obreja, D. C.; Marcu, O.

2016-08-01

In most situations, the high frequency motions of the floating structure induce important effects in the mooring lines which affect also the motions of the structure. The experience accumulated during systematic experimental tests and calculations, carried out for different moored floating structures, showed a complex influence of various parameters on the dynamic effects. Therefore, it was considered that a systematic investigation is necessary. Due to the complexity of hydrodynamics aspects of offshore structures behaviour, experimental tests are practically compulsory in order to be able to properly evaluate and then to validate their behaviour in real sea. Moreover the necessity to carry out hydrodynamic tests is often required by customers, classification societies and other regulatory bodies. Consequently, the correct simulation of physical properties of the complex scaled models becomes a very important issue. The paper is investigating such kind of problems identifying the possible simplification, generating different approaches. One of the bases of the evaluation has been found consideringtheresults of systematic experimental tests on the dynamic behaviour of a mooring chain reproduced at five different scales. Dynamic effects as well as the influences of the elasticity simulation for 5 different scales are evaluated together. The paper presents systematic diagrams and practical results for a typical moored floating structure operating as pipe layer based on motion evaluations and accelerations in waves.

Human Milk Oligosaccharides (HMOS): Structure, Function, and Enzyme-Catalyzed Synthesis.

PubMed

Chen, Xi

2015-01-01

The important roles played by human milk oligosaccharides (HMOS), the third major component of human milk, in the health of breast-fed infants have been increasingly recognized, as the structures of more than 100 different HMOS have now been elucidated. Despite the recognition of the various functions of HMOS as prebiotics, antiadhesive antimicrobials, and immunomodulators, the roles and the applications of individual HMOS species are less clear. This is mainly due to the limited accessibility to large amounts of individual HMOS in their pure forms. Current advances in the development of enzymatic, chemoenzymatic, whole-cell, and living-cell systems allow for the production of a growing number of HMOS in increasing amounts. This effort will greatly facilitate the elucidation of the important roles of HMOS and allow exploration into the applications of HMOS both as individual compounds and as mixtures of defined structures with desired functions. The structures, functions, and enzyme-catalyzed synthesis of HMOS are briefly surveyed to provide a general picture about the current progress on these aspects. Future efforts should be devoted to elucidating the structures of more complex HMOS, synthesizing more complex HMOS including those with branched structures, and developing HMOS-based or HMOS-inspired prebiotics, additives, and therapeutics. © 2015 Elsevier Inc. All rights reserved.

Course 12: Proteins: Structural, Thermodynamic and Kinetic Aspects

NASA Astrophysics Data System (ADS)

Finkelstein, A. V.

1 Introduction 2 Overview of protein architectures and discussion of physical background of their natural selection 2.1 Protein structures 2.2 Physical selection of protein structures 3 Thermodynamic aspects of protein folding 3.1 Reversible denaturation of protein structures 3.2 What do denatured proteins look like? 3.3 Why denaturation of a globular protein is the first-order phase transition 3.4 "Gap" in energy spectrum: The main characteristic that distinguishes protein chains from random polymers 4 Kinetic aspects of protein folding 4.1 Protein folding in vivo 4.2 Protein folding in vitro (in the test-tube) 4.3 Theory of protein folding rates and solution of the Levinthal paradox

A novel fabrication method for suspended high-aspect-ratio microstructures

NASA Astrophysics Data System (ADS)

Yang, Yao-Joe; Kuo, Wen-Cheng

2005-11-01

Suspended high-aspect-ratio structures (suspended HARS) are widely used for MEMS devices such as micro-gyroscopes, micro-accelerometers, optical switches and so on. Various fabrication methods, such as SOI, SCREAM, AIM, SBM and BELST processes, were proposed to fabricate HARS. However, these methods focus on the fabrication of suspended microstructures with relatively small widths of trench opening (e.g. less than 10 µm). In this paper, we propose a novel process for fabricating very high-aspect-ratio suspended structures with large widths of trench opening using photoresist as an etching mask. By enhancing the microtrenching effect, we can easily release the suspended structure without thoroughly removing the floor polymer inside the trenches for the cases with a relatively small trench aspect ratio. All the process steps can be integrated into a single-run single-mask ICP-RIE process, which effectively reduces the process complexity and fabrication cost. We also discuss the phenomenon of corner erosion, which results in the undesired etching of silicon structures during the structure-releasing step. By using the proposed process, 100 µm thick suspended structures with the trench aspect ratio of about 20 are demonstrated. Also, the proposed process can be used to fabricate devices for applications which require large in-plane displacement. This paper was orally presented in the Transducers'05, Seoul, Korea (paper ID: 3B1.3).

Realization of high quality production schedules: Structuring quality factors via iteration of user specification processes

NASA Technical Reports Server (NTRS)

Hamazaki, Takashi

1992-01-01

This paper describes an architecture for realizing high quality production schedules. Although quality is one of the most important aspects of production scheduling, it is difficult, even for a user, to specify precisely. However, it is also true that the decision as to whether a scheduler is good or bad can only be made by the user. This paper proposes the following: (1) the quality of a schedule can be represented in the form of quality factors, i.e. constraints and objectives of the domain, and their structure; (2) quality factors and their structure can be used for decision making at local decision points during the scheduling process; and (3) that they can be defined via iteration of user specification processes.

Development of methodologies for the estimation of thermal properties associated with aerospace vehicles

NASA Technical Reports Server (NTRS)

Scott, Elaine P.

1993-01-01

Thermal stress analyses are an important aspect in the development of aerospace vehicles such as the National Aero-Space Plane (NASP) and the High-Speed Civil Transport (HSCT) at NASA-LaRC. These analyses require knowledge of the temperature within the structures which consequently necessitates the need for thermal property data. The initial goal of this research effort was to develop a methodology for the estimation of thermal properties of aerospace structural materials at room temperature and to develop a procedure to optimize the estimation process. The estimation procedure was implemented utilizing a general purpose finite element code. In addition, an optimization procedure was developed and implemented to determine critical experimental parameters to optimize the estimation procedure. Finally, preliminary experiments were conducted at the Aircraft Structures Branch (ASB) laboratory.

Development of methodologies for the estimation of thermal properties associated with aerospace vehicles

NASA Astrophysics Data System (ADS)

Scott, Elaine P.

1993-12-01

Thermal stress analyses are an important aspect in the development of aerospace vehicles such as the National Aero-Space Plane (NASP) and the High-Speed Civil Transport (HSCT) at NASA-LaRC. These analyses require knowledge of the temperature within the structures which consequently necessitates the need for thermal property data. The initial goal of this research effort was to develop a methodology for the estimation of thermal properties of aerospace structural materials at room temperature and to develop a procedure to optimize the estimation process. The estimation procedure was implemented utilizing a general purpose finite element code. In addition, an optimization procedure was developed and implemented to determine critical experimental parameters to optimize the estimation procedure. Finally, preliminary experiments were conducted at the Aircraft Structures Branch (ASB) laboratory.

Ion-Neutral Coupling in Solar Prominence

NASA Technical Reports Server (NTRS)

Gilbert, H.; DeVore, C. R.; Karpen, J.; Kucera, T.; Antiochos, S.; Kawashima, R.

2011-01-01

Coupling between ions and neutrals in magnetized plasmas is fundamentally important to many aspects of heliophysics, including our ionosphere, the solar chromosphere, the solar wind interaction with planetary atmospheres, and the interface between the heliosphere and the interstellar medium. Ion-neutral coupling also plays a major role in the physics of solar prominences. By combining theory, modeling, and observations we are working toward a better understanding of the structure and dynamics of partially ionized prominence plasma. Two key questions are addressed in the present work: 1) what physical mechanism(s) sets the cross-field scale of prominence threads? 2) Are ion-neutral interactions responsible for the vertical flows and structure in prominences? We present initial results from a study investigating what role ion-neutral interactions play in prominence dynamics and structure. This research was supported by NASA.

High-Aspect-Ratio Ridge Structures Induced by Plastic Deformation as a Novel Microfabrication Technique.

PubMed

Takei, Atsushi; Jin, Lihua; Fujita, Hiroyuki; Takei, A; Fujita, H; Jin, Lihua

2016-09-14

Wrinkles on thin film/elastomer bilayer systems provide functional surfaces. The aspect ratio of these wrinkles is critical to their functionality. Much effort has been dedicated to creating high-aspect-ratio structures on the surface of bilayer systems. A highly prestretched elastomer attached to a thin film has recently been shown to form a high-aspect-ratio structure, called a ridge structure, due to a large strain induced in the elastomer. However, the prestretch requirements of the elastomer during thin film attachment are not compatible with conventional thin film deposition methods, such as spin coating, dip coating, and chemical vapor deposition (CVD). Thus, the fabrication method is complex, and ridge structure formation is limited to planar surfaces. This paper presents a new and simple method for constructing ridge structures on a nonplanar surface using a plastic thin film/elastomer bilayer system. A plastic thin film is attached to a stress-free elastomer, and the resulting bilayer system is highly stretched one- or two-dimensionally. Upon the release of the stretch load, the deformation of the elastomer is reversible, while the plastically deformed thin film stays elongated. The combination of the length mismatch and the large strain induced in the elastomer generates ridge structures. The morphology of the plastic thin film/elastomer bilayer system is experimentally studied by varying the physical parameters, and the functionality and the applicability to a nonplanar surface are demonstrated. Finally, we simulate the effect of plasticity on morphology. This study presents a new technique for generating microscale high-aspect-ratio structures and its potential for functional surfaces.

Effect of Er3+ doping on structural, morphological and photocatalytical properties of ZnO thin films

NASA Astrophysics Data System (ADS)

Bouhouche, S.; Bensouici, F.; Toubane, M.; Azizi, A.; Otmani, A.; Chebout, K.; Kezzoula, F.; Tala-Ighil, R.; Bououdina, M.

2018-05-01

In this research work, structure, microstructure, optical and photocatalytic properties of undoped and Erbium doped nanostructured ZnO thin films prepared by sol-gel dip-coating are investigated. X-ray diffraction (XRD) analysis indicates that the deposited films crystallize within the hexagonal wurtzite-type structure with a preferential growth orientation along (002) plane. Morphological observations using scanning electron microscopy (SEM) reveal important influence of Er concentration; displaying homogeneous and dense aspect for undoped to 0.3% then grid-like morphology for 0.4 and 0.5%. UV/vis/NIR transmittance spectroscopy spectra display a transmittance over 70%, and small variation in the energy gap energy 3.263–3.278 eV. Wettability test of ZnO thin films surface ranges from hydrophilic aspect for pure ZnO to hydrophobic one for Er doped ZnO, and the contact angle is found to increase from 58.7° for pure ZnO up to 98.4° for 0.4% Er doped ZnO. The photocatalytic activity measurements evaluated using the degradation of methylene blue (MB) under UV light irradiation demonstrate that undoped ZnO film shows higher photocatalytic activity compared to Er doped ZnO films, which may be attributed to the deterioration of films’crystallinity resulting in lower transmittance.

Biological and Chemical Aspects of Natural Biflavonoids from Plants: A Brief Review.

PubMed

Gontijo, Vanessa Silva; Dos Santos, Marcelo Henrique; Viegas, Claudio

2017-01-01

Biflavonoids belong to a subclass of the plant flavonoids family and are limited to several species in the plant kingdom. In the literature, biflavonoids are extensively reported for their pharmacological properties including anti-inflammatory, antioxidant, inhibitory activity against phospholipase A2 (PLA2) and antiprotozoal activity. These activities have been discovered from the small number of biflavonoid structures that have been investigated, although the natural biflavonoids library is likely to be large. In addition, many medicinal properties and traditional use of plants are attributed to the presence of bioflavonoids among their secondary metabolites. Structurally, biflavonoids are polyphenol compounds comprising of two identical or non-identical flavonflavonoid units joined in a symmetrical or unsymmetrical manner through an alkyl or an alkoxy-based linker of varying length. Due to their chemical and biological importance, several bioprospective phytochemical studies and chemical approaches using coupling and molecular rearrangement strategies have been developed to identify and synthesize new bioactive biflavonoids. In this brief review, we present some basic structural aspects for classification and nomenclature of bioflavonoids and a compilation of the literature data published in the last 7 years, concerning the discovery of new natural biflavonoids of plant origin and their pharmacological and biological properties. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Food texture analysis in the 21st century

USDA-ARS?s Scientific Manuscript database

The study of food texture encompasses sensory, physiological, and structural aspects. Research in this area must be multidisciplinary in nature, accounting for consumer perception and acceptability, rheology, and structural aspects. This brief review of the field covers sensory panels, instrumenta...

Parametric study of guided waves dispersion curves for composite plates

NASA Astrophysics Data System (ADS)

Predoi, Mihai Valentin; Petre, Cristian Cǎtǎlin; Kettani, Mounsif Ech Cherif El; Leduc, Damien

2018-02-01

Nondestructive testing of composite panels benefit from the relatively long range propagation of guided waves in sandwich structures. The guided waves are sensitive to delamination, air bubbles inclusions and cracks and can thus bring information about hidden defects in the composite panel. The preliminary data in all such inspections is represented by the dispersion curves, representing the dependency of the phase/group velocity on the frequency for the propagating modes. In fact, all modes are more or less attenuated, so it is even more important to compute the dispersion curves, which provide also the modal attenuation as function of frequency. Another important aspect is the sensitivity of the dispersion curves on each of the elastic constant of the composite, which are orthotropic in most cases. All these aspects are investigated in the present work, based on our specially developed finite element numerical model implemented in Comsol, which has several advantages over existing methods. The dispersion curves and modal displacements are computed for an example of composite plate. Comparison with literature data validates the accuracy of our results.

What do medical residents learn on a rural Japanese island?

PubMed Central

Ohta, Ryuichi; Son, Daisuke

2018-01-01

Objective: Community-based medical education (CBME) serves as a complement to university medical education, and it is practiced in several urban undergraduate and postgraduate curriculums. However, there are few reports on CBME learning content in rural Japanese settings. Materials and Methods: This research aimed to clarify learning content through semi-structured interviews and qualitative analysis of second-year residents who studied on a remote, rural island located 400 km from the mainland of Okinawa, Japan. Analysis was based on Steps for Coding and Theorization (SCAT). Results: Fifteen concepts were extracted, and four categories were generated: a strong connection among the islanders, the necessary abilities for rural physicians, islander-centered care, and the differences between rural and hospital medicine. In contrast to hospital medicine, various kinds of learning occurred in deep relationships with the islanders. Conclusion: Through CBME on a remote island, the residents learned not only about medical aspects, but also the importance of community health through the social and cultural aspects, whole-person medical care in a remote location, and the importance of reflection in their self-directed learning. PMID:29875892

Chemical Ecology of Stingless Bees.

PubMed

Leonhardt, Sara Diana

2017-04-01

Stingless bees (Hymenoptera, Apidae: Meliponini) represent a highly diverse group of social bees confined to the world's tropics and subtropics. They show a striking diversity of structural and behavioral adaptations and are important pollinators of tropical plants. Despite their diversity and functional importance, their ecology, and especially chemical ecology, has received relatively little attention, particularly compared to their relative the honeybee, Apis mellifera. Here, I review various aspects of the chemical ecology of stingless bees, from communication over resource allocation to defense. I list examples in which functions of specific compounds (or compound groups) have been demonstrated by behavioral experiments, and show that many aspects (e.g., queen-worker interactions, host-parasite interactions, neuronal processing etc.) remain little studied. This review further reveals that the vast majority of studies on the chemical ecology of stingless bees have been conducted in the New World, whereas studies on Old World stingless bees are still comparatively rare. Given the diversity of species, behaviors and, apparently, chemical compounds used, I suggest that stingless bees provide an ideal subject for studying how functional context and the need for species specificity may interact to shape pheromone diversification in social insects.

Animal-Microbial Symbioses in Changing Environments

PubMed Central

Carey, Hannah V.; Duddleston, Khrystyne N.

2014-01-01

The environments in which animals have evolved and live have profound effects on all aspects of their biology. Predictable rhythmic changes in the physical environment are arguably among the most important forces shaping the evolution of behavior and physiology of animals, and to anticipate and prepare for these predictable changes animals have evolved biological clocks. Unpredictable changes in the physical environment have important impacts on animal biology as well. The ability of animals to cope with and survive unpredictable perturbations depends on phenotypic plasticity and/or microevolution. From the time metazoans first evolved from their protistan ancestors they have lived in close association with a diverse array of microbes that have influenced, in some way, all aspects of the evolution of animal structure, function and behavior. Yet, few studies have addressed whether daily or seasonal rhythms may affect, or be affected by, an animal’s microbial symbionts. This survey highlights how biologists interested in the ecological and evolutionary physiology of animals whose lifestyles are influenced by environmental cycles may benefit from considering whether symbiotic microbes have shaped the features they study. PMID:25086977

Photomorphogenic responses to ultraviolet-B light.

PubMed

Jenkins, Gareth I

2017-11-01

Exposure to ultraviolet B (UV-B) light regulates numerous aspects of plant metabolism, morphology and physiology through the differential expression of hundreds of genes. Photomorphogenic responses to UV-B are mediated by the photoreceptor UV RESISTANCE LOCUS8 (UVR8). Considerable progress has been made in understanding UVR8 action: the structural basis of photoreceptor function, how interaction with CONSTITUTIVELY PHOTOMORPHOGENIC 1 initiates signaling and how REPRESSOR OF UV-B PHOTOMORPHOGENESIS proteins negatively regulate UVR8 action. In addition, recent research shows that UVR8 mediates several responses through interaction with other signaling pathways, in particular auxin signaling. Nevertheless, many aspects of UVR8 action remain poorly understood. Most research to date has been undertaken with Arabidopsis, and it is important to explore the functions and regulation of UVR8 in diverse plant species. Furthermore, it is essential to understand how UVR8, and UV-B signaling in general, regulates processes under natural growth conditions. Ultraviolet B regulates the expression of many genes through UVR8-independent pathways, but the activity and importance of these pathways in plants growing in sunlight are poorly understood. © 2017 John Wiley & Sons Ltd.

Riverine Settlement Adaptation Characteristic in Mentaya River, East Kotawaringin Regency, Kalimantan Province

NASA Astrophysics Data System (ADS)

Esariti, L.; Yuliastuti, N.; Ratih, N. K.

2018-02-01

The research looks for the importance of riverine settlement preservation as one of the efforts to carry out sustainable management of a traditional settlement. East Kalimantan, more specifically riverine settlement in Mentaya River is known as one of the traditional settlements that put river as the central of their livelihood activities. The theory of Rapopport [1] was used to investigate the importance of cultural aspect influence to the settlement process, and to seek for the behavioural and environment relationship in determining the pattern of adaptation process. Mix method approach was conducted by utilizing in depth interviews among 40 respondents within three districts, namely in Baamang, Mentaya Seberang and Mentawa Baru Ketapang subdistrict. The result shows that culture dominantly affect the process of settlement adaptation, especially the aspect of family structure, social network, and kinship. The adaptation pattern is influenced significantly by physical environment, type of physical condition of the houses, economic condition and the degree of heritage preservation motive. It sums up that adaptation process could be effective if the integration of culture, activities and government regulations is performed.

Lessons from the Tao for birthing practice.

PubMed

Overman, B

1994-06-01

The metaphysics of the Tao Te Ching, as the basic structure of the universe, is used to examine birthing as creation. Lessons from the Tao regarding cultivating naturalness are drawn upon to provide suggestions for women in preparation for birthing, as well as for the nurses and midwives who attend them. Compatibility of this metaphysical view of birthing with Rogers's and Newman's nursing theories is identified, and the importance of honoring the metaphysical and spiritual aspects of birthing in nursing practice is stressed.

Evaluation of the Implications of Nanoscale Architectures on Contextual Knowledge Discovery and Memory: Self-Assembled Architectures and Memory

DTIC Science & Technology

2008-05-01

patterns. Our strategy to nucleate Ag nanoparticles has been to use a templating protein (e.g., streptavidin) that has been chemically pre- charged with...assembly is used to direct the formation of switching devices and wires to create logic circuitry, memory, and I/O interfaces . We can control the reaction...determines the formation of structures (through complementarity ). Sequence design is important because it determines many aspects of the target DNA

Integrating SHM and Time Variant System Performance of Naval Ship Structures For Near Real Time Decision Making Under Uncertainty: A Comprehensive Framework

DTIC Science & Technology

2016-12-06

direction and speed based on cost minimization and best estimated time of arrival (ETA). Sometimes, ships are forced to travel 43 Lehigh Technical...the allowable time to complete the travel . Another important aspect, addressed in the case study, is to investigate the optimal routing of aged...The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing

State-of-the-art technologies, current opinions and developments, and novel findings: news from the field of histochemistry and cell biology.

PubMed

Asan, Esther; Drenckhahn, Detlev

2008-12-01

Investigations of cell and tissue structure and function using innovative methods and approaches have again yielded numerous exciting findings in recent months and have added important data to current knowledge, inspiring new ideas and hypotheses in various fields of modern life sciences. Topics and contents of comprehensive expert reviews covering different aspects in methodological advances, cell biology, tissue function and morphology, and novel findings reported in original papers are summarized in the present review.

Experimental analysis for fabrication of high-aspect-ratio piezoelectric ceramic structure by micro-powder injection molding process

NASA Astrophysics Data System (ADS)

Han, Jun Sae; Gal, Chang Woo; Park, Jae Man; Kim, Jong Hyun; Park, Seong Jin

2018-04-01

Aspect ratio effects in the micro-powder injection molding process were experimentally analyzed for fabrication of high-aspect-ratio piezoelectric ceramic structure. The mechanisms of critical defects have been studied according to individual manufacturing steps. In the molding process, incomplete filling phenomenon determines the critical aspect ratios of a micro pattern. According to mold temperature, an incomplete filling phenomenon has been analyzed with respect to different pattern sizes and aspect ratio. In demolding and drying process, the capillary behavior of sacrificial polymeric mold insert determines the critical aspect ratio of a micro pattern. With respect to pattern dimensions, slumping behavior has been analyzed. Based on our current systems, micro PZT feature has stability when it has lower aspect ratio than 5. Under optimized processing conditions, 20 μm and 40 μm ceramic rod array feature which has 5 of aspect ratio were successfully fabricated by the developed process. Further modification points to fabricate the smaller and higher feature were specifically addressed.

Political legitimacy and approval of political protest and violence among children and adolescents.

PubMed

Funderburk, C

1975-06-01

A question of general theoretical relevance for political socialization research concerns the role played by basic political orientations in structuring specific political opinions. This report investigates the relationship between beliefs in the legitimacy of political objects and approval of political protest and violence among a sample of children and adolescents. The setting for the research was a Florida town. Four aspects of political legitimacy are defined and measured. Measures of approval of political protest and political violence are distinguished conceptually and empirically. Beliefs in political legitimacy are shown to be of considerable importance in structuring opinions about political violence but have little impact on opinions about protest.

The features of self-assembling organic bilayers important to the formation of anisotropic inorganic materials in microgravity conditions

NASA Technical Reports Server (NTRS)

Talham, Daniel R.; Adair, James H.

2005-01-01

Materials with directional properties are opening new horizons in a variety of applications including chemistry, electronics, and optics. Structural, optical, and electrical properties can be greatly augmented by the fabrication of composite materials with anisotropic microstructures or with anisotropic particles uniformly dispersed in an isotropic matrix. Examples include structural composites, magnetic and optical recording media, photographic film, certain metal and ceramic alloys, and display technologies including flat panel displays. The new applications and the need for model particles in scientific investigations are rapidly out-distancing the ability to synthesize anisotropic particles with specific chemistries and narrowly distributed physical characteristics (e.g. size distribution, shape, and aspect ratio).

Viruses, Artificial Viruses and Virus-Based Structures for Biomedical Applications.

PubMed

van Rijn, Patrick; Schirhagl, Romana

2016-06-01

Nanobiomaterials such as virus particles and artificial virus particles offer tremendous opportunities to develop new biomedical applications such as drug- or gene-delivery, imaging and sensing but also improve understanding of biological mechanisms. Recent advances within the field of virus-based systems give insights in how to mimic viral structures and virus assembly processes as well as understanding biodistribution, cell/tissue targeting, controlled and triggered disassembly or release and circulation times. All these factors are of high importance for virus-based functional systems. This review illustrates advances in mimicking and enhancing or controlling these aspects to a high degree toward delivery and imaging applications. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Beef alliances: motivations, extent, and future prospects.

PubMed

Schroeder, Ted C; Kovanda, Joseph

2003-07-01

With their growth, it is important to consider how alliances will impact the beef industry in the future. Alliances have the potential to make sweeping changes to cattle production, live and feeder cattle marketing, food safety protocols, use of government grades and standards, ownership structure, supply chain management, wholesale and retail product marketing, risk management, and many other industry activities. In an effort to address these issues, this article addresses the following questions: What is an alliance? What has motivated their proliferation? What have we learned from alliances? What aspects of alliances affect their likelihood of success or failure? What is the future of alliances? Are they a fad or a long-term evolving industry structural change?

The economics of end-stage renal disease care in Canada: incentives and impact on delivery of care.

PubMed

Manns, Braden J; Mendelssohn, David C; Taub, Kenneth J

2007-09-01

Examining international differences in health outcomes for end-stage renal disease (ESRD) patients requires an understanding of ESRD funding structures. In Canada, funding for all aspects of dialysis and transplant care, with the exception of drugs (for which supplementary insurance can be purchased), is provided for all citizens. Although ESRD programs across Canada's 10 provinces differ in funding structure, they share important economic characteristics, including being publicly funded and universal, and providing most facets of ESRD care for free. This paper explains how ESRD care fits into the Canadian health care system, describes the epidemiology of ESRD in Canada, and offers economic explanations for international discrepancies.

Physics of protein folding

NASA Astrophysics Data System (ADS)

Finkelstein, A. V.; Galzitskaya, O. V.

2004-04-01

Protein physics is grounded on three fundamental experimental facts: protein, this long heteropolymer, has a well defined compact three-dimensional structure; this structure can spontaneously arise from the unfolded protein chain in appropriate environment; and this structure is separated from the unfolded state of the chain by the “all-or-none” phase transition, which ensures robustness of protein structure and therefore of its action. The aim of this review is to consider modern understanding of physical principles of self-organization of protein structures and to overview such important features of this process, as finding out the unique protein structure among zillions alternatives, nucleation of the folding process and metastable folding intermediates. Towards this end we will consider the main experimental facts and simple, mostly phenomenological theoretical models. We will concentrate on relatively small (single-domain) water-soluble globular proteins (whose structure and especially folding are much better studied and understood than those of large or membrane and fibrous proteins) and consider kinetic and structural aspects of transition of initially unfolded protein chains into their final solid (“native”) 3D structures.

Different Measures of Structural Similarity Tap Different Aspects of Visual Object Processing

PubMed Central

Gerlach, Christian

2017-01-01

The structural similarity of objects has been an important variable in explaining why some objects are easier to categorize at a superordinate level than to individuate, and also why some patients with brain injury have more difficulties in recognizing natural (structurally similar) objects than artifacts (structurally distinct objects). In spite of its merits as an explanatory variable, structural similarity is not a unitary construct, and it has been operationalized in different ways. Furthermore, even though measures of structural similarity have been successful in explaining task and category-effects, this has been based more on implication than on direct empirical demonstrations. Here, the direct influence of two different measures of structural similarity, contour overlap and within-item structural diversity, on object individuation (object decision) and superordinate categorization performance is examined. Both measures can account for performance differences across objects, but in different conditions. It is argued that this reflects differences between the measures in whether they tap: (i) global or local shape characteristics, and (ii) between- or within-category structural similarity. PMID:28861027

Structure and interactions of biological helices

NASA Astrophysics Data System (ADS)

Kornyshev, Alexei A.; Lee, Dominic J.; Leikin, Sergey; Wynveen, Aaron

2007-07-01

Helices are essential building blocks of living organisms, be they molecular fragments of proteins ( α -helices), macromolecules (DNA and collagen), or multimolecular assemblies (microtubules and viruses). Their interactions are involved in packing of meters of genetic material within cells and phage heads, recognition of homologous genes in recombination and DNA repair, stability of tissues, and many other processes. Helical molecules form a variety of mesophases in vivo and in vitro. Recent structural studies, direct measurements of intermolecular forces, single-molecule manipulations, and other experiments have accumulated a wealth of information and revealed many puzzling physical phenomena. It is becoming increasingly clear that in many cases the physics of biological helices cannot be described by theories that treat them as simple, unstructured polyelectrolytes. The present article focuses on the most important and interesting aspects of the physics of structured macromolecules, highlighting various manifestations of the helical motif in their structure, elasticity, interactions with counterions, aggregation, and poly- and mesomorphic transitions.

Fuzzy Edge Connectivity of Graphical Fuzzy State Space Model in Multi-connected System

NASA Astrophysics Data System (ADS)

Harish, Noor Ainy; Ismail, Razidah; Ahmad, Tahir

2010-11-01

Structured networks of interacting components illustrate complex structure in a direct or intuitive way. Graph theory provides a mathematical modeling for studying interconnection among elements in natural and man-made systems. On the other hand, directed graph is useful to define and interpret the interconnection structure underlying the dynamics of the interacting subsystem. Fuzzy theory provides important tools in dealing various aspects of complexity, imprecision and fuzziness of the network structure of a multi-connected system. Initial development for systems of Fuzzy State Space Model (FSSM) and a fuzzy algorithm approach were introduced with the purpose of solving the inverse problems in multivariable system. In this paper, fuzzy algorithm is adapted in order to determine the fuzzy edge connectivity between subsystems, in particular interconnected system of Graphical Representation of FSSM. This new approach will simplify the schematic diagram of interconnection of subsystems in a multi-connected system.

A cognitive developmental approach to variability in the psychotherapeutic process with adolescents.

PubMed

Gunning, C; Verheij, F

1990-01-01

Formulated from a cognitive frame of reference, psychodynamic therapy can be viewed as acting on one of the three aspects (feeling, thought, action) in order to influence or change the client's action and thought schemes. In this paper the consequences of the interaction of cognition and emotion for psychotherapeutic practice with adolescents are explored. Knowledge of cognitive development is supposed to be important for the therapist because, from Piaget's viewpoint, the structures of affect are cognitive structures. Moreover a great variability exists in cognitive development between adolescents. This variability is due to individual, family and social variables. The cognitive structural developmental model, the relation between emotional and cognitive development and the afore-mentioned variables are discussed. Consequences are psychotherapeutic practice with adolescents are described and short case histories are given. The authors conclude that in psychotherapeutic practice psychodynamic theory and cognitive structural theory can complete each other.

Static characteristics design of hydrostatic guide-ways based on fluid-structure interactions

NASA Astrophysics Data System (ADS)

Lin, Shuo; Yin, YueHong

2016-10-01

With the raising requirements in micro optical systems, the available machines become hard to achieve the process dynamic and accuracy in all aspects. This makes compact design based on fluid/structure interactions (FSI) important. However, there is a difficulty in studying FSI with oil film as fluid domain. This paper aims at static characteristic design of a hydrostatic guide-way with capillary restrictors based on FSI. The pressure distribution of the oil film land is calculated by solving the Reynolds-equation with Galerkin technique. The deformation of structure is calculated by commercial FEM software, MSC. Nastran. A matlab program is designed to realize the coupling progress by modifying the load boundary in the submitting file and reading the deformation result. It's obvious that the stiffness of the hydrostatic bearing decreases with the weakening of the bearing structure. This program is proposed to make more precise prediction of bearing stiffness.

An Overview of Biological Macromolecule Crystallization

PubMed Central

Krauss, Irene Russo; Merlino, Antonello; Vergara, Alessandro; Sica, Filomena

2013-01-01

The elucidation of the three dimensional structure of biological macromolecules has provided an important contribution to our current understanding of many basic mechanisms involved in life processes. This enormous impact largely results from the ability of X-ray crystallography to provide accurate structural details at atomic resolution that are a prerequisite for a deeper insight on the way in which bio-macromolecules interact with each other to build up supramolecular nano-machines capable of performing specialized biological functions. With the advent of high-energy synchrotron sources and the development of sophisticated software to solve X-ray and neutron crystal structures of large molecules, the crystallization step has become even more the bottleneck of a successful structure determination. This review introduces the general aspects of protein crystallization, summarizes conventional and innovative crystallization methods and focuses on the new strategies utilized to improve the success rate of experiments and increase crystal diffraction quality. PMID:23727935

Towards structural models of molecular recognition in olfactory receptors.

PubMed

Afshar, M; Hubbard, R E; Demaille, J

1998-02-01

The G protein coupled receptors (GPCR) are an important class of proteins that act as signal transducers through the cytoplasmic membrane. Understanding the structure and activation mechanism of these proteins is crucial for understanding many different aspects of cellular signalling. The olfactory receptors correspond to the largest family of GPCRs. Very little is known about how the structures of the receptors govern the specificity of interaction which enables identification of particular odorant molecules. In this paper, we review recent developments in two areas of molecular modelling: methods for modelling the configuration of trans-membrane helices and methods for automatic docking of ligands into receptor structures. We then show how a subset of these methods can be combined to construct a model of a rat odorant receptor interacting with lyral for which experimental data are available. This modelling can help us make progress towards elucidating the specificity of interactions between receptors and odorant molecules.

Effect of hydrostatic pressure on physical properties of strontium based fluoroperovskites for novel applications

NASA Astrophysics Data System (ADS)

Erum, Nazia; Azhar Iqbal, Muhammad

2018-02-01

Density functional theory (DFT) is employed to calculate the effect of pressure variation on electronic structure, elastic parameters, mechanical durability, and thermodynamic aspects of SrRbF3, in combination with Quasi-harmonic Debye model. The pressure effects are determined in the range of 0-25 GPa, in which cubic stability of SrRbF3 fluoroperovskite remains valid. Significant influence of compression on wide range of elastic parameters and related mechanical properties have been discussed, to utilize this material in low birefringence lens fabrication technology. Apart of linear dependence on elastic coefficients, transition from brittle to ductile behavior is also observed at elevated pressure ranges. Moreover, successful prediction of important thermodynamic aspects such as volume expansion coefficient (α), Debye temperature (θ D), heat capacities (Cp and Cv) are also done within wide pressure and temperature ranges.

Event schemas in autism spectrum disorders: the role of theory of mind and weak central coherence.

PubMed

Loth, Eva; Gómez, Juan Carlos; Happé, Francesca

2008-03-01

Event schemas (generalized knowledge of what happens at common real-life events, e.g., a birthday party) are an important cognitive tool for social understanding: They provide structure for social experiences while accounting for many variable aspects. Using an event narratives task, this study tested the hypotheses that theory of mind (ToM) deficits and weak central coherence (WCC, a local processing bias) undermine different aspects of event knowledge in people with autism spectrum disorder (ASD). Event narratives of ASD ToM-failers were overall significantly impaired. ASD ToM-passers showed more specific abnormalities relating to variable activities, and some of these were significantly associated to WCC. Abnormalities in event knowledge might help linking ASD-typical social deficits in real-life situations and the adherence to inflexible routines.

Exploring the Relationship Between Professional Commitment and Job Satisfaction Among Nurses.

PubMed

Hsu, Hsiu-Chin; Wang, Pao-Yu; Lin, Li-Hui; Shih, Whei-Mei; Lin, Mei-Hsiang

2015-09-01

This cross-sectional study explored the relationship between professional commitment and job satisfaction among nurses. A total of 132 registered nurses were recruited from a hospital in northern Taiwan. A self-reported structured questionnaire was used to collect data. Findings revealed significant differences among nurses in willingness to make an effort and their marital status, appraisal in continuing their careers, job level, and goals and values related to working shifts. Significant differences were found between inner satisfaction and work sector and marital status. Nurses' professional commitment was strongly related to job satisfaction; aspects of professional commitment explained 32% of the variance in job satisfaction. Study results may inform health care institutions about the importance of nurses' job satisfaction and professional commitment so hospital administration can improve these aspects of organizational environment. © 2015 The Author(s).

Polyether complexes of groups 13 and 14.

PubMed

Swidan, Ala'aeddeen; Macdonald, Charles L B

2016-07-21

Notable aspects of the chemistry of complexes of polyether ligands including crown ethers, cryptands, glycols, glymes, and related polyether ligands with heavier group 13 and 14 elements are reviewed with a focus on results from 2005 to the present. The majority of reported polyether complexes contain lead(ii) and thallium(i) but recent breakthroughs in regard to the preparation of low oxidation state reagents of the lighter congeners have allowed for the generation of complexes containing indium(i), gallium(i), germanium(ii), and even silicon(ii). The important roles of ligand size, donor types, and counter anions in regard to the chemical properties of the polyether complexes is highlighted. A particular focus on the structural aspects of the numerous coordination complexes provides a rationale for some of the spectacular contributions that such compounds have made to Modern Main Group Chemistry.

Using Conversation Topics for Predicting Therapy Outcomes in Schizophrenia

PubMed Central

Howes, Christine; Purver, Matthew; McCabe, Rose

2013-01-01

Previous research shows that aspects of doctor-patient communication in therapy can predict patient symptoms, satisfaction and future adherence to treatment (a significant problem with conditions such as schizophrenia). However, automatic prediction has so far shown success only when based on low-level lexical features, and it is unclear how well these can generalize to new data, or whether their effectiveness is due to their capturing aspects of style, structure or content. Here, we examine the use of topic as a higher-level measure of content, more likely to generalize and to have more explanatory power. Investigations show that while topics predict some important factors such as patient satisfaction and ratings of therapy quality, they lack the full predictive power of lower-level features. For some factors, unsupervised methods produce models comparable to manual annotation. PMID:23943658

The interface of protein structure, protein biophysics, and molecular evolution

PubMed Central

Liberles, David A; Teichmann, Sarah A; Bahar, Ivet; Bastolla, Ugo; Bloom, Jesse; Bornberg-Bauer, Erich; Colwell, Lucy J; de Koning, A P Jason; Dokholyan, Nikolay V; Echave, Julian; Elofsson, Arne; Gerloff, Dietlind L; Goldstein, Richard A; Grahnen, Johan A; Holder, Mark T; Lakner, Clemens; Lartillot, Nicholas; Lovell, Simon C; Naylor, Gavin; Perica, Tina; Pollock, David D; Pupko, Tal; Regan, Lynne; Roger, Andrew; Rubinstein, Nimrod; Shakhnovich, Eugene; Sjölander, Kimmen; Sunyaev, Shamil; Teufel, Ashley I; Thorne, Jeffrey L; Thornton, Joseph W; Weinreich, Daniel M; Whelan, Simon

2012-01-01

Abstract The interface of protein structural biology, protein biophysics, molecular evolution, and molecular population genetics forms the foundations for a mechanistic understanding of many aspects of protein biochemistry. Current efforts in interdisciplinary protein modeling are in their infancy and the state-of-the art of such models is described. Beyond the relationship between amino acid substitution and static protein structure, protein function, and corresponding organismal fitness, other considerations are also discussed. More complex mutational processes such as insertion and deletion and domain rearrangements and even circular permutations should be evaluated. The role of intrinsically disordered proteins is still controversial, but may be increasingly important to consider. Protein geometry and protein dynamics as a deviation from static considerations of protein structure are also important. Protein expression level is known to be a major determinant of evolutionary rate and several considerations including selection at the mRNA level and the role of interaction specificity are discussed. Lastly, the relationship between modeling and needed high-throughput experimental data as well as experimental examination of protein evolution using ancestral sequence resurrection and in vitro biochemistry are presented, towards an aim of ultimately generating better models for biological inference and prediction. PMID:22528593

Structure and characteristics of heterogeneous detonation

NASA Astrophysics Data System (ADS)

Nicholls, J. A.; Sichel, M.; Kauffman, C. W.

1983-09-01

The emphasis of this research program centered around the structure of heterogeneous detonation waves, inasmuch as this had been found to be very important to the detonation characteristics of heterogeneous mixtures. On the experimental side, a vertical detonation tube was used wherein liquid fuel drops, all of one size, were generated at the top of the tube and allowed to fall vertically into the desired gaseous mixture. A strong blast wave was transmitted into the mixture through use of an auxiliary shock tube. The propagation of the resultant wave was monitored by pressure switches, pressure transducers, and photography. The low vapor pressure liquid fuel, decane (400 micrometer drop size) was used for most of the experiments. Attention was given to wave structure, wave velocity, and initiation energy. Three atmospheres (100% O2; 40% O2/60% N2; and air) and a number of equivalence ratios were investigated. Holographic pictures and streak photography were employed to study the drop shattering process and the structure of the front. Other experiments investigated the addition of the sensitizer, normal propyl nitrate (NPN), to the decane. The important aspect of vapor pressure was studied by heating the entire tube to various elevated temperatures and then noting the effect on detonability.

Structural Connectivity Networks of Transgender People

PubMed Central

Hahn, Andreas; Kranz, Georg S.; Küblböck, Martin; Kaufmann, Ulrike; Ganger, Sebastian; Hummer, Allan; Seiger, Rene; Spies, Marie; Winkler, Dietmar; Kasper, Siegfried; Windischberger, Christian; Swaab, Dick F.; Lanzenberger, Rupert

2015-01-01

Although previous investigations of transsexual people have focused on regional brain alterations, evaluations on a network level, especially those structural in nature, are largely missing. Therefore, we investigated the structural connectome of 23 female-to-male (FtM) and 21 male-to-female (MtF) transgender patients before hormone therapy as compared with 25 female and 25 male healthy controls. Graph theoretical analysis of whole-brain probabilistic tractography networks (adjusted for differences in intracranial volume) showed decreased hemispheric connectivity ratios of subcortical/limbic areas for both transgender groups. Subsequent analysis revealed that this finding was driven by increased interhemispheric lobar connectivity weights (LCWs) in MtF transsexuals and decreased intrahemispheric LCWs in FtM patients. This was further reflected on a regional level, where the MtF group showed mostly increased local efficiencies and FtM patients decreased values. Importantly, these parameters separated each patient group from the remaining subjects for the majority of significant findings. This work complements previously established regional alterations with important findings of structural connectivity. Specifically, our data suggest that network parameters may reflect unique characteristics of transgender patients, whereas local physiological aspects have been shown to represent the transition from the biological sex to the actual gender identity. PMID:25217469

Predicting landslide vegetation in patches on landscape gradients in Puerto Rico

USGS Publications Warehouse

Myster, R.W.; Thomlinson, J.R.; Larsen, M.C.

1997-01-01

We explored the predictive value of common landscape characteristics for landslide vegetative stages in the Luquillo Experimental Forest of Puerto Rico using four different analyses. Maximum likelihood logistic regression showed that aspect, age, and substrate type could be used to predict vegetative structural stage. In addition it showed that the structural complexity of the vegetation was greater in landslides (1) facing the southeast (away from the dominant wind direction of recent hurricanes), (2) that were older, and (3) that had volcaniclastic rather than dioritic substrate. Multiple regression indicated that both elevation and age could be used to predict the current vegetation, and that vegetation complexity was greater both at lower elevation and in older landslides. Pearson product-moment correlation coefficients showed that (1) the presence of volcaniclastic substrate in landslides was negatively correlated with aspect, age, and elevation, (2) that road association and age were positively correlated, and (3) that slope was negatively correlated with area. Finally, principal components analysis showed that landslides were differentiated on axes defined primarily by age, aspect class, and elevation in the positive direction, and by volcaniclastic substrate in the negative direction. Because several statistical techniques indicated that age, aspect, elevation, and substrate were important in determining vegetation complexity on landslides, we conclude that landslide succession is influenced by variation in these landscape traits. In particular, we would expect to find more successional development on landslides which are older, face away from hurricane winds, are at lower elevation, and are on volcaniclastic substrate. Finally, our results lead into a hierarchical conceptual model of succession on landscapes where the biota respond first to either gradients or disturbance depending on their relative severity, and then to more local biotic mechanisms such as dispersal, predation and competition.

Principles of Emergency Department facility design for optimal management of mass-casualty incidents.

PubMed

Halpern, Pinchas; Goldberg, Scott A; Keng, Jimmy G; Koenig, Kristi L

2012-04-01

The Emergency Department (ED) is the triage, stabilization and disposition unit of the hospital during a mass-casualty incident (MCI). With most EDs already functioning at or over capacity, efficient management of an MCI requires optimization of all ED components. While the operational aspects of MCI management have been well described, the architectural/structural principles have not. Further, there are limited reports of the testing of ED design components in actual MCI events. The objective of this study is to outline the important infrastructural design components for optimization of ED response to an MCI, as developed, implemented, and repeatedly tested in one urban medical center. In the authors' experience, the most important aspects of ED design for MCI have included external infrastructure and promoting rapid lockdown of the facility for security purposes; an ambulance bay permitting efficient vehicle flow and casualty discharge; strategic placement of the triage location; patient tracking techniques; planning adequate surge capacity for both patients and staff; sufficient command, control, communications, computers, and information; well-positioned and functional decontamination facilities; adequate, well-located and easily distributed medical supplies; and appropriately built and functioning essential services. Designing the ED to cope well with a large casualty surge during a disaster is not easy, and it may not be feasible for all EDs to implement all the necessary components. However, many of the components of an appropriate infrastructural design add minimal cost to the normal expenditures of building an ED. This study highlights the role of design and infrastructure in MCI preparedness in order to assist planners in improving their ED capabilities. Structural optimization calls for a paradigm shift in the concept of structural and operational ED design, but may be necessary in order to maximize surge capacity, department resilience, and patient and staff safety.

Numerical simulation and experimental validation of Lamb wave propagation behavior in composite plates

NASA Astrophysics Data System (ADS)

Kim, Sungwon; Uprety, Bibhisha; Mathews, V. John; Adams, Daniel O.

2015-03-01

Structural Health Monitoring (SHM) based on Acoustic Emission (AE) is dependent on both the sensors to detect an impact event as well as an algorithm to determine the impact location. The propagation of Lamb waves produced by an impact event in thin composite structures is affected by several unique aspects including material anisotropy, ply orientations, and geometric discontinuities within the structure. The development of accurate numerical models of Lamb wave propagation has important benefits towards the development of AE-based SHM systems for impact location estimation. Currently, many impact location algorithms utilize the time of arrival or velocities of Lamb waves. Therefore the numerical prediction of characteristic wave velocities is of great interest. Additionally, the propagation of the initial symmetric (S0) and asymmetric (A0) wave modes is important, as these wave modes are used for time of arrival estimation. In this investigation, finite element analyses were performed to investigate aspects of Lamb wave propagation in composite plates with active signal excitation. A comparative evaluation of two three-dimensional modeling approaches was performed, with emphasis placed on the propagation and velocity of both the S0 and A0 wave modes. Results from numerical simulations are compared to experimental results obtained from active AE testing. Of particular interest is the directional dependence of Lamb waves in quasi-isotropic carbon/epoxy composite plates. Numerical and experimental results suggest that although a quasi-isotropic composite plate may have the same effective elastic modulus in all in-plane directions, the Lamb wave velocity may have some directional dependence. Further numerical analyses were performed to investigate Lamb wave propagation associated with circular cutouts in composite plates.

Some technical writing skills industry needs

NASA Technical Reports Server (NTRS)

Smith, F. R.

1981-01-01

It is suggested that engineers and other technical students be taught three classes of skills in technical writing. First, "Big Picture Things", which includes: the importance of clear writing, the wide scope of writing, the wide scope of writing tasks that will be faced in industry, and the principles of organization of technical materials such as; how to analyze, classify, partition, and interpret. Second, "Writing Procedures", which encompasses: how to get words on paper efficiently and team-write. Third, "Writing Details", in which two considerations are important: how to achieve precision in the use of language and the aspects of style. Three problems in style are cited: the problem of sentence transition, overuse of attributive adjectives, and verbosity in paragraph structure. The most important thing in technical writing is considered to be functionality, economy and clarity.

A Massively Parallel Particle Code for Rarefied Ionized and Neutral Gas Flows in Earth and Planetary Atmospheres, Ionospheres and Magnetospheres

NASA Technical Reports Server (NTRS)

Combi, Michael R.

2004-01-01

In order to understand the global structure, dynamics, and physical and chemical processes occurring in the upper atmospheres, exospheres, and ionospheres of the Earth, the other planets, comets and planetary satellites and their interactions with their outer particles and fields environs, it is often necessary to address the fundamentally non-equilibrium aspects of the physical environment. These are regions where complex chemistry, energetics, and electromagnetic field influences are important. Traditional approaches are based largely on hydrodynamic or magnetohydrodynamic MHD) formulations and are very important and highly useful. However, these methods often have limitations in rarefied physical regimes where the molecular collision rates and ion gyrofrequencies are small and where interactions with ionospheres and upper neutral atmospheres are important.

Finite-element modeling of the human neurocranium under functional anatomical aspects.

PubMed

Mall, G; Hubig, M; Koebke, J; Steinbuch, R

1997-08-01

Due to its functional significance the human skull plays an important role in biomechanical research. The present work describes a new Finite-Element model of the human neurocranium. The dry skull of a middle-aged woman served as a pattern. The model was developed using only the preprocessor (Mentat) of a commercial FE-system (Marc). Unlike that of other FE models of the human skull mentioned in the literature, the geometry in this model was designed according to functional anatomical findings. Functionally important morphological structures representing loci minoris resistentiae, especially the foramina and fissures of the skull base, were included in the model. The results of two linear static loadcase analyses in the region of the skull base underline the importance of modeling from the functional anatomical point of view.

Improved design of tunnel supports. volume 2: aspects of yielding in ground-structure interaction

DOT National Transportation Integrated Search

1980-06-30

Volume 2 focuses on a particularly complex and often misunderstood aspect of ground-structure interaction, which is ground yielding and loosening, and reports new findings in this area. The findings are based on previous research, on the knowledge ga...

Three Essays on Bureaucracy at American Research Universities

ERIC Educational Resources Information Center

Taggart, Gabel

2017-01-01

The three essays in this dissertation each examine how aspects of contemporary administrative structure within American research universities affect faculty outcomes. Specific aspects of administrative structure tested in this dissertation include the introduction of new administrative roles, administrative intensity (i.e., relative size of…

New perspectives on potential hydrogen storage materials using high pressure.

PubMed

Song, Yang

2013-09-21

In addressing the global demand for clean and renewable energy, hydrogen stands out as the most suitable candidate for many fuel applications that require practical and efficient storage of hydrogen. Supplementary to the traditional hydrogen storage methods and materials, the high-pressure technique has emerged as a novel and unique approach to developing new potential hydrogen storage materials. Static compression of materials may result in significant changes in the structures, properties and performance that are important for hydrogen storage applications, and often lead to the formation of unprecedented phases or complexes that have profound implications for hydrogen storage. In this perspective article, 22 types of representative potential hydrogen storage materials that belong to four major classes--simple hydride, complex hydride, chemical hydride and hydrogen containing materials--were reviewed. In particular, their structures, stabilities, and pressure-induced transformations, which were reported in recent experimental works together with supporting theoretical studies, were provided. The important contextual aspects pertinent to hydrogen storage associated with novel structures and transitions were discussed. Finally, the summary of the recent advances reviewed and the insight into the future research in this direction were given.

Fabrication of silicon-embedded low resistance high-aspect ratio planar copper microcoils

NASA Astrophysics Data System (ADS)

Syed Mohammed, Zishan Ali; Puiu, Poenar Daniel; Aditya, Sheel

2018-01-01

Low resistance is an important requirement for microcoils which act as a signal receiver to ensure low thermal noise during signal detection. High-aspect ratio (HAR) planar microcoils entrenched in blind silicon trenches have features that make them more attractive than their traditional counterparts employing electroplating through a patterned thick polymer or achieved through silicon vias. However, challenges met in fabrication of such coils have not been discussed in detail until now. This paper reports the realization of such HAR microcoils embedded in Si blind trenches, fabricated with a single lithography step by first etching blind trenches in the silicon substrate with an aspect ratio of almost 3∶1 and then filling them up using copper electroplating. The electroplating was followed by chemical wet etching as a faster way of removing excess copper than traditional chemical mechanical polishing. Electrical resistance was further reduced by annealing the microcoils. The process steps and challenges faced in the realization of such structures are reported here followed by their electrical characterization. The obtained electrical resistances are then compared with those of other similar microcoils embedded in blind vias.

Phenolic compounds can delay the oxidation of polyunsaturated fatty acids and the growth of Listeria monocytogenes: structure-activity relationships.

PubMed

Pernin, Aurélia; Dubois-Brissonnet, Florence; Roux, Stéphanie; Masson, Marine; Bosc, Véronique; Maillard, Marie-Noëlle

2018-04-20

Phenolic compounds present a potential solution to ensuring food quality and safety. Indeed, they can limit oxidation reactions and bacterial growth in food products. Although their antioxidant mechanisms of action are well known, their antibacterial ones are less well understood, especially in light of their chemical structures. The aim of this study was to first quantify both aspects of a series of natural phenolic compounds and then link these activities to their chemical structure. We evaluated antioxidant activity by measuring the capacity of phenolic compounds to delay free linoleic acid oxidation caused by the action of a hydrophilic azo-radical initiator (AAPH). We evaluated antibacterial activity by measuring the growth inhibition of Listeria monocytogenes and determining the non-inhibitory and minimum inhibitory concentrations for each compound. Compounds with ortho-diphenolic structures were the best antioxidants, whereas those belonging to the simple phenol category were the best antibacterial compounds. The physico-chemical properties of the compounds influenced both activities, but not in the same way. The chemical environment of the phenolic group and the presence of delocalization structures are the most important parameters for antioxidant activity, whereas the partition coefficient logP is one of the most important factors involved in antibacterial activity. This article is protected by copyright. All rights reserved.

Tree community variation in a tropical continental island according to slope aspect and human interference.

PubMed

Gonçalves, Nathan B; Nettesheim, Felipe C; Conde, Marilena M S

2018-01-01

Associating description of unrecorded tropical tree community structure to sampling approaches that can help determine mechanisms behind floristic variation is important to further the comprehension of how plant species coexist at tropical forests. Thus, this study had the goals of (i) evaluating tree community structure on the continental island of Marambaia (23°4'37.09"S; 43°59'2.15"W) and (ii) testing the prediction that there are local scale changes in a tropical tree community structure between slopes facing different geographic orientation and with distinct human interference history. We established 60 (0.6 ha) sampling units in three different slope sites with distinct predominant geographic orientation and human interference. We sampled all woody trees with diameter at breast height (dbh) ≥ 5 cm. We found a total of 1.170 individuals representing 220 species, 120 genera and 50 families. The overall tree community structure and structural descriptors (abundance of individuals, basal area, species richness and diversity) varied extensively between the sites. The evidence presented here supports that local scale topography variations and human interference history can be important factors contributing to the known floristic heterogeneity of the Atlantic Rainforest. Future work on the study area should focus on disentangling effects from distinct causal factors over tree community variation and species occurrence.

Probing the Complexities of Structural Changes in Layered Oxide Cathode Materials for Li-Ion Batteries during Fast Charge–Discharge Cycling and Heating

DOE PAGES

Hu, Enyuan; Wang, Xuelong; Yu, Xiqian; ...

2018-01-19

The rechargeable lithium-ion battery (LIB) is the most promising energy storage system to power electric vehicles with high energy density and long cycling life. However, in order to meet customers’ demands for fast charging, the power performances of current LIBs need to be improved. From the cathode aspect, layer-structured cathode materials are widely used in today’s market and will continue to play important roles in the near future. The high rate capability of layered cathode materials during charging and discharging is critical to the power performance of the whole cell and the thermal stability is closely related to the safetymore » issues. Therefore, the in-depth understanding of structural changes of layered cathode materials during high rate charging/discharging and the thermal stability during heating are essential in developing new materials and improving current materials. Since structural changes take place from the atomic level to the whole electrode level, combination of characterization techniques covering multilength scales is quite important. Finally, in many cases, this means using comprehensive tools involving diffraction, spectroscopy, and imaging to differentiate the surface from the bulk and to obtain structural/chemical information with different levels of spatial resolution.« less

Therapeutic risk management of the suicidal patient: augmenting clinical suicide risk assessment with structured instruments.

PubMed

Homaifar, Beeta; Matarazzo, Bridget; Wortzel, Hal S

2013-09-01

This column is the second in a series presenting a model for therapeutic risk management of the suicidal patient. As discussed in the first part of the series, the model involves several elements including augmenting clinical risk assessment with structured instruments, stratifying risk in terms of both severity and temporality, and developing and documenting a safety plan. This column explores in more detail how to augment clinical risk assessment with structured instruments. Unstructured clinical interviews have the potential to miss important aspects of suicide risk assessment. By augmenting the free-form clinical interview with structured instruments that demonstrate reliability and validity, a more nuanced and multifaceted approach to suicide risk assessment is achieved. Incorporating structured instruments into practice also serves a medicolegal function, since these instruments may become a living part of the medical record, establishing baseline levels of suicidal thoughts and behaviors and facilitating future clinical determinations regarding safety needs. We describe several instruments used in a multidisciplinary suicide consultation service, each of which has demonstrated relevance to suicide risk assessment and screening, ease of administration, and strong psychometric properties. In addition, we emphasize the importance of viewing suicide risk assessment as an ongoing process rather than as a singular event. Finally, we discuss special considerations in the evolving practice of risk assessment.

Inclusiveness and crossed categorization: effects on co-joined category evaluations of in-group and out-group primes.

PubMed

Crisp, Richard J; Hewstone, Miles; Richards, Zoë; Paolini, Stefania

2003-03-01

This experiment builds on preliminary work (Crisp & Hewstone, 2000b) that revealed moderation of crossed-category evaluations via priming with an in-group inclusive pronoun (e.g. 'we'). Using a computerized minimal group classification procedure and a 'proofreading' priming task, participants were asked to evaluate different crossed-category groups following either a neutral, an inclusive (in-group), or an exclusive (out-group) prime. The results supported the notion that inclusiveness priming can moderate how perceivers represent and evaluate composite social groups. In addition, measures of perceived inclusiveness and importance suggested that such structural aspects of social categories are an important consideration for future multiple categorization work.

Protein crystallography for non-crystallographers, or how to get the best (but not more) from published macromolecular structures

PubMed Central

Wlodawer, Alexander; Minor, Wladek; Dauter, Zbigniew; Jaskolski, Mariusz

2015-01-01

The number of macromolecular structures deposited in the Protein Data Bank now exceeds 45 000, with the vast majority determined using crystallographic methods. Thousands of studies describing such structures have been published in the scientific literature, and 14 Nobel prizes in chemistry or medicine have been awarded to protein crystallographers. As important as these structures are for understanding the processes that take place in living organisms and also for practical applications such as drug design, many non-crystallographers still have problems with critical evaluation of the structural literature data. This review attempts to provide a brief outline of technical aspects of crystallography and to explain the meaning of some parameters that should be evaluated by users of macromolecular structures in order to interpret, but not over-interpret, the information present in the coordinate files and in their description. A discussion of the extent of the information that can be gleaned from the coordinates of structures solved at different resolution, as well as problems and pitfalls encountered in structure determination and interpretation are also covered. PMID:18034855

Vegetation Structure of Ebony Leaf Monkey (Trachypithecus auratus) Habitat in Kecubung Ulolanang Nature Preservation Central Java-Indonesia

NASA Astrophysics Data System (ADS)

Ervina, Rahmawati; Wasiq, Hidayat Jafron

2018-02-01

Kecubung Ulolanang Nature Preservation is ebony leaf monkey's habitats in Central Java Indonesia. Continuously degradation of their population is caused by illegal hunting and habitat degradation that made this species being vulnerable. Habitat conservation is one of important aspects to prevent them from extinction. The purpose of this research was to analyze the vegetation's structure and composition, which was potentially, becomes habitat and food source for the monkeys. Data collected using purposive sampling with line transect method of four different level of vegetation. Data analysis used Important Value Index and Diversity Index. There were 43 species of vegetation at seedling stage, 18 species at sapling stage, 8 species at poles stage and 27 species at trees stage. Species that had the highest important value index at seedling was Stenochlaena palustri , at the sapling was Gnetum gnemon, at pole was Swietenia mahagoni and at tree was Tectona grandis . Species of trees those were potentially to become habitat (food source) for ebony leaf monkey were T. grandis, Dipterocarpus gracilis, Quercus sundaica and Ficus superba. The highest diversity index was at seedling gwoth stage.

Valued aspects of primary palliative care: content analysis of bereaved carers' descriptions.

PubMed

Grande, Gunn E; Farquhar, Morag C; Barclay, Stephen Ig; Todd, Chris J

2004-10-01

Informal carers provide the bulk of palliative home care. They largely rely on general practitioners (GPs) and district nurses to support them in this role, yet little is known about what carers themselves consider important in this support. To identify what informal carers valued in the palliative support provided by GPs and district nurses by using carers' own descriptions of such support. Retrospective interviews. Primary care in Cambridgeshire. Semi-structured interviews with bereaved carers of 48 patients with cancer and 12 patients with non-cancer diagnoses. Content analysis of carers' evaluative descriptions of GP and district nurse support. The accessibility of the GP and district nurse emerged as the most important aspect of support. Enlistment of help from other agencies was also extensively mentioned, together with provision of equipment. Attitude or approach during interactions, and relationship with the professional were important, particularly regarding GP support, whereas support for the carer, information, and symptom control were mentioned less often. Data suggested that support was not as good for older patients (> or =75 years), but this finding requires further investigation. Results largely confirmed findings of previous, quantitative research and the importance of a patient-centred approach. What emerged most strongly, however, was the central importance of accessibility of support services for lay carers responsible for end-of-life home care. This mainly concerned GP and district nurse support, but accessibility of additional care and equipment were also important. In short, carers' main focus was the basic support that enabled them to sustain care in the home.

Structure of the kinase domain of Gilgamesh from Drosophila melanogaster

PubMed Central

Han, Ni; Chen, CuiCui; Shi, Zhubing; Cheng, Dianlin

2014-01-01

The CK1 family kinases regulate multiple cellular aspects and play important roles in Wnt/Wingless and Hedgehog signalling. The kinase domain of Drosophila Gilgamesh isoform I (Gilgamesh-I), a homologue of human CK1-γ, was purified and crystallized. Crystals of methylated Gilgamesh-I kinase domain with a D210A mutation diffracted to 2.85 Å resolution and belonged to space group P43212, with unit-cell parameters a = b = 52.025, c = 291.727 Å. The structure of Gilgamesh-I kinase domain, which was determined by molecular replacement, has conserved catalytic elements and an active conformation. Structural comparison indicates that an extended loop between the α1 helix and the β4 strand exists in the Gilgamesh-I kinase domain. This extended loop may regulate the activity and function of Gilgamesh-I. PMID:24699734

Distribution of Lepidopteran Larvae on Norway Spruce: Effects of Slope and Crown Aspect.

PubMed

Kulfan, Ján; Dvořáčková, Katarína; Zach, Peter; Parák, Michal; Svitok, Marek

2016-04-01

Lepidoptera associated with Norway spruce, Picea abies (L.) Karsten, play important roles in ecosystem processes, acting as plant pests, prey for predators, and hosts for parasites and parasitoids. Their distribution patterns in spruce crowns and forests are only poorly understood. We examined how slope and crown aspect affect the occurrence and abundance of moth larvae on solitary spruce trees in a montane region in Central Europe. Moth larvae were collected from southern and northern crowns of trees growing on south- and north-facing slopes (four treatments) using emergence boxes at the end of winter and by the beating method during the growing season. Species responses to slope and crown aspect were not uniform. Treatment effects on moth larvae were stronger in the winter than during the growing season. In winter, the abundance of bud-boring larvae was significantly higher in northern than in southern crowns regardless of the slope aspect, while both slope and aspect had marginally significant effects on abundance of miners. During the growing season, the occurrence of free-living larvae was similar among treatments. Emergence boxes and beating spruce branches are complementary techniques providing valuable insights into the assemblage structure of moth larvae on Norway spruce. Due to the uneven distribution of larvae detected in this study, we recommend adoption of a protocol that explicitly includes sampling of trees from contrasting slopes and branches from contrasting crown aspect in all seasons. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

On the influence of frequency-dependent elastic properties in vibro-acoustic modelling of porous materials under structural excitation

NASA Astrophysics Data System (ADS)

Van der Kelen, C.; Göransson, P.; Pluymers, B.; Desmet, W.

2014-12-01

The aspects related to modelling the frequency dependence of the elastic properties of air-saturated porous materials have been largely neglected in the past for several reasons. For acoustic excitation of porous materials, the material behaviour can be quite well represented by models where the properties of the solid frame have little influence. Only recently has the importance of the dynamic moduli of the frame come into focus. This is related to a growing interest in the material behaviour due to structural excitation. Two aspects stand out in connection with the elastic-dynamic behaviour. The first is related to methods for the characterisation of the dynamic moduli of porous materials. The second is a perceived lack of numerical methods able to model the complex material behaviour under structural excitation, in particular at higher frequencies. In the current paper, experimental data from a panel under structural excitation, coated with a porous material, are presented. In an attempt to correlate the experimental data to numerical predictions, it is found that the measured quasi-static material parameters do not suffice for an accurate prediction of the measured results. The elastic material parameters are then estimated by correlating the numerical prediction to the experimental data, following the physical behaviour predicted by the augmented Hooke's law. The change in material behaviour due to the frequency-dependent properties is illustrated in terms of the propagation of the slow wave and the shear wave in the porous material.

Program structure-based blocking

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

Bertolli, Carlo; Eichenberger, Alexandre E.; O'Brien, John K.

2017-09-26

Embodiments relate to program structure-based blocking. An aspect includes receiving source code corresponding to a computer program by a compiler of a computer system. Another aspect includes determining a prefetching section in the source code by a marking module of the compiler. Yet another aspect includes performing, by a blocking module of the compiler, blocking of instructions located in the prefetching section into instruction blocks, such that the instruction blocks of the prefetching section only contain instructions that are located in the prefetching section.

Chapter 1: A Brief Introduction to Lignin Structure

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

Katahira, Rui; Beckham, Gregg T; Elder, Thomas J.

Lignin is an alkyl-aromatic polymer found in the cell walls of terrestrial plants. Lignin provides structure and rigidity to plants, is a natural, highly effective barrier against microbial attack, and enables water and nutrient transport through plant tissues. Depending on the plant species, the constituents of lignin can vary considerably, leading to substantial diversity in lignin chemistry and structure. Despite nearly a century of research and development attempting to convert lignin into valuable products, lignin in most current and planned biorefinery contexts remains underutilized, most often being burned to generate heat and power. However, the drive towards effective lignin valorizationmore » processes has witnessed a significant resurgence in the past decade, catalyzed by advances in improved understanding of lignin chemistry, structure, and plasticity in parallel with new catalytic and biological approaches to valorize this important, prevalent biopolymer. As a preface to the subsequent chapters in this book, this chapter briefly highlights the known aspects of lignin structure.« less

Thermodynamics of water structural reorganization due to geometric confinement

NASA Astrophysics Data System (ADS)

Stroberg, Wylie; Lichter, Seth

2015-03-01

Models of aqueous solvation have successfully quantified the behavior of water near convex bodies. However, many important processes occurring in aqueous solution involve interactions between solutes and surfaces with complicated non-convex geometries. Examples include the folding of proteins, hydrophobic association of solutes, ligand-receptor binding, and water confined within nanotubes and pores. For these geometries, models for solvation of convex bodies fail to account for the added interactions associated with structural confinement. Due to water's propensity to form networks of hydrogen bonds, small alterations to the confining geometry can induce large structural rearrangement within the water. We perform systematic Monte Carlo simulations of water confined to cylindrical cavities of varying aspect ratio to investigate how small geometric changes to the confining geometry may cause large changes to the structure and thermodynamic state of water. Using the Wang-Landau algorithm, we obtain free energies, enthalpies, entropies, and heat capacities across a broad range of temperatures, and show how these quantities are influenced by the structural rearrangement of water molecules due to geometric perturbations.

Methodologies of Research into Gender and Other Social Differences within a Multi-Faceted Conception of Social Justice

ERIC Educational Resources Information Center

Evans, Jeff; Tsatsaroni, Anna

2008-01-01

Our discussion of social justice begins by embracing both "distribution" and "recognition" aspects of social relations (Vincent, 2003). The first aspect considers the way that goods, knowledge, skills, rights, etc. are distributed among social groups; the second aspect focuses on aspects of society structuring social encounters…

Development of a method for rating climate seat comfort

NASA Astrophysics Data System (ADS)

Scheffelmeier, M.; Classen, E.

2017-10-01

The comfort aspect in the vehicle interior is becoming increasingly important. A high comfort level offers the driver a good and secure feeling and has a strong influence on passive traffic safety. One important part of comfort is the climate aspect, especially the microclimate that emerges between passenger and seat. In this research, different combinations of typical seat materials are used. Fourteen woven and knitted fabrics and eight leathers and its substitutes for the face fabric layer, one foam, one non-woven and one 3D spacer for the plus pad layer and for the support layer three foam types with variations in structure and raw material as well as one rubber hair structure were investigated. To characterise this sample set by thermo-physiological aspects (e.g. water vapour resistance Ret, thermal resistance Rct, buffering capacity of water vapour Fd) regular and modified sweating guarded hotplates were used according to DIN EN ISO 11092. The results of the material characterisation confirm the common knowledge that seat covers out of textiles have better water vapour resistance values than leathers and its substitutes. Subject trials in a driving simulator were executed to rate the subjective sensation while driving in a vehicle seat. With a thermal, sweating Manikin (Newton Type, Thermetrics) objective product measurements were carried out on the same seat. Indeed the subject trials show that every test subject has his or her own subjective perception concerning the climate comfort. The results of the subject trials offered the parameters for the Newton measuring method. Respectively the sweating rate, sit-in procedure, ambient conditions and sensor positions on and between the seat layers must be comparable with the subject trials. By taking care of all these parameters it is possible to get repeatable and reliable results with the Newton Manikin. The subjective feelings of the test subjects, concerning the microclimate between seat and passenger, provide the evaluation of the Manikins output (Rc and Re values).

Nominal and Verbal Semantic Structure: Analogies and Interactions.

ERIC Educational Resources Information Center

Filip, Hanna

2001-01-01

Examines parallels in semantic structure between noun phrases and verbal predicates in constructions in which they are mutually constraining and contribute to the expression of lexical aspect and grammatical aspect. Data are drawn mainly from English and Slavic languages, which are compared to German and Finnish. (Author/VWL)

Relaxation and physical aging in network glasses: a review.

PubMed

Micoulaut, Matthieu

2016-06-01

Recent progress in the description of glassy relaxation and aging are reviewed for the wide class of network-forming materials such as GeO2, Ge x Se1-x , silicates (SiO2-Na2O) or borates (B2O3-Li2O), all of which have an important usefulness in domestic, geological or optoelectronic applications. A brief introduction of the glass transition phenomenology is given, together with the salient features that are revealed both from theory and experiments. Standard experimental methods used for the characterization of the slowing down of the dynamics are reviewed. We then discuss the important role played by aspects of network topology and rigidity for the understanding of the relaxation of the glass transition, while also permitting analytical predictions of glass properties from simple and insightful models based on the network structure. We also emphasize the great utility of computer simulations which probe the dynamics at the molecular level, and permit the calculation of various structure-related functions in connection with glassy relaxation and the physics of aging which reveal the non-equilibrium nature of glasses. We discuss the notion of spatial variations of structure which leads to the concept of 'dynamic heterogeneities', and recent results in relation to this important topic for network glasses are also reviewed.

Medical Tourism in Malaysia: Prospect and Challenges.

PubMed

Sarwar, Abdullah

2013-08-01

Tourism, combined with the phrase medical, seems to be a new form of tourism which has gained huge popularity in recent decades. Though, a number of literatures available with regard to the tourism industry and the competitiveness of the destination, however, the major aspects which determine the satisfaction of medical tourists are hardly focused specifically on Malaysia. There is a lack of empirical evidence in this area of study which needs to be bridged. Hence, this study aimed at investigating the various factors contributing towards the development of medical tourism in Malaysia. As the purpose of the research was to find out various factors contributing towards the development of medical tourism in Malaysia, so this study used Structural Equation modeling (SEM) for data analysis. The target population for this study consisted of the medical tourists coming to Malaysia with the primary intension of seeking medical procedures other than sightseeing. A total sample size of 266 was collected through non-probability judgment sampling during the period between December 2012 and February 2013. The result confirms that destination competitiveness and service quality play an important role in the medical tourist's mind towards medical tourism aspect in Malaysia. Thus, Malaysia need to promote various medical success stories together with the services they offer to attract more foreign patients. This study contributes to the theoretical development in the tourism industry by offering the structured relationship among various aspects contributing towards the development of medical tourism in Malaysia.

Medical Tourism in Malaysia: Prospect and Challenges

PubMed Central

2013-01-01

Background: Tourism, combined with the phrase medical, seems to be a new form of tourism which has gained huge popularity in recent decades. Though, a number of literatures available with regard to the tourism industry and the competitiveness of the destination, however, the major aspects which determine the satisfaction of medical tourists are hardly focused specifically on Malaysia. There is a lack of empirical evidence in this area of study which needs to be bridged. Hence, this study aimed at investigating the various factors contributing towards the development of medical tourism in Malaysia. Methods: As the purpose of the research was to find out various factors contributing towards the development of medical tourism in Malaysia, so this study used Structural Equation modeling (SEM) for data analysis. The target population for this study consisted of the medical tourists coming to Malaysia with the primary intension of seeking medical procedures other than sightseeing. A total sample size of 266 was collected through non-probability judgment sampling during the period between December 2012 and February 2013. Results: The result confirms that destination competitiveness and service quality play an important role in the medical tourist’s mind towards medical tourism aspect in Malaysia. Thus, Malaysia need to promote various medical success stories together with the services they offer to attract more foreign patients. Conclusion: This study contributes to the theoretical development in the tourism industry by offering the structured relationship among various aspects contributing towards the development of medical tourism in Malaysia. PMID:26056632

Effects of spatial scale of sampling on food web structure

PubMed Central

Wood, Spencer A; Russell, Roly; Hanson, Dieta; Williams, Richard J; Dunne, Jennifer A

2015-01-01

This study asks whether the spatial scale of sampling alters structural properties of food webs and whether any differences are attributable to changes in species richness and connectance with scale. Understanding how different aspects of sampling effort affect ecological network structure is important for both fundamental ecological knowledge and the application of network analysis in conservation and management. Using a highly resolved food web for the marine intertidal ecosystem of the Sanak Archipelago in the Eastern Aleutian Islands, Alaska, we assess how commonly studied properties of network structure differ for 281 versions of the food web sampled at five levels of spatial scale representing six orders of magnitude in area spread across the archipelago. Species (S) and link (L) richness both increased by approximately one order of magnitude across the five spatial scales. Links per species (L/S) more than doubled, while connectance (C) decreased by approximately two-thirds. Fourteen commonly studied properties of network structure varied systematically with spatial scale of sampling, some increasing and others decreasing. While ecological network properties varied systematically with sampling extent, analyses using the niche model and a power-law scaling relationship indicate that for many properties, this apparent sensitivity is attributable to the increasing S and decreasing C of webs with increasing spatial scale. As long as effects of S and C are accounted for, areal sampling bias does not have a special impact on our understanding of many aspects of network structure. However, attention does need be paid to some properties such as the fraction of species in loops, which increases more than expected with greater spatial scales of sampling. PMID:26380704

Structural impact detection with vibro-haptic interfaces

NASA Astrophysics Data System (ADS)

Jung, Hwee-Kwon; Park, Gyuhae; Todd, Michael D.

2016-07-01

This paper presents a new sensing paradigm for structural impact detection using vibro-haptic interfaces. The goal of this study is to allow humans to ‘feel’ structural responses (impact, shape changes, and damage) and eventually determine health conditions of a structure. The target applications for this study are aerospace structures, in particular, airplane wings. Both hardware and software components are developed to realize the vibro-haptic-based impact detection system. First, L-shape piezoelectric sensor arrays are deployed to measure the acoustic emission data generated by impacts on a wing. Unique haptic signals are then generated by processing the measured acoustic emission data. These haptic signals are wirelessly transmitted to human arms, and with vibro-haptic interface, human pilots could identify impact location, intensity and possibility of subsequent damage initiation. With the haptic interface, the experimental results demonstrate that human could correctly identify such events, while reducing false indications on structural conditions by capitalizing on human’s classification capability. Several important aspects of this study, including development of haptic interfaces, design of optimal human training strategies, and extension of the haptic capability into structural impact detection are summarized in this paper.

Fabrication of high aspect ratio nanopillars and micro/nano combined structures with hydrophobic surface characteristics by injection molding

NASA Astrophysics Data System (ADS)

Zhou, Mingyong; Xiong, Xiang; Jiang, Bingyan; Weng, Can

2018-01-01

Polymer products with micro/nano-structures have excellent mechanical and optical properties, chemical resistance, and other advantages. Injection molding is one of the most potential techniques to fabricate polymer products with micro/nano-structures artificially in large numbers. In this study, a surface approach to fabricate high aspect ratio nanopillars and micro/nano combined structures was presented. Mold insert with micropillar arrays and nanopillars on its surface was prepared by combing anodic aluminum oxide (AAO) template and etched plate. Anti-sticking modification was done on the template to realize a better demolding quality. The influences of mold temperature and polymer material on the final replication quality were investigated. The results showed that the final replication quality of high aspect ratio nanopillars was greatly improved as compared with the unprocessed template. Polymer with low elongation at break was not suitable to fabricate structures with high aspect ratio via injection molding. For polypropylene surface, the experimental results of static contact angles were almost consistent with Cassie-Baxter equation. When the mold temperature reached 178 °C, hair-like polycarbonate nanopillars were observed, resulting in an excellent hydrophobic characteristic.

Method for fabricating high aspect ratio structures in perovskite material

DOEpatents

Karapetrov, Goran T.; Kwok, Wai-Kwong; Crabtree, George W.; Iavarone, Maria

2003-10-28

A method of fabricating high aspect ratio ceramic structures in which a selected portion of perovskite or perovskite-like crystalline material is exposed to a high energy ion beam for a time sufficient to cause the crystalline material contacted by the ion beam to have substantially parallel columnar defects. Then selected portions of the material having substantially parallel columnar defects are etched leaving material with and without substantially parallel columnar defects in a predetermined shape having high aspect ratios of not less than 2 to 1. Etching is accomplished by optical or PMMA lithography. There is also disclosed a structure of a ceramic which is superconducting at a temperature in the range of from about 10.degree. K. to about 90.degree. K. with substantially parallel columnar defects in which the smallest lateral dimension of the structure is less than about 5 microns, and the thickness of the structure is greater than 2 times the smallest lateral dimension of the structure.

Electrohydrodynamic pressure enhanced by free space charge for electrically induced structure formation with high aspect ratio.

PubMed

Tian, Hongmiao; Wang, Chunhui; Shao, Jinyou; Ding, Yucheng; Li, Xiangming

2014-10-28

Electrically induced structure formation (EISF) is an interesting and unique approach for generating a microstructured duplicate from a rheological polymer by a spatially modulated electric field induced by a patterned template. Most of the research on EISF have so far used various dielectric polymers (with an electrical conductivity smaller than 10(-10) S/m that can be considered a perfect dielectric), on which the electric field induces a Maxwell stress only due to the dipoles (or bounded charges) in the polymer molecules, leading to a structure with a small aspect ratio. This paper presents a different approach for improving the aspect ratio allowed in EISF by doping organic salt into the perfect dielectric polymer, i.e., turning the perfect dielectric into a leaky dielectric, considering the fact that the free space charges enriched in the leaky dielectric polymer can make an additional contribution to the Maxwell stress, i.e., electrohydrodynamic pressure, which is desirable for high aspect ratio structuring. Our numerical simulations and experimental tests have shown that a leaky dielectric polymer, with a small conductivity comparable to that of deionized water, can be much more effective at being electrohydrodynamically deformed into a high aspect ratio in comparison with a perfect dielectric polymer when both of them have roughly the same dielectric constant.

The Flow Field Downstream of a Dynamic Low Aspect Ratio Circular Cylinder: A Parametric Study

NASA Astrophysics Data System (ADS)

Gildersleeve, Samantha; Dan, Clingman; Amitay, Michael

2015-11-01

Flow past a static, low aspect ratio cylinder (pin) has shown the formation of vortical structures, namely the horseshoe and arch-type vortex. These vortical structures may have substantial effects in controlling flow separation over airfoils. In the present experiments, the flow field associated with a low aspect ratio cylinder as it interacts with a laminar boundary layer under static and dynamic conditions was investigated through a parametric study over a flat plate. As a result of the pin being actuated in the wall-normal direction, the structures formed in the wake of the pin were seen to be a strong function of actuation amplitude, driving frequency, and aspect ratio of the cylinder. The study was conducted at a Reynolds number of 1875, based on the local boundary layer thickness, with a free stream velocity of 10 m/s. SPIV data were collected for two aspect ratios of 0.75 and 1.125, actuation amplitudes of 6.7% and 16.7%, and driving frequencies of 175 Hz and 350 Hz. Results indicate that the presence and interactions between vortical structures are altered in comparison to the static case and suggest increased large-scale mixing when the pin is driven at the shedding frequency (350 Hz). Supported by the Boeing Company.

Structural Aspects LiNbO3 Nanoparticles and Their Ferromagnetic Properties

PubMed Central

Diaz-Moreno, Carlos A.; Farias-Mancilla, Rurik; Elizalde-Galindo, Jose T.; González-Hernández, Jesus; Hurtado-Macias, Abel; Bahena, Daniel; José-Yacamán, Miguel; Ramos, Manuel

2014-01-01

We present a solid-state synthesis of ferromagnetic lithium niobate nanoparticles (LiNbO3) and their corresponding structural aspects. In order to investigate the effect of heat treatments, two batches of samples with a heat-treated (HT) and non-heat-treated (nHT) reduction at 650 °C in 5% of hydrogen/argon were considered to investigate the multiferroic properties and their corresponding structural aspects; using magnetometry and scanning transmission electron microscopy (STEM). Results indicate the existence of ferromagnetic domains with a magnetic moment per unit cell of 5.24 × 10−3 μB; caused mainly due to voids and defects on the nanoparticle surface, as confirmed by STEM measurements. PMID:28788242

Mechanistic insight into prolonged electromechanical delay in dyssynchronous heart failure: a computational study

PubMed Central

Constantino, Jason; Hu, Yuxuan; Lardo, Albert C.

2013-01-01

In addition to the left bundle branch block type of electrical activation, there are further remodeling aspects associated with dyssynchronous heart failure (HF) that affect the electromechanical behavior of the heart. Among the most important are altered ventricular structure (both geometry and fiber/sheet orientation), abnormal Ca2+ handling, slowed conduction, and reduced wall stiffness. In dyssynchronous HF, the electromechanical delay (EMD), the time interval between local myocyte depolarization and myofiber shortening onset, is prolonged. However, the contributions of the four major HF remodeling aspects in extending EMD in the dyssynchronous failing heart remain unknown. The goal of this study was to determine the individual and combined contributions of HF-induced remodeling aspects to EMD prolongation. We used MRI-based models of dyssynchronous nonfailing and HF canine electromechanics and constructed additional models in which varying combinations of the four remodeling aspects were represented. A left bundle branch block electrical activation sequence was simulated in all models. The simulation results revealed that deranged Ca2+ handling is the primary culprit in extending EMD in dyssynchronous HF, with the other aspects of remodeling contributing insignificantly. Mechanistically, we found that abnormal Ca2+ handling in dyssynchronous HF slows myofiber shortening velocity at the early-activated septum and depresses both myofiber shortening and stretch rate at the late-activated lateral wall. These changes in myofiber dynamics delay the onset of myofiber shortening, thus giving rise to prolonged EMD in dyssynchronous HF. PMID:23934857

Dynamics of market correlations: Taxonomy and portfolio analysis

NASA Astrophysics Data System (ADS)

Onnela, J.-P.; Chakraborti, A.; Kaski, K.; Kertész, J.; Kanto, A.

2003-11-01

The time dependence of the recently introduced minimum spanning tree description of correlations between stocks, called the “asset tree” has been studied in order to reflect the financial market taxonomy. The nodes of the tree are identified with stocks and the distance between them is a unique function of the corresponding element of the correlation matrix. By using the concept of a central vertex, chosen as the most strongly connected node of the tree, an important characteristic is defined by the mean occupation layer. During crashes, due to the strong global correlation in the market, the tree shrinks topologically, and this is shown by a low value of the mean occupation layer. The tree seems to have a scale-free structure where the scaling exponent of the degree distribution is different for “business as usual” and “crash” periods. The basic structure of the tree topology is very robust with respect to time. We also point out that the diversification aspect of portfolio optimization results in the fact that the assets of the classic Markowitz portfolio are always located on the outer leaves of the tree. Technical aspects such as the window size dependence of the investigated quantities are also discussed.

ABC transporters and immunity: mechanism of self-defense.

PubMed

Hinz, Andreas; Tampé, Robert

2012-06-26

The transporter associated with antigen processing (TAP) is a prototype of an asymmetric ATP-binding cassette (ABC) transporter, which uses ATP binding and hydrolysis to translocate peptides from the cytosol to the lumen of the endoplasmic reticulum (ER). Here, we review molecular details of peptide binding and ATP binding and hydrolysis as well as the resulting allosteric cross-talk between the nucleotide-binding domains and the transmembrane domains that drive translocation of the solute across the ER membrane. We also discuss the general molecular architecture of ABC transporters and demonstrate the importance of structural and functional studies for a better understanding of the role of the noncanonical site of asymmetric ABC transporters. Several aspects of peptide binding and specificity illustrate details of peptide translocation by TAP. Furthermore, this ABC transporter forms the central part of the major histocompatibility complex class I (MHC I) peptide-loading machinery. Hence, TAP is confronted with a number of viral factors, which prevent antigen translocation and MHC I loading in virally infected cells. We review how these viral factors have been used as molecular tools to decipher mechanistic aspects of solute translocation and discuss how they can help in the structural analysis of TAP.

Challenges in network science: Applications to infrastructures, climate, social systems and economics

NASA Astrophysics Data System (ADS)

Havlin, S.; Kenett, D. Y.; Ben-Jacob, E.; Bunde, A.; Cohen, R.; Hermann, H.; Kantelhardt, J. W.; Kertész, J.; Kirkpatrick, S.; Kurths, J.; Portugali, J.; Solomon, S.

2012-11-01

Network theory has become one of the most visible theoretical frameworks that can be applied to the description, analysis, understanding, design and repair of multi-level complex systems. Complex networks occur everywhere, in man-made and human social systems, in organic and inorganic matter, from nano to macro scales, and in natural and anthropogenic structures. New applications are developed at an ever-increasing rate and the promise for future growth is high, since increasingly we interact with one another within these vital and complex environments. Despite all the great successes of this field, crucial aspects of multi-level complex systems have been largely ignored. Important challenges of network science are to take into account many of these missing realistic features such as strong coupling between networks (networks are not isolated), the dynamics of networks (networks are not static), interrelationships between structure, dynamics and function of networks, interdependencies in given networks (and other classes of links, including different signs of interactions), and spatial properties (including geographical aspects) of networks. This aim of this paper is to introduce and discuss the challenges that future network science needs to address, and how different disciplines will be accordingly affected.

Understanding the core of RNA interference: The dynamic aspects of Argonaute-mediated processes.

PubMed

Zhu, Lizhe; Jiang, Hanlun; Sheong, Fu Kit; Cui, Xuefeng; Wang, Yanli; Gao, Xin; Huang, Xuhui

2017-09-01

At the core of RNA interference, the Argonaute proteins (Ago) load and utilize small guide nucleic acids to silence mRNAs or cleave foreign nucleic acids in a sequence specific manner. In recent years, based on extensive structural studies of Ago and its interaction with the nucleic acids, considerable progress has been made to reveal the dynamic aspects of various Ago-mediated processes. Here we review these novel insights into the guide-strand loading, duplex unwinding, and effects of seed mismatch, with a focus on two representative Agos, the human Ago 2 (hAgo2) and the bacterial Thermus thermophilus Ago (TtAgo). In particular, comprehensive molecular simulation studies revealed that although sharing similar overall structures, the two Agos have vastly different conformational landscapes and guide-strand loading mechanisms because of the distinct rigidity of their L1-PAZ hinge. Given the central role of the PAZ motions in regulating the exposure of the nucleic acid binding channel, these findings exemplify the importance of protein motions in distinguishing the overlapping, yet distinct, mechanisms of Ago-mediated processes in different organisms. Copyright © 2016 Elsevier Ltd. All rights reserved.

Input-output oriented computation algorithms for the control of large flexible structures

NASA Technical Reports Server (NTRS)

Minto, K. D.

1989-01-01

An overview is given of work in progress aimed at developing computational algorithms addressing two important aspects in the control of large flexible space structures; namely, the selection and placement of sensors and actuators, and the resulting multivariable control law design problem. The issue of sensor/actuator set selection is particularly crucial to obtaining a satisfactory control design, as clearly a poor choice will inherently limit the degree to which good control can be achieved. With regard to control law design, the researchers are driven by concerns stemming from the practical issues associated with eventual implementation of multivariable control laws, such as reliability, limit protection, multimode operation, sampling rate selection, processor throughput, etc. Naturally, the burden imposed by dealing with these aspects of the problem can be reduced by ensuring that the complexity of the compensator is minimized. Our approach to these problems is based on extensions to input/output oriented techniques that have proven useful in the design of multivariable control systems for aircraft engines. In particular, researchers are exploring the use of relative gain analysis and the condition number as a means of quantifying the process of sensor/actuator selection and placement for shape control of a large space platform.

Molecular analysis of NOZZLE, a gene involved in pattern formation and early sporogenesis during sex organ development in Arabidopsis thaliana

PubMed Central

Schiefthaler, Ursula; Balasubramanian, Sureshkumar; Sieber, Patrick; Chevalier, David; Wisman, Ellen; Schneitz, Kay

1999-01-01

Sexual reproduction is a salient aspect of plants, and elaborate structures, such as the flowers of angiosperms, have evolved that aid in this process. Within the flower the corresponding sex organs, the anther and the ovule, form the male and female sporangia, the pollen sac and the nucellus, respectively. However, despite their central role for sexual reproduction little is known about the mechanisms that control the establishment of these important structures. Here we present the identification and molecular characterization of the NOZZLE (NZZ) gene in the flowering plant Arabidopsis thaliana. In several nzz mutants the nucellus and the pollen sac fail to form. It indicates that NZZ plays an early and central role in the development of both types of sporangia and that the mechanisms controlling these processes share a crucial factor. In addition, NZZ may have an early function during male and female sporogenesis as well. The evolutionary aspects of these findings are discussed. NZZ encodes a putative protein of unknown function. However, based on sequence analysis we speculate that NZZ is a nuclear protein and possibly a transcription factor. PMID:10500234

Dynamics of market correlations: taxonomy and portfolio analysis.

PubMed

Onnela, J-P; Chakraborti, A; Kaski, K; Kertész, J; Kanto, A

2003-11-01

The time dependence of the recently introduced minimum spanning tree description of correlations between stocks, called the "asset tree" has been studied in order to reflect the financial market taxonomy. The nodes of the tree are identified with stocks and the distance between them is a unique function of the corresponding element of the correlation matrix. By using the concept of a central vertex, chosen as the most strongly connected node of the tree, an important characteristic is defined by the mean occupation layer. During crashes, due to the strong global correlation in the market, the tree shrinks topologically, and this is shown by a low value of the mean occupation layer. The tree seems to have a scale-free structure where the scaling exponent of the degree distribution is different for "business as usual" and "crash" periods. The basic structure of the tree topology is very robust with respect to time. We also point out that the diversification aspect of portfolio optimization results in the fact that the assets of the classic Markowitz portfolio are always located on the outer leaves of the tree. Technical aspects such as the window size dependence of the investigated quantities are also discussed.

Polish system of education in maritime health care and medical assistance for seafarers.

PubMed

Chodnik, Tomasz; Jeżewska, Maria; Jaremin, Bogdan; Kotłowski, Andrzej; Leszczyńska, Irena; Grubman-Nowak, Marta

2013-01-01

The Polish public awareness of the crucial importance of the own maritime economy to the very existenceof the national state has its historical reasons. The Polish maritime involvement has seen several dramaticcrises, but the Polish nationals have become an established group in the global marine trade workforceand are entitled to the proper health care. In this paper the main maritime health issues are mentioned.To meet the issues, also the national education system provides the opportunities for both seafarers andmedical professionals. The Polish doctors can specialise in the maritime medicine. In many cases the generalmedicine students formations include these topics as well. The psychological aspects are also takeninto account, both of the education of the seafarers and the organisational structure of the Polish healthcare system. Some recent aspects of the Polish participation in the international cooperation in the fieldof the medical support of the maritime economy are also described.

[Multi-ethnic nursing].

PubMed

Gambera, Angelo Antonio; Marucci, Anna Rita; Pezzino, Marcello

2008-01-01

Among the many activities of nurses, the role of intermediary between the client and the health institutions is one of the most important . In this role, nurses may have to deal with cultural conflicts in order to fulfill the requirements of a multi-ethnic client population coming from may different cultures. By adopting an instrument capable of assessing the trans-cultural and inter-cultural knowledge of nurses, it may be possible to fill in any gaps by means of appropriate training or education. The study was performed using an anonymous questionnaire issued to the nurses working in the out-patient structures of the Gynaecological and Maternity Department of the Vittorio Emanuele II Hospital in Catania, which deals with the highest number of non-EEC citizens. The results of the questionnaire indicated that educational intervention to improve knowledge of the principal aspects of transcultural and intercultural nursing , as well as other anthropological and caring aspects was required.

Novel Aspects of Polynucleotide Phosphorylase Function in Streptomyces

PubMed Central

Jones, George H.

2018-01-01

Polynucleotide phosphorylase (PNPase) is a 3′–5′-exoribnuclease that is found in most bacteria and in some eukaryotic organelles. The enzyme plays a key role in RNA decay in these systems. PNPase structure and function have been studied extensively in Escherichia coli, but there are several important aspects of PNPase function in Streptomyces that differ from what is observed in E. coli and other bacterial genera. This review highlights several of those differences: (1) the organization and expression of the PNPase gene in Streptomyces; (2) the possible function of PNPase as an RNA 3′-polyribonucleotide polymerase in Streptomyces; (3) the function of PNPase as both an exoribonuclease and as an RNA 3′-polyribonucleotide polymerase in Streptomyces; (4) the function of (p)ppGpp as a PNPase effector in Streptomyces. The review concludes with a consideration of a number of unanswered questions regarding the function of Streptomyces PNPase, which can be examined experimentally. PMID:29562650

Biophysical Aspects of Alzheimer's Disease: Implications for Pharmaceutical Sciences : Theme: Drug Discovery, Development and Delivery in Alzheimer's Disease Guest Editor: Davide Brambilla.

PubMed

Arosio, Paolo

2017-12-01

An increasing amount of findings suggests that the aggregation of soluble peptides and proteins into amyloid fibrils is a relevant upstream process in the complex cascade of events leading to the pathology of Alzheimer's disease and several other neurodegenerative disorders. Nevertheless, several aspects of the correlation between the aggregation process and the onset and development of the pathology remain largely elusive. In this context, biophysical and biochemical studies in test tubes have proven extremely powerful in providing quantitative information about the structure and the reactivity of amyloids at the molecular level. In this review we use selected recent examples to illustrate the importance of such biophysical research to complement phenomenological studies based on cellular and molecular biology, and we discuss the implications for pharmaceutical applications associated with Alzheimer's disease and other neurodegenerative disorders in both academic and industrial contexts.

Uninterrupted and reusable source for the controlled growth of nanowires

PubMed Central

Sugavaneshwar, R. P.; Nanda, Karuna Kar

2013-01-01

Generally, the length of the oxide nanowires grown by vapor phase transport is limited by the degradation of the source materials. Furthermore, the source material is used once for the nanowires growth. By exploiting the Si-Zn phase diagram, we have developed a simple methodology for the non-catalytic growth of ultralong ZnO nanowires in large area with controllable aspect ratio and branched structures. The insolubility of Zn in Si and the use of a Si cap on the Zn source to prevent local source oxidation of Zn (i. e. prevents the degradation of the source) are the keys to grow longer nanowires without limitations. It has been shown that the aspect ratio can be controlled by thermodynamically (temperature) and more importantly by kinetically (vapor flux). One of the interesting findings is that the same source material can be used for several depositions of oxide nanostructured materials. PMID:23412010

[Organization of clinical research: in general and visceral surgery].

PubMed

Schneider, M; Werner, J; Weitz, J; Büchler, M W

2010-04-01

The structural organization of research facilities within a surgical university center should aim at strengthening the department's research output and likewise provide opportunities for the scientific education of academic surgeons. We suggest a model in which several independent research groups within a surgical department engage in research projects covering various aspects of surgically relevant basic, translational or clinical research. In order to enhance the translational aspects of surgical research, a permanent link needs to be established between the department's scientific research projects and its chief interests in clinical patient care. Importantly, a focus needs to be placed on obtaining evidence-based data to judge the efficacy of novel diagnostic and treatment concepts. Integration of modern technologies from the fields of physics, computer science and molecular medicine into surgical research necessitates cooperation with external research facilities, which can be strengthened by coordinated support programs offered by research funding institutions.

Nucleosomes in the neighborhood

PubMed Central

Dorn, Elizabeth Suzanne

2011-01-01

The importance of local chromatin structure in regulating replication initiation has become increasingly apparent. Most recently, histone methylation and nucleosome positioning have been added to the list of modifications demonstrated to regulate origins. In particular, the methylation states of H3K4, H3K36 and H4K20 have been associated with establishing active, repressed or poised origins depending on the timing and extent of methylation. The stability and precise positioning of nucleosomes has also been demonstrated to affect replication efficiency. Although it is not yet clear how these modifications alter the behavior of specific replication factors, ample evidence establishes their role in maintaining coordinated replication. This review will summarize recent advances in understanding these aspects of chromatin structure in DNA replication origin control. PMID:21364325

P21 activated kinases: structure, regulation, and functions.

PubMed

Rane, Chetan K; Minden, Audrey

2014-01-01

The p21 activated kinases (Paks) are well known effector proteins for the Rho GTPases Cdc42 and Rac. The Paks contain 6 members, which fall into 2 families of proteins. The first family consists of Paks 1, 2, and 3, and the second consists of Paks 4, 5, and 6. While some of the Paks are ubiquitously expressed, others have more restrictive tissue specificity. All of them are found in the nervous system. Studies using cell culture, transgenic mice, and knockout mice, have revealed important roles for the Paks in cytoskeletal organization and in many aspects of cell growth and development. This review discusses the basic structures of the Paks, and their roles in cell growth, development, and in cancer.

Production, properties, and industrial food application of lactic acid bacteria-derived exopolysaccharides.

PubMed

Zannini, Emanuele; Waters, Deborah M; Coffey, Aidan; Arendt, Elke K

2016-02-01

Exopolysaccharides (EPS)-producing lactic acid bacteria (LAB) are industrially important microorganisms in the development of functional food products and are used as starter cultures or coadjutants to develop fermented foods. There is large variability in EPS production by LAB in terms of chemical composition, quantity, molecular size, charge, presence of side chains, and rigidity of the molecules. The main body of the review will cover practical aspects concerning the structural diversity structure of EPS, and their concrete application in food industries is reported in details. To strengthen the food application and process feasibility of LAB EPS at industrial level, a future academic research should be combined with industrial input to understand the technical shortfalls that EPS can address.

Visualizing Sweetness: Increasingly Diverse Applications for Fluorescent-Tagged Glucose Bioprobes and Their Recent Structural Modifications

PubMed Central

Kim, Woong Hee; Lee, Jinho; Jung, Da-Woon; Williams, Darren R.

2012-01-01

Glucose homeostasis is a fundamental aspect of life and its dysregulation is associated with important diseases, such as cancer and diabetes. Traditionally, glucose radioisotopes have been used to monitor glucose utilization in biological systems. Fluorescent-tagged glucose analogues were initially developed in the 1980s, but it is only in the past decade that their use as a glucose sensor has increased significantly. These analogues were developed for monitoring glucose uptake in blood cells, but their recent applications include tracking glucose uptake by tumor cells and imaging brain cell metabolism. This review outlines the development of fluorescent-tagged glucose analogues, describes their recent structural modifications and discusses their increasingly diverse biological applications. PMID:22666073

Hooked on α-d-galactosidases: from biomedicine to enzymatic synthesis.

PubMed

Bakunina, Irina Yu; Balabanova, Larissa A; Pennacchio, Angela; Trincone, Antonio

2016-01-01

α-d-Galactosidases (EC 3.2.1.22) are enzymes employed in a number of useful bio-based applications. We have depicted a comprehensive general survey of α-d-galactosidases from different origin with special emphasis on marine example(s). The structures of natural α-galactosyl containing compounds are described. In addition to 3D structures and mechanisms of action of α-d-galactosidases, different sources, natural function and genetic regulation are also covered. Finally, hydrolytic and synthetic exploitations as free or immobilized biocatalysts are reviewed. Interest in the synthetic aspects during the next years is anticipated for access to important small molecules by green technology with an emphasis on alternative selectivity of this class of enzymes from different sources.

Informational technologies in modern educational structure

NASA Astrophysics Data System (ADS)

Fedyanin, A. B.

2017-01-01

The article represents the structure of informational technologies complex that is applied in modern school education, describes the most important educational methods, shows the results of their implementation. It represents the forms and methods of educational process informative support usage, examined in respects of different aspects of their using that take into account also the psychological features of students. A range of anxious facts and dangerous trends connected with the usage and distribution of the informational technologies that are to be taken into account in the educational process of informatization is also indicated in the article. Materials of the article are based on the experience of many years in operation and development of the informational educational sphere on the basis of secondary school of the physics and mathematics specialization.

A study of elementary teachers' conceptions of nature of science and their beliefs about the developmental appropriateness and importance of nature of science throughout a professional development program

NASA Astrophysics Data System (ADS)

Adibelli, Elif

This qualitative study aimed to explore the changes in elementary science teachers' conceptions of nature of science (NOS) and their beliefs about the developmental appropriateness and importance of NOS after participating in an academic, year-long professional development program (PDP) as well as the factors facilitating these changes. The PDP consisted of two phases. In the first phase, the participants received NOS training designed with an explicit-reflective instructional approach. In the second phase, the participants implemented several NOS training activities in their classrooms. Four elementary science teachers who volunteered and completed all components of the PDP (i.e., the NOS training and the NOS teaching) comprised the participants of the present study. A multiple-embedded case study design was employed to explore the changes in the elementary science teachers' conceptions of NOS and their beliefs about the developmental appropriateness and importance of NOS. The study data were collected from multiple sources. The primary data sources included (a) Views of Nature of Science Elementary School Version 2 (VNOS-D2) questionnaire (Lederman & Khishfe, 2002), (b) Ideas about Science for Early Elementary (K-4) Students questionnaire (Sweeney, 2010), and (c) follow-up semi-structured interviews. The secondary data sources included videotaping of meetings with teachers, reflective field notes, and artifacts produced by teachers and their students. Data were analyzed using Yin's (1994, 2003) analytic tactics of pattern matching, explanation building, and cross-case synthesis. The findings of the study revealed that the elementary science teachers showed gradual, but substantial changes in their conceptions, and beliefs about the developmental appropriateness and importance of the NOS aspects over the course of participation in the PDP. Moreover, the participants identified nine components in the PDP that facilitated these changes in their conceptions, and beliefs about the developmental appropriateness and importance of the NOS aspects. These components were (a) specific focus on the NOS content, (b) participation in hands-on activities on NOS, (c) educational readings on NOS, (d) multiple types/ formats of reflection, (e) multiple exposure to the NOS content, (f) structural consistency in the presentation of the NOS content, (g) the evaluation of secondary student data, (h) the analysis of national and state science standards in terms of NOS, and (i) the implementation of the NOS activities in the classroom. Based on the findings of this study, it may be concluded that explicit-reflective NOS instruction coupled with NOS teaching is sufficient to evolve and crystallize teachers' conceptions and beliefs about the developmental appropriateness and importance of the NOS aspects.

Investigating Conceptual, Procedural, and Intuitive Aspects of Area Measurement with Non-Square Area Units

ERIC Educational Resources Information Center

Miller, Amanda L.

2013-01-01

This dissertation reports the results of a qualitative research project on area measurement. The study utilized structured, task-based interviews with students to (a) investigate the ways students enumerate and structure two-dimensional space with a variety of area units; (b) identify conceptual, procedural, and intuitive aspects of area…

Structural and Dynamic Aspects of Interest Development: Theoretical Considerations from an Ontogenetic Perspective.

ERIC Educational Resources Information Center

Krapp, Andreas

2002-01-01

Presents a collection of theoretical concepts and models that can be used to describe and explore structural and dynamic aspects of interest development from an ontogenic research perspective. Outlines basic ideas of an educational-psychological conceptualization of interest that is based on a dynamic theory of personality. (SLD)

[Anterior dislocation of the popliteus tendon].

PubMed

Martinez Molina, Oscar

2009-01-01

Review the most relevant aspects of the posterolateral corner anatomy of the knee, based on the analysis of papers that throughout the years have made important contributions to the knowledge of these structures. Last et al rejected the idea that the popliteal tendon is an isolated structure, suggesting rather that its variants are closely linked to other anatomical structures. The studies by Tria et al contributed the features of the tendon as it attaches to the lateral condyle, just to mention a couple of examples. This is the case of a 48 year-old female patient with a knee injury caused by an external rotation mechanism. Clinical features included pain, a protruding sensation in the lateral aspect of the knee, and voluntary pseudoblocking resulting from external rotation maneuvers. Knee arthroscopy was performed and dislocation of the popliteal tendon anterior to the lateral condyle was diagnosed, besides a longitudinal tear. The tendon was repositioned, radiofrequency was applied to both the tendon and the popliteal hiatus, and the former was kept in place with a plaster cast worn for 6 weeks. Even though the isolated tear or avulsion of the tendon has already been reported, the dislocation or instability of the popliteal tendon as it relates to the lateral femoral condyle has apparently not been approached yet. As we did in this case, other authors have also confirmed the diagnosis arthroscopically, Naver in 1985, Rose in 1988, and Burstein in 1990.

The Construction of Impossibility: A Logic-Based Analysis of Conjuring Tricks

PubMed Central

Smith, Wally; Dignum, Frank; Sonenberg, Liz

2016-01-01

Psychologists and cognitive scientists have long drawn insights and evidence from stage magic about human perceptual and attentional errors. We present a complementary analysis of conjuring tricks that seeks to understand the experience of impossibility that they produce. Our account is first motivated by insights about the constructional aspects of conjuring drawn from magicians' instructional texts. A view is then presented of the logical nature of impossibility as an unresolvable contradiction between a perception-supported belief about a situation and a memory-supported expectation. We argue that this condition of impossibility is constructed not simply through misperceptions and misattentions, but rather it is an outcome of a trick's whole structure of events. This structure is conceptualized as two parallel event sequences: an effect sequence that the spectator is intended to believe; and a method sequence that the magician understands as happening. We illustrate the value of this approach through an analysis of a simple close-up trick, Martin Gardner's Turnabout. A formalism called propositional dynamic logic is used to describe some of its logical aspects. This elucidates the nature and importance of the relationship between a trick's effect sequence and its method sequence, characterized by the careful arrangement of four evidence relationships: similarity, perceptual equivalence, structural equivalence, and congruence. The analysis further identifies two characteristics of magical apparatus that enable the construction of apparent impossibility: substitutable elements and stable occlusion. PMID:27378959

Crisis management systems: staff nurses demand more support from their supervisors.

PubMed

Tzeng, Huey-Ming; Yin, Chang-Yi

2008-08-01

This study illustrates the contributions of the necessity, comprehensiveness, and difference (between necessity and comprehensiveness) levels of crisis management systems to participants' general satisfaction with their working institutions' nursing-related crisis management activities. Crisis management systems include strategic, technical/structural, assessment, public communication, and psychological/cultural aspects. An effective institutional crisis management system might help to decrease the number of incidents related to medical disputes or to prevent a crisis from worsening and becoming disastrous. A cross-sectional survey was administered during a nursing conference held in Taipei, Taiwan, on June 27, 2005. Two hundred ninety questionnaires were distributed, and 121 were retrieved (response rate, 41.7%; nursing administrators and staff). Univariate and multivariate analyses were performed. Ordinal logistic regression analyses show that being a public hospital managed by the government and having more difference on the strategic aspect between the necessity and comprehensiveness levels contribute to lower satisfaction with nursing-related crisis management activities (Nagelkerke R(2) = .441). In addition, staff nurses perceive higher necessity levels on all five aspects compared to nursing administrators. This study provides important insights into how the policies and activities of a medical institution's crisis management system can be prioritized and implemented. It is also important for students in nursing programs and for currently employed nurses to learn how to manage disputes related to nursing practice, so that early resolution can be achieved and crises can be avoided. These results suggest that staff nurses demand more support from their supervisors.

The uses and implications of standards in general practice consultations.

PubMed

Lippert, Maria Laura; Reventlow, Susanne; Kousgaard, Marius Brostrøm

2017-01-01

Quality standards play an increasingly important role in primary care through their inscription in various technologies for improving professional practice. While 'hard' biomedical standards have been the most common and debated, current quality development initiatives increasingly seek to include standards for the 'softer' aspects of care. This article explores the consequences of both kinds of quality standards for chronic care consultations. The article presents findings from an explorative qualitative field study in Danish general practice where a standardized technology for quality development has been introduced. Data from semi-structured interviews and observations among 17 general practitioners were analysed using an iterative analytical approach, which served to identify important variations in the uses and impacts of the technology. The most pronounced impact of the technology was observed among general practitioners who strictly adhered to the procedural standards on the interactional aspects of care. Thus, when allowed to function as an overall frame for consultations, those standards supported adherence to general recommendations regarding which elements to be included in chronic disease consultations. However, at the same time, adherence to those standards was observed to narrow the focus of doctor-patient dialogues and to divert general practitioners' attention from patients' personal concerns. Similar consequences of quality standards have previously been framed as manifestations of an inherent conflict between principles of patient-centredness and formal biomedical quality standards. However, this study suggests that standards on the 'softer' aspects of care may just as well interfere with a clinical approach relying on situated and attentive interactions with patients.

Environmental and Energy Aspects of Construction Industry and Green Buildings

NASA Astrophysics Data System (ADS)

Kauskale, L.; Geipele, I.; Zeltins, N.; Lecis, I.

2017-04-01

Green building is an important component of sustainable real estate market development, and one of the reasons is that the construction industry consumes a high amount of resources. Energy consumption of construction industry results in greenhouse gas emissions, so green buildings, energy systems, building technologies and other aspects play an important role in sustainable development of real estate market, construction and environmental development. The aim of the research is to analyse environmental aspects of sustainable real estate market development, focusing on importance of green buildings at the industry level and related energy aspects. Literature review, historical, statistical data analysis and logical access methods have been used in the research. The conducted research resulted in high environmental rationale and importance of environment-friendly buildings, and there are many green building benefits during the building life cycle. Future research direction is environmental information process and its models.

Assessment of Surgical Skills and Competency.

PubMed

Bhatti, Nasir I

2017-10-01

Evaluation of surgical skills and competency are important aspects of the medical education process. Measurable and reproducible methods of assessment with objective feedback are essential components of surgical training. Objective Structured Assessment of Technical Skills (OSATS) is widely used across the medical specialties and otolaryngology-specific tools have been developed and validated for sinus and mastoid surgery. Although assessment of surgical skills can be time-consuming and requires human and financial resources, new evaluation methods and emerging technology may alleviate these barriers while also improving data collection practices. Copyright © 2017 Elsevier Inc. All rights reserved.

Ontological analysis of SNOMED CT.

PubMed

Héja, Gergely; Surján, György; Varga, Péter

2008-10-27

SNOMED CT is the most comprehensive medical terminology. However, its use for intelligent services based on formal reasoning is questionable. The analysis of the structure of SNOMED CT is based on the formal top-level ontology DOLCE. The analysis revealed several ontological and knowledge-engineering errors, the most important are errors in the hierarchy (mostly from an ontological point of view, but also regarding medical aspects) and the mixing of subsumption relations with other types (mostly 'part of'). The found errors impede formal reasoning. The paper presents a possible way to correct these problems.

Effective radiology dashboards: key research findings.

PubMed

Karami, Mahtab; Safdari, Reza; Rahimi, Azin

2013-01-01

Innovative organizations have access to information for business intelligence through the objectives displayed in dashboards. In healthcare organizations, where the goal is to improve quality of care along with reducing costs, the radiology department is important from both financial and clinical aspects. Therefore, how to manage this department has critical impact on the effectiveness and efficiency of the organization. Today, since the information in this department not only has different data structure but also is gathered from different data sources, a well defined, comprehensive dashboard can be an effective tool to enhance performance.

Facetten der Reurbanisierung. Das Beispiel Mönchengladbach

NASA Astrophysics Data System (ADS)

Hamm, Rüdiger; Jäger, Angelika; Keggenhoff, Katja

2017-06-01

In the light of an increasing importance of the discussion on reurbanization, the article analyses the current socioeconomical and structural development of the city of Moenchengladbach. City development processes are marked by a high degree of dynamic individualization - an increasing number of cities have achieved a stage of reurbanization, whereas others have not completeley reached that stage of urban renewal. An analysis of Moenchengladbach indicates that quantative aspects of reurbanization are fulfilled, whereas qualitative reurbanisation processes as an increasing attractiveness, urban revaluation, and gentrification of innercity areas remain a future potential.

A new architecture as transparent electrodes for solar and IR applications based on photonic structures via soft lithography

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

Kuang, Ping

2011-01-01

Transparent conducting electrodes with the combination of high optical transmission and good electrical conductivity are essential for solar energy harvesting and electric lighting devices. Currently, indium tin oxide (ITO) is used because ITO offers relatively high transparency (>80%) to visible light and low sheet resistance (R s = 10 ohms/square (Ω /2)) for electrical conduction. However, ITO is costly due to limited indium reserves, and it is brittle. These disadvantages have motivated the search for other conducting electrodes with similar or better properties. There has been research on a variety of electrode structures involving carbon nanotube networks, graphene films, nanowiremore » and nanopatterned meshes and grids. Due to their novel characteristics in light manipulation and collection, photonic crystal structures show promise for further improvement. Here, we report on a new architecture consisting of nanoscale high aspect ratio metallic photonic structures as transparent electrodes fabricated via a combination of processes. For (Au) and silver (Ag) structures, the visible light transmission can reach as high as 80%, and the sheet resistance of the structure can be as low as 3.2Ω /2. The optical transparency of the high aspect ratio metal structures at visible wavelength range is comparable to that of ITO glass, while their sheet resistance is more than 3 times lower, which indicates a much higher electrical conductivity of the metal structures. Furthermore, the high aspect ratio metal structures have very high infrared (IR) reflection (90%) for the transverse magnetic (TM) mode, which can lead to the development of fabrication of metallic structures as IR filters for heat control applications. Investigations of interdigitated structures based on the high aspect ratio metal electrodes are ongoing to study the feasibility in smart window applications in light transmission modulation.« less

Biomolecular electrostatics and solvation: a computational perspective

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

Ren, Pengyu; Chun, Jaehun; Thomas, Dennis G.

2012-11-01

An understanding of molecular interactions is essential for insight into biological systems at the molecular scale. Among the various components of molecular interactions, electrostatics are of special importance because of their long-range nature and their influence on polar or charged molecules, including water, aqueous ions, proteins, nucleic acids, carbohydrates, and membrane lipids. In particular, robust models of electrostatic interactions are essential for understanding the solvation properties of biomolecules and the effects of solvation upon biomolecular folding, binding, enzyme catalysis and dynamics. Electrostatics, therefore, are of central importance to understanding biomolecular structure and modeling interactions within and among biological molecules. Thismore » review discusses the solvation of biomolecules with a computational biophysics view towards describing the phenomenon. While our main focus lies on the computational aspect of the models, we summarize the common characteristics of biomolecular solvation (e.g., solvent structure, polarization, ion binding, and nonpolar behavior) in order to provide reasonable backgrounds to understand the solvation models.« less

Characteristics of the postcounseling reproductive decision-making process: an explorative study.

PubMed

Frets, P G; Verhage, F; Niermeijer, M F

1991-09-01

An in-depth, recorded interview of 30 couples 2-3 years after genetic counseling explored the characteristics of the postcounseling decision-making process, including the role of guilt feelings towards the proband. The study concerned couples with an affected child, sib, or spouse. Results were evaluated by 2 to 4 judges. In contrast to other studies, a generally unstructured decision-making process was found whereby guilt feelings played a significant role in more than half the couples. Guilt feelings were more predominant in couples with an affected sib than in those with an affected spouse. Lack of structure did not seem to complicate the decision-making process. Therefore, authors do not advocate promotion of structuring the decision-making process. Genetic counselors might focus on understanding counselees' feelings concerning the reproductive decision. Acceptance of apparently irrational considerations is particularly important, because these feelings indicate the influence of unconscious motives. Another important aspect of supporting counselees is to understand the role played by guilt feelings toward parents or an affected sib.

Biomolecular electrostatics and solvation: a computational perspective

PubMed Central

Ren, Pengyu; Chun, Jaehun; Thomas, Dennis G.; Schnieders, Michael J.; Marucho, Marcelo; Zhang, Jiajing; Baker, Nathan A.

2012-01-01

An understanding of molecular interactions is essential for insight into biological systems at the molecular scale. Among the various components of molecular interactions, electrostatics are of special importance because of their long-range nature and their influence on polar or charged molecules, including water, aqueous ions, proteins, nucleic acids, carbohydrates, and membrane lipids. In particular, robust models of electrostatic interactions are essential for understanding the solvation properties of biomolecules and the effects of solvation upon biomolecular folding, binding, enzyme catalysis, and dynamics. Electrostatics, therefore, are of central importance to understanding biomolecular structure and modeling interactions within and among biological molecules. This review discusses the solvation of biomolecules with a computational biophysics view towards describing the phenomenon. While our main focus lies on the computational aspect of the models, we provide an overview of the basic elements of biomolecular solvation (e.g., solvent structure, polarization, ion binding, and nonpolar behavior) in order to provide a background to understand the different types of solvation models. PMID:23217364

Biomolecular electrostatics and solvation: a computational perspective.

PubMed

Ren, Pengyu; Chun, Jaehun; Thomas, Dennis G; Schnieders, Michael J; Marucho, Marcelo; Zhang, Jiajing; Baker, Nathan A

2012-11-01

An understanding of molecular interactions is essential for insight into biological systems at the molecular scale. Among the various components of molecular interactions, electrostatics are of special importance because of their long-range nature and their influence on polar or charged molecules, including water, aqueous ions, proteins, nucleic acids, carbohydrates, and membrane lipids. In particular, robust models of electrostatic interactions are essential for understanding the solvation properties of biomolecules and the effects of solvation upon biomolecular folding, binding, enzyme catalysis, and dynamics. Electrostatics, therefore, are of central importance to understanding biomolecular structure and modeling interactions within and among biological molecules. This review discusses the solvation of biomolecules with a computational biophysics view toward describing the phenomenon. While our main focus lies on the computational aspect of the models, we provide an overview of the basic elements of biomolecular solvation (e.g. solvent structure, polarization, ion binding, and non-polar behavior) in order to provide a background to understand the different types of solvation models.

Copy Number Variations Detection: Unravelling the Problem in Tangible Aspects.

PubMed

do Nascimento, Francisco; Guimaraes, Katia S

2017-01-01

In the midst of the important genomic variants associated to the susceptibility and resistance to complex diseases, Copy Number Variations (CNV) has emerged as a prevalent class of structural variation. Following the flood of next-generation sequencing data, numerous tools publicly available have been developed to provide computational strategies to identify CNV at improved accuracy. This review goes beyond scrutinizing the main approaches widely used for structural variants detection in general, including Split-Read, Paired-End Mapping, Read-Depth, and Assembly-based. In this paper, (1) we characterize the relevant technical details around the detection of CNV, which can affect the estimation of breakpoints and number of copies, (2) we pinpoint the most important insights related to GC-content and mappability biases, and (3) we discuss the paramount caveats in the tools evaluation process. The points brought out in this study emphasize common assumptions, a variety of possible limitations, valuable insights, and directions for desirable contributions to the state-of-the-art in CNV detection tools.

New type IIB backgrounds and aspects of their field theory duals

NASA Astrophysics Data System (ADS)

Caceres, Elena; Macpherson, Niall T.; Núñez, Carlos

2014-08-01

In this paper we study aspects of geometries in Type IIA and Type IIB String theory and elaborate on their field theory dual pairs. The backgrounds are associated with reductions to Type IIA of solutions with G 2 holonomy in eleven dimensions. We classify these backgrounds according to their G-structure, perform a non-Abelian T-duality on them and find new Type IIB configurations presenting dynamical SU(2)-structure. We study some aspects of the associated field theories defined by these new backgrounds. Various technical details are clearly spelled out.

Petroleum production structures: economic resources for Louisiana sport divers

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

Roberts, K.J.; Thompson, M.E.

1983-08-01

The era of expanding petroleum production from marine waters began 12 miles off the Louisiana coast in 1947 with a joint operation. Since then, the expansion of drilling and production operations has continued until, in 1981, approximately 3,500 structures were located in the Gulf of Mexico. Of the total number of structures, federal and state waters off Louisiana contain 3,100. Scientific articles dealing with the role of structures in marine habitat and their relationship to sport fishing in the Gulf of Mexico increased over the decade. This newly publicized beneficial aspect of structures is particularly important to the marine fisherymore » off Louisiana. The structures (to which Dugas et al. attribute 'nearly all of the offshore sport fishery') are called as platforms in their description: These platforms are supported by a prewelded framework of steel pipe. Structures in other areas of the country also attract marine life and sport fishermen. Catch rates by sport fishermen were two to three times higher near structures off California than near natural reefs. (Turner et al. 1969). This may be the result of the 'fish-concentrating' nature of structures.« less

[Advances in studies on the structure of farmland shelterbelt ecosystem].

PubMed

Li, Chunping; Guan, Wenbin; Fan, Zhiping; Su, Fanxin; Wang, Xilin

2003-11-01

The ecological function of farmland shelterbelt system is determined by its structure. The spatio-temporal structure is a key aspect in related researches, which is very necessary to study the integrity, stability and durability of shelterbelt modules. In this article, the researches on the structure of farmland shelterbelt ecosystem were reviewed from the four scales of tree structure, shelterbelt structure, shelterbelts network and landscape structure. The principles, methods and productions of each scale were summarized, and the prospects were also discussed. Dynamic simulation of tree growth process in shelterbelts could be conducted by the theory of form and quality structure of tree and by fractal graphics, which were helpful to study the mechanism of individual trees and belts based on photosynthetic and transpiration mechanism of individual trees. The mechanism model of shelterbelt porosity should be conducted, so that, the sustainable yield model of shelterbelt management could be established, and the optimized model of shelterbelt networks with multi-special and multi-hierarchical structure could also be formed. Evaluating the reasonability, stability and durability of shelterbelt landscape based on the theories and methods of landscape ecology was an important task in the future studies.

Abnormal semantic knowledge in a case of developmental amnesia.

PubMed

Blumenthal, Anna; Duke, Devin; Bowles, Ben; Gilboa, Asaf; Rosenbaum, R Shayna; Köhler, Stefan; McRae, Ken

2017-07-28

An important theory holds that semantic knowledge can develop independently of episodic memory. One strong source of evidence supporting this independence comes from the observation that individuals with early hippocampal damage leading to developmental amnesia generally perform normally on standard tests of semantic memory, despite their profound impairment in episodic memory. However, one aspect of semantic memory that has not been explored is conceptual structure. We built on the theoretically important distinction between intrinsic features of object concepts (e.g., shape, colour, parts) and extrinsic features (e.g., how something is used, where it is typically located). The accrual of extrinsic feature knowledge that is important for concepts such as chair or spoon may depend on binding mechanisms in the hippocampus. We tested HC, an individual with developmental amnesia due to a well-characterized lesion of the hippocampus, on her ability to generate semantic features for object concepts. HC generated fewer extrinsic features than controls, but a similar number of intrinsic features than controls. We also tested her on typicality ratings. Her typicality ratings were abnormal for nonliving things (which more strongly depend on extrinsic features), but normal for living things (which more strongly depend on intrinsic features). In contrast, NB, who has MTL but not hippocampal damage due to surgery, showed no impairments in either task. These results suggest that episodic and semantic memory are not entirely independent, and that the hippocampus is important for learning some aspects of conceptual knowledge. Copyright © 2017 Elsevier Ltd. All rights reserved.

Knowledge-based model building of proteins: concepts and examples.

PubMed Central

Bajorath, J.; Stenkamp, R.; Aruffo, A.

1993-01-01

We describe how to build protein models from structural templates. Methods to identify structural similarities between proteins in cases of significant, moderate to low, or virtually absent sequence similarity are discussed. The detection and evaluation of structural relationships is emphasized as a central aspect of protein modeling, distinct from the more technical aspects of model building. Computational techniques to generate and complement comparative protein models are also reviewed. Two examples, P-selectin and gp39, are presented to illustrate the derivation of protein model structures and their use in experimental studies. PMID:7505680

Modelling indirect interactions during failure spreading in a project activity network.

PubMed

Ellinas, Christos

2018-03-12

Spreading broadly refers to the notion of an entity propagating throughout a networked system via its interacting components. Evidence of its ubiquity and severity can be seen in a range of phenomena, from disease epidemics to financial systemic risk. In order to understand the dynamics of these critical phenomena, computational models map the probability of propagation as a function of direct exposure, typically in the form of pairwise interactions between components. By doing so, the important role of indirect interactions remains unexplored. In response, we develop a simple model that accounts for the effect of both direct and subsequent exposure, which we deploy in the novel context of failure propagation within a real-world engineering project. We show that subsequent exposure has a significant effect in key aspects, including the: (a) final spreading event size, (b) propagation rate, and (c) spreading event structure. In addition, we demonstrate the existence of 'hidden influentials' in large-scale spreading events, and evaluate the role of direct and subsequent exposure in their emergence. Given the evidence of the importance of subsequent exposure, our findings offer new insight on particular aspects that need to be included when modelling network dynamics in general, and spreading processes specifically.

Improving the professional support for parents of young infants.

PubMed

Eronen, Ritva; Calabretto, Helen; Pincombe, Jan

2011-01-01

The objective of this study was to discuss ideas for improving child health services on the basis of findings of an observational study that was designed to explore the role of child health nurses in supporting parents during the first 6 months following the birth of an infant. As part of a larger study in a child health service in urban Australia, surveys were used to collect data from two independent samples of both parents and nurses at an 8-month interval. Data were condensed using factor analysis; regression analyses were used to determine which aspects of care were most important for the parents, and importance-performance analysis was used to determine which aspects of care needed improvement. While the majority of parents valued support from child health nurses, a need for improvement was identified in empowering parents to make their own decisions, discussing emotional issues with parents, providing continuity of care and giving consistent advice. Organisations should value and provide support for child health nurses in their invisible, non-quantifiable work of supporting families. The structure of child health services should also provide child health nurses continuity of care with the families they support.

Learning, assessment and professional identity development in public health training.

PubMed

Wood, Annette

2016-06-01

Professional identity formation is important for new recruits to training programmes. The integration of the accumulation of knowledge and assessment is a key aspect in its acquisition. This study assessed this interaction in Public Health Training in one English region. Semi-structured interviews were held with 15 registrars from the West Midlands Public Health Training Programme. Pre-interview questionnaires gathered background information. A thematic content analysis approach was taken. There was a lack of integration between academic and workplace learning, the professional examination process and professional identity development. Registrars considered sitting the examination and their workplace learning as two parallel processes. Passing the examination was considered a key part in the early development of a professional identity but this was replaced by the opinions of others by the third year of training. Having a Masters' in Public Health was less important but played a different role in their perceived acceptance by the wider Public Health workforce. The lack of integration between assessment and learning seemed to have a detrimental effect on professional identity development. A review of how these two aspects might combine in a more positive manner is needed.

De-adhesion dynamics of melanoma cells from brain endothelial layer.

PubMed

Varga, Béla; Domokos, Réka Anita; Fazakas, Csilla; Wilhelm, Imola; Krizbai, István A; Szegletes, Zsolt; Gergely, Csilla; Váró, György; Végh, Attila G

2018-03-01

Metastasis formation is a complex and not entirely understood process. The poorest prognosis and the most feared complications are associated to brain metastases. Melanoma derived brain metastases show the highest prevalence. Due to the lack of classical lymphatic drainage, in the process of brain metastases formation the haematogenous route is of primordial importance. The first and crucial step in this multistep process is the establishment of firm adhesion between the blood travelling melanoma cells and the tightly connected layer of the endothelium, which is the fundamental structure of the blood-brain barrier. This study compares the de-adhesion properties and dynamics of three melanoma cells types (WM35, A2058 and A375) to a confluent layer of brain micro-capillary endothelial cells. Cell type dependent adhesion characteristics are presented, pointing towards the existence of metastatic potential related nanomechanical aspects. Apparent mechanical properties such as elasticity, maximal adhesion force, number, size and distance of individual rupture events showed altered values pointing towards cell type dependent aspects. Our results underline the importance of mechanical details in case of intercellular interactions. Nevertheless, it suggests that in adequate circumstances elastic and adhesive characterizations might be used as biomarkers. Copyright © 2017. Published by Elsevier B.V.

Alignment between chain quality management and chain governance in EU pork supply chains: a Transaction-Cost-Economics perspective.

PubMed

Wever, Mark; Wognum, Nel; Trienekens, Jacques; Omta, Onno

2010-02-01

Although inter-firm coordination of quality management is increasingly important for meeting end-customer demand in agri-food chains, few researchers focus on the relation between inter-firm quality management systems (QMS) and inter-firm governance structures (GS). However, failure to align QMSs and GSs may lead to inefficiencies in quality management because of high transaction-costs. In addition, misalignment is likely to reduce the quality of end-customer products. This paper addresses this gap in research by empirically examining the relation between QMSs and GSs in pork meat supply chains. Transaction-Cost-Economic theory is used to develop propositions about the relation between three aspects of QMSs--ownership, vertical scope and scale of adoption--and the use of different types of GSs in pork meat supply chains. To validate the propositions, seven cases are examined from four different countries. The results show that the different aspects of QMSs largely relate to specific GSs used in chains in the manner predicted by the propositions. This supports the view that alignment between QMSs and GSs is important for the efficient coordination of quality management in (pork meat) supply chains.

Relative suppression of magical thinking: a transcranial magnetic stimulation study.

PubMed

Bell, Vaughan; Reddy, Venu; Halligan, Peter; Kirov, George; Ellis, Hadyn

2007-05-01

The tendency to perceive meaning in noise (apophenia) has been linked to "magical thinking" (MT), a distinctive form of thinking associated with a range of normal cognitive styles, anomalous perceptual experiences and frank psychosis. Important aspects of MT include the propensity to imbue meaning or causality to events that might otherwise be considered coincidental. Structures in the lateral temporal lobes have been hypothesised to be involved in both the clinical and nonclinical aspects of MT. Accordingly, in this study we used single-pulse transcranial magnetic stimulation (TMS) to stimulate either the left or right lateral temporal areas, or the vertex, of 12 healthy participants (balanced for similar levels of MT, delusional ideation and temporal lobe disturbance) while they were required to indicate if they had "detected" pictures, claimed to be present by the experimenters, in visual noise. Relative to the vertex, TMS inhibition of the left lateral temporal area produced significant reduced tendency to report meaningful information, suggesting that left lateral temporal activation may be more important in MT and therefore producing and supporting anomalous beliefs and experiences. The effect cannot simply be explained by TMS induced cognitive slowing as reaction times were not affected.

Phosphoinositide kinases and the synthesis of polyphosphoinositides in higher plant cells

NASA Technical Reports Server (NTRS)

Drobak, B. K.; Dewey, R. E.; Boss, W. F.; Davies, E. (Principal Investigator)

1999-01-01

Phosphoinositides are a family of inositol-containing phospholipids which are present in all eukaryotic cells. Although in most cells these lipids, with the exception of phosphatidylinositol, constitute only a very minor proportion of total cellular lipids, they have received immense attention by researchers in the past 15-20 years. This is due to the discovery that these lipids, rather than just having structural functions, play key roles in a wide range of important cellular processes. Much less is known about the plant phosphoinositides than about their mammalian counterparts. However, it has been established that a functional phosphoinositide system exists in plant cells and it is becoming increasingly clear that inositol-containing lipids are likely to play many important roles throughout the life of a plant. It is not our intention to give an exhaustive overview of all aspects of the field, but rather we focus on the phosphoinositide kinases responsible for the synthesis of all phosphorylated forms of phosphatidylinositol. Also, we mention some of the aspects of current phosphoinositide research which, in our opinion, are most likely to provide a suitable starting point for further research into the role of phosphoinositides in plants.

Unusual strategies for using indium gallium nitride grown on silicon (111) for solid-state lighting

PubMed Central

Kim, Hoon-sik; Brueckner, Eric; Song, Jizhou; Li, Yuhang; Kim, Seok; Lu, Chaofeng; Sulkin, Joshua; Choquette, Kent; Huang, Yonggang; Nuzzo, Ralph G.; Rogers, John A.

2011-01-01

Properties that can now be achieved with advanced, blue indium gallium nitride light emitting diodes (LEDs) lead to their potential as replacements for existing infrastructure in general illumination, with important implications for efficient use of energy. Further advances in this technology will benefit from reexamination of the modes for incorporating this materials technology into lighting modules that manage light conversion, extraction, and distribution, in ways that minimize adverse thermal effects associated with operation, with packages that exploit the unique aspects of these light sources. We present here ideas in anisotropic etching, microscale device assembly/integration, and module configuration that address these challenges in unconventional ways. Various device demonstrations provide examples of the capabilities, including thin, flexible lighting “tapes” based on patterned phosphors and large collections of small light emitters on plastic substrates. Quantitative modeling and experimental evaluation of heat flow in such structures illustrates one particular, important aspect of their operation: small, distributed LEDs can be passively cooled simply by direct thermal transport through thin-film metallization used for electrical interconnect, providing an enhanced and scalable means to integrate these devices in modules for white light generation. PMID:21666096

Self-regulated compliance in preschoolers with autism spectrum disorder: The role of temperament and parental disciplinary style.

PubMed

Ostfeld-Etzion, Sharon; Feldman, Ruth; Hirschler-Guttenberg, Yael; Laor, Nathaniel; Golan, Ofer

2016-10-01

Regulatory difficulties are common in children with autism spectrum disorder. This study focused on an important aspect of self-regulation-the ability to willingly comply with frustrating demands of socialization agents, termed "self-regulated compliance." We studied compliance to parental demands in 40 preschoolers with autism spectrum disorder and 40 matched typically developing preschoolers, during separate interactions with mother and father, while engaging in two paradigms: toy pick-up and delayed gratification, which tap the "do" and "don't" aspects of self-regulated socialization at this age. Parents' disciplinary style was micro-coded from the two paradigms and child temperament was parent reported. Compared to their typically developing peers, children with autism spectrum disorder showed more noncompliance and less self-regulated compliance to parental demands and prohibitions and greater temperamental difficulties across several domains. No group differences were found in parental disciplinary style. Child self-regulated compliance was associated with parental supportive disciplinary style and with child attention focusing. Findings highlight the importance of parental supportive presence in structuring the development of socialization in children with autism spectrum disorder. Implications for parent-child emotion regulation interventions are discussed. © The Author(s) 2015.

Exploring Helpful Nursing Care in Pediatric Mental Health Settings: The Perceptions of Children with Suicide Risk Factors and Their Parents.

PubMed

Montreuil, Marjorie; Butler, Kat J D; Stachura, Michal; Pugnaire Gros, Catherine

2015-01-01

This qualitative descriptive study explored helpful nursing care from the perspective of children with suicide-associated risk factors, and their parents. Data were collected through participant observation followed by a debriefing session with children, and semi-structured interviews with parents. The inductive analysis revealed four themes of helpful interventions: (1) caring for the child as a special person; (2) caring for the parents; (3) managing the child's illness; and (4) creating a therapeutic environment. The study findings highlight the importance of the relational aspect of nursing care and provide important insights related to family-centered and strengths-based practice with children at increased risk for suicide later in life.

Plant protection in Poland on the eve of obligatory integrated pest management implementation.

PubMed

Matyjaszczyk, Ewa

2013-09-01

Integrated pest management (IPM) will be obligatory in all European Union (EU) member states from January 1, 2014. Successful IPM implementation will depend not only on the sound guidelines and goodwill of the farmers, but also on conditions in farmers' environment. This paper presents the most important factors influencing IPM implementation in Poland. The most favorable aspects on the eve of obligatory IPM implementation are the relatively low use of plant protection products and popularity of some non-chemical methods of pest control, such as sowing cereal in mixture. The most important challenges are the improvement of advisory service and the crop structure with almost three-quarters of sown area covered by cereals. © 2013 Society of Chemical Industry.

Direct DNA binding by Brca1.

PubMed

Paull, T T; Cortez, D; Bowers, B; Elledge, S J; Gellert, M

2001-05-22

The tumor suppressor Brca1 plays an important role in protecting mammalian cells against genomic instability, but little is known about its modes of action. In this work we demonstrate that recombinant human Brca1 protein binds strongly to DNA, an activity conferred by a domain in the center of the Brca1 polypeptide. As a result of this binding, Brca1 inhibits the nucleolytic activities of the Mre11/Rad50/Nbs1 complex, an enzyme implicated in numerous aspects of double-strand break repair. Brca1 displays a preference for branched DNA structures and forms protein-DNA complexes cooperatively between multiple DNA strands, but without DNA sequence specificity. This fundamental property of Brca1 may be an important part of its role in DNA repair and transcription.

Personality expression in Chinese language use.

PubMed

Qiu, Lin; Lu, Jiahui; Ramsay, Jonathan; Yang, Shanshan; Qu, Weina; Zhu, Tingshao

2017-12-01

To date, little research has investigated personality expressions in languages other than English. Given that the Chinese language has the largest number of native speakers in the world, it is vitally important to examine the associations between personality and Chinese language use. In this research, we analysed Chinese microblogs and identified word categories and factorial structures associated with personality traits. We also compared our results with previous findings in English and showed that linguistic expression of personality has both universal- and language-specific aspects. Expression of personality via content words is more likely to be consistent across languages than expression via function words. This makes an important step towards uncovering universal patterns of personality expression in language. © 2016 International Union of Psychological Science.

Is It All about Money? Work Characteristics and Women's and Men's Marriage Formation in Early Adulthood.

PubMed

Kuo, Janet Chen-Lan; Raley, R Kelly

2016-06-01

Using data from the NLSY 97, this paper investigates how work characteristics (earnings and autonomy) shape young adults' transition to first marriage separately for men and women. The results suggest that earnings are positively associated with marriage and that this association is as strong for women as men in their mid-to-late twenties. Additionally, occupational autonomy-having the control over one's own work structure-facilitates entry into first marriage for women in their mid-to late-20s but, for men, occupational autonomy is not associated with marriage at these ages. These results suggest that even as women's earnings are increasingly important for marriage, other aspects of work are also important for stable family formation.

Division site selection in Escherichia coli involves dynamic redistribution of Min proteins within coiled structures that extend between the two cell poles

NASA Astrophysics Data System (ADS)

Shih, Yu-Ling; Le, Trung; Rothfield, Lawrence

2003-06-01

The MinCDE proteins of Escherichia coli are required for proper placement of the division septum at midcell. The site selection process requires the rapid oscillatory redistribution of the proteins from pole to pole. We report that the three Min proteins are organized into extended membrane-associated coiled structures that wind around the cell between the two poles. The pole-to-pole oscillation of the proteins reflects oscillatory changes in their distribution within the coiled structure. We also report that the E. coli MreB protein, which is required for maintaining the rod shape of the cell, also forms extended coiled structures, which are similar to the MreB structures that have previously been reported in Bacillus subtilis. The MreB and MinCDE coiled arrays do not appear identical. The results suggest that at least two functionally distinct cytoskeletal-like elements are present in E. coli and that structures of this type can undergo dynamic changes that play important roles in division site placement and possibly other aspects of the life of the cell.

A novel Multi-Agent Ada-Boost algorithm for predicting protein structural class with the information of protein secondary structure.

PubMed

Fan, Ming; Zheng, Bin; Li, Lihua

2015-10-01

Knowledge of the structural class of a given protein is important for understanding its folding patterns. Although a lot of efforts have been made, it still remains a challenging problem for prediction of protein structural class solely from protein sequences. The feature extraction and classification of proteins are the main problems in prediction. In this research, we extended our earlier work regarding these two aspects. In protein feature extraction, we proposed a scheme by calculating the word frequency and word position from sequences of amino acid, reduced amino acid, and secondary structure. For an accurate classification of the structural class of protein, we developed a novel Multi-Agent Ada-Boost (MA-Ada) method by integrating the features of Multi-Agent system into Ada-Boost algorithm. Extensive experiments were taken to test and compare the proposed method using four benchmark datasets in low homology. The results showed classification accuracies of 88.5%, 96.0%, 88.4%, and 85.5%, respectively, which are much better compared with the existing methods. The source code and dataset are available on request.

Development of the Main Wing Structure of a High Altitude Long Endurance UAV

NASA Astrophysics Data System (ADS)

Park, Sang Wook; Shin, Jeong Woo; Kim, Tae-Uk

2018-04-01

To enhance the flight endurance of a HALE UAV, the main wing of the UAV should have a high aspect ratio and low structural weight. Since a main wing constructed with the thin walled and slender components needed for low structural weight can suffer catastrophic failure during flight, it is important to develop a light-weight airframe without sacrificing structural integrity. In this paper, the design of the main wing of the HALE UAV was conducted using spars which were composed of a carbon-epoxy cylindrical tube and bulkheads to achieve both the weight reduction and structural integrity. The spars were sized using numerical analysis considering non-linear deformation under bending moment. Static strength testing of the wing was conducted under the most critical load condition. Then, the experimental results obtained for the wing were compared to the analytical result from the non-linear finite-element analysis. It was found that the developed main wing reduced its structural weight without any failure under the ultimate load condition of the static strength testing.

Description of New Inflatable/Rigidizable Hexapod Structure Testbed for Shape and Vibration Control

NASA Technical Reports Server (NTRS)

Adetona, O.; Keel, L. H.; Horta, L. G.; Cadogan, D. P.; Sapna, G. H.; Scarborough, S. E.

2002-01-01

Larger and more powerful space based instruments are needed to meet increasingly sophisticated scientific demand. To support this need, concepts for telescopes with apertures of 100 meters are being investigated, but the required technologies are not in hand today. Due to the capacity limits of launch vehicles, the idea of deploying, erecting, or inflating large structures in space is being considered. Recently, rigidization concepts of large inflatable structures have demonstrated the capability of weight reductions of up to 50% from current concepts with packaging efficiencies near 80%. One of the important aspects of inflatable structures is vibration mitigation and line-of-sight control. Such control tasks are possible only after actuators/sensors are properly integrated into a rigidizable concept. To study these issues, we have developed an inflatable/rigidizable hexapod structure testbed. The testbed integrates state of the art piezo-electric self-sensing actuators into an inflatable/rigidizable structure and a flat membrane reflector. Using this testbed, we plan to experimentally demonstrate achievable vibration and line-of-sight control. This paper contains a description of the testbed and an outline of the test plan.

Associated with aerospace vehicles development of methodologies for the estimation of thermal properties

NASA Technical Reports Server (NTRS)

Scott, Elaine P.

1994-01-01

Thermal stress analyses are an important aspect in the development of aerospace vehicles at NASA-LaRC. These analyses require knowledge of the temperature distributions within the vehicle structures which consequently necessitates the need for accurate thermal property data. The overall goal of this ongoing research effort is to develop methodologies for the estimation of the thermal property data needed to describe the temperature responses of these complex structures. The research strategy undertaken utilizes a building block approach. The idea here is to first focus on the development of property estimation methodologies for relatively simple conditions, such as isotropic materials at constant temperatures, and then systematically modify the technique for the analysis of more and more complex systems, such as anisotropic multi-component systems. The estimation methodology utilized is a statistically based method which incorporates experimental data and a mathematical model of the system. Several aspects of this overall research effort were investigated during the time of the ASEE summer program. One important aspect involved the calibration of the estimation procedure for the estimation of the thermal properties through the thickness of a standard material. Transient experiments were conducted using a Pyrex standard at various temperatures, and then the thermal properties (thermal conductivity and volumetric heat capacity) were estimated at each temperature. Confidence regions for the estimated values were also determined. These results were then compared to documented values. Another set of experimental tests were conducted on carbon composite samples at different temperatures. Again, the thermal properties were estimated for each temperature, and the results were compared with values obtained using another technique. In both sets of experiments, a 10-15 percent off-set between the estimated values and the previously determined values was found. Another effort was related to the development of the experimental techniques. Initial experiments required a resistance heater placed between two samples. The design was modified such that the heater was placed on the surface of only one sample, as would be necessary in the analysis of built up structures. Experiments using the modified technique were conducted on the composite sample used previously at different temperatures. The results were within 5 percent of those found using two samples. Finally, an initial heat transfer analysis, including conduction, convection and radiation components, was completed on a titanium sandwich structural sample. Experiments utilizing this sample are currently being designed and will be used to first estimate the material's effective thermal conductivity and later to determine the properties associated with each individual heat transfer component.

How Important Is Intrinsic Spirituality in Depression Care?

PubMed Central

Cooper, Lisa A; Brown, Charlotte; Thi Vu, Hong; Ford, Daniel E; Powe, Neil R

2001-01-01

We used a cross-sectional survey to compare the views of African-American and white adult primary care patients (N = 76) regarding the importance of various aspects of depression care. Patients were asked to rate the importance of 126 aspects of depression care (derived from attitudinal domains identified in focus groups) on a 5-point Likert scale. The 30 most important items came from 9 domains: 1) health professionals' interpersonal skills, 2) primary care provider recognition of depression, 3) treatment effectiveness, 4) treatment problems, 5) patient understanding about treatment, 6) intrinsic spirituality, 7) financial access, 8) life experiences, and 9) social support. African-American and white patients rated most aspects of depression care as similarly important, except that the odds of rating spirituality as extremely important for depression care were 3 times higher for African Americans than the odds for whites. PMID:11556945

The association of lifetime suicidal ideation with perceived parental love and family structure in childhood in a nationally representative adult sample.

PubMed

Susukida, Ryoko; Wilcox, Holly C; Mendelson, Tamar

2016-03-30

While perceived support from caregivers in the early stages of life is an aspect of family environment that is increasingly recognized as important for understanding lifetime suicidal behaviors, it is not well understood whether the relationship between perceived support from caregivers during childhood and lifetime suicidal behaviors holds regardless of family structure. This study examined the association between perceived love from caregivers in childhood and lifetime suicidal ideation in the National Comorbidity Survey Replication (N=5,692, 2001-2003). Multivariable logistic regression analyses were conducted to examine the association between lifetime suicidal ideation and retrospectively ascertained data on perceived love from caregivers during childhood as well as clinical and sociodemographic characteristics of study participants. Regression analyses were stratified by family structure, namely, whether or not study participants lived with two biological parents during childhood. Regardless of whether or not they lived with two biological parents during childhood, individuals who perceived love from caregivers during childhood had significantly 42-43% lower odds of lifetime suicide ideation as compared with those who did not perceive love from caregivers. Results suggest that perceived support from caregivers during childhood is an important correlate of lifetime suicidal ideation, regardless of family structure. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Disentangling the role of management, vegetation structure, and plant quality for Orthoptera in lowland meadows.

PubMed

Schirmel, Jens; Gerlach, Rebekka; Buhk, Constanze

2017-08-17

Seminatural grasslands provide habitats for various species and are important for biodiversity conservation. The understanding of the diverse responses of species and traits to different grassland management methods is therefore urgently needed. We disentangled the role of grassland management (fertilization and irrigation), vegetation structure (biomass, sward height) and plant quality (protein and fiber content) for Orthoptera communities in lowland hay meadows in Germany. We found vegetation structure to be the most important environmental category in explaining community structure of Orthoptera (species richness, total individuals, functional diversity and species composition). Intensively used meadows (fertilized, irrigated, high plant biomass) were characterized by assemblages with few species, low functional diversity, and low conservation value. Thereby, the relatively moderate fertilizer inputs in our study system of up to ∼75 kg N/ha/year reduced functional diversity of Orthoptera, while this negative effect of fertilization was not detectable when solely considering taxonomic aspects. We found strong support for a prominent role of plant quality in shaping Orthoptera communities and especially the trait composition. Our findings demonstrate the usefulness of considering both taxonomic and functional components (functional diversity) in biodiversity research and we suggest a stronger involvement of plant quality measures in Orthoptera studies. © 2017 Institute of Zoology, Chinese Academy of Sciences.

Structural model to evaluate the effect of participation and satisfaction on ecotourism sustainability

NASA Astrophysics Data System (ADS)

Kencana, Eka N.; Manutami, T.

2017-10-01

This paper is directed to study the effect of local community participation and visitors’ satisfaction on ecotourism sustainability at Badung regency of Bali province, Indonesia. Two important aspects regarding ecotourism sustainability had been studied, i.e. (a) economic benefits for local people and (b) tourists’ satisfaction. Applying variance-based structural equation modeling, data were collected in July 2015 from local community leaders of Kiadan Village at Badung regency and tourists whom visited this village, were analysed. Four latent variables, namely (a) community participation, (b) economic benefits, (c) tourists’ satisfaction, and (d) ecotourism sustainability, were used to build structural model. The results showed sustainability of Kiadan’s ecotourism was significantly affected by local community participation and visitors’ satisfaction although community participation’s effect slightly greater than tourists’ satisfaction with path values for participation and satisfaction as much as 0.651 and 0.627, respectively.

Evaluation of nonmetallic thermal protection materials for the manned space shuttle. Volume 1, task 1: Assessment of technical risks associated with utilization of nonmetallic thermal protection system

NASA Technical Reports Server (NTRS)

Wilkinson, W. H.; Kirkhart, F. P.; Kistler, C. W.; Duckworth, W. H.; Ungar, E. W.; Foster, E. L.

1970-01-01

Technical problems of design and flight qualification of the proposed classes of surface insulation materials and leading edge materials were reviewed. A screening test plan, a preliminary design data test plan and a design data test plan were outlined. This program defined the apparent critical differences between the surface insulators and the leading edge materials, structuring specialized screening test plans for each of these two classes of materials. Unique testing techniques were shown to be important in evaluating the structural interaction aspects of the surface insulators and a separate task was defined to validate the test plan. In addition, a compilation was made of available information on proposed material (including metallic TPS), previous shuttle programs, pertinent test procedures, and other national programs of merit. This material was collected and summarized in an informally structured workbook.

The Features of Self-Assembling Organic Bilayers Important to the Formation of Anisotropic Inorganic Materials in Microgravity Conditions

NASA Technical Reports Server (NTRS)

Talham, Daniel R.; Adair, James H.

1999-01-01

There is a growing need for inorganic anisotropic particles in a variety of materials science applications. Structural, optical, and electrical properties can be greatly augmented by the fabrication of composite materials with anisotropic microstructures or with anisotropic particles uniformly dispersed in an isotropic matrix. Examples include structural composites, magnetic and optical recording media, photographic film, certain metal and ceramic alloys, and display technologies including flat panel displays. While considerable progress has been made toward developing an understanding of the synthesis of powders composed of monodispersed, spherical particles, these efforts have not been transferred to the synthesis of anisotropic nanoparticles. The major objective of the program is to develop a fundamental understanding of the growth of anisotropic particles at organic templates, with emphasis on the chemical and structural aspects of layered organic assemblies that contribute to the formation of anisotropic inorganic particles.

A conceptual modeling framework for discrete event simulation using hierarchical control structures.

PubMed

Furian, N; O'Sullivan, M; Walker, C; Vössner, S; Neubacher, D

2015-08-01

Conceptual Modeling (CM) is a fundamental step in a simulation project. Nevertheless, it is only recently that structured approaches towards the definition and formulation of conceptual models have gained importance in the Discrete Event Simulation (DES) community. As a consequence, frameworks and guidelines for applying CM to DES have emerged and discussion of CM for DES is increasing. However, both the organization of model-components and the identification of behavior and system control from standard CM approaches have shortcomings that limit CM's applicability to DES. Therefore, we discuss the different aspects of previous CM frameworks and identify their limitations. Further, we present the Hierarchical Control Conceptual Modeling framework that pays more attention to the identification of a models' system behavior, control policies and dispatching routines and their structured representation within a conceptual model. The framework guides the user step-by-step through the modeling process and is illustrated by a worked example.

Dynamic test/analysis correlation using reduced analytical models

NASA Technical Reports Server (NTRS)

Mcgowan, Paul E.; Angelucci, A. Filippo; Javeed, Mehzad

1992-01-01

Test/analysis correlation is an important aspect of the verification of analysis models which are used to predict on-orbit response characteristics of large space structures. This paper presents results of a study using reduced analysis models for performing dynamic test/analysis correlation. The reduced test-analysis model (TAM) has the same number and orientation of DOF as the test measurements. Two reduction methods, static (Guyan) reduction and the Improved Reduced System (IRS) reduction, are applied to the test/analysis correlation of a laboratory truss structure. Simulated test results and modal test data are used to examine the performance of each method. It is shown that selection of DOF to be retained in the TAM is critical when large structural masses are involved. In addition, the use of modal test results may provide difficulties in TAM accuracy even if a large number of DOF are retained in the TAM.

Structure and effective interactions in three-component hard sphere liquids.

PubMed

König, A; Ashcroft, N W

2001-04-01

Complete and simple analytical expressions for the partial structure factors of the ternary hard sphere mixture are obtained within the Percus-Yevick approximation and presented as functions of relative packing fractions and relative hard sphere diameters. These solutions follow from the Laplace transform method as applied to multicomponent systems by Lebowitz [Phys. Rev. 133, A895 (1964)]. As an important application, we examine effective interactions in hard sphere liquid mixtures using the microscopic information contained in their partial structure factors. Thus the ensuring pair potential for an effective one-component system is obtained from the correlation functions by using an approximate inversion, and examples of effective potentials for three-component hard sphere mixtures are given. These mixtures may be of particular interest for the study of the packing aspects of melts that form glasses or quasicrystals, since noncrystalline solids often emerge from melts with at least three atomic constituents.

Aircraft Interior Noise Control Using Distributed Piezoelectric Actuators

NASA Technical Reports Server (NTRS)

Sun, Jian Q.

1996-01-01

Developing a control system that can reduce the noise and structural vibration at the same time is an important task. This talk presents one possible technical approach for accomplishing this task. The target application of the research is for aircraft interior noise control. The emphasis of the present approach is not on control strategies, but rather on the design of actuators for the control system. In the talk, a theory of distributed piezoelectric actuators is introduced. A uniform cylindrical shell is taken as a simplified model of fuselage structures to illustrate the effectiveness of the design theory. The actuators developed are such that they can reduce the tonal structural vibration and interior noise in a wide range of frequencies. Extensive computer simulations have been done to study various aspects of the design theory. Experiments have also been conducted and the test results strongly support the theoretical development.

A conceptual modeling framework for discrete event simulation using hierarchical control structures

PubMed Central

Furian, N.; O’Sullivan, M.; Walker, C.; Vössner, S.; Neubacher, D.

2015-01-01

Conceptual Modeling (CM) is a fundamental step in a simulation project. Nevertheless, it is only recently that structured approaches towards the definition and formulation of conceptual models have gained importance in the Discrete Event Simulation (DES) community. As a consequence, frameworks and guidelines for applying CM to DES have emerged and discussion of CM for DES is increasing. However, both the organization of model-components and the identification of behavior and system control from standard CM approaches have shortcomings that limit CM’s applicability to DES. Therefore, we discuss the different aspects of previous CM frameworks and identify their limitations. Further, we present the Hierarchical Control Conceptual Modeling framework that pays more attention to the identification of a models’ system behavior, control policies and dispatching routines and their structured representation within a conceptual model. The framework guides the user step-by-step through the modeling process and is illustrated by a worked example. PMID:26778940

Toward a comprehensive taxonomy of human motives

PubMed Central

Talevich, Jennifer R.; Walsh, David A.; Iyer, Ravi; Chopra, Gurveen

2017-01-01

A major success in personality has been the development of a consensual structure of traits. However, much less progress has been made on the structure of an equally important aspect of human psychology: motives. We present an empirically and theoretically structured hierarchical taxonomy of 161 motives gleaned from a literature review from McDougall to the present and based on the cluster analysis of similarity judgments among these 161 motives, a broader sampling of motives than previous work. At the broadest level were: Meaning, Communion, and Agency. These divided into nine clusters: Morality & Virtue, Religion & Spirituality, Self-Actualization, Avoidance, Social Relating, Family, Health, Mastery & Competence, and Financial & Occupational Success. Each divided into more concrete clusters to form 5 levels. We discuss contributions to research on motives, especially recent work on goal systems, and the aiding of communication and systematization of research. Finally, we compare the taxonomy to other motive organizations. PMID:28231252

Analysis and measurements of low frequency lightning component penetration through aerospace vehicle metal and graphite skins

NASA Technical Reports Server (NTRS)

Robb, J. D.; Chen, T.

1980-01-01

An analysis of the shielding properties of mixed metal and graphite composite structures has illustrated some important aspects of electromagnetic field penetration into the interior. These include: (1) that graphite access doors on metallic structures will attenuate lightning magnetic fields very little; conversely, metal doors on a graphite structure will also attenuate fields from lightning strike currents very little, i.e., homogeneity of the shield is a critical factor in shielding and (2) that continuous conductors between two points inside a graphite skin such as an air data probe metallic tubing connection to an air data computer can allow large current penetrations into a vehicle interior. The true weight savings resulting from the use of composite materials can only be evaluated after the resulting electromagnetic problems such as current penetrations have been solved, and this generally requires weight addition in the form of cable shields, conductor bonding or external metallization.

Demographic and settlement transformations in peripheral regions (based on the example of eastern Poland)

NASA Astrophysics Data System (ADS)

Miszczuk, Andrzej; Wesołowska, Monika

2012-01-01

The aim of this article is to show specific demographic processes and accompanied transformations of settlement structure in eastern Poland at the turn of the 21st cent. Eastern Poland, covering Lubelskie, Podkarpackie, Podlaskie, Świętokrzyskie and Warmińsko-Mazurskie voivodeships, acquired the features of peripheral area in terms of communication and socio-economic aspects as a result of long-lasting historical processes. Unfavourable demographic processes can be observed in eastern Poland. They are accompanied by changes in settlement structure. Depopulation has significant social and economic consequences. The process increases social polarization between different regions in the country and between rural and urban areas. Moreover, the outflow of young and most active population to other regions or abroad is an important barrier for economic revival in peripheral regions. Consequently, unfavourable socio-economic structure in these areas is consolidated or even strengthened. This primarily concerns Lubelskie and Podlaskie voivodeships.

Self-organizing linear output map (SOLO): An artificial neural network suitable for hydrologic modeling and analysis

NASA Astrophysics Data System (ADS)

Hsu, Kuo-Lin; Gupta, Hoshin V.; Gao, Xiaogang; Sorooshian, Soroosh; Imam, Bisher

2002-12-01

Artificial neural networks (ANNs) can be useful in the prediction of hydrologic variables, such as streamflow, particularly when the underlying processes have complex nonlinear interrelationships. However, conventional ANN structures suffer from network training issues that significantly limit their widespread application. This paper presents a multivariate ANN procedure entitled self-organizing linear output map (SOLO), whose structure has been designed for rapid, precise, and inexpensive estimation of network structure/parameters and system outputs. More important, SOLO provides features that facilitate insight into the underlying processes, thereby extending its usefulness beyond forecast applications as a tool for scientific investigations. These characteristics are demonstrated using a classic rainfall-runoff forecasting problem. Various aspects of model performance are evaluated in comparison with other commonly used modeling approaches, including multilayer feedforward ANNs, linear time series modeling, and conceptual rainfall-runoff modeling.

When I Call You Up and You're Not There: Application of Communication Accommodation Theory to Telephone Answering Machine Messages.

ERIC Educational Resources Information Center

Buzzanell, Patrice M.; And Others

1996-01-01

Explores whether telephone callers converge to structural and relational message aspects found in recorded answering machine messages. Finds that callers exhibited greater convergence to relational than to structural aspects, and that both female and male callers converged with levels of immediacy in answering machine messages. Outlines…

Architecture of the sperm whale forehead facilitates ramming combat.

PubMed

Panagiotopoulou, Olga; Spyridis, Panagiotis; Mehari Abraha, Hyab; Carrier, David R; Pataky, Todd C

2016-01-01

Herman Melville's novel Moby Dick was inspired by historical instances in which large sperm whales (Physeter macrocephalus L.) sank 19th century whaling ships by ramming them with their foreheads. The immense forehead of sperm whales is possibly the largest, and one of the strangest, anatomical structures in the animal kingdom. It contains two large oil-filled compartments, known as the "spermaceti organ" and "junk," that constitute up to one-quarter of body mass and extend one-third of the total length of the whale. Recognized as playing an important role in echolocation, previous studies have also attributed the complex structural configuration of the spermaceti organ and junk to acoustic sexual selection, acoustic prey debilitation, buoyancy control, and aggressive ramming. Of these additional suggested functions, ramming remains the most controversial, and the potential mechanical roles of the structural components of the spermaceti organ and junk in ramming remain untested. Here we explore the aggressive ramming hypothesis using a novel combination of structural engineering principles and probabilistic simulation to determine if the unique structure of the junk significantly reduces stress in the skull during quasi-static impact. Our analyses indicate that the connective tissue partitions in the junk reduce von Mises stresses across the skull and that the load-redistribution functionality of the former is insensitive to moderate variation in tissue material parameters, the thickness of the partitions, and variations in the location and angle of the applied load. Absence of the connective tissue partitions increases skull stresses, particularly in the rostral aspect of the upper jaw, further hinting of the important role the architecture of the junk may play in ramming events. Our study also found that impact loads on the spermaceti organ generate lower skull stresses than an impact on the junk. Nevertheless, whilst an impact on the spermaceti organ would reduce skull stresses, it would also cause high compressive stresses on the anterior aspect of the organ and the connective tissue case, possibly making these structures more prone to failure. This outcome, coupled with the facts that the spermaceti organ houses sensitive and essential sonar producing structures and the rostral portion of junk, rather than the spermaceti organ, is frequently a site of significant scarring in mature males suggest that whales avoid impact with the spermaceti organ. Although the unique structure of the junk certainly serves multiple functions, our results are consistent with the hypothesis that the structure also evolved to function as a massive battering ram during male-male competition.

Shedding of dual structures in the wake of a surface-mounted low aspect ratio cone

NASA Astrophysics Data System (ADS)

Chen, Zixiang; Martinuzzi, Robert J.

2018-04-01

The periodic shedding of vortex pairs in the turbulent wake of a surface-mounted right cone of aspect ratio 0.867 protruding a thin turbulent boundary layer is investigated experimentally. A phase-averaged volumetric velocity field is reconstructed from planar stereoscopic particle image velocimetry. During a typical (phase-averaged) shedding cycle, counter-rotating base vortices alternately form. These are tilted and stretched to merge with stream-wise tip vortices. The merged structure sheds and is convected downstream. A synthesis of earlier observations suggests that a similar shedding process exists for other low aspect ratio tapered geometries and is more complex than the shedding patterns observed for cantilevered cylinders, despite similarities of the mean flow field structure.

Mapping accuracy via spectrally and structurally based filtering techniques: comparisons through visual observations

NASA Astrophysics Data System (ADS)

Chockalingam, Letchumanan

2005-01-01

The data of Gunung Ledang region of Malaysia acquired through LANDSAT are considered to map certain hydrogeolocial features. To map these significant features, image-processing tools such as contrast enhancement, edge detection techniques are employed. The advantages of these techniques over the other methods are evaluated from the point of their validity in properly isolating features of hydrogeolocial interest are discussed. As these techniques take the advantage of spectral aspects of the images, these techniques have several limitations to meet the objectives. To discuss these limitations, a morphological transformation, which generally considers the structural aspects rather than spectral aspects from the image, are applied to provide comparisons between the results derived from spectral based and the structural based filtering techniques.

Deformation mechanisms in negative Poisson's ratio materials - Structural aspects

NASA Technical Reports Server (NTRS)

Lakes, R.

1991-01-01

Poisson's ratio in materials is governed by the following aspects of the microstructure: the presence of rotational degrees of freedom, non-affine deformation kinematics, or anisotropic structure. Several structural models are examined. The non-affine kinematics are seen to be essential for the production of negative Poisson's ratios for isotropic materials containing central force linkages of positive stiffness. Non-central forces combined with pre-load can also give rise to a negative Poisson's ratio in isotropic materials. A chiral microstructure with non-central force interaction or non-affine deformation can also exhibit a negative Poisson's ratio. Toughness and damage resistance in these materials may be affected by the Poisson's ratio itself, as well as by generalized continuum aspects associated with the microstructure.

Isolation by environmental distance in mobile marine species: molecular ecology of franciscana dolphins at their southern range.

PubMed

Mendez, Martin; Rosenbaum, Howard C; Subramaniam, Ajit; Yackulic, Charles; Bordino, Pablo

2010-06-01

The assessment of population structure is a valuable tool for studying the ecology of endangered species and drafting conservation strategies. As we enhance our understanding about the structuring of natural populations, it becomes important that we also understand the processes behind these patterns. However, there are few rigorous assessments of the influence of environmental factors on genetic patterns in mobile marine species. Given their dispersal capabilities and localized habitat preferences, coastal cetaceans are adequate study species for evaluating environmental effects on marine population structure. The franciscana dolphin, a rare coastal cetacean endemic to the Western South Atlantic, was studied to examine these issues. We analysed genetic data from the mitochondrial DNA and 12 microsatellite markers for 275 franciscana samples utilizing frequency-based, maximum-likelihood and Bayesian algorithms to assess population structure and migration patterns. This information was combined with 10 years of remote sensing environmental data (chlorophyll concentration, water turbidity and surface temperature). Our analyses show the occurrence of genetically isolated populations within Argentina, in areas that are environmentally distinct. Combined evidence of genetic and environmental structure suggests that isolation by distance and a process here termed isolation by environmental distance can explain the observed correlations. Our approach elucidated important ecological and conservation aspects of franciscana dolphins, and has the potential to increase our understanding of ecological processes influencing genetic patterns in other marine species.

Linking structure, process, and outcome to improve group home services for foster youth in California.

PubMed

Green, Rex S; Ellis, Peter T

2007-08-01

The California Youth Connection obtained funding from two foundations to evaluate the performance of group homes serving foster youth in Alameda County, California, in order to inform state policy-making. The evaluation team initially included 14 foster youth that personally experienced group home living. Three inter-related aspects of service were studied: structure, process, and client outcomes, specifically residents' increase in developmental assets leading to the ability to transition successfully to independent living by the age of 18 years. Data were collected at 32 group homes from 127 residents and 72 staff members using three questionnaires. Both structural and process aspects of services influenced residents' satisfaction with services. However, only the process of care predicted changes in residents' developmental assets. State-level regulatory agencies learned from these results that auditing only structural aspects of services was not sufficient to promote effective services. Further, one structure item and two process items were identified as less consistently occurring in the group homes: timely distribution of clothing allowances, healthy communication between staff and youth, and staff support of regular exercise for the residents. Focusing on these aspects of service first should promote more change in outcomes and satisfaction for foster youth residing in group homes.

Front propagation in a regular vortex lattice: Dependence on the vortex structure.

PubMed

Beauvier, E; Bodea, S; Pocheau, A

2017-11-01

We investigate the dependence on the vortex structure of the propagation of fronts in stirred flows. For this, we consider a regular set of vortices whose structure is changed by varying both their boundary conditions and their aspect ratios. These configurations are investigated experimentally in autocatalytic solutions stirred by electroconvective flows and numerically from kinematic simulations based on the determination of the dominant Fourier mode of the vortex stream function in each of them. For free lateral boundary conditions, i.e., in an extended vortex lattice, it is found that both the flow structure and the front propagation negligibly depend on vortex aspect ratios. For rigid lateral boundary conditions, i.e., in a vortex chain, vortices involve a slight dependence on their aspect ratios which surprisingly yields a noticeable decrease of the enhancement of front velocity by flow advection. These different behaviors reveal a sensitivity of the mean front velocity on the flow subscales. It emphasizes the intrinsic multiscale nature of front propagation in stirred flows and the need to take into account not only the intensity of vortex flows but also their inner structure to determine front propagation at a large scale. Differences between experiments and simulations suggest the occurrence of secondary flows in vortex chains at large velocity and large aspect ratios.

New phenotypic aspects of the decidual spiral artery wall during early post-implantation mouse pregnancy

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

Elia, Artemis; Charalambous, Fotini; Georgiades, Pantelis, E-mail: pgeor@ucy.ac.cy

Highlights: Black-Right-Pointing-Pointer Spiral artery (SA) wall remodeling (SAR) is ill-defined and clinically important. Black-Right-Pointing-Pointer SA muscular phenotype prior to and during SAR in mice is underexplored. Black-Right-Pointing-Pointer SA muscular wall consists of contractile and non-contractile components. Black-Right-Pointing-Pointer SA wall non-contractile component may be synthetic smooth muscle. Black-Right-Pointing-Pointer Timing and extent of SA wall contractile component loss is revealed. -- Abstract: During pregnancy the walls of decidual spiral arteries (SAs) undergo clinically important structural modifications crucial for embryo survival/growth and maternal health. However, the mechanisms of SA remodeling (SAR) are poorly understood. Although an important prerequisite to this understanding is knowledgemore » about the phenotype of SA muscular wall prior to and during the beginning of mouse SAR, this remains largely unexplored and was the main aim of this work. Using histological and immunohistochemical techniques, this study shows for the first time that during early mouse gestation, from embryonic day 7.5 (E7.5) to E10.5, the decidual SA muscular coat is not a homogeneous structure, but consists of two concentric layers. The first is a largely one cell-thick sub-endothelial layer of contractile mural cells (positive for {alpha}-smooth muscle actin, calponin and SM22{alpha}) with pericyte characteristics (NG2 positive). The second layer is thicker, and evidence is presented that it may be of the synthetic/proliferative smooth muscle phenotype, based on absence ({alpha}-smooth muscle actin and calponin) or weak (SM22{alpha}) expression of contractile mural cell markers, and presence of synthetic smooth muscle characteristics (expression of non-muscle Myosin heavy chain-IIA and of the cell proliferation marker PCNA). Importantly, immunohistochemistry and morphometrics showed that the contractile mural cell layer although prominent at E7.5-E8.5, becomes drastically reduced by E10.5 and is undetectable by E12.5. In conclusion, this study reveals novel aspects of the decidual SA muscular coat phenotype prior to and during early SAR that may have important implications for understanding the mechanisms of SAR.« less

The structural basis of secondary active transport mechanisms.

PubMed

Forrest, Lucy R; Krämer, Reinhard; Ziegler, Christine

2011-02-01

Secondary active transporters couple the free energy of the electrochemical potential of one solute to the transmembrane movement of another. As a basic mechanistic explanation for their transport function the model of alternating access was put forward more than 40 years ago, and has been supported by numerous kinetic, biochemical and biophysical studies. According to this model, the transporter exposes its substrate binding site(s) to one side of the membrane or the other during transport catalysis, requiring a substantial conformational change of the carrier protein. In the light of recent structural data for a number of secondary transport proteins, we analyze the model of alternating access in more detail, and correlate it with specific structural and chemical properties of the transporters, such as their assignment to different functional states in the catalytic cycle of the respective transporter, the definition of substrate binding sites, the type of movement of the central part of the carrier harboring the substrate binding site, as well as the impact of symmetry on fold-specific conformational changes. Besides mediating the transmembrane movement of solutes, the mechanism of secondary carriers inherently involves a mechanistic coupling of substrate flux to the electrochemical potential of co-substrate ions or solutes. Mainly because of limitations in resolution of available transporter structures, this important aspect of secondary transport cannot yet be substantiated by structural data to the same extent as the conformational change aspect. We summarize the concepts of coupling in secondary transport and discuss them in the context of the available evidence for ion binding to specific sites and the impact of the ions on the conformational state of the carrier protein, which together lead to mechanistic models for coupling. Copyright © 2010 Elsevier B.V. All rights reserved.

Differential efferent projections of the anterior, posteroventral, and posterodorsal subdivisions of the medial amygdala in mice

PubMed Central

Pardo-Bellver, Cecília; Cádiz-Moretti, Bernardita; Novejarque, Amparo; Martínez-García, Fernando; Lanuza, Enrique

2012-01-01

The medial amygdaloid nucleus (Me) is a key structure in the control of sociosexual behavior in mice. It receives direct projections from the main and accessory olfactory bulbs (AOB), as well as an important hormonal input. To better understand its behavioral role, in this work we investigate the structures receiving information from the Me, by analysing the efferent projections from its anterior (MeA), posterodorsal (MePD) and posteroventral (MePV) subdivisions, using anterograde neuronal tracing with biotinylated and tetrametylrhodamine-conjugated dextranamines. The Me is strongly interconnected with the rest of the chemosensory amygdala, but shows only moderate projections to the central nucleus and light projections to the associative nuclei of the basolateral amygdaloid complex. In addition, the MeA originates a strong feedback projection to the deep mitral cell layer of the AOB, whereas the MePV projects to its granule cell layer. The Me (especially the MeA) has also moderate projections to different olfactory structures, including the piriform cortex (Pir). The densest outputs of the Me target the bed nucleus of the stria terminalis (BST) and the hypothalamus. The MeA and MePV project to key structures of the circuit involved in the defensive response against predators (medial posterointermediate BST, anterior hypothalamic area, dorsomedial aspect of the ventromedial hypothalamic nucleus), although less dense projections also innervate reproductive-related nuclei. In contrast, the MePD projects mainly to structures that control reproductive behaviors [medial posteromedial BST, medial preoptic nucleus, and ventrolateral aspect of the ventromedial hypothalamic nucleus], although less dense projections to defensive-related nuclei also exist. These results confirm and extend previous results in other rodents and suggest that the medial amygdala is anatomically and functionally compartmentalized. PMID:22933993

Differential efferent projections of the anterior, posteroventral, and posterodorsal subdivisions of the medial amygdala in mice.

PubMed

Pardo-Bellver, Cecília; Cádiz-Moretti, Bernardita; Novejarque, Amparo; Martínez-García, Fernando; Lanuza, Enrique

2012-01-01

The medial amygdaloid nucleus (Me) is a key structure in the control of sociosexual behavior in mice. It receives direct projections from the main and accessory olfactory bulbs (AOB), as well as an important hormonal input. To better understand its behavioral role, in this work we investigate the structures receiving information from the Me, by analysing the efferent projections from its anterior (MeA), posterodorsal (MePD) and posteroventral (MePV) subdivisions, using anterograde neuronal tracing with biotinylated and tetrametylrhodamine-conjugated dextranamines. The Me is strongly interconnected with the rest of the chemosensory amygdala, but shows only moderate projections to the central nucleus and light projections to the associative nuclei of the basolateral amygdaloid complex. In addition, the MeA originates a strong feedback projection to the deep mitral cell layer of the AOB, whereas the MePV projects to its granule cell layer. The Me (especially the MeA) has also moderate projections to different olfactory structures, including the piriform cortex (Pir). The densest outputs of the Me target the bed nucleus of the stria terminalis (BST) and the hypothalamus. The MeA and MePV project to key structures of the circuit involved in the defensive response against predators (medial posterointermediate BST, anterior hypothalamic area, dorsomedial aspect of the ventromedial hypothalamic nucleus), although less dense projections also innervate reproductive-related nuclei. In contrast, the MePD projects mainly to structures that control reproductive behaviors [medial posteromedial BST, medial preoptic nucleus, and ventrolateral aspect of the ventromedial hypothalamic nucleus], although less dense projections to defensive-related nuclei also exist. These results confirm and extend previous results in other rodents and suggest that the medial amygdala is anatomically and functionally compartmentalized.

Structure, Biology, and Therapeutic Application of Toxin-Antitoxin Systems in Pathogenic Bacteria.

PubMed

Lee, Ki-Young; Lee, Bong-Jin

2016-10-22

Bacterial toxin-antitoxin (TA) systems have received increasing attention for their diverse identities, structures, and functional implications in cell cycle arrest and survival against environmental stresses such as nutrient deficiency, antibiotic treatments, and immune system attacks. In this review, we describe the biological functions and the auto-regulatory mechanisms of six different types of TA systems, among which the type II TA system has been most extensively studied. The functions of type II toxins include mRNA/tRNA cleavage, gyrase/ribosome poison, and protein phosphorylation, which can be neutralized by their cognate antitoxins. We mainly explore the similar but divergent structures of type II TA proteins from 12 important pathogenic bacteria, including various aspects of protein-protein interactions. Accumulating knowledge about the structure-function correlation of TA systems from pathogenic bacteria has facilitated a novel strategy to develop antibiotic drugs that target specific pathogens. These molecules could increase the intrinsic activity of the toxin by artificially interfering with the intermolecular network of the TA systems.

On Cognition, Structured Sequence Processing, and Adaptive Dynamical Systems

NASA Astrophysics Data System (ADS)

Petersson, Karl Magnus

2008-11-01

Cognitive neuroscience approaches the brain as a cognitive system: a system that functionally is conceptualized in terms of information processing. We outline some aspects of this concept and consider a physical system to be an information processing device when a subclass of its physical states can be viewed as representational/cognitive and transitions between these can be conceptualized as a process operating on these states by implementing operations on the corresponding representational structures. We identify a generic and fundamental problem in cognition: sequentially organized structured processing. Structured sequence processing provides the brain, in an essential sense, with its processing logic. In an approach addressing this problem, we illustrate how to integrate levels of analysis within a framework of adaptive dynamical systems. We note that the dynamical system framework lends itself to a description of asynchronous event-driven devices, which is likely to be important in cognition because the brain appears to be an asynchronous processing system. We use the human language faculty and natural language processing as a concrete example through out.

Structure of Salmonella FlhE, conserved member of a flagellar Type III secretion operon

DOE PAGES

Lee, Jaemin; Monzingo, Arthur F.; Keatinge-Clay, Adrian T.; ...

2014-12-26

In this paper, the bacterial flagellum is assembled by a multicomponent transport apparatus categorized as a type III secretion system. The secretion of proteins that assemble into the flagellum is driven by the proton motive force. The periplasmic protein FlhE is a member of the flhBAE operon in the majority of bacteria where FlhE is found. FlhA and FlhB are established components of the flagellar type III secretion system. The absence of FlhE results in a proton leak through the flagellar system, inappropriate secretion patterns, and cell death, indicating that FlhE regulates an important aspect of proper flagellar biosynthesis. Wemore » isolated FlhE from the periplasm of Salmonella and solved its structure to 1.5 Å resolution. The structure reveals a β-sandwich fold, with no close structural homologs. Finally, possible roles of FlhE, including that of a chaperone, are discussed.« less

Structure of Salmonella FlhE, conserved member of a flagellar Type III secretion operon

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

Lee, Jaemin; Monzingo, Arthur F.; Keatinge-Clay, Adrian T.

In this paper, the bacterial flagellum is assembled by a multicomponent transport apparatus categorized as a type III secretion system. The secretion of proteins that assemble into the flagellum is driven by the proton motive force. The periplasmic protein FlhE is a member of the flhBAE operon in the majority of bacteria where FlhE is found. FlhA and FlhB are established components of the flagellar type III secretion system. The absence of FlhE results in a proton leak through the flagellar system, inappropriate secretion patterns, and cell death, indicating that FlhE regulates an important aspect of proper flagellar biosynthesis. Wemore » isolated FlhE from the periplasm of Salmonella and solved its structure to 1.5 Å resolution. The structure reveals a β-sandwich fold, with no close structural homologs. Finally, possible roles of FlhE, including that of a chaperone, are discussed.« less

Emerging concepts in smooth muscle contributions to airway structure and function: implications for health and disease

PubMed Central

2016-01-01

Airway structure and function are key aspects of normal lung development, growth, and aging, as well as of lung responses to the environment and the pathophysiology of important diseases such as asthma, chronic obstructive pulmonary disease, and fibrosis. In this regard, the contributions of airway smooth muscle (ASM) are both functional, in the context of airway contractility and relaxation, as well as synthetic, involving production and modulation of extracellular components, modulation of the local immune environment, cellular contribution to airway structure, and, finally, interactions with other airway cell types such as epithelium, fibroblasts, and nerves. These ASM contributions are now found to be critical in airway hyperresponsiveness and remodeling that occur in lung diseases. This review emphasizes established and recent discoveries that underline the central role of ASM and sets the stage for future research toward understanding how ASM plays a central role by being both upstream and downstream in the many interactive processes that determine airway structure and function in health and disease. PMID:27742732

Toward increased autonomy in the surgical OR: needs, requests, and expectations.

PubMed

Kranzfelder, Michael; Staub, Christoph; Fiolka, Adam; Schneider, Armin; Gillen, Sonja; Wilhelm, Dirk; Friess, Helmut; Knoll, Alois; Feussner, Hubertus

2013-05-01

The current trend in surgery toward further trauma reduction inevitably leads to increased technological complexity. It must be assumed that this situation will not stay under the sole control of surgeons; mechanical systems will assist them. Certain segments of the work flow will likely have to be taken over by a machine in an automatized or autonomous mode. In addition to the analysis of our own surgical practice, a literature search of the Medline database was performed to identify important aspects, methods, and technologies for increased operating room (OR) autonomy. Robotic surgical systems can help to increase OR autonomy by camera control, application of intelligent instruments, and even accomplishment of automated surgical procedures. However, the important step from simple task execution to autonomous decision making is difficult to realize. Another important aspect is the adaption of the general technical OR environment. This includes adaptive OR setting and context-adaptive interfaces, automated tool arrangement, and optimal visualization. Finally, integration of peri- and intraoperative data consisting of electronic patient record, OR documentation and logistics, medical imaging, and patient surveillance data could increase autonomy. To gain autonomy in the OR, a variety of assistance systems and methodologies need to be incorporated that endorse the surgeon autonomously as a first step toward the vision of cognitive surgery. Thus, we require establishment of model-based surgery and integration of procedural tasks. Structured knowledge is therefore indispensable.