A statistical human resources costing and accounting model for analysing the economic effects of an intervention at a workplace.

PubMed

Landstad, Bodil J; Gelin, Gunnar; Malmquist, Claes; Vinberg, Stig

2002-09-15

The study had two primary aims. The first aim was to combine a human resources costing and accounting approach (HRCA) with a quantitative statistical approach in order to get an integrated model. The second aim was to apply this integrated model in a quasi-experimental study in order to investigate whether preventive intervention affected sickness absence costs at the company level. The intervention studied contained occupational organizational measures, competence development, physical and psychosocial working environmental measures and individual and rehabilitation measures on both an individual and a group basis. The study is a quasi-experimental design with a non-randomized control group. Both groups involved cleaning jobs at predominantly female workplaces. The study plan involved carrying out before and after studies on both groups. The study included only those who were at the same workplace during the whole of the study period. In the HRCA model used here, the cost of sickness absence is the net difference between the costs, in the form of the value of the loss of production and the administrative cost, and the benefits in the form of lower labour costs. According to the HRCA model, the intervention used counteracted a rise in sickness absence costs at the company level, giving an average net effect of 266.5 Euros per person (full-time working) during an 8-month period. Using an analogue statistical analysis on the whole of the material, the contribution of the intervention counteracted a rise in sickness absence costs at the company level giving an average net effect of 283.2 Euros. Using a statistical method it was possible to study the regression coefficients in sub-groups and calculate the p-values for these coefficients; in the younger group the intervention gave a calculated net contribution of 605.6 Euros with a p-value of 0.073, while the intervention net contribution in the older group had a very high p-value. Using the statistical model it was also possible to study contributions of other variables and interactions. This study established that the HRCA model and the integrated model produced approximately the same monetary outcomes. The integrated model, however, allowed a deeper understanding of the various possible relationships and quantified the results with confidence intervals.

Modeling Writing Development: Contribution of Transcription and Self-Regulation to Portuguese Students' Text Generation Quality

ERIC Educational Resources Information Center

Limpo, Teresa; Alves, Rui A.

2013-01-01

Writing is a complex activity that requires transcription and self-regulation. We used multiple-group structural equation modeling to test the contribution of transcription (handwriting and spelling), planning, revision, and self-efficacy to writing quality at 2 developmental points (Grades 4-6 vs. 7-9). In Grades 4-6, the model explained 76% of…

Explaining Cooperation in Groups: Testing Models of Reciprocity and Learning

ERIC Educational Resources Information Center

Biele, Guido; Rieskamp, Jorg; Czienskowski, Uwe

2008-01-01

What are the cognitive processes underlying cooperation in groups? This question is addressed by examining how well a reciprocity model, two learning models, and social value orientation can predict cooperation in two iterated n-person social dilemmas with continuous contributions. In the first of these dilemmas, the public goods game,…

Explaining trends in coronary heart disease mortality in different socioeconomic groups in Denmark 1991-2007 using the IMPACTSEC model

PubMed Central

Joergensen, Torben; Bandosz, Piotr; Hallas, Jesper; Prescott, Eva Irene Bossano; Capewell, Simon

2018-01-01

Aim To quantify the contribution of changes in different risk factors population levels and treatment uptake on the decline in CHD mortality in Denmark from 1991 to 2007 in different socioeconomic groups. Design We used IMPACTSEC, a previously validated policy model using data from different population registries. Participants All adults aged 25–84 years living in Denmark in 1991 and 2007. Main outcome measure Deaths prevented or postponed (DPP). Results There were approximately 11,000 fewer CHD deaths in Denmark in 2007 than would be expected if the 1991 mortality rates had persisted. Higher mortality rates were observed in the lowest socioeconomic quintile. The highest absolute reduction in CHD mortality was seen in this group but the highest relative reduction was in the most affluent socioeconomic quintile. Overall, the IMPACTSEC model explained nearly two thirds of the decline in. Improved treatments accounted for approximately 25% with the least relative mortality reduction in the most deprived quintile. Risk factor improvements accounted for approximately 40% of the mortality decrease with similar gains across all socio-economic groups. The 36% gap in explaining all DPPs may reflect inaccurate data or risk factors not quantified in the current model. Conclusions According to the IMPACTSEC model, the largest contribution to the CHD mortality decline in Denmark from 1991 to 2007 was from improvements in risk factors, with similar gains across all socio-economic groups. However, we found a clear socioeconomic trend for the treatment contribution favouring the most affluent groups. PMID:29672537

Predicting speech intelligibility with a multiple speech subsystems approach in children with cerebral palsy.

PubMed

Lee, Jimin; Hustad, Katherine C; Weismer, Gary

2014-10-01

Speech acoustic characteristics of children with cerebral palsy (CP) were examined with a multiple speech subsystems approach; speech intelligibility was evaluated using a prediction model in which acoustic measures were selected to represent three speech subsystems. Nine acoustic variables reflecting different subsystems, and speech intelligibility, were measured in 22 children with CP. These children included 13 with a clinical diagnosis of dysarthria (speech motor impairment [SMI] group) and 9 judged to be free of dysarthria (no SMI [NSMI] group). Data from children with CP were compared to data from age-matched typically developing children. Multiple acoustic variables reflecting the articulatory subsystem were different in the SMI group, compared to the NSMI and typically developing groups. A significant speech intelligibility prediction model was obtained with all variables entered into the model (adjusted R2 = .801). The articulatory subsystem showed the most substantial independent contribution (58%) to speech intelligibility. Incremental R2 analyses revealed that any single variable explained less than 9% of speech intelligibility variability. Children in the SMI group had articulatory subsystem problems as indexed by acoustic measures. As in the adult literature, the articulatory subsystem makes the primary contribution to speech intelligibility variance in dysarthria, with minimal or no contribution from other systems.

A Model of Academic Self-Concept: Perceived Difficulty and Social Comparison among Academically Accelerated Secondary School Students

ERIC Educational Resources Information Center

Wilson, Hope E.; Siegle, Del; McCoach, D. Betsy; Little, Catherine A.; Reis, Sally M.

2014-01-01

Academic self-concept predicts students' future goals and is affected by a student's relative success compared with his or her peer group. This exploratory study used structural equation modeling to examine the contributions of the perceived level of difficulty of the curriculum, in addition to the contributions of social comparison and…

Elaborations on the Socioegocentric and Dual-Level Connectionist Models of Group Interaction Processes

ERIC Educational Resources Information Center

Hewes, Dean E.

2009-01-01

The purpose of the author's contribution to this colloquy was to spark conversation on the theoretical nature of communication processes and the evidentiary requirements for testing their relationship to group outcomes. Co-discussants have raised important issues concerning the philosophical basis of the socioegocentric model (SM) and dual-level…

Interannual Variation in Phytoplankton Primary Production at a Global Scale

NASA Technical Reports Server (NTRS)

Rousseaux, Cecile Severine; Gregg, Watson W.

2013-01-01

We used the NASA Ocean Biogeochemical Model (NOBM) combined with remote sensing data via assimilation to evaluate the contribution of four phytoplankton groups to the total primary production. First, we assessed the contribution of each phytoplankton groups to the total primary production at a global scale for the period 1998-2011. Globally, diatoms contributed the most to the total phytoplankton production ((is)approximately 50%, the equivalent of 20 PgC·y1). Coccolithophores and chlorophytes each contributed approximately 20% ((is) approximately 7 PgC·y1) of the total primary production and cyanobacteria represented about 10% ((is) approximately 4 PgC·y1) of the total primary production. Primary production by diatoms was highest in the high latitudes ((is) greater than 40 deg) and in major upwelling systems (Equatorial Pacific and Benguela system). We then assessed interannual variability of this group-specific primary production over the period 1998-2011. Globally the annual relative contribution of each phytoplankton groups to the total primary production varied by maximum 4% (1-2 PgC·y1). We assessed the effects of climate variability on group-specific primary production using global (i.e., Multivariate El Niño Index, MEI) and "regional" climate indices (e.g., Southern Annular Mode (SAM), Pacific Decadal Oscillation (PDO) and North Atlantic Oscillation (NAO)). Most interannual variability occurred in the Equatorial Pacific and was associated with climate variability as indicated by significant correlation (p (is) less than 0.05) between the MEI and the group-specific primary production from all groups except coccolithophores. In the Atlantic, climate variability as indicated by NAO was significantly correlated to the primary production of 2 out of the 4 groups in the North Central Atlantic (diatoms/cyanobacteria) and in the North Atlantic (chlorophytes and coccolithophores). We found that climate variability as indicated by SAM had only a limited effect on group-specific primary production in the Southern Ocean. These results provide a modeling and data assimilation perspective to phytoplankton partitioning of primary production and contribute to our understanding of the dynamics of the carbon cycle in the oceans at a global scale.

A Model of Direct Gauge Mediation of Supersymmetry Breaking

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

Murayama, H.

1997-07-01

We present the first phenomenologically viable model of gauge meditation of supersymmetry breaking without a messenger sector or gauge singlet fields. The standard model gauge groups couple directly to the sector which breaks supersymmetry dynamically. Despite the direct coupling, it can preserve perturbative gauge unification thanks to the inverted hierarchy mechanism. There is no dangerous negative contribution to m{sup 2}{sub {tilde q}} , m{sup 2}{sub {tilde l}} due to two-loop renormalization group equation. The potentially nonuniversal supergravity contribution to m{sup 2}{sub {tilde q}} and m{sup 2}{sub {tilde l}} can be suppressed enough. The model is completely chiral, and one doesmore » not need to forbid mass terms for the messenger fields by hand. Cosmology of the model is briefly discussed. {copyright} {ital 1997} {ital The American Physical Society}« less

Contribution of organizational strategy to verbal learning and memory in adults with attention-deficit/hyperactivity disorder.

PubMed

Roth, Robert M; Wishart, Heather A; Flashman, Laura A; Riordan, Henry J; Huey, Leighton; Saykin, Andrew J

2004-01-01

Statistical mediation modeling was used to test the hypothesis that poor use of a semantic organizational strategy contributes to verbal learning and memory deficits in adults with attention-deficit/hyperactivity disorder (ADHD). Comparison of 28 adults with ADHD and 34 healthy controls revealed lower performance by the ADHD group on tests of verbal learning and memory, sustained attention, and use of semantic organization during encoding. Mediation modeling indicated that state anxiety, but not semantic organization, significantly contributed to the prediction of both learning and delayed recall in the ADHD group. The pattern of findings suggests that decreased verbal learning and memory in adult ADHD is due in part to situational anxiety and not to poor use of organizational strategies during encoding. ((c) 2004 APA, all rights reserved)

Applying a Multiple Group Causal Indicator Modeling Framework to the Reading Comprehension Skills of Third, Seventh, and Tenth Grade Students

PubMed Central

Tighe, Elizabeth L.; Wagner, Richard K.; Schatschneider, Christopher

2015-01-01

This study demonstrates the utility of applying a causal indicator modeling framework to investigate important predictors of reading comprehension in third, seventh, and tenth grade students. The results indicated that a 4-factor multiple indicator multiple indicator cause (MIMIC) model of reading comprehension provided adequate fit at each grade level. This model included latent predictor constructs of decoding, verbal reasoning, nonverbal reasoning, and working memory and accounted for a large portion of the reading comprehension variance (73% to 87%) across grade levels. Verbal reasoning contributed the most unique variance to reading comprehension at all grade levels. In addition, we fit a multiple group 4-factor MIMIC model to investigate the relative stability (or variability) of the predictor contributions to reading comprehension across development (i.e., grade levels). The results revealed that the contributions of verbal reasoning, nonverbal reasoning, and working memory to reading comprehension were stable across the three grade levels. Decoding was the only predictor that could not be constrained to be equal across grade levels. The contribution of decoding skills to reading comprehension was higher in third grade and then remained relatively stable between seventh and tenth grade. These findings illustrate the feasibility of using MIMIC models to explain individual differences in reading comprehension across the development of reading skills. PMID:25821346

A swallowtail catastrophe model for the emergence of leadership in coordination-intensive groups.

PubMed

Guastello, Stephen J; Bond, Robert W

2007-04-01

This research extended the previous studies concerning the swallowtail catastrophe model for leadership emergence to coordination-intensive groups. Thirteen 4-person groups composed of undergraduates played in Intersection coordination (card game) task and were allowed to talk while performing it; 13 other groups worked nonverbally. A questionnaire measured leadership emergence at the end of the game along with other social contributions to the groups' efforts. The swallowtail catastrophe model that was evident in previous leadership emergence phenomena in creative problem solving and production groups was found here also. All three control parameters were identified: a general participation variable that was akin to K in the rugged landscape model of self-organization, task control, and whether the groups worked verbally or nonverbally. Several new avenues for future research were delineated.

Henry's Constants of Persistent Organic Pollutants by a Group-Contribution Method Based on Scaled-Particle Theory.

PubMed

Razdan, Neil K; Koshy, David M; Prausnitz, John M

2017-11-07

A group-contribution method based on scaled-particle theory was developed to predict Henry's constants for six families of persistent organic pollutants: polychlorinated benzenes, polychlorinated biphenyls, polychlorinated dibenzodioxins, polychlorinated dibenzofurans, polychlorinated naphthalenes, and polybrominated diphenyl ethers. The group-contribution model uses limited experimental data to obtain group-interaction parameters for an easy-to-use method to predict Henry's constants for systems where reliable experimental data are scarce. By using group-interaction parameters obtained from data reduction, scaled-particle theory gives the partial molar Gibbs energy of dissolution, Δg̅ 2 , allowing calculation of Henry's constant, H 2 , for more than 700 organic pollutants. The average deviation between predicted values of log H 2 and experiment is 4%. Application of an approximate van't Hoff equation gives the temperature dependence of Henry's constants for polychlorinated biphenyls, polychlorinated naphthalenes, and polybrominated diphenyl ethers in the environmentally relevant range 0-40 °C.

A model for the generation of two-dimensional surf beat

USGS Publications Warehouse

List, Jeffrey H.

1992-01-01

A finite difference model predicting group-forced long waves in the nearshore is constructed with two interacting parts: an incident wave model providing time-varying radiation stress gradients across the nearshore, and a long-wave model which solves the equations of motion for the forcing imposed by the incident waves. Both shallow water group-bound long waves and long waves generated by a time-varying breakpoint are simulated. Model-generated time series are used to calculate the cross correlation between wave groups and long waves through the surf zone. The cross-correlation signal first observed by Tucker (1950) is well predicted. For the first time, this signal is decomposed into the contributions from the two mechanisms of leaky mode forcing. Results show that the cross-correlation signal can be explained by bound long waves which are amplified, though strongly modified, through the surf zone before reflection from the shoreline. The breakpoint-forced long waves are added to the bound long waves at a phase of pi/2 and are a secondary contribution owing to their relatively small size.

Further Insights on the Chemical Structure of Humic Substances (HS) and Chromophoric Dissolved Organic Matter (CDOM) in Relation to their Optical/Chemical Properties

NASA Astrophysics Data System (ADS)

Del Vecchio, R.; Schendorf, T. M.; Koech, K.; Blough, N. V.

2016-02-01

HS have been studied extensively over the last decades, yet the structural basis of their optical properties is still highly debated. Aromatic ketones, aldehydes and quinones along with carboxylic groups and phenolic moieties are significant constituents of HS, however their contribution to the optical properties has only recently been investigated. Chemical manipulation of selected functional groups thus represents an extremely promising approach to highlight the contribution of such groups to the HS (and CDOM) optical properties. Chemical reduction (and re-oxidation) along with pH titrations are employed herein to assess the relative contribution of aromatic ketones/aldehydes/quinones and carboxylic groups/phenolic moieties, respectively to the optical properties of HS (and CDOM). Results indicate that (a) the contribution of quinones to HS absorption and fluorescence is minor (or nil), while that of aromatic ketones (and aldehydes) is significant; (b) phenolic groups contribute more than carboxylic acids to the HS optical properties; (c) the effects of borohydride reduction and pH on the long-wavelength absorption and fluorescence is consistent with charge-transfer interactions between carbonyl and phenolic groups (as well as aromatic carboxylic acids, but to a smaller extent). Results will be presented within the context of our proposed charge-transfer model.

Analysing Recent Socioeconomic Trends in Coronary Heart Disease Mortality in England, 2000–2007: A Population Modelling Study

PubMed Central

Bajekal, Madhavi; Scholes, Shaun; Love, Hande; Hawkins, Nathaniel; O'Flaherty, Martin; Raine, Rosalind; Capewell, Simon

2012-01-01

Background Coronary heart disease (CHD) mortality in England fell by approximately 6% every year between 2000 and 2007. However, rates fell differentially between social groups with inequalities actually widening. We sought to describe the extent to which this reduction in CHD mortality was attributable to changes in either levels of risk factors or treatment uptake, both across and within socioeconomic groups. Methods and Findings A widely used and replicated epidemiological model was used to synthesise estimates stratified by age, gender, and area deprivation quintiles for the English population aged 25 and older between 2000 and 2007. Mortality rates fell, with approximately 38,000 fewer CHD deaths in 2007. The model explained about 86% (95% uncertainty interval: 65%–107%) of this mortality fall. Decreases in major cardiovascular risk factors contributed approximately 34% (21%–47%) to the overall decline in CHD mortality: ranging from about 44% (31%–61%) in the most deprived to 29% (16%–42%) in the most affluent quintile. The biggest contribution came from a substantial fall in systolic blood pressure in the population not on hypertension medication (29%; 18%–40%); more so in deprived (37%) than in affluent (25%) areas. Other risk factor contributions were relatively modest across all social groups: total cholesterol (6%), smoking (3%), and physical activity (2%). Furthermore, these benefits were partly negated by mortality increases attributable to rises in body mass index and diabetes (−9%; −17% to −3%), particularly in more deprived quintiles. Treatments accounted for approximately 52% (40%–70%) of the mortality decline, equitably distributed across all social groups. Lipid reduction (14%), chronic angina treatment (13%), and secondary prevention (11%) made the largest medical contributions. Conclusions The model suggests that approximately half the recent CHD mortality fall in England was attributable to improved treatment uptake. This benefit occurred evenly across all social groups. However, opposing trends in major risk factors meant that their net contribution amounted to just over a third of the CHD deaths averted; these also varied substantially by socioeconomic group. Powerful and equitable evidence-based population-wide policy interventions exist; these should now be urgently implemented to effectively tackle persistent inequalities. Please see later in the article for the Editors' Summary PMID:22719232

Partial molar volume of proteins studied by the three-dimensional reference interaction site model theory.

PubMed

Imai, Takashi; Kovalenko, Andriy; Hirata, Fumio

2005-04-14

The three-dimensional reference interaction site model (3D-RISM) theory is applied to the analysis of hydration effects on the partial molar volume of proteins. For the native structure of some proteins, the partial molar volume is decomposed into geometric and hydration contributions using the 3D-RISM theory combined with the geometric volume calculation. The hydration contributions are correlated with the surface properties of the protein. The thermal volume, which is the volume of voids around the protein induced by the thermal fluctuation of water molecules, is directly proportional to the accessible surface area of the protein. The interaction volume, which is the contribution of electrostatic interactions between the protein and water molecules, is apparently governed by the charged atomic groups on the protein surface. The polar atomic groups do not make any contribution to the interaction volume. The volume differences between low- and high-pressure structures of lysozyme are also analyzed by the present method.

Cultural Adaptations: Conceptual, Ethical, Contextual, and Methodological Issues for Working with Ethnocultural and Majority-World Populations.

PubMed

Bernal, Guillermo; Adames, Cristina

2017-08-01

Mayor advancements have been achieved in research on the cultural adaptation of prevention and treatment interventions that are conducted with diverse ethnocultural groups. This commentary addresses conceptual, ethical, contextual, and methodological issues related to cultural adaptations. The articles in this special issue represent a major contribution to the study of cultural adaptations in prevention science. We frame our analysis of fidelity to core intervention components using a conceptual approach that examines (a) the propositional model (theory of change), (b) the procedural model (theory of action, methods), and (c) the philosophical assumptions that undergird these models. Regarding ethics, we caution against imposing the norms, values, and world views of the Western dominant society onto vulnerable populations such as ethnocultural groups. Given that the assumption of universality in behavioral science has been questioned, and as randomized clinical trials (RCTs) seldom examine the ecological validity of evidence-based interventions and treatments (EBI/T), imposing such interventions onto ethnocultural groups is problematic since these interventions contain values, norms, beliefs, and worldviews that may be contrary to those held by many ethnocultural groups. Regarding methods, several innovative designs are discussed that serve as alternatives to the RCT and represent an important contribution to prevention science. Also, we discuss guidelines for conducting cultural adaptations. Finally, the articles in this special issue make a major contribution to the growing field of cultural adaptation of preventive interventions with ethnocultural groups and majority-world populations.

[Modeling of species distribution using topography and remote sensing data, with vascular plants of the Tukuringra Range low mountain belt (Zeya state Nature Reserve, Amur Region) as a case study].

PubMed

Dudov, S V

2016-01-01

On the basis of maximum entropy method embedded in MaxEnt software, the cartographic models are designed for spatial distribution of 63 species of vascular plants inhabiting low mountain belt of the Tukuringra Range. Initial data for modeling were actual points of a species occurrence, data on remote sensing (multispectral space snapshots by Landsat), and a digital topographic model. It is found out that the structure of factors contributing to the model is related to species ecological amplitude. The distribution of stenotopic species is determined, mainly, by the topography, which thermal and humidity conditions of habitats are associated with. To the models for eurytopic species, variables formed on the basis of remote sensing contribute significantly, those variables encompassing the parameters of the soil-vegetable cover. In course of the obtained models analyzing, three principal groups of species are revealed that have similar distribution pattern. Species of the first group are restricted in their distribution by the slopes of the. River Zeya and River Giluy gorges. Species of the second group are associated with the southern macroslope of the range and with southern slopes of large rivers' valleys. The third group incorporates those species that are distributed over the whole territory under study.

The Effect of Different Molecular Models on High School Students' Conceptions of Molecular Genetics

ERIC Educational Resources Information Center

Rotbain, Yosi; Stavy, Ruth; Marbach-Ad, Gili

2008-01-01

Our main goal in this study was to explore whether the use of models in high school molecular genetics instruction can contribute to students' understanding of concepts and processes in genetics. Three hundred and nineteen students from four comparable groups of 11th- and 12th-grade students participated. The control group (116 students) was…

Effect of Bead and Illustrations Models on High School Students' Achievement in Molecular Genetics

ERIC Educational Resources Information Center

Rotbain, Yosi; Marbach-Ad, Gili; Stavy, Ruth

2006-01-01

Our main goal in this study was to explore whether the use of models in molecular genetics instruction in high school can contribute to students' understanding of concepts and processes in genetics. Three comparable groups of 11th and 12th graders participated: The control group (116 students) was taught in the traditional lecture format, while…

Modeling Goal-Directed User Exploration in Human-Computer Interaction

DTIC Science & Technology

2011-02-01

scent, other factors including the layout position and grouping of options in the user-interface also affect user exploration and the likelihood of...grouping of options in the user-interface also affect user exploration and the likelihood of success. This dissertation contributes a new model of goal...better inform UI design. 1.1 RESEARCH GAPS IN MODELING In addition to infoscent, the layout of the UI also affects the choices made during

Interannual Variation in Phytoplankton Class-Specific Primary Production at a Global Scale

NASA Technical Reports Server (NTRS)

Rousseaux, Cecile Severine; Gregg, Watson W.

2014-01-01

We used the NASA Ocean Biogeochemical Model (NOBM) combined with remote sensing data via assimilation to evaluate the contribution of 4 phytoplankton groups to the total primary production. First we assessed the contribution of each phytoplankton groups to the total primary production at a global scale for the period 1998-2011. Globally, diatoms were the group that contributed the most to the total phytoplankton production (50, the equivalent of 20 PgC y-1. Coccolithophores and chlorophytes each contributed to 20 (7 PgC y-1 of the total primary production and cyanobacteria represented about 10 (4 PgC y(sub-1) of the total primary production. Primary production by diatoms was highest in high latitude (45) and in major upwelling systems (Equatorial Pacific and Benguela system). We then assessed interannual variability of this group-specific primary production over the period 1998-2011. Globally the annual relative contribution of each phytoplankton groups to the total primary production varied by maximum 4 (1-2 PgC y-1. We assessed the effects of climate variability on the class-specific primary production using global (i.e. Multivariate El Nio Index, MEI) and regional climate indices (e.g. Southern Annular Mode (SAM), Pacific Decadal Oscillation (PDO) and North Atlantic Oscillation (NAO)). Most interannual variability occurred in the Equatorial Pacific and was associated with climate variability as indicated by significant correlation (p 0.05) between the MEI and the class-specific primary production from all groups except coccolithophores. In the Atlantic, climate variability as indicated by NAO was significantly correlated to the primary production of 2 out of the 4 groups in the North Central Atlantic (diatomscyanobacteria) and in the North Atlantic (chlorophytes and coccolithophores). We found that climate variability as indicated by SAM had only a limited effect on the class-specific primary production in the Southern Ocean. These results provide a modeling and data assimilation perspective to phytoplankton partitioning of primary production and contribute to our understanding of the dynamics of the carbon cycle in the oceans at a global scale.

High performance HRM: NHS employee perspectives.

PubMed

Hyde, Paula; Sparrow, Paul; Boaden, Ruth; Harris, Claire

2013-01-01

The purpose of this paper is to examine National Health Service (NHS) employee perspectives of how high performance human resource (HR) practices contribute to their performance. The paper draws on an extensive qualitative study of the NHS. A novel two-part method was used; the first part used focus group data from managers to identify high-performance HR practices specific to the NHS. Employees then conducted a card-sort exercise where they were asked how or whether the practices related to each other and how each practice affected their work. In total, 11 high performance HR practices relevant to the NHS were identified. Also identified were four reactions to a range of HR practices, which the authors developed into a typology according to anticipated beneficiaries (personal gain, organisation gain, both gain and no-one gains). Employees were able to form their own patterns (mental models) of performance contribution for a range of HR practices (60 interviewees produced 91 groupings). These groupings indicated three bundles particular to the NHS (professional development, employee contribution and NHS deal). These mental models indicate employee perceptions about how health services are organised and delivered in the NHS and illustrate the extant mental models of health care workers. As health services are rearranged and financial pressures begin to bite, these mental models will affect employee reactions to changes both positively and negatively. The novel method allows for identification of mental models that explain how NHS workers understand service delivery. It also delineates the complex and varied relationships between HR practices and individual performance.

Multi-Model Comparison of Lateral Boundary Contributions to ...

EPA Pesticide Factsheets

As the National Ambient Air Quality Standards (NAAQS) for ozone become more stringent, there has been growing attention on characterizing the contributions and the uncertainties in ozone from outside the US to the ozone concentrations within the US. The third phase of the Air Quality Model Evaluation International Initiative (AQMEII3) provides an opportunity to investigate this issue through the combined efforts of multiple research groups in the US and Europe. The model results cover a range of representations of chemical and physical processes, vertical and horizontal resolutions, and meteorological fields to drive the regional chemical transport models (CTMs), all of which are important components of model uncertainty (Solazzo and Galmarini, 2016). In AQMEII3, all groups were asked to track the contribution of ozone from lateral boundary through the use of chemically inert tracers. Though the inert tracer method tends to overestimate the impact of ozone boundary conditions compared with other methods such as chemically reactive tracers and source apportionment (Baker et al., 2015), the method takes the least effort to implement in different models, and is thus useful in highlighting and understanding the process-level differences amongst the models. In this study, results from four models were included (CMAQ driven by WRF, CAMx driven by WRF, CMAQ driven by CCLM, DEHM driven by WRF). At each site, the distribution of daily maximum 8-hour ozone, and the corre

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

Ünlü, Hilmi, E-mail: hunlu@itu.edu.tr

We propose a non-orthogonal sp{sup 3} hybrid bond orbital model to determine the electronic properties of semiconductor heterostructures. The model considers the non-orthogonality of sp{sup 3} hybrid states of nearest neighboring adjacent atoms using the intra-atomic Coulomb interactions corrected Hartree-Fock atomic energies and metallic contribution to calculate the valence band width energies of group IV elemental and group III-V and II-VI compound semiconductors without any adjustable parameter.

Thermodynamic Modeling of Organic-Inorganic Aerosols with the Group-Contribution Model AIOMFAC

NASA Astrophysics Data System (ADS)

Zuend, A.; Marcolli, C.; Luo, B. P.; Peter, T.

2009-04-01

Liquid aerosol particles are - from a physicochemical viewpoint - mixtures of inorganic salts, acids, water and a large variety of organic compounds (Rogge et al., 1993; Zhang et al., 2007). Molecular interactions between these aerosol components lead to deviations from ideal thermodynamic behavior. Strong non-ideality between organics and dissolved ions may influence the aerosol phases at equilibrium by means of liquid-liquid phase separations into a mainly polar (aqueous) and a less polar (organic) phase. A number of activity models exists to successfully describe the thermodynamic equilibrium of aqueous electrolyte solutions. However, the large number of different, often multi-functional, organic compounds in mixed organic-inorganic particles is a challenging problem for the development of thermodynamic models. The group-contribution concept as introduced in the UNIFAC model by Fredenslund et al. (1975), is a practical method to handle this difficulty and to add a certain predictability for unknown organic substances. We present the group-contribution model AIOMFAC (Aerosol Inorganic-Organic Mixtures Functional groups Activity Coefficients), which explicitly accounts for molecular interactions between solution constituents, both organic and inorganic, to calculate activities, chemical potentials and the total Gibbs energy of mixed systems (Zuend et al., 2008). This model enables the computation of vapor-liquid (VLE), liquid-liquid (LLE) and solid-liquid (SLE) equilibria within one framework. Focusing on atmospheric applications we considered eight different cations, five anions and a wide range of alcohols/polyols as organic compounds. With AIOMFAC, the activities of the components within an aqueous electrolyte solution are very well represented up to high ionic strength. We show that the semi-empirical middle-range parametrization of direct organic-inorganic interactions in alcohol-water-salt solutions enables accurate computations of vapor-liquid and liquid-liquid equilibria. References Fredenslund, A., Jones, R. L., and Prausnitz, J. M.: Group-Contribution Estimation of Activity Coefficients in Nonideal Liquid Mixtures, AIChE J., 21, 1086-1099, 1975. Rogge, W. F., Mazurek, M. A., Hildemann, L. M., Cass, G. R., and Simoneit, B. R. T.: Quantification of Urban Organic Aerosols at a Molecular Level: Identification, Abundance and Seasonal Variation, Atmos. Environ., 27, 1309-1330, 1993. Zhang, Q. et al.: Ubiquity and dominance of oxygenated species in organic aerosols in anthropogenically influenced Northern Hemisphere midlatitudes, Geophys. Res. Lett., 34, L13 801, 2007. Zuend, A., Marcolli, C., Luo, B. P., and Peter, T.: A thermodynamic model of mixed organic-inorganic aerosols to predict activity coefficients, Atmos. Chem. Phys., 8, 4559-4593, 2008.

Predicting Speech Intelligibility with A Multiple Speech Subsystems Approach in Children with Cerebral Palsy

PubMed Central

Lee, Jimin; Hustad, Katherine C.; Weismer, Gary

2014-01-01

Purpose Speech acoustic characteristics of children with cerebral palsy (CP) were examined with a multiple speech subsystem approach; speech intelligibility was evaluated using a prediction model in which acoustic measures were selected to represent three speech subsystems. Method Nine acoustic variables reflecting different subsystems, and speech intelligibility, were measured in 22 children with CP. These children included 13 with a clinical diagnosis of dysarthria (SMI), and nine judged to be free of dysarthria (NSMI). Data from children with CP were compared to data from age-matched typically developing children (TD). Results Multiple acoustic variables reflecting the articulatory subsystem were different in the SMI group, compared to the NSMI and TD groups. A significant speech intelligibility prediction model was obtained with all variables entered into the model (Adjusted R-squared = .801). The articulatory subsystem showed the most substantial independent contribution (58%) to speech intelligibility. Incremental R-squared analyses revealed that any single variable explained less than 9% of speech intelligibility variability. Conclusions Children in the SMI group have articulatory subsystem problems as indexed by acoustic measures. As in the adult literature, the articulatory subsystem makes the primary contribution to speech intelligibility variance in dysarthria, with minimal or no contribution from other systems. PMID:24824584

Learning with Artificial Worlds: Computer-Based Modelling in the Curriculum.

ERIC Educational Resources Information Center

Mellar, Harvey, Ed.; And Others

With the advent of the British National Curriculum, computer-based modeling has become an integral part of the school curriculum. This book is about modeling in education and providing children with computer tools to create and explore representations of the world. Members of the London Mental Models Group contributed their research: (1)…

Including non-dietary sources into an exposure assessment of the European Food Safety Authority: The challenge of multi-sector chemicals such as Bisphenol A.

PubMed

von Goetz, N; Pirow, R; Hart, A; Bradley, E; Poças, F; Arcella, D; Lillegard, I T L; Simoneau, C; van Engelen, J; Husoy, T; Theobald, A; Leclercq, C

2017-04-01

In the most recent risk assessment for Bisphenol A for the first time a multi-route aggregate exposure assessment was conducted by the European Food Safety Authority. This assessment includes exposure via dietary sources, and also contributions of the most important non-dietary sources. Both average and high aggregate exposure were calculated by source-to-dose modeling (forward calculation) for different age groups and compared with estimates based on urinary biomonitoring data (backward calculation). The aggregate exposure estimates obtained by forward and backward modeling are in the same order of magnitude, with forward modeling yielding higher estimates associated with larger uncertainty. Yet, only forward modeling can indicate the relative contribution of different sources. Dietary exposure, especially via canned food, appears to be the most important exposure source and, based on the central aggregate exposure estimates, contributes around 90% to internal exposure to total (conjugated plus unconjugated) BPA. Dermal exposure via thermal paper and to a lesser extent via cosmetic products may contribute around 10% for some age groups. The uncertainty around these estimates is considerable, but since after dermal absorption a first-pass metabolism of BPA by conjugation is lacking, dermal sources may be of equal or even higher toxicological relevance than dietary sources. Copyright © 2017 Elsevier Inc. All rights reserved.

Contribution of hydrophobic effect to the sorption of phenanthrene, 9-phenanthrol and 9, 10-phenanthrenequinone on carbon nanotubes.

PubMed

Peng, Hongbo; Zhang, Di; Pan, Bo; Peng, Jinhui

2017-02-01

Polycyclic aromatic hydrocarbons (PAHs), with diverse sources and acute toxicity, are categorized as priority pollutants. Previous studies have stated that the hydrophobic effect controls PAH sorption, but no study has been conducted to quantify the exact contribution of the hydrophobic effect. Considering the well-defined structure of carbon nanotubes and their stable chemical composition in organic solvents, three multi-walled carbon nanotubes (MWCNTs) were selected as a model adsorbent. Phenanthrene (PHE) and its degradation intermediates 9-phenanthrol (PTR) and 9, 10-phenanthrenequinone (PQN) were used as model adsorbates. To quantify the contribution of the hydrophobic effect for these three chemicals, the effect of organic solvent (methanol and hexadecane) was investigated. Adsorption isotherms for PHE, PTR and PQN were well fitted by the Freundlich isotherm model. A positive relationship between adsorption affinities of these three chemicals and specific surface area (SSA) was observed in hexadecane but not in water or methanol. Other factors should be included other than SSA. Adsorption of PQN on MWCNTs with oxygen functional groups was higher than that on pristine MWCNTs due to π-π EDA interactions. The contribution of hydrophobic effect was 50%-85% for PHE, suggesting that hydrophobic effect was the predominant mechanism. This contribution was lower than 30% for PTR/PQN on functionalized MWCNTs. Hydrogen bonds control the adsorption of PTR, and π-π bonding interactions control PQN sorption after screening out the hydrophobic effect in hexadecane. Hydrophobic effect is the control mechanism for nonpolar chemicals, while functional groups of CNTs and solvent types control the adsorption of polar compounds. Extended work on quantifying the relationship between chemical structure and the contribution of the hydrophobic effect will provide a useful technique for PAH fate modeling. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Dual-Factor Model of Mental Health: Further Study of the Determinants of Group Differences

ERIC Educational Resources Information Center

Lyons, Michael D.; Huebner, E. Scott; Hills, Kimberly J.; Shinkareva, Svetlana V.

2012-01-01

Consistent with a positive psychology framework, this study examined the contributions of personality, environmental, and perceived social support variables in classifying adolescents using Greenspoon and Saklofske's Dual-Factor model of mental health. This model incorporates information about positive subjective well-being (SWB), along with…

Job Design for Learning in Work Groups

ERIC Educational Resources Information Center

Lantz, Annika; Brav, Agneta

2007-01-01

Purpose--What is required of job design and production planning, if they are to result in a work group taking a self-starting approach and going beyond what is formally required of it? This paper aims to contribute to group research by testing a theoretical model of relations between job design on the one hand (captured as completeness, demand on…

Study of the slope of the linear relationship between retention and mobile phase composition (Snyder-Soczewiñski model) in normal phase liquid chromatography with bonded and charge-transfer phases.

PubMed

Wu, Di; Lucy, Charles A

2016-12-02

The Snyder model and the Soczewiñski model are compared on classic NPLC bonded phases using literature data, and on the charge transfer 2, 4-dinitroanilinopropyl (DNAP) column using experimentally collected data. Overall, the Snyder model slightly better predicts the n-slope than the Soczewiñski model. However, both models give comparable uncertainty in predicting n-slope for a given compound. The number of aromatic double bonds was the most suitable descriptor for estimating the relative n-slope of PAHs, as it correlated with behavior better than the number of aromatic rings and is simpler to calculate than the solute adsorption area. On the DNAP phase, a modified Soczewiñski model is suggested to allow for the significant contribution of the aromatic rings to the n-slope. For classic NPLC bonded phases and DNAP columns, the contribution of polar group to the n-slope parallels the adsorption energy of each polar group. Copyright © 2016 Elsevier B.V. All rights reserved.

Surface vibrational structure at alkane liquid/vapor interfaces

NASA Astrophysics Data System (ADS)

Esenturk, Okan; Walker, Robert A.

2006-11-01

Broadband vibrational sum frequency spectroscopy (VSFS) has been used to examine the surface structure of alkane liquid/vapor interfaces. The alkanes range in length from n-nonane (C9H20) to n-heptadecane (C17H36), and all liquids except heptadecane are studied at temperatures well above their bulk (and surface) freezing temperatures. Intensities of vibrational bands in the CH stretching region acquired under different polarization conditions show systematic, chain length dependent changes. Data provide clear evidence of methyl group segregation at the liquid/vapor interface, but two different models of alkane chain structure can predict chain length dependent changes in band intensities. Each model leads to a different interpretation of the extent to which different chain segments contribute to the anisotropic interfacial region. One model postulates that changes in vibrational band intensities arise solely from a reduced surface coverage of methyl groups as alkane chain length increases. The additional methylene groups at the surface must be randomly distributed and make no net contribution to the observed VSF spectra. The second model considers a simple statistical distribution of methyl and methylene groups populating a three dimensional, interfacial lattice. This statistical picture implies that the VSF signal arises from a region extending several functional groups into the bulk liquid, and that the growing fraction of methylene groups in longer chain alkanes bears responsibility for the observed spectral changes. The data and resulting interpretations provide clear benchmarks for emerging theories of molecular structure and organization at liquid surfaces, especially for liquids lacking strong polar ordering.

Prediction of User Preference over Shared Control Paradigms for a Robotic Wheelchair

DTIC Science & Technology

2017-07-20

the experimentally -observed changes between subject groups and sessions, while providing unique insight into the relative contribution of task metrics...WHEELCHAIR, including the four tested shared- control paradigms. The correlation model and experimental results are provided in Sections IV and V. Section VI...paradigm-specific models. Moreover, we also observe differences between sub- ject groups —meaning that subjects’ evaluations of a control paradigm are

Cognitive Correlates of Inadequate Response to Reading Intervention

PubMed Central

Fletcher, Jack M.; Stuebing, Karla K.; Barth, Amy E.; Denton, Carolyn A.; Cirino, Paul T.; Francis, David J.; Vaughn, Sharon

2012-01-01

The cognitive attributes of Grade 1 students who responded adequately and inadequately to a Tier 2 reading intervention were evaluated. The groups included inadequate responders based on decoding and fluency criteria (n = 29), only fluency criteria (n = 75), adequate responders (n = 85), and typically achieving students (n = 69). The cognitive measures included assessments of phonological awareness, rapid letter naming, oral language skills, processing speed, vocabulary, and nonverbal problem solving. Comparisons of all four groups identified phonological awareness as the most significant contributor to group differentiation. Measures of rapid letter naming, syntactic comprehension/working memory, and vocabulary also contributed uniquely to some comparisons of adequate and inadequate responders. In a series of regression analyses designed to evaluate the contributions of responder status to cognitive skills independently of variability in reading skills, only the model for rapid letter naming achieved statistical significance, accounting for a small (1%) increment in explained variance beyond that explained by models based only on reading levels. Altogether, these results do not suggest qualitative differences among the groups, but are consistent with a continuum of severity associated with the level of reading skills across the four groups. PMID:23125475

From quantum affine groups to the exact dynamical correlation function of the Heisenberg model

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

Bougourzi, A.H.; Couture, M.; Kacir, M.

1997-01-20

The exact form factors of the Heisenberg models XXX and XXZ have been recently computed through the quantum affine symmetry of XXZ model in the thermodynamic limit. The authors use them to derive an exact formula for the contribution of two spinons to the dynamical correlation function of XXX model at zero temperature.

A group contribution method for associating chain molecules based on the statistical associating fluid theory (SAFT-γ)

NASA Astrophysics Data System (ADS)

Lymperiadis, Alexandros; Adjiman, Claire S.; Galindo, Amparo; Jackson, George

2007-12-01

A predictive group-contribution statistical associating fluid theory (SAFT-γ) is developed by extending the molecular-based SAFT-VR equation of state [A. Gil-Villegas et al. J. Chem. Phys. 106, 4168 (1997)] to treat heteronuclear molecules which are formed from fused segments of different types. Our models are thus a heteronuclear generalization of the standard models used within SAFT, comparable to the optimized potentials for the liquid state OPLS models commonly used in molecular simulation; an advantage of our SAFT-γ over simulation is that an algebraic description for the thermodynamic properties of the model molecules can be developed. In our SAFT-γ approach, each functional group in the molecule is modeled as a united-atom spherical (square-well) segment. The different groups are thus characterized by size (diameter), energy (well depth) and range parameters representing the dispersive interaction, and by shape factor parameters (which denote the extent to which each group contributes to the overall molecular properties). For associating groups a number of bonding sites are included on the segment: in this case the site types, the number of sites of each type, and the appropriate association energy and range parameters also have to be specified. A number of chemical families (n-alkanes, branched alkanes, n-alkylbenzenes, mono- and diunsaturated hydrocarbons, and n-alkan-1-ols) are treated in order to assess the quality of the SAFT-γ description of the vapor-liquid equilibria and to estimate the parameters of various functional groups. The group parameters for the functional groups present in these compounds (CH3, CH2, CH3CH, ACH, ACCH2, CH2, CH , and OH) together with the unlike energy parameters between groups of different types are obtained from an optimal description of the pure component phase equilibria. The approach is found to describe accurately the vapor-liquid equilibria with an overall %AAD of 3.60% for the vapor pressure and 0.86% for the saturated liquid density. The fluid phase equilibria of some larger compounds comprising these groups, which are not included in the optimization database and some binary mixtures are examined to confirm the predictive capability of the SAFT-γ approach. A key advantage of our method is that the binary interaction parameters between groups can be estimated directly from an examination of pure components alone. This means that as a first approximation the fluid-phase equilibria of mixtures of compounds comprising the groups considered can be predicted without the need for any adjustment of the binary interaction parameters (which is common in other approaches). The special case of molecular models comprising tangentially bonded (all-atom and united-atom) segments is considered separately; we comment on the adequacy of such models in representing the properties of real molecules.

A group contribution method for associating chain molecules based on the statistical associating fluid theory (SAFT-gamma).

PubMed

Lymperiadis, Alexandros; Adjiman, Claire S; Galindo, Amparo; Jackson, George

2007-12-21

A predictive group-contribution statistical associating fluid theory (SAFT-gamma) is developed by extending the molecular-based SAFT-VR equation of state [A. Gil-Villegas et al. J. Chem. Phys. 106, 4168 (1997)] to treat heteronuclear molecules which are formed from fused segments of different types. Our models are thus a heteronuclear generalization of the standard models used within SAFT, comparable to the optimized potentials for the liquid state OPLS models commonly used in molecular simulation; an advantage of our SAFT-gamma over simulation is that an algebraic description for the thermodynamic properties of the model molecules can be developed. In our SAFT-gamma approach, each functional group in the molecule is modeled as a united-atom spherical (square-well) segment. The different groups are thus characterized by size (diameter), energy (well depth) and range parameters representing the dispersive interaction, and by shape factor parameters (which denote the extent to which each group contributes to the overall molecular properties). For associating groups a number of bonding sites are included on the segment: in this case the site types, the number of sites of each type, and the appropriate association energy and range parameters also have to be specified. A number of chemical families (n-alkanes, branched alkanes, n-alkylbenzenes, mono- and diunsaturated hydrocarbons, and n-alkan-1-ols) are treated in order to assess the quality of the SAFT-gamma description of the vapor-liquid equilibria and to estimate the parameters of various functional groups. The group parameters for the functional groups present in these compounds (CH(3), CH(2), CH(3)CH, ACH, ACCH(2), CH(2)=, CH=, and OH) together with the unlike energy parameters between groups of different types are obtained from an optimal description of the pure component phase equilibria. The approach is found to describe accurately the vapor-liquid equilibria with an overall %AAD of 3.60% for the vapor pressure and 0.86% for the saturated liquid density. The fluid phase equilibria of some larger compounds comprising these groups, which are not included in the optimization database and some binary mixtures are examined to confirm the predictive capability of the SAFT-gamma approach. A key advantage of our method is that the binary interaction parameters between groups can be estimated directly from an examination of pure components alone. This means that as a first approximation the fluid-phase equilibria of mixtures of compounds comprising the groups considered can be predicted without the need for any adjustment of the binary interaction parameters (which is common in other approaches). The special case of molecular models comprising tangentially bonded (all-atom and united-atom) segments is considered separately; we comment on the adequacy of such models in representing the properties of real molecules.

Group Membership, Group Change, and Intergroup Attitudes: A Recategorization Model Based on Cognitive Consistency Principles.

PubMed

Roth, Jenny; Steffens, Melanie C; Vignoles, Vivian L

2018-01-01

The present article introduces a model based on cognitive consistency principles to predict how new identities become integrated into the self-concept, with consequences for intergroup attitudes. The model specifies four concepts (self-concept, stereotypes, identification, and group compatibility) as associative connections. The model builds on two cognitive principles, balance-congruity and imbalance-dissonance, to predict identification with social groups that people currently belong to, belonged to in the past, or newly belong to. More precisely, the model suggests that the relative strength of self-group associations (i.e., identification) depends in part on the (in)compatibility of the different social groups. Combining insights into cognitive representation of knowledge, intergroup bias, and explicit/implicit attitude change, we further derive predictions for intergroup attitudes. We suggest that intergroup attitudes alter depending on the relative associative strength between the social groups and the self, which in turn is determined by the (in)compatibility between social groups. This model unifies existing models on the integration of social identities into the self-concept by suggesting that basic cognitive mechanisms play an important role in facilitating or hindering identity integration and thus contribute to reducing or increasing intergroup bias.

Group Membership, Group Change, and Intergroup Attitudes: A Recategorization Model Based on Cognitive Consistency Principles

PubMed Central

Roth, Jenny; Steffens, Melanie C.; Vignoles, Vivian L.

2018-01-01

The present article introduces a model based on cognitive consistency principles to predict how new identities become integrated into the self-concept, with consequences for intergroup attitudes. The model specifies four concepts (self-concept, stereotypes, identification, and group compatibility) as associative connections. The model builds on two cognitive principles, balance–congruity and imbalance–dissonance, to predict identification with social groups that people currently belong to, belonged to in the past, or newly belong to. More precisely, the model suggests that the relative strength of self-group associations (i.e., identification) depends in part on the (in)compatibility of the different social groups. Combining insights into cognitive representation of knowledge, intergroup bias, and explicit/implicit attitude change, we further derive predictions for intergroup attitudes. We suggest that intergroup attitudes alter depending on the relative associative strength between the social groups and the self, which in turn is determined by the (in)compatibility between social groups. This model unifies existing models on the integration of social identities into the self-concept by suggesting that basic cognitive mechanisms play an important role in facilitating or hindering identity integration and thus contribute to reducing or increasing intergroup bias. PMID:29681878

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

Butler, W.J.; Kalasinski, L.A.

In this paper, a generalized logistic regression model for correlated observations is used to analyze epidemiologic data on the frequency of spontaneous abortion among a group of women office workers. The results are compared to those obtained from the use of the standard logistic regression model that assumes statistical independence among all the pregnancies contributed by one woman. In this example, the correlation among pregnancies from the same woman is fairly small and did not have a substantial impact on the magnitude of estimates of parameters of the model. This is due at least partly to the small average numbermore » of pregnancies contributed by each woman.« less

Modeling Homophily over Time with an Actor-Partner Interdependence Model

ERIC Educational Resources Information Center

Popp, Danielle; Laursen, Brett; Kerr, Margaret; Stattin, Hakan; Burk, William J.

2008-01-01

Selection and socialization have been implicated in friendship homophily, but the relative contributions of each are difficult to measure simultaneously because of the nonindependent nature of the data. To address this problem, the authors applied a multiple-groups longitudinal actor-partner interdependence model (D. A. Kashy & D. A. Kenny,…

Cultivating Self-Awareness in Counselors-in-Training through Group Supervision

ERIC Educational Resources Information Center

Del Moro, Ronald R.

2012-01-01

This study investigated processes, strategies, and frameworks that took place during group supervision classes, which best cultivate the self-awareness of Mental Health and Marriage and Family Counselors-in-Training (CITs). It was designed to explore factors across multiple theoretical models, which contributed to the cultivation of self-awareness…

A Qualitative Study on the Contribution of Educational Administrators' Use of Social Media to Educational Administration

ERIC Educational Resources Information Center

Bayram, Arslan

2017-01-01

The phenomenology design which is one of the qualitative research methods was employed in this research that aimed to reveal the contribution of educational administrators' usage of social media to educational administration. The research is an explanatory study survey model. The study groups were selected using convenience sampling method.…

Productive work groups in complex hospital units. Proposed contributions of the nurse executive.

PubMed

Sheafor, M

1991-05-01

The Fiedler and Garcia cognitive resources contingency model of leadership offers a new approach for nurse executives to influence the productivity of work groups led by nurse managers. The author offers recommendations toward achieving the relatively stress-free environment for nurse managers specified by the model using Schmeiding's application of Orlando's communication theory to nursing administration. Suggestions for incorporating these insights into graduate education for nursing administration follow.

Ecological Models of Sexual Satisfaction among Lesbian/Bisexual and Heterosexual Women

PubMed Central

Henderson, Alison W.; Simoni, Jane M.

2014-01-01

Sexual satisfaction is an integral component of sexual health and well-being, yet we know little about which factors contribute to it among lesbian/bisexual women. To examine a proposed ecological model of sexual satisfaction, we conducted an internet survey of married heterosexual women and lesbian/bisexual women in committed same-sex relationships. Structural equation modeling included five final latent variables for heterosexual women and seven final latent variables for lesbian/bisexual women. Overall, results indicated that, for both groups of women, a similar constellation of factors (depressive symptoms, relationship satisfaction, sexual functioning, and social support) was related to sexual satisfaction. In lesbian/bisexual women, internalized homophobia was an additional factor. Contrary to expectations, the presence of children in the home and a history of childhood sexual abuse did not contribute significantly to the model for either group. Findings support the idea that gender socialization may influence sexual satisfaction more than socialization around sexual orientation. Additionally, given that for both groups of women relationship satisfaction explained a substantial amount of variance in sexual satisfaction, sexual concerns may be better addressed at the relationship than the individual level. PMID:18574685

Career Theory from an International Perspective

ERIC Educational Resources Information Center

Guichard, Jean; Lenz, Janet

2005-01-01

The Career Theory in an International Perspective group highlighted 7 approaches: action theory, self-construction model, transition model, dynamics of entering the workforce, narrative in career guidance, dilemma approach, and interactive identity construction. Three main characteristics appear to be common to these different contributions: (a)…

Interannual Variation in Phytoplankton Class-specific Primary Production at a Global Scale

NASA Technical Reports Server (NTRS)

Rousseaux, Cecile; Gregg, Watson

2014-01-01

Phytoplankton is responsible for over half of the net primary production on earth. The knowledge on the contribution of various phytoplankton groups to the total primary production is still poorly understood. Data from satellite observations suggest that for upwelling regions, photosynthetic rates by microplankton is higher than that of nanoplankton but that when the spatial extent is considered, the production by nanoplankton is comparable or even larger than microplankton. Here, we used the NASA Ocean Biogeochemical Model (NOBM) combined with remote sensing data via assimilation to evaluate the contribution of 4 phytoplankton groups to the total primary production. Globally, diatoms were the group that contributed the most to the total phytoplankton production (approx. 50%) followed by coccolithophores and chlorophytes. Primary production by diatoms was highest in high latitude (>45 deg) and in major upwelling systems (Equatorial Pacific and Benguela system). We assessed the effects of climate variability on the class-specific primary production using global (i.e. Multivariate El Nino Index, MEI) and 'regional' climate indices (e.g. Southern Annular Mode (SAM), Pacific Decadal Oscillation (PDO) and North Atlantic Oscillation (NAO)). Most interannual variability occurred in the Equatorial Pacific and was associated with climate variability. These results provide a modeling and data assimilation perspective to phytoplankton partitioning of primary production and contribute to our understanding of the dynamics of the carbon cycle in the oceans at a global scale.

Estimating statistical power for open-enrollment group treatment trials.

PubMed

Morgan-Lopez, Antonio A; Saavedra, Lissette M; Hien, Denise A; Fals-Stewart, William

2011-01-01

Modeling turnover in group membership has been identified as a key barrier contributing to a disconnect between the manner in which behavioral treatment is conducted (open-enrollment groups) and the designs of substance abuse treatment trials (closed-enrollment groups, individual therapy). Latent class pattern mixture models (LCPMMs) are emerging tools for modeling data from open-enrollment groups with membership turnover in recently proposed treatment trials. The current article illustrates an approach to conducting power analyses for open-enrollment designs based on the Monte Carlo simulation of LCPMM models using parameters derived from published data from a randomized controlled trial comparing Seeking Safety to a Community Care condition for women presenting with comorbid posttraumatic stress disorder and substance use disorders. The example addresses discrepancies between the analysis framework assumed in power analyses of many recently proposed open-enrollment trials and the proposed use of LCPMM for data analysis. Copyright © 2011 Elsevier Inc. All rights reserved.

Soil Fluxomics: Disentangling Microbial Group Specific Metabolism by Modeling of 13C-Incorporation into PLFAs

NASA Astrophysics Data System (ADS)

Apostel, C.; Kuzyakov, Y.; Dippold, M. A.

2016-12-01

Soils are the largest terrestrial C sinks and microorganisms are the most important drivers of organic matter (OM) dynamics in soils: C allocation to ana- or catabolism in microbial cells is the decisive step, whether C gets oxidized to CO2 or whether it is allocated to microbial biomass, which, after cell death can be stabilized in soils. The metabolic parameter describing the ratio between the two fluxes is the carbon use efficiency (CUE), which can be assessed by position-specific labeling followed by metabolic flux modelling. However, to disentangle the single microbial groups' contribution to the bulk soil CUE, a tracing of individual groups metabolism is necessary. We assessed short-term (3 and 10 days) transformations of monosaccharides by adding position-specifically 13C labeled glucose to soil in a field experiment. Incorporation of 13C in the microbial PLFAs enabled us to distinguish individual microbial groups metabolic fluxes and compare their C-utilization efficiency using a quantitative C-flux model. The position-specific pattern in PLFAs revealed two sets of microorganisms: one metabolized glucose mainly by glycolysis and the other mainly by the pentose-phosphate pathway, which results in a higher CUE. Both of those sets included prokaryotic as well as eukaryotic microorganisms. This demonstrates that phylogenetic grouping is not decisive for the metabolic behavior of a microbial group and that the contribution of individual group members to the soil C fluxes cannot be concluded from their phylogeny.

Real payoffs and virtual trading in agent based market models

NASA Astrophysics Data System (ADS)

Ferreira, Fernando F.; Marsili, Matteo

2005-01-01

The -Game was recently introduced as an extension of the Minority Game. In this paper we compare this model with the well know Minority Game and the Majority Game models. Due to the inter-temporal nature of the market payoff, we introduce a two step transaction with single and mixed group of interacting traders. When the population is composed of two different group of -traders, they show an anti-imitative behavior. However, when they interact with minority or majority players the $-population imitates the usual behavior of these players. Finally we discuss how these models contribute to clarify the market mechanism.

Mechanisms used to increase peak propulsive force following 12-weeks of gait training in individuals poststroke.

PubMed

Hsiao, HaoYuan; Knarr, Brian A; Pohlig, Ryan T; Higginson, Jill S; Binder-Macleod, Stuart A

2016-02-08

Current rehabilitation efforts for individuals poststroke focus on increasing walking speed because it is a predictor of community ambulation and participation. Greater propulsive force is required to increase walking speed. Previous studies have identified that trailing limb angle (TLA) and ankle moment are key factors to increases in propulsive force during gait. However, no studies have determined the relative contribution of these two factors to increase propulsive force following intervention. The purpose of this study was to quantify the relative contribution of ankle moment and TLA to increases in propulsive force following 12-weeks of gait training for individuals poststroke. Forty-five participants were assigned to 1 of 3 training groups: training at self-selected speeds (SS), at fastest comfortable speeds (Fast), and Fast with functional electrical stimulation (FastFES). For participants who gained paretic propulsive force following training, a biomechanical-based model previously developed for individuals poststroke was used to calculate the relative contributions of ankle moment and TLA. A two-way, mixed-model design, analysis of covariance adjusted for baseline walking speed was performed to analyze changes in TLA and ankle moment across groups. The model showed that TLA was the major contributor to increases in propulsive force following training. Although the paretic TLA increased from pre-training to post-training, no differences were observed between groups. In contrast, increases in paretic ankle moment were observed only in the FastFES group. Our findings suggested that specific targeting may be needed to increase ankle moment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Mechanisms used to increase peak propulsive force following 12-weeks of gait training in individuals poststroke

PubMed Central

Hsiao, HaoYuan; Knarr, Brian A.; Pohlig, Ryan T.; Higginson, Jill S.; Binder-Macleod, Stuart A.

2016-01-01

Current rehabilitation efforts for individuals poststroke focus on increasing walking speed because it is a predictor of community ambulation and participation. Greater propulsive force is required to increase walking speed. Previous studies have identified that trailing limb angle (TLA) and ankle moment are key factors to increases in propulsive force during gait. However, no studies have determined the relative contribution of these two factors to increase propulsive force following intervention. The purpose of this study was to quantify the relative contribution of ankle moment and TLA to increases in propulsive force following 12-weeks of gait training for individuals poststroke. Forty-five participants were assigned to 1 of 3 training groups: training at self-selected speeds (SS), at fastest comfortable speeds (Fast), and Fast with functional electrical stimulation (FastFES). For participants who gained paretic propulsive force following training, a biomechanical-based model previously developed for individuals poststroke was used to calculate the relative contributions of ankle moment and TLA. A two-way, mixed-model design, analysis of covariance adjusted for baseline walking speed was performed to analyze changes in TLA and ankle moment across groups. The model showed that TLA was the major contributor to increases in propulsive force following training. Although the paretic TLA increased from pre-training to post-training, no differences were observed between groups. In contrast, increases in paretic ankle moment were observed only in the FastFES group. Our findings suggested that specific targeting may be needed to increase ankle moment. PMID:26776931

Hygroscopicity of organic compounds as a function of carbon chain length, carboxyl, hydroperoxy, and carbonyl functional groups

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

Petters, Sarah Suda; Pagonis, Demetrios; Claflin, Megan Suzanne

The albedo and microphysical properties of clouds are controlled in part by the hygroscopicity of particles serving as cloud condensation nuclei (CCN). Hygroscopicity of complex organic mixtures in the atmosphere varies widely and remains challenging to predict. Here we present new measurements characterizing the CCN activity of pure compounds in which carbon chain length and the number of hydroperoxy, carboxyl, and carbonyl functional groups were systematically varied to establish the contributions of these groups to organic aerosol apparent hygroscopicity. Apparent hygroscopicity decreased with carbon chain length and increased with polar functional groups in the order carboxyl > hydroperoxy > carbonyl.more » Activation diameters at different supersaturations deviated from the -3/2 slope in log-log space predicted by Köhler theory, suggesting that water solubility limits CCN activity of particles composed of weakly functionalized organic compounds. Results are compared to a functional group contribution model that predicts CCN activity of organic compounds. The model performed well for most compounds but under-predicted the CCN activity of hydroperoxy groups. New best-fit hydroperoxy group/water interaction parameters were derived from the available CCN data. Lastly, these results may help improve estimates of the CCN activity of ambient organic aerosols from composition data.« less

Hygroscopicity of organic compounds as a function of carbon chain length, carboxyl, hydroperoxy, and carbonyl functional groups

DOE PAGES

Petters, Sarah Suda; Pagonis, Demetrios; Claflin, Megan Suzanne; ...

2017-06-16

The albedo and microphysical properties of clouds are controlled in part by the hygroscopicity of particles serving as cloud condensation nuclei (CCN). Hygroscopicity of complex organic mixtures in the atmosphere varies widely and remains challenging to predict. Here we present new measurements characterizing the CCN activity of pure compounds in which carbon chain length and the number of hydroperoxy, carboxyl, and carbonyl functional groups were systematically varied to establish the contributions of these groups to organic aerosol apparent hygroscopicity. Apparent hygroscopicity decreased with carbon chain length and increased with polar functional groups in the order carboxyl > hydroperoxy > carbonyl.more » Activation diameters at different supersaturations deviated from the -3/2 slope in log-log space predicted by Köhler theory, suggesting that water solubility limits CCN activity of particles composed of weakly functionalized organic compounds. Results are compared to a functional group contribution model that predicts CCN activity of organic compounds. The model performed well for most compounds but under-predicted the CCN activity of hydroperoxy groups. New best-fit hydroperoxy group/water interaction parameters were derived from the available CCN data. Lastly, these results may help improve estimates of the CCN activity of ambient organic aerosols from composition data.« less

On Valuing Peers: Theories of Learning and Intercultural Competence

ERIC Educational Resources Information Center

Cajander, Asa; Daniels, Mats; McDermott, Roger

2012-01-01

This paper investigates the links between the "contributing student pedagogy" and other forms of peer-mediated learning models, e.g. "open-ended group projects" and "communities of practice." We find that a fundamental concern in each of these models is the attribution of "value"; specifically, recognition…

Public health nurses' contribution to maternal and infant health in Ireland.

PubMed

O'Dwyer, Patricia

2009-05-01

As the health practitioners most closely involved with new mothers and babies, public health nurses in Ireland have an important contribution to make to the health of this population group.They deliver a service of preventative health care to mothers and babies that begins in the postnatal period. This paper considers the role of the public health nurse in maternal and infant health, and explores the notion that public health nurses are afforded the appropriate opportunities to contribute to the health of this population group. In order to reduce the health inequalities that are known to exist for new mothers and babies, the commitment of the health executive is needed for the development of a new model of delivering nursing services in the community.

Responding to rural social care needs: older people empowering themselves, others and their community.

PubMed

Walsh, Kieran; O'Shea, Eamon

2008-12-01

Older adult active retirement groups encompass health promotion, social and community psychological potential. However, little is known about the internal dynamics of these groups or their contribution to individual well-being and the community. This paper examines the Third Age Foundation as an example of one such group operating in a rural area in Ireland and explores the various relationships at work internally and externally. Methodology included: structured and semi-structured interviews, focus groups and a postal survey. A substantial contribution to members' well-being and community competence and cohesion was found. Findings are discussed in reference to the importance of individual and community empowerment, sustainability, social entrepreneurship/leadership and the potential of such models to support community-based living in older age.

Effective behavioral modeling and prediction even when few exemplars are available

NASA Astrophysics Data System (ADS)

Goan, Terrance; Kartha, Neelakantan; Kaneshiro, Ryan

2006-05-01

While great progress has been made in the lowest levels of data fusion, practical advances in behavior modeling and prediction remain elusive. The most critical limitation of existing approaches is their inability to support the required knowledge modeling and continuing refinement under realistic constraints (e.g., few historic exemplars, the lack of knowledge engineering support, and the need for rapid system deployment). This paper reports on our ongoing efforts to develop Propheteer, a system which will address these shortcomings through two primary techniques. First, with Propheteer we abandon the typical consensus-driven modeling approaches that involve infrequent group decision making sessions in favor of an approach that solicits asynchronous knowledge contributions (in the form of alternative future scenarios and indicators) without burdening the user with endless certainty or probability estimates. Second, we enable knowledge contributions by personnel beyond the typical core decision making group, thereby casting light on blind spots, mitigating human biases, and helping maintain the currency of the developed behavior models. We conclude with a discussion of the many lessons learned in the development of our prototype Propheteer system.

How neglect and punitiveness influence emotion knowledge.

PubMed

Sullivan, Margaret Wolan; Carmody, Dennis P; Lewis, Michael

2010-06-01

To explore whether punitive parenting styles contribute to early-acquired emotion knowledge deficits observable in neglected children, we observed 42 preschool children's emotion knowledge, expression recognition time, and IQ. The children's mothers completed the Parent-Child Conflict Tactics Scales to assess the recent use of three types of discipline strategies (nonviolent, physically punitive, and psychological aggression), as well as neglectful parenting. Fifteen of the children were identified as neglected by Child Protective Services (CPS) reports; 27 children had no record of CPS involvement and served as the comparison group. There were no differences between the neglect and comparison groups in the demographic factors of gender, age, home language, minority status, or public assistance, nor on IQ. Hierarchical multiple regression modeling showed that neglect significantly predicted emotion knowledge. The addition of IQ contributed a significant amount of additional variance to the model and maintained the fit. Adding parental punitiveness in the final stage contributed little additional variance and did not significantly improve the fit. Thus, deficits in children's emotion knowledge may be due primarily to lower IQ or neglect. IQ was unrelated to speed of emotion recognition. Punitiveness did not directly contribute to emotion knowledge deficits but appeared in exploratory analysis to be related to speed of emotion recognition.

Simulating the Evolution of the Human Family: Cooperative Breeding Increases in Harsh Environments

PubMed Central

Smaldino, Paul E.; Newson, Lesley; Schank, Jeffrey C.; Richerson, Peter J.

2013-01-01

Verbal and mathematical models that consider the costs and benefits of behavioral strategies have been useful in explaining animal behavior and are often used as the basis of evolutionary explanations of human behavior. In most cases, however, these models do not account for the effects that group structure and cultural traditions within a human population have on the costs and benefits of its members' decisions. Nor do they consider the likelihood that cultural as well as genetic traits will be subject to natural selection. In this paper, we present an agent-based model that incorporates some key aspects of human social structure and life history. We investigate the evolution of a population under conditions of different environmental harshness and in which selection can occur at the level of the group as well as the level of the individual. We focus on the evolution of a socially learned characteristic related to individuals' willingness to contribute to raising the offspring of others within their family group. We find that environmental harshness increases the frequency of individuals who make such contributions. However, under the conditions we stipulate, we also find that environmental variability can allow groups to survive with lower frequencies of helpers. The model presented here is inevitably a simplified representation of a human population, but it provides a basis for future modeling work toward evolutionary explanations of human behavior that consider the influence of both genetic and cultural transmission of behavior. PMID:24278318

Simulating the evolution of the human family: cooperative breeding increases in harsh environments.

PubMed

Smaldino, Paul E; Newson, Lesley; Schank, Jeffrey C; Richerson, Peter J

2013-01-01

Verbal and mathematical models that consider the costs and benefits of behavioral strategies have been useful in explaining animal behavior and are often used as the basis of evolutionary explanations of human behavior. In most cases, however, these models do not account for the effects that group structure and cultural traditions within a human population have on the costs and benefits of its members' decisions. Nor do they consider the likelihood that cultural as well as genetic traits will be subject to natural selection. In this paper, we present an agent-based model that incorporates some key aspects of human social structure and life history. We investigate the evolution of a population under conditions of different environmental harshness and in which selection can occur at the level of the group as well as the level of the individual. We focus on the evolution of a socially learned characteristic related to individuals' willingness to contribute to raising the offspring of others within their family group. We find that environmental harshness increases the frequency of individuals who make such contributions. However, under the conditions we stipulate, we also find that environmental variability can allow groups to survive with lower frequencies of helpers. The model presented here is inevitably a simplified representation of a human population, but it provides a basis for future modeling work toward evolutionary explanations of human behavior that consider the influence of both genetic and cultural transmission of behavior.

Examining the Diet of Post-Migrant Hispanic Males Using the Precede-Proceed Model: Predisposing, Reinforcing, and Enabling Dietary Factors

ERIC Educational Resources Information Center

Castellanos, Diana Cuy; Downey, Laura; Graham-Kresge, Susan; Yadrick, Kathleen; Zoellner, Jamie; Connell, Carol L.

2013-01-01

Objective: To examine socio-environmental, behavioral, and predisposing, reinforcing, and enabling (PRE) factors contributing to post-migration dietary behavior change among a sample of traditional Hispanic males. Design: In this descriptive study, semistructured interviews, a group interview, and photovoice, followed by group interviews, were…

Does waist circumference uncorrelated with BMI add valuable information?

PubMed

Ngueta, Gerard; Laouan-Sidi, Elhadji A; Lucas, Michel

2014-09-01

Estimation of relative contribution of Body Mass Index (BMI) and waist circumference (WC) on health outcomes requires a regression model that includes both obesity metrics. But, multicollinearity could yield biased estimates. To address the multicollinearity issue between BMI and WC, we used the residual model approach. The standard WC (Y-axis) was regressed on the BMI (X-axis) to obtain residual WC. Data from two adult population surveys (Nunavik Inuit and James Bay Cree) were analysed to evaluate relative effect of BMI and WC on four cardiometabolic risk factors: insulin, triglycerides, systolic blood pressure and high-density lipoprotein levels. In multivariate models, standard WC and BMI were significantly associated with cardiometabolic outcomes. Residual WC was not linked with any outcomes. The BMI effect was weakened by including standard WC in the model, but its effect remained unchanged if residual WC was considered. The strong correlation between standard WC and BMI does not allow assessment of their relative contributions to health in the same model without a risk of making erroneous estimations. By contrast with BMI, fat distribution (residual WC) does not add valuable information to a model that already contains overall adiposity (BMI) in Inuit and Cree. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

The current contribution of molecular factors to risk estimation in neuroblastoma patients.

PubMed

Berthold, F; Sahin, K; Hero, B; Christiansen, H; Gehring, M; Harms, D; Horz, S; Lampert, F; Schwab, M; Terpe, J

1997-10-01

The association of molecular characteristics with prognosis has been reported, but not their relationship with each other and their impact in the context of known clinical risk factors. In this study, data of 1249 consecutive intent-to-treat-neuroblastoma patients with more than 1 year follow-up were examined by multivariate analysis using loglinear and Cox proportional hazard regression models on a stage-related basis (stages 1-3: 600, 4S: 116, 4: 533). In a first step, risk factors were identified from 18 selected clinical variables, and risk groups defined. The second step investigated whether molecular characteristics (MYCN, LOH 1p, del 1p, CD44, N-ras, NGF-R, bcl-2, APO-1 (CD95)) contributed additional prognostic information to the model. The loglinear model demonstrated several interactions between clinical factors. By the Cox regression model, seven independent clinical risk factors were found for stages 1-3, seven for stage 4 and two for stage 4S. By subsequent introduction of all molecular variables, MYCN amplification only added significant prognostic information to the clinical factors in localised and stage 4 neuroblastoma. The models allowed the definition of risk groups for stages 1-3 patients by age (e beta = 5.09) and MYCN (e beta = 4.26), for stage 4 by MYCN (e beta = 2.78) and number of symptoms (e beta = 2.44) and for stage 4S by platelet count (e beta = 3.91) and general condition (e beta = 2.99). Molecular factors and in particular MYCN contribute significantly to risk estimation. In conjunction with clinical factors, they are powerful tools to define risk groups in neuroblastoma.

Classroom Factors Affecting Students: Self-Evaluation: An Interactional Model.

ERIC Educational Resources Information Center

Marshall, Hermine H.; Weinstein, Rhona S.

1984-01-01

A complex interactional model of classroom factors that contribute to the development of students' self-evaluations is presented. Factors described are: (1) task structure; (2) grouping practices; (3) feedback and evaluation procedures and information about ability; (4) motivational strategies; (5) locus of responsibility for learning; and (6) the…

A Model of Student Workload

ERIC Educational Resources Information Center

Bowyer, Kyle

2012-01-01

Student workload is a contributing factor to students deciding to withdraw from their study before completion of the course, at significant cost to students, institutions and society. The aim of this paper is to create a basic workload model for a group of undergraduate students studying business law units at Curtin University in Western…

Food Sharing across Borders : First Observation of Intercommunity Meat Sharing by Bonobos at LuiKotale, DRC.

PubMed

Fruth, Barbara; Hohmann, Gottfried

2018-06-01

Evolutionary models consider hunting and food sharing to be milestones that paved the way from primate to human societies. Because fossil evidence is scarce, hominoid primates serve as referential models to assess our common ancestors' capacity in terms of communal use of resources, food sharing, and other forms of cooperation. Whereas chimpanzees form male-male bonds exhibiting resource-defense polygyny with intolerance and aggression toward nonresidents, bonobos form male-female and female-female bonds resulting in relaxed relations with neighboring groups. Here we report the first known case of meat sharing between members of two bonobo communities, revealing a new dimension of social tolerance in this species. This observation testifies to the behavioral plasticity that exists in the two Pan species and contributes to scenarios concerning the traits of the last common ancestor of Pan and Homo. It also contributes to the discussion of physiological triggers of in-group/out-group behavior and allows reconsideration of the emergence of social norms in prehuman societies.

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

PubMed

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

2012-05-01

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

Effects of aspirin on the ERK and PI3K/Akt signaling pathways in rats with acute pulmonary embolism.

PubMed

Wang, Lingcong; Wu, Jiannong; Zhang, Wei; Zhi, Yihui; Wu, Yanchun; Jiang, Ronglin; Yang, Ruhui

2013-11-01

Inflammation contributes to acute pulmonary embolism (APE). However, the contributions of the extracellular signal‑regulated protein kinases (ERK) and phosphoinositide 3 kinase/protein kinase B (PI3K/Akt) signaling pathways have not yet been elucidated. The aim of this study was to examine the effects of aspirin on ERK and PI3K/Akt signaling in a rat model of APE and evaluate the prognostic values of brain natriuretic peptide (BNP), troponin (TnT) and D‑Dimer. A total of 108 Sprague‑Dawley rats were assigned into the control, sham, model and low‑, medium‑ and high‑dose aspirin (150, 300 and 600 mg/kg, respectively) groups. In each group, six rats were sacrificed 6, 24 and 72 h subsequent to the induction of APE to collect the lungs and serum. Western blot analysis was used to assess ERK, PI3K and Akt expression; enzyme‑linked immunosorbent assay (ELISA) was used to analyze BNP, TnT and D‑Dimer levels; and changes in lung pathology were evaluated using hematoxylin and eosin (H&E) staining. The results showed that ERK and PI3K levels were decreased in the control, sham and the three aspirin groups at all time‑points compared with the model group (P<0.01). The exception was in the medium‑dose aspirin group at 24 h. The serum levels of BNP, TnT and D‑Dimer were lower in the control and sham groups at all time‑points compared with the model group (P<0.05). Furthermore, the levels of BNP, TnT and D‑Dimer levels were decreased in the aspirin‑treated groups (P<0.05) and markedly increased in the model group (P<0.05) at 24 h compared with the levels at 6 h. Pulmonary embolism, alveolar wall necrosis and hemorrhage were observed in the model group 6, 24 and 72 h subsequent to the induction of the model. However, congestion and inflammation were attenuated following aspirin treatment. In conclusion, aspirin reduces lung damage and improves prognosis. Decreased ERK, PI3K and Akt expression in the lungs and reduced levels of BNP, TnT and D‑Dimer may be important factors in the effects observed.

Review of Command and Control Models and Theory

DTIC Science & Technology

1990-09-01

or psychological pressures exerted with the intent to assure that an agent or group will respond as di- rected: (p. 88). Thus, while "command and...Organizational competence criteria are defined by using a modification to the criteria outlined by Bennis. Processes are then grouped in terms of wtich...1982) at- tempted to identify the skills and behaviors, used in battalion command and control groups , that contribute to effective performance. In

Docking and scoring protein complexes: CAPRI 3rd Edition.

PubMed

Lensink, Marc F; Méndez, Raúl; Wodak, Shoshana J

2007-12-01

The performance of methods for predicting protein-protein interactions at the atomic scale is assessed by evaluating blind predictions performed during 2005-2007 as part of Rounds 6-12 of the community-wide experiment on Critical Assessment of PRedicted Interactions (CAPRI). These Rounds also included a new scoring experiment, where a larger set of models contributed by the predictors was made available to groups developing scoring functions. These groups scored the uploaded set and submitted their own best models for assessment. The structures of nine protein complexes including one homodimer were used as targets. These targets represent biologically relevant interactions involved in gene expression, signal transduction, RNA, or protein processing and membrane maintenance. For all the targets except one, predictions started from the experimentally determined structures of the free (unbound) components or from models derived by homology, making it mandatory for docking methods to model the conformational changes that often accompany association. In total, 63 groups and eight automatic servers, a substantial increase from previous years, submitted docking predictions, of which 1994 were evaluated here. Fifteen groups submitted 305 models for five targets in the scoring experiment. Assessment of the predictions reveals that 31 different groups produced models of acceptable and medium accuracy-but only one high accuracy submission-for all the targets, except the homodimer. In the latter, none of the docking procedures reproduced the large conformational adjustment required for correct assembly, underscoring yet again that handling protein flexibility remains a major challenge. In the scoring experiment, a large fraction of the groups attained the set goal of singling out the correct association modes from incorrect solutions in the limited ensembles of contributed models. But in general they seemed unable to identify the best models, indicating that current scoring methods are probably not sensitive enough. With the increased focus on protein assemblies, in particular by structural genomics efforts, the growing community of CAPRI predictors is engaged more actively than ever in the development of better scoring functions and means of modeling conformational flexibility, which hold promise for much progress in the future. (c) 2007 Wiley-Liss, Inc.

Trends in inequalities in premature cancer mortality by educational level in Colombia, 1998-2007.

PubMed

de Vries, Esther; Arroyave, Ivan; Pardo, Constanza; Wiesner, Carolina; Murillo, Raul; Forman, David; Burdorf, Alex; Avendaño, Mauricio

2015-05-01

There is a paucity of studies on socioeconomic inequalities in cancer mortality in developing countries. We examined trends in inequalities in cancer mortality by educational attainment in Colombia during a period of epidemiological transition and rapid expansion of health insurance coverage. Population mortality data (1998-2007) were linked to census data to obtain age-standardised cancer mortality rates by educational attainment at ages 25-64 years for stomach, cervical, prostate, lung, colorectal, breast and other cancers. We used Poisson regression to model mortality by educational attainment and estimated the contribution of specific cancers to the slope index of inequality in cancer mortality. We observed large educational inequalities in cancer mortality, particularly for cancer of the cervix (rate ratio (RR) primary vs tertiary groups=5.75, contributing 51% of cancer inequalities), stomach (RR=2.56 for males, contributing 49% of total cancer inequalities and RR=1.98 for females, contributing 14% to total cancer inequalities) and lung (RR=1.64 for males contributing 17% of total cancer inequalities and 1.32 for females contributing 5% to total cancer inequalities). Total cancer mortality rates declined faster among those with higher education, with the exception of mortality from cervical cancer, which declined more rapidly in the lower educational groups. There are large socioeconomic inequalities in preventable cancer mortality in Colombia, which underscore the need for intensifying prevention efforts. Reduction of cervical cancer can be achieved through reducing human papilloma virus infection, early detection and improved access to treatment of preneoplastic lesions. Reinforcing antitobacco measures may be particularly important to curb inequalities in cancer mortality. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

From Data-Sharing to Model-Sharing: SCEC and the Development of Earthquake System Science (Invited)

NASA Astrophysics Data System (ADS)

Jordan, T. H.

2009-12-01

Earthquake system science seeks to construct system-level models of earthquake phenomena and use them to predict emergent seismic behavior—an ambitious enterprise that requires high degree of interdisciplinary, multi-institutional collaboration. This presentation will explore model-sharing structures that have been successful in promoting earthquake system science within the Southern California Earthquake Center (SCEC). These include disciplinary working groups to aggregate data into community models; numerical-simulation working groups to investigate system-specific phenomena (process modeling) and further improve the data models (inverse modeling); and interdisciplinary working groups to synthesize predictive system-level models. SCEC has developed a cyberinfrastructure, called the Community Modeling Environment, that can distribute the community models; manage large suites of numerical simulations; vertically integrate the hardware, software, and wetware needed for system-level modeling; and promote the interactions among working groups needed for model validation and refinement. Various socio-scientific structures contribute to successful model-sharing. Two of the most important are “communities of trust” and collaborations between government and academic scientists on mission-oriented objectives. The latter include improvements of earthquake forecasts and seismic hazard models and the use of earthquake scenarios in promoting public awareness and disaster management.

A Group Increment Scheme for Infrared Absorption Intensities of Greenhouse Gases

NASA Technical Reports Server (NTRS)

Kokkila, Sara I.; Bera, Partha P.; Francisco, Joseph S.; Lee, Timothy J.

2012-01-01

A molecule's absorption in the atmospheric infrared (IR) window (IRW) is an indicator of its efficiency as a greenhouse gas. A model for estimating the absorption of a fluorinated molecule within the IRW was developed to assess its radiative impact. This model will be useful in comparing different hydrofluorocarbons and hydrofluoroethers contribution to global warming. The absorption of radiation by greenhouse gases, in particular hydrofluoroethers and hydrofluorocarbons, was investigated using ab initio quantum mechanical methods. Least squares regression techniques were used to create a model based on this data. The placement and number of fluorines in the molecule were found to affect the absorption in the IR window and were incorporated into the model. Several group increment models are discussed. An additive model based on one-carbon groups is found to work satisfactorily in predicting the ab initio calculated vibrational intensities.

Solubility Prediction of Active Pharmaceutical Compounds with the UNIFAC Model

NASA Astrophysics Data System (ADS)

Nouar, Abderrahim; Benmessaoud, Ibtissem; Koutchoukali, Ouahiba; Koutchoukali, Mohamed Salah

2016-03-01

The crystallization from solution of an active pharmaceutical ingredient requires the knowledge of the solubility in the entire temperature range investigated during the process. However, during the development of a new active ingredient, these data are missing. Its experimental determination is possible, but tedious. UNIFAC Group contribution method Fredenslund et al. (Vapor-liquid equilibria using UNIFAC: a group contribution method, 1977; AIChE J 21:1086, 1975) can be used to predict this physical property. Several modifications on this model have been proposed since its development in 1977, modified UNIFAC of Dortmund Weidlich et al. (Ind Eng Chem Res 26:1372, 1987), Gmehling et al. (Ind Eng Chem Res 32:178, 1993), Pharma-modified UNIFAC Diedrichs et al. (Evaluation und Erweiterung thermodynamischer Modelle zur Vorhersage von Wirkstofflöslichkeiten, PhD Thesis, 2010), KT-UNIFAC Kang et al. (Ind Eng Chem Res 41:3260, 2002), ldots In this study, we used UNIFAC model by considering the linear temperature dependence of interaction parameters as in Pharma-modified UNIFAC and structural groups as defined by KT-UNIFAC first-order model. More than 100 binary datasets were involved in the estimation of interaction parameters. These new parameters were then used to calculate activity coefficient and solubility of some molecules in various solvents at different temperatures. The model gives better results than those from the original UNIFAC and shows good agreement between the experimental solubility and the calculated one.

Cumulative dietary exposure to a selected group of pesticides of the triazole group in different European countries according to the EFSA guidance on probabilistic modelling.

PubMed

Boon, Polly E; van Donkersgoed, Gerda; Christodoulou, Despo; Crépet, Amélie; D'Addezio, Laura; Desvignes, Virginie; Ericsson, Bengt-Göran; Galimberti, Francesco; Ioannou-Kakouri, Eleni; Jensen, Bodil Hamborg; Rehurkova, Irena; Rety, Josselin; Ruprich, Jiri; Sand, Salomon; Stephenson, Claire; Strömberg, Anita; Turrini, Aida; van der Voet, Hilko; Ziegler, Popi; Hamey, Paul; van Klaveren, Jacob D

2015-05-01

The practicality was examined of performing a cumulative dietary exposure assessment according to the requirements of the EFSA guidance on probabilistic modelling. For this the acute and chronic cumulative exposure to triazole pesticides was estimated using national food consumption and monitoring data of eight European countries. Both the acute and chronic cumulative dietary exposures were calculated according to two model runs (optimistic and pessimistic) as recommended in the EFSA guidance. The exposures obtained with these model runs differed substantially for all countries, with the highest exposures obtained with the pessimistic model run. In this model run, animal commodities including cattle milk and different meat types, entered in the exposure calculations at the level of the maximum residue limit (MRL), contributed most to the exposure. We conclude that application of the optimistic model run on a routine basis for cumulative assessments is feasible. The pessimistic model run is laborious and the exposure results could be too far from reality. More experience with this approach is needed to stimulate the discussion of the feasibility of all the requirements, especially the inclusion of MRLs of animal commodities which seem to result in unrealistic conclusions regarding their contribution to the dietary exposure. Copyright © 2014 Elsevier Ltd. All rights reserved.

A neural hypothesis for stress-induced headache.

PubMed

Cathcart, Stuart

2009-12-01

The mechanisms by which stress contributes to CTH are not clearly understood. The commonly accepted notion of muscle hyper-reactivity to stress in CTH sufferers is not supported in the research data. We propose a neural model whereby stress acts supra-spinally to aggravate already increased pain sensitivity in CTH sufferers. Indirect support for the model comes from emerging research elucidating complex supra-spinal networks through which psychological stress may contribute to and even cause pain. Similarly, emerging research demonstrates supra-spinal pain processing abnormalities in CTH sufferers. While research with CTH sufferers offering direct support for the model is lacking at present, initial work by our group is consistent with the models predictions, particularly, that stress aggravates already increased pain sensitivity in CTH sufferers.

Revised simulation model does not predict rebound in gonorrhoea prevalence where core groups are treated in the presence of antimicrobial resistance.

PubMed

Trecker, Molly A; Hogan, Daniel J; Waldner, Cheryl L; Dillon, Jo-Anne R; Osgood, Nathaniel D

2015-06-01

To determine the effects of using discrete versus continuous quantities of people in a compartmental model examining the contribution of antimicrobial resistance (AMR) to rebound in the prevalence of gonorrhoea. A previously published transmission model was reconfigured to represent the occurrence of gonorrhoea in discrete persons, rather than allowing fractions of infected individuals during simulations. In the revised model, prevalence only rebounded under scenarios reproduced from the original paper when AMR occurrence was increased by 10(5) times. In such situations, treatment of high-risk individuals yielded outcomes very similar to those resulting from treatment of low-risk and intermediate-risk individuals. Otherwise, in contrast with the original model, prevalence was the lowest when the high-risk group was treated, supporting the current policy of targeting treatment to high-risk groups. Simulation models can be highly sensitive to structural features. Small differences in structure and parameters can substantially influence predicted outcomes and policy prescriptions, and must be carefully considered. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Revisiting the Dielectric Constant Effect on the Nucleophile and Leaving Group of Prototypical Backside Sn2 Reactions: a Reaction Force and Atomic Contribution Analysis.

PubMed

Pedraza-González, Laura Milena; Galindo, Johan Fabian; Gonzalez, Ronald; Reyes, Andrés

2016-10-09

The solvent effect on the nucleophile and leaving group atoms of the prototypical F - + CH 3 Cl → CH 3 F + Cl - backside bimolecular nucleophilic substitution reaction (S N 2) is analyzed employing the reaction force and the atomic contributions methods on the intrinsic reaction coordinate (IRC). Solvent effects were accounted for using the polarizable continuum solvent model. Calculations were performed employing eleven dielectric constants, ε, ranging from 1.0 to 78.5, to cover a wide spectrum of solvents. The reaction force data reveals that the solvent mainly influences the region of the IRC preceding the energy barrier, where the structural rearrangement to reach the transition state occurs. A detailed analysis of the atomic role in the reaction as a function of ε reveals that the nucleophile and the carbon atom are the ones that contribute the most to the energy barrier. In addition, we investigated the effect of the choice of nucleophile and leaving group on the ΔE 0 and ΔE ↕ of Y - + CH 3 X → YCH 3 + X - (X,Y= F, Cl, Br, I) in aqueous solution. Our analysis allowed us to find relationships between the atomic contributions to the activation energy and leaving group ability and nucleophilicity.

Characterization of Musa sp. fruits and plantain banana ripening stages according to their physicochemical attributes.

PubMed

Valérie Passo Tsamo, Claudine; Andre, Christelle M; Ritter, Christian; Tomekpe, Kodjo; Ngoh Newilah, Gérard; Rogez, Hervé; Larondelle, Yvan

2014-08-27

This study aimed at understanding the contribution of the fruit physicochemical parameters to Musa sp. diversity and plantain ripening stages. A discriminant analysis was first performed on a collection of 35 Musa sp. cultivars, organized in six groups based on the consumption mode (dessert or cooking banana) and the genomic constitution. A principal component analysis reinforced by a logistic regression on plantain cultivars was proposed as an analytical approach to describe the plantain ripening stages. The results of the discriminant analysis showed that edible fraction, peel pH, pulp water content, and pulp total phenolics were among the most contributing attributes for the discrimination of the cultivar groups. With mean values ranging from 65.4 to 247.3 mg of gallic acid equivalents/100 g of fresh weight, the pulp total phenolics strongly differed between interspecific and monospecific cultivars within dessert and nonplantain cooking bananas. The results of the logistic regression revealed that the best models according to fitting parameters involved more than one physicochemical attribute. Interestingly, pulp and peel total phenolic contents contributed in the building up of these models.

A geostatistics-informed hierarchical sensitivity analysis method for complex groundwater flow and transport modeling

NASA Astrophysics Data System (ADS)

Dai, Heng; Chen, Xingyuan; Ye, Ming; Song, Xuehang; Zachara, John M.

2017-05-01

Sensitivity analysis is an important tool for development and improvement of mathematical models, especially for complex systems with a high dimension of spatially correlated parameters. Variance-based global sensitivity analysis has gained popularity because it can quantify the relative contribution of uncertainty from different sources. However, its computational cost increases dramatically with the complexity of the considered model and the dimension of model parameters. In this study, we developed a new sensitivity analysis method that integrates the concept of variance-based method with a hierarchical uncertainty quantification framework. Different uncertain inputs are grouped and organized into a multilayer framework based on their characteristics and dependency relationships to reduce the dimensionality of the sensitivity analysis. A set of new sensitivity indices are defined for the grouped inputs using the variance decomposition method. Using this methodology, we identified the most important uncertainty source for a dynamic groundwater flow and solute transport model at the Department of Energy (DOE) Hanford site. The results indicate that boundary conditions and permeability field contribute the most uncertainty to the simulated head field and tracer plume, respectively. The relative contribution from each source varied spatially and temporally. By using a geostatistical approach to reduce the number of realizations needed for the sensitivity analysis, the computational cost of implementing the developed method was reduced to a practically manageable level. The developed sensitivity analysis method is generally applicable to a wide range of hydrologic and environmental problems that deal with high-dimensional spatially distributed input variables.

A Geostatistics-Informed Hierarchical Sensitivity Analysis Method for Complex Groundwater Flow and Transport Modeling

NASA Astrophysics Data System (ADS)

Dai, H.; Chen, X.; Ye, M.; Song, X.; Zachara, J. M.

2017-12-01

Sensitivity analysis is an important tool for development and improvement of mathematical models, especially for complex systems with a high dimension of spatially correlated parameters. Variance-based global sensitivity analysis has gained popularity because it can quantify the relative contribution of uncertainty from different sources. However, its computational cost increases dramatically with the complexity of the considered model and the dimension of model parameters. In this study we developed a new sensitivity analysis method that integrates the concept of variance-based method with a hierarchical uncertainty quantification framework. Different uncertain inputs are grouped and organized into a multi-layer framework based on their characteristics and dependency relationships to reduce the dimensionality of the sensitivity analysis. A set of new sensitivity indices are defined for the grouped inputs using the variance decomposition method. Using this methodology, we identified the most important uncertainty source for a dynamic groundwater flow and solute transport model at the Department of Energy (DOE) Hanford site. The results indicate that boundary conditions and permeability field contribute the most uncertainty to the simulated head field and tracer plume, respectively. The relative contribution from each source varied spatially and temporally. By using a geostatistical approach to reduce the number of realizations needed for the sensitivity analysis, the computational cost of implementing the developed method was reduced to a practically manageable level. The developed sensitivity analysis method is generally applicable to a wide range of hydrologic and environmental problems that deal with high-dimensional spatially-distributed input variables.

Prediction of cloud condensation nuclei activity for organic compounds using functional group contribution methods

DOE PAGES

Petters, M. D.; Kreidenweis, S. M.; Ziemann, P. J.

2016-01-19

A wealth of recent laboratory and field experiments demonstrate that organic aerosol composition evolves with time in the atmosphere, leading to changes in the influence of the organic fraction to cloud condensation nuclei (CCN) spectra. There is a need for tools that can realistically represent the evolution of CCN activity to better predict indirect effects of organic aerosol on clouds and climate. This work describes a model to predict the CCN activity of organic compounds from functional group composition. Following previous methods in the literature, we test the ability of semi-empirical group contribution methods in Kohler theory to predict themore » effective hygroscopicity parameter, kappa. However, in our approach we also account for liquid–liquid phase boundaries to simulate phase-limited activation behavior. Model evaluation against a selected database of published laboratory measurements demonstrates that kappa can be predicted within a factor of 2. Simulation of homologous series is used to identify the relative effectiveness of different functional groups in increasing the CCN activity of weakly functionalized organic compounds. Hydroxyl, carboxyl, aldehyde, hydroperoxide, carbonyl, and ether moieties promote CCN activity while methylene and nitrate moieties inhibit CCN activity. Furthermore, the model can be incorporated into scale-bridging test beds such as the Generator of Explicit Chemistry and Kinetics of Organics in the Atmosphere (GECKO-A) to evaluate the evolution of kappa for a complex mix of organic compounds and to develop suitable parameterizations of CCN evolution for larger-scale models.« less

Prioritization of pesticides based on daily dietary exposure potential as determined from the SHEDS model.

PubMed

Melnyk, Lisa Jo; Wang, Zhaohui; Li, Zhilin; Xue, Jianping

2016-10-01

A major pathway for exposure to many pesticides is through diet. The objectives were to rank pesticides by comparing their calculated daily dietary exposure as determined by EPA's Stochastic Human Exposure and Dose Simulation (SHEDS) to single pesticides for different age groups to acceptable daily intakes (ADI), characterize pesticide trends in exposures over different time periods, and determine commodities contributing to pesticide exposures. SHEDS was applied, using Pesticide Data Program (PDP) (1991-2011) and pesticide usage data on crops from USDA combined with NHANES dietary consumption data, to generate exposure estimates by age group. ADI data collected from EPA, WHO, and other sources were used to rank pesticides based on relativeness of the dietary exposure potential to ADI by age groups. Sensitivity analysis provided trends in pesticide exposures. Within SHEDS, commodities contributing the majority of pesticides with greatest exposure potential were determined. The results indicated that the highest ranking pesticides were methamidophos and diazinon which exceeded 100% of the ADI. Sensitivity analysis indicated that exposure to methamidophos, diazinon, malathion, ethion and formetanate hydrochloride had a marked decrease from 1991-1999 to 2000-2011. Contributions analysis indicated that apples, mushroom, carrots, and lettuce contributed to diazinon exposure. Beans and pepper contributed to methamidophos exposure. Published by Elsevier Ltd.

Elementary Particle Physics Experiment at the University of Massachusetts, Amherst

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

Brau, Benjamin; Dallapiccola, Carlo; Willocq, Stephane

2013-07-30

In this progress report we summarize the activities of the University of Massachusetts- Amherst group for the three years of this research project. We are fully engaged in research at the energy frontier with the ATLAS experiment at the CERN Large Hadron Collider. We have made leading contributions in software development and performance studies for the ATLAS Muon Spectrometer, as well as on physics analysis with an emphasis on Standard Model measurements and searches for physics beyond the Standard Model. In addition, we have increased our contributions to the Muon Spectrometer New Small Wheel upgrade project.

How Neglect and Punitiveness Influence Emotion Knowledge

PubMed Central

Sullivan, Margaret Wolan; Carmody, Dennis P.

2010-01-01

To explore whether punitive parenting styles contribute to early-acquired emotion knowledge deficits observable in neglected children, we observed 42 preschool children’s emotion knowledge, expression recognition time, and IQ. The children’s mothers completed the Parent–Child Conflict Tactics Scales to assess the recent use of three types of discipline strategies (nonviolent, physically punitive, and psychological aggression), as well as neglectful parenting. Fifteen of the children were identified as neglected by Child Protective Services (CPS) reports; 27 children had no record of CPS involvement and served as the comparison group. There were no differences between the neglect and comparison groups in the demographic factors of gender, age, home language, minority status, or public assistance, nor on IQ. Hierarchical multiple regression modeling showed that neglect significantly predicted emotion knowledge. The addition of IQ contributed a significant amount of additional variance to the model and maintained the fit. Adding parental punitiveness in the final stage contributed little additional variance and did not significantly improve the fit. Thus, deficits in children’s emotion knowledge may be due primarily to lower IQ or neglect. IQ was unrelated to speed of emotion recognition. Punitiveness did not directly contribute to emotion knowledge deficits but appeared in exploratory analysis to be related to speed of emotion recognition. PMID:20099078

Landslides! Engaging students in natural hazards and STEM principles through the exploration of landslide analog models

NASA Astrophysics Data System (ADS)

Gochis, E. E.; Lechner, H. N.; Brill, K. A.; Lerner, G.; Ramos, E.

2014-12-01

Graduate students at Michigan Technological University developed the "Landslides!" activity to engage middle & high school students participating in summer engineering programs in a hands-on exploration of geologic engineering and STEM (Science, Technology, Engineering and Math) principles. The inquiry-based lesson plan is aligned to Next Generation Science Standards and is appropriate for 6th-12th grade classrooms. During the activity students focus on the factors contributing to landslide development and engineering practices used to mitigate hazards of slope stability hazards. Students begin by comparing different soil types and by developing predictions of how sediment type may contribute to differences in slope stability. Working in groups, students then build tabletop hill-slope models from the various materials in order to engage in evidence-based reasoning and test their predictions by adding groundwater until each group's modeled slope fails. Lastly students elaborate on their understanding of landslides by designing 'engineering solutions' to mitigate the hazards observed in each model. Post-evaluations from students demonstrate that they enjoyed the hands-on nature of the activity and the application of engineering principles to mitigate a modeled natural hazard.

Comparison of prediction methods for octanol-air partition coefficients of diverse organic compounds.

PubMed

Fu, Zhiqiang; Chen, Jingwen; Li, Xuehua; Wang, Ya'nan; Yu, Haiying

2016-04-01

The octanol-air partition coefficient (KOA) is needed for assessing multimedia transport and bioaccumulability of organic chemicals in the environment. As experimental determination of KOA for various chemicals is costly and laborious, development of KOA estimation methods is necessary. We investigated three methods for KOA prediction, conventional quantitative structure-activity relationship (QSAR) models based on molecular structural descriptors, group contribution models based on atom-centered fragments, and a novel model that predicts KOA via solvation free energy from air to octanol phase (ΔGO(0)), with a collection of 939 experimental KOA values for 379 compounds at different temperatures (263.15-323.15 K) as validation or training sets. The developed models were evaluated with the OECD guidelines on QSAR models validation and applicability domain (AD) description. Results showed that although the ΔGO(0) model is theoretically sound and has a broad AD, the prediction accuracy of the model is the poorest. The QSAR models perform better than the group contribution models, and have similar predictability and accuracy with the conventional method that estimates KOA from the octanol-water partition coefficient and Henry's law constant. One QSAR model, which can predict KOA at different temperatures, was recommended for application as to assess the long-range transport potential of chemicals. Copyright © 2016 Elsevier Ltd. All rights reserved.

Reliability and validity of the Norwegian WHOQOL-OLD module.

PubMed

Halvorsrud, Liv; Kalfoss, Mary; Diseth, Age

2008-06-01

The aim of this study was to examine the validity and reliability of the Norwegian WHOQOL-OLD six-facet, 24-item module designed for assessing generic quality of life cross-culturally among the elderly. Using quota-stratified sampling defined on the basis of sex, age and geographical representation, 401 respondents were drawn from Statistics Norway and completed postal surveys. An additional 89 elderly completed personal interviews. Correlation and multivariate analyses partly confirmed the relevance of individual items and facets in both groups. All items correlated significantly higher with their original facets, although almost half of these items correlated with other facets in both groups. Multiple regression analysis of the module and two overall questions (dependent variables) showed that three facets made significant contributions to overall health, with Social Participation (B = 0.09) contributing most strongly in the postal-group. In the interview-group, only Social Participation (B = 0.20) was found to make a significant contribution, and this was in relation to overall health satisfaction. When the WHOQOL-BREF total score was considered as the dependent variable, different facets contributed significantly in both groups. Exploratory factor analysis of the WHOQOL-OLD in the combined group of both postal and interview samples, resulted in a five-factor solution (eigenvalues >1) explaining 65% of the cumulative variance in five of the six originally operationalized facets. The most conceptually clear facets were Death and Dying and Sensory Abilities. Further, confirmatory factor analyses in the combined group demonstrated a model with good fit, but with high covariance between the factors. Acceptable internal consistency was shown except for the Past, Present and Future Activities in both groups. Since construct validity was only partially confirmed, exploration of the scale's conceptual validity needs further testing in Norwegian and international samples.

Analysis of change in gait in the ovine stifle: normal, injured, and anterior cruciate ligament reconstructed.

PubMed

Heard, B J; Beveridge, J E; Atarod, M; O'Brien, E J; Rolian, C; Frank, C B; Hart, D A; Shrive, N G

2017-05-23

Many patients who undergo anterior cruciate ligament (ACL) reconstructive surgery develop post-traumatic osteoarthritis (PTOA). ACL reconstructive surgery may not fully restore pre-injury joint biomechanics, thereby resulting in further joint damage and contributing to the development of PTOA. In an ovine model of idealized ACL reconstruction (ACL-R), it has been shown that signs of PTOA develop within surgical joints by 20 weeks post-surgery. The aim of the present study was to investigate whether altered kinematics contribute to early PTOA development within ACL-R joints of the ovine injury model by comparing the gait of these surgical animals to the gait of a stable normal control group, and an unstable injury group in which the ACL and medial collateral ligament (MCL) had been transected. Fifteen skeletally mature female sheep were allocated evenly into 3 treatment groups: normal control, ACL-R, and ACL/MCL Tx (each group n = 5). Each animal's gait was recorded at baseline, 4 weeks post injury, and 20 weeks post injury. Principal component analysis (PCA) was used to identify the kinematic patterns that may be discriminant between treatment groups. Results from previous studies were referenced to present the amount of gross PTOA-like changes that occurred in the joints. ACL-R and ACL/MCL transected (Tx) animals developed a similar amount of early PTOA-like changes within the surgical joints, but differed significantly in the amount of kinematic change present at 20 weeks post-surgery. We showed that the stifle joint kinematics of ACL/MCL Tx differed significantly from those of CTRL and the majority of ACL-R animals, while no significant differences in joint kinematic changes were found between ACL-R and CTRL animals. These results suggest that the early PTOA-like changes reported in the ACL-R model cannot be attributed exclusively to post-surgical kinematic changes, and therefore biologic components in the post-injury environment must be contributing significantly to PTOA development.

An Integrated Environment for Efficient Formal Design and Verification

NASA Technical Reports Server (NTRS)

1998-01-01

The general goal of this project was to improve the practicality of formal methods by combining techniques from model checking and theorem proving. At the time the project was proposed, the model checking and theorem proving communities were applying different tools to similar problems, but there was not much cross-fertilization. This project involved a group from SRI that had substantial experience in the development and application of theorem-proving technology, and a group at Stanford that specialized in model checking techniques. Now, over five years after the proposal was submitted, there are many research groups working on combining theorem-proving and model checking techniques, and much more communication between the model checking and theorem proving research communities. This project contributed significantly to this research trend. The research work under this project covered a variety of topics: new theory and algorithms; prototype tools; verification methodology; and applications to problems in particular domains.

"Who I Work with Is Important": Dyslexic Students' Narratives about the Benefits of Grouping for Instruction in Caribbean Classrooms

ERIC Educational Resources Information Center

Blackman, Stacey

2010-01-01

This article utilises a multiple case study strategy to explore the narratives of Caribbean students with dyslexia on grouping for instruction. It presents a model on learner engagement which highlights students' cognitions about the social and cognitive aspects of learning and the processes that contribute to building knowledge and understanding.…

Swine Model of Thrombotic Caval Occlusion Created by Autologous Thrombus Injection with Assistance of Intra-caval Net Knitting

PubMed Central

Shi, Wan-Yin; Wu, Shuang; Hu, Lan-Yue; Liu, Chang-Jian; Gu, Jian-Ping

2015-01-01

To evaluate the feasibility of a swine model of thrombotic inferior vena cava (IVC) occlusion (IVCO) created by autologous thrombus injection with assistance of intra-caval net knitting. Sixteen pigs were included and divided into two groups: Group A (n = 10), IVCO model created by knitting a caval net followed by autologous thrombus injection; Group B (n = 6), control model created by knitting a net and normal saline injection. Venography was performed to assess each model and the associated thrombotic occlusion. The vessels were examined histologically to analyse the pathological changes postoperatively. IVCO model was successfully created in 10 animals in Group A (100%). Immediate venography showed extensive clot burden in the IVC. Postoperative venography revealed partial caval occlusion at 7 days, and complete occlusion coupled with collateral vessels at 14 days. Histologically, Group A animals had significantly greater venous wall thickening, with CD163-positive and CD3-positive cell infiltration. Recanalization channels were observed at the margins of the thrombus. By contrast, no thrombotic occlusion of the IVC was observed in Group B. The thrombotic IVCO model can be reliably established in swine. The inflammatory reaction may contribute to the caval thrombus propagation following occlusion. PMID:26680253

Using system dynamics for collaborative design: a case study

PubMed Central

Elf, Marie; Putilova, Mariya; von Koch, Lena; Öhrn, Kerstin

2007-01-01

Background In order to facilitate the collaborative design, system dynamics (SD) with a group modelling approach was used in the early stages of planning a new stroke unit. During six workshops a SD model was created in a multiprofessional group. Aim To explore to which extent and how the use of system dynamics contributed to the collaborative design process. Method A case study was conducted using several data sources. Results SD supported a collaborative design, by facilitating an explicit description of stroke care process, a dialogue and a joint understanding. The construction of the model obliged the group to conceptualise the stroke care and experimentation with the model gave the opportunity to reflect on care. Conclusion SD facilitated the collaborative design process and should be integrated in the early stages of the design process as a quality improvement tool. PMID:17683519

Quantization of the nonlinear sigma model revisited

NASA Astrophysics Data System (ADS)

Nguyen, Timothy

2016-08-01

We revisit the subject of perturbatively quantizing the nonlinear sigma model in two dimensions from a rigorous, mathematical point of view. Our main contribution is to make precise the cohomological problem of eliminating potential anomalies that may arise when trying to preserve symmetries under quantization. The symmetries we consider are twofold: (i) diffeomorphism covariance for a general target manifold; (ii) a transitive group of isometries when the target manifold is a homogeneous space. We show that there are no anomalies in case (i) and that (ii) is also anomaly-free under additional assumptions on the target homogeneous space, in agreement with the work of Friedan. We carry out some explicit computations for the O(N)-model. Finally, we show how a suitable notion of the renormalization group establishes the Ricci flow as the one loop renormalization group flow of the nonlinear sigma model.

Boiling points of halogenated aliphatic compounds: a quantitative structure-property relationship for prediction and validation.

PubMed

Oberg, Tomas

2004-01-01

Halogenated aliphatic compounds have many technical uses, but substances within this group are also ubiquitous environmental pollutants that can affect the ozone layer and contribute to global warming. The establishment of quantitative structure-property relationships is of interest not only to fill in gaps in the available database but also to validate experimental data already acquired. The three-dimensional structures of 240 compounds were modeled with molecular mechanics prior to the generation of empirical descriptors. Two bilinear projection methods, principal component analysis (PCA) and partial-least-squares regression (PLSR), were used to identify outliers. PLSR was subsequently used to build a multivariate calibration model by extracting the latent variables that describe most of the covariation between the molecular structure and the boiling point. Boiling points were also estimated with an extension of the group contribution method of Stein and Brown.

High-order-harmonic generation from solids: The contributions of the Bloch wave packets moving at the group and phase velocities

NASA Astrophysics Data System (ADS)

Du, Tao-Yuan; Huang, Xiao-Huan; Bian, Xue-Bin

2018-01-01

We study numerically the Bloch electron wave-packet dynamics in periodic potentials to simulate laser-solid interactions. We introduce an alternative perspective in the coordinate space combined with the motion of the Bloch electron wave packets moving at group and phase velocities under the laser fields. This model interprets the origins of the two contributions (intra- and interband transitions) in the high-order harmonic generation (HHG) processes by investigating the local and global behaviours of the wave packets. It also elucidates the underlying physical picture of the HHG intensity enhancement by means of carrier-envelope phase, chirp, and inhomogeneous fields. It provides a deep insight into the emission of high-order harmonics from solids. This model is instructive for experimental measurements and provides an alternative avenue to distinguish mechanisms of the HHG from solids in different laser fields.

Deciphering the crowd: modeling and identification of pedestrian group motion.

PubMed

Yücel, Zeynep; Zanlungo, Francesco; Ikeda, Tetsushi; Miyashita, Takahiro; Hagita, Norihiro

2013-01-14

Associating attributes to pedestrians in a crowd is relevant for various areas like surveillance, customer profiling and service providing. The attributes of interest greatly depend on the application domain and might involve such social relations as friends or family as well as the hierarchy of the group including the leader or subordinates. Nevertheless, the complex social setting inherently complicates this task. We attack this problem by exploiting the small group structures in the crowd. The relations among individuals and their peers within a social group are reliable indicators of social attributes. To that end, this paper identifies social groups based on explicit motion models integrated through a hypothesis testing scheme. We develop two models relating positional and directional relations. A pair of pedestrians is identified as belonging to the same group or not by utilizing the two models in parallel, which defines a compound hypothesis testing scheme. By testing the proposed approach on three datasets with different environmental properties and group characteristics, it is demonstrated that we achieve an identification accuracy of 87% to 99%. The contribution of this study lies in its definition of positional and directional relation models, its description of compound evaluations, and the resolution of ambiguities with our proposed uncertainty measure based on the local and global indicators of group relation.

Deciphering the Crowd: Modeling and Identification of Pedestrian Group Motion

PubMed Central

Yücel, Zeynep; Zanlungo, Francesco; Ikeda, Tetsushi; Miyashita, Takahiro; Hagita, Norihiro

2013-01-01

Associating attributes to pedestrians in a crowd is relevant for various areas like surveillance, customer profiling and service providing. The attributes of interest greatly depend on the application domain and might involve such social relations as friends or family as well as the hierarchy of the group including the leader or subordinates. Nevertheless, the complex social setting inherently complicates this task. We attack this problem by exploiting the small group structures in the crowd. The relations among individuals and their peers within a social group are reliable indicators of social attributes. To that end, this paper identifies social groups based on explicit motion models integrated through a hypothesis testing scheme. We develop two models relating positional and directional relations. A pair of pedestrians is identified as belonging to the same group or not by utilizing the two models in parallel, which defines a compound hypothesis testing scheme. By testing the proposed approach on three datasets with different environmental properties and group characteristics, it is demonstrated that we achieve an identification accuracy of 87% to 99%. The contribution of this study lies in its definition of positional and directional relation models, its description of compound evaluations, and the resolution of ambiguities with our proposed uncertainty measure based on the local and global indicators of group relation. PMID:23344382

Fuel treatment effects on modeled landscape level fire behavior in the northern Sierra Nevada

Treesearch

J.J. Moghaddas; B.M. Collins; K. Menning; E.E.Y. Moghaddas; S.L. Stephens

2010-01-01

Across the western United States, decades of fire exclusion combined with past management history have contributed to the current condition of extensive areas of high-density, shade-tolerant coniferous stands that are increasingly prone to high-severity fires. Here, we report the modeled effects of constructed defensible fuel profile zones and group selection...

The development of a successful physician compensation plan.

PubMed

Berkowitz, Steven M

2002-10-01

Physician compensation plans are critical to the success of a physician group or may lead to the demise of the group. Essential components of the development and implementation of a successful physician compensation plan include: strategic planning, physician understanding and buy-in, appropriate incentives, objective performance measurement, and a specific funding source or mechanism. There are two basic philosophies to consider for use: the market-based model and the net economic contribution model. Advantages and disadvantages of each are discussed. Methods of incorporating these multiple aspects into a single plan are described.

Theoretical investigation of local proton conductance in the proton exchange membranes

NASA Astrophysics Data System (ADS)

Singh, Raman K.; Tsuneda, Takao; Miyatake, Kenji; Watanabe, Masahiro

2014-07-01

The hydrated structures of the proton exchange membranes were theoretically investigated using long-range corrected density functional theory to make clear why perfluorinated polymer membrane Nafion is superior to other membranes in the proton conductivity at low humidity. For exploring the possibility of the proton conductance in the vehicle mechanism with low hydration numbers, we examined the relay model of protonated water clusters between the sulfonic acid groups in Nafion and concluded that this relay model may contribute to the high proton conductivity of Nafion with less-hydrated sulfonic acid groups.

Estimation of environment-related properties of chemicals for design of sustainable processes: development of group-contribution+ (GC+) property models and uncertainty analysis.

PubMed

Hukkerikar, Amol Shivajirao; Kalakul, Sawitree; Sarup, Bent; Young, Douglas M; Sin, Gürkan; Gani, Rafiqul

2012-11-26

The aim of this work is to develop group-contribution(+) (GC(+)) method (combined group-contribution (GC) method and atom connectivity index (CI) method) based property models to provide reliable estimations of environment-related properties of organic chemicals together with uncertainties of estimated property values. For this purpose, a systematic methodology for property modeling and uncertainty analysis is used. The methodology includes a parameter estimation step to determine parameters of property models and an uncertainty analysis step to establish statistical information about the quality of parameter estimation, such as the parameter covariance, the standard errors in predicted properties, and the confidence intervals. For parameter estimation, large data sets of experimentally measured property values of a wide range of chemicals (hydrocarbons, oxygenated chemicals, nitrogenated chemicals, poly functional chemicals, etc.) taken from the database of the US Environmental Protection Agency (EPA) and from the database of USEtox is used. For property modeling and uncertainty analysis, the Marrero and Gani GC method and atom connectivity index method have been considered. In total, 22 environment-related properties, which include the fathead minnow 96-h LC(50), Daphnia magna 48-h LC(50), oral rat LD(50), aqueous solubility, bioconcentration factor, permissible exposure limit (OSHA-TWA), photochemical oxidation potential, global warming potential, ozone depletion potential, acidification potential, emission to urban air (carcinogenic and noncarcinogenic), emission to continental rural air (carcinogenic and noncarcinogenic), emission to continental fresh water (carcinogenic and noncarcinogenic), emission to continental seawater (carcinogenic and noncarcinogenic), emission to continental natural soil (carcinogenic and noncarcinogenic), and emission to continental agricultural soil (carcinogenic and noncarcinogenic) have been modeled and analyzed. The application of the developed property models for the estimation of environment-related properties and uncertainties of the estimated property values is highlighted through an illustrative example. The developed property models provide reliable estimates of environment-related properties needed to perform process synthesis, design, and analysis of sustainable chemical processes and allow one to evaluate the effect of uncertainties of estimated property values on the calculated performance of processes giving useful insights into quality and reliability of the design of sustainable processes.

Reinforcement Learning and Dopamine in Schizophrenia: Dimensions of Symptoms or Specific Features of a Disease Group?

PubMed Central

Deserno, Lorenz; Boehme, Rebecca; Heinz, Andreas; Schlagenhauf, Florian

2013-01-01

Abnormalities in reinforcement learning are a key finding in schizophrenia and have been proposed to be linked to elevated levels of dopamine neurotransmission. Behavioral deficits in reinforcement learning and their neural correlates may contribute to the formation of clinical characteristics of schizophrenia. The ability to form predictions about future outcomes is fundamental for environmental interactions and depends on neuronal teaching signals, like reward prediction errors. While aberrant prediction errors, that encode non-salient events as surprising, have been proposed to contribute to the formation of positive symptoms, a failure to build neural representations of decision values may result in negative symptoms. Here, we review behavioral and neuroimaging research in schizophrenia and focus on studies that implemented reinforcement learning models. In addition, we discuss studies that combined reinforcement learning with measures of dopamine. Thereby, we suggest how reinforcement learning abnormalities in schizophrenia may contribute to the formation of psychotic symptoms and may interact with cognitive deficits. These ideas point toward an interplay of more rigid versus flexible control over reinforcement learning. Pronounced deficits in the flexible or model-based domain may allow for a detailed characterization of well-established cognitive deficits in schizophrenia patients based on computational models of learning. Finally, we propose a framework based on the potentially crucial contribution of dopamine to dysfunctional reinforcement learning on the level of neural networks. Future research may strongly benefit from computational modeling but also requires further methodological improvement for clinical group studies. These research tools may help to improve our understanding of disease-specific mechanisms and may help to identify clinically relevant subgroups of the heterogeneous entity schizophrenia. PMID:24391603

An Evaluation of an Attitudinal Model to Measure the Potential for Combat Effectiveness of U.S. Air Force Organizations.

DTIC Science & Technology

1982-09-01

Fight Combat Effectiveness Organizational Assessment Package Morale Combat Effectiveness Model Cohesion Leadership 20. AIISTRACT (COe/Mie do ,eae aide If...of combat readiness. The major psychosocial dimensions which contribute to combat effectiveness of a military unit (morale leadership , cohesion, and...psychosocial dimensions in the combat effectiveness model (morale, leadership , and cohesion) in addition to training, logistics, alienation, and work group

Southern Ocean biological iron cycling in the pre-whaling and present ecosystems

NASA Astrophysics Data System (ADS)

Maldonado, Maria T.; Surma, Szymon; Pakhomov, Evgeny A.

2016-11-01

This study aimed to create the first model of biological iron (Fe) cycling in the Southern Ocean food web. Two biomass mass-balanced Ecopath models were built to represent pre- and post-whaling ecosystem states (1900 and 2008). Functional group biomasses (tonnes wet weight km-2) were converted to biogenic Fe pools (kg Fe km-2) using published Fe content ranges. In both models, biogenic Fe pools and consumption in the pelagic Southern Ocean were highest for plankton and small nektonic groups. The production of plankton biomass, particularly unicellular groups, accounted for the highest annual Fe demand. Microzooplankton contributed most to biological Fe recycling, followed by carnivorous zooplankton and krill. Biological Fe recycling matched previous estimates, and, under most conditions, could entirely meet the Fe demand of bacterioplankton and phytoplankton. Iron recycling by large baleen whales was reduced 10-fold by whaling between 1900 and 2008. However, even under the 1900 scenario, the contribution of whales to biological Fe recycling was negligible compared with that of planktonic consumers. These models are a first step in examining oceanic-scale biological Fe cycling, highlighting gaps in our present knowledge and key questions for future research on the role of marine food webs in the cycling of trace elements in the sea. This article is part of the themed issue 'Biological and climatic impacts of ocean trace element chemistry'.

Southern Ocean biological iron cycling in the pre-whaling and present ecosystems.

PubMed

Maldonado, Maria T; Surma, Szymon; Pakhomov, Evgeny A

2016-11-28

This study aimed to create the first model of biological iron (Fe) cycling in the Southern Ocean food web. Two biomass mass-balanced Ecopath models were built to represent pre- and post-whaling ecosystem states (1900 and 2008). Functional group biomasses (tonnes wet weight km -2 ) were converted to biogenic Fe pools (kg Fe km -2 ) using published Fe content ranges. In both models, biogenic Fe pools and consumption in the pelagic Southern Ocean were highest for plankton and small nektonic groups. The production of plankton biomass, particularly unicellular groups, accounted for the highest annual Fe demand. Microzooplankton contributed most to biological Fe recycling, followed by carnivorous zooplankton and krill. Biological Fe recycling matched previous estimates, and, under most conditions, could entirely meet the Fe demand of bacterioplankton and phytoplankton. Iron recycling by large baleen whales was reduced 10-fold by whaling between 1900 and 2008. However, even under the 1900 scenario, the contribution of whales to biological Fe recycling was negligible compared with that of planktonic consumers. These models are a first step in examining oceanic-scale biological Fe cycling, highlighting gaps in our present knowledge and key questions for future research on the role of marine food webs in the cycling of trace elements in the sea.This article is part of the themed issue 'Biological and climatic impacts of ocean trace element chemistry'. © 2016 The Author(s).

Molecular interactions in nanocellulose assembly

NASA Astrophysics Data System (ADS)

Nishiyama, Yoshiharu

2017-12-01

The contribution of hydrogen bonds and the London dispersion force in the cohesion of cellulose is discussed in the light of the structure, spectroscopic data, empirical molecular-modelling parameters and thermodynamics data of analogue molecules. The hydrogen bond of cellulose is mainly electrostatic, and the stabilization energy in cellulose for each hydrogen bond is estimated to be between 17 and 30 kJ mol-1. On average, hydroxyl groups of cellulose form hydrogen bonds comparable to those of other simple alcohols. The London dispersion interaction may be estimated from empirical attraction terms in molecular modelling by simple integration over all components. Although this interaction extends to relatively large distances in colloidal systems, the short-range interaction is dominant for the cohesion of cellulose and is equivalent to a compression of 3 GPa. Trends of heat of vaporization of alkyl alcohols and alkanes suggests a stabilization by such hydroxyl group hydrogen bonding to be of the order of 24 kJ mol-1, whereas the London dispersion force contributes about 0.41 kJ mol-1 Da-1. The simple arithmetic sum of the energy is consistent with the experimental enthalpy of sublimation of small sugars, where the main part of the cohesive energy comes from hydrogen bonds. For cellulose, because of the reduced number of hydroxyl groups, the London dispersion force provides the main contribution to intermolecular cohesion. This article is part of a discussion meeting issue `New horizons for cellulose nanotechnology'.

Modeling Common Cause Failures of Thrusters on ISS Visiting Vehicles

NASA Technical Reports Server (NTRS)

Haught, Megan

2014-01-01

This paper discusses the methodology used to model common cause failures of thrusters on the International Space Station (ISS) Visiting Vehicles. The ISS Visiting Vehicles each have as many as 32 thrusters, whose redundancy makes them susceptible to common cause failures. The Global Alpha Model (as described in NUREG/CR-5485) can be used to represent the system common cause contribution, but NUREG/CR-5496 supplies global alpha parameters for groups only up to size six. Because of the large number of redundant thrusters on each vehicle, regression is used to determine parameter values for groups of size larger than six. An additional challenge is that Visiting Vehicle thruster failures must occur in specific combinations in order to fail the propulsion system; not all failure groups of a certain size are critical.

Auditory-evoked cortical activity: contribution of brain noise, phase locking, and spectral power

PubMed Central

Harris, Kelly C.; Vaden, Kenneth I.; Dubno, Judy R.

2017-01-01

Background The N1-P2 is an obligatory cortical response that can reflect the representation of spectral and temporal characteristics of an auditory stimulus. Traditionally, mean amplitudes and latencies of the prominent peaks in the averaged response are compared across experimental conditions. Analyses of the peaks in the averaged response only reflect a subset of the data contained within the electroencephalogram (EEG) signal. We used single-trial analyses techniques to identify the contribution of brain noise, neural synchrony, and spectral power to the generation of P2 amplitude and how these variables may change across age group. This information is important for appropriate interpretation of event-related potentials (ERPs) results and in understanding of age-related neural pathologies. Methods EEG was measured from 25 younger and 25 older normal hearing adults. Age-related and individual differences in P2 response amplitudes, and variability in brain noise, phase locking value (PLV), and spectral power (4–8 Hz) were assessed from electrode FCz. Model testing and linear regression were used to determine the extent to which brain noise, PLV, and spectral power uniquely predicted P2 amplitudes and varied by age group. Results Younger adults had significantly larger P2 amplitudes, PLV, and power compared to older adults. Brain noise did not differ between age groups. The results of regression testing revealed that brain noise and PLV, but not spectral power were unique predictors of P2 amplitudes. Model fit was significantly better in younger than in older adults. Conclusions ERP analyses are intended to provide a better understanding of the underlying neural mechanisms that contribute to individual and group differences in behavior. The current results support that age-related declines in neural synchrony contribute to smaller P2 amplitudes in older normal hearing adults. Based on our results, we discuss potential models in which differences in neural synchrony and brain noise can account for associations with P2 amplitudes and behavior and potentially provide a better explanation of the neural mechanisms that underlie declines in auditory processing and training benefits. PMID:25046314

Urban women's informal savings and credit systems in Zambia.

PubMed

O'reilly, C

1996-05-01

This article is based on findings from semi-structured interviews and discussions among "chilimba" groups in Zambia. Chilimba groups are primarily women's groups that engage in credit and savings programs. Group membership ranges from 4 to 20 members. The women agree on a fixed, regular cash contribution that is given in turn to each member in a specified order. Market groups tend to be larger and contributions of about a dollar are made daily. Smaller groups tend to make larger, but less frequent contributions. Default is rare, as the commitment is taken very seriously. New members are added at the end of the rotation. Loans can be used for domestic or business use. Chilimba groups are evidence that very poor people desire savings. Chilimba brings together people with similar financial needs and resources. Chilimba does not require formal, written procedures or formal institutional frameworks. Chilimba is not a remedy for reducing overall poverty. It is appropriate only for people with some regular source of income. It does not serve as a safety net in emergencies. Long-term loans are not possible. A limitation is its openness and lack of structure that permit potential abuse. It is a livelihood strategy for women, but benefits could be gained from including men. It is urged that groups consider whether the position of the poor is being enhanced or undermined. Different models need to be tested. Members themselves must decide on the type and phasing of activities.

The large soybean (Glycine max) WRKY TF family expanded by segmental duplication events and subsequent divergent selection among subgroups.

PubMed

Yin, Guangjun; Xu, Hongliang; Xiao, Shuyang; Qin, Yajuan; Li, Yaxuan; Yan, Yueming; Hu, Yingkao

2013-10-03

WRKY genes encode one of the most abundant groups of transcription factors in higher plants, and its members regulate important biological process such as growth, development, and responses to biotic and abiotic stresses. Although the soybean genome sequence has been published, functional studies on soybean genes still lag behind those of other species. We identified a total of 133 WRKY members in the soybean genome. According to structural features of their encoded proteins and to the phylogenetic tree, the soybean WRKY family could be classified into three groups (groups I, II, and III). A majority of WRKY genes (76.7%; 102 of 133) were segmentally duplicated and 13.5% (18 of 133) of the genes were tandemly duplicated. This pattern was not apparent in Arabidopsis or rice. The transcriptome atlas revealed notable differential expression in either transcript abundance or in expression patterns under normal growth conditions, which indicated wide functional divergence in this family. Furthermore, some critical amino acids were detected using DIVERGE v2.0 in specific comparisons, suggesting that these sites have contributed to functional divergence among groups or subgroups. In addition, site model and branch-site model analyses of positive Darwinian selection (PDS) showed that different selection regimes could have affected the evolution of these groups. Sites with high probabilities of having been under PDS were found in groups I, II c, II e, and III. Together, these results contribute to a detailed understanding of the molecular evolution of the WRKY gene family in soybean. In this work, all the WRKY genes, which were generated mainly through segmental duplication, were identified in the soybean genome. Moreover, differential expression and functional divergence of the duplicated WRKY genes were two major features of this family throughout their evolutionary history. Positive selection analysis revealed that the different groups have different evolutionary rates. Together, these results contribute to a detailed understanding of the molecular evolution of the WRKY gene family in soybean.

Impact of food choice on sodium intake patterns from multiple NHANES surveys.

PubMed

Dong, Zefeng; Gao, Zhifeng; McFadden, Brandon

2017-02-01

To examine how the food consumption from various food groups would impact American adults' sodium intake and whether this impact structurally changes over time, data were obtained from six-cycle National Health and Nutrition Examination Survey (NHANES) 1999-2010. Foods were categorized by the first two digits of the USDA food code. Regression models were employed to investigate the associations between the consumption of each food group and sodium intake, and whether there were changes in the associations in consecutive six cycles. Results show that the calorie consumption of oils, beverages and water, fruit juices, fruits, lamb, fruit products, and sugars and sweets had no significant impact on individuals' sodium intake, while calorie consumption of tomatoes, fish, dark-green vegetables, and crackers contributes the most to sodium intake. The contribution to sodium intake of most food groups does not change significantly over time, with the exception of salad dressing whose contribution to sodium intake increased in four consecutive years when compared to that of 1999-2000. The sodium amount contributed by one calorie consumption (sodium density) of most food was above the daily recommendation level, 1.2 mg per calorie per day. Lowering individuals' sodium intake involves either guiding individuals to consume more fruit related products or decreasing the amount of sodium in most food groups at the production or food preparation stages. Copyright © 2016 Elsevier Ltd. All rights reserved.

Annotated bibliography of structural equation modelling: technical work.

PubMed

Austin, J T; Wolfle, L M

1991-05-01

Researchers must be familiar with a variety of source literature to facilitate the informed use of structural equation modelling. Knowledge can be acquired through the study of an expanding literature found in a diverse set of publishing forums. We propose that structural equation modelling publications can be roughly classified into two groups: (a) technical and (b) substantive applications. Technical materials focus on the procedures rather than substantive conclusions derived from applications. The focus of this article is the former category; included are foundational/major contributions, minor contributions, critical and evaluative reviews, integrations, simulations and computer applications, precursor and historical material, and pedagogical textbooks. After a brief introduction, we annotate 294 articles in the technical category dating back to Sewall Wright (1921).

The Incidence Patterns Model to Estimate the Distribution of New HIV Infections in Sub-Saharan Africa: Development and Validation of a Mathematical Model.

PubMed

Bórquez, Annick; Cori, Anne; Pufall, Erica L; Kasule, Jingo; Slaymaker, Emma; Price, Alison; Elmes, Jocelyn; Zaba, Basia; Crampin, Amelia C; Kagaayi, Joseph; Lutalo, Tom; Urassa, Mark; Gregson, Simon; Hallett, Timothy B

2016-09-01

Programmatic planning in HIV requires estimates of the distribution of new HIV infections according to identifiable characteristics of individuals. In sub-Saharan Africa, robust routine data sources and historical epidemiological observations are available to inform and validate such estimates. We developed a predictive model, the Incidence Patterns Model (IPM), representing populations according to factors that have been demonstrated to be strongly associated with HIV acquisition risk: gender, marital/sexual activity status, geographic location, "key populations" based on risk behaviours (sex work, injecting drug use, and male-to-male sex), HIV and ART status within married or cohabiting unions, and circumcision status. The IPM estimates the distribution of new infections acquired by group based on these factors within a Bayesian framework accounting for regional prior information on demographic and epidemiological characteristics from trials or observational studies. We validated and trained the model against direct observations of HIV incidence by group in seven rounds of cohort data from four studies ("sites") conducted in Manicaland, Zimbabwe; Rakai, Uganda; Karonga, Malawi; and Kisesa, Tanzania. The IPM performed well, with the projections' credible intervals for the proportion of new infections per group overlapping the data's confidence intervals for all groups in all rounds of data. In terms of geographical distribution, the projections' credible intervals overlapped the confidence intervals for four out of seven rounds, which were used as proxies for administrative divisions in a country. We assessed model performance after internal training (within one site) and external training (between sites) by comparing mean posterior log-likelihoods and used the best model to estimate the distribution of HIV incidence in six countries (Gabon, Kenya, Malawi, Rwanda, Swaziland, and Zambia) in the region. We subsequently inferred the potential contribution of each group to transmission using a simple model that builds on the results from the IPM and makes further assumptions about sexual mixing patterns and transmission rates. In all countries except Swaziland, individuals in unions were the single group contributing to the largest proportion of new infections acquired (39%-77%), followed by never married women and men. Female sex workers accounted for a large proportion of new infections (5%-16%) compared to their population size. Individuals in unions were also the single largest contributor to the proportion of infections transmitted (35%-62%), followed by key populations and previously married men and women. Swaziland exhibited different incidence patterns, with never married men and women accounting for over 65% of new infections acquired and also contributing to a large proportion of infections transmitted (up to 56%). Between- and within-country variations indicated different incidence patterns in specific settings. It is possible to reliably predict the distribution of new HIV infections acquired using data routinely available in many countries in the sub-Saharan African region with a single relatively simple mathematical model. This tool would complement more specific analyses to guide resource allocation, data collection, and programme planning.

Transport methods for probing the barrier domain of lipid bilayer membranes.

PubMed Central

Xiang, T X; Chen, X; Anderson, B D

1992-01-01

Two experimental techniques have been utilized to explore the barrier properties of lecithin/decane bilayer membranes with the aim of determining the contributions of various domains within the bilayer to the overall barrier. The thickness of lecithin/decane bilayers was systematically varied by modulating the chemical potential of decane in the annulus surrounding the bilayer using different mole fractions of squalene in decane. The dependence of permeability of a model permeant (acetamide) on the thickness of the solvent-filled region of the bilayer was assessed in these bilayers to determine the contribution of this region to the overall barrier. The flux of acetamide was found to vary linearly with bilayer area with Pm = (2.9 +/- 0.3) x 10(-4) cm s-1, after correcting for diffusion through unstirred water layers. The ratio between the overall membrane permeability coefficient and that calculated for diffusion through the hydrocarbon core in membranes having maximum thickness was 0.24, suggesting that the solvent domain contributes only slightly to the overall barrier properties. Consistent with these results, the permeability of acetamide was found to be independent of bilayer thickness. The relative contributions of the bilayer interface and ordered hydrocarbon regions to the transport barrier may be evaluated qualitatively by exploring the effective chemical nature of the barrier microenvironment. This may be probed by comparing functional group contributions to transport with those obtained for partitioning between water and various model bulk solvents ranging in polarity or hydrogen-bonding potential. A novel approach is described for obtaining group contributions to transport using ionizable permeants and pH adjustment. Using this approach, bilayer permeability coefficients of p-toluic acid and p-hydroxymethyl benzoic acid were determined to be 1.1 +/- 0.2 cm s-1 and (1.6 +/- 0.4) x 10(-3) cm s-1, respectively. From these values, the -OH group contribution to bilayer transport [delta(delta G0-OH)] was found to be 3.9 kcal/mol. This result suggests that the barrier region of the bilayer does not resemble the hydrogen-bonding environment found in octanol, but is somewhat less selective (more polar) than a hydrocarbon solvent. PMID:1420875

The Community Earth System Model-Polar Climate Working Group and the status of CESM2.

NASA Astrophysics Data System (ADS)

Bailey, D. A.; Holland, M. M.; DuVivier, A. K.

2017-12-01

The Polar Climate Working Group (PCWG) is a consortium of scientists who are interested in modeling and understanding the climate in the Arctic and the Antarctic, and how polar climate processes interact with and influence climate at lower latitudes. Our members come from universities and laboratories, and our interests span all elements of polar climate, from the ocean depths to the top of the atmosphere. In addition to conducting scientific modeling experiments, we are charged with contributing to the development and maintenance of the state-of-the-art sea ice model component (CICE) used in the Community Earth System Model (CESM). A recent priority for the PCWG has been to come up with innovative ways to bring the observational and modeling communities together. This will allow for more robust validation of climate model simulations, the development and implementation of more physically-based model parameterizations, improved data assimilation capabilities, and the better use of models to design and implement field experiments. These have been informed by topical workshops and scientific visitors that we have hosted in these areas. These activities will be discussed and information on how the better integration of observations and models has influenced the new version of the CESM, which is due to be released in late 2017, will be provided. Additionally, we will address how enhanced interactions with the observational community will contribute to model developments and validation moving forward.

The epidemic of Tuberculosis on vaccinated population

NASA Astrophysics Data System (ADS)

Syahrini, Intan; Sriwahyuni; Halfiani, Vera; Meurah Yuni, Syarifah; Iskandar, Taufiq; Rasudin; Ramli, Marwan

2017-09-01

Tuberculosis is an infectious disease which has caused a large number of mortality in Indonesia. This disease is caused by Mycrobacterium tuberculosis. Besides affecting lung, this disease also affects other organs such as lymph gland, intestine, kidneys, uterus, bone, and brain. This article discusses the epidemic of tuberculosis through employing the SEIR model. Here, the population is divided into four compartments which are susceptible, exposed, infected and recovered. The susceptible population is further grouped into two which are vaccinated group and unvaccinated group. The behavior of the epidemic is investigated through analysing the equilibrium of the model. The result shows that administering vaccine to the susceptible population contributes to the reduction of the tuberculosis epidemic rate.

[Effect of moxibustion on quantity of pinealocytes and pineal HSP 70 expression in subacute aging rats].

PubMed

Liang, Xin; Zhong, Yu

2011-08-01

To study the mechanism of moxibustion in postponing the process of aging. Thirty Wistar rats were equally randomized into control, model and moxibustion groups. The subacute aging model was established by hypodermic injection of 25% D-galactose (125 mg/kg). Moxibustion was applied to bilateral "Shenshu" (GV 23) and "Pishu" (GV 20) once everyday for 6 weeks. After slicing, the pineal gland tissue was stained with HE and insitu hybridization methods respectively for detecting the quantity of pinealocytes and the expression of heat shock protein (HSP 70). Compared with the control group, both the quantity of pinealocytes and the expression of HSP 70 in the pineal gland in the model group were downregulated significantly (P < 0.001, P < 0.01). Compared with model group, the quantity of pinealocytes and of HSP 70 mRNA in the pineal gland of moxibustion group were upregulated significantly (P < 0.01, P < 0.05). Moxibustion can suppress aging induced decrease of pinealocyte number and HSP 70 expression in subacute aging rats, which may contribute to its effect in postponing aging.

Cycles of Exploration, Reflection, and Consolidation in Model-Based Learning of Genetics

NASA Astrophysics Data System (ADS)

Kim, Beaumie; Pathak, Suneeta A.; Jacobson, Michael J.; Zhang, Baohui; Gobert, Janice D.

2015-12-01

Model-based reasoning has been introduced as an authentic way of learning science, and many researchers have developed technological tools for learning with models. This paper describes how a model-based tool, BioLogica™, was used to facilitate genetics learning in secondary 3-level biology in Singapore. The research team co-designed two different pedagogical approaches with teachers, both of which involved learner-centered "exploration and reflection" with BioLogica and teacher-led "telling" or "consolidation." One group went through the stand-alone BioLogica units for all topics prior to a series of teacher-led instructions, whereas the other group was engaged in teacher-led activities after using BioLogica for each topic. Based on the results of a series of tests on genetics, the groups performed differently from what the teacher had expected. We explore how the design of the two approaches and interactions among students might have contributed to the results.

Effect of Acetyl Group on Mechanical Properties of Chitin/Chitosan Nanocrystal: A Molecular Dynamics Study

PubMed Central

Cui, Junhe; Yu, Zechuan; Lau, Denvid

2016-01-01

Chitin fiber is the load-bearing component in natural chitin-based materials. In these materials, chitin is always partially deacetylated to different levels, leading to diverse material properties. In order to understand how the acetyl group enhances the fracture resistance capability of chitin fiber, we constructed atomistic models of chitin with varied acetylation degree and analyzed the hydrogen bonding pattern, fracture, and stress-strain behavior of these models. We notice that the acetyl group can contribute to the formation of hydrogen bonds that can stabilize the crystalline structure. In addition, it is found that the specimen with a higher acetylation degree presents a greater resistance against fracture. This study describes the role of the functional group, acetyl groups, in crystalline chitin. Such information could provide preliminary understanding of nanomaterials when similar functional groups are encountered. PMID:26742033

How Do Internal and External CSR Affect Employees' Organizational Identification? A Perspective from the Group Engagement Model

PubMed Central

Hameed, Imran; Riaz, Zahid; Arain, Ghulam A.; Farooq, Omer

2016-01-01

The literature examines the impact of firms' corporate social responsibility (CSR) activities on employees' organizational identification without considering that such activities tend to have different targets. This study explores how perceived external CSR (efforts directed toward external stakeholders) and perceived internal CSR (efforts directed toward employees) activities influence employees' organizational identification. In so doing, it examines the alternative underlying mechanisms through which perceived external and internal CSR activities build employees' identification. Applying the taxonomy prescribed by the group engagement model, the study argues that the effects of perceived external and internal CSR flow through two competing mechanisms: perceived external prestige and perceived internal respect, respectively. Further, it is suggested that calling orientation (how employees see their work contributions) moderates the effects induced by these alternative forms of CSR. The model draws on survey data collected from a sample of 414 employees across five large multinationals in Pakistan. The results obtained using structural equation modeling support these hypotheses, reinforcing the notion that internal and external CSR operate through different mediating mechanisms and more interestingly employees' calling orientation moderates these relationships to a significant degree. Theoretical contributions and practical implications of results are discussed in detail. PMID:27303345

How Do Internal and External CSR Affect Employees' Organizational Identification? A Perspective from the Group Engagement Model.

PubMed

Hameed, Imran; Riaz, Zahid; Arain, Ghulam A; Farooq, Omer

2016-01-01

The literature examines the impact of firms' corporate social responsibility (CSR) activities on employees' organizational identification without considering that such activities tend to have different targets. This study explores how perceived external CSR (efforts directed toward external stakeholders) and perceived internal CSR (efforts directed toward employees) activities influence employees' organizational identification. In so doing, it examines the alternative underlying mechanisms through which perceived external and internal CSR activities build employees' identification. Applying the taxonomy prescribed by the group engagement model, the study argues that the effects of perceived external and internal CSR flow through two competing mechanisms: perceived external prestige and perceived internal respect, respectively. Further, it is suggested that calling orientation (how employees see their work contributions) moderates the effects induced by these alternative forms of CSR. The model draws on survey data collected from a sample of 414 employees across five large multinationals in Pakistan. The results obtained using structural equation modeling support these hypotheses, reinforcing the notion that internal and external CSR operate through different mediating mechanisms and more interestingly employees' calling orientation moderates these relationships to a significant degree. Theoretical contributions and practical implications of results are discussed in detail.

Timing and petroleum sources for the Lower Cretaceous Mannville Group oil sands of northern Alberta based on 4-D modeling

USGS Publications Warehouse

Higley, D.K.; Lewan, M.D.; Roberts, L.N.R.; Henry, M.

2009-01-01

The Lower Cretaceous Mannville Group oil sands of northern Alberta have an estimated 270.3 billion m3 (BCM) (1700 billion bbl) of in-place heavy oil and tar. Our study area includes oil sand accumulations and downdip areas that partially extend into the deformation zone in western Alberta. The oil sands are composed of highly biodegraded oil and tar, collectively referred to as bitumen, whose source remains controversial. This is addressed in our study with a four-dimensional (4-D) petroleum system model. The modeled primary trap for generated and migrated oil is subtle structures. A probable seal for the oil sands was a gradual updip removal of the lighter hydrocarbon fractions as migrated oil was progressively biodegraded. This is hypothetical because the modeling software did not include seals resulting from the biodegradation of oil. Although the 4-D model shows that source rocks ranging from the Devonian-Mississippian Exshaw Formation to the Lower Cretaceous Mannville Group coals and Ostracode-zone-contributed oil to Mannville Group reservoirs, source rocks in the Jurassic Fernie Group (Gordondale Member and Poker Chip A shale) were the initial and major contributors. Kinetics associated with the type IIS kerogen in Fernie Group source rocks resulted in the early generation and expulsion of oil, as early as 85 Ma and prior to the generation from the type II kerogen of deeper and older source rocks. The modeled 50% peak transformation to oil was reached about 75 Ma for the Gordondale Member and Poker Chip A shale near the west margin of the study area, and prior to onset about 65 Ma from other source rocks. This early petroleum generation from the Fernie Group source rocks resulted in large volumes of generated oil, and prior to the Laramide uplift and onset of erosion (???58 Ma), which curtailed oil generation from all source rocks. Oil generation from all source rocks ended by 40 Ma. Although the modeled study area did not include possible western contributions of generated oil to the oil sands, the amount generated by the Jurassic source rocks within the study area was 475 BCM (2990 billion bbl). Copyright ?? 2009. The American Association of Petroleum Geologists. All rights reserved.

On valuing peers: theories of learning and intercultural competence

NASA Astrophysics Data System (ADS)

Cajander, Åsa; Daniels, Mats; McDermott, Roger

2012-12-01

This paper investigates the links between the contributing student pedagogy and other forms of peer-mediated learning models, e.g. open-ended group projects and communities of practice. We find that a fundamental concern in each of these models is the attribution of value; specifically, recognition of the value of learning that is enabled by peer interaction, and the way in which value is created and assessed within a learning community. Value is also central to theories of intercultural competence. We examine the role that the concept of value plays in the development cycle of intercultural competence and relate it to its function in peer-mediated learning models. We also argue that elements of social learning theory, principally recent work on value creation in communities of practice, are very relevant to the construction and assessment of the type of activities proposed within the contributing student pedagogy. Our theoretical analysis is situated within the context of a globally distributed open-ended group project course unit and our conclusions are illustrated with reference to student practice in this environment.

Comparisons of body size, composition, and whole body bone mass between North American and South African children.

PubMed

Micklesfield, Lisa K; Norris, Shane A; Nelson, Dorothy A; Lambert, Estelle V; van der Merwe, Lize; Pettifor, John M

2007-12-01

We compared whole body BMC of 811 black, white, and mixed ancestral origin children from Detroit, MI; Johannesburg, South Africa; and Cape Town, South Africa. Our findings support the role of genetic and environmental influences in the determination of bone mass in prepubertal children. Higher bone mass and lower fracture rates have been shown in black compared with white children and adults in North America. We compared whole body BMC (WBBMC), whole body fat mass (WBFM), and whole body fat free soft tissue (WBFFST) data between three ethnic groups of children from Detroit, MI (n = 181 white, USW; n = 230 black, USB), Johannesburg, South Africa (n = 73 white, SAW; n = 263 black, SAB), and Cape Town, South Africa (n = 64 mixed ancestral origin, SAM). SAB and SAW groups were slightly older than USW and USB groups (9.5 +/- 0.3 versus 9.3 +/- 0.1 yr); however, USB and USW boys were significantly taller, were heavier, and had a higher BMI than SAM and SAB boys. USB girls were significantly taller than SAB girls and heavier than SAB and SAM girls. In South Africa and the United States, black children had a significantly higher WBBMC than white children, after adjusting for selected best predictors. After adjusting for age, weight, and height, WBBMC was significantly higher in the SAB and SAW boys than in USW and USB and in the SAM group compared with the USW and USB groups. WBFFST and WBFM made significant contributions to a best linear model for log(WBBMC), together with age, height, and ethnicity. The best model accounted for 79% of the WBBMC variance. When included separately in the model, the model containing WBFFST accounted for 76%, and the model containing WBFM accounted for 70%, of the variance in WBBMC. WBBMC is lower in children of European ancestry compared with African ancestry, irrespective of geographical location; however, South African children have significantly higher WBBMC compared with USB and USW groups, thereby acknowledging the possible contribution of environmental factors. Reasons for the significantly higher WBBMC in the children of mixed ancestral origin compared with the other groups need to be studied further.

The Evolving Contribution of Mass Spectrometry to Integrative Structural Biology

NASA Astrophysics Data System (ADS)

Faini, Marco; Stengel, Florian; Aebersold, Ruedi

2016-06-01

Protein complexes are key catalysts and regulators for the majority of cellular processes. Unveiling their assembly and structure is essential to understanding their function and mechanism of action. Although conventional structural techniques such as X-ray crystallography and NMR have solved the structure of important protein complexes, they cannot consistently deal with dynamic and heterogeneous assemblies, limiting their applications to small scale experiments. A novel methodological paradigm, integrative structural biology, aims at overcoming such limitations by combining complementary data sources into a comprehensive structural model. Recent applications have shown that a range of mass spectrometry (MS) techniques are able to generate interaction and spatial restraints (cross-linking MS) information on native complexes or to study the stoichiometry and connectivity of entire assemblies (native MS) rapidly, reliably, and from small amounts of substrate. Although these techniques by themselves do not solve structures, they do provide invaluable structural information and are thus ideally suited to contribute to integrative modeling efforts. The group of Brian Chait has made seminal contributions in the use of mass spectrometric techniques to study protein complexes. In this perspective, we honor the contributions of the Chait group and discuss concepts and milestones of integrative structural biology. We also review recent examples of integration of structural MS techniques with an emphasis on cross-linking MS. We then speculate on future MS applications that would unravel the dynamic nature of protein complexes upon diverse cellular states.

Game Theory and Social Psychology: Conformity Games

NASA Astrophysics Data System (ADS)

Alessio, Danielle; Kilgour, D. Marc

2011-11-01

Game models can contribute to understanding of how social biases and pressures to conform can lead to puzzling behaviour in social groups. A model of the psychological biases false uniqueness and false consensus is set out. The model predicts the phenomenon of pluralistic ignorance, which is well-studied in social psychology, showing how it arises as a result of the prevalence of false uniqueness and the desire to conform. An efficient method is developed for finding Nash equilibria of the model under certain restrictions.

Spectral Models of Kuiper Belt Objects and Centaurs

NASA Technical Reports Server (NTRS)

Cruikshank, Dale; Ore, Christina M. Dalle

2003-01-01

We present models of the spectral reflectances of groups of outer Solar System objects defined primarily by their colors in the spectral region 0.4 -1.2 microns, and which have geometric albedo 0.04 at wavelength 0.55 microns. Our models of the groups with the strongest reflectance gradients (reddest colors) use combinations of organic tholins. We test the hypothesis that metal-reddened igneous rock-forming minerals contribute to the red colors of Centaurs and KBOs by using the space-weathered lunar soil as one of the components of our models. We find that our models can admit the presence of moderate amounts of space-weathered (metal-reddened) minerals, but that they do not require this material to achieve the red colors of the reddest outer Solar System bodies. Our models with organic tholins are consistent with the results of other investigators.

Learning Democratic Global Governance.

ERIC Educational Resources Information Center

Haavelsrud, Magnus

1996-01-01

Outlines a model process of developing knowledge from within different groups and cultures to allow more equitable participation of all world societies in the definition of global governance. Reviews concepts relevant to education's contributions toward learning and creating democratic global governance. Discusses the educational utility of…

Genetic affinities of the Siddis of South India: an emigrant population of East Africa.

PubMed

Gauniyal, Mansi; Chahal, S M S; Kshatriya, Gautam K

2008-06-01

Historical records indicate that the Portuguese brought the African Siddis to Goa, India, as slaves about 500 years ago. Subsequently, the Siddis moved into the interior regions of the state of Karnataka, India, and have remained there ever since. Over time the Siddis have experienced considerable cultural changes because of their proximity to neighboring population groups. To understand the biological consequences of these changes, we studied the Siddis to determine the extent of genetic variation and the contributions from the African, European, and Indian ancestral populations. In the present study we typed the Siddis for 20 polymorphic serological, red cell, and Alu insertion-deletion loci. The overall pattern of phenotype (and genotype) distribution is in accordance with Hardy-Weinberg expectations. Considering the ethnohistorical records and the availability of secondary-source genetic data, we used two data sets in the analysis: one comprising eight serological and red cell enzyme markers with eight population groups and another comprising six Alu insertion-deletion markers with seven tribal groups of South India. The dendrograms generated from these two data sets on the basis of genetic distance analysis between the selected populations of African, European, and Indian descent reveals that the Siddis are closer to the Africans than they are to the South Indian populations. Genetic admixture analysis using a dihybrid model (19 loci) and a trihybrid model (10 loci and 8 loci) shows that the predominant influence comes from the Africans, a lesser contribution from the South Indians, and a slight contribution from the Portuguese. Thus the original composition of the African genes among the Siddis has been diluted to some extent by the contribution from southern Indian population groups. There is no nonrandom association of alleles among a set of 10 genetic marker systems considered in the present study. The demonstration of genetic homogeneity of the Siddis, despite their admixed origin, suggests the utility of this population for genetic and epidemiological studies.

Mechanism Design for Incentivizing Social Media Contributions

NASA Astrophysics Data System (ADS)

Singh, Vivek K.; Jain, Ramesh; Kankanhalli, Mohan

Despite recent advancements in user-driven social media platforms, tools for studying user behavior patterns and motivations remain primitive. We highlight the voluntary nature of user contributions and that users can choose when (and when not) to contribute to the common media pool. A Game theoretic framework is proposed to study the dynamics of social media networks where contribution costs are individual but gains are common. We model users as rational selfish agents, and consider domain attributes like voluntary participation, virtual reward structure, network effect, and public-sharing to model the dynamics of this interaction. The created model describes the most appropriate contribution strategy from each user's perspective and also highlights issues like 'free-rider' problem and individual rationality leading to irrational (i.e. sub-optimal) group behavior. We also consider the perspective of the system designer who is interested in finding the best incentive mechanisms to influence the selfish end-users so that the overall system utility is maximized. We propose and compare multiple mechanisms (based on optimal bonus payment, social incentive leveraging, and second price auction) to study how a system designer can exploit the selfishness of its users, to design incentive mechanisms which improve the overall task-completion probability and system performance, while possibly still benefiting the individual users.

Using an experimental model for the study of therapeutic touch.

PubMed

dos Santos, Daniella Soares; Marta, Ilda Estéfani Ribeiro; Cárnio, Evelin Capellari; de Quadros, Andreza Urba; Cunha, Thiago Mattar; de Carvalho, Emilia Campos

2013-02-01

to verify whether the Paw Edema Model can be used in investigations about the effects of Therapeutic Touch on inflammation by measuring the variables pain, edema and neutrophil migration. this is a pilot and experimental study, involving ten male mice of the same genetic strain and divided into experimental and control group, submitted to the chemical induction of local inflammation in the right back paw. The experimental group received a daily administration of Therapeutic Touch for 15 minutes during three days. the data showed statistically significant differences in the nociceptive threshold and in the paw circumference of the animals from the experimental group on the second day of the experiment. the experiment model involving animals can contribute to study the effects of Therapeutic Touch on inflammation, and adjustments are suggested in the treatment duration, number of sessions and experiment duration.

Modeling Common Cause Failures of Thrusters on ISS Visiting Vehicles

NASA Technical Reports Server (NTRS)

Haught, Megan; Duncan, Gary

2014-01-01

This paper discusses the methodology used to model common cause failures of thrusters on the International Space Station (ISS) Visiting Vehicles. The ISS Visiting Vehicles each have as many as 32 thrusters, whose redundancy and similar design make them susceptible to common cause failures. The Global Alpha Model (as described in NUREG/CR-5485) can be used to represent the system common cause contribution, but NUREG/CR-5496 supplies global alpha parameters for groups only up to size six. Because of the large number of redundant thrusters on each vehicle, regression is used to determine parameter values for groups of size larger than six. An additional challenge is that Visiting Vehicle thruster failures must occur in specific combinations in order to fail the propulsion system; not all failure groups of a certain size are critical.

The Group-lending Model and Social Closure: Microcredit, Exclusion, and Health in Bangladesh

PubMed Central

Johnston, Heidi Bart

2009-01-01

According to social exclusion theory, health risks are positively associated with involuntary social, economic, political and cultural exclusion from society. In this paper, a social exclusion framework has been used, and available literature on microcredit in Bangladesh has been reviewed to explore the available evidence on associations among microcredit, exclusion, and health outcomes. The paper addresses the question of whether participation in group-lending reduces health inequities through promoting social inclusion. The group-lending model of microcredit is a development intervention in which small-scale credit for income-generation activities is provided to groups of individuals who do not have material collateral. The paper outlines four pathways through which microcredit can affect health status: financing care in the event of health emergencies; financing health inputs such as improved nutrition; as a platform for health education; and by increasing social capital through group meetings and mutual support. For many participants, the group-lending model of microcredit can mitigate exclusionary processes and lead to improvements in health for some; for others, it can worsen exclusionary processes which contribute to health disadvantage. PMID:19761085

The group-lending model and social closure: microcredit, exclusion, and health in Bangladesh.

PubMed

Schurmann, Anna T; Johnston, Heidi Bart

2009-08-01

According to social exclusion theory, health risks are positively associated with involuntary social, economic, political and cultural exclusion from society. In this paper, a social exclusion framework has been used, and available literature on microcredit in Bangladesh has been reviewed to explore the available evidence on associations among microcredit, exclusion, and health outcomes. The paper addresses the question of whether participation in group-lending reduces health inequities through promoting social inclusion. The group-lending model of microcredit is a development intervention in which small-scale credit for income-generation activities is provided to groups of individuals who do not have material collateral. The paper outlines four pathways through which microcredit can affect health status: financing care in the event of health emergencies; financing health inputs such as improved nutrition; as a platform for health education; and by increasing social capital through group meetings and mutual support. For many participants, the group-lending model of microcredit can mitigate exclusionary processes and lead to improvements in health for some; for others, it can worsen exclusionary processes which contribute to health disadvantage.

Improved estimation of sediment source contributions by concentration-dependent Bayesian isotopic mixing model

NASA Astrophysics Data System (ADS)

Ram Upadhayay, Hari; Bodé, Samuel; Griepentrog, Marco; Bajracharya, Roshan Man; Blake, Will; Cornelis, Wim; Boeckx, Pascal

2017-04-01

The implementation of compound-specific stable isotope (CSSI) analyses of biotracers (e.g. fatty acids, FAs) as constraints on sediment-source contributions has become increasingly relevant to understand the origin of sediments in catchments. The CSSI fingerprinting of sediment utilizes CSSI signature of biotracer as input in an isotopic mixing model (IMM) to apportion source soil contributions. So far source studies relied on the linear mixing assumptions of CSSI signature of sources to the sediment without accounting for potential effects of source biotracer concentration. Here we evaluated the effect of FAs concentration in sources on the accuracy of source contribution estimations in artificial soil mixture of three well-separated land use sources. Soil samples from land use sources were mixed to create three groups of artificial mixture with known source contributions. Sources and artificial mixture were analysed for δ13C of FAs using gas chromatography-combustion-isotope ratio mass spectrometry. The source contributions to the mixture were estimated using with and without concentration-dependent MixSIAR, a Bayesian isotopic mixing model. The concentration-dependent MixSIAR provided the closest estimates to the known artificial mixture source contributions (mean absolute error, MAE = 10.9%, and standard error, SE = 1.4%). In contrast, the concentration-independent MixSIAR with post mixing correction of tracer proportions based on aggregated concentration of FAs of sources biased the source contributions (MAE = 22.0%, SE = 3.4%). This study highlights the importance of accounting the potential effect of a source FA concentration for isotopic mixing in sediments that adds realisms to mixing model and allows more accurate estimates of contributions of sources to the mixture. The potential influence of FA concentration on CSSI signature of sediments is an important underlying factor that determines whether the isotopic signature of a given source is observable even after equilibrium. Therefore inclusion of FA concentrations of the sources in the IMM formulation is standard procedure for accurate estimation of source contributions. The post model correction approach that dominates the CSSI fingerprinting causes bias, especially if the FAs concentration of sources differs substantially.

Collective Action Problem in Heterogeneous Groups with Punishment and Foresight

NASA Astrophysics Data System (ADS)

Perry, Logan; Shrestha, Mahendra Duwal; Vose, Michael D.; Gavrilets, Sergey

2018-03-01

The collective action problem can easily undermine cooperation in groups. Recent work has shown that within-group heterogeneity can under some conditions promote voluntary provisioning of collective goods. Here we generalize this work for the case when individuals can not only contribute to the production of collective goods, but also punish free-riders. To do this, we extend the standard theory by allowing individuals to have limited foresight so they can anticipate actions of their group-mates. For humans, this is a realistic assumption because we possess a "theory of mind". We use agent-based simulations to study collective actions that aim to overcome challenges from nature or win competition with neighboring groups. We contrast the dynamics of collective action in egalitarian and hierarchical groups. We show that foresight allows groups to overcome both the first- and second-order free-rider problems. While foresight increases cooperation, it does not necessarily result in higher payoffs. We show that while between-group conflicts promotes within-group cooperation, the effects of cultural group selection on cooperation are relatively small. Our models predict the emergence of a division of labor in which more powerful individuals specialize in punishment while less powerful individuals mostly contribute to the production of collective goods.

D-term contributions and CEDM constraints in E6 × SU(2)F × U(1)A SUSY GUT model

NASA Astrophysics Data System (ADS)

Shigekami, Yoshihiro

2017-11-01

We focus on E6 × SU(2)F × U(1)A supersymmetric (SUSY) grand unified theory (GUT) model. In this model, realistic Yukawa hierarchies and mixings are realized by introducing all allowed interactions with 𝓞(1) coefficients. Moreover, we can take stop mass is smaller than the other sfermion masses. This type of spectrum called by natural SUSY type sfermion mass spectrum can suppress the SUSY contributions to flavor changing neutral current (FCNC) and stabilize weak scale at the same time. However, light stop predicts large up quark CEDM and stop contributions are not decoupled. Since there is Kobayashi-Maskawa phase, stop contributions to the up quark CEDM is severely constrained even if all SUSY breaking parameters and Higgsino mass parameter μ are real. In this model, real up Yukawa couplings are realized at the GUT scale because of spontaneous CP violation. Therefore CEDM bounds are satisfied, although up Yukawa couplings are complex at the SUSY scale through the renormalization equation group effects. We calculated the CEDMs and found that EDM constraints can be satisfied even if stop mass is 𝓞(1) TeV. In addition, we investigate the size of D-terms in this model. Since these D-term contributions is flavor dependent, the degeneracy of sfermion mass spectrum is destroyed and the size of D-term is strongly constrained by FCNCs when SUSY breaking scale is the weak scale. However, SUSY breaking scale is larger than 1 TeV in order to obtain 125 GeV Higgs mass, and therefore sizable D-term contribution is allowed. Furthermore, we obtained the non-trivial prediction for the difference of squared sfermion mass.

Evolution of Precipitation Particle Size Distributions within MC3E Systems and its Impact on Aerosol-Cloud-Precipitation Interactions: Final Report

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

Kollias, Pavlos

2017-08-08

This is a multi-institutional, collaborative project using observations and modeling to study the evolution (e.g. formation and growth) of hydrometeors in continental convective clouds. Our contribution was in data analysis for the generation of high-value cloud and precipitation products and derive cloud statistics for model validation. There are two areas in data analysis that we contributed: i) the development of novel, state-of-the-art dual-wavelength radar algorithms for the retrieval of cloud microphysical properties and ii) the evaluation of large domain, high-resolution models using comprehensive multi-sensor observations. Our research group developed statistical summaries from numerous sensors and developed retrievals of vertical airmore » motion in deep convection.« less

Developing entrepreneurial competencies for successful business model canvas

NASA Astrophysics Data System (ADS)

Sundah, D. I. E.; Langi, C.; Maramis, D. R. S.; Tawalujan, L. dan

2018-01-01

We explore the competencies of entrepreneurship that contribute to business model canvas. This research conducted at smoked fish industries in Province of North Sulawesi, Indonesia. This research used a mixed method which integrating both quantitative and qualitative approaches in a sequential design. The technique of snowball sampling and questionnaire has been used in collecting data from 44 entrepreneurs. Structural equation modeling with SmartPLS application program has been used in analyzing this data to determine the effect of entrepreneurial competencies on business model canvas. We also investigate 3 entrepreneurs who conducted smoked fish business and analyzed their business by using business model canvas. Focus Group Discussion is used in collecting data from 2 groups of entrepreneurs from 2 different locations. The empirical results show that entrepreneurial competencies which consists of managerial competencies, technical competencies, marketing competencies, financial competencies, human relations competencies, and the specific working attitude of entrepreneur has a positive and significantly effect on business model canvas. Additionally, the empirical cases and discussion with 2 groups of entrepreneurs support the quantitative result and it found that human relations competencies have greater influence in achieving successful business model canvas.

Protonation of Different Goethite Surfaces - Unified Models for NaNO3 and NaCl Media.

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

Lutzenkirchen, Johannes; Boily, Jean F.; Gunneriusson, Lars

2008-01-01

Acid-base titration data for two goethites samples in sodium nitrate and sodium chloride media are discussed. The data are modelled based on various surface complexation models in the framework of the MUlti SIte Complexation (MUSIC) model. Various assumptions with respect to the goethite morphology are considered in determining the site density of the surface functional groups. The results from the various model applications are not statistically significant in terms of goodness of fit. More importantly, various published assumptions with respect to the goethite morphology (i.e. the contributions of different crystal planes and their repercussions on the “overall” site densities ofmore » the various surface functional groups) do not significantly affect the final model parameters. The simultaneous fit of the chloride and nitrate data results in electrolyte binding constants, which are applicable over a wide range of electrolyte concentrations including mixtures of chloride and nitrate. Model parameters for the high surface area goethite sample are in excellent agreement with parameters that were independently obtained by another group on different goethite titration data sets.« less

The contribution of perceived parental support to the career self-efficacy of deaf, hard-of-hearing, and hearing adolescents.

PubMed

Michael, Rinat; Most, Tova; Cinamon, Rachel Gali

2013-01-01

The current study examined the contribution of different types of parental support to career self-efficacy among 11th and 12th grade students (N = 160): 66 students with hearing loss (23 hard of hearing and 43 deaf) and 94 hearing students. Participants completed the Career-Related Parent Support Scale, the Career Decision-Making Self-Efficacy Scale, and the Self-Efficacy for the Management of Work-Family Conflict questionnaire. Different aspects of parental support predicted different types of career self-efficacies across the 3 groups. Differences among groups were also found when levels of parental support were compared. The deaf group perceived lower levels of parental career-related modeling and verbal encouragement in comparison with the hard-of-hearing students and higher levels of parental emotional support compared with the hearing participants. No significant differences were found among the research groups in career decision-making self-efficacy and self-efficacy in managing work-family conflict. Implications for theory and practice are discussed.

The contribution of an animal model toward uncovering biological risk factors for PTSD.

PubMed

Cohen, Hagit; Matar, Michael A; Richter-Levin, Gal; Zohar, Joseph

2006-07-01

Clinical studies of posttraumatic stress disorder (PTSD) have elicited proposed risk factors for developing PTSD in the aftermath of stress exposure. Generally, these risk factors have arisen from retrospective analysis of premorbid characteristics of study populations. A valid animal model of PTSD can complement clinical studies and help to elucidate issues, such as the contribution of proposed risk factors, in ways which are not practicable in the clinical arena. Important qualities of animal models include the possibility to conduct controlled prospective studies, easy access to postmortem brains, and the availability of genetically manipulated subjects, which can be tailored to specific needs. When these qualities are further complemented by an approach which defines phenomenologic criteria to address the variance in individual response pattern and magnitude, enabling the animal subjects to be classified into definable groups for focused study, the model acquires added validity. This article presents an overview of a series of studies in such an animal model which examine the contribution of two proposed risk factors and the value of two early postexposure pharmacological manipulations on the prevalence rates of subjects displaying an extreme magnitude of behavioral response to a predator stress paradigm.

Photochemical grid model implementation and application of VOC, NOx, and O3 source apportionment

EPA Science Inventory

For the purposes of developing optimal emissions control strategies, efficient approaches are needed to identify the major sources or groups of sources that contribute to elevated ozone (O3) concentrations. Source-based apportionment techniques implemented in photochemical grid m...

Contribution of ethnic group and socioeconomic status to degree of disability in rheumatoid arthritis in Chilean patients.

PubMed

Alarcón, Ana M; Muñoz, Sergio; Kaufman, Jay S; Martínez, Carlos; Riedemann, Pablo; Kaliski, Sonia

2015-04-01

The aim of this study was to estimate the contributions of ethnic group and socioeconomic status as social determinants related to disability and disease activity in Chilean Mapuche and non-Mapuche patients with rheumatoid arthritis (RA). Descriptive cross-sectional study with a stratified hospital-based sample of 189 patients in treatment with disease-modifying anti-rheumatic drugs. We assessed disability as categorical variable with the Health Assessment Questionnaire, disease activity with the Disease Activity Score instrument, and socioeconomic status with a standard questionnaire used by the Chilean government. Measures of association, stratified analyses and a multiple logistic regression model were used to analyze the data using the Stata 12.1 software package. Low socioeconomic status (annual income below US$ 7,200) is associated with disability (OR 3.87 CI 1.68-9.20) and Mapuche ethnic identity also contributes to disability (OR 2.48, CI 1.09-5.89). Relevant but not statistically significant in multivariable models were variables such as age, gender and place of residence. RA patients with a low socioeconomic status have almost three times the odds of having a moderate to high disability, independent of their ethnic group, gender or place of residence. Therefore, healthcare efforts should be aimed at promoting early diagnosis and prompt treatment among populations with high levels of poverty, which in the region of the Araucanía means primarily indigenous rural areas.

Translating evidence into practice: Hong Kong Reference Framework for Preventive Care for Children in Primary Care Settings.

PubMed

Siu, Natalie P Y; Too, L C; Tsang, Caroline S H; Young, Betty W Y

2015-06-01

There is increasing evidence that supports the close relationship between childhood and adult health. Fostering healthy growth and development of children deserves attention and effort. The Reference Framework for Preventive Care for Children in Primary Care Settings has been published by the Task Force on Conceptual Model and Preventive Protocols under the direction of the Working Group on Primary Care. It aims to promote health and prevent disease in children and is based on the latest research, and contributions of the Clinical Advisory Group that comprises primary care physicians, paediatricians, allied health professionals, and patient groups. This article highlights the comprehensive, continuing, and patient-centred preventive care for children and discusses how primary care physicians can incorporate the evidence-based recommendations into clinical practice. It is anticipated that the adoption of this framework will contribute to improved health and wellbeing of children.

How Knowledge Worker Teams Deal Effectively with Task Uncertainty: The Impact of Transformational Leadership and Group Development.

PubMed

Leuteritz, Jan-Paul; Navarro, José; Berger, Rita

2017-01-01

The purpose of this paper is to clarify how leadership is able to improve team effectiveness, by means of its influence on group processes (i.e., increasing group development) and on the group task (i.e., decreasing task uncertainty). Four hundred and eight members of 107 teams in a German research and development (R&D) organization completed a web-based survey; they provided measures of transformational leadership, group development, 2 aspects of task uncertainty, task interdependence, and team effectiveness. In 54 of these teams, the leaders answered a web-based survey on team effectiveness. We tested the model with the data from team members, using structural equations modeling. Group development and a task uncertainty measurement that refers to unstable demands from outside the team partially mediate the effect of transformational leadership on team effectiveness in R&D organizations ( p < 0.05). Although transformational leaders reduce unclarity of goals ( p < 0.05), this seems not to contribute to team effectiveness. The data provided by the leaders was used to assess common source bias, which did not affect the interpretability of the results. Limitations include cross-sectional data and a lower than expected variance of task uncertainty across different job types. This paper contributes to understanding how knowledge worker teams deal effectively with task uncertainty and confirms the importance of group development in this context. This is the first study to examine the effects of transformational leadership and team processes on team effectiveness considering the task characteristics uncertainty and interdependence.

How Knowledge Worker Teams Deal Effectively with Task Uncertainty: The Impact of Transformational Leadership and Group Development

PubMed Central

Leuteritz, Jan-Paul; Navarro, José; Berger, Rita

2017-01-01

The purpose of this paper is to clarify how leadership is able to improve team effectiveness, by means of its influence on group processes (i.e., increasing group development) and on the group task (i.e., decreasing task uncertainty). Four hundred and eight members of 107 teams in a German research and development (R&D) organization completed a web-based survey; they provided measures of transformational leadership, group development, 2 aspects of task uncertainty, task interdependence, and team effectiveness. In 54 of these teams, the leaders answered a web-based survey on team effectiveness. We tested the model with the data from team members, using structural equations modeling. Group development and a task uncertainty measurement that refers to unstable demands from outside the team partially mediate the effect of transformational leadership on team effectiveness in R&D organizations (p < 0.05). Although transformational leaders reduce unclarity of goals (p < 0.05), this seems not to contribute to team effectiveness. The data provided by the leaders was used to assess common source bias, which did not affect the interpretability of the results. Limitations include cross-sectional data and a lower than expected variance of task uncertainty across different job types. This paper contributes to understanding how knowledge worker teams deal effectively with task uncertainty and confirms the importance of group development in this context. This is the first study to examine the effects of transformational leadership and team processes on team effectiveness considering the task characteristics uncertainty and interdependence. PMID:28861012

The Economic Organization of Extended Family Households by Race/Ethnicity and Socioeconomic Status.

PubMed

Reyes, Adriana M

2018-02-01

This study examines differences in the amount of economic support or mutual benefit derived from extended family living arrangements by studying differences in monetary contributions to essential household expenditures across family units in extended family households. Using the 2008 Survey of Income and Program Participation, multivariate regression and selection models are estimated to assess racial differences in family contributions toward household expenses in extended family households. Extended family households have very unequal monetary contributions towards household rent and utilities, although Hispanics have less unequal monetary contributions compared to other racial groups. Hispanic and Asians extended family households experience decreasing inequality in financial contributions as the income of each family increases whereas no relationship between financial contributions and income is found for whites or blacks. This suggests a different cultural orientation to extended family living arrangements for Asians and Hispanics compared to non-Hispanic whites.

Preventing penetrating hand injuries in sabre fencing: an application and critique of the van Mechelen model by the Fédération Internationale d'Escrime.

PubMed

Harmer, Peter A

2015-09-01

To address the unusual phenomenon of unbroken blades causing penetrating hand injuries in sabre fencing by applying the van Mechelen model of the 'sequence of prevention'. Cases were collected from three surveillance systems and snowball sampling, and examined for potential aetiological factors. Presumed contributing factors were evaluated against the available evidence to compile a viable list for change. Determining a prevention strategy was guided by the philosophy of developing an approach that was most likely to produce a meaningful reduction in these injuries with the least disruption to the current norms of competitive sabre fencing. Nine factors which contributed, either individually or in some combination, to these injuries were grouped under three headings relating to: (1) the nature of modern sabre fencing, (2) the design of the sabre blade and (3) the vulnerability of the hand. Changes to the design and integrity of sabre gloves were selected as the most feasible option and new standards were introduced as compulsory in international competitions from 1 April 2014. The effect of this change is now being monitored via available surveillance systems. The van Mechelen model is a useful framework for sports federations to apply to reduce injury risk, even for rare injuries. However, this research model has limitations in guiding the realities of sometimes competing interests among the scientific, political, financial and technical aspects of injury prevention interventions. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

COMPARING THE IMPAIRMENT PROFILES OF OLDER DRIVERS AND NON-DRIVERS: TOWARD THE DEVELOPMENT OF A FITNESS-TO-DRIVE MODEL

PubMed Central

Antin, Jonathan F.; Stanley, Laura M.; Guo, Feng

2011-01-01

The purpose of this research effort was to compare older driver and non-driver functional impairment profiles across some 60 assessment metrics in an initial effort to contribute to the development of fitness-to-drive assessment models. Of the metrics evaluated, 21 showed statistically significant differences, almost all favoring the drivers. Also, it was shown that a logistic regression model comprised of five of the assessment scores could completely and accurately separate the two groups. The results of this study imply that older drivers are far less functionally impaired than non-drivers of similar ages, and that a parsimonious model can accurately assign individuals to either group. With such models, any driver classified or diagnosed as a non-driver would be a strong candidate for further investigation and intervention. PMID:22058607

Fostering marginalized youths' political participation: longitudinal roles of parental political socialization and youth sociopolitical development.

PubMed

Diemer, Matthew A

2012-09-01

This study examines the roles of parental political socialization and the moral commitment to change social inequalities in predicting marginalized youths' (defined here as lower-SES youth of color) political participation. These issues are examined by applying structural equation modeling to a longitudinal panel of youth. Because tests of measurement invariance suggested racial/ethnic heterogeneity, the structural model was fit separately for three racial/ethnic groups. For each group, parental political socialization: discussion predicted youths' commitment to produce social change and for two groups, longitudinally predicted political participation. This study contributes to the literature by examining civic/political participation among disparate racial/ethnic groups, addresses an open scholarly question (whether youths' commitment to create social change predicts their "traditional" participation), and emphasizes parents' role in fostering marginalized youths' civic and political participation.

The Incidence Patterns Model to Estimate the Distribution of New HIV Infections in Sub-Saharan Africa: Development and Validation of a Mathematical Model

PubMed Central

Cori, Anne; Pufall, Erica L.; Price, Alison; Elmes, Jocelyn; Zaba, Basia; Crampin, Amelia C.; Lutalo, Tom; Gregson, Simon; Hallett, Timothy B.

2016-01-01

Background Programmatic planning in HIV requires estimates of the distribution of new HIV infections according to identifiable characteristics of individuals. In sub-Saharan Africa, robust routine data sources and historical epidemiological observations are available to inform and validate such estimates. Methods and Findings We developed a predictive model, the Incidence Patterns Model (IPM), representing populations according to factors that have been demonstrated to be strongly associated with HIV acquisition risk: gender, marital/sexual activity status, geographic location, “key populations” based on risk behaviours (sex work, injecting drug use, and male-to-male sex), HIV and ART status within married or cohabiting unions, and circumcision status. The IPM estimates the distribution of new infections acquired by group based on these factors within a Bayesian framework accounting for regional prior information on demographic and epidemiological characteristics from trials or observational studies. We validated and trained the model against direct observations of HIV incidence by group in seven rounds of cohort data from four studies (“sites”) conducted in Manicaland, Zimbabwe; Rakai, Uganda; Karonga, Malawi; and Kisesa, Tanzania. The IPM performed well, with the projections’ credible intervals for the proportion of new infections per group overlapping the data’s confidence intervals for all groups in all rounds of data. In terms of geographical distribution, the projections’ credible intervals overlapped the confidence intervals for four out of seven rounds, which were used as proxies for administrative divisions in a country. We assessed model performance after internal training (within one site) and external training (between sites) by comparing mean posterior log-likelihoods and used the best model to estimate the distribution of HIV incidence in six countries (Gabon, Kenya, Malawi, Rwanda, Swaziland, and Zambia) in the region. We subsequently inferred the potential contribution of each group to transmission using a simple model that builds on the results from the IPM and makes further assumptions about sexual mixing patterns and transmission rates. In all countries except Swaziland, individuals in unions were the single group contributing to the largest proportion of new infections acquired (39%–77%), followed by never married women and men. Female sex workers accounted for a large proportion of new infections (5%–16%) compared to their population size. Individuals in unions were also the single largest contributor to the proportion of infections transmitted (35%–62%), followed by key populations and previously married men and women. Swaziland exhibited different incidence patterns, with never married men and women accounting for over 65% of new infections acquired and also contributing to a large proportion of infections transmitted (up to 56%). Between- and within-country variations indicated different incidence patterns in specific settings. Conclusions It is possible to reliably predict the distribution of new HIV infections acquired using data routinely available in many countries in the sub-Saharan African region with a single relatively simple mathematical model. This tool would complement more specific analyses to guide resource allocation, data collection, and programme planning. PMID:27622516

Reducing social inequalities in health: work-related strategies.

PubMed

Siegrist, Johannes

2002-01-01

Despite reduced health risks in terms of physical and chemical hazards current trends in occupational life continue to contribute to ill health and disease among economically active people. Stress at work plays a crucial role in this respect, as evidenced by recent scientific progress. This paper discusses two leading theoretical models of work-related stress, the demand-control model and the model of effort-reward imbalance, and it summarizes available evidence on adverse health effects. As work stress in terms of these models is more prevalent among lower socioeconomic status groups, these conditions contribute to the explanation of socially graded risks of morbidity and mortality in midlife. Implications of this new knowledge for the design and implementation of worksite health-promotion measures are elaborated. In conclusion, it is argued that workplace strategies deserve high priority on any agenda that aims at reducing social inequalities in health.

Uncertainty Propagation Methods for High-Dimensional Complex Systems

NASA Astrophysics Data System (ADS)

Mukherjee, Arpan

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

New constraints on dark matter effective theories from standard model loops.

PubMed

Crivellin, Andreas; D'Eramo, Francesco; Procura, Massimiliano

2014-05-16

We consider an effective field theory for a gauge singlet Dirac dark matter particle interacting with the standard model fields via effective operators suppressed by the scale Λ ≳ 1 TeV. We perform a systematic analysis of the leading loop contributions to spin-independent Dirac dark matter-nucleon scattering using renormalization group evolution between Λ and the low-energy scale probed by direct detection experiments. We find that electroweak interactions induce operator mixings such that operators that are naively velocity suppressed and spin dependent can actually contribute to spin-independent scattering. This allows us to put novel constraints on Wilson coefficients that were so far poorly bounded by direct detection. Constraints from current searches are already significantly stronger than LHC bounds, and will improve in the near future. Interestingly, the loop contribution we find is isospin violating even if the underlying theory is isospin conserving.

Sodium intake status in United States and potential reduction modeling: an NHANES 2007-2010 analysis.

PubMed

Agarwal, Sanjiv; Fulgoni, Victor L; Spence, Lisa; Samuel, Priscilla

2015-11-01

Limiting dietary sodium intake has been a consistent dietary recommendation. Using NHANES 2007-2010 data, we estimated current sodium intake and modeled the potential impact of a new sodium reduction technology on sodium intake. NHANES 2007-2010 data were used to assess current sodium intake. The National Cancer Institute method was used for usual intake determination. Suggested sodium reductions using SODA-LO (®) Salt Microspheres ranged from 20% to 30% in 953 foods and usual intakes were modeled by using various reduction factors and levels of market penetration. SAS 9.2, SUDAAN 11, and NHANES survey weights were used in all calculations with assessment across gender and age groups. Current (2007-2010) sodium intake (mg/day) exceeds recommendations across all age gender groups and has not changed during the last decade. However, sodium intake measured as a function of food intake (mg/g food) has decreased significantly during the last decade. Two food categories contribute about 2/3rd of total sodium intake: "Grain Products" and "Meat, Poultry, Fish & Mixtures". Sodium reduction, with 100% market penetration of the new technology, was estimated to be 230-300 mg/day or 7-9% of intake depending upon age and gender group. Sodium reduction innovations like SODA-LO (®) Salt Microspheres could contribute to meaningful reductions in sodium intake.

An original model of the northern Gulf of Mexico using Ecopath with Ecosim and its implications for the effects of fishing on ecosystem structure and maturity

NASA Astrophysics Data System (ADS)

Geers, T. M.; Pikitch, E. K.; Frisk, M. G.

2016-07-01

The Gulf of Mexico (GoM) is a valuable ecosystem both socially and economically, and fisheries contribute substantially to this value. Gulf menhaden, Brevoortia patronus, support the largest fishery in the Gulf (by weight) and provide forage for marine mammals, seabirds and commercially and recreationally important fish species. Understanding the complex interactions among multiple fisheries and myriad unfished species requires tools different from those used in traditional single-species management. One such tool, Ecopath with Ecosim (EwE) is increasingly being used to construct food web models of aquatic ecosystems and to evaluate fisheries management options within a broader, ecosystem context. Here, an EwE model was developed to examine the impact of Gulf fisheries on ecosystem structure and maturity. This model builds on previously published EwE models of the GoM, and is tailored to the range and habitat of Gulf menhaden. The model presented here consists of 47 functional groups, including 4 seabird groups, 1 marine mammal group, 3 elasmobranch groups, 26 bony fish groups, 9 invertebrate groups, 3 primary producer groups and 1 detritus group. A number of different management scenarios for Gulf fisheries were modeled and the results were evaluated in terms of impacts on ecosystem maturity and development. The results of the model simulations indicated that the northern Gulf of Mexico is in an immature state (sensuOdum, 1969). Management scenarios that increased fishing pressure over time consistently resulted in a decrease in the maturity indices. In particular, we found that Gulf menhaden, as a key forage fish in the ecosystem, plays a substantial role in the structure and functioning of the ecosystem.

A consensus reaching model for 2-tuple linguistic multiple attribute group decision making with incomplete weight information

NASA Astrophysics Data System (ADS)

Zhang, Wancheng; Xu, Yejun; Wang, Huimin

2016-01-01

The aim of this paper is to put forward a consensus reaching method for multi-attribute group decision-making (MAGDM) problems with linguistic information, in which the weight information of experts and attributes is unknown. First, some basic concepts and operational laws of 2-tuple linguistic label are introduced. Then, a grey relational analysis method and a maximising deviation method are proposed to calculate the incomplete weight information of experts and attributes respectively. To eliminate the conflict in the group, a weight-updating model is employed to derive the weights of experts based on their contribution to the consensus reaching process. After conflict elimination, the final group preference can be obtained which will give the ranking of the alternatives. The model can effectively avoid information distortion which is occurred regularly in the linguistic information processing. Finally, an illustrative example is given to illustrate the application of the proposed method and comparative analysis with the existing methods are offered to show the advantages of the proposed method.

Standard partial molar volumes of some aqueous alkanolamines and alkoxyamines at temperatures up to 325 degrees C: functional group additivity in polar organic solutes under hydrothermal conditions.

PubMed

Bulemela, E; Tremaine, Peter R

2008-05-08

Apparent molar volumes of dilute aqueous solutions of monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), N,N-dimethylethanolamine (DMEA), ethylethanolamine (EAE), 2-diethylethanolamine (2-DEEA), and 3-methoxypropylamine (3-MPA) and their salts were measured at temperatures from 150 to 325 degrees C and pressures as high as 15 MPa. The results were corrected for the ionization and used to obtain the standard partial molar volumes, Vo2. A three-parameter equation of state was used to describe the temperature and pressure dependence of the standard partial molar volumes. The fitting parameters were successfully divided into functional group contributions at all temperatures to obtain the standard partial molar volume contributions. Including literature results for alcohols, carboxylic acids, and hydroxycarboxylic acids yielded the standard partial molar volume contributions of the functional groups >CH-, >CH2, -CH3, -OH, -COOH, -O-, -->N, >NH, -NH2, -COO-Na+, -NH3+Cl-, >NH2+Cl-, and -->NH+Cl- over the range (150 degrees C

Development of a recursion RNG-based turbulence model

NASA Technical Reports Server (NTRS)

Zhou, YE; Vahala, George; Thangam, S.

1993-01-01

Reynolds stress closure models based on the recursion renormalization group theory are developed for the prediction of turbulent separated flows. The proposed model uses a finite wavenumber truncation scheme to account for the spectral distribution of energy. In particular, the model incorporates effects of both local and nonlocal interactions. The nonlocal interactions are shown to yield a contribution identical to that from the epsilon-renormalization group (RNG), while the local interactions introduce higher order dispersive effects. A formal analysis of the model is presented and its ability to accurately predict separated flows is analyzed from a combined theoretical and computational stand point. Turbulent flow past a backward facing step is chosen as a test case and the results obtained based on detailed computations demonstrate that the proposed recursion -RNG model with finite cut-off wavenumber can yield very good predictions for the backstep problem.

Evaluation of Offline Models Used to Simulate Components of the Permafrost Carbon Feedback: Experience from the Permafrost Carbon Network Model Integration Group

NASA Astrophysics Data System (ADS)

McGuire, A. D.

2016-12-01

The Model Integration Group of the Permafrost Carbon Network (see http://www.permafrostcarbon.org/) has conducted studies to evaluate the sensitivity of offline terrestrial permafrost and carbon models to both historical and projected climate change. These studies indicate that there is a wide range of (1) initial states permafrost extend and carbon stocks simulated by these models and (2) responses of permafrost extent and carbon stocks to both historical and projected climate change. In this study, we synthesize what has been learned about the variability in initial states among models and the driving factors that contribute to variability in the sensitivity of responses. We conclude the talk with a discussion of efforts needed by (1) the modeling community to standardize structural representation of permafrost and carbon dynamics among models that are used to evaluate the permafrost carbon feedback and (2) the modeling and observational communities to jointly develop data sets and methodologies to more effectively benchmark models.

Unification of gauge, family, and flavor symmetries illustrated in gauged SU(12) models

DOE PAGES

Albright, Carl H.; Feger, Robert P.; Kephart, Thomas W.

2016-04-25

In this study, to explain quark and lepton masses and mixing angles, one has to extend the standard model, and the usual practice is to put the quarks and leptons into irreducible representations of discrete groups. We argue that discrete flavor symmetries (and their concomitant problems) can be avoided if we extend the gauge group. In the framework of SU(12) we give explicit examples of models having varying degrees of predictability obtained by scanning over groups and representations and identifying cases with operators contributing to mass and mixing matrices that need little fine- tuning of prefactors. Fitting with quark andmore » lepton masses run to the GUT scale and known mixing angles allows us to make predictions for the neutrino masses and hierarchy, the octant of the atmospheric mixing angle, leptonic CP violation, Majorana phases, and the effective mass observed in neutrinoless double beta decay.« less

Three-Dimensional Model of Strengths: Examination of Invariance Across Gender, Age, Education Levels, and Marriage Status.

PubMed

Duan, Wenjie; Ho, Samuel Mun Yin

2017-02-01

Strengths are positive qualities that significantly contributed to well-being of individuals and community. Therefore, a reliable and valid measure of strengths for research and practice is needed. The Brief Strengths Scale (BSS) is a newly developed tool for measuring the three-dimensional strengths model (i.e., temperance, intellectual, and interpersonal strength). However, empirical support for the measurement invariance of the BSS has not been obtained. This study examined the three-factor structure of BSS across gender, age, education, and marriage groups in a community sample (n = 375) using multi-group confirmatory factor analysis. After removing one item of each subscale from the original version, the revised model provided a good fit to the data at different subgroups. The revised nine-item BSS indicated that measurement invariance across gender and age groups was achieved. In addition, the measurement was more influenced by social-cultural factors than biological factors.

The measurement of "eating-disorder-thoughts" and "eating-disorder-behaviors": Implications for assessment and detection of eating disorders in epidemiological studies.

PubMed

Miller, Jessie L; Vaillancourt, Tracy; Hanna, Steven E

2009-04-01

To test a theoretically driven second-order factor model of eating disorders, with eating-disordered thoughts and eating-disordered behaviors representing the higher order factors, we conducted a confirmatory factor analysis using a female university student sample (N=1816). The 'Thought' latent construct was comprised of indicators representing fear of fat and dissatisfaction with body shape/weight and the latent construct 'Behavior' was comprised of indicators representing binging, purging and restricting. From the thought and behavior latent factors, composite groups were created by varying the level of thoughts and behaviors (high, moderate, and few/or none). We examined the independent contributions of thoughts and behaviors on a measure of psychopathology (depression). A second-order model of "eating disorder thoughts" and "eating disorder behaviors" was supported by the data, based on model fit, factor loadings, and model parsimony. Mean scores on depression were clinically significant for groups engaged in any level of eating disorder behavior whereas thoughts contributed to risk for depression only at the extreme end. Because of the disproportionate representation of eating disorder thoughts (high) and eating disorder behaviors (low) in non-clinical populations, the measurement and detection of eating disorders may be enhanced by measuring thoughts separate from behaviors.

Neutrophil extracellular traps contribute to the pathogenesis of acid-aspiration-induced ALI/ARDS.

PubMed

Li, Haitao; Zhou, Xiaoting; Tan, Hongyi; Hu, Yongbin; Zhang, Lemeng; Liu, Shuai; Dai, Minhui; Li, Yi; Li, Qian; Mao, Zhi; Pan, Pinhua; Su, Xiaoli; Hu, Chengpin

2018-01-05

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS) is a manifestation of systemic inflammation in the lungs, but the factors that trigger inflammation in ALI/ARDS are unclear. We hypothesized that neutrophil extracellular traps (NETs) contribute to the pathogenesis of acid aspiration-induced ALI/ARDS. Analysis of bronchial aspirates from ARDS patients showed that NETs were significantly correlated with the degree of ARDS (r = -0.5846, p = 0.0359). NETs in bronchoalveolar lavage fluid of acid-aspiration mice were significantly higher (141.6 ± 23.08) at 3 h after injury than those in the sham group (1234 ± 101.9; p = 0.003, n = 5 per group). Exogenous NETs aggravated lung injury, while alvelestat and DNase markedly attenuated the intensity of ARDS. We investigated whether NETs are involved in the severity of gastric aspiration-induced ARDS. Then, a hydrochloric acid aspiration-induced ALI murine model was used to assess whether NETs are pathogenic and whether targeting NETs is protective. Exogenous NETs were administered to mice. Alvelestat can inhibit neutrophil elastase (NE), which serves an important role in NET formation, so we investigated whether alvelestat could protect against ALI in cell and mouse models. NETs may contribute to ALI/ARDS by promoting tissue damage and systemic inflammation. Targeting NETs by alvelestat may be a potential therapeutic strategy.

Learning strategies and general cognitive ability as predictors of gender- specific academic achievement

PubMed Central

Ruffing, Stephanie; Wach, F. -Sophie; Spinath, Frank M.; Brünken, Roland; Karbach, Julia

2015-01-01

Recent research has revealed that learning behavior is associated with academic achievement at the college level, but the impact of specific learning strategies on academic success as well as gender differences therein are still not clear. Therefore, the aim of this study was to investigate gender differences in the incremental contribution of learning strategies over general cognitive ability in the prediction of academic achievement. The relationship between these variables was examined by correlation analyses. A set of t-tests was used to test for gender differences in learning strategies, whereas structural equation modeling as well as multi-group analyses were applied to investigate the incremental contribution of learning strategies for male and female students’ academic performance. The sample consisted of 461 students (mean age = 21.2 years, SD = 3.2). Correlation analyses revealed that general cognitive ability as well as the learning strategies effort, attention, and learning environment were positively correlated with academic achievement. Gender differences were found in the reported application of many learning strategies. Importantly, the prediction of achievement in structural equation modeling revealed that only effort explained incremental variance (10%) over general cognitive ability. Results of multi-group analyses showed no gender differences in this prediction model. This finding provides further knowledge regarding gender differences in learning research and the specific role of learning strategies for academic achievement. The incremental assessment of learning strategy use as well as gender-differences in their predictive value contributes to the understanding and improvement of successful academic development. PMID:26347698

Delineation of areas contributing groundwater to selected receiving surface water bodies for long-term average hydrologic conditions from 1968 to 1983 for Long Island, New York

USGS Publications Warehouse

Misut, Paul E.; Monti,, Jack

2016-10-05

To assist resource managers and planners in developing informed strategies to address nitrogen loading to coastal water bodies of Long Island, New York, the U.S. Geological Survey and the New York State Department of Environmental Conservation initiated a program to delineate a comprehensive dataset of groundwater recharge areas (or areas contributing groundwater), travel times, and outflows to streams and saline embayments on Long Island. A four-layer regional three-dimensional finite-difference groundwater-flow model of hydrologic conditions from 1968 to 1983 was used to provide delineations of 48 groundwater watersheds on Long Island. Sixteen particle starting points were evenly spaced within each of the 4,000- by 4,000-foot model cells that receive water-table recharge and tracked using forward particle-tracking analysis modeling software to outflow zones. For each particle, simulated travel times were grouped by age as follows: less than or equal to 10 years, greater than 10 years and less than or equal to 100 years, greater than 100 years and less than or equal to 1,000 years, and greater than 1,000 years; and simulated ending zones were grouped into 48 receiving water bodies, based on the New York State Department of Environmental Conservation Waterbody Inventory/Priority Waterbodies List. Areal delineation of travel time zones and groundwater contributing areas were generated and a table was prepared presenting the sum of groundwater outflow for each area.

Learning strategies and general cognitive ability as predictors of gender- specific academic achievement.

PubMed

Ruffing, Stephanie; Wach, F-Sophie; Spinath, Frank M; Brünken, Roland; Karbach, Julia

2015-01-01

Recent research has revealed that learning behavior is associated with academic achievement at the college level, but the impact of specific learning strategies on academic success as well as gender differences therein are still not clear. Therefore, the aim of this study was to investigate gender differences in the incremental contribution of learning strategies over general cognitive ability in the prediction of academic achievement. The relationship between these variables was examined by correlation analyses. A set of t-tests was used to test for gender differences in learning strategies, whereas structural equation modeling as well as multi-group analyses were applied to investigate the incremental contribution of learning strategies for male and female students' academic performance. The sample consisted of 461 students (mean age = 21.2 years, SD = 3.2). Correlation analyses revealed that general cognitive ability as well as the learning strategies effort, attention, and learning environment were positively correlated with academic achievement. Gender differences were found in the reported application of many learning strategies. Importantly, the prediction of achievement in structural equation modeling revealed that only effort explained incremental variance (10%) over general cognitive ability. Results of multi-group analyses showed no gender differences in this prediction model. This finding provides further knowledge regarding gender differences in learning research and the specific role of learning strategies for academic achievement. The incremental assessment of learning strategy use as well as gender-differences in their predictive value contributes to the understanding and improvement of successful academic development.

What is Grouping during Binocular Rivalry?

PubMed Central

Stuit, Sjoerd M.; Paffen, Chris L. E.; van der Smagt, Maarten J.; Verstraten, Frans A. J.

2011-01-01

During binocular rivalry, perception alternates between dissimilar images presented dichoptically. Although perception during rivalry is believed to originate from competition at a local level, different rivalry zones are not independent: rival targets that are spaced apart but have similar features tend to be dominant at the same time. We investigated grouping of spatially separated rival targets presented to the same or to different eyes and presented in the same or in different hemifields. We found eye-of-origin to be the strongest cue for grouping during binocular rivalry. Grouping was additionally affected by orientation: identical orientations were grouped longer than dissimilar orientations, even when presented to different eyes. Our results suggest that eye-based and orientation-based grouping is independent and additive in nature. Grouping effects were further modulated by the distribution of the targets across the visual field. That is, grouping within the same hemifield can be stronger or weaker than between hemifields, depending on the eye-of-origin of the grouped targets. We also quantified the contribution of the previous cues to grouping of two images during binocular rivalry. These quantifications can be successfully used to predict the dominance durations of different studies. Incorporating the relative contribution of different cues to grouping, and the dependency on hemifield, into future models of binocular rivalry will prove useful in our understanding of the functional and anatomical basis of the phenomenon of binocular rivalry. PMID:22022312

Repeat exposure to group A streptococcal M protein exacerbates cardiac damage in a rat model of rheumatic heart disease.

PubMed

Gorton, Davina; Sikder, Suchandan; Williams, Natasha L; Chilton, Lisa; Rush, Catherine M; Govan, Brenda L; Cunningham, Madeleine W; Ketheesan, Natkunam

2016-12-01

Rheumatic fever and rheumatic heart disease (RF/RHD) develop following repeated infection with group A streptococci (GAS). We used the Rat Autoimmune Valvulitis (RAV) model of RF/RHD to demonstrate that repetitive booster immunization with GAS-derived recombinant M protein (rM5) resulted in an enhanced anti-cardiac myosin antibody response that may contribute to the breaking of immune tolerance leading to RF/RHD and increased infiltration of heart valves by mononuclear cells. With each boost, more inflammatory cells were observed infiltrating heart tissue which could lead to severe cardiac damage. We also found evidence that both complement and anti-M protein antibodies in serum from rM5-immunized rats have the potential to contribute to inflammation in heart valves by activating cardiac endothelium. More importantly, we have demonstrated by electrocardiography for the first time in the RAV model that elongation of P-R interval follows repetitive boost with rM5. Our observations provide experimental evidence for cardiac alterations following repeated exposure to GAS M protein with immunological and electrophysiological features resembling that seen in humans following recurrent GAS infection.

The Differential Effect of Arm Movements during Gait on the Forward Acceleration of the Centre of Mass in Children with Cerebral Palsy and Typically Developing Children.

PubMed

Meyns, Pieter; Molenaers, Guy; Duysens, Jacques; Jonkers, Ilse

2017-01-01

Background: We aimed to study the contribution of upper limb movements to propulsion during walking in typically developing (TD) children ( n = 5) and children with hemiplegic and diplegic cerebral palsy (CP; n = 5 and n = 4, respectively). Methods: Using integrated three-dimensional motion capture data and a scaled generic musculoskeletal model that included upper limbs, we generated torque driven simulations of gait in OpenSim. Induced acceleration analyses were then used to determine the contributions of the individual actuators located at the relevant degrees of freedoms of the upper and lower limb joints to the forward acceleration of the COM at each time point of the gait simulation. The mean values of the contribution of the actuators of upper limbs, lower limbs, and gravity in different phases of the gait cycle were compared between the three groups. Findings: The results indicated a limited contribution of the upper limb actuators to COM forward acceleration compared to the contribution of lower limbs and gravity, in the three groups. In diplegic CP, the contribution of the upper limbs seemed larger compared to TD during the preswing and swing phases of gait. In hemiplegic CP, the unaffected arm seemed to contribute more to COM deceleration during (pre)swing, while the affected side contributed to COM acceleration. Interpretation: These findings suggest that in the presence of lower limb dysfunction, the contribution of the upper limbs to forward propulsion is altered, although they remain negligible compared to the lower limbs and gravity.

The large soybean (Glycine max) WRKY TF family expanded by segmental duplication events and subsequent divergent selection among subgroups

PubMed Central

2013-01-01

Background WRKY genes encode one of the most abundant groups of transcription factors in higher plants, and its members regulate important biological process such as growth, development, and responses to biotic and abiotic stresses. Although the soybean genome sequence has been published, functional studies on soybean genes still lag behind those of other species. Results We identified a total of 133 WRKY members in the soybean genome. According to structural features of their encoded proteins and to the phylogenetic tree, the soybean WRKY family could be classified into three groups (groups I, II, and III). A majority of WRKY genes (76.7%; 102 of 133) were segmentally duplicated and 13.5% (18 of 133) of the genes were tandemly duplicated. This pattern was not apparent in Arabidopsis or rice. The transcriptome atlas revealed notable differential expression in either transcript abundance or in expression patterns under normal growth conditions, which indicated wide functional divergence in this family. Furthermore, some critical amino acids were detected using DIVERGE v2.0 in specific comparisons, suggesting that these sites have contributed to functional divergence among groups or subgroups. In addition, site model and branch-site model analyses of positive Darwinian selection (PDS) showed that different selection regimes could have affected the evolution of these groups. Sites with high probabilities of having been under PDS were found in groups I, II c, II e, and III. Together, these results contribute to a detailed understanding of the molecular evolution of the WRKY gene family in soybean. Conclusions In this work, all the WRKY genes, which were generated mainly through segmental duplication, were identified in the soybean genome. Moreover, differential expression and functional divergence of the duplicated WRKY genes were two major features of this family throughout their evolutionary history. Positive selection analysis revealed that the different groups have different evolutionary rates. Together, these results contribute to a detailed understanding of the molecular evolution of the WRKY gene family in soybean. PMID:24088323

Aquaporin 1 contributes to chondrocyte apoptosis in a rat model of osteoarthritis.

PubMed

Gao, Hangfei; Gui, Jiancao; Wang, Liming; Xu, Yan; Jiang, Yiqiu; Xiong, Mingyue; Cui, Yongguang

2016-12-01

Aquaporins (AQPs) have been found to be associated with a number of diseases. However, the role of AQP‑1 in the pathogenesis of osteoarthritis remains unclear. We previously found that AQP‑1 expression was upregulated in osteoarthritic cartilage and strongly correlated with caspase‑3 expression and activity. The aim of this study was to further investigate the association of AQP‑1 expression with chondrocyte apoptosis in a rat model of osteoarthritis, using RNA interference to knock down AQP‑1. For this purspose, 72 male Sprague‑Dawley rats were randomly assigned to 3 groups as follows: the control group not treated surgically (n=24), the sham‑operated group (n=24), and the osteoarthritis group (n=24). Osteoarthritis was induced by amputating the anterior cruciate ligament and medial collateral ligament and partially excising the medial meniscus. Chondrocytes from the rats with osteoarthritis were isolated and cultured. shRNAs were used to knock down AQP‑1 expression in the cultured chondrocytes. The expression of AQP‑1 and caspase‑3 was determined by reverse transcription-quantitative polymerase chain reaction. Caspase‑3 activity was measured using a caspase‑3 colorimetric assay. The rats in our model of osteoarthritis exhibited severe cartilage damage. The knockdown of AQP‑1 decreased caspase‑3 expression and activity in the cultured chondrocytes. In addition, the expression of AQP‑1 positively correlated with caspase‑3 expression and activity. Thus, the findings of our study, suggest that AQP‑1 promotes caspase‑3 activation and thereby contributes to chondrocyte apoptosis and to the development of osteoarthritis.

A cost constraint alone has adverse effects on food selection and nutrient density: an analysis of human diets by linear programming.

PubMed

Darmon, Nicole; Ferguson, Elaine L; Briend, André

2002-12-01

Economic constraints may contribute to the unhealthy food choices observed among low socioeconomic groups in industrialized countries. The objective of the present study was to predict the food choices a rational individual would make to reduce his or her food budget, while retaining a diet as close as possible to the average population diet. Isoenergetic diets were modeled by linear programming. To ensure these diets were consistent with habitual food consumption patterns, departure from the average French diet was minimized and constraints that limited portion size and the amount of energy from food groups were introduced into the models. A cost constraint was introduced and progressively strengthened to assess the effect of cost on the selection of foods by the program. Strengthening the cost constraint reduced the proportion of energy contributed by fruits and vegetables, meat and dairy products and increased the proportion from cereals, sweets and added fats, a pattern similar to that observed among low socioeconomic groups. This decreased the nutritional quality of modeled diets, notably the lowest cost linear programming diets had lower vitamin C and beta-carotene densities than the mean French adult diet (i.e., <25% and 10% of the mean density, respectively). These results indicate that a simple cost constraint can decrease the nutrient densities of diets and influence food selection in ways that reproduce the food intake patterns observed among low socioeconomic groups. They suggest that economic measures will be needed to effectively improve the nutritional quality of diets consumed by these populations.

A combined approach for the evaluation of a volatile organic compound emissions inventory.

PubMed

Choi, Yu-Jin; Calabrese, Richard V; Ehrman, Sheryl H; Dickerson, Russell R; Stehr, Jeffrey W

2006-02-01

Emissions inventories significantly affect photochemical air quality model performance and the development of effective control strategies. However, there have been very few studies to evaluate their accuracy. Here, to evaluate a volatile organic compound (VOC) emissions inventory, we implemented a combined approach: comparing the ratios of carbon bond (CB)-IV VOC groups to nitrogen oxides (NOx) or carbon monoxide (CO) using an emission preprocessing model, comparing the ratios of VOC source contributions from a source apportionment technique to NOx or CO, and comparing ratios of CB-IV VOC groups to NOx or CO and the absolute concentrations of CB-IV VOC groups using an air quality model, with the corresponding ratios and concentrations observed at three sites (Maryland, Washington, DC, and New Jersey). The comparisons of the ethene/NOx ratio, the xylene group (XYL)/NOx ratio, and ethene and XYL concentrations between estimates and measurements showed some differences, depending on the comparison approach, at the Maryland and Washington, DC sites. On the other hand, consistent results at the New Jersey site were observed, implying a possible overestimation of vehicle exhaust. However, in the case of the toluene group (TOL), which is emitted mainly from surface coating and printing sources in the solvent utilization category, the ratios of TOL/ NOx or CO, as well as the absolute concentrations revealed an overestimate of these solvent sources by a factor of 1.5 to 3 at all three sites. In addition, the overestimate of these solvent sources agreed with the comparisons of surface coating and printing source contributions relative to NOx from a source apportionment technique to the corresponding value of estimates at the Maryland site. Other studies have also suggested an overestimate of solvent sources, implying a possibility of inaccurate emission factors in estimating VOC emissions from surface coating and printing sources. We tested the impact of these overestimates with a chemical transport model and found little change in ozone but substantial changes in calculated secondary organic aerosol concentrations.

Contribution of hamstring fatigue to quadriceps inhibition following lumbar extension exercise.

PubMed

Hart, Joseph M; Kerrigan, D Casey; Fritz, Julie M; Saliba, Ethan N; Gansneder, Bruce; Ingersoll, Christopher D

2006-01-01

The purpose of this study was to determine the contribution of hamstrings and quadriceps fatigue to quadriceps inhibition following lumbar extension exercise. Regression models were calculated consisting of the outcome variable: quadriceps inhibition and predictor variables: change in EMG median frequency in the quadriceps and hamstrings during lumbar fatiguing exercise. Twenty-five subjects with a history of low back pain were matched by gender, height and mass to 25 healthy controls. Subjects performed two sets of fatiguing isometric lumbar extension exercise until mild (set 1) and moderate (set 2) fatigue of the lumbar paraspinals. Quadriceps and hamstring EMG median frequency were measured while subjects performed fatiguing exercise. A burst of electrical stimuli was superimposed while subjects performed an isometric maximal quadriceps contraction to estimate quadriceps inhibition after each exercise set. Results indicate the change in hamstring median frequency explained variance in quadriceps inhibition following the exercise sets in the history of low back pain group only. Change in quadriceps median frequency explained variance in quadriceps inhibition following the first exercise set in the control group only. In conclusion, persons with a history of low back pain whose quadriceps become inhibited following lumbar paraspinal exercise may be adapting to the fatigue by using their hamstring muscles more than controls. Key PointsA neuromuscular relationship between the lumbar paraspinals and quadriceps while performing lumbar extension exercise may be influenced by hamstring muscle fatigue.QI following lumbar extension exercise in persons with a history of LBP group may involve significant contribution from the hamstring muscle group.More hamstring muscle contribution may be a necessary adaptation in the history of LBP group due to weaker and more fatigable lumbar extensors.

Contribution of Charged Groups to the Enthalpic Stabilization of the Folded States of Globular Proteins

PubMed Central

Dadarlat, Voichita M.; Post, Carol Beth

2016-01-01

In this paper we use the results from all atom MD simulations of proteins and peptides to assess individual contribution of charged atomic groups to the enthalpic stability of the native state of globular proteins and investigate how the distribution of charged atomic groups in terms of solvent accessibility relates to protein enthalpic stability. The contributions of charged groups is calculated using a comparison of nonbonded interaction energy terms from equilibrium simulations of charged amino acid dipeptides in water (the “unfolded state”) and charged amino acids in globular proteins (the “folded state”). Contrary to expectation, the analysis shows that many buried, charged atomic groups contribute favorably to protein enthalpic stability. The strongest enthalpic contributions favoring the folded state come from the carboxylate (COO−) groups of either Glu or Asp. The contributions from Arg guanidinium groups are generally somewhat stabilizing, while NH3+ groups from Lys contribute little toward stabilizing the folded state. The average enthalpic gain due to the transfer of a methyl group in an apolar amino acid from solution to the protein interior is described for comparison. Notably, charged groups that are less exposed to solvent contribute more favorably to protein native-state enthalpic stability than charged groups that are solvent exposed. While solvent reorganization/release has favorable contributions to folding for all charged atomic groups, the variation in folded state stability among proteins comes mainly from the change in the nonbonded interaction energy of charged groups between the unfolded and folded states. A key outcome is that the calculated enthalpic stabilization is found to be inversely proportional to the excess charge density on the surface, in support of an hypothesis proposed previously. PMID:18303881

The Cancer, Educate to Prevent Model-the Potential of School Environment for Primary Prevention of Cancer.

PubMed

Barros, A; Santos, H; Moreira, L; Ribeiro, N; Silva, L; Santos-Silva, F

2016-12-01

Cancer represents one of the main causes of death worldwide; consequently, preventive interventions are of utmost importance in public health education. The leading model of cancer prevention campaigns is based on general and undifferentiated actions mediated by health professionals, focusing on the technical and scientific information but rather ineffective in changing the symbolic, cognitive and practical relationship with the disease. New intervention models are thus required to address cancer literacy, being early interventions targeted to specific groups an elective counterpoint to contribute to positive and durable changes in cancer prevention. Our aim is to evaluate the feasibility and impact of cancer prevention programmes planned as focused interventions in restricted targets and mediated by non-healthcare professionals to increase cancer literacy and promote preventive behaviours. This pilot study evaluates schools' potential as a vehicle for cancer prevention education in a reality shaped by traditional health prevention campaigns. We developed a protocol of systematic surveying in order to review and, in the future, optimize and replicate this ecological model of intervention to other groups and contexts. The implementation of this model has been successful in which concerns to the effectiveness of the training programme for teachers. This led to the development of impactful cancer prevention education projects by trainees targeted to their students, allowing us to argue that it contributes to knowledge and practice in this complex as consensual priority area of intervention.

The Romanian contribution to the COST action TU0801 "Semantic enrichment of 3D city models for sustainable urban development"

NASA Astrophysics Data System (ADS)

Armas, Iuliana; Bostenaru Dan, Maria

2010-05-01

The COST action TU0801 "Semantic enrichment of 3D city models for sustainable urban development" aims at using ontologies to enrich three dimensional models of cities. Such models can be used for various purposes, one of them being disaster management. COST actions are European networks of nationally funded projects, the European Science Foundation funding the networking activities. Romania adhered to the above mentioned COST action in 2009, the nationally funded project being concerned with the use of GIS for the vulnerability to hazards of the city of Bucharest. Among the networking activites Romanian representatives participated in are a training school on 3D GIS for disaster management (with two trainees) and a working group and management committee meeting. It is aimed to further develop the issues of usability and guidance of semantically enriched city models as task from the working group within the Action for the nationally funded project. In this contribution there will be shown how it is aimed to achieve this. One of the issues is on how to extrude GIS to achieve a simple 3D representation for a pilot area in the historic centre of Bucharest. Another one is on how to use this for the study of urbanism aspects, ranging from visual urban composition to the complex 3D aspects in restoration projects, including addition of new floors to buildings.

A multilateral modelling of Youth Soccer Performance Index (YSPI)

NASA Astrophysics Data System (ADS)

Bisyri Husin Musawi Maliki, Ahmad; Razali Abdullah, Mohamad; Juahir, Hafizan; Abdullah, Farhana; Ain Shahirah Abdullah, Nurul; Muazu Musa, Rabiu; Musliha Mat-Rasid, Siti; Adnan, Aleesha; Azura Kosni, Norlaila; Muhamad, Wan Siti Amalina Wan; Afiqah Mohamad Nasir, Nur

2018-04-01

This study aims to identify the most dominant factors that influencing performance of soccer player and to predict group performance for soccer players. A total of 184 of youth soccer players from Malaysia sport school and six soccer academy encompasses as respondence of the study. Exploratory factor analysis (EFA) and Confirmatory factor analysis (CFA) were computed to identify the most dominant factors whereas reducing the initial 26 parameters with recommended >0.5 of factor loading. Meanwhile, prediction of the soccer performance was predicted by regression model. CFA revealed that sit and reach, vertical jump, VO2max, age, weight, height, sitting height, calf circumference (cc), medial upper arm circumference (muac), maturation, bicep, triceps, subscapular, suprailiac, 5M, 10M, and 20M speed were the most dominant factors. Further index analysis forming Youth Soccer Performance Index (YSPI) resulting by categorizing three groups namely, high, moderate, and low. The regression model for this study was significant set as p < 0.001 and R2 is 0.8222 which explained that the model contributed a total of 82% prediction ability to predict the whole set of the variables. The significant parameters in contributing prediction of YSPI are discussed. As a conclusion, the precision of the prediction models by integrating a multilateral factor reflecting for predicting potential soccer player and hopefully can create a competitive soccer games.

Chemical structure-based predictive model for methanogenic anaerobic biodegradation potential.

PubMed

Meylan, William; Boethling, Robert; Aronson, Dallas; Howard, Philip; Tunkel, Jay

2007-09-01

Many screening-level models exist for predicting aerobic biodegradation potential from chemical structure, but anaerobic biodegradation generally has been ignored by modelers. We used a fragment contribution approach to develop a model for predicting biodegradation potential under methanogenic anaerobic conditions. The new model has 37 fragments (substructures) and classifies a substance as either fast or slow, relative to the potential to be biodegraded in the "serum bottle" anaerobic biodegradation screening test (Organization for Economic Cooperation and Development Guideline 311). The model correctly classified 90, 77, and 91% of the chemicals in the training set (n = 169) and two independent validation sets (n = 35 and 23), respectively. Accuracy of predictions of fast and slow degradation was equal for training-set chemicals, but fast-degradation predictions were less accurate than slow-degradation predictions for the validation sets. Analysis of the signs of the fragment coefficients for this and the other (aerobic) Biowin models suggests that in the context of simple group contribution models, the majority of positive and negative structural influences on ultimate degradation are the same for aerobic and methanogenic anaerobic biodegradation.

On an Approach to Testing and Modeling Competence

ERIC Educational Resources Information Center

Shavelson, Richard J.

2013-01-01

E. L. Thorndike contributed significantly to the field of educational and psychological testing as well as more broadly to psychological studies in education. This article follows in his testing legacy. I address the escalating demand, across societal sectors, to measure individual and group competencies. In formulating an approach to measuring…

Voting Power on School Governing Boards: The Countenance of Proportionality.

ERIC Educational Resources Information Center

Kelly, Anthony

2002-01-01

Used the mathematics of cooperative multiperson game theory to analyze the relative strengths of various representative groupings on three models of school governing bodies loosely based on school types in Northern Ireland. Findings contribute to understanding of the distribution of power in committee-like structures. (SLD)

Job Attitudes among Different Occupational Status Groups. An Economic Analysis.

ERIC Educational Resources Information Center

Ronen, Simcha; Sadan, Simcha

1984-01-01

An economic model is applied to employee attitudinal variables to compare the contribution of intrinsic and extrinsic factors to job satisfaction for skilled workers and managers in an electronics manufacturing organization. Intrinsic rewards are found to increase in importance as employment level increases, suggesting different frames of…

When Parents Divorce: Assisting Teens to Adjust through a Group Approach.

ERIC Educational Resources Information Center

Studer, Jeannine R.; Allton, Judith A.

1996-01-01

Addresses factors that contribute to the adjustment difficulties of children and adolescents when their parents divorce. Gender issues, custody, age, parenting style, visitation patterns, socioeconomic considerations, the support system, family size, and the reconstituted family are all discussed. Describes a model for an effective support group…

Making the Monday Connection: Teaching Business Ethics in the Congregation.

ERIC Educational Resources Information Center

Van Buren, Harry J., III

1998-01-01

Discusses three factors that have contributed to the decline of eccelsiastical influences on the ethical decisions of Christians in the workplace. Considers the components of a business-ethics curriculum. Outlines one model for both teaching theological/philosophical bases for moral action and providing support groups for business people…

Agroecology and Health: Lessons from Indigenous Populations.

PubMed

Suárez-Torres, José; Suárez-López, José Ricardo; López-Paredes, Dolores; Morocho, Hilario; Cachiguango-Cachiguango, Luis Enrique; Dellai, William

2017-06-01

The article aims to systematize and disseminate the main contributions of indigenous ancestral wisdom in the agroecological production of food, especially in Latin America. For this purpose, it is necessary to ask whether such knowledge can be accepted by academia research groups and international forums as a valid alternative that could contribute to overcome the world's nutritional problems. Although no new findings are being made, the validity of ancestral knowledge and agroecology is recognized by scientific research, and by international forums organized by agencies of the United Nations. These recommend that governments should implement them in their policies of development, and in the allocation of funds to support these initiatives. Agroecology and ancestral knowledge are being adopted by a growing number of organizations, indigenous peoples and social groups in various parts of the world, as development alternatives that respond to local needs and worldviews. Its productive potential is progressively being recognized at an international level as a model that contributes to improve the condition of people regarding nutritional food.

Fuzzy cognitive mapping in support of integrated ecosystem assessments: Developing a shared conceptual model among stakeholders.

PubMed

Vasslides, James M; Jensen, Olaf P

2016-01-15

Ecosystem-based approaches, including integrated ecosystem assessments, are a popular methodology being used to holistically address management issues in social-ecological systems worldwide. In this study we utilized fuzzy logic cognitive mapping to develop conceptual models of a complex estuarine system among four stakeholder groups. The average number of categories in an individual map was not significantly different among groups, and there were no significant differences between the groups in the average complexity or density indices of the individual maps. When ordered by their complexity scores, eight categories contributed to the top four rankings of the stakeholder groups, with six of the categories shared by at least half of the groups. While non-metric multidimensional scaling (nMDS) analysis displayed a high degree of overlap between the individual models across groups, there was also diversity within each stakeholder group. These findings suggest that while all of the stakeholders interviewed perceive the subject ecosystem as a complex series of social and ecological interconnections, there are a core set of components that are present in most of the groups' models that are crucial in managing the system towards some desired outcome. However, the variability in the connections between these core components and the rest of the categories influences the exact nature of these outcomes. Understanding the reasons behind these differences will be critical to developing a shared conceptual model that will be acceptable to all stakeholder groups and can serve as the basis for an integrated ecosystem assessment. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evaluating the risk of decompression sickness for a yo-yo dive using a rat model.

PubMed

Ofir, Dror; Yanir, Yoav; Abramovich, Amir; Bar, Ronen; Arieli, Yehuda

2016-01-01

The frequent ascents made during yo-yo diving may contribute to gas bubble clearance but paradoxically may also increase the risk of central nervous system decompression illness (DCI). We evaluated the risk of DCI due to yo-yo dives with very short surface intervals, using a controlled animal model. Dives were conducted on air to a depth of 90 meters (10 atmospheres absolute) for 32 minutes of bottom time, at a descent/ascent rate of 10 meters/ minute. Sprague-Dawley rats weighing ~ 300 grams were divided randomly into three groups. Group A performed a square dive protocol without any surface intervals, Group B conducted a protocol that included two surface intervals during the dive, and Group C performed a protocol with three surface intervals. Ascent/descent rate for surface intervals, each lasting one minute, was also 10 meters/minute. Manifestations of DCI were observed in 13 of 16 animals in Group A (81.3%), six of 12 in Group B (58.3%), and two of 12 in Group C (16.7%). Mortality rates were similar in all groups. Surface intervals during dives breathing air significantly reduced DCI risk in the rat. Further studies are required using a larger animal model to reinforce the results of the present investigation.

Numerical renormalization group method for entanglement negativity at finite temperature

NASA Astrophysics Data System (ADS)

Shim, Jeongmin; Sim, H.-S.; Lee, Seung-Sup B.

2018-04-01

We develop a numerical method to compute the negativity, an entanglement measure for mixed states, between the impurity and the bath in quantum impurity systems at finite temperature. We construct a thermal density matrix by using the numerical renormalization group (NRG), and evaluate the negativity by implementing the NRG approximation that reduces computational cost exponentially. We apply the method to the single-impurity Kondo model and the single-impurity Anderson model. In the Kondo model, the negativity exhibits a power-law scaling at temperature much lower than the Kondo temperature and a sudden death at high temperature. In the Anderson model, the charge fluctuation of the impurity contributes to the negativity even at zero temperature when the on-site Coulomb repulsion of the impurity is finite, while at low temperature the negativity between the impurity spin and the bath exhibits the same power-law scaling behavior as in the Kondo model.

The social accident: a theoretical model and a research agenda for studying the influence of social and cultural characteristics on motor vehicle accidents.

PubMed

Factor, Roni; Mahalel, David; Yair, Gad

2007-09-01

The paper develops a sociological model to explain collisions between two drivers or more. The "Social Accident" model presented here integrates empirical findings from prior studies and extant sociological theories. Sociological theory posits that social groups have unique cultural characteristics, which include a distinctive world view and ways of operating that influence its members. These cultural characteristics may cause drivers in different groups to interpret a given situation differently; therefore, they will make conflicting decisions that may possibly lead to road accidents. The proposed model may contribute to an understanding of the social mechanism related to interactions and communication among drivers by presenting new directions for understanding accidents and collisions. The paper concludes with suggestions for future research that will employ the model to assess its predictive and practical utility.

Repeatedly measured material and behavioral factors changed the explanation of socioeconomic inequalities in all-cause mortality.

PubMed

Oude Groeniger, Joost; Kamphuis, Carlijn B; Mackenbach, Johan P; van Lenthe, Frank J

2017-11-01

We examined whether using repeatedly measured material and behavioral factors contributed differently to socioeconomic inequalities in all-cause mortality compared to one baseline measurement. Data from the Dutch prospective GLOBE cohort were linked to mortality register data (1991-2013; N = 4,851). Socioeconomic position was measured at baseline by educational level and occupation. Material factors (financial difficulties, housing tenure, health insurance) and behavioral factors (smoking, leisure time physical activity, sports participation, and body mass index) were self-reported in 1991, 1997, and 2004. Cox proportional hazards regression and bootstrap methods were used to examine the contribution of baseline-only and time-varying risk factors to socioeconomic inequalities in mortality. Men and women in the lowest educational and occupational groups were at an increased risk of dying compared to the highest groups. The contribution of material factors to socioeconomic inequalities in mortality was smaller when multiple instead of baseline-only measurements were used (25%-65% vs. 49%-93%). The contribution of behavioral factors was larger when multiple measurements were used (39%-51% vs. 19%-40%). Inclusion of time-dependent risk factors contributes to understanding socioeconomic inequalities in mortality, but careful examination of the underlying mechanisms and suitability of the model is required. Copyright © 2017 Elsevier Inc. All rights reserved.

Influence of Bone and Muscle Injuries on the Osteogenic Potential of Muscle Progenitors: Contribution of Tissue Environment to Heterotopic Ossification

PubMed Central

Molligan, Jeremy; Mitchell, Reed; Schon, Lew; Achilefu, Samuel; Zahoor, Talal; Cho, Young; Loube, Jeffery

2016-01-01

By using surgical mouse models, this study investigated how the tissue environment influences the osteogenic potential of muscle progenitors (m-progenitors) and potentially contributes to heterotopic ossification (HO). Injury was induced by clamping the gluteus maximus and medius (group M) or osteotomy of greater trochanter (group O) on the right hip, as well as combined muscle injury and osteotomy of greater trochanter (group M+O). The gluteus maximus and medius of the operated hips were harvested at days 1, 3, 5, and 10 for isolation of m-progenitors. The cells were cultured in an osteogenic medium for 3 weeks, and osteogenesis was evaluated by matrix mineralization and the expression of osteogenesis-related genes. The expression of type I collagen, RUNX2 (runt-related transcription factor 2), and osteocalcin by the m-progenitors of group M+O was significantly increased, compared with groups M and O. Osteogenic m-progenitors in group O increased the expression of bone morphogenetic protein 2 and also bone morphogenetic protein antagonist differential screening-selected gene aberrative in neuroblastoma. On histology, there was calcium deposition mostly in the muscles of group M+O harvested at day 10. CD56, representing myogenic progenitors, was highly expressed in the m-progenitors isolated from group M (day 10), but m-progenitors of group M+O (day 10) exhibited the highest expression of platelet-derived growth factor receptor α (PDGFR-α), a marker of muscle-derived mesenchymal stem cells (M-MSCs). The expressions of PDGFR-α and RUNX2 were colocalized in osteogenic m-progenitors. The data indicate that the tissue environment simulated in the M+O model is a favorable condition for HO formation. Most likely, M-MSCs, rather than myogenic progenitors, in the m-progenitors participate in HO formation. Significance The prevalence of traumatic heterotopic ossification (HO) is high in war injury. The pathogenesis of HO is still unknown. This study clarified the contribution of a tissue environment created by bone or muscle injury to the formation of HO. The study also found that muscle-derived mesenchymal stem cells, but not myogenic progenitors, are involved in the formation of HO. The findings of this study could be used to strategize the prevention and treatment of HO. PMID:27112178

Influence of Bone and Muscle Injuries on the Osteogenic Potential of Muscle Progenitors: Contribution of Tissue Environment to Heterotopic Ossification.

PubMed

Molligan, Jeremy; Mitchell, Reed; Schon, Lew; Achilefu, Samuel; Zahoor, Talal; Cho, Young; Loube, Jeffery; Zhang, Zijun

2016-06-01

: By using surgical mouse models, this study investigated how the tissue environment influences the osteogenic potential of muscle progenitors (m-progenitors) and potentially contributes to heterotopic ossification (HO). Injury was induced by clamping the gluteus maximus and medius (group M) or osteotomy of greater trochanter (group O) on the right hip, as well as combined muscle injury and osteotomy of greater trochanter (group M+O). The gluteus maximus and medius of the operated hips were harvested at days 1, 3, 5, and 10 for isolation of m-progenitors. The cells were cultured in an osteogenic medium for 3 weeks, and osteogenesis was evaluated by matrix mineralization and the expression of osteogenesis-related genes. The expression of type I collagen, RUNX2 (runt-related transcription factor 2), and osteocalcin by the m-progenitors of group M+O was significantly increased, compared with groups M and O. Osteogenic m-progenitors in group O increased the expression of bone morphogenetic protein 2 and also bone morphogenetic protein antagonist differential screening-selected gene aberrative in neuroblastoma. On histology, there was calcium deposition mostly in the muscles of group M+O harvested at day 10. CD56, representing myogenic progenitors, was highly expressed in the m-progenitors isolated from group M (day 10), but m-progenitors of group M+O (day 10) exhibited the highest expression of platelet-derived growth factor receptor α (PDGFR-α), a marker of muscle-derived mesenchymal stem cells (M-MSCs). The expressions of PDGFR-α and RUNX2 were colocalized in osteogenic m-progenitors. The data indicate that the tissue environment simulated in the M+O model is a favorable condition for HO formation. Most likely, M-MSCs, rather than myogenic progenitors, in the m-progenitors participate in HO formation. The prevalence of traumatic heterotopic ossification (HO) is high in war injury. The pathogenesis of HO is still unknown. This study clarified the contribution of a tissue environment created by bone or muscle injury to the formation of HO. The study also found that muscle-derived mesenchymal stem cells, but not myogenic progenitors, are involved in the formation of HO. The findings of this study could be used to strategize the prevention and treatment of HO. ©AlphaMed Press.

Advances in segmentation modeling for health communication and social marketing campaigns.

PubMed

Albrecht, T L; Bryant, C

1996-01-01

Large-scale communication campaigns for health promotion and disease prevention involve analysis of audience demographic and psychographic factors for effective message targeting. A variety of segmentation modeling techniques, including tree-based methods such as Chi-squared Automatic Interaction Detection and logistic regression, are used to identify meaningful target groups within a large sample or population (N = 750-1,000+). Such groups are based on statistically significant combinations of factors (e.g., gender, marital status, and personality predispositions). The identification of groups or clusters facilitates message design in order to address the particular needs, attention patterns, and concerns of audience members within each group. We review current segmentation techniques, their contributions to conceptual development, and cost-effective decision making. Examples from a major study in which these strategies were used are provided from the Texas Women, Infants and Children Program's Comprehensive Social Marketing Program.

Psychology in patient-centered medical homes: Reducing health disparities and promoting health equity.

PubMed

Farber, Eugene W; Ali, Mana K; Van Sickle, Kristi S; Kaslow, Nadine J

2017-01-01

With persisting health disparities contributing to a disproportionate impact on the health and well-being of socially disenfranchised and medically underserved populations, the emerging patient-centered medical home (PCMH) model offers promise in bridging the health disparities divide. Because behavioral health care is an important component of the PCMH, psychologists have significant opportunity to contribute to the development and implementation of PCMH services in settings that primarily serve medically underserved communities. In this article, after briefly defining the PCMH model and its role in clinical settings for medically underserved populations for whom health disparities are present, roles of psychologists as interprofessional collaborators on PCMH medical care teams are explored. Next, the constellation of competencies that position psychologists as behavioral health specialists to contribute to PCMH care teams for medically underserved groups are characterized. The article concludes with reflections on the prospects for psychologists to make tangible contributions as health care team members toward reducing health disparities and promoting health equity in patients served in the PCMH. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Temperature-Dependent Estimation of Gibbs Energies Using an Updated Group-Contribution Method.

PubMed

Du, Bin; Zhang, Zhen; Grubner, Sharon; Yurkovich, James T; Palsson, Bernhard O; Zielinski, Daniel C

2018-06-05

Reaction-equilibrium constants determine the metabolite concentrations necessary to drive flux through metabolic pathways. Group-contribution methods offer a way to estimate reaction-equilibrium constants at wide coverage across the metabolic network. Here, we present an updated group-contribution method with 1) additional curated thermodynamic data used in fitting and 2) capabilities to calculate equilibrium constants as a function of temperature. We first collected and curated aqueous thermodynamic data, including reaction-equilibrium constants, enthalpies of reaction, Gibbs free energies of formation, enthalpies of formation, entropy changes of formation of compounds, and proton- and metal-ion-binding constants. Next, we formulated the calculation of equilibrium constants as a function of temperature and calculated the standard entropy change of formation (Δ f S ∘ ) using a model based on molecular properties. The median absolute error in estimating Δ f S ∘ was 0.013 kJ/K/mol. We also estimated magnesium binding constants for 618 compounds using a linear regression model validated against measured data. We demonstrate the improved performance of the current method (8.17 kJ/mol in median absolute residual) over the current state-of-the-art method (11.47 kJ/mol) in estimating the 185 new reactions added in this work. The efforts here fill in gaps for thermodynamic calculations under various conditions, specifically different temperatures and metal-ion concentrations. These, to our knowledge, new capabilities empower the study of thermodynamic driving forces underlying the metabolic function of organisms living under diverse conditions. Copyright © 2018 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Discriminant analysis of cardiovascular and respiratory variables for classification of road cyclists by specialty.

PubMed

Nikolić, Biljana; Martinović, Jelena; Matić, Milan; Stefanović, Đorđe

2018-05-29

Different variables determine the performance of cyclists, which brings up the question how these parameters may help in their classification by specialty. The aim of the study was to determine differences in cardiorespiratory parameters of male cyclists according to their specialty, flat rider (N=21), hill rider (N=35) and sprinter (N=20) and obtain the multivariate model for further cyclists classification by specialties, based on selected variables. Seventeen variables were measured at submaximal and maximum load on the cycle ergometer Cosmed E 400HK (Cosmed, Rome, Italy) (initial 100W with 25W increase, 90-100 rpm). Multivariate discriminant analysis was used to determine which variables group cyclists within their specialty, and to predict which variables can direct cyclists to a particular specialty. Among nine variables that statistically contribute to the discriminant power of the model, achieved power on the anaerobic threshold and the produced CO2 had the biggest impact. The obtained discriminatory model correctly classified 91.43% of flat riders, 85.71% of hill riders, while sprinters were classified completely correct (100%), i.e. 92.10% of examinees were correctly classified, which point out the strength of the discriminatory model. Respiratory indicators mostly contribute to the discriminant power of the model, which may significantly contribute to training practice and laboratory tests in future.

Influence of muscle groups' activation on proximal femoral growth tendency.

PubMed

Yadav, Priti; Shefelbine, Sandra J; Pontén, Eva; Gutierrez-Farewik, Elena M

2017-12-01

Muscle and joint contact force influence stresses at the proximal growth plate of the femur and thus bone growth, affecting the neck shaft angle (NSA) and femoral anteversion (FA). This study aims to illustrate how different muscle groups' activation during gait affects NSA and FA development in able-bodied children. Subject-specific femur models were developed for three able-bodied children (ages 6, 7, and 11 years) using magnetic resonance images. Contributions of different muscle groups-hip flexors, hip extensors, hip adductors, hip abductors, and knee extensors-to overall hip contact force were computed. Specific growth rate for the growth plate was computed, and the growth was simulated in the principal stress direction at each element in the growth front. The predicted growth indicated decreased NSA and FA (of about [Formula: see text] over a four-month period) for able-bodied children. Hip abductors contributed the most, and hip adductors, the least, to growth rate. All muscles groups contributed to a decrease in predicted NSA ([Formula: see text]0.01[Formula: see text]-0.04[Formula: see text] and FA ([Formula: see text]0.004[Formula: see text]-[Formula: see text]), except hip extensors and hip adductors, which showed a tendency to increase the FA ([Formula: see text]0.004[Formula: see text]-[Formula: see text]). Understanding influences of different muscle groups on long bone growth tendency can help in treatment planning for growing children with affected gait.

Do Intermediate Radiation Doses Contribute to Late Rectal Toxicity? An Analysis of Data From Radiation Therapy Oncology Group Protocol 94-06

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

Tucker, Susan L., E-mail: sltucker@mdanderson.org; Dong, Lei; Michalski, Jeff M.

2012-10-01

Purpose: To investigate whether the volumes of rectum exposed to intermediate doses, from 30 to 50 Gy, contribute to the risk of Grade {>=}2 late rectal toxicity among patients with prostate cancer receiving radiotherapy. Methods and Materials: Data from 1009 patients treated on Radiation Therapy Oncology Group protocol 94-06 were analyzed using three approaches. First, the contribution of intermediate doses to a previously published fit of the Lyman-Kutcher-Burman (LKB) normal tissue complication probability (NTCP) model was determined. Next, the extent to which intermediate doses provide additional risk information, after taking the LKB model into account, was investigated. Third, the proportionmore » of rectum receiving doses higher than a threshold, VDose, was computed for doses ranging from 5 to 85 Gy, and a multivariate Cox proportional hazards model was used to determine which of these parameters were significantly associated with time to Grade {>=}2 late rectal toxicity. Results: Doses <60 Gy had no detectable impact on the fit of the LKB model, as expected on the basis of the small estimate of the volume parameter (n = 0.077). Furthermore, there was no detectable difference in late rectal toxicity among cohorts with similar risk estimates from the LKB model but with different volumes of rectum exposed to intermediate doses. The multivariate Cox proportional hazards model selected V75 as the only value of VDose significantly associated with late rectal toxicity. Conclusions: There is no evidence from these data that intermediate doses influence the risk of Grade {>=}2 late rectal toxicity. Instead, the critical doses for this endpoint seem to be {>=}75 Gy. It is hypothesized that cases of Grade {>=}2 late rectal toxicity occurring among patients with V75 less than approximately 12% may be due to a 'background' level of risk, likely due mainly to biological factors.« less

Group contribution methodology based on the statistical associating fluid theory for heteronuclear molecules formed from Mie segments.

PubMed

Papaioannou, Vasileios; Lafitte, Thomas; Avendaño, Carlos; Adjiman, Claire S; Jackson, George; Müller, Erich A; Galindo, Amparo

2014-02-07

A generalization of the recent version of the statistical associating fluid theory for variable range Mie potentials [Lafitte et al., J. Chem. Phys. 139, 154504 (2013)] is formulated within the framework of a group contribution approach (SAFT-γ Mie). Molecules are represented as comprising distinct functional (chemical) groups based on a fused heteronuclear molecular model, where the interactions between segments are described with the Mie (generalized Lennard-Jonesium) potential of variable attractive and repulsive range. A key feature of the new theory is the accurate description of the monomeric group-group interactions by application of a high-temperature perturbation expansion up to third order. The capabilities of the SAFT-γ Mie approach are exemplified by studying the thermodynamic properties of two chemical families, the n-alkanes and the n-alkyl esters, by developing parameters for the methyl, methylene, and carboxylate functional groups (CH3, CH2, and COO). The approach is shown to describe accurately the fluid-phase behavior of the compounds considered with absolute average deviations of 1.20% and 0.42% for the vapor pressure and saturated liquid density, respectively, which represents a clear improvement over other existing SAFT-based group contribution approaches. The use of Mie potentials to describe the group-group interaction is shown to allow accurate simultaneous descriptions of the fluid-phase behavior and second-order thermodynamic derivative properties of the pure fluids based on a single set of group parameters. Furthermore, the application of the perturbation expansion to third order for the description of the reference monomeric fluid improves the predictions of the theory for the fluid-phase behavior of pure components in the near-critical region. The predictive capabilities of the approach stem from its formulation within a group-contribution formalism: predictions of the fluid-phase behavior and thermodynamic derivative properties of compounds not included in the development of group parameters are demonstrated. The performance of the theory is also critically assessed with predictions of the fluid-phase behavior (vapor-liquid and liquid-liquid equilibria) and excess thermodynamic properties of a variety of binary mixtures, including polymer solutions, where very good agreement with the experimental data is seen, without the need for adjustable mixture parameters.

Lin Receives 2010 Natural Hazards Focus Group Award for Graduate Research

NASA Astrophysics Data System (ADS)

2010-11-01

Ning Lin has been awarded the Natural Hazards Focus Group Award for Graduate Research, given annually to a recent Ph.D. recipient for outstanding contributions to natural hazards research. Lin's thesis is entitled “Multi-hazard risk analysis related to hurricanes.” She is scheduled to present an invited talk in the Extreme Natural Events: Modeling, Prediction, and Mitigation session (NH20) during the 2010 AGU Fall Meeting, held 13-17 December in San Francisco, Calif. Lin will be formally presented with the award at the Natural Hazards focus group reception on 14 December 2010.

Identification of character-impact odorants in a cola-flavored carbonated beverage by quantitative analysis and omission studies of aroma reconstitution models.

PubMed

Lorjaroenphon, Yaowapa; Cadwallader, Keith R

2015-01-28

Thirty aroma-active components of a cola-flavored carbonated beverage were quantitated by stable isotope dilution assays, and their odor activity values (OAVs) were calculated. The OAV results revealed that 1,8-cineole, (R)-(-)-linalool, and octanal made the greatest contribution to the overall aroma of the cola. A cola aroma reconstitution model was constructed by adding 20 high-purity standards to an aqueous sucrose-phosphoric acid solution. The results of headspace solid-phase microextraction and sensory analyses were used to adjust the model to better match authentic cola. The rebalanced model was used as a complete model for the omission study. Sensory results indicated that omission of a group consisting of methyleugenol, (E)-cinnamaldehyde, eugenol, and (Z)- and (E)-isoeugenols differed from the complete model, while omission of the individual components of this group did not differ from the complete model. These results indicate that a balance of numerous odorants is responsible for the characteristic aroma of cola-flavored carbonated beverages.

Randomization Does Not Help Much, Comparability Does

PubMed Central

Saint-Mont, Uwe

2015-01-01

According to R.A. Fisher, randomization “relieves the experimenter from the anxiety of considering innumerable causes by which the data may be disturbed.” Since, in particular, it is said to control for known and unknown nuisance factors that may considerably challenge the validity of a result, it has become very popular. This contribution challenges the received view. First, looking for quantitative support, we study a number of straightforward, mathematically simple models. They all demonstrate that the optimism surrounding randomization is questionable: In small to medium-sized samples, random allocation of units to treatments typically yields a considerable imbalance between the groups, i.e., confounding due to randomization is the rule rather than the exception. In the second part of this contribution, the reasoning is extended to a number of traditional arguments in favour of randomization. This discussion is rather non-technical, and sometimes touches on the rather fundamental Frequentist/Bayesian debate. However, the result of this analysis turns out to be quite similar: While the contribution of randomization remains doubtful, comparability contributes much to a compelling conclusion. Summing up, classical experimentation based on sound background theory and the systematic construction of exchangeable groups seems to be advisable. PMID:26193621

Contribution of Food Groups to Energy and Nutrient Intakes in Five Developed Countries.

PubMed

Auestad, Nancy; Hurley, Judith S; Fulgoni, Victor L; Schweitzer, Cindy M

2015-06-08

Economic growth in developing countries and globalization of the food sector is leading to increasingly similar food consumption patterns worldwide. The aim of this study was to describe similarities and differences in the contributions of main food groups to energy and nutrient intakes in five developed countries across three continents. We obtained summary reports of national food consumption survey data from Australia, France, Denmark, the Netherlands, and the United States. Survey years spanned 2003-2012; sample size ranged from 1444 to 17,386. To mitigate heterogeneity of food groups across countries, we recategorized each survey's reported food groups and subgroups into eight main food groups and, for three countries, a ninth "mixed dishes" group. We determined the percent contribution of each food group to mean daily intakes of energy, saturated fat, sodium, fiber, and ten vitamins and minerals that are commonly under-consumed. Differences in findings from surveys utilizing a foods-as-consumed versus a disaggregated or ingredients approach to food group composition and contributions from the milk and milk products group, a source of several under-consumed nutrients, were explored. Patterns of food group contributions to energy and nutrient intakes were generally similar across countries. Some differences were attributable to the analytical approach used by the surveys. For the meat/protein, milk and milk products, vegetables, and fruit groups, percent contributions to key nutrient intakes exceeded percent contributions to energy intake. The mixed dishes group provided 10%-20% of total daily energy and a similar 10%-25% of the daily intake of several nutrients. This descriptive study contributes to an understanding of food group consumption patterns in developed countries.

Contribution of Food Groups to Energy and Nutrient Intakes in Five Developed Countries

PubMed Central

Auestad, Nancy; Hurley, Judith S.; Fulgoni, Victor L.; Schweitzer, Cindy M.

2015-01-01

Economic growth in developing countries and globalization of the food sector is leading to increasingly similar food consumption patterns worldwide. The aim of this study was to describe similarities and differences in the contributions of main food groups to energy and nutrient intakes in five developed countries across three continents. We obtained summary reports of national food consumption survey data from Australia, France, Denmark, the Netherlands, and the United States. Survey years spanned 2003–2012; sample size ranged from 1444 to 17,386. To mitigate heterogeneity of food groups across countries, we recategorized each survey’s reported food groups and subgroups into eight main food groups and, for three countries, a ninth “mixed dishes” group. We determined the percent contribution of each food group to mean daily intakes of energy, saturated fat, sodium, fiber, and ten vitamins and minerals that are commonly under-consumed. Differences in findings from surveys utilizing a foods-as-consumed versus a disaggregated or ingredients approach to food group composition and contributions from the milk and milk products group, a source of several under-consumed nutrients, were explored. Patterns of food group contributions to energy and nutrient intakes were generally similar across countries. Some differences were attributable to the analytical approach used by the surveys. For the meat/protein, milk and milk products, vegetables, and fruit groups, percent contributions to key nutrient intakes exceeded percent contributions to energy intake. The mixed dishes group provided 10%–20% of total daily energy and a similar 10%–25% of the daily intake of several nutrients. This descriptive study contributes to an understanding of food group consumption patterns in developed countries. PMID:26061017

Empirical support for global integrated assessment modeling: Productivity trends and technological change in developing countries' agriculture and electric power sectors

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

Sathaye, Jayant A.

2000-04-01

Integrated assessment (IA) modeling of climate policy is increasingly global in nature, with models incorporating regional disaggregation. The existing empirical basis for IA modeling, however, largely arises from research on industrialized economies. Given the growing importance of developing countries in determining long-term global energy and carbon emissions trends, filling this gap with improved statistical information on developing countries' energy and carbon-emissions characteristics is an important priority for enhancing IA modeling. Earlier research at LBNL on this topic has focused on assembling and analyzing statistical data on productivity trends and technological change in the energy-intensive manufacturing sectors of five developing countries,more » India, Brazil, Mexico, Indonesia, and South Korea. The proposed work will extend this analysis to the agriculture and electric power sectors in India, South Korea, and two other developing countries. They will also examine the impact of alternative model specifications on estimates of productivity growth and technological change for each of the three sectors, and estimate the contribution of various capital inputs--imported vs. indigenous, rigid vs. malleable-- in contributing to productivity growth and technological change. The project has already produced a data resource on the manufacturing sector which is being shared with IA modelers. This will be extended to the agriculture and electric power sectors, which would also be made accessible to IA modeling groups seeking to enhance the empirical descriptions of developing country characteristics. The project will entail basic statistical and econometric analysis of productivity and energy trends in these developing country sectors, with parameter estimates also made available to modeling groups. The parameter estimates will be developed using alternative model specifications that could be directly utilized by the existing IAMs for the manufacturing, agriculture, and electric power sectors.« less

Risk factors associated with open gingival embrasures after orthodontic treatment.

PubMed

An, Sang Su; Choi, Yoon Jeong; Kim, Ji Young; Chung, Chooryung J; Kim, Kyung-Ho

2018-05-01

To investigate the incidence of and contributing factors to open gingival embrasures between the central incisors after orthodontic treatment. One hundred posttreatment patients (29 men and 71 women; mean age, 24.7 years) were divided retrospectively into occurrence and nonoccurrence groups based on intraoral photographs. Based on the severity, the occurrence group was further divided into mild, moderate, and severe groups. Parameters from periapical radiographs, superimposed lateral cephalograms, and study models were compared between the occurrence and the nonoccurrence groups by using independent t-tests and were also analyzed on the basis of severity via analysis of variance. Logistic regression analysis was performed to identify the contributing factors to open gingival embrasures. The incidence of open gingival embrasures between the central incisors was 22% and 36% in the maxilla and the mandible, respectively. Lingual movement of the incisors, distance from the contact point to the alveolar crest after treatment, antero-posterior overlap of the two central incisors before treatment in the maxilla, and distance from the contact point to the alveolar crest after treatment in the mandible were significantly associated with the occurrence of open gingival embrasures ( P < .05). In the mandible, the amount of intrusion was significantly related to severity ( P < .05). The incidence of open gingival embrasures following orthodontic tooth movement is high. Therefore, attention should be paid to the contributing factors to prevent or reduce the occurrence of open gingival embrasures.

Multiscale Computational Modeling of the Nanostructure of Solid Dispersions of Hydroxypropyl Methylcellulose Acetate Succinate (HPMCAS) and Phenytoin.

PubMed

Huang, Wenjun; Mandal, Taraknath; Larson, Ronald G

2017-10-02

We recently developed coarse-grained (CG) force fields for hydroxypropyl methylcellulose acetate succinate (HPMCAS) polymers and the model drug molecule phenytoin, and a continuum transport model to study the polymer-drug nanostructures presented during a dissolution test after solvation of solid dispersion particles. We model the polymer-drug interactions that contribute to suppression of drug aggregation, release, and crystal growth during the dissolution process, and we take these as indicators of polymer effectiveness. We find that the size and the intermolecular interaction strength of the functional group and the drug loading concentration are the major factors that impact the effectiveness of the polymeric excipient. The hydroxypropyl acetyl group is the most effective functional group, followed by the acetyl group, while the deprotonated succinyl group is the least effective functional group, except that the deprotonated succinyl group at the 6-position is very effective in slowing down the phenytoin crystal growth. Our simulation results thus suggest HPMCAS with higher acetyl and lower succinyl content is more effective in promoting phenytoin solubility in dissolution media, and polymers become less effective when drug loading becomes high (i.e., 50% of the mass of the polymer/drug solid dispersion), agreeing with previous experimental studies. In addition, our transport model indicates that the drug release time from a solid dispersion particle of 2 μm diameter is less than 10 min, correlating well with the experimental time scale for a typical dissolution profile to reach maximum peak concentration. Our modeling effort, therefore, provides new avenues to understand the dissolution behavior of complex HPMCAS-phenytoin solid dispersions and offers a new design tool to optimize the formulation. Moreover, the systematic and robust approach used in our computational models can be extended to other polymeric excipients and drug candidates.

Family and peer influences on adjustment among Chinese, Filipino, and White youth.

PubMed

Willgerodt, Mayumi Anne

2008-01-01

Little is known about the influence of parent-adolescent relationships and peer behavior on emotional distress and risky behaviors among Asian American adolescents; in particular, cross-cultural and longitudinal examinations are missing from the extant research. To test and compare a theoretical model examining the influence of family and peer factors on adolescent distress and risky behavior over time, using a nationally representative sample of Chinese, Filipino, and White adolescents. Data were utilized from Waves I (1994) and II (1995) of the National Longitudinal Study on Adolescent Health; the sample is composed of 194 Chinese, 345 Filipino, and 395 White adolescents and weighted to correct for design effects, yielding a nationally representative sample. Structural equation modeling was used to test the theoretical model for each ethnic group separately followed by multiple-group analyses. The measurement model was examined for each ethnic group, using both unweighted and weighted samples, and was deemed equivalent across groups. Tests of the theoretical model by ethnicity revealed that for each group, family bonds have significant negative effects on emotional distress and risky behaviors. For Filipino and White youth, peer risky behaviors influenced risky behaviors. Multiple-group analyses of the theoretical model indicated that the three ethnic groups did not differ significantly from one another. Findings suggest that family bonds and peer behavior exert significant influences on psychological and behavioral outcomes in Asian American youth and that these influences appear to be similar with White adolescents. Future research should be directed toward incorporating variables known to contribute to the impact of distress and risky behaviors in model testing and validating findings from this study.

Development of injury in a rat model of chronic renal allograft rejection: effect of dietary protein restriction.

PubMed

Bombas, A; Stein-Oakley, A N; Baxter, K; Thomson, N M; Jablonski, P

1999-01-01

Non-allogeneic factors such as increased nephron "workload" may contribute to chronic renal allograft rejection. Reducing dietary protein from 20% to 8% was tested in a model of chronic rejection: Dark Agouti kidney to Albino Surgery recipient, "tolerised" by previous donor blood transfusions. Survival, weight gain, serum creatinine concentration and creatinine clearance were similar for both groups at all times. Urinary protein was significantly (P < 0.05) lower in the low-protein (LP) group 1 month after transplantation. After 3 and 6 months, both groups demonstrated mild chronic rejection. After 6 months, tubular atrophy was significantly (P < 0.05) less in the LP group and interstitial fibrosis was marginally reduced. Glomerular hypertrophy, glomerular sclerosis, tubular dilatation, leucocyte infiltration, adhesion molecule expression and TGF-beta1 mRNA expression were similarly increased in both groups. Thus, reducing dietary protein to 8% lowered urinary protein, but did not significantly affect the development of chronic rejection in renal allografts beyond affording a degree of protection from tubulointerstitial damage.

Annual Research Briefs, 1992

NASA Technical Reports Server (NTRS)

Spinks, Debra (Compiler)

1993-01-01

This report contains the 1992 annual progress reports of the Research Fellows and students of the Center for Turbulence Research. Considerable effort was focused on the large eddy simulation technique for computing turbulent flows. This increased activity has been inspired by the recent predictive successes of the dynamic subgrid scale modeling procedure which was introduced during the 1990 Summer Program. Several Research Fellows and students are presently engaged in both the development of subgrid scale models and their applications to complex flows. The first group of papers in this report contain the findings of these studies. They are followed by reports grouped in the general areas of modeling, turbulence physics, and turbulent reacting flows. The last contribution in this report outlines the progress made on the development of the CTR post-processing facility.

Probabilistic information transmission in a network of coupled oscillators reveals speed-accuracy trade-off in responding to threats

PubMed Central

Chicoli, Amanda; Paley, Derek A.

2016-01-01

Individuals in a group may obtain information from other group members about the environment, including the location of a food source or the presence of a predator. Here, we model how information spreads in a group using a susceptible-infected-removed epidemic model. We apply this model to a simulated shoal of fish using the motion dynamics of a coupled oscillator model, in order to test the biological hypothesis that polarized or aligned shoaling leads to faster and more accurate escape responses. The contributions of this study are the (i) application of a probabilistic model of epidemics to the study of collective animal behavior; (ii) testing the biological hypothesis that group cohesion improves predator escape; (iii) quantification of the effect of social cues on startle propagation; and (iv) investigation of the variation in response based on network connectivity. We find that when perfectly aligned individuals in a group are startled, there is a rapid escape by individuals that directly detect the threat, as well as by individuals responding to their neighbors. However, individuals that are not startled do not head away from the threat. In startled groups that are randomly oriented, there is a rapid, accurate response by individuals that directly detect the threat, followed by less accurate responses by individuals responding to neighbor cues. Over the simulation duration, however, even unstartled individuals head away from the threat. This study illustrates a potential speed-accuracy trade-off in the startle response of animal groups, in agreement with several previous experimental studies. Additionally, the model can be applied to a variety of group decision-making processes, including those involving higher-dimensional motion. PMID:27907996

Probabilistic information transmission in a network of coupled oscillators reveals speed-accuracy trade-off in responding to threats

NASA Astrophysics Data System (ADS)

Chicoli, Amanda; Paley, Derek A.

2016-11-01

Individuals in a group may obtain information from other group members about the environment, including the location of a food source or the presence of a predator. Here, we model how information spreads in a group using a susceptible-infected-removed epidemic model. We apply this model to a simulated shoal of fish using the motion dynamics of a coupled oscillator model, in order to test the biological hypothesis that polarized or aligned shoaling leads to faster and more accurate escape responses. The contributions of this study are the (i) application of a probabilistic model of epidemics to the study of collective animal behavior; (ii) testing the biological hypothesis that group cohesion improves predator escape; (iii) quantification of the effect of social cues on startle propagation; and (iv) investigation of the variation in response based on network connectivity. We find that when perfectly aligned individuals in a group are startled, there is a rapid escape by individuals that directly detect the threat, as well as by individuals responding to their neighbors. However, individuals that are not startled do not head away from the threat. In startled groups that are randomly oriented, there is a rapid, accurate response by individuals that directly detect the threat, followed by less accurate responses by individuals responding to neighbor cues. Over the simulation duration, however, even unstartled individuals head away from the threat. This study illustrates a potential speed-accuracy trade-off in the startle response of animal groups, in agreement with several previous experimental studies. Additionally, the model can be applied to a variety of group decision-making processes, including those involving higher-dimensional motion.

Probabilistic information transmission in a network of coupled oscillators reveals speed-accuracy trade-off in responding to threats.

PubMed

Chicoli, Amanda; Paley, Derek A

2016-11-01

Individuals in a group may obtain information from other group members about the environment, including the location of a food source or the presence of a predator. Here, we model how information spreads in a group using a susceptible-infected-removed epidemic model. We apply this model to a simulated shoal of fish using the motion dynamics of a coupled oscillator model, in order to test the biological hypothesis that polarized or aligned shoaling leads to faster and more accurate escape responses. The contributions of this study are the (i) application of a probabilistic model of epidemics to the study of collective animal behavior; (ii) testing the biological hypothesis that group cohesion improves predator escape; (iii) quantification of the effect of social cues on startle propagation; and (iv) investigation of the variation in response based on network connectivity. We find that when perfectly aligned individuals in a group are startled, there is a rapid escape by individuals that directly detect the threat, as well as by individuals responding to their neighbors. However, individuals that are not startled do not head away from the threat. In startled groups that are randomly oriented, there is a rapid, accurate response by individuals that directly detect the threat, followed by less accurate responses by individuals responding to neighbor cues. Over the simulation duration, however, even unstartled individuals head away from the threat. This study illustrates a potential speed-accuracy trade-off in the startle response of animal groups, in agreement with several previous experimental studies. Additionally, the model can be applied to a variety of group decision-making processes, including those involving higher-dimensional motion.

Stochastic Frontier Model Approach for Measuring Stock Market Efficiency with Different Distributions

PubMed Central

Hasan, Md. Zobaer; Kamil, Anton Abdulbasah; Mustafa, Adli; Baten, Md. Azizul

2012-01-01

The stock market is considered essential for economic growth and expected to contribute to improved productivity. An efficient pricing mechanism of the stock market can be a driving force for channeling savings into profitable investments and thus facilitating optimal allocation of capital. This study investigated the technical efficiency of selected groups of companies of Bangladesh Stock Market that is the Dhaka Stock Exchange (DSE) market, using the stochastic frontier production function approach. For this, the authors considered the Cobb-Douglas Stochastic frontier in which the technical inefficiency effects are defined by a model with two distributional assumptions. Truncated normal and half-normal distributions were used in the model and both time-variant and time-invariant inefficiency effects were estimated. The results reveal that technical efficiency decreased gradually over the reference period and that truncated normal distribution is preferable to half-normal distribution for technical inefficiency effects. The value of technical efficiency was high for the investment group and low for the bank group, as compared with other groups in the DSE market for both distributions in time- varying environment whereas it was high for the investment group but low for the ceramic group as compared with other groups in the DSE market for both distributions in time-invariant situation. PMID:22629352

Stochastic frontier model approach for measuring stock market efficiency with different distributions.

PubMed

Hasan, Md Zobaer; Kamil, Anton Abdulbasah; Mustafa, Adli; Baten, Md Azizul

2012-01-01

The stock market is considered essential for economic growth and expected to contribute to improved productivity. An efficient pricing mechanism of the stock market can be a driving force for channeling savings into profitable investments and thus facilitating optimal allocation of capital. This study investigated the technical efficiency of selected groups of companies of Bangladesh Stock Market that is the Dhaka Stock Exchange (DSE) market, using the stochastic frontier production function approach. For this, the authors considered the Cobb-Douglas Stochastic frontier in which the technical inefficiency effects are defined by a model with two distributional assumptions. Truncated normal and half-normal distributions were used in the model and both time-variant and time-invariant inefficiency effects were estimated. The results reveal that technical efficiency decreased gradually over the reference period and that truncated normal distribution is preferable to half-normal distribution for technical inefficiency effects. The value of technical efficiency was high for the investment group and low for the bank group, as compared with other groups in the DSE market for both distributions in time-varying environment whereas it was high for the investment group but low for the ceramic group as compared with other groups in the DSE market for both distributions in time-invariant situation.

A Grass-Roots Endeavor To Develop a Permanent University Program for Vision Professionals: The North Carolina Model.

ERIC Educational Resources Information Center

Walker, Brad R.; Bozeman, Laura A.

2002-01-01

This article describes a collaborative process that parents, teachers, consumers, and advocacy groups in North Carolina used to successfully establish a permanently funded university training program specializing in visual impairments, the Visual Impairment Training Program. Within this process several factors were identified that contributed to…

South African Teachers' Ability to Argue: The Emergence of Inclusive Argumentation

ERIC Educational Resources Information Center

Scholtz, Zena; Braund, Martin; Hodges, Merle; Koopman, Robert; Lubben, Fred

2008-01-01

This paper explores the argumentation ability of ten science teachers in two South African schools on opposite ends of the resource spectrum. Toulmin's model is used to analyse individual contributions in six group discussions. The findings show that levels of argumentation improve with teachers' involvement in the development of teaching…

Everyone Is on Welfare: "The Role of Redistribution in Social Policy" Revisited.

ERIC Educational Resources Information Center

Abramovitz, Mimi

1983-01-01

Uses Titmuss's model of three welfare systems to analyze how the rapidly expanding system of tax benefits available to middle- and upper-income groups parallels the social welfare system for the poor. Operating as a shadow welfare state, the tax benefits system contributes to the upward redistribution of income. (Author/JAC)

John Langstaff: Community Musician and Reveler

ERIC Educational Resources Information Center

Bartolome, Sarah J.; Campbell, Patricia Shehan

2009-01-01

John Langstaff fits within a select group of pathfinders in American music education who have shaped the profession's service to schools and society with special attention to the traditional musical expressions of American folk. His life and works are worthy of study for the contributions he made as a singer who modelled the nuances of traditional…

A THEORETICAL MODEL FOR RESEARCH IN EDUCATION.

ERIC Educational Resources Information Center

ARMSTRONG, JENNY R.

THE FAILURE OF EDUCATIONAL RESEARCH TO CONTRIBUTE LARGE CONSISTENT BODIES OF KNOWLEDGE ABOUT THE EDUCATIONAL PROCESS HAS BEEN DUE TO FIVE MAJOR FACTORS--(1) FAULTY EXPERIMENTAL DESIGN, (2) FAILURE TO CONSIDER ALL OF THE MAJOR INPUT ELEMENTS OF THE EDUCATIONAL PROCESS, (3) FAILURE TO MAKE MEANINGFUL COMPARISONS (FOR EXAMPLE THE CONTROL GROUP IS NOT…

A Challenge for Social Studies Educators: Increasing Civility in Schools and Society by Modeling Civic Virtues

ERIC Educational Resources Information Center

Moore, James

2012-01-01

Many scholars, teachers, parents, as well as others, are concerned with the decline of civility in public discourse and public schools. The sharp differences among various ideological groups, exacerbated by media incivility, are contributing factors to rising incivility. This ideological divide currently manifests itself in bitter partisan…

Structured Parent Education in the Management of Childhood Atopic Dermatitis: The Berlin Model.

ERIC Educational Resources Information Center

Wenninger, Kerstin; Kehrt, Rainer; von Ruden, Ursula; Lehmann, Christine; Binder, Christiane; Wahn, Ulrich; Staab, Doris

2000-01-01

Describes the goals and content of the Berlin education program for parents and children with atopic dermatitis (AD). Program included six group sessions concerning medical, nutritional, and psychological issues. Program aimed to contribute towards a comprehensive, family-oriented management of childhood AD. Data showed the program had a positive…

"Between the Earth and the Skies" The Challenges to Catholic Institution-Building in Pennsylvania’s Croatian Communities, 1894-1924.

DTIC Science & Technology

1998-05-01

religious factors reveals points of divergence between their experience and that of other immigrant groups. An assimilation model developed by Silvano...Tomasi provides the framework for this comparison. The thesis concludes that several unique factors contributed to the anomalous religious

Individual Differences in Visual Word Recognition: Insights from the English Lexicon Project

ERIC Educational Resources Information Center

Yap, Melvin J.; Balota, David A.; Sibley, Daragh E.; Ratcliff, Roger

2012-01-01

Empirical work and models of visual word recognition have traditionally focused on group-level performance. Despite the emphasis on the prototypical reader, there is clear evidence that variation in reading skill modulates word recognition performance. In the present study, we examined differences among individuals who contributed to the English…

The effect of active learning on college students' achievement, motivation, and self-efficacy in a human physiology course for non-majors

NASA Astrophysics Data System (ADS)

Wilke, Roger Russell

2000-10-01

This study investigated the effects active learning strategies had on college students' achievement, motivation, and self-efficacy, in a human physiology course for non-majors. A continuum-based active learning instructional model was implemented over the course of a semester to assess the effects on the variables and specific student outcomes of learning mentioned above. In addition analyses were conducted to explore what learner characteristics contributed to the successful implementation of the model such as students' gender, classification, major, grade point average, ACT and SAT scores, motivation, and self-efficacy. A quasi-experimental, Solomon-4 Group design was undertaken on 171 students in a small west-Texas university. Treatment groups were taught using the model while controls were taught using traditional lecture methods. Students were administered a comprehensive physiology content exam, sections of the Motivated Strategies for Learning Questionnaire, and attitude surveys to assess the effects of the continuum-based active learning strategies. Factorial analyses indicated the treatment group acquired significantly more content knowledge and were significantly more self-efficacious than students in the control group. There were no significant differences in motivation. Factorial and modified regression analyses in the aptitude by treatment interaction exploration determined that males in the treatment group performed significantly better on the comprehensive physiology content exam versus males in the control group. While females performed better overall than males, there were no significant differences in achievement between females in the treatment group and those in the control. No significant interactions were found for the other learner characteristics. The results also indicated that students' general cognitive ability as measured by their grade point average, ACT, and SAT scores and their self-efficacy contributed significantly to their achievement. Attitude surveys indicated that students in both the treatment and control groups demonstrated a positive attitude toward active learning, believed it helped them to learn the material, and would choose an active learning course in the future if given the opportunity. This study demonstrated that continuum-based active learning strategies used in this context, improved students' content acquisition and self-efficacy and had wide applicability with a number of learner characteristics.

Royal jelly and bee pollen decrease bone loss due to osteoporosis in an oophorectomized rat model.

PubMed

Kafadar, Ibrahim Halil; Güney, Ahmet; Türk, Cemil Yildirim; Oner, Mithat; Silici, Sibel

2012-01-01

In this study, we aimed to investigate whether royal jelly and bee pollen reduce the bone loss due to osteoporosis in oophorectomized rat model. Thirty-two female Sprague-Dawley mature rats at six-month-old, weighing 180-260 g were used in the study. The rats were divided into four groups: Sham-operation group, only oophorectomy group, oophorectomy in combination with royal jelly group, and oophorectomy and bee pollen group. The rats were sacrified within 12 weeks following surgery. Bone mineral density (BMD) was measured and blood samples were collected for biochemical analysis before sacrification. Following sacrification, uterine weights were measured and tissue samples were taken to determine bone calcium and phosphate level with imaging through scanning electron microscope. The uterine weights of the rats were found higher in Sham-operation group than the other groups. The difference among the groups was statistically significant (p=0.001). Total body BMD results were similar in all groups and there was not statistically significant difference (p=0.19). The lumbar spine and proximal femur BMD results were statistically significantly higher in the royal jelly and bee pollen groups, compared to only oophorectomy group (p=0.001). Bone tissue calcium and phosphate levels were higher in royal jelly and bee pollen groups. Royal jelly and bee pollen decrease the bone loss due to osteoporosis in oophorectomized rat model. These results may contribute to the clinical practice.

Roles of functional groups of naproxen in its sorption to kaolinite.

PubMed

Yu, Chenglong; Bi, Erping

2015-11-01

The sorption of acidic anti-inflammatory drugs to soils is important for evaluating their fate and transformations in the water-soil environment. However, roles of functional groups of ionisable drugs onto mineral surfaces have not been sufficiently studied. In this study, batch experiments of naproxen (NPX, anti-inflammatory drug) and two kinds of competitors to kaolinite were studied. The Kd of naproxen to kaolinite is 1.30-1.62 L kg(-1). The n-π electron donor-acceptor (n-π EDA) interaction between diaromatic ring of naproxen (π-electron acceptors) and the siloxane oxygens (n-donors) of kaolinite is the dominant sorption mechanism. The carboxyl group of naproxen can contribute to the overall sorption. A conception model was put forward to elucidate to sorption mechanisms, in which the contribution of n-π EDA and hydrogen bond to overall sorption was quantified. These sorption mechanisms can be helpful for estimating the fate and mobility of acid pharmaceuticals in soil-water environment. Copyright © 2015 Elsevier Ltd. All rights reserved.

Modelling of additive manufacturing processes: a review and classification

NASA Astrophysics Data System (ADS)

Stavropoulos, Panagiotis; Foteinopoulos, Panagis

2018-03-01

Additive manufacturing (AM) is a very promising technology; however, there are a number of open issues related to the different AM processes. The literature on modelling the existing AM processes is reviewed and classified. A categorization of the different AM processes in process groups, according to the process mechanism, has been conducted and the most important issues are stated. Suggestions are made as to which approach is more appropriate according to the key performance indicator desired to be modelled and a discussion is included as to the way that future modelling work can better contribute to improving today's AM process understanding.

Modelling inflation in transportation, comunication and financial services using B-Spline time series model

NASA Astrophysics Data System (ADS)

Suparti; Prahutama, Alan; Santoso, Rukun

2018-05-01

Inflation is an increase in the price of goods and services in general where the goods and services are the basic needs of society or the decline of the selling power of a country’s currency. Significant inflationary increases occurred in 2013. This increase was contributed by a significant increase in some inflation sectors / groups i.e transportation, communication and financial services; the foodstuff sector, and the housing, water, electricity, gas and fuel sectors. However, significant contributions occurred in the transportation, communications and financial services sectors. In the model of IFIs in the transportation, communication and financial services sector use the B-Spline time series approach, where the predictor variable is Yt, whereas the predictor is a significant lag (in this case Yt-1). In modeling B-spline time series determined the order and the optimum knot point. Optimum knot determination using Generalized Cross Validation (GCV). In inflation modeling for transportation sector, communication and financial services obtained model of B-spline order 2 with 2 points knots produce MAPE less than 50%.

Recollection and familiarity in hippocampal amnesia.

PubMed

Turriziani, Patrizia; Serra, Laura; Fadda, Lucia; Caltagirone, Carlo; Carlesimo, Giovanni Augusto

2008-01-01

Currently, there is a general agreement that two distinct cognitive operations, recollection and familiarity, contribute to performance on recognition memory tests. However, there is a controversy about whether recollection and familiarity reflect different memory processes, mediated by distinct neural substrates (dual-process models), or whether they are the expression of memory traces of different strength in the context of a unitary declarative memory system (unitary-strength models). Critical in this debate is the status of recognition memory in hippocampal amnesia and, in particular, whether the various structures in the medial temporal lobe (MTL) contribute differentially to the recollection and familiarity components of recognition. The present study aimed to explore the relative contribution of recollection and familiarity to recognition of words that had been previously read or that had been previously generated in a group of severely amnesic patients with cerebral damage restricted to the hippocampus. A convergent pattern of results emerged when we used a subjective-based (remember/know; R/K) and an objective-based (process dissociation procedure; PDP) methods to estimate the contribution of recollection and familiarity to recognition performance. In both PDP and R/K procedures, healthy controls disclosed significantly higher recollection estimates for words that had been anagrammed than for words that had been read. Amnesic patients' recollection scores were not different for words that had been generated or that had been read, and the recollection estimate for words that had been generated was significantly reduced as compared to the group of healthy controls. For familiarity, both healthy controls and amnesic patients recognized as familiar more words that had been generated than words that had been read, and there was no difference between the two groups. These data support the hypothesis of a specific role of the hippocampus in recollection processes and suggest that other components of the MTL (e.g., perirhinal cortex) may be more involved in the process of familiarity. 2008 Wiley-Liss, Inc.

Introducing consultant outpatient clinics to community settings to improve access to paediatrics: an observational impact study.

PubMed

McLeod, Hugh; Heath, Gemma; Cameron, Elaine; Debelle, Geoff; Cummins, Carole

2015-06-01

In line with a national policy to move care 'closer to home', a specialist children's hospital in the National Health Service in England introduced consultant-led 'satellite' clinics to two community settings for general paediatric outpatient services. Objectives were to reduce non-attendance at appointments by providing care in more accessible locations and to create new physical clinic capacity. This study evaluated these satellite clinics to inform further development and identify lessons for stakeholders. Impact of the satellite clinics was assessed by comparing community versus hospital-based clinics across the following measures: (1) non-attendance rates and associated factors (including patient characteristics and travel distance) using a logistic regression model; (2) percentage of appointments booked within local catchment area; (3) contribution to total clinic capacity; (4) time allocated to clinics and appointments; and (5) clinic efficiency, defined as the ratio of income to staff-related costs. Satellite clinics did not increase attendance beyond their contribution to shorter travel distance, which was associated with higher attendance. Children living in the most-deprived areas were 1.8 times more likely to miss appointments compared with those from least-deprived areas. The satellite clinics' contribution to activity in catchment areas and to total capacity was small. However, one of the two satellite clinics was efficient compared with most hospital-based clinics. Outpatient clinics were relocated in pragmatically chosen community settings using a 'drag and drop' service model. Such clinics have potential to improve access to specialist paediatric healthcare, but do not provide a panacea. Work is required to improve attendance as part of wider efforts to support vulnerable families. Satellite clinics highlight how improved management could contribute to better use of existing capacity. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Evaluating gull diets: A comparison of conventional methods and stable isotope analysis

USGS Publications Warehouse

Weiser, Emily L.; Powell, Abby N.

2011-01-01

Samples such as regurgitated pellets and food remains have traditionally been used in studies of bird diets, but these can produce biased estimates depending on the digestibility of different foods. Stable isotope analysis has been developed as a method for assessing bird diets that is not biased by digestibility. These two methods may provide complementary or conflicting information on diets of birds, but are rarely compared directly. We analyzed carbon and nitrogen stable isotope ratios of feathers of Glaucous Gull (Larus hyperboreus) chicks from eight breeding colonies in northern Alaska, and used a Bayesian mixing model to generate a probability distribution for the contribution of each food group to diets. We compared these model results with probability distributions from conventional diet samples (pellets and food remains) from the same colonies and time periods. Relative to the stable isotope estimates, conventional analysis often overestimated the contributions of birds and small mammals to gull diets and often underestimated the contributions of fish and zooplankton. Both methods gave similar estimates for the contributions of scavenged caribou, miscellaneous marine foods, and garbage to diets. Pellets and food remains therefore may be useful for assessing the importance of garbage relative to certain other foods in diets of gulls and similar birds, but are clearly inappropriate for estimating the potential impact of gulls on birds, small mammals, or fish. However, conventional samples provide more species-level information than stable isotope analysis, so a combined approach would be most useful for diet analysis and assessing a predator's impact on particular prey groups.

Predicting mortality over different time horizons: which data elements are needed?

PubMed

Goldstein, Benjamin A; Pencina, Michael J; Montez-Rath, Maria E; Winkelmayer, Wolfgang C

2017-01-01

Electronic health records (EHRs) are a resource for "big data" analytics, containing a variety of data elements. We investigate how different categories of information contribute to prediction of mortality over different time horizons among patients undergoing hemodialysis treatment. We derived prediction models for mortality over 7 time horizons using EHR data on older patients from a national chain of dialysis clinics linked with administrative data using LASSO (least absolute shrinkage and selection operator) regression. We assessed how different categories of information relate to risk assessment and compared discrete models to time-to-event models. The best predictors used all the available data (c-statistic ranged from 0.72-0.76), with stronger models in the near term. While different variable groups showed different utility, exclusion of any particular group did not lead to a meaningfully different risk assessment. Discrete time models performed better than time-to-event models. Different variable groups were predictive over different time horizons, with vital signs most predictive for near-term mortality and demographic and comorbidities more important in long-term mortality. © The Author 2016. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

CROSS-DISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY: Evolutionary Self-Questioning Games with Local Contribution

NASA Astrophysics Data System (ADS)

Liu, Yong-Kui; Li, Zhi; Chen, Xiao-Jie; Wang, Long

2009-08-01

We investigate the evolutionary Prisoner's Dilemma and the Snowdrift Game on small-world networks in a realistic social context where individuals consider their local contributions to their group and update their strategies by self-questioning. An individual with introspection can determine whether its current strategy is superior by playing a virtual round of the game and its local contribution is defined as the sum of all the payoffs its neighbors collect against it. In our model, the performance of an individual is determined by both its payoff and local contribution through a linear combination. We demonstrate that the present mechanism can produce very robust cooperative behavior in both games. Furthermore, we provide theoretical analysis based on mean-field approximation, and find that the analytical predictions are qualitatively consistent with the simulation results.

High-School Chemistry Students' Performance and Gender Differences in a Computerized Molecular Modeling Learning Environment

NASA Astrophysics Data System (ADS)

Barnea, Nitza; Dori, Yehudit J.

1999-12-01

Computerized molecular modeling (CMM) contributes to the development of visualization skills via vivid animation of three dimensional representations. Its power to illustrate and explore phenomena in chemistry teaching stems from the convenience and simplicity of building molecules of any size and color in a number of presentation styles. A new CMM-based learning environment for teaching and learning chemistry in Israeli high schools has been designed and implemented. Three tenth grade experimental classes used this discovery CMM approach, while two other classes, who studied the same topic in the customary approach, served as a control group. We investigated the effects of using molecular modeling on students' spatial ability, understanding of new concepts related to geometric and symbolic representations and students' perception of the model concept. Each variable was examined for gender differences. Students of the experimental group performed better than control group students in all three performance aspects. Experimental group students scored higher than the control group students in the achievement test on structure and bonding. Students' spatial ability improved in both groups, but students from the experimental group scored higher. For the average students in the two groups the improvement in all three spatial ability sub-tests —paper folding, card rotation, and cube comparison—was significantly higher for the experimental group. Experimental group students gained better insight into the model concept than the control group and could explain more phenomena with the aid of a variety of models. Hence, CMM helps in particular to improve the examined cognitive aspects of the average student population. In most of the achievement and spatial ability tests no significant differences between the genders were found, but in some aspects of model perception and verbal argumentation differences still exist. Experimental group females improved their model perception more than the control group females in understanding ways to create models and in the role of models as mental structures and prediction tools. Teachers' and students' feedback on the CMM learning environment was found to be positive, as it helped them understand concepts in molecular geometry and bonding. The results of this study suggest that teaching/learning of topics in chemistry that are related to three dimensional structures can be improved by using a discovery approach in a computerized learning environment.

Rfam: Wikipedia, clans and the “decimal” release

PubMed Central

Gardner, Paul P.; Daub, Jennifer; Tate, John; Moore, Benjamin L.; Osuch, Isabelle H.; Griffiths-Jones, Sam; Finn, Robert D.; Nawrocki, Eric P.; Kolbe, Diana L.; Eddy, Sean R.; Bateman, Alex

2011-01-01

The Rfam database aims to catalogue non-coding RNAs through the use of sequence alignments and statistical profile models known as covariance models. In this contribution, we discuss the pros and cons of using the online encyclopedia, Wikipedia, as a source of community-derived annotation. We discuss the addition of groupings of related RNA families into clans and new developments to the website. Rfam is available on the Web at http://rfam.sanger.ac.uk. PMID:21062808

EAS fluctuation approach to primary mass composition investigation

NASA Technical Reports Server (NTRS)

Stamenov, J. N.; Janminchev, V. D.

1985-01-01

The analysis of muon and electron fluctuation distribution shapes by statistical method of invers problem solution gives the possibility to obtain the relative contribution values of the five main primary nuclei groups. The method is model-independent for a big class of interaction models and can give good results for observation levels not too far from the development maximum and for the selection of showers with fixed sizes and zenith angles not bigger than 30 deg.

The effect of a rehabilitation nursing intervention model on improving the comprehensive health status of patients with hand burns.

PubMed

Li, Lin; Dai, Jia-Xi; Xu, Le; Huang, Zhen-Xia; Pan, Qiong; Zhang, Xi; Jiang, Mei-Yun; Chen, Zhao-Hong

2017-06-01

To observe the effect of a rehabilitation intervention on the comprehensive health status of patients with hand burns. Most studies of hand-burn patients have focused on functional recovery. There have been no studies involving a biological-psychological-social rehabilitation model of hand-burn patients. A randomized controlled design was used. Patients with hand burns were recruited to the study, and sixty patients participated. Participants were separated into two groups: (1) The rehabilitation intervention model group (n=30) completed the rehabilitation intervention model, which included the following measures: enhanced social support, intensive health education, comprehensive psychological intervention, and graded exercise. (2) The control group (n=30) completed routine treatment. Intervention lasted 5 weeks. Analysis of variance (ANOVA) and Student's t test were conducted. The rehabilitation intervention group had significantly better scores than the control group for comprehensive health, physical function, psychological function, social function, and general health. The differences between the index scores of the two groups were statistically significant. The rehabilitation intervention improved the comprehensive health status of patients with hand burns and has favorable clinical application. The comprehensive rehabilitation intervention model used here provides scientific guidance for medical staff aiming to improve the integrated health status of hand-burn patients and accelerate their recovery. What does this paper contribute to the wider global clinical community? Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Providing open access data online to advance malaria research and control.

PubMed

Moyes, Catherine L; Temperley, William H; Henry, Andrew J; Burgert, Clara R; Hay, Simon I

2013-05-16

To advance research on malaria, the outputs from existing studies and the data that fed into them need to be made freely available. This will ensure new studies can build on the work that has gone before. These data and results also need to be made available to groups who are developing public health policies based on up-to-date evidence. The Malaria Atlas Project (MAP) has collated and geopositioned over 50,000 parasite prevalence and vector occurrence survey records contributed by over 3,000 sources including research groups, government agencies and non-governmental organizations worldwide. This paper describes the results of a project set up to release data gathered, used and generated by MAP. Requests for permission to release data online were sent to 236 groups who had contributed unpublished prevalence (parasite rate) surveys. An online explorer tool was developed so that users can visualize the spatial distribution of the vector and parasite survey data before downloading it. In addition, a consultation group was convened to provide advice on the mode and format of release for data generated by MAP's modelling work. New software was developed to produce a suite of publication-quality map images for download from the internet for use in external publications. More than 40,000 survey records can now be visualized on a set of dynamic maps and downloaded from the MAP website on a free and unrestricted basis. As new data are added and new permissions to release existing data come in, the volume of data available for download will increase. The modelled data output from MAP's own analyses are also available online in a range of formats, including image files and GIS surface data, for use in advocacy, education, further research and to help parameterize or validate other mathematical models.

Making patient and public involvement in cancer and palliative research a reality: academic support is vital for success.

PubMed

Collins, Karen; Boote, Jonathan; Ardron, David; Gath, Jacqui; Green, Tracy; Ahmedzai, Sam H

2015-06-01

Patient and public involvement (PPI) has become an established theme within the UK health research policy and is recognised as an essential force in the drive to improve the quality of services and research. These developments have been particularly rapid in the cancer field. This paper outlines a model of PPI in research (known as the North Trent Cancer Research Network Consumer Research Panel, NTCRN CRP; comprising 38 cancer and palliative care patients/carers) and the key benefits and challenges to effective PPI in cancer research. The PPI model has become a sustainable, inclusive and effective way of implementing PPI within the cancer context. Challenges include (1) a lack of time and funding available to support the PPI model; (2) tensions between different stakeholder groups when developing and conducting health research; (3) panel members finding it difficult to effectively integrate into research meetings when their role and contribution is not made clear at the outset or when unfamiliar language and jargon are used and not explained; (4) some professionals remain unclear about the role and practical implications of PPI in research. However, notwithstanding its financial and organisational challenges, the way that the NTCRN CRP is supported has provided a solid base for it to flourish. PPI provides considerable opportunities for patients and the public to work collaboratively with professionals to influence the cancer research agenda, with the contribution of PPI to the research process being integral to the entire process from the outset, rather than appended to it. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Are there common familial influences for major depressive disorder and an overeating-binge eating dimension in both European American and African American female twins?

PubMed

Munn-Chernoff, Melissa A; Grant, Julia D; Agrawal, Arpana; Koren, Rachel; Glowinski, Anne L; Bucholz, Kathleen K; Madden, Pamela A F; Heath, Andrew C; Duncan, Alexis E

2015-05-01

Although prior studies have demonstrated that depression is associated with an overeating-binge eating dimension (OE-BE) phenotypically, little research has investigated whether familial factors contribute to the co-occurrence of these phenotypes, especially in community samples with multiple racial/ethnic groups. We examined the extent to which familial (i.e., genetic and shared environmental) influences overlapped between Major Depressive Disorder (MDD) and OE-BE in a population-based sample and whether these influences were similar across racial/ethnic groups. Participants included 3,226 European American (EA) and 550 African American (AA) young adult women from the Missouri Adolescent Female Twin Study. An adaptation of the Semi-Structured Assessment for the Genetics of Alcoholism (SSAGA) was administered to assess lifetime DSM-IV MDD and OE-BE. Quantitative genetic modeling was used to estimate familial influences between both phenotypes; all models controlled for age. The best-fitting model, which combined racial/ethnic groups, found that additive genetic influences accounted for 44% (95% CI: 34%, 53%) of the MDD variance and 40% (25%, 54%) for OE-BE, with the remaining variances due to non-shared environmental influences. Genetic overlap was substantial (rg  = .61 [.39, .85]); non-shared environmental influences on MDD and OE-BE overlapped weakly (re  = .26 [.09, .42]). Results suggest that common familial influences underlie MDD and OE-BE, and the magnitude of familial influences contributing to the comorbidity between MDD and OE-BE is similar between EA and AA women. If racial/ethnic differences truly exist, then larger sample sizes may be needed to fully elucidate familial risk for comorbid MDD and OE-BE across these groups. © 2014 Wiley Periodicals, Inc.

Are There Common Familial Influences for Major Depressive Disorder and an Overeating-Binge Eating Dimension in both European-American and African-American Female Twins?

PubMed Central

Munn-Chernoff, Melissa A.; Grant, Julia D.; Agrawal, Arpana; Koren, Rachel; Glowinski, Anne L.; Bucholz, Kathleen K.; Madden, Pamela A. F.; Heath, Andrew C.; Duncan, Alexis E.

2014-01-01

Objective Although prior studies have demonstrated that depression is associated with an overeating-binge eating dimension (OE-BE), phenotypically, little research has investigated whether familial factors contribute to the co-occurrence of these phenotypes, especially in community samples with multiple racial/ethnic groups. We examined the extent to which familial (i.e., genetic and shared environmental) influences overlapped between Major Depressive Disorder (MDD) and OE-BE in a population-based sample and whether these influences were similar across racial/ethnic groups Method Participants included 3226 European-American (EA) and 550 African-American (AA) young adult women from the Missouri Adolescent Female Twin Study. An adaptation of the Semi-Structured Assessment for the Genetics of Alcoholism (SSAGA) was administered to assess lifetime DSM-IV MDD and OE-BE. Quantitative genetic modeling was used to estimate familial influences between both phenotypes; all models controlled for age. Results The best-fitting model, which combined racial/ethnic groups, found that additive genetic influences accounted for 44% (95% CI: 34%, 53%) of the MDD variance and 40% (25%, 54%) for OE-BE, with the remaining variances due to non-shared environmental influences. Genetic overlap was substantial (rg = .61 [.39, .85]); non-shared environmental influences on MDD and OE-BE overlapped weakly (re = .26 [.09, .42]) Discussion Results suggest that common familial influences underlie MDD and OE-BE, and the magnitude of familial influences contributing to the comorbidity between MDD and OE-BE is similar between EA and AA women. If racial/ethnic differences truly exist, then larger sample sizes may be needed to fully elucidate familial risk for comorbid MDD and OE-BE across these groups. PMID:24659561

[Effects of acupuncture on bone metabolism and serum estradiol level in ovariectomy-induced osteoporosis rats].

PubMed

Ma, Jie; Yun-guang, Hu; Zhang, Da-hui

2008-08-01

To observe the effect of acupuncture (Acu) on bone metabolism and serum estradiol (E2) in ovariectomized (OVX) rats for studying its underlying mechanism in treating osteoporosis. Forty female SD rats of six months were randomized into sham operation (sham), model, Acu and Diethylstibestrol (DES) groups, with 10 cases in each. Postmenopausal osteoporosis model was established by removing ovaries under anesthesia. In Acu group, bilateral "Dazhu" (BL 11), "Shenshu" (BL 23) and "Pishu" (BL 20) were punctured and stimulated for 30 minutes, once daily for 60 days. Rats of DES group were drenched with saline+DES (22.5 microg/ml) 1 ml/100 g, once daily for 60 days. At the end of experiments, blood samples were collected from femoral artery for assaying serum alkaline phosphatase (ALP), tartrate-resistant acid phosphatase (TRAP) contents by using biochemistry, and serum bone gla protein (BGP) and E2 levels by immunoradioassay. Compared with sham group, uterus wet weight, serum E2 content in model group decreased significantly (P < 0.01) while body weight, serum ALP, BGP and TRAP levels in model group increased significantly (P < 0.01, 0.05). Compared with model group, uterus wet weight and serum Ez content in Acu and DES groups increased significantly (P < 0.01); while body weight, serum ALP, BGP and TRAP levels decreased considerably (P < 0.01). No significant differences were found between Acu and DES groups in serum E2, ALP, BGP and TRAP levels (P > 0.05). Acupuncture can suppress abnormal increase of body weight and decrease of serum E2 level, and significantly downregulate serum ALP, BGP and TRAP levels in OVX rats, which may contribute to its effect in relieving osteoporosis.

[Effects of electroacupuncture of "Sanyinjiao" (SP 6) on contents of MDA and beta-EP, and expression of HSP 70 in the uterus in rats with dysmenorrhea].

PubMed

Song, Xiao-Lin; Zhang, Lu-Fen; Li, Xiao-Hong; Xu, Li-Li; Li, Chun-Hua; Ding, Xi-Yan; Ren, Xiao-Xuan; Zhao, Ya-Fang; Guo, Meng-Wei; Sun, Zhi-Fang; Zhu, Jiang

2010-10-01

To investigate the effect of electroacupuncture (EA) of "Sanyinjiao" (SP 6) on the uterus in dysmenorrhea rats so as to study its underlying analgesic mechanism. A total of 48 SD rats during diestrus were randomized into normal saline (control) group, model group and acupuncture group according to a random number table, with 16 rats in each group. Dysmenorrhea model was established by subcutaneous injection of Estradiol benzoate (0.5 mg/d on the 1st and 10th day, and 0.2 mg/d from day 2 to day 9, once daily for 10 days) and oxytocin (2 U/rat, once on day 10). Malondialdehyde (MDA) and beta-endorphin (beta-EP) contents in the uterus were detected by radioimmunoassay, and the heat shock protein 70 (HSP 70) immunoactivity of the uterus was detected by immunohistochemistry. In comparison with the control group, MDA content in the uterus was increased significantly in the model group (P < 0.01), while the beta-EP level and the immunoactivity of HSP 70 immune-reaction (IR) positive products in the uterus decrease significantly (P < 0.01) and moderately, respectively in the model group. In comparison with the model group, uterine MDA content in the EA group was decreased significantly (P < 0.01), while uterine beta-EP level increased considerably (P < 0.01) and HSP 70 expression was upregulated to a certain degree. EA of "Sanyinjiao" (SP 6) can reduce MDA content and upregulate beta-EP level of the uterus in rats with dysmenorrhea, which may contribute to its analgesic effect in relieving dysmenorrhea by clearing away oxygen free radicals and raising analgesic substance in the uterus.

Understanding communication between emergency and consulting physicians: a qualitative study that describes and defines the essential elements of the emergency department consultation-referral process for the junior learner.

PubMed

Chan, Teresa; Orlich, Donika; Kulasegaram, Kulamakan; Sherbino, Jonathan

2013-01-01

To define the important elements of an emergency department (ED) consultation request and to develop a simple model of the process. From March to September 2010, 61 physicians (21 emergency medicine [EM], 20 general surgery [GS], 20 internal medicine [IM]; 31 residents, 30 attending staff) were questioned about how junior learners should be taught about ED consultation. Two investigators independently reviewed focus group and interview transcripts using grounded theory to generate an index of themes until saturation was reached. Disagreements were resolved by consensus, yielding an inventory of themes and subthemes. All transcripts were coded using this index of themes; 30% of transcripts were coded in duplicate to determine the agreement. A total of 245 themes and subthemes were identified. The agreement between reviewers was 77%. Important themes in the process were as follows: initial preparation and review of investigations by EM physician (overall endorsement 87% [range 70-100% in different groups]); identification of involved parties (patient and involved physicians) (100%); hypothesis of patient's diagnosis (75% [range 62-83%]) or question for the consulting physician (70% [range 55-95%]); urgency (100%) and stability (74% [range 62-80%]); questions from the consultant (100%); discussion/communication (98% [range 95-100%]); and feedback (98% [range 95-100%]). These components were reorganized into a simple framework (PIQUED). Each clinical specialty significantly contributed to the model (χ2  =  7.9; p value  =  0.019). Each group contributed uniquely to the final list of important elements (percent contributions: EM, 57%; GS, 41%; IM, 64%). We define important elements of an ED consultation with input from emergency and consulting physicians. We propose a model that organizes these elements into a simple framework (PIQUED) that may be valuable for junior learners.

Misbehaving macrophages in the pathogenesis of psoriasis.

PubMed

Clark, Rachael A; Kupper, Thomas S

2006-08-01

Psoriasis is a chronic inflammatory skin disease unique to humans. In this issue of the JCI, 2 studies of very different mouse models of psoriasis both report that macrophages play a key role in inducing psoriasis-like skin disease. Psoriasis is clearly a polygenic, inherited disease of uncontrolled cutaneous inflammation. The debate that currently rages in the field is whether psoriasis is a disease of autoreactive T cells or whether it reflects an intrinsic defect within the skin--or both. However, these questions have proven difficult to dissect using molecular genetic tools. In the current studies, the authors have used 2 different animal models to address the role of macrophages in disease pathogenesis: Wang et al. use a mouse model in which inflammation is T cell dependent, whereas the model used by Stratis et al. is T cell independent (see the related articles beginning on pages 2105 and 2094, respectively). Strikingly, both groups report an important contribution by macrophages, implying that macrophages can contribute to both epithelial-based and T cell-mediated pathways of inflammation.

Development of a claim review and payment model utilizing diagnosis related groups under the Korean health insurance.

PubMed

Shin, Y S; Yeom, Y K; Hwang, H

1993-02-01

This paper describes the development of a claim review and payment model utilizing the diagnosis related groups (DRGs) for the fee for service-based payment system of the Korean health insurance. The present review process, which examines all claims manually on a case-by-case basis, has been considered to be inefficient, costly, and time-consuming. Differences in case mix among hospitals are controlled in the proposed model using the Korean DRGs. They were developed by modifying the US-DRG system. An empirical test of the model indicated that it can enhance the efficiency as well as the credibility and objectivity of the claim review. Furthermore, it is expected that it can contribute effectively to medical cost containments and to optimal practice pattern of hospitals by establishing a useful mechanism in monitoring the performance of hospitals. However, the performance of this model needs to be upgraded by refining the Korean DRGs which play a key role in the model.

[Health Care Insurance in France: its impact on income distribution between age and social groups].

PubMed

Fourcade, N; Duval, J; Lardellier, R

2013-08-01

Our study, based on microsimulation models, evaluates the redistributive impact of health care insurance in France on income distribution between age and social groups. This work sheds light on the debate concerning the respective role of the public health care insurance (PHI) and the private supplemental health care insurance (SHI) in France. The analysis points out that the PHI enables the lowest-income households and the pensioners a better access to health care than they would have had under a complete private SHI. Due to the progressivity of taxes, low-income households contribute less to the PHI and get higher benefits because of a weaker health. Pensioners have low contributions to public health care finance but the highest health care expenditures. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Expertise finding in bibliographic network: topic dominance learning approach.

PubMed

Neshati, Mahmood; Hashemi, Seyyed Hadi; Beigy, Hamid

2014-12-01

Expert finding problem in bibliographic networks has received increased interest in recent years. This problem concerns finding relevant researchers for a given topic. Motivated by the observation that rarely do all coauthors contribute to a paper equally, in this paper, we propose two discriminative methods for realizing leading authors contributing in a scientific publication. Specifically, we cast the problem of expert finding in a bibliographic network to find leading experts in a research group, which is easier to solve. We recognize three feature groups that can discriminate relevant experts from other authors of a document. Experimental results on a real dataset, and a synthetic one that is gathered from a Microsoft academic search engine, show that the proposed model significantly improves the performance of expert finding in terms of all common information retrieval evaluation metrics.

The development of a model of community garden benefits to wellbeing.

PubMed

Egli, Victoria; Oliver, Melody; Tautolo, El-Shadan

2016-06-01

Community gardens contribute to community wellbeing by influencing the nutritional and social environment. The aim of this research was to develop a model that communicates the many benefits of community garden participation as described in the academic literature, to a diverse audience of laypersons. This model is an example of effective knowledge translation because the information is able to be more than simply understood but also practically applied. From April to August 2015, a model depicting the many benefits of community garden participation was prepared based on a global, critical literature review. The wellbeing benefits from community garden participation have been grouped into factors influencing the nutritional health environment and factors influencing the social environment. The graphic chosen to form the basis of the model is a fractal tree of life. In October 2015, to test the models comprehension and to obtain stakeholder feedback this model was presented to a diverse group of community members, leaders and workers from the Tāmaki region of Auckland, New Zealand. The model we present here effectively and clearly translates knowledge obtained from the academic literature on the benefits to wellbeing from community garden participation into a tool that can be used, adapted and developed by community groups, government agencies and health promoters.

Higgs decays to Z Z and Z γ in the standard model effective field theory: An NLO analysis

NASA Astrophysics Data System (ADS)

Dawson, S.; Giardino, P. P.

2018-05-01

We calculate the complete one-loop electroweak corrections to the inclusive H →Z Z and H →Z γ decays in the dimension-6 extension of the Standard Model Effective Field Theory (SMEFT). The corrections to H →Z Z are computed for on-shell Z bosons and are a precursor to the physical H →Z f f ¯ calculation. We present compact numerical formulas for our results and demonstrate that the logarithmic contributions that result from the renormalization group evolution of the SMEFT coefficients are larger than the finite next-to-leading-order contributions to the decay widths. As a byproduct of our calculation, we obtain the first complete result for the finite corrections to Gμ in the SMEFT.

Impact of Host Age and Parity on Susceptibility to Severe Urinary Tract Infection in a Murine Model

PubMed Central

Kline, Kimberly A.; Schwartz, Drew J.; Gilbert, Nicole M.; Lewis, Amanda L.

2014-01-01

The epidemiology and bacteriology of urinary tract infection (UTI) varies across the human lifespan, but the reasons for these differences are poorly understood. Using established monomicrobial and polymicrobial murine UTI models caused by uropathogenic Escherichia coli (UPEC) and/or Group B Streptococcus (GBS), we demonstrate age and parity as inter-related factors contributing to UTI susceptibility. Young nulliparous animals exhibited 10–100-fold higher bacterial titers compared to older animals. In contrast, multiparity was associated with more severe acute cystitis in older animals compared to age-matched nulliparous controls, particularly in the context of polymicrobial infection where UPEC titers were ∼1000-fold higher in the multiparous compared to the nulliparous host. Multiparity was also associated with significantly increased risk of chronic high titer UPEC cystitis and ascending pyelonephritis. Further evidence is provided that the increased UPEC load in multiparous animals required TLR4-signaling. Together, these data strongly suggest that the experience of childbearing fundamentally and permanently changes the urinary tract and its response to pathogens in a manner that increases susceptibility to severe UTI. Moreover, this murine model provides a system for dissecting these and other lifespan-associated risk factors contributing to severe UTI in at-risk groups. PMID:24835885

Impact of host age and parity on susceptibility to severe urinary tract infection in a murine model.

PubMed

Kline, Kimberly A; Schwartz, Drew J; Gilbert, Nicole M; Lewis, Amanda L

2014-01-01

The epidemiology and bacteriology of urinary tract infection (UTI) varies across the human lifespan, but the reasons for these differences are poorly understood. Using established monomicrobial and polymicrobial murine UTI models caused by uropathogenic Escherichia coli (UPEC) and/or Group B Streptococcus (GBS), we demonstrate age and parity as inter-related factors contributing to UTI susceptibility. Young nulliparous animals exhibited 10-100-fold higher bacterial titers compared to older animals. In contrast, multiparity was associated with more severe acute cystitis in older animals compared to age-matched nulliparous controls, particularly in the context of polymicrobial infection where UPEC titers were ∼1000-fold higher in the multiparous compared to the nulliparous host. Multiparity was also associated with significantly increased risk of chronic high titer UPEC cystitis and ascending pyelonephritis. Further evidence is provided that the increased UPEC load in multiparous animals required TLR4-signaling. Together, these data strongly suggest that the experience of childbearing fundamentally and permanently changes the urinary tract and its response to pathogens in a manner that increases susceptibility to severe UTI. Moreover, this murine model provides a system for dissecting these and other lifespan-associated risk factors contributing to severe UTI in at-risk groups.

In silico modelling of thiazolidine derivatives with antioxidant potency: Models quantify the degree of contribution of molecular fragments towards the free radical scavenging ability

NASA Astrophysics Data System (ADS)

De, Biplab; Adhikari, Indrani; Nandy, Ashis; Saha, Achintya; Goswami, Binoy Behari

2017-06-01

Design and development of antioxidant supplements constitute an essential aspect of research in order to derive molecules that would help to combat the free radical invasion to the human body and curb oxidative stress related diseases. The present work deals with the development of in silico models for a series of thiazolidine derivatives having antioxidant potential. The objective of the work is to obtain models that would help to design new thazolidine derivatives based on substituent modification and thereby predict their activity profile. The QSAR model thus developed helps in quantification of the extent of contribution of the various molecular fragments towards the activity of the molecules, while the 3D pharmacophore model provides a brief idea of the essential molecular features that help the molecules to interact with the neighbouring free radicals. Both the models have been extensively validated which ensures their predictive ability as well the potential to search molecular databases for selection of thiazolidine derivatives with potent antioxidant activity. The models can thus be utilised effectively for database searching with the aim to isolate active antioxidants belonging to the thiazolidine group.

COLLABORATIVE RESEARCH: Study of Aerosol Sources and Processing at the GVAX Pantnagar Supersite

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

Thornton, Joel A.; Worsnop, Douglas

2016-09-22

This project was part of a collaborative campaign, including the participation of scientists from seven research groups as part of the Winter Intensive Operating Period (January-February 2012) of the Clean Air for London (ClearfLo) campaign at a rural site in Detling, UK, 45 km southeast of central London to study wintertime sources of urban particulate matter. The UW contribution by PI Thornton’s group was to make the first deployment of a chemical ionization mass spectrometer instrument (MOVI-CI-ToFMS) to measure both particle and gas phase organic acids. The new instrument ran nearly continuously during the ClearfLo WINTER IOP at the Detlingmore » site, producing a first-ever data set of molecular composition information that can be used for source apportionment and process studies. The UW group published a paper in Environmental Science and Technology and contributed to another (Bohnenstengel et al BAMS 2015) detailing a direct molecular connection between biomass/biofuel burning particles and aerosol light absorption. The ES&T paper (Mohr, et al ES&T 2013) has received 42 citations in just 3 years indicative of its significant impact on the field. These measurements of urban and rural aerosol properties will contribute to improved modeling of regional aerosol emissions, and of atmospheric aging and removal.« less

The role of the built environment in explaining educational inequalities in walking and cycling among adults in the Netherlands.

PubMed

van Wijk, Daniël C; Groeniger, Joost Oude; van Lenthe, Frank J; Kamphuis, Carlijn B M

2017-03-31

This study examined whether characteristics of the residential built environment (i.e. population density, level of mixed land use, connectivity, accessibility of facilities, accessibility of green) contributed to educational inequalities in walking and cycling among adults. Data from participants (32-82 years) of the 2011 survey of the Dutch population-based GLOBE study were used (N = 2375). Highest attained educational level (independent variable) and walking for transport, cycling for transport, walking in leisure time and cycling in leisure time (dependent variables) were self-reported in the survey. GIS-systems were used to obtain spatial data on residential built environment characteristics. A four-step mediation-based analysis with log-linear regression models was used to examine to contribution of the residential built environment to educational inequalities in walking and cycling. As compared to the lowest educational group, the highest educational group was more likely to cycle for transport (RR 1.13, 95% CI 1.04-1.23), walk in leisure time (RR 1.12, 95% CI 1.04-1.21), and cycle in leisure time (RR 1.12, 95% CI 1.03-1.22). Objective built environment characteristics were related to these outcomes, but contributed minimally to educational inequalities in walking and cycling. On the other hand, compared to the lowest educational group, the highest educational group was less likely to walk for transport (RR 0.91, 95% CI 0.82-1.01), which could partly be attributed to differences in the built environment. This study found that objective built environment characteristics contributed minimally to educational inequalities in walking and cycling in the Netherlands.

Designing and Evaluating Interventions to Eliminate Racial and Ethnic Disparities in Health Care

PubMed Central

Cooper, Lisa A; Hill, Martha N; Powe, Neil R

2002-01-01

A large number of factors contribute to racial and ethnic disparities in health status. Health care professionals, researchers, and policymakers have believed for some time that access to care is the centerpiece in the elimination of these health disparities. The Institute of Medicine's (IOM) model of access to health services includes personal, financial, and structural barriers, health service utilization, and mediators of care. This model can be used to describe the interactions among these factors and their impact on health outcomes and equity of services among racial and ethnic groups. We present a modified version of the IOM model that incorporates the features of other access models and highlights barriers and mediators that are relevant for interventions designed to eliminate disparities in U.S. health care. We also suggest that interventions to eliminate disparities and achieve equity in health care services be considered within the broader context of improving quality of care. Some health service intervention studies have shown improvements in the health of disadvantaged groups. If properly designed and implemented, these interventions could be used to reduce health disparities. Successful features of interventions include the use of multifaceted, intense approaches, culturally and linguistically appropriate methods, improved access to care, tailoring, the establishment of partnerships with stakeholders, and community involvement. However, in order to be effective in reducing disparities in health care and health status, important limitations of previous studies need to be addressed, including the lack of control groups, nonrandom assignment of subjects to experimental interventions, and use of health outcome measures that are not validated. Interventions might be improved by targeting high-risk populations, focusing on the most important contributing factors, including measures of appropriateness and quality of care and health outcomes, and prioritizing dissemination efforts. PMID:12133164

Characteristics and contributions of hyperandrogenism to insulin resistance and other metabolic profiles in polycystic ovary syndrome.

PubMed

Huang, Rong; Zheng, Jun; Li, Shengxian; Tao, Tao; Ma, Jing; Liu, Wei

2015-05-01

To investigate the different characteristics in Chinese Han women with polycystic ovary syndrome, and to analyze the significance of hyperandrogenism in insulin resistance and other metabolic profiles. A cross-sectional study. Medical university hospital. A total of 229 women with polycystic ovary syndrome aged 18-45 years. Women with polycystic ovary syndrome, diagnosed by Rotterdam criteria, were divided into four groups according to the quartile intervals of free androgen index levels. Comparisons between groups were performed using one-way analysis of variance. Stepwise logistic regression analysis was performed to investigate the association between homeostasis model assessment-insulin resistance and independent variables. Within the four phenotypes, women with phenotype 1 (hyperandrogenism, oligo/anovulation, and polycystic ovaries) exhibited higher total testosterone, free androgen index, androstenedione, low-density lipoprotein, and lower quantitative insulin sensitivity check index (p < 0.05); women with phenotype 4 (oligo/anovulation and polycystic ovaries) showed lower total cholesterol, low-density lipoprotein, and homeostasis model assessment-insulin resistance, but higher high-density lipoprotein (p < 0.05). The levels of triglycerides, total cholesterol, low-density lipoprotein, and homeostasis model assessment-insulin resistance significantly increased, but high-density lipoprotein and quantitative insulin sensitivity check index decreased with the elevation of free androgen index intervals. After adjustment for lipid profiles, free androgen index was significantly associated with homeostasis model assessment-insulin resistance in both lean and overweight/obese women (odds ratio 1.302, p = 0.039 in lean vs. odds ratio 1.132, p = 0.036 in overweight/obese). Phenotypes 1 and 4 represent groups with the most and least severe metabolic profiles, respectively. Hyperandrogenism, particularly with elevated free androgen index, is likely a key contributing factor for insulin resistance and for the aggravation of other metabolic profiles. © 2015 Nordic Federation of Societies of Obstetrics and Gynecology.

Oxytocin promotes intuitive rather than deliberated cooperation with the in-group.

PubMed

Ten Velden, Femke S; Daughters, Katie; De Dreu, Carsten K W

2017-06-01

A contribution to a special issue on Hormones and Human Competition. In intergroup settings, individuals prefer cooperating with their in-group, and sometimes derogate and punish out-groups. Here we replicate earlier work showing that such in-group bounded cooperation is conditioned by oxytocin and extend it by showing that oxytocin-motivated in-group cooperation is intuitive rather than deliberated. Healthy males (N=65) and females (N=129) self-administered intranasal placebo or 24IU oxytocin in a double-blind placebo-controlled between-subjects design, were assigned to a three-person in-group (that faced a 3-person out-group), and given an endowment from which they could contribute to a within-group pool (benefitting the in-group), and/or to a between-group pool (benefitting the in-group and punishing the out-group). Prior to decision-making, participants performed a Stroop Interference task that was either cognitively taxing, or not. Cognitively taxed individuals kept less to themselves and contributed more to the within-group pool. Furthermore, participants receiving placebo contributed more to the within-group pool when they were cognitively taxed rather than not; those receiving oxytocin contributed to the within-group pool regardless of cognitive taxation. Neither taxation nor treatment influenced contributions to the between-group pool, and no significant sex differences were observed. It follows that in intergroup settings (i) oxytocin increases in-group bounded cooperation, (ii) oxytocin neither reduces nor increases out-group directed spite, and (iii) oxytocin-induced in-group cooperation is independent of cognitive taxation and, therefore, likely to be intuitive rather than consciously deliberated. Copyright © 2016 Elsevier Inc. All rights reserved.

New Physics Beyond the Standard Model

NASA Astrophysics Data System (ADS)

Cai, Haiying

In this thesis we discuss several extensons of the standard model, with an emphasis on the hierarchy problem. The hierachy problem related to the Higgs boson mass is a strong indication of new physics beyond the Standard Model. In the literature, several mechanisms, e.g. , supersymmetry (SUSY), the little Higgs and extra dimensions, are proposed to explain why the Higgs mass can be stabilized to the electroweak scale. In the Standard Model, the largest quadratically divergent contribution to the Higgs mass-squared comes from the top quark loop. We consider a few novel possibilities on how this contribution is cancelled. In the standard SUSY scenario, the quadratic divergence from the fermion loops is cancelled by the scalar superpartners and the SUSY breaking scale determines the masses of the scalars. We propose a new SUSY model, where the superpartner of the top quark is spin-1 rather than spin-0. In little Higgs theories, the Higgs field is realized as a psudo goldstone boson in a nonlinear sigma model. The smallness of its mass is protected by the global symmetry. As a variation, we put the little Higgs into an extra dimensional model where the quadratically divergent top loop contribution to the Higgs mass is cancelled by an uncolored heavy "top quirk" charged under a different SU(3) gauge group. Finally, we consider a supersymmetric warped extra dimensional model where the superpartners have continuum mass spectra. We use the holographic boundary action to study how a mass gap can arise to separate the zero modes from continuum modes. Such extensions of the Standard Model have novel signatures at the Large Hadron Collider.

Formative research and stakeholder participation in intervention development.

PubMed

Vastine, Amy; Gittelsohn, Joel; Ethelbah, Becky; Anliker, Jean; Caballero, Benjamin

2005-01-01

To present a model for using formative research and stakeholder participation to develop a community-based dietary intervention targeting American Indians. Formative research included interviews, assessment of food- purchasing frequency and preparation methods, and dietary recalls. Stakeholders contributed to intervention development through formative research, a program planning workshop, group feedback, and implementation training. Foods high in fat and sugar are commonly consumed. Barriers to healthy eating include low availability, perceived high cost, and poor flavor. Stakeholder participation contributed to the development of a culturally appropriate intervention. This approach resulted in project acceptance, stakeholder collaboration, and a culturally appropriate program.

A qualitative descriptive study of the group prenatal care experience: perceptions of women with low-risk pregnancies and their midwives.

PubMed

McDonald, Sarah D; Sword, Wendy; Eryuzlu, Leyla E; Biringer, Anne B

2014-09-26

Group prenatal care (GPC) originated in 1994 as an innovative model of prenatal care delivery. In GPC, eight to twelve pregnant women of similar gestational age meet with a health care provider to receive their prenatal check-up and education in a group setting. GPC offers significant health benefits in comparison to traditional, one-on-one prenatal care. Women in GPC actively engage in their healthcare and experience a supportive network with one another. The purpose of this study was to better understand the GPC experience of women and care providers in a lower risk group of women than often has been previously studied. This qualitative descriptive study collected data through three focus group interviews--two with women who had completed GPC at a midwifery clinic in Ontario, Canada and one with the midwives at the clinic. Data was analyzed through open coding to identify themes. Nine women and five midwives participated in the focus groups, from which eight categories as well as further subcategories were identified: The women and midwives noted reasons for participating (connections, education, efficiency). Participants suggested both benefits (learning from the group, normalizing the pregnancy experience, preparedness for labour and delivery, and improved relationships as all contributing to positive health outcomes) and concerns with GPC (e.g. sufficient time with the midwife) which generally diminished with experience. Suggestions for change focused on content, environment, partners, and access to the midwives. Challenges to providing GPC included scheduling and systems-level issues such as funding and regulation. Flexibility and commitment to the model facilitated it. Comparison with other models of care identified less of a relationship with the midwife, but more information received. In promoting GPC, women would emphasize the philosophy of care to other women and the midwives would promote the reduction in workload and women's independence to colleagues. Overall, women and midwives expressed a high level of satisfaction with their GPC experience. This study gained insight into previously unexplored areas of the GPC experience, perceptions of processes that contribute to positive health outcomes, strategies to promote GPC and elements that enhance the feasibility of GPC.

Two Model-Based Methods for Policy Analyses of Fine Particulate Matter Control in China: Source Apportionment and Source Sensitivity

NASA Astrophysics Data System (ADS)

Li, X.; Zhang, Y.; Zheng, B.; Zhang, Q.; He, K.

2013-12-01

Anthropogenic emissions have been controlled in recent years in China to mitigate fine particulate matter (PM2.5) pollution. Recent studies show that sulfate dioxide (SO2)-only control cannot reduce total PM2.5 levels efficiently. Other species such as nitrogen oxide, ammonia, black carbon, and organic carbon may be equally important during particular seasons. Furthermore, each species is emitted from several anthropogenic sectors (e.g., industry, power plant, transportation, residential and agriculture). On the other hand, contribution of one emission sector to PM2.5 represents contributions of all species in this sector. In this work, two model-based methods are used to identify the most influential emission sectors and areas to PM2.5. The first method is the source apportionment (SA) based on the Particulate Source Apportionment Technology (PSAT) available in the Comprehensive Air Quality Model with extensions (CAMx) driven by meteorological predictions of the Weather Research and Forecast (WRF) model. The second method is the source sensitivity (SS) based on an adjoint integration technique (AIT) available in the GEOS-Chem model. The SA method attributes simulated PM2.5 concentrations to each emission group, while the SS method calculates their sensitivity to each emission group, accounting for the non-linear relationship between PM2.5 and its precursors. Despite their differences, the complementary nature of the two methods enables a complete analysis of source-receptor relationships to support emission control policies. Our objectives are to quantify the contributions of each emission group/area to PM2.5 in the receptor areas and to intercompare results from the two methods to gain a comprehensive understanding of the role of emission sources in PM2.5 formation. The results will be compared in terms of the magnitudes and rankings of SS or SA of emitted species and emission groups/areas. GEOS-Chem with AIT is applied over East Asia at a horizontal grid resolution of 0.5° (Lat) × 0.67° (Lon). WRF/CAMx with PSAT is applied to nested grids: 36-km × 36-km over China and 12-km × 12-km over northern China. These simulations are performed for 2006 and 2011. Beijing and northern Hebei are selected as representative receptor areas. Simulated surface concentrations by both models are evaluated with available observations in China. Focusing on inorganic aerosols (sulfate, nitrate and ammonium), preliminary SS results from GEOS-Chem/AIT at Beijing identify the top three major emission sectors to be agriculture, residential, and transportation in winter and agriculture, industry and power plant in summer. The top four source areas are northern Hebei, local, Neimenggu, and Liaoning in winter and northern Hebei, local, Shandong, and southern Hebei in summer. The synthesis of SS and SA for influential emission groups or areas from this work will provide a quantitative basis for emission control strategy development and policy making for PM2.5 control in China.

Assessing Peer Leader Skill Acquisition and Group Dynamics in a First-Year Calculus Course

ERIC Educational Resources Information Center

Glover, Rebecca; Hammond, Nicholas B.; Smith, Justin; Guerra, Dalyana

2018-01-01

Peer-led team learning (PLTL), specifically the model known as 'Workshops', has been shown to contribute positively and significantly to student success in STEM courses across subjects (Gosser et al., 2001). Our research adds to the SOTL literature describing the effectiveness of Workshops by reporting on the changes in student leaders. We examine…

The Effects of a Participatory Action Research Intervention on Middle School Students' Understanding of Schools, Culture and Place

ERIC Educational Resources Information Center

Cassie, Jonathan Martin

2011-01-01

School violence is a complex cultural problem that affects most schools. This study used a participatory action research model involving mapmaking, photography and intercultural grouping to understand how one school's physical environment and social geography contributed to interethnic tensions on campus. The study found that mapmaking allowed…

An International Perspective: Constructing Intervention Strategies for Families in Mexico

ERIC Educational Resources Information Center

Natera Rey, Guillermina; Mora-Rios, Jazmin; Tiburcio Sainz, Marcela; Medina Aguilar, Perla

2010-01-01

In this article, the authors comment on the contribution of the Alcohol, Drugs and the Family research group to draw public and scientific attention to the suffering and needs of families coping with addiction problems. The article also describes the impact of the stress-strain-coping-support model and the 5-Step Method on the research,…

NATIONAL URBAN DATABASE AND ACCESS PORTAL TOOL (NUDAPT): FACILITATING ADVANCEMENTS IN URBAN METEOROLOGY AND CLIMATE MODELING WITH COMMUNITY-BASED URBAN DATABASES

EPA Science Inventory

We discuss the initial design and application of the National Urban Database and Access Portal Tool (NUDAPT). This new project is sponsored by the USEPA and involves collaborations and contributions from many groups from federal and state agencies, and from private and academic i...

Cooperative Trust Games

DTIC Science & Technology

2013-01-01

the more widely recognized competitive (non-cooperative) game theory. Cooperative game theory focuses on what groups of self-interested agents can...provides immediate justification for using non-cooperative game theory as the basis for modeling the purely competitive agents. 2.4. Superadditive...the competitive and altruistic contributions of the subset team. Definition: Given a payoff function ( ) in a subset team game , the total marginal

Modeling the effects of harvest alternatives on mitigating oak decline in a Central Hardwood Forest landscape

Treesearch

Wen J. Wang; Hong S. He; Martin A. Spetich; Stephen R. Shifley; Frank R. III Thompson; Jacob S. Fraser

2013-01-01

Oak decline is a process induced by complex interactions of predisposing factors, inciting factors, and contributing factors operating at tree, stand, and landscape scales. It has greatly altered species composition and stand structure in affected areas. Thinning, clearcutting, and group selection are widely adopted harvest alternatives for reducing forest...

Plausible role for CHW peer support groups in increasing care-seeking in an integrated community case management project in Rwanda: a mixed methods evaluation.

PubMed

Langston, Anne; Weiss, Jennifer; Landegger, Justine; Pullum, Thomas; Morrow, Melanie; Kabadege, Melene; Mugeni, Catherine; Sarriot, Eric

2014-08-01

The Kabeho Mwana project (2006-2011) supported the Rwanda Ministry of Health (MOH) in scaling up integrated community case management (iCCM) of childhood illness in 6 of Rwanda's 30 districts. The project trained and equipped community health workers (CHWs) according to national guidelines. In project districts, Kabeho Mwana staff also trained CHWs to conduct household-level health promotion and established supervision and reporting mechanisms through CHW peer support groups (PSGs) and quality improvement systems. The 2005 and 2010 Demographic and Health Surveys were re-analyzed to evaluate how project and non-project districts differed in terms of care-seeking for fever, diarrhea, and acute respiratory infection symptoms and related indicators. We developed a logit regression model, controlling for the timing of the first CHW training, with the district included as a fixed categorical effect. We also analyzed qualitative data from the final evaluation to examine factors that may have contributed to improved outcomes. While there was notable improvement in care-seeking across all districts, care-seeking from any provider for each of the 3 conditions, and for all 3 combined, increased significantly more in the project districts. CHWs contributed a larger percentage of consultations in project districts (27%) than in non-project districts (12%). Qualitative data suggested that the PSG model was a valuable sub-level of CHW organization associated with improved CHW performance, supervision, and social capital. The iCCM model implemented by Kabeho Mwana resulted in greater improvements in care-seeking than those seen in the rest of the country. Intensive monitoring, collaborative supervision, community mobilization, and CHW PSGs contributed to this success. The PSGs were a unique contribution of the project, playing a critical role in improving care-seeking in project districts. Effective implementation of iCCM should therefore include CHW management and social support mechanisms. Finally, re-analysis of national survey data improved evaluation findings by providing impact estimates.

The role of social and ecological processes in structuring animal populations: a case study from automated tracking of wild birds

PubMed Central

Farine, Damien R.; Firth, Josh A.; Aplin, Lucy M.; Crates, Ross A.; Culina, Antica; Garroway, Colin J.; Hinde, Camilla A.; Kidd, Lindall R.; Milligan, Nicole D.; Psorakis, Ioannis; Radersma, Reinder; Verhelst, Brecht; Voelkl, Bernhard; Sheldon, Ben C.

2015-01-01

Both social and ecological factors influence population process and structure, with resultant consequences for phenotypic selection on individuals. Understanding the scale and relative contribution of these two factors is thus a central aim in evolutionary ecology. In this study, we develop a framework using null models to identify the social and spatial patterns that contribute to phenotypic structure in a wild population of songbirds. We used automated technologies to track 1053 individuals that formed 73 737 groups from which we inferred a social network. Our framework identified that both social and spatial drivers contributed to assortment in the network. In particular, groups had a more even sex ratio than expected and exhibited a consistent age structure that suggested local association preferences, such as preferential attachment or avoidance. By contrast, recent immigrants were spatially partitioned from locally born individuals, suggesting differential dispersal strategies by phenotype. Our results highlight how different scales of social decision-making, ranging from post-natal dispersal settlement to fission–fusion dynamics, can interact to drive phenotypic structure in animal populations. PMID:26064644

Mothers' groups enrich diet and culture through promoting traditional Quichua foods.

PubMed

Roche, Marion L; Ambato, Lorena; Sarsoza, Julieta; Kuhnlein, Harriet V

2017-11-01

Indigenous Peoples in Latin America bear a disproportionate burden of undernutrition, yet traditional foods, including wild leafy greens, can contribute nutritional value to diets. As part of a community nutrition intervention using local foods in highland Tungurahua, Ecuador, mothers' groups promoted the consumption of wild leafy greens through community cooking clubs and recipe competitions at local fairs. The objective was to assess the social, cultural, and nutritional potential of a mothers' club intervention that promoted 2 indigenous greens (stinging nettle/Urtica dioica L. and round-leaved dock/Rumex obtusifolius L.) into children's diets. Key informant interviews and focus groups were conducted with 54 mothers and 16 elders to identify perceptions of the intervention and traditional foods. Social and cultural dimensions were identified through content analysis. The nutritional contribution of the leafy greens was estimated through semiquantitative food frequency questionnaires conducted with 160 participant mothers and 98 mothers living in comparison communities who had not been exposed to the intervention. The use of local foods generated pride for mothers and elders. Nonfood uses of the nettle proved an initial barrier to acceptance; however, peer support within mothers' groups enabled increased consumption. The greens were estimated to contribute an additional 8% vitamin A, 7% iron, 12% vitamin C, and 27% folate to children's recommended dietary intakes. By promoting wild leafy greens, mothers' groups improved food security and the cultural and nutritional value of their diets. Additionally, mothers' cooking clubs increased self-efficacy and cultural identity for Quichua women, offering a highly acceptable nutrition intervention model. © 2018 John Wiley & Sons Ltd.

Seasonal and Inter-Annual Changes in the Distribution of Dominant Phytoplancton Groups in the Global Ocean

NASA Astrophysics Data System (ADS)

Severine, A.; Cyril, M.; Yves, D.; Laurent, B.; Hubert, L.

2006-12-01

The fate of fixed organic carbon in the ocean strongly varies with the phytoplankton group that makes photosynthesis. The monitoring of phytoplankton groups in the global ocean is thus of primary importance to evaluate and improve ocean carbon models. A new method (PHYSAT; Alvain et al., 2005) enables to distinguish between four different groups from space using SeaWiFS ocean color measurements. In addition to these four initial phytoplankton groups, which are diatoms, Prochlorococcus, Synecochoccus and haptophytes, we show that PHYSAT is also capable of identifying blooms of phaeocystis and coccolithophorids. Daily global SeaWiFS level-3 data from September 1997 to December 2004 were processed using PHYSAT. We present here the first monthly mean global climatology of the dominant phytoplankton groups. The seasonal cycle is discussed, with particular emphasis on the succession of phytoplankton groups during the North Atlantic spring bloom and on the coexistence of large phaeocystis and diatoms blooms during winter in the Austral Ocean. We also present the inter-annual variability for the 1998-2004 period. The contribution of diatoms to the total chlorophyll is highly variable (up to a factor of two) from one year to the other in both Atlantic and Austral Oceans, suggesting a significant variability in organic carbon export by diatoms in these regions. On the opposite, the phaeocystis contribution is less variable in the Austral Ocean.

The anti-human trafficking collaboration model and serving victims: Providers' perspectives on the impact and experience.

PubMed

Kim, Hea-Won; Park, Taekyung; Quiring, Stephanie; Barrett, Diana

2018-01-01

A coalition model is often used to serve victims of human trafficking but little is known about whether the model is adequately meeting the needs of the victims. The purpose of this study was to examine anti-human trafficking collaboration model in terms of its impact and the collaborative experience, including challenges and lessons learned from the service providers' perspective. Mixed methods study was conducted to evaluate the impact of a citywide anti-trafficking coalition model from the providers' perspectives. Web-based survey was administered with service providers (n = 32) and focus groups were conducted with Core Group members (n = 10). Providers reported the coalition model has made important impacts in the community by increasing coordination among the key agencies, law enforcement, and service providers and improving quality of service provision. Providers identified the improved and expanded partnerships among coalition members as the key contributing factor to the success of the coalition model. Several key strategies were suggested to improve the coalition model: improved referral tracking, key partner and protocol development, and information sharing.

Modeling the gas-phase thermochemistry of organosulfur compounds.

PubMed

Vandeputte, Aäron G; Sabbe, Maarten K; Reyniers, Marie-Françoise; Marin, Guy B

2011-06-27

Key to understanding the involvement of organosulfur compounds in a variety of radical chemistries, such as atmospheric chemistry, polymerization, pyrolysis, and so forth, is knowledge of their thermochemical properties. For organosulfur compounds and radicals, thermochemical data are, however, much less well documented than for hydrocarbons. The traditional recourse to the Benson group additivity method offers no solace since only a very limited number of group additivity values (GAVs) is available. In this work, CBS-QB3 calculations augmented with 1D hindered rotor corrections for 122 organosulfur compounds and 45 organosulfur radicals were used to derive 93 Benson group additivity values, 18 ring-strain corrections, 2 non-nearest-neighbor interactions, and 3 resonance corrections for standard enthalpies of formation, standard molar entropies, and heat capacities for organosulfur compounds and organosulfur radicals. The reported GAVs are consistent with previously reported GAVs for hydrocarbons and hydrocarbon radicals and include 77 contributions, among which 26 radical contributions, which, to the best of our knowledge, have not been reported before. The GAVs allow one to estimate the standard enthalpies of formation at 298 K, the standard entropies at 298 K, and standard heat capacities in the temperature range 300-1500 K for a large set of organosulfur compounds, that is, thiols, thioketons, polysulfides, alkylsulfides, thials, dithioates, and cyclic sulfur compounds. For a validation set of 26 organosulfur compounds, the mean absolute deviation between experimental and group additively modeled enthalpies of formation amounts to 1.9  kJ  mol(-1). For an additional set of 14 organosulfur compounds, it was shown that the mean absolute deviations between calculated and group additively modeled standard entropies and heat capacities are restricted to 4 and 2 J  mol(-1)  K(-1), respectively. As an alternative to Benson GAVs, 26 new hydrogen-bond increments are reported, which can also be useful for the prediction of radical thermochemistry. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

An application of seasonal ARIMA models on group commodities to forecast Philippine merchandise exports performance

NASA Astrophysics Data System (ADS)

Natividad, Gina May R.; Cawiding, Olive R.; Addawe, Rizavel C.

2017-11-01

The increase in the merchandise exports of the country offers information about the Philippines' trading role within the global economy. Merchandise exports statistics are used to monitor the country's overall production that is consumed overseas. This paper investigates the comparison between two models obtained by a) clustering the commodity groups into two based on its proportional contribution to the total exports, and b) treating only the total exports. Different seasonal autoregressive integrated moving average (SARIMA) models were then developed for the clustered commodities and for the total exports based on the monthly merchandise exports of the Philippines from 2011 to 2016. The data set used in this study was retrieved from the Philippine Statistics Authority (PSA) which is the central statistical authority in the country responsible for primary data collection. A test for significance of the difference between means at 0.05 level of significance was then performed on the forecasts produced. The result indicates that there is a significant difference between the mean of the forecasts of the two models. Moreover, upon a comparison of the root mean square error (RMSE) and mean absolute error (MAE) of the models, it was found that the models used for the clustered groups outperform the model for the total exports.

Thermally Stimulated Currents in Nanocrystalline Titania

PubMed Central

Bruzzi, Mara; Mori, Riccardo; Baldi, Andrea; Cavallaro, Alessandro; Scaringella, Monica

2018-01-01

A thorough study on the distribution of defect-related active energy levels has been performed on nanocrystalline TiO2. Films have been deposited on thick-alumina printed circuit boards equipped with electrical contacts, heater and temperature sensors, to carry out a detailed thermally stimulated currents analysis on a wide temperature range (5–630 K), in view to evidence contributions from shallow to deep energy levels within the gap. Data have been processed by numerically modelling electrical transport. The model considers both free and hopping contribution to conduction, a density of states characterized by an exponential tail of localized states below the conduction band and the convolution of standard Thermally Stimulated Currents (TSC) emissions with gaussian distributions to take into account the variability in energy due to local perturbations in the highly disordered network. Results show that in the low temperature range, up to 200 K, hopping within the exponential band tail represents the main contribution to electrical conduction. Above room temperature, electrical conduction is dominated by free carriers contribution and by emissions from deep energy levels, with a defect density ranging within 1014–1018 cm−3, associated with physio- and chemi-sorbed water vapour, OH groups and to oxygen vacancies. PMID:29303976

Thermally Stimulated Currents in Nanocrystalline Titania.

PubMed

Bruzzi, Mara; Mori, Riccardo; Baldi, Andrea; Carnevale, Ennio Antonio; Cavallaro, Alessandro; Scaringella, Monica

2018-01-05

A thorough study on the distribution of defect-related active energy levels has been performed on nanocrystalline TiO₂. Films have been deposited on thick-alumina printed circuit boards equipped with electrical contacts, heater and temperature sensors, to carry out a detailed thermally stimulated currents analysis on a wide temperature range (5-630 K), in view to evidence contributions from shallow to deep energy levels within the gap. Data have been processed by numerically modelling electrical transport. The model considers both free and hopping contribution to conduction, a density of states characterized by an exponential tail of localized states below the conduction band and the convolution of standard Thermally Stimulated Currents (TSC) emissions with gaussian distributions to take into account the variability in energy due to local perturbations in the highly disordered network. Results show that in the low temperature range, up to 200 K, hopping within the exponential band tail represents the main contribution to electrical conduction. Above room temperature, electrical conduction is dominated by free carriers contribution and by emissions from deep energy levels, with a defect density ranging within 10 14 -10 18 cm -3 , associated with physio- and chemi-sorbed water vapour, OH groups and to oxygen vacancies.

NASA's Heliophysics Theory Program - Accomplishments in Life Cycle Ending 2011

NASA Technical Reports Server (NTRS)

Grebowsky, J.

2011-01-01

NASA's Heliophysics Theory Program (HTP) is now into a new triennial cycle of funded research, with new research awards beginning in 2011. The theory program was established by the (former) Solar Terrestrial Division in 1980 to redress a weakness of support in the theory area. It has been a successful, evolving scientific program with long-term funding of relatively large "critical mass groups" pursuing theory and modeling on a scale larger than that available within the limits of traditional NASA Supporting Research and Technology (SR&T) awards. The results of the last 3 year funding cycle, just ended, contributed to ever more cutting edge theoretical understanding of all parts of the Sun-Earth Connection chain. Advances ranged from the core of the Sun out into the corona, through the solar wind into the Earth's magnetosphere and down to the ionosphere and lower atmosphere, also contributing to understanding the environments of other solar system bodies. The HTP contributions were not isolated findings but continued to contribute to the planning and implementation of NASA spacecraft missions and to the development of the predictive computer models that have become the workhorses for analyzing satellite and ground-based measurements.

Comparison of rigorous and simple vibrational models for the CO2 gasdynamic laser

NASA Technical Reports Server (NTRS)

Monson, D. J.

1977-01-01

The accuracy of a simple vibrational model for computing the gain in a CO2 gasdynamic laser is assessed by comparing results computed from it with results computed from a rigorous vibrational model. The simple model is that of Anderson et al. (1971), in which the vibrational kinetics are modeled by grouping the nonequilibrium vibrational degrees of freedom into two modes, to each of which there corresponds an equation describing vibrational relaxation. The two models agree fairly well in the computed gain at low temperatures, but the simple model predicts too high a gain at the higher temperatures of current interest. The sources of error contributing to the overestimation given by the simple model are determined by examining the simplified relaxation equations.

Decision-case mix model for analyzing variation in cesarean rates.

PubMed

Eldenburg, L; Waller, W S

2001-01-01

This article contributes a decision-case mix model for analyzing variation in c-section rates. Like recent contributions to the literature, the model systematically takes into account the effect of case mix. Going beyond past research, the model highlights differences in physician decision making in response to obstetric factors. Distinguishing the effects of physician decision making and case mix is important in understanding why c-section rates vary and in developing programs to effect change in physician behavior. The model was applied to a sample of deliveries at a hospital where physicians exhibited considerable variation in their c-section rates. Comparing groups with a low versus high rate, the authors' general conclusion is that the difference in physician decision tendencies (to perform a c-section), in response to specific obstetric factors, is at least as important as case mix in explaining variation in c-section rates. The exact effects of decision making versus case mix depend on how the model application defines the obstetric condition of interest and on the weighting of deliveries by their estimated "risk of Cesarean." The general conclusion is supported by an additional analysis that uses the model's elements to predict individual physicians' annual c-section rates.

Who would you like to be like? Family, village, and national role models among Black youth in rural South Africa

PubMed Central

Madhavan, Sangeetha; Crowell, Jacqueline

2015-01-01

In this paper, we examine how Black youth in rural South Africa construct role models and connect them to their own life aspirations. We pay particular attention to individual and group identity development in shaping these perceptions. Based on analysis of qualitative data from 99 Black male and female youth aged 14–22, we find that 1) the choice of role models reflects a balancing strategy to reconcile individual and group identity development; 2) while the reasons they give for choosing role models are aligned with dominant models of upward mobility in the new South Africa (and globally), our respondents are also attuned to the difficulty of attaining such success and 3) the choices underscore the continued importance of close and extended kin amidst an increasingly ego focused life strategy aimed at individual status attainment. These findings can contribute to strengthening the effectiveness of intervention programs aimed at strengthening positive influences in the lives of Black youth in South Africa. PMID:26005284

QSAR modeling of acute toxicity on mammals caused by aromatic compounds: the case study using oral LD50 for rats.

PubMed

Rasulev, Bakhtiyor; Kusić, Hrvoje; Leszczynska, Danuta; Leszczynski, Jerzy; Koprivanac, Natalija

2010-05-01

The goal of the study was to predict toxicity in vivo caused by aromatic compounds structured with a single benzene ring and the presence or absence of different substituent groups such as hydroxyl-, nitro-, amino-, methyl-, methoxy-, etc., by using QSAR/QSPR tools. A Genetic Algorithm and multiple regression analysis were applied to select the descriptors and to generate the correlation models. The most predictive model is shown to be the 3-variable model which also has a good ratio of the number of descriptors and their predictive ability to avoid overfitting. The main contributions to the toxicity were shown to be the polarizability weighted MATS2p and the number of certain groups C-026 descriptors. The GA-MLRA approach showed good results in this study, which allows the building of a simple, interpretable and transparent model that can be used for future studies of predicting toxicity of organic compounds to mammals.

Effects of safety behaviour on the maintenance of anxiety and negative belief social anxiety disorder.

PubMed

Okajima, Isa; Kanai, Yoshihiro; Chen, Junwen; Sakano, Yuji

2009-01-01

Safety behaviour plays an important role in the maintenance of social anxiety disorder (SAD). SAD patients engage in various safety behaviours in social situations in order to decrease the risk of negative evaluations from others. The present study examined the effect of safety behaviour on the maintenance of anxiety and negative belief in SAD by using Structural Equation Modelling (SEM). Participants were a healthy group (442) and a SAD group (46) who met the SAD criteria for DSM-IV and who had high scores of SAD symptoms. In the assumed maintenance model, independence variables were safety and avoidance behaviour and dependence variables were anxiety and negative belief. This result showed that the SAD group significantly has more high scores than the healthy group in all scales of anxiety, negative belief and avoidance behaviour, expect for safety behaviour. The result of the multiple-group procedure indicated that safety behaviour contributes more strongly to anxiety and negative belief in the SAD group than in the healthy group. It is speculated that the SAD group have a stronger link between safety behaviour and negative belief than the healthy group, whereas frequency of the use of safety behaviour is equivalent between two groups. These results support the findings of previous studies.

Socioeconomic inequalities in cause specific mortality among older people in France.

PubMed

Menvielle, Gwenn; Leclerc, Annette; Chastang, Jean-François; Luce, Danièle

2010-05-19

European comparative studies documented a clear North-South divide in socioeconomic inequalities with cancer being the most important contributor to inequalities in total mortality among middle aged men in Latin Europe (France, Spain, Portugal, Italy). The aim of this paper is to investigate educational inequalities in mortality by gender, age and causes of death in France, with a special emphasis on people aged 75 years and more. We used data from a longitudinal population sample that includes 1% of the French population. Risk of death (total and cause specific) in the period 1990-1999 according to education was analysed using Cox regression models by age group (45-59, 60-74, and 75+). Inequalities were quantified using both relative (ratio) and absolute (difference) measures. Relative inequalities decreased with age but were still observed in the oldest age group. Absolute inequalities increased with age. This increase was particularly pronounced for cardiovascular diseases. The contribution of different causes of death to absolute inequalities in total mortality differed between age groups. In particular, the contribution of cancer deaths decreased substantially between the age groups 60-74 years and 75 years and more, both in men and in women. This study suggests that the large contribution of cancer deaths to the excess mortality among low educated people that was observed among middle aged men in Latin Europe is not observed among French people aged 75 years and more. This should be confirmed among other Latin Europe countries.

Barriers to nurse entrepreneurship: a study of the process model of entrepreneurship.

PubMed

Elango, B; Hunter, Gary L; Winchell, Mike

2007-04-01

The potential for nurse entrepreneurship to contribute to the effectiveness of healthcare delivery is well acknowledged, yet it has not been fully realized. Using the process model of entrepreneurship, we attempted to glean information from nursing professionals through focus groups on the barriers to starting a business. Two focus groups were used and expert moderators conducted these exercises. The first focus group included two hospital administrators, a nurse entrepreneur, an ophthalmology entrepreneur, and a dean of the nursing school familiar with nurse entrepreneurship. The second focus group used 20 students in a nurse practitioner program. The study findings indicate nurse practitioners and other nursing professionals do recognize the potential of nurse entrepreneurship. However, several barriers prevent them from exploiting the identified opportunity. While the barriers are significant, we believe they can be overcome with coordinated action by individual nurses, professional associations, and public policy initiatives. Several suggestions are offered to nurses seeking to become nurse entrepreneurs.

Amination of activated carbon for enhancing phenol adsorption: Effect of nitrogen-containing functional groups

NASA Astrophysics Data System (ADS)

Yang, Guo; Chen, Honglin; Qin, Hangdao; Feng, Yujun

2014-02-01

To study the contribution of different nitrogen-containing functional groups to enhancement of phenol adsorption, the aminated activated carbons (AC) were characterized by N2 adsorption/desorption, XPS, Boehm titration, and pH drift method and tested for adsorption behaviors of phenol. Adsorption isotherm fitting revealed that the Langmuir model was preferred for the aminated ACs. The adsorption capacity per unit surface area (qm/SSABET) was linearly correlated with the amount of pyridinic and pyrrolic N, which suggested that these two functional groups played a critical role in phenol adsorption. The enhancement of adsorption capacity was attributed to the strengthened π-π dispersion between phenol and basal plane of AC by pyridinic, pyrrolic N. The adsorption kinetics was found to follow the pseudo-second-order kinetic model, and intraparticle diffusion was one of the rate-controlling steps in the adsorption process.

Vithanage Receives 2009 Natural Hazards Focus Group Award for Graduate Research

NASA Astrophysics Data System (ADS)

2010-04-01

Meththika Vithanage has been awarded the Natural Hazards Focus Group Award for Graduate Research, given annually to recent Ph.D. recipients for outstanding contributions to natural hazards research. Vithanage’s thesis is entitled “Effect of tsunami on coastal aquifers: Field studies and tank experiments.” She was formally presented with the award at the Natural Hazards Focus Group reception during the 2009 AGU Fall Meeting, held 14-18 December in San Francisco, Calif. Vithanage received her B.S. in natural resources from Sabaragamuwa University of Sri Lanka in 2002 and an M.S. in environmental science from the University of Peradeniya, Sri Lanka, in 2005. In 2009, she attained a Ph.D. in hydrogeology under the supervision of Karsten Jensen and Peter Engesgaard in the Department of Geology and Geography at University of Copenhagen, Denmark. Her research interests include groundwater flow modeling, density-dependent flow and solute transport modeling, and water quality analysis.

An Integrative Approach to Computational Modelling of the Gene Regulatory Network Controlling Clostridium botulinum Type A1 Toxin Production.

PubMed

Ihekwaba, Adaoha E C; Mura, Ivan; Walshaw, John; Peck, Michael W; Barker, Gary C

2016-11-01

Clostridium botulinum produces botulinum neurotoxins (BoNTs), highly potent substances responsible for botulism. Currently, mathematical models of C. botulinum growth and toxigenesis are largely aimed at risk assessment and do not include explicit genetic information beyond group level but integrate many component processes, such as signalling, membrane permeability and metabolic activity. In this paper we present a scheme for modelling neurotoxin production in C. botulinum Group I type A1, based on the integration of diverse information coming from experimental results available in the literature. Experiments show that production of BoNTs depends on the growth-phase and is under the control of positive and negative regulatory elements at the intracellular level. Toxins are released as large protein complexes and are associated with non-toxic components. Here, we systematically review and integrate those regulatory elements previously described in the literature for C. botulinum Group I type A1 into a population dynamics model, to build the very first computational model of toxin production at the molecular level. We conduct a validation of our model against several items of published experimental data for different wild type and mutant strains of C. botulinum Group I type A1. The result of this process underscores the potential of mathematical modelling at the cellular level, as a means of creating opportunities in developing new strategies that could be used to prevent botulism; and potentially contribute to improved methods for the production of toxin that is used for therapeutics.

Alien calculus and a Schwinger-Dyson equation: two-point function with a nonperturbative mass scale

NASA Astrophysics Data System (ADS)

Bellon, Marc P.; Clavier, Pierre J.

2018-02-01

Starting from the Schwinger-Dyson equation and the renormalization group equation for the massless Wess-Zumino model, we compute the dominant nonperturbative contributions to the anomalous dimension of the theory, which are related by alien calculus to singularities of the Borel transform on integer points. The sum of these dominant contributions has an analytic expression. When applied to the two-point function, this analysis gives a tame evolution in the deep euclidean domain at this approximation level, making doubtful the arguments on the triviality of the quantum field theory with positive β -function. On the other side, we have a singularity of the propagator for timelike momenta of the order of the renormalization group invariant scale of the theory, which has a nonperturbative relationship with the renormalization point of the theory. All these results do not seem to have an interpretation in terms of semiclassical analysis of a Feynman path integral.

Understanding how social networking influences perceived satisfaction with conference experiences

USGS Publications Warehouse

van Riper, Carena J.; van Riper, Charles; Kyle, Gerard T.; Lee, Martha E.

2013-01-01

Social networking is a key benefit derived from participation in conferences that bind the ties of a professional community. Building social networks can lead to satisfactory experiences while furthering participants' long- and short-term career goals. Although investigations of social networking can lend insight into how to effectively engage individuals and groups within a professional cohort, this area has been largely overlooked in past research. The present study investigates the relationship between social networking and satisfaction with the 10th Biennial Conference of Research on the Colorado Plateau using structural equation modelling. Results partially support the hypothesis that three dimensions of social networking – interpersonal connections, social cohesion, and secondary associations – positively contribute to the performance of various conference attributes identified in two focus group sessions. The theoretical and applied contributions of this paper shed light on the social systems formed within professional communities and resource allocation among service providers.

Logical Modeling and Dynamical Analysis of Cellular Networks

PubMed Central

Abou-Jaoudé, Wassim; Traynard, Pauline; Monteiro, Pedro T.; Saez-Rodriguez, Julio; Helikar, Tomáš; Thieffry, Denis; Chaouiya, Claudine

2016-01-01

The logical (or logic) formalism is increasingly used to model regulatory and signaling networks. Complementing these applications, several groups contributed various methods and tools to support the definition and analysis of logical models. After an introduction to the logical modeling framework and to several of its variants, we review here a number of recent methodological advances to ease the analysis of large and intricate networks. In particular, we survey approaches to determine model attractors and their reachability properties, to assess the dynamical impact of variations of external signals, and to consistently reduce large models. To illustrate these developments, we further consider several published logical models for two important biological processes, namely the differentiation of T helper cells and the control of mammalian cell cycle. PMID:27303434

Investigation of the Effect of Milrinone on Renal Damage in an Experimental Non-Heart Beating Donor Model.

PubMed

Uysal, Erdal; Dokur, Mehmet; Altınay, Serdar; Saygılı, Eyup İlker; Batcıoglu, Kadir; Ceylan, Mehmet S; Kazımoglu, Hatem; Uyumlu, Burcin A; Karadag, Mehmet

2017-07-14

In our study, it was aimed to investigate the preventive effect of milrinone on renal damage in experimental controlled non-heart-beating donors (NHBDs) model. Sixteen rats randomly divided into 2 groups, 8 rats in each were used. Group 1 was control, group 2 was milrinone group. Group 1 rats received 1.25 ml 0.09% NaCl intraperitoneally equivalent to the milrinone diluted volume. Group 2 rats were administered intraperitoneally with 0.5 mg/kg of milrinone 2 hours before cardiac arrest. After the cardiac arrest, left nephrectomy was applied to the rats. Malondialdehyde, superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx) activities, Caspase-3 (apoptotic index) and histopathological evaluation were performed in the tissues. In the milrinone group, the total injury score was significantly lower relative to the control group (p = 0.001). Caspase-3 staining was moderately strong in the control group but weaker in the milrinone group. Apoptotic index was significantly lower in the milrinone group compared to the control group (p = 0.001). In comparison between groups, SOD and GPx in the milrinone group was significantly higher than the control group (p = 0.008, p = 0.006). Milrinone has been shown to be effective in the prevention of tissue damage due to oxidative stress and inflammatory process in the renal of warm ischemia in the experimental NHBDs model and in protecting the renal. Milrinone increases antioxidant activity while reducing apoptosis. Systemic administration of milrinone prior to cardiac arrest may be beneficial. Administration of milrinone to the recipient in the perioperative period may contribute to donor function.

Acceptability and Feasibility of a Shared Decision-Making Model in Work Rehabilitation: A Mixed-Methods Study of Stakeholders' Perspectives.

PubMed

Coutu, Marie-France; Légaré, France; Durand, Marie-José; Stacey, Dawn; Labrecque, Marie-Elise; Corbière, Marc; Bainbridge, Lesley

2018-04-16

Purpose To establish the acceptability and feasibility of implementing a shared decision-making (SDM) model in work rehabilitation. Methods We used a sequential mixed-methods design with diverse stakeholder groups (representatives of private and public employers, insurers, and unions, as well as workers having participated in a work rehabilitation program). First, a survey using a self-administered questionnaire enabled stakeholders to rate their level of agreement with the model's acceptability and feasibility and propose modifications, if necessary. Second, eight focus groups representing key stakeholders (n = 34) and four one-on-one interviews with workers were conducted, based on the questionnaire results. For each stakeholder group, we computed the percentage of agreement with the model's acceptability and feasibility and performed thematic analyses of the transcripts. Results Less than 50% of each stakeholder group initially agreed with the overall acceptability and feasibility of the model. Stakeholders proposed 37 modifications to the objectives, 17 to the activities, and 39 to improve the model's feasibility. Based on in-depth analysis of the transcripts, indicators were added to one objective, an interview guide was added as proposed by insurers to ensure compliance of the SDM process with insurance contract requirements, and one objective was reformulated. Conclusion Despite initially low agreement with the model's acceptability on the survey, subsequent discussions led to three minor changes and contributed to the model's ultimate acceptability and feasibility. Later steps will involve assessing the extent of implementation of the model in real rehabilitation settings to see if other modifications are necessary before assessing its impact.

Meal types as sources for intakes of fruits, vegetables, fish and whole grains among Norwegian adults.

PubMed

Myhre, Jannicke B; Løken, Elin B; Wandel, Margareta; Andersen, Lene F

2015-08-01

To study how different meals contribute to intakes of fruits, vegetables, fish and whole grains in a group of Norwegian adults and in subgroups of this population. Moreover, to investigate the consequences of skipping the meal contributing most to the intake of each food group (main contributing meal). Cross-sectional dietary survey in Norwegian adults. Dietary data were collected using two non-consecutive telephone-administered 24 h recalls. The recorded meal types were breakfast, lunch, dinner, supper/evening meal and snacks. Nationwide, Norway (2010-2011). Adults aged 18-70 years (n 1787). Dinner was the main contributing meal for fish and vegetables, while snacks were the main contributing meal for fruit intake. For whole grains, breakfast was the main contributing meal. The main contributing meal did not change for any of the food groups when studying subgroups of the participants according to intake of each food group, educational level or age. A substantially lower intake of the food groups in question was found on days when the main contributing meal was skipped. Intakes of fruits, vegetables, fish and whole grains largely depend on one meal type. Inclusion of these foods in other meals in addition to the main contributing meal, preferably replacing energy-dense nutrient-poor foods, should be promoted.

MECHANISMS OF COIX SEED COMPOSITIONS IN THE TREATMENT OF SPLEEN DEFICIENCY AND WET DAMPNESS ZHENG.

PubMed

Han, Xiaochun; Ji, Xuming; Zhao, Haijun; Zhang, Yanan; Liu, Guowei; Wang, Yanfang; Zhao, Wenxiao; Wang, Shijun

2017-01-01

Coix seed has the functions of fortifying the spleen and inhibiting the dampness. However, it remains unclear which Coix seed compositions is responsible for these functions. Previous investigations have revealed that the main compositions of Coix seed are proteins, polysaccharides, oils and starches. The objectives of this study are to explore which is the most effective compositions in fortifying the spleen and examine how Coix seed works in regulating the water transport on the spleen deficiency and wet dampness (SDWD) rat model. The rats used were divided into (i) control group, (ii) model group, (iii) decoction group, (iv) protein group, (v) polysaccharide group, (vi) oil group and (vii) starch group. The urine volume, the drinking volume and the water loading index in each group were calculated. Agilent 8*60K array was used for microarray-based gene expression analysis. The differential mRNAs related to the transport activity were screened. qRT-PCR was used to validate the mRNA microarray. The results demonstrated that all treatment groups could decrease the dampness of SDWD rats. mRNA microarray had significant effect on the protein group and the polysaccharide group in regulating the water transport, among which the most significant mRNA was Fabp6, Slc51a, Slc51b, Slc11a2, Slc4a10 and AQP3 respectively. The compositions of proteins and polysaccharides had the most significant effect in regulating the water transport of SDWD rat model. The contributing mRNA focused on Fabp, Slc and AQP family.

Computational reverse shoulder prosthesis model: Experimental data and verification.

PubMed

Martins, A; Quental, C; Folgado, J; Ambrósio, J; Monteiro, J; Sarmento, M

2015-09-18

The reverse shoulder prosthesis aims to restore the stability and function of pathological shoulders, but the biomechanical aspects of the geometrical changes induced by the implant are yet to be fully understood. Considering a large-scale musculoskeletal model of the upper limb, the aim of this study is to evaluate how the Delta reverse shoulder prosthesis influences the biomechanical behavior of the shoulder joint. In this study, the kinematic data of an unloaded abduction in the frontal plane and an unloaded forward flexion in the sagittal plane were experimentally acquired through video-imaging for a control group, composed of 10 healthy shoulders, and a reverse shoulder group, composed of 3 reverse shoulders. Synchronously, the EMG data of 7 superficial muscles were also collected. The muscle force sharing problem was solved through the minimization of the metabolic energy consumption. The evaluation of the shoulder kinematics shows an increase in the lateral rotation of the scapula in the reverse shoulder group, and an increase in the contribution of the scapulothoracic joint to the shoulder joint. Regarding the muscle force sharing problem, the musculoskeletal model estimates an increased activity of the deltoid, teres minor, clavicular fibers of the pectoralis major, and coracobrachialis muscles in the reverse shoulder group. The comparison between the muscle forces predicted and the EMG data acquired revealed a good correlation, which provides further confidence in the model. Overall, the shoulder joint reaction force was lower in the reverse shoulder group than in the control group. Copyright © 2015 Elsevier Ltd. All rights reserved.

In-group defense, out-group aggression, and coordination failures in intergroup conflict.

PubMed

De Dreu, Carsten K W; Gross, Jörg; Méder, Zsombor; Giffin, Michael; Prochazkova, Eliska; Krikeb, Jonathan; Columbus, Simon

2016-09-20

Intergroup conflict persists when and because individuals make costly contributions to their group's fighting capacity, but how groups organize contributions into effective collective action remains poorly understood. Here we distinguish between contributions aimed at subordinating out-groups (out-group aggression) from those aimed at defending the in-group against possible out-group aggression (in-group defense). We conducted two experiments in which three-person aggressor groups confronted three-person defender groups in a multiround contest game (n = 276; 92 aggressor-defender contests). Individuals received an endowment from which they could contribute to their group's fighting capacity. Contributions were always wasted, but when the aggressor group's fighting capacity exceeded that of the defender group, the aggressor group acquired the defender group's remaining resources (otherwise, individuals on both sides were left with the remainders of their endowment). In-group defense appeared stronger and better coordinated than out-group aggression, and defender groups survived roughly 70% of the attacks. This low success rate for aggressor groups mirrored that of group-hunting predators such as wolves and chimpanzees (n = 1,382 cases), hostile takeovers in industry (n = 1,637 cases), and interstate conflicts (n = 2,586). Furthermore, whereas peer punishment increased out-group aggression more than in-group defense without affecting success rates (Exp. 1), sequential (vs. simultaneous) decision-making increased coordination of collective action for out-group aggression, doubling the aggressor's success rate (Exp. 2). The relatively high success rate of in-group defense suggests evolutionary and cultural pressures may have favored capacities for cooperation and coordination when the group goal is to defend, rather than to expand, dominate, and exploit.

Ethnicity and cultural models of recovery from breast cancer.

PubMed

Coreil, Jeannine; Corvin, Jaime A; Nupp, Rebecca; Dyer, Karen; Noble, Charlotte

2012-01-01

Recovery narratives describe the culturally shared understandings about the ideal or desirable way to recover from an illness experience. This paper examines ethnic differences in recovery narratives among women participating in breast cancer support groups in Central Florida, USA. It compares groups serving African-American, Latina, and European American women, with the objective of better understanding the appeal of ethnic-specific illness support groups for culturally diverse populations. A mixed-method study design combined qualitative and quantitative measures, including in-depth interviews, participant observation at support group meetings, collection of printed documents, and a structured survey. Core elements of the recovery narrative drew from the dominant societal cancer discourse of optimism and personal transformation through adversity; however, important ethnic differences were evident in the meaning assigned to these themes. Groups gave distinctive salience to themes of faith and spirituality, empowerment through the migration experience, and becoming a better person through the journey of recovery. The findings suggest that ethnic cancer support groups draw upon dominant societal discourses about cancer, but they espouse distinctive recovery narratives that are consonant with the groups' cultural models of illness. Similarity between ethnic members' individual recovery narratives and that of the group may contribute to the appeal of ethnic illness support groups for culturally diverse populations.

COMPASS: A computational model to predict changes in MMSE scores 24-months after initial assessment of Alzheimer's disease.

PubMed

Zhu, Fan; Panwar, Bharat; Dodge, Hiroko H; Li, Hongdong; Hampstead, Benjamin M; Albin, Roger L; Paulson, Henry L; Guan, Yuanfang

2016-10-05

We present COMPASS, a COmputational Model to Predict the development of Alzheimer's diSease Spectrum, to model Alzheimer's disease (AD) progression. This was the best-performing method in recent crowdsourcing benchmark study, DREAM Alzheimer's Disease Big Data challenge to predict changes in Mini-Mental State Examination (MMSE) scores over 24-months using standardized data. In the present study, we conducted three additional analyses beyond the DREAM challenge question to improve the clinical contribution of our approach, including: (1) adding pre-validated baseline cognitive composite scores of ADNI-MEM and ADNI-EF, (2) identifying subjects with significant declines in MMSE scores, and (3) incorporating SNPs of top 10 genes connected to APOE identified from functional-relationship network. For (1) above, we significantly improved predictive accuracy, especially for the Mild Cognitive Impairment (MCI) group. For (2), we achieved an area under ROC of 0.814 in predicting significant MMSE decline: our model has 100% precision at 5% recall, and 91% accuracy at 10% recall. For (3), "genetic only" model has Pearson's correlation of 0.15 to predict progression in the MCI group. Even though addition of this limited genetic model to COMPASS did not improve prediction of progression of MCI group, the predictive ability of SNP information extended beyond well-known APOE allele.

Contributing to Meaning Making: Facilitating Discourse in the High School Physics Classroom

NASA Astrophysics Data System (ADS)

Hovan, Scot Alan

The Next Generation Science Standards (NGSS) identify eight practices as essential to science and engineering, and these practices include asking students to construct explanations, to engage in argumentation, and to communicate scientific information. However, few teacher-training programs instruct teachers how to facilitate such discourse in the classroom. Modeling Instruction is one movement in physics education that organizes high school physics content around a small number of student-derived scientific models, and it relies on student discourse for the design, development, and deployment of these models. This research is a self-study of one high school physics teacher's experience facilitating large group discourse in the high school modeling physics classroom. Whiteboard meetings and graded discussions were examined by applying the analytical framework created by Mortimer and Scott (2003) to characterize the classroom talk and the discourse facilitation moves that I employed. In addition, elements of discourse analysis were used to examine some of the tensions that I experienced in the facilitation of this discourse. The findings suggest that deliberate identification of the teaching purposes for the discussion can help determine the scaffolding needed for students to enter the Discourse (Gee, 2011) of being a participant in these large group conversations. In addition, connecting the dialogic dimension of exploring student ideas with the authoritative dimension of introducing the scientific view and supporting the internalization of that view is necessary to contribute to meaning making in the science classroom.

A Memory-Process Model of Symbolic Assimilation

DTIC Science & Technology

1974-04-01

Systems: Final Report of a Study Group, published for Artificial Intellegence by North-Holland/Amorican...contribution of the methods is answered by evaluating the same program in the context of the field of artificial intelligence. The remainder of the...been widely demonstrated on a diversity of tasks in tha history of artificial intelligence. See [r.71], chapter 2. Given a particular task to be

The Contribution of the Insula to Motor Aspects of Speech Production: A Review and a Hypothesis

ERIC Educational Resources Information Center

Ackermann, Hermann; Riecker, Axel

2004-01-01

Based on clinical and functional imaging data, the left anterior insula has been assumed to support prearticulatory functions of speech motor control such as the ''programming'' of vocal tract gestures. In order to further elucidate this model, a recent functional magnetic resonance imaging (fMRI) study of our group (Riecker, Ackermann,…

Risky Lifestyle as a Mediator of the Relationship between Deviant Peer Affiliation and Dating Violence Victimization among Adolescent Girls

ERIC Educational Resources Information Center

Vezina, Johanne; Hebert, Martine; Poulin, Francois; Lavoie, Francine; Vitaro, Frank; Tremblay, Richard E.

2011-01-01

Few studies have explored the possible contribution of the peer group to dating violence victimization. The current study tested the hypothesis that a risky lifestyle would mediate the relationship between deviant peer affiliation and dating violence victimization among adolescent girls. The proposed mediation model was derived from lifestyles and…

Toward a Model of Influence in Persuasive Discussions: Negotiating Quality, Authority, Privilege, and Access within a Student-Led Argument

ERIC Educational Resources Information Center

Engle, Randi A.; Langer-Osuna, Jennifer M.; McKinney de Royston, Maxine

2014-01-01

It is commonly observed that during classroom or group discussions some students have greater influence than may be justified by the normative quality of those students' contributions. We propose a 5-component theoretical framework in order to explain how undue influence unfolds. We build on literatures on persuasion, argumentation, discourse, and…

A recovery journey for people with personality disorder.

PubMed

Castillo, Heather; Ramon, Shulamit; Morant, Nicola

2013-05-01

The study investigates the process of recovery for people diagnosed with personality disorder, a client group that suffers significant social exclusion known to impact on demand for health and other public services. It aims to examine efforts that attempt to reverse this social exclusion as an aspect of the recovery process. and The following study aims to (1) explore what recovery means to people with personality disorder; (2) develop a conceptual model of recovery in personality disorder; and (3) evaluate the contribution of the setting (The Haven) to recovery practice. The study uses a Participatory Action Research (PAR) design. Data was collected from 66 participants by focus groups and individual interviews. A map based on thematic analysis of data collected during the study is proposed of the recovery journey for people with this diagnosis, shown as a pyramid that represents a hierarchy of progress, from building trust through stages of recovery to social inclusion. The findings offer contributions to knowledge in terms of the service design and propose a new model of recovery in personality disorder. This is defined as a journey of small steps highlighting recovery as a process rather than a goal, leading to the emergence of the new concept of transitional recovery.

Modeling the contribution of personality, social identity and social norms to problematic Facebook use in adolescents.

PubMed

Marino, Claudia; Vieno, Alessio; Pastore, Massimiliano; Albery, Ian P; Frings, Daniel; Spada, Marcantonio M

2016-12-01

Facebook is the most popular social networking site in the world providing the opportunity to maintain and/or establish relationships, to share media contents and experiences with friends, and to easily communicate with them. Despite the resources and the innovative social features offered by Facebook research has emerged indicating that its use may become problematic, with negative consequences on personal psycho-social well-being, especially among adolescents and young adults. The main aim of this study was to examine the unique contribution of personality traits and social influence processes (i.e. subjective norms, group norms, and social identity) to perceived frequency of Facebook Use and Problematic Facebook Use in a sample of adolescents. A total of 968 Italian adolescents participated in the study. Structural equation modeling showed that emotional stability, extraversion, conscientiousness and norms directly predicted Problematic Facebook Use, whereas gender, group norms and social identity predicted perceived frequency of Facebook use. In conclusion, both personal and social variables appear to explain perceived frequency of Facebook use and Problematic Facebook Use among adolescents, and should be taken into account by researchers and educational practitioners. Copyright © 2016 Elsevier Ltd. All rights reserved.

General Aviation Interior Noise. Part 1; Source/Path Identification

NASA Technical Reports Server (NTRS)

Unruh, James F.; Till, Paul D.; Palumbo, Daniel L. (Technical Monitor)

2002-01-01

There were two primary objectives of the research effort reported herein. The first objective was to identify and evaluate noise source/path identification technology applicable to single engine propeller driven aircraft that can be used to identify interior noise sources originating from structure-borne engine/propeller vibration, airborne propeller transmission, airborne engine exhaust noise, and engine case radiation. The approach taken to identify the contributions of each of these possible sources was first to conduct a Principal Component Analysis (PCA) of an in-flight noise and vibration database acquired on a Cessna Model 182E aircraft. The second objective was to develop and evaluate advanced technology for noise source ranking of interior panel groups such as the aircraft windshield, instrument panel, firewall, and door/window panels within the cabin of a single engine propeller driven aircraft. The technology employed was that of Acoustic Holography (AH). AH was applied to the test aircraft by acquiring a series of in-flight microphone array measurements within the aircraft cabin and correlating the measurements via PCA. The source contributions of the various panel groups leading to the array measurements were then synthesized by solving the inverse problem using the boundary element model.

Dietary supplementation with sorbitol results in selective enrichment of lactobacilli in rat intestine.

PubMed

Sarmiento-Rubiano, Luz Adriana; Zúñiga, Manuel; Pérez-Martínez, Gaspar; Yebra, María Jesús

2007-01-01

A potential prebiotic action has been ascribed to sorbitol, but in vivo evidence of this remains scarce. In the present work, the effect of sorbitol was compared to that of fructo-oligosaccharides (FOS) in a rat model. Microbiota changes, particularly in lactobacilli, were analyzed on fecal, colonic and cecal samples. Denaturing gradient gel electrophoresis (DGGE) analysis of 16S rRNA gene amplicons using universal primers showed that FOS and sorbitol diets exerted a strong influence upon gut microbiota patterns. When Lactobacillus group-specific primers were used, DGGE profiles revealed five DNA bands that belonged to Lactobacillus johnsonii, Lactobacillus sp. AD102, Lactobacillus intestinalis, Lactobacillus murinus and Lactobacillus reuteri. Although these species are present in all dietary groups, quantification by real-time PCR showed that sorbitol and FOS intake increased L. reuteri cell numbers, and sorbitol also contributed to maintaining the levels of Lactobacillus sp. AD102. Analysis of organic acid concentrations showed that sorbitol intake significantly increased colonic and cecal butyrate levels. Hence, sorbitol, which is widely used as a low-calorie sweetener, has the capacity, in our animal model, to modify gut microbiota activity in such a way as to possibly contribute to healthy colonic mucosa.

Asymptomatic Carriage of Group A Streptococcus Is Associated with Elimination of Capsule Production

PubMed Central

Jewell, Brittany E.; Olsen, Randall J.; Shelburne, Samuel A.; Fittipaldi, Nahuel; Beres, Stephen B.; Musser, James M.

2014-01-01

Humans commonly carry pathogenic bacteria asymptomatically, but despite decades of study, the underlying molecular contributors remain poorly understood. Here, we show that a group A streptococcus carriage strain contains a frameshift mutation in the hasA gene resulting in loss of hyaluronic acid capsule biosynthesis. This mutation was repaired by allelic replacement, resulting in restoration of capsule production in the isogenic derivative strain. The “repaired” isogenic strain was significantly more virulent than the carriage strain in a mouse model of necrotizing fasciitis and had enhanced growth ex vivo in human blood. Importantly, the repaired isogenic strain colonized the mouse oropharynx with significantly greater bacterial burden and had significantly reduced ability to internalize into cultured epithelial cells than the acapsular carriage strain. We conducted full-genome sequencing of 81 strains cultured serially from 19 epidemiologically unrelated human subjects and discovered the common theme that mutations negatively affecting capsule biosynthesis arise in vivo in the has operon. The significantly decreased capsule production is a key factor contributing to the molecular détente between pathogen and host. Our discoveries suggest a general model for bacterial pathogens in which mutations that downregulate or ablate virulence factor production contribute to carriage. PMID:25024363

Dilemma of dilemmas: how collective and individual perspectives can clarify the size dilemma in voluntary linear public goods dilemmas.

PubMed

Shank, Daniel B; Kashima, Yoshihisa; Saber, Saam; Gale, Thomas; Kirley, Michael

2015-01-01

Empirical findings on public goods dilemmas indicate an unresolved dilemma: that increasing size-the number of people in the dilemma-sometimes increases, decreases, or does not influence cooperation. We clarify this dilemma by first classifying public goods dilemma properties that specify individual outcomes as individual properties (e.g., Marginal Per Capita Return) and group outcomes as group properties (e.g., public good multiplier), mathematically showing how only one set of properties can remain constant as the dilemma size increases. Underpinning decision-making regarding individual and group properties, we propose that individuals are motivated by both individual and group preferences based on a theory of collective rationality. We use Van Lange's integrated model of social value orientations to operationalize these preferences as an amalgamation of outcomes for self, outcomes for others, and equality of outcomes. Based on this model, we then predict how the public good's benefit and size, combined with controlling individual versus group properties, produce different levels of cooperation in public goods dilemmas. A two (low vs. high benefit) by three (2-person baseline vs. 5-person holding constant individual properties vs. 5-person holding constant group properties) factorial experiment (group n = 99; participant n = 390) confirms our hypotheses. The results indicate that when holding constant group properties, size decreases cooperation. Yet when holding constant individual properties, size increases cooperation when benefit is low and does not affect cooperation when benefit is high. Using agent-based simulations of individual and group preferences vis-à-vis the integrative model, we fit a weighted simulation model to the empirical data. This fitted model is sufficient to reproduce the empirical results, but only when both individual (self-interest) and group (other-interest and equality) preference are included. Our research contributes to understanding how people's motivations and behaviors within public goods dilemmas interact with the properties of the dilemma to lead to collective outcomes.

Dilemma of Dilemmas: How Collective and Individual Perspectives Can Clarify the Size Dilemma in Voluntary Linear Public Goods Dilemmas

PubMed Central

Shank, Daniel B.; Kashima, Yoshihisa; Saber, Saam; Gale, Thomas; Kirley, Michael

2015-01-01

Empirical findings on public goods dilemmas indicate an unresolved dilemma: that increasing size—the number of people in the dilemma—sometimes increases, decreases, or does not influence cooperation. We clarify this dilemma by first classifying public goods dilemma properties that specify individual outcomes as individual properties (e.g., Marginal Per Capita Return) and group outcomes as group properties (e.g., public good multiplier), mathematically showing how only one set of properties can remain constant as the dilemma size increases. Underpinning decision-making regarding individual and group properties, we propose that individuals are motivated by both individual and group preferences based on a theory of collective rationality. We use Van Lange's integrated model of social value orientations to operationalize these preferences as an amalgamation of outcomes for self, outcomes for others, and equality of outcomes. Based on this model, we then predict how the public good's benefit and size, combined with controlling individual versus group properties, produce different levels of cooperation in public goods dilemmas. A two (low vs. high benefit) by three (2-person baseline vs. 5-person holding constant individual properties vs. 5-person holding constant group properties) factorial experiment (group n = 99; participant n = 390) confirms our hypotheses. The results indicate that when holding constant group properties, size decreases cooperation. Yet when holding constant individual properties, size increases cooperation when benefit is low and does not affect cooperation when benefit is high. Using agent-based simulations of individual and group preferences vis-à-vis the integrative model, we fit a weighted simulation model to the empirical data. This fitted model is sufficient to reproduce the empirical results, but only when both individual (self-interest) and group (other-interest and equality) preference are included. Our research contributes to understanding how people's motivations and behaviors within public goods dilemmas interact with the properties of the dilemma to lead to collective outcomes. PMID:25799355

Modeling individual differences in text reading fluency: a different pattern of predictors for typically developing and dyslexic readers

PubMed Central

Zoccolotti, Pierluigi; De Luca, Maria; Marinelli, Chiara V.; Spinelli, Donatella

2014-01-01

This study was aimed at predicting individual differences in text reading fluency. The basic proposal included two factors, i.e., the ability to decode letter strings (measured by discrete pseudo-word reading) and integration of the various sub-components involved in reading (measured by Rapid Automatized Naming, RAN). Subsequently, a third factor was added to the model, i.e., naming of discrete digits. In order to use homogeneous measures, all contributing variables considered the entire processing of the item, including pronunciation time. The model, which was based on commonality analysis, was applied to data from a group of 43 typically developing readers (11- to 13-year-olds) and a group of 25 chronologically matched dyslexic children. In typically developing readers, both orthographic decoding and integration of reading sub-components contributed significantly to the overall prediction of text reading fluency. The model prediction was higher (from ca. 37 to 52% of the explained variance) when we included the naming of discrete digits variable, which had a suppressive effect on pseudo-word reading. In the dyslexic readers, the variance explained by the two-factor model was high (69%) and did not change when the third factor was added. The lack of a suppression effect was likely due to the prominent individual differences in poor orthographic decoding of the dyslexic children. Analyses on data from both groups of children were replicated by using patches of colors as stimuli (both in the RAN task and in the discrete naming task) obtaining similar results. We conclude that it is possible to predict much of the variance in text-reading fluency using basic processes, such as orthographic decoding and integration of reading sub-components, even without taking into consideration higher-order linguistic factors such as lexical, semantic and contextual abilities. The approach validity of using proximal vs. distal causes to predict reading fluency is discussed. PMID:25477856

Dissociable meta-analytic brain networks contribute to coordinated emotional processing.

PubMed

Riedel, Michael C; Yanes, Julio A; Ray, Kimberly L; Eickhoff, Simon B; Fox, Peter T; Sutherland, Matthew T; Laird, Angela R

2018-06-01

Meta-analytic techniques for mining the neuroimaging literature continue to exert an impact on our conceptualization of functional brain networks contributing to human emotion and cognition. Traditional theories regarding the neurobiological substrates contributing to affective processing are shifting from regional- towards more network-based heuristic frameworks. To elucidate differential brain network involvement linked to distinct aspects of emotion processing, we applied an emergent meta-analytic clustering approach to the extensive body of affective neuroimaging results archived in the BrainMap database. Specifically, we performed hierarchical clustering on the modeled activation maps from 1,747 experiments in the affective processing domain, resulting in five meta-analytic groupings of experiments demonstrating whole-brain recruitment. Behavioral inference analyses conducted for each of these groupings suggested dissociable networks supporting: (1) visual perception within primary and associative visual cortices, (2) auditory perception within primary auditory cortices, (3) attention to emotionally salient information within insular, anterior cingulate, and subcortical regions, (4) appraisal and prediction of emotional events within medial prefrontal and posterior cingulate cortices, and (5) induction of emotional responses within amygdala and fusiform gyri. These meta-analytic outcomes are consistent with a contemporary psychological model of affective processing in which emotionally salient information from perceived stimuli are integrated with previous experiences to engender a subjective affective response. This study highlights the utility of using emergent meta-analytic methods to inform and extend psychological theories and suggests that emotions are manifest as the eventual consequence of interactions between large-scale brain networks. © 2018 Wiley Periodicals, Inc.

The role of relationships in collaborative partnership success: Lessons from the Alaska Fourth R project.

PubMed

Crooks, Claire V; Exner-Cortens, Deinera; Siebold, Wendi; Moore, Kami; Grassgreen, Lori; Owen, Patricia; Rausch, Ann; Rosier, Mollie

2018-04-01

Collaborative partnerships are critical to achieving health equity. As such, it is important to understand what contributes to the success of such partnerships. This paper describes the Alaska Fourth R collaborative, a multisectoral group of agencies (including education, health and human services, the violence against women sector, the governor's council on domestic violence, and an external evaluator) that successfully planned, implemented and evaluated a multi-focus health education program statewide. The purpose of this paper was to explore the ways in which seven pre-identified factors contributed to the successful achievement of the collaborative's goals. This project was grounded in community-based research principles, and collectively, the group chose to use Roussos and Fawcett's (2000) seven-factor model as the basis for the project. Using this model as a guide, semi-structured interviews were conducted with five leaders from the key organizations in the collaborative. In interviews, stakeholders described how each of the seven factors functioned in the Alaska collaborative to contribute to project success, with a particular focus on the critical role of relationships. Three specific relationship facets emerged as cross-cutting themes: flexibility, transparency, and prioritization. In sum, taking the time to build deep and authentic relationships, and then developing a shared vision and mission within the context of relationships that are flexible, transparent and prioritized, provided a strong foundation for future success in this collaborative. Copyright © 2017 Elsevier Ltd. All rights reserved.

Singularity-free next-to-leading order ΔS = 1 renormalization group evolution and ɛ K ' /ɛK in the Standard Model and beyond

NASA Astrophysics Data System (ADS)

Kitahara, Teppei; Nierste, Ulrich; Tremper, Paul

2016-12-01

The standard analytic solution of the renormalization group (RG) evolution for the Δ S = 1 Wilson coefficients involves several singularities, which complicate analytic solutions. In this paper we derive a singularity-free solution of the next-to-leading order (NLO) RG equations, which greatly facilitates the calculation of ɛ K ' , the measure of direct CP violation in K → ππ decays. Using our new RG evolution and the latest lattice results for the hadronic matrix elements, we calculate the ratio ɛ K ' /ɛ K (with ɛ K quantifying indirect CP violation) in the Standard Model (SM) at NLO to ɛ K ' /ɛ K = (1.06 ± 5.07) × 10- 4, which is 2 .8 σ below the experimental value. We also present the evolution matrix in the high-energy regime for calculations of new physics contributions and derive easy-to-use approximate formulae. We find that the RG amplification of new-physics contributions to Wilson coefficients of the electroweak penguin operators is further enhanced by the NLO corrections: if the new contribution is generated at the scale of 1-10 TeV, the RG evolution between the new-physics scale and the electroweak scale enhances these coefficients by 50-100%. Our solution contains a term of order α EM 2 / α s 2 , which is numerically unimportant for the SM case but should be included in studies of high-scale new-physics.

The contribution of major diagnostic causes to socioeconomic differences in disability retirement.

PubMed

Polvinen, Anu; Laaksonen, Mikko; Gould, Raija; Lahelma, Eero; Martikainen, Pekka

2014-07-01

The aim of this study was twofold: to investigate socioeconomic differences in disability retirement (DR) due to major diseases and find out which diseases contribute most to the overall socioeconomic differences in DR. The data were longitudinal register-based (10% sample of Finns) from Statistics Finland. These data included 258 428 participants aged 35-64 years during the follow-up. The participants were employed or unemployed before the follow-up period 1997-2010. Of all participants, 14 303 men and 13 188 women ended up in DR during the follow-up. Socioeconomic status was categorized into upper- and lower-class non-manual employees, manual workers, and self-employed persons. Cox models were used to estimate hazard ratios for DR due to different diseases. Compared to upper-class non-manual employees, DR was especially high for manual workers whose retirement diagnoses included psychoactive substance use, musculoskeletal diseases (MSD), or cardiovascular diseases. Socioeconomic differences in DR were stronger for younger age groups and men versus women. For females and males, the largest part of the excess DR among manual workers compared to upper-class non-manual employees was due to MSD. In the age group 54-64 years, the contribution of MSD to the total excess was >50% among male manual workers and 75% among female manual workers. Excess DR due to mental disorders concerned only 35-54-year-old manual workers (among 23% men and 26% women). The contribution of MSD to the total excess DR among lower socioeconomic groups was large. Prevention of MSD among manual workers would likely reduce socioeconomic differences in DR.

Texas A&M University in the JET Collaboration - Final Report

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

Fries, Rainer; Ko, Che-Ming

This final report summarizes the work done by PIs at Texas A&M University within the JET Topical Collaboration. The main focus of the group at Texas A&M has been the development and implementation of a hadronization model suitable to calculate hadronization of jet showers in heavy ion collisions event by event. The group successfully developed a hybrid model of parton recombination and remnant string fragmentation including recombination with thermal partons. A code realizing this model was developed and shared with other JET members. In addition, the group at Texas A&M worked on both open and hidden heavy flavor probes. Inmore » particular, they developed a description of heavy flavor hadronization based on recombination, and consistent with in-medium scattering rates of heavy quarks, and suggested the D s meson as a precise probe of the hadronization mechanism. Another noteworthy focus of their work was electromagnetic probes, in particular, dileptons and photons from interactions of jets with the medium. In the soft sector the group has made several contributions to modern topics, e.g. the splitting of elliptic flow between isospin partners and the role of the initial strong gluon fields.« less

Resource and competitive dynamics shape the benefits of public goods cooperation in a plant pathogen

PubMed Central

Platt, Thomas G.; Fuqua, Clay; Bever, James D.

2012-01-01

Cooperative benefits depend on a variety of ecological factors. Many cooperative bacteria increase the population size of their groups by making a public good available. Increased local population size can alleviate the constraints of kin competition on the evolution of cooperation by enhancing the between-group fitness of cooperators. The cooperative pathogenesis of Agrobacterium tumefaciens causes infected plants to exude opines—resources that provide a nearly exclusive source of nutrient for the pathogen. We experimentally demonstrate that opines provide cooperative A. tumefaciens cells a within-group fitness advantage over saprophytic agrobacteria. Our results are congruent with a resource-consumer competition model, which predicts that cooperative, virulent agrobacteria are at a competitive disadvantage when opines are unavailable, but have an advantage when opines are available at sufficient levels. This model also predicts that freeloading agrobacteria that catabolize opines but cannot infect plants competitively displace the cooperative pathogen from all environments. However, we show that these cooperative public goods also promote increased local population size. A model built from the Price Equation shows that this effect on group size can contribute to the persistence of cooperative pathogenesis despite inherent kin competition for the benefits of pathogenesis. PMID:22671559

The role of personal values and basic traits in perceptions of the consequences of immigration: a three-nation study.

PubMed

Vecchione, Michele; Caprara, Gianvittorio; Schoen, Harald; Castro, Josè Luis Gonzàlez; Schwartz, Shalom H

2012-08-01

Using data from Italy, Spain, and Germany (N= 1,569), this study investigated the role of basic values (universalism and security) and basic traits (openness and agreeableness) in predicting perceptions of the consequences of immigration. In line with Schwartz's (1992) theory, we conceptualized security as having two distinct components, one concerned with safety of the self (personal security) and the other with harmony and stability of larger groups and of society (group security). Structural equation modelling revealed that universalism values underlie perceptions that immigration has positive consequences and group security values underlie perceptions that it has negative consequences. Personal security makes no unique, additional contribution. Multi-group analyses revealed that these associations are invariant across the three countries except for a stronger link between universalism and perceptions of the consequences of immigration in Spain. To examine whether values mediate relations of traits to perceptions of immigration, we used the five-factor model. Findings supported a full mediation model. Individuals' traits of openness and agreeableness explained significant variance in security and universalism values. Basic values, in turn, explained perceptions of the consequences of immigration. ©2011 The British Psychological Society.

Trends in inequalities in premature cancer mortality by educational level in Colombia, 1998–2007

PubMed Central

de Vries, Esther; Arroyave, Ivan; Pardo, Constanza; Wiesner, Carolina; Murillo, Raul; Forman, David; Burdorf, Alex; Avendaño, Mauricio

2015-01-01

Background There is paucity of studies on socioeconomic inequalities in cancer mortality in developing countries. We examined trends in inequalities in cancer mortality by educational attainment in Colombia during a period of epidemiological transition and a rapid expansion of health insurance coverage. Methods Population mortality data (1998–2007) were linked to census data to obtain age-standardised cancer mortality rates by educational attainment at ages 25–64 years for stomach, cervical, prostate, lung, colorectal, breast and other cancers. We used Poisson regression to model mortality by educational attainment and estimated the contribution of specific cancers to the Slope Index of Inequality in cancer mortality. Results We observed large educational inequalities in cancer mortality, particularly for cancer of the cervix (RR primary versus tertiary groups=5.75, contributing 51% of cancer inequalities), stomach (RR=2.56 for males, contributing 49% of total cancer inequalities, and RR=1.98 for females, contributing 14% to total cancer inequalities), and lung (RR=1.64 for males contributing 17% of total cancer inequalities, and 1.32 for females contributing 5% to total cancer inequalities). Total cancer mortality rates declined faster among those with higher education, with the exception of mortality from cervical cancer, which declined more rapidly in the lower educational groups. Conclusion There are large socioeconomic inequalities in preventable cancer mortality in Colombia, which underscore the need for intensifying prevention efforts. Reducing cervical cancer through reducing HPV infection, early detection and improved access to treatment of preneoplasic lesions. Reinforcing anti-tobacco measures may be particularly important to curb inequalities in cancer mortality. PMID:25492898

Effect of sodium aescinate treatment on PCOS rat model with insulin resistance.

PubMed

Chen, L; Hu, L M; Wang, Y F; Yang, H Y; Huang, X Y; Zhou, W; Sun, H X

2017-01-01

Recent studies indicated that insulin resistance may contribute to the pathogenesis of polycystic ovary syndrome (PCOS); however, the specific mechanism is still unclear. To investigate the effect of sodium aescinate (SA) on PCOS-IR rat models. Sixty rats were randomly divided into the five groups: un-treated rats (n = 12), PCOS-IR group (n = 12), PCOS-IR group plus 50 mg/kg SA (n = 12), PCOS-IR group plus 10 mg/kg SA (n = 12), PCOS-IR group plus 150 mg/kg metformin (n = 12). On day 21, rats were sacrificed, and H(and)E staining was performed for histopathologic examination of the ovaries; moreover, the serum level of follicle-stimulating hormone (FSH), testosterone, and luteotropic hormone (LH) were measured, and the expression as well as phosphorylation of PI3K, Akt and Gsk-3β were examined using western blot assay. High dosage of SA treatment improved the morphological features of the ovaries in PCOS rats, and also induced significant decrease in serum expression of testosterone and LH/FSH ratio and significant decrease in the expression of p-PI3K, p-Akt and p-Gsk-3β. Our results demonstrated that SA treatment could alleviate the symptom of PCOS in rat model through regulating the PI3K/Akt/GSK3-β pathway (Fig. 4, Ref. 22).

Comparison of the stability of various internal fixators used in the treatment of osteochondritis dissecans--a mechanical model.

PubMed

Morelli, Moreno; Poitras, Philippe; Grimes, Valentine; Backman, David; Dervin, Geoffrey

2007-04-01

The purpose of this study was to determine what characteristics of fixation devices used in the treatment of osteochondritis dissecans (OCD) contribute to improved stability to resist shear loading. An OCD model was designed using rigid polyurethane foam. Each specimen consisted of two components, an osteochondral fragment and a corresponding defect. A total of 40 specimens were prepared and assigned to one of four groups: control (no extrinsic stabilizer); two 2-mm-diameter Kirschner wires (K-wires), 40 mm in length; one threaded washer and a 28-mm screw; and one threaded washer and a 38 mm screw. Each specimen was mounted onto an Iosipescu shear test fixture and subjected to shear loads at a pseudo-static displacement rate of 0.075 mm/s. All groups demonstrated some stability; controls were significantly less stable than all other groups. The group with the threaded washer and 38-mm screw demonstrated the greatest stability (p < 0.001), and no difference was noted between the K-wire and 28-mm screw groups. These results suggest that, in this OCD model, friction conferred some intrinsic stability to resist loads in shear. However, stability was improved with the use of long implants that compressed the fragments together.

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

PubMed Central

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

2011-01-01

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

Structure-Activity Correlations for β-Phenethylamines at Human Trace Amine Receptor 1

PubMed Central

Lewin, Anita H.; Navarro, Hernán A.; Mascarella, S. Wayne

2008-01-01

A cell line in which RD-HGA16 cells were stably transfected with the hTAAR 1 receptor was created and utilized to carry out a systematic evaluation of a series of β-phenethylamines. Fair agreement was observed with data obtained for aryl and ethylene chain substituted analogs in an AV12-664 cell line in which hemagglutinin-tagged hTAAR 1 was stably co-expressed with rat Gαs. Analogs with multiple substituents as well as analogs with bulky groups were found to be partial agonists. Analogs in which the primary amino group was converted to a secondary or a tertiary amino group by N-methylation were also partial agonists. Comparative Molecular Field Analysis (CoMFA) using the potency data yielded a regression coefficient r2 of 0.824. The steric field contribution to the model was 61% with the balance (39%) contributed by the electrostatic field. The collective results suggest that increasing steric bulk at both the amino nitrogen, particularly by N-dimethylation, and at the 4-position of the aromatic ring, leads to low efficacy ligands. PMID:18602830

Similarity-transformed chiral NN + 3N interactions for the ab initio description of 12C and 16O.

PubMed

Roth, Robert; Langhammer, Joachim; Calci, Angelo; Binder, Sven; Navrátil, Petr

2011-08-12

We present first ab initio no-core shell model (NCSM) calculations using similarity renormalization group (SRG) transformed chiral two-nucleon (NN) plus three-nucleon (3N) interactions for nuclei throughout the p-shell, particularly (12)C and (16)O. By introducing an adaptive importance truncation for the NCSM model space and an efficient JT-coupling scheme for the 3N matrix elements, we are able to surpass previous NCSM studies including 3N interactions. We present ground and excited states in (12)C and (16)O for model spaces up to N(max) = 12 including full 3N interactions. We analyze the contributions of induced and initial 3N interactions and probe induced 4N terms through the sensitivity of the energies on the SRG flow parameter. Unlike for light p-shell nuclei, SRG-induced 4N contributions originating from the long-range two-pion terms of the chiral 3N interaction are sizable in (12)C and (16)O.

Role of opioid receptors in the reinstatement of opioid-seeking behavior: an overview.

PubMed

Fattore, Liana; Fadda, Paola; Antinori, Silvia; Fratta, Walter

2015-01-01

Opioid abuse in humans is characterized by discontinuous periods of drug use and abstinence. With time, the probability of falling into renewed drug consumption becomes particularly high and constitutes a considerable problem in the management of heroin addicts. The major problem in the treatment of opioid dependence still remains the occurrence of relapse, to which stressful life events, renewed use of heroin, and exposure to drug-associated environmental cues are all positively correlated. To study the neurobiology of relapse, many research groups currently use the reinstatement animal model, which greatly contributed to disentangle the mechanisms underlying relapse to drug-seeking in laboratory animals. The use of this model is becoming increasingly popular worldwide, and new versions have been recently developed to better appreciate the differential contribution of each opioid receptor subtype to the relapse phenomenon. In this chapter we review the state of the art of our knowledge on the specific role of the opioid receptors as unrevealed by the reinstatement animal model of opioid-seeking behavior.

Modeling ready biodegradability of fragrance materials.

PubMed

Ceriani, Lidia; Papa, Ester; Kovarich, Simona; Boethling, Robert; Gramatica, Paola

2015-06-01

In the present study, quantitative structure activity relationships were developed for predicting ready biodegradability of approximately 200 heterogeneous fragrance materials. Two classification methods, classification and regression tree (CART) and k-nearest neighbors (kNN), were applied to perform the modeling. The models were validated with multiple external prediction sets, and the structural applicability domain was verified by the leverage approach. The best models had good sensitivity (internal ≥80%; external ≥68%), specificity (internal ≥80%; external 73%), and overall accuracy (≥75%). Results from the comparison with BIOWIN global models, based on group contribution method, show that specific models developed in the present study perform better in prediction than BIOWIN6, in particular for the correct classification of not readily biodegradable fragrance materials. © 2015 SETAC.

[Organizational and management companies models].

PubMed

Tomei, G; Tomei, F; Fiaschetti, M; De Sio, S; Tria, M; Schifano, M P; Monti, C; Tasciotti, Z; Panfili, T; Caciari, A; Sancini, A

2010-01-01

With the legislative decree 81/08 and s.m.i. it's explicitly defined a model of management and corporate organization that can contribute to prevent security risks in work environments. The realization of the model is not obligatory, but desirable because the result of its implementation is a decrease of company's risks and costs for safety. Our study group has developed the structure of an organizational and management model for corporate safety and the tools necessary for its realization. The realization of a model is structured in various phases: initial exam, safety policy, planification, implementation, monitoring, system retest and improvement. Such a model, in continuous evolution, is based on the responsibilities of the different corporate figures through an accurate analysis of the measured risks and the measures adopted.

Effects of High-Intensity Training on Anaerobic and Aerobic Contributions to Total Energy Release During Repeated Supramaximal Exercise in Obese Adults.

PubMed

Jabbour, Georges; Iancu, Horia-Daniel; Paulin, Anne

Studying relative anaerobic and aerobic metabolism contributions to total energy release during exercise may be valuable in understanding exercise energetic demands and the energetic adaptations that occur in response to acute or chronic exercise in obese adults. The aim of the present study is to evaluate the effects of 6 weeks of high-intensity training (HIT) on relative anaerobic and aerobic contributions to total energy release and on peak power output during repeated supramaximal cycling exercises (SCE) in obese adults. Twenty-four obese adults (body mass index = ± 33 kg.m -2 ) were randomized into a control group ( n  = 12) and an HIT group ( n  = 12). Accumulated oxygen deficits (ml.min -1 ) and anaerobic and aerobic contributions (%) were measured in all groups before and after training via repeated SCE. In addition, the peak power output performed during SCE was determined using the force-velocity test. Before HIT, anaerobic contributions to repeated SCE did not differ between the groups and decreased significantly during the third and fourth repetitions. After HIT, anaerobic contributions increased significantly in the HIT group (+11 %, p  < 0.01) and were significantly higher than those of the control group ( p  < 0.01). Moreover, the peak power obtained during SCE increased significantly in the HIT group (+110 W.kg -1 , p  < 0.01) and correlated positively with increases in anaerobic contributions ( r  = 0.9, p  < 0.01). In obese adults, HIT increased anaerobic contributions to energy release which were associated with peak power enhancement in response to repeated SCE. Consequently, HIT may be an appropriate approach for improving energy contributions and muscle power among obese adults.

In-group defense, out-group aggression, and coordination failures in intergroup conflict

PubMed Central

De Dreu, Carsten K. W.; Méder, Zsombor; Giffin, Michael; Prochazkova, Eliska; Krikeb, Jonathan

2016-01-01

Intergroup conflict persists when and because individuals make costly contributions to their group’s fighting capacity, but how groups organize contributions into effective collective action remains poorly understood. Here we distinguish between contributions aimed at subordinating out-groups (out-group aggression) from those aimed at defending the in-group against possible out-group aggression (in-group defense). We conducted two experiments in which three-person aggressor groups confronted three-person defender groups in a multiround contest game (n = 276; 92 aggressor–defender contests). Individuals received an endowment from which they could contribute to their group’s fighting capacity. Contributions were always wasted, but when the aggressor group’s fighting capacity exceeded that of the defender group, the aggressor group acquired the defender group’s remaining resources (otherwise, individuals on both sides were left with the remainders of their endowment). In-group defense appeared stronger and better coordinated than out-group aggression, and defender groups survived roughly 70% of the attacks. This low success rate for aggressor groups mirrored that of group-hunting predators such as wolves and chimpanzees (n = 1,382 cases), hostile takeovers in industry (n = 1,637 cases), and interstate conflicts (n = 2,586). Furthermore, whereas peer punishment increased out-group aggression more than in-group defense without affecting success rates (Exp. 1), sequential (vs. simultaneous) decision-making increased coordination of collective action for out-group aggression, doubling the aggressor’s success rate (Exp. 2). The relatively high success rate of in-group defense suggests evolutionary and cultural pressures may have favored capacities for cooperation and coordination when the group goal is to defend, rather than to expand, dominate, and exploit. PMID:27601640

Implementation and evaluation of PM2.5 source contribution ...

EPA Pesticide Factsheets

Source culpability assessments are useful for developing effective emissions control programs. The Integrated Source Apportionment Method (ISAM) has been implemented in the Community Multiscale Air Quality (CMAQ) model to track contributions from source groups and regions to ambient levels and deposited amounts of primary and secondary inorganic PM2.5. Confidence in this approach is established by comparing ISAM source contribution estimates to emissions zero-out simulations recognizing that these approaches are not always expected to provide the same answer. The comparisons are expected to be most similar for more linear processes such as those involving primary emissions of PM2.5 and most different for non-linear systems like ammonium nitrate formation. Primarily emitted PM2.5 (e.g. elemental carbon), sulfur dioxide, ammonia, and nitrogen oxide contribution estimates compare well to zero-out estimates for ambient concentration and deposition. PM2.5 sulfate ion relationships are strong, but nonlinearity is evident and shown to be related to aqueous phase oxidation reactions in the host model. ISAM and zero-out contribution estimates are less strongly related for PM2.5 ammonium nitrate, resulting from instances of non-linear chemistry and negative responses (increases in PM2.5 due to decreases in emissions). ISAM is demonstrated in the context of an annual simulation tracking well characterized emissions source sectors and boundary conditions shows source contri

Coarse Graining to Investigate Membrane Induced Peptide Folding of Anticancer Peptides

NASA Astrophysics Data System (ADS)

Ganesan, Sai; Xu, Hongcheng; Matysiak, Silvina

Information about membrane induced peptide folding mechanisms using all-atom molecular dynamics simulations is a challenge due to time and length scale issues.We recently developed a low resolution Water Explicit Polarizable PROtein coarse-grained Model by adding oppositely charged dummy particles inside protein backbone beads.These two dummy particles represent a fluctuating dipole,thus introducing structural polarization into the coarse-grained model.With this model,we were able to achieve significant α- β secondary structure content de novo,without any added bias.We extended the model to zwitterionic and anionic lipids,by adding oppositely charged dummy particles inside polar beads, to capture the ability of the head group region to form hydrogen bonds.We use zwitterionic POPC and anionic POPS as our model lipids, and a cationic anticancer peptide,SVS1,as our model peptide.We have characterized the driving forces for SVS1 folding on lipid bilayers with varying anionic and zwitterionic lipid compositions.Based on our results, dipolar interactions between peptide backbone and lipid head groups contribute to stabilize folded conformations.Cooperativity in folding is induced by both intra peptide and membrane-peptide interaction.

Restoration of dimensional reduction in the random-field Ising model at five dimensions

NASA Astrophysics Data System (ADS)

Fytas, Nikolaos G.; Martín-Mayor, Víctor; Picco, Marco; Sourlas, Nicolas

2017-04-01

The random-field Ising model is one of the few disordered systems where the perturbative renormalization group can be carried out to all orders of perturbation theory. This analysis predicts dimensional reduction, i.e., that the critical properties of the random-field Ising model in D dimensions are identical to those of the pure Ising ferromagnet in D -2 dimensions. It is well known that dimensional reduction is not true in three dimensions, thus invalidating the perturbative renormalization group prediction. Here, we report high-precision numerical simulations of the 5D random-field Ising model at zero temperature. We illustrate universality by comparing different probability distributions for the random fields. We compute all the relevant critical exponents (including the critical slowing down exponent for the ground-state finding algorithm), as well as several other renormalization-group invariants. The estimated values of the critical exponents of the 5D random-field Ising model are statistically compatible to those of the pure 3D Ising ferromagnet. These results support the restoration of dimensional reduction at D =5 . We thus conclude that the failure of the perturbative renormalization group is a low-dimensional phenomenon. We close our contribution by comparing universal quantities for the random-field problem at dimensions 3 ≤D <6 to their values in the pure Ising model at D -2 dimensions, and we provide a clear verification of the Rushbrooke equality at all studied dimensions.

Restoration of dimensional reduction in the random-field Ising model at five dimensions.

PubMed

Fytas, Nikolaos G; Martín-Mayor, Víctor; Picco, Marco; Sourlas, Nicolas

2017-04-01

The random-field Ising model is one of the few disordered systems where the perturbative renormalization group can be carried out to all orders of perturbation theory. This analysis predicts dimensional reduction, i.e., that the critical properties of the random-field Ising model in D dimensions are identical to those of the pure Ising ferromagnet in D-2 dimensions. It is well known that dimensional reduction is not true in three dimensions, thus invalidating the perturbative renormalization group prediction. Here, we report high-precision numerical simulations of the 5D random-field Ising model at zero temperature. We illustrate universality by comparing different probability distributions for the random fields. We compute all the relevant critical exponents (including the critical slowing down exponent for the ground-state finding algorithm), as well as several other renormalization-group invariants. The estimated values of the critical exponents of the 5D random-field Ising model are statistically compatible to those of the pure 3D Ising ferromagnet. These results support the restoration of dimensional reduction at D=5. We thus conclude that the failure of the perturbative renormalization group is a low-dimensional phenomenon. We close our contribution by comparing universal quantities for the random-field problem at dimensions 3≤D<6 to their values in the pure Ising model at D-2 dimensions, and we provide a clear verification of the Rushbrooke equality at all studied dimensions.

Developing a model for effective leadership in healthcare: a concept mapping approach.

PubMed

Hargett, Charles William; Doty, Joseph P; Hauck, Jennifer N; Webb, Allison Mb; Cook, Steven H; Tsipis, Nicholas E; Neumann, Julie A; Andolsek, Kathryn M; Taylor, Dean C

2017-01-01

Despite increasing awareness of the importance of leadership in healthcare, our understanding of the competencies of effective leadership remains limited. We used a concept mapping approach (a blend of qualitative and quantitative analysis of group processes to produce a visual composite of the group's ideas) to identify stakeholders' mental model of effective healthcare leadership, clarifying the underlying structure and importance of leadership competencies. Literature review, focus groups, and consensus meetings were used to derive a representative set of healthcare leadership competency statements. Study participants subsequently sorted and rank-ordered these statements based on their perceived importance in contributing to effective healthcare leadership in real-world settings. Hierarchical cluster analysis of individual sortings was used to develop a coherent model of effective leadership in healthcare. A diverse group of 92 faculty and trainees individually rank-sorted 33 leadership competency statements. The highest rated statements were "Acting with Personal Integrity", "Communicating Effectively", "Acting with Professional Ethical Values", "Pursuing Excellence", "Building and Maintaining Relationships", and "Thinking Critically". Combining the results from hierarchical cluster analysis with our qualitative data led to a healthcare leadership model based on the core principle of Patient Centeredness and the core competencies of Integrity, Teamwork, Critical Thinking, Emotional Intelligence, and Selfless Service. Using a mixed qualitative-quantitative approach, we developed a graphical representation of a shared leadership model derived in the healthcare setting. This model may enhance learning, teaching, and patient care in this important area, as well as guide future research.

Cognitive Factors Contributing to Spelling Performance in Children with Prenatal Alcohol Exposure

PubMed Central

Glass, Leila; Graham, Diana M.; Akshoomoff, Natacha; Mattson, Sarah N.

2015-01-01

Objective Heavy prenatal alcohol exposure is associated with impaired school functioning. Spelling performance has not been comprehensively evaluated. We examined whether children with heavy prenatal alcohol exposure demonstrate deficits in spelling and related abilities, including reading, and tested whether there are unique underlying mechanisms for observed deficits in this population. Method Ninety-six school-age children comprised two groups: children with heavy prenatal alcohol exposure (AE, n=49) and control children (CON, n=47). Children completed select subtests from the WIAT-II and NEPSY-II. Group differences and relations between spelling and theoretically-related cognitive variables were evaluated using MANOVA and Pearson correlations. Hierarchical regression analyses were utilized to assess contributions of group membership and cognitive variables to spelling performance. The specificity of these deficits and underlying mechanisms was tested by examining the relations between reading ability, group membership, and cognitive variables. Results Groups differed significantly on all variables. Group membership and phonological processing significantly contributed to spelling performance. In addition, a significant group*working memory interaction revealed that working memory independently contributed significantly to spelling only for the AE group. All cognitive variables contributed to reading across groups and a group*working memory interaction revealed that working memory contributed independently to reading only for alcohol-exposed children. Conclusion Alcohol-exposed children demonstrated a unique pattern of spelling deficits. The relation of working memory to spelling and reading was specific to the AE group, suggesting that if prenatal alcohol exposure is known or suspected, working memory ability should be considered in the development and implementation of explicit instruction. PMID:25643217

Unusual specific heat of almost dry L-cysteine and L-cystine amino acids.

PubMed

Ishikawa, M S; Lima, T A; Ferreira, F F; Martinho, H S

2015-03-01

A detailed quantitative analysis of the specific heat in the 0.5- to 200-K temperature range for almost dry L-cysteine and its dimer, L-cystine, amino acids is presented. We report the occurrence of a sharp first-order transition at ∼76 K for L-cysteine associated with the thiol group ordering which was successfully modeled with the two-dimensional Ising model. We demonstrated that quantum rotors, two-level systems (TLS), Einstein oscillators, and acoustic phonons (the Debye model) are essential ingredients to correctly describe the overall experimental data. Our analysis pointed out the absence of the TLS contribution to the low temperature specific heat of L-cysteine. This result was similar to that found in other noncrystalline amorphous materials, e.g., amorphous silicon, low density amorphous water, and ultrastable glasses. L-cystine presented an unusual nonlinear acoustic dispersion relation ω(q)=vq0.95 and a Maxwell-Boltzmann-type distribution of tunneling barriers. The presence of Einstein oscillators with ΘE∼70 K was common in both systems and adequately modeled the boson peak contributions.

Quantifying inter- and intra-population niche variability using hierarchical bayesian stable isotope mixing models.

PubMed

Semmens, Brice X; Ward, Eric J; Moore, Jonathan W; Darimont, Chris T

2009-07-09

Variability in resource use defines the width of a trophic niche occupied by a population. Intra-population variability in resource use may occur across hierarchical levels of population structure from individuals to subpopulations. Understanding how levels of population organization contribute to population niche width is critical to ecology and evolution. Here we describe a hierarchical stable isotope mixing model that can simultaneously estimate both the prey composition of a consumer diet and the diet variability among individuals and across levels of population organization. By explicitly estimating variance components for multiple scales, the model can deconstruct the niche width of a consumer population into relevant levels of population structure. We apply this new approach to stable isotope data from a population of gray wolves from coastal British Columbia, and show support for extensive intra-population niche variability among individuals, social groups, and geographically isolated subpopulations. The analytic method we describe improves mixing models by accounting for diet variability, and improves isotope niche width analysis by quantitatively assessing the contribution of levels of organization to the niche width of a population.

Misbehaving macrophages in the pathogenesis of psoriasis

PubMed Central

Clark, Rachael A.; Kupper, Thomas S.

2006-01-01

Psoriasis is a chronic inflammatory skin disease unique to humans. In this issue of the JCI, 2 studies of very different mouse models of psoriasis both report that macrophages play a key role in inducing psoriasis-like skin disease. Psoriasis is clearly a polygenic, inherited disease of uncontrolled cutaneous inflammation. The debate that currently rages in the field is whether psoriasis is a disease of autoreactive T cells or whether it reflects an intrinsic defect within the skin — or both. However, these questions have proven difficult to dissect using molecular genetic tools. In the current studies, the authors have used 2 different animal models to address the role of macrophages in disease pathogenesis: Wang et al. use a mouse model in which inflammation is T cell dependent, whereas the model used by Stratis et al. is T cell independent (see the related articles beginning on pages 2105 and 2094, respectively). Strikingly, both groups report an important contribution by macrophages, implying that macrophages can contribute to both epithelial-based and T cell–mediated pathways of inflammation. PMID:16886055

On the ability of trehalose to offset the denaturing activity of urea

NASA Astrophysics Data System (ADS)

Graziano, Giuseppe

2013-01-01

Experimental and computational studies indicate that trehalose offsets the denaturing activity of urea. According to a statistical thermodynamic model, the fundamental stabilizing contribution arises from the difference in the work to create a cavity suitable to host the D-state and the N-state, respectively. The magnitude of this solvent-excluded volume effect increases with aqueous solution density. Trehalose and urea addition to water leads to a density increase, that translates in an increase in the magnitude of the solvent-excluded volume effect which is so large to overwhelm the destabilizing contribution arising from the energetic attractions of urea with protein surface groups.

Women in mathematics, science, and engineering college majors: A model predicting career aspirations based on ability, self-efficacy, role model influence, and role conflict

NASA Astrophysics Data System (ADS)

Nauta, Margaret Mary

1997-09-01

This study investigated a model of predictors of career aspirations among two groups of women: students in mathematics, physical science, and engineering majors and students in biological science majors. Based on theories of women's career development and social-cognitive theories, it was hypothesized that ability, self-efficacy, positivity of role model influence, and role conflict would influence the career aspirations of these women. It was further hypothesized that the students' year in school would contribute to this model as a predictor variable. Five hundred forty-six students (representing a 71% response rate) from Iowa State University were surveyed by mail to evaluate the fit of this model. The structural equation modeling procedure revealed that the career aspirations of the two groups of women were directly predicted by self-efficacy and role conflict and indirectly predicted by year in school, academic ability, and positivity of role model influence. The model for this combined group of students represented a good overall fit, explaining 94% of the covariation among the measured variables. When the two groups of students were compared, identical models for women in the two groups revealed different relationships among the variables. In contrast to the women in math, physical science, and engineering majors, the relationships between ability and self-efficacy and between positivity of role model influence and self-efficacy were significantly lower in magnitude for women in the biological sciences group. In addition to providing a parsimonious model for conceptualizing the experiences of women in traditionally male fields, this study's findings have implications for increasing the number of women who aspire to advanced careers in these occupations. Primarily, this study suggests that interventions designed to increase the degree to which students are influenced positively by role models may increase their self-efficacy expectations and may decrease the amount of conflict they perceive between the roles of worker and spouse or parent. In turn, increasing self-efficacy and decreasing role conflict may increase the degree to which students aspire to leadership and top-level careers within mathematics, the physical sciences, and engineering.

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

Flores-Tlalpa, A.; Novales-Sanchez, H.; Toscano, J. J.

The one-loop contribution of the excited Kaluza-Klein (KK) modes of the SU{sub L}(2) gauge group on the off-shell W{sup -}W{sup +}{gamma} and W{sup -}W{sup +}Z vertices is calculated in the context of a pure Yang-Mills theory in five dimensions and its phenomenological implications discussed. The use of a gauge-fixing procedure for the excited KK modes that is covariant under the standard gauge transformations of the SU{sub L}(2) group is stressed. A gauge-fixing term and the Faddeev-Popov ghost sector for the KK gauge modes that are separately invariant under the standard gauge transformations of SU{sub L}(2) are presented. It is shownmore » that the one-loop contributions of the KK modes to the off-shell W{sup -}W{sup +}{gamma} and W{sup -}W{sup +}Z vertices are free of ultraviolet divergences and well-behaved at high energies. It is found that for a size of the fifth dimension of R{sup -1{approx}}1 TeV, the one-loop contribution of the KK modes to these vertices is about 1 order of magnitude lower than the corresponding standard model radiative correction. This contribution is similar to the one estimated for new gauge bosons contributions in other contexts. Tree-level effects on these vertices induced by operators of higher canonical dimension are also investigated. It is found that these effects are lower than those generated at the one-loop order by the KK gauge modes.« less

Context Matters: Contribution of Specific DNA Adducts to the Genotoxic Properties of the Tobacco-Specific Nitrosamine NNK.

PubMed

Peterson, Lisa A

2017-01-17

The tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is a potent pulmonary carcinogen in laboratory animals. It is classified as a Group 1 human carcinogen by the International Agency for Cancer Research. NNK is bioactivated upon cytochrome P450 catalyzed hydroxylation of the carbon atoms adjacent to the nitrosamino group to both methylating and pyridyloxobutylating agents. Both pathways generate a spectrum of DNA damage that contributes to the overall mutagenic and toxic properties of this compound. NNK is also reduced to form 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), which is also carcinogenic. Like NNK, NNAL requires metabolic activation to DNA alkylating agents. Methyl hydroxylation of NNAL generates pyridylhydroxybutyl DNA adducts, and methylene hydroxylation leads to DNA methyl adducts. The consequence of this complex metabolism is that NNK generates a vast spectrum of DNA damage, any form of which can contribute to the overall carcinogenic properties of this potent pulmonary carcinogen. This Perspective reviews the chemistry and genotoxic properties of the collection of DNA adducts formed from NNK. In addition, it provides evidence that multiple adducts contribute to the overall carcinogenic properties of this chemical. The adduct that contributes to the genotoxic effects of NNK depends on the context, such as the relative amounts of each DNA alkylating pathway occurring in the model system, the levels and genetic variants of key repair enzymes, and the gene targeted for mutation.

Repeated sense of hunger leads to the development of visceral obesity and metabolic syndrome in a mouse model.

PubMed

Han, Jong-Min; Kim, Hyeong-Geug; Lee, Jin-Seok; Choi, Min-Kyung; Kim, Young-Ae; Son, Chang-Gue

2014-01-01

Obesity-related disorders, especially metabolic syndrome, contribute to 2.8 million deaths each year worldwide, with significantly increasing morbidity. Eating at regular times and proper food quantity are crucial for maintaining a healthy status. However, many people in developed countries do not follow a regular eating schedule due to a busy lifestyle. Herein, we show that a repeated sense of hunger leads to a high risk of developing visceral obesity and metabolic syndrome in a mouse model (both 3-week and 6-week-old age, 10 mice in each group). The ad libitum (AL) group (normal eating pattern) and the food restriction (FR) group (alternate-day partially food restriction by given only 1/3 of average amount) were compared after 8-week experimental period. The total food consumption in the FR group was lower than in the AL group, however, the FR group showed a metabolic syndrome-like condition with significant fat accumulation in adipose tissues. Consequently, the repeated sense of hunger induced the typical characteristics of metabolic syndrome in an animal model; a distinct visceral obesity, hyperlipidemia, hyperglycemia and hepatic steatosis. Furthermore, we found that specifically leptin, a major metabolic hormone, played a major role in the development of these pathological disorders. Our study indicated the importance of regular eating habits besides controlling calorie intake.

The developmental dynamics of gait maturation with a focus on spatiotemporal measures.

PubMed

Kraan, C M; Tan, A H J; Cornish, K M

2017-01-01

Gait analysis is recognised as a powerful clinical tool for studying relationships between motor control and brain function. By drawing on the literature investigating gait in individuals with neurological disorders, this review provides insight into the neural processes that contribute to and regulate specific spatiotemporal sub-components of gait and how they may mature across early to late childhood. This review also discusses the roles of changing anthropomorphic characteristics, and maturing sensory and higher-order cognitive processes in differentiating the developmental trajectories of the sub-components of gait. Importantly, although studies have shown that cognitive-gait interference is larger in children compared to adults, the contributing neurocognitive mechanisms may vary across age groups who have different types of attentional or cognitive vulnerabilities. These findings have implications for current models of gait maturation by highlighting the need for a dynamic model that focuses on the integration of various factors that contribute to gait though experience and practice. This is essential to elucidating why gait and other motor deficits are often contiguous with cognitive neurodevelopmental disorders. Copyright © 2016. Published by Elsevier B.V.

Genetic modulation of the iris transillumination defect: a systems genetics analysis using the expanded family of BXD glaucoma strains

PubMed Central

Swaminathan, Shankar; Lu, Hong; Williams, Robert W; Lu, Lu; Jablonski, Monica M

2013-01-01

We investigated the contributions of Tyrp1 and Gpnmb to the iris transillumination defect (TID) in five age cohorts of BXD mice. Using systems genetics, we also evaluated the role of other known pigmentation genes (PGs). Mapping studies indicate that Tyrp1 contributes to the phenotype at all ages, yet the TID maps to Gpnmb only in the oldest cohort. Composite interval mapping reveals secondary loci viz. Oca2, Myo5a, Prkcz, and Zbtb20 that modulate the phenotype in the age groups up to 10–13 months. The contributions of Tyrp1 and Gpnmb were highly significant in all age cohorts. Moreover, in young mice, all six gene candidates had substantial interactions in our model. Our model accounted for 71–88% of the explained variance of the TID phenotype across the age bins. These results demonstrate that along with Tyrp1 and Gpnmb, Oca2, Myo5a, Prkcz, and Zbtb20 modulate the TID in an age-dependent manner. PMID:23582180

Non-Alzheimer's contributions to dementia and cognitive resilience in The 90+ Study.

PubMed

Robinson, John L; Corrada, Maria M; Kovacs, Gabor G; Dominique, Myrna; Caswell, Carrie; Xie, Sharon X; Lee, Virginia M-Y; Kawas, Claudia H; Trojanowski, John Q

2018-06-18

The diagnosis of Alzheimer's disease (AD) in the oldest-old is complicated by the increasing prevalence of age-related neurofibrillary tangles, plaques and non-AD pathologies such as cerebrovascular disease (CVD), hippocampal sclerosis (HS), aging-related tau astrogliopathy (ARTAG), as well as TDP-43 and Lewy pathology. The contribution of these non-AD pathologies to dementia and cognitive resilience is unclear. We assessed the level of AD neuropathologic change (ADNPC) and non-AD pathology in 185 participants enrolled in The 90+ Study with available cognitive assessments and brain tissue. Logistic regression models-adjusting for age, sex and education-determined the association between each pathology and dementia or between subgroups. 53% had dementia, primarily AD or mixed AD; 23% had cognitive impairment without dementia (CIND); 23% were not impaired. Both AD and non-AD pathology was prevalent. 100% had tangles, 81% had plaques, and both tangles and plaques associated with dementia. ARTAG distributed across limbic (70%), brainstem (39%) and cortical regions (24%). 49% had possible CVD and 26% had definite CVD, while HS was noted in 15%. Cortical ARTAG, CVD and HS were each associated with dementia, but limbic and brainstem ARTAGs were not. TDP-43 and Lewy pathologies were found in 36 and 17% and both associated with dementia. No pathology distinguished CIND and the not impaired. By NIA-AA criteria and dementia status, the cohort was subdivided into four groups: those with minimal ADNPC included the not dementia (ND) and Not AD dementia groups; and those with significant ADNPC included the Resilient without dementia and AD dementia groups. Compared to the ND group, the Not AD dementia group had more HS, cortical ARTAG, TDP-43, and Lewy pathology. Compared to the AD dementia group, the Resilient group had less CVD, no HS and less cortical ARTAG, TDP-43 and Lewy pathology. Our findings imply that reductions in non-AD pathologies including CVD contribute to cognitive resilience in the oldest-old.

Source contributions to United States ozone and particulate matter over five decades from 1970 to 2020

NASA Astrophysics Data System (ADS)

Nopmongcol, Uarporn; Alvarez, Yesica; Jung, Jaegun; Grant, John; Kumar, Naresh; Yarwood, Greg

2017-10-01

Evaluating long-term air quality trends can demonstrate effectiveness of control strategies and guide future air quality management planning. Observations have shown that ozone (O3) and fine particulate matter (PM2.5) in the US have declined since as early as 1980 in some areas. But observation trends alone cannot separate effects of changes in local and global emissions to US air quality which are important to air quality planners. This study uses a regional model (CAMx) nested within a global model (GEOS-Chem) to characterize regional changes in O3 and PM2.5 due to the intercontinental transport and local/regional emissions representing six modeling years within five decades (1970-2020). We use the CAMx Source Apportionment Technology (OSAT/PSAT) to estimate contributions from 6 source sectors in 7 source regions plus 6 other groups for a total of 48 tagged contributions. On-road mobile sources consistently make the largest U.S. anthropogenic emissions contribution to O3 in all cities examined even though they decline substantially from 1970 to 2005 and also from 2005 to 2020. Off-road mobile source contributions increase from 1970 to 2005 and then decrease after 2005 in all of the cities. The boundary conditions, mostly from intercontinental transport, contribute more than 20 ppb to high maximum daily 8-h average (MDA8) O3 for all six years. We found that lowering NOx emissions raises O3 formation efficiency (OFE) across all emission categories which will limit potential O3 benefits of local NOx strategies in the near future. PM2.5 benefited from adoption of control devices between 1970 and 1980 and has continued to decline through 2005 and expected to decline further by 2020. Area sources such as residential, commercial and fugitive dust emissions stand out as making large contributions to PM2.5 that are not declining. Inter-regional transport is less important in 2020 than 1990 for both pollutants.

Exploratory multinomial logit model-based driver injury severity analyses for teenage and adult drivers in intersection-related crashes.

PubMed

Wu, Qiong; Zhang, Guohui; Ci, Yusheng; Wu, Lina; Tarefder, Rafiqul A; Alcántara, Adélamar Dely

2016-05-18

Teenage drivers are more likely to be involved in severely incapacitating and fatal crashes compared to adult drivers. Moreover, because two thirds of urban vehicle miles traveled are on signal-controlled roadways, significant research efforts are needed to investigate intersection-related teenage driver injury severities and their contributing factors in terms of driver behavior, vehicle-infrastructure interactions, environmental characteristics, roadway geometric features, and traffic compositions. Therefore, this study aims to explore the characteristic differences between teenage and adult drivers in intersection-related crashes, identify the significant contributing attributes, and analyze their impacts on driver injury severities. Using crash data collected in New Mexico from 2010 to 2011, 2 multinomial logit regression models were developed to analyze injury severities for teenage and adult drivers, respectively. Elasticity analyses and transferability tests were conducted to better understand the quantitative impacts of these factors and the teenage driver injury severity model's generality. The results showed that although many of the same contributing factors were found to be significant in the both teenage and adult driver models, certain different attributes must be distinguished to specifically develop effective safety solutions for the 2 driver groups. The research findings are helpful to better understand teenage crash uniqueness and develop cost-effective solutions to reduce intersection-related teenage injury severities and facilitate driver injury mitigation research.

Universal seesaw and 0νββ in new 3331 left-right symmetric model

NASA Astrophysics Data System (ADS)

Borah, Debasish; Patra, Sudhanwa

2017-08-01

We consider a class of left-right symmetric model with enlarged gauge group SU(3)c × SU(3)L × SU(3)R × U(1)X without having scalar bitriplet. In the absence of scalar bitriplet, there is no Dirac mass term for fermions including usual quarks and leptons. We introduce new isosinglet vector-like fermions so that all the fermions get their masses through a universal seesaw mechanism. We extend our discussion to neutrino mass and its implications in neutrinoless double beta decay (0 νββ). We show that for TeV scale SU(3)R gauge bosons, the heavy-light neutrino mixing contributes dominantly to 0 νββ that can be observed at ongoing experiments. The new physics contributions arising from purely left-handed currents via exchange of keV scale right-handed neutrinos and the so called mixed helicity λ-diagram can saturate the KamLANDZen bound. We show that the right handed neutrinos in this model can have mass in the sub keV range and can be long lived compared to the age of the Universe. The contributions of these right handed neutrinos to flavour physics observables like μ → eγ and muon g - 2 is also discussed. Towards the end we also comment on different possible symmetry breaking patterns of this enlarged gauge symmetry to that of the standard model.

Beijing ambient particle exposure accelerates atherosclerosis in ApoE knockout mice.

PubMed

Chen, Tian; Jia, Guang; Wei, Yongjie; Li, Jiucun

2013-11-25

Air pollution is associated with significant adverse health effects including increased cardiovascular morbidity and mortality. However research on the cardiovascular effect of "real-world" exposure to ambient particulate matter (PM) in susceptible animal model is very limited. In this study, we aimed to investigate the association between Beijing ambient particle exposure and the atherosclerosis development in the apolipoprotein E knockout mice (ApoE(-/-) mice). Two parallel exposure chambers were used for whole body exposure among ApoE knockout mice. One of the chambers was supplied with untreated ambient air (PM group) and the other chamber was treated with ambient air filtered by high-efficiency particulate air (HEPA) filter (FA group). Twenty mice were divided into two groups and exposed to ambient PM (n=10 for PM group) or filtered air (n=10 for FA group) for two months from January 18th to March 18th, 2010. During the exposure, the mass concentrations of PM2.5 and PM10 in the two chambers were continuously monitored. Additionally, a receptor source apportionment model of chemical mass balance using 19 organic tracers was applied to determine the contributions of sources on the PM2.5 in terms of natural gas, diesel vehicle, gasoline vehicle, coal burning, vegetable debris, biomass burning and cooking. At the end of the two-month exposure, biomarkers of oxidative stress, inflammation and lipid metabolism in bronchoalveolar lavage fluid (BAL) and blood samples were determined and the plaque area on the aortic endothelium was quantified. In the experiment, the concentrations of PM10 and PM2.5 in PM chamber were 99.45μg/m(3) and 61.0μg/m(3) respectively, while PM2.5 in FA chamber was 17.6μg/m(3). Source apportionment analysis by organic tracers showed that gasoline vehicle (39.9%) and coal burning (24.3%) emission were the two major sources contributing to the mass concentration of PM2.5 in Beijing. Among the ApoE knockout mice, the PM group were significantly higher than the FA group in terms of serum total cholesterol, low-density lipoprotein, tumor necrosis factor-alpha (TNF-alpha) and C-reactive protein as well as TNF-alpha and interleukin-6 in BAL. Also the total antioxidant capacity and oxidized low-density lipoprotein were significantly different between the two groups. In addition, pathological analysis of aortic arch reveals that the plaques area in the PM group increased significantly compared to the FA group. Our results demonstrated that ambient PM exposure could induce considerable oxidative stress and systemic inflammation in ApoE knockout mice and contribute to the progression of atherosclerosis. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

The GAW Aerosol Lidar Observation Network (GALION) as a source of near-real time aerosol profile data for model evaluation and assimilation

NASA Astrophysics Data System (ADS)

Hoff, R. M.; Pappalardo, G.

2010-12-01

In 2007, the WMO Global Atmospheric Watch’s Science Advisory Group on Aerosols described a global network of lidar networks called GAW Aerosol Lidar Observation Network (GALION). GALION has a purpose of providing expanded coverage of aerosol observations for climate and air quality use. Comprised of networks in Asia (AD-NET), Europe (EARLINET and CIS-LINET), North America (CREST and CORALNET), South America (ALINE) and with contribution from global networks such as MPLNET and NDACC, the collaboration provides a unique capability to define aerosol profiles in the vertical. GALION is designed to supplement existing ground-based and column profiling (AERONET, PHOTONS, SKYNET, GAWPFR) stations. In September 2010, GALION held its second workshop and one component of discussion focussed how the network would integrate into model needs. GALION partners have contributed to the Sand and Dust Storm Warning and Analysis System (SDS-WAS) and to assimilation in models such as DREAM. This paper will present the conclusions of those discussions and how these observations can fit into a global model analysis framework. Questions of availability, latency, and aerosol parameters that might be ingested into models will be discussed. An example of where EARLINET and GALION have contributed in near-real time observations was the suite of measurements during the Eyjafjallajokull eruption in Iceland and its impact on European air travel. Lessons learned from this experience will be discussed.

Orthogonal higher order structure and confirmatory factor analysis of the French Wechsler Adult Intelligence Scale (WAIS-III).

PubMed

Golay, Philippe; Lecerf, Thierry

2011-03-01

According to the most widely accepted Cattell-Horn-Carroll (CHC) model of intelligence measurement, each subtest score of the Wechsler Intelligence Scale for Adults (3rd ed.; WAIS-III) should reflect both 1st- and 2nd-order factors (i.e., 4 or 5 broad abilities and 1 general factor). To disentangle the contribution of each factor, we applied a Schmid-Leiman orthogonalization transformation (SLT) to the standardization data published in the French technical manual for the WAIS-III. Results showed that the general factor accounted for 63% of the common variance and that the specific contributions of the 1st-order factors were weak (4.7%-15.9%). We also addressed this issue by using confirmatory factor analysis. Results indicated that the bifactor model (with 1st-order group and general factors) better fit the data than did the traditional higher order structure. Models based on the CHC framework were also tested. Results indicated that a higher order CHC model showed a better fit than did the classical 4-factor model; however, the WAIS bifactor structure was the most adequate. We recommend that users do not discount the Full Scale IQ when interpreting the index scores of the WAIS-III because the general factor accounts for the bulk of the common variance in the French WAIS-III. The 4 index scores cannot be considered to reflect only broad ability because they include a strong contribution of the general factor.

Sensitivity Analysis of Multiple Informant Models When Data are Not Missing at Random

PubMed Central

Blozis, Shelley A.; Ge, Xiaojia; Xu, Shu; Natsuaki, Misaki N.; Shaw, Daniel S.; Neiderhiser, Jenae; Scaramella, Laura; Leve, Leslie; Reiss, David

2014-01-01

Missing data are common in studies that rely on multiple informant data to evaluate relationships among variables for distinguishable individuals clustered within groups. Estimation of structural equation models using raw data allows for incomplete data, and so all groups may be retained even if only one member of a group contributes data. Statistical inference is based on the assumption that data are missing completely at random or missing at random. Importantly, whether or not data are missing is assumed to be independent of the missing data. A saturated correlates model that incorporates correlates of the missingness or the missing data into an analysis and multiple imputation that may also use such correlates offer advantages over the standard implementation of SEM when data are not missing at random because these approaches may result in a data analysis problem for which the missingness is ignorable. This paper considers these approaches in an analysis of family data to assess the sensitivity of parameter estimates to assumptions about missing data, a strategy that may be easily implemented using SEM software. PMID:25221420

Identity effects dominate the impacts of multiple species extinctions on the functioning of complex food webs.

PubMed

Harvey, Eric; Séguin, Annie; Nozais, Christian; Archambault, Philippe; Gravel, Dominique

2013-01-01

Understanding the impacts of species extinctions on the functioning of food webs is a challenging task because of the complexity of ecological interactions. We report the impacts of experimental species extinctions on the functioning of two food webs of freshwater and marine systems. We used a linear model to partition the variance among the multiple components of the diversity effect (linear group richness, nonlinear group richness, and identity). The identity of each functional group was the best explaining variable of ecosystem functioning for both systems. We assessed the contribution of each functional group in multifunctional space and found that, although the effect of functional group varied across ecosystem functions, some functional groups shared common effects on functions. This study is the first experimental demonstration that functional identity dominates the effects of extinctions on ecosystem functioning, suggesting that generalizations are possible despite the inherent complexity of interactions.

Methyl group dynamics in paracetamol and acetanilide: probing the static properties of intermolecular hydrogen bonds formed by peptide groups

NASA Astrophysics Data System (ADS)

Johnson, M. R.; Prager, M.; Grimm, H.; Neumann, M. A.; Kearley, G. J.; Wilson, C. C.

1999-06-01

Measurements of tunnelling and librational excitations for the methyl group in paracetamol and tunnelling excitations for the methyl group in acetanilide are reported. In both cases, results are compared with molecular mechanics calculations, based on the measured low temperature crystal structures, which follow an established recipe. Agreement between calculated and measured methyl group observables is not as good as expected and this is attributed to the presence of comprehensive hydrogen bond networks formed by the peptide groups. Good agreement is obtained with a periodic quantum chemistry calculation which uses density functional methods, these calculations confirming the validity of the one-dimensional rotational model used and the crystal structures. A correction to the Coulomb contribution to the rotational potential in the established recipe using semi-emipircal quantum chemistry methods, which accommodates the modified charge distribution due to the hydrogen bonds, is investigated.

Peer Assessment of an Individual's Contribution to a Group Project.

ERIC Educational Resources Information Center

Conway, Robert; And Others

1993-01-01

In response to optometry student complaints about group scores as an inadequate reflection of individual effort, two different procedures for assessing individual contributions to a group learning project were investigated, one based on evaluations by students outside the group and one using student evaluations of their fellow group members'…

Expanding the Application of Group Interventions: Emergence of Groups in Health Care Settings

ERIC Educational Resources Information Center

Drum, David; Becker, Martin Swanbrow; Hess, Elaine

2011-01-01

Changes in the health care arena and within the specialty of group work are contributing to the increased utilization of groups in health care settings. Psychoeducational, theme, and interpersonal therapy groups are highlighted for their contributions to treating challenging health conditions. An understanding of the evolution of these group…

Neurodegeneration Alters Metabolic Profile and Sirt 1 Signaling in High-Fat-Induced Obese Mice.

PubMed

Lima, Leandro Ceotto Freitas; Saliba, Soraya Wilke; Andrade, João Marcus Oliveira; Cunha, Maria Luisa; Cassini-Vieira, Puebla; Feltenberger, John David; Barcelos, Lucíola Silva; Guimarães, André Luiz Sena; de-Paula, Alfredo Mauricio Batista; de Oliveira, Antônio Carlos Pinheiro; Santos, Sérgio Henrique Sousa

2017-07-01

Different factors may contribute to the development of neurodegenerative diseases. Among them, metabolic syndrome (MS), which has reached epidemic proportions, has emerged as a potential element that may be involved in neurodegeneration. Furthermore, studies have shown the importance of the sirtuin family in neuronal survival and MS, which opens the possibility of new pharmacological targets. This study investigates the influence of sirtuin metabolic pathways by examining the functional capacities of glucose-induced obesity in an excitotoxic state induced by a quinolinic acid (QA) animal model. Mice were divided into two groups that received different diets for 8 weeks: one group received a regular diet, and the other group received a high-fat diet (HF) to induce MS. The animals were submitted to a stereotaxic surgery and subdivided into four groups: Standard (ST), Standard-QA (ST-QA), HF and HF-QA. The QA groups were given a 250 nL quinolinic acid injection in the right striatum and PBS was injected in the other groups. Obese mice presented with a weight gain of 40 % more than the ST group beyond acquiring an insulin resistance. QA induced motor impairment and neurodegeneration in both ST-QA and HF-QA, although no difference was observed between these groups. The HF-QA group showed a reduction in adiposity when compared with the groups that received PBS. Therefore, the HF-QA group demonstrated a commitment-dependent metabolic pathway. The results suggest that an obesogenic diet does not aggravate the neurodegeneration induced by QA. However, the excitotoxicity induced by QA promotes a sirtuin pathway impairment that contributes to metabolic changes.

Protein attributes contribute to halo-stability, bioinformatics approach

PubMed Central

2011-01-01

Halophile proteins can tolerate high salt concentrations. Understanding halophilicity features is the first step toward engineering halostable crops. To this end, we examined protein features contributing to the halo-toleration of halophilic organisms. We compared more than 850 features for halophilic and non-halophilic proteins with various screening, clustering, decision tree, and generalized rule induction models to search for patterns that code for halo-toleration. Up to 251 protein attributes selected by various attribute weighting algorithms as important features contribute to halo-stability; from them 14 attributes selected by 90% of models and the count of hydrogen gained the highest value (1.0) in 70% of attribute weighting models, showing the importance of this attribute in feature selection modeling. The other attributes mostly were the frequencies of di-peptides. No changes were found in the numbers of groups when K-Means and TwoStep clustering modeling were performed on datasets with or without feature selection filtering. Although the depths of induced trees were not high, the accuracies of trees were higher than 94% and the frequency of hydrophobic residues pointed as the most important feature to build trees. The performance evaluation of decision tree models had the same values and the best correctness percentage recorded with the Exhaustive CHAID and CHAID models. We did not find any significant difference in the percent of correctness, performance evaluation, and mean correctness of various decision tree models with or without feature selection. For the first time, we analyzed the performance of different screening, clustering, and decision tree algorithms for discriminating halophilic and non-halophilic proteins and the results showed that amino acid composition can be used to discriminate between halo-tolerant and halo-sensitive proteins. PMID:21592393

Modeling the Impact of Motivation, Personality, and Emotion on Social Behavior

NASA Astrophysics Data System (ADS)

Miller, Lynn C.; Read, Stephen J.; Zachary, Wayne; Rosoff, Andrew

Models seeking to predict human social behavior must contend with multiple sources of individual and group variability that underlie social behavior. One set of interrelated factors that strongly contribute to that variability - motivations, personality, and emotions - has been only minimally incorporated in previous computational models of social behavior. The Personality, Affect, Culture (PAC) framework is a theory-based computational model that addresses this gap. PAC is used to simulate social agents whose social behavior varies according to their personalities and emotions, which, in turn, vary according to their motivations and underlying motive control parameters. Examples involving disease spread and counter-insurgency operations show how PAC can be used to study behavioral variability in different social contexts.

Does maternal asthma contribute to racial/ethnic disparities in obstetric and neonatal complications?

PubMed Central

Flores, Katrina F.; Robledo, Candace A.; Hwang, Beom Seuk; Leishear, Kira; Grantz, Katherine Laughon; Mendola, Pauline

2015-01-01

Purpose Examine whether maternal asthma contributes to racial/ethnic differences in obstetric and neonatal complications. Methods Data on White (n=110,603), Black (n=50,284) and Hispanic (n=38,831) singleton deliveries came from the Consortium on Safe Labor. Multi-level logistic regression models, with an interaction term for asthma and race/ethnicity, estimated within-group adjusted odds ratios (aOR) for gestational diabetes, gestational hypertension, preeclampsia, placental abruption, premature rupture of membranes, preterm delivery, maternal hemorrhage, NICU admissions, small for gestational age (SGA), apnea, respiratory distress syndrome, transient tachypnea of the newborn, anemia and hyperbilirubinemia after adjustment for clinical and demographic confounders. Non-asthmatics of the same racial/ethnic group were the reference group. Results Compared to non-asthmatics, White asthmatics had increased odds of preeclampsia (aOR 1.28; 95% CI: 1.15–1.43) and maternal hemorrhage (1.14; 1.04–1.23). White and Hispanic infants were more likely to have NICU admissions (1.19; 1.11–1.28; 1.16; 1.02–1.32, respectively) and be SGA (1.11; 1.02–1.20; 1.26; 1.10–1.44, respectively) and Hispanic infants were more likely to have apnea (1.32; 1.02–1.69). Conclusions Maternal asthma did not impact most obstetric and neonatal complication risks within racial/ethnic groups. Despite their increased risk for both asthma and many complications, our findings for Black women were null. Asthma did not contribute to racial/ethnic disparities in complications. PMID:25724829

Statistical symmetry restoration in fully developed turbulence: Renormalization group analysis of two models.

PubMed

Antonov, N V; Gulitskiy, N M; Kostenko, M M; Malyshev, A V

2018-03-01

In this paper we consider the model of incompressible fluid described by the stochastic Navier-Stokes equation with finite correlation time of a random force. Inertial-range asymptotic behavior of fully developed turbulence is studied by means of the field theoretic renormalization group within the one-loop approximation. It is corroborated that regardless of the values of model parameters and initial data the inertial-range behavior of the model is described by the limiting case of vanishing correlation time. This indicates that the Galilean symmetry of the model violated by the "colored" random force is restored in the inertial range. This regime corresponds to the only nontrivial fixed point of the renormalization group equation. The stability of this point depends on the relation between the exponents in the energy spectrum E∝k^{1-y} and the dispersion law ω∝k^{2-η}. The second analyzed problem is the passive advection of a scalar field by this velocity ensemble. Correlation functions of the scalar field exhibit anomalous scaling behavior in the inertial-convective range. We demonstrate that in accordance with Kolmogorov's hypothesis of the local symmetry restoration the main contribution to the operator product expansion is given by the isotropic operator, while anisotropic terms should be considered only as corrections.

Statistical symmetry restoration in fully developed turbulence: Renormalization group analysis of two models

NASA Astrophysics Data System (ADS)

Antonov, N. V.; Gulitskiy, N. M.; Kostenko, M. M.; Malyshev, A. V.

2018-03-01

In this paper we consider the model of incompressible fluid described by the stochastic Navier-Stokes equation with finite correlation time of a random force. Inertial-range asymptotic behavior of fully developed turbulence is studied by means of the field theoretic renormalization group within the one-loop approximation. It is corroborated that regardless of the values of model parameters and initial data the inertial-range behavior of the model is described by the limiting case of vanishing correlation time. This indicates that the Galilean symmetry of the model violated by the "colored" random force is restored in the inertial range. This regime corresponds to the only nontrivial fixed point of the renormalization group equation. The stability of this point depends on the relation between the exponents in the energy spectrum E ∝k1 -y and the dispersion law ω ∝k2 -η . The second analyzed problem is the passive advection of a scalar field by this velocity ensemble. Correlation functions of the scalar field exhibit anomalous scaling behavior in the inertial-convective range. We demonstrate that in accordance with Kolmogorov's hypothesis of the local symmetry restoration the main contribution to the operator product expansion is given by the isotropic operator, while anisotropic terms should be considered only as corrections.

Major role of nutrient supply in the control of picophytoplankton community structure

NASA Astrophysics Data System (ADS)

Mouriño, B.; Agusti, S.; Bode, A.; Cermeno, P.; Chouciño, P.; da Silva, J. C. B.; Fernández-Castro, B.; Gasol, J.; Gil Coto, M.; Graña, R.; Latasa, M.; Lubián, L.; Marañón, E.; Moran, X. A.; Moreno, E.; Moreira-Coello, V.; Otero-Ferrer, J. L.; Ruiz Villarreal, M.; Scharek, R.; Vallina, S. M.; Varela, M.; Villamaña, M.

2016-02-01

The Margalef's mandala (1978) is a simplified bottom-up control model that explains how mixing and nutrient concentration determine the composition of marine phytoplankton communities. Due to the difficulties of measuring turbulence in the field, previous attempts to verify this model have applied different proxies for nutrient supply, and very often used interchangeably the terms mixing and stratification. Moreover, because the mandala was conceived before the discovery of smaller phytoplankton groups (picoplankton <2 μm), it describes only the succession of vegetative phases of microplankton. In order to test the applicability of the classical mandala to picoplankton groups, we used a multidisciplinary approach including specifically designed field observations supported by remote sensing, database analyses, and modeling and laboratory chemostat experiments. Simultaneous estimates of nitrate diffusive fluxes, derived from microturbulence observations, and picoplankton abundance collected in more than 200 stations, spanning widely different hydrographic regimes, showed that the contribution of eukaryotes to picoautotrophic biomass increases with nutrient supply, whereas that of picocyanobacteria shows the opposite trend. These findings were supported by laboratory and modeling chemostat experiments that reproduced the competitive dynamics between picoeukaryote sand picocyanobacteria as a function of changing nutrient supply. Our results indicate that nutrient supply controls the distribution of picoplankton functional groups in the ocean, further supporting the model proposed by Margalef.

Influence of Tissue Microstructure on Shear Wave Speed Measurements in Plane Shear Wave Elastography: A Computational Study in Lossless Fibrotic Liver Media.

PubMed

Wang, Yu; Jiang, Jingfeng

2018-01-01

Shear wave elastography (SWE) has been used to measure viscoelastic properties for characterization of fibrotic livers. In this technique, external mechanical vibrations or acoustic radiation forces are first transmitted to the tissue being imaged to induce shear waves. Ultrasonically measured displacement/velocity is then utilized to obtain elastographic measurements related to shear wave propagation. Using an open-source wave simulator, k-Wave, we conducted a case study of the relationship between plane shear wave measurements and the microstructure of fibrotic liver tissues. Particularly, three different virtual tissue models (i.e., a histology-based model, a statistics-based model, and a simple inclusion model) were used to represent underlying microstructures of fibrotic liver tissues. We found underlying microstructures affected the estimated mean group shear wave speed (SWS) under the plane shear wave assumption by as much as 56%. Also, the elastic shear wave scattering resulted in frequency-dependent attenuation coefficients and introduced changes in the estimated group SWS. Similarly, the slope of group SWS changes with respect to the excitation frequency differed as much as 78% among three models investigated. This new finding may motivate further studies examining how elastic scattering may contribute to frequency-dependent shear wave dispersion and attenuation in biological tissues.

New Frontiers in Analyzing Dynamic Group Interactions: Bridging Social and Computer Science

PubMed Central

Lehmann-Willenbrock, Nale; Hung, Hayley; Keyton, Joann

2017-01-01

This special issue on advancing interdisciplinary collaboration between computer scientists and social scientists documents the joint results of the international Lorentz workshop, “Interdisciplinary Insights into Group and Team Dynamics,” which took place in Leiden, The Netherlands, July 2016. An equal number of scholars from social and computer science participated in the workshop and contributed to the papers included in this special issue. In this introduction, we first identify interaction dynamics as the core of group and team models and review how scholars in social and computer science have typically approached behavioral interactions in groups and teams. Next, we identify key challenges for interdisciplinary collaboration between social and computer scientists, and we provide an overview of the different articles in this special issue aimed at addressing these challenges. PMID:29249891

New Frontiers in Analyzing Dynamic Group Interactions: Bridging Social and Computer Science.

PubMed

Lehmann-Willenbrock, Nale; Hung, Hayley; Keyton, Joann

2017-10-01

This special issue on advancing interdisciplinary collaboration between computer scientists and social scientists documents the joint results of the international Lorentz workshop, "Interdisciplinary Insights into Group and Team Dynamics," which took place in Leiden, The Netherlands, July 2016. An equal number of scholars from social and computer science participated in the workshop and contributed to the papers included in this special issue. In this introduction, we first identify interaction dynamics as the core of group and team models and review how scholars in social and computer science have typically approached behavioral interactions in groups and teams. Next, we identify key challenges for interdisciplinary collaboration between social and computer scientists, and we provide an overview of the different articles in this special issue aimed at addressing these challenges.

An Integrative Approach to Computational Modelling of the Gene Regulatory Network Controlling Clostridium botulinum Type A1 Toxin Production

PubMed Central

Walshaw, John; Peck, Michael W.; Barker, Gary C.

2016-01-01

Clostridium botulinum produces botulinum neurotoxins (BoNTs), highly potent substances responsible for botulism. Currently, mathematical models of C. botulinum growth and toxigenesis are largely aimed at risk assessment and do not include explicit genetic information beyond group level but integrate many component processes, such as signalling, membrane permeability and metabolic activity. In this paper we present a scheme for modelling neurotoxin production in C. botulinum Group I type A1, based on the integration of diverse information coming from experimental results available in the literature. Experiments show that production of BoNTs depends on the growth-phase and is under the control of positive and negative regulatory elements at the intracellular level. Toxins are released as large protein complexes and are associated with non-toxic components. Here, we systematically review and integrate those regulatory elements previously described in the literature for C. botulinum Group I type A1 into a population dynamics model, to build the very first computational model of toxin production at the molecular level. We conduct a validation of our model against several items of published experimental data for different wild type and mutant strains of C. botulinum Group I type A1. The result of this process underscores the potential of mathematical modelling at the cellular level, as a means of creating opportunities in developing new strategies that could be used to prevent botulism; and potentially contribute to improved methods for the production of toxin that is used for therapeutics. PMID:27855161

Present status of numerical modeling of hydrogen negative ion source plasmas and its comparison with experiments: Japanese activities and their collaboration with experimental groups

NASA Astrophysics Data System (ADS)

Hatayama, A.; Nishioka, S.; Nishida, K.; Mattei, S.; Lettry, J.; Miyamoto, K.; Shibata, T.; Onai, M.; Abe, S.; Fujita, S.; Yamada, S.; Fukano, A.

2018-06-01

The present status of kinetic modeling of particle dynamics in hydrogen negative ion (H‑) source plasmas and their comparisons with experiments are reviewed and discussed with some new results. The main focus is placed on the following topics, which are important for the research and development of H‑ sources for intense and high-quality H‑ ion beams: (i) effects of non-equilibrium features of electron energy distribution function on volume and surface H‑ production, (ii) the origin of the spatial non-uniformity in giant multi-cusp arc-discharge H‑ sources, (iii) capacitive to inductive (E to H) mode transition in radio frequency-inductively coupled plasma H‑ sources and (iv) extraction physics of H‑ ions and beam optics, especially the present understanding of the meniscus formation in strongly electronegative plasmas (so-called ion–ion plasmas) and its effect on beam optics. For these topics, mainly Japanese modeling activities, and their domestic and international collaborations with experimental studies, are introduced with some examples showing how models have been improved and to what extent the modeling studies can presently contribute to improving the source performance. Close collaboration between experimental and modeling activities is indispensable for the validation/improvement of the modeling and its contribution to the source design/development.

Comparison of isocratic retention models for hydrophilic interaction liquid chromatographic separation of native and fluorescently labeled oligosaccharides.

PubMed

Česla, Petr; Vaňková, Nikola; Křenková, Jana; Fischer, Jan

2016-03-18

In this work, we have investigated retention of maltooligosaccharides and their fluorescent derivatives in hydrophilic interaction liquid chromatography using four different stationary phases. The non-derivatized maltooligosaccharides (maltose to maltoheptaose) and their derivatives with 2-aminobenzoic acid, 2-aminobenzamide, 2-aminopyridine and 8-aminonaphthalene-1,3,6-trisulfonic acid were analyzed on silica gel, aminopropyl silica, amide (carbamoyl-bonded silica) and ZIC-HILIC zwitterionic sulfobetain bonded phase. The partitioning of the analytes between the bulk mobile phase and adsorbed water-rich layer, polar and ionic interactions of analytes with stationary phase have been evaluated and compared. The effects of the mobile phase additives (0.1% (v/v) of acetic acid and ammonium acetate in concentration range 5-30 mmol L(-1)) on retention were described. The suitability of different models for prediction of retention was tested including linear solvent strength model, quadratic model, mixed-mode model, and empirical Neue-Kuss model. The mixed-mode model was extended to the parameter describing the contribution of monomeric glucose unit to the retention of non-derivatized and derivatized maltooligosaccharides, which was used for evaluation of contribution of both, oligosaccharide backbone and end-group to retention. Copyright © 2016 Elsevier B.V. All rights reserved.

Object Tracking Using Adaptive Covariance Descriptor and Clustering-Based Model Updating for Visual Surveillance

PubMed Central

Qin, Lei; Snoussi, Hichem; Abdallah, Fahed

2014-01-01

We propose a novel approach for tracking an arbitrary object in video sequences for visual surveillance. The first contribution of this work is an automatic feature extraction method that is able to extract compact discriminative features from a feature pool before computing the region covariance descriptor. As the feature extraction method is adaptive to a specific object of interest, we refer to the region covariance descriptor computed using the extracted features as the adaptive covariance descriptor. The second contribution is to propose a weakly supervised method for updating the object appearance model during tracking. The method performs a mean-shift clustering procedure among the tracking result samples accumulated during a period of time and selects a group of reliable samples for updating the object appearance model. As such, the object appearance model is kept up-to-date and is prevented from contamination even in case of tracking mistakes. We conducted comparing experiments on real-world video sequences, which confirmed the effectiveness of the proposed approaches. The tracking system that integrates the adaptive covariance descriptor and the clustering-based model updating method accomplished stable object tracking on challenging video sequences. PMID:24865883

Hydration and conformational equilibria of simple hydrophobic and amphiphilic solutes.

PubMed Central

Ashbaugh, H S; Kaler, E W; Paulaitis, M E

1998-01-01

We consider whether the continuum model of hydration optimized to reproduce vacuum-to-water transfer free energies simultaneously describes the hydration free energy contributions to conformational equilibria of the same solutes in water. To this end, transfer and conformational free energies of idealized hydrophobic and amphiphilic solutes in water are calculated from explicit water simulations and compared to continuum model predictions. As benchmark hydrophobic solutes, we examine the hydration of linear alkanes from methane through hexane. Amphiphilic solutes were created by adding a charge of +/-1e to a terminal methyl group of butane. We find that phenomenological continuum parameters fit to transfer free energies are significantly different from those fit to conformational free energies of our model solutes. This difference is attributed to continuum model parameters that depend on solute conformation in water, and leads to effective values for the free energy/surface area coefficient and Born radii that best describe conformational equilibrium. In light of these results, we believe that continuum models of hydration optimized to fit transfer free energies do not accurately capture the balance between hydrophobic and electrostatic contributions that determines the solute conformational state in aqueous solution. PMID:9675177

Ionospheric limitations to time transfer by satellite

NASA Technical Reports Server (NTRS)

Knowles, S. H.

1983-01-01

The ionosphere can contribute appreciable group delay and phase change to radio signals traversing it; this can constitute a fundamental limitation to the accuracy of time and frequency measurements using satellites. Because of the dispersive nature of the ionosphere, the amount of delay is strongly frequency-dependent. Ionospheric compensation is necessary for the most precise time transfer and frequency measurements, with a group delay accuracy better than 10 nanoseconds. A priori modeling is not accurate to better than 25%. The dual-frequency compensation method holds promise, but has not been rigorously experimentally tested. Irregularities in the ionosphere must be included in the compensation process.

The 7th Asia-Pacific Transport Working Group (APTWG) meeting

NASA Astrophysics Data System (ADS)

Ida, K.; Kong, D. F.; Fujita, T.; Ido, T.; Ko, W. H.; Maeyama, S.

2018-01-01

This conference report summarizes the contributions to, and discussions at, the 7th Asia-Pacific Transport Working Group Meeting held at Nagoya University, Japan, during 5-8 June 2017. The topics of the meeting were organized under four main headings: (1) turbulence and blob at the boundary of magnetic topology, (2) model reduction and experiments for validation, (3) mode competition in turbulence and MHD driven by energetic particle, (4) mechanism determining plasma flows and their impact on transport and MHD. The Young Researchers Forum which was held in this meeting is also described in this report.

Understanding the City Size Wage Gap*

PubMed Central

Baum-Snow, Nathaniel; Pavan, Ronni

2013-01-01

In this paper, we decompose city size wage premia into various components. We base these decompositions on an estimated on-the-job search model that incorporates latent ability, search frictions, firm-worker match quality, human capital accumulation and endogenous migration between large, medium and small cities. Counterfactual simulations of the model indicate that variation in returns to experience and differences in wage intercepts across location type are the most important mechanisms contributing to observed city size wage premia. Variation in returns to experience is more important for generating wage premia between large and small locations while differences in wage intercepts are more important for generating wage premia betwen medium and small locations. Sorting on unobserved ability within education group and differences in labor market search frictions and distributions of firm-worker match quality contribute little to observed city size wage premia. These conclusions hold for separate samples of high school and college graduates. PMID:24273347

Understanding Housing Delays and Relocations Within the Housing First Model.

PubMed

Zerger, Suzanne; Pridham, Katherine Francombe; Jeyaratnam, Jeyagobi; Hwang, Stephen W; O'Campo, Patricia; Kohli, Jaipreet; Stergiopoulos, Vicky

2016-01-01

This study explores factors contributing to delays and relocations during the implementation of the Housing First model in Toronto, Ontario. While interruptions in housing tenure are expected en route to recovery and housing stability, consumer and service provider views on finding and keeping housing remain largely unknown. In-person interviews and focus groups were conducted with 48 study participants, including 23 case managers or housing workers and 25 consumers. The following three factors contributed to housing delays and transfers: (1) the effectiveness of communication and collaboration among consumers and service providers, (2) consumer-driven preferences and ambivalence, and (3) provider prioritization of consumer choice over immediate housing access. Two strategies--targeted communications and consumer engagement in housing searches--supported the housing process. Several factors affect the timing and stability of housing. Communication between and among providers and consumers, and a shared understanding of consumer choice, can further support choice and recovery.

Youth violence in South Africa: exposure, attitudes, and resilience in Zulu adolescents.

PubMed

Choe, Daniel Ewon; Zimmerman, Marc A; Devnarain, Bashi

2012-01-01

Exposure to violence is common in South Africa. Yet, few studies examine how violence exposure contributes to South African adolescents' participation in youth violence. The aims of this study were to examine effects of different violence exposures on violent attitudes and behavior, to test whether attitudes mediated effects of violence exposures on violent behavior, and to test whether adult involvement had protective or promotive effects. Questionnaires were administered to 424 Zulu adolescents in township high schools around Durban, South Africa. Structural equation modeling (SEM) was used to test associations among violence exposures and both violent attitudes and behavior. Victimization, witnessing violence, and friends' violent behavior contributed directly to violent behavior. Only family conflict and friends' violence influenced violent attitudes. Attitudes mediated effects of friends' violence on violent behavior. Multiple-group SEM indicated that adult involvement fit a protective model of resilience. These findings are discussed regarding their implications for prevention.

Understanding the City Size Wage Gap.

PubMed

Baum-Snow, Nathaniel; Pavan, Ronni

2012-01-01

In this paper, we decompose city size wage premia into various components. We base these decompositions on an estimated on-the-job search model that incorporates latent ability, search frictions, firm-worker match quality, human capital accumulation and endogenous migration between large, medium and small cities. Counterfactual simulations of the model indicate that variation in returns to experience and differences in wage intercepts across location type are the most important mechanisms contributing to observed city size wage premia. Variation in returns to experience is more important for generating wage premia between large and small locations while differences in wage intercepts are more important for generating wage premia betwen medium and small locations. Sorting on unobserved ability within education group and differences in labor market search frictions and distributions of firm-worker match quality contribute little to observed city size wage premia. These conclusions hold for separate samples of high school and college graduates.

The association of pain and fear of movement/reinjury with function during anterior cruciate ligament reconstruction rehabilitation.

PubMed

Chmielewski, Terese L; Jones, Debi; Day, Tim; Tillman, Susan M; Lentz, Trevor A; George, Steven Z

2008-12-01

Cross-sectional. To measure fear of movement/reinjury levels and determine the association with function at different timeframes during anterior cruciate ligament (ACL) reconstruction rehabilitation. We hypothesized that fear of movement/reinjury would decrease during rehabilitation and be inversely related with function. Fear of movement/reinjury can prevent return to sports after ACL reconstruction, but it has not been studied during rehabilitation. Demographic data and responses on the shortened version of Tampa Scale for Kinesiophobia (TSK-11), 8-Item Short-Form Health Survey (SF-8), and International Knee Documentation Committee (IKDC) subjective form were extracted from a clinical database for 97 patients in the first year after ACL reconstruction. Three groups were formed: group 1, less than or equal to 90 days; group 2, 91 to 180 days; group 3: 181 to 372 days post-ACL reconstruction. Group differences in TSK-11 score, SF-8 bodily pain rating, and IKDC scores were determined. Hierarchical linear regression models were created for each group, with IKDC score as the dependent variable and demographic factors, SF-8 bodily pain rating, and TSK-11 score as independent variables. TSK-11 score was higher in group 1 than in group 3 (P < .05). Across the groups, SF-8 bodily pain rating decreased (P < .001) and IKDC score increased (P < .001). SF-8 bodily pain rating was a significant factor in the regression model for all groups, whereas TSK-11 score only contributed to the regression model in group 3 (partial correlation, -0.529). Pain was consistently associated with function across the timeframes studied. Fear of movement/reinjury levels appear to decrease during ACL reconstruction rehabilitation and are associated with function in the timeframe when patients return to sports. Prognosis, level 4.

PREFACE: Theory, Modelling and Computational methods for Semiconductors

NASA Astrophysics Data System (ADS)

Migliorato, Max; Probert, Matt

2010-04-01

These conference proceedings contain the written papers of the contributions presented at the 2nd International Conference on: Theory, Modelling and Computational methods for Semiconductors. The conference was held at the St Williams College, York, UK on 13th-15th Jan 2010. The previous conference in this series took place in 2008 at the University of Manchester, UK. The scope of this conference embraces modelling, theory and the use of sophisticated computational tools in Semiconductor science and technology, where there is a substantial potential for time saving in R&D. The development of high speed computer architectures is finally allowing the routine use of accurate methods for calculating the structural, thermodynamic, vibrational and electronic properties of semiconductors and their heterostructures. This workshop ran for three days, with the objective of bringing together UK and international leading experts in the field of theory of group IV, III-V and II-VI semiconductors together with postdocs and students in the early stages of their careers. The first day focused on providing an introduction and overview of this vast field, aimed particularly at students at this influential point in their careers. We would like to thank all participants for their contribution to the conference programme and these proceedings. We would also like to acknowledge the financial support from the Institute of Physics (Computational Physics group and Semiconductor Physics group), the UK Car-Parrinello Consortium, Accelrys (distributors of Materials Studio) and Quantumwise (distributors of Atomistix). The Editors Acknowledgements Conference Organising Committee: Dr Matt Probert (University of York) and Dr Max Migliorato (University of Manchester) Programme Committee: Dr Marco Califano (University of Leeds), Dr Jacob Gavartin (Accelrys Ltd, Cambridge), Dr Stanko Tomic (STFC Daresbury Laboratory), Dr Gabi Slavcheva (Imperial College London) Proceedings edited and compiled by Dr Max Migliorato and Dr Matt Probert

Building partnerships: a pilot study of stakeholders' attitudes on technology disruption in behavioral health delivery and research.

PubMed

Sucala, Madalina; Nilsen, Wendy; Muench, Frederick

2017-12-01

Collaborations between scientists, care providers, and technology industry professionals are becoming more relevant for developing, testing, and implementing behavioral health technologies. As the need for such partnerships increases, it is important to understand stakeholders' attitudes about their role in partnering for developing such technologies and how much do they expect technology to impact behavioral research and care. The aim of this study was to investigate how much technology disruption do stakeholders expect in healthcare, as well as their perceived contribution in partnering for developing behavioral health technologies. Stakeholders (N = 74) responded to an online convenience sampling survey. Over 89% of participants reported expecting that technology will bring at least a moderate amount of disruption in the current models of behavioral healthcare, with respondents with the most experience in digital health expecting the most disruption. As for their perception of each other's role in partnering for developing behavioral health technologies, one group's weakness was considered to be complemented by another group's strength. Academics were perceived as having more theoretical and research expertise but being less technology-savvy, while industry professionals were considered to excel at technological and marketing activities. Providers were considered to have the most clinical and real-world healthcare industry expertise. Our results indicate that technology is expected to disrupt current healthcare models, while also highlighting the need for collaboration, as no single group was considered to have sufficient expertise and resources to develop successful, effective behavioral health technologies on its own. These results may contribute to a better understanding of how technology disruption is affecting behavioral healthcare from the standpoint of its key players, which may lead to better collaborative models of research and care delivery.

Decomposing health inequality with population-based surveys: a case study in Rwanda.

PubMed

Liu, Kai; Lu, Chunling

2018-05-10

Ensuring equal access to care and providing financial risk protection are at the center of the global health agenda. While Rwanda has made impressive progress in improving health outcomes, inequalities in medical care utilization and household catastrophic health spending (HCHS) between the impoverished and non-impoverished populations persist. Decomposing inequalities will help us understand the factors contributing to inequalities and design effective policy instruments in reducing inequalities. This study aims to decompose the inequalities in medical care utilization among those reporting illnesses and HCHS between the poverty and non-poverty groups in Rwanda. Using the 2005 and 2010 nationally representative Integrated Living Conditions Surveys, our analysis focuses on measuring contributions to inequalities from poverty status and other sources. We conducted multivariate logistic regression analysis to obtain poverty's contribution to inequalities by controlling for all observed covariates. We used multivariate nonlinear decomposition method with logistic regression models to partition the relative and absolute contributions from other sources to inequalities due to compositional or response effects. Poverty status accounted for the majority of inequalities in medical care utilization (absolute contribution 0.093 in 2005 and 0.093 in 2010) and HCHS (absolute contribution 0.070 in 2005 and 0.032 in 2010). Health insurance status (absolute contribution 0.0076 in 2005 and 0.0246 in 2010) and travel time to health centers (absolute contribution 0.0025 in 2005 and 0.0014 in 2010) were significant contributors to inequality in medical care utilization. Health insurance status (absolute contribution 0.0021 in 2005 and 0.0011 in 2010), having under-five children (absolute contribution 0.0012 in 2005 and 0.0011 in 2010), and having disabled family members (absolute contribution 0.0002 in 2005 and 0.0001 in 2010) were significant contributors to inequality in HCHS. Between 2005 and 2010, the main sources of the inequalities remained unchanged. Expanding insurance coverage and reducing travel time to health facilities for those living in poverty could be used as policy instruments to mitigate inequalities in medical care utilization and HCHS between the poverty and non-poverty groups.

"Hot Spots" of Land Atmosphere Coupling

NASA Technical Reports Server (NTRS)

Koster, Randal D.; Dirmeyer, Paul A.; Guo, Zhi-Chang; Bonan, Gordan; Chan, Edmond; Cox, Peter; Gordon, T. C.; Kanae, Shinjiro; Kowalczyk, Eva; Lawrence, David

2004-01-01

Previous estimates of land-atmosphere interaction (the impact of soil moisture on precipitation) have been limited by a severe paucity of relevant observational data and by the model-dependence of the various computational estimates. To counter this limitation, a dozen climate modeling groups have recently performed the same highly-controlled numerical experiment as part of a coordinated intercomparison project. This allows, for the first time ever, a superior multi-model approach to the estimation of the regions on the globe where precipitation is affected by soil moisture anomalies during Northern Hemisphere summer. Such estimation has many potential benefits; it can contribute, for example, to seasonal rainfall prediction efforts.

Computational social network modeling of terrorist recruitment.

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

Berry, Nina M.; Turnley, Jessica Glicken; Smrcka, Julianne D.

2004-10-01

The Seldon terrorist model represents a multi-disciplinary approach to developing organization software for the study of terrorist recruitment and group formation. The need to incorporate aspects of social science added a significant contribution to the vision of the resulting Seldon toolkit. The unique addition of and abstract agent category provided a means for capturing social concepts like cliques, mosque, etc. in a manner that represents their social conceptualization and not simply as a physical or economical institution. This paper provides an overview of the Seldon terrorist model developed to study the formation of cliques, which are used as the majormore » recruitment entity for terrorist organizations.« less

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

Saravanan, Ramalingam

During the course of this project, we have accomplished the following: 1) Explored the parameter space of component models to minimize regional model bias 2) Assessed the impact of air-sea interaction on hurricanes, focusing in particular on the role of the oceanic barrier layer 3) Contributed to the activities of the U.S. CLIVAR Hurricane Working Group 4) Assessed the impact of lateral and lower boundary conditions on extreme flooding events in the U.S. Midwest in regional model simulations 5) Analyzed the concurrent impact of El Niño-Southern Oscillation and Atlantic Meridional Mode on Atlantic Hurricane activity using observations and regional modelmore » simulations« less

Decoherence and discrete symmetries in deformed relativistic kinematics

NASA Astrophysics Data System (ADS)

Arzano, Michele

2018-01-01

Models of deformed Poincaré symmetries based on group valued momenta have long been studied as effective modifications of relativistic kinematics possibly capturing quantum gravity effects. In this contribution we show how they naturally lead to a generalized quantum time evolution of the type proposed to model fundamental decoherence for quantum systems in the presence of an evaporating black hole. The same structures which determine such generalized evolution also lead to a modification of the action of discrete symmetries and of the CPT operator. These features can in principle be used to put phenomenological constraints on models of deformed relativistic symmetries using precision measurements of neutral kaons.

[Promotion effect of stromal cell-derived factor 1 on the migration of epidermal stem cells in the healing process of frostbite-wound model ex vivo].

PubMed

Gan, Lu; Cao, Chuan; Li, Shi-rong; Chai, Lin-lin; Guo, Rui; Xiang, Guang-jin; Zhao, Shu-wen

2010-06-01

To study the promotion effect of stromal cell-derived factor 1 (SDF-1) on the migration of epidermal stem cells (ESC) in the healing process of frostbite-wound model ex vivo. A three-dimensional model of full-thickness frostbite of skin was constructed (with slot-like wound) out of skin equivalent. The expression of SDF-1 in wound stroma was observed with immunohistochemistry staining on post injury days (PID) 3 and 7. The model frostbite wounds were divided into control group (treated with PBS 50 microL per wound), SDF-1 group (treated with 100 ng/mL SDF-1, 50 microL per wound), and AMD3100 group [treated with 100 ng/mL AMD3100 (50 microL per wound) for 30 minutes, and then SDF-1 50 microL was added per wound]. The redistribution of ESC around wound was observed. The expression of SDF-1 in wound stroma increased gradually on PID 3 and 7. Compared with those in control and AMD3100 groups, there were more ESC and epithelial cell layers, and more integrin beta(1)-positive cells appeared at the basal layer of wound in SDF-1 group, and some of the positive cells migrated upward to epidermis. SDF-1 contributes to wound repair through promoting ESC to migrate toward and gather around wound edge. This may be one of the mechanisms of ESC participating in wound repair.

Improved AIOMFAC model parameterisation of the temperature dependence of activity coefficients for aqueous organic mixtures

NASA Astrophysics Data System (ADS)

Ganbavale, G.; Zuend, A.; Marcolli, C.; Peter, T.

2015-01-01

This study presents a new, improved parameterisation of the temperature dependence of activity coefficients in the AIOMFAC (Aerosol Inorganic-Organic Mixtures Functional groups Activity Coefficients) model applicable for aqueous as well as water-free organic solutions. For electrolyte-free organic and organic-water mixtures the AIOMFAC model uses a group-contribution approach based on UNIFAC (UNIversal quasi-chemical Functional-group Activity Coefficients). This group-contribution approach explicitly accounts for interactions among organic functional groups and between organic functional groups and water. The previous AIOMFAC version uses a simple parameterisation of the temperature dependence of activity coefficients, aimed to be applicable in the temperature range from ~ 275 to ~ 400 K. With the goal to improve the description of a wide variety of organic compounds found in atmospheric aerosols, we extend the AIOMFAC parameterisation for the functional groups carboxyl, hydroxyl, ketone, aldehyde, ether, ester, alkyl, aromatic carbon-alcohol, and aromatic hydrocarbon to atmospherically relevant low temperatures. To this end we introduce a new parameterisation for the temperature dependence. The improved temperature dependence parameterisation is derived from classical thermodynamic theory by describing effects from changes in molar enthalpy and heat capacity of a multi-component system. Thermodynamic equilibrium data of aqueous organic and water-free organic mixtures from the literature are carefully assessed and complemented with new measurements to establish a comprehensive database, covering a wide temperature range (~ 190 to ~ 440 K) for many of the functional group combinations considered. Different experimental data types and their processing for the estimation of AIOMFAC model parameters are discussed. The new AIOMFAC parameterisation for the temperature dependence of activity coefficients from low to high temperatures shows an overall improvement of 28% in comparison to the previous model version, when both versions are compared to our database of experimentally determined activity coefficients and related thermodynamic data. When comparing the previous and new AIOMFAC model parameterisations to the subsets of experimental data with all temperatures below 274 K or all temperatures above 322 K (i.e. outside a 25 K margin of the reference temperature of 298 K), applying the new parameterisation leads to 37% improvement in each of the two temperature ranges considered. The new parameterisation of AIOMFAC agrees well with a large number of experimental data sets. Larger model-measurement discrepancies were found particularly for some of the systems containing multi-functional organic compounds. The affected systems were typically also poorly represented at room temperature and further improvements will be necessary to achieve better performance of AIOMFAC in these cases (assuming the experimental data are reliable). The performance of the AIOMFAC parameterisation is typically better for systems containing relatively small organic compounds and larger deviations may occur in mixtures where molecules of high structural complexity such as highly oxygenated compounds or molecules of high molecular mass (e.g. oligomers) prevail. Nevertheless, the new parameterisation enables the calculation of activity coefficients for a wide variety of different aqueous/water-free organic solutions down to the low temperatures present in the upper troposphere.

A two step Bayesian approach for genomic prediction of breeding values.

PubMed

Shariati, Mohammad M; Sørensen, Peter; Janss, Luc

2012-05-21

In genomic models that assign an individual variance to each marker, the contribution of one marker to the posterior distribution of the marker variance is only one degree of freedom (df), which introduces many variance parameters with only little information per variance parameter. A better alternative could be to form clusters of markers with similar effects where markers in a cluster have a common variance. Therefore, the influence of each marker group of size p on the posterior distribution of the marker variances will be p df. The simulated data from the 15th QTL-MAS workshop were analyzed such that SNP markers were ranked based on their effects and markers with similar estimated effects were grouped together. In step 1, all markers with minor allele frequency more than 0.01 were included in a SNP-BLUP prediction model. In step 2, markers were ranked based on their estimated variance on the trait in step 1 and each 150 markers were assigned to one group with a common variance. In further analyses, subsets of 1500 and 450 markers with largest effects in step 2 were kept in the prediction model. Grouping markers outperformed SNP-BLUP model in terms of accuracy of predicted breeding values. However, the accuracies of predicted breeding values were lower than Bayesian methods with marker specific variances. Grouping markers is less flexible than allowing each marker to have a specific marker variance but, by grouping, the power to estimate marker variances increases. A prior knowledge of the genetic architecture of the trait is necessary for clustering markers and appropriate prior parameterization.

Exposing earth surface process model simulations to a large audience

NASA Astrophysics Data System (ADS)

Overeem, I.; Kettner, A. J.; Borkowski, L.; Russell, E. L.; Peddicord, H.

2015-12-01

The Community Surface Dynamics Modeling System (CSDMS) represents a diverse group of >1300 scientists who develop and apply numerical models to better understand the Earth's surface. CSDMS has a mandate to make the public more aware of model capabilities and therefore started sharing state-of-the-art surface process modeling results with large audiences. One platform to reach audiences outside the science community is through museum displays on 'Science on a Sphere' (SOS). Developed by NOAA, SOS is a giant globe, linked with computers and multiple projectors and can display data and animations on a sphere. CSDMS has developed and contributed model simulation datasets for the SOS system since 2014, including hydrological processes, coastal processes, and human interactions with the environment. Model simulations of a hydrological and sediment transport model (WBM-SED) illustrate global river discharge patterns. WAVEWATCH III simulations have been specifically processed to show the impacts of hurricanes on ocean waves, with focus on hurricane Katrina and super storm Sandy. A large world dataset of dams built over the last two centuries gives an impression of the profound influence of humans on water management. Given the exposure of SOS, CSDMS aims to contribute at least 2 model datasets a year, and will soon provide displays of global river sediment fluxes and changes of the sea ice free season along the Arctic coast. Over 100 facilities worldwide show these numerical model displays to an estimated 33 million people every year. Datasets storyboards, and teacher follow-up materials associated with the simulations, are developed to address common core science K-12 standards. CSDMS dataset documentation aims to make people aware of the fact that they look at numerical model results, that underlying models have inherent assumptions and simplifications, and that limitations are known. CSDMS contributions aim to familiarize large audiences with the use of numerical modeling as a tool to create understanding of environmental processes.

The contributions of admixture and genetic drift to diversity among post-contact populations in the Americas.

PubMed

Koehl, Anthony J; Long, Jeffrey C

2018-02-01

We present a model that partitions Nei's minimum genetic distance between admixed populations into components of admixture and genetic drift. We applied this model to 17 admixed populations in the Americas to examine how admixture and drift have contributed to the patterns of genetic diversity. We analyzed 618 short tandem repeat loci in 949 individuals from 49 population samples. Thirty-two samples serve as proxies for continental ancestors. Seventeen samples represent admixed populations: (4) African-American and (13) Latin American. We partition genetic distance, and then calculate fixation indices and principal coordinates to interpret our results. A computer simulation confirms that our method correctly estimates drift and admixture components of genetic distance when the assumptions of the model are met. The partition of genetic distance shows that both admixture and genetic drift contribute to patterns of genetic diversity. The admixture component of genetic distance provides evidence for two distinct axes of continental ancestry. However, the genetic distances show that ancestry contributes to only one axis of genetic differentiation. The genetic distances among the 13 Latin American populations in this analysis show contributions from both differences in ancestry and differences in genetic drift. By contrast, the genetic distances among the four African American populations in this analysis owe mostly to genetic drift because these groups have similar fractions of European and African ancestry. The genetic structure of admixed populations in the Americas reflects more than admixture. We show that the history of serial founder effects constrains the impact of admixture on allele frequencies to a single dimension. Genetic drift in the admixed populations imposed a new level of genetic structure onto that created by admixture. © 2017 Wiley Periodicals, Inc.

A Group Contribution Method for Estimating Cetane and Octane Numbers

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

Kubic, William Louis

Much of the research on advanced biofuels is devoted to the study of novel chemical pathways for converting nonfood biomass into liquid fuels that can be blended with existing transportation fuels. Many compounds under consideration are not found in the existing fuel supplies. Often, the physical properties needed to assess the viability of a potential biofuel are not available. The only reliable information available may be the molecular structure. Group contribution methods for estimating physical properties from molecular structure have been used for more than 60 years. The most common application is estimation of thermodynamic properties. More recently, group contributionmore » methods have been developed for estimating rate dependent properties including cetane and octane numbers. Often, published group contribution methods are limited in terms of types of function groups and range of applicability. In this study, a new, broadly-applicable group contribution method based on an artificial neural network was developed to estimate cetane number research octane number, and motor octane numbers of hydrocarbons and oxygenated hydrocarbons. The new method is more accurate over a greater range molecular weights and structural complexity than existing group contribution methods for estimating cetane and octane numbers.« less

Peer-Assessing Peers' Contribution to EFL Group Presentations

ERIC Educational Resources Information Center

Saito, Hidetoshi; Fujita, Tomoko

2009-01-01

The aim of this study is three-fold: (1) to examine the similarities and differences between instructor and peer assessments of EFL group presentations; (2) to understand the utility of peer assessment for discriminating each group member's contribution to group presentations in college EFL classrooms; and (3) to investigate the relationship…

Commentary on the MID3 Good Practices Paper.

PubMed

Manolis, Efthymios; Brogren, Jacob; Cole, Susan; Hay, Justin L; Nordmark, Anna; Karlsson, Kristin E; Lentz, Frederike; Benda, Norbert; Wangorsch, Gaby; Pons, Gerard; Zhao, Wei; Gigante, Valeria; Serone, Francesca; Standing, Joseph F; Dokoumetzidis, Aris; Vakkilainen, Juha; van den Heuvel, Michiel; Mangas Sanjuan, Victor; Taminiau, Johannes; Kerwash, Essam; Khan, David; Musuamba, Flora Tshinanu; Skottheim Rusten, Ine

2017-07-01

During the last 10 years the European Medicines Agency (EMA) organized a number of workshops on modeling and simulation, working towards greater integration of modeling and simulation (M&S) in the development and regulatory assessment of medicines. In the 2011 EMA - European Federation of Pharmaceutical Industries and Associations (EFPIA) Workshop on Modelling and Simulation, European regulators agreed to the necessity to build expertise to be able to review M&S data provided by companies in their dossier. This led to the establishment of the EMA Modelling and Simulation Working Group (MSWG). Also, there was agreement reached on the need for harmonization on good M&S practices and for continuing dialog across all parties. The MSWG acknowledges the initiative of the EFPIA Model-Informed Drug Discovery and Development (MID3) group in promoting greater consistency in practice, application, and documentation of M&S and considers the paper is an important contribution towards achieving this objective. © 2017 The Authors CPT: Pharmacometrics & Systems Pharmacology published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.

Estimates of the relative and absolute diurnal contributions of fasting and post-prandial plasma glucose over a range of hyperglycaemia in type 2 diabetes.

PubMed

Peter, R; Dunseath, G; Luzio, S D; Owens, D R

2013-09-01

To re-examine the relative and absolute contributions of fasting/pre-prandial glucose (FPG) and post-prandial glucose (PPG) to 24-h hyperglycaemia and HbA1c respectively in non-insulin treated subjects with type 2 diabetes (T2DM). A total of 52 T2DM subjects (37 men) had daytime 12h plasma glucose (PG) profiles determined in response to three serial identical test meals commencing at 08 00h with pre-prandial and frequent post-prandial blood samples collected. The overnight PG profile was derived by projecting the 20 00h glucose concentration to the pre-breakfast value at 08 00h. PPG exposure was calculated above fasting/pre-prandial value for each meal. Excess hyperglycaemia was calculated based on a PG>5.5mmol/L with fasting hyperglycaemia being the difference between the two measurements. The subjects were divided into five groups according to the HbA1c (Group 1<7.0%; Group 2: 7.0-<7.5; Group 3: 7.5-<8.0%; Group 4: 8.0-<9.0%; Group 5:≥9.0%). The 24h relative contribution of PPG exposure and fasting hyperglycaemia to excess hyperglycaemia and the absolute contribution of PPG and fasting hyperglycaemia to excess HbA1c (HbA1c - 5.1%) was calculated. With deteriorating glycaemia, the relative contribution of PPG exposure decreased across the groups from 43.5% (HbA1c<7.0%) to 17.8% (HbA1c≥9.0%), whilst the contributions of fasting hyperglycaemia increased from 56.5% to 82.2% (P=0.004), respectively. The absolute contributions of PPG to excess HbA1c was 0.7%, which remained relatively stable across the spectrum of HbA1c, whilst fasting hyperglycaemia increased significantly from groups 1 to 5 (P<0.001). Fasting hyperglycaemia contributes substantially in all groups, increasing as HbA1c deteriorates. The absolute contribution of PPG to excess HbA1c did not vary across the range of HbA1c, representing a significant relative contribution even in well-controlled subjects with a HbA1c<7.0%. Copyright © 2013. Published by Elsevier Masson SAS.

Mastery motivation as a predictor of occupational performance following upper limb intervention for school-aged children with congenital hemiplegia.

PubMed

Miller, Laura; Ziviani, Jenny; Ware, Robert S; Boyd, Roslyn N

2014-10-01

To determine the extent to which children's mastery motivation predicts occupational performance outcomes following upper limb intervention (ULI). In this cohort study, participants received 45 hours of ULI, either in an intensive group-based or distributed individualized model. The Dimensions of Mastery Questionnaire (DMQ) measured mastery motivation at baseline. Occupational performance outcomes were assessed at baseline and 13 weeks' post-intervention using the Canadian Occupational Performance Measure (COPM). Multivariable models determined the contribution of mastery motivation to COPM outcome irrespective of group membership. Forty-two children with congenital hemiplegia (29 males, 13 females; mean age 7y 8mo [SD 2y 2mo]; range 5y 1mo-12y 8mo; Manual Ability Classification System [MACS] I=20 and II=22; predominant motor type unilateral spastic n=41) participated in the study. Significant gains were seen in COPM performance and satisfaction scores (p<0.001) post-intervention with no between group differences. Children who had greater persistence with object-oriented tasks (p=0.02) and better manual ability (p=0.03) achieved higher COPM performance scores at 13 weeks. Children's persistence on object-oriented tasks was the strongest predictor of COPM satisfaction (p=0.01). Children's persistence with object-oriented tasks as well as manual abilities needs to be considered when undertaking ULI. Predetermining children's motivational predispositions can assist clinicians to tailor therapy sessions individually based on children's strengths, contributing to effective engagement in ULI. © 2014 Mac Keith Press.

Type 2 Diabetic Rats on Diet Supplemented With Chromium Malate Show Improved Glycometabolism, Glycometabolism-Related Enzyme Levels and Lipid Metabolism

PubMed Central

Feng, Weiwei; Zhao, Ting; Mao, Guanghua; Wang, Wei; Feng, Yun; Li, Fang; Zheng, Daheng; Wu, Huiyu; Jin, Dun; Yang, Liuqing; Wu, Xiangyang

2015-01-01

Our previous study showed that chromium malate improved the regulation of blood glucose in mice with alloxan-induced diabetes. The present study was designed to evaluate the effect of chromium malate on glycometabolism, glycometabolism-related enzymes and lipid metabolism in type 2 diabetic rats. Our results showed that fasting blood glucose, serum insulin level, insulin resistance index and C-peptide level in the high dose group had a significant downward trend when compared with the model group, chromium picolinate group and chromium trichloride group. The hepatic glycogen, glucose-6-phosphate dehydrogenase, glucokinase, Glut4, phosphor-AMPKβ1 and Akt levels in the high dose group were significantly higher than those of the model, chromium picolinate and chromium trichloride groups. Chromium malate in a high dose group can significantly increase high density lipoprotein cholesterol level while decreasing the total cholesterol, low density lipoprotein cholesterol and triglyceride levels when compared with chromium picolinate and chromium trichloride. The serum chromium content in chromium malate and chromium picolinate group is significantly higher than that of the chromium trichloride group. The results indicated that the curative effects of chromium malate on glycometabolism, glycometabolism-related enzymes and lipid metabolism changes are better than those of chromium picolinate and chromium trichloride. Chromium malate contributes to glucose uptake and transport in order to improved glycometabolism and glycometabolism-related enzymes. PMID:25942313

Type 2 diabetic rats on diet supplemented with chromium malate show improved glycometabolism, glycometabolism-related enzyme levels and lipid metabolism.

PubMed

Feng, Weiwei; Zhao, Ting; Mao, Guanghua; Wang, Wei; Feng, Yun; Li, Fang; Zheng, Daheng; Wu, Huiyu; Jin, Dun; Yang, Liuqing; Wu, Xiangyang

2015-01-01

Our previous study showed that chromium malate improved the regulation of blood glucose in mice with alloxan-induced diabetes. The present study was designed to evaluate the effect of chromium malate on glycometabolism, glycometabolism-related enzymes and lipid metabolism in type 2 diabetic rats. Our results showed that fasting blood glucose, serum insulin level, insulin resistance index and C-peptide level in the high dose group had a significant downward trend when compared with the model group, chromium picolinate group and chromium trichloride group. The hepatic glycogen, glucose-6-phosphate dehydrogenase, glucokinase, Glut4, phosphor-AMPKβ1 and Akt levels in the high dose group were significantly higher than those of the model, chromium picolinate and chromium trichloride groups. Chromium malate in a high dose group can significantly increase high density lipoprotein cholesterol level while decreasing the total cholesterol, low density lipoprotein cholesterol and triglyceride levels when compared with chromium picolinate and chromium trichloride. The serum chromium content in chromium malate and chromium picolinate group is significantly higher than that of the chromium trichloride group. The results indicated that the curative effects of chromium malate on glycometabolism, glycometabolism-related enzymes and lipid metabolism changes are better than those of chromium picolinate and chromium trichloride. Chromium malate contributes to glucose uptake and transport in order to improved glycometabolism and glycometabolism-related enzymes.

Thymoquinone Attenuates Brain Injury via an Anti-oxidative Pathway in a Status Epilepticus Rat Model.

PubMed

Shao, Yi-Ye; Li, Bing; Huang, Yong-Mei; Luo, Qiong; Xie, Yang-Mei; Chen, Ying-Hui

2017-01-01

Status epilepticus (SE) results in the generation of reactive oxygen species (ROS), which contribute to seizure-induced brain injury. It is well known that oxidative stress plays a pivotal role in status epilepticus (SE). Thymoquinone (TQ) is a bioactive monomer extracted from black cumin (Nigella sativa) seed oil that has anti-inflammatory, anti-cancer, and antioxidant activity in various diseases. This study evaluated the protective effects of TQ on brain injury in a lithium-pilocarpine rat model of SE and investigated the underlying mechanism related to antioxidative pathway. Electroencephalogram and Racine scale were used to value seizure severity. Passive-avoidance test was used to determine learning and memory function. Moreover, anti-oxidative activity of TQ was observed using Western blot and super oxide dismutase (SOD) activity assay. Latency to SE increased in the TQ-pretreated group compared with rats in the model group, while the total power was significantly lower. Seizure severity measured on the Racine scale was significantly lower in the TQ group compared with the model group. Results of behavioral experiments suggest that TQ may also have a protective effect on learning and memory function. Investigation of the protective mechanism of TQ showed that TQ-pretreatment significantly increased the expression of Nrf2, HO-1 proteins and SOD in the hippocampus. These findings showed that TQ attenuated brain injury induced by SE via an anti-oxidative pathway.

A statistical model to estimate the impact of a hepatitis A vaccination programme.

PubMed

Oviedo, Manuel; Pilar Muñoz, M; Domínguez, Angela; Borras, Eva; Carmona, Gloria

2008-11-11

A program of routine hepatitis A+B vaccination in preadolescents was introduced in 1998 in Catalonia, a region situated in the northeast of Spain. The objective of this study was to quantify the reduction in the incidence of hepatitis A in order to differentiate the natural reduction of the incidence of hepatitis A from that produced due to the vaccination programme and to predict the evolution of the disease in forthcoming years. A generalized linear model (GLM) using negative binomial regression was used to estimate the incidence rates of hepatitis A in Catalonia by year, age group and vaccination. Introduction of the vaccine reduced cases by 5.5 by year (p-value<0.001), but there was a significant interaction between the year of report and vaccination that smoothed this reduction (p-value<0.001). The reduction was not equal in all age groups, being greater in the 12-18 years age group, which fell from a mean rate of 8.15 per 100,000 person/years in the pre-vaccination period (1992-1998) to 1.4 in the vaccination period (1999-2005). The model predicts the evolution accurately for the group of vaccinated subjects. Negative binomial regression is more appropriate than Poisson regression when observed variance exceeds the observed mean (overdispersed count data), can cause a variable apparently contribute more on the model of what really makes it.

How Can Intergroup Interaction Be Bad If Intergroup Contact Is Good? Exploring and Reconciling an Apparent Paradox in the Science of Intergroup Relations

PubMed Central

Page-Gould, Elizabeth

2015-01-01

The outcomes of social interactions among members of different groups (e.g., racial groups, political groups, sexual orientation groups) have long been of interest to psychologists. Two related literatures on the topic have emerged—the intergroup interaction literature and the intergroup contact literature—in which divergent conclusions have been reported. Intergroup interaction is typically found to have negative effects tied to intergroup bias, producing heightened stress, intergroup anxiety, or outgroup avoidance, whereas intergroup contact is typically found to have positive effects tied to intergroup bias, predicting lower intergroup anxiety and lower prejudice. We examine these paradoxical findings, proposing that researchers contributing to the two literatures are examining different levels of the same phenomenon and that methodological differences can account for the divide between the literatures. Further, we introduce a mathematical model by which the findings of the two literatures can be reconciled. We believe that adopting this model will streamline thinking in the field and will generate integrative new research in which investigators examine how a person’s experiences with diversity unfold. PMID:25987510

Renormalization group fixed points of foliated gravity-matter systems

NASA Astrophysics Data System (ADS)

Biemans, Jorn; Platania, Alessia; Saueressig, Frank

2017-05-01

We employ the Arnowitt-Deser-Misner formalism to study the renormalization group flow of gravity minimally coupled to an arbitrary number of scalar, vector, and Dirac fields. The decomposition of the gravitational degrees of freedom into a lapse function, shift vector, and spatial metric equips spacetime with a preferred (Euclidean) "time"- direction. In this work, we provide a detailed derivation of the renormalization group flow of Newton's constant and the cosmological constant on a flat Friedmann-Robertson-Walker background. Adding matter fields, it is shown that their contribution to the flow is the same as in the covariant formulation and can be captured by two parameters d g d λ . We classify the resulting fixed point structure as a function of these parameters finding that the existence of non-Gaussian renormalization group fixed points is rather generic. In particular the matter content of the standard model and its most common extensions gives rise to one non-Gaussian fixed point with real critical exponents suitable for Asymptotic Safety. Moreover, we find non-Gaussian fixed points for any number of scalar matter fields, making the scenario attractive for cosmological model building.

Metals sorption from aqueous solutions by Kluyveromyces marxianus: process optimization, equilibrium modeling and chemical characterization.

PubMed

Pal, Rama; Tewari, Saumyata; Rai, Jai P N

2009-10-01

The dead Kluyveromyces marxianus biomass, a fermentation industry waste, was used to explore its sorption potential for lead, mercury, arsenic, cobalt, and cadmium as a function of pH, biosorbent dosage, contact time, agitation speed, and initial metal concentration. The equilibrium data fitted the Langmuir model better for cobalt and cadmium, but Freundlich isotherm for all metals tested. At equilibrium, the maximum uptake capacity (Qmax) was highest for lead followed by mercury, arsenic, cobalt, and cadmium. The RL values ranged between 0-1, indicating favorable sorption of all test metals by the biosorbent. The maximum Kf value of Pb showed its efficient removal from the solution. However, multi-metal analysis depicted that sorption of all metals decreased except Pb. The potentiometric titration of biosorbent revealed the presence of functional groups viz. amines, carboxylic acids, phosphates, and sulfhydryl group involved in heavy metal sorption. The extent of contribution of functional groups and lipids to biosorption was in the order: carboxylic>lipids>amines>phosphates. Blocking of sulfhydryl group did not have any significant effect on metal sorption.

The contribution of smoking to socioeconomic differentials in mortality: results from the Melbourne Collaborative Cohort Study, Australia

PubMed Central

Siahpush, Mohammad; English, Dallas; Powles, John

2006-01-01

Objective To assess the contribution of smoking to the inverse association of mortality with years of formal education in men in Australia. Design Data were obtained from a prospective cohort study that included 17 049 men in Melbourne recruited from 1990 to 1994, most of whom were aged between 40 and 69 years at baseline. The outcome measured was all‐cause mortality. The contribution of smoking to socioeconomic status differentials was estimated by including smoking as a variable in a Cox's proportional hazards model that also included education and other potential confounding variables. Results In men, the association between education and mortality was attenuated after adjustment for smoking, and the aetiological fraction for low levels of education was reduced from 16.5% to 10.6%. Conclusions In men, smoking contributes substantially to socioeconomic differentials in mortality. Effective policies and interventions that target smoking among socially disadvantaged groups may substantially reduce socioeconomic differentials in health. PMID:17108305

Self-organised criticality in the evolution of a thermodynamic model of rodent thermoregulatory huddling

PubMed Central

2017-01-01

A thermodynamic model of thermoregulatory huddling interactions between endotherms is developed. The model is presented as a Monte Carlo algorithm in which animals are iteratively exchanged between groups, with a probability of exchanging groups defined in terms of the temperature of the environment and the body temperatures of the animals. The temperature-dependent exchange of animals between groups is shown to reproduce a second-order critical phase transition, i.e., a smooth switch to huddling when the environment gets colder, as measured in recent experiments. A peak in the rate at which group sizes change, referred to as pup flow, is predicted at the critical temperature of the phase transition, consistent with a thermodynamic description of huddling, and with a description of the huddle as a self-organising system. The model was subjected to a simple evolutionary procedure, by iteratively substituting the physiologies of individuals that fail to balance the costs of thermoregulation (by huddling in groups) with the costs of thermogenesis (by contributing heat). The resulting tension between cooperative and competitive interactions was found to generate a phenomenon called self-organised criticality, as evidenced by the emergence of avalanches in fitness that propagate across many generations. The emergence of avalanches reveals how huddling can introduce correlations in fitness between individuals and thereby constrain evolutionary dynamics. Finally, a full agent-based model of huddling interactions is also shown to generate criticality when subjected to the same evolutionary pressures. The agent-based model is related to the Monte Carlo model in the way that a Vicsek model is related to an Ising model in statistical physics. Huddling therefore presents an opportunity to use thermodynamic theory to study an emergent adaptive animal behaviour. In more general terms, huddling is proposed as an ideal system for investigating the interaction between self-organisation and natural selection empirically. PMID:28141809

Stimulating Contributions to Public Goods through Information Feedback: Some Experimental Results

PubMed Central

Janssen, Marco A.; Lee, Allen; Sundaram, Hari

2016-01-01

In traditional public good experiments participants receive an endowment from the experimenter that can be invested in a public good or kept in a private account. In this paper we present an experimental environment where participants can invest time during five days to contribute to a public good. Participants can make contributions to a linear public good by logging into a web application and performing virtual actions. We compared four treatments, with different group sizes and information of (relative) performance of other groups. We find that information feedback about performance of other groups has a small positive effect if we control for various attributes of the groups. Moreover, we find a significant effect of the contributions of others in the group in the previous day on the number of points earned in the current day. Our results confirm that people participate more when participants in their group participate more, and are influenced by information about the relative performance of other groups. PMID:27459070

A Dynamic Simulation Model of Land-Use, Population, and Rural Livelihoods in the Central Rift Valley of Ethiopia

NASA Astrophysics Data System (ADS)

Garedew, Efrem; Sandewall, Mats; Soderberg, Ulf

2012-01-01

The dynamic interactions between society and land resources have to be taken into account when planning and managing natural resources. A computer model, using STELLA software, was developed through active participation of purposively selected farm households from different wealth groups, age groups and gender within a rural community and some members of Kebelle council. The aim of the modeling was to study the perceived changes in land-use, population and livelihoods over the next 30 years and to improve our understanding of the interactions among them. The modeling output is characterized by rapid population growth, declining farm size and household incomes, deteriorating woody vegetation cover and worsening land degradation if current conditions remain. However, through integrated intervention strategies (including forest increase, micro-finance, family planning, health and education) the woody vegetation cover is likely to increase in the landscape, population growth is likely to slow down and households' income is likely to improve. A validation assessment of the simulation model based on historical data on land-use and population from 1973 to 2006 showed that the model is relatively robust. We conclude that as a supporting tool, the simulation model can contribute to the decision making process.

An Analytical Approach for Relating Boiling Points of Monofunctional Organic Compounds to Intermolecular Forces

ERIC Educational Resources Information Center

Struyf, Jef

2011-01-01

The boiling point of a monofunctional organic compound is expressed as the sum of two parts: a contribution to the boiling point due to the R group and a contribution due to the functional group. The boiling point in absolute temperature of the corresponding RH hydrocarbon is chosen for the contribution to the boiling point of the R group and is a…

Understanding Elementary Astronomy by Making Drawing-Based Models

NASA Astrophysics Data System (ADS)

van Joolingen, W. R.; Aukes, Annika V. A.; Gijlers, H.; Bollen, L.

2015-04-01

Modeling is an important approach in the teaching and learning of science. In this study, we attempt to bring modeling within the reach of young children by creating the SimSketch modeling system, which is based on freehand drawings that can be turned into simulations. This system was used by 247 children (ages ranging from 7 to 15) to create a drawing-based model of the solar system. The results show that children in the target age group are capable of creating a drawing-based model of the solar system and can use it to show the situations in which eclipses occur. Structural equation modeling predicting post-test knowledge scores based on learners' pre-test knowledge scores, the quality of their drawings and motivational aspects yielded some evidence that such drawing contributes to learning. Consequences for using modeling with young children are considered.

Health-Related Quality of Life, Self-Efficacy and Enjoyment Keep the Socially Vulnerable Physically Active in Community-Based Physical Activity Programs: A Sequential Cohort Study

PubMed Central

Herens, Marion; Bakker, Evert Jan; van Ophem, Johan; Wagemakers, Annemarie; Koelen, Maria

2016-01-01

Physical inactivity is most commonly found in socially vulnerable groups. Dutch policies target these groups through community-based health-enhancing physical activity (CBHEPA) programs. As robust evidence on the effectiveness of this approach is limited, this study investigated whether CBHEPA programs contribute to an increase in and the maintenance of physical activity in socially vulnerable groups. In four successive cohorts, starting at a six-month interval, 268 participants from 19 groups were monitored for twelve months in seven CBHEPA programs. Data collection was based on repeated questionnaires. Socio-economic indicators, program participation and coping ability were measured at baseline. Physical activity, health-related quality of life and on-going program participation were measured three times. Self-efficacy and enjoyment were measured at baseline and at twelve months. Statistical analyses were based on a quasi-RCT design (independent t-tests), a comparison of participants and dropouts (Mann-Whitney test), and multilevel modelling to assess change in individual physical activity, including group level characteristics. Participants of CBHEPA programs are socially vulnerable in terms of low education (48.6%), low income (52.4%), non-Dutch origin (64.6%) and health-related quality of life outcomes. Physical activity levels were not below the Dutch average. No increase in physical activity levels over time was observed. The multilevel models showed significant positive associations between health-related quality of life, self-efficacy and enjoyment, and leisure-time physical activity over time. Short CBHEPA programs (10–13 weeks) with multiple trainers and gender-homogeneous groups were associated with lower physical activity levels over time. At twelve months, dropouts' leisure-time physical activity levels were significantly lower compared to continuing participants, as were health-related quality of life, self-efficacy and enjoyment outcomes. BMI and care consumption scored significantly higher among dropouts. In conclusion, Dutch CBHEPA programs reach socially vulnerable, but not necessarily inactive, groups in terms of socio-economic and health-related quality of life outcomes. Our findings suggest that CBHEPA programs particularly contribute to physical activity maintenance in socially vulnerable groups, rather than to an increase in physical activity behaviour over time. PMID:26909696

Health-Related Quality of Life, Self-Efficacy and Enjoyment Keep the Socially Vulnerable Physically Active in Community-Based Physical Activity Programs: A Sequential Cohort Study.

PubMed

Herens, Marion; Bakker, Evert Jan; van Ophem, Johan; Wagemakers, Annemarie; Koelen, Maria

2016-01-01

Physical inactivity is most commonly found in socially vulnerable groups. Dutch policies target these groups through community-based health-enhancing physical activity (CBHEPA) programs. As robust evidence on the effectiveness of this approach is limited, this study investigated whether CBHEPA programs contribute to an increase in and the maintenance of physical activity in socially vulnerable groups. In four successive cohorts, starting at a six-month interval, 268 participants from 19 groups were monitored for twelve months in seven CBHEPA programs. Data collection was based on repeated questionnaires. Socio-economic indicators, program participation and coping ability were measured at baseline. Physical activity, health-related quality of life and on-going program participation were measured three times. Self-efficacy and enjoyment were measured at baseline and at twelve months. Statistical analyses were based on a quasi-RCT design (independent t-tests), a comparison of participants and dropouts (Mann-Whitney test), and multilevel modelling to assess change in individual physical activity, including group level characteristics. Participants of CBHEPA programs are socially vulnerable in terms of low education (48.6%), low income (52.4%), non-Dutch origin (64.6%) and health-related quality of life outcomes. Physical activity levels were not below the Dutch average. No increase in physical activity levels over time was observed. The multilevel models showed significant positive associations between health-related quality of life, self-efficacy and enjoyment, and leisure-time physical activity over time. Short CBHEPA programs (10-13 weeks) with multiple trainers and gender-homogeneous groups were associated with lower physical activity levels over time. At twelve months, dropouts' leisure-time physical activity levels were significantly lower compared to continuing participants, as were health-related quality of life, self-efficacy and enjoyment outcomes. BMI and care consumption scored significantly higher among dropouts. In conclusion, Dutch CBHEPA programs reach socially vulnerable, but not necessarily inactive, groups in terms of socio-economic and health-related quality of life outcomes. Our findings suggest that CBHEPA programs particularly contribute to physical activity maintenance in socially vulnerable groups, rather than to an increase in physical activity behaviour over time.

Statistical Analysis of the Impacts of Regional Transportation on the Air Quality in Beijing

NASA Astrophysics Data System (ADS)

Huang, Zhongwen; Zhang, Huiling; Tong, Lei; Xiao, Hang

2016-04-01

From October to December 2015, Beijing-Tianjin-Hebei (BTH) region had experienced several severe haze events. In order to assess the effects of the regional transportation on the air quality in Beijing, the air monitoring data (PM2.5, SO2, NO2 and CO) from that period published by Chinese National Environmental Monitoring Center (CNEMC) was collected and analyzed with various statistical models. The cities within BTH area were clustered into three groups according to the geographical conditions, while the air pollutant concentrations of cities within a group sharing similar variation trends. The Granger causality test results indicate that significant causal relationships exist between the air pollutant data of Beijing and its surrounding cities (Baoding, Chengde, Tianjin and Zhangjiakou) for the reference period. Then, linear regression models were constructed to capture the interdependency among the multiple time series. It shows that the observed air pollutant concentrations in Beijing were well consistent with the model-fitted results. More importantly, further analysis suggests that the air pollutants in Beijing were strongly affected by regional transportation, as the local sources only contributed 17.88%, 27.12%, 14.63% and 31.36% of PM2.5, SO2, NO2 and CO concentrations, respectively. And the major foreign source for Beijing was from Southwest (Baoding) direction, account for more than 42% of all these air pollutants. Thus, by combining various statistical models, it may not only be able to quickly predict the air qualities of any cities on a regional scale, but also to evaluate the local and regional source contributions for a particular city. Key words: regional transportation, air pollution, Granger causality test, statistical models

Road to better health and integration: a Delphi study on health service models for Hong Kong migrants.

PubMed

Wong, William C W; Ho, Petula S Y; Liang, Jun; Holroyd, Eleanor A; Lam, Cindy L K; Pau, Agnes M Y

2014-12-19

In Hong Kong, migrants arriving from Mainland China often have multiple roles and responsibilities while adapting to new lives in their host destination. This paper explored the factors that contribute to the inequity in health services utilisation experienced by these migrants; and, identified the elements that could constitute an effective health delivery model to address the service gap. Site visits and a focus group discussion (n = 13) were held with both public and private health providers before a number of innovative health delivery models were formulated. They were then circulated among the panel in two further rounds of Delphi survey (n = 11) from March-April 2012 to systematically collect opinions and select the most endorsed health service models to serve this target population. Focus group members perceived that most migrants were unaware of, or even ignored, their own physical and mental health needs, and had low utilisation of healthcare services, because of their pre-occupation with daily chores and hardship as well as differing health values, practices and expectations. They further identified that the structural issues such as the healthcare setting or the operation of current service provisions had failed to meet migrants' health needs. Consequently, four new service models that incorporated professional advice and empowerment, which were identified as the two most important elements, were put forward. Thus, the model of having a nurse with social work training, supported by volunteer groups, was selected as the best option to familiarise and empower patients within the labyrinth of local healthcare services. Implementation of a social empowerment model by way of targeted support and specific health information is recommended. Further evaluation of this model is needed to understand its effectiveness for improving health literacy and health status in this disadvantaged group in the long term.

Plausible role for CHW peer support groups in increasing care-seeking in an integrated community case management project in Rwanda: a mixed methods evaluation

PubMed Central

Langston, Anne; Weiss, Jennifer; Landegger, Justine; Pullum, Thomas; Morrow, Melanie; Kabadege, Melene; Mugeni, Catherine; Sarriot, Eric

2014-01-01

ABSTRACT Background: The Kabeho Mwana project (2006–2011) supported the Rwanda Ministry of Health (MOH) in scaling up integrated community case management (iCCM) of childhood illness in 6 of Rwanda's 30 districts. The project trained and equipped community health workers (CHWs) according to national guidelines. In project districts, Kabeho Mwana staff also trained CHWs to conduct household-level health promotion and established supervision and reporting mechanisms through CHW peer support groups (PSGs) and quality improvement systems. Methods: The 2005 and 2010 Demographic and Health Surveys were re-analyzed to evaluate how project and non-project districts differed in terms of care-seeking for fever, diarrhea, and acute respiratory infection symptoms and related indicators. We developed a logit regression model, controlling for the timing of the first CHW training, with the district included as a fixed categorical effect. We also analyzed qualitative data from the final evaluation to examine factors that may have contributed to improved outcomes. Results: While there was notable improvement in care-seeking across all districts, care-seeking from any provider for each of the 3 conditions, and for all 3 combined, increased significantly more in the project districts. CHWs contributed a larger percentage of consultations in project districts (27%) than in non-project districts (12%). Qualitative data suggested that the PSG model was a valuable sub-level of CHW organization associated with improved CHW performance, supervision, and social capital. Conclusions: The iCCM model implemented by Kabeho Mwana resulted in greater improvements in care-seeking than those seen in the rest of the country. Intensive monitoring, collaborative supervision, community mobilization, and CHW PSGs contributed to this success. The PSGs were a unique contribution of the project, playing a critical role in improving care-seeking in project districts. Effective implementation of iCCM should therefore include CHW management and social support mechanisms. Finally, re-analysis of national survey data improved evaluation findings by providing impact estimates. PMID:25276593

Validation of Donor-Specific Tolerance of Intestinal Transplant by a Secondary Heart Transplantation Model.

PubMed

Pengcheng, Wang; Xiaosong, Li; Xiaofeng, Li; Zhongzhi, Li

2017-02-01

It is well accepted that survival after a second organ transplant without immunosuppressive agents indicates tolerance for the first transplant. To validate donor-specific tolerance, we established a rat model with a secondary heart transplant after intestinal transplant, which has so far not been described in the literature. We transplanted intestine from Fischer F344 rats to Lewis rats orthotopically. Lewis rats received tacrolimus pretreatment before transplant and a 14-day course of rapamycin 1 month after transplant. At 120 days after primary intestinal transplant, hearts from 6 F344 rats (group A) or 6 Brown Norway rats (group B) were transplanted to Lewis rats that had survived intestinal transplant and without additional immunosuppressive agents. We analyzed survival data, histologic changes, cells positive for the ED1 macrophage marker in transplanted hearts, and 3 lymphocyte levels in both groups. Thirty days after secondary heart transplant, group A hearts were continuously beating; however, group B hearts stopped beating at around 10 days after transplant (8.5 ± 1.5 d; P < .05). Our histologic study showed that both groups had muscle damage and cellular infiltration in hearts that were distinctly different from normal hearts, with ED1-positive cells counted in both groups (85 ± 16 in group A, 116 ± 28 in group B; P > .05). Fluorescence-activated cell sorting showed that CD4/CD25-positive regulatory T cell, CTLA4/CD4/CD25-positive regulatory T cell, and Natural killer T-cell levels were significantly higher level in group A versus B (P < .05). The donor-specific tolerance that we observed was possibly a state of "clinical tolerance" rather than "immunologic tolerance." Our rat model is a feasible and reliable model to study donor-specific tolerance. The higher levels of lymphocytic T cells shown in intestinal transplant recipients were associated with longer allograft survival, possibly contributing to donor-specific tolerance.

Contributions of the Histidine Side Chain and the N-terminal α-Amino Group to the Binding Thermodynamics of Oligopeptides to Nucleic Acids as a Function of pH

PubMed Central

Ballin, Jeff D.; Prevas, James P.; Ross, Christina R.; Toth, Eric A.; Wilson, Gerald M.; Record, M. Thomas

2010-01-01

Interactions of histidine with nucleic acid phosphates and histidine pKa shifts make important contributions to many protein-nucleic acid binding processes. To characterize these phenomena in simplified systems, we quantified binding of a histidine-containing model peptide HWKK (+NH3-His-Trp-Lys-Lys-NH2) and its lysine analog KWKK (+NH3-Lys-Trp-Lys-Lys-NH2) to a single-stranded RNA model, polyuridylate (polyU), by changes in tryptophan fluorescence as a function of salt concentration and pH. For both HWKK and KWKK, equilibrium binding constants, Kobs, and magnitudes of log-log salt derivatives SKobs ≡ (∂logKobs/∂log[Na+]), decreased with increasing pH in the manner expected for a titration curve model in which deprotonation of the histidine and α-amino groups weakens binding and reduces its salt-dependence. Fully protonated HWKK and KWKK exhibit the same Kobs and SKobs within uncertainty, and these SKobs values are consistent with limiting-law polyelectrolyte theory for +4 cationic oligopeptides binding to single-stranded nucleic acids. The pH-dependence of HWKK binding to polyU provides no evidence for pKa shifts nor any requirement for histidine protonation, in stark contrast to the thermodynamics of coupled protonation often seen for these cationic residues in the context of native protein structure where histidine protonation satisfies specific interactions (e.g., salt-bridge formation) within highly complementary binding interfaces. The absence of pKa shifts in our studies indicates that additional Coulombic interactions across the nonspecific-binding interface between RNA and protonated histidine or the α-amino group are not sufficient to promote proton uptake for these oligopeptides. We present our findings in the context of hydration models for specific versus nonspecific nucleic acid binding. PMID:20108951

Factors Affecting Loss of Tympanic Membrane Mobility in Acute Otitis Media Model of Chinchilla

PubMed Central

Guan, Xiying; Chen, Yongzheng; Gan, Rong Z.

2014-01-01

Recently we reported that middle ear pressure (MEP), middle ear effusion (MEE), and ossicular changes each contribute to the loss of tympanic membrane (TM) mobility in a guinea pig model of acute otitis media (AOM) induced by S. pneumoniae (Guan and Gan, 2013). However, it is not clear how those factors vary along the course of the disease and whether those effects are reproducible in different species. In this study, a chinchilla AOM model was produced by transbullar injection of Haemophilus influenzae. Mobility of the TM at the umbo was measured by laser vibrometry in two treatment groups: 4 days (4D) and 8 days (8D) post inoculation. These time points represent relatively early and later phases of AOM. In each group, the vibration of the umbo was measured at three experimental stages: unopened, pressure-released, and effusion-removed ears. The effects of MEP and MEE and middle ear structural changes were quantified in each group by comparing the TM mobility at one stage with that of the previous stage. Our findings show that the factors affecting TM mobility do change with the disease time course. The MEP was the dominant contributor to reduction of TM mobility in 4D AOM ears, but showed little effect in 8D ears when MEE filled the tympanic cavity. MEE was the primary factor affecting TM mobility loss in 8D ears, but affected the 4D ears only at high frequencies. After the release of MEP and removal of MEE, residual loss of TM mobility was seen mainly at low frequencies in both 4D and 8D ears, and was associated with middle ear structural changes. Our findings establish that the factors contributing to TM mobility loss in the chinchilla ear were similar to those we reported previously for the guinea pig ears with AOM. Outcomes did not appear to differ between the two major bacterial species causing AOM in these animal models. PMID:24406734

Two-halo term in stacked thermal Sunyaev-Zel'dovich measurements: Implications for self-similarity

NASA Astrophysics Data System (ADS)

Hill, J. Colin; Baxter, Eric J.; Lidz, Adam; Greco, Johnny P.; Jain, Bhuvnesh

2018-04-01

The relation between the mass and integrated electron pressure of galaxy group and cluster halos can be probed by stacking maps of the thermal Sunyaev-Zel'dovich (tSZ) effect. Perhaps surprisingly, recent observational results have indicated that the scaling relation between integrated pressure and mass follows the prediction of simple, self-similar models down to halo masses as low as 1 012.5 M⊙ . Hydrodynamical simulations that incorporate energetic feedback processes suggest that gas should be depleted from such low-mass halos, thus decreasing their tSZ signal relative to self-similar predictions. Here, we build on the modeling of V. Vikram, A. Lidz, and B. Jain, Mon. Not. R. Astron. Soc. 467, 2315 (2017), 10.1093/mnras/stw3311 to evaluate the bias in the interpretation of stacked tSZ measurements due to the signal from correlated halos (the "two-halo" term), which has generally been neglected in the literature. We fit theoretical models to a measurement of the tSZ-galaxy group cross-correlation function, accounting explicitly for the one- and two-halo contributions. We find moderate evidence of a deviation from self-similarity in the pressure-mass relation, even after marginalizing over conservative miscentering effects. We explore pressure-mass models with a break at 1 014 M⊙, as well as other variants. We discuss and test for sources of uncertainty in our analysis, in particular a possible bias in the halo mass estimates and the coarse resolution of the Planck beam. We compare our findings with earlier analyses by exploring the extent to which halo isolation criteria can reduce the two-halo contribution. Finally, we show that ongoing third-generation cosmic microwave background experiments will explicitly resolve the one-halo term in low-mass groups; our methodology can be applied to these upcoming data sets to obtain a clear answer to the question of self-similarity and an improved understanding of hot gas in low-mass halos.

An integrated open framework for thermodynamics of reactions that combines accuracy and coverage.

PubMed

Noor, Elad; Bar-Even, Arren; Flamholz, Avi; Lubling, Yaniv; Davidi, Dan; Milo, Ron

2012-08-01

The laws of thermodynamics describe a direct, quantitative relationship between metabolite concentrations and reaction directionality. Despite great efforts, thermodynamic data suffer from limited coverage, scattered accessibility and non-standard annotations. We present a framework for unifying thermodynamic data from multiple sources and demonstrate two new techniques for extrapolating the Gibbs energies of unmeasured reactions and conditions. Both methods account for changes in cellular conditions (pH, ionic strength, etc.) by using linear regression over the ΔG(○) of pseudoisomers and reactions. The Pseudoisomeric Reactant Contribution method systematically infers compound formation energies using measured K' and pK(a) data. The Pseudoisomeric Group Contribution method extends the group contribution method and achieves a high coverage of unmeasured reactions. We define a continuous index that predicts the reversibility of a reaction under a given physiological concentration range. In the characteristic physiological range 3μM-3mM, we find that roughly half of the reactions in Escherichia coli's metabolism are reversible. These new tools can increase the accuracy of thermodynamic-based models, especially in non-standard pH and ionic strengths. The reversibility index can help modelers decide which reactions are reversible in physiological conditions. Freely available on the web at: http://equilibrator.weizmann.ac.il. Website implemented in Python, MySQL, Apache and Django, with all major browsers supported. The framework is open-source (code.google.com/p/milo-lab), implemented in pure Python and tested mainly on Linux. ron.milo@weizmann.ac.il Supplementary data are available at Bioinformatics online.

An integrated open framework for thermodynamics of reactions that combines accuracy and coverage

PubMed Central

Noor, Elad; Bar-Even, Arren; Flamholz, Avi; Lubling, Yaniv; Davidi, Dan; Milo, Ron

2012-01-01

Motivation: The laws of thermodynamics describe a direct, quantitative relationship between metabolite concentrations and reaction directionality. Despite great efforts, thermodynamic data suffer from limited coverage, scattered accessibility and non-standard annotations. We present a framework for unifying thermodynamic data from multiple sources and demonstrate two new techniques for extrapolating the Gibbs energies of unmeasured reactions and conditions. Results: Both methods account for changes in cellular conditions (pH, ionic strength, etc.) by using linear regression over the ΔG○ of pseudoisomers and reactions. The Pseudoisomeric Reactant Contribution method systematically infers compound formation energies using measured K′ and pKa data. The Pseudoisomeric Group Contribution method extends the group contribution method and achieves a high coverage of unmeasured reactions. We define a continuous index that predicts the reversibility of a reaction under a given physiological concentration range. In the characteristic physiological range 3μM–3mM, we find that roughly half of the reactions in Escherichia coli's metabolism are reversible. These new tools can increase the accuracy of thermodynamic-based models, especially in non-standard pH and ionic strengths. The reversibility index can help modelers decide which reactions are reversible in physiological conditions. Availability: Freely available on the web at: http://equilibrator.weizmann.ac.il. Website implemented in Python, MySQL, Apache and Django, with all major browsers supported. The framework is open-source (code.google.com/p/milo-lab), implemented in pure Python and tested mainly on Linux. Contact: ron.milo@weizmann.ac.il Supplementary Information: Supplementary data are available at Bioinformatics online. PMID:22645166

Chemical and quantum simulation of electron transfer through a polypeptide

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

Ungar, L.W.; Voth, G.A.; Newton, M.D.

1999-08-26

Quantum rate theory, molecular dynamics simulations, and semiempirical electronic structure calculations are used to fully investigate electron transfer mediated by a solvated polypeptide for the first time. Using a stationary-phase approximation, the nonadiabatic electron-transfer rate constant is calculated from the nuclear free energies and the electronic coupling between the initial and final states. The former are obtained from quantum path integral and classical molecular dynamics simulations; the latter are calculated using semiempirical electronic structure calculations and the generalized Mulliken-Hush method. Importantly, no parameters are fit to kinetic data. The simulated system consists of a solvated four-proline polypeptide with a tris(bipyridine)rutheniummore » donor group and an oxypentamminecobalt acceptor group. From the simulation data entropy and energy contributions to the free energies are distinguished. Quantum suppression of the barrier, including important solvent contributions, is demonstrated. Although free energy profiles along the reaction coordinate are nearly parabolic, pronounced departures from harmonic behavior are found for the separate energy and entropy functions. Harmonic models of the system are compared to simulation results in order to quantify anharmonic effects. Electronic structure calculations show that electronic coupling elements vary considerably with system conformation, even when the effective donor-acceptor separation remains roughly constant. The calculations indicate that electron transfer in a significant range of conformations linking the polypeptide to the acceptor may contribute to the overall rate constant. After correction for limitations of the solvent model, the simulations and calculations agree well with the experimental activation energy and Arrhenius prefactor.« less

Combination of inquiry learning model and computer simulation to improve mastery concept and the correlation with critical thinking skills (CTS)

NASA Astrophysics Data System (ADS)

Nugraha, Muhamad Gina; Kaniawati, Ida; Rusdiana, Dadi; Kirana, Kartika Hajar

2016-02-01

Among the purposes of physics learning at high school is to master the physics concepts and cultivate scientific attitude (including critical attitude), develop inductive and deductive reasoning skills. According to Ennis et al., inductive and deductive reasoning skills are part of critical thinking. Based on preliminary studies, both of the competence are lack achieved, it is seen from student learning outcomes is low and learning processes that are not conducive to cultivate critical thinking (teacher-centered learning). One of learning model that predicted can increase mastery concepts and train CTS is inquiry learning model aided computer simulations. In this model, students were given the opportunity to be actively involved in the experiment and also get a good explanation with the computer simulations. From research with randomized control group pretest-posttest design, we found that the inquiry learning model aided computer simulations can significantly improve students' mastery concepts than the conventional (teacher-centered) method. With inquiry learning model aided computer simulations, 20% of students have high CTS, 63.3% were medium and 16.7% were low. CTS greatly contribute to the students' mastery concept with a correlation coefficient of 0.697 and quite contribute to the enhancement mastery concept with a correlation coefficient of 0.603.

Core groups, antimicrobial resistance and rebound in gonorrhoea in North America.

PubMed

Chan, Christina H; McCabe, Caitlin J; Fisman, David N

2012-04-01

Genital tract infections caused by Neisseria gonorrhoeae are a major cause of sexually transmitted disease worldwide. Surveillance data suggest that incidence has increased in recent years after initially falling in the face of intensified control efforts. The authors sought to evaluate the potential contribution of antimicrobial resistance to such rebound and to identify optimal treatment strategies in the face of resistance using a mathematical model of gonorrhoea. The authors built risk-structured 'susceptible-infectious-susceptible' models with and without the possibility of antibiotic resistance and used these models as a platform for the evaluation of competing plausible treatment strategies, including changing antimicrobial choice when resistance prevalence surpassed fixed thresholds, random assignment of treatment and use of combination antimicrobial therapy. Absent antimicrobial resistance, strategies that focus on treatment of highest risk individuals (the so-called core group) result in collapse of disease transmission. When antimicrobial resistance exists, a focus on the core group causes rebound in incidence, with maximal dissemination of antibiotic resistance. Random assignment of antimicrobial treatment class outperformed the use of fixed resistance thresholds with respect to sustained reduction in gonorrhoea prevalence. Gonorrhoea control is achievable only when core groups are treated, but treatment of core groups maximises dissemination of antimicrobial-resistant strains. This paradox poses a great dilemma to the control and prevention of gonorrhoea and underlines the need for gonococcal vaccines.

Triiodothyronine Administration in a Model of Septic Shock: A Randomized Blinded Placebo-Controlled Trial.

PubMed

Maiden, Matthew J; Chapman, Marianne J; Torpy, David J; Kuchel, Timothy R; Clarke, Iain J; Nash, Coralie H; Fraser, Jonathan D; Ludbrook, Guy L

2016-06-01

Triiodothyronine concentration in plasma decreases during septic shock and may contribute to multiple organ dysfunction. We sought to determine the safety and efficacy of administering triiodothyronine, with and without hydrocortisone, in a model of septic shock. Randomized blinded placebo-controlled trial. Preclinical research laboratory. Thirty-two sheep rendered septic with IV Escherichia coli and receiving protocol-guided sedation, ventilation, IV fluids, and norepinephrine infusion. Two hours following induction of sepsis, 32 sheep received a 24-hour IV infusion of 1) placebo + placebo, 2) triiodothyronine + placebo, 3) hydrocortisone + placebo, or 4) triiodothyronine + hydrocortisone. Primary outcome was the total amount of norepinephrine required to maintain a target mean arterial pressure; secondary outcomes included hemodynamic and metabolic indices. Plasma triiodothyronine levels increased to supraphysiological concentrations with hormonal therapy. Following 24 hours of study drug infusion, the amount of norepinephrine required was no different between the study groups (mean ± SD μg/kg; placebo + placebo group 208 ± 392; triiodothyronine + placebo group 501 ± 370; hydrocortisone + placebo group 167 ± 286; triiodothyronine + hydrocortisone group 466 ± 495; p = 0.20). There was no significant treatment effect on any hemodynamic variable, metabolic parameter, or measure of organ function. A 24-hour infusion of triiodothyronine, with or without hydrocortisone, in an ovine model of septic shock did not markedly alter norepinephrine requirement or any other physiological parameter.

I.V. infusion of brain-derived neurotrophic factor gene-modified human mesenchymal stem cells protects against injury in a cerebral ischemia model in adult rat.

PubMed

Nomura, T; Honmou, O; Harada, K; Houkin, K; Hamada, H; Kocsis, J D

2005-01-01

I.V. delivery of mesenchymal stem cells prepared from adult bone marrow reduces infarction size and ameliorates functional deficits in rat cerebral ischemia models. Administration of the brain-derived neurotrophic factor to the infarction site has also been demonstrated to be neuroprotective. To test the hypothesis that brain-derived neurotrophic factor contributes to the therapeutic benefits of mesenchymal stem cell delivery, we compared the efficacy of systemic delivery of human mesenchymal stem cells and human mesenchymal stem cells transfected with a fiber-mutant F/RGD adenovirus vector with a brain-derived neurotrophic factor gene (brain-derived neurotrophic factor-human mesenchymal stem cells). A permanent middle cerebral artery occlusion was induced by intraluminal vascular occlusion with a microfilament. Human mesenchymal stem cells and brain-derived neurotrophic factor-human mesenchymal stem cells were i.v. injected into the rats 6 h after middle cerebral artery occlusion. Lesion size was assessed at 6 h, 1, 3 and 7 days using MR imaging, and histological methods. Functional outcome was assessed using the treadmill stress test. Both human mesenchymal stem cells and brain-derived neurotrophic factor-human mesenchymal stem cells reduced lesion volume and elicited functional improvement compared with the control sham group, but the effect was greater in the brain-derived neurotrophic factor-human mesenchymal stem cell group. ELISA analysis of the infarcted hemisphere revealed an increase in brain-derived neurotrophic factor in the human mesenchymal stem cell groups, but a greater increase in the brain-derived neurotrophic factor-human mesenchymal stem cell group. These data support the hypothesis that brain-derived neurotrophic factor contributes to neuroprotection in cerebral ischemia and cellular delivery of brain-derived neurotrophic factor can be achieved by i.v. delivery of human mesenchymal stem cells.

Cooperation and conflict: field experiments in Northern Ireland.

PubMed

Silva, Antonio S; Mace, Ruth

2014-10-07

The idea that cohesive groups, in which individuals help each other, have a competitive advantage over groups composed of selfish individuals has been widely suggested as an explanation for the evolution of cooperation in humans. Recent theoretical models propose the coevolution of parochial altruism and intergroup conflict, when in-group altruism and out-group hostility contribute to the group's success in these conflicts. However, the few empirical attempts to test this hypothesis do not use natural groups and conflate measures of in-group and unbiased cooperative behaviour. We conducted field experiments based on naturalistic measures of cooperation (school/charity donations and lost letters' returns) with two religious groups with an on-going history of conflict-Catholics and Protestants in Northern Ireland. Conflict was associated with reduced donations to out-group schools and the return of out-group letters, but we found no evidence that it influences in-group cooperation. Rather, socio-economic status was the major determinant of cooperative behaviour. Our study presents a challenge to dominant perspectives on the origins of human cooperation, and has implications for initiatives aiming to promote conflict resolution and social cohesion.

Cooperation and conflict: field experiments in Northern Ireland

PubMed Central

Silva, Antonio S.; Mace, Ruth

2014-01-01

The idea that cohesive groups, in which individuals help each other, have a competitive advantage over groups composed of selfish individuals has been widely suggested as an explanation for the evolution of cooperation in humans. Recent theoretical models propose the coevolution of parochial altruism and intergroup conflict, when in-group altruism and out-group hostility contribute to the group's success in these conflicts. However, the few empirical attempts to test this hypothesis do not use natural groups and conflate measures of in-group and unbiased cooperative behaviour. We conducted field experiments based on naturalistic measures of cooperation (school/charity donations and lost letters' returns) with two religious groups with an on-going history of conflict—Catholics and Protestants in Northern Ireland. Conflict was associated with reduced donations to out-group schools and the return of out-group letters, but we found no evidence that it influences in-group cooperation. Rather, socio-economic status was the major determinant of cooperative behaviour. Our study presents a challenge to dominant perspectives on the origins of human cooperation, and has implications for initiatives aiming to promote conflict resolution and social cohesion. PMID:25143042

Availability, usage and expected contribution of potential nursery habitats for the California halibut

NASA Astrophysics Data System (ADS)

Fodrie, F. Joel; Mendoza, Guillermo

2006-06-01

Coastal ecosystems have been identified as important nursery habitats for many of the world's fishery species. Beyond this, there remain many questions about what exactly constitutes high-value, even critical, habitat for juvenile fish. A first step in investigating nursery habitat value should be to catalogue the spatial coverage (availability) of all potential nursery habitats as well as the distribution (usage) of juvenile fish within those habitats. We conducted two years of fall surveys in the nearshore areas of San Diego County, CA, examining the spatial distribution of 0-group California halibut, Paralichthys californicus. The database generated by 527 otter trawls and block-net seine collections was used to produce a series of models employing regression trees to study the abiotic factors (water column and bottom features) that affect juvenile distributions. Along the exposed coast, highest 0-group densities (0.002-0.008 individuals/m 2 (indiv/m 2)) occurred where temperatures exceeded 21.5 °C (2003), and at depths between 3.3 and 5.2 m (2004). Within protected embayments, densities were higher at depths less than 1.5 m (0.054-0.430 indiv/m 2) and, in 2004, inside channeled marsh estuaries (0.156 indiv/m 2). The spatial coverage of potential nursery habitats was calculated using a Geographic Information System (GIS) database, and the total number of resident 0-group halibut within each site was estimated (habitat area × juvenile halibut density) as a proxy for expected contribution of halibut advancing to the adult stock from each nursery. Although 85% of the potential nursery habitat area occurred along the exposed coastline, 69% (2003) to 58% (2004) of 0-group halibut resided in protected embayments. Embayment contribution is much greater in the southern half of the study region, largely due to Mission and San Diego bays. We conclude that all nursery habitat types demonstrate the potential to contribute significantly to stock fitness, and that in general, shallow and better-protected habitats are highly utilized nurseries for 0-group halibut and deserve special attention in management or conservation efforts.

Designing Groups to Meet Evolving Challenges in Health Care Settings

ERIC Educational Resources Information Center

McCarthy, Christopher J.; Hart, Sonia

2011-01-01

This article provides an overview of the special issue on groups in health care settings and describes how each contribution addresses challenges and opportunities in the health care field for group work. Fundamental criteria for evaluating groups in such settings are applied to each contribution. Finally, trends and opportunities about the future…

Strong-acid, carboxyl-group structures in fulvic acid from the Suwannee River, Georgia. 1. Minor structures

USGS Publications Warehouse

Leenheer, J.A.; Wershaw, R. L.; Reddy, M.M.

1995-01-01

An investigation of the strong-acid characteristics (pKa 3.0 or less) of fulvic acid from the Suwannee River, Georgia, was conducted. Quantitative determinations were made for amino acid and sulfur-containing acid structures, oxalate half-ester structures, malonic acid structures, keto acid structures, and aromatic carboxyl-group structures. These determinations were made by using a variety of spectrometric (13C-nuclear magnetic resonance, infrared, and ultraviolet spectrometry) and titrimetric characterizations on fulvic acid or fulvic acid samples that were chemically derivatized to indicate certain functional groups. Only keto acid and aromatic carboxyl-group structures contributed significantly to the strong-acid characteristics of the fulvic acid; these structures accounted for 43% of the strong-acid acidity. The remaining 57% of the strong acids are aliphatic carboxyl groups in unusual and/or complex configurations for which limited model compound data are available.

Vibrational Excitations and Low Energy Electronic Structure of Epoxide-decorated Graphene.

PubMed

Mattson, E C; Johns, J E; Pande, K; Bosch, R A; Cui, S; Gajdardziska-Josifovska, M; Weinert, M; Chen, J H; Hersam, M C; Hirschmugl, C J

2014-01-02

We report infrared studies of adsorbed atomic oxygen (epoxide functional groups) on graphene. Two different systems are used as a platform to explore these interactions, namely, epitaxial graphene/SiC(0001) functionalized with atomic oxygen (graphene epoxide, GE) and chemically reduced graphene oxide (RGO). In the case of the model GE system, IR reflectivity measurements show that epoxide groups distort the graphene π bands around the K-point, imparting a finite effective mass and contributing to a band gap. In the case of RGO, epoxide groups are found to be present following the reduction treatment by a combination of polarized IR reflectance and transmittance measurements. Similar to the GE system, a band gap in the RGO sample is observed as well.

Vibrational Excitations and Low Energy Electronic Structure of Epoxide-decorated Graphene

PubMed Central

Mattson, E.C.; Johns, J.E.; Pande, K.; Bosch, R.A.; Cui, S.; Gajdardziska-Josifovska, M.; Weinert, M.; Chen, J.H.; Hersam, M.C.; Hirschmugl, C.J.

2014-01-01

We report infrared studies of adsorbed atomic oxygen (epoxide functional groups) on graphene. Two different systems are used as a platform to explore these interactions, namely, epitaxial graphene/SiC(0001) functionalized with atomic oxygen (graphene epoxide, GE) and chemically reduced graphene oxide (RGO). In the case of the model GE system, IR reflectivity measurements show that epoxide groups distort the graphene π bands around the K-point, imparting a finite effective mass and contributing to a band gap. In the case of RGO, epoxide groups are found to be present following the reduction treatment by a combination of polarized IR reflectance and transmittance measurements. Similar to the GE system, a band gap in the RGO sample is observed as well. PMID:24563725

Cooperative Learning Groups and the Evolution of Human Adaptability : (Another Reason) Why Hermits Are Rare in Tonga and Elsewhere.

PubMed

Bell, Adrian Viliami; Hernandez, Daniel

2017-03-01

Understanding the prevalence of adaptive culture in part requires understanding the dynamics of learning. Here we explore the adaptive value of social learning in groups and how formal social groups function as effective mediums of information exchange. We discuss the education literature on Cooperative Learning Groups (CLGs), which outlines the potential of group learning for enhancing learning outcomes. Four qualities appear essential for CLGs to enhance learning: (1) extended conversations, (2) regular interactions, (3) gathering of experts, and (4) incentives for sharing knowledge. We analyze these four qualities within the context of a small-scale agricultural society using data we collected in 2010 and 2012. Through an analysis of surveys, interviews, and observations in the Tongan islands, we describe the role CLGs likely plays in facilitating individuals' learning of adaptive information. Our analysis of group affiliation, membership, and topics of conversation suggest that the first three CLG qualities reflect conditions for adaptive learning in groups. We utilize ethnographic anecdotes to suggest the fourth quality is also conducive to adaptive group learning. Using an evolutionary model, we further explore the scope for CLGs outside the Tongan socioecological context. Model analysis shows that environmental volatility and migration rates among human groups mediate the scope for CLGs. We call for wider attention to how group structure facilitates learning in informal settings, which may be key to assessing the contribution of groups to the evolution of complex, adaptive culture.

Non-additivity of functional group contributions in protein-ligand binding: a comprehensive study by crystallography and isothermal titration calorimetry.

PubMed

Baum, Bernhard; Muley, Laveena; Smolinski, Michael; Heine, Andreas; Hangauer, David; Klebe, Gerhard

2010-04-09

Additivity of functional group contributions to protein-ligand binding is a very popular concept in medicinal chemistry as the basis of rational design and optimized lead structures. Most of the currently applied scoring functions for docking build on such additivity models. Even though the limitation of this concept is well known, case studies examining in detail why additivity fails at the molecular level are still very scarce. The present study shows, by use of crystal structure analysis and isothermal titration calorimetry for a congeneric series of thrombin inhibitors, that extensive cooperative effects between hydrophobic contacts and hydrogen bond formation are intimately coupled via dynamic properties of the formed complexes. The formation of optimal lipophilic contacts with the surface of the thrombin S3 pocket and the full desolvation of this pocket can conflict with the formation of an optimal hydrogen bond between ligand and protein. The mutual contributions of the competing interactions depend on the size of the ligand hydrophobic substituent and influence the residual mobility of ligand portions at the binding site. Analysis of the individual crystal structures and factorizing the free energy into enthalpy and entropy demonstrates that binding affinity of the ligands results from a mixture of enthalpic contributions from hydrogen bonding and hydrophobic contacts, and entropic considerations involving an increasing loss of residual mobility of the bound ligands. This complex picture of mutually competing and partially compensating enthalpic and entropic effects determines the non-additivity of free energy contributions to ligand binding at the molecular level. (c) 2010 Elsevier Ltd. All rights reserved.

Contributions of dysglycemia, obesity and insulin resistance to impaired endothelium-dependent vasodilation in humans

PubMed Central

Han, KA; Patel, Y; Lteif, AA; Chisholm, R; Mather, KJ

2011-01-01

Background Individual effects of hyperglycemia and obesity to impair vascular health are recognized. However, the relative contributions of dysglycemia versus other obesity-related traits to vascular dysfunction have not been systematically evaluated. Methods We undertook a cross-sectional evaluation of factors contributing to vascular function in 271 consecutive subjects, categorized as non-obese normal glucose tolerant (n=115), non-obese dysglycemic (n=32), obese normal glucose tolerant (n=57), obese dysglycemic (n=38), or type 2 diabetic (n=29). Vascular function was measured invasively as leg blood flow responses to methacholine chloride, an endothelium-dependent vasodilator. Categorical and continuous analyses were used to assess the contributions of hyperglycemia to vascular dysfunction. Results Even among normoglycemic subjects, obese subjects had impaired vascular function compared to non-obese subjects (p=0.004). Vascular function was also impaired in non-obese dysglycemic subjects (p=0.04 versus non-obese normoglycemic subjects), to a level comparable to normoglycemic obese subjects. Within obese subject groups, gradations of dysglycemia including the presence of diabetes were not associated with further worsening of these vascular responses beyond the effect of obesity alone (p=NS comparing all obese groups, p<0.001 versus lean normoglycemic subjects). In univariate and multivariable modeling analyses we found that effects of glycemia were less powerful than effects of insulin resistance and obesity on vascular dysfunction. Conclusions Dysglycemia contributes to impaired vascular function in non-obese subjects, but obesity and insulin resistance are more important determinants of vascular function in obese and diabetic subjects. PMID:21309061

Innovation Related to the Tenure, Succession Pattern and Reference Group Orientation of the Principal. Final Report.

ERIC Educational Resources Information Center

Reynolds, James A.; Reynolds, Larry J.

The purposes of this study were to develop a conceptual rationale that might serve as the basis for a model of the change process and to test hypotheses derived from the rationale. It was believed that this approach would make a contribution to a growing body of research which views the school in the broader context of organizational theory. The…

Pre-school children with and without developmental delay: behaviour problems and parenting stress over time.

PubMed

Baker, B L; McIntyre, L L; Blacher, J; Crnic, K; Edelbrock, C; Low, C

2003-01-01

Children with intellectual disability are at heightened risk for behaviour problems and diagnosed mental disorder. The present authors studied the early manifestation and continuity of problem behaviours in 205 pre-school children with and without developmental delays. Behaviour problems were quite stable over the year from age 36-48 months. Children with developmental delays were rated higher on behaviour problems than their non-delayed peers, and were three times as likely to score in the clinical range. Mothers and fathers showed high agreement in their rating of child problems, especially in the delayed group. Parenting stress was also higher in the delayed group, but was related to the extent of behaviour problems rather than to the child's developmental delay. Over time, a transactional model fit the relationship between parenting stress and behaviour problems: high parenting stress contributed to a worsening in child behaviour problems over time, and high child behaviour problems contributed to a worsening in parenting stress. Findings for mothers and fathers were quite similar.

Group B Streptococcal Serine-Rich Repeat Proteins Promote Interaction With Fibrinogen and Vaginal Colonization

PubMed Central

Wang, Nai-Yu; Patras, Kathryn A.; Seo, Ho Seong; Cavaco, Courtney K.; Rösler, Berenice; Neely, Melody N.; Sullam, Paul M.; Doran, Kelly S.

2014-01-01

Group B streptococcus (GBS) can cause severe disease in susceptible hosts, including newborns, pregnant women, and the elderly. GBS serine-rich repeat (Srr) surface glycoproteins are important adhesins/invasins in multiple host tissues, including the vagina. However, exact molecular mechanisms contributing to their importance in colonization are unknown. We have recently determined that Srr proteins contain a fibrinogen-binding region (BR) and hypothesize that Srr-mediated fibrinogen binding may contribute to GBS cervicovaginal colonization. In this study, we observed that fibrinogen enhanced wild-type GBS attachment to cervical and vaginal epithelium, and that this was dependent on Srr1. Moreover, purified Srr1-BR peptide bound directly to host cells, and peptide administration in vivo reduced GBS recovery from the vaginal tract. Furthermore, a GBS mutant strain lacking only the Srr1 “latching” domain exhibited decreased adherence in vitro and decreased persistence in a mouse model of GBS vaginal colonization, suggesting the importance of Srr–fibrinogen interactions in the female reproductive tract. PMID:24620021

Age-Related Changes in Visual Temporal Order Judgment Performance: Relation to Sensory and Cognitive Capacities

PubMed Central

Busey, Thomas; Craig, James; Clark, Chris; Humes, Larry

2010-01-01

Five measures of temporal order judgments were obtained from 261 participants, including 146 elder, 44 middle aged, and 71 young participants. Strong age group differences were observed in all five measures, although the group differences were reduced when letter discriminability was matched for all participants. Significant relations were found between these measures of temporal processing and several cognitive and sensory assays, and structural equation modeling revealed the degree to which temporal order processing can be viewed as a latent factor that depends in part on contributions from sensory and cognitive capacities. The best-fitting model involved two different latent factors representing temporal order processing at same and different locations, and the sensory and cognitive factors were more successful predicting performance in the different location factor than the same-location factor. Processing speed, even measured using high-contrast symbols on a paper-and-pencil test, was a surprisingly strong predictor of variability in both latent factors. However, low-level sensory measures also made significant contributions to the latent factors. The results demonstrate the degree to which temporal order processing relates to other perceptual and cognitive capacities, and address the question of whether age-related declines in these capacities share a common cause. PMID:20580644

Age-related changes in visual temporal order judgment performance: Relation to sensory and cognitive capacities.

PubMed

Busey, Thomas; Craig, James; Clark, Chris; Humes, Larry

2010-08-06

Five measures of temporal order judgments were obtained from 261 participants, including 146 elder, 44 middle aged, and 71 young participants. Strong age group differences were observed in all five measures, although the group differences were reduced when letter discriminability was matched for all participants. Significant relations were found between these measures of temporal processing and several cognitive and sensory assays, and structural equation modeling revealed the degree to which temporal order processing can be viewed as a latent factor that depends in part on contributions from sensory and cognitive capacities. The best-fitting model involved two different latent factors representing temporal order processing at same and different locations, and the sensory and cognitive factors were more successful predicting performance in the different location factor than the same-location factor. Processing speed, even measured using high-contrast symbols on a paper-and-pencil test, was a surprisingly strong predictor of variability in both latent factors. However, low-level sensory measures also made significant contributions to the latent factors. The results demonstrate the degree to which temporal order processing relates to other perceptual and cognitive capacities, and address the question of whether age-related declines in these capacities share a common cause. Copyright 2010 Elsevier Ltd. All rights reserved.

Waves, modes and properties with a major impact on dynamic pantograph-catenary interaction

NASA Astrophysics Data System (ADS)

Vo Van, Olivier; Massat, Jean-Pierre; Balmes, Etienne

2017-08-01

Understanding the dynamic behavior of the pantograph-catenary system is crucial for design improvement, but many factors influence the contact force, which is the main design objective. To give a proper understanding of dynamic characteristics, the paper uses a combination of mass drop tests on a catenary, analytic models and parametric finite element model simulations allowing a fine analysis of the influence of train speed. The first contributor to contact force variations is the geometry of the catenary under gravity loading. This parameter is however shown to be insufficient to explain higher frequency effects. The second contributor is the propagation of waves in the contact and messenger wires. The influence of wave dispersion is first demonstrated, which emphasizes the importance of considering the bending stiffness. Wave compensation by droppers and reflections at the mast are then shown to be important. Characteristic times associated with wave group velocities are finally used to explain the series of harmonic contributions visible in spectra in the catenary and pantograph frames. Finally, modes are shown to play a role particularly when their frequencies coincide with other contributions. The notion of mode groups, associated wave velocities and relevant design variables are discussed. Several observations pave the way for future work on catenary design.

Cognitive decision modelling of emotion-based learning impairment in schizophrenia: the role of awareness.

PubMed

Cella, Matteo; Dymond, Simon; Cooper, Andrew; Turnbull, Oliver H

2012-03-30

Individuals with schizophrenia often lack insight or awareness. Resulting impairment has been observed in various cognitive domains and, recently, linked to problems in emotion-based learning. The Iowa Gambling Task (IGT) has been used to assess emotion-based decision-making in patients with schizophrenia, but results have been inconclusive. The current study further investigates emotion-based decision-making in schizophrenia by elucidating the unique contribution of awareness. Twenty-five patients with schizophrenia and 24 healthy controls were assessed with a modified version of the IGT recording awareness at regular intervals. Symptom assessment, medication and medical history were recorded for the clinical group. Patients with schizophrenia underperformed on the IGT compared to controls. Subjective awareness levels were significantly lower in the schizophrenia group and were associated with hallucination severity. Cognitive decision modelling further indicated that patients with schizophrenia had impaired attention to losses, compared to controls. This parameter was positively correlated with awareness. We also found that positive symptoms altered awareness levels and suggest that this disruption may contribute to sub-optimal decision-making. Overall, a lack of awareness may be an important aspect in understanding impaired social cognitive functioning and emotion-based learning observed in schizophrenia. Copyright © 2011 Elsevier Ltd. All rights reserved.

Visual-spatial abilities relate to mathematics achievement in children with heavy prenatal alcohol exposure

PubMed Central

Crocker, N.; Riley, E.P.; Mattson, S.N.

2014-01-01

Objective The current study examined the relationship between mathematics and attention, working memory, and visual memory in children with heavy prenatal alcohol exposure and controls. Method Fifty-six children (29 AE, 27 CON) were administered measures of global mathematics achievement (WRAT-3 Arithmetic & WISC-III Written Arithmetic), attention, (WISC-III Digit Span forward and Spatial Span forward), working memory (WISC-III Digit Span backward and Spatial Span backward), and visual memory (CANTAB Spatial Recognition Memory and Pattern Recognition Memory). The contribution of cognitive domains to mathematics achievement was analyzed using linear regression techniques. Attention, working memory and visual memory data were entered together on step 1 followed by group on step 2, and the interaction terms on step 3. Results Model 1 accounted for a significant amount of variance in both mathematics achievement measures, however, model fit improved with the addition of group on step 2. Significant predictors of mathematics achievement were Spatial Span forward and backward and Spatial Recognition Memory. Conclusions These findings suggest that deficits in spatial processing may be related to math impairments seen in FASD. In addition, prenatal alcohol exposure was associated with deficits in mathematics achievement, above and beyond the contribution of general cognitive abilities. PMID:25000323

Visual-spatial abilities relate to mathematics achievement in children with heavy prenatal alcohol exposure.

PubMed

Crocker, Nicole; Riley, Edward P; Mattson, Sarah N

2015-01-01

The current study examined the relationship between mathematics and attention, working memory, and visual memory in children with heavy prenatal alcohol exposure and controls. Subjects were 56 children (29 AE, 27 CON) who were administered measures of global mathematics achievement (WRAT-3 Arithmetic & WISC-III Written Arithmetic), attention, (WISC-III Digit Span forward and Spatial Span forward), working memory (WISC-III Digit Span backward and Spatial Span backward), and visual memory (CANTAB Spatial Recognition Memory and Pattern Recognition Memory). The contribution of cognitive domains to mathematics achievement was analyzed using linear regression techniques. Attention, working memory, and visual memory data were entered together on Step 1 followed by group on Step 2, and the interaction terms on Step 3. Model 1 accounted for a significant amount of variance in both mathematics achievement measures; however, model fit improved with the addition of group on Step 2. Significant predictors of mathematics achievement were Spatial Span forward and backward and Spatial Recognition Memory. These findings suggest that deficits in spatial processing may be related to math impairments seen in FASD. In addition, prenatal alcohol exposure was associated with deficits in mathematics achievement, above and beyond the contribution of general cognitive abilities. PsycINFO Database Record (c) 2015 APA, all rights reserved.

A clinical investigation of motivation to change standards and cognitions about failure in perfectionism.

PubMed

Egan, Sarah J; Piek, Jan P; Dyck, Murray J; Rees, Clare S; Hagger, Martin S

2013-10-01

Clinical perfectionism is a transdiagnostic process that has been found to maintain eating disorders, anxiety disorders and depression. Cognitive behavioural models explaining the maintenance of clinical perfectionism emphasize the contribution of dichotomous thinking and resetting standards higher following both success and failure in meeting their goals. There has been a paucity of research examining the predictions of the models and motivation to change perfectionism. Motivation to change is important as individuals with clinical perfectionism often report many perceived benefits of their perfectionism; they are, therefore, likely to be ambivalent regarding changing perfectionism. The aim was to compare qualitative responses regarding questions about motivation to change standards and cognitions regarding failure to meet a personal standard in two contrasting groups with high and low negative perfectionism. Negative perfectionism refers to concern over not meeting personal standards. A clinical group with a range of axis 1 diagnoses who were elevated on negative perfectionism were compared to a group of athletes who were low on negative perfectionism. Results indicated that the clinical group perceived many negative consequences of their perfectionism. They also, however, reported numerous benefits and the majority stated that they would prefer not to change their perfectionism. The clinical group also reported dichotomous thinking and preferring to either keep standards the same or reset standards higher following failure, whilst the athlete group reported they would keep standards the same or set them lower. The findings support predictions of the cognitive behavioural model of clinical perfectionism.

The effects of ventilation with high density oxygen on the strength of gastrointestinal anastomosis

PubMed Central

Eker, Tevfik; Sevim, Yusuf; Cumaogullari, Ozge; Ozcelik, Menekse; Kocaay, Akin Firat; Ensari, Cemal Özben; Pasaoglu, Ozge Tugce

2015-01-01

Purpose The aim of our study is to evaluate the effects of administration of perioperative supplemental oxygen on anastomoses. Methods Forty male Wistar albino rats were used in the study and randomized into 4 groups. Ischemia-reperfusion models were built in groups 3 and 4. Jejunojejunostomy was performed in all rats and assigned to an oxygen/nitrous oxide mixture with a fraction of inspired oxygen of 30% in groups 1 and 3 and 80% in groups 2 and 4. The measurements of perianastomotic tissue oxygen pressure, bursting pressure, level of hydroxyproline were evaluated and compared in all groups. Results The perianastomotic tissue oxygen pressures, bursting pressures and levels of hydroxyproline were identified as significantly high in groups 2 and 4, administered a fraction of inspired oxygen of 80%, compared to groups 1 and 3, administered a fraction of inspired oxygen of 30%. Conclusion Perioperative supplemental oxygen contributes positively to the anastomotic healing. PMID:26131440

Relationships Between the External and Internal Training Load in Professional Soccer: What Can We Learn From Machine Learning?

PubMed

Jaspers, Arne; De Beéck, Tim Op; Brink, Michel S; Frencken, Wouter G P; Staes, Filip; Davis, Jesse J; Helsen, Werner F

2018-05-01

Machine learning may contribute to understanding the relationship between the external load and internal load in professional soccer. Therefore, the relationship between external load indicators (ELIs) and the rating of perceived exertion (RPE) was examined using machine learning techniques on a group and individual level. Training data were collected from 38 professional soccer players over 2 seasons. The external load was measured using global positioning system technology and accelerometry. The internal load was obtained using the RPE. Predictive models were constructed using 2 machine learning techniques, artificial neural networks and least absolute shrinkage and selection operator (LASSO) models, and 1 naive baseline method. The predictions were based on a large set of ELIs. Using each technique, 1 group model involving all players and 1 individual model for each player were constructed. These models' performance on predicting the reported RPE values for future training sessions was compared with the naive baseline's performance. Both the artificial neural network and LASSO models outperformed the baseline. In addition, the LASSO model made more accurate predictions for the RPE than did the artificial neural network model. Furthermore, decelerations were identified as important ELIs. Regardless of the applied machine learning technique, the group models resulted in equivalent or better predictions for the reported RPE values than the individual models. Machine learning techniques may have added value in predicting RPE for future sessions to optimize training design and evaluation. These techniques may also be used in conjunction with expert knowledge to select key ELIs for load monitoring.

First-trimester prediction of birth weight.

PubMed

Boucoiran, Isabelle; Djemli, Anissa; Taillefer, Catherine; Rypens, Françoise; Delvin, Edgard; Audibert, François

2013-09-01

To determine whether the parameters used in first-trimester screening for aneuploidies contribute significantly to the prediction of birth weight. In this retrospective cohort study (n = 4110), nuchal translucency (NT), free β-chorionic gonadotropin (fβ-hCG), and pregnancy-associated plasma protein-A (PAPP-A) blood concentrations were measured between 11 + 0 and 13 + 6 weeks. Multiple pregnancies, chromosomal anomalies, major fetal defects, and deliveries before 24 weeks were excluded. NT (0.95 versus 0.98 multiples of the expected median [MoM], p < 0.001) and PAPP-A (0.93 versus 1.06 MoM, p = 0.005) were significantly lower in small-for-gestational-age (SGA) newborns (<10th percentile) than the unaffected group, but not fβ-hCG (0.89 versus 0.93 MoM, p = 0.113). NT was significantly higher (1.03 versus 0.98 MoM, p < 0.001) in the large-for-gestational-age (LGA) group (>90th percentile) compared with the unaffected group, and biomarkers did not differ. After controlling for gestational age, maternal weight, smoking status, ethnicity, and fetal sex, first-trimester markers contributed to the prediction of birth weight in a multiple linear model but did not significantly improved the prediction of SGA and LGA compared with maternal characteristics alone. Parameters used in first-trimester screening for aneuploidies contribute to the prediction of birth weight but their clinical utility to detect women at risk of SGA or LGA baby is limited. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

The Propulsion Model of Creative Contributions Applied to the Arts and Letters.

ERIC Educational Resources Information Center

Sternberg, Robert J.; Kaufman, James C.; Pretz, Jean E.

2001-01-01

This article applies a propulsion model of creative contributions to the arts and letters. It opens with a general discussion of creative contributions and reviews existing models before describing the propulsion model and suggesting eight types of contributions that follow from this model. Examples illustrate use of the model in understanding…

Effect of Chronic Restraint Stress on HPA Axis Activity and Expression of BDNF and Trkb in the Hippocampus of Pregnant Rats: Possible Contribution in Depression during Pregnancy and Postpartum Period.

PubMed

Maghsoudi, Nader; Ghasemi, Rasoul; Ghaempanah, Zahra; Ardekani, Ali M; Nooshinfar, Elahe; Tahzibi, Abbas

2014-01-01

Brain-Derived Neurotrophic Factor (BDNF) and its receptor, TrkB, in the hippocampus are targets for adverse effects of stress paradigms; in addition, BDNF and its receptor play key role in the pathology of brain diseases like depression. In the present study, we evaluated the possible role of hippocampal BDNF in depression during pregnancy. To achieve the purpose, repeated restrain stress (1 or 3 hours daily for 7 days) during the last week of pregnancy was used and alteration in the gene expression of hippocampal BDNF and TrkB evaluated by semi-quantitative PCR. The results showed that in stress group the level of ACTH and Corticosterone is increased showing that our model was efficient in inducing psychological stress; we also found that BDNF and TrkB expression are decreased in 3 hours stress group but not in 1 hour stress compared to control group. Our results imply that decrease in BDNF and its receptor could contribute in some adverse effects of stress during pregnancy such as elevation of depressive like behavior.

Computational identification of structural factors affecting the mutagenic potential of aromatic amines: study design and experimental validation.

PubMed

Slavov, Svetoslav H; Stoyanova-Slavova, Iva; Mattes, William; Beger, Richard D; Brüschweiler, Beat J

2018-07-01

A grid-based, alignment-independent 3D-SDAR (three-dimensional spectral data-activity relationship) approach based on simulated 13 C and 15 N NMR chemical shifts augmented with through-space interatomic distances was used to model the mutagenicity of 554 primary and 419 secondary aromatic amines. A robust modeling strategy supported by extensive validation including randomized training/hold-out test set pairs, validation sets, "blind" external test sets as well as experimental validation was applied to avoid over-parameterization and build Organization for Economic Cooperation and Development (OECD 2004) compliant models. Based on an experimental validation set of 23 chemicals tested in a two-strain Salmonella typhimurium Ames assay, 3D-SDAR was able to achieve performance comparable to 5-strain (Ames) predictions by Lhasa Limited's Derek and Sarah Nexus for the same set. Furthermore, mapping of the most frequently occurring bins on the primary and secondary aromatic amine structures allowed the identification of molecular features that were associated either positively or negatively with mutagenicity. Prominent structural features found to enhance the mutagenic potential included: nitrobenzene moieties, conjugated π-systems, nitrothiophene groups, and aromatic hydroxylamine moieties. 3D-SDAR was also able to capture "true" negative contributions that are particularly difficult to detect through alternative methods. These include sulphonamide, acetamide, and other functional groups, which not only lack contributions to the overall mutagenic potential, but are known to actively lower it, if present in the chemical structures of what otherwise would be potential mutagens.

Challenges in volunteering from cancer care volunteers perspectives.

PubMed

Kamaludin, Kauthar Mohamad; Muhammad, Mazanah; Wahat, Nor Wahiza Abdul; Ibrahim, Rahimah

2013-01-01

The involvement of non-government organizations (NGOs) and support groups has helped strengthen public health services in addressing cancer care burden. Owing to the contribution of volunteers in cancer care, this article documents a qualitative study that examined challenges in attracting and retaining cancer care volunteers as part of the effort to develop a volunteer recruitment model. Data were collected through three focus group discussions involving 19 cancer support group members in Malaysia. Findings of the study revealed that mobility and locality appeared to be significant in Malaysian context, while the need for financial support and time flexibility are challenges faced by cancer support groups to attract and retain volunteers. The findings imply that cancer care initiatives can benefit from more local volunteers but at the same time these volunteers require flexibility and financial support to sustain their engagement.

Disruption of visual circuit formation and refinement in a mouse model of autism

PubMed Central

Khanbabaei, Maryam; Murari, Kartikeya; Rho, Jong M.

2016-01-01

Aberrant connectivity is believed to contribute to the pathophysiology of autism spectrum disorder (ASD). Recent neuroimaging studies have increasingly identified such impairments in patients with ASD, including alterations in sensory systems. However, the cellular substrates and molecular underpinnings of disrupted connectivity remain poorly understood. Utilizing eye‐specific segregation in the dorsal lateral geniculate nucleus (dLGN) as a model system, we investigated the formation and refinement of precise patterning of synaptic connections in the BTBR T + tf/J (BTBR) mouse model of ASD. We found that at the neonatal stage, the shape of the dLGN occupied by retinal afferents was altered in the BTBR group compared to C57BL/6J (B6) animals. Notably, the degree of overlap between the ipsi‐ and contralateral afferents was significantly greater in the BTBR mice. Moreover, these abnormalities continued into mature stage in the BTBR animals, suggesting persistent deficits rather than delayed maturation of axonal refinement. Together, these results indicate disrupted connectivity at the synaptic patterning level in the BTBR mice, suggesting that in general, altered neural circuitry may contribute to autistic behaviours seen in this animal model. In addition, these data are consistent with the notion that lower‐level, primary processing mechanisms contribute to altered visual perception in ASD. Autism Res 2017, 10: 212–223. © 2016 The Authors Autism Research published by Wiley Periodicals, Inc. on behalf of International Society for Autism Research. PMID:27529416

A Sensitivity Analysis of an Inverted Pendulum Balance Control Model.

PubMed

Pasma, Jantsje H; Boonstra, Tjitske A; van Kordelaar, Joost; Spyropoulou, Vasiliki V; Schouten, Alfred C

2017-01-01

Balance control models are used to describe balance behavior in health and disease. We identified the unique contribution and relative importance of each parameter of a commonly used balance control model, the Independent Channel (IC) model, to identify which parameters are crucial to describe balance behavior. The balance behavior was expressed by transfer functions (TFs), representing the relationship between sensory perturbations and body sway as a function of frequency, in terms of amplitude (i.e., magnitude) and timing (i.e., phase). The model included an inverted pendulum controlled by a neuromuscular system, described by several parameters. Local sensitivity of each parameter was determined for both the magnitude and phase using partial derivatives. Both the intrinsic stiffness and proportional gain shape the magnitude at low frequencies (0.1-1 Hz). The derivative gain shapes the peak and slope of the magnitude between 0.5 and 0.9 Hz. The sensory weight influences the overall magnitude, and does not have any effect on the phase. The effect of the time delay becomes apparent in the phase above 0.6 Hz. The force feedback parameters and intrinsic stiffness have a small effect compared with the other parameters. All parameters shape the TF magnitude and phase and therefore play a role in the balance behavior. The sensory weight, time delay, derivative gain, and the proportional gain have a unique effect on the TFs, while the force feedback parameters and intrinsic stiffness contribute less. More insight in the unique contribution and relative importance of all parameters shows which parameters are crucial and critical to identify underlying differences in balance behavior between different patient groups.

Aluminum Exposure from Parenteral Nutrition: Early Bile Canaliculus Changes of the Hepatocyte.

PubMed

Hall, Amanda R; Le, Ha; Arnold, Chris; Brunton, Janet; Bertolo, Robert; Miller, Grant G; Zello, Gordon A; Sergi, Consolato

2018-06-04

Background: Neonates on long-term parenteral nutrition (PN) may develop parenteral nutrition-associated liver disease (PNALD). Aluminum (Al) is a known contaminant of infant PN, and we hypothesize that it substantially contributes to PNALD. In this study, we aim to assess the impact of Al on hepatocytes in a piglet model. Methods: We conducted a randomized control trial using a Yucatan piglet PN model. Piglets, aged 3⁻6 days, were placed into two groups. The high Al group ( n = 8) received PN with 63 µg/kg/day of Al, while the low Al group ( n = 7) received PN with 24 µg/kg/day of Al. Serum samples for total bile acids (TBA) were collected over two weeks, and liver tissue was obtained at the end of the experiment. Bile canaliculus morphometry were studied by transmission electron microscopy (TEM) and ImageJ software analysis. Results: The canalicular space was smaller and the microvilli were shorter in the high Al group than in the low Al group. There was no difference in the TBA between the groups. Conclusions: Al causes structural changes in the hepatocytes despite unaltered serum bile acids. High Al in PN is associated with short microvilli, which could decrease the functional excretion area of the hepatocytes and impair bile flow.

Didactical suggestion for a Dynamic Hybrid Intelligent e-Learning Environment (DHILE) applying the PENTHA ID Model

NASA Astrophysics Data System (ADS)

dall'Acqua, Luisa

2011-08-01

The teleology of our research is to propose a solution to the request of "innovative, creative teaching", proposing a methodology to educate creative Students in a society characterized by multiple reference points and hyper dynamic knowledge, continuously subject to reviews and discussions. We apply a multi-prospective Instructional Design Model (PENTHA ID Model), defined and developed by our research group, which adopts a hybrid pedagogical approach, consisting of elements of didactical connectivism intertwined with aspects of social constructivism and enactivism. The contribution proposes an e-course structure and approach, applying the theoretical design principles of the above mentioned ID Model, describing methods, techniques, technologies and assessment criteria for the definition of lesson modes in an e-course.

It's fun to transcribe with Fun30: A model for nucleosome dynamics during RNA polymerase II-mediated elongation.

PubMed

Lee, Junwoo; Choi, Eun Shik; Lee, Daeyoup

2018-01-01

The ability of elongating RNA polymerase II (RNAPII) to regulate the nucleosome barrier is poorly understood because we do not know enough about the involved factors and we lack a conceptual framework to model this process. Our group recently identified the conserved Fun30/SMARCAD1 family chromatin-remodeling factor, Fun30 Fft3 , as being critical for relieving the nucleosome barrier during RNAPII-mediated elongation, and proposed a model illustrating how Fun30 Fft3 may contribute to nucleosome disassembly during RNAPII-mediated elongation. Here, we present a model that describes nucleosome dynamics during RNAPII-mediated elongation in mathematical terms and addresses the involvement of Fun30 Fft3 in this process.

The Role of Peer Group Aggression in Predicting Adolescent Dating Violence and Relationship Quality

ERIC Educational Resources Information Center

Ellis, Wendy E.; Chung-Hall, Janet; Dumas, Tara M.

2013-01-01

Past research has shown that adolescent peer groups make a significant contribution to shaping behavior but less is known about the role of peer groups in adolescent dating relationships. This longitudinal study examined the contribution of aggressive peer group norms on relationship quality and dating violence among dating adolescents. At the…

Lorazepam reinstates punishment-suppressed remifentanil self-administration in rats.

PubMed

Panlilio, Leigh V; Thorndike, Eric B; Schindler, Charles W

2005-05-01

We recently described a reinstatement procedure that models relapse to drug abuse in cases where abstinence results from aversive consequences of drug use. The potential value of this punishment-based model of relapse depends on its sensitivity to relapse-inducing events that are ineffective in the widely used extinction-based model. It is known that certain drugs can have anti-punishment effects, but these drugs have not been tested in the punishment-based reinstatement procedure. Therefore, the effects of the benzodiazepine, lorazepam, were examined using punishment-based and extinction-based reinstatement procedures. Rats self-administered the opioid, remifentanil (4 microg/kg per infusion). Two punishment groups were trained with response-contingent footshock that suppressed baseline rates of responding to zero. In an extinction group, remifentanil delivery was discontinued, and baseline responding stabilized at a low rate (mean=0.06 responses/min). Lorazepam (0.08-10 mg/kg, IP) was given during test sessions with the shock contingency discontinued for both punishment groups. Remifentanil delivery was maintained during testing in one punishment group but not the other. Lorazepam reinstated self-administration responding in both punishment groups but not in the extinction group. Priming injections of heroin reinstated responding in both the punishment and extinction groups, but combining heroin and lorazepam did not enhance reinstatement. This is the first demonstration that a trigger for relapse may have different effects depending on whether aversive conditioning contributed to the achievement of abstinence. It may be important to consider potential anti-punishment effects of both abused drugs and therapeutic agents in the treatment of individuals with a history of drug abuse.

Physical-Socio-Economic Modeling of Climate Change

NASA Astrophysics Data System (ADS)

Chamberlain, R. G.; Vatan, F.

2008-12-01

Because of the global nature of climate change, any assessment of the effects of plans, policies, and response to climate change demands a model that encompasses the entire Earth System, including socio- economic factors. Physics-based climate models of the factors that drive global temperatures, rainfall patterns, and sea level are necessary but not sufficient to guide decision making. Actions taken by farmers, industrialists, environmentalists, politicians, and other policy makers may result in large changes to economic factors, international relations, food production, disease vectors, and beyond. These consequences will not be felt uniformly around the globe or even across a given region. Policy models must comprehend all of these considerations. Combining physics-based models of the Earth's climate and biosphere with societal models of population dynamics, economics, and politics is a grand challenge with high stakes. We propose to leverage our recent advances in modeling and simulation of military stability and reconstruction operations to models that address all these areas of concern. Following over twenty years' experience of successful combat simulation, JPL has started developing Minerva, which will add demographic, economic, political, and media/information models to capabilities that already exist. With these new models, for which we have design concepts, it will be possible to address a very wide range of potential national and international problems that were previously inaccessible. Our climate change model builds on Minerva and expands the geographical horizon from playboxes containing regions and neighborhoods to the entire globe. This system consists of a collection of interacting simulation models that specialize in different aspects of the global situation. They will each contribute to and draw from a pool of shared data. The basic models are: the physical model; the demographic model; the political model; the economic model; and the media/information operations model. Each of these models focuses on part of the overall picture while; each contributes information about its area of expertise to a common pool and draws from that pool and the feedbacks from the other models as needed. Existing high-quality physical models are based on analysis of the dynamic interactions of atmospheric, land, and ocean processes. The demographic model tracks the civilian demographics needed by the other models. The populations of neighborhood group age-gender cohorts are affected by births, deaths, aging, and migration. This model provides labor supply and product demand curves to the economic model. The political model focuses on political actors and describes how they use their clout to seek their goals. Clout is derived from civilian support, the formal and informal alliances that actors make with each other, military strength, wealth, and control of information. It considers how they are constrained by their cultural heritage. It deals with shifting alliances. The economic model determines local and international prices and production quantities for a small number of products, including imports and exports and black markets; wages, jobs, and unemployment for a small number of labor categories; capital, growth, and inflation; resource usage and pollution. The media/information operations model addresses the effects of the control and content of inter- group and intra-group communications-and the side effects of these on other groups. This model will consist of rules (probably a large number of them) detailing the effects of media/information operations of various kinds on civilian parameters used in the other models, such as political goals, concern saliencies, and shapes of supply and demand curves.

Kinetic modeling of α-hydrogen abstractions from unsaturated and saturated oxygenate compounds by hydrogen atoms.

PubMed

Paraskevas, Paschalis D; Sabbe, Maarten K; Reyniers, Marie-Françoise; Papayannakos, Nikos G; Marin, Guy B

2014-10-09

Hydrogen-abstraction reactions play a significant role in thermal biomass conversion processes, as well as regular gasification, pyrolysis, or combustion. In this work, a group additivity model is constructed that allows prediction of reaction rates and Arrhenius parameters of hydrogen abstractions by hydrogen atoms from alcohols, ethers, esters, peroxides, ketones, aldehydes, acids, and diketones in a broad temperature range (300-2000 K). A training set of 60 reactions was developed with rate coefficients and Arrhenius parameters calculated by the CBS-QB3 method in the high-pressure limit with tunneling corrections using Eckart tunneling coefficients. From this set of reactions, 15 group additive values were derived for the forward and the reverse reaction, 4 referring to primary and 11 to secondary contributions. The accuracy of the model is validated upon an ab initio and an experimental validation set of 19 and 21 reaction rates, respectively, showing that reaction rates can be predicted with a mean factor of deviation of 2 for the ab initio and 3 for the experimental values. Hence, this work illustrates that the developed group additive model can be reliably applied for the accurate prediction of kinetics of α-hydrogen abstractions by hydrogen atoms from a broad range of oxygenates.

Intergovernmental Panel on Climate Change (IPCC)\\, Working Group 1, 1994: Modelling Results Relating Future Atmospheric CO2 Concentrations to Industrial Emissions (DB1009)

DOE Data Explorer

Enting, I. G.; Wigley, M. L.; Heimann, M.

1995-01-01

This database contains the results of various projections of the relation between future CO2 concentrations and future industrial emissions. These projections were contributed by groups from a number of countries as part of the scientific assessment for the report, "Radiative Forcing of Climate Change" (1994), issued by Working Group 1 of the Intergovernmental Panel on Climate Change. There were three types of calculations: (1) forward projections, calculating the atmospheric CO2 concentrations resulting from specified emissions scenarios; (2) inverse calculations, determining the emission rates that would be required to achieve stabilization of CO2 concentrations via specified pathways; (3) impulse response function calculations, required for determining Global Warming Potentials. The projections were extrapolations of global carbon cycle models from pre-industrial times (starting at 1765) to 2100 or 2200 A.D. There were two aspects to the exercise: (1) an assessment of the uncertainty due to uncertainties regarding the current carbon budget, and (2) an assessment of the uncertainties arising from differences between models. To separate these effects, a set of standard conditions was used to explore inter-model differences and then a series of sensitivity studies was used to explore the consequences of current uncertainties in the carbon cycle.

Safety climate and the theory of planned behavior: towards the prediction of unsafe behavior.

PubMed

Fogarty, Gerard J; Shaw, Andrew

2010-09-01

The present study is concerned with the human factors that contribute to violations in aviation maintenance. Much of our previous research in this area has been based on safety climate surveys and the analysis of relations among core dimensions of climate. In this study, we tap into mainstream psychological theory to help clarify the mechanisms underlying the links between climate and behavior. Specifically, we demonstrate the usefulness of Ajzen's (1991, 2001) Theory of Planned Behavior (TPB) to understanding violation behaviors in aircraft maintenance. A questionnaire was administered to 307 aircraft maintenance workers. Constructs measured by the survey included perceptions of management attitudes to safety, own attitudes to violations, intention to violate, group norms, workplace pressures, and violations. A model based on the TPB illustrated hypothetical connections among these variables. Path analyses using AMOS suggested some theoretically justifiable modifications to the model. Fit statistics of the revised model were excellent with intentions, group norms, and personal attitudes combining to explain 50% of the variance in self-reported violations. The model highlighted the importance of management attitudes and group norms as direct and indirect predictors of violation behavior. We conclude that the TPB is a useful tool for understanding the psychological background to the procedural violations so often associated with incidents and accidents. 2009 Elsevier Ltd. All rights reserved.

Vasotocinergic control of agonistic behavior told by Neotropical fishes.

PubMed

Silva, Ana C; Pandolfi, Matías

2018-04-24

The hypothalamic neuropeptides of the vasopressin-oxytocin family (and their homologs for non-mammalian species) are key modulators of the Social Brain Network, acting via specific receptors reported in all the nuclei of this network. Different conclusive examples have proven the context-dependency actions of hypothalamic nonapeptides on social behavior in several vertebrate taxa. Teleost fishes provide endless possibilities of experimental model systems to explore the underlying mechanisms of nonapeptide actions on social behavior given that they are the most diverse group of vertebrates. Although it has been difficult to identify commonalities of nonapeptide actions across species, indisputable evidence in many teleost species have demonstrated a clear role of vasotocin in the modulation of aggressive and sexual behaviors. Though Neotropical South American fish contribute an important percentage of teleost diversity, most native species remain unexplored as model systems for the study of the neuroendocrine bases of social behavior. In this review, we will revise recent data on the two model systems of Neotropical fish, South American cichlids and weakly electric fish that have contributed to this issue. Copyright © 2018 Elsevier Inc. All rights reserved.

The TENCompetence Infrastructure: A Learning Network Implementation

NASA Astrophysics Data System (ADS)

Vogten, Hubert; Martens, Harrie; Lemmers, Ruud

The TENCompetence project developed a first release of a Learning Network infrastructure to support individuals, groups and organisations in professional competence development. This infrastructure Learning Network infrastructure was released as open source to the community thereby allowing users and organisations to use and contribute to this development as they see fit. The infrastructure consists of client applications providing the user experience and server components that provide the services to these clients. These services implement the domain model (Koper 2006) by provisioning the entities of the domain model (see also Sect. 18.4) and henceforth will be referenced as domain entity services.

Emergence of social cooperation in threshold public goods games with collective risk

NASA Astrophysics Data System (ADS)

Wang, Jing; Fu, Feng; Wu, Te; Wang, Long

2009-07-01

In real situations, people are often faced with the option of voluntary contribution to achieve a collective goal, for example, building a dam or a fence, in order to avoid an unfavorable loss. Those who do not donate, however, can free ride on others’ sacrifices. As a result, cooperation is difficult to maintain, leading to an enduring collective-risk social dilemma. To address this issue, here we propose a simple yet effective theoretical model of threshold public goods game with collective risk and focus on the effect of risk on the emergence of social cooperation. To do this, we consider the population dynamics represented by replicator equation for two simplifying scenarios, respectively: one with fair sharers, who contribute the minimum average amount versus defectors and the other with altruists contributing more than average versus defectors. For both cases, we find that the dilemma is relieved in high-risk situations where cooperation is likely to persist and dominate defection in the population. Large initial endowment to individuals also encourages the risk-averse action, which means that, as compared to poor players (with small initial endowment), wealthy individuals (with large initial endowment) are more likely to cooperate in order to protect their private accounts. In addition, we show that small donation amount and small threshold (collective target) can encourage and sustain cooperation. Furthermore, for other parameters fixed, the impacts of group size act differently on the two scenarios because of distinct mechanisms: in the former case where the cost of cooperation depends on the group size, large size of group readily results in defection, while easily maintains cooperation in the latter case where the cost of cooperation is fixed irrespective of the group size. Our theoretical results of the replicator dynamics are in excellent agreement with the individual based simulation results.

Individual differences in forced-choice recognition memory: partitioning contributions of recollection and familiarity.

PubMed

Migo, Ellen M; Quamme, Joel R; Holmes, Selina; Bendell, Andrew; Norman, Kenneth A; Mayes, Andrew R; Montaldi, Daniela

2014-01-01

In forced-choice recognition memory, two different testing formats are possible under conditions of high target-foil similarity: Each target can be presented alongside foils similar to itself (forced-choice corresponding; FCC), or alongside foils similar to other targets (forced-choice noncorresponding; FCNC). Recent behavioural and neuropsychological studies suggest that FCC performance can be supported by familiarity whereas FCNC performance is supported primarily by recollection. In this paper, we corroborate this finding from an individual differences perspective. A group of older adults were given a test of FCC and FCNC recognition for object pictures, as well as standardized tests of recall, recognition, and IQ. Recall measures were found to predict FCNC, but not FCC performance, consistent with a critical role for recollection in FCNC only. After the common influence of recall was removed, standardized tests of recognition predicted FCC, but not FCNC performance. This is consistent with a contribution of only familiarity in FCC. Simulations show that a two-process model, where familiarity and recollection make separate contributions to recognition, is 10 times more likely to give these results than a single-process model. This evidence highlights the importance of recognition memory test design when examining the involvement of recollection and familiarity.

Estimating the contribution of genetic variants to difference in incidence of disease between population groups.

PubMed

Moonesinghe, Ramal; Ioannidis, John P A; Flanders, W Dana; Yang, Quanhe; Truman, Benedict I; Khoury, Muin J

2012-08-01

Genome-wide association studies have identified multiple genetic susceptibility variants to several complex human diseases. However, risk-genotype frequency at loci showing robust associations might differ substantially among different populations. In this paper, we present methods to assess the contribution of genetic variants to the difference in the incidence of disease between different population groups for different scenarios. We derive expressions for the contribution of a single genetic variant, multiple genetic variants, and the contribution of the joint effect of a genetic variant and an environmental factor to the difference in the incidence of disease. The contribution of genetic variants to the difference in incidence increases with increasing difference in risk-genotype frequency, but declines with increasing difference in incidence between the two populations. The contribution of genetic variants also increases with increasing relative risk and the contribution of joint effect of genetic and environmental factors increases with increasing relative risk of the gene-environmental interaction. The contribution of genetic variants to the difference in incidence between two populations can be expressed as a function of the population attributable risks of the genetic variants in the two populations. The contribution of a group of genetic variants to the disparity in incidence of disease could change considerably by adding one more genetic variant to the group. Any estimate of genetic contribution to the disparity in incidence of disease between two populations at this stage seems to be an elusive goal.

Estimating the contribution of genetic variants to difference in incidence of disease between population groups

PubMed Central

Moonesinghe, Ramal; Ioannidis, John PA; Flanders, W Dana; Yang, Quanhe; Truman, Benedict I; Khoury, Muin J

2012-01-01

Genome-wide association studies have identified multiple genetic susceptibility variants to several complex human diseases. However, risk-genotype frequency at loci showing robust associations might differ substantially among different populations. In this paper, we present methods to assess the contribution of genetic variants to the difference in the incidence of disease between different population groups for different scenarios. We derive expressions for the contribution of a single genetic variant, multiple genetic variants, and the contribution of the joint effect of a genetic variant and an environmental factor to the difference in the incidence of disease. The contribution of genetic variants to the difference in incidence increases with increasing difference in risk-genotype frequency, but declines with increasing difference in incidence between the two populations. The contribution of genetic variants also increases with increasing relative risk and the contribution of joint effect of genetic and environmental factors increases with increasing relative risk of the gene–environmental interaction. The contribution of genetic variants to the difference in incidence between two populations can be expressed as a function of the population attributable risks of the genetic variants in the two populations. The contribution of a group of genetic variants to the disparity in incidence of disease could change considerably by adding one more genetic variant to the group. Any estimate of genetic contribution to the disparity in incidence of disease between two populations at this stage seems to be an elusive goal. PMID:22333905

Four-component relativistic calculations in solution with the polarizable continuum model of solvation: theory, implementation, and application to the group 16 dihydrides H2X (X = O, S, Se, Te, Po).

PubMed

Remigio, Roberto Di; Bast, Radovan; Frediani, Luca; Saue, Trond

2015-05-28

We present a formulation of four-component relativistic self-consistent field (SCF) theory for a molecular solute described within the framework of the polarizable continuum model (PCM) for solvation. The linear response function for a four-component PCM-SCF state is also derived, as well as the explicit form of the additional contributions to the first-order response equations. The implementation of such a four-component PCM-SCF model, as carried out in a development version of the DIRAC program package, is documented. In particular, we present the newly developed application programming interface PCMSolver used in the actual implementation with DIRAC. To demonstrate the applicability of the approach, we present and analyze calculations of solvation effects on the geometries, electric dipole moments, and static electric dipole polarizabilities for the group 16 dihydrides H2X (X = O, S, Se, Te, Po).

The cognitive processes underlying event-based prospective memory in school-age children and young adults: a formal model-based study.

PubMed

Smith, Rebekah E; Bayen, Ute J; Martin, Claudia

2010-01-01

Fifty children 7 years of age (29 girls, 21 boys), 53 children 10 years of age (29 girls, 24 boys), and 36 young adults (19 women, 17 men) performed a computerized event-based prospective memory task. All 3 groups differed significantly in prospective memory performance, with adults showing the best performance and with 7-year-olds showing the poorest performance. We used a formal multinomial process tree model of event-based prospective memory to decompose age differences in cognitive processes that jointly contribute to prospective memory performance. The formal modeling results demonstrate that adults differed significantly from the 7-year-olds and the 10-year-olds on both the prospective component and the retrospective component of the task. The 7-year-olds and the 10-year-olds differed only in the ability to recognize prospective memory target events. The prospective memory task imposed a cost to ongoing activities in all 3 age groups. Copyright 2009 APA, all rights reserved.