Histone H4 acetylation regulates behavioral inter-individual variability in zebrafish.

PubMed

Román, Angel-Carlos; Vicente-Page, Julián; Pérez-Escudero, Alfonso; Carvajal-González, Jose M; Fernández-Salguero, Pedro M; de Polavieja, Gonzalo G

2018-04-25

Animals can show very different behaviors even in isogenic populations, but the underlying mechanisms to generate this variability remain elusive. We use the zebrafish (Danio rerio) as a model to test the influence of histone modifications on behavior. We find that laboratory and isogenic zebrafish larvae show consistent individual behaviors when swimming freely in identical wells or in reaction to stimuli. This behavioral inter-individual variability is reduced when we impair the histone deacetylation pathway. Individuals with high levels of histone H4 acetylation, and specifically H4K12, behave similarly to the average of the population, but those with low levels deviate from it. More precisely, we find a set of genomic regions whose histone H4 acetylation is reduced with the distance between the individual and the average population behavior. We find evidence that this modulation depends on a complex of Yin-yang 1 (YY1) and histone deacetylase 1 (HDAC1) that binds to and deacetylates these regions. These changes are not only maintained at the transcriptional level but also amplified, as most target regions are located near genes encoding transcription factors. We suggest that stochasticity in the histone deacetylation pathway participates in the generation of genetic-independent behavioral inter-individual variability.

Time-Structured and Net Intraindividual Variability: Tools for Examining the Development of Dynamic Characteristics and Processes

PubMed Central

Ram, Nilam; Gerstorf, Denis

2009-01-01

The study of intraindividual variability is the study of fluctuations, oscillations, adaptations, and “noise” in behavioral outcomes that manifest on micro-time scales. This paper provides a descriptive frame for the combined study of intraindividual variability and aging/development. At the conceptual level, we highlight that the study of intraindividual variability provides access to dynamic characteristics – construct-level descriptions of individuals' capacities for change (e.g., lability), and dynamic processes – the systematic changes individuals' exhibit in response to endogenous and exogenous influences (e.g., regulation). At the methodological level, we review how quantifications of net intraindividual variability (e.g., iSD) and models of time-structured intraindividual variability (e.g., time-series) are being used to measure and describe dynamic characteristics and processes. At the research design level, we point to the benefits of measurement burst study designs, wherein data are obtained across multiple time scales, for the study of development. PMID:20025395

Long-term and within-day variability of working memory performance and EEG in individuals.

PubMed

Gevins, Alan; McEvoy, Linda K; Smith, Michael E; Chan, Cynthia S; Sam-Vargas, Lita; Baum, Cliff; Ilan, Aaron B

2012-07-01

Assess individual-subject long-term and within-day variability of a combined behavioral and EEG test of working memory. EEGs were recorded from 16 adults performing n-back working memory tasks, with 10 tested in morning and afternoon sessions over several years. Participants were also tested after ingesting non-prescription medications or recreational substances. Performance and EEG measures were analyzed to derive an Overall score and three constituent sub-scores characterizing changes in performance, cortical activation, and alertness from each individual's baseline. Long-term and within-day variability were determined for each score; medication effects were assessed by reference to each individual's normal day-to-day variability. Over the several year period, the mean Overall score and sub-scores were approximately zero with standard deviations less than one. Overall scores were lower and their variability higher in afternoon relative to morning sessions. At the group level, alcohol, diphenhydramine and marijuana produced significant effects, but there were large individual differences. Objective working memory measures incorporating performance and EEG are stable over time and sensitive at the level of individual subjects to interventions that affect neurocognitive function. With further research these measures may be suitable for use in individualized medical care by providing a sensitive assessment of incipient illness and response to treatment. Published by Elsevier Ireland Ltd.

Intraindividual variability across cognitive domains: investigation of dispersion levels and performance profiles in older adults.

PubMed

Hilborn, Jennifer V; Strauss, Esther; Hultsch, David F; Hunter, Michael A

2009-05-01

A growing body of research suggests that substantial variability exists among cognitive abilities within individuals. This within-person variability across cognitive domains is termed dispersion. The present study investigated the relationship between aging and dispersion of cognitive functions both quantitatively (overall levels of dispersion) and qualitatively (patterns of dispersion) in a sample of 304 nondemented, older adults aged 64 to 92 years (M = 74.02). Quantitatively, higher levels of dispersion were observed in the old-old adults (aged 75-92 years) and those identified as having experienced cognitive decline, suggesting that dispersion level may serve as a marker of cognitive integrity. Qualitatively, three distinct dispersion profiles were identified through clustering methods, and these were found to be related to demographic, health, and performance characteristics of the individuals, suggesting that patterns of dispersion may be meaningful indicators of individual differences.

The association between social participation and cognitive function in community-dwelling older populations: Japan Gerontological Evaluation Study at Taisetsu community Hokkaido.

PubMed

Sakamoto, Ai; Ukawa, Shigekazu; Okada, Emiko; Sasaki, Sachiko; Zhao, Wenjing; Kishi, Tomoko; Kondo, Katsunori; Tamakoshi, Akiko

2017-10-01

To study the association between the number of area-level and individual-level social participation items and cognitive function in the community-dwelling older populations of three towns in Hokkaido, Japan. A survey on the frequency of social participation was mailed to those in the Japan Gerontological Evaluation Study 2013 who were aged ≥65 years, were not certified as needing long-term care, and lived in Higashikawa, Higashikagura, or Biei. A subset of participants aged 70-74 years completed the Japanese version of the Montreal Cognitive Assessment in a home visit survey. Both the area-level and individual-level social participation and demographic information were obtained on the self-administered questionnaire. A multilevel analysis using a generalized linear mixed-effects model was used to examine the association between variables in the area-level and individual-level social participation items and cognitive function. Out of 4042 respondents, data from 2576 were used in the area-level analysis. Of those, 180 were aged 70-74 years and completed the home visit survey for the individual-level analysis. A greater number of higher social participation items at the individual level was associated with higher cognitive function scores after adjusting for area-level social participation variables and confounders (regression coefficient: 0.19; 95% confidence interval: 0.03, 0.35). There were no significant associations between area-level social participation item averages and individual-level cognitive function scores. Older populations participating in many kinds of social activities exhibited preserved cognitive function even after adjusting for area-level social participation variables. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Modelling the co-evolution of indirect genetic effects and inherited variability.

PubMed

Marjanovic, Jovana; Mulder, Han A; Rönnegård, Lars; Bijma, Piter

2018-03-28

When individuals interact, their phenotypes may be affected not only by their own genes but also by genes in their social partners. This phenomenon is known as Indirect Genetic Effects (IGEs). In aquaculture species and some plants, however, competition not only affects trait levels of individuals, but also inflates variability of trait values among individuals. In the field of quantitative genetics, the variability of trait values has been studied as a quantitative trait in itself, and is often referred to as inherited variability. Such studies, however, consider only the genetic effect of the focal individual on trait variability and do not make a connection to competition. Although the observed phenotypic relationship between competition and variability suggests an underlying genetic relationship, the current quantitative genetic models of IGE and inherited variability do not allow for such a relationship. The lack of quantitative genetic models that connect IGEs to inherited variability limits our understanding of the potential of variability to respond to selection, both in nature and agriculture. Models of trait levels, for example, show that IGEs may considerably change heritable variation in trait values. Currently, we lack the tools to investigate whether this result extends to variability of trait values. Here we present a model that integrates IGEs and inherited variability. In this model, the target phenotype, say growth rate, is a function of the genetic and environmental effects of the focal individual and of the difference in trait value between the social partner and the focal individual, multiplied by a regression coefficient. The regression coefficient is a genetic trait, which is a measure of cooperation; a negative value indicates competition, a positive value cooperation, and an increasing value due to selection indicates the evolution of cooperation. In contrast to the existing quantitative genetic models, our model allows for co-evolution of IGEs and variability, as the regression coefficient can respond to selection. Our simulations show that the model results in increased variability of body weight with increasing competition. When competition decreases, i.e., cooperation evolves, variability becomes significantly smaller. Hence, our model facilitates quantitative genetic studies on the relationship between IGEs and inherited variability. Moreover, our findings suggest that we may have been overlooking an entire level of genetic variation in variability, the one due to IGEs.

Why is seed production so variable among individuals? A ten-year study with oaks reveals the importance of soil environment.

PubMed

Pérez-Ramos, Ignacio M; Aponte, Cristina; García, Luis V; Padilla-Díaz, Carmen M; Marañón, Teodoro

2014-01-01

Mast-seeding species exhibit not only a large inter-annual variability in seed production but also considerable variability among individuals within the same year. However, very little is known about the causes and consequences for population dynamics of this potentially large between-individual variability. Here, we quantified seed production over ten consecutive years in two Mediterranean oak species - the deciduous Quercus canariensis and the evergreen Q. suber - that coexist in forests of southern Spain. First, we calibrated likelihood models to identify which abiotic and biotic variables best explain the magnitude (hereafter seed productivity) and temporal variation of seed production at the individual level (hereafter CVi), and infer whether reproductive effort results from the available soil resources for the plant or is primarily determined by selectively favoured strategies. Second, we explored the contribution of between-individual variability in seed production as a potential mechanism of satiation for predispersal seed predators. We found that Q. canariensis trees inhabiting moister and more fertile soils were more productive than those growing in more resource-limited sites. Regarding temporal variation, individuals of the two studied oak species inhabiting these resource-rich environments also exhibited larger values of CVi. Interestingly, we detected a satiating effect on granivorous insects at the tree level in Q. suber, which was evident in those years where between-individual variability in acorn production was higher. These findings suggest that individual seed production (both in terms of seed productivity and inter-annual variability) is strongly dependent on soil resource heterogeneity (at least for one of the two studied oak species) with potential repercussions for recruitment and population dynamics. However, other external factors (such as soil heterogeneity in pathogen abundance) or certain inherent characteristics of the tree might be also involved in this process.

What carries a mediation process? Configural analysis of mediation.

PubMed

von Eye, Alexander; Mun, Eun Young; Mair, Patrick

2009-09-01

Mediation is a process that links a predictor and a criterion via a mediator variable. Mediation can be full or partial. This well-established definition operates at the level of variables even if they are categorical. In this article, two new approaches to the analysis of mediation are proposed. Both of these approaches focus on the analysis of categorical variables. The first involves mediation analysis at the level of configurations instead of variables. Thus, mediation can be incorporated into the arsenal of methods of analysis for person-oriented research. Second, it is proposed that Configural Frequency Analysis (CFA) can be used for both exploration and confirmation of mediation relationships among categorical variables. The implications of using CFA are first that mediation hypotheses can be tested at the level of individual configurations instead of variables. Second, this approach leaves the door open for different types of mediation processes to exist within the same set. Using a data example, it is illustrated that aggregate-level analysis can overlook mediation processes that operate at the level of individual configurations.

Individual exposure estimates may be erroneous when spatiotemporal variability of air pollution and human mobility are ignored.

PubMed

Park, Yoo Min; Kwan, Mei-Po

2017-01-01

This study aims to empirically demonstrate the necessity to consider both the spatiotemporal variability of air pollution and individual daily movement patterns in exposure and health risk assessment. It compares four different types of exposure estimates generated by using (1) individual movement data and hourly air pollution concentrations; (2) individual movement data and daily average air pollution data; (3) residential location and hourly pollution levels; and (4) residential location and daily average pollution data. These four estimates are significantly different, which supports the argument that ignoring the spatiotemporal variability of environmental risk factors and human mobility may lead to misleading results in exposure assessment. Additionally, three-dimensional (3D) geovisualization presented in the paper shows how person-specific space-time context is generated by the interactions between air pollution and an individual, and how the different individualized contexts place individuals at different levels of health risk. Copyright © 2016 Elsevier Ltd. All rights reserved.

Age and Sex Differences in Intra-Individual Variability in a Simple Reaction Time Task

ERIC Educational Resources Information Center

Ghisletta, Paolo; Renaud, Olivier; Fagot, Delphine; Lecerf, Thierry; de Ribaupierre, Anik

2018-01-01

While age effects in reaction time (RT) tasks across the lifespan are well established for level of performance, analogous findings have started appearing also for indicators of intra-individual variability (IIV). Children are not only slower, but also display more variability than younger adults in RT. Yet, little is known about potential…

Multilevel built environment features and individual odds of overweight and obesity in Utah

PubMed Central

Xu, Yanqing; Wen, Ming; Wang, Fahui

2015-01-01

Based on the data from the Behavioral Risk Factor Surveillance System (BRFSS) in 2007, 2009 and 2011 in Utah, this research uses multilevel modeling (MLM) to examine the associations between neighborhood built environments and individual odds of overweight and obesity after controlling for individual risk factors. The BRFSS data include information on 21,961 individuals geocoded to zip code areas. Individual variables include BMI (body mass index) and socio-demographic attributes such as age, gender, race, marital status, education attainment, employment status, and whether an individual smokes. Neighborhood built environment factors measured at both zip code and county levels include street connectivity, walk score, distance to parks, and food environment. Two additional neighborhood variables, namely the poverty rate and urbanicity, are also included as control variables. MLM results show that at the zip code level, poverty rate and distance to parks are significant and negative covariates of the odds of overweight and obesity; and at the county level, food environment is the sole significant factor with stronger fast food presence linked to higher odds of overweight and obesity. These findings suggest that obesity risk factors lie in multiple neighborhood levels and built environment features need to be defined at a neighborhood size relevant to residents' activity space. PMID:26251559

Job Loss: An Individual Level Review and Model.

ERIC Educational Resources Information Center

DeFrank, Richard S.; Ivancevich, John M.

1986-01-01

Reviews behavioral, medical, and social science literature to illustrate the complexity and multidisciplinary nature of the job loss experience and provides a conceptual model to examine individual responses to job loss. Emphasizes the importance of including organizational-relevant variables in individual level conceptualizations and proposed…

Intraindividual variability in cognitive performance in older adults: comparison of adults with mild dementia, adults with arthritis, and healthy adults.

PubMed

Hultsch, D F; MacDonald, S W; Hunter, M A; Levy-Bencheton, J; Strauss, E

2000-10-01

Intraindividual variability in latency and accuracy of cognitive performance across both trials and occasions was examined in 3 groups of older adults: healthy adults, adults with arthritis, and adults diagnosed with mild dementia. Participants completed 2 reaction-time and 2 episodic-memory tasks on 4 occasions. Results indicated that intraindividual variability in latency was greater in individuals diagnosed with mild dementia than in adults who were neurologically intact, regardless of their health status. Individual differences in variability were stable over time and across cognitive domains. Intraindividual variability was also related to level of performance and was uniquely predictive of neurological status, independent of level of performance. Results suggest that intraindividual variability may be a behavioral indicator of compromised neurological mechanisms.

Developmental differences in intra-individual variability in children with ADHD and ASD.

PubMed

van Belle, Janna; van Hulst, Branko M; Durston, Sarah

2015-12-01

Intra-individual variability reflects temporal variation within an individual's performance on a cognitive task. Children with developmental disorders, such as ADHD and ASD show increased levels of intra-individual variability. In typical development, intra-individual variability decreases sharply between the ages 6 and 20. The tight link between intra-individual variability and age has led to the suggestion that it may be marker of neural development. As there is accumulating evidence that ADHD and ASD are characterised by atypical neurodevelopmental trajectories, we set out to explore developmental changes in intra-individual variability in subjects with ADHD and ASD. We used propensity score matching to match a cross-sectional sample of children with ADHD, ASD and control subjects (N = 405, aged 6-19 years old) for age, IQ and gender. We used ex-Gaussian distribution parameters to characterise intra-individual variability on fast responses (sigma) and slow responses (tau). Results showed that there was a similar decrease in mean response times with age across groups, and an interaction between age and group for measures of variability, where there was a much lower rate of change in the variability parameters (sigma and tau) for subjects with ASD compared with the other two groups. Subjects with ADHD had higher intra-individual variability, reflected by both sigma and tau, but the rate of decrease in variability with age was similar to that of the controls. These results suggest that subjects with ADHD, ASD and controls differ in the rate at which intra-individual variability decreases during development, and support the idea that intra-individual variability may be a marker of neural development, mimicking the neurodevelopmental changes in these disorders. © 2015 Association for Child and Adolescent Mental Health.

Individual and Institutional Components of the Medical School Educational Environment.

PubMed

Gruppen, Larry D; Stansfield, R Brent

2016-11-01

To examine, using a systems framework, the relative influence of individual-level and institution-level factors on student perceptions of the medical school educational environment. A series of hierarchical linear models were fit to a large, 18-school longitudinal dataset of student perceptions of the educational environment, various demographics, and student empathy, tolerance of ambiguity, coping, and patient-provider orientation. Separate models were evaluated for individual-level factors alone, institution-level factors alone, and the combination of individual- and institution-level factors. The individual-level model accounted for 56.7% of the variance in student perceptions of the educational environment. However, few specific variables at the individual level had noteworthy direct effects on these perceptions. Similarly, the institution-level model accounted for 10.3% of the variance in student perceptions, but the specific characteristics of the institution explained little of this impact. The combined individual- and institution-level model attributed 45.5% of the variance in student perceptions to individual-level factors and 10.8% to institution-level factors. Again, specific variables explained little of this impact. These findings indicate that the impact of individual-level factors on perceptions of the educational environment is about four times greater than institution-level factors. This contrast reflects the fact that the educational environment is defined through a learner, not institutional lens. Nonetheless, institutions vary in learner perceptions of their environments, and these differences may provide some support for institutional initiatives to improve the educational environment. More broadly, these results evidence the complexity of the educational environment, both in defining it and in understanding its dynamics.

Output variability across animals and levels in a motor system

PubMed Central

Norris, Brian J; Günay, Cengiz; Kueh, Daniel

2018-01-01

Rhythmic behaviors vary across individuals. We investigated the sources of this output variability across a motor system, from the central pattern generator (CPG) to the motor plant. In the bilaterally symmetric leech heartbeat system, the CPG orchestrates two coordinations in the bilateral hearts with different intersegmental phase relations (Δϕ) and periodic side-to-side switches. Population variability is large. We show that the system is precise within a coordination, that differences in repetitions of a coordination contribute little to population output variability, but that differences between bilaterally homologous cells may contribute to some of this variability. Nevertheless, much output variability is likely associated with genetic and life history differences among individuals. Variability of Δϕ were coordination-specific: similar at all levels in one, but significantly lower for the motor pattern than the CPG pattern in the other. Mechanisms that transform CPG output to motor neurons may limit output variability in the motor pattern. PMID:29345614

Impact of marriage on HIV/AIDS risk behaviors among impoverished, at-risk couples: a multilevel latent variable approach.

PubMed

Stein, Judith A; Nyamathi, Adeline; Ullman, Jodie B; Bentler, Peter M

2007-01-01

Studies among normative samples generally demonstrate a positive impact of marriage on health behaviors and other related attitudes. In this study, we examine the impact of marriage on HIV/AIDS risk behaviors and attitudes among impoverished, highly stressed, homeless couples, many with severe substance abuse problems. A multilevel analysis of 368 high-risk sexually intimate married and unmarried heterosexual couples assessed individual and couple-level effects on social support, substance use problems, HIV/AIDS knowledge, perceived HIV/AIDS risk, needle-sharing, condom use, multiple sex partners, and HIV/AIDS testing. More variance was explained in the protective and risk variables by couple-level latent variable predictors than by individual latent variable predictors, although some gender effects were found (e.g., more alcohol problems among men). The couple-level variable of marriage predicted lower perceived risk, less deviant social support, and fewer sex partners but predicted more needle-sharing.

A multilevel perspective to explain recycling behaviour in communities.

PubMed

Tabernero, Carmen; Hernández, Bernardo; Cuadrado, Esther; Luque, Bárbara; Pereira, Cícero R

2015-08-15

Previous research on the motivation for environmentally responsible behaviour has focused mainly on individual variables, rather than organizational or collective variables. Therefore, the results of those studies are hardly applicable to environmental management. This study considers individual, collective, and organizational variables together that contribute to the management of environmental waste. The main aim is to identify, through the development of a multilevel model, those predictive variables of recycling behaviour that help organizations to increase the recycling rates in their communities. Individual (age, gender, educational level, self-efficacy with respect to residential recycling, individual recycling behaviour), organizational (satisfaction with the quality of the service provided by a recycling company), and collective (community recycling rates, number of inhabitants, community efficacy beliefs) motivational factors relevant to recycling behaviour were analysed. A sample of 1501 residents from 55 localities was surveyed. The results of multilevel analyses indicated that there was significant variability within and between localities. Interactions between variables at the level of the individual (e.g. satisfaction with service quality) and variables at the level of the collective (e.g. community efficacy) predicted recycling behaviour in localities with low and high community recycling rates and large and small populations. The interactions showed that the relationship between self-efficacy and recycling is stronger in localities with weak community efficacy beliefs than in communities with strong beliefs. The findings show that the relationship between satisfaction with service quality and recycling behaviour is stronger in localities with strong community efficacy beliefs than in communities with weaker beliefs and a smaller population. The results are discussed accordingly in relation to theory and possible contribution to waste management. Those findings may be incorporated in national and international environmental policies in order to promote environmentally responsible behaviour in citizenship. Copyright © 2015 Elsevier Ltd. All rights reserved.

Social determinants of dental treatment needs in Brazilian adults.

PubMed

Roncalli, Angelo Giuseppe; Tsakos, Georgios; Sheiham, Aubrey; de Souza, Georgia Costa; Watt, Richard G

2014-10-23

The chronic cumulative nature of caries makes treatment needs a severe problem in adults. Despite the fact that oral diseases occur in social contexts, there are few studies using multilevel analyses focusing on treatment needs. Thus, considering the importance of context in explaining oral health related inequalities, this study aims to evaluate the social determinants of dental treatment needs in 35-44 year old Brazilian adults, assessing whether inequalities in needs are expressed at individual and contextual levels. The dependent variables were based on the prevalence of normative dental treatment needs in adults: (a) restorative treatment; (b) tooth extraction and (c) prosthetic treatment. The independent variables at first level were household income, formal education level, sex and race. At second level, income, sanitation, infrastructure and house conditions. The city-level variables were the Human Development Index (HDI) and indicators related to health services. Exploratory analysis was performed evaluating the effect of each level through calculating Prevalence Ratios (PR). In addition, a three-level multilevel modelling was constructed for all outcomes to verify the effect of individual characteristics and also the influence of context. In relation to the need for restorative treatment, the main factors implicated were related to individual socioeconomic position, however the city-level contextual effect should also be considered. Regarding need for tooth extraction, the contextual effect does not seem to be important and, in relation to the needs for prosthetic treatment, the final model showed effect of individual-level and city-level. Variables related to health services did not show significant effects. Dental treatment needs related to primary care (restoration and tooth extraction) and secondary care (prosthesis) were strongly associated with individual socioeconomic position, mainly income and education, in Brazilian adults. In addition to this individual effect, a city-level contextual effect, represented by HDI, was also observed for need for restorations and prosthesis, but not for tooth extractions. These findings have important implications for the health policy especially for financing and planning, since the distribution of oral health resources must consider the inequalities in availability and affordability of dental care for all.

Macro- and micro-level predictors of age categorization: results from the European Social Survey.

PubMed

Ayalon, Liat; Doron, Israel; Bodner, Ehud; Inbar, Noit

2014-03-01

This study evaluated macro- and micro-level variables associated with individuals' perception of the ending of youth, the beginning of old age, and the length of the middle age period. The European Social Survey is a biennial multi-country, cross-sectional survey. Our analysis is based on the fourth wave, which included a rotating module on ageism. The source sample consisted of 28 countries and a total of 54,988 respondents. Whereas macro-level variability accounted for 14 % of the variance associated with the perception of the ending of youth, only 5.7 % of the variance associated with the perception of the beginning of old age was accounted for by macro-level variability. Almost 10 % of the variance associated with the perception of the middle age period was associated with macro-level variability. Different patterns of macro- and micro-level correlates emerged for the ending of youth, beginning of old age, and the period of middle age. Overall, results demonstrate that individual differences in the perception of the ending of youth, the beginning of old age, and the length of the middle age period are more pronounced than contextual differences. Results also suggest that individuals' mental maps regarding the timing of these events are not necessarily concordant.

Variability, Constraints, and Creativity: Shedding Light on Claude Monet.

ERIC Educational Resources Information Center

Stokes, Patricia D.

2001-01-01

Discusses how creative individuals maintain high levels of variability, examining how Claude Monet's habitually high level of variability in painting was acquired during his childhood and early apprenticeship and maintained throughout his adult career by a continuous series of task constraints imposed by the artist on his own work. For Monet,…

Integrating plant ecological responses to climate extremes from individual to ecosystem levels.

PubMed

Felton, Andrew J; Smith, Melinda D

2017-06-19

Climate extremes will elicit responses from the individual to the ecosystem level. However, only recently have ecologists begun to synthetically assess responses to climate extremes across multiple levels of ecological organization. We review the literature to examine how plant responses vary and interact across levels of organization, focusing on how individual, population and community responses may inform ecosystem-level responses in herbaceous and forest plant communities. We report a high degree of variability at the individual level, and a consequential inconsistency in the translation of individual or population responses to directional changes in community- or ecosystem-level processes. The scaling of individual or population responses to community or ecosystem responses is often predicated upon the functional identity of the species in the community, in particular, the dominant species. Furthermore, the reported stability in plant community composition and functioning with respect to extremes is often driven by processes that operate at the community level, such as species niche partitioning and compensatory responses during or after the event. Future research efforts would benefit from assessing ecological responses across multiple levels of organization, as this will provide both a holistic and mechanistic understanding of ecosystem responses to increasing climatic variability.This article is part of the themed issue 'Behavioural, ecological and evolutionary responses to extreme climatic events'. © 2017 The Author(s).

Individual- and area-level characteristics associated with alcohol-related mortality among adult Lithuanian males: A multilevel analysis based on census-linked data.

PubMed

Grigoriev, Pavel; Jasilionis, Domantas; Stumbrys, Daumantas; Stankūnienė, Vladislava; Shkolnikov, Vladimir M

2017-01-01

Although excessive alcohol-related mortality in the post-Soviet countries remains the major public health threat, determinants of this phenomenon are still poorly understood. We assess simultaneously individual- and area-level factors associated with an elevated risk of alcohol-related mortality among Lithuanian males aged 30-64. Our analysis is based on a census-linked dataset containing information on individual- and area-level characteristics and death events which occurred between March 1st, 2011 and December 31st, 2013. We limit the analysis to a few causes of death which are directly linked to excessive alcohol consumption: accidental poisonings by alcohol (X45) and liver cirrhosis (K70 and K74). Multilevel Poisson regression models with random intercepts are applied to estimate mortality rate ratios (MRR). The selected individual-level characteristics are important predictors of alcohol-related mortality, whereas area-level variables show much less pronounced or insignificant effects. Compared to married men, never married (MRR = 1.9, CI:1.6-2.2), divorced (MRR = 2.6, CI:2.3-2.9), and widowed (MRR = 2.4, CI: 1.8-3.1) men are disadvantaged groups. Men who have the lowest level of educational attainment have the highest mortality risk (MRR = 1.7 CI:1.4-2.1). Being unemployed is associated with a five-fold risk of alcohol-related death (MRR = 5.1, CI: 4.4-5.9), even after adjusting for all other individual variables. Lithuanian males have an advantage over Russian (MRR = 1.3, CI:1.1-1.6) and Polish (MRR = 1.8, CI: 1.5-2.2) males. After adjusting for all individual characteristics, only two out of seven area-level variables-i.e., the share of ethnic minorities in the population and the election turnout-have statistically significant direct associations. These variables contribute to a higher risk of alcohol-related mortality at the individual level. The huge and increasing socio-economic disparities in alcohol-related mortality indicate that recently implemented anti-alcohol measures in Lithuania should be reinforced by specific measures targeting the most disadvantaged population groups and geographical areas.

Spin, Unit Climate, and Aggression: Near Term, Long Term, and Reciprocal Predictors of Violence Among Workers in Military Settings

DTIC Science & Technology

2015-08-01

exposure to aggression (e.g., drug / alcohol use, burnout , suicidal ideation). The proposed effort includes both individual level variables (e.g...aggression (e.g., drug / alcohol use, burnout , suicidal ideation). The proposed effort includes both individual level variables (e.g., differences in...anger / rage, bullying, harassment, intimate partner violence) and related physical health and mental health concerns (e.g., drug / alcohol use, burnout

Human Responses to Climate Variability: The Case of South Africa

NASA Astrophysics Data System (ADS)

Oppenheimer, M.; Licker, R.; Mastrorillo, M.; Bohra-Mishra, P.; Estes, L. D.; Cai, R.

2014-12-01

Climate variability has been associated with a range of societal and individual outcomes including migration, violent conflict, changes in labor productivity, and health impacts. Some of these may be direct responses to changes in mean temperature or precipitation or extreme events, such as displacement of human populations by tropical cyclones. Others may be mediated by a variety of biological, social, or ecological factors such as migration in response to long-term changes in crops yields. Research is beginning to elucidate and distinguish the many channels through which climate variability may influence human behavior (ranging from the individual to the collective, societal level) in order to better understand how to improve resilience in the face of current variability as well as future climate change. Using a variety of data sets from South Africa, we show how climate variability has influenced internal (within country) migration in recent history. We focus on South Africa as it is a country with high levels of internal migration and dramatic temperature and precipitation changes projected for the 21st century. High poverty rates and significant levels of rain-fed, smallholder agriculture leave large portions of South Africa's population base vulnerable to future climate change. In this study, we utilize two complementary statistical models - one micro-level model, driven by individual and household level survey data, and one macro-level model, driven by national census statistics. In both models, we consider the effect of climate on migration both directly (with gridded climate reanalysis data) and indirectly (with agricultural production statistics). With our historical analyses of climate variability, we gain insights into how the migration decisions of South Africans may be influenced by future climate change. We also offer perspective on the utility of micro and macro level approaches in the study of climate change and human migration.

Sentence comprehension in agrammatic aphasia: history and variability to clinical implications.

PubMed

Johnson, Danielle; Cannizzaro, Michael S

2009-01-01

Individuals with Broca's aphasia often present with deficits in their ability to comprehend non-canonical sentences. This has been contrastingly characterized as a systematic loss of specific grammatical abilities or as individual variability in the dynamics between processing load and resource availability. The present study investigated sentence level comprehension in participants with Broca's aphasia in an attempt to integrate these contrasting views into a clinically useful process. Two participants diagnosed with Broca's aphasia were assessed using a sentence-to-picture matching paradigm and a truth-value judgement task, across sentence constructions thought to be problematic for this population. The data demonstrate markedly different patterns of performance between participants, as well as variability within participants (e.g. by sentence type). These findings support the notion of individual performance variability in persons with aphasia. Syntactic theory was instructive for assessing sentence level comprehension, leading to a clinically relevant process of identifying treatment targets considering both performance variability and syntactic complexity for this population.

Readability Level of Standardized Test Items and Student Performance: The Forgotten Validity Variable

ERIC Educational Resources Information Center

Hewitt, Margaret A.; Homan, Susan P.

2004-01-01

Test validity issues considered by test developers and school districts rarely include individual item readability levels. In this study, items from a major standardized test were examined for individual item readability level and item difficulty. The Homan-Hewitt Readability Formula was applied to items across three grade levels. Results of…

Characterizing Individual Differences in Functional Connectivity Using Dual-Regression and Seed-Based Approaches

PubMed Central

Smith, David V.; Utevsky, Amanda V.; Bland, Amy R.; Clement, Nathan; Clithero, John A.; Harsch, Anne E. W.; Carter, R. McKell; Huettel, Scott A.

2014-01-01

A central challenge for neuroscience lies in relating inter-individual variability to the functional properties of specific brain regions. Yet, considerable variability exists in the connectivity patterns between different brain areas, potentially producing reliable group differences. Using sex differences as a motivating example, we examined two separate resting-state datasets comprising a total of 188 human participants. Both datasets were decomposed into resting-state networks (RSNs) using a probabilistic spatial independent components analysis (ICA). We estimated voxelwise functional connectivity with these networks using a dual-regression analysis, which characterizes the participant-level spatiotemporal dynamics of each network while controlling for (via multiple regression) the influence of other networks and sources of variability. We found that males and females exhibit distinct patterns of connectivity with multiple RSNs, including both visual and auditory networks and the right frontal-parietal network. These results replicated across both datasets and were not explained by differences in head motion, data quality, brain volume, cortisol levels, or testosterone levels. Importantly, we also demonstrate that dual-regression functional connectivity is better at detecting inter-individual variability than traditional seed-based functional connectivity approaches. Our findings characterize robust—yet frequently ignored—neural differences between males and females, pointing to the necessity of controlling for sex in neuroscience studies of individual differences. Moreover, our results highlight the importance of employing network-based models to study variability in functional connectivity. PMID:24662574

Do changes in grazing pressure and the degree of shrub encroachment alter the effects of individual shrubs on understorey plant communities and soil function?

PubMed

Soliveres, Santiago; Eldridge, David J

2014-04-01

Shrub canopies in semi-arid environments often produce positive effects on soil fertility, and on the richness and biomass of understorey plant communities. However, both positive and negative effects of shrub encroachment on plant and soil attributes have been reported at the landscape-level. The contrasting results between patch- and landscape-level effects in shrublands could be caused by differences in the degree of shrub encroachment or grazing pressure, both of which are likely to reduce the ability of individual shrubs to ameliorate their understorey environment.We examined how grazing and shrub encroachment (measured as landscape-level shrub cover) influence patch-level effects of shrubs on plant density, biomass and similarity in species composition between shrub understories and open areas, and on soil stability, nutrient cycling, and infiltration in two semi-arid Australian woodlands.Individual shrubs had consistently positive effects on all plant and soil variables (average increase of 23% for all variables). These positive patch-level effects persisted with increasing shrub cover up to our maximum of 50% cover. Heavy grazing negatively affected most of the variables studied (average decline of 11%). It also altered, for some variables, how individual shrubs affected their sub-canopy environment with increasing shrub cover. Thus for species density, biomass and soil infiltration, the positive effect of individual shrubs with increasing shrub cover diminished under heavy grazing. Our study refines predictions of the effects of woody encroachment on ecosystem structure and functioning by showing that heavy grazing, rather than differences in shrub cover, explains the contrasting effects on ecosystem structure and function between individual shrubs and those in dense aggregations. We also discuss how species-specific traits of the encroaching species, such as their height or its ability to fix N, might influence the relationship between their patch-level effects and their cover within the landscape.

Do changes in grazing pressure and the degree of shrub encroachment alter the effects of individual shrubs on understorey plant communities and soil function?

PubMed Central

Soliveres, Santiago; Eldridge, David J.

2015-01-01

Summary Shrub canopies in semi-arid environments often produce positive effects on soil fertility, and on the richness and biomass of understorey plant communities. However, both positive and negative effects of shrub encroachment on plant and soil attributes have been reported at the landscape-level. The contrasting results between patch- and landscape-level effects in shrublands could be caused by differences in the degree of shrub encroachment or grazing pressure, both of which are likely to reduce the ability of individual shrubs to ameliorate their understorey environment. We examined how grazing and shrub encroachment (measured as landscape-level shrub cover) influence patch-level effects of shrubs on plant density, biomass and similarity in species composition between shrub understories and open areas, and on soil stability, nutrient cycling, and infiltration in two semi-arid Australian woodlands. Individual shrubs had consistently positive effects on all plant and soil variables (average increase of 23% for all variables). These positive patch-level effects persisted with increasing shrub cover up to our maximum of 50% cover. Heavy grazing negatively affected most of the variables studied (average decline of 11%). It also altered, for some variables, how individual shrubs affected their sub-canopy environment with increasing shrub cover. Thus for species density, biomass and soil infiltration, the positive effect of individual shrubs with increasing shrub cover diminished under heavy grazing. Synthesis Our study refines predictions of the effects of woody encroachment on ecosystem structure and functioning by showing that heavy grazing, rather than differences in shrub cover, explains the contrasting effects on ecosystem structure and function between individual shrubs and those in dense aggregations. We also discuss how species-specific traits of the encroaching species, such as their height or its ability to fix N, might influence the relationship between their patch-level effects and their cover within the landscape. PMID:25914435

For whom is income inequality most harmful? A multi-level analysis of income inequality and mortality in Norway.

PubMed

Dahl, Espen; Ivar Elstad, Jon; Hofoss, Dag; Martin-Mollard, Melissa

2006-11-01

This study investigates the degree to which contextual income inequality in economic regions in Norway affected mortality during the 1990s, above the effects of mean regional income and individual-level confounders. A further objective is to explore whether income inequality effects on mortality differed between socioeconomic groups. Data were constructed by linkages of administrative registers encompassing all Norwegian inhabitants. The outcome variable was all-cause mortality during 6 years (i.e., died 1994-1999 or alive end of 1999). Men and women aged 25-66 in 1993 were analysed. Regions' mean income and income inequality (in terms of gini coefficients) were calculated from consumption-units-adjusted family disposable income. Individual-level variables included sex, age, marital status, individual income, education, and being a recipient of health-related welfare benefits. Multilevel logistic regression models were fitted for 2,197,231 individuals nested within 88 regions. After adjusting for regional mean income and individual-level variables, the odds ratio (OR) for mortality 1994-1999 was 1.028 (95% CI 1.023-1.033) on the gini variable multiplied by 100. Analyses of cross-level interactions indicated some, albeit modest, income inequality effects on mortality in the upper income and educational categories. Among those with low individual income, low education, and among recipients of health-related welfare benefits, mortality effects of higher regional income inequality were significantly stronger than among those more advantageously placed in the social structure. The results of this study differ from previous studies which have suggested that contextual income inequality has a minor impact on population health in egalitarian countries. The results indicate that in Norway, neither a comparatively egalitarian income distribution nor generous and comprehensive welfare institutions hindered the emergence of regional-level income inequality effects on mortality, and these effects were particularly marked among socioeconomically disadvantaged groups. Explanations for the results are discussed.

The Influence of Individual Variability on Zooplankton Population Dynamics under Different Environmental Conditions

NASA Astrophysics Data System (ADS)

Bi, R.; Liu, H.

2016-02-01

Understanding how biological components respond to environmental changes could be insightful to predict ecosystem trajectories under different climate scenarios. Zooplankton are key components of marine ecosystems and changes in their dynamics could have major impact on ecosystem structure. We developed an individual-based model of a common coastal calanoid copepod Acartia tonsa to examine how environmental factors affect zooplankton population dynamics and explore the role of individual variability in sustaining population under various environmental conditions consisting of temperature, food concentration and salinity. Total abundance, egg production and proportion of survival were used to measure population success. Results suggested population benefits from high level of individual variability under extreme environmental conditions including unfavorable temperature, salinity, as well as low food concentration, and selection on fast-growers becomes stronger with increasing individual variability and increasing environmental stress. Multiple regression analysis showed that temperature, food concentration, salinity and individual variability have significant effects on survival of A. tonsa population. These results suggest that environmental factors have great influence on zooplankton population, and individual variability has important implications for population survivability under unfavorable conditions. Given that marine ecosystems are at risk from drastic environmental changes, understanding how individual variability sustains populations could increase our capability to predict population dynamics in a changing environment.

Association of suicide rates, gun ownership, conservatism and individual suicide risk.

PubMed

Kposowa, Augustine J

2013-09-01

The purpose of the study was to examine the association of suicide rates, firearm ownership, political conservatism, religious integration at the state level, and individual suicide risk. Social structural and social learning and social integration theories were theoretical frameworks employed. It was hypothesized that higher suicide rates, higher state firearm availability, and state conservatism elevate individual suicide risk. Data were pooled from the Multiple Cause of Death Files. Multilevel logistic regression models were fitted to all deaths occurring in 2000 through 2004 by suicide. The state suicide rate significantly elevated individual suicide risk (AOR = 1.042, CI = 1.037, 1.046). Firearm availability at the state level was associated with significantly higher odds of individual suicide (AOR = 1.004, CI = 1.003, 1.006). State political conservatism elevated the odds of individual suicides (AOR = 1.005, CI = 1.003, 1.007), while church membership at the state level reduced individual odds of suicide (AOR = 0.995, CI = 0.993, 0.996). The results held even after controlling for socioeconomic and demographic variables at the individual level. It was concluded that the observed association between individual suicide odds and national suicide rates, and firearm ownership cannot be discounted. Future research ought to focus on integrating individual level data and contextual variables when testing for the impact of firearm ownership. Support was found for social learning and social integration theories.

Measuring performance in virtual reality phacoemulsification surgery

NASA Astrophysics Data System (ADS)

Söderberg, Per; Laurell, Carl-Gustaf; Simawi, Wamidh; Skarman, Eva; Nordh, Leif; Nordqvist, Per

2008-02-01

We have developed a virtual reality (VR) simulator for phacoemulsification surgery. The current work aimed at developing a relative performance index that characterizes the performance of an individual trainee. We recorded measurements of 28 response variables during three iterated surgical sessions in 9 experienced cataract surgeons, separately for the sculpting phase and the evacuation phase of phacoemulsification surgery and compared their outcome to that of a reference group of naive trainees. We defined an individual overall performance index, an individual class specific performance index and an individual variable specific performance index. We found that on an average the experienced surgeons performed at a lower level than a reference group of naive trainees but that this was particularly attributed to a few surgeons. When their overall performance index was further analyzed as class specific performance index and variable specific performance index it was found that the low level performance was attributed to a behavior that is acceptable for an experienced surgeon but not for a naive trainee. It was concluded that relative performance indices should use a reference group that corresponds to the measured individual since the definition of optimal surgery may vary among trainee groups depending on their level of experience.

Symptom variability, affect and physical activity in ambulatory persons with multiple sclerosis: Understanding patterns and time-bound relationships.

PubMed

Kasser, Susan L; Goldstein, Amanda; Wood, Phillip K; Sibold, Jeremy

2017-04-01

Individuals with multiple sclerosis (MS) experience a clinical course that is highly variable with daily fluctuations in symptoms significantly affecting functional ability and quality of life. Yet, understanding how MS symptoms co-vary and associate with physical and psychological health is unclear. The purpose of the study was to explore variability patterns and time-bound relationships across symptoms, affect, and physical activity in individuals with MS. The study employed a multivariate, replicated, single-subject repeated-measures (MRSRM) design and involved four individuals with MS. Mood, fatigue, pain, balance confidence, and losses of balance were measured daily over 28 days by self-report. Physical activity was also measured daily over this same time period via accelerometry. Dynamic factor analysis (DFA) was used to determine the dimensionality and lagged relationships across the variables. Person-specific models revealed considerable time-dependent co-variation patterns as well as pattern variation across subjects. Results also offered insight into distinct variability structures at varying levels of disability. Modeling person-level variability may be beneficial for addressing the heterogeneity of experiences in individuals with MS and for understanding temporal and dynamic interrelationships among perceived symptoms, affect, and health outcomes in this group. Copyright © 2016 Elsevier Inc. All rights reserved.

Investigating systematic individual differences in sleep-deprived performance on a high-fidelity flight simulator.

PubMed

Van Dongen, Hans P A; Caldwell, John A; Caldwell, J Lynn

2006-05-01

Laboratory research has revealed considerable systematic variability in the degree to which individuals' alertness and performance are affected by sleep deprivation. However, little is known about whether or not different populations exhibit similar levels of individual variability. In the present study, we examined individual variability in performance impairment due to sleep loss in a highly select population of militaryjet pilots. Ten active-duty F-117 pilots were deprived of sleep for 38 h and studied repeatedly in a high-fidelity flight simulator. Data were analyzed with a mixed-model ANOVA to quantify individual variability. Statistically significant, systematic individual differences in the effects of sleep deprivation were observed, even when baseline differences were accounted for. The findings suggest that highly select populations may exhibit individual differences in vulnerability to performance impairment from sleep loss just as the general population does. Thus, the scientific and operational communities' reliance on group data as opposed to individual data may entail substantial misestimation of the impact of job-related stressors on safety and performance.

The neighbourhood effects of geographical access to tobacco retailers on individual smoking behaviour.

PubMed

Pearce, J; Hiscock, R; Moon, G; Barnett, R

2009-01-01

To investigate whether neighbourhood measures of geographical accessibility to outlets selling tobacco (supermarkets, convenience stores and petrol stations) are associated with individual smoking behaviour in New Zealand. Using geographical information systems, travel times from the population-weighted centroid of each neighbourhood to the closest outlet selling tobacco were calculated for all 38,350 neighbourhoods across New Zealand. These measures were appended to the 2002/03 New Zealand Health Survey, a national survey of 12, 529 adults. Two-level logistic regression models were fitted to examine the effects of neighbourhood locational access upon individual smoking behaviour after controlling for potential individual- and neighbourhood-level confounding factors, including deprivation and urban/rural status. After controlling for individual-level demographic and socioeconomic variables, individuals living in the quartiles of neighbourhoods with the best access to supermarkets (OR 1.23, 95% CI 1.06 to 1.42) and convenience stores (OR 1.19, 95% CI 1.03 to 1.38) had a higher odds of smoking compared with individuals in the worst access quartiles. However, the association between neighbourhood accessibility to supermarkets and convenience stores was not apparent once other neighbourhood-level variables (deprivation and rurality) were included. At the national level, there is little evidence to suggest that, after adjustment for neighbourhood deprivation, better locational access to tobacco retail provision in New Zealand is associated with individual-level smoking behaviour.

Why Do We Stay? Career Rural Teachers' Burnout Compared to Personal Motivational Sources and Demographics

ERIC Educational Resources Information Center

Bell, David J.

2010-01-01

This study investigated the effects of individual motivational sources, demographics, and levels of burnout within career rural school teachers in Nebraska. The dependent variable was the psychological syndrome burnout as measured by the Maslach Burnout Inventory. Two independent variables were individual motivational sources (a personality trait…

Team-level predictors of innovation at work: a comprehensive meta-analysis spanning three decades of research.

PubMed

Hülsheger, Ute R; Anderson, Neil; Salgado, Jesus F

2009-09-01

This article presents a meta-analysis of team-level antecedents of creativity and innovation in the workplace. Using a general input-process-output model, the authors examined 15 team-level variables researched in primary studies published over the last 30 years and their relation to creativity and innovation. An exhaustive search of the international innovation literature resulted in a final sample (k) of 104 independent studies. Results revealed that team process variables of support for innovation, vision, task orientation, and external communication displayed the strongest relationships with creativity and innovation (rhos between 0.4 and 0.5). Input variables (i.e., team composition and structure) showed weaker effect sizes. Moderator analyses confirmed that relationships differ substantially depending on measurement method (self-ratings vs. independent ratings of innovation) and measurement level (individual vs. team innovation). Team variables displayed considerably stronger relationships with self-report measures of innovation compared with independent ratings and objective criteria. Team process variables were more strongly related to creativity and innovation measured at the team than the individual level. Implications for future research and pragmatic ramifications for organizational practice are discussed in conclusion.

Belief in Family Planning Myths at the Individual and Community Levels and Modern Contraceptive Use in Urban Africa.

PubMed

Gueye, Abdou; Speizer, Ilene S; Corroon, Meghan; Okigbo, Chinelo C

2015-12-01

Negative myths and misconceptions about family planning are a barrier to modern contraceptive use. Most research on the subject has focused on individual beliefs about contraception; however, given that myths spread easily within communities, it is also important to examine how the prevalence of negative myths in a community affects the aggregate level of method use. Baseline data collected in 2010-2011 by the Measurement, Learning & Evaluation project on women aged 15-49 living in selected cities in Kenya, Nigeria and Senegal were used. Multivariate analyses examined associations between modern contraceptive use and belief in negative myths for individuals and communities. In each country, the family planning myths most prevalent at the individual and community levels were that "people who use contraceptives end up with health problems," "contraceptives are dangerous to women's health" and "contraceptives can harm your womb." On average, women in Nigeria and Kenya believed 2.7 and 4.6 out of eight selected myths, respectively, and women in Senegal believed 2.6 out of seven. Women's individual-level belief in myths was negatively associated with their modern contraceptive use in all three countries (odds ratios, 0.2-0.7). In Nigeria, the women's community-level myth variable was positively associated with modern contraceptive use (1.6), whereas the men's community-level myth variable was negatively associated with use (0.6); neither community-level variable was associated with modern contraceptive use in Kenya or Senegal. Education programs are needed to dispel common myths and misconceptions about modern contraceptives. In Nigeria, programs that encourage community-level discussions may be effective at reducing myths and increasing modern contraceptive use.

Belief in Family Planning Myths at the Individual And Community Levels and Modern Contraceptive Use in Urban Africa

PubMed Central

Gueye, Abdou; Speizer, Ilene S.; Corroon, Meghan; Okigbo, Chinelo C.

2016-01-01

Context Negative myths and misconceptions about family planning are a barrier to modern contraceptive use. Most research on the subject has focused on individual beliefs about contraception; however, given that myths spread easily within communities, it is also important to examine how the prevalence of negative myths in a community affects the aggregate level of method use. Methods Baseline data collected in 2010–2011 by the Measurement, Learning & Evaluation project on women aged 15–49 living in selected cities in Kenya, Nigeria and Senegal were used. Multivariate analyses examined associations between modern contraceptive use and belief in negative myths for individuals and communities. Results In each country, the family planning myths most prevalent at the individual and community levels were that “people who use contraceptives end up with health problems,” “contraceptives are dangerous to women's health” and “contraceptives can harm your womb.” On average, women in Nigeria and Kenya believed 2.7 and 4.6 out of eight selected myths, respectively, and women in Senegal believed 2.6 out of seven. Women's individual-level belief in myths was negatively associated with their modern contraceptive use in all three countries (odds ratios, 0.2–0.7). In Nigeria, the women's community-level myth variable was positively associated with modern contraceptive use (1.6), whereas the men's community-level myth variable was negatively associated with use (0.6); neither community-level variable was associated with modern contraceptive use in Kenya or Senegal. Conclusion Education programs are needed to dispel common myths and misconceptions about modern contraceptives. In Nigeria, programs that encourage community-level discussions may be effective at reducing myths and increasing modern contraceptive use. PMID:26871727

Daily variability in working memory is coupled with negative affect: the role of attention and motivation.

PubMed

Brose, Annette; Schmiedek, Florian; Lövdén, Martin; Lindenberger, Ulman

2012-06-01

Across days, individuals experience varying levels of negative affect, control of attention, and motivation. We investigated whether this intraindividual variability was coupled with daily fluctuations in working memory (WM) performance. In 100 days, 101 younger individuals worked on a spatial N-back task and rated negative affect, control of attention, and motivation. Results showed that individuals differed in how reliably WM performance fluctuated across days, and that subjective experiences were primarily linked to performance accuracy. WM performance was lower on days with higher levels of negative affect, reduced control of attention, and reduced task-related motivation. Thus, variables that were found to predict WM in between-subjects designs showed important relationships to WM at the within-person level. In addition, there was shared predictive variance among predictors of WM. Days with increased negative affect and reduced performance were also days with reduced control of attention and reduced motivation to work on tasks. These findings are in line with proposed mechanisms linking negative affect and cognitive performance.

Toward human resource management in inter-professional health practice: linking organizational culture, group identity and individual autonomy.

PubMed

Tataw, David

2012-01-01

The literature on team and inter-professional care practice describes numerous barriers to the institutionalization of inter-professional healthcare. Responses to slow institutionalization of inter-professional healthcare practice have failed to describe change variables and to identify change agents relevant to inter-professional healthcare practice. The purpose of this paper is to (1) describe individual and organizational level barriers to collaborative practice in healthcare; (2) identify change variables relevant to the institutionalization of inter-professional practice at individual and organizational levels of analysis; and (3) identify human resource professionals as change agents and describe how the strategic use of the human resource function could transform individual and organizational level change variables and therefore facilitate the healthcare system's shift toward inter-professional practice. A proposed program of institutionalization includes the following components: a strategic plan to align human resource functions with organizational level inter-professional healthcare strategies, activities to enhance professional competencies and the organizational position of human resource personnel, activities to integrate inter-professional healthcare practices into the daily routines of institutional and individual providers, activities to stand up health provider champions as permanent leaders of inter-professional teams with human resource professionals as consultants and activities to bring all key players to the table including health providers. Copyright © 2012 John Wiley & Sons, Ltd.

Coordinating the effects of multiple variables: a skill fundamental to scientific thinking.

PubMed

Kuhn, Deanna; Pease, Maria; Wirkala, Clarice

2009-07-01

The skill of predicting outcomes based on simultaneous effects of multiple factors was examined. Over five sessions, 91 sixth graders engaged this task either individually or in pairs and either preceded or followed by six sessions on the more widely studied inquiry task that requires designing and interpreting experiments to identify individual effects. Final assessment, while indicating a high level of mastery on the inquiry task, showed progress but continuing conceptual challenges on the multivariable prediction task having to do with understanding of variables, variable levels, and consistency of a variable's operation across occasions. Task order had a significant but limited effect, and social collaboration conferred only a temporary benefit that disappeared in a final individual assessment. In a follow-up study, the lack of effect of social collaboration was confirmed, as was that of feedback on incorrect answers. Although fundamental to science, the concept that variables operate jointly and, under equivalent conditions, consistently across occasions is one that children appear to acquire only gradually and, therefore, one that cannot be assumed to be in place.

Characterizing individual differences in functional connectivity using dual-regression and seed-based approaches.

PubMed

Smith, David V; Utevsky, Amanda V; Bland, Amy R; Clement, Nathan; Clithero, John A; Harsch, Anne E W; McKell Carter, R; Huettel, Scott A

2014-07-15

A central challenge for neuroscience lies in relating inter-individual variability to the functional properties of specific brain regions. Yet, considerable variability exists in the connectivity patterns between different brain areas, potentially producing reliable group differences. Using sex differences as a motivating example, we examined two separate resting-state datasets comprising a total of 188 human participants. Both datasets were decomposed into resting-state networks (RSNs) using a probabilistic spatial independent component analysis (ICA). We estimated voxel-wise functional connectivity with these networks using a dual-regression analysis, which characterizes the participant-level spatiotemporal dynamics of each network while controlling for (via multiple regression) the influence of other networks and sources of variability. We found that males and females exhibit distinct patterns of connectivity with multiple RSNs, including both visual and auditory networks and the right frontal-parietal network. These results replicated across both datasets and were not explained by differences in head motion, data quality, brain volume, cortisol levels, or testosterone levels. Importantly, we also demonstrate that dual-regression functional connectivity is better at detecting inter-individual variability than traditional seed-based functional connectivity approaches. Our findings characterize robust-yet frequently ignored-neural differences between males and females, pointing to the necessity of controlling for sex in neuroscience studies of individual differences. Moreover, our results highlight the importance of employing network-based models to study variability in functional connectivity. Copyright © 2014 Elsevier Inc. All rights reserved.

Variability of annoyance response due to aircraft noise

NASA Technical Reports Server (NTRS)

Dempsey, T. K.; Cawthorn, J. M.

1979-01-01

An investigation was conducted to study the variability in the response of subjects participating in noise experiments. This paper presents a description of a model developed to include this variability which incorporates an aircraft-noise adaptation level or an annoyance calibration for each individual. The results indicate that the use of an aircraft-noise adaption level improved prediction accuracy of annoyance responses (and simultaneously reduced response variation).

How landscape dynamics link individual- to population-level movement patterns: A multispecies comparison of ungulate relocation data

USGS Publications Warehouse

Mueller, Thomas; Olson, K.A.; Dressler, G.; Leimgruber, Peter; Fuller, Todd K.; Nicholson, Craig; Novaro, A.J.; Bolgeri, M.J.; Wattles, David W.; DeStefano, Stephen; Calabrese, J.M.; Fagan, William F.

2011-01-01

Aim  To demonstrate how the interrelations of individual movements form large-scale population-level movement patterns and how these patterns are associated with the underlying landscape dynamics by comparing ungulate movements across species.Locations  Arctic tundra in Alaska and Canada, temperate forests in Massachusetts, Patagonian Steppes in Argentina, Eastern Steppes in Mongolia.Methods  We used relocation data from four ungulate species (barren-ground caribou, Mongolian gazelle, guanaco and moose) to examine individual movements and the interrelation of movements among individuals. We applied and developed a suite of spatial metrics that measure variation in movement among individuals as population dispersion, movement coordination and realized mobility. Taken together, these metrics allowed us to quantify and distinguish among different large-scale population-level movement patterns such as migration, range residency and nomadism. We then related the population-level movement patterns to the underlying landscape vegetation dynamics via long-term remote sensing measurements of the temporal variability, spatial variability and unpredictability of vegetation productivity.Results  Moose, which remained in sedentary home ranges, and guanacos, which were partially migratory, exhibited relatively short annual movements associated with landscapes having very little broad-scale variability in vegetation. Caribou and gazelle performed extreme long-distance movements that were associated with broad-scale variability in vegetation productivity during the peak of the growing season. Caribou exhibited regular seasonal migration in which individuals were clustered for most of the year and exhibited coordinated movements. In contrast, gazelle were nomadic, as individuals were independently distributed and moved in an uncoordinated manner that relates to the comparatively unpredictable (yet broad-scale) vegetation dynamics of their landscape.Main conclusions  We show how broad-scale landscape unpredictability may lead to nomadism, an understudied type of long-distance movement. In contrast to classical migration where landscapes may vary at broad scales but in a predictable manner, long-distance movements of nomadic individuals are uncoordinated and independent from other such individuals. Landscapes with little broad-scale variability in vegetation productivity feature smaller-scale movements and allow for range residency. Nomadism requires distinct integrative conservation strategies that facilitate long-distance movements across the entire landscape and are not limited to certain migration corridors.

How landscape dynamics link individual- to population-level movement patterns: A multispecies comparison of ungulate relocation data

USGS Publications Warehouse

Mueller, T.; Olson, K.A.; Dressler, G.; Leimgruber, P.; Fuller, T.K.; Nicolson, C.; Novaro, A.J.; Bolgeri, M.J.; Wattles, David W.; DeStefano, S.; Calabrese, J.M.; Fagan, W.F.

2011-01-01

Aim To demonstrate how the interrelations of individual movements form large-scale population-level movement patterns and how these patterns are associated with the underlying landscape dynamics by comparing ungulate movements across species. Locations Arctic tundra in Alaska and Canada, temperate forests in Massachusetts, Patagonian Steppes in Argentina, Eastern Steppes in Mongolia. Methods We used relocation data from four ungulate species (barren-ground caribou, Mongolian gazelle, guanaco and moose) to examine individual movements and the interrelation of movements among individuals. We applied and developed a suite of spatial metrics that measure variation in movement among individuals as population dispersion, movement coordination and realized mobility. Taken together, these metrics allowed us to quantify and distinguish among different large-scale population-level movement patterns such as migration, range residency and nomadism. We then related the population-level movement patterns to the underlying landscape vegetation dynamics via long-term remote sensing measurements of the temporal variability, spatial variability and unpredictability of vegetation productivity. Results Moose, which remained in sedentary home ranges, and guanacos, which were partially migratory, exhibited relatively short annual movements associated with landscapes having very little broad-scale variability in vegetation. Caribou and gazelle performed extreme long-distance movements that were associated with broad-scale variability in vegetation productivity during the peak of the growing season. Caribou exhibited regular seasonal migration in which individuals were clustered for most of the year and exhibited coordinated movements. In contrast, gazelle were nomadic, as individuals were independently distributed and moved in an uncoordinated manner that relates to the comparatively unpredictable (yet broad-scale) vegetation dynamics of their landscape. Main conclusions We show how broad-scale landscape unpredictability may lead to nomadism, an understudied type of long-distance movement. In contrast to classical migration where landscapes may vary at broad scales but in a predictable manner, long-distance movements of nomadic individuals are uncoordinated and independent from other such individuals. Landscapes with little broad-scale variability in vegetation productivity feature smaller-scale movements and allow for range residency. Nomadism requires distinct integrative conservation strategies that facilitate long-distance movements across the entire landscape and are not limited to certain migration corridors. ?? 2011 Blackwell Publishing Ltd.

The Predictive Role of Values and Perceived Social Support Variables in Marital Adjustment

ERIC Educational Resources Information Center

Mert, Abdullah

2018-01-01

The aim of this study was to examine the predictive role of values and perceived social support variables in marital adjustment level among married individuals. A total of 422 (211 pairs) married individuals who agreed to participate voluntarily were included. The study was conducted in accordance with the relational screening model. "Dyadic…

Individual and contextual factors related to dental caries in underprivileged Brazilian adolescents.

PubMed

Vazquez, Fabiana de Lima; Cortellazzi, Karine Laura; Kaieda, Armando Koichiro; Bulgareli, Jaqueline Vilela; Mialhe, Fabio Luiz; Ambrosano, Glaucia Maria Bovi; da Silva Tagliaferro, Elaine Pereira; Guerra, Luciane Miranda; de Castro Meneghim, Marcelo; Pereira, Antonio Carlos

2015-01-20

Investigate the individual and contextual variables related to caries in underprivileged adolescents, and the disparity in distribution of the disease. Cross-sectional analytical study, conducted in the city of Piracicaba, SP, Brazil, in 2012. The probabilistic sample was composed of 1,179 adolescents from 15-19 years of age, randomly selected from 21 state schools and 34 Primary Health Units--Family Health (PHU-FH). The dependent variables studied were number of decayed teeth and caries experience (DMFT). The independent variables were classified into individual (clinical, sociodemographic, psychosocial, self-perception, impact on oral health, access to services, and quality of life) and contextual (social exclusion index, total number of residents in suburb, literacy rate, and the following variables given in percentages: residences in the home ownership category, provision of domestic sewerage, trash collection, families with income of over 1 minimum wage per month, and families without monthly income) variables. The multilevel regression model was estimated by the PROC GLIMMIX (Generalized Linear Models-Mixed) procedure, considering the individual variables as Level 1 and the contextual variables of the suburbs as Level 2. Adjustment of the model was evaluated by -2 Res Log Likelihood with α = 0.05. As regards the individual variables, adolescents who declared having a prison inmate in the Family and resided in homes with a larger number of persons, showed a higher number of decayed teeth. There were a larger number of decayed teeth, a higher DMFT value, and worse self-perception as regards the health of their teeth and mouth. Other variables, such as being of the female gender, age and time since last visit to the dentist were related to the DMFT index. As regards the contextual variables, the DMFT was lower in suburbs with greater access to domestic sewage, and the number of decayed teeth was higher in suburbs with the worst social exclusion indices. Individual and contextual variables were associated with the presence of caries and DMFT index in underprivileged adolescents, indicating that they must be taken into consideration in the formulation of policies directed towards oral health promotion and prevention activities in this group.

Temperament as a Predictor of Symptomotology and Adaptive Functioning in Adolescents with High-Functioning Autism

PubMed Central

Schwartz, Caley B.; Henderson, Heather A.; Inge, Anne P.; Zahka, Nicole E.; Coman, Drew C.; Kojkowski, Nicole M.; Hileman, Camilla M.; Mundy, Peter C.

2009-01-01

Variation in temperament is characteristic of all people but is rarely studied as a predictor of individual differences among individuals with autism. Relative to a matched comparison sample, adolescents with High-Functioning Autism (HFA) reported lower levels of Surgency and higher levels of Negative Affect. Variability in temperament predicted symptomotology, social skills, and social-emotional outcomes differently for individuals with HFA than for the comparison sample. This study is unique in that temperament was measured by self-report, while all outcome measures were reported by parents. The broader implications of this study suggest that by identifying individual variability in constructs, such as temperament, that may influence adaptive functioning, interventions may be developed to target these constructs and increase the likelihood that individuals with HFA will achieve more adaptive life outcomes. PMID:19165586

Social Capital and Suicidal Ideation in Community-Dwelling Older Residents: A Multilevel Analysis of 10,094 Subjects in Japan.

PubMed

Noguchi, Masayuki; Kobayashi, Tomoko; Iwase, Toshihide; Suzuki, Etsuji; Kawachi, Ichiro; Takao, Soshi

2017-01-01

Social capital, the collective resources of groups including perceptions of trust and reciprocity, is recognized as an important contributor to suicide. We examined the association of individual- and community-level social capital with suicidal ideation after adjusting for social support among older adults living in the community. In August 2010 we sent questionnaires to all residents aged 65 years and older living in 3 rural municipalities (N = 21,232) in Okayama Prefecture, Japan; 13,919 questionnaires were returned (response rate: 65.6%). The final analysis included 10,094 participants. The outcome variable was suicidal ideation. Exposure variables were individual-level mistrust and lack of reciprocity (level 1), and the aggregated responses of these variables from 35 communities in the municipalities (level 2). Covariates included age, sex, educational attainment, marital status, the number of cohabitants, years of residence, self-rated socioeconomic status, disability, social support, and psychological distress. Multilevel logistic regression analysis was performed to obtain odds ratios (ORs) and 95% confidence intervals (CIs). After adjusting for social support and psychological distress, we found that mistrust and lack of reciprocity were only associated with suicidal ideation at the individual level. Stratified analysis showed that among subjects with psychological distress, mistrust was associated with suicidal ideation at individual (OR: 1.88; 95% CI: 1.42-2.51) and community levels (OR: 1.98; 95% CI: 1.02-3.81). Our findings show that individual- and community-level social capital is a possible protective factor for suicidal ideation, particularly for people with psychological distress. Copyright © 2017 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

The importance of individual variation in the dynamics of animal collective movements.

PubMed

Del Mar Delgado, Maria; Miranda, Maria; Alvarez, Silvia J; Gurarie, Eliezer; Fagan, William F; Penteriani, Vincenzo; di Virgilio, Agustina; Morales, Juan Manuel

2018-05-19

Animal collective movements are a key example of a system that links two clearly defined levels of organization: the individual and the group. Most models investigating collective movements have generated coherent collective behaviours without the inclusion of individual variability. However, new individual-based models, together with emerging empirical information, emphasize that within-group heterogeneity may strongly influence collective movement behaviour. Here we (i) review the empirical evidence for individual variation in animal collective movements, (ii) explore how theoretical investigations have represented individual heterogeneity when modelling collective movements and (iii) present a model to show how within-group heterogeneity influences the collective properties of a group. Our review underscores the need to consider variability at the level of the individual to improve our understanding of how individual decision rules lead to emergent movement patterns, and also to yield better quantitative predictions of collective behaviour.This article is part of the theme issue 'Collective movement ecology'. © 2018 The Author(s).

Sodium and potassium urinary excretion levels of preschool children: Individual, daily, and seasonal differences.

PubMed

Yasutake, Kenichiro; Nagafuchi, Mikako; Izu, Ryoji; Kajiyama, Tomomi; Imai, Katsumi; Murata, Yusuke; Ohe, Kenji; Enjoji, Munechika; Tsuchihashi, Takuya

2017-06-01

In this study, the authors measured sodium and potassium concentrations in spot urine samples of preschool children on multiple days, and evaluated individual, daily, and seasonal effects. A total of 104 healthy preschool children aged 4 to 5 years were studied. Urine samples were collected from the first urine of the day after waking for three consecutive days (Monday-Wednesday) four times a year (spring, summer, autumn, winter). The authors estimated the daily urine volume as 500 mL and daily creatinine excretion as 300 mg, and used these to calculate daily sodium and potassium excretion levels. Daily sodium and potassium excretion levels and sodium to potassium ratios were highly variable. The coefficient variant in the children's excretion levels were also high within and between individuals. Sodium excretion levels and sodium to potassium ratios were higher on Monday (weekend sodium intakes) than Tuesday. Season had no effect on sodium or potassium excretion levels, but the sodium to potassium ratio was higher in summer than in winter. In conclusion, levels of urinary sodium excretion are comparatively high and those of potassium are low in preschool students, with high variability within and between individuals. ©2017 Wiley Periodicals, Inc.

Regional and social differences concerning overweight, participation in health check-ups and vaccination. Analysis of data from a whole birth cohort of 6-year old children in a prosperous German city

PubMed Central

Koller, Daniela; Mielck, Andreas

2009-01-01

Background Studies on health inequalities still focus mostly on adults. Research about social disparities and health in children is slowly increasing, also in Germany, but these studies are mostly restricted to individual social variables derived from the parents to determine social class. This paper analyses the data of the medical check-up prior to school enrolment to determine differences concerning overweight, participation in health check-ups and immunization; it includes individual social variables but also regional variables describing the social environment of the children. Methods The dataset includes 9,353 children who started school in 2004 in Munich, Germany. Three dependent variables are included (i.e. overweight, health check-ups, vaccinations). The individual level social variables are: children's sex, mother tongue of the parents, Kindergarten visit. On the small scale school district level, two regional social variables could be included as well, i.e. percentage of single-parent households, percentage of households with low educational level. Associations are assessed by cross tables and regression analyses. The regional level variables are included by multilevel analyses. Results The analyses indicate that there is a large variation between the school districts concerning the three dependent variables, and that there is no district with very 'problematic values' for all three of them (i.e. high percentage of overweight, low levels of health check-ups and vaccinations). Throughout the bivariate and multivariate analyses, the mother tongue of the children's parents shows the most pronounced association with these dependent variables; i.e. children growing up in non-German-speaking families tend to be more overweight and don't visit preventive check-ups as often as children of German-speaking parents. An opposite association can be seen concerning vaccinations. Regional level influences are present as well, but they are rather small when the individual level social variables are controlled for. Conclusion The dataset of the medical check-up prior to school enrolment offers a great opportunity for public health research, as it comprises a whole age cohort. The number and scope of variables is quite limited, though. On one hand, it includes only few variables on health or health related risks. On the other, it would be important to have more information from the region where the children live, e.g. the availability of community and health care services for parents and children, social networks of families with children, areas where children can play outside, traffic noise and air pollution. Despite these shortcomings, the need for specific interventions can already be derived from the data analyzed here, e.g. programs to reduce overweight in children should focus on parents with a mother tongue other than German. PMID:19183444

The effects of individual- and network-level factors on discussion of cancer experiences: Survivors of childhood cancer in Korea.

PubMed

Kim, Min Ah; Yi, Jaehee; Prince, Kort C; Nagelhout, Elizabeth; Wu, Yelena P

2018-01-01

This study aimed to identify young adult Korean cancer survivors' individual- (psychological distress, stigma, sociodemographic variables, and cancer-related variables) and network-level factors (relationship type, social support type) that influence discussion of their cancer experiences. Sixty-eight survivors of childhood cancer who were recruited using snowball sampling nominated 245 individuals from their networks, including family and intimate partners (40%) and friends and acquaintances (60%), as people with whom they most frequently interacted. Results of multilevel modeling analysis indicated that higher levels of internalized shame were a prominent individual-level factor associated with a lack of discussion of cancer experiences. Relationship type and support type at the network-level were also significant correlates of discussion of cancer experiences. Programs for reducing the survivors' shame, improving illness identity, and providing professional training for building social relationships that are intimate and in which they could exchange reciprocal support may help Korean childhood cancer survivors to openly share their cancer experiences with others in their social network and to be successful in the journey of cancer survivorship.

The influence of community and individual health literacy on self-reported health status.

PubMed

Sentell, Tetine; Zhang, Wei; Davis, James; Baker, Kathleen Kromer; Braun, Kathryn L

2014-02-01

Individual health literacy is an established predictor of individual health outcomes. Community-level health literacy may also impact individual health, yet limited research has simultaneously considered the influence of individual and community health literacy on individual health. The study goal was to determine if community health literacy had an independent relationship with individual self-reported health beyond individual health literacy. We used data from the 2008 and 2010 Hawai'i Health Survey, a representative statewide telephone survey. Multilevel models predicted individual self-reported health by both individual and community health literacy, controlling for relevant individual-level (education, race/ethnicity, gender, poverty, insurance status, age, and marital status) and community-level variables (community poverty and community education). The sample included 11,779 individuals within 37 communities. Individual health literacy was defined by validated self-reported measurement. Communities were defined by zip code combinations. Community health literacy was defined as the percentage of individuals within a community reporting low health literacy. Census data by ZIP Code Tabulation Areas provided community-level variables. In descriptive results, 18.2 % self-reported low health literacy, and 14.7 % reported self-reported poor health. Community-level low health literacy ranged from 5.37 % to 35.99 %. In final, multilevel models, both individual (OR: 2.00; 95 % CI: 1.63-2.44) and community low health literacy (OR: 1.02; 95 % CI: 1.00-1.03) were significantly positively associated with self-reported poor health status. Each percentage increase of average low health literacy within a community was associated with an approximately 2 % increase in poor self-reported health for individuals in that community. Also associated with poorer health were lower educational attainment, older age, poverty, and non-White race. Both individual and community health literacy are significant, distinct correlates of individual general health status. Primary care providers and facilities should consider and address health literacy at both community and individual levels.

Data-Driven User Feedback: An Improved Neurofeedback Strategy considering the Interindividual Variability of EEG Features.

PubMed

Han, Chang-Hee; Lim, Jeong-Hwan; Lee, Jun-Hak; Kim, Kangsan; Im, Chang-Hwan

2016-01-01

It has frequently been reported that some users of conventional neurofeedback systems can experience only a small portion of the total feedback range due to the large interindividual variability of EEG features. In this study, we proposed a data-driven neurofeedback strategy considering the individual variability of electroencephalography (EEG) features to permit users of the neurofeedback system to experience a wider range of auditory or visual feedback without a customization process. The main idea of the proposed strategy is to adjust the ranges of each feedback level using the density in the offline EEG database acquired from a group of individuals. Twenty-two healthy subjects participated in offline experiments to construct an EEG database, and five subjects participated in online experiments to validate the performance of the proposed data-driven user feedback strategy. Using the optimized bin sizes, the number of feedback levels that each individual experienced was significantly increased to 139% and 144% of the original results with uniform bin sizes in the offline and online experiments, respectively. Our results demonstrated that the use of our data-driven neurofeedback strategy could effectively increase the overall range of feedback levels that each individual experienced during neurofeedback training.

Data-Driven User Feedback: An Improved Neurofeedback Strategy considering the Interindividual Variability of EEG Features

PubMed Central

Lim, Jeong-Hwan; Lee, Jun-Hak; Kim, Kangsan

2016-01-01

It has frequently been reported that some users of conventional neurofeedback systems can experience only a small portion of the total feedback range due to the large interindividual variability of EEG features. In this study, we proposed a data-driven neurofeedback strategy considering the individual variability of electroencephalography (EEG) features to permit users of the neurofeedback system to experience a wider range of auditory or visual feedback without a customization process. The main idea of the proposed strategy is to adjust the ranges of each feedback level using the density in the offline EEG database acquired from a group of individuals. Twenty-two healthy subjects participated in offline experiments to construct an EEG database, and five subjects participated in online experiments to validate the performance of the proposed data-driven user feedback strategy. Using the optimized bin sizes, the number of feedback levels that each individual experienced was significantly increased to 139% and 144% of the original results with uniform bin sizes in the offline and online experiments, respectively. Our results demonstrated that the use of our data-driven neurofeedback strategy could effectively increase the overall range of feedback levels that each individual experienced during neurofeedback training. PMID:27631005

Social Cognitive Correlates of Physical Activity in Black Individuals With Multiple Sclerosis.

PubMed

Kinnett-Hopkins, Dominique; Motl, Robert W

2016-04-01

To examine variables from social cognitive theory as correlates of physical activity in black and white individuals with multiple sclerosis (MS). Cross-sectional. National survey. Black (n=151) and white (n=185) individuals with MS were recruited through the North American Research Committee on Multiple Sclerosis Registry. Not applicable. The battery of questionnaires included information on demographic and clinical characteristics, physical activity, exercise self-efficacy, function, social support, exercise outcome expectations, and exercise goal setting and planning. Black individuals with MS reported significantly lower levels of physical activity compared with white individuals with MS. Physical activity levels were significantly correlated with self-efficacy, outcome expectations, functional limitations as impediments, and goal setting in black participants with MS. The pattern and magnitude of correlations were comparable with those observed in white participants based on Fisher z tests. Researchers should consider applying behavioral interventions that target social cognitive theory variables for increasing physical activity levels among black individuals with MS. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Predictors for Physical Activity in Adolescent Girls Using Statistical Shrinkage Techniques for Hierarchical Longitudinal Mixed Effects Models

PubMed Central

Grant, Edward M.; Young, Deborah Rohm; Wu, Tong Tong

2015-01-01

We examined associations among longitudinal, multilevel variables and girls’ physical activity to determine the important predictors for physical activity change at different adolescent ages. The Trial of Activity for Adolescent Girls 2 study (Maryland) contributed participants from 8th (2009) to 11th grade (2011) (n=561). Questionnaires were used to obtain demographic, and psychosocial information (individual- and social-level variables); height, weight, and triceps skinfold to assess body composition; interviews and surveys for school-level data; and self-report for neighborhood-level variables. Moderate to vigorous physical activity minutes were assessed from accelerometers. A doubly regularized linear mixed effects model was used for the longitudinal multilevel data to identify the most important covariates for physical activity. Three fixed effects at the individual level and one random effect at the school level were chosen from an initial total of 66 variables, consisting of 47 fixed effects and 19 random effects variables, in additional to the time effect. Self-management strategies, perceived barriers, and social support from friends were the three selected fixed effects, and whether intramural or interscholastic programs were offered in middle school was the selected random effect. Psychosocial factors and friend support, plus a school’s physical activity environment, affect adolescent girl’s moderate to vigorous physical activity longitudinally. PMID:25928064

Precision of information, sensational information, and self-efficacy information as message-level variables affecting risk perceptions.

PubMed

Dahlstrom, Michael F; Dudo, Anthony; Brossard, Dominique

2012-01-01

Studies that investigate how the mass media cover risk issues often assume that certain characteristics of content are related to specific risk perceptions and behavioral intentions. However, these relationships have seldom been empirically assessed. This study tests the influence of three message-level media variables--risk precision information, sensational information, and self-efficacy information--on perceptions of risk, individual worry, and behavioral intentions toward a pervasive health risk. Results suggest that more precise risk information leads to increased risk perceptions and that the effect of sensational information is moderated by risk precision information. Greater self-efficacy information is associated with greater intention to change behavior, but none of the variables influence individual worry. The results provide a quantitative understanding of how specific characteristics of informational media content can influence individuals' responses to health threats of a global and uncertain nature. © 2011 Society for Risk Analysis.

The role of supervisor emotional support on individual job satisfaction: A multilevel analysis.

PubMed

Pohl, Sabine; Galletta, Maura

2017-02-01

Supervisor emotional support is a strong determinant of job satisfaction. There is no study examining the effect of supervisor emotional support at the group level on job satisfaction. Multilevel statistical techniques can help disentangle the effects of subjective assessments from those of group factors. The study's aim was to examine the moderating role of supervisor emotional support (group-level variable) on the relationship between work engagement and job satisfaction (individual-level variables). A cross-sectional study was performed in 39units from three Belgian hospitals. A total of 323 nurses completed a self-reported questionnaire. We carried out a multilevel analysis by using Hierarchical Linear Modeling. The results showed that the cross-level interaction was significant. Hence, at individual-level, the nurses with high levels of work engagement showed high levels of job satisfaction and this relationship was stronger when supervisor emotional support at group-level was high. Contextual differences among groups had an impact on the form of the work engagement-job satisfaction relationship. This relationship between work engagement and job satisfaction is an individual and group level phenomenon. Ways to enhance emotional supervisor support include training supervisors in providing support and enhancing communication between nurses and supervisors. Copyright © 2016 Elsevier Inc. All rights reserved.

Social capital and health-purely a question of context?

PubMed

Giordano, Giuseppe Nicola; Ohlsson, Henrik; Lindström, Martin

2011-07-01

Debate still surrounds which level of analysis (individual vs. contextual) is most appropriate to investigate the effects of social capital on health. Applying multilevel ecometric analyses to British Household Panel Survey data, we estimated fixed and random effects between five individual-, household- and small area-level social capital indicators and general health. We further compared the variance in health attributable to each level using intraclass correlations. Our results demonstrate that association between social capital and health depends on indicator type and level investigated, with one quarter of total individual-level health variance found at the household level. However, individual-level social capital variables and other health determinants appear to influence contextual-level variance the most. Copyright © 2011 Elsevier Ltd. All rights reserved.

Evidence from Individual Inference for High-Dimensional Coexistence: Long-Term Experiments on Recruitment Response

PubMed Central

Clark, James S.; Soltoff, Benjamin D.; Powell, Amanda S.; Read, Quentin D.

2012-01-01

Background For competing species to coexist, individuals must compete more with others of the same species than with those of other species. Ecologists search for tradeoffs in how species might partition the environment. The negative correlations among competing species that would be indicative of tradeoffs are rarely observed. A recent analysis showed that evidence for partitioning the environment is available when responses are disaggregated to the individual scale, in terms of the covariance structure of responses to environmental variation. That study did not relate that variation to the variables to which individuals were responding. To understand how this pattern of variation is related to niche variables, we analyzed responses to canopy gaps, long viewed as a key variable responsible for species coexistence. Methodology/Principal Findings A longitudinal intervention analysis of individual responses to experimental canopy gaps with 12 yr of pre-treatment and 8 yr post-treatment responses showed that species-level responses are positively correlated – species that grow fast on average in the understory also grow fast on average in response to gap formation. In other words, there is no tradeoff. However, the joint distribution of individual responses to understory and gap showed a negative correlation – species having individuals that respond most to gaps when previously growing slowly also have individuals that respond least to gaps when previously growing rapidly (e.g., Morus rubra), and vice versa (e.g., Quercus prinus). Conclusions/Significance Because competition occurs at the individual scale, not the species scale, aggregated species-level parameters and correlations hide the species-level differences needed for coexistence. By disaggregating models to the scale at which the interaction occurs we show that individual variation provides insight for species differences. PMID:22393349

A Socioecological Predication Model of Posttraumatic Stress Disorder in Low-Income, High-Risk Prenatal Native Hawaiian/Pacific Islander Women.

PubMed

Dodgson, Joan E; Oneha, Mary Frances; Choi, Myunghan

2014-01-01

Only recently has perinatal posttraumatic stress disorder (PTSD) been researched in any depth; however, the causes and consequences of this serious illness remain unclear. Most commonly, childbirth trauma and interpersonal violence have been reported as contributing factors. However, not all Native Hawaiian/Pacific Islander (NHPI) women who experience these events experience PTSD. The factors affecting PTSD are many and complex, intertwining individual, family, and community contexts. Using a socioecological framework, 3 levels of contextual variables were incorporated in this study (individual, family, and social/community). The purpose of this study was to determine the socioecological predictors associated with prenatal PTSD among NHPI. A case-control design was used to collect retrospective data about socioecological variables from medical record data. The sample was low-income, high-risk NHPI women receiving perinatal health care at a rural community health center in Hawaii who screened positive (n = 55) or negative (n = 91) for PTSD. Hierarchical logistic regression was conducted to determine socioecological predictors of positive PTSD screening. Although the majority of women (66.4%) experienced some form of interpersonal violence, a constellation of significant predictor variables from all 3 levels of the model were identified: depression (individual level), lack of family support and family stress (family level), and violence (social/community level). Each of the predictor variables has been identified by other researchers as significantly affecting perinatal PTSD. However, it is because these variables occur together that a more complex picture emerges, suggesting the importance of considering multiple variables in context when identifying and caring for these women. Although additional research is needed, it is possible that the significant predictor variables could be useful in identifying women who are at higher risk for PTSD in other similar populations. © 2014 by the American College of Nurse‐Midwives.

School Structural Characteristics, Student Effort, Peer Associations, and Parental Involvement: The Influence of School- and Individual-Level Factors on Academic Achievement

ERIC Educational Resources Information Center

Stewart, Endya B.

2008-01-01

This research examines the extent to which individual-level and school structural variables are predictors of academic achievement among a sample of 10th grade students abstracted from the National Educational Longitudinal Study database. A secondary analysis of the data produced the following findings. The study results show that individual-level…

Contextual and individual factors associated with dental services utilisation by Brazilian adults: A multilevel analysis

PubMed Central

2018-01-01

Background Inequalities in the utilisation of dental services in Brazil are remarkable. The aim of this study was to evaluate the association of contextual and individual factors with the utilisation of dental services by Brazilian adults using the Andersen’s behavioural model. Methods Individual-level data from 27,017 adults residents in the State capitals who were interviewed in the 2013 Brazilian National Health Survey were pooled with contextual city-level data. The outcomes were non-utilisation of dental services and last dental visit over 12 months ago. Individual predisposing variables were age, sex, race/skin colour, schooling and social network. Individual enabling variables included income, health insurance and registration in primary health care. Individual need variables were self-perceived dental health and self-reported missing teeth. Multilevel logistic regression models were performed to estimate odds ratio (OR) and 95% confidence intervals (95% CIs) of the association of contextual and individual predisposing, enabling and need-related variables with dental services outcomes. Results Predisposing (OR = 0.89; 95% CI 0.81–0.97) and enabling (OR = 0.90; 95% CI 0.85–0.96) contextual factors were associated with non-utilisation of dental services. Individual predisposing (sex, race/skin colour, schooling), enabling (income, health insurance) and need (self-perceived oral health, missing teeth) were associated with non-utilisation of dental services and last dental visit over 12 months ago. The latter was also associated with other individual predisposing (age, social network) and need (eating difficulties due to oral problems) characteristics. Conclusions Individual and contextual determinants influenced dental services utilisation in Brazilian adults. These factors should be on the policy agenda and considered in the organisation of health services aiming to reduce oral health inequalities related to access and utilisation of dental services. PMID:29420660

Contextual and individual factors associated with dental services utilisation by Brazilian adults: A multilevel analysis.

PubMed

Herkrath, Fernando José; Vettore, Mario Vianna; Werneck, Guilherme Loureiro

2018-01-01

Inequalities in the utilisation of dental services in Brazil are remarkable. The aim of this study was to evaluate the association of contextual and individual factors with the utilisation of dental services by Brazilian adults using the Andersen's behavioural model. Individual-level data from 27,017 adults residents in the State capitals who were interviewed in the 2013 Brazilian National Health Survey were pooled with contextual city-level data. The outcomes were non-utilisation of dental services and last dental visit over 12 months ago. Individual predisposing variables were age, sex, race/skin colour, schooling and social network. Individual enabling variables included income, health insurance and registration in primary health care. Individual need variables were self-perceived dental health and self-reported missing teeth. Multilevel logistic regression models were performed to estimate odds ratio (OR) and 95% confidence intervals (95% CIs) of the association of contextual and individual predisposing, enabling and need-related variables with dental services outcomes. Predisposing (OR = 0.89; 95% CI 0.81-0.97) and enabling (OR = 0.90; 95% CI 0.85-0.96) contextual factors were associated with non-utilisation of dental services. Individual predisposing (sex, race/skin colour, schooling), enabling (income, health insurance) and need (self-perceived oral health, missing teeth) were associated with non-utilisation of dental services and last dental visit over 12 months ago. The latter was also associated with other individual predisposing (age, social network) and need (eating difficulties due to oral problems) characteristics. Individual and contextual determinants influenced dental services utilisation in Brazilian adults. These factors should be on the policy agenda and considered in the organisation of health services aiming to reduce oral health inequalities related to access and utilisation of dental services.

Multi-level analysis in information systems research: the case of enterprise resource planning system usage in China

NASA Astrophysics Data System (ADS)

Sun, Yuan; Bhattacherjee, Anol

2011-11-01

Information technology (IT) usage within organisations is a multi-level phenomenon that is influenced by individual-level and organisational-level variables. Yet, current theories, such as the unified theory of acceptance and use of technology, describe IT usage as solely an individual-level phenomenon. This article postulates a model of organisational IT usage that integrates salient organisational-level variables such as user training, top management support and technical support within an individual-level model to postulate a multi-level model of IT usage. The multi-level model was then empirically validated using multi-level data collected from 128 end users and 26 managers in 26 firms in China regarding their use of enterprise resource planning systems and analysed using the multi-level structural equation modelling (MSEM) technique. We demonstrate the utility of MSEM analysis of multi-level data relative to the more common structural equation modelling analysis of single-level data and show how single-level data can be aggregated to approximate multi-level analysis when multi-level data collection is not possible. We hope that this article will motivate future scholars to employ multi-level data and multi-level analysis for understanding organisational phenomena that are truly multi-level in nature.

Effects of a common transcranial direct current stimulation (tDCS) protocol on motor evoked potentials found to be highly variable within individuals over 9 testing sessions.

PubMed

Horvath, Jared Cooney; Vogrin, Simon J; Carter, Olivia; Cook, Mark J; Forte, Jason D

2016-09-01

Transcranial direct current stimulation (tDCS) uses a weak electric current to modulate neuronal activity. A neurophysiologic outcome measure to demonstrate reliable tDCS modulation at the group level is transcranial magnetic stimulation engendered motor evoked potentials (MEPs). Here, we conduct a study testing the reliability of individual MEP response patterns following a common tDCS protocol. Fourteen participants (7m/7f) each underwent nine randomized sessions of 1 mA, 10 min tDCS (3 anode; 3 cathode; 3 sham) delivered using an M1/orbito-frontal electrode montage (sessions separated by an average of ~5.5 days). Fifteen MEPs were obtained prior to, immediately following and in 5 min intervals for 30 min following tDCS. TMS was delivered at 130 % resting motor threshold using neuronavigation to ensure consistent coil localization. A number of non-experimental variables were collected during each session. At the individual level, considerable variability was seen among different testing sessions. No participant demonstrated an excitatory response ≥20 % to all three anodal sessions, and no participant demonstrated an inhibitory response ≥20 % to all three cathodal sessions. Intra-class correlation revealed poor anodal and cathodal test-retest reliability [anode: ICC(2,1) = 0.062; cathode: ICC(2,1) = 0.055] and moderate sham test-retest reliability [ICC(2,1) = 0.433]. Results also revealed no significant effect of tDCS at the group level. Using this common protocol, we found the effects of tDCS on MEP amplitudes to be highly variable at the individual level. In addition, no significant effects of tDCS on MEP amplitude were found at the group level. Future studies should consider utilizing a more strict experimental protocol to potentially account for intra-individual response variations.

Case-Crossover Analysis of Air Pollution Health Effects: A Systematic Review of Methodology and Application

PubMed Central

Carracedo-Martínez, Eduardo; Taracido, Margarita; Tobias, Aurelio; Saez, Marc; Figueiras, Adolfo

2010-01-01

Background Case-crossover is one of the most used designs for analyzing the health-related effects of air pollution. Nevertheless, no one has reviewed its application and methodology in this context. Objective We conducted a systematic review of case-crossover (CCO) designs used to study the relationship between air pollution and morbidity and mortality, from the standpoint of methodology and application. Data sources and extraction A search was made of the MEDLINE and EMBASE databases. Reports were classified as methodologic or applied. From the latter, the following information was extracted: author, study location, year, type of population (general or patients), dependent variable(s), independent variable(s), type of CCO design, and whether effect modification was analyzed for variables at the individual level. Data synthesis The review covered 105 reports that fulfilled the inclusion criteria. Of these, 24 addressed methodological aspects, and the remainder involved the design’s application. In the methodological reports, the designs that yielded the best results in simulation were symmetric bidirectional CCO and time-stratified CCO. Furthermore, we observed an increase across time in the use of certain CCO designs, mainly symmetric bidirectional and time-stratified CCO. The dependent variables most frequently analyzed were those relating to hospital morbidity; the pollutants most often studied were those linked to particulate matter. Among the CCO-application reports, 13.6% studied effect modification for variables at the individual level. Conclusions The use of CCO designs has undergone considerable growth; the most widely used designs were those that yielded better results in simulation studies: symmetric bidirectional and time-stratified CCO. However, the advantages of CCO as a method of analysis of variables at the individual level are put to little use. PMID:20356818

The Effect of Neighborhood Context on the Relationship Between Substance Misuse and Weapons Aggression in Urban Adolescents Seeking ED Care

PubMed Central

Goldstick, Jason Elliott; Lipton, Robert I.; Carter, Patrick; Stoddard, Sarah A.; Newton, Manya F.; Reischl, Thomas; Walton, Maureen; Zimmerman, Marc A.; Cunningham, Rebecca M.

2015-01-01

Background Frameworks for studying the ecology of human behavior suggest that multiple levels of the environment influence behavior and that these levels interact. Applied to studies of weapons aggression, this suggests proximal risk factor (e.g., substance use) effects may differ across neighborhoods. Objectives To estimate how the association between weapons aggression and substance use varies as a function of several community-level variables. Methods Individual-level measures (demographics, behavioral measures) were obtained from a survey of youth aged 14–24 years old seeking care at a Level-1 ED in Flint, Michigan. Community-level variables were obtained from public sources. Logistic generalized additive models were used to test whether community-level variables (crime rates, alcohol outlets, demographics) modify the link between individual-level substance use variables and the primary outcome measure: self-reported past 6-month weapon (firearm/knife) related aggression. Results The effect of marijuana misuse on weapons aggression varied significantly as a function of five community-level variables: racial composition, vacant housing rates, female headed household rates, density of package alcohol outlets, and nearby drug crime rates. The effect of high-risk alcohol use did not depend on any of the eight community variables tested. Conclusions The relationship between marijuana misuse and weapons aggression differed across neighborhoods with generally less association in more disadvantaged neighborhoods, while high-risk alcohol use showed a consistently high association with weapons aggression that did not vary across neighborhoods. The results aid in understanding the contributions of alcohol and marijuana use to the etiology of weapon-related aggression among urban youth, but further study in the general population is required. PMID:25607807

The Effect of Neighborhood Context on the Relationship Between Substance Misuse and Weapons Aggression in Urban Adolescents Seeking ED Care.

PubMed

Goldstick, Jason Elliott; Lipton, Robert I; Carter, Patrick; Stoddard, Sarah A; Newton, Manya F; Reischl, Thomas; Walton, Maureen; Zimmerman, Marc A; Cunningham, Rebecca M

2015-04-01

Frameworks for studying the ecology of human behavior suggest that multiple levels of the environment influence behavior and that these levels interact. Applied to studies of weapons aggression, this suggests proximal risk factor (e.g., substance use) effects may differ across neighborhoods. To estimate how the association between weapons aggression and substance use varies as a function of several community-level variables. Individual-level measures (demographics, behavioral measures) were obtained from a survey of youth aged 14-24 years old seeking care at a Level-1 ED in Flint, Michigan. Community-level variables were obtained from public sources. Logistic generalized additive models were used to test whether community-level variables (crime rates, alcohol outlets, demographics) modify the link between individual-level substance use variables and the primary outcome measure: self-reported past 6-month weapon (firearm/knife) related aggression. The effect of marijuana misuse on weapons aggression varied significantly as a function of five community-level variables: racial composition, vacant housing rates, female headed household rates, density of package alcohol outlets, and nearby drug crime rates. The effect of high-risk alcohol use did not depend on any of the eight community variables tested. The relationship between marijuana misuse and weapons aggression differed across neighborhoods with generally less association in more disadvantaged neighborhoods, while high-risk alcohol use showed a consistently high association with weapons aggression that did not vary across neighborhoods. The results aid in understanding the contributions of alcohol and marijuana use to the etiology of weapon-related aggression among urban youth, but further study in the general population is required.

Beyond R 0: Demographic Models for Variability of Lifetime Reproductive Output

PubMed Central

Caswell, Hal

2011-01-01

The net reproductive rate measures the expected lifetime reproductive output of an individual, and plays an important role in demography, ecology, evolution, and epidemiology. Well-established methods exist to calculate it from age- or stage-classified demographic data. As an expectation, provides no information on variability; empirical measurements of lifetime reproduction universally show high levels of variability, and often positive skewness among individuals. This is often interpreted as evidence of heterogeneity, and thus of an opportunity for natural selection. However, variability provides evidence of heterogeneity only if it exceeds the level of variability to be expected in a cohort of identical individuals all experiencing the same vital rates. Such comparisons require a way to calculate the statistics of lifetime reproduction from demographic data. Here, a new approach is presented, using the theory of Markov chains with rewards, obtaining all the moments of the distribution of lifetime reproduction. The approach applies to age- or stage-classified models, to constant, periodic, or stochastic environments, and to any kind of reproductive schedule. As examples, I analyze data from six empirical studies, of a variety of animal and plant taxa (nematodes, polychaetes, humans, and several species of perennial plants). PMID:21738586

Using crown condition variables as indicators of forest health

Treesearch

Stanley J. Zarnoch; William A. Bechtold; K.W. Stolte

2004-01-01

Indicators of forest health used in previous studies have focused on crown variables analyzed individually at the tree level by summarizing over all species. This approach has the virtue of simplicity but does not account for the three-dimensional attributes of a tree crown, the multivariate nature of the crown variables, or variability among species. To alleviate...

Assessing risk of baleen whale hearing loss from seismic surveys: The effect of uncertainty and individual variation.

PubMed

Gedamke, Jason; Gales, Nick; Frydman, Sascha

2011-01-01

The potential for seismic airgun "shots" to cause acoustic trauma in marine mammals is poorly understood. There are just two empirical measurements of temporary threshold shift (TTS) onset levels from airgun-like sounds in odontocetes. Considering these limited data, a model was developed examining the impact of individual variability and uncertainty on risk assessment of baleen whale TTS from seismic surveys. In each of 100 simulations: 10000 "whales" are assigned TTS onset levels accounting for: inter-individual variation; uncertainty over the population's mean; and uncertainty over weighting of odontocete data to obtain baleen whale onset levels. Randomly distributed whales are exposed to one seismic survey passage with cumulative exposure level calculated. In the base scenario, 29% of whales (5th/95th percentiles of 10%/62%) approached to 1-1.2 km range were exposed to levels sufficient for TTS onset. By comparison, no whales are at risk outside 0.6 km when uncertainty and variability are not considered. Potentially "exposure altering" parameters (movement, avoidance, surfacing, and effective quiet) were also simulated. Until more research refines model inputs, the results suggest a reasonable likelihood that whales at a kilometer or more from seismic surveys could potentially be susceptible to TTS and demonstrate that the large impact uncertainty and variability can have on risk assessment.

Predicting patriarchy: using individual and contextual factors to examine patriarchal endorsement in communities.

PubMed

Crittenden, Courtney A; Wright, Emily M

2013-04-01

In much feminist literature, patriarchy has often been studied as a predictive variable for attitudes toward or acts of violence against women. However, rarely has patriarchy been examined as an outcome across studies. The current study works toward filling this gap by examining several individual-and neighborhood-level factors that might influence patriarchy. Specifically, this research seeks to determine if neighborhood-level attributes related to socioeconomic status, family composition, and demographic information affect patriarchal views after individual-level correlates of patriarchy were controlled. Findings suggest that factors at both the individual- and neighborhood levels, particularly familial characteristics and dynamics, do influence the endorsement of patriarchal views.

Help Seeking in Online Collaborative Groupwork: A Multilevel Analysis

ERIC Educational Resources Information Center

Du, Jianxia; Xu, Jianzhong; Fan, Xitao

2015-01-01

This study examined predictive models for students' help seeking in the context of online collaborative groupwork. Results from multilevel analysis revealed that most of the variance in help seeking was at the individual student level, and multiple variables at the individual level were predictive of help-seeking behaviour. Help seeking was…

Small RNA sequencing in cells and exosomes identifies eQTLs and 14q32 as a region of active export

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

Tsang, Emily K.; Abell, Nathan S.; Li, Xin

Exosomes are small extracellular vesicles that carry heterogeneous cargo, including RNA, between cells. Increasing evidence suggests that exosomes are important mediators of intercellular communication and biomarkers of disease. Despite this, the variability of exosomal RNA between individuals has not been well quantified. To assess this variability, we sequenced the small RNA of cells and exosomes from a 17-member family. Across individuals, we show that selective export of miRNAs occurs not only at the level of specific transcripts, but that a cluster of 74 mature miRNAs on chromosome 14q32 is massively exported in exosomes while mostly absent from cells. We alsomore » observe more interindividual variability between exosomal samples than between cellular ones and identify four miRNA expression quantitative trait loci shared between cells and exosomes. Lastly, our findings indicate that genomically colocated miRNAs can be exported together and highlight the variability in exosomal miRNA levels between individuals as relevant for exosome use as diagnostics.« less

Small RNA sequencing in cells and exosomes identifies eQTLs and 14q32 as a region of active export

DOE PAGES

Tsang, Emily K.; Abell, Nathan S.; Li, Xin; ...

2016-10-31

Exosomes are small extracellular vesicles that carry heterogeneous cargo, including RNA, between cells. Increasing evidence suggests that exosomes are important mediators of intercellular communication and biomarkers of disease. Despite this, the variability of exosomal RNA between individuals has not been well quantified. To assess this variability, we sequenced the small RNA of cells and exosomes from a 17-member family. Across individuals, we show that selective export of miRNAs occurs not only at the level of specific transcripts, but that a cluster of 74 mature miRNAs on chromosome 14q32 is massively exported in exosomes while mostly absent from cells. We alsomore » observe more interindividual variability between exosomal samples than between cellular ones and identify four miRNA expression quantitative trait loci shared between cells and exosomes. Lastly, our findings indicate that genomically colocated miRNAs can be exported together and highlight the variability in exosomal miRNA levels between individuals as relevant for exosome use as diagnostics.« less

Individual- and area-level disparities in access to the road network, subway system and a public bicycle share program on the Island of Montreal, Canada.

PubMed

Fuller, Daniel; Gauvin, Lise; Kestens, Yan

2013-02-01

Few studies have examined potential disparities in access to transportation infrastructures, an important determinant of population health. To examine individual- and area-level disparities in access to the road network, public transportation system, and a public bicycle share program in Montreal, Canada. Examining associations between sociodemographic variables and access to the road network, public transportation system, and a public bicycle share program, 6,495 adult respondents (mean age, 48.7 years; 59.0 % female) nested in 33 areas were included in a multilevel analysis. Individuals with lower incomes lived significantly closer to public transportation and the bicycle share program. At the area level, the interaction between low-education and low-income neighborhoods showed that these areas were significantly closer to public transportation and the bicycle share program controlling for individual and urbanicity variables. More deprived areas of the Island of Montreal have better access to transportation infrastructure than less-deprived areas.

Individual factors and perceived community characteristics in relation to mental health and mental well-being.

PubMed

McAneney, Helen; Tully, Mark A; Hunter, Ruth F; Kouvonen, Anne; Veal, Philip; Stevenson, Michael; Kee, Frank

2015-12-12

It has been argued that though correlated with mental health, mental well-being is a distinct entity. Despite the wealth of literature on mental health, less is known about mental well-being. Mental health is something experienced by individuals, whereas mental well-being can be assessed at the population level. Accordingly it is important to differentiate the individual and population level factors (environmental and social) that could be associated with mental health and well-being, and as people living in deprived areas have a higher prevalence of poor mental health, these relationships should be compared across different levels of neighbourhood deprivation. A cross-sectional representative random sample of 1,209 adults from 62 Super Output Areas (SOAs) in Belfast, Northern Ireland (Feb 2010 - Jan 2011) were recruited in the PARC Study. Interview-administered questionnaires recorded data on socio-demographic characteristics, health-related behaviours, individual social capital, self-rated health, mental health (SF-8) and mental well-being (WEMWBS). Multi-variable linear regression analyses, with inclusion of clustering by SOAs, were used to explore the associations between individual and perceived community characteristics and mental health and mental well-being, and to investigate how these associations differed by the level of neighbourhood deprivation. Thirty-eight and 30 % of variability in the measures of mental well-being and mental health, respectively, could be explained by individual factors and the perceived community characteristics. In the total sample and stratified by neighbourhood deprivation, age, marital status and self-rated health were associated with both mental health and well-being, with the 'social connections' and local area satisfaction elements of social capital also emerging as explanatory variables. An increase of +1 in EQ-5D-3 L was associated with +1SD of the population mean in both mental health and well-being. Similarly, a change from 'very dissatisfied' to 'very satisfied' for local area satisfaction would result in +8.75 for mental well-being, but only in the more affluent of areas. Self-rated health was associated with both mental health and mental well-being. Of the individual social capital explanatory variables, 'social connections' was more important for mental well-being. Although similarities in the explanatory variables of mental health and mental well-being exist, socio-ecological interventions designed to improve them may not have equivalent impacts in rich and poor neighbourhoods.

Motivation and diabetes self-management.

PubMed

Shigaki, Cheryl; Kruse, Robin L; Mehr, David; Sheldon, Kennon M; Bin Ge; Moore, Cherith; Lemaster, Joseph

2010-09-01

To examine the relationship between autonomous motivation and diabetes self-care activities among individuals with diabetes. Seventy-seven individuals recruited from outpatient clinic registries (64% female, 77% Caucasian, mean age 63 years) completed measures of diabetes-related self-care (Summary of Diabetes Self-care Activities), motivation (Treatment Self-regulation Questionnaire), health literacy (Rapid Estimate of Adult Literacy in Medicine, Newest Vital Sign), health (SF-36v2), social support (Social Support Survey) and self-efficacy (Perceived Competence Scale). Autonomous motivation was the only variable significantly associated with maintaining diet (p<0.0001) and blood glucose testing (p<0.04) in regression analyses. No significant associations were identified for exercise. The variable of age approached significance (p = 0.06), with older individuals being less likely to have exercised in the past week. Individuals in this study had difficulty in maintaining self-care demands, especially exercise. Meeting recommended levels of self-care activity was challenging, even for patients with adequate levels of health literacy. Individuals with higher levels of autonomous motivation reported higher frequencies for maintaining diet and testing blood glucose, however, which supports the utility of Self-Determination Theory in promoting diabetes self-care.

[Association between stress and depression levels and treatment adherence among HIV-positive individuals in Hermosillo, México].

PubMed

Piña López, Julio Alfonso; Dávila Tapia, Mariana; Sánchez-Sosa, Juan José; Togawa, Carlos; Cázares Robles, Oscar

2008-06-01

To evaluate the association between variables related to stress, reasons, and depression, and adherence to treatment in HIV-positive individuals, and to analyze the robustness according to a theoretical psychology model. This was a cross-sectional study of 25 female and 39 male HIV-positive participants receiving services at the Outpatient Center for Prevention and Treatment of HIV/AIDS and Sexually-transmitted Diseases (Centro Ambulatorio para la Prevención y Atención del VIH/Sida e Infecciones de Transmisión Sexual) in Hermosillo, Sonora, Mexico. The psychological variables, the degree of treatment adherence, stress-related circumstances, and the severity of depression were examined. Rates were calculated for the key variables associated with stress, reasons, and depression. The associations among variables were determined by multiple regression. During the month preceding the study, 65.6% of the 64 participants reported having faithfully followed the prescribed treatment, while 34.4% had failed, in some way, to follow the treatment (chi(2) = 6.250; P = 0.012). Regression analysis found that there was only one combination, an intermediate level of stress linked to tolerance of uncertainty and low levels of depression, that was significantly associated (F [3.58] = 3.298; P = 0.027) with adherence to treatment; the combination of these two variables explained 38.2% of the total variance found. The combination of stress levels with tolerance of uncertainty and depression could be used as a predictor for true compliance with prescribed treatment plans. These results should be taken into account when designing intervention and treatment-adherence campaigns in HIV-positive individuals.

Stability of Hand Force Production: II. Ascending and Descending Synergies.

PubMed

Reschechtko, Sasha; Latash, Mark L

2018-06-06

We combined the theory of neural control of movement with referent coordinates and the uncontrolled manifold hypothesis to investigate multi-finger coordination. We tested hypotheses related to stabilization of performance by co-varying control variables, translated into apparent stiffness and referent coordinate, at different levels of an assumed hierarchy of control. Subjects produced an accurate combination of total force and total moment of force with the four fingers under visual feedback on both variables and after feedback was partly or completely removed. The "inverse piano" device was used to estimate control variables. We observed strong synergies in the space of hypothetical control variables which stabilized total force and moment of force, as well as weaker synergies stabilizing individual finger forces; while the former were attenuated by alteration of visual feedback, the latter were much less affected. In addition, we investigated the organization of "ascending synergies" stabilizing task-level control variables by co-varied adjustments of finger-level control variables. We observed inter-trial co-variation of individual fingers' referent coordinates stabilizing hand-level referent coordinate, but observed no such co-variation for apparent stiffness. The observations suggest the existence of both descending and ascending synergies in a hierarchical control system. They confirm a trade-off between synergies at different levels of control and corroborate the hypothesis on specialization of different fingers for the control of force and moment. The results provide strong evidence for the importance of central back-coupling loops in ensuring stability of action.

Sociocultural and individual psychological predictors of body image in young girls: a prospective study.

PubMed

Clark, Levina; Tiggemann, Marika

2008-07-01

This study investigated the prospective predictors of body image in 9- to 12-year-old girls. Participants were 150 girls in Grades 4-6 with a mean age of 10.3 years. Girls completed questionnaire measures of media and peer influences (television/magazine exposure, peer appearance conversations), individual psychological variables (appearance schemas, internalization of appearance ideals, autonomy), and body image (figure discrepancy and body esteem) at Time 1 and 1 year later at Time 2. Linear panel analyses showed that after controlling for Time 1 levels of body image, none of the Time 1 sociocultural variables predicted body image variables at Time 2. Body mass index (BMI; a biological variable) and psychological variables, however, did offer significant prospective prediction. Specifically, higher BMI, higher appearance schemas, higher internalization of appearance ideals, and lower autonomy predicted worsening body image 1 year later. Thus, higher weight and certain psychological characteristics were temporally antecedent to body image concerns. It was concluded that both biological and individual psychological variables play a role in the development of body image in children. Individual psychological variables, in particular, may provide useful targets in prevention and intervention programs addressing body image in 9- to 12-year-old girls.

Does workplace social capital associate with hazardous drinking among Chinese rural-urban migrant workers?

PubMed

Gao, Junling; Weaver, Scott R; Fua, Hua; Pan, Zhigang

2014-01-01

The present study sought to investigate the associations between workplace social capital and hazardous drinking (HD) among Chinese rural-urban migrant workers (RUMW). A cross sectional study with a multi-stage stratified sampling procedure was conducted in Shanghai during July 2012 to January 2013. In total, 5,318 RUMWs from 77 workplaces were involved. Work-place social capital was assessed using a validated and psychometrically tested eight-item measure. The Chinese version of Alcohol Use Disorders Identification Test (AUDIT) was used to assess hazardous drinking. Control variables included gender, age, marital status, education level, salary, and current smoking. Multilevel logistic regression analysis was conducted to test whether individual- and workplace-level social capital was associated with hazardous drinking. Overall, the prevalence of HD was 10.6%. After controlling for individual-level socio-demographic and lifestyle variables, compared to workers in the highest quartile of individual-level social capital, the odds of HD for workers in the three bottom quartiles were 1.13(95%CI: 1.04-1.23), 1.17(95%CI: 1.05-1.56) and 1.26(95%CI: 1.13-1.72), respectively. However, contrary to hypothesis, there was no relationship between workplace-level social capital and hazardous drinking. Higher individual-level social capital may protect against HD among Chinese RUMWs. Interventions to build individual social capital among RUMWs in China may help reduce HD among this population.

Individual Differences in Childhood Sleep Problems Predict Later Cognitive Executive Control

PubMed Central

Friedman, Naomi P.; Corley, Robin P.; Hewitt, John K.; Wright, Kenneth P.

2009-01-01

Study Objective: To determine whether individual differences in developmental patterns of general sleep problems are associated with 3 executive function abilities—inhibiting, updating working memory, and task shifting—in late adolescence. Participants: 916 twins (465 female, 451 male) and parents from the Colorado Longitudinal Twin Study. Measurements and Results: Parents reported their children's sleep problems at ages 4 years, 5 y, 7 y, and 9–16 y based on a 7-item scale from the Child-Behavior Checklist; a subset of children (n = 568) completed laboratory assessments of executive functions at age 17. Latent variable growth curve analyses were used to model individual differences in longitudinal trajectories of childhood sleep problems. Sleep problems declined over time, with ~70% of children having ≥ 1 problem at age 4 and ~33% of children at age 16. However, significant individual differences in both the initial levels of problems (intercept) and changes across time (slope) were observed. When executive function latent variables were added to the model, the intercept did not significantly correlate with the later executive function latent variables; however, the slope variable significantly (P < 0.05) negatively correlated with inhibiting (r = −0.27) and updating (r = −0.21), but not shifting (r = −0.10) abilities. Further analyses suggested that the slope variable predicted the variance common to the 3 executive functions (r = −0.29). Conclusions: Early levels of sleep problems do not seem to have appreciable implications for later executive functioning. However, individuals whose sleep problems decrease more across time show better general executive control in late adolescence. Citation: Friedman NP; Corley RP; Hewitt JK; Wright KP. Individual differences in childhood sleep problems predict later cognitive executive control. SLEEP 2009;32(3):323-333. PMID:19294952

Examination of the Job Satisfaction of Teachers Working with Individuals in Need of Special Education with Regard to Certain Variables*

ERIC Educational Resources Information Center

Yavuz, Mehmet

2018-01-01

In this study, the job satisfaction levels of teachers working with individuals in need of special education were examined with regard to certain variables. General survey model was used in the study and the study group of this research was comprised of teachers from all over Turkey who work at special education schools, integration and special…

Individual relocation decisions after tornadoes: a multi-level analysis.

PubMed

Cong, Zhen; Nejat, Ali; Liang, Daan; Pei, Yaolin; Javid, Roxana J

2018-04-01

This study examines how multi-level factors affected individuals' relocation decisions after EF4 and EF5 (Enhanced Fujita Tornado Intensity Scale) tornadoes struck the United States in 2013. A telephone survey was conducted with 536 respondents, including oversampled older adults, one year after these two disaster events. Respondents' addresses were used to associate individual information with block group-level variables recorded by the American Community Survey. Logistic regression revealed that residential damage and homeownership are important predictors of relocation. There was also significant interaction between these two variables, indicating less difference between homeowners and renters at higher damage levels. Homeownership diminished the likelihood of relocation among younger respondents. Random effects logistic regression found that the percentage of homeownership and of higher income households in the community buffered the effect of damage on relocation; the percentage of older adults reduced the likelihood of this group relocating. The findings are assessed from the standpoint of age difference, policy implications, and social capital and vulnerability. © 2018 The Author(s). Disasters © Overseas Development Institute, 2018.

Correlates and predictors of sexual health among adolescent Latinas in the United States: A systematic review of the literature, 2004-2015.

PubMed

Morales-Alemán, Mercedes M; Scarinci, Isabel C

2016-06-01

Adolescent Latinas in the United States (US) are disproportionately affected by early pregnancy, sexually transmitted infections (STIs) and human immunodeficiency virus (HIV) in comparison to their non-Hispanic white counterparts. However, only a few studies have sought to understand the multi-level factors associated with sexual health in adolescent Latinas. Adhering to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, we conducted a systematic literature review to better understand the correlates and predictors of sexual health among adolescent Latinas in the US, identify gaps in the research, and suggest future directions for empirical studies and intervention efforts. Eleven studies were identified: five examined onset of sexual intercourse, nine examined determinants of sexual health/risk behaviors (e.g., number of sexual partners and condom use), and three examined determinants of a biological sexual health outcome (i.e., STIs or pregnancy). Two types of variables/factors emerged as important influences on sexual health outcomes: proximal context-level variables (i.e., variables pertaining to the individual's family, sexual/romantic partner or peer group) and individual-level variables (i.e., characteristics of the individual). A majority of the studies reviewed (n=9) examined some aspect of acculturation or Latino/a cultural values in relation to sexual health. Results varied widely between studies suggesting that the relationship between individual and proximal contextual variables (including acculturation) and sexual health may be more complex than previously conceived. This review integrates the findings on correlates and predictors of sexual health among adolescent Latinas, and supports the need for strengths-based theoretically guided research on the mechanisms driving these associations. Copyright © 2016 Elsevier Inc. All rights reserved.

Individual and contextual factors related to binge drinking among adolescents in Spain: a multilevel approach.

PubMed

Teixidó-Compañó, Ester; Sordo, Luis; Bosque-Prous, Marina; Puigcorbé, Susanna; Barrio, Gregorio; Brugal, M Teresa; Belza, María José J; Espelt, Albert

2018-01-15

The aim of this study was to estimate the prevalence of binge drinking by regions in Spain and assess the effect of individual and contextual factors related to this drinking pattern in adolescents. A cross-sectional study was performed with data from the 2014 Spanish School Survey on Drug Use (ESTUDES) in students aged 14-18 years (N = 34,259). The outcome was binge drinking in adolescents during the last 30 days. Individual independent variables were socioeconomic variables and variables related to access to alcohol and its availability. Contextual variables consisted of adult alcohol consumption, public policies on alcohol, and socioeconomic factors. Multilevel Poisson regression models with robust variance were estimated, obtaining prevalence ratios (PR) and their 95% confidence intervals.  The results showed that the prevalence of youth binge drinking by region of residence was similar for both sexes (r = 0.72). At the individual level, binge drinking was mainly associated with the perception of easy access to alcohol (PR: 1.38; 95% CI: 1.23-1.55), consumption in open areas [(PR: 3.82; 95% CI: 3.44-4.24) < once a month and (PR: 6.57; 95% CI: 5.85-7.37) ≥ once a month], at least one parent allowing alcohol consumption (PR: 1.42; 95% CI: 1.37-1.47), and receiving >30 euros weekly (PR :1.51; 95% CI: 1.37-1.67). Contextual variables were not associated with youth binge drinking when individual variables were considered. In conclusion, youth binge drinking was associated with individual variables related to high alcohol accessibility and availability, regardless of contextual variables. These variables explained the variability in binge drinking among Spanish regions.

Kinetic and Kinematic Differences in a Golf Swing in One and Both Lower Limb Amputees

PubMed Central

Stastny, Petr; Maszczyk, Adam; Tománková, Kristina; Kubový, Petr; Richtrová, Michaela; Otáhal, Jakub; Čichoň, Rostislav; Mostowik, Aleksandra; Żmijewski, Piotr; Cięszczyk, Paweł

2015-01-01

Amputee golfers need to cope with the absence of sole proprioception, a decreased range of swing motion and other factors which should be recognized for training purposes. The aim of this study was to determine the kinetic and kinematic differences in the golf swing in one leg and two legs amputees. The participants consisted of two males and one female at a professional or amateur level with a different degree of disability. Each participant was taped by 3D markers and performed five golf swings with the iron 6. The intraclass correlation coefficient (ICC) did not vary between individuals in kinematics, however, it was low in kinetic variables of two leg amputees. The Kendal rank correlation showed a significant relationship between the level of amputation and a large number of kinetic and kinematic variables such as X factor, O factor, S factor and individual body angles. The fluency and similarity of the golf swing did not depend on the level of amputation. One lower limb amputation did not seem to increase movement variability contrary to two lower limb amputation. The most variable parameter was a weight-shift in all golfers. The takeaway and horizontal force angle depended on the level of amputation rather than individual technique, thus, their modification by training may be difficult. Estimation of golf swing „mistakes” in amputees in respect to the leading arm in an early follow or late follow position appeared to be useless. PMID:26834871

Kinetic and Kinematic Differences in a Golf Swing in One and Both Lower Limb Amputees.

PubMed

Stastny, Petr; Maszczyk, Adam; Tománková, Kristina; Kubový, Petr; Richtrová, Michaela; Otáhal, Jakub; Čichoň, Rostislav; Mostowik, Aleksandra; Żmijewski, Piotr; Cięszczyk, Paweł

2015-11-22

Amputee golfers need to cope with the absence of sole proprioception, a decreased range of swing motion and other factors which should be recognized for training purposes. The aim of this study was to determine the kinetic and kinematic differences in the golf swing in one leg and two legs amputees. The participants consisted of two males and one female at a professional or amateur level with a different degree of disability. Each participant was taped by 3D markers and performed five golf swings with the iron 6. The intraclass correlation coefficient (ICC) did not vary between individuals in kinematics, however, it was low in kinetic variables of two leg amputees. The Kendal rank correlation showed a significant relationship between the level of amputation and a large number of kinetic and kinematic variables such as X factor, O factor, S factor and individual body angles. The fluency and similarity of the golf swing did not depend on the level of amputation. One lower limb amputation did not seem to increase movement variability contrary to two lower limb amputation. The most variable parameter was a weight-shift in all golfers. The takeaway and horizontal force angle depended on the level of amputation rather than individual technique, thus, their modification by training may be difficult. Estimation of golf swing "mistakes" in amputees in respect to the leading arm in an early follow or late follow position appeared to be useless.

Individual-level risk factors for gun victimization in a sample of probationers.

PubMed

Wells, William; Chermak, Steven

2011-07-01

Interventions aimed at preventing the important problem of gun injuries could be improved with an understanding of whether there are unique factors that place individuals at an increased risk of gun victimization. Much remains to be known about the victims of gun violence. The purpose of this article is to assess whether there are individual-level variables uniquely related to the likelihood of experiencing a gun victimization in a sample of probationers, individuals already at a heightened risk for criminal victimization. Self-report data were collected from 235 felony probationers about, for instance, gun and nongun victimization, gang involvement, and drug sales. Results show different variables are related to nongun victimization and gun victimization. In the current sample, involvement in gun crimes are linked to an increased risk of gun victimization. Violent offending and residential stability are associated with an increased chance of crime victimization.

Dissecting components of population-level variation in seed production and the evolution of masting behavior.

Treesearch

W. D. Koenig; D. Kelly; V. L. Sork; R. P. Duncan; J. S. Elkinton; M.S. Peltonen; R. D. Westfall

2003-01-01

Mast-fruiting or masting behavior is the cumulative result of the reproductive patterns of individuals within a population and thus involves components of individual variability, between-individual synchrony, and endogenous cycles of temporal autocorrelation. Extending prior work by Herrera, we explore the interrelationships of these components using data on individual...

Effect of national wealth on BMI: An analysis of 206,266 individuals in 70 low-, middle- and high-income countries

PubMed Central

Reidpath, Daniel D.

2017-01-01

Background This study explores the relationship between BMI and national-wealth and the cross-level interaction effect of national-wealth and individual household-wealth using multilevel analysis. Methods Data from the World Health Survey conducted in 2002–2004, across 70 low-, middle- and high-income countries was used. Participants aged 18 years and over were selected using multistage, stratified cluster sampling. BMI was used as outcome variable. The potential determinants of individual-level BMI were participants’ sex, age, marital-status, education, occupation, household-wealth and location(rural/urban) at the individual-level. The country-level factors used were average national income (GNI-PPP) and income inequality (Gini-index). A two-level random-intercepts and fixed-slopes model structure with individuals nested within countries was fitted, treating BMI as a continuous outcome. Results The weighted mean BMI and standard-error of the 206,266 people from 70-countries was 23.90 (4.84). All the low-income countries were below the 25.0 mean BMI level and most of the high-income countries were above. All wealthier quintiles of household-wealth had higher scores in BMI than lowest quintile. Each USD10000 increase in GNI-PPP was associated with a 0.4 unit increase in BMI. The Gini-index was not associated with BMI. All these variables explained 28.1% of country-level, 4.9% of individual-level and 7.7% of total variance in BMI. The cross-level interaction effect between GNI-PPP and household-wealth was significant. BMI increased as the GNI-PPP increased in first four quintiles of household-wealth. However, the BMI of the wealthiest people decreased as the GNI-PPP increased. Conclusion Both individual-level and country-level factors made an independent contribution to the BMI of the people. Household-wealth and national-income had significant interaction effects. PMID:28662041

Effect of national wealth on BMI: An analysis of 206,266 individuals in 70 low-, middle- and high-income countries.

PubMed

Masood, Mohd; Reidpath, Daniel D

2017-01-01

This study explores the relationship between BMI and national-wealth and the cross-level interaction effect of national-wealth and individual household-wealth using multilevel analysis. Data from the World Health Survey conducted in 2002-2004, across 70 low-, middle- and high-income countries was used. Participants aged 18 years and over were selected using multistage, stratified cluster sampling. BMI was used as outcome variable. The potential determinants of individual-level BMI were participants' sex, age, marital-status, education, occupation, household-wealth and location(rural/urban) at the individual-level. The country-level factors used were average national income (GNI-PPP) and income inequality (Gini-index). A two-level random-intercepts and fixed-slopes model structure with individuals nested within countries was fitted, treating BMI as a continuous outcome. The weighted mean BMI and standard-error of the 206,266 people from 70-countries was 23.90 (4.84). All the low-income countries were below the 25.0 mean BMI level and most of the high-income countries were above. All wealthier quintiles of household-wealth had higher scores in BMI than lowest quintile. Each USD10000 increase in GNI-PPP was associated with a 0.4 unit increase in BMI. The Gini-index was not associated with BMI. All these variables explained 28.1% of country-level, 4.9% of individual-level and 7.7% of total variance in BMI. The cross-level interaction effect between GNI-PPP and household-wealth was significant. BMI increased as the GNI-PPP increased in first four quintiles of household-wealth. However, the BMI of the wealthiest people decreased as the GNI-PPP increased. Both individual-level and country-level factors made an independent contribution to the BMI of the people. Household-wealth and national-income had significant interaction effects.

Overcoming ecologic bias using the two-phase study design.

PubMed

Wakefield, Jon; Haneuse, Sebastien J-P A

2008-04-15

Ecologic (aggregate) data are widely available and widely utilized in epidemiologic studies. However, ecologic bias, which arises because aggregate data cannot characterize within-group variability in exposure and confounder variables, can only be removed by supplementing ecologic data with individual-level data. Here the authors describe the two-phase study design as a framework for achieving this objective. In phase 1, outcomes are stratified by any combination of area, confounders, and error-prone (or discretized) versions of exposures of interest. Phase 2 data, sampled within each phase 1 stratum, provide accurate measures of exposure and possibly of additional confounders. The phase 1 aggregate-level data provide a high level of statistical power and a cross-classification by which individuals may be efficiently sampled in phase 2. The phase 2 individual-level data then provide a control for ecologic bias by characterizing the within-area variability in exposures and confounders. In this paper, the authors illustrate the two-phase study design by estimating the association between infant mortality and birth weight in several regions of North Carolina for 2000-2004, controlling for gender and race. This example shows that the two-phase design removes ecologic bias and produces gains in efficiency over the use of case-control data alone. The authors discuss the advantages and disadvantages of the approach.

Influence of neighbourhood purchasing power on breastfeeding at four months of age: a Swedish population-based cohort study.

PubMed

Almquist-Tangen, Gerd; Strömberg, Ulf; Holmén, Anders; Alm, Bernt; Roswall, Josefine; Bergman, Stefan; Dahlgren, Jovanna

2013-11-15

Parental socioeconomic status (SES) is an important determinant in child health, influencing beneficial factors such as breastfeeding. A better understanding of the influence of neighbourhood-level SES measures, relating to spatial determinants, might lead to targeted actions to promote breastfeeding during infancy. A cross-sectional study analysis the association between breastfeeding at four months of age and neighbourhood purchasing power, taking account of individual-level variables including maternal age, smoking and parental level of education. Data were obtained from a prospective population- based cohort study recruited from birth in 2007-2008 in the Halland region, southwestern Sweden. Questionnaire data on the individual-level variables and the outcome variable of breastfeeding at four months (yes/no) were used (n=2,407). Each mother was geo-coded with respect to her residential parish (there are 61 parishes in the region) and then stratified by parish-level household purchasing power. It emerged that four neighbourhood characteristics were reasonable to use, viz. <10%, 10-19%, 20-29% and ≥ 30% of the resident families with low purchasing power. The proportion of mothers not breastfeeding at four months of age showed a highly significant trend across the neighbourhood strata (p=0.00004): from 16.3% (< 10% with low purchasing power) to 29.4% (≥ 30% with low purchasing power), yielding an OR of 2.24 (95% confidence interval: 1.45-3.16). After adjusting for the individual-level variables, the corresponding OR=1.63 (1.07-2.56) was significant and the trend across the strata was still evident (p=0.05). A multi-level analysis estimated that, in the neighbourhoods with ≥ 30% of the families with low purchasing power, 20% more mothers than expected, taking account of the individual-level factors, reported no breastfeeding at four months of age (≥ 95% posterior probability of an elevated observed-to-expected ratio). The neighbourhood purchasing power provided a spatial determinant of low numbers of mothers breastfeeding at four months of age, which could be relevant to consider for targeted actions. The elevated observed-to-expected ratio in the neighbourhoods with the lowest purchasing power points toward a possible contextual influence.

Variable ecological conditions promote male helping by changing banded mongoose group composition.

PubMed

Marshall, Harry H; Sanderson, Jennifer L; Mwanghuya, Francis; Businge, Robert; Kyabulima, Solomon; Hares, Michelle C; Inzani, Emma; Kalema-Zikusoka, Gladys; Mwesige, Kenneth; Thompson, Faye J; Vitikainen, Emma I K; Cant, Michael A

2016-01-01

Ecological conditions are expected to have an important influence on individuals' investment in cooperative care. However, the nature of their effects is unclear: both favorable and unfavorable conditions have been found to promote helping behavior. Recent studies provide a possible explanation for these conflicting results by suggesting that increased ecological variability, rather than changes in mean conditions, promote cooperative care. However, no study has tested whether increased ecological variability promotes individual-level helping behavior or the mechanisms involved. We test this hypothesis in a long-term study population of the cooperatively breeding banded mongoose, Mungos mungo , using 14 years of behavioral and meteorological data to explore how the mean and variability of ecological conditions influence individual behavior, body condition, and survival. Female body condition was more sensitive to changes in rainfall leading to poorer female survival and pronounced male-biased group compositions after periods of high rainfall variability. After such periods, older males invested more in helping behavior, potentially because they had fewer mating opportunities. These results provide the first empirical evidence for increased individual helping effort in more variable ecological conditions and suggest this arises because of individual differences in the effect of ecological conditions on body condition and survival, and the knock-on effect on social group composition. Individual differences in sensitivity to environmental variability, and the impacts this has on the internal structure and composition of animal groups, can exert a strong influence on the evolution and maintenance of social behaviors, such as cooperative care.

Association between income inequality and dental status in Japanese older adults: Analysis of data from JAGES2013.

PubMed

Tashiro, Atsushi; Aida, Jun; Shobugawa, Yugo; Fujiyama, Yuki; Yamamoto, Tatsuo; Saito, Reiko; Kondo, Katsunori

2017-01-01

Objectives　Personal income affects dental status in older people. However, the impact of income inequality on dental status at the community level (junior high school district) is unclear. The purpose of this study was to examine the association between dental status and community level income inequity after adjust for individual socio-economic status in Japanese older adults, and to verify the relative income hypothesis, also known as the Wilkinson hypothesis.Methods　We used data from the Japan Gerontological Evaluation Study (JAGES) conducted in Niigata city. JAGES is a postal survey of functionally independent adults aged 65 years or older. We enrolled 4,983 respondents (response rate 62.3%) and used data on 3,980 of them after excluding incomplete data. We evaluated health condition and socio-economic status using questionnaires. The Gini coefficient, as an indicator of income inequality, was calculated by junior high school district (57 districts) based on the data from the questionnaire. Additionally, the Pearson's coefficient of correlation was calculated to evaluate the association between the mean number of remaining teeth and the community level Gini coefficient. Then we evaluated the mean number of remaining teeth among the groups stratified by the Gini coefficient conditions. Next, we conducted a multilevel analysis using an ordinal logistic regression model. The number of remaining teeth was set as the dependent variable, while sex, age, household size, education, smoking status, diabetes treatment, current living conditions, and equivalent income were used as independent variables at the individual level. The Gini coefficient and average equivalent income in the junior high school district were used as independent variables at the community level.Results　The Pearson's correlation coefficient for the relationship between the Gini coefficient and the mean number of remaining teeth in the junior high school district was -0.44 (P<0.01). Wider income disparity area (Gini coefficient≧0.35) revealed a significantly small number of remaining teeth (P<0.001). The multilevel analysis showed that a higher Gini coefficient and a lower average equivalent income at the community level were significantly associated with a lower number of remaining teeth, and with educational attainment, smoking status, current living conditions, and equivalent income at the individual level, after adjusting for sex and age. On the other hand, educational attainment at the individual level, and average equivalent income at the community level were not significant factors after adjusting for all individual level variables.Conclusion　This study showed that, in addition to individual socio-economic status, income inequality at the community level was significantly associated with number of remaining teeth in Japanese older adults. Although the precise mechanism of this association is still unclear, our result supports the relative income hypothesis.

Individual differences and time-varying features of modular brain architecture.

PubMed

Liao, Xuhong; Cao, Miao; Xia, Mingrui; He, Yong

2017-05-15

Recent studies have suggested that human brain functional networks are topologically organized into functionally specialized but inter-connected modules to facilitate efficient information processing and highly flexible cognitive function. However, these studies have mainly focused on group-level network modularity analyses using "static" functional connectivity approaches. How these extraordinary modular brain structures vary across individuals and spontaneously reconfigure over time remain largely unknown. Here, we employed multiband resting-state functional MRI data (N=105) from the Human Connectome Project and a graph-based modularity analysis to systematically investigate individual variability and dynamic properties in modular brain networks. We showed that the modular structures of brain networks dramatically vary across individuals, with higher modular variability primarily in the association cortex (e.g., fronto-parietal and attention systems) and lower variability in the primary systems. Moreover, brain regions spontaneously changed their module affiliations on a temporal scale of seconds, which cannot be simply attributable to head motion and sampling error. Interestingly, the spatial pattern of intra-subject dynamic modular variability largely overlapped with that of inter-subject modular variability, both of which were highly reproducible across repeated scanning sessions. Finally, the regions with remarkable individual/temporal modular variability were closely associated with network connectors and the number of cognitive components, suggesting a potential contribution to information integration and flexible cognitive function. Collectively, our findings highlight individual modular variability and the notable dynamic characteristics in large-scale brain networks, which enhance our understanding of the neural substrates underlying individual differences in a variety of cognition and behaviors. Copyright © 2017 Elsevier Inc. All rights reserved.

Individualism and collectivism: cultural orientation in locus of control and moral attribution under conditions of social change.

PubMed

Santiago, Jose H; Tarantino, Santo J

2002-12-01

This study examined the validity of the view that the constructs of individualism and collectivism are coherent cultural manifestations necessarily reflected in an individual's attribution patterns. It was hypothesized that the attribution patterns of locus of control and moral accountability would show divergent individualistic and collectivistic influences in a culture during change from a collectivist culture to an individualist culture. 98 university students from the United States and Puerto Rico were administered the Singelis Individualism-Collectivism Scale, Rotter's Locus of Control Scale, and Miller and Luthar's justice-related moral accountability vignettes. Contrary to expectation, the Puerto Rican sample scored less external in locus of control than the United States sample. No cultural differences in moral accountability were found. No strong correlations were found among the variables at the individual level of analysis. Accounting for these results included the lack of representativeness of the samples, the independence of relation between variables at different levels of analysis, and social change.

Quantifying Individual Brain Connectivity with Functional Principal Component Analysis for Networks.

PubMed

Petersen, Alexander; Zhao, Jianyang; Carmichael, Owen; Müller, Hans-Georg

2016-09-01

In typical functional connectivity studies, connections between voxels or regions in the brain are represented as edges in a network. Networks for different subjects are constructed at a given graph density and are summarized by some network measure such as path length. Examining these summary measures for many density values yields samples of connectivity curves, one for each individual. This has led to the adoption of basic tools of functional data analysis, most commonly to compare control and disease groups through the average curves in each group. Such group differences, however, neglect the variability in the sample of connectivity curves. In this article, the use of functional principal component analysis (FPCA) is demonstrated to enrich functional connectivity studies by providing increased power and flexibility for statistical inference. Specifically, individual connectivity curves are related to individual characteristics such as age and measures of cognitive function, thus providing a tool to relate brain connectivity with these variables at the individual level. This individual level analysis opens a new perspective that goes beyond previous group level comparisons. Using a large data set of resting-state functional magnetic resonance imaging scans, relationships between connectivity and two measures of cognitive function-episodic memory and executive function-were investigated. The group-based approach was implemented by dichotomizing the continuous cognitive variable and testing for group differences, resulting in no statistically significant findings. To demonstrate the new approach, FPCA was implemented, followed by linear regression models with cognitive scores as responses, identifying significant associations of connectivity in the right middle temporal region with both cognitive scores.

Variability in PAH-DNA adduct measurements in peripheral mononuclear cells: implications for quantitative cancer risk assessment.

PubMed

Dickey, C; Santella, R M; Hattis, D; Tang, D; Hsu, Y; Cooper, T; Young, T L; Perera, F P

1997-10-01

Biomarkers such as DNA adducts have significant potential to improve quantitative risk assessment by characterizing individual differences in metabolism of genotoxins and DNA repair and accounting for some of the factors that could affect interindividual variation in cancer risk. Inherent uncertainty in laboratory measurements and within-person variability of DNA adduct levels over time are putatively unrelated to cancer risk and should be subtracted from observed variation to better estimate interindividual variability of response to carcinogen exposure. A total of 41 volunteers, both smokers and nonsmokers, were asked to provide a peripheral blood sample every 3 weeks for several months in order to specifically assess intraindividual variability of polycyclic aromatic hydrocarbon (PAH)-DNA adduct levels. The intraindividual variance in PAH-DNA adduct levels, together with measurement uncertainty (laboratory variability and unaccounted for differences in exposure), constituted roughly 30% of the overall variance. An estimated 70% of the total variance was contributed by interindividual variability and is probably representative of the true biologic variability of response to carcinogenic exposure in lymphocytes. The estimated interindividual variability in DNA damage after subtracting intraindividual variability and measurement uncertainty was 24-fold. Inter-individual variance was higher (52-fold) in persons who constitutively lack the Glutathione S-Transferase M1 (GSTM1) gene which is important in the detoxification pathway of PAH. Risk assessment models that do not consider the variability of susceptibility to DNA damage following carcinogen exposure may underestimate risks to the general population, especially for those people who are most vulnerable.

Linking hearing impairment, employment and education.

PubMed

Garramiola-Bilbao, I; Rodríguez-Álvarez, A

2016-12-01

To analyse the impact that hearing impairment and other relevant variables have on the education and employment situation of those affected by it in the Principality of Asturias, Spain. To achieve this objective, two discrete choice models (probit) are presented. The first one associates, among other variables, hearing impairment with the individual's employment status and in the second model, an ordered multinomial probit model is used to analyse, among other variables, how the impairment affects the individual's level of studies. Although the levels of statistical significance are low, the model's estimates appear to indicate that hearing impairment in Spain increases the probability of being unemployed by 18.4% (P = 0.09). Additionally, the people suffering from such a disability are, compared with the rest of the population, 10.2% (P = 0.05) more likely to have only completed elementary studies without pursuing any further education. If an individual is able to reach a level of secondary or higher education thus enabling a future incorporation to the work place, a benefit is obviously generated for both the individual as well as society (which has additionally incurred an investment in human capital). In this regard, encouraging the education of hearing-impaired students would profit both the individual (who receives an early integration as a child), which may contribute positively to family and social factors, as well as society who have incurred the investment. Therefore, our result could indicate that programmes created to support individuals with this type of disability represent an increase of welfare both individually and socially. Copyright © 2016 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Public perceptions of animal experimentation across Europe.

PubMed

von Roten, Fabienne Crettaz

2013-08-01

The goal of this article is to map out public perceptions of animal experimentation in 28 European countries. Postulating cross-cultural differences, this study mixes country-level variables (from the Eurostat database) and individual-level variables (from Eurobarometer Science and Technology 2010). It is shown that experimentation on animals such as mice is generally accepted in European countries, but perceptions are divided on dogs and monkeys. Between 2005 and 2010, we observe globally a change of approval on dogs and monkeys, with a significant decrease in nine countries. Multilevel analysis results show differences at country level (related to a post-industrialism model) and at individual level (related to gender, age, education, proximity and perceptions of science and the environment). These results may have consequences for public perceptions of science and we call for more cross-cultural research on press coverage of animal research and on the level of public engagement of scientists doing animal research.

Individual and county level predictors of asthma related emergency department visits among children on Medicaid: A multilevel approach.

PubMed

Baltrus, Peter; Xu, Junjun; Immergluck, Lilly; Gaglioti, Anne; Adesokan, Adeola; Rust, George

2017-01-02

Disparities in asthma outcomes are well documented in the United States. Interventions to promote equity in asthma outcomes could target factors at the individual and community levels. The objective of this analysis was to understand the effect of individual (race, gender, age, and preventive inhaler use) and county-level factors (demographic, socioeconomic, health care, air-quality) on asthma emergency department (ED) visits among Medicaid-enrolled children. This was a retrospective cohort study of Medicaid-enrolled children with asthma in 29 states in 2009. Multilevel regression models of asthma ED visits were constructed utilizing individual-level variables (race, gender, age, and preventive inhaler use) from the Medicaid enrollment file and county-level variables reflecting population and health system characteristics from the Area Resource File (ARF). County-level measures of air quality were obtained from Environmental Protection Agency (EPA) data. The primary modifiable risk factor at the individual level was found to be the ratio of long-term controller medications to total asthma medications. County-level factors accounted for roughly 6% of the variance in the asthma ED visit risk. Increasing county-level racial segregation (OR=1.04, 95% CI=1.01-1.08) was associated with increasing risk of asthma ED visits. Greater supply of pulmonary physicians at the county level (OR=0.81, 95% CI=0.68-0.97) was associated with a reduction in risk of asthma ED visits. At the patient care level, proper use of controller medications is the factor most amenable to intervention. There is also a societal imperative to address negative social determinants, such as residential segregation.

Individual and contextual determinants of regional variation in prescription drug use: an analysis of administrative data from British Columbia.

PubMed

Morgan, Steven G; Cunningham, Colleen M; Hanley, Gillian E

2010-12-29

Increasing attention is being paid to variations in the use of prescription drugs because their role in health care has grown to the point where their use can be considered a proxy for health system performance. Studies have shown that prescription drug use varies across regions in the US, UK, and Canada by more than would be predicted based on age and health status alone. In this paper, we explore the determinants of variations in the use of prescription drugs, drawing on health services theories of access to care. We conducted a cross-sectional analysis using population-based administrative health care data for British Columbia (BC), Canada. We used logistic and hierarchical regressions to analyze the effects of individual- and area-level determinants of use of prescriptions overall and rates of purchase of prescriptions from five therapeutic categories representing a range of indications: antihypertensives, statins, acid reducing drugs, opioid drugs, and antidepressants. To indicate the relative scale of regional variations and the importance of individual- and area-level variables in explaining them, we computed standardized rates of utilization for 49 local health areas in BC. We found that characteristics of individuals and the areas in which they live affect likelihood of prescription drug purchase. Individual-level factors influenced prescription drug purchases in ways generally consistent with behavioral models of health services use. Contextual variables exerted influences that differed by type of drug studied. Population health, education levels, and ethnic composition of local areas were associated with significant differences in the likelihood of purchasing medications. Relatively modest regional variations remained after both individual-level and area-level determinants were taken into account. The results of this study suggest that individual- and area-level factors should be considered when studying variations in the use of prescription drugs. Some sources of such variations, including individual- and area-level socioeconomic status, warrant further investigation and possible intervention to address inequities.

Individual and Contextual Determinants of Regional Variation in Prescription Drug Use: An Analysis of Administrative Data from British Columbia

PubMed Central

Morgan, Steven G.; Cunningham, Colleen M.; Hanley, Gillian E.

2010-01-01

Background Increasing attention is being paid to variations in the use of prescription drugs because their role in health care has grown to the point where their use can be considered a proxy for health system performance. Studies have shown that prescription drug use varies across regions in the US, UK, and Canada by more than would be predicted based on age and health status alone. In this paper, we explore the determinants of variations in the use of prescription drugs, drawing on health services theories of access to care. Methods We conducted a cross-sectional analysis using population-based administrative health care data for British Columbia (BC), Canada. We used logistic and hierarchical regressions to analyze the effects of individual- and area-level determinants of use of prescriptions overall and rates of purchase of prescriptions from five therapeutic categories representing a range of indications: antihypertensives, statins, acid reducing drugs, opioid drugs, and antidepressants. To indicate the relative scale of regional variations and the importance of individual- and area-level variables in explaining them, we computed standardized rates of utilization for 49 local health areas in BC. Results We found that characteristics of individuals and the areas in which they live affect likelihood of prescription drug purchase. Individual-level factors influenced prescription drug purchases in ways generally consistent with behavioral models of health services use. Contextual variables exerted influences that differed by type of drug studied. Population health, education levels, and ethnic composition of local areas were associated with significant differences in the likelihood of purchasing medications. Relatively modest regional variations remained after both individual-level and area-level determinants were taken into account. Conclusions The results of this study suggest that individual- and area-level factors should be considered when studying variations in the use of prescription drugs. Some sources of such variations, including individual- and area-level socioeconomic status, warrant further investigation and possible intervention to address inequities. PMID:21209960

An Examination of Individual Level Factors in Stress and Coping Processes: Perspectives of Chinese International Students in the United States

ERIC Educational Resources Information Center

Yan, Kun; Berliner, David C.

2011-01-01

No empirical research has focused solely upon understanding the stress and coping processes of Chinese international students in the United States. This qualitative inquiry examines the individual-level variables that affect the stress-coping process of Chinese international students and how they conceptualize and adapt to their stress at an…

An Analysis of Internet Addiction Levels of Individuals according to Various Variables

ERIC Educational Resources Information Center

Sahin, Cengiz

2011-01-01

The concept of internet addiction refers to the excessive use of internet which in turn causes various problems in individual, social and professional aspects. The aim of this study was to determine internet addiction levels of internet users from all age groups. The study used survey model. Study group of the study consisted of a total of 596…

Implications of supermarket access, neighbourhood walkability and poverty rates for diabetes risk in an employee population.

PubMed

Herrick, Cynthia J; Yount, Byron W; Eyler, Amy A

2016-08-01

Diabetes is a growing public health problem, and the environment in which people live and work may affect diabetes risk. The goal of the present study was to examine the association between multiple aspects of environment and diabetes risk in an employee population. This was a retrospective cross-sectional analysis. Home environment variables were derived using employees' zip code. Descriptive statistics were run on all individual- and zip-code-level variables, stratified by diabetes risk and worksite. A multivariable logistic regression analysis was then conducted to determine the strongest associations with diabetes risk. Data were collected from employee health fairs in a Midwestern health system, 2009-2012. The data set contains 25 227 unique individuals across four years of data. From this group, using an individual's first entry into the database, 15 522 individuals had complete data for analysis. The prevalence of high diabetes risk in this population was 2·3 %. There was significant variability in individual- and zip-code-level variables across worksites. From the multivariable analysis, living in a zip code with higher percentage of poverty and higher walk score was positively associated with high diabetes risk, while living in a zip code with higher supermarket density was associated with a reduction in high diabetes risk. Our study underscores the important relationship between poverty, home neighbourhood environment and diabetes risk, even in a relatively healthy employed population, and suggests a role for the employer in promoting health.

Effect of baseline plasma fatty acids on eicosapentaenoic acid levels in individuals supplemented with alpha-linolenic acid.

PubMed

DeFilippis, Andrew P; Harper, Charles R; Cotsonis, George A; Jacobson, Terry A

2009-01-01

We previously reported a >50% increase in mean plasma eicosapentaenoic acid levels in a general medicine clinic population after supplementation with alpha-linolenic acid. In the current analysis, we evaluate the variability of changes in eicosapentaenoic acid levels among individuals supplemented with alpha-linolenic acid and evaluated the impact of baseline plasma fatty acids levels on changes in eicosapentaenoic acid levels in these individuals. Changes in eicosapentaenoic acid levels among individuals supplemented with alpha-linolenic acid ranged from a 55% decrease to a 967% increase. Baseline plasma fatty acids had no statistically significant effect on changes in eicosapentaenoic levels acid after alpha-linolenic acid supplementation. Changes in eicosapentaenoic acid levels varied considerably in a general internal medicine clinic population supplemented with alpha-linolenic acid. Factors that may impact changes in plasma eicosapentaenoic acid levels after alpha-linolenic acid supplementation warrant further study.

The individualistic fallacy, ecological studies and instrumental variables: a causal interpretation.

PubMed

Loney, Tom; Nagelkerke, Nico J

2014-01-01

The validity of ecological studies in epidemiology for inferring causal relationships has been widely challenged as observed associations could be biased by the Ecological Fallacy. We reconsider the important design components of ecological studies, and discuss the conditions that may lead to spurious associations. Ecological associations are useful and valid when the ecological exposures can be interpreted as Instrumental Variables. A suitable example may be a time series analysis of environmental pollution (e.g. particulate matter with an aerodynamic diameter of <10 micrometres; PM10) and health outcomes (e.g. hospital admissions for acute myocardial infarction) as environmental pollution levels are a cause of individual exposure levels and not just an aggregate measurement. Ecological exposures may also be employed in situations (perhaps rare) where individual exposures are known but their associations with health outcomes are confounded by unknown or unquantifiable factors. Ecological associations have a notorious reputation in epidemiology and individualistic associations are considered superior to ecological associations because of the "ecological fallacy". We have argued that this is incorrect in situations in which ecological or aggregate exposures can serve as an instrumental variable and associations between individual exposure and outcome are likely to be confounded by unmeasured variables.

Multilevel analyses of school and children's characteristics associated with physical activity.

PubMed

Gomes, Thayse Natacha; dos Santos, Fernanda K; Zhu, Weimo; Eisenmann, Joey; Maia, José A R

2014-10-01

Children spend most of their awake time at school, and it is important to identify individual and school-level correlates of their physical activity (PA) levels. This study aimed to identify the between-school variability in Portuguese children PA and to investigate student and school PA correlates using multilevel modeling. The sample included 1075 Portuguese children of both sexes, aged 6-10 years, from 24 schools. Height and weight were measured and body mass index (BMI) was estimated. Physical activity was estimated using the Godin and Shephard questionnaire (total PA score was used); cardiorespiratory fitness was estimated with the 1-mile run/walk test. A structured inventory was used to access information about the school environment. A multilevel analysis (level-1: student-level; level-2: school-level) was used. Student-level variables (age, sex, 1-mile run/walk test) explained 7% of the 64% variance fraction of the individual-level PA; however, school context explained approximately 36% of the total PA variance. Variables included in the model (school size, school setting, playground area, frequency and duration of physical education class, and qualification of physical education teacher) are responsible for 80% of the context variance. School environment is an important correlate of PA among children, enhancing children's opportunities for being active and healthy. © 2014, American School Health Association.

Baseline Chromatin Modification Levels May Predict Interindividual Variability in Ozone-Induced Gene Expression

EPA Science Inventory

Traditional toxicological paradigms have relied on factors such as age, genotype, and disease status to explain variability in responsiveness to toxicant exposure; however, these are neither sufficient to faithfully identify differentially responsive individuals nor are they modi...

Does Workplace Social Capital Associate with Hazardous Drinking Among Chinese Rural-Urban Migrant Workers?

PubMed Central

Gao, Junling; Weaver, Scott R.; Fua, Hua; Pan, Zhigang

2014-01-01

Background The present study sought to investigate the associations between workplace social capital and hazardous drinking (HD) among Chinese rural-urban migrant workers (RUMW). Methods A cross sectional study with a multi-stage stratified sampling procedure was conducted in Shanghai during July 2012 to January 2013. In total, 5,318 RUMWs from 77 workplaces were involved. Work-place social capital was assessed using a validated and psychometrically tested eight-item measure. The Chinese version of Alcohol Use Disorders Identification Test (AUDIT) was used to assess hazardous drinking. Control variables included gender, age, marital status, education level, salary, and current smoking. Multilevel logistic regression analysis was conducted to test whether individual- and workplace-level social capital was associated with hazardous drinking. Results Overall, the prevalence of HD was 10.6%. After controlling for individual-level socio-demographic and lifestyle variables, compared to workers in the highest quartile of individual-level social capital, the odds of HD for workers in the three bottom quartiles were 1.13(95%CI: 1.04–1.23), 1.17(95%CI: 1.05–1.56) and 1.26(95%CI: 1.13–1.72), respectively. However, contrary to hypothesis, there was no relationship between workplace-level social capital and hazardous drinking. Conclusions Higher individual-level social capital may protect against HD among Chinese RUMWs. Interventions to build individual social capital among RUMWs in China may help reduce HD among this population. PMID:25502013

Preventing cold-related morbidity and mortality in a changing climate

PubMed Central

Conlon, Kathryn C; Rajkovich, Nicholas B; White-Newsome, Jalonne L; Larsen, Larissa; Neill, Marie S O

2011-01-01

Winter weather patterns are anticipated to become more variable with increasing average global temperatures. Research shows that excess morbidity and mortality occurs during cold weather periods. We critically reviewed evidence relating temperature variability, health outcomes, and adaptation strategies to cold weather. Health outcomes included cardiovascular-, respiratory-, cerebrovascular-, and all-cause morbidity and mortality. Individual and contextual risk factors were assessed to highlight associations between individual- and neighborhood- level characteristics that contribute to a person’s vulnerability to variability in cold weather events. Epidemiologic studies indicate that the populations most vulnerable to variations in cold winter weather are the elderly, rural and, generally, populations living in moderate winter climates. Fortunately, cold-related morbidity and mortality are preventable and strategies exist for protecting populations from these adverse health outcomes. We present a range of adaptation strategies that can be implemented at the individual, building, and neighborhood level to protect vulnerable populations from cold-related morbidity and mortality. The existing research justifies the need for increased outreach to individuals and communities for education on protective adaptations in cold weather. We propose that future climate change adaptation research couple building energy and thermal comfort models with epidemiological data to evaluate and quantify the impacts of adaptation strategies. PMID:21592693

Physiologic correlates to background noise acceptance

NASA Astrophysics Data System (ADS)

Tampas, Joanna; Harkrider, Ashley; Nabelek, Anna

2004-05-01

Acceptance of background noise can be evaluated by having listeners indicate the highest background noise level (BNL) they are willing to accept while following the words of a story presented at their most comfortable listening level (MCL). The difference between the selected MCL and BNL is termed the acceptable noise level (ANL). One of the consistent findings in previous studies of ANL is large intersubject variability in acceptance of background noise. This variability is not related to age, gender, hearing sensitivity, personality, type of background noise, or speech perception in noise performance. The purpose of the current experiment was to determine if individual differences in physiological activity measured from the peripheral and central auditory systems of young female adults with normal hearing can account for the variability observed in ANL. Correlations between ANL and various physiological responses, including spontaneous, click-evoked, and distortion-product otoacoustic emissions, auditory brainstem and middle latency evoked potentials, and electroencephalography will be presented. Results may increase understanding of the regions of the auditory system that contribute to individual noise acceptance.

Language Shift in the United States and Foreign-Born Older Mexican Heritage Individuals: Co-ethnic Context for Language Resistance

PubMed Central

Siordia, Carlos; Díaz, María E.

2014-01-01

In this study, we investigate individual-level language shift in a population of Mexican origin Latinos/as aged 65 and up. By using data from the Hispanic Established Populations for the Epidemiologic Study of the Elderly, we investigate their English language use as the dependent variable in a hierarchical linear model. The microlevel independent continuous variable is their level of contact with “Anglos”; the macrolevel continuous independent variable is the percentage of Mexicans in tract of residence. After accounting for their generational status, other microlevel social and health covariates, and tract-level attributes, we found a direct relationship between contact with Anglos and a “shift” toward more English language use, where as co-ethnic concentration increases, the influence of contact with Anglos decreases. We frame this article with a discussion on language shifting, and explain how co-ethnic concentration may provide the resources for engaging in a language resistance. PMID:25104874

The role of transcriptome resilience in resistance of corals to bleaching.

PubMed

Seneca, Francois O; Palumbi, Stephen R

2015-04-01

Wild populations increasingly experience extreme conditions as climate change amplifies environmental variability. How individuals respond to environmental extremes determines the impact of climate change overall. The variability of response from individual to individual can represent the opportunity for natural selection to occur as a result of extreme conditions. Here, we experimentally replicated the natural exposure to extreme temperatures of the reef lagoon at Ofu Island (American Samoa), where corals can experience severe heat stress during midday low tide. We investigated the bleaching and transcriptome response of 20 Acropora hyacinthus colonies 5 and 20 h after exposure to control (29 °C) or heated (35 °C) conditions. We found a highly dynamic transcriptome response: 27% of the coral transcriptome was significantly regulated 1 h postheat exposure. Yet 15 h later, when heat-induced coral bleaching became apparent, only 12% of the transcriptome was differentially regulated. A large proportion of responsive genes at the first time point returned to control levels, others remained differentially expressed over time, while an entirely different subset of genes was successively regulated at the second time point. However, a noteworthy variability in gene expression was observed among individual coral colonies. Among the genes of which expression lingered over time, fast return to normal levels was associated with low bleaching. Colonies that maintained higher expression levels of these genes bleached severely. Return to normal levels of gene expression after stress has been termed transcriptome resilience, and in the case of some specific genes may signal the physiological health and response ability of individuals to environmental stress. © 2015 John Wiley & Sons Ltd.

Human Occipital and Parietal GABA Selectively Influence Visual Perception of Orientation and Size.

PubMed

Song, Chen; Sandberg, Kristian; Andersen, Lau Møller; Blicher, Jakob Udby; Rees, Geraint

2017-09-13

GABA is the primary inhibitory neurotransmitter in human brain. The level of GABA varies substantially across individuals, and this variability is associated with interindividual differences in visual perception. However, it remains unclear whether the association between GABA level and visual perception reflects a general influence of visual inhibition or whether the GABA levels of different cortical regions selectively influence perception of different visual features. To address this, we studied how the GABA levels of parietal and occipital cortices related to interindividual differences in size, orientation, and brightness perception. We used visual contextual illusion as a perceptual assay since the illusion dissociates perceptual content from stimulus content and the magnitude of the illusion reflects the effect of visual inhibition. Across individuals, we observed selective correlations between the level of GABA and the magnitude of contextual illusion. Specifically, parietal GABA level correlated with size illusion magnitude but not with orientation or brightness illusion magnitude; in contrast, occipital GABA level correlated with orientation illusion magnitude but not with size or brightness illusion magnitude. Our findings reveal a region- and feature-dependent influence of GABA level on human visual perception. Parietal and occipital cortices contain, respectively, topographic maps of size and orientation preference in which neural responses to stimulus sizes and stimulus orientations are modulated by intraregional lateral connections. We propose that these lateral connections may underlie the selective influence of GABA on visual perception. SIGNIFICANCE STATEMENT GABA, the primary inhibitory neurotransmitter in human visual system, varies substantially across individuals. This interindividual variability in GABA level is linked to interindividual differences in many aspects of visual perception. However, the widespread influence of GABA raises the question of whether interindividual variability in GABA reflects an overall variability in visual inhibition and has a general influence on visual perception or whether the GABA levels of different cortical regions have selective influence on perception of different visual features. Here we report a region- and feature-dependent influence of GABA level on human visual perception. Our findings suggest that GABA level of a cortical region selectively influences perception of visual features that are topographically mapped in this region through intraregional lateral connections. Copyright © 2017 Song, Sandberg et al.

Patient or treatment centre? Where are efforts invested to improve cancer patients' psychosocial outcomes?

PubMed Central

Carey, ML; Clinton-McHarg, T; Sanson-Fisher, RW; Campbell, S; Douglas, HE

2011-01-01

The psychosocial outcomes of cancer patients may be influenced by individual-level, social and treatment centre predictors. This paper aimed to examine the extent to which individual, social and treatment centre variables have been examined as predictors or targets of intervention for psychosocial outcomes of cancer patients. Medline was searched to find studies in which the psychological outcomes of cancer patient were primary variables. Papers published in English between 1999 and 2009 that reported primary data relevant to psychosocial outcomes for cancer patients were included, with 20% randomly selected for further coding. Descriptive studies were coded for inclusion of individual, social or treatment centre variables. Intervention studies were coded to determine if the unit of intervention was the individual patient, social unit or treatment centre. After random sampling, 412 publications meeting the inclusion criteria were identified, 169 were descriptive and 243 interventions. Of the descriptive papers 95.0% included individual predictors, and 5.0% social predictors. None of the descriptive papers examined treatment centre variables as predictors of psychosocial outcomes. Similarly, none of the interventions evaluated the effectiveness of treatment centre interventions for improving psychosocial outcomes. Potential reasons for the overwhelming dominance of individual predictors and individual-focused interventions in psychosocial literature are discussed. PMID:20646035

ESTIMATING PERSON-CENTERED TREATMENT (PeT) EFFECTS USING INSTRUMENTAL VARIABLES: AN APPLICATION TO EVALUATING PROSTATE CANCER TREATMENTS

PubMed Central

BASU, ANIRBAN

2014-01-01

SUMMARY This paper builds on the methods of local instrumental variables developed by Heckman and Vytlacil (1999, 2001, 2005) to estimate person-centered treatment (PeT) effects that are conditioned on the person’s observed characteristics and averaged over the potential conditional distribution of unobserved characteristics that lead them to their observed treatment choices. PeT effects are more individualized than conditional treatment effects from a randomized setting with the same observed characteristics. PeT effects can be easily aggregated to construct any of the mean treatment effect parameters and, more importantly, are well suited to comprehend individual-level treatment effect heterogeneity. The paper presents the theory behind PeT effects, and applies it to study the variation in individual-level comparative effects of prostate cancer treatments on overall survival and costs. PMID:25620844

Conflict, social support, and relationship quality: an observational study of heterosexual, gay male, and lesbian couples' communication.

PubMed

Julien, Danielle; Chartrand, Elise; Simard, Marie-Claude; Bouthillier, Donald; Bégin, Jean

2003-09-01

Data from 42 heterosexual, 46 gay male, and 33 lesbian couples were used to assess the contribution of conflict and support discussions to relationship quality. Couples completed questionnaires, and videotaped discussions were coded for levels of negative and positive behaviors. Correlations showed that behaviors were associated with relationship quality in the expected directions. Hierarchical linear modeling analyses assessed the unique contributions of individual and dyadic behaviors to the variability of relationship quality. The findings indicated that, beyond the contribution of individual negative behaviors in the conflict task, the variables of dyadic positive behaviors in the conflict task, individual positive behaviors in the support task, and perceived help accounted for unexplained variance in relationship quality. There were no differences between types of couples on levels of behaviors or on their contributions to relationship quality.

Physical activity levels of older community-dwelling adults are influenced by summer weather variables.

PubMed

Brandon, Caitlin A; Gill, Dawn P; Speechley, Mark; Gilliland, Jason; Jones, Gareth R

2009-04-01

Adequate daily physical activity (PA) is important for maintaining functional capacity and independence in older adults. However, most older adults in Canada do not engage in enough PA to sustain fitness and functional independence. Environmental influences, such as warmer daytime temperatures, may influence PA participation; however, few studies have examined the effect of summertime temperatures on PA levels in older adults. This investigation measured the influence of summertime weather variables on PA in 48 community-dwelling older adults who were randomly recruited from a local seniors' community centre. Each participant wore an accelerometer for a single 7-consecutive-day period (between 30 May and 9 August 2006) during waking hours, and completed a PA logbook to remark on major daily PA events. Local weather variables were collected from a national weather service and compared with PA counts per minute. Regression analysis revealed a curvilinear relationship between log-transformed PA and mean daily temperature (r2 = 0.025; p < 0.05). Linear mixed effects models that accounted for repeated measures nested within individuals were performed for monthly periods, meteorological variables, sex, age, and estimated maximal oxygen consumption, with PA as the dependent variable. Age and Air Quality Index remained significant variables within the model. Higher fitness levels had no effect on allowing individuals to perform more vigorous PA in warmer temperatures.

Interactions between neighborhood characteristics and individual functional status in relation to disability among Québec urbanites.

PubMed

Philibert, Mathieu D; Pampalon, Robert; Hamel, Denis; Daniel, Mark

2013-10-01

Disability is conceived as a person-context interaction. Neighborhoods are among the contexts potentially influencing disability. It is thus expected that neighborhood characteristics will be associated with disability prevalence and that such associations will be moderated by individual-level functional status. Empirical research targeting the influences of features of urban environments is relatively rare. To evaluate the presence of contextual differences in disability prevalence and to assess the moderating role of individual functional status on the association between neighborhood characteristics and disability prevalence. Multi-level analyses of individual-level data obtained from the Canadian Community Health Survey and neighborhood-level data derived from the Canada census. A contextual component was observed in the variability of disability prevalence. Significant neighborhood-level differences in disability were found across levels of social deprivation. Evidence of person-place interaction was equivocal. The contextual component of the variability in disability prevalence offers potential for targeting interventions to neighborhoods. The pathway by which social structure is associated with disability prevalence requires further research. Analyses of particular functional limitations may enhance our understanding of the mechanisms by which socioenvironmental factors affect disability. Publicly available survey data on disability in the general Canadian population, while useful, has limitations with respect to estimating socioenvironmental correlates of disability and potential person-place interactions. Copyright © 2013 Elsevier Inc. All rights reserved.

Predictors of early survival in Soay sheep: cohort-, maternal- and individual-level variation

PubMed Central

Jones, Owen R; Crawley, Michael J; Pilkington, Jill G; Pemberton, Josephine M

2005-01-01

A demographic understanding of population dynamics requires an appreciation of the processes influencing survival—a demographic rate influenced by parameters varying at the individual, maternal and cohort level. There have been few attempts to partition the variance in demography contributed by each of these parameter types. Here, we use data from a feral population of Soay sheep (Ovis aries), from the island of St Kilda, to explore the relative importance of these parameter types on early survival. We demonstrate that the importance of variation occurring at the level of the individual, and maternally, far outweighs that occurring at the cohort level. The most important variables within the individual and maternal levels were birth weight and maternal age class, respectively. This work underlines the importance of using individual based models in ecological demography and we, therefore, caution against studies that focus solely on population processes. PMID:16321784

The validity of the Gait Variability Index for individuals with mild to moderate Parkinson's disease.

PubMed

Rennie, Linda; Dietrichs, Espen; Moe-Nilssen, Rolf; Opheim, Arve; Franzén, Erika

2017-05-01

Increased step-to-step variability is a feature of gait in individuals with Parkinson's disease (PD) and is associated with increased disease severity and reductions in balance and mobility. The Gait Variability Index (GVI) quantifies gait variability in spatiotemporal variables where a score ≥100 indicates a similar level of gait variability as the control group, and lower scores denote increased gait variability. The study aim was to explore mean GVI score and investigate construct validity of the index for individuals with mild to moderate PD. 100 (57 males) subjects with idiopathic PD, Hoehn & Yahr 2 (n=44) and 3, and ≥60 years were included. Data on disease severity, dynamic balance, mobility and spatiotemporal gait parameters at self-selected speed (GAITRite) was collected. The results showed a mean overall GVI: 97.5 (SD 11.7) and mean GVI for the most affected side: 94.5 (SD 10.6). The associations between the GVI and Mini- BESTest and TUG were low (r=0.33 and 0.42) and the GVI could not distinguish between Hoehn & Yahr 2 and 3 (AUC=0.529, SE=0.058, p=0.622). The mean GVI was similar to previously reported values for older adults, contrary to consistent reports of increased gait variability in PD compared to healthy peers. Therefore, the validity of the GVI could not be confirmed for individuals with mild to moderate PD in its current form due to low associations with validated tests for functional balance and mobility and poor discriminatory ability. Future work should aim to establish which spatiotemporal variables are most informative regarding gait variability in individuals with PD. Copyright © 2017 Elsevier B.V. All rights reserved.

Catch me if I fall! Enacted uncertainty avoidance and the social safety net as country-level moderators in the job insecurity-job attitudes link.

PubMed

Debus, Maike E; Probst, Tahira M; König, Cornelius J; Kleinmann, Martin

2012-05-01

Job insecurity is related to many detrimental outcomes, with reduced job satisfaction and affective organizational commitment being the 2 most prominent reactions. Yet, effect sizes vary greatly, suggesting the presence of moderator variables. On the basis of Lazarus's cognitive appraisal theory, we assumed that country-level enacted uncertainty avoidance and a country's social safety net would affect an individual's appraisal of job insecurity. More specifically, we hypothesized that these 2 country-level variables would buffer the negative relationships between job insecurity and the 2 aforementioned job attitudes. Combining 3 different data sources, we tested the hypotheses in a sample of 15,200 employees from 24 countries by applying multilevel modeling. The results confirmed the hypotheses that both enacted uncertainty avoidance and the social safety net act as cross-level buffer variables. Furthermore, our data revealed that the 2 cross-level interactions share variance in explaining the 2 job attitudes. Our study responds to calls to look at stress processes from a multilevel perspective and highlights the potential importance of governmental regulation when it comes to individual stress processes. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

Variable ecological conditions promote male helping by changing banded mongoose group composition

PubMed Central

Sanderson, Jennifer L.; Mwanghuya, Francis; Businge, Robert; Kyabulima, Solomon; Hares, Michelle C.; Inzani, Emma; Kalema-Zikusoka, Gladys; Mwesige, Kenneth; Thompson, Faye J.; Vitikainen, Emma I. K.; Cant, Michael A.

2016-01-01

Ecological conditions are expected to have an important influence on individuals’ investment in cooperative care. However, the nature of their effects is unclear: both favorable and unfavorable conditions have been found to promote helping behavior. Recent studies provide a possible explanation for these conflicting results by suggesting that increased ecological variability, rather than changes in mean conditions, promote cooperative care. However, no study has tested whether increased ecological variability promotes individual-level helping behavior or the mechanisms involved. We test this hypothesis in a long-term study population of the cooperatively breeding banded mongoose, Mungos mungo, using 14 years of behavioral and meteorological data to explore how the mean and variability of ecological conditions influence individual behavior, body condition, and survival. Female body condition was more sensitive to changes in rainfall leading to poorer female survival and pronounced male-biased group compositions after periods of high rainfall variability. After such periods, older males invested more in helping behavior, potentially because they had fewer mating opportunities. These results provide the first empirical evidence for increased individual helping effort in more variable ecological conditions and suggest this arises because of individual differences in the effect of ecological conditions on body condition and survival, and the knock-on effect on social group composition. Individual differences in sensitivity to environmental variability, and the impacts this has on the internal structure and composition of animal groups, can exert a strong influence on the evolution and maintenance of social behaviors, such as cooperative care. PMID:27418750

Effects of EFL Individual Learner Variables on Foreign Language Reading Anxiety and Metacognitive Reading Strategy Use.

PubMed

Lien, Hsin-Yi

2016-08-01

Past research has shown an association between foreign language reading anxiety and reading strategy. However, individual variables tend to affect foreign language anxiety and strategy use. The present study examined a hypothesized model that specified direct and indirect effects among English and foreign languages readers' distinct variables, including academic level; self-perceived English level; and satisfaction with reading proficiency, reading anxiety, and metacognitive awareness of reading strategies. A total of 523 volunteer Taiwanese college students provided 372 valid responses to a written questionnaire (281 women and 91 men; M age = 19.7 years, SD = 1.1) containing the translated versions of Foreign Language Reading Anxiety Scale, Survey of Reading Strategies Inventory, and self-assessment background questionnaire. The results showed that self-evaluation of reading proficiency did not correlate with academic level and readers' perceptions. Satisfaction had a direct effect on foreign language reading anxiety but not on metacognitive awareness of reading strategies. Results of path analysis demonstrated that the perception learners who had their own reading proficiency predicted their foreign language reading anxiety and was a mediating variable for metacognitive reading strategy use. © The Author(s) 2016.

Aging and death-associated changes in serum albumin variability over the course of chronic hemodialysis treatment.

PubMed

Nakazato, Yuichi; Kurane, Riichi; Hirose, Satoru; Watanabe, Akihisa; Shimoyama, Hiromi

2017-01-01

Several epidemiological studies have demonstrated associations between variability in a number of biological parameters and adverse outcomes. As the variability may reflect impaired homeostatic regulation, we assessed albumin variability over time in chronic hemodialysis (HD) patients. Data from 1346 subjects who received chronic HD treatment from May 2001 to February 2015 were analyzed according to three phases of HD treatment: post-HD initiation, during maintenance HD treatment, and before death. The serum albumin values were grouped according to the time interval from HD initiation or death, and the yearly trends for both the albumin levels and the intra-individual albumin variability (quantified by the residual coefficient of variation: Alb-rCV) were examined. The HD initiation and death-associated changes were also analyzed using generalized additive mixed models. Furthermore, the long-term trend throughout the maintenance treatment period was evaluated separately using linear regression models. Albumin levels and variability showed distinctive changes during each of the 3 periods. After HD initiation, albumin variability decreased and reached a nadir within a year. During the subsequent maintenance treatment period (interquartile range = 5.2-11.0 years), the log Alb-rCV showed a significant upward trend (mean slope: 0.011 ± 0.035 /year), and its overall mean was -1.49 ± 0.08 (equivalent to an Alb-rCV of 3.22%). During the 1-2 years before death, this upward trend clearly accelerated, and the mean log Alb-rCV in the last year of life was -1.36 ± 0.17. The albumin levels and variability were negatively correlated with each other and exhibited exactly opposite movements throughout the course of chronic HD treatment. Different from the albumin levels, albumin variability was not dependent on chronological age but was independently associated with an individual's aging and death process. The observed upward trend in albumin variability seems to be consistent with a presumed aging-related decline in homeostatic capacity.

Suggestion of new possibilities in approaching individual variability in appetite through constitutional typology: a pilot study

PubMed Central

2012-01-01

Background Appetite is intricately connected to eating behaviors and shows a high individual variability. In an attempt to approach the problem of gut hormone profiles, appetite, and eating behaviors at the individual level, we have adopted a constitutional typing system widely used in traditional East-Asian medicine, the Sasang constitutional typology, in order to determine the individual variations in appetite, eating behavior, and weight change. Methods This pilot study was designed to investigate the variability of appetite among individuals by tracking the gut hormone patterns across different constitutional types. Pre- and post-prandial concentrations of anorectic (peptide YY (PYY), glucagon-like peptide 1 (GLP-1)) and orexigenic (active ghrelin) gut hormones were measured in healthy, normal-weight (18.5 kg/m2 ≤BMI <23 kg/m2) male subjects aged 20–35 (Soyang (SY) (n = 9), Taeeum (TE) (n = 9), and Soeum (SE) (n = 10) constitutional types). Results Significant differences were found only in the PYY concentrations across the three groups (p = 0.031). The PYY concentration peaked at 30-min post-prandial in the SE group and was significantly higher compared to the other two groups (p = 0.004). The GLP-1 concentration peaked at 15-min post-prandial in the SE group (not significant). The ghrelin levels at 30-min pre-prandial were relatively lower in the TE group compared to the other groups (not significant). Conclusions In conclusion, although with weak statistical power, meaningful gut hormone patterns specific to each constitutional type were discovered in this pilot study, which could offer a new method of approaching the problem of appetite and eating behavior from the angle of individual variability in appetite. PMID:22889232

On the value of aiming high: the causes and consequences of ambition.

PubMed

Judge, Timothy A; Kammeyer-Mueller, John D

2012-07-01

Ambition is a commonly mentioned but poorly understood concept in social science research. We sought to contribute to understanding of the concept by developing and testing a model in which ambition is a middle-level trait (Cantor, 1990)-predicted by more distal characteristics but, due to its teleological nature, more proximally situated to predict career success. A 7-decade longitudinal sample of 717 high-ability individuals from the Terman life-cycle study (Terman, Sears, Cronbach, & Sears, 1989) was used in the current study. Results indicated that ambition was predicted by individual differences-conscientiousness, extraversion, neuroticism, and general mental ability-and a socioeconomic background variable: parents' occupational prestige. Ambition, in turn, was positively related to educational attainment, occupation prestige, and income. Ambition had significant total effects with all of the endogenous variables except mortality. Overall, the results support the thesis that ambition is a middle-level trait-related to but distinct from more distal individual difference variables-that has meaningful effects on career success. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

You are what you eat: diet shapes body composition, personality and behavioural stability.

PubMed

Han, Chang S; Dingemanse, Niels J

2017-01-10

Behavioural phenotypes vary within and among individuals. While early-life experiences have repeatedly been proposed to underpin interactions between these two hierarchical levels, the environmental factors causing such effects remain under-studied. We tested whether an individual's diet affected both its body composition, average behaviour (thereby causing among-individual variation or 'personality') and within-individual variability in behaviour and body weight (thereby causing among-individual differences in residual within-individual variance or 'stability'), using the Southern field cricket Gryllus bimaculatus as a model. We further asked whether effects of diet on the expression of these variance components were sex-specific. Manipulating both juvenile and adult diet in a full factorial design, individuals were put, in each life-stage, on a diet that was either relatively high in carbohydrates or relatively high in protein. We subsequently measured the expression of multiple behavioural (exploration, aggression and mating activity) and morphological traits (body weight and lipid mass) during adulthood. Dietary history affected both average phenotype and level of within-individual variability: males raised as juveniles on high-protein diets were heavier, more aggressive, more active during mating, and behaviourally less stable, than conspecifics raised on high-carbohydrate diets. Females preferred more protein in their diet compared to males, and dietary history affected average phenotype and within-individual variability in a sex-specific manner: individuals raised on high-protein diets were behaviourally less stable in their aggressiveness but this effect was only present in males. Diet also influenced individual differences in male body weight, but within-individual variance in female body weight. This study thereby provides experimental evidence that dietary history explains both heterogeneous residual within-individual variance (i.e., individual variation in 'behavioural stability') and individual differences in average behaviour (i.e., 'personality'), though dietary effects were notably trait-specific. These findings call for future studies integrating proximate and ultimate perspectives on the role of diet in the evolution of repeatedly expressed traits, such as behaviour and body weight.

Are Changes in Neighbourhood Perceptions Associated with Changes in Self-Rated Mental Health in Adults? A 13-Year Repeat Cross-Sectional Study, UK.

PubMed

Olsen, Jonathan R; Dundas, Ruth; Ellaway, Anne

2017-11-29

The aim of this study was to examine changes in neighbourhood perceptions on self-rated mental health problems over time, and to explore demographic, geographic and socio-economic factors as determinants of increased or decreased anxiety and depression symptoms. We conducted a repeat cross-sectional study of individuals (N: 4480) living in the same areas of west central Scotland in 1997 and 2010. Individuals were asked to complete a questionnaire at both time-points, containing 14 questions relating to neighbourhood perceptions and the Hospital Anxiety and Depression Scale (HADS). A three-level linear regression model was fitted to HADS scores and changes in neighbourhood perceptions over time; controlling for a number of individual and area-level variables. Overall, area-level mean HADS scores decreased from 1997 to 2010. When adjusted for individual and area-level variables, this decrease did not remain for HADS anxiety. Applying an overall 14-scale neighbourhood perception measure, worsening neighbourhood perceptions were associated with small increases in depression (0.04, 95% confidence interval (CI) 0.01 to 0.07) and anxiety (0.04, 95% CI 0.00 to 0.08) scores over time. This highlights a need for local and national policy to target areas where neighbourhood characteristics are substantially deteriorating in order to ensure the mental health of individuals does not worsen.

Are Changes in Neighbourhood Perceptions Associated with Changes in Self-Rated Mental Health in Adults? A 13-Year Repeat Cross-Sectional Study, UK

PubMed Central

Ellaway, Anne

2017-01-01

The aim of this study was to examine changes in neighbourhood perceptions on self-rated mental health problems over time, and to explore demographic, geographic and socio-economic factors as determinants of increased or decreased anxiety and depression symptoms. We conducted a repeat cross-sectional study of individuals (N: 4480) living in the same areas of west central Scotland in 1997 and 2010. Individuals were asked to complete a questionnaire at both time-points, containing 14 questions relating to neighbourhood perceptions and the Hospital Anxiety and Depression Scale (HADS). A three-level linear regression model was fitted to HADS scores and changes in neighbourhood perceptions over time; controlling for a number of individual and area-level variables. Overall, area-level mean HADS scores decreased from 1997 to 2010. When adjusted for individual and area-level variables, this decrease did not remain for HADS anxiety. Applying an overall 14-scale neighbourhood perception measure, worsening neighbourhood perceptions were associated with small increases in depression (0.04, 95% confidence interval (CI) 0.01 to 0.07) and anxiety (0.04, 95% CI 0.00 to 0.08) scores over time. This highlights a need for local and national policy to target areas where neighbourhood characteristics are substantially deteriorating in order to ensure the mental health of individuals does not worsen. PMID:29186035

Individual and neighbourhood determinants of social participation and social capital: a multilevel analysis of the city of Malmö, Sweden.

PubMed

Lindström, Martin; Merlo, Juan; Ostergren, Per-Olof

2002-06-01

The aim of this study was to analyse the impact of neighbourhood on individual social capital (measured as social participation). The study population consisted of 14,390 individuals aged 45-73 that participated in the Malmö diet and cancer study in 1992-1994, residing in 90 neighbourhoods of Malmö, Sweden (population 250,000). A multilevel logistic regression model, with individuals at the first level and neighbourhoods at the second level, was performed. The study analysed the effect (intra-area correlation and cross-level modification) of the neighbourhood on individual social capital after adjustment for compositional factors (e.g. age, sex, educational level, occupational status, disability pension, living alone, sick leave, unemployment) and, finally, one contextual migration factor. The prevalence of low social participation varied from 23.0% to 39.7% in the first and third neighbourhood quartiles, respectively. Neighbourhood factors accounted for 6.3% of the total variance in social participation, and this effect was reduced but not eliminated when adjusting for all studied variables (-73%), especially the occupational composition of the neighbourhoods (-58%). The contextual migration variable further reduced the variance in social participation at the neighbourhood level to some extent. Our study supports Putnam's notion that social capital, which is suggested to be an important factor for population health and possibly for health equity, is an aspect that is partly contextual in its nature.

A survey of variable selection methods in two Chinese epidemiology journals

PubMed Central

2010-01-01

Background Although much has been written on developing better procedures for variable selection, there is little research on how it is practiced in actual studies. This review surveys the variable selection methods reported in two high-ranking Chinese epidemiology journals. Methods Articles published in 2004, 2006, and 2008 in the Chinese Journal of Epidemiology and the Chinese Journal of Preventive Medicine were reviewed. Five categories of methods were identified whereby variables were selected using: A - bivariate analyses; B - multivariable analysis; e.g. stepwise or individual significance testing of model coefficients; C - first bivariate analyses, followed by multivariable analysis; D - bivariate analyses or multivariable analysis; and E - other criteria like prior knowledge or personal judgment. Results Among the 287 articles that reported using variable selection methods, 6%, 26%, 30%, 21%, and 17% were in categories A through E, respectively. One hundred sixty-three studies selected variables using bivariate analyses, 80% (130/163) via multiple significance testing at the 5% alpha-level. Of the 219 multivariable analyses, 97 (44%) used stepwise procedures, 89 (41%) tested individual regression coefficients, but 33 (15%) did not mention how variables were selected. Sixty percent (58/97) of the stepwise routines also did not specify the algorithm and/or significance levels. Conclusions The variable selection methods reported in the two journals were limited in variety, and details were often missing. Many studies still relied on problematic techniques like stepwise procedures and/or multiple testing of bivariate associations at the 0.05 alpha-level. These deficiencies should be rectified to safeguard the scientific validity of articles published in Chinese epidemiology journals. PMID:20920252

Posttraumatic stress disorder and community collective efficacy following the 2004 Florida hurricanes.

PubMed

Ursano, Robert J; McKibben, Jodi B A; Reissman, Dori B; Liu, Xian; Wang, Leming; Sampson, Robert J; Fullerton, Carol S

2014-01-01

There is a paucity of research investigating the relationship of community-level characteristics such as collective efficacy and posttraumatic stress following disasters. We examine the association of collective efficacy with probable posttraumatic stress disorder and posttraumatic stress disorder symptom severity in Florida public health workers (n = 2249) exposed to the 2004 hurricane season using a multilevel approach. Anonymous questionnaires were distributed electronically to all Florida Department of Health personnel nine months after the 2004 hurricane season. The collected data were used to assess posttraumatic stress disorder and collective efficacy measured at both the individual and zip code levels. The majority of participants were female (80.42%), and ages ranged from 20 to 78 years (median = 49 years); 73.91% were European American, 13.25% were African American, and 8.65% were Hispanic. Using multi-level analysis, our data indicate that higher community-level and individual-level collective efficacy were associated with a lower likelihood of having posttraumatic stress disorder (OR = 0.93, CI = 0.88-0.98; and OR = 0.94, CI = 0.92-0.97, respectively), even after adjusting for individual sociodemographic variables, community socioeconomic characteristic variables, individual injury/damage, and community storm damage. Higher levels of community-level collective efficacy and individual-level collective efficacy were also associated with significantly lower posttraumatic stress disorder symptom severity (b = -0.22, p<0.01; and b = -0.17, p<0.01, respectively), after adjusting for the same covariates. Lower rates of posttraumatic stress disorder are associated with communities with higher collective efficacy. Programs enhancing community collective efficacy may be an important part of prevention practices and possibly lead to a reduction in the rate of posttraumatic stress disorder post-disaster.

Transdermal scopolamine in the prevention of motion sickness - Evaluation of the time course of efficacy

NASA Technical Reports Server (NTRS)

Homick, J. L.; Reschke, M. F.; Degioanni, J.; Cintron-Trevino, N. M.; Kohl, R. L.

1983-01-01

This study evaluated the time course of efficacy of transdermal scopolamine in the prevention of motion sickness induced by exposure to coriolis stimulation in a rotating chair. We measured levels of efficacy, quantified side effects and symptoms, and determined inter- and intra-subject variability following use of transdermal scopolamine. The response to transdermal scopolamine was highly variable, although overall we recorded a 40 percent improvement in test scores 16-72 h after application of the transdermal system. This variability could not be explained solely by the levels of scopolamine present in the blood. The improvement was not due to the artifactual repression by scopolamine of selected symptoms of motion sickness. An unexpectedly high incidence of side effects was reported. It was concluded that the therapeutic use of transdermal scopolamine be evaluated individually and that individuals be cautioned that subsequent usage may not always be effective.

Clarifying the Use of Aggregated Exposures in Multilevel Models: Self-Included vs. Self-Excluded Measures

PubMed Central

Suzuki, Etsuji; Yamamoto, Eiji; Takao, Soshi; Kawachi, Ichiro; Subramanian, S. V.

2012-01-01

Background Multilevel analyses are ideally suited to assess the effects of ecological (higher level) and individual (lower level) exposure variables simultaneously. In applying such analyses to measures of ecologies in epidemiological studies, individual variables are usually aggregated into the higher level unit. Typically, the aggregated measure includes responses of every individual belonging to that group (i.e. it constitutes a self-included measure). More recently, researchers have developed an aggregate measure which excludes the response of the individual to whom the aggregate measure is linked (i.e. a self-excluded measure). In this study, we clarify the substantive and technical properties of these two measures when they are used as exposures in multilevel models. Methods Although the differences between the two aggregated measures are mathematically subtle, distinguishing between them is important in terms of the specific scientific questions to be addressed. We then show how these measures can be used in two distinct types of multilevel models—self-included model and self-excluded model—and interpret the parameters in each model by imposing hypothetical interventions. The concept is tested on empirical data of workplace social capital and employees' systolic blood pressure. Results Researchers assume group-level interventions when using a self-included model, and individual-level interventions when using a self-excluded model. Analytical re-parameterizations of these two models highlight their differences in parameter interpretation. Cluster-mean centered self-included models enable researchers to decompose the collective effect into its within- and between-group components. The benefit of cluster-mean centering procedure is further discussed in terms of hypothetical interventions. Conclusions When investigating the potential roles of aggregated variables, researchers should carefully explore which type of model—self-included or self-excluded—is suitable for a given situation, particularly when group sizes are relatively small. PMID:23251609

Epigenetic Variability in the Genetically Uniform Forest Tree Species Pinus pinea L

PubMed Central

Sáez-Laguna, Enrique; Guevara, María-Ángeles; Díaz, Luis-Manuel; Sánchez-Gómez, David; Collada, Carmen; Aranda, Ismael; Cervera, María-Teresa

2014-01-01

There is an increasing interest in understanding the role of epigenetic variability in forest species and how it may contribute to their rapid adaptation to changing environments. In this study we have conducted a genome-wide analysis of cytosine methylation pattern in Pinus pinea, a species characterized by very low levels of genetic variation and a remarkable degree of phenotypic plasticity. DNA methylation profiles of different vegetatively propagated trees from representative natural Spanish populations of P. pinea were analyzed with the Methylation Sensitive Amplified Polymorphism (MSAP) technique. A high degree of cytosine methylation was detected (64.36% of all scored DNA fragments). Furthermore, high levels of epigenetic variation were observed among the studied individuals. This high epigenetic variation found in P. pinea contrasted with the lack of genetic variation based on Amplified Fragment Length Polymorphism (AFLP) data. In this manner, variable epigenetic markers clearly discriminate individuals and differentiates two well represented populations while the lack of genetic variation revealed with the AFLP markers fail to differentiate at both, individual or population levels. In addition, the use of different replicated trees allowed identifying common polymorphic methylation sensitive MSAP markers among replicates of a given propagated tree. This set of MSAPs allowed discrimination of the 70% of the analyzed trees. PMID:25084460

Epigenetic variability in the genetically uniform forest tree species Pinus pinea L.

PubMed

Sáez-Laguna, Enrique; Guevara, María-Ángeles; Díaz, Luis-Manuel; Sánchez-Gómez, David; Collada, Carmen; Aranda, Ismael; Cervera, María-Teresa

2014-01-01

There is an increasing interest in understanding the role of epigenetic variability in forest species and how it may contribute to their rapid adaptation to changing environments. In this study we have conducted a genome-wide analysis of cytosine methylation pattern in Pinus pinea, a species characterized by very low levels of genetic variation and a remarkable degree of phenotypic plasticity. DNA methylation profiles of different vegetatively propagated trees from representative natural Spanish populations of P. pinea were analyzed with the Methylation Sensitive Amplified Polymorphism (MSAP) technique. A high degree of cytosine methylation was detected (64.36% of all scored DNA fragments). Furthermore, high levels of epigenetic variation were observed among the studied individuals. This high epigenetic variation found in P. pinea contrasted with the lack of genetic variation based on Amplified Fragment Length Polymorphism (AFLP) data. In this manner, variable epigenetic markers clearly discriminate individuals and differentiates two well represented populations while the lack of genetic variation revealed with the AFLP markers fail to differentiate at both, individual or population levels. In addition, the use of different replicated trees allowed identifying common polymorphic methylation sensitive MSAP markers among replicates of a given propagated tree. This set of MSAPs allowed discrimination of the 70% of the analyzed trees.

Understanding Recession and Self-Rated Health with the Partial Proportional Odds Model: An Analysis of 26 Countries.

PubMed

Mayer, Adam; Foster, Michelle

2015-01-01

Self-rated health is demonstrated to vary substantially by both personal socio-economic status and national economic conditions. However, studies investigating the combined influence of individual and country level economic indicators across several countries in the context of recent global recession are limited. This paper furthers our knowledge of the effect of recession on health at both the individual and national level. Using the Life in Transition II study, which provides data from 19,759 individuals across 26 European nations, we examine the relationship between self-rated health, personal economic experiences, and macro-economic change. Data analyses include, but are not limited to, the partial proportional odds model which permits the effect of predictors to vary across different levels of our dependent variable. Household experiences with recession, especially a loss of staple good consumption, are associated with lower self-rated health. Most individual-level experiences with recession, such as a job loss, have relatively small negative effects on perceived health; the effect of individual or household economic hardship is strongest in high income nations. Our findings also suggest that macroeconomic growth improves self-rated health in low-income nations but has no effect in high-income nations. Individuals with the greatest probability of "good" self-rated health reside in wealthy countries ($23,910 to $50, 870 GNI per capita). Both individual and national economic variables are predictive of self-rated health. Personal and household experiences are most consequential for self-rated health in high income nations, while macroeconomic growth is most consequential in low-income nations.

Variability of individual genetic load: consequences for the detection of inbreeding depression.

PubMed

Restoux, Gwendal; Huot de Longchamp, Priscille; Fady, Bruno; Klein, Etienne K

2012-03-01

Inbreeding depression is a key factor affecting the persistence of natural populations, particularly when they are fragmented. In species with mixed mating systems, inbreeding depression can be estimated at the population level by regressing the average progeny fitness by the selfing rate of their mothers. We applied this method using simulated populations to investigate how population genetic parameters can affect the detection power of inbreeding depression. We simulated individual selfing rates and genetic loads from which we computed fitness values. The regression method yielded high statistical power, inbreeding depression being detected as significant (5 % level) in 92 % of the simulations. High individual variation in selfing rate and high mean genetic load led to better detection of inbreeding depression while high among-individual variation in genetic load made it more difficult to detect inbreeding depression. For a constant sampling effort, increasing the number of progenies while decreasing the number of individuals per progeny enhanced the detection power of inbreeding depression. We discuss the implication of among-mother variability of genetic load and selfing rate on inbreeding depression studies.

Predicting True Reading Gains After Remedial Tutoring.

ERIC Educational Resources Information Center

Dahlke, Anita B.

Using selected student variables, an attempt was made to predict retarded readers' true reading gains after remedial tutoring. The independent variables consisted of IQ and subtest scores obtained on the Wechsler Intelligence Scale for Children (WISC), pretutoring reading levels on the individually administered Diagnostic Reading Scales test, age,…

Explaining variability in first grazing season heifer growth combining individually measured parasitological and clinical indicators with exposure to gastrointestinal nematode infection based on grazing management practice.

PubMed

Merlin, Aurélie; Chauvin, Alain; Madouasse, Aurélien; Froger, Sébastien; Bareille, Nathalie; Chartier, Christophe

2016-07-30

The objective of our study was to explain the variability of average daily weight gain (ADWG) due to gastrointestinal nematode (GIN) infection for 291 non treated first grazing season (FGS) heifers, from 12 independent groups in the western part of France, by combining parasitological and clinical indicators at individual level and grazing management indicators at group level. Parasitological indicators were faecal egg count (FEC), anti Ostertagia ostertagi antibody level (Ostertagia ODR), and pepsinogen level. Clinical indicators were diarrhea score (DISCO) and breech soiling score (BSS). At group level, grazing management practice (GMP), based on three variables (supplementation, month of turnout, grazing season duration), was clustered into three categories reflecting low, medium or high exposure (EXP) to GIN. Depending on the groups, turnout was from mid-March to early July and housing was from mid-October to late November, with a FGS duration ranging from 4 to 8.4 months. At turnout, the mean age of heifers was 8 months (range: 6-16 months) and they weighed between 175 and 268kg. In each GMP category, FEC significantly decreased between the mid-season and the housing, while Ostertagia ODR and pepsinogen level increased gradually throughout the grazing season. In contrast, clinical indicators did not show any seasonal variation. In a multivariate linear model, 22% of the ADWG variability was significantly explained by two individual indicators (Ostertagia ODR: 12.6%, DISCO: 4.8%) and by the group indicator (GMP category: 4.8%). ADWG losses due to GIN exposure (Ostertagia ODR) were estimated up to 39kg per heifer for the overall grazing season. For groups within the low EXP category the difference between animals with low (<697g/day) or high (>697g/day) ADWG was explained by the clinical indicator DISCO. In contrast, for groups within the medium and high EXP categories this difference was explained by a parasitological indicator (Ostertagia ODR). This study highlighted the value of combining both grazing management (group level) and parasitological (individual level) indicators to assess the impact of GIN on ADWG of FGS heifers. As a result, this combination might allow a better discrimination of animals or groups that may be in need of treatment in a targeting selective treatment approach. Copyright © 2016 Elsevier B.V. All rights reserved.

Influence of neighbourhood purchasing power on breastfeeding at four months of age: a Swedish population-based cohort study

PubMed Central

2013-01-01

Background Parental socioeconomic status (SES) is an important determinant in child health, influencing beneficial factors such as breastfeeding. A better understanding of the influence of neighbourhood-level SES measures, relating to spatial determinants, might lead to targeted actions to promote breastfeeding during infancy. Methods A cross-sectional study analysis the association between breastfeeding at four months of age and neighbourhood purchasing power, taking account of individual-level variables including maternal age, smoking and parental level of education. Data were obtained from a prospective population- based cohort study recruited from birth in 2007–2008 in the Halland region, southwestern Sweden. Questionnaire data on the individual-level variables and the outcome variable of breastfeeding at four months (yes/no) were used (n = 2 407). Each mother was geo-coded with respect to her residential parish (there are 61 parishes in the region) and then stratified by parish-level household purchasing power. It emerged that four neighbourhood characteristics were reasonable to use, viz. <10%, 10-19%, 20-29% and ≥ 30% of the resident families with low purchasing power. Results The proportion of mothers not breastfeeding at four months of age showed a highly significant trend across the neighbourhood strata (p = 0.00004): from 16.3% (< 10% with low purchasing power) to 29.4% (≥ 30% with low purchasing power), yielding an OR of 2.24 (95% confidence interval: 1.45-3.16). After adjusting for the individual-level variables, the corresponding OR = 1.63 (1.07-2.56) was significant and the trend across the strata was still evident (p = 0.05). A multi-level analysis estimated that, in the neighbourhoods with ≥ 30% of the families with low purchasing power, 20% more mothers than expected, taking account of the individual-level factors, reported no breastfeeding at four months of age (≥ 95% posterior probability of an elevated observed-to-expected ratio). Conclusion The neighbourhood purchasing power provided a spatial determinant of low numbers of mothers breastfeeding at four months of age, which could be relevant to consider for targeted actions. The elevated observed-to-expected ratio in the neighbourhoods with the lowest purchasing power points toward a possible contextual influence. PMID:24237634

Combined and Relative Effect Levels of Perceived Risk, Knowledge, Optimism, Pessimism, and Social Trust on Anxiety among Inhabitants Concerning Living on Heavy Metal Contaminated Soil

PubMed Central

Tang, Zhongjun; Guo, Zengli; Zhou, Li; Xue, Shengguo; Zhu, Qinfeng; Zhu, Huike

2016-01-01

This research aims at combined and relative effect levels on anxiety of: (1) perceived risk, knowledge, optimism, pessimism, and social trust; and (2) four sub-variables of social trust among inhabitants concerning living on heavy metal contaminated soil. On the basis of survey data from 499 Chinese respondents, results suggest that perceived risk, pessimism, optimism, and social trust have individual, significant, and direct effects on anxiety, while knowledge does not. Knowledge has significant, combined, and interactive effects on anxiety together with social trust and pessimism, respectively, but does not with perceived risk and optimism. Social trust, perceived risk, pessimism, knowledge, and optimism have significantly combined effects on anxiety; the five variables as a whole have stronger predictive values than each one individually. Anxiety is influenced firstly by social trust and secondly by perceived risk, pessimism, knowledge, and optimism. Each of four sub-variables of social trust has an individual, significant, and negative effect on anxiety. When introducing four sub-variables into one model, trust in social organizations and in the government have significantly combined effects on anxiety, while trust in experts and in friends and relatives do not; anxiety is influenced firstly by trust in social organization, and secondly by trust in the government. PMID:27827866

Combined and Relative Effect Levels of Perceived Risk, Knowledge, Optimism, Pessimism, and Social Trust on Anxiety among Inhabitants Concerning Living on Heavy Metal Contaminated Soil.

PubMed

Tang, Zhongjun; Guo, Zengli; Zhou, Li; Xue, Shengguo; Zhu, Qinfeng; Zhu, Huike

2016-11-02

This research aims at combined and relative effect levels on anxiety of: (1) perceived risk, knowledge, optimism, pessimism, and social trust; and (2) four sub-variables of social trust among inhabitants concerning living on heavy metal contaminated soil. On the basis of survey data from 499 Chinese respondents, results suggest that perceived risk, pessimism, optimism, and social trust have individual, significant, and direct effects on anxiety, while knowledge does not. Knowledge has significant, combined, and interactive effects on anxiety together with social trust and pessimism, respectively, but does not with perceived risk and optimism. Social trust, perceived risk, pessimism, knowledge, and optimism have significantly combined effects on anxiety; the five variables as a whole have stronger predictive values than each one individually. Anxiety is influenced firstly by social trust and secondly by perceived risk, pessimism, knowledge, and optimism. Each of four sub-variables of social trust has an individual, significant, and negative effect on anxiety. When introducing four sub-variables into one model, trust in social organizations and in the government have significantly combined effects on anxiety, while trust in experts and in friends and relatives do not; anxiety is influenced firstly by trust in social organization, and secondly by trust in the government.

Predictors of Nightly Subjective-Objective Sleep Discrepancy in Poor Sleepers over a Seven-Day Period

PubMed Central

Herbert, Vanessa; Pratt, Daniel; Emsley, Richard; Kyle, Simon D.

2017-01-01

This study sought to examine predictors of subjective/objective sleep discrepancy in poor sleepers. Forty-two individuals with insomnia symptoms (mean age = 36.2 years, 81% female) were recruited to take part in a prospective study which combined seven days of actigraphy with daily assessment of sleep perceptions, self-reported arousal, sleep effort, and mood upon awakening. A high level of intra-individual variability in measures of sleep discrepancy was observed. Multilevel modelling revealed that higher levels of pre-sleep cognitive activity and lower mood upon awakening were significantly and independently predictive of the underestimation of total sleep time. Greater levels of sleep effort predicted overestimation of sleep onset latency. These results indicate that psychophysiological variables are related to subjective/objective sleep discrepancy and may be important therapeutic targets in the management of insomnia. PMID:28282912

A test of the resource security and the body mass index reference point hypotheses of body dissatisfaction amongst adolescents in eight countries.

PubMed

Mellor, David; Fuller-Tyszkiewicz, Matthew; McCabe, Marita P; Ricciardelli, Lina A; Skouteris, Helen; Mussap, Alexander J

2014-01-01

This study aimed to identify cultural-level variables that may influence the extent to which adolescents from different cultural groups are dissatisfied with their bodies. A sample of 1730 male and 2000 female adolescents from Australia, Fiji, Malaysia, Tonga, Tongans in New Zealand, China, Chile, and Greece completed measures of body satisfaction, and the sociocultural influences on body image and body change questionnaire, and self-reported height and weight. Country gross domestic product and national obesity were recorded using global databases. Prevalence of obesity/overweight and cultural endorsement of appearance standards explained variance in individual-level body dissatisfaction (BD) scores, even after controlling for the influence of individual differences in body mass index and internalization of appearance standards. Cultural-level variables may account for the development of adolescent BD.

Lower Hemoglobin Concentration Is Associated with Retinal Ischemia and the Severity of Diabetic Retinopathy in Type 2 Diabetes

PubMed Central

Traveset, Alicia; Rubinat, Esther; Ortega, Emilio; Alcubierre, Nuria; Vazquez, Beatriz; Hernández, Marta; Jurjo, Carmen; Espinet, Ramon; Ezpeleta, Juan Antonio; Mauricio, Didac

2016-01-01

Aims. To assess the association of blood oxygen-transport capacity variables with the prevalence of diabetic retinopathy (DR), retinal ischemia, and macular oedema in patients with type 2 diabetes mellitus (T2DM). Methods. Cross-sectional, case-control study (N = 312) with T2DM: 153 individuals with DR and 159 individuals with no DR. Participants were classified according to the severity of DR and the presence of retinal ischemia or macular oedema. Hematological variables were collected by standardized methods. Three logistic models were adjusted to ascertain the association between hematologic variables with the severity of DR and the presence of retinal ischemia or macular oedema. Results. Individuals with severe DR showed significantly lower hemoglobin, hematocrit, and erythrocyte levels compared with those with mild disease and in individuals with retinal ischemia and macular oedema compared with those without these disorders. Hemoglobin was the only factor that showed a significant inverse association with the severity of DR [beta-coefficient = −0.52, P value = 0.003] and retinal ischemia [beta-coefficient = −0.49, P value = 0.001]. Lower erythrocyte level showed a marginally significant association with macular oedema [beta-coefficient = −0.86, P value = 0.055]. Conclusions. In patients with DR, low blood oxygen-transport capacity was associated with more severe DR and the presence of retinal ischemia. Low hemoglobin levels may have a key role in the development and progression of DR. PMID:27200379

Lower Hemoglobin Concentration Is Associated with Retinal Ischemia and the Severity of Diabetic Retinopathy in Type 2 Diabetes.

PubMed

Traveset, Alicia; Rubinat, Esther; Ortega, Emilio; Alcubierre, Nuria; Vazquez, Beatriz; Hernández, Marta; Jurjo, Carmen; Espinet, Ramon; Ezpeleta, Juan Antonio; Mauricio, Didac

2016-01-01

Aims. To assess the association of blood oxygen-transport capacity variables with the prevalence of diabetic retinopathy (DR), retinal ischemia, and macular oedema in patients with type 2 diabetes mellitus (T2DM). Methods. Cross-sectional, case-control study (N = 312) with T2DM: 153 individuals with DR and 159 individuals with no DR. Participants were classified according to the severity of DR and the presence of retinal ischemia or macular oedema. Hematological variables were collected by standardized methods. Three logistic models were adjusted to ascertain the association between hematologic variables with the severity of DR and the presence of retinal ischemia or macular oedema. Results. Individuals with severe DR showed significantly lower hemoglobin, hematocrit, and erythrocyte levels compared with those with mild disease and in individuals with retinal ischemia and macular oedema compared with those without these disorders. Hemoglobin was the only factor that showed a significant inverse association with the severity of DR [beta-coefficient = -0.52, P value = 0.003] and retinal ischemia [beta-coefficient = -0.49, P value = 0.001]. Lower erythrocyte level showed a marginally significant association with macular oedema [beta-coefficient = -0.86, P value = 0.055]. Conclusions. In patients with DR, low blood oxygen-transport capacity was associated with more severe DR and the presence of retinal ischemia. Low hemoglobin levels may have a key role in the development and progression of DR.

Background Variables, Levels of Aggregation, and Standardized Test Scores

ERIC Educational Resources Information Center

Paulson, Sharon E.; Marchant, Gregory J.

2009-01-01

This article examines the role of student demographic characteristics in standardized achievement test scores at both the individual level and aggregated at the state, district, school levels. For several data sets, the majority of the variance among states, districts, and schools was related to demographic characteristics. Where these background…

Prediction of community mental health service utilization by individual and ecological level socio-economic factors.

PubMed

Donisi, Valeria; Tedeschi, Federico; Percudani, Mauro; Fiorillo, Andrea; Confalonieri, Linda; De Rosa, Corrado; Salazzari, Damiano; Tansella, Michele; Thornicroft, Graham; Amaddeo, Francesco

2013-10-30

Individuals with a more deprived socioeconomic status (SES) are more likely to have higher rates of psychiatric morbidity and use of psychiatric services. Such service use is also influenced by socioeconomic factors at the ecological level. The aim of this article is to investigate the influence of these variables on service utilization. All patients in contact with three Italian community psychiatric services (CPS) were included. Community and hospital contacts over 6 months were investigated. Socio-economic characteristics were described using a SES Index and two new Resources Accessibility Indexes. Low SES was found to be associated with more community service contacts. When other individual and ecological variables were controlled for, SES was negatively associated only with the number of home visits, which was about half the rate in deprived areas. An association between service utilization and the resources of the catchment area was also detected. The economic crisis in Europe is increasing inequality of access, so paying attention to SES characteristics at both the individual and the ecological levels is likely to become increasingly important in understanding patterns of psychiatric service utilization and planning care accordingly. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Implications of Supermarket Access, Neighborhood Walkability, and Poverty Rates for Diabetes Risk in an Employee Population

PubMed Central

Herrick, Cynthia J.; Yount, Byron W.; Eyler, Amy A.

2016-01-01

Objective Diabetes is a growing public health problem, and the environment in which people live and work may affect diabetes risk. The goal of this study was to examine the association between multiple aspects of environment and diabetes risk in an employee population. Design This was a retrospective cross-sectional analysis. Home environment variables were derived using employee zip code. Descriptive statistics were run on all individual and zip code level variables, stratified by diabetes risk and worksite. A multivariable logistic regression analysis was then conducted to determine the strongest associations with diabetes risk. Setting Data was collected from employee health fairs in a Midwestern health system 2009–2012. Subjects The dataset contains 25,227 unique individuals across four years of data. From this group, using an individual’s first entry into the database, 15,522 individuals had complete data for analysis. Results The prevalence of high diabetes risk in this population was 2.3%. There was significant variability in individual and zip code level variables across worksites. From the multivariable analysis, living in a zip code with higher percent poverty and higher walk score was positively associated with high diabetes risk, while living in a zip code with higher supermarket density was associated with a reduction in high diabetes risk. Conclusions Our study underscores the important relationship between poverty, home neighborhood environment, and diabetes risk, even in a relatively healthy employed population, and suggests a role for the employer in promoting health. PMID:26638995

Vocational outcome following spinal cord injury.

PubMed

Conroy, L; McKenna, K

1999-09-01

Non-experimental (ex post facto) survey research design involving the use of a fixed alternative format questionnaire. To investigate variables influencing vocational outcome, to identify barriers to gaining and sustaining employment and to identify the effects of variables on the type of work engaged in following spinal cord injury. The two sets of independent variables considered were, individual and injury-related factors (age at onset of injury, time since injury, extent/level of injury, highest educational qualification achieved pre-injury, and pre-injury occupation) and circumstantial factors (means of transport, access difficulties, perceived workplace discrimination, financial disincentives to work and perceived level of skill). The Princess Alexandra Hospital Spinal Injuries Unit, Queensland, Australia. Data on the variables and the vocational outcomes of having ever worked or studied post-injury, current employment status and post-injury occupation were obtained from survey responses. Demographical and medical data were gathered from medical records. Forward stepwise logistic regression revealed that having ever worked or studied post-injury was associated with all individual and injury-related factors except pre-injury occupation, and two circumstantial factors, namely means of transport and access difficulties. Current employment was associated with all circumstantial factors as well as age at injury and pre-injury occupation. Standard multiple regression analyses revealed that post-injury occupation was correlated with all individual and injury-related factors as well as means of transport and perceived workplace discrimination. Tailored rehabilitation programs for individuals with characteristics associated with less successful vocational outcomes may facilitate their employment status after injury.

Predator Persistence through Variability of Resource Productivity in Tritrophic Systems.

PubMed

Soudijn, Floor H; de Roos, André M

2017-12-01

The trophic structure of species communities depends on the energy transfer between trophic levels. Primary productivity varies strongly through time, challenging the persistence of species at higher trophic levels. Yet resource variability has mostly been studied in systems with only one or two trophic levels. We test the effect of variability in resource productivity in a tritrophic model system including a resource, a size-structured consumer, and a size-specific predator. The model complies with fundamental principles of mass conservation and the body-size dependence of individual-level energetics and predator-prey interactions. Surprisingly, we find that resource variability may promote predator persistence. The positive effect of variability on the predator arises through periods with starvation mortality of juvenile prey, which reduces the intraspecific competition in the prey population. With increasing variability in productivity and starvation mortality in the juvenile prey, the prey availability increases in the size range preferred by the predator. The positive effect of prey mortality on the trophic transfer efficiency depends on the biologically realistic consideration of body size-dependent and food-dependent functions for growth and reproduction in our model. Our findings show that variability may promote the trophic transfer efficiency, indicating that environmental variability may sustain species at higher trophic levels in natural ecosystems.

Inter-relationships between objective and subjective measures of the residential environment among urban African American women

PubMed Central

Sealy-Jefferson, Shawnita; Messer, Lynne; Slaughter-Acey, Jaime; Misra, Dawn P.

2016-01-01

Background The inter-relationships between objective (census-based) and subjective (resident reported) measures of the residential environment is understudied in African American (AA) populations. Methods Using data from the Life Influences on Fetal Environments Study (2009–2011) (n=1,387) of AA women, we quantified the area-level variation in subjective reports of residential healthy food availability, walkability, safety and disorder that can be accounted for with an objective neighborhood disadvantage index (NDI). Two-level generalized linear models estimated associations between objective and subjective measures of the residential environment, accounting for individual-level covariates. Results In unconditional models, intraclass correlation coefficients for block-group variance in subjective reports ranged from 11% (healthy food availability) to 30% (safety). Models accounting for the NDI (versus both NDI and individual level covariates) accounted for more variance in healthy food availability (23% versus 8%) and social disorder (40% versus 38%). The NDI and individual level variables accounted for 39% and 51% of the area-level variation in walkability and safety. Associations between subjective and objective measures of the residential environment were significant and in the expected direction. Conclusions Future studies on neighborhood effects on health, especially among AAs, should include a wide range of residential environment measures, including subjective, objective and spatial contextual variables. PMID:28160971

Does gender modify associations between self rated health and the social and economic characteristics of local environments?

PubMed

Kavanagh, Anne M; Bentley, Rebecca; Turrell, Gavin; Broom, Dorothy H; Subramanian, S V

2006-06-01

To examine whether area level socioeconomic disadvantage and social capital have different relations with women's and men's self rated health. The study used data from 15 112 respondents to the 1998 Tasmanian (Australia) healthy communities study (60% response rate) nested within 41 statistical local areas. Gender stratified analyses were conducted of the associations between the index of relative socioeconomic disadvantage (IRSD) and social capital (neighbourhood integration, neighbourhood alienation, neighbourhood safety, political participation, social trust, trust in institutions) and individual level self rated health using multilevel logistic regression analysis before (age only) and after adjustment for individual level confounders (marital status, indigenous status, income, education, occupation, smoking). The study also tested for interactions between gender and area level variables. IRSD was associated with poor self rated health for women (age adjusted p<0.001) and men (age adjusted p<0.001), however, the estimates attenuated when adjusted for individual level variables. Political participation and neighbourhood safety were protective for women's self rated health but not for men's. Interactions between gender and political participation (p = 0.010) and neighbourhood safety (p = 0.023) were significant. These finding suggest that women may benefit more than men from higher levels of area social capital.

Inter-relationships between objective and subjective measures of the residential environment among urban African American women.

PubMed

Sealy-Jefferson, Shawnita; Messer, Lynne; Slaughter-Acey, Jaime; Misra, Dawn P

2017-03-01

The inter-relationships between objective (census based) and subjective (resident reported) measures of the residential environment is understudied in African American (AA) populations. Using data from the Life Influences on Fetal Environments Study (2009-2011; n = 1387) of AA women, we quantified the area-level variation in subjective reports of residential healthy food availability, walkability, safety, and disorder that can be accounted for with an objective neighborhood disadvantage index (NDI). Two-level generalized linear models estimated associations between objective and subjective measures of the residential environment, accounting for individual-level covariates. In unconditional models, intraclass correlation coefficients for block-group variance in subjective reports ranged from 11% (healthy food availability) to 30% (safety). Models accounting for the NDI (vs. both NDI and individual-level covariates) accounted for more variance in healthy food availability (23% vs. 8%) and social disorder (40% vs. 38%). The NDI and individual-level variables accounted for 39% and 51% of the area-level variation in walkability and safety, respectively. Associations between subjective and objective measures of the residential environment were significant and in the expected direction. Future studies on neighborhood effects on health, especially among AAs, should include a wide range of residential environment measures, including subjective, objective, and spatial contextual variables. Copyright © 2016 Elsevier Inc. All rights reserved.

High variability of individual longitudinal motor performance over five years in very preterm infants.

PubMed

Janssen, Anjo J W M; Oostendorp, Rob A B; Akkermans, Reinier P; Steiner, Katerina; Kollée, Louis A A; Nijhuis-van der Sanden, Maria W G

2016-12-01

To determine longitudinal motor performance in very preterm (VPT) infants from 6 months to 5 years of age for the entire cohort of infants, according to gender and gestational age and at the individual level. Single-center, prospective longitudinal study of 201 VPT infants (106 boys) without severe impairments. Motor performance was assessed with the Bayley Scales of Infant Development (BSID-II-MS: 6, 12, 24 months) and the Movement Assessment Battery for Children (MABC-2-NL: 5 years). At 6, 12, and 24 months and then at 5 years, 77%, 80%, 48%, and 22% of the infants, respectively, showed delayed motor performance (<-1SD). At 5 years, girls performed significantly better than boys in manual dexterity and balance. MIXED MODEL ANALYSES: that examined interactions between time and gender and time and gestational age, revealed no significant interactions. The variance at child level was 29%. Linear mixed model analysis revealed that mean z-scores of -1.46 at 6 months of age declined significantly to -0.52 at 5 years. Individual longitudinal motor performance showed high variability. Longitudinal motor performance improved almost 1 SD over five years. However, the variability of individual longitudinal motor performance hampers evaluation in clinical care and research. Copyright © 2016 Elsevier Ltd. All rights reserved.

Estimating Individual Influences of Behavioral Intentions: An Application of Random-Effects Modeling to the Theory of Reasoned Action.

ERIC Educational Resources Information Center

Hedeker, Donald; And Others

1996-01-01

Methods are proposed and described for estimating the degree to which relations among variables vary at the individual level. As an example, M. Fishbein and I. Ajzen's theory of reasoned action is examined. This article illustrates the use of empirical Bayes methods based on a random-effects regression model to estimate individual influences…

To pair or not to pair: Sources of social variability with white-faced saki monkeys (Pithecia pithecia) as a case study.

PubMed

Thompson, Cynthia L

2016-05-01

Intraspecific variability in social systems is gaining increased recognition in primatology. Many primate species display variability in pair-living social organizations through incorporating extra adults into the group. While numerous models exist to explain primate pair-living, our tools to assess how and why variation in this trait occurs are currently limited. Here I outline an approach which: (i) utilizes conceptual models to identify the selective forces driving pair-living; (ii) outlines novel possible causes for variability in social organization; and (iii) conducts a holistic species-level analysis of social behavior to determine the factors contributing to variation in pair-living. A case study on white-faced sakis (Pithecia pithecia) is used to exemplify this approach. This species lives in either male-female pairs or groups incorporating "extra" adult males and/or females. Various conceptual models of pair-living suggest that high same-sex aggression toward extra-group individuals is a key component of the white-faced saki social system. Variable pair-living in white-faced sakis likely represents alternative strategies to achieve competency in this competition, in which animals experience conflicting selection pressures between achieving successful group defense and maintaining sole reproductive access to mates. Additionally, independent decisions by individuals may generate social variation by preventing other animals from adopting a social organization that maximizes fitness. White-faced saki inter-individual relationships and demographic patterns also lend conciliatory support to this conclusion. By utilizing both model-level and species-level approaches, with a consideration for potential sources of variation, researchers can gain insight into the factors generating variation in pair-living social organizations. © 2014 The Authors. American Journal of Primatology published by Wiley Periodicals, Inc.

A map of human microRNA variation uncovers unexpectedly high levels of variability

PubMed Central

2012-01-01

Background MicroRNAs (miRNAs) are key components of the gene regulatory network in many species. During the past few years, these regulatory elements have been shown to be involved in an increasing number and range of diseases. Consequently, the compilation of a comprehensive map of natural variability in a healthy population seems an obvious requirement for future research on miRNA-related pathologies. Methods Data on 14 populations from the 1000 Genomes Project were analyzed, along with new data extracted from 60 exomes of healthy individuals from a population from southern Spain, sequenced in the context of the Medical Genome Project, to derive an accurate map of miRNA variability. Results Despite the common belief that miRNAs are highly conserved elements, analysis of the sequences of the 1,152 individuals indicated that the observed level of variability is double what was expected. A total of 527 variants were found. Among these, 45 variants affected the recognition region of the corresponding miRNA and were found in 43 different miRNAs, 26 of which are known to be involved in 57 diseases. Different parts of the mature structure of the miRNA were affected to different degrees by variants, which suggests the existence of a selective pressure related to the relative functional impact of the change. Moreover, 41 variants showed a significant deviation from the Hardy-Weinberg equilibrium, which supports the existence of a selective process against some alleles. The average number of variants per individual in miRNAs was 28. Conclusions Despite an expectation that miRNAs would be highly conserved genomic elements, our study reports a level of variability comparable to that observed for coding genes. PMID:22906193

Exploring individual adaptations to an anterior cruciate ligament injury prevention programme.

PubMed

Fox, Aaron S; Bonacci, Jason; McLean, Scott G; Saunders, Natalie

2018-01-01

Individual responses to anterior cruciate ligament injury prevention programmes (ACL IPPs) have received little attention. This study examined the effects of an ACL IPP on neuromuscular control and lower limb biomechanics during landing at the group and individual levels. Sixteen female athletes were randomly allocated to training (n=8) or control (n=8) groups. Electromyography, and three-dimensional kinematic and kinetic data were collected during landing at two testing sessions. Repeated measures ANOVA and effect sizes (Cohen's d) examined the effect of the IPP at the group and individual levels. A sub-group analysis comparing the effect of the IPP on 'high-' (i.e. large peak knee abduction moment at baseline) versus 'low-risk' individuals was also conducted. At the group level; the IPP increased activation of the medial hamstrings prior to landing (p<0.001; d=0.264) and the medial gastrocnemius at landing (p<0.001; d=0.426), and increased hip external rotation early after initial contact (p<0.001; d=0.476). Variable adaptations were seen across individuals within the training group for all variables (p<0.001). The IPP had a large effect in reducing frontal plane knee moments for 'high-risk' individuals (d>0.91), however these results did not reach statistical significance (p>0.05). The IPP induced adaptations during landing, however, individual data revealed dissimilar responses to the programme. Individuals displaying a pre-existing high-risk strategy may incur greater benefits from IPPs, yet only if the programme targets the relevant high-risk strategy. Copyright © 2017 Elsevier B.V. All rights reserved.

Are there meaningful individual differences in temporal inconsistency in self-reported personality?

PubMed

Soubelet, Andrea; Salthouse, Timothy A; Oishi, Shigehiro

2014-11-01

The current project had three goals. The first was to examine whether it is meaningful to refer to across-time variability in self-reported personality as an individual differences characteristic. The second was to investigate whether negative affect was associated with variability in self-reported personality, while controlling for mean levels, and correcting for measurement errors. The third goal was to examine whether variability in self-reported personality would be larger among young adults than among older adults, and whether the relation of variability with negative affect would be stronger at older ages than at younger ages. Two moderately large samples of participants completed the International Item Pool Personality questionnaire assessing the Big Five personality dimensions either twice or thrice, in addition to several measures of negative affect. Results were consistent with the hypothesis that within-person variability in self-reported personality is a meaningful individual difference characteristic. Some people exhibited greater across-time variability than others after removing measurement error, and people who showed temporal instability in one trait also exhibited temporal instability across the other four traits. However, temporal variability was not related to negative affect, and there was no evidence that either temporal variability or its association with negative affect varied with age.

Within-individual correlations reveal link between a behavioral syndrome, condition and cortisol in free-ranging Belding's ground squirrels

PubMed Central

Brooks, Katherine C.; Mateo, Jill. M.

2014-01-01

Animals often exhibit consistent individual differences in behavior (i.e. animal personality) and correlations between behaviors (i.e. behavioral syndromes), yet the causes of those patterns of behavioral variation remain insufficiently understood. Many authors hypothesize that state-dependent behavior produces animal personality and behavioral syndromes. However, empirical studies assessing patterns of covariation among behavioral traits and state variables have produced mixed results. New statistical methods that partition correlations into between-individual and residual within-individual correlations offer an opportunity to more sufficiently quantify relationships among behaviors and state variables to assess hypotheses of animal personality and behavioral syndromes. In a population of wild Belding's ground squirrels (Urocitellus beldingi) we repeatedly measured activity, exploration, and response to restraint behaviors alongside glucocorticoids and nutritional condition. We used multivariate mixed models to determine whether between-individual or within-individual correlations drive phenotypic relationships among traits. Squirrels had consistent individual differences for all five traits. At the between-individual level, activity and exploration were positively correlated whereas both traits negatively correlated with response to restraint, demonstrating a behavioral syndrome. At the within-individual level, condition negatively correlated with cortisol, activity and exploration. Importantly, this indicates that although behavior is state-dependent, which may play a role in animal personality and behavioral syndromes, feedback mechanisms between condition and behavior appear not to produce consistent individual differences in behavior and correlations between them. PMID:25598565

When is affect variability bad for health? The association between affect variability and immune response to the influenza vaccination.

PubMed

Jenkins, Brooke N; Hunter, John F; Cross, Marie P; Acevedo, Amanda M; Pressman, Sarah D

2018-01-01

This study addresses methodological and theoretical questions about the association between affect and physical health. Specifically, we examine the role of affect variability and its interaction with mean levels of affect to predict antibody (Ab) levels in response to an influenza vaccination. Participants (N=83) received the vaccination and completed daily diary measures of affect four times a day for 13days. At one and four months post-vaccination, blood was collected from the participants to assess Ab levels. Findings indicate that affect variability and its interaction with mean levels of affect predict an individual's immune response. Those high in mean positive affect (PA) who had more PA variability were more likely to have a lower Ab response in comparison to those who had high mean PA and less PA variability. Although it did not interact with mean negative affect (NA), NA variability on its own was associated with Ab response, whereby those with less NA variability mounted a more robust immune response. Affect variability is related to immune response to an influenza vaccination and, in some cases, interacts with mean levels of affect. These oscillations in affective experiences are critical to consider in order to unpack the intricacies of how affect influences health. These findings suggest that future researchers should consider the important role of affect variability on physical health-relevant outcomes as well as examine the moderating effect of mean affect levels. Copyright © 2017 Elsevier Inc. All rights reserved.

Air pollution, neighbourhood and maternal-level factors modify the effect of smoking on birth weight: a multilevel analysis in British Columbia, Canada.

PubMed

Erickson, Anders C; Ostry, Aleck; Chan, Hing Man; Arbour, Laura

2016-07-16

Maternal smoking during pregnancy negatively impacts fetal growth, but the effect is not homogenous across the population. We sought to determine how the relationship between cigarette use and fetal growth is modified by the social and physical environment. Birth records with covariates were obtained from the BC Perinatal Database Registry (N = 232,291). Maternal smoking status was self-reported as the number of cigarettes smoked per day usually at the first prenatal care visit. Census dissemination areas (DAs) were used as neighbourhood-level units and linked to individual births using residential postal codes to assign exposure to particulate air pollution (PM 2.5 ) and neighbourhood-level attributes such as socioeconomic status (SES), proportion of post-secondary education, immigrant density and living in a rural place. Random coefficient models were used with cigarettes/day modeled with a random slope to estimate its between-DA variability and test cross-level interactions with the neighbourhood-level variables on continuous birth weight. A significant negative and non-linear association was found between maternal smoking and birth weight. There was significant between-DA intercept variability in birth weight as well as between-DA slope variability of maternal smoking on birth weight of which 68 and 30 % respectively was explained with the inclusion of DA-level variables and their cross-level interactions. High DA-level SES had a strong positive association with birth weight but the effect was moderated with increased cigarettes/day. Conversely, heavy smokers showed the largest increases in birth weight with rising neighbourhood education levels. Increased levels of PM 2.5 and immigrant density were negatively associated with birth weight, but showed positive interactions with increased levels of smoking. Older maternal age and suspected drug or alcohol use both had negative interactions with increased levels of maternal smoking. Maternal smoking had a negative and non-linear dose-response association with birth weight which was highly variable between neighbourhoods and evidence of effect modification with neighbourhood-level factors. These results suggest that focusing exclusively on individual behaviours may have limited success in improving outcomes without addressing the contextual influences at the neighbourhood-level. Further studies are needed to corroborate our findings and to understand how neighbourhood-level attributes interact with smoking to affect birth outcomes.

A Neighborhood Wealth Metric for Use in Health Studies

PubMed Central

Moudon, Anne Vernez; Cook, Andrea J.; Ulmer, Jared; Hurvitz, Philip M.; Drewnowski, Adam

2011-01-01

Background Measures of neighborhood deprivation used in health research are typically based on conventional area-based SES. Purpose The aim of this study is to examine new data and measures of SES for use in health research. Specifically, assessed property values are introduced as a new individual-level metric of wealth and tested for their ability to substitute for conventional area-based SES as measures of neighborhood deprivation. Methods The analysis was conducted in 2010 using data from 1922 participants in the 2008– 2009 survey of the Seattle Obesity Study (SOS). It compared the relative strength of the association between the individual-level neighborhood wealth metric (assessed property values) and area-level SES measures (including education, income, and percentage above poverty as single variables, and as the composite Singh index) on the binary outcome fair/poor general health status. Analyses were adjusted for gender, categoric age, race, employment status, home ownership, and household income. Results The neighborhood wealth measure was more predictive of fair/poor health status than area-level SES measures, calculated either as single variables or as indices (lower DIC measures for all models). The odds of having a fair/poor health status decreased by 0.85 [0.77, 0.93] per $50,000 increase in neighborhood property values after adjusting for individual-level SES measures. Conclusions The proposed individual-level metric of neighborhood wealth, if replicated in other areas, could replace area-based SES measures, thus simplifying analyses of contextual effects on health. PMID:21665069

Estimating an area-level socioeconomic status index and its association with colonoscopy screening adherence.

PubMed

Wheeler, David C; Czarnota, Jenna; Jones, Resa M

2017-01-01

Socioeconomic status (SES) is often considered a risk factor for health outcomes. SES is typically measured using individual variables of educational attainment, income, housing, and employment variables or a composite of these variables. Approaches to building the composite variable include using equal weights for each variable or estimating the weights with principal components analysis or factor analysis. However, these methods do not consider the relationship between the outcome and the SES variables when constructing the index. In this project, we used weighted quantile sum (WQS) regression to estimate an area-level SES index and its effect in a model of colonoscopy screening adherence in the Minnesota-Wisconsin Metropolitan Statistical Area. We considered several specifications of the SES index including using different spatial scales (e.g., census block group-level, tract-level) for the SES variables. We found a significant positive association (odds ratio = 1.17, 95% CI: 1.15-1.19) between the SES index and colonoscopy adherence in the best fitting model. The model with the best goodness-of-fit included a multi-scale SES index with 10 variables at the block group-level and one at the tract-level, with home ownership, race, and income among the most important variables. Contrary to previous index construction, our results were not consistent with an assumption of equal importance of variables in the SES index when explaining colonoscopy screening adherence. Our approach is applicable in any study where an SES index is considered as a variable in a regression model and the weights for the SES variables are not known in advance.

[Self-rated health in adults: influence of poverty and income inequality in the area of residence].

PubMed

Caicedo, Beatriz; Berbesi Fernández, Dedsy

2015-01-01

To evaluate the influence of income inequality and poverty in the towns of Bogotá, Colombia, on poor self-rated health among their residents. The study was based on a multipurpose survey applied in Bogotá-Colombia. A hierarchical data structure (individuals=level1, locations=level 2) was used to define a logit-type multilevel logistic model. The dependent variable was self-perceived poor health, and local variables were income inequality and poverty. All analyses were controlled for socio-demographic variables and stratified by sex. The prevalence of self-reported fair or poor health in the study population was 23.2%. Women showed a greater risk of ill health, as well as men and women with a low educational level, older persons, those without work in the last week and persons affiliated to the subsidized health system. The highest levels of poverty in the city increased the risk of poor health. Cross-level interactions showed that young women and men with a low education level were the most affected by income inequality in the locality. In Bogotá, there are geographical differences in the perception of health. Higher rates of poverty and income inequality were associated with an increased risk of self-perceived poor health. Notable findings were the large health inequalities at the individual and local levels. Copyright © 2014 SESPAS. Published by Elsevier Espana. All rights reserved.

Behavior of complex mixtures in aquatic environments: a synthesis of PNL ecological research

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

Fickeisen, D.H.; Vaughan, B.E.

1984-06-01

The term complex mixture has been recently applied to energy-related process streams, products and wastes that typically contain hundreds or thousands of individual organic compounds, like petroleum or synthetic fuel oils; but it is more generally applicable. A six-year program of ecological research has focused on four areas important to understanding the environmental behavior of complex mixtures: physicochemical variables, individual organism responses, ecosystems-level determinations, and metabolism. Of these areas, physicochemical variables and organism responses were intensively studied; system-level determinations and metabolism represent more recent directions. Chemical characterization was integrated throughout all areas of the program, and state-of-the-art methods were applied.more » 155 references, 35 figures, 4 tables.« less

Some Statistics for Assessing Person-Fit Based on Continuous-Response Models

ERIC Educational Resources Information Center

Ferrando, Pere Joan

2010-01-01

This article proposes several statistics for assessing individual fit based on two unidimensional models for continuous responses: linear factor analysis and Samejima's continuous response model. Both models are approached using a common framework based on underlying response variables and are formulated at the individual level as fixed regression…

Subject Characteristics and Preferences for Different Approaches to Psychotherapy: A Multivariate Study

ERIC Educational Resources Information Center

Helweg, Gregory C.; Gaines, Lawrence S.

1977-01-01

Selected personality variables, sex, age, interpersonal values, and educational level, were examined as antecedents to preferences for a nondirective (Carl Rogers) or directive (Albert Ellis) therapist. Individuals who preferred the Ellis presentation proved to more dogmatic and externalized than individuals preferring the Rogers presentation.…

The neurobiology of individuality

NASA Astrophysics Data System (ADS)

de Bivort, Benjamin

2015-03-01

Individuals often display conspicuously different patterns of behavior, even when they are very closely related genetically. These differences give rise to our sense of individuality, but what is their molecular and neurobiological basis? Individuals that are nominally genetically identical differ at various molecular and neurobiological levels: cell-to-cell variation in somatic genomes, cell-to-cell variation in expression patterns, individual-to-individual variation in neuronal morphology and physiology, and individual-to-individual variation in patterns of brain activity. It is unknown which of these levels is fundamentally causal of behavioral differences. To investigate this problem, we use the fruit fly Drosophila melanogaster, whose genetic toolkit allows the manipulation of each of these mechanistic levels, and whose rapid lifecycle and small size allows for high-throughput automation of behavioral assays. This latter point is crucial; identifying inter-individual behavioral differences requires high sample sizes both within and across individual animals. Automated behavioral characterization is at the heart of our research strategy. In every behavior examined, individual flies have individual behavioral preferences, and we have begun to identify both neural genes and circuits that control the degree of behavioral variability between individuals.

Individual differences in implicit motor learning: task specificity in sensorimotor adaptation and sequence learning

PubMed Central

Raza, Meher; Ivry, Richard B.

2016-01-01

In standard taxonomies, motor skills are typically treated as representative of implicit or procedural memory. We examined two emblematic tasks of implicit motor learning, sensorimotor adaptation and sequence learning, asking whether individual differences in learning are correlated between these tasks, as well as how individual differences within each task are related to different performance variables. As a prerequisite, it was essential to establish the reliability of learning measures for each task. Participants were tested twice on a visuomotor adaptation task and on a sequence learning task, either the serial reaction time task or the alternating reaction time task. Learning was evident in all tasks at the group level and reliable at the individual level in visuomotor adaptation and the alternating reaction time task but not in the serial reaction time task. Performance variability was predictive of learning in both domains, yet the relationship was in the opposite direction for adaptation and sequence learning. For the former, faster learning was associated with lower variability, consistent with models of sensorimotor adaptation in which learning rates are sensitive to noise. For the latter, greater learning was associated with higher variability and slower reaction times, factors that may facilitate the spread of activation required to form predictive, sequential associations. Interestingly, learning measures of the different tasks were not correlated. Together, these results oppose a shared process for implicit learning in sensorimotor adaptation and sequence learning and provide insight into the factors that account for individual differences in learning within each task domain. NEW & NOTEWORTHY We investigated individual differences in the ability to implicitly learn motor skills. As a prerequisite, we assessed whether individual differences were reliable across test sessions. We found that two commonly used tasks of implicit learning, visuomotor adaptation and the alternating serial reaction time task, exhibited good test-retest reliability in measures of learning and performance. However, the learning measures did not correlate between the two tasks, arguing against a shared process for implicit motor learning. PMID:27832611

Finite element analysis to investigate variability of MR elastography in the human thigh.

PubMed

Hollis, L; Barnhill, E; Perrins, M; Kennedy, P; Conlisk, N; Brown, C; Hoskins, P R; Pankaj, P; Roberts, N

2017-11-01

To develop finite element analysis (FEA) of magnetic resonance elastography (MRE) in the human thigh and investigate inter-individual variability of measurement of muscle mechanical properties. Segmentation was performed on MRI datasets of the human thigh from 5 individuals and FEA models consisting of 12 muscles and surrounding tissue created. The same material properties were applied to each tissue type and a previously developed transient FEA method of simulating MRE using Abaqus was performed at 4 frequencies. Synthetic noise was applied to the simulated data at various levels before inversion was performed using the Elastography Software Pipeline. Maps of material properties were created and visually assessed to determine key features. The coefficient of variation (CoV) was used to assess the variability of measurements in each individual muscle and in the groups of muscles across the subjects. Mean measurements for the set of muscles were ranked in size order and compared with the expected ranking. At noise levels of 2% the CoV in measurements of |G * | ranged from 5.3 to 21.9% and from 7.1 to 36.1% for measurements of ϕ in the individual muscles. A positive correlation (R 2 value 0.80) was attained when the expected and measured |G * | ranking were compared, whilst a negative correlation (R 2 value 0.43) was found for ϕ. Created elastograms demonstrated good definition of muscle structure and were robust to noise. Variability of measurements across the 5 subjects was dramatically lower for |G * | than it was for ϕ. This large variability in ϕ measurements was attributed to artefacts. Copyright © 2017 Elsevier Inc. All rights reserved.

Licit prescription drug use in a Swedish population according to age, gender and socioeconomic status after adjusting for level of multi-morbidity

PubMed Central

2012-01-01

Background There is a great variability in licit prescription drug use in the population and among patients. Factors other than purely medical ones have proven to be of importance for the prescribing of licit drugs. For example, individuals with a high age, female gender and low socioeconomic status are more likely to use licit prescription drugs. However, these results have not been adjusted for multi-morbidity level. In this study we investigate the odds of using licit prescription drugs among individuals in the population and the rate of licit prescription drug use among patients depending on gender, age and socioeconomic status after adjustment for multi-morbidity level. Methods The study was carried out on the total population aged 20 years or older in Östergötland county with about 400 000 inhabitants in year 2006. The Johns Hopkins ACG Case-mix was used as a proxy for the individual level of multi-morbidity in the population to which we have related the odds ratio for individuals and incidence rate ratio (IRR) for patients of using licit prescription drugs, defined daily doses (DDDs) and total costs of licit prescription drugs after adjusting for age, gender and socioeconomic factors (educational and income level). Results After adjustment for multi-morbidity level male individuals had less than half the odds of using licit prescription drugs (OR 0.41 (95% CI 0.40-0.42)) compared to female individuals. Among the patients, males had higher total costs (IRR 1.14 (95% CI 1.13-1.15)). Individuals above 80 years had nine times the odds of using licit prescription drugs (OR 9.09 (95% CI 8.33-10.00)) despite adjustment for multi-morbidity. Patients in the highest education and income level had the lowest DDDs (IRR 0.78 (95% CI 0.76-0.80), IRR 0.73 (95% CI 0.71-0.74)) after adjustment for multi-morbidity level. Conclusions This paper shows that there is a great variability in licit prescription drug use associated with gender, age and socioeconomic status, which is not dependent on level of multi-morbidity. PMID:22846625

Does mental health staffing level affect antipsychotic prescribing? Analysis of Italian national statistics.

PubMed

Starace, Fabrizio; Mungai, Francesco; Barbui, Corrado

2018-01-01

In mental healthcare, one area of major concern identified by health information systems is variability in antipsychotic prescribing. While most studies have investigated patient- and prescriber-related factors as possible reasons for such variability, no studies have investigated facility-level characteristics. The present study ascertained whether staffing level is associated with antipsychotic prescribing in community mental healthcare. A cross-sectional analysis of data extracted from the Italian national mental health information system was carried out. For each Italian region, it collects data on the availability and use of mental health facilities. The rate of individuals exposed to antipsychotic drugs was tested for evidence of association with the rate of mental health staff availability by means of univariate and multivariate analyses. In Italy there were on average nearly 60 mental health professionals per 100,000 inhabitants, with wide regional variations (range 21 to 100). The average rate of individuals prescribed antipsychotic drugs was 2.33%, with wide regional variations (1.04% to 4.01%). Univariate analysis showed that the rate of individuals prescribed antipsychotic drugs was inversely associated with the rate of mental health professionals available in Italian regions (Kendall's tau -0.438, p = 0.006), with lower rates of antipsychotic prescriptions in regions with higher rates of mental health professionals. After adjustment for possible confounders, the total availability of mental health professionals was still inversely associated with the rate of individuals exposed to antipsychotic drugs. The evidence that staffing level was inversely associated with antipsychotic prescribing indicates that any actions aimed at decreasing variability in antipsychotic prescribing need to take into account aspects related to the organization of the mental health system.

Determinants of Awareness, Consideration, and Choice Set Size in University Choice.

ERIC Educational Resources Information Center

Dawes, Philip L.; Brown, Jennifer

2002-01-01

Developed and tested a model of students' university "brand" choice using five individual-level variables (ethnic group, age, gender, number of parents going to university, and academic ability) and one situational variable (duration of search) to explain variation in the sizes of awareness, consideration, and choice decision sets. (EV)

Development and Testing of an Initial Model of Curricular Leadership Culture in Middle Schools

ERIC Educational Resources Information Center

Adams, Jerry

2007-01-01

Effective school studies, for the most part, have focused on different individual school-level independent variables influencing student achievement and have largely neglected examining contextual variables within the school or school community that may evolve as a result of responding to statewide accountability pressures, including examining how…

Physically Active Adults: An Analysis of the Key Variables That Keep Them Moving

ERIC Educational Resources Information Center

Downs, Andrew

2016-01-01

Background: A large proportion of adults are insufficiently physically active, and researchers have yet to determine the factors that enable individuals to maintain adequate levels of physical activity throughout adulthood. Purpose: This study sought to identify the key variables linked with consistent physical activity in adulthood as elucidated…

Rapid-estimation method for assessing scour at highway bridges

USGS Publications Warehouse

Holnbeck, Stephen R.

1998-01-01

A method was developed by the U.S. Geological Survey for rapid estimation of scour at highway bridges using limited site data and analytical procedures to estimate pier, abutment, and contraction scour depths. The basis for the method was a procedure recommended by the Federal Highway Administration for conducting detailed scour investigations, commonly referred to as the Level 2 method. Using pier, abutment, and contraction scour results obtained from Level 2 investigations at 122 sites in 10 States, envelope curves and graphical relations were developed that enable determination of scour-depth estimates at most bridge sites in a matter of a few hours. Rather than using complex hydraulic variables, surrogate variables more easily obtained in the field were related to calculated scour-depth data from Level 2 studies. The method was tested by having several experienced individuals apply the method in the field, and results were compared among the individuals and with previous detailed analyses performed for the sites. Results indicated that the variability in predicted scour depth among individuals applying the method generally was within an acceptable range, and that conservatively greater scour depths generally were obtained by the rapid-estimation method compared to the Level 2 method. The rapid-estimation method is considered most applicable for conducting limited-detail scour assessments and as a screening tool to determine those bridge sites that may require more detailed analysis. The method is designed to be applied only by a qualified professional possessing knowledge and experience in the fields of bridge scour, hydraulics, and flood hydrology, and having specific expertise with the Level 2 method.

Social Capital and Fear of Crime in Adolescence: A Multilevel Study.

PubMed

Vieno, Alessio; Lenzi, Michela; Roccato, Michele; Russo, Silvia; Monaci, Maria Grazia; Scacchi, Luca

2016-09-01

Hierarchical linear modeling was used to examine the relationships between social capital (at the individual, the neighborhood, and the regional levels) and adolescents' fear of crime, while controlling for the main individual (sociodemographics, television viewing, and bullying victimization), neighborhood (neighborhood size and aggregated victimization), and regional (crime rate and level of urbanization) variables. Data were analyzed using a three-level model based on 22,639 15.7-year-old (SD = 0.67) students nested within 1081 neighborhoods and 19 Italian regions. The findings revealed that individual and contextual measures of social capital, modeled at the individual, neighborhood, and regional levels simultaneously, showed negative associations with adolescents' fear of crime. Males and participants with higher family affluence were less likely to feel fear of crime, whereas victimization, both at the individual and neighborhood levels, had a positive association with fear of crime. Strengths, limitations, and potential applications of the study are discussed. © Society for Community Research and Action 2016.

The Mediating and Moderating Effects of Workplace Social Capital on the Associations between Adverse Work Characteristics and Psychological Distress among Japanese Workers

PubMed Central

OSHIO, Takashi; INOUE, Akiomi; TSUTSUMI, Akizumi

2014-01-01

Our current study investigated how workplace social capital (WSC) mediates and moderates the associations between adverse work characteristics and psychological distress among Japanese workers. We collected cross-sectional data (N=9,350) from a baseline survey of an occupational Japanese cohort study. We focused on individual WSC and considered job demands/control, effort/reward, and two types (i.e., procedural and interactional) of organizational justice as work-characteristic variables. We defined psychological distress as a score of ≥5 on the Kessler Psychological Distress Scale (K6 scale). Multivariate logistic regression analyses predicted a binary variable of psychological distress by individual WSC and adverse work characteristics, adjusting for individual-level covariates. Individual WSC mediated the associations between adverse work characteristics and psychological distress in almost all model specifications. Additionally, individual WSC moderated the associations of psychological distress with high job demands, high effort, and low interactional justice when we used a high WSC cutoff point. In contrast, individual WSC did not moderate such interactions with low job control, reward, or procedural justice. We concluded that individual WSC mediated the associations between adverse work characteristics and psychological distress among Japanese workers while selectively moderating their associations at high levels of WSC. PMID:24705803

Trustful societies, trustful individuals, and health: An analysis of self-rated health and social trust using the World Value Survey.

PubMed

Jen, Min Hua; Sund, Erik R; Johnston, Ron; Jones, Kelvyn

2010-09-01

This study analyses the relationships between self-rated health and both individual and mean national social trust, focusing on a variant of Wilkinson's hypothesis that individuals will be less healthy the greater the lack of social cohesion in a country. It employs multilevel modelling on World Values Survey data across 69 countries with a total sample of 160,436 individuals. The results show that self-rated health are positively linked to social trust at both country and individual levels after controlling for individual socio-demographic and income variables plus individual social trust; increased trust is associated with better health. Moreover, this analysis of social trust gives some insight into distinctive results for the former Soviet Bloc countries, which have high reported levels of poor health, alongside the Scandinavian countries which have high levels of trust and better health situations. Our results support and extend the Wilkinson hypothesis that the level of trust, an indicator of social cohesion, is predictive of individuals' health. Copyright 2010 Elsevier Ltd. All rights reserved.

Exploring individual cognitions, self-regulation skills, and environmental-level factors as mediating variables of two versions of a Web-based computer-tailored nutrition education intervention aimed at adults: A randomized controlled trial.

PubMed

Springvloet, Linda; Lechner, Lilian; Candel, Math J J M; de Vries, Hein; Oenema, Anke

2016-03-01

This study explored whether the determinants that were targeted in two versions of a Web-based computer-tailored nutrition education intervention mediated the effects on fruit, high-energy snack, and saturated fat intake among adults who did not comply with dietary guidelines. A RCT was conducted with a basic (tailored intervention targeting individual cognitions and self-regulation), plus (additionally targeting environmental-level factors), and control group (generic nutrition information). Participants were recruited from the general Dutch adult population and randomly assigned to one of the study groups. Online self-reported questionnaires assessed dietary intake and potential mediating variables (behavior-specific cognitions, action- and coping planning, environmental-level factors) at baseline and one (T1) and four (T2) months post-intervention (i.e. four and seven months after baseline). The joint-significance test was used to establish mediating variables at different time points (T1-mediating variables - T2-intake; T1-mediating variables - T1-intake; T2-mediating variables - T2-intake). Educational differences were examined by testing interaction terms. The effect of the plus version on fruit intake was mediated (T2-T2) by intention and fruit availability at home and for high-educated participants also by attitude. Among low/moderate-educated participants, high-energy snack availability at home mediated (T1-T1) the effect of the basic version on high-energy snack intake. Subjective norm mediated (T1-T1) the effect of the basic version on fat intake among high-educated participants. Only some of the targeted determinants mediated the effects of both intervention versions on fruit, high-energy snack, and saturated fat intake. A possible reason for not finding a more pronounced pattern of mediating variables is that the educational content was tailored to individual characteristics and that participants only received feedback for relevant and not for all assessed mediating variables. Netherlands Trial Registry NTR3396. Copyright © 2015. Published by Elsevier Ltd.

Variability modifies life satisfaction's association with mortality risk in older adults

PubMed Central

Boehm, Julia K.; Winning, Ashley; Segerstrom, Suzanne; Kubzansky, Laura D.

2015-01-01

Life satisfaction is associated with greater longevity, but its variability across time has not been examined relative to longevity. We investigated whether mean levels of life satisfaction across time, variability in life satisfaction across time, and their interaction were associated with mortality over 9 years of follow-up. Participants were 4,458 Australians initially ≥50 years old. During the follow-up, 546 people died. Adjusting for age, greater mean life satisfaction was associated with reduced risk and greater variability in life satisfaction was associated with increased risk of mortality. These findings were qualified by a significant interaction such that individuals with low mean satisfaction and high variability in satisfaction had the greatest risk of mortality over the follow-up period. In combination with mean levels of life satisfaction, variability in life satisfaction is relevant for mortality risk among older adults. Considering intraindividual variability provides additional insight into associations between psychological characteristics and health. PMID:26048888

Cultural change and traditional ecological knowledge. An empirical analysis from the Tsimane' in the Bolivian Amazon.

PubMed

Reyes-García, Victoria; Paneque-Gálvez, Jaime; Luz, Ana C; Gueze, Maximilien; Macía, Manuel J; Orta-Martínez, Martí; Pino, Joan

2014-01-01

Among the different factors associated to change in traditional ecological knowledge, the study of the relations between cultural change and traditional ecological knowledge has received scan and inadequate scholarly attention. Using data from indigenous peoples of an Amazonian society facing increasing exposure to the mainstream Bolivian society, we analyzed the relation between traditional ecological knowledge, proxied with individual plant use knowledge (n=484), and cultural change, proxied with individual- and village-level (n=47) measures of attachment to traditional beliefs and values. We found that both the individual level of detachment to traditional values and the village level of agreement in detachment to traditional values were associated with individual levels of plant use knowledge, irrespective of other proxy measures for cultural change. Because both the individual- and the village-level variables bear statistically significant associations with plant use knowledge, our results suggest that both the individual- and the supra-individual level processes of cultural change are related to the erosion of plant use knowledge. Results from our work highlight the importance of analyzing processes that happen at intermediary social units -the village in our case study- to explain changes in traditional ecological knowledge.

Cultural change and traditional ecological knowledge. An empirical analysis from the Tsimane’ in the Bolivian Amazon

PubMed Central

Reyes-García, Victoria; Paneque-Gálvez, Jaime; Luz, Ana C.; Gueze, Maximilien; Macía, Manuel J.; Orta-Martínez, Martí; Pino, Joan

2016-01-01

Among the different factors associated to change in traditional ecological knowledge, the study of the relations between cultural change and traditional ecological knowledge has received scan and inadequate scholarly attention. Using data from indigenous peoples of an Amazonian society facing increasing exposure to the mainstream Bolivian society, we analyzed the relation between traditional ecological knowledge, proxied with individual plant use knowledge (n=484), and cultural change, proxied with individual- and village-level (n=47) measures of attachment to traditional beliefs and values. We found that both the individual level of detachment to traditional values and the village level of agreement in detachment to traditional values were associated with individual levels of plant use knowledge, irrespective of other proxy measures for cultural change. Because both the individual- and the village-level variables bear statistically significant associations with plant use knowledge, our results suggest that both the individual- and the supra-individual level processes of cultural change are related to the erosion of plant use knowledge. Results from our work highlight the importance of analyzing processes that happen at intermediary social units -the village in our case study- to explain changes in traditional ecological knowledge. PMID:27642188

Cortical Brain Atrophy and Intra-Individual Variability in Neuropsychological Test Performance in HIV Disease

PubMed Central

HINES, Lindsay J.; MILLER, Eric N.; HINKIN, Charles H.; ALGER, Jeffery R.; BARKER, Peter; GOODKIN, Karl; MARTIN, Eileen M.; MARUCA, Victoria; RAGIN, Ann; SACKTOR, Ned; SANDERS, Joanne; SELNES, Ola; BECKER, James T.

2015-01-01

Objective To characterize the relationship between dispersion-based intra-individual variability (IIVd) in neuropsychological test performance and brain volume among HIV seropositive and seronegative men and to determine the effects of cardiovascular risk and HIV infection on this relationship. Methods Magnetic Resonance Imaging (MRI) was used to acquire high-resolution neuroanatomic data from 147 men age 50 and over, including 80 HIV seropositive (HIV+) and 67 seronegative controls (HIV−) in this cross-sectional cohort study. Voxel Based Morphometry was used to derive volumetric measurements at the level of the individual voxel. These brain structure maps were analyzed using Statistical Parametric Mapping (SPM2). IIVd was measured by computing intra-individual standard deviations (ISD’s) from the standardized performance scores of five neuropsychological tests: Wechsler Memory Scale-III Visual Reproduction I and II, Logical Memory I and II, Wechsler Adult Intelligence Scale-III Letter Number Sequencing. Results Total gray matter (GM) volume was inversely associated with IIVd. Among all subjects, IIVd -related GM atrophy was observed primarily in: 1) the inferior frontal gyrus bilaterally, the left inferior temporal gyrus extending to the supramarginal gyrus, spanning the lateral sulcus; 2) the right superior parietal lobule and intraparietal sulcus; and, 3) dorsal/ventral regions of the posterior section of the transverse temporal gyrus. HIV status, biological, and cardiovascular disease (CVD) variables were not linked to IIVd -related GM atrophy. Conclusions IIVd in neuropsychological test performance may be a sensitive marker of cortical integrity in older adults, regardless of HIV infection status or CVD risk factors, and degree of intra-individual variability links with volume loss in specific cortical regions; independent of mean-level performance on neuropsychological tests. PMID:26303224

Regional contextual influences on short sleep duration: a 50 universities population-based multilevel study in China.

PubMed

Yang, Tingzhong; Peng, Sihui; Barnett, Ross; Zhang, Chichen

2018-01-01

Ecological models have emphasized that short sleep duration (SSD) is influenced by both individual and environmental variables. However, few studies have considered the latter. The present study explores the influence of urban and regional contextual factors, net of individual characteristics, on the prevalence of SSD among university students in China. Participants were 11,954 students, who were identified through a multistage survey sampling process conducted in 50 universities. Individual data were obtained through a self-administered questionnaire, and contextual variables were retrieved from a national database. Multilevel logistic regression models were used to examine urban and regional variations in high and moderate levels of SSD. Overall the prevalence of high SSD (<6 hours sleep duration) was 2.8% (95% CI: 1.7%,3.9%) and moderate SSD (<7 hours) 24.7% (95% CI: 19.5%, 29.8%). Multilevel logistic regressions confirmed that home region gross domestic product (GDP) and the university regional unemployment rate were associated with SSD, net of other individual- and city-level covariates. Students attending high-level universities also recorded the highest levels of SSD. Of the individual characteristcs, only mother's occupation and student mental health status were related to SSD. The results of this study add important insights about the role of contextual factors affecting SSD among young adults and indicate the need to take into account both past, as well as present, environmental influences to control SSD.

Drugs meeting the molecular basis of diabetic kidney disease: bridging from molecular mechanism to personalized medicine.

PubMed

Lambers Heerspink, Hiddo J; Oberbauer, Rainer; Perco, Paul; Heinzel, Andreas; Heinze, Georg; Mayer, Gert; Mayer, Bernd

2015-08-01

Diabetic kidney disease (DKD) is a complex, multifactorial disease and is associated with a high risk of renal and cardiovascular morbidity and mortality. Clinical practice guidelines for diabetes recommend essentially identical treatments for all patients without taking into account how the individual responds to the instituted therapy. Yet, individuals vary widely in how they respond to medications and therefore optimal therapy differs between individuals. Understanding the underlying molecular mechanisms of variability in drug response will help tailor optimal therapy. Polymorphisms in genes related to drug pharmacokinetics have been used to explore mechanisms of response variability in DKD, but with limited success. The complex interaction between genetic make-up and environmental factors on the abundance of proteins and metabolites renders pharmacogenomics alone insufficient to fully capture response variability. A complementary approach is to attribute drug response variability to individual variability in underlying molecular mechanisms involved in the progression of disease. The interplay of different processes (e.g. inflammation, fibrosis, angiogenesis, oxidative stress) appears to drive disease progression, but the individual contribution of each process varies. Drugs at the other hand address specific targets and thereby interfere in certain disease-associated processes. At this level, biomarkers may help to gain insight into which specific pathophysiological processes are involved in an individual followed by a rational assessment whether a specific drug's mode of action indeed targets the relevant process at hand. This article describes the conceptual background and data-driven workflow developed by the SysKid consortium aimed at improving characterization of the molecular mechanisms underlying DKD at the interference of the molecular impact of individual drugs in order to tailor optimal therapy to individual patients. © The Author 2015. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

To be so bold: boldness is repeatable and related to within individual behavioural variability in North Island robins.

PubMed

He, Ruchuan; Pagani-Núñez, Emilio; Chevallier, Clément; Barnett, Craig R A

2017-07-01

Behavioural research traditionally focusses on the mean responses of a group of individuals rather than variation in behaviour around the mean or among individuals. However, examining the variation in behaviour among and within individuals may also yield important insights into the evolution and maintenance of behaviour. Repeatability is the most commonly used measure of variability among individuals in behavioural research. However, there are other forms of variation within populations that have received less attention. One such measure is intraindividual variation in behaviour (IIV), which is a short-term fluctuation of within-individual behaviour. Such variation in behaviour might be important during interactions because it could decrease the ability of conspecific and heterospecific individuals to predict the behaviour of the subject, thus increasing the cost of the interaction. In this experiment, we made repeated measures of the latency of North Island robins to attack a prey in a novel situation (a form of boldness) and examined (i) repeatability of boldness (the propensity to take a risk), (ii) IIV of boldness, and (iii) whether there was a significant relationship between these two traits (a behavioural syndrome). We found that boldness was highly repeatable, that there were high levels of IIV in boldness, and that there was a negative relationship between boldness and IIV in boldness. This suggests that despite high levels of repeatability for this behaviour, there were also still significant differences in IIV among different individuals within the population. Moreover, bolder individuals had significantly less IIV in their boldness, which suggests that they were forming routines (which reduces behavioural variability) compared to shyer individuals. Our results definitively demonstrate that IIV itself varies across individuals and is linked with key behavioural traits, and we argue for the importance of future studies aimed at understanding its causes and consequences for behavioural interactions. Copyright © 2017 Elsevier B.V. All rights reserved.

Understanding Recession and Self-Rated Health with the Partial Proportional Odds Model: An Analysis of 26 Countries

PubMed Central

Mayer, Adam; Foster, Michelle

2015-01-01

Introduction Self-rated health is demonstrated to vary substantially by both personal socio-economic status and national economic conditions. However, studies investigating the combined influence of individual and country level economic indicators across several countries in the context of recent global recession are limited. This paper furthers our knowledge of the effect of recession on health at both the individual and national level. Methods Using the Life in Transition II study, which provides data from 19,759 individuals across 26 European nations, we examine the relationship between self-rated health, personal economic experiences, and macro-economic change. Data analyses include, but are not limited to, the partial proportional odds model which permits the effect of predictors to vary across different levels of our dependent variable. Results Household experiences with recession, especially a loss of staple good consumption, are associated with lower self-rated health. Most individual-level experiences with recession, such as a job loss, have relatively small negative effects on perceived health; the effect of individual or household economic hardship is strongest in high income nations. Our findings also suggest that macroeconomic growth improves self-rated health in low-income nations but has no effect in high-income nations. Individuals with the greatest probability of “good” self-rated health reside in wealthy countries ($23,910 to $50, 870 GNI per capita). Conclusion Both individual and national economic variables are predictive of self-rated health. Personal and household experiences are most consequential for self-rated health in high income nations, while macroeconomic growth is most consequential in low-income nations. PMID:26513660

Social inequalities in alcohol consumption in the Czech Republic: a multilevel analysis.

PubMed

Dzúrová, Dagmara; Spilková, Jana; Pikhart, Hynek

2010-05-01

Czech Republic traditionally ranks among the countries with the highest alcohol, consumption. This paper examines both risk and protective factors for frequent of alcohol, consumption in the Czech population using multilevel analysis. Risk factors were measured at the, individual level and at the area level. The individual-level data were obtained from a survey for a, sample of 3526 respondents aged 18-64 years. The area-level data were obtained from the Czech, Statistical Office. The group most inclinable to risk alcohol consumption and binge drinking are mainly, men, who live as single, with low education and also unemployed. Only the variable for divorce rate, showed statistical significance at both levels, thus the individual and the aggregated one. No cross-level interactions were found to be statistically significant. Copyright 2010 Elsevier Ltd. All rights reserved.

Patterns of drought tolerance in major European temperate forest trees: climatic drivers and levels of variability.

PubMed

Zang, Christian; Hartl-Meier, Claudia; Dittmar, Christoph; Rothe, Andreas; Menzel, Annette

2014-12-01

The future performance of native tree species under climate change conditions is frequently discussed, since increasingly severe and more frequent drought events are expected to become a major risk for forest ecosystems. To improve our understanding of the drought tolerance of the three common European temperate forest tree species Norway spruce, silver fir and common beech, we tested the influence of climate and tree-specific traits on the inter and intrasite variability in drought responses of these species. Basal area increment data from a large tree-ring network in Southern Germany and Alpine Austria along a climatic cline from warm-dry to cool-wet conditions were used to calculate indices of tolerance to drought events and their variability at the level of individual trees and populations. General patterns of tolerance indicated a high vulnerability of Norway spruce in comparison to fir and beech and a strong influence of bioclimatic conditions on drought response for all species. On the level of individual trees, low-growth rates prior to drought events, high competitive status and low age favored resilience in growth response to drought. Consequently, drought events led to heterogeneous and variable response patterns in forests stands. These findings may support the idea of deliberately using spontaneous selection and adaption effects as a passive strategy of forest management under climate change conditions, especially a strong directional selection for more tolerant individuals when frequency and intensity of summer droughts will increase in the course of global climate change. © 2014 John Wiley & Sons Ltd.

Variability in reaction time performance of younger and older adults.

PubMed

Hultsch, David F; MacDonald, Stuart W S; Dixon, Roger A

2002-03-01

Age differences in three basic types of variability were examined: variability between persons (diversity), variability within persons across tasks (dispersion), and variability within persons across time (inconsistency). Measures of variability were based on latency performance from four measures of reaction time (RT) performed by a total of 99 younger adults (ages 17--36 years) and 763 older adults (ages 54--94 years). Results indicated that all three types of variability were greater in older compared with younger participants even when group differences in speed were statistically controlled. Quantile-quantile plots showed age and task differences in the shape of the inconsistency distributions. Measures of within-person variability (dispersion and inconsistency) were positively correlated. Individual differences in RT inconsistency correlated negatively with level of performance on measures of perceptual speed, working memory, episodic memory, and crystallized abilities. Partial set correlation analyses indicated that inconsistency predicted cognitive performance independent of level of performance. The results indicate that variability of performance is an important indicator of cognitive functioning and aging.

School differences in adolescent health and wellbeing: findings from the Canadian Health Behaviour in School-aged Children Study.

PubMed

Saab, Hana; Klinger, Don

2010-03-01

The goal of this study was to assess the relationship between student- and school-level factors and student health and wellbeing outcomes, and to estimate the variability present at each of the student and school levels for each of three selected health-related outcomes. The data are from the 2006 Canadian Health Behaviour in School-aged children (HBSC) study in which Grades 6-10 students (N=9670) and administrators (N=187) were surveyed. The three outcome measures are Self-Rated Health (SRH), Emotional Wellbeing (EWB), and Subjective Health Complaints (SHC). Individual and school-level effects on the three outcomes were estimated using multi-level modeling. Both individual and school-level factors were associated with students' health. Gender, family wealth, family structure, academic achievement and neighbourhood were significant student-level predictors. We identified random associations between the student-level variables and reported health outcomes. These random effects indicate that the relationships between these student variables and health are not consistent across schools. Student Problem Behaviours at the school were significant predictors of SRH and SHC, while Student Aggression and the school's average socioeconomic standing were significant school-level predictors of EWB. Findings suggest that the environment and disciplinary climate in schools can predict student health and wellbeing outcomes, and may have important implications for school initiatives aimed at students who are struggling both emotionally and academically. Copyright 2009 Elsevier Ltd. All rights reserved.

Application of the theory of reasoned action to environmental behaviors

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

Duquette, R.D.

The applicability of Ajzen and Fishbein's Theory of Reasoned Action (1980) to environmental behaviors was examined. Trained interviewers conducted a telephone survey employing random digit dialing with random selection of individuals within households; 388 individuals completed interviews. A preliminary study was conducted to identify salient outcomes (advantages and disadvantages), referents (individuals or groups), and activities associated with protecting the environment. The main study questionnaire was based upon the most frequently identified outcomes, referents, and activities, using the procedures of Ajzen and Fishbein (1980). A pilot test indicated that the ..cap alpha.. coefficients of all subscales were greater than .70. Inmore » addition to the theory variables, the external variables of occupation and education were assessed. The relationships between the theory variables were examined using correlational and multiple regression techniques. Though weaker than in previous studies, all the theoretical relationships were in the hypothesized direction. Analysis of variance, used to examine the external variables, found significant differences among occupational groups and educational levels with regard to intention to protect the environment. Polluters scored lower on intention than individuals with non-polluting or not applicable occupations. Individuals with a high school diploma or less were lower on intention and were significantly less favorable toward protecting the environment than those with some college or a college degree.« less

Cross-Level Effects Between Neurophysiology and Communication During Team Training.

PubMed

Gorman, Jamie C; Martin, Melanie J; Dunbar, Terri A; Stevens, Ronald H; Galloway, Trysha L; Amazeen, Polemnia G; Likens, Aaron D

2016-02-01

We investigated cross-level effects, which are concurrent changes across neural and cognitive-behavioral levels of analysis as teams interact, between neurophysiology and team communication variables under variations in team training. When people work together as a team, they develop neural, cognitive, and behavioral patterns that they would not develop individually. It is currently unknown whether these patterns are associated with each other in the form of cross-level effects. Team-level neurophysiology and latent semantic analysis communication data were collected from submarine teams in a training simulation. We analyzed whether (a) both neural and communication variables change together in response to changes in training segments (briefing, scenario, or debriefing), (b) neural and communication variables mutually discriminate teams of different experience levels, and (c) peak cross-correlations between neural and communication variables identify how the levels are linked. Changes in training segment led to changes in both neural and communication variables, neural and communication variables mutually discriminated between teams of different experience levels, and peak cross-correlations indicated that changes in communication precede changes in neural patterns in more experienced teams. Cross-level effects suggest that teamwork is not reducible to a fundamental level of analysis and that training effects are spread out across neural and cognitive-behavioral levels of analysis. Cross-level effects are important to consider for theories of team performance and practical aspects of team training. Cross-level effects suggest that measurements could be taken at one level (e.g., neural) to assess team experience (or skill) on another level (e.g., cognitive-behavioral). © 2015, Human Factors and Ergonomics Society.

The complex reality of sea-level rise in an atoll nation

NASA Astrophysics Data System (ADS)

Donner, S. D.

2012-12-01

Sea-level rise famously poses an existential threat to island nations like Kiribati, Tuvalu and the Maldives. Yet as the global mean sea-level rises, the response of any one location at any given time will depend on the natural variability in regional sea-level and other impact of local human activities on coastal processes. As with climate warming, the state of an individual shoreline or the extent of flooding on a given day is not proof of a sea-level trend, nor is a global sea-level trend a good predictor of individual flooding or erosion events. Failure to consider the effect of natural variability and local human activity on coastal processes often leads to misattribution of flooding events and even some long-term shoreline changes to global sea level rise. Moreover, unverified attribution of individual events or changes to specific islets to sea level rise can inflame or invite scepticism of the strong scientific evidence for an accelerating increase in the global sea level due to the impacts of human activity on the climate system. This is particularly important in developing nations like Kiribati, which are depending on international financial support to adapt to rising sea levels. In this presentation, I use gauge data and examples from seven years of field work in Tarawa Atoll, the densely populated capital of Kiribati, to examine the complexity of local sea level and shoreline change in one of the world's most vulnerable countries. First, I discuss how the combination of El Nino-driven variability in sea-level and the astronomical tidal cycle leads to flooding and erosion events which can be mistaken for evidence of sea-level rise. Second, I show that human modification to shorelines has redirected sediment supply, leading, in some cases, to expansion of islets despite rising sea levels. Taken together, the analysis demonstrates the challenge of attributing particular coastal events to global mean sea-level rise and the impact on decision-making. The presentation concludes with a discussion of the implications for attribution research, discourse about sea-level rise, and adaptation planning.

Inter- and Intra-individual variability following intermittent theta burst stimulation: implications for rehabilitation and recovery.

PubMed

Hinder, Mark R; Goss, Emily L; Fujiyama, Hakuei; Canty, Alison J; Garry, Michael I; Rodger, Jennifer; Summers, Jeffery J

2014-01-01

The continued refinement of non-invasive brain stimulation (NBS) techniques is indicative of promising clinical and rehabilitative interventions that are able to modulate cortical excitability. Intermittent theta burst stimulation (iTBS) is one such technique that can increase cortical excitability, purportedly via LTP-like mechanisms. While iTBS may have the capacity to promote recovery after neurological injury, and to combat cognitive and motor decline, recent reports observed highly variable effects across individuals, questioning the efficacy of iTBS as a clinical tool. The aim of this study was to examine intra-individual reliability and inter-individual variability in responses to iTBS. Thirty healthy participants completed two experimental sessions of the iTBS protocol 1-3 weeks apart. Motor evoked potentials in response to single pulse TMS were used to assess corticospinal excitability prior to, and up to 36 min following, iTBS. At the group level, iTBS evoked statistically significant increases in motor cortical excitability across both sessions (P < 0.001), with 22 out of 30 participants exhibiting increases in excitability in both sessions. A strong intraclass correlation demonstrated that both the direction, and magnitude of the plastic changes were reliable at the individual level. Overall, our results suggest that iTBS is capable of inducing relatively robust and consistent effects within and between young individuals. As such, the capacity for iTBS to be exploited in clinical and rehabilitative interventions should continue to be explored. Copyright © 2014 Elsevier Inc. All rights reserved.

Variations in the perceptions of peer and coach motivational climate.

PubMed

Vazou, Spiridoula

2010-06-01

This study examined (a) variations in the perceptions of peer- and coach-generated motivational climate within and between teams and (b) individual- and group-level factors that can account for these variations. Participants were 483 athletes between 12 and 16 years old. The results showed that perceptions of both peer- and coach-generated climate varied as a function of group-level variables, namely team success, coach's gender (except for peer ego-involving climate), and team type (only for coach ego-involving climate). Perceptions of peer- and coach-generated climate also varied as a function of individual-level variables, namely athletes' task and ego orientations, gender, and age (only for coach task-involving and peer ego-involving climate). Moreover, within-team variations in perceptions of peer- and coach-generated climate as a function of task and ego orientation levels were identified. Identifying and controlling the factors that influence perceptions of peer- and coach-generated climate may be important in strengthening task-involving motivational cues.

Multilevel models in the explanation of the relationship between safety climate and safe behavior.

PubMed

Cheyne, Alistair; Tomás, José M; Oliver, Amparo

2013-01-01

This study examines the relationships between components of organizational safety climate, including employee attitudes to organizational safety issues; perceptions of the physical working environment, and evaluations of worker engagement with safety issues; and relates these to self-reported levels of safety behavior. It attempts to explore the relationships between these variables in 1189 workers across 78 work groups in a large transportation organization. Evaluations of safety climate, the working environment and worker engagement, as well as safe behaviors, were collected using a self report questionnaire. The multilevel analysis showed that both levels of evaluation (the work group and the individual), and some cross-level interactions, were significant in explaining safe behaviors. Analyses revealed that a number of variables, at both levels, were associated with worker engagement and safe behaviors. The results suggest that, while individual evaluations of safety issues are important, there is also a role for the fostering of collective safety climates in encouraging safe behaviors and therefore reducing accidents.

Model of aircraft noise adaptation

NASA Technical Reports Server (NTRS)

Dempsey, T. K.; Coates, G. D.; Cawthorn, J. M.

1977-01-01

Development of an aircraft noise adaptation model, which would account for much of the variability in the responses of subjects participating in human response to noise experiments, was studied. A description of the model development is presented. The principal concept of the model, was the determination of an aircraft adaptation level which represents an annoyance calibration for each individual. Results showed a direct correlation between noise level of the stimuli and annoyance reactions. Attitude-personality variables were found to account for varying annoyance judgements.

Light induced intraspecific variability in response to thermal stress in the hard coral Stylophora pistillata

PubMed Central

Wijgerde, Tim; Dini-Andreote, Francisco; Eriksson, Britas Klemens; Salles, Joana Falcão; Pen, Ido; Wild, Christian

2017-01-01

Recent research suggests that prior exposure of several months to elevated irradiance induces enhanced thermal tolerance in scleractinian corals. While this tolerance has been reported at the species level, individual coral colonies may react differently due to individual variability in thermal tolerance. As thermal anomalies are predicted to become common in the upcoming future, intraspecific variation may be key to the survival of coral populations. In order to study light-history based thermal stress responses on individual colonies, we developed a preliminary microcosm experiment where three randomly chosen, aquacultured colonies of the model coral Stylophora pistillata were exposed to two irradiance treatments (200 and 400 μmol photons m−2 s−1) for 31 days, followed by artificially induced heat stress (∼33.4 °C). We found different responses to occur at both the intraspecific and the intracolonial levels, as indicated by either equal, less severe, delayed, and/or even non-necrotic responses of corals previously exposed to the irradiance of 400 compared to 200 μmol photons m−2 s−1. In addition, all individual colonies revealed light-enhanced calcification. Finally, elevated irradiance resulted in a lower chlorophyll a concentration in one colony compared to the control treatment, and the same colony displayed more rapid bleaching compared to the other ones. Taken together, this study highlights the potential importance of intra-individual variability in physiological responses of scleractinian corals and provides recommendations for improving methodological designs for future studies. PMID:29038747

Sampling intraspecific variability in leaf functional traits: Practical suggestions to maximize collected information.

PubMed

Petruzzellis, Francesco; Palandrani, Chiara; Savi, Tadeja; Alberti, Roberto; Nardini, Andrea; Bacaro, Giovanni

2017-12-01

The choice of the best sampling strategy to capture mean values of functional traits for a species/population, while maintaining information about traits' variability and minimizing the sampling size and effort, is an open issue in functional trait ecology. Intraspecific variability (ITV) of functional traits strongly influences sampling size and effort. However, while adequate information is available about intraspecific variability between individuals (ITV BI ) and among populations (ITV POP ), relatively few studies have analyzed intraspecific variability within individuals (ITV WI ). Here, we provide an analysis of ITV WI of two foliar traits, namely specific leaf area (SLA) and osmotic potential (π), in a population of Quercus ilex L. We assessed the baseline ITV WI level of variation between the two traits and provided the minimum and optimal sampling size in order to take into account ITV WI , comparing sampling optimization outputs with those previously proposed in the literature. Different factors accounted for different amount of variance of the two traits. SLA variance was mostly spread within individuals (43.4% of the total variance), while π variance was mainly spread between individuals (43.2%). Strategies that did not account for all the canopy strata produced mean values not representative of the sampled population. The minimum size to adequately capture the studied functional traits corresponded to 5 leaves taken randomly from 5 individuals, while the most accurate and feasible sampling size was 4 leaves taken randomly from 10 individuals. We demonstrate that the spatial structure of the canopy could significantly affect traits variability. Moreover, different strategies for different traits could be implemented during sampling surveys. We partially confirm sampling sizes previously proposed in the recent literature and encourage future analysis involving different traits.

The contextual effects of social capital on health: a cross-national instrumental variable analysis.

PubMed

Kim, Daniel; Baum, Christopher F; Ganz, Michael L; Subramanian, S V; Kawachi, Ichiro

2011-12-01

Past research on the associations between area-level/contextual social capital and health has produced conflicting evidence. However, interpreting this rapidly growing literature is difficult because estimates using conventional regression are prone to major sources of bias including residual confounding and reverse causation. Instrumental variable (IV) analysis can reduce such bias. Using data on up to 167,344 adults in 64 nations in the European and World Values Surveys and applying IV and ordinary least squares (OLS) regression, we estimated the contextual effects of country-level social trust on individual self-rated health. We further explored whether these associations varied by gender and individual levels of trust. Using OLS regression, we found higher average country-level trust to be associated with better self-rated health in both women and men. Instrumental variable analysis yielded qualitatively similar results, although the estimates were more than double in size in both sexes when country population density and corruption were used as instruments. The estimated health effects of raising the percentage of a country's population that trusts others by 10 percentage points were at least as large as the estimated health effects of an individual developing trust in others. These findings were robust to alternative model specifications and instruments. Conventional regression and to a lesser extent IV analysis suggested that these associations are more salient in women and in women reporting social trust. In a large cross-national study, our findings, including those using instrumental variables, support the presence of beneficial effects of higher country-level trust on self-rated health. Previous findings for contextual social capital using traditional regression may have underestimated the true associations. Given the close linkages between self-rated health and all-cause mortality, the public health gains from raising social capital within and across countries may be large. Copyright © 2011 Elsevier Ltd. All rights reserved.

The contextual effects of social capital on health: a cross-national instrumental variable analysis

PubMed Central

Kim, Daniel; Baum, Christopher F; Ganz, Michael; Subramanian, S V; Kawachi, Ichiro

2011-01-01

Past observational studies of the associations of area-level/contextual social capital with health have revealed conflicting findings. However, interpreting this rapidly growing literature is difficult because estimates using conventional regression are prone to major sources of bias including residual confounding and reverse causation. Instrumental variable (IV) analysis can reduce such bias. Using data on up to 167 344 adults in 64 nations in the European and World Values Surveys and applying IV and ordinary least squares (OLS) regression, we estimated the contextual effects of country-level social trust on individual self-rated health. We further explored whether these associations varied by gender and individual levels of trust. Using OLS regression, we found higher average country-level trust to be associated with better self-rated health in both women and men. Instrumental variable analysis yielded qualitatively similar results, although the estimates were more than double in size in women and men using country population density and corruption as instruments. The estimated health effects of raising the percentage of a country's population that trusts others by 10 percentage points were at least as large as the estimated health effects of an individual developing trust in others. These findings were robust to alternative model specifications and instruments. Conventional regression and to a lesser extent IV analysis suggested that these associations are more salient in women and in women reporting social trust. In a large cross-national study, our findings, including those using instrumental variables, support the presence of beneficial effects of higher country-level trust on self-rated health. Past findings for contextual social capital using traditional regression may have underestimated the true associations. Given the close linkages between self-rated health and all-cause mortality, the public health gains from raising social capital within countries may be large. PMID:22078106

Perceived individual, social, and environmental factors for physical activity and walking.

PubMed

Granner, Michelle L; Sharpe, Patricia A; Hutto, Brent; Wilcox, Sara; Addy, Cheryl L

2007-07-01

Few studies have explored associations of individual, social, and environmental factors with physical activity and walking behavior. A random-digit-dial questionnaire, which included selected individual, social, and environmental variables, was administered to 2025 adults, age 18 y and older, in two adjacent counties in a southeastern state. Logistic regressions were conducted adjusting for age, race, sex, education, and employment. In multivariate models, somewhat different variables were associated with physical activity versus regular walking. Self-efficacy (OR = 19.19), having an exercise partner (OR = 1.47), recreation facilities (OR = 1.54), and safety of trails from crime (OR = 0.72) were associated with physical activity level; while self-efficacy (OR = 4.22), known walking routes (OR = 1.54), recreation facilities (OR = 1.57-1.59), and safety of trails from crime (OR = 0.69) were associated with regular walking behavior. Physical activity and walking behaviors were associated with similar variables in this study.

Hydration level is an internal variable for computing motivation to obtain water rewards in monkeys.

PubMed

Minamimoto, Takafumi; Yamada, Hiroshi; Hori, Yukiko; Suhara, Tetsuya

2012-05-01

In the process of motivation to engage in a behavior, valuation of the expected outcome is comprised of not only external variables (i.e., incentives) but also internal variables (i.e., drive). However, the exact neural mechanism that integrates these variables for the computation of motivational value remains unclear. Besides, the signal of physiological needs, which serves as the primary internal variable for this computation, remains to be identified. Concerning fluid rewards, the osmolality level, one of the physiological indices for the level of thirst, may be an internal variable for valuation, since an increase in the osmolality level induces drinking behavior. Here, to examine the relationship between osmolality and the motivational value of a water reward, we repeatedly measured the blood osmolality level, while 2 monkeys continuously performed an instrumental task until they spontaneously stopped. We found that, as the total amount of water earned increased, the osmolality level progressively decreased (i.e., the hydration level increased) in an individual-dependent manner. There was a significant negative correlation between the error rate of the task (the proportion of trials with low motivation) and the osmolality level. We also found that the increase in the error rate with reward accumulation can be well explained by a formula describing the changes in the osmolality level. These results provide a biologically supported computational formula for the motivational value of a water reward that depends on the hydration level, enabling us to identify the neural mechanism that integrates internal and external variables.

Individual and Contextual Variables among Creative Scientists: The New Work Paradigm

ERIC Educational Resources Information Center

Culross, Rita R.

2004-01-01

This article discusses the individual and contextual factors that are salient to high levels of creativity among scientists working in organizational settings in the modern world. The article contrasts such scientists with traditional depictions of creative scientists and draws implications for future directions for creativity research and for the…

Public Service Motivation as a Predictor of Attraction to the Public Sector

ERIC Educational Resources Information Center

Carpenter, Jacqueline; Doverspike, Dennis; Miguel, Rosanna F.

2012-01-01

According to public service motivation theory, individuals with a strong public service orientation are attracted to government jobs. This proposition was investigated in three studies by measuring public sector motivation at a pre-entry level as an individual difference variable affecting perceptions of fit and organizational attraction. Results…

Evidence of Reflective Thinking across the Curriculum: College Experience versus Individual Courses

ERIC Educational Resources Information Center

Sargent, Carol Springer

2015-01-01

This study investigated how individual and course-level variables across the curriculum at a four-year college (college here refers to a higher education institution that offers undergraduate education but not graduate degrees) in the southeastern US impacted student reflective thinking as measured by Kember and colleagues' [2000. Development of a…

Neighbourhood non-employment and daily smoking: a population-based study of women and men in Sweden.

PubMed

Ohlander, Emma; Vikström, Max; Lindström, Martin; Sundquist, Kristina

2006-02-01

To examine whether neighbourhood non-employment is associated with daily smoking after adjustment for individual characteristics, such as employment status. Cross-sectional study of a simple, random sample of 31,164 women and men aged 25-64, representative of the entire population in Sweden. Data were collected from the years 1993-2000. The individual variables included age, sex, employment status, occupation and housing tenure. Logistic regression was used in the analysis with neighbourhood non-employment rates measured at small area market statistics level. There was a significant association between neighbourhood non-employment rates and daily smoking for both women and men. After adjustment for employment status and housing tenure the odds ratios of daily smoking were 1.39 (95% CI = 1.22-1.58) for women and 1.41 (95% CI = 1.23-1.61) for men living in neighbourhoods with the highest non-employment rates. The individual variables of unemployment, low occupational level and renting were associated with daily smoking. Neighbourhood non-employment is associated with daily smoking. Smoking prevention in primary health care should address both individuals and neighbourhoods.

Variability of cholesterol accessibility in human red blood cells measured using a bacterial cholesterol-binding toxin

PubMed Central

Chakrabarti, Rima S; Ingham, Sally A; Kozlitina, Julia; Gay, Austin; Cohen, Jonathan C; Radhakrishnan, Arun; Hobbs, Helen H

2017-01-01

Cholesterol partitions into accessible and sequestered pools in cell membranes. Here, we describe a new assay using fluorescently-tagged anthrolysin O, a cholesterol-binding bacterial toxin, to measure accessible cholesterol in human red blood cells (RBCs). Accessible cholesterol levels were stable within individuals, but varied >10 fold among individuals. Significant variation was observed among ethnic groups (Blacks>Hispanics>Whites). Variation in accessibility of RBC cholesterol was unrelated to the cholesterol content of RBCs or plasma, but was associated with the phospholipid composition of the RBC membranes and with plasma triglyceride levels. Pronase treatment of RBCs only modestly altered cholesterol accessibility. Individuals on hemodialysis, who have an unexplained increase in atherosclerotic risk, had significantly higher RBC cholesterol accessibility. Our data indicate that RBC accessible cholesterol is a stable phenotype with significant inter-individual variability. Factors both intrinsic and extrinsic to the RBC contribute to variation in its accessibility. This assay provides a new tool to assess cholesterol homeostasis among tissues in humans. DOI: http://dx.doi.org/10.7554/eLife.23355.001 PMID:28169829

Portraying the Contribution of Individual Behaviors to Team Cohesion and Performance

NASA Technical Reports Server (NTRS)

Parke, Bonny; Orasanu, Judith

2012-01-01

Behaviors of individuals in teams both contribute to and are molded by team dynamics. How they do so has been the subject of much research. A method of portraying individuals' behaviors in teams, the Team Diagramming Method (TDM) is presented. Behaviors are rated by other team members on three important dimensions: positivity/negativity, dominant/submissive, and task-orientedness/expressiveness. A study of 5-person teams engaging in a 3-day moon simulation task demonstrated that measures of these perceived behaviors as well as the variances of these behaviors correlated with cohesion measures and performance. The method shows strengths and weaknesses of particular teams and, by comparison with high-performing teams, suggests interventions based on individual as well as team behaviors. The primary goal of this study was to determine the extent to which these team level variables, derived from all team members' rated behaviors, were associated with previous methods of measuring cohesion and with performance. A secondary goal was to determine the stability of TDM measures over time by comparing team level variables based on ratings early and later in the team s work together.

Evaluation of a Physiologically Based Pharmacokinetic (PBPK) Model Used to Develop Health Protective Levels for Trichloroethylene

DTIC Science & Technology

2017-02-28

is the response variable resulting from an input parameter value of θ+. EPA (2011) used a variation of this equation to calculate their...EPA (2011) used both individual and grouped data. While individual data are preferred as it maintains any intra-individual variation , it is often...grouped data, the user would, ideally, account for the loss of intra-individual variation in some manner; however, there is not a commonly accepted

Gene Expression Signatures Characterized by Longitudinal Stability and Interindividual Variability Delineate Baseline Phenotypic Groups with Distinct Responses to Immune Stimulation.

PubMed

Scheid, Adam D; Van Keulen, Virginia P; Felts, Sara J; Neier, Steven C; Middha, Sumit; Nair, Asha A; Techentin, Robert W; Gilbert, Barry K; Jen, Jin; Neuhauser, Claudia; Zhang, Yuji; Pease, Larry R

2018-03-01

Human immunity exhibits remarkable heterogeneity among individuals, which engenders variable responses to immune perturbations in human populations. Population studies reveal that, in addition to interindividual heterogeneity, systemic immune signatures display longitudinal stability within individuals, and these signatures may reliably dictate how given individuals respond to immune perturbations. We hypothesize that analyzing relationships among these signatures at the population level may uncover baseline immune phenotypes that correspond with response outcomes to immune stimuli. To test this, we quantified global gene expression in peripheral blood CD4 + cells from healthy individuals at baseline and following CD3/CD28 stimulation at two time points 1 mo apart. Systemic CD4 + cell baseline and poststimulation molecular immune response signatures (MIRS) were defined by identifying genes expressed at levels that were stable between time points within individuals and differential among individuals in each state. Iterative differential gene expression analyses between all possible phenotypic groupings of at least three individuals using the baseline and stimulated MIRS gene sets revealed shared baseline and response phenotypic groupings, indicating the baseline MIRS contained determinants of immune responsiveness. Furthermore, significant numbers of shared phenotype-defining sets of determinants were identified in baseline data across independent healthy cohorts. Combining the cohorts and repeating the analyses resulted in identification of over 6000 baseline immune phenotypic groups, implying that the MIRS concept may be useful in many immune perturbation contexts. These findings demonstrate that patterns in complex gene expression variability can be used to define immune phenotypes and discover determinants of immune responsiveness. Copyright © 2018 by The American Association of Immunologists, Inc.

A formal and data-based comparison of measures of motor-equivalent covariation.

PubMed

Verrel, Julius

2011-09-15

Different analysis methods have been developed for assessing motor-equivalent organization of movement variability. In the uncontrolled manifold (UCM) method, the structure of variability is analyzed by comparing goal-equivalent and non-goal-equivalent variability components at the level of elemental variables (e.g., joint angles). In contrast, in the covariation by randomization (CR) approach, motor-equivalent organization is assessed by comparing variability at the task level between empirical and decorrelated surrogate data. UCM effects can be due to both covariation among elemental variables and selective channeling of variability to elemental variables with low task sensitivity ("individual variation"), suggesting a link between the UCM and CR method. However, the precise relationship between the notion of covariation in the two approaches has not been analyzed in detail yet. Analysis of empirical and simulated data from a study on manual pointing shows that in general the two approaches are not equivalent, but the respective covariation measures are highly correlated (ρ > 0.7) for two proposed definitions of covariation in the UCM context. For one-dimensional task spaces, a formal comparison is possible and in fact the two notions of covariation are equivalent. In situations in which individual variation does not contribute to UCM effects, for which necessary and sufficient conditions are derived, this entails the equivalence of the UCM and CR analysis. Implications for the interpretation of UCM effects are discussed. Copyright © 2011 Elsevier B.V. All rights reserved.

When confidence comes and goes: How variation in self-efficacy moderates stressor-strain relationships.

PubMed

Peng, Ann C; Schaubroeck, John M; Xie, Jia Lin

2015-07-01

Inconsistent published findings regarding a proposed buffering role of self-efficacy in stress coping led us to develop a model in which within-person variability in self-efficacy over time affects how individuals' mean levels of self-efficacy moderate the relationship between demands and psychological symptoms. Results from two independent samples (manufacturing workers and college students) supported the hypothesized interaction between demands, self-efficacy mean level, and self-efficacy variability. Demands were more positively associated with psychological strain among those with high and stable self-efficacy than those with high and variable self-efficacy. We discuss the implications of intrapersonal variability in self-efficacy for research on stress coping. (c) 2015 APA, all rights reserved).

Estimating degradation in real time and accelerated stability tests with random lot-to-lot variation: a simulation study.

PubMed

Magari, Robert T

2002-03-01

The effect of different lot-to-lot variability levels on the prediction of stability are studied based on two statistical models for estimating degradation in real time and accelerated stability tests. Lot-to-lot variability is considered as random in both models, and is attributed to two sources-variability at time zero, and variability of degradation rate. Real-time stability tests are modeled as a function of time while accelerated stability tests as a function of time and temperatures. Several data sets were simulated, and a maximum likelihood approach was used for estimation. The 95% confidence intervals for the degradation rate depend on the amount of lot-to-lot variability. When lot-to-lot degradation rate variability is relatively large (CV > or = 8%) the estimated confidence intervals do not represent the trend for individual lots. In such cases it is recommended to analyze each lot individually. Copyright 2002 Wiley-Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 91: 893-899, 2002

Trends in health complaints from 2002 to 2010 in 34 countries and their association with health behaviours and social context factors at individual and macro-level.

PubMed

Ottová-Jordan, Veronika; Smith, Otto R F; Augustine, Lilly; Gobina, Inese; Rathmann, Katharina; Torsheim, Torbjørn; Mazur, Joanna; Välimaa, Raili; Cavallo, Franco; Jericek Klanscek, Helena; Vollebergh, Wilma; Meilstrup, Charlotte; Richter, Matthias; Moor, Irene; Ravens-Sieberer, Ulrike

2015-04-01

This article describes trends and stability over time in health complaints in adolescents from 2002 to 2010 and investigates associations between health complaints, behavioural and social contextual factors at individual level and economic factors at macro-level. Comprising N = 510 876 11-, 13- and 15-year-old children and adolescents in Europe, North America and Israel, data came from three survey cycles of the international Health Behaviour in School-aged Children (HBSC) study. Age- and gender-adjusted trends in health complaints were examined in each country by means of linear regression. By using the country as the random effects variable, we tested to what extent individual and contextual variables were associated with health complaints. Significant associations are stronger for individual level determinants (e.g. being bullied, smoking) than for determinants at macro-level (e.g. GDP, Gini), as can be seen by the small effect sizes (less than 5% for different trends). Health complaints are fairly stable over time in most countries, and no clear international trend in health complaints can be observed between 2002 and 2010. The most prominent stable determinants were being female, being bullied, school pressure and smoking. Factors associated with health complaints are more related to the proximal environment than to distal macro-level factors. This points towards intensifying targeted interventions, (e.g. for bullying) and also targeting specific risk groups. The comparably small effect size at country-level indicates that country-level factors have an impact on health and should not be ignored. © The Author 2015. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

Associations between race, sex and immune response variations to rubella vaccination in two independent cohorts

PubMed Central

Haralambieva, Iana H.; Salk, Hannah M.; Lambert, Nathaniel D.; Ovsyannikova, Inna G.; Kennedy, Richard B.; Warner, Nathaniel D.; Pankratz, V.Shane; Poland, Gregory A.

2014-01-01

Introduction Immune response variations after vaccination are influenced by host genetic factors and demographic variables, such as race, ethnicity and sex. The latter have not been systematically studied in regard to live rubella vaccine, but are of interest for developing next generation vaccines for diverse populations, for predicting immune responses after vaccination, and for better understanding the variables that impact immune response. Methods We assessed associations between demographic variables, including race, ethnicity and sex, and rubella-specific neutralizing antibody levels and secreted cytokines (IFN! , IL-6) in two independent cohorts (1,994 subjects), using linear and linear mixed models approaches, and genetically defined racial and ethnic categorizations. Results Our replicated findings in two independent, large, racially diverse cohorts indicate that individuals of African descent have significantly higher rubella-specific neutralizing antibody levels compared to individuals of European descent and/or Hispanic ethnicity (p! 0.001). Conclusion Our study provides consistent evidence for racial/ethnic differences in humoral immune response following rubella vaccination. PMID:24530932

Chronotype correlates with developmental index, intelligence and academic achievement: A study based on nationwide indicators.

PubMed

Randler, Christoph

2017-01-01

Chronotype or morningness-eveningness (M/E) is an individual trait with a biological basis. In this study, I analysed the relationship between M/E and nationwide available data, such as economic variables, school achievement, intelligence and conscientiousness, which is a personality trait. These variables have been chosen because, first, they are linked on the individual level with circadian preference, and, second these associations have been found based on meta-analyses, which gives these findings a high plausibility. In addition, economic status has also been proposed to be related to M/E. Higher developed countries showed a lower morningness, based on both, the ranking of countries as well as on the HDI value. Similarly, GNI was related to morningness, while higher intelligence and performance in PISA were related to eveningness. Conscientiousness was related to morningness, although the results failed the significance level marginally. When using IQ as a control variable in partial correlations, the relationship between GNI and morningness disappeared, as did the correlation between eveningness and PISA results.

Aflatoxin variability in pistachios.

PubMed Central

Mahoney, N E; Rodriguez, S B

1996-01-01

Pistachio fruit components, including hulls (mesocarps and epicarps), seed coats (testas), and kernels (seeds), all contribute to variable aflatoxin content in pistachios. Fresh pistachio kernels were individually inoculated with Aspergillus flavus and incubated 7 or 10 days. Hulled, shelled kernels were either left intact or wounded prior to inoculation. Wounded kernels, with or without the seed coat, were readily colonized by A. flavus and after 10 days of incubation contained 37 times more aflatoxin than similarly treated unwounded kernels. The aflatoxin levels in the individual wounded pistachios were highly variable. Neither fungal colonization nor aflatoxin was detected in intact kernels without seed coats. Intact kernels with seed coats had limited fungal colonization and low aflatoxin concentrations compared with their wounded counterparts. Despite substantial fungal colonization of wounded hulls, aflatoxin was not detected in hulls. Aflatoxin levels were significantly lower in wounded kernels with hulls than in kernels of hulled pistachios. Both the seed coat and a water-soluble extract of hulls suppressed aflatoxin production by A. flavus. PMID:8919781

Capturing Moment-To-Moment Changes in Multivariate Human Experience

ERIC Educational Resources Information Center

De Ruiter, Naomi M. P.; Van Der Steen, Steffie; Den Hartigh, Ruud J. R.; Van Geert, Paul L. C.

2017-01-01

In this article, we aim to shed light on a technique to study intra-individual variability that spans the time frame of seconds and minutes, i.e., micro-level development. This form of variability is omnipresent in behavioural development and processes of human experience, yet is often ignored in empirical studies, given a lack of proper analysis…

Can individual cognitions, self-regulation and environmental variables explain educational differences in vegetable consumption?: a cross-sectional study among Dutch adults.

PubMed

Springvloet, Linda; Lechner, Lilian; Oenema, Anke

2014-12-06

Educational differences in health-related behaviors, where low- and moderate-educated individuals have poorer outcomes than high-educated individuals, are persistent. The reasons for these differences remain poorly understood. This study explored whether individual cognitions, self-regulation and environmental-level factors may explain educational differences in vegetable consumption. A cross-sectional study was conducted among 1,342 Dutch adults, of whom 54.5% were low/moderate-educated. Individuals completed an online questionnaire, assessing education, vegetable consumption, demographics, individual cognitions (attitude towards consuming 200 grams of vegetables a day, self-efficacy, subjective norm, intention, perception of vegetables as being expensive), self-regulation (general self-regulation, vegetable-specific action- and coping planning) and environmental-level factors (perception of availability of vegetables in the supermarket and availability of vegetables at home). The joint-significance test was used to determine significant mediation effects. Low/moderate-educated individuals consumed less vegetables (M = 151.2) than high-educated individuals (M = 168.1, β = -0.15, P < .001). Attitude and availability of vegetables at home were found to partially mediate the association between education and vegetable consumption (percentage mediated effect: 24.46%). Since attitude and availability of vegetables at home partially explain the difference in vegetable consumption between low/moderate- and high-educated individuals, these variables may be good target points for interventions to promote vegetable consumption among low/moderate-educated individuals.

Direct and moderating effects of community context on the psychological well-being of African American women.

PubMed

Cutrona, C E; Russell, D W; Hessling, R M; Brown, P A; Murry, V

2000-12-01

The effects of community characteristics on well-being were examined among 709 African American women. Direct and moderating effects of neighborhood characteristics on distress were tested. Aggregate-level ratings of neighborhood cohesion and disorder were significantly related to distress, although the relation between cohesion and distress became nonsignificant when individual risk factors were statistically controlled. Aggregate-level neighborhood variables interacted significantly with individual risk and resource variables in the prediction of distress, consistent with trait-situation interaction theories (D. Magnusson & N. S. Endler, 1977). Community cohesion intensified the benefits of a positive life outlook. Community disorder intensified both the benefits of personal resources and the detrimental effects of personal risk factors. Results showed evidence of resilience among African American women.

Direct and Moderating Effects of Community Context on the Psychological Well-Being of African American Women

PubMed Central

Cutrona, Carolyn E.; Russell, Daniel W.; Hessling, Robert M.; Brown, P. Adama; Murry, Velma

2007-01-01

The effects of community characteristics on well-being were examined among 709 African American women. Direct and moderating effects of neighborhood characteristics on distress were tested. Aggregate-level ratings of neighborhood cohesion and disorder were significantly related to distress, although the relation between cohesion and distress became nonsignificant when individual risk factors were statistically controlled. Aggregate-level neighborhood variables interacted significantly with individual risk and resource variables in the prediction of distress, consistent with trait-situation interaction theories (D. Magnusson & N. S. Endler, 1977). Community cohesion intensified the benefits of a positive life outlook. Community disorder intensified both the benefits of personal resources and the detrimental effects of personal risk factors. Results showed evidence of resilience among African American women. PMID:11138756

Affective Balance, Team Prosocial Efficacy and Team Trust: A Multilevel Analysis of Prosocial Behavior in Small Groups.

PubMed

Cuadrado, Esther; Tabernero, Carmen

2015-01-01

Little research has focused on how individual- and team-level characteristics jointly influence, via interaction, how prosocially individuals behave in teams and few studies have considered the potential influence of team context on prosocial behavior. Using a multilevel perspective, we examined the relationships between individual (affective balance) and group (team prosocial efficacy and team trust) level variables and prosocial behavior towards team members. The participants were 123 students nested in 45 small teams. A series of multilevel random models was estimated using hierarchical linear and nonlinear modeling. Individuals were more likely to behave prosocially towards in-group members when they were feeling good. Furthermore, the relationship between positive affective balance and prosocial behavior was stronger in teams with higher team prosocial efficacy levels as well as in teams with higher team trust levels. Finally, the relevance of team trust had a stronger influence on behavior than team prosocial efficacy.

Controlled assessment of the efficacy of occlusal stabilization splints on sleep bruxism.

PubMed

van der Zaag, Jacques; Lobbezoo, Frank; Wicks, Darrel J; Visscher, Corine M; Hamburger, Hans L; Naeije, Machiel

2005-01-01

To assess the efficacy of occlusal stabilization splints in the management of sleep bruxism (SB) in a double-blind, parallel, controlled, randomized clinical trial. Twenty-one participants were randomly assigned to an occlusal splint group (n = 11; mean age = 34.2 +/- 13.1 years) or a palatal splint (ie, an acrylic palatal coverage) group (n = 10; mean age = 34.9 +/- 11.2 years). Two polysomnographic recordings that included bilateral masseter electromyographic activity were made: one prior to treatment, the other after a treatment period of 4 weeks. The number of bruxism episodes per hour of sleep (Epi/h), the number of bursts per hour (Bur/h), and the bruxism time index (ie, the percentage of total sleep time spent bruxing) were established as outcome variables at a 10% maximum voluntary contraction threshold level. A general linear model was used to test both the effects between splint groups and within the treatment phase as well as their interaction for each outcome variable. Neither occlusal stabilization splints nor palatal splints had an influence on the SB outcome variables or on the sleep variables measured on a group level. In individual cases, variable outcomes were found: Some patients had an increase (33% to 48% of the cases), while others showed no change (33% to 48%) or a decrease (19% to 29%) in SB outcome variables. The absence of significant group effects of splints in the management of SB indicates that caution is required when splints are indicated, apart from their role in the protection against dental wear. The application of splints should therefore be considered at the individual patient level.

Two distinct, geographically overlapping lineages of the corallimorpharian Ricordea florida (Cnidaria: Hexacorallia: Ricordeidae)

NASA Astrophysics Data System (ADS)

Torres-Pratts, H.; Lado-Insua, T.; Rhyne, A. L.; Rodríguez-Matos, L.; Schizas, N. V.

2011-06-01

We examined the genetic variation of the corallimorpharian Ricordea florida; it is distributed throughout the Caribbean region and is heavily harvested for the marine aquarium trade. Eighty-four distinct individuals of R. florida were sequenced from four geographically distant Caribbean locations (Curaçao, Florida, Guadeloupe, and Puerto Rico). Analysis of the ribosomal nuclear region (ITS1, 5.8S, ITS2) uncovered two geographically partially overlapping genetic lineages in R. florida, probably representing two cryptic species. Lineage 1 was found in Florida and Puerto Rico, and Lineage 2 was found in Florida, Puerto Rico, Guadeloupe, and Curaçao. Because of the multi-allelic nature of the ITS region, four individuals from Lineage 1 and six from Lineage 2 were cloned to evaluate the levels of hidden intra-individual variability. Pairwise genetic comparisons indicated that the levels of intra-individual and intra-lineage variability (<1%) were approximately an order of magnitude lower than the divergence (~9%) observed between the two lineages. The fishery regulations of the aquarium trade regard R. florida as one species. More refined regulations should take into account the presence of two genetic lineages, and they should be managed separately in order to preserve the long-term evolutionary potential of this corallimorpharian. The discovery of two distinct lineages in R. florida illustrates the importance of evaluating genetic variability in harvested species prior to the implementation of management policies.

Does a geographical context of deprivation affect differences in injury mortality? A multilevel analysis in South Korean adults residing in metropolitan cities.

PubMed

Lee, JeSuk; Lee, Weon-Young; Noh, Maengseok; Khang, Young-Ho

2014-05-01

This study aimed to examine whether the socioeconomic context of urban areas affects differences in adult mortality from injuries in the districts of all seven South Korean metropolitan cities, after adjusting for individual demographic and socioeconomic indicators. Two different sets of data were used in this study: (1) the National Death Registration data from 2003 to 2008; and (2) the National Census in 2005. Variables for individual characteristics were gender, age, residential area and educational level. A geographic deprivation index was calculated based on the Carstairs Index. Multilevel Poisson regression models were used to analyse the relationship between area deprivation levels and injury mortality. Greater mortality risks of traffic accidents, falls, suicide and all injuries were found in the elderly, the less educated and men, compared with their counterparts. The most deprived districts were at greater risks of death due to traffic accidents (risk ratio (RR)=1.34; 95% CI 1.05 to 1.73), falls (RR=1.63; 95% CI 1.20 to 2.20), suicide (RR=1.09; 95% CI 1.01 to 1.17) and all injuries (RR=1.14; 95% CI 1.07 to 1.22) compared with the least deprived districts, even after individual level socioeconomic variables were controlled for. However, area level deprivation did not show cross level interactions with the individual level education in estimating fatal injury risks. Both contextual and compositional effects of socioeconomic status on injury mortality among urban areas in South Korea should be considered in allocating resources for injury prevention.

Effects of individual quality, reproductive success and environmental variability on survival of a long-lived seabird.

PubMed

Lescroël, Amélie; Dugger, Katie M; Ballard, Grant; Ainley, David G

2009-07-01

1. Heterogeneity in individual quality (i.e. individuals having different performance levels that are consistent throughout life) can drive the demography of iteroparous species, but quality in the context of environmental variability has rarely been evaluated. 2. We investigated the demographic responses of a long-lived seabird, the Adélie penguin (Pygoscelis adeliae), to contrasting environmental conditions as a function of reproductive success, breeding quality (BQ) and experience. A continuous index of BQ (BQI) was developed to reflect an individual's ability, relative to others, to produce viable offspring. 3. First, we assessed the relative importance of costs of reproduction vs. heterogeneity in quality by comparing survival and reproductive probabilities among deferred, successful and unsuccessful breeders under 'demanding' conditions using multistate capture-mark-recapture modelling. Then, we quantified the influence of BQI on adult survival among experienced breeders vs. the whole study population under both 'normal' and 'demanding' conditions. 4. Higher survival rates were exhibited by successful (74-76%) compared to unsuccessful breeders (64%); the former also more frequently reproduced successfully at year t + 1. 5. From 1997 to 2006, adult survival ranged from 64-79%, with BQI accounting for 91% of variability in the entire study population, but only 17% in experienced breeders. The weakened relationship between BQI and survival in experienced breeders supports the theory that selection during the first reproductive event accounts for a more homogeneous pool of experienced breeders. 6. No significant effect of environmental covariates on survival was evident, suggesting that what appeared to be demanding conditions were within the range that could be buffered by this species. 7. For the first time in seabirds, a quadratic relationship between adult survival and BQI showed that adult survival is shaped by both heterogeneity in quality and reproductive costs. Our study confirms that population demographic patterns are affected by factors at the individuals' level (e.g., individual quality) that are obscured at population-scale levels.

Risk factors in the development of behaviour difficulties among students with special educational needs and disabilities: A multilevel analysis.

PubMed

Oldfield, Jeremy; Humphrey, Neil; Hebron, Judith

2017-06-01

Students with special educational needs and disabilities (SEND) are more likely to exhibit behaviour difficulties than their typically developing peers. The aim of this study was to identify specific risk factors that influence variability in behaviour difficulties among individuals with SEND. The study sample comprised 4,228 students with SEND, aged 5-15, drawn from 305 primary and secondary schools across England. Explanatory variables were measured at the individual and school levels at baseline, along with a teacher-reported measure of behaviour difficulties (assessed at baseline and at 18-month follow-up). Hierarchical linear modelling of data revealed that differences between schools accounted for between 13% (secondary) and 15.4% (primary) of the total variance in the development of students' behaviour difficulties, with the remainder attributable to individual differences. Statistically significant risk markers for these problems across both phases of education were being male, eligibility for free school meals, being identified as a bully, and lower academic achievement. Additional risk markers specific to each phase of education at the individual and school levels are also acknowledged. Behaviour difficulties are affected by risks across multiple ecological levels. Addressing any one of these potential influences is therefore likely to contribute to the reduction in the problems displayed. © 2017 The British Psychological Society.

Blood pressure (BP) assessment-from BP level to BP variability.

PubMed

Feber, Janusz; Litwin, Mieczyslaw

2016-07-01

The assessment of blood pressure (BP) can be challenging in children, especially in very young individuals, due to their variable body size and lack of cooperation. In the absence of data relating BP with cardiovascular outcomes in children, there is a need to convert absolute BP values (in mmHg) into age-, gender- and height appropriate BP percentiles or Z-scores in order to compare a patient's BP with the BP of healthy children of the same age, but also of children of different ages. Traditionally, the interpretation of BP has been based mainly on the assessment of the BP level obtained by office, home or 24-h BP monitoring. Recent studies suggest that it is not only BP level (i.e. average BP) but also BP variability that is clinically important for the development of target organ damage, including the progression of chronic kidney disease. In this review we describe current methods to evaluate of BP level, outline available methods for BP variability assessment and discuss the clinical consequences of BP variability, including its potential role in the management of hypertension.

Systemic Exposure to Thiopurines and Risk of Relapse in Children with Acute Lymphoblastic Leukemia: A Children’s Oncology Group Study

PubMed Central

Bhatia, Smita; Landier, Wendy; Hageman, Lindsey; Chen, Yanjun; Kim, Heeyoung; Sun, Can-Lan; Kornegay, Nancy; Evans, William E; Angiolillo, Anne L; Bostrom, Bruce; Casillas, Jacqueline; Lew, Glen; Maloney, Kelly W; Mascarenhas, Leo; Ritchey, A. Kim; Termuhlen, Amanda M; Carroll, William L; Wong, F Lennie; Relling, Mary V

2015-01-01

Importance Variability in prescribed 6-mercaptopurine and lack of adherence to 6-mercaptopurine could result in intra-individual variability in systemic exposure to 6-mercaptopurine (measured as erythrocyte thioguanine nucleotide levels) in children with acute lymphoblastic leukemia. The impact of intra-individual variability in systemic exposure to 6-mercaptopurine on relapse risk is unknown. Objective To determine impact of high intra-individual variability in 6-mercaptopurine systemic exposure on relapse risk in children with acute lymphoblastic leukemia. Design Prospective longitudinal design; daily adherence monitoring, 6-mercaptopurine dose-intensity and erythrocyte thioguanine nucleotide levels (pmol/8*10^8 erythrocytes) measured for 6 consecutive months per patient; cohort followed for a median of 6.7 years from diagnosis. Setting Children’s Oncology Group study (COG-AALL03N1); 94 participating institutions; ambulatory care setting. Participants Participants included 742 children meeting the following eligibility criteria: diagnosis of acute lymphoblastic leukemia at ≤21 years; in first continuous remission at study entry; receiving self/parent/caregiver-administered oral 6-mercaptopurine during maintenance. Median age at diagnosis: 5 years; 68% were male; 43% with NCI-based high-risk disease. Main Outcome Measures Adherence measured electronically using Medication Event Monitoring System that recorded date/time of each 6-mercaptopurine bottle opening; adherence rate defined as ratio of days of 6-mercaptopurine bottle opened to days when 6-mercaptopurine prescribed. 6-mercaptopurine doses actually prescribed were divided by planned protocol doses (75mg/m2/day) to compute average monthly dose-intensity. Electronically-monitored adherence (68,716 person-days), 6-mercaptopurine dose-intensity (120,439 person-days) and monthly erythrocyte thioguanine nucleotide levels (n=3,944 measurements) contributed to the analysis. Using intra-individual coefficients of variation (CV %), patients were classified as having stable (CV % <85th percentile) vs. varying (CV % ≥85th percentile) indices. Results Adjusting for clinical prognosticators, patients with 6-mercaptopurine non-adherence (mean adherence rate <95%) were at a 2.7 fold increased risk of relapse (95% confidence interval [CI], 1.3 to 5.6, p=0.01). Among adherers, high intra-individual variability in thioguanine nucleotide levels contributes to increased relapse risk (HR=4.4, 95% CI, 1.2 to 15.7, p=0.02). Furthermore, adherers with varying thioguanine nucleotide levels had varying 6-mercaptopurine dose-intensity (OR=4.5, p=0.006) and 6-mercaptopurine drug interruptions (OR=10.2, p=0.003). Conclusions and Relevance These findings emphasize the need to maximize 6-mercaptopurine adherence and maintain steady thiopurine exposure to minimize relapse in children with acute lymphoblastic leukemia. PMID:26181173

Examining the lag time between state-level income inequality and individual disabilities: a multilevel analysis.

PubMed

Gadalla, Tahany M; Fuller-Thomson, Esme

2008-12-01

State-level income inequality has been found to have an effect on individual health outcomes, even when controlled for important individual-level variables such as income, education, age, and gender. The effect of income inequality on health may not be immediate and may, in fact, have a substantial lag time between exposure to inequality and eventual health outcome. We used the 2006 American Community Survey to examine the association of state-level income inequality and 2 types of physical disabilities. We used 6 different lag times, ranging between 0 and 25 years, on the total sample and on those who resided in their state of birth. Income inequality in 1986 had the strongest correlation with 2006 disability levels. Odds ratios were consistently 10% higher for those born in the same state compared with the total population.

An association between neighbourhood wealth inequality and HIV prevalence in sub-Saharan Africa.

PubMed

Brodish, Paul Henry

2015-05-01

This paper investigates whether community-level wealth inequality predicts HIV serostatus using DHS household survey and HIV biomarker data for men and women ages 15-59 pooled from six sub-Saharan African countries with HIV prevalence rates exceeding 5%. The analysis relates the binary dependent variable HIV-positive serostatus and two weighted aggregate predictors generated from the DHS Wealth Index: the Gini coefficient, and the ratio of the wealth of households in the top 20% wealth quintile to that of those in the bottom 20%. In separate multilevel logistic regression models, wealth inequality is used to predict HIV prevalence within each statistical enumeration area, controlling for known individual-level demographic predictors of HIV serostatus. Potential individual-level sexual behaviour mediating variables are added to assess attenuation, and ordered logit models investigate whether the effect is mediated through extramarital sexual partnerships. Both the cluster-level wealth Gini coefficient and wealth ratio significantly predict positive HIV serostatus: a 1 point increase in the cluster-level Gini coefficient and in the cluster-level wealth ratio is associated with a 2.35 and 1.3 times increased likelihood of being HIV positive, respectively, controlling for individual-level demographic predictors, and associations are stronger in models including only males. Adding sexual behaviour variables attenuates the effects of both inequality measures. Reporting eleven plus lifetime sexual partners increases the odds of being HIV positive over five-fold. The likelihood of having more extramarital partners is significantly higher in clusters with greater wealth inequality measured by the wealth ratio. Disaggregating logit models by sex indicates important risk behaviour differences. Household wealth inequality within DHS clusters predicts HIV serostatus, and the relationship is partially mediated by more extramarital partners. These results emphasize the importance of incorporating higher-level contextual factors, investigating behavioural mediators, and disaggregating by sex in assessing HIV risk in order to uncover potential mechanisms of action and points of preventive intervention.

An association between neighborhood wealth inequality and HIV prevalence in sub-Saharan Africa

PubMed Central

Brodish, Paul Henry

2016-01-01

Summary This paper investigates whether community-level wealth inequality predicts HIV serostatus, using DHS household survey and HIV biomarker data for men and women ages 15-59 pooled from six sub-Saharan African countries with HIV prevalence rates exceeding five percent. The analysis relates the binary dependent variable HIV positive serostatus and two weighted aggregate predictors generated from the DHS Wealth Index: the Gini coefficient, and the ratio of the wealth of households in the top 20% wealth quintile to that of those in the bottom 20%. In separate multilevel logistic regression models, wealth inequality is used to predict HIV prevalence within each SEA, controlling for known individual-level demographic predictors of HIV serostatus. Potential individual-level sexual behavior mediating variables are added to assess attenuation, and ordered logit models investigate whether the effect is mediated through extramarital sexual partnerships. Both the cluster-level wealth Gini coefficient and wealth ratio significantly predict positive HIV serostatus: a 1 point increase in the cluster-level Gini coefficient and in the cluster-level wealth ratio is associated with a 2.35 and 1.3 times increased likelihood of being HIV positive, respectively, controlling for individual-level demographic predictors, and associations are stronger in models including only males. Adding sexual behavior variables attenuates the effects of both inequality measures. Reporting 11 plus lifetime sexual partners increases the odds of being HIV positive over five-fold. The likelihood of having more extramarital partners is significantly higher in clusters with greater wealth inequality measured by the wealth ratio. Disaggregating logit models by sex indicates important risk behavior differences. Household wealth inequality within DHS clusters predicts HIV serostatus, and the relationship is partially mediated by more extramarital partners. These results emphasize the importance of incorporating higher-level contextual factors, investigating behavioral mediators, and disaggregating by sex in assessing HIV risk in order to uncover potential mechanisms of action and points of preventive intervention PMID:24406021

Intercellular Variability in Protein Levels from Stochastic Expression and Noisy Cell Cycle Processes

PubMed Central

Soltani, Mohammad; Vargas-Garcia, Cesar A.; Antunes, Duarte; Singh, Abhyudai

2016-01-01

Inside individual cells, expression of genes is inherently stochastic and manifests as cell-to-cell variability or noise in protein copy numbers. Since proteins half-lives can be comparable to the cell-cycle length, randomness in cell-division times generates additional intercellular variability in protein levels. Moreover, as many mRNA/protein species are expressed at low-copy numbers, errors incurred in partitioning of molecules between two daughter cells are significant. We derive analytical formulas for the total noise in protein levels when the cell-cycle duration follows a general class of probability distributions. Using a novel hybrid approach the total noise is decomposed into components arising from i) stochastic expression; ii) partitioning errors at the time of cell division and iii) random cell-division events. These formulas reveal that random cell-division times not only generate additional extrinsic noise, but also critically affect the mean protein copy numbers and intrinsic noise components. Counter intuitively, in some parameter regimes, noise in protein levels can decrease as cell-division times become more stochastic. Computations are extended to consider genome duplication, where transcription rate is increased at a random point in the cell cycle. We systematically investigate how the timing of genome duplication influences different protein noise components. Intriguingly, results show that noise contribution from stochastic expression is minimized at an optimal genome-duplication time. Our theoretical results motivate new experimental methods for decomposing protein noise levels from synchronized and asynchronized single-cell expression data. Characterizing the contributions of individual noise mechanisms will lead to precise estimates of gene expression parameters and techniques for altering stochasticity to change phenotype of individual cells. PMID:27536771

Socioeconomic-status and mental health in a personality disorder sample: The importance of neighbourhood factors

PubMed Central

Walsh, Zach; Shea, M. Tracie; Yen, Shirley; Ansell, Emily B.; Grilo, Carlos M.; McGlashan, Thomas H.; Stout, Robert L.; Bender, Donna S.; Skodol, Andrew E.; Sanislow, Charles A.; Morey, Lesley C.; Gunderson, John G.

2015-01-01

This cross-sectional study examined the associations between neighbourhood-level socioeconomic-status, and psychosocial functioning and personality pathology among 335 adults drawn from the Collaborative Longitudinal Personality Disorders Study. Participants belonged to four personality disorder (PD) diagnostic groups: Avoidant, Borderline, Schizotypal, and Obsessive Compulsive. Global functioning, social adjustment, and PD symptoms were assessed following a minimum two-year period of residential stability. Residence in higher-risk neighbourhoods was associated with more PD symptoms and lower levels of functioning and social adjustment. These relationships were consistent after controlling for individual-level socioeconomic-status and ethnicity; however, the positive association between neighbourhood-level socio-economic risk and PD symptoms was evident only at higher levels of individual-level socio-economic risk. Our findings identify NSES as a candidate for explaining some of the variability in symptoms and functioning among PD individuals. PMID:22984860

Comparison of propranolol and metoprolol in the management of hyperthyroidism.

PubMed

Murchison, L E; How, J; Bewsher, P D

1979-12-01

1 Propranolol and metoprolol were both effective in controlling the symptoms and signs of hyperthyroidism. 2 Propranolol caused a highly significant increase in serum reverse T3 concentrations with lesser changes in other serum thyroid hormone levels, whereas metoprolol did not have this effect. 3 Steady-state plasma propranolol and metoprolol levels showed marked inter-individual variation. Metoprolol concentrations showed relatively little intra-individual variability, and could be related to the clinical efficacy of the drug, whereas no such relationship was demonstrated for propranolol.

Factors influencing acceptance of disability in individuals with spinal cord injury in Neiva, Colombia, South America.

PubMed

Nicholls, Elizabeth; Lehan, Tara; Plaza, Silvia Leonor Olivera; Deng, Xiaoyan; Romero, Jose Libardo Perdomo; Pizarro, Jose Anselmo Arango; Carlos Arango-Lasprilla, Juan

2012-01-01

The aim of the present study was to determine the level of acceptance of disability as measured by the Acceptance of Disability Scale (ADS) within a sample of individuals with spinal cord injury (SCI) from Neiva, Colombia and to examine the influence of sociodemographic variables, injury characteristics, and level of depression on ADS score. The ADS was administered to 40 adults with SCI from Nieva, Colombia who were recruited from an organization that connects individuals with disabilities to resources. Most (92.5%) participants were men, with a mean age of 34.75 years and approximately 12 years since injury. Fifty-five percent of subjects were diagnosed with paraplegia and the remainder with tetraplegia. Descriptive, linear model and multiple regression analyses were used to describe the relationship between the independent and dependent variables. The mean total ADS score of this sample was 171.5, indicating overall low disability acceptance. After controlling for level of depression and time since injury, gender was significantly related to ADS score such that women reported higher acceptance of disability. After controlling for gender and time since injury, level of depression was significantly related to ADS score. Acceptance of disability is a serious problem in this group of SCI survivors in Neiva, Colombia, especially among women and individuals with higher levels of depression. Because acceptance of disability is likely a problem for many individuals living with disability in the developing world, future researchers should investigate what interventions (e.g. counseling, pharmacological intervention, social service programs) can be implemented to improve acceptance of disability in this population. © 2012 Informa UK, Ltd.

Organization of care and diagnosed depression among women veterans.

PubMed

Sambamoorthi, Usha; Bean-Mayberry, Bevanne; Findley, Patricia A; Yano, Elizabeth M; Banerjea, Ranjana

2010-09-01

To analyze the association between the organizational features of integration of physical and mental healthcare in womens health clinics and the diagnosis of depression among women veterans with or at risk for cardiovascular conditions (ie, diabetes mellitus, heart disease, or hypertension). Retrospective and observational secondary data analyses. We studied 27,972 women veterans from 118 facilities with diagnosed cardiovascular conditions in fiscal year 2001 (FY2001) using merged Medicare claims and Veterans Health Administration (VHA) data merged with the 1999 VHA Survey of Primary Care Practices and the 2001 VHA Survey of Women Veterans Health Programs and Practices. The dependent variable was a binary indicator for diagnosed depression during FY2001 at the individual level. We used a multilevel logistic regression model to control for clustering of women veterans within facilities. Individual-level independent variables included demographics, socioeconomic characteristics, and chronic physical conditions. Overall, 27% of women veterans using the VHA were diagnosed as having depression in FY2001. Across facilities, rates of diagnosed depression varied from 13% to 41%. After controlling for individual-level and facility-level independent variables, women veterans who were served in separate women's health clinics with integrated physical and mental healthcare were more likely to have diagnosed depression. The adjusted odds ratio was 1.12 (95% confidence interval, 1.01-1.25). Existing women-specific VHA organizational features with integration of primary care and mental health seem effective in diagnosing depression. Emerging patient-centered medical home models may facilitate diagnosis and treatment of mental health issues among women with complex chronic conditions.

Untangling the Influences of Voluntary Running, Environmental Complexity, Social Housing and Stress on Adult Hippocampal Neurogenesis

PubMed Central

Grégoire, Catherine-Alexandra; Bonenfant, David; Le Nguyen, Adalie; Aumont, Anne; Fernandes, Karl J. L.

2014-01-01

Environmental enrichment (EE) exerts powerful effects on brain physiology, and is widely used as an experimental and therapeutic tool. Typical EE paradigms are multifactorial, incorporating elements of physical exercise, environmental complexity, social interactions and stress, however the specific contributions of these variables have not been separable using conventional housing paradigms. Here, we evaluated the impacts of these individual variables on adult hippocampal neurogenesis by using a novel “Alternating EE” paradigm. For 4 weeks, adult male CD1 mice were alternated daily between two enriched environments; by comparing groups that differed in one of their two environments, the individual and combinatorial effects of EE variables could be resolved. The Alternating EE paradigm revealed that (1) voluntary running for 3 days/week was sufficient to increase both mitotic and post-mitotic stages of hippocampal neurogenesis, confirming the central importance of exercise; (2) a complex environment (comprised of both social interactions and rotated inanimate objects) had no effect on neurogenesis itself, but enhanced depolarization-induced c-Fos expression (attributable to social interactions) and buffered stress-induced plasma corticosterone levels (attributable to inanimate objects); and (3) neither social isolation, group housing, nor chronically increased levels of plasma corticosterone had a prolonged impact on neurogenesis. Mouse strain, handling and type of running apparatus were tested and excluded as potential confounding factors. These findings provide valuable insights into the relative effects of key EE variables on adult neurogenesis, and this “Alternating EE” paradigm represents a useful tool for exploring the contributions of individual EE variables to mechanisms of neural plasticity. PMID:24465980

Synthesizing trait correlations and functional relationships across multiple scales: A Hierarchical Bayes approach

NASA Astrophysics Data System (ADS)

Shiklomanov, A. N.; Cowdery, E.; Dietze, M.

2016-12-01

Recent syntheses of global trait databases have revealed that although the functional diversity among plant species is immense, this diversity is constrained by trade-offs between plant strategies. However, the use of among-trait and trait-environment correlations at the global scale for both qualitative ecological inference and land surface modeling has several important caveats. An alternative approach is to preserve the existing PFT-based model structure while using statistical analyses to account for uncertainty and variability in model parameters. In this study, we used a hierarchical Bayesian model of foliar traits in the TRY database to test the following hypotheses: (1) Leveraging the covariance between foliar traits will significantly constrain our uncertainty in their distributions; and (2) Among-trait covariance patterns are significantly different among and within PFTs, reflecting differences in trade-offs associated with biome-level evolution, site-level community assembly, and individual-level ecophysiological acclimation. We found that among-trait covariance significantly constrained estimates of trait means, and the additional information provided by across-PFT covariance led to more constraint still, especially for traits and PFTs with low sample sizes. We also found that among-trait correlations were highly variable among PFTs, and were generally inconsistent with correlations within PFTs. The hierarchical multivariate framework developed in our study can readily be enhanced with additional levels of hierarchy to account for geographic, species, and individual-level variability.

The influence of gender equality policies on gender inequalities in health in Europe.

PubMed

Palència, Laia; Malmusi, Davide; De Moortel, Deborah; Artazcoz, Lucía; Backhans, Mona; Vanroelen, Christophe; Borrell, Carme

2014-09-01

Few studies have addressed the effect of gender policies on women's health and gender inequalities in health. This study aims to analyse the relationship between the orientation of public gender equality policies and gender inequalities in health in European countries, and whether this relationship is mediated by gender equality at country level or by other individual social determinants of health. A multilevel cross-sectional study was performed using individual-level data extracted from the European Social Survey 2010. The study sample consisted of 23,782 men and 28,655 women from 26 European countries. The dependent variable was self-perceived health. Individual independent variables were gender, age, immigrant status, educational level, partner status and employment status. The main contextual independent variable was a modification of Korpi's typology of family policy models (Dual-earner, Traditional-Central, Traditional-Southern, Market-oriented and Contradictory). Other contextual variables were the Gender Empowerment Measure (GEM), to measure country-level gender equality, and the Gross Domestic Product (GDP). For each country and country typology the prevalence of fair/poor health by gender was calculated and prevalence ratios (PR, women compared to men) and 95% confidence intervals (CI) were computed. Multilevel robust Poisson regression models were fitted. Women had poorer self-perceived health than men in countries with traditional family policies (PR = 1.13, 95%CI: 1.07-1.21 in Traditional-Central and PR = 1.27, 95%CI: 1.19-1.35 in Traditional-Southern) and in Contradictory countries (PR = 1.08, 95%CI: 1.05-1.11). In multilevel models, only gender inequalities in Traditional-Southern countries were significantly higher than those in Dual-earner countries. Gender inequalities in self-perceived health were higher, women reporting worse self-perceived health than men, in countries with family policies that were less oriented to gender equality (especially in the Traditional-Southern country-group). This was partially explained by gender inequalities in the individual social determinants of health but not by GEM or GDP. Copyright © 2014 Elsevier Ltd. All rights reserved.

A Bayesian Approach for Analyzing Longitudinal Structural Equation Models

ERIC Educational Resources Information Center

Song, Xin-Yuan; Lu, Zhao-Hua; Hser, Yih-Ing; Lee, Sik-Yum

2011-01-01

This article considers a Bayesian approach for analyzing a longitudinal 2-level nonlinear structural equation model with covariates, and mixed continuous and ordered categorical variables. The first-level model is formulated for measures taken at each time point nested within individuals for investigating their characteristics that are dynamically…

Using Disability Models to Rethink Bullying in Schools

ERIC Educational Resources Information Center

Duncan, Neil

2013-01-01

Much research on bullying in schools positions individual children within a deficit model of personal variables, categorising and cataloguing them with high levels of aggressiveness, low levels of empathy and so on. While less than optimal school characteristics are sometimes noted, the expectation for change is on the children. This article…

Multilevel Effects of Student and Classroom Factors on Elementary Science Achievement in Five Countries

ERIC Educational Resources Information Center

Kaya, Sibel; Rice, Diana C.

2010-01-01

This study examined the effects of individual student factors and classroom factors on elementary science achievement within and across five countries. The student-level factors included gender, self-confidence in science and home resources. The classroom-level factors included teacher characteristics, instructional variables and classroom…

Serum and plasma brain-derived neurotrophic factor (BDNF) in abstinent alcoholics and social drinkers

PubMed Central

D’Sa, Carrol; Dileone, Ralph J.; Anderson, George M.; Sinha, Rajita

2013-01-01

Although the effects of alcohol on brain-derived neurotrophic factor (BDNF) have been extensively studied in rodents, BDNF levels have rarely been measured in abstinent, alcohol-dependent (AD) individuals. Interpretation of reported group comparisons of serum BDNF levels is difficult due to limited information regarding analytical variance, biological variability, and the relative contribution of platelet and plasma pools to serum BDNF. Analytical variance (intra- and inter-assay coefficients of variation) of the enzyme-linked immunosorbent assay (ELISA) was characterized. Within- and between-subject variability, and group differences in serum and plasma BDNF, was assessed on three separate days in 16, 4-week abstinent AD individuals (7M/9F) and 16 social drinkers (SDs; 8M/8F). Significantly higher mean (±sd) serum BDNF levels were observed for the AD group compared to the SD (p = 0.003). No significant difference in mean baseline plasma BDNF levels was observed between AD and SD groups. The low analytical variance, high day-to-day within-individual stability and the high degree of individuality demonstrates the potential clinical utility of measuring serum BDNF levels. The low correlations that we observed between plasma and serum levels are congruent with their representing separate pools of BDNF. The observation of higher basal serum BDNF in the AD group without a concomitant elevation in plasma BDNF levels indicates that the elevated serum BDNF in AD patients is not due to greater BDNF exposure. Further research is warranted to fully elucidate mechanisms underlying this alteration and determine the utility of serum BDNF as a predictor or surrogate marker of chronic alcohol abuse. PMID:22364688

Intra-individual variability in information processing speed reflects white matter microstructure in multiple sclerosis.

PubMed

Mazerolle, Erin L; Wojtowicz, Magdalena A; Omisade, Antonina; Fisk, John D

2013-01-01

Slowed information processing speed is commonly reported in persons with multiple sclerosis (MS), and is typically investigated using clinical neuropsychological tests, which provide sensitive indices of mean-level information processing speed. However, recent studies have demonstrated that within-person variability or intra-individual variability (IIV) in information processing speed may be a more sensitive indicator of neurologic status than mean-level performance on clinical tests. We evaluated the neural basis of increased IIV in mildly affected relapsing-remitting MS patients by characterizing the relation between IIV (controlling for mean-level performance) and white matter integrity using diffusion tensor imaging (DTI). Twenty women with relapsing-remitting MS and 20 matched control participants completed the Computerized Test of Information Processing (CTIP), from which both mean response time and IIV were calculated. Other clinical measures of information processing speed were also collected. Relations between IIV on the CTIP and DTI metrics of white matter microstructure were evaluated using tract-based spatial statistics. We observed slower and more variable responses on the CTIP in MS patients relative to controls. Significant relations between white matter microstructure and IIV were observed for MS patients. Increased IIV was associated with reduced integrity in more white matter tracts than was slowed information processing speed as measured by either mean CTIP response time or other neuropsychological test scores. Thus, despite the common use of mean-level performance as an index of cognitive dysfunction in MS, IIV may be more sensitive to the overall burden of white matter disease at the microstructural level. Furthermore, our study highlights the potential value of considering within-person fluctuations, in addition to mean-level performance, for uncovering brain-behavior relationships in neurologic disorders with widespread white matter pathology.

Predictors of HIV/AIDS Programming in African American Churches: Implications for Prevention, Testing and Care

PubMed Central

Stewart, Jennifer M.; Hanlon, Alexandra; Brawner, Bridgette M.

2017-01-01

Using data from the National Congregational Study, we examined predictors of having a HIV/AIDS program in predominately African American churches across the United States. We conducted regression analyses of Wave II data (N = 1,506) isolating the sample to churches with a predominately African American membership. The dependent variable asked whether or not the congregation currently had any program focused on HIV or AIDS. Independent variables included several variables from the individual, organizational, and social levels. Our study revealed that region, clergy age, congregant disclosure of HIV-positive status, permitting cohabiting couples to be members, sponsorship or participation in programs targeted to physical health issues and having a designated person or committee to address health-focused programs significantly increased the likelihood of African American churches having a HIV/AIDS program. A paucity of nationally representative research focuses on the social, organizational and individual level predictors of having HIV/AIDS programs in African American churches. Determining the characteristics of churches with HIV/AIDS programming at multiple levels is a critical and necessary approach with significant implications for partnering with African American churches in HIV initiatives. PMID:27540035

Individual and Work-Related Factors Influencing Burnout of Mental Health Professionals: A Meta-Analysis

ERIC Educational Resources Information Center

Lim, Nayoung; Kim, Eun Kyoung; Kim, Hyunjung; Yang, Eunjoo; Lee, Sang Min

2010-01-01

The current study identifies and assesses individual and work-related factors as correlates of burnout among mental health professionals. Results of a meta-analysis indicate that age and work setting variables are the most significant indicators of emotional exhaustion and depersonalization. In terms of level of personal accomplishment, the age…

The Effects of Selected Variables on Problems Facing Handicapped in the United Arab Emirates.

ERIC Educational Resources Information Center

Sartawi, A. A. M.

1996-01-01

Individuals (n=125, ages 15 to 25) with disabilities in the United Arab Emirates were surveyed concerning gender, disability type and cause, parental status, and level of family income. Results indicated that: (1) individuals with acquired disabilities had more problems than those with congenital disabilities, and (2) people with physical…

The Production and Destruction of Individual Competence: The Role of Vocational Experience

ERIC Educational Resources Information Center

Suleman, Fatima; Paul, Jean-Jacques

2007-01-01

This article presents the results of research into the impact on individual skill levels of the variables traditionally represented by human capital. The discussion is centred around the way in which education and vocational experience contribute to the process of producing useful skills in the job market or, conversely, of making them obsolete.…

Racial Bullying and Victimization in Canadian School-Aged Children: Individual and School Level Effects

ERIC Educational Resources Information Center

Larochette, Anne-Claire; Murphy, Ashley Nicole; Craig, Wendy M.

2010-01-01

Numerous individual factors, including race, have been identified to date that may place children at risk for bullying involvement. The importance of the school's environment on bullying behaviours has also been highlighted, as the majority of bullying occurs at school. The variables associated with racial bullying and victimization, however, have…

Using Social Disorganization Theory to Guide Substance Abuse Prevention among Adolescents: Implications for Educators

ERIC Educational Resources Information Center

Jaynes, Shane

2014-01-01

Substance use and abuse are problematic in the lives of adolescents, including interpersonal problems and scholastic problems. Risk for substance use has commonly been assessed at the individual level. This paper examines risk of adolescent substance abuse as a variable impacted by environmental or contextual factors surrounding the individual.…

Family functionality: a study of Brazilian institutionalized elderly individuals.

PubMed

de Oliveira, Simone Camargo; Pavarini, Sofia Cristina Iost; Orlandi, Fabiana de Souza; de Mendiondo, Marisa Silvana Zazzeta

2014-01-01

This study presents an analysis of a potential association between family functionality and the variables of gender, length of institutionalization, family composition, depressive symptoms, and cognitive disorders in elderly individuals living in Long-Term Care Facilities (LTCF) in a city in the interior of São Paulo, Brazil. This is a quantitative, cross-sectional study with a descriptive-correlational design. A total of 107 institutionalized elderly individuals were interviewed. Data were analyzed through raw and adjusted Logistic Regression. The results indicate that most elderly individuals experience family dysfunction, 57% present a high level of family dysfunction, 21% present moderate family dysfunction and 22% present good family functionality. There was a statistical association between the Family APGAR and the variables of length of institutionalization, depressive symptoms, family composition and cognitive disorders. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Using stable isotopes to investigate individual diet specialization in California sea otters (Enhydra lutris nereis)

USGS Publications Warehouse

Newsome, S.D.; Tinker, M.T.; Monson, Daniel H.; Oftedal, O.T.; Ralls, K.; Staedler, M.M.; Fogel, M.L.; Estes, J.A.

2009-01-01

Differences in diet composition among conspecifics (dietary specialization) have been documented across a broad range of taxonomic groups and habitats, and such variation at the individual level is increasingly recognized as an important component of diversity in trophic interactions. Accurate identification of individual dietary specialization, however, requires longitudinal dietary records that are labor-intensive and cost-prohibitive to obtain for many species. Here we explore the use of stable isotopes (δ13C and δ15N) as a promising technique for detecting and quantifying patterns of individual dietary specialization. Southern sea otters (Enhydra lutris nereis) offer a unique opportunity for testing this approach because (1) they consume a wide variety of prey that span multiple trophic levels, habitats, and ecologically defined functional groups; and (2) individual diet specialization can be validated with existing observational data. We analyzed the isotopic composition of sea otter vibrissae (n = 31) in order to characterize inter- and intra-individual variation in sea otter diets at Monterey Bay, California, USA. At the population level, sea otters showed substantial variation in both δ13C and δ15N values, occupying nearly all of the “isotopic space” created by the diversity of isotopic signatures of potential prey taxa. Most of the variation in sea otter vibrissae was accounted for by differences between individuals, with much less contributed by within-individual variation. A majority of sea otters (∼80%) showed relatively little temporal variability in isotopic composition, suggesting that the proportional composition of most individuals' diets is relatively constant over time; a few individuals (∼20%) exhibited a high degree of intra-vibrissa isotopic variability, suggesting seasonal shifts in diet composition. These results and our interpretation of them were supported by long-term observational data on the diets of radio-tagged sea otters from the same population (n = 23). Our results demonstrate that stable isotopes can provide an efficient tool for measuring individual- and population-level dietary breadth and may be useful for studying populations where longitudinal data on individuals would otherwise be impossible to acquire. This will be critical for examining the causes and consequences of dietary variation within and among consumer populations, thereby improving our understanding of these important ecological and evolutionary processes at the community level.

Cerebrospinal Fluid Biomarkers and Reserve Variables as Predictors of Future "Non-Cognitive" Outcomes of Alzheimer's Disease.

PubMed

Ingber, Adam P; Hassenstab, Jason; Fagan, Anne M; Benzinger, Tammie L S; Grant, Elizabeth A; Holtzman, David M; Morris, John C; Roe, Catherine M

2016-01-01

The influence of reserve variables and Alzheimer's disease (AD) biomarkers on cognitive test performance has been fairly well-characterized. However, less is known about the influence of these factors on "non-cognitive" outcomes, including functional abilities and mood. We examined whether cognitive and brain reserve variables mediate how AD biomarker levels in cognitively normal persons predict future changes in function, mood, and neuropsychiatric behavior. Non-cognitive outcomes were examined in 328 individuals 50 years and older enrolled in ongoing studies of aging and dementia at the Knight Alzheimer Disease Research Center (ADRC). All participants were cognitively normal at baseline (Clinical Dementia Rating [CDR] 0), completed cerebrospinal fluid (CSF) and structural neuroimaging studies within one year of baseline, and were followed for an average of 4.6 annual visits. Linear mixed effects models explored how cognitive reserve and brain reserve variables mediate the relationships between AD biomarker levels and changes in function, mood, and neuropsychiatric behavior in cognitively normal participants. Education levels did not have a significant effect on predicting non-cognitive decline. However, participants with smaller brain volumes exhibited the worst outcomes on measures of mood, functional abilities, and behavioral disturbance. This effect was most pronounced in individuals who also had abnormal CSF biomarkers. The findings suggest that brain reserve plays a stronger, or earlier, role than cognitive reserve in protecting against non-cognitive impairment in AD.

Inter-individual variability in copepod microbiomes reveals bacterial networks linked to host physiology.

PubMed

Datta, Manoshi S; Almada, Amalia A; Baumgartner, Mark F; Mincer, Tracy J; Tarrant, Ann M; Polz, Martin F

2018-06-06

Copepods harbor diverse bacterial communities, which collectively carry out key biogeochemical transformations in the ocean. However, bulk copepod sampling averages over the variability in their associated bacterial communities, thereby limiting our understanding of the nature and specificity of copepod-bacteria associations. Here, we characterize the bacterial communities associated with nearly 200 individual Calanus finmarchicus copepods transitioning from active growth to diapause. We find that all individual copepods sampled share a small set of "core" operational taxonomic units (OTUs), a subset of which have also been found associated with other marine copepod species in different geographic locations. However, most OTUs are patchily distributed across individual copepods, thereby driving community differences across individuals. Among patchily distributed OTUs, we identified groups of OTUs correlated with common ecological drivers. For instance, a group of OTUs positively correlated with recent copepod feeding served to differentiate largely active growing copepods from those entering diapause. Together, our results underscore the power of individual-level sampling for understanding host-microbiome relationships.

Effects of neighbourhood-level educational attainment on HIV prevalence among young women in Zambia.

PubMed

Kayeyi, Nkomba; Sandøy, Ingvild F; Fylkesnes, Knut

2009-08-25

Investigations of the association between socio-economic position indicators and HIV in East, Central and Southern Africa have chiefly focused on factors that pertain to individual-level characteristics. This study investigated the effect of neighbourhood educational attainment on HIV prevalence among young women in selected urban and rural areas in Zambia. This study re-analysed data from a cross-sectional population survey conducted in Zambia in 2003. The analyses were restricted to women aged 15-24 years (n = 1295). Stratified random cluster sampling was used to select 10 urban and 10 rural clusters. A measure for neighbourhood-level educational attainment was constructed by aggregating individual-level years-in-school. Multi-level mixed effects regression models were run to examine the neighbourhood-level educational effect on HIV prevalence after adjusting for individual-level underlying variables (education, currently a student, marital status) and selected proximate determinants (ever given birth, sexual activity, lifetime sexual partners). HIV prevalence among young women aged 15-24 years was 12.5% in the urban and 6.8% in the rural clusters. Neighbourhood educational attainment was found to be a strong determinant of HIV infection in both urban and rural population, i.e. HIV prevalence decreased substantially by increasing level of neighbourhood education. The likelihood of infection in low vs. high educational attainment of neighbourhoods was 3.4 times among rural women and 1.8 times higher among the urban women after adjusting for age and other individual-level underlying variables, including education. However, the association was not significant for urban young women after this adjustment. After adjusting for level of education in the neighbourhood, the effect of the individual-level education differed by residence, i.e. a strong protective effect among urban women whereas tending to be a risk factor among rural women. The findings suggested structural effects on HIV prevalence. Future research should include more detailed mapping of neighbourhood factors of relevance to HIV transmission as part of the effort to better understand the causal mechanisms involved.

How does variation in the environment and individual cognition explain the existence of consistent behavioral differences?

PubMed Central

Niemelä, Petri T; Vainikka, Anssi; Forsman, Jukka T; Loukola, Olli J; Kortet, Raine

2013-01-01

According to recent studies on animal personalities, the level of behavioral plasticity, which can be viewed as the slope of the behavioral reaction norm, varies among individuals, populations, and species. Still, it is conceptually unclear how the interaction between environmental variation and variation in animal cognition affect the evolution of behavioral plasticity and expression of animal personalities. Here, we (1) use literature to review how environmental variation and individual variation in cognition explain population and individual level expression of behavioral plasticity and (2) draw together empirically yet nontested, conceptual framework to clarify how these factors affect the evolution and expression of individually consistent behavior in nature. The framework is based on simple principles: first, information acquisition requires cognition that is inherently costly to build and maintain. Second, individual differences in animal cognition affect the differences in behavioral flexibility, i.e. the variance around the mean of the behavioral reaction norm, which defines plasticity. Third, along the lines of the evolution of cognition, we predict that environments with moderate variation favor behavioral flexibility. This occurs since in those environments costs of cognition are covered by being able to recognize and use information effectively. Similarly, nonflexible, stereotypic behaviors may be favored in environments that are either invariable or highly variable, since in those environments cognition does not give any benefits to cover the costs or cognition is not able to keep up with environmental change, respectively. If behavioral plasticity develops in response to increasing environmental variability, plasticity should dominate in environments that are moderately variable, and expression of animal personalities and behavioral syndromes may differ between environments. We give suggestions how to test our hypothesis and propose improvements to current behavioral testing protocols in the field of animal personality. PMID:23467316

A Bayesian random effects discrete-choice model for resource selection: Population-level selection inference

USGS Publications Warehouse

Thomas, D.L.; Johnson, D.; Griffith, B.

2006-01-01

Modeling the probability of use of land units characterized by discrete and continuous measures, we present a Bayesian random-effects model to assess resource selection. This model provides simultaneous estimation of both individual- and population-level selection. Deviance information criterion (DIC), a Bayesian alternative to AIC that is sample-size specific, is used for model selection. Aerial radiolocation data from 76 adult female caribou (Rangifer tarandus) and calf pairs during 1 year on an Arctic coastal plain calving ground were used to illustrate models and assess population-level selection of landscape attributes, as well as individual heterogeneity of selection. Landscape attributes included elevation, NDVI (a measure of forage greenness), and land cover-type classification. Results from the first of a 2-stage model-selection procedure indicated that there is substantial heterogeneity among cow-calf pairs with respect to selection of the landscape attributes. In the second stage, selection of models with heterogeneity included indicated that at the population-level, NDVI and land cover class were significant attributes for selection of different landscapes by pairs on the calving ground. Population-level selection coefficients indicate that the pairs generally select landscapes with higher levels of NDVI, but the relationship is quadratic. The highest rate of selection occurs at values of NDVI less than the maximum observed. Results for land cover-class selections coefficients indicate that wet sedge, moist sedge, herbaceous tussock tundra, and shrub tussock tundra are selected at approximately the same rate, while alpine and sparsely vegetated landscapes are selected at a lower rate. Furthermore, the variability in selection by individual caribou for moist sedge and sparsely vegetated landscapes is large relative to the variability in selection of other land cover types. The example analysis illustrates that, while sometimes computationally intense, a Bayesian hierarchical discrete-choice model for resource selection can provide managers with 2 components of population-level inference: average population selection and variability of selection. Both components are necessary to make sound management decisions based on animal selection.

Psychosocial work dimensions, personality, and body mass index: sex differences.

PubMed

Blanch, Angel; Aluja, Anton

2013-08-01

The association between psychosocial work dimensions (i.e. demand and control) and obesity has been found to be inconclusive, indicating that individual differences factors might also contribute to explain the variability in BMI. The interaction between work dimensions and personality variables in a group of male and female workers (N = 506), and its associations with BMI were analyzed with a cross-sectional study with self-report data. Hierarchical regression analyses were used to predict the BMI levels from work and individual differences variables and their interactions for males and females. The main effects of personality variables were not significant, physical workload interacted with neuroticism for males, whereas control interacted with activity for females. Psychosocial work dimensions and personality traits were related to BMI for men and women. These outcomes reinforce the notion that different models might account for the explanatory mechanisms of BMI in regard to sex.

Intimate partner violence against women in Nepal: an analysis through individual, empowerment, family and societal level factors.

PubMed

Dalal, Koustuv; Wang, Shumei; Svanström, Leif

2014-01-01

The current study estimated the national prevalence rate of intimate partner violence against women (IPVAW) in Nepal. Besides, the individual level, empowerment level, family and societal level factors were assessed to relate with the victims of IPAVW in Nepal. Nationally representative sample of 4210 women of reproductive age (15-49 yr) were included in the study. Household surveys using two stage sampling procedures, face to face interview with pre-tested questionnaires were performed. Emotional, physical and sexual violence were target variables. A violence variable was constructed from these three types of violence. Individual level factors were measured by age, residency, education, religion and husband's education. Empowerment factors included employment status and various decision making elements. Family and societal factors included economic status, neighborhood socioeconomic disadvantage index, history of family violence, husband's controlling behavior and other issues. Cross tabulation with chi-square tests and multivariate logistic regression were employed. Prevalence of emotional IPVAW was 17.5%, physical IPAVW 23.4% and sexual IPAVW 14.7%. Overall the prevalence of IPVAW in Nepal was 32.4%. Joint decision making for contraception, husband's non-controlling behavior to wives and friendly feelings were emerged as less likely to be IPVAW perpetration. The findings have immense policy importance as a nationally representative study and indicating necessity of more gender equality.

How important are determinants of obesity measured at the individual level for explaining geographic variation in body mass index distributions? Observational evidence from Canada using Quantile Regression and Blinder-Oaxaca Decomposition.

PubMed

Dutton, Daniel J; McLaren, Lindsay

2016-04-01

Obesity prevalence varies between geographic regions in Canada. The reasons for this variation are unclear but most likely implicate both individual-level and population-level factors. The objective of this study was to examine whether equalising correlates of body mass index (BMI) across these geographic regions could be reasonably expected to reduce differences in BMI distributions between regions. Using data from three cycles of the Canadian Community Health Survey (CCHS) 2001, 2003 and 2007 for males and females, we modelled between-region BMI cross-sectionally using quantile regression and Blinder-Oaxaca decomposition of the quantile regression results. We show that while individual-level variables (ie, age, income, education, physical activity level, fruit and vegetable consumption, smoking status, drinking status, family doctor status, rural status, employment in the past 12 months and marital status) may be Caucasian important correlates of BMI within geographic regions, those variables are not capable of explaining variation in BMI between regions. Equalisation of common correlates of BMI between regions cannot be reasonably expected to reduce differences in the BMI distributions between regions. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Predictors of Self-Directed Learning for Low-Qualified Employees: A Multi-Level Analysis

ERIC Educational Resources Information Center

Raemdonck, Isabel; van der Leeden, Rien; Valcke, Martin; Segers, Mien; Thijssen, Jo

2012-01-01

Purpose: This study aims to examine which variables at the level of the individual employee and at the company level are predictors of self-directed learning in low-qualified employees. Methodology: Results were obtained from a sample of 408 low-qualified employees from 35 different companies. The companies were selected from the energy sector,…

Generalized SAMPLE SIZE Determination Formulas for Investigating Contextual Effects by a Three-Level Random Intercept Model.

PubMed

Usami, Satoshi

2017-03-01

Behavioral and psychological researchers have shown strong interests in investigating contextual effects (i.e., the influences of combinations of individual- and group-level predictors on individual-level outcomes). The present research provides generalized formulas for determining the sample size needed in investigating contextual effects according to the desired level of statistical power as well as width of confidence interval. These formulas are derived within a three-level random intercept model that includes one predictor/contextual variable at each level to simultaneously cover various kinds of contextual effects that researchers can show interest. The relative influences of indices included in the formulas on the standard errors of contextual effects estimates are investigated with the aim of further simplifying sample size determination procedures. In addition, simulation studies are performed to investigate finite sample behavior of calculated statistical power, showing that estimated sample sizes based on derived formulas can be both positively and negatively biased due to complex effects of unreliability of contextual variables, multicollinearity, and violation of assumption regarding the known variances. Thus, it is advisable to compare estimated sample sizes under various specifications of indices and to evaluate its potential bias, as illustrated in the example.

Truncating Variants in NAA15 Are Associated with Variable Levels of Intellectual Disability, Autism Spectrum Disorder, and Congenital Anomalies.

PubMed

Cheng, Hanyin; Dharmadhikari, Avinash V; Varland, Sylvia; Ma, Ning; Domingo, Deepti; Kleyner, Robert; Rope, Alan F; Yoon, Margaret; Stray-Pedersen, Asbjørg; Posey, Jennifer E; Crews, Sarah R; Eldomery, Mohammad K; Akdemir, Zeynep Coban; Lewis, Andrea M; Sutton, Vernon R; Rosenfeld, Jill A; Conboy, Erin; Agre, Katherine; Xia, Fan; Walkiewicz, Magdalena; Longoni, Mauro; High, Frances A; van Slegtenhorst, Marjon A; Mancini, Grazia M S; Finnila, Candice R; van Haeringen, Arie; den Hollander, Nicolette; Ruivenkamp, Claudia; Naidu, Sakkubai; Mahida, Sonal; Palmer, Elizabeth E; Murray, Lucinda; Lim, Derek; Jayakar, Parul; Parker, Michael J; Giusto, Stefania; Stracuzzi, Emanuela; Romano, Corrado; Beighley, Jennifer S; Bernier, Raphael A; Küry, Sébastien; Nizon, Mathilde; Corbett, Mark A; Shaw, Marie; Gardner, Alison; Barnett, Christopher; Armstrong, Ruth; Kassahn, Karin S; Van Dijck, Anke; Vandeweyer, Geert; Kleefstra, Tjitske; Schieving, Jolanda; Jongmans, Marjolijn J; de Vries, Bert B A; Pfundt, Rolph; Kerr, Bronwyn; Rojas, Samantha K; Boycott, Kym M; Person, Richard; Willaert, Rebecca; Eichler, Evan E; Kooy, R Frank; Yang, Yaping; Wu, Joseph C; Lupski, James R; Arnesen, Thomas; Cooper, Gregory M; Chung, Wendy K; Gecz, Jozef; Stessman, Holly A F; Meng, Linyan; Lyon, Gholson J

2018-05-03

N-alpha-acetylation is a common co-translational protein modification that is essential for normal cell function in humans. We previously identified the genetic basis of an X-linked infantile lethal Mendelian disorder involving a c.109T>C (p.Ser37Pro) missense variant in NAA10, which encodes the catalytic subunit of the N-terminal acetyltransferase A (NatA) complex. The auxiliary subunit of the NatA complex, NAA15, is the dimeric binding partner for NAA10. Through a genotype-first approach with whole-exome or genome sequencing (WES/WGS) and targeted sequencing analysis, we identified and phenotypically characterized 38 individuals from 33 unrelated families with 25 different de novo or inherited, dominantly acting likely gene disrupting (LGD) variants in NAA15. Clinical features of affected individuals with LGD variants in NAA15 include variable levels of intellectual disability, delayed speech and motor milestones, and autism spectrum disorder. Additionally, mild craniofacial dysmorphology, congenital cardiac anomalies, and seizures are present in some subjects. RNA analysis in cell lines from two individuals showed degradation of the transcripts with LGD variants, probably as a result of nonsense-mediated decay. Functional assays in yeast confirmed a deleterious effect for two of the LGD variants in NAA15. Further supporting a mechanism of haploinsufficiency, individuals with copy-number variant (CNV) deletions involving NAA15 and surrounding genes can present with mild intellectual disability, mild dysmorphic features, motor delays, and decreased growth. We propose that defects in NatA-mediated N-terminal acetylation (NTA) lead to variable levels of neurodevelopmental disorders in humans, supporting the importance of the NatA complex in normal human development. Copyright © 2018 American Society of Human Genetics. All rights reserved.

The Association Among Individual and Contextual Factors and Unmet Healthcare Needs in South Korea: A Multilevel Study Using National Data.

PubMed

Lee, Seung Eun; Yeon, Miyeon; Kim, Chul-Woung; Yoon, Tae-Ho

2016-09-01

The objective of this study is to investigate associations between contextual characteristics and unmet healthcare needs in South Korea after accounting for individual factors. The present study used data from the 2012 Korean Community Health Survey (KCHS) of 228 902 adults residing within 253 municipal districts in South Korea. A multilevel analysis was conducted to investigate how contextual characteristics, defined by variables that describe the regional deprivation, degree of urbanity, and healthcare supply, are associated with unmet needs after controlling for individual-level variables. Of the surveyed Korean adults, 12.1% reported experiencing unmet healthcare needs in the past. This figure varied with the 253 districts surveyed, ranging from 2.6% to 26.2%. A multilevel analysis found that the association between contextual characteristics and unmet needs varied according to the factors that caused the unmet needs. The degree of urbanity was associated with unmet need due to "financial burden" (odds ratio [OR], 0.53; 95% confidence interval [CI], 0.42 to 0.66 for rural vs. metropolitan), but not unmet need due to "service not available when needed." There were no significant associations between these unmet need measures and regional deprivation. Among individual-level variables, income level showed the highest association with unmet need due to "financial burden" (OR, 5.63; 95% CI, 4.76 to 6.66), while employment status showed a strong association with unmet need due to "service not available when needed." Our finding suggests that different policy interventions should be considered for each at-risk population group to address the root cause of unmet healthcare needs.

Temporal structure of motor variability is dynamically regulated and predicts motor learning ability.

PubMed

Wu, Howard G; Miyamoto, Yohsuke R; Gonzalez Castro, Luis Nicolas; Ölveczky, Bence P; Smith, Maurice A

2014-02-01

Individual differences in motor learning ability are widely acknowledged, yet little is known about the factors that underlie them. Here we explore whether movement-to-movement variability in motor output, a ubiquitous if often unwanted characteristic of motor performance, predicts motor learning ability. Surprisingly, we found that higher levels of task-relevant motor variability predicted faster learning both across individuals and across tasks in two different paradigms, one relying on reward-based learning to shape specific arm movement trajectories and the other relying on error-based learning to adapt movements in novel physical environments. We proceeded to show that training can reshape the temporal structure of motor variability, aligning it with the trained task to improve learning. These results provide experimental support for the importance of action exploration, a key idea from reinforcement learning theory, showing that motor variability facilitates motor learning in humans and that our nervous systems actively regulate it to improve learning.

Temporal structure of motor variability is dynamically regulated and predicts motor learning ability

PubMed Central

Wu, Howard G; Miyamoto, Yohsuke R; Castro, Luis Nicolas Gonzalez; Ölveczky, Bence P; Smith, Maurice A

2015-01-01

Individual differences in motor learning ability are widely acknowledged, yet little is known about the factors that underlie them. Here we explore whether movement-to-movement variability in motor output, a ubiquitous if often unwanted characteristic of motor performance, predicts motor learning ability. Surprisingly, we found that higher levels of task-relevant motor variability predicted faster learning both across individuals and across tasks in two different paradigms, one relying on reward-based learning to shape specific arm movement trajectories and the other relying on error-based learning to adapt movements in novel physical environments. We proceeded to show that training can reshape the temporal structure of motor variability, aligning it with the trained task to improve learning. These results provide experimental support for the importance of action exploration, a key idea from reinforcement learning theory, showing that motor variability facilitates motor learning in humans and that our nervous systems actively regulate it to improve learning. PMID:24413700

Individual differences in implicit motor learning: task specificity in sensorimotor adaptation and sequence learning.

PubMed

Stark-Inbar, Alit; Raza, Meher; Taylor, Jordan A; Ivry, Richard B

2017-01-01

In standard taxonomies, motor skills are typically treated as representative of implicit or procedural memory. We examined two emblematic tasks of implicit motor learning, sensorimotor adaptation and sequence learning, asking whether individual differences in learning are correlated between these tasks, as well as how individual differences within each task are related to different performance variables. As a prerequisite, it was essential to establish the reliability of learning measures for each task. Participants were tested twice on a visuomotor adaptation task and on a sequence learning task, either the serial reaction time task or the alternating reaction time task. Learning was evident in all tasks at the group level and reliable at the individual level in visuomotor adaptation and the alternating reaction time task but not in the serial reaction time task. Performance variability was predictive of learning in both domains, yet the relationship was in the opposite direction for adaptation and sequence learning. For the former, faster learning was associated with lower variability, consistent with models of sensorimotor adaptation in which learning rates are sensitive to noise. For the latter, greater learning was associated with higher variability and slower reaction times, factors that may facilitate the spread of activation required to form predictive, sequential associations. Interestingly, learning measures of the different tasks were not correlated. Together, these results oppose a shared process for implicit learning in sensorimotor adaptation and sequence learning and provide insight into the factors that account for individual differences in learning within each task domain. We investigated individual differences in the ability to implicitly learn motor skills. As a prerequisite, we assessed whether individual differences were reliable across test sessions. We found that two commonly used tasks of implicit learning, visuomotor adaptation and the alternating serial reaction time task, exhibited good test-retest reliability in measures of learning and performance. However, the learning measures did not correlate between the two tasks, arguing against a shared process for implicit motor learning. Copyright © 2017 the American Physiological Society.

Mapping cortical brain asymmetry in 17,141 healthy individuals worldwide via the ENIGMA Consortium.

PubMed

Kong, Xiang-Zhen; Mathias, Samuel R; Guadalupe, Tulio; Glahn, David C; Franke, Barbara; Crivello, Fabrice; Tzourio-Mazoyer, Nathalie; Fisher, Simon E; Thompson, Paul M; Francks, Clyde

2018-05-29

Hemispheric asymmetry is a cardinal feature of human brain organization. Altered brain asymmetry has also been linked to some cognitive and neuropsychiatric disorders. Here, the ENIGMA (Enhancing NeuroImaging Genetics through Meta-Analysis) Consortium presents the largest-ever analysis of cerebral cortical asymmetry and its variability across individuals. Cortical thickness and surface area were assessed in MRI scans of 17,141 healthy individuals from 99 datasets worldwide. Results revealed widespread asymmetries at both hemispheric and regional levels, with a generally thicker cortex but smaller surface area in the left hemisphere relative to the right. Regionally, asymmetries of cortical thickness and/or surface area were found in the inferior frontal gyrus, transverse temporal gyrus, parahippocampal gyrus, and entorhinal cortex. These regions are involved in lateralized functions, including language and visuospatial processing. In addition to population-level asymmetries, variability in brain asymmetry was related to sex, age, and intracranial volume. Interestingly, we did not find significant associations between asymmetries and handedness. Finally, with two independent pedigree datasets ( n = 1,443 and 1,113, respectively), we found several asymmetries showing significant, replicable heritability. The structural asymmetries identified and their variabilities and heritability provide a reference resource for future studies on the genetic basis of brain asymmetry and altered laterality in cognitive, neurological, and psychiatric disorders.

Death anxiety as a predictor of future time orientation among individuals with spinal cord injuries.

PubMed

Martz, E; Livneh, H

2003-09-16

The purpose of this study was to examine the relationship between death anxiety and future time orientation among individuals who sustained spinal cord injuries (SCI). Participants were 317 individuals with SCI, of whom 57.4% were US veterans. Data were obtained by means of mailed questionnaires and included responses to the Death Anxiety Scale (DAS), the Future Time Orientation (FTOS) measure, as well as information on participants' personal and disability-related characteristics. A hierarchical multiple regression analysis was conducted to examine the influence of a set of demographic variables, followed by a set of disability-related variables, and finally two factorially-derived measures of death anxiety (denial of death and distressed awareness of death) on future time orientation. Two disability-related variables (pain level and existence of pressure ulcers) and one of the two death anxiety measures (distressed awareness of death) significantly predicted future time orientation. A post-hoc analysis, adding depression as a predictor, was also significant, indicating that an increased level of depression uniquely contributed to a truncated future time orientation. Distressed anxiety and depression may be important factors affecting goals and plans of people with SCI. Future research should attempt to clarify the intricate relationships among negative affectivity, future time orientation, and psychosocial adaptation to SCI.

Psychosocial factors and financial literacy.

PubMed

Murphy, John L

2013-01-01

This study uses data from the Health and Retirement Study (HRS) to analyze the psychological and social variables associated with financial literacy. The HRS is a nationally representative longitudinal survey of individuals older than age 50 and their spouses. An ordinary least squares linear regression analysis explores the relationship between financial literacy and several economic and psychosocial variables. After controlling for earnings, level of education, and other socioeconomic variables in this exploratory study, I find that financial satisfaction and religiosity are correlated with financial literacy.

Do state laws concerning homosexuals reflect the preeminence of conservative-liberal individual differences?

PubMed

McCann, Stewart J H

2011-01-01

The present study was conducted to determine whether individual-level correlates of sexual prejudice (i.e., conservatism-liberalism, religious fundamentalism, educational levels, urbanism, income, and living in the South) are predictive at the state level of laws restricting homosexual behaviors and desires. Criterion 1 was a multifaceted index of state laws concerning gay men and lesbians; Criterion 2 was an index of state laws regarding same-sex partnerships. Multiple regression strategies showed that state conservatism-liberalism, as determined from the responses of 141,798 individuals aggregated at the state level (Erikson, Wright, & McIver, 1993), was the prime state-level predictor of both criteria. For Criterion 1, only Southern state status accounted for additional variance (4.2%) above the 54.8% already accounted for by conservatism-liberalism. For Criterion 2, no other variables accounted for variance beyond the 44.6% accounted for by state conservatism-liberalism.

Neurobiological degeneracy and affordance perception support functional intra-individual variability of inter-limb coordination during ice climbing.

PubMed

Seifert, Ludovic; Wattebled, Léo; Herault, Romain; Poizat, Germain; Adé, David; Gal-Petitfaux, Nathalie; Davids, Keith

2014-01-01

This study investigated the functional intra-individual movement variability of ice climbers differing in skill level to understand how icefall properties were used by participants as affordances to adapt inter-limb coordination patterns during performance. Seven expert climbers and seven beginners were observed as they climbed a 30 m icefall. Movement and positioning of the left and right hand ice tools, crampons and the climber's pelvis over the first 20 m of the climb were recorded and digitized using video footage from a camera (25 Hz) located perpendicular to the plane of the icefall. Inter-limb coordination, frequency and types of action and vertical axis pelvis displacement exhibited by each climber were analysed for the first five minutes of ascent. Participant perception of climbing affordances was assessed through: (i) calculating the ratio between exploratory movements and performed actions, and (ii), identifying, by self-confrontation interviews, the perceptual variables of environmental properties, which were significant to climbers for their actions. Data revealed that experts used a wider range of upper and lower limb coordination patterns, resulting in the emergence of different types of action and fewer exploratory movements, suggesting that effective holes in the icefall provided affordances to regulate performance. In contrast, beginners displayed lower levels of functional intra-individual variability of motor organization, due to repetitive swinging of ice tools and kicking of crampons to achieve and maintain a deep anchorage, suggesting lack of perceptual attunement and calibration to environmental properties to support climbing performance.

Income diversification and risk for fishermen.

PubMed

Kasperski, Stephen; Holland, Daniel S

2013-02-05

Catches and prices from many fisheries exhibit high interannual variability, leading to variability in the income derived by fishery participants. The economic risk posed by this may be mitigated in some cases if individuals participate in several different fisheries, particularly if revenues from those fisheries are uncorrelated or vary asynchronously. We construct indices of gross income diversification from fisheries at the level of individual vessels and find that the income of the current fleet of vessels on the US West Coast and in Alaska is less diverse than at any point in the past 30 y. We also find a dome-shaped relationship between the variability of individuals' income and income diversification, which implies that a small amount of diversification does not reduce income risk but that higher levels of diversification can substantially reduce the variability of income from fishing. Moving from a single fishery strategy to a 50-25-25 split in revenues reduces the expected coefficient of variation of gross revenues between 24% and 65% for the vessels included in this study. The increasing access restrictions in many marine fisheries through license reductions and moratoriums have the potential to limit fishermen's ability to diversify their income risk across multiple fisheries. Catch share programs often result in consolidation initially and may reduce diversification. However, catch share programs also make it feasible for fishermen to build a portfolio of harvest privileges and potentially reduce their income risk. Therefore, catch share programs create both threats and opportunities for fishermen wishing to maintain diversified fishing strategies.

Income diversification and risk for fishermen

PubMed Central

Kasperski, Stephen; Holland, Daniel S.

2013-01-01

Catches and prices from many fisheries exhibit high interannual variability, leading to variability in the income derived by fishery participants. The economic risk posed by this may be mitigated in some cases if individuals participate in several different fisheries, particularly if revenues from those fisheries are uncorrelated or vary asynchronously. We construct indices of gross income diversification from fisheries at the level of individual vessels and find that the income of the current fleet of vessels on the US West Coast and in Alaska is less diverse than at any point in the past 30 y. We also find a dome-shaped relationship between the variability of individuals' income and income diversification, which implies that a small amount of diversification does not reduce income risk but that higher levels of diversification can substantially reduce the variability of income from fishing. Moving from a single fishery strategy to a 50-25-25 split in revenues reduces the expected coefficient of variation of gross revenues between 24% and 65% for the vessels included in this study. The increasing access restrictions in many marine fisheries through license reductions and moratoriums have the potential to limit fishermen's ability to diversify their income risk across multiple fisheries. Catch share programs often result in consolidation initially and may reduce diversification. However, catch share programs also make it feasible for fishermen to build a portfolio of harvest privileges and potentially reduce their income risk. Therefore, catch share programs create both threats and opportunities for fishermen wishing to maintain diversified fishing strategies. PMID:23341621

Serum potassium decline during hospitalization for acute decompensated heart failure is a predictor of 6-month mortality, independent of N-terminal pro-B-type natriuretic peptide levels: An individual patient data analysis.

PubMed

Salah, Khibar; Pinto, Yigal M; Eurlings, Luc W; Metra, Marco; Stienen, Susan; Lombardi, Carlo; Tijssen, Jan G; Kok, Wouter E

2015-09-01

Limited data exist for the role of serum potassium changes during hospitalization for acute decompensated heart failure (ADHF). The present study investigated the long-term prognostic value of potassium changes during hospitalization in patients admitted for ADHF. Our study is a pooled individual patient data analysis assembled from 3 prospective cohorts comprising 754 patients hospitalized for ADHF. The endpoint was all-cause mortality within 180 days after discharge. Serum potassium levels and N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels were measured at admission and at discharge. A percentage decrease >15% in serum potassium levels occurred in 96 (13%) patients, and an absolute decrease of >0.7 mmol/L in serum potassium levels occurred in 85 (12%) patients; and both were predictors of poor outcome independent of admission or discharge serum potassium. After the addition of other strong predictors of mortality-a 30% change in NT-proBNP during hospitalization, discharge levels of NT-proBNP, renal markers, and other relevant clinical variables-the multivariate hazard ratio of serum potassium percentage reduction of >15% remained an independent predictor of 180-day mortality (hazard ratio 2.06, 95% CI 1.14-3.73). A percentage serum potassium decline of >15% is an independent predictor of 180-day all-cause mortality on top of baseline potassium levels, NT-proBNP levels, renal variables, and other relevant clinical variables. This suggest that patients hospitalized for ADHF with a decline of >15% in serum potassium levels are at risk and thus monitoring and regulating of serum potassium level during hospitalization are needed in these patients. Copyright © 2015 Elsevier Inc. All rights reserved.

Ability to perform daily physical activities in individuals with type 2 diabetes and moderate obesity: a preliminary validation of the Impact of Weight on Activities of Daily Living Questionnaire.

PubMed

Hayes, Risa P; Nelson, David R; Meldahl, Michael L; Curtis, Bradley H

2011-07-01

The aims of this study were (1) to demonstrate the reliability and validity of the Impact of Weight on Activities of Daily Living Questionnaire (IWADL), a measure of ability to perform daily physical activities, in individuals with type 2 diabetes who are moderately obese and (2) to characterize those individuals with low self-reported ability. Data from a web-based survey of individuals with type 2 diabetes and body mass index (BMI) of 30-40 k/mg(2) were used to calculate Cronbach's α and demonstrate both IWADL factorial and construct validity. These data were entered into a multivariable multinomial logistic regression model with survey variables (demographics, health status, weight- and diabetes-related) as the independent variables and three IWADL scoring groups (Low, Medium, and High) as the dependent variables. Study participants were 349 individuals with type 2 diabetes (mean age = 59 years, 44% male, 91% white, mean BMI = 35 k/mg(2)). Factor analysis indicated a one-factor solution for a seven-item IWADL with Cronbach's α = 0.94. Significant (P < 0.05) relationships were identified between IWADL and variables previously shown to be related to level of physical activity. Ten variables remained independently (P < 0.05) related to IWADL scores, including age, gender, health status, current exercise, using exercise programs or hypnosis as a step to lose weight, and self-reported weight history. The IWADL is a reliable and valid measure of the ability of individuals with type 2 diabetes and moderate obesity to perform daily physical activities. This ability may be an important patient-reported end point to include in clinical trials of antihyperglycemic medications that produce weight loss.

Response variability of different anodal transcranial direct current stimulation intensities across multiple sessions.

PubMed

Ammann, Claudia; Lindquist, Martin A; Celnik, Pablo A

It is well known that transcranial direct current stimulation (tDCS) is capable of modulating corticomotor excitability. However, a source of growing concern has been the observed inter- and intra-individual variability of tDCS-responses. Recent studies have assessed whether individuals respond in a predictable manner across repeated sessions of anodal tDCS (atDCS). The findings of these investigations have been inconsistent, and their methods have some limitations (i.e. lack of sham condition or testing only one tDCS intensity). To study inter- and intra-individual variability of atDCS effects at two different intensities on primary motor cortex (M1) excitability. Twelve subjects participated in a crossover study testing 7-min atDCS over M1 in three separate conditions (2 mA, 1 mA, sham) each repeated three times separated by 48 h. Motor evoked potentials were recorded before and after stimulation (up to 30min). Time of testing was maintained consistent within participants. To estimate the reliability of tDCS effects across sessions, we calculated the Intra-class Correlation Coefficient (ICC). AtDCS at 2 mA, but not 1 mA, significantly increased cortical excitability at the group level in all sessions. The overall ICC revealed fair to high reliability of tDCS effects for multiple sessions. Given that the distribution of responses showed important variability in the sham condition, we established a Sham Variability-Based Threshold to classify responses and to track individual changes across sessions. Using this threshold an intra-individual consistent response pattern was then observed only for the 2 mA condition. 2 mA anodal tDCS results in consistent intra- and inter-individual increases of M1 excitability. Copyright © 2017 Elsevier Inc. All rights reserved.

A Nonlinear Mixed Effects Approach for Modeling the Cell-To-Cell Variability of Mig1 Dynamics in Yeast

PubMed Central

Almquist, Joachim; Bendrioua, Loubna; Adiels, Caroline Beck; Goksör, Mattias; Hohmann, Stefan; Jirstrand, Mats

2015-01-01

The last decade has seen a rapid development of experimental techniques that allow data collection from individual cells. These techniques have enabled the discovery and characterization of variability within a population of genetically identical cells. Nonlinear mixed effects (NLME) modeling is an established framework for studying variability between individuals in a population, frequently used in pharmacokinetics and pharmacodynamics, but its potential for studies of cell-to-cell variability in molecular cell biology is yet to be exploited. Here we take advantage of this novel application of NLME modeling to study cell-to-cell variability in the dynamic behavior of the yeast transcription repressor Mig1. In particular, we investigate a recently discovered phenomenon where Mig1 during a short and transient period exits the nucleus when cells experience a shift from high to intermediate levels of extracellular glucose. A phenomenological model based on ordinary differential equations describing the transient dynamics of nuclear Mig1 is introduced, and according to the NLME methodology the parameters of this model are in turn modeled by a multivariate probability distribution. Using time-lapse microscopy data from nearly 200 cells, we estimate this parameter distribution according to the approach of maximizing the population likelihood. Based on the estimated distribution, parameter values for individual cells are furthermore characterized and the resulting Mig1 dynamics are compared to the single cell times-series data. The proposed NLME framework is also compared to the intuitive but limited standard two-stage (STS) approach. We demonstrate that the latter may overestimate variabilities by up to almost five fold. Finally, Monte Carlo simulations of the inferred population model are used to predict the distribution of key characteristics of the Mig1 transient response. We find that with decreasing levels of post-shift glucose, the transient response of Mig1 tend to be faster, more extended, and displays an increased cell-to-cell variability. PMID:25893847

A comprehensive sensitivity analysis of microarray breast cancer classification under feature variability

PubMed Central

2009-01-01

Background Large discrepancies in signature composition and outcome concordance have been observed between different microarray breast cancer expression profiling studies. This is often ascribed to differences in array platform as well as biological variability. We conjecture that other reasons for the observed discrepancies are the measurement error associated with each feature and the choice of preprocessing method. Microarray data are known to be subject to technical variation and the confidence intervals around individual point estimates of expression levels can be wide. Furthermore, the estimated expression values also vary depending on the selected preprocessing scheme. In microarray breast cancer classification studies, however, these two forms of feature variability are almost always ignored and hence their exact role is unclear. Results We have performed a comprehensive sensitivity analysis of microarray breast cancer classification under the two types of feature variability mentioned above. We used data from six state of the art preprocessing methods, using a compendium consisting of eight diferent datasets, involving 1131 hybridizations, containing data from both one and two-color array technology. For a wide range of classifiers, we performed a joint study on performance, concordance and stability. In the stability analysis we explicitly tested classifiers for their noise tolerance by using perturbed expression profiles that are based on uncertainty information directly related to the preprocessing methods. Our results indicate that signature composition is strongly influenced by feature variability, even if the array platform and the stratification of patient samples are identical. In addition, we show that there is often a high level of discordance between individual class assignments for signatures constructed on data coming from different preprocessing schemes, even if the actual signature composition is identical. Conclusion Feature variability can have a strong impact on breast cancer signature composition, as well as the classification of individual patient samples. We therefore strongly recommend that feature variability is considered in analyzing data from microarray breast cancer expression profiling experiments. PMID:19941644

Individual and contextual determinants of self-reported poor psychological health: a population-based multilevel analysis in southern Sweden.

PubMed

Lindström, Martin; Moghaddassi, Mahnaz; Merlo, Juan

2006-01-01

To investigate the influence of contextual and individual factors on self-reported psychological health. The 2000 public health survey in Scania is a cross-sectional postal questionnaire study with a 59% participation rate. A total of 13,715 persons aged 18-80 answered the questionnaire. A multilevel logistic regression model, with individuals at the first level and municipalities/city quarters at the second, was performed. The effect (intra-class correlation, cross-level modification, and odds ratios) of individual and municipality/city quarter factors on self-reported psychological health was analysed. The crude variance between municipalities/city quarters was small but significant. It was particularly affected and lowered by individual civil status, country of origin, economic stress, and social participation. The inclusion of all individual factors age, sex, civil status, country of origin, education, economic stress, and social participation lowered the between municipality variance to not-significant levels, which is the reason why no contextual variables were included in the calculations. The results of this study suggest that poor self-reported psychological health is affected mainly by individual characteristics of the population and not by contextual factors at the municipality/city quarter level.

Predicting Health Resilience in Pediatric Type 1 Diabetes: A Test of the Resilience Model Framework

PubMed Central

Huang, Bin; Pendley, Jennifer Shroff; Delamater, Alan; Dolan, Lawrence; Reeves, Grafton; Drotar, Dennis

2015-01-01

Objectives This research examined whether individual and family-level factors during the transition from late childhood to early adolescence protected individuals from an increased risk of poor glycemic control across time, which is a predictor of future diabetes-related complications (i.e., health resilience). Methods This longitudinal, multisite study included 239 patients with type 1 diabetes and their caregivers. Glycemic control was based on hemoglobin A1c. Individual and family-level factors included: demographic variables, youth behavioral regulation, adherence (frequency of blood glucose monitoring), diabetes self-management, level of parental support for diabetes autonomy, level of youth mastery and responsibility for diabetes management, and diabetes-related family conflict. Results Longitudinal mixed-effects logistic regression indicated that testing blood glucose more frequently, better self-management, and less diabetes-related family conflict were indicators of health resilience. Conclusions Multiple individual and family-level factors predicted risk for future health complications. Future research should develop interventions targeting specific individual and family-level factors to sustain glycemic control within recommended targets, which reduces the risk of developing future health complications during the transition to adolescence and adulthood. PMID:26152400

Inter- and intra-individual variation in urinary biomarker concentrations over a 6-day sampling period. Part 1: metals.

PubMed

Smolders, Roel; Koch, Holger M; Moos, Rebecca K; Cocker, John; Jones, Kate; Warren, Nick; Levy, Len; Bevan, Ruth; Hays, Sean M; Aylward, Lesa L

2014-12-01

The aim of the current HBM-study is to further the understanding of the impact of inter- and intra-individual variability in HBM surveys as it may have implications for the design and interpretation of the study outcomes. As spot samples only provide a snapshot in time of the concentrations of chemicals in an individual, it remains unclear to what extent intra-individual variability plays a role in the overall variability of population-wide HBM surveys. The current paper describes the results of an intensive biomonitoring study, in which all individual urine samples of 8 individuals were collected over a 6-day sampling period (a total of 352 unique samples). By analyzing different metals (As, Cd, Mn, Ni) in each individual sample, inter- and intra-individual variability for these four metals could be determined, and the relationships between exposure, internal dose, and sampling protocol assessed. Although the range of biomarker values for different metals was well within the normal range reported in large-scale population surveys, large intra-individual differences over a 6-day period could also be observed. Typically, measured biomarker values span at least an order of magnitude within an individual, and more if specific exposure episodes could be identified. Fish consumption for example caused a twenty- to thirty-fold increase in urinary As-levels over a period of 2-6h. Intra-class correlation coefficients (ICC) were typically low for uncorrected biomarker values (between 0.104 and 0.460 for the 4 metals), but improved when corrected for creatinine or specific gravity (SG). The results show that even though urine is a preferred matrix for HBM studies, there are certain methodological issues that need to be taken into account in the interpretation of urinary biomarker data, related to the intrinsic variability of the urination process itself, the relationship between exposure events and biomarker quantification, and the timing of sampling. When setting up HBM-projects, this expected relationship between individual exposure episode and urinary biomarker concentration needs to be taken into account. Copyright © 2014. Published by Elsevier Ireland Ltd.

A prospective analysis of the effect of neighbourhood and individual social capital on changes in self-rated health of people with chronic illness.

PubMed

Waverijn, Geeke; Wolfe, Mary K; Mohnen, Sigrid; Rijken, Mieke; Spreeuwenberg, Peter; Groenewegen, Peter

2014-07-03

Social capital in the living environment, both on the individual and neighbourhood level, is positively associated with people's self-rated health; however, prospective and longitudinal studies are rare, making causal conclusions difficult. To shed more light on the direction of the relationship between social capital and self-rated health, we investigated main and interaction effects of individual and neighbourhood social capital at baseline on changes in self-rated health of people with a somatic chronic disease. Individual social capital, self-rated health and other individual level variables were assessed among a nationwide sample of 1048 non-institutionalized people with a somatic chronic disease residing in 259 neighbourhoods in the Netherlands. The assessment of neighbourhood social capital was based on data from a nationwide survey among the general Dutch population. The association of social capital with changes in self-rated health was assessed by multilevel regression analysis. Both individual social capital and neighbourhood social capital at baseline were significantly associated with changes in self-rated health over the time period of 2005 to 2008 while controlling for several disease characteristics, other individual level and neighbourhood level characteristics. No significant interactions were found between social capital on the individual and on the neighbourhood level. Higher levels of individual and neighbourhood social capital independently and positively affect changes in self-rated health of people with chronic illness. Although most of the variation in health is explained at the individual level, one's social environment should be considered as a possible relevant influence on the health of the chronically ill.

Effects of food availability on growth and reproduction of the deep-sea pedunculate barnacle Heteralepas canci

NASA Astrophysics Data System (ADS)

Yasuda, Natsumi; Miyamoto, Norio; Fujiwara, Yoshihiro; Yamamoto, Tomoko; Yusa, Yoichi

2016-02-01

Sessile animals living on continental shelves or slopes may adjust their growth and reproduction according to temporally and spatially variable food availability, but little information is available on these animals to date. We collected the pedunculate barnacle Heteralepas canci on a continental slope at a depth of 229 m off Cape Nomamisaki in southern Japan. We developed a rearing method for the barnacles and studied their growth and reproduction at different food levels in the laboratory. A total of 136 individual H. canci were fed with Artemia salina larvae and brewer's yeast at three different food levels for 100 days. Both the growth and the ovary development were delayed when food availability was low, whereas the survival rate was lower at the high food level. In addition, an individual survived under complete starvation for 167 days. We concluded that H. canci has plastic life history traits that are adaptive for variable food availability.

The Association Between Long Working Hours and High-Sensitivity C-Reactive Protein in Older Aged Individuals: The Korea National Health and Nutrition Examination Survey (KNHANES) 2015.

PubMed

Lee, Jongin; Kim, Hyoung-Ryoul

2018-05-22

To show the association of hs-CRP level with working hours in different age groups. We used data from Korean National Health and Nutrition Survey. The odds ratios (ORs) and 95% confidence intervals (CIs) of variables for elevated hs-CRP (> 3.0 mg/L) were generated with logistic regression models. Significant variables were verified with an adjusted multivariate logistic model after stratification of age groups. Working for more than 55 hours per week was associated with elevated hs-CRP level in the old-ages group (≥ 60 years old: OR 2.18, 95% CI 1.07-4.45). Working for 40-55 hours per week was associated with decreased hs-CRP in the young-ages group (OR 0.58, 95% CI 0.37-0.93). Working hours appear to influence the levels of hs-CRP in individuals aged older than 60 years.

Individual and contextual determinants of malocclusion in 12-year-old schoolchildren in a Brazilian city.

PubMed

Jordão, Lidia Moraes Ribeiro; Vasconcelos, Daniela Nobre; Moreira, Rafael da Silveira; Freire, Maria do Carmo Matias

2015-01-01

The aim of this study was to describe malocclusion prevalence and its association with individual and contextual factors among Brazilian 12-year-old schoolchildren. This cross-sectional study included data from an oral health survey carried out in Goiânia, Brazil (n = 2,075), and data from the files of the local health authority. The data were collected through oral clinical examinations. The Dental Aesthetic Index (DAI) was used to assess occlusion. The presence of malocclusion (DAI > 25) was used as the dependent variable. The individual independent variables consisted of adolescents' sex and race and their mothers' level of schooling. The clinical variables were caries experience and presence of adverse periodontal condition (calculus and/or gingival bleeding). The contextual variables included type of school and the location of schools in the city's health districts. The Rao-Scott test and multilevel logistic regression were performed. The prevalence of malocclusion was 40.1%. In the final model, significantly higher rates of malocclusion were found among those who attended schools located in less affluent health districts and whose mothers had fewer years of education. Rates were also higher among those presenting calculus and/or gingival bleeding. Malocclusion demonstrated a high prevalence rate and the inequalities in its distribution were determined by individual and contextual factors.

Independent and combined influence of homeownership, occupation, education, income, and community poverty on physical health in persons with arthritis.

PubMed

Callahan, Leigh F; Martin, Kathryn Remmes; Shreffler, Jack; Kumar, Deepak; Schoster, Britta; Kaufman, Jay S; Schwartz, Todd A

2011-05-01

To examine the independent and combined influence of individual- and community-level socioeconomic status (SES) measures on physical health status outcomes in people with self-reported arthritis. From 2004-2005, 968 participants completed a telephone survey assessing health status, chronic conditions, community characteristics, and sociodemographic variables. Individual-level SES measures used included homeownership, occupation (professional or not), educational attainment (less than high school, high school degree, and more than high school), and income (<$15,000, $15,000-$45,000, and >$45,000). Community poverty (2000 US Census block group percentage of individuals living below the poverty line [low, medium, and high]) was used as a community-level SES measure. Outcomes were physical functioning (Medical Outcomes Study Short Form 12 version 2 physical component summary [PCS]), functional disability (Health Assessment Questionnaire [HAQ]), and the Centers for Disease Control and Prevention (CDC) Health-Related Quality of Life (HRQOL) Healthy Days physical and limited activity days, and were analyzed via multivariable regressions. When entered separately, all individual-level SES variables were significantly (P < 0.01) associated with poorer PCS, HAQ, and CDC HRQOL scores. A higher magnitude of effect was seen for household income, specifically <$15,000 per year in final models with all 4 individual SES measures and community poverty. The magnitude of effect for education is reduced and marginally significant for the PCS and number of physically unhealthy days. No effects were seen for occupation, homeownership, and community poverty. Findings confirm that after adjusting for important covariates, lower individual- and community-level SES measures are associated with poorer physical health outcomes, while household income is the strongest predictor (as measured by both significance and effect) of poorer health status in final models. Studies not having participant-reported income available should make use of other SES measures, as they do independently predict physical health. Copyright © 2011 by the American College of Rheumatology.

The different roles of neighbourhood and individual social capital on oral health-related quality of life during pregnancy and postpartum: a multilevel analysis.

PubMed

Lamarca, Gabriela A; Leal, Maria do C; Leao, Anna T T; Sheiham, Aubrey; Vettore, Mario V

2014-04-01

Social capital incorporates neighbourhood and individual levels of interactions and influences health. The objective of this was to assess the association of neighbourhood and individual social capital with oral health-related quality of life (OHRQoL) in pregnant and postpartum women. This was a follow-up prevalence multilevel study on a representative sample of 1248 women grouped into 55 neighbourhoods. OHRQoL was assessed in the postpartum period using the Oral Health Impact Profile questionnaire (OHIP-14). Exploratory variables were gathered during the first trimester of pregnancy and included neighbourhood social capital (neighbourhood-level measure), individual social capital (social support and social networks), demographic and socio-economic variables, oral health measures, and health-related behaviours. The multilevel ordered multinomial logistic regression showed that neighbourhood social capital did not significantly affect women's OHRQoL during pregnancy and postpartum period. Individual social capital measures were independently associated with high OHRQoL. Lack of family social network increased the odds for high OHRQoL (OR = 1.44, 95% CI: 1.08-1.92). Individuals with high levels of positive social interaction were less likely to report high scores of OHRQoL (OR = 0.90, 95% CI: 0.82-0.98). Individual social capital was of greater relevance to women's OHRQoL in and after pregnancy than neighbourhood social capital. These findings suggest that quality of personal and social resources of pregnant women are more important for OHRQoL than the neighbourhoods where the women live. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Alcohol-Related Negative Consequences among Drinkers around the World

PubMed Central

Graham, Kathryn; Bernards, Sharon; Knibbe, Ronald; Kairouz, Sylvia; Kuntche, Sandra; Wilsnack, Sharon C.; Greenfield, Thomas K.; Dietze, Paul; Obot, Isidore; Gmel, Gerhard

2013-01-01

Aims This paper examines (1) gender and country differences in negative consequences related to drinking; (2) relative rates of different consequences; (3) country-level predictors of consequences. Design, setting and participants Multi-level analyses used survey data from the GENACIS collaboration. Measurements Measures included 17 negative consequences grouped into (a) high endorsement acute, (b) personal and (c) social. Country-level measures included average frequency and quantity of drinking, percent current drinkers, Gross Domestic Product (GDP) and Human Development Index (HDI). Findings Overall, the three groupings of consequences were reported by 44%, 12% and 7% of men and by 31%, 6% and 3% of women, respectively. More men than women endorsed all consequences but gender differences were greatest for consequences associated with chronic drinking and social consequences related to male roles. The highest prevalence of consequences was in Uganda, lowest in Uruguay. Personal and social consequences were more likely in countries with higher usual quantity, fewer current drinkers, and lower scores on GDP and HDI. However, significant interactions with individual-level quantity indicated a stronger relationship between consequences and usual quantity among drinkers in countries with lower quantity, more current drinkers and higher scores on GDP and HDI. Conclusions Both gender and country need to be taken into consideration when assessing adverse drinking consequences. Individual measures of alcohol consumption and country-level variables are associated with experiencing such consequences. Additionally, country-level variables affect the strength of the relationship between usual quantity consumed by individuals and adverse consequences. PMID:21395893

Development Of The Social Interest Index

ERIC Educational Resources Information Center

Greever, K. B.; And Others

1973-01-01

A Social Interest Index was developed to measure the level of social interest an individual has attained. Social interest was viewed as the willingness to contribute and cooperate within the areas of four life tasks (works, friendship, love, and self-significance). Findings relate the level of social interest to the variables of sex, socioeconomic…

Towards Energy-Performance Trade-off Analysis of Parallel Applications

ERIC Educational Resources Information Center

Korthikanti, Vijay Anand Reddy

2011-01-01

Energy consumption by computer systems has emerged as an important concern, both at the level of individual devices (limited battery capacity in mobile systems) and at the societal level (the production of Green House Gases). In parallel architectures, applications may be executed on a variable number of cores and these cores may operate at…

Physical activity is related to lower levels of pain, fatigue and depression in individuals with spinal-cord injury: a correlational study.

PubMed

Tawashy, A E; Eng, J J; Lin, K H; Tang, P F; Hung, C

2009-04-01

This was a prospective cross-sectional study for people with chronic spinal cord injury (SCI). To (1) evaluate the intensity level and nature of physical activity in community-dwelling individuals living with SCI, and (2) explore the relation between descriptive individual variables (for example, lesion level), secondary complications and participation in physical activity. Urban community setting. A total of 49 subjects with SCI who used a manual wheelchair for primary mode of mobility (mean years since injury, 11.8; mean age, 43.7 years; 67% paraplegia) completed the physical activity recall assessment for people with SCI (PARA-SCI). Approximately 50% of reported physical activity among individuals with SCI is due to activities of daily living. The amount of physical activity was not related to lesion level, age, body mass index or waistline size. Greater heavy-intensity activity was related to lower levels of pain and fatigue and higher levels of self-efficacy, whereas higher amounts of mild-intensity activity and total activity were related to less depressive symptoms. Activities of daily living are a large component for physical activity among individuals with SCI. It appears that greater physical activity is associated with less secondary complications (pain, fatigue and depression) in individuals with SCI.

Does regional disadvantage affect health-related sport and physical activity level? A multi-level analysis of individual behaviour.

PubMed

Wicker, Pamela; Downward, Paul; Lera-López, Fernando

2017-11-01

This study examines the role of regional government quality in health-related participation in sport and physical activity among adults (18-64 years) in 28 European countries. The importance of the analysis rests in the relative autonomy that regional and local governments have over policy decisions connected with sport and physical activity. While existing studies have focussed on economic and infrastructural investment and expenditure, this research investigates the quality of regional governments across 208 regions within 28 European countries. The individual-level data stem from the 2013 Eurobarometer 80.2 (n = 18,675) and were combined with regional-level data from Eurostat. An individual's level of participation in sport and physical activity was measured by three variables reflecting whether an individual's activity level is below, meets, or exceeds the recommendations of the World Health Organization. The results of multi-level analyses reveal that regional government quality has a significant and positive association with individual participation in sport and physical activity at a level meeting or exceeding the guidelines. The impact is much larger than that of regional gross domestic product per capita, indicating that regional disadvantage in terms of political quality is more relevant than being disadvantaged in terms of economic wealth.

Blood Pressure and Hemodynamic Adaptations after a Training Program in Young Individuals with Down Syndrome

PubMed Central

Seron, Bruna Barboza; Goessler, Karla Fabiana; Modesto, Everaldo Lambert; Almeida, Eloise Werle; Greguol, Márcia

2015-01-01

Background Cardiovascular diseases affect people worldwide. Individuals with Down Syndrome (DS) have an up to sixteen-time greater risk of mortality from cardiovascular diseases. Objective To evaluate the effects of aerobic and resistance exercises on blood pressure and hemodynamic variables of young individuals with DS. Methods A total of 29 young individuals with DS participated in the study. They were divided into two groups: aerobic training (AT) (n = 14), and resistance training (TR) (n = 15). Their mean age was 15.7 ± 2.82 years. The training program lasted 12 weeks, and had a frequency of three times a week for AT and twice a week for RT. AT was performed in treadmill/ bicycle ergometer, at an intensity between 50%-70% of the HR reserve. RT comprised nine exercises with three sets of 12 repetition-maximum. Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean blood pressure (MBP) and hemodynamic variables were assessed beat-to-beat using the Finometer device before/after the training program. Descriptive analysis, the Shapiro-Wilk test to check the normality of data, and the two-way ANOVA for repeated measures were used to compare pre- and post-training variables. The Pearson’s correlation coefficient was calculated to correlate hemodynamic variables. The SPSS version 18.0 was used with the significance level set at p < 0.05. Results After twelve weeks of aerobic and/or resistance training, significant reductions in variables SBP, DBP and MBP were observed. Conclusion This study suggests a chronic hypotensive effect of moderate aerobic and resistance exercises on young individuals with DS. PMID:26131704

Development of a cross-cultural deprivation index in five European countries

PubMed Central

Guillaume, Elodie; Dejardin, Olivier; Launay, Ludivine; Lillini, Roberto; Vercelli, Marina; Marí-Dell'Olmo, Marc; Fernández Fontelo, Amanda; Borrell, Carme; Ribeiro, Ana Isabel; de Pina, Maria Fatima; Mayer, Alexandra; Delpierre, Cyrille; Rachet, Bernard; Launoy, Guy

2016-01-01

Background Despite a concerted policy effort in Europe, social inequalities in health are a persistent problem. Developing a standardised measure of socioeconomic level across Europe will improve the understanding of the underlying mechanisms and causes of inequalities. This will facilitate developing, implementing and assessing new and more effective policies, and will improve the comparability and reproducibility of health inequality studies among countries. This paper presents the extension of the European Deprivation Index (EDI), a standardised measure first developed in France, to four other European countries—Italy, Portugal, Spain and England, using available 2001 and 1999 national census data. Methods and results The method previously tested and validated to construct the French EDI was used: first, an individual indicator for relative deprivation was constructed, defined by the minimal number of unmet fundamental needs associated with both objective (income) poverty and subjective poverty. Second, variables available at both individual (European survey) and aggregate (census) levels were identified. Third, an ecological deprivation index was constructed by selecting the set of weighted variables from the second step that best correlated with the individual deprivation indicator. Conclusions For each country, the EDI is a weighted combination of aggregated variables from the national census that are most highly correlated with a country-specific individual deprivation indicator. This tool will improve both the historical and international comparability of studies, our understanding of the mechanisms underlying social inequalities in health and implementation of intervention to tackle social inequalities in health. PMID:26659762

Aerobic Fitness of Starter and Non-Starter Soccer Players in the Champion’s League

PubMed Central

Paraskevas, Giorgos; Hadjicharalambous, Marios

2018-01-01

Abstract To identify individual response patterns in selected aerobic fitness variables of regular starters (ST; N = 7) and non-starters (Non-ST; N = 10), top level professional soccer players were tested for maximal oxygen uptake (VO2max), velocity at 4 mM of lactate (V4), velocity at maximal oxygen uptake (νVO2max) and oxygen pulse (O2-pulse) in July and December following consecutive periods of fixture congestion. V4 was the only variable that increased significantly in December compared to July (15.1 ± 0.5 vs. 14.6 ± 0.5, p = 0.001). There was an almost certain beneficial large mean team change for V4 (ES = 1.2 (0.67; 1.57), 100/0/0), while beneficial mean team changes were less likely for νVO2max and O2-pulse [ES = 0.31 (-0.08; 0.70), 68/30/2 and ES = 0.24 (0.01; 0.49), 64/36/0, respectively] and unclear for VO2max (ES = 0.02 (-0.31; 0.70), 18/69/13). With the exception of V4 where 10 out of 17 players (7 ST and 3 Non-ST) showed positive changes higher than the biological variability, all other variables were characterized by a substantial proportion of changes lower than the biological variability. The present study demonstrated that aerobic fitness variables that require maximal effort may be characterized by greater variability of the individual response pattern compared to that of submaximal aerobic fitness variables irrespective of the accumulated game time. Submaximal aerobic fitness variables appear to be more informative in the physiological evaluation of top level soccer players and this may be an advantage during exposure to periods of consecutive games. PMID:29599863

Factors affecting variability in the urinary biomarker 1,6-hexamethylene diamine in workers exposed to 1,6-hexamethylene diisocyanate.

PubMed

Gaines, Linda G T; Fent, Kenneth W; Flack, Sheila L; Thomasen, Jennifer M; Whittaker, Stephen G; Nylander-French, Leena A

2011-01-01

Although urinary 1,6-hexamethylene diamine (HDA) is a useful biomarker of exposure to 1,6-hexamethylene diisocyanate (HDI), a large degree of unexplained intra- and inter-individual variability exists between estimated HDI exposure and urine HDA levels. We investigated the effect of individual and workplace factors on urine HDA levels using quantitative dermal and inhalation exposure data derived from a survey of automotive spray painters exposed to HDI. Painters' dermal and breathing-zone HDI-exposures were monitored over an entire workday for up to three separate workdays, spaced approximately one month apart. One urine sample was collected before the start of work with HDI-containing paints, and multiple samples were collected throughout the workday. Using mixed effects multiple linear regression modeling, coverall use resulted in significantly lower HDA levels (p = 0.12), and weekday contributed to significant variability in HDA levels (p = 0.056). We also investigated differences in urine HDA levels stratified by dichotomous and classification covariates using analysis of variance. Use of coveralls (p = 0.05), respirator type worn (p = 0.06), smoker status (p = 0.12), paint-booth type (p = 0.02), and more than one painter at the shop (p = 0.10) were all found to significantly affect urine HDA levels adjusted for creatinine concentration. Coverall use remained significant (p = 0.10), even after adjusting for respirator type. These results indicate that the variation in urine HDA level is mainly due to workplace factors and that appropriate dermal and inhalation protection is required to prevent HDI exposure.

Heart Rate Variability during Simulated Hemorrhage with Lower Body Negative Pressure in High and Low Tolerant Subjects.

PubMed

Hinojosa-Laborde, Carmen; Rickards, Caroline A; Ryan, Kathy L; Convertino, Victor A

2011-01-01

Heart rate variability (HRV) decreases during hemorrhage, and has been proposed as a new vital sign to assess cardiovascular stability in trauma patients. The purpose of this study was to determine if any of the HRV metrics could accurately distinguish between individuals with different tolerance to simulated hemorrhage. Specifically, we hypothesized that (1) HRV would be similar in low tolerant (LT) and high tolerant (HT) subjects at presyncope when both groups are on the verge of hemodynamic collapse; and (2) HRV could distinguish LT subjects at presyncope from hemodynamically stable HT subjects (i.e., at a submaximal level of hypovolemia). Lower body negative pressure (LBNP) was used as a model of hemorrhage in healthy human subjects, eliciting central hypovolemia to the point of presyncopal symptoms (onset of hemodynamic collapse). Subjects were classified as LT if presyncopal symptoms occurred during the -15 to -60 mmHg levels of LBNP, and HT if symptoms occurred after LBNP of -60 mmHg. A total of 20 HRV metrics were derived from R-R interval measurements at the time of presyncope, and at one level prior to presyncope (submax) in LT and HT groups. Only four HRV metrics (Long-range Detrended Fluctuation Analysis, Forbidden Words, Poincaré Plot Descriptor Ratio, and Fractal Dimensions by Curve Length) supported both hypotheses. These four HRV metrics were evaluated further for their ability to identify individual LT subjects at presyncope when compared to HT subjects at submax. Variability in individual LT and HT responses was so high that LT responses overlapped with HT responses by 85-97%. The sensitivity of these HRV metrics to distinguish between individual LT from HT subjects was 6-33%, and positive predictive values were 40-73%. These results indicate that while a small number of HRV metrics can accurately distinguish between LT and HT subjects using group mean data, individual HRV values are poor indicators of tolerance to hypovolemia.

[Level of funding in the Long-Term Care Law: the cost of moving toward real dependency variables].

PubMed

Correa Gómez, Manuel; Montero Granados, Roberto; Jiménez Aguilera, Juan de Dios

2011-12-01

The system for the Promotion of Personal Autonomy and Care of Dependent Persons established by Act 39/2006 is funded through private contributions of dependent individuals and earmarked transfers in three main funds: a minimum level, an agreed level distributed among the various autonomous regions according to their relative needs, and a further voluntary additional contribution by Spain's autonomous regions. The resources distributed by the state to the regions are assigned, among other less important variables, according to the potentially dependent population and, to a lesser extent, according to the population already evaluated as dependent. Because the concept of what constitutes disability has changed over the years from the population potentially dependent according to an estimate (estimated dependent individuals) to the actual number of dependent individuals recognized as such (declared dependent), some autonomous regions may have been overfunded or underfunded. The funding obtained by the autonomous regions each year from 2007 to 2011 was compared with the funding that would have been assigned to each region if, since 2007, the variables and weighting that will be representative of the funding needs for 2013 (distribution mainly according to declared dependent individuals) had been taken into account. From 2007-2011, regions where declared dependent persons outnumbered estimated disabled persons were underfunded (in Andalusia by more than 100 million euros). In contrast, regions where the situation was reversed were overfunded (by 49 million euros in Madrid and 37 million euros in the region of Valencia). There is wide variation in public funding to the autonomous regions, depending on the number of individuals declared as dependent. Among other no less serious consequences, this situation could hamper the implantation of the Promotion of Personal Autonomy and Care of Dependent Persons Act in underfunded regions. Copyright © 2011 SESPAS. Published by Elsevier Espana. All rights reserved.

Analysis of cognitive variables and sexual risk behaviors among infected and HIV-uninfected people from Spain.

PubMed

Bermúdez, María de la Paz; Araújo, Ludgleydson Fernandes de; Reyes, Antonio Ortega; Hernández-Quero, José; Teva, Inmaculada

2016-07-01

The wider availability of anti-retroviral treatment has brought about an improvement in the immunological situation of human immunodeficiency virus (HIV)-positive individuals, which in turn has led to significant reductions in AIDS-related morbidity and mortality and better quality of life for patients. However, the rate of diagnosis of new cases of HIV among the adult population is on the increase due to high-risk sexual behavior practices, particularly not using condoms, sexual relations with a large number of partners and starting sexual relations at a younger age, with unplanned pregnancies and sexually transmitted infections (STIs), including HIV. For this reason, public health managers have invested considerable effort in recent years in creating STI and HIV prevention programs. Yet, in spite of the implementation of measures for reducing the rates of infection, few studies have been published in Spain comparing individuals living with HIV with the general population about cognitive variables and the link between these variables and high-risk sexual behavior. The objective was to compare a group of individuals living with HIV with another group from the general population in terms of cognitive variables (knowledge about STIs and HIV, concern about STI/HIV and pregnancy, self-efficacy to refuse sexual relations and resilience) and sexual behavior. The sample consisted of 318 adults, 159 were from the general population and 159 were individuals living with HIV. Individuals living with HIV had higher scores for concern about HIV/AIDS, STIs, pregnancy and knowledge of STI/HIV compared with the general population. We concluded that uninfected people who had low and high level of concern about HIV/AIDS began having anal sex at a younger age than those with a medium level of concern. Overall, results indicate that the concern about HIV/AIDS should be addressed in preventive health interventions to minimize the risks of sexual behavior.

Essentials of psychoanalytic process and change: how can we investigate the neural effects of psychodynamic psychotherapy in individualized neuro-imaging?

PubMed Central

Boeker, Heinz; Richter, André; Himmighoffen, Holger; Ernst, Jutta; Bohleber, Laura; Hofmann, Elena; Vetter, Johannes; Northoff, Georg

2013-01-01

The paper focuses on the essentials of psychoanalytic process and change and the question of how the neural correlates and mechanisms of psychodynamic psychotherapy can be investigated. The psychoanalytic approach aims at enabling the patient to “remember, repeat, and work through” concerning explicit memory. Moreover, the relationship between analyst and patient establishes a new affective configuration which enables a reconstruction of the implicit memory. If psychic change can be achieved it corresponds to neuronal transformation. Individualized neuro-imaging requires controlling and measuring of variables that must be defined. Two main methodological problems can be distinguished: the design problem addresses the issue of how to account for functionally related variables in an experimentally independent way. The translation problem raises the question of how to bridge the gaps between different levels of the concepts presupposed in individualized neuro-imaging (e.g., the personal level of the therapist and the client, the neural level of the brain). An overview of individualized paradigms, which have been used until now is given, including Operationalized Psychodynamic Diagnosis (OPD-2) and the Maladaptive Interpersonal Patterns Q-Start (MIPQS). The development of a new paradigm that will be used in fMRI experiments, the “Interpersonal Relationship Picture Set” (IRPS), is described. Further perspectives and limitations of this new approach concerning the design and the translation problem are discussed. PMID:23935571

The effect of clumped population structure on the variability of spreading dynamics.

PubMed

Black, Andrew J; House, Thomas; Keeling, Matt J; Ross, Joshua V

2014-10-21

Processes that spread through local contact, including outbreaks of infectious diseases, are inherently noisy, and are frequently observed to be far noisier than predicted by standard stochastic models that assume homogeneous mixing. One way to reproduce the observed levels of noise is to introduce significant individual-level heterogeneity with respect to infection processes, such that some individuals are expected to generate more secondary cases than others. Here we consider a population where individuals can be naturally aggregated into clumps (subpopulations) with stronger interaction within clumps than between them. This clumped structure induces significant increases in the noisiness of a spreading process, such as the transmission of infection, despite complete homogeneity at the individual level. Given the ubiquity of such clumped aggregations (such as homes, schools and workplaces for humans or farms for livestock) we suggest this as a plausible explanation for noisiness of many epidemic time series. Copyright © 2014 Elsevier Ltd. All rights reserved.

Association of genetic and phenotypic variability with geography and climate in three southern California oaks.

PubMed

Riordan, Erin C; Gugger, Paul F; Ortego, Joaquín; Smith, Carrie; Gaddis, Keith; Thompson, Pam; Sork, Victoria L

2016-01-01

Geography and climate shape the distribution of organisms, their genotypes, and their phenotypes. To understand historical and future evolutionary and ecological responses to climate, we compared the association of geography and climate of three oak species (Quercus engelmannii, Quercus berberidifolia, and Quercus cornelius-mulleri) in an environmentally heterogeneous region of southern California at three organizational levels: regional species distributions, genetic variation, and phenotypic variation. We identified climatic variables influencing regional distribution patterns using species distribution models (SDMs), and then tested whether those individual variables are important in shaping genetic (microsatellite) and phenotypic (leaf morphology) variation. We estimated the relative contributions of geography and climate using multivariate redundancy analyses (RDA) with variance partitioning. The modeled distribution of each species was influenced by climate differently. Our analysis of genetic variation using RDA identified small but significant associations between genetic variation with climate and geography in Q. engelmannii and Q. cornelius-mulleri, but not in Q. berberidifolia, and climate explained more of the variation. Our analysis of phenotypic variation in Q. engelmannii indicated that climate had more impact than geography, but not in Q. berberidifolia. Throughout our analyses, we did not find a consistent pattern in effects of individual climatic variables. Our comparative analysis illustrates that climate influences tree response at all organizational levels, but the important climate factors vary depending on the level and on the species. Because of these species-specific and level-specific responses, today's sympatric species are unlikely to have similar distributions in the future. © 2016 Botanical Society of America.

Biomechanical deviations during level walking associated with knee osteoarthritis: a systematic review and meta-analysis.

PubMed

Mills, Kathryn; Hunt, Michael A; Ferber, Reed

2013-10-01

To identify which gait deviations are consistently associated with knee osteoarthritis (KOA) and how these are influenced by disease severity, the involved compartment, and sex. Five electronic databases and reference lists of publications were searched. Cross-sectional, observational studies comparing temporospatial variables, joint kinematics, and joint moments between individuals with KOA and healthy controls or between KOA subgroups were considered for review. Only publications scoring ≥50% on a modified methodology quality index were included. Because of the number of gait deviations examined, only biomechanical variables reported by ≥4 publications were further analyzed. Where possible, a meta-analysis was performed using effect sizes (ES) calculated from discrete variables. In total, 41 publications examining 20 variables were included. The majority of consistent gait deviations associated with KOA were exhibited by those with severe disease in the temporospatial domain. Individuals with severe KOA exhibited greater stride duration than controls (ES 1.35 [95% confidence interval (95% CI) 1.03, 1.67]) and a decrease in cadence (ES -0.75 [95% CI -1.12, -0.39]) compared with controls. The evidence for kinematic and joint moment change was primarily limited or conflicting. There was a lack of evidence for alterations in the external knee adduction moment. Individuals with KOA exhibit a range of gait deviations compared with controls. Despite its common usage in KOA gait studies, we did not find consistent evidence that knee adduction moment differs between those with and without KOA or between disease severity levels. Further research examining the reasons for a lack of difference in many gait variables in those with knee OA is needed. Copyright © 2013 by the American College of Rheumatology.

Dopaminergic modulation of hemodynamic signal variability and the functional connectome during cognitive performance.

PubMed

Alavash, Mohsen; Lim, Sung-Joo; Thiel, Christiane; Sehm, Bernhard; Deserno, Lorenz; Obleser, Jonas

2018-05-15

Dopamine underlies important aspects of cognition, and has been suggested to boost cognitive performance. However, how dopamine modulates the large-scale cortical dynamics during cognitive performance has remained elusive. Using functional MRI during a working memory task in healthy young human listeners, we investigated the effect of levodopa (l-dopa) on two aspects of cortical dynamics, blood oxygen-level-dependent (BOLD) signal variability and the functional connectome of large-scale cortical networks. We here show that enhanced dopaminergic signaling modulates the two potentially interrelated aspects of large-scale cortical dynamics during cognitive performance, and the degree of these modulations is able to explain inter-individual differences in l-dopa-induced behavioral benefits. Relative to placebo, l-dopa increased BOLD signal variability in task-relevant temporal, inferior frontal, parietal and cingulate regions. On the connectome level, however, l-dopa diminished functional integration across temporal and cingulo-opercular regions. This hypo-integration was expressed as a reduction in network efficiency and modularity in more than two thirds of the participants and to different degrees. Hypo-integration co-occurred with relative hyper-connectivity in paracentral lobule and precuneus, as well as posterior putamen. Both, l-dopa-induced BOLD signal variability modulation and functional connectome modulations proved predictive of an individual's l-dopa-induced benefits in behavioral performance, namely response speed and perceptual sensitivity. Lastly, l-dopa-induced modulations of BOLD signal variability were correlated with l-dopa-induced modulation of nodal connectivity and network efficiency. Our findings underline the role of dopamine in maintaining the dynamic range of, and communication between, cortical systems, and their explanatory power for inter-individual differences in benefits from dopamine during cognitive performance. Copyright © 2018 Elsevier Inc. All rights reserved.

Comparison of propranolol and metoprolol in the management of hyperthyroidism.

PubMed Central

Murchison, L E; How, J; Bewsher, P D

1979-01-01

1 Propranolol and metoprolol were both effective in controlling the symptoms and signs of hyperthyroidism. 2 Propranolol caused a highly significant increase in serum reverse T3 concentrations with lesser changes in other serum thyroid hormone levels, whereas metoprolol did not have this effect. 3 Steady-state plasma propranolol and metoprolol levels showed marked inter-individual variation. Metoprolol concentrations showed relatively little intra-individual variability, and could be related to the clinical efficacy of the drug, whereas no such relationship was demonstrated for propranolol. PMID:391258

Cognitive inconsistency in bipolar patients is determined by increased intra-individual variability in initial phase of task performance.

PubMed

Krukow, Paweł; Szaniawska, Ola; Harciarek, Michał; Plechawska-Wójcik, Małgorzata; Jonak, Kamil

2017-03-01

Bipolar patients show high intra-individual variability during cognitive processing. However, it is not known whether there are a specific fluctuations of variability contributing to the overall high cognitive inconsistency. The objective was to compare dynamic profiles of patients and healthy controls to identify hypothetical differences and their associations with overall variability and processing speed. Changes of reaction times iSD during processing speed test performance over time was measured by dividing the iSD for whole task into four consecutive parts. Motor speed and cognitive effort were controlled. Patients with BD exhibited significantly lower results regarding processing speed and higher intra-individual variability comparing with HC. The profile of intra-individual variability changes over time of performance was significantly different in BD versus HC groups: F(3, 207)=8.60, p<0.0001, η p 2 =0.11. iSD of BD patients in the initial phase of performance was three times higher than in the last. There was no significant differences between four intervals in HC group. Inter-group difference in the initial part of the profiles was significant also after controlling for several cognitive and clinical variables. Applied computer version of Cognitive Speed Test was relatively new and, thus, replication studies are needed. Effect seen in the present study is driven mainly by the BD type I. Patients with BD exhibits problems with setting a stimulus-response association in starting phase of cognitive processing. This deficit may negatively interfere with the other cognitive functions, decreasing level of psychosocial functioning, therefore should be explored in future studies. Copyright © 2017 Elsevier B.V. All rights reserved.

Russell body inducing threshold depends on the variable domain sequences of individual human IgG clones and the cellular protein homeostasis.

PubMed

Stoops, Janelle; Byrd, Samantha; Hasegawa, Haruki

2012-10-01

Russell bodies are intracellular aggregates of immunoglobulins. Although the mechanism of Russell body biogenesis has been extensively studied by using truncated mutant heavy chains, the importance of the variable domain sequences in this process and in immunoglobulin biosynthesis remains largely unknown. Using a panel of structurally and functionally normal human immunoglobulin Gs, we show that individual immunoglobulin G clones possess distinctive Russell body inducing propensities that can surface differently under normal and abnormal cellular conditions. Russell body inducing predisposition unique to each immunoglobulin G clone was corroborated by the intrinsic physicochemical properties encoded in the heavy chain variable domain/light chain variable domain sequence combinations that define each immunoglobulin G clone. While the sequence based intrinsic factors predispose certain immunoglobulin G clones to be more prone to induce Russell bodies, extrinsic factors such as stressful cell culture conditions also play roles in unmasking Russell body propensity from immunoglobulin G clones that are normally refractory to developing Russell bodies. By taking advantage of heterologous expression systems, we dissected the roles of individual subunit chains in Russell body formation and examined the effect of non-cognate subunit chain pair co-expression on Russell body forming propensity. The results suggest that the properties embedded in the variable domain of individual light chain clones and their compatibility with the partnering heavy chain variable domain sequences underscore the efficiency of immunoglobulin G biosynthesis, the threshold for Russell body induction, and the level of immunoglobulin G secretion. We propose that an interplay between the unique properties encoded in variable domain sequences and the state of protein homeostasis determines whether an immunoglobulin G expressing cell will develop the Russell body phenotype in a dynamic cellular setting. Copyright © 2012 Elsevier B.V. All rights reserved.

Increased Force Variability in Chronic Stroke: Contributions of Force Modulation below 1 Hz

PubMed Central

Lodha, Neha; Misra, Gaurav; Coombes, Stephen A.; Christou, Evangelos A.; Cauraugh, James H.

2013-01-01

Increased force variability constitutes a hallmark of arm disabilities following stroke. Force variability is related to the modulation of force below 1 Hz in healthy young and older adults. However, whether the increased force variability observed post stroke is related to the modulation of force below 1 Hz remains unknown. Thus, the purpose of this study was to compare force modulation below 1 Hz in chronic stroke and age-matched healthy individuals. Both stroke and control individuals (N = 26) performed an isometric grip task to submaximal force levels. Coefficient of variation quantified force variability, and power spectrum density of force quantified force modulation below 1 Hz with a high resolution (0.07 Hz). Analyses indicated that force variability was greater for the stroke group compared with to healthy controls and for the paretic hand compared with the non-paretic hand. Force modulation below 1 Hz differentiated the stroke individuals and healthy controls, as well as the paretic and non-paretic hands. Specifically, stroke individuals (paretic hand) exhibited greater power ∼0.2 Hz (0.07–0.35 Hz) and lesser power ∼0.6 Hz (0.49–0.77 Hz) compared to healthy controls (non-dominant hand). Similarly, the paretic hand exhibited greater power ∼0.2 Hz, and lesser power ∼0.6 Hz than the non-paretic hand. Moreover, variability of force was strongly predicted from the modulation of specific frequencies below 1 Hz (R 2 = 0.80). Together, these findings indicate that the modulation of force below 1 Hz provides significant insight into changes in motor control after stroke. PMID:24386208

Affective Balance, Team Prosocial Efficacy and Team Trust: A Multilevel Analysis of Prosocial Behavior in Small Groups

PubMed Central

Cuadrado, Esther; Tabernero, Carmen

2015-01-01

Little research has focused on how individual- and team-level characteristics jointly influence, via interaction, how prosocially individuals behave in teams and few studies have considered the potential influence of team context on prosocial behavior. Using a multilevel perspective, we examined the relationships between individual (affective balance) and group (team prosocial efficacy and team trust) level variables and prosocial behavior towards team members. The participants were 123 students nested in 45 small teams. A series of multilevel random models was estimated using hierarchical linear and nonlinear modeling. Individuals were more likely to behave prosocially towards in-group members when they were feeling good. Furthermore, the relationship between positive affective balance and prosocial behavior was stronger in teams with higher team prosocial efficacy levels as well as in teams with higher team trust levels. Finally, the relevance of team trust had a stronger influence on behavior than team prosocial efficacy. PMID:26317608

Intraindividual variability in cognitive performance in persons with chronic fatigue syndrome.

PubMed

Fuentes, K; Hunter, M A; Strauss, E; Hultsch, D F

2001-05-01

Studies of cognitive performance among persons with chronic fatigue syndrome (CFS) have yielded inconsistent results. We sought to contribute to findings in this area by examining intraindividual variability as well as level of performance in cognitive functioning. A battery of cognitive measures was administered to 14 CFS patients and 16 healthy individuals on 10 weekly occasions. Analyses comparing the two groups in terms of level of performance defined by latency and accuracy scores revealed that the CFS patients were slower but not less accurate than healthy persons. The CFS group showed greater intraindividual variability (as measured by intraindividual standard deviations and coefficients of variation) than the healthy group, although the results varied by task and time frame. Intraindividual variability was found to be stable across time and correlated across tasks at each testing occasion. Intraindividual variability also uniquely differentiated the groups. The present findings support the proposition that intraindividual variability is a meaningful indicator of cognitive functioning in CFS patients.

Adherence to physical activity in an unsupervised setting: Explanatory variables for high attrition rates among fitness center members.

PubMed

Sperandei, Sandro; Vieira, Marcelo C; Reis, Arianne C

2016-11-01

To evaluate the attrition rate of members of a fitness center in the city of Rio de Janeiro and the potential explanatory variables for the phenomenon. An exploratory, observational study using a retrospective longitudinal frame. The records of 5240 individuals, members of the fitness center between January-2005 and June-2014, were monitored for 12 months or until cancellation of membership, whichever occurred first. A Cox proportional hazard regression model was adjusted to identify variables associated to higher risk of 'abandonment' of activities. This study was approved by Southern Cross University's Human Research Ethics Committee (approval number: ECN-15-176). The general survival curve shows that 63% of new members will abandon activities before the third month, and less than 4% will remain for more than 12 months of continuous activity. The regression model showed that age, previous level of physical activity, initial body mass index and motivations related to weight loss, hypertrophy, health, and aesthetics are related to risk of abandonment. Combined, those variables represent an important difference in the probability to abandon the gym between individuals with the best and worse combination of variables. Even individuals presenting the best combination of variables still present a high risk of abandonment before completion of 12 months of fitness center membership. Findings can assist in the identification of high risk individuals and therefore help in the development of strategies to prevent abandonment of physical activity practice. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Beyond Trisomy 21: Phenotypic Variability in People with Down Syndrome Explained by Further Chromosome Mis-segregation and Mosaic Aneuploidy

PubMed Central

Potter, Huntington

2017-01-01

Phenotypic variability is a fundamental feature of the human population and is particularly evident among people with Down syndrome and/or Alzheimer’s disease. Herein, we review current theories of the potential origins of this phenotypic variability and propose a novel mechanism based on our finding that the Alzheimer’s disease-associated Aβ peptide, encoded on chromosome 21, disrupts the mitotic spindle, induces abnormal chromosome segregation, and produces mosaic populations of aneuploid cells in all tissues of people with Alzheimer’s disease and in mouse and cell models thereof. Thus, individuals exposed to increased levels of the Aβ peptide should accumulate mosaic populations of aneuploid cells, with different chromosomes affected in different tissues and in different individuals. Specifically, people with Down syndrome, who express elevated levels of Aβ peptide throughout their lifetimes, would be predicted to accumulate additional types of aneuploidy, beyond trisomy 21 and including changes in their trisomy 21 status, in mosaic cell populations. Such mosaic aneuploidy would introduce a novel form of genetic variability that could potentially underlie much of the observed phenotypic variability among people with Down syndrome, and possibly also among people with Alzheimer’s disease. This mosaic aneuploidy theory of phenotypic variability in Down syndrome is supported by several observations, makes several testable predictions, and identifies a potential approach to reducing the frequency of some of the most debilitating features of Down syndrome, including Alzheimer’s disease. PMID:29516054

Evaluation of Variable-Depth Liner Configurations for Increased Broadband Noise Reduction

NASA Technical Reports Server (NTRS)

Jones, M. G.; Watson, W. R.; Nark, D. M.; Howerton, B. M.

2015-01-01

This paper explores the effects of variable-depth geometry on the amount of noise reduction that can be achieved with acoustic liners. Results for two variable-depth liners tested in the NASA Langley Grazing Flow Impedance Tube demonstrate significant broadband noise reduction. An impedance prediction model is combined with two propagation codes to predict corresponding sound pressure level profiles over the length of the Grazing Flow Impedance Tube. The comparison of measured and predicted sound pressure level profiles is sufficiently favorable to support use of these tools for investigation of a number of proposed variable-depth liner configurations. Predicted sound pressure level profiles for these proposed configurations reveal a number of interesting features. Liner orientation clearly affects the sound pressure level profile over the length of the liner, but the effect on the total attenuation is less pronounced. The axial extent of attenuation at an individual frequency continues well beyond the location where the liner depth is optimally tuned to the quarter-wavelength of that frequency. The sound pressure level profile is significantly affected by the way in which variable-depth segments are distributed over the length of the liner. Given the broadband noise reduction capability for these liner configurations, further development of impedance prediction models and propagation codes specifically tuned for this application is warranted.

Long-Term Monitoring of Regional Sea Surface Height Variability Using High-Resolution Satellite Altimetry

NASA Astrophysics Data System (ADS)

Rice, A. E.; Crout, R. L.

2017-12-01

Shallow water altimetry is an emerging field that in recent years has rapidly gained attention for both the numerous applications it can offer to the oceanographic community (e.g. assessment of climate change impacts to the coastal zone; quantification of sea state etc.) and, depending on the altimeter used, for the wealth of available historical data that can be employed for climatological studies. In this study we focus on the long-term analysis of regional sea surface height anomaly (SSHA) variability over the mid and outer shelf (≥ 16 km from the coast) for 18 selected coastal altimeter tracks located on the east coast of the US and Asia for a period of eight years (294 passes from July 2008 to July 2016) using Jason-2 20 Hz altimeter data from the L2 AVISO-PISTACH experimental products. After implementing geophysical corrections to the raw altimeter range, signal noise in the individual SSH passes was reduced by applying a median filter followed by a 60-point (18 km) low-pass filter as in Birol and Delebeque (2014). Since individual altimeter passes did not cease to collect data at the same distance from the coastline, a nearest-point-to-land (NPTL) was determined for each track for statistical analysis of the data. NPTL time series and SSHA envelopes, computed by subtracting mean SSHAs from individual passes, were used for the analysis. A comparison of wind and water level gauge data to a US east coast track reveals correlation between SSHA and winds and a relationship to subtidal water level frequencies. Time series of NPTL for all tracks show intra-annual and inter and intra-seasonal variability, with higher and lower water levels linked to seasons. Lastly, envelope plots display higher SSHA variability over the mid shelf than the outer shelf, revealing the location and magnitude (up to 0.5 m water level differences) of setup and set down occurrences. Various products derived from the analysis that are useful for oceanographic operations, including water level change percentages and width of coastal boundary layers, are discussed.

Trading Sex for Money or Compensation: Prevalence and Associated Characteristics from a Sexually Transmitted Infection (STI) Clinic Sample.

PubMed

Gerassi, Lara B; Jonson-Reid, Melissa; Plax, Katie; Kaushik, Gaurav

2016-01-01

The purpose of this study was to determine the prevalence and individual risk factors of people who trade or sell sex among sexually active individuals seeking HIV and sexually transmitted infection (STI) testing. Using electronic agency records, an analysis of the characteristics of 5,029 youth and adults who voluntarily obtained HIV and STI testing was conducted. Multiple imputation procedures for missing data from 3 variables and logistic regression were conducted. A total of 128 individuals reported having traded sex. Nine variables had statistically significant associations with trading sex. Individuals who identified as White and female had lesser odds of trading sex, whereas individuals who were transgender, were living in a shelter, had been sexually assaulted, had a previous STI, had high-risk sex, or used drugs had greater odds of trading sex. Elevated levels of high-risk behavior in addition to sexual trauma should be considered in intervention research and community health practice. Implications for service providers and researchers are discussed.

A matter of hand: Causal links between hand dominance, structural organization of fronto-parietal attention networks, and variability in behavioural responses to transcranial magnetic stimulation.

PubMed

Cazzoli, Dario; Chechlacz, Magdalena

2017-01-01

Considerable evidence suggests that, on a group level, human visuospatial attention is asymmetrically organized, with a right-hemispheric dominance. The asymmetrical organization of the superior longitudinal fasciculus (SLF) has been shown to account for the right-hemispheric dominance in visual attention. However, such account is by no means universal, and large individual differences in asymmetrical performance on visuospatial tasks have been reported. Furthermore, the variability in the SLF lateralization has been shown to correlate with behavioural asymmetries. Continuous theta burst stimulation (cTBS) enables to temporarily interfere with cortical activity. cTBS applied over the posterior parietal cortex (PPC) has been previously used to systematically study attentional asymmetries. Interestingly, large individual differences in the effectiveness of stimulation have been reported. In accordance with earlier both animal and human studies, one possible cause underlying these striking individual differences might lie in the structural organization of frontoparietal pathways subserving visuospatial attention. Thus, the current study employed diffusion tractography to examine the relationship between the variability in the structural organization of the SLF and the individual differences in attentional shifts induced by a modified cTBS (cTBS mod ; triplets of pulses at 30 Hz, repeated at 6 Hz) applied over the IPS, as measured by a line bisection task. Consistent with previous studies, on a group level, cTBS mod applied over the right intraparietal sulcus (IPS) triggered a rightward bisection bias shift, and there were no significant effects of cTBS mod applied over the left IPS. However, further analyses demonstrated that both handedness and structural variability (as assessed based on hindrance modulated orientational anisotropy) within the middle and the ventral branches of the SLF predicted individual differences in the cTBS mod -induced attentional shifts. Our study thus suggests that the effects of cTBS mod over the IPS may depend on intra-hemispheric interactions between cortical loci controlling visual attention. To conclude, our findings provide converging evidence for the notion put forward previously that inter-individual variability in the structural organization of intra-hemispheric frontoparietal connections has important implications for the functional models of human visual attention. Moreover, we hypothesize that this may also be relevant for the understanding of attentional disorders and their rehabilitation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Interindividual Differences in Caffeine Metabolism and Factors Driving Caffeine Consumption.

PubMed

Nehlig, Astrid

2018-04-01

Most individuals adjust their caffeine intake according to the objective and subjective effects induced by the methylxanthine. However, to reach the desired effects, the quantity of caffeine consumed varies largely among individuals. It has been known for decades that the metabolism, clearance, and pharmacokinetics of caffeine is affected by many factors such as age, sex and hormones, liver disease, obesity, smoking, and diet. Caffeine also interacts with many medications. All these factors will be reviewed in the present document and discussed in light of the most recent data concerning the genetic variability affecting caffeine levels and effects at the pharmacokinetic and pharmacodynamic levels that both critically drive the level of caffeine consumption. The pharmacokinetics of caffeine are highly variable among individuals due to a polymorphism at the level of the CYP1A2 isoform of cytochrome P450, which metabolizes 95% of the caffeine ingested. Moreover there is a polymorphism at the level of another critical enzyme, N -acetyltransferase 2. At the pharmacodynamic level, there are several polymorphisms at the main brain target of caffeine, the adenosine A2A receptor or ADORA2. Genetic studies, including genome-wide association studies, identified several loci critically involved in caffeine consumption and its consequences on sleep, anxiety, and potentially in neurodegenerative and psychiatric diseases. We start reaching a better picture on how a multiplicity of biologic mechanisms seems to drive the levels of caffeine consumption, although much more knowledge is still required to understand caffeine consumption and effects on body functions. Copyright © 2018 by The American Society for Pharmacology and Experimental Therapeutics.

Can economic deprivation protect health? Paradoxical multilevel effects of poverty on Hispanic children's wheezing.

PubMed

Collins, Timothy W; Kim, Young-an; Grineski, Sara E; Clark-Reyna, Stephanie

2014-08-06

Prior research suggests that economic deprivation has a generally negative influence on residents' health. We employ hierarchical logistic regression modeling to test if economic deprivation presents respiratory health risks or benefits to Hispanic children living in the City of El Paso (Texas, USA) at neighborhood- and individual-levels, and whether individual-level health effects of economic deprivation vary based on neighborhood-level economic deprivation. Data come from the US Census Bureau and a population-based survey of El Paso schoolchildren. The dependent variable is children's current wheezing, an established respiratory morbidity measure, which is appropriate for use with economically-deprived children with an increased likelihood of not receiving a doctor's asthma diagnosis. Results reveal that economic deprivation (measured based on poverty status) at both neighborhood- and individual-levels is associated with reduced odds of wheezing for Hispanic children. A sensitivity analysis revealed similar significant effects of individual- and neighborhood-level poverty on the odds of doctor-diagnosed asthma. Neighborhood-level poverty did not significantly modify the observed association between individual-level poverty and Hispanic children's wheezing; however, greater neighborhood poverty tends to be more protective for poor (as opposed to non-poor) Hispanic children. These findings support a novel, multilevel understanding of seemingly paradoxical effects of economic deprivation on Hispanic health.

Can Economic Deprivation Protect Health? Paradoxical Multilevel Effects of Poverty on Hispanic Children’s Wheezing

PubMed Central

Collins, Timothy W.; Kim, Young-an; Grineski, Sara E.; Clark-Reyna, Stephanie

2014-01-01

Prior research suggests that economic deprivation has a generally negative influence on residents’ health. We employ hierarchical logistic regression modeling to test if economic deprivation presents respiratory health risks or benefits to Hispanic children living in the City of El Paso (Texas, USA) at neighborhood- and individual-levels, and whether individual-level health effects of economic deprivation vary based on neighborhood-level economic deprivation. Data come from the US Census Bureau and a population-based survey of El Paso schoolchildren. The dependent variable is children’s current wheezing, an established respiratory morbidity measure, which is appropriate for use with economically-deprived children with an increased likelihood of not receiving a doctor’s asthma diagnosis. Results reveal that economic deprivation (measured based on poverty status) at both neighborhood- and individual-levels is associated with reduced odds of wheezing for Hispanic children. A sensitivity analysis revealed similar significant effects of individual- and neighborhood-level poverty on the odds of doctor-diagnosed asthma. Neighborhood-level poverty did not significantly modify the observed association between individual-level poverty and Hispanic children’s wheezing; however, greater neighborhood poverty tends to be more protective for poor (as opposed to non-poor) Hispanic children. These findings support a novel, multilevel understanding of seemingly paradoxical effects of economic deprivation on Hispanic health. PMID:25101769

School-based exposure to hazardous air pollutants and grade point average: A multi-level study.

PubMed

Grineski, Sara E; Clark-Reyna, Stephanie E; Collins, Timothy W

2016-05-01

The problem of environmental health hazards around schools is serious but it has been neglected by researchers and analysts. This is concerning because children are highly susceptible to the effects of chemical hazards. Some ecological studies have demonstrated that higher school-level pollution is associated with lower aggregate school-level standardized test scores likely, related to increased respiratory illnesses and/or impaired cognitive development. However, an important question remains unexamined: How do school-level exposures impact individual children's academic performance? To address this, we obtained socio-demographic and grades data from the parents of 1888 fourth and fifth grade children in the El Paso (Texas, USA) Independent School District in 2012. El Paso is located on the US-side of the Mexican border and has a majority Mexican-origin population. School-based hazardous air pollution (HAP) exposure was calculated using census block-level US Environmental Protection Agency National Air Toxics Assessment risk estimates for respiratory and diesel particulate matter (PM). School-level demographics were obtained from the school district. Multi-level models adjusting for individual-level covariates (e.g., age, sex, race/ethnicity, English proficiency, and economic deprivation) and school-level covariates (e.g., percent of students economically disadvantaged and student-teacher ratio) showed that higher school-level HAPs were associated with lower individual-level grade point averages. An interquartile range increase in school-level HAP exposure was associated with an adjusted 0.11-0.40 point decrease in individual students' grade point averages (GPAs), depending on HAP type and emission source. Respiratory risk from HAPs had a larger effect on GPA than did diesel PM risk. Non-road mobile and total respiratory risk had the largest effects on children's GPA of all HAP variables studied and only mother's level of education had a larger effect than those two variables on children's GPA. The five school-level demographic indicators were only weakly associated with GPA. The study findings indicate the need for regulations on school siting and adjacent land uses to protect children's environmental health. Copyright © 2016 Elsevier Inc. All rights reserved.

Health profiles in people with intellectual developmental disorders.

PubMed

Folch-Mas, Anabel; Cortés-Ruiz, María José; Vicens Calderón, Paloma; Martínez-Leal, Rafael

2017-01-01

To better understand the health profiles of people with intellectual disability (ID), focusing on the variables that are associated with a poorer health status. Data were collected from the Survey on Disability, Personal Autonomy and Dependency (EDAD 2008) of the Spanish National Statistics Institute (INE). The health data of 2840 subjects with IDD were analyzed in order to verify the impact of different variables on their health profiles. People with severe and profound levels of IDD presented a higher number of medical diagnoses. At residence centers there was a larger proportion of individuals with a higher prevalence of chronic diseases and more severe conditions; age also was an important factor. The health profiles of individuals with IDD differ depending on the severity level of their IDD and their degree of institutionalization. Further research is needed to provide better health care for people with IDD.

The influence of individual and contextual work factors on workers' compliance with health and safety routines.

PubMed

Torp, Steffen; Grøgaard, Jens B

2009-03-01

This study investigated the relationships between workers' compliance with health and safety (H&S) routines and instructions adopted in the company (dependent variable) and psychological demands, decision authority, social support, management support, unionization and H&S management system (independent variables). A cross-sectional questionnaire study was performed among 1051 workers and the managers of 102 small- and medium-sized motor vehicle repair garages. Multilevel modeling was performed to account for the hierarchical structure of the data. At the worker level, high compliance with H&S routines correlated significantly with both social support and H&S-related management support. At the garage level, mean management support and a well-developed H&S management system correlated significantly with high workers' compliance. Changing both the individual and contextual factors in the work environment may thus increase workers' participation in H&S activities.

Cultural Variability in the Link Between Environmental Concern and Support for Environmental Action.

PubMed

Eom, Kimin; Kim, Heejung S; Sherman, David K; Ishii, Keiko

2016-10-01

Research on sustainability behaviors has been based on the assumption that increasing personal concerns about the environment will increase proenvironmental action. We tested whether this assumption is more applicable to individualistic cultures than to collectivistic cultures. In Study 1, we compared 47 countries ( N = 57,268) and found that they varied considerably in the degree to which environmental concern predicted support for proenvironmental action. National-level individualism explained the between-nation variability above and beyond the effects of other cultural values and independently of person-level individualism. In Study 2, we compared individualistic and collectivistic nations (United States vs. Japan; N = 251) and found culture-specific predictors of proenvironmental behavior. Environmental concern predicted environmentally friendly consumer choice among European Americans but not Japanese. For Japanese participants, perceived norms about environmental behavior predicted proenvironmental decision making. Facilitating sustainability across nations requires an understanding of how culture determines which psychological factors drive human action.

The role of family and school-level factors in bullying and cyberbullying: a cross-sectional study.

PubMed

Bevilacqua, Leonardo; Shackleton, Nichola; Hale, Daniel; Allen, Elizabeth; Bond, Lyndal; Christie, Deborah; Elbourne, Diana; Fitzgerald-Yau, Natasha; Fletcher, Adam; Jones, Rebecca; Miners, Alec; Scott, Stephen; Wiggins, Meg; Bonell, Chris; Viner, Russell M

2017-07-11

Bullying and cyberbullying are common phenomena in schools. These negative behaviours can have a significant impact on the health and particularly mental health of those involved in such behaviours, both as victims and as bullies. This UK study aims to investigate student-level and school-level characteristics of those who become involved in bullying and cyberbullying behaviours as victims or perpetrators. We used data from 6667 Year 7 students from the baseline survey of a cluster randomized trial in 40 English schools to investigate the associations between individual-level and school-level variables with bullying victimization, cyberbullying perpetration, and cyberbullying victimization. We ran multilevel models to examine associations of bullying outcomes with individual-level variables and school-level variables. In multilevel models, at the school level, school type and school quality measures were associated with bullying risk: students in voluntary-aided schools were less likely to report bullying victimization (0.6 (0.4, 0.9) p = 0.008), and those in community (3.9 (1.5, 10.5) p = 0.007) and foundation (4.0 (1.6, 9.9) p = 0.003) schools were more likely to report being perpetrators of cyberbullying than students in mainstream academies. A school quality rating of "Good" was associated with greater reported bullying victimization (1.3 (1.02, 1.5) p = 0.03) compared to ratings of "Outstanding." Bullying victimization and cyberbullying prevalence vary across school type and school quality, supporting the hypothesis that organisational/management factors within the school may have an impact on students' behaviour. These findings will inform future longitudinal research investigating which school factors and processes promote or prevent bullying and cyberbullying behaviours. Trial ID: ISRCTN10751359 Registered: 11/03/2014 (retrospectively registered).

Cyberbullying: The Discriminant Factors Among Cyberbullies, Cybervictims, and Cyberbully-Victims in a Czech Adolescent Sample.

PubMed

Bayraktar, Fatih; Machackova, Hana; Dedkova, Lenka; Cerna, Alena; Ševčíková, Anna

2015-11-01

Although the research on cyberbullying has increased dramatically in recent years, still little is known about how cyberbullying participant groups (i.e., cyberbullies, cybervictims, and cyberbully-victims) differ from one another. This study aims to discriminate between these groups at an individual and relational level by controlling for age and gender. Self-control, offline aggression, and self-esteem are analyzed as individual-level variables. Parental attachment and peer rejection are involved as relational-level variables. A total of 2,092 Czech adolescents aged 12 to 18 were enrolled from a random sample of 34 primary and secondary schools located in the South Moravian region of the Czech Republic. Discriminant function analyses indicated that the participant groups are discriminated by two functions. The first function increases the separation between cyberbullies and cyberbully-victims from cybervictims, indicating that cyberbullies and cyberbully-victims are similar to each other in terms of low self-control, offline aggression, and gender, and have higher scores on measures of low self-esteem and offline aggression. However, cyberbully-victims had the highest scores on these measures. The second function discriminates between all three groups, which indicates that those variables included in the second function (i.e., parental attachment, peer rejection, self-esteem, and age) distinguish all three involved groups. © The Author(s) 2014.

Effects of same-sex versus coeducational physical education on the self-perceptions of middle and high school students.

PubMed

Lirgg, C D

1993-09-01

The purpose of this field experiment was to investigate the effects of attending either a coeducational or a same-sex physical education class on several self-perception variables. Middle and high school youth who had previously been in coeducational classes were assigned to either a same-sex or a new coeducational physical education class for a 10-lesson unit of basketball. Analyses were conducted at both the group and the individual levels. Self-perception variables examined included perceived self-confidence of learning basketball, perceived usefulness of basketball, and perceived gender-appropriateness of basketball. Results of hierarchical linear model group level analyses indicated that the variability in groups for self-confidence could be explained by grade, class type, and the interaction between gender and class type. At the individual level, multivariate results showed that, after the unit, males in coeducational classes were significantly more confident in their ability to learn basketball than males in same-sex classes. Also, males in same-sex classes decreased in confidence from pretreatment to posttreatment. Perceived usefulness of basketball emerged as the strongest predictor of self-confidence for learning basketball for both genders. In general, middle school students preferred same-sex classes, whereas high school students preferred coeducational classes.

Inadequate child supervision: The role of alcohol outlet density, parent drinking behaviors, and social support

PubMed Central

Freisthler, Bridget; Johnson-Motoyama, Michelle; Kepple, Nancy J.

2014-01-01

Supervisory neglect, or the failure of a caregiver to appropriately supervise a child, is one of the predominant types of neglectful behaviors, with alcohol use being considered a key antecedent to inadequate supervision of children. The current study builds on previous work by examining the role of parental drinking and alcohol outlet densities while controlling for caregiver and child characteristics. Data were obtained from 3,023 participants via a telephone survey from 50 cities throughout California. The telephone survey included items on neglectful parenting practices, drinking behaviors, and socio-demographic characteristics. Densities of alcohol outlets were measured for each of the 202 zip codes in the study. Multilevel Bernoulli models were used to analyze the relationship between four supervisory neglect parenting practices and individual-level and zip code-level variables. In our study, heavy drinking was only significantly related to one of our four outcome variables (leaving a child where he or she may not be safe). The density of on premise alcohol outlets was positively related to leaving a child home alone when an adult should be present. This study demonstrates that discrete relationships exist between alcohol related variables, social support, and specific supervisory neglect subtypes at the ecological and individual levels. PMID:25061256

Accounting for test reliability in student progression: the reliable change index.

PubMed

Zahra, Daniel; Hedge, Craig; Pesola, Francesca; Burr, Steven

2016-07-01

Developed by Jacobson and Truax, the reliable change index (RCI) provides a measure of whether the change in an individual's score over time is within or beyond that which might be accounted for by measurement variability. In combination with measures of whether an individual's final score is closer to those of one population or another, this provides useful individual-level information that can be used to supplement traditional analyses. This article aims to highlight the potential of the RCI for use within medical education, particularly as a novel means of monitoring progress at the student level across successive test occasions or academic years. We provide an example of how the RCI can be applied informatively to assessment evaluation, and discuss its wider usage. The RCI approach can be used to identify and support failing students, as well as to determine best teaching and learning practices by identifying high-performing students. Furthermore, the individual-level nature of the RCI makes it well suited for educational research with small cohorts, as well as for tracking individual profiles within a larger cohort or addressing questions about individual performance that may be unanswerable at group level. © 2016 John Wiley & Sons Ltd.

Note on guilt appeals in advertising: covariate effects of self-esteem and locus of control.

PubMed

Pinto, M B; Worobetz, N D

1992-02-01

A 1991 study by Pinto and Priest demonstrated the effectiveness of advertisements employing moderate levels of guilt in inducing guilt responses in subjects. Because individuals' responses to guilt are often influenced by their specific personality characteristics, researchers have pointed to the potential moderating effects of individual difference variables such as level of self-esteem and locus of control on individuals' susceptibility to guilt appeals. A study was conducted to evaluate the possibility that self-esteem and locus of control can act as covariates across three treatment levels of guilt advertising. From a sample of 57 working mothers, advertisements stimulating medium and high levels of guilt elicited significantly greater feelings of guilt in subjects than the control advertisement stimulating low guilt. However, the relationship between susceptibility to guilt appeals and self-esteem and locus of control was not observed to covary.

The roles of unit leadership and nurse-physician collaboration on nursing turnover intention.

PubMed

Galletta, Maura; Portoghese, Igor; Battistelli, Adalgisa; Leiter, Michael P

2013-08-01

To report a study of the relationship between variables at the group and individual level with nurses' intention to leave their unit. Workplaces are collective environments where workers constantly interact with each other. The quality of working relationship employees develop at the unit-level influences both employee outcomes and unit performance by shaping employee attitudes. The study was a cross-sectional design with self-administered questionnaires. A questionnaire including measures of leader-member exchange and nurse-physician collaboration analysed at group-level and affective commitment and turnover intention analysed at individual level, was administered individually to 1018 nurses in five Italian hospitals. Data were collected in 2009. A total of 832 nurses (81·7% response rate) completed questionnaires. The results showed that affective commitment at individual level completely mediated the relationship between leader-member exchange at group-level and nursing turnover intention. Furthermore, the cross-level interaction was significant: at individual level, the nurses with high levels of individual affective commitment towards their unit showed low levels of turnover intention and this relationship was stronger when the nurse-physician collaboration at group-level was high. This study showed the importance for organizations to implement management practices that promote both high-quality nurse-supervisor and nurse-physician relationships, because they increase nurses' identification with their units. Individual affective commitment is an important quality for retaining a workforce and good nurses' relationship at group-level relationships with both supervisors and physicians are instrumental in developing identification with the work unit. Thus, the quality of relationship among staff members is an important factor in nurses' decision to leave. © 2012 Blackwell Publishing Ltd.

Language Shift in the United States and Foreign-Born Older Mexican Heritage Individuals: Co-Ethnic Context for Language Resistance

ERIC Educational Resources Information Center

Siordia, Carlos; Diaz, Maria E.

2012-01-01

In this study, we investigate individual-level language shift in a population of Mexican origin Latinos/as aged 65 and up. By using data from the Hispanic Established Populations for the Epidemiologic Study of the Elderly, we investigate their English language use as the dependent variable in a hierarchical linear model. The microlevel independent…

Cerebrospinal Fluid Biomarkers and Reserve Variables as Predictors of Future “Non-Cognitive” Outcomes of Alzheimer’s Disease

PubMed Central

Ingber, Adam P.; Hassenstab, Jason; Fagan, Anne M.; Benzinger, Tammie L.S.; Grant, Elizabeth A.; Holtzman, David M.; Morris, John C.; Roe, Catherine M.

2016-01-01

Background The influence of reserve variables and Alzheimer’s disease (AD) biomarkers on cognitive test performance has been fairly well-characterized. However, less is known about the influence of these factors on “non-cognitive” outcomes, including functional abilities and mood. Objective We examined whether cognitive and brain reserve variables mediate how AD biomarker levels in cognitively normal persons predict future changes in function, mood, and neuropsychiatric behavior. Methods Non-cognitive outcomes were examined in 328 individuals 50 years and older enrolled in ongoing studies of aging and dementia at the Knight Alzheimer Disease Research Center (ADRC). All participants were cognitively normal at baseline (Clinical Dementia Rating [CDR] 0), completed cerebrospinal fluid (CSF) and structural neuroimaging studies within one year of baseline, and were followed for an average of 4.6 annual visits. Linear mixed effects models explored how cognitive reserve and brain reserve variables mediate the relationships between AD biomarker levels and changes in function, mood, and neuropsychiatric behavior in cognitively normal participants. Results Education levels did not have a significant effect on predicting non-cognitive decline. However, participants with smaller brain volumes exhibited the worst outcomes on measures of mood, functional abilities, and behavioral disturbance. This effect was most pronounced in individuals who also had abnormal CSF biomarkers. Conclusions The findings suggest that brain reserve plays a stronger, or earlier, role than cognitive reserve in protecting against non-cognitive impairment in AD. PMID:27104893

Obesity and the community food environment: a systematic review.

PubMed

Holsten, Joanna E

2009-03-01

To examine the relationship between obesity and the community and/or consumer food environment. A comprehensive literature search of multiple databases was conducted and seven studies were identified for review. Studies were selected if they measured BMI and environmental variables related to food outlets. Environmental variables included the geographic arrangement of food stores or restaurants in communities and consumer conditions such as food price and availability within each outlet. The study designs, methods, limitations and results related to obesity and the food environment were reviewed, and implications for future research were synthesized. The reviewed studies used cross-sectional designs to examine the community food environment defined as the number per capita, proximity or density of food outlets. Most studies indirectly identified food outlets through large databases. The studies varied substantially in sample populations, outcome variables, units of measurement and data analysis. Two studies did not find any significant association between obesity rates and community food environment variables. Five studies found significant results. Many of the studies were subject to limitations that may have mitigated the validity of the results. Research examining obesity and the community or consumer food environment is at an early stage. The most pertinent gaps include primary data at the individual level, direct measures of the environment, studies examining the consumer environment and study designs involving a time sequence. Future research should directly measure multiple levels of the food environment and key confounders at the individual level.

Overweight and Obesity in Portuguese Children: Prevalence and Correlates

PubMed Central

Gomes, Thayse Natacha; Katzmarzyk, Peter T.; dos Santos, Fernanda K.; Souza, Michele; Pereira, Sara; Maia, José A. R.

2014-01-01

There are widespread differences in overweight/obesity prevalence in children, and understanding the reasons for this is very important. The present study aims: (I) to conduct a meta-analysis on overweight/obesity prevalence in Portuguese children; (II) to identify differences in biological and behavioural characteristics between normal-weight and overweight/obese children; and (III) to investigate the importance of individual- and school-level correlates of variation in children’s BMI using multilevel modelling. A search was done for all published papers including Portuguese children during the last decade; further, 686 Portuguese children (9–11 years old) were sampled and their BMI, family income, maturity offset, nutritional habits, physical activity, sedentariness, sleep time, and school environment information were collected. Results showed a stabilization of overweight/obesity during the last decade, 30.6% (95%CI: 0.287–0.34) for boys, 28.4% (95%CI: 0.23–0.35) for girls, and 30.3% (95%CI: 0.27–0.34) for boys and girls together. Differences between weight groups were only found in individual-level biological traits. The multilevel analysis did not identify significant contributions of school-level variables to children’s BMI variation. In conclusion, no increase was found in the prevalence of overweight/obesity among Portuguese children since 2000. Normal-weight and overweight/obese children only differ in individual-level characteristics, and school context variables were not related to variation in BMI. PMID:25372884

Genetic variability of an endangered Bromeliaceae species (Pitcairnia albiflos) from the Brazilian Atlantic rainforest.

PubMed

Domingues, R; Machado, M A; Forzza, R C; Melo, T D; Wohlres-Viana, S; Viccini, L F

2011-10-13

Pitcairnia albiflos is a Bromeliaceae species endemic to Brazil that has been included as data-deficient in the extinction risk list of Brazilian flora. We analyzed genetic variability in P. albiflos populations using RAPD markers to investigate population structure and reproductive mechanisms and also to evaluate the actual extinction risk level of this species. Leaves of 56 individuals of P. albiflos from three populations were collected: Urca Hill (UH, 20 individuals), Chacrinha State Park (CSP, 24 individuals) and Tijuca National Park (TNP, 12 individuals). The RAPD technique was effective in characterizing the genetic diversity in the P. albiflos populations since it was possible to differentiate the populations and to identify exclusive bands for at least two of them. Even if there is low genetic diversity among them (CSP-UH = 0.463; CSP-TNP = 0.440; UH-TNP = 0.524), the populations seem to be isolated according to the low genetic diversity observed within them (H(pop) CSP = 0.060; H(pop) UH = 0.042; H(pop) TNP = 0.130). This fact might be the result of clonal and self-reproduction predominance and also from environmental degradation around the collection areas. Consequently, it would be important to protect all populations both in situ and ex situ to prevent the decrease of genetic variability. The low genetic variability among individuals of the same population confirms the inclusion of this species as critically endangered in the risk list for Brazilian flora.

Is There a Relationship between Zinc and the Peculiar Comorbidities of Down Syndrome?

ERIC Educational Resources Information Center

Romano, Corrado; Pettinato, Rosa; Ragusa, Letizia; Barone, Concetta; Alberti, Antonino; Failla, Pinella

2002-01-01

A comparison was made between a range of clinical and biochemical variables and zinc levels in 120 individuals with Down syndrome. No significant differences were found between the normal-zinc and low-zinc groups, except for IgG4 which was, unexpectedly, significantly decreased in the group with normal zinc levels. (Contains references.)…

The Effect of Locus of Control, Self-Efficacy, and Gender-Role Identity on Academic Performance Outcomes of Female College Students

ERIC Educational Resources Information Center

Sierra, Jade Simone

2013-01-01

This quantitative study investigated the predictive worthiness of the predictor variable indices--locus of control, self-efficacy, and gender identity--to ascertain if elevated levels of the predictors influence academic performance outcomes (individually as well as interactionally). The study theorized that students with increased levels of locus…

Multilevel Analyses of School and Children's Characteristics Associated with Physical Activity

ERIC Educational Resources Information Center

Gomes, Thayse Natacha; dos Santos, Fernanda K.; Zhu, Weimo; Eisenmann, Joey; Maia, José A. R.

2014-01-01

Background: Children spend most of their awake time at school, and it is important to identify individual and school-level correlates of their physical activity (PA) levels. This study aimed to identify the between-school variability in Portuguese children PA and to investigate student and school PA correlates using multilevel modeling. Methods:…

The Relationship between Economic Growth and School Enrollment Rates: Time Series Evidence from Turkey

ERIC Educational Resources Information Center

Gumus, Sedat; Kayhan, Selim

2012-01-01

It has long been argued that there is a close relationship between education and economic development at both individual and societal levels. Economists have found that the level of educational infrastructure is an important indicator of economic development. Similarly, economic variables have been found to be strongly related to school enrollment…

Consistent levels of A-to-I RNA editing across individuals in coding sequences and non-conserved Alu repeats

PubMed Central

2010-01-01

Background Adenosine to inosine (A-to-I) RNA-editing is an essential post-transcriptional mechanism that occurs in numerous sites in the human transcriptome, mainly within Alu repeats. It has been shown to have consistent levels of editing across individuals in a few targets in the human brain and altered in several human pathologies. However, the variability across human individuals of editing levels in other tissues has not been studied so far. Results Here, we analyzed 32 skin samples, looking at A-to-I editing level in three genes within coding sequences and in the Alu repeats of six different genes. We observed highly consistent editing levels across different individuals as well as across tissues, not only in coding targets but, surprisingly, also in the non evolutionary conserved Alu repeats. Conclusions Our findings suggest that A-to-I RNA-editing of Alu elements is a tightly regulated process and, as such, might have been recruited in the course of primate evolution for post-transcriptional regulatory mechanisms. PMID:21029430

Social capital and self-rated health among middle-aged and older adults in China: a multilevel analysis.

PubMed

Shen, Yuying; Yeatts, Dale E; Cai, Tianji; Yang, Philip Q; Cready, Cynthia M

2014-07-01

This study examined the association between social capital, at both the individual and the community level, and self-rated health among older adults in China. Using data from the 2008 Pilot Survey of China Health and Retirement Longitudinal Study, a series of multilevel logistic models were estimated in SAS 9.2. The association between social capital and self-rated health was examined among 996 adults aged 45 or older from two provinces in China, while controlling for demographic characteristics and socioeconomic variables. Our results suggest the significant association between certain aspects of social capital, at both the individual and the community level, and self-rated health. The individual-level social capital in the form of perceived help in the future and the social capital of community in the form of the availability of amenities and associations within the community were significantly related to self-rated health. A significant cross-level interaction effect between individual- and community-level social capital was also observed. © The Author(s) 2013.

Association of polymorphisms in genes involved in lipoprotein metabolism with plasma concentrations of remnant lipoproteins and HDL subpopulations before and after hormone therapy in postmenopausal women

USDA-ARS?s Scientific Manuscript database

A high degree of inter-individual variability in plasma lipid level response to hormone therapy (HT) has been reported. Variations in the estrogen receptor alpha gene (ESR1) and in genes involved in lipid metabolism may explain some of the variability in response to HT. We studied the effect of sin...

Level of recall, retrieval speed, and variability on the Cued-Recall Retrieval Speed Task (CRRST) in individuals with amnestic mild cognitive impairment.

PubMed

Ramratan, Wendy S; Rabin, Laura A; Wang, Cuiling; Zimmerman, Molly E; Katz, Mindy J; Lipton, Richard B; Buschke, Herman

2012-03-01

Individuals with amnestic mild cognitive impairment (aMCI) show deficits on traditional episodic memory tasks and reductions in speed of performance on reaction time tasks. We present results on a novel task, the Cued-Recall Retrieval Speed Task (CRRST), designed to simultaneously measure level and speed of retrieval. A total of 390 older adults (mean age, 80.2 years), learned 16 words based on corresponding categorical cues. In the retrieval phase, we measured accuracy (% correct) and retrieval speed/reaction time (RT; time from cue presentation to voice onset of a correct response) across 6 trials. Compared to healthy elderly adults (HEA, n = 303), those with aMCI (n = 87) exhibited poorer performance in retrieval speed (difference = -0.13; p < .0001) and accuracy on the first trial (difference = -0.19; p < .0001), and their rate of improvement in retrieval speed was slower over subsequent trials. Those with aMCI also had greater within-person variability in processing speed (variance ratio = 1.22; p = .0098) and greater between-person variability in accuracy (variance ratio = 2.08; p = .0001) relative to HEA. Results are discussed in relation to the possibility that computer-based measures of cued-learning and processing speed variability may facilitate early detection of dementia in at-risk older adults.

Individual- and neighborhood-level contextual factors are associated with Mycobacterium tuberculosis transmission: genotypic clustering of cases in Michigan, 2004-2012.

PubMed

Noppert, Grace A; Yang, Zhenhua; Clarke, Philippa; Ye, Wen; Davidson, Peter; Wilson, Mark L

2017-06-01

Using genotyping data of Mycobacterium tuberculosis isolates from new cases reported to the tuberculosis (TB) surveillance program, we evaluated risk factors for recent TB transmission at both the individual- and neighborhood- levels among U.S.-born and foreign-born populations. TB cases (N = 1236) reported in Michigan during 2004 to 2012 were analyzed using multivariable Poisson regression models to examine risk factors for recent transmission cross-sectionally for U.S.-born and foreign-born populations separately. Recent transmission was defined based on spoligotype and 12-locus-mycobacterial interspersed repetitive unit-variable number tandem repeat typing matches of bacteria from cases that were diagnosed within 1 year of each other. Four classes of predictor variables were examined: demographic factors, known TB risk factors, clinical characteristics, and neighborhood-level factors. Overall, 22% of the foreign-born cases resulted from recent transmission. Among the foreign-born, race and being a contact of an infectious TB case were significant predictors of recent transmission. More than half (52%) of U.S.-born cases resulted from recent transmission. Among the U.S.-born, recent transmission was predicted by both individual- and neighborhood-level sociodemographic characteristics. Interventions aimed at reducing TB incidence among foreign-born should focus on reducing reactivation of latent infection. However, reducing TB incidence among the U.S.-born will require decreasing transmission among socially disadvantaged groups at the individual- and neighborhood- levels. This report fills an important knowledge gap regarding the contemporary social context of TB in the United States, thereby providing a foundation for future studies of public health policies that can lead to the development of more targeted, effective TB control. Copyright © 2017 Elsevier Inc. All rights reserved.

ICD-10 mental and behavioural disorders due to use of crack and powder cocaine as treated at a public psychiatric emergency service: an analysis of visit predictors.

PubMed

da Cruz, Thalita Alves; da Cunha, Gustavo Nunes; de Moraes, Vinicius Papa Milani; Massarini, Renata; Yoshida, Camila Mie Kawata; Tenguam, Patrícia Tomiatto; Garcia, Marcelo Valeiro; Varoto, Daniela Arruda; de Oliveira, Murilo Barutti; de Andrade, Arthur Guerra; de Azevedo-Marques Périco, Cíntia; do Nascimento, Vania Barbosa; Castaldelli-Maia, João Mauricio

2014-08-01

The present study investigated the predictors of an increased number of visits from individuals with some of the diagnoses noted in chapter F14 of ICD-10, from calls to the emergency psychiatric unit of a general hospital in São Paulo state, Brazil, in the period 2011-2012. Poisson regression models were carried out for the outcome variable, accounting for number of subsequent visits to the psychiatric emergency unit. For the analysis of this outcome we took into account the exposure time of each individual in the study. Our findings point to a population at risk for frequent psychiatric emergency service visits: individuals over 25 years. This population should be targeted for interventions on entry into public healthcare due to increased psychiatric morbidity and greater clinical morbidity already confirmed by previous studies. We discussed the need of these individuals for special attention during the clinical or psychiatric emergency consultation which, unfortunately, may be the access point for the public health system. None of the other variables were related to the outcome of interest, such as those related to the level of individual entry into the care network before and after treatment, and other variables related to medical acts during the visit.

Socioeconomic status and exposure to outdoor NO2 and benzene in the Asturias INMA birth cohort, Spain.

PubMed

Fernández-Somoano, Ana; Tardon, Adonina

2014-01-01

It is commonly assumed that low socioeconomic levels are associated with greater exposure to pollution, but this is not necessarily valid. Our goal was to examine how individual socioeconomic characteristics are associated with exposure levels in a Spanish region included in the INfancia y Medio Ambiente (INMA) cohort. The study population comprised 430 pregnant women from the Asturias INMA cohort. Air pollution exposure was estimated using land-use regression techniques. Information about the participants' lifestyle and socioeconomic variables was collected through questionnaires. In multivariate analysis, the levels of NO2 and benzene assigned to each woman were considered as dependent variables. Other variables included in the models were residential zone, age, education, parity, smoking, season, working status during pregnancy and social class. The average NO2 level was 23.60 (SD=6.50) μg/m(3). For benzene, the mean value was 2.31 (SD=1.32) μg/m(3). We found no association of any pollutant with education. We observed an association between social class and benzene levels. Social classes I and II had the highest levels. The analysed socioeconomic and lifestyle variables accounted for little variability in air pollution in the models; this variability was explained mainly by residential zone (adjusted R(2): 0.27 for NO2; 0.09 for benzene). Education and social class were not clearly associated with pollution. Administrations should monitor the environment of residential areas regardless of the socioeconomic level, and they should increase the distances between housing and polluting sources to prevent settlements at distances that are harmful to health.

Geographic information system and multilevel analysis: gingival status among 12-year-old schoolchildren in São Paulo, Brazil.

PubMed

Pereira, Stela Márcia; Pardi, Vanessa; Cortellazzi, Karine L; Ambrosano, Glaucia Maria Bovi; Vettorazzi, Carlos Alberto; Ferraz, Sílvio F B; Meneghim, Marcelo de Castro; Pereira, Antonio Carlos

2014-02-01

To evaluate gingival and calculus status among schoolchildren 12 years of age using a geographic information system and multilevel analysis. A total of 1 002 schoolchildren were selected from 18 municipal districts by means of cluster sampling, from among 25 public and private schools in Piracicaba, São Paulo, Brazil, in 2005. Examinations were carried out by a single calibrated examiner utilizing the criteria of the World Health Organization, as well as the Community Periodontal Index. Social, economic, and behavioral variables were recorded with the use of a questionnaire and were used in the individual analysis (first level). The variables "percentage of heads of families without income" and "percentage of illiterate heads of families" were used in the contextual analysis (second level). A geographic information system was constructed for mapping the distribution of gingival bleeding. The variables were visually distinguished in the maps and demonstrated a tendency toward better gingival health in the central areas of the city, which are recognized as more privileged. On the contextual level, only the "percentage of illiterate heads of families" was significantly associated to gingival bleeding. The study confirms better oral health status among schoolchildren from privileged families, but does not confirm the data regarding "income." The individuals from areas in which the heads of family did not have income were not associated to a higher prevalence of gingival problems. This suggests that these individuals are reasonably protected from the impact of social privation due to the actions of public health care services in the municipality.

A Novel Group-Fused Sparse Partial Correlation Method for Simultaneous Estimation of Functional Networks in Group Comparison Studies.

PubMed

Liang, Xiaoyun; Vaughan, David N; Connelly, Alan; Calamante, Fernando

2018-05-01

The conventional way to estimate functional networks is primarily based on Pearson correlation along with classic Fisher Z test. In general, networks are usually calculated at the individual-level and subsequently aggregated to obtain group-level networks. However, such estimated networks are inevitably affected by the inherent large inter-subject variability. A joint graphical model with Stability Selection (JGMSS) method was recently shown to effectively reduce inter-subject variability, mainly caused by confounding variations, by simultaneously estimating individual-level networks from a group. However, its benefits might be compromised when two groups are being compared, given that JGMSS is blinded to other groups when it is applied to estimate networks from a given group. We propose a novel method for robustly estimating networks from two groups by using group-fused multiple graphical-lasso combined with stability selection, named GMGLASS. Specifically, by simultaneously estimating similar within-group networks and between-group difference, it is possible to address inter-subject variability of estimated individual networks inherently related with existing methods such as Fisher Z test, and issues related to JGMSS ignoring between-group information in group comparisons. To evaluate the performance of GMGLASS in terms of a few key network metrics, as well as to compare with JGMSS and Fisher Z test, they are applied to both simulated and in vivo data. As a method aiming for group comparison studies, our study involves two groups for each case, i.e., normal control and patient groups; for in vivo data, we focus on a group of patients with right mesial temporal lobe epilepsy.

Visit-to-visit cholesterol variability correlates with coronary atheroma progression and clinical outcomes.

PubMed

Clark, Donald; Nicholls, Stephen J; St John, Julie; Elshazly, Mohamed B; Kapadia, Samir R; Tuzcu, E Murat; Nissen, Steven E; Puri, Rishi

2018-04-21

Utilizing serial intravascular ultrasonography (IVUS), we aimed to exam the association of intra-individual lipid variability, coronary atheroma progression, and clinical outcomes. We performed a post hoc patient-level analysis of nine clinical trials involving 4976 patients with coronary artery disease who underwent serial coronary IVUS in the setting of a range of medical therapies. We assessed the associations between progression in percent atheroma volume (ΔPAV), clinical outcomes, and visit-to-visit lipid variability including low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), non-HDL-C, total cholesterol (TC)/HDL-C, and apolipoprotein B (ApoB). Variability of lipid parameters was measured using intra-individual standard deviation over 3, 6, 12, 18, and 24 months. Atherogenic lipoprotein variability significantly associated with ΔPAV [odds ratio (95% confidence interval; P-value), LDL-C: 1.09 (1.02, 1.17, P = 0.01); non-HDL-C: 1.10 (1.02, 1.18, P = 0.01); TC/HDL-C: 1.14 (1.06, 1.24, P = 0.001); ApoB: 1.13 (1.03, 1.24, P = 0.01)]. Survival curves revealed significant stepwise relationships between cumulative major adverse cardiovascular events and increasing quartiles of atherogenic lipoprotein variability at 24-months follow-up (log-rank P < 0.01 for all lipoproteins except HDL-C). Stronger associations were noted between achieved lipoprotein levels and ΔPAV [LDL-C: 1.27 (1.17, 1.39; P < 0.001); non-HDL-C: 1.32 (1.21, 1.45; P < 0.001); TC/HDL-C: 1.31 (1.19, 1.45; P < 0.001); ApoB: 1.20 (1.07, 1.35; P = 0.003)]. Greater visit-to-visit variability in atherogenic lipoprotein levels significantly associates with coronary atheroma progression and clinical outcomes, although the association between achieved atherogenic lipoproteins and atheroma progression appears stronger. These data highlight the importance of achieving low and consistent atherogenic lipoprotein levels to promote plaque regression and improve clinical outcomes.

To migrate, stay put, or wander? Varied movement strategies in bald eagles (Haliaeetus leucocephalus).

PubMed

Wheat, Rachel E; Lewis, Stephen B; Wang, Yiwei; Levi, Taal; Wilmers, Christopher C

2017-01-01

Quantifying individual variability in movement behavior is critical to understanding population-level patterns in animals. Here, we explore intraspecific variation in movement strategies of bald eagles ( Haliaeetus leucocephalus ) in the north Pacific, where there is high spatiotemporal resource variability. We tracked 28 bald eagles (five immature, 23 adult) using GPS transmitters between May 2010 and January 2016. We found evidence of four movement strategies among bald eagles in southeastern Alaska and western Canada: breeding individuals that were largely sedentary and remained near nest sites year-round, non-breeding migratory individuals that made regular seasonal travel between northern summer and southern winter ranges, non-breeding localized individuals that displayed fidelity to foraging sites, and non-breeding nomadic individuals with irregular movement. On average, males traveled farther per day than females. Most nomadic individuals were immature, and all residential individuals (i.e. breeders and localized birds) were adults. Alternative movement strategies among north Pacific eagles are likely associated with the age and sex class, as well as breeding status, of an individual. Intraspecific variation in movement strategies within the population results in different space use patterns among contingents, which has important implications for conservation and management.

Individual Movement Variability Magnitudes Are Explained by Cortical Neural Variability.

PubMed

Haar, Shlomi; Donchin, Opher; Dinstein, Ilan

2017-09-13

Humans exhibit considerable motor variability even across trivial reaching movements. This variability can be separated into specific kinematic components such as extent and direction that are thought to be governed by distinct neural processes. Here, we report that individual subjects (males and females) exhibit different magnitudes of kinematic variability, which are consistent (within individual) across movements to different targets and regardless of which arm (right or left) was used to perform the movements. Simultaneous fMRI recordings revealed that the same subjects also exhibited different magnitudes of fMRI variability across movements in a variety of motor system areas. These fMRI variability magnitudes were also consistent across movements to different targets when performed with either arm. Cortical fMRI variability in the posterior-parietal cortex of individual subjects explained their movement-extent variability. This relationship was apparent only in posterior-parietal cortex and not in other motor system areas, thereby suggesting that individuals with more variable movement preparation exhibit larger kinematic variability. We therefore propose that neural and kinematic variability are reliable and interrelated individual characteristics that may predispose individual subjects to exhibit distinct motor capabilities. SIGNIFICANCE STATEMENT Neural activity and movement kinematics are remarkably variable. Although intertrial variability is rarely studied, here, we demonstrate that individual human subjects exhibit distinct magnitudes of neural and kinematic variability that are reproducible across movements to different targets and when performing these movements with either arm. Furthermore, when examining the relationship between cortical variability and movement variability, we find that cortical fMRI variability in parietal cortex of individual subjects explained their movement extent variability. This enabled us to explain why some subjects performed more variable movements than others based on their cortical variability magnitudes. Copyright © 2017 the authors 0270-6474/17/379076-10$15.00/0.

Development and validation of classifiers and variable subsets for predicting nursing home admission.

PubMed

Nuutinen, Mikko; Leskelä, Riikka-Leena; Suojalehto, Ella; Tirronen, Anniina; Komssi, Vesa

2017-04-13

In previous years a substantial number of studies have identified statistically important predictors of nursing home admission (NHA). However, as far as we know, the analyses have been done at the population-level. No prior research has analysed the prediction accuracy of a NHA model for individuals. This study is an analysis of 3056 longer-term home care customers in the city of Tampere, Finland. Data were collected from the records of social and health service usage and RAI-HC (Resident Assessment Instrument - Home Care) assessment system during January 2011 and September 2015. The aim was to find out the most efficient variable subsets to predict NHA for individuals and validate the accuracy. The variable subsets of predicting NHA were searched by sequential forward selection (SFS) method, a variable ranking metric and the classifiers of logistic regression (LR), support vector machine (SVM) and Gaussian naive Bayes (GNB). The validation of the results was guaranteed using randomly balanced data sets and cross-validation. The primary performance metrics for the classifiers were the prediction accuracy and AUC (average area under the curve). The LR and GNB classifiers achieved 78% accuracy for predicting NHA. The most important variables were RAI MAPLE (Method for Assigning Priority Levels), functional impairment (RAI IADL, Activities of Daily Living), cognitive impairment (RAI CPS, Cognitive Performance Scale), memory disorders (diagnoses G30-G32 and F00-F03) and the use of community-based health-service and prior hospital use (emergency visits and periods of care). The accuracy of the classifier for individuals was high enough to convince the officials of the city of Tampere to integrate the predictive model based on the findings of this study as a part of home care information system. Further work need to be done to evaluate variables that are modifiable and responsive to interventions.

Variability of fibrinogen measurements in post-myocardial infarction patients. Results from the AIRGENE study center Augsburg.

PubMed

Baumert, Jens; Karakas, Mahir; Greven, Sonja; Rückerl, Regina; Peters, Annette; Koenig, Wolfgang

2012-05-01

Elevated fibrinogen levels are strongly and consistently associated with incident coronary heart disease (CHD). A possible causal contribution of fibrinogen in the pathway leading to atherothrombotic cardiovascular disease complications has been suggested. However, for implementation in clinical practice, data on validity and reliability, which are still scarce, are needed that are still scarce, especially in subjects with a history of CHD. For the present study, levels of plasma fibrinogen were measured in 200 post-myocardial infarction (post-MI) patients aged 39-76 years, with approximately six blood samples collected at monthly intervals between May 2003 and March 2004, giving a total of 1,144 samples. Inter-individual variability (between-subject variance component, VCb and coefficient of variation, CVb), intra-individual and analytical variability (VCw+a and CVw+a), intraclass correlation coefficient (ICC) and the number of measurements required for an ICC of 0.75 were estimated to assess the reliability of serial fibrinogen measurements. Mean fibrinogen concentration of all subjects over all samples was 3.34 g/l (standard deviation 0.67). Between-subject variation for fibrinogen was VCb = 0.34 (CVb'=17.5%) whereas within-subject and analytical variation was estimated as VCw+a = 0.14 (CVw+a=11.0%). The variation was mainly explained by between-subject variability, shown by the proportion of total variance of 71.3%. Two different measurements were required to reach sufficient reliability, if subjects with extreme values were not excluded. The present study indicates a fairly good reproducibility of serial individual fibrinogen measurements in post-MI subjects.

Labour participation of people living with HIV/AIDS in Spain.

PubMed

Oliva, Juan

2010-04-01

This study explores the relationship between the employment status of human immunodeficiency virus (HIV)-positive individuals and socioeconomic and health characteristics in Spain. Data were obtained from four waves of the HIV/AIDS Hospital Survey from the period 2001 to 2004. The sample was composed of 3376 individuals between 16 and 64 years. Assessment of employment participation was performed using a probit model on a wide range of socioeconomic and lifestyle-related variables. The main variables explaining the probability of participation in the labour market were age, gender, education level, CD4 cell count, health status, time since HIV diagnosis, psychological impact of contracting the disease or its progression, the most likely means of transmission and intravenous drug use (IDU). The significance of each of these variables differs for men and women as well as for injecting drug users (IDUs) and non-IDUs. The employment status of HIV-positive individuals is directly related to their health status and other personal characteristics. Policies to improve the well-being of HIV-positive individuals should not be limited to any one sector as their needs require strategies with a multidisciplinary approach. Copyright (c) 2009 John Wiley & Sons, Ltd.

Access to Primary Care in US Counties Is Associated with Lower Obesity Rates.

PubMed

Gaglioti, Anne H; Petterson, Stephen; Bazemore, Andrew; Phillips, Robert

2016-01-01

Obesity causes substantial morbidity and mortality in the United States. Evidence shows that primary care physician (PCP) supply correlates positively with improved health, but its association with obesity in the United States as not been adequately characterized. Our purpose was to characterize the association between PCP supply in US counties and adult obesity. We performed a multivariate logistic regression analysis to examine the relationship between county-level PCP supply and individual obesity status. We controlled for individual variables, including sex, race, marital status, income, and insurance status, and county-level variables, including rurality and poverty. Higher county-level PCP supply was associated with lower adult obesity after controlling for common confounders. Individuals living in counties with the most robust PCP supply were about 20% less likely to be obese (P ≤ .01) than those living in counties with the lowest PCP supply. While the observed association between the supply of PCPs and lower rates of obesity may not be causal, the association warrants further investigation. This may have important implications for restructuring the physician workforce in the context of the current PCP shortage and implementation of the Affordable Care Act and the patient-centered medical home. © Copyright 2016 by the American Board of Family Medicine.

Cardiovascular risk factors in the normoglycaemic Asian-Indian population--influence of urbanisation.

PubMed

Snehalatha, C; Ramachandran, A

2009-04-01

The aim of this study was to investigate the prevalence of cardiovascular risk factors in normoglycaemic Asian-Indians and its association with urbanisation and plasma glucose. Data on 5,517 normoglycaemic individuals aged >/=20 years (1,521, 1,851 and 2,145 inhabitants of a city, a town and villages, respectively), from a 2006 diabetes survey, were used. The presence of single and multiple abnormalities, including obesity, abdominal obesity, hypertension and dyslipidaemia, was analysed. Risk associations for hypertension and dyslipidaemia were analysed using multivariate analysis after adjusting for confounding variables. Both the prevalence and clustering of cardiovascular risk variables were higher in urban areas than in villages, and were higher in the city than in the town. Nearly half (47%) of the normoglycaemic individuals from villages had at least one risk factor. Age, male sex, BMI, waist circumference, lack of physical activity and living in an urban environment were associated with hypertension and dyslipidaemia; postprandial glucose level showed no association with hypertension or dyslipidaemia after adjusting for these risk factors. Fasting plasma glucose level showed an independent association with dyslipidaemia. There is a high prevalence of cardiovascular risk factors even among normoglycaemic individuals, and this is highest in urban areas. Fasting plasma glucose level showed an association with dyslipidaemia but not hypertension.

Individual-level, network-level and city-level factors associated with HIV prevalence among people who inject drugs in eight Russian cities: a cross-sectional study

PubMed Central

Eritsyan, Ksenia; Heimer, Robert; Barbour, Russell; Odinokova, Veronika; White, Edward; Rusakova, Maia M; Smolskaya, Tatiana T; Levina, Olga S

2013-01-01

Objectives To ascertain HIV prevalence among people who inject drug (injection drug users (IDUs)) in the Russian Federation and identify explanations for the disparity in different cities. Design Cross-sectional survey with serological testing for HIV and hepatitis C virus prevalent infections. Setting 8 Russian cities—Irkutsk, Omsk, Chelyabinsk, Yekaterinburg, Naberezhnye Chelny, Voronezh, Orel and St Petersburg. Participants In 2007–2009 active IDUs were recruited by respondent-driven sampling with a target sample size of 300 or more in each city. Main outcome measures Participants were administered a questionnaire covering sociodemographics, injection risk and protective behaviours, sexual behaviours, HIV knowledge, experiences with drug treatment and harm reduction programmes and social networks. Participants were tested for HIV and hepatitis C by enzyme immunoassay. Data were analysed to identify individual-level, network-level and city-level characteristics significantly associated with HIV prevalence. Factors significant at p≤0.1 were entered into a hierarchical regression model to control for multicollinearity. Results A total of 2596 active IDUs were recruited, interviewed and tested for HIV and hepatitis C virus infection. HIV prevalence ranged from 3% (in Voronezh) to 64% (in Yekaterinburg). Although individual-level and network-level variables explain some of the difference in prevalence across the eight cities, the over-riding variable that seems to account for most of the variance is the emergence of commercial, as opposed to homemade, heroin as the predominant form of opioid injected. Conclusions The expansion of commercial heroin markets to many Russian cities may have served as a trigger for an expanding HIV epidemic among IDUs in that country. PMID:23794559

Longitudinal multiple imputation approaches for body mass index or other variables with very low individual-level variability: the mibmi command in Stata.

PubMed

Kontopantelis, Evangelos; Parisi, Rosa; Springate, David A; Reeves, David

2017-01-13

In modern health care systems, the computerization of all aspects of clinical care has led to the development of large data repositories. For example, in the UK, large primary care databases hold millions of electronic medical records, with detailed information on diagnoses, treatments, outcomes and consultations. Careful analyses of these observational datasets of routinely collected data can complement evidence from clinical trials or even answer research questions that cannot been addressed in an experimental setting. However, 'missingness' is a common problem for routinely collected data, especially for biological parameters over time. Absence of complete data for the whole of a individual's study period is a potential bias risk and standard complete-case approaches may lead to biased estimates. However, the structure of the data values makes standard cross-sectional multiple-imputation approaches unsuitable. In this paper we propose and evaluate mibmi, a new command for cleaning and imputing longitudinal body mass index data. The regression-based data cleaning aspects of the algorithm can be useful when researchers analyze messy longitudinal data. Although the multiple imputation algorithm is computationally expensive, it performed similarly or even better to existing alternatives, when interpolating observations. The mibmi algorithm can be a useful tool for analyzing longitudinal body mass index data, or other longitudinal data with very low individual-level variability.

Exploring factors related to physical activity in cervical dystonia.

PubMed

Zetterberg, Lena; Urell, Charlotte; Anens, Elisabeth

2015-12-01

People with disabilities have reported worse health status than people without disabilities and receiving fewer preventive health services such as counseling around exercise habits. This is noteworthy considering the negative consequences associated with physical inactivity. No research has been conducted on physical activity in cervical dystonia (CD), despite its possible major impact on self-perceived health and disability. Considering the favorable consequences associated with physical activity it is important to know how to promote physical activity behavior in CD. Knowledge of variables important for such behavior in CD is therefore crucial. The aim of this study was to explore factors related to physical activity in individuals with cervical dystonia. Subjects included in this cross-sectional study were individuals diagnosed with CD and enrolled at neurology clinics (n = 369). Data was collected using one surface mailed self-reported questionnaire. Physical activity was the primary outcome variable, measured with the Physical Activity Disability Survey. Secondary outcome variables were: impact of dystonia measured with the Cervical Dystonia Impact Scale; fatigue measured with the Fatigue Severity Scale; confidence when carrying out physical activity measured with the Exercise Self-Efficacy Scale; confidence in performing daily activities without falling measured with the Falls Efficacy Scale; enjoyment of activity measured with Enjoyment of Physical Activity Scale, and social influences on physical activity measured with Social Influences on Physical Activity in addition to demographic characteristics such as age, education level and employment status. The questionnaire was completed by 173 individuals (47% response rate). The multivariate association between related variables and physical activity showed that employment, self-efficacy for physical activity, education level and consequences for daily activities explained 51% of the variance in physical activity (Adj R 0.51, F (5, 162) = 35.611, p = 0.000). Employment and self-efficacy for physical activity contributed most strongly to the association with physical activity. Considering the favorable consequences associated with physical activity it could be important to support the individuals with CD to remain in work and self-efficacy to physical activity as employment and self-efficacy had significant influence on physical activity level. Future research is needed to evaluate causal effects of physical activity on consequences related to CD.

Long term unemployment, income, poverty, and social public expenditure, and their relationship with self-perceived health in Spain (2007-2011).

PubMed

López Del Amo González, M Puerto; Benítez, Vivian; Martín-Martín, José J

2018-01-15

There is scant research that simultaneously analyzes the joint effects of long-term unemployment, poverty and public expenditure policies on poorer self-perceived health during the financial crisis. The aim of the study is to analyze the joint relationship between long-term unemployment, social deprivation, and regional social public expenditure on one side, and self-perceived health in Spain (2007-2011) on the other. Longitudinal data were extracted from the Survey on Living Conditions, 2007-2010 and 2008-2011 (9105 individuals and 36,420 observations), which were then used to estimate several random group effects in the constant multilevel logistic longitudinal models (level 1: year; level 2: individual; level 3: region). The dependent variable was self-perceived health. Individual independent interest variables were long and very long term unemployment, available income, severe material deprivation and regional variables were per capita expenditure on essential public services and per capita health care expenditure. All of the estimated models show a robust association between bad perceived health and the variables of interest. When compared to employed individuals, long term unemployment increases the odds of reporting bad health by 22% to 67%; very long-term unemployment (24 to 48 months) increases the odds by 54% to 132%. Family income reduces the odds of reporting bad health by 16% to 28% for each additional percentage point in income. Being a member of a household with severe material deprivation increases the odds of perceiving one's health as bad by between 70% and 140%. Regionally, per capita expenditure on essential public services increases the odds of reporting good health, although the effect of this association was limited. Long and very long term unemployment, available income and poverty were associated to self-perceived bad health in Spain during the financial crisis. Regional expenditure on fundamental public services is also associated to poor self-perceived health, although in a more limited fashion. Results suggest the positive role in health of active employment and redistributing income policies.

Predicting Health Resilience in Pediatric Type 1 Diabetes: A Test of the Resilience Model Framework.

PubMed

Rohan, Jennifer M; Huang, Bin; Pendley, Jennifer Shroff; Delamater, Alan; Dolan, Lawrence; Reeves, Grafton; Drotar, Dennis

2015-10-01

This research examined whether individual and family-level factors during the transition from late childhood to early adolescence protected individuals from an increased risk of poor glycemic control across time, which is a predictor of future diabetes-related complications (i.e., health resilience). This longitudinal, multisite study included 239 patients with type 1 diabetes and their caregivers. Glycemic control was based on hemoglobin A1c. Individual and family-level factors included: demographic variables, youth behavioral regulation, adherence (frequency of blood glucose monitoring), diabetes self-management, level of parental support for diabetes autonomy, level of youth mastery and responsibility for diabetes management, and diabetes-related family conflict. Longitudinal mixed-effects logistic regression indicated that testing blood glucose more frequently, better self-management, and less diabetes-related family conflict were indicators of health resilience. Multiple individual and family-level factors predicted risk for future health complications. Future research should develop interventions targeting specific individual and family-level factors to sustain glycemic control within recommended targets, which reduces the risk of developing future health complications during the transition to adolescence and adulthood. © The Author 2015. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The relationship of area-level sociodemographic characteristics, household composition and individual-level socioeconomic status on walking behavior among adults.

PubMed

Hearst, Mary O; Sirard, John R; Forsyth, Ann; Parker, Emily D; Klein, Elizabeth G; Green, Christine G; Lytle, Leslie A

2013-04-01

Understanding the contextual factors associated with why adults walk is important for those interested in increasing walking as a mode of transportation and leisure. This paper investigates the relationships between neighborhood-level sociodemographic context, individual level sociodemographic characteristics and walking for leisure and transport. Data from two community-based studies of adults (n=550) were used to determine the association between the area-sociodemographic environment (ASDE), calculated from U.S. Census variables, and individual-level SES as potential correlates of walking behavior. Descriptive statistics, mean comparisons and Pearson's correlations coefficients were used to assess bivariate relationships. Generalized estimating equations were used to model the relationship between ASDE, as quartiles, and walking behavior. Adjusted models suggest adults engage in more minutes of walking for transportation and less walking for leisure in the most disadvantaged compared to the least disadvantaged neighborhoods but adding individual level demographics and SES eliminated the significant results. However, when models were stratified for free or reduced cost lunch, of those with children who qualified for free or reduced lunch, those who lived in the wealthiest neighborhoods engaged in 10.7 minutes less of total walking per day compared to those living in the most challenged neighborhoods (p<0.001). Strategies to increase walking for transportation or leisure need to take account of individual level socioeconomic factors in addition to area-level measures.

Alcohol-related negative consequences among drinkers around the world.

PubMed

Graham, Kathryn; Bernards, Sharon; Knibbe, Ronald; Kairouz, Sylvia; Kuntsche, Sandra; Wilsnack, Sharon C; Greenfield, Thomas K; Dietze, Paul; Obot, Isidore; Gmel, Gerhard

2011-08-01

This paper examines (i) gender and country differences in negative consequences related to drinking; (ii) relative rates of different consequences; and (iii) country-level predictors of consequences. Multi-level analyses used survey data from the Gender, Alcohol, and Culture: An International Study (GENACIS) collaboration. Measures included 17 negative consequences grouped into (i) high endorsement acute, (ii) personal and (iii) social. Country-level measures included average frequency and quantity of drinking, percentage who were current drinkers, gross domestic product (GDP) and Human Development Index (HDI). Overall, the three groupings of consequences were reported by 44%, 12% and 7% of men and by 31%, 6% and 3% of women, respectively. More men than women endorsed all consequences, but gender differences were greatest for consequences associated with chronic drinking and social consequences related to male roles. The highest prevalence of consequences was in Uganda and lowest in Uruguay. Personal and social consequences were more likely in countries with higher usual quantity, fewer current drinkers and lower scores on GDP and HDI. However, significant interactions with individual-level quantity indicated a stronger relationship between consequences and usual quantity among drinkers in countries with lower quantity, more current drinkers and higher scores on GDP and HDI. Both gender and country need to be taken into consideration when assessing adverse drinking consequences. Individual measures of alcohol consumption and country-level variables are associated with experiencing such consequences. Additionally, country-level variables affect the strength of the relationship between usual quantity consumed by individuals and adverse consequences. © 2011 The Authors, Addiction © 2011 Society for the Study of Addiction.

Caregiver's education level, not income, as determining factor of dietary intake and nutritional status of individuals cared for at home.

PubMed

Correa, B; Leandro Merhi, V A; Pagotto Fogaca, K; Marques de Oliveira, M R

2009-08-01

Home care should intervene in the nutritional status of the elderly. To analyze the nutritional status of the elderly assisted by a Home Care Program (PAD) and associate it with income and education level of the caregiver. Thirty-four individuals of both genders who received home care from PAD. The MNA (Mini Nutritional Assessment) was used along with arm circumference. Dietary intake assessment was done with three 24-hour recalls in non-consecutive days. We collected data on income, education level of the caregiver and user in years of formal education and autonomy of user. The differences between the proportions of the nominal variables were tested by the chi-square test. The continuous variables were tested for normality and if normal, the Student's t-test or ANOVA was applied. The adopted significance level was P < 0.05. The studied sample represented individuals older than 65 years, assisted by PAD and 100% dependent on the caregiver. MNA revealed that 38.2% of the users were malnourished and 61.8% were at risk for malnourishment. Energy, fiber, vitamin E, calcium and zinc intakes were inadequate. Education level of the caregivers was a determining factor (P=0.01) for the nutritional status of the elderly while no association was found with respect to income. These findings allows us to conclude that the nutritional status of this population is worrisome and that it may be associated with low quality of life influenced by the education level of the caregiver, but also by age, economic conditions and limited autonomy of this population.

Perceptions of social capital and the built environment and mental health.

PubMed

Araya, Ricardo; Dunstan, Frank; Playle, Rebecca; Thomas, Hollie; Palmer, Stephen; Lewis, Glyn

2006-06-01

There has been much speculation about a possible association between the social and built environment and health, but the empirical evidence is still elusive. The social and built environments are best seen as contextual concepts but they are usually estimated as an aggregation of individual compositional measures, such as perceptions on trust or the desirability to live in an area. If these aggregated compositional measures were valid measures, one would expect that they would evince correlations at higher levels of data collection (e.g., neighbourhood). The aims of this paper are: (1) to investigate the factor structure of a self-administered questionnaire measuring individual perceptions of trust, social participation, social cohesion, social control, and the built environment; (2) to investigate variation in these factors at higher than the individual level (households and postcodes) in order to assess if these constructs reflect some contextual effect; and (3) to study the association between mental health, as measured by the General Health Questionnaire-12 (GHQ-12), and these derived factors. A cross-sectional household survey was undertaken during May-August 2001 in a district of South Wales with a population of 140,000. We found that factor analysis grouped our questions in factors similar to the theoretical ones we had previously envisaged. We also found that approximately one-third of the variance for neighbourhood quality and 10% for social control was explained at postcode (neighbourhood) level after adjusting for individual variables, thus suggesting that some of our compositional measures capture contextual characteristics of the built and social environment. After adjusting for individual variables, trust and social cohesion, two key social capital components were the only factors to show statistically significant associations with GHQ-12 scores. However, these factors also showed little variation at postcode levels, suggesting a stronger individual determination. We conclude that our results provide some evidence in support of an association between mental health (GHQ-12 scores) and perceptions of social capital, but less support for the contextual nature of social capital.

Footprints in the Sand: Personal, Psychological, and Relational Profiles of Religious, Spiritual, and Atheist LGB Individuals.

PubMed

Foster, Aasha B; Brewster, Melanie E; Velez, Brandon L; Eklund, Austin; Keum, Brian T

2017-01-01

The present study offers a comparison of the demographic features and lived experiences of lesbian, gay, and bisexual (LGB) individuals with religious, spiritual, or atheist (R/S/A) belief systems. In this sample of 212 participants, the relationship of participants' R/S/A beliefs to personal variables (e.g., age, gender, race), mental health variables (e.g., life satisfaction, psychological distress, internalized heterosexism, self-esteem), and relational variables (e.g., outness, connection to LGBTQ communities) were assessed. Correlational analyses indicated that level of R/S/A belief was unrelated to self-esteem, life satisfaction, or psychological distress; however, greater religious belief was correlated positively and significantly with internalized heterosexism and outness as LGB. To test the interactions of R/S/A beliefs and categorical variables of interest (e.g., race), log-linear analyses with follow-up chi-square tests were conducted. Findings suggested more similarities than differences for LGB people across R/S/A systems of belief. Limitations and implications for future research are discussed.

Exploration of an oculometer-based model of pilot workload

NASA Technical Reports Server (NTRS)

Krebs, M. J.; Wingert, J. W.; Cunningham, T.

1977-01-01

Potential relationships between eye behavior and pilot workload are discussed. A Honeywell Mark IIA oculometer was used to obtain the eye data in a fixed base transport aircraft simulation facility. The data were analyzed to determine those parameters of eye behavior which were related to changes in level of task difficulty of the simulated manual approach and landing on instruments. A number of trends and relationships between eye variables and pilot ratings were found. A preliminary equation was written based on the results of a stepwise linear regression. High variability in time spent on various instruments was related to differences in scanning strategy among pilots. A more detailed analysis of individual runs by individual pilots was performed to investigate the source of this variability more closely. Results indicated a high degree of intra-pilot variability in instrument scanning. No consistent workload related trends were found. Pupil diameter which had demonstrated a strong relationship to task difficulty was extensively re-exmained.

Development of a cross-cultural deprivation index in five European countries.

PubMed

Guillaume, Elodie; Pornet, Carole; Dejardin, Olivier; Launay, Ludivine; Lillini, Roberto; Vercelli, Marina; Marí-Dell'Olmo, Marc; Fernández Fontelo, Amanda; Borrell, Carme; Ribeiro, Ana Isabel; Pina, Maria Fatima de; Mayer, Alexandra; Delpierre, Cyrille; Rachet, Bernard; Launoy, Guy

2016-05-01

Despite a concerted policy effort in Europe, social inequalities in health are a persistent problem. Developing a standardised measure of socioeconomic level across Europe will improve the understanding of the underlying mechanisms and causes of inequalities. This will facilitate developing, implementing and assessing new and more effective policies, and will improve the comparability and reproducibility of health inequality studies among countries. This paper presents the extension of the European Deprivation Index (EDI), a standardised measure first developed in France, to four other European countries-Italy, Portugal, Spain and England, using available 2001 and 1999 national census data. The method previously tested and validated to construct the French EDI was used: first, an individual indicator for relative deprivation was constructed, defined by the minimal number of unmet fundamental needs associated with both objective (income) poverty and subjective poverty. Second, variables available at both individual (European survey) and aggregate (census) levels were identified. Third, an ecological deprivation index was constructed by selecting the set of weighted variables from the second step that best correlated with the individual deprivation indicator. For each country, the EDI is a weighted combination of aggregated variables from the national census that are most highly correlated with a country-specific individual deprivation indicator. This tool will improve both the historical and international comparability of studies, our understanding of the mechanisms underlying social inequalities in health and implementation of intervention to tackle social inequalities in health. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Explaining racial/ethnic differences in adolescent substance abuse treatment completion in the United States: a decomposition analysis.

PubMed

Saloner, Brendan; Carson, Nicholas; Lê Cook, Benjamin

2014-06-01

To identify contributors to racial/ethnic differences in completion of alcohol and marijuana treatment among adolescents at publicly funded providers. The 2007 Treatment Episode Data Set provided substance use history, treatment setting, and treatment outcomes for youth aged 12-17 years from five racial/ethnic groups (N = 67,060). Individual-level records were linked to variables measuring the social context and service system characteristics of the metropolitan area. We implemented nonlinear regression decomposition to identify variables that explained minority-white differences. Black and Hispanic youth were significantly less likely than whites to complete treatment for both alcohol and marijuana. Completion rates were similar for whites, Native Americans, and Asian-Americans, however. Differences in predictor variables explained 12.7% of the black-white alcohol treatment gap and 7.6% of the marijuana treatment gap. In contrast, predictors explained 57.4% of the Hispanic-white alcohol treatment gap and 19.8% of the marijuana treatment gap. While differences in the distribution of individual-level variables explained little of the completion gaps, metropolitan-level variables substantially contributed to Hispanic-white gaps. For example, racial/ethnic composition of the metropolitan area explained 41.0% of the Hispanic-white alcohol completion gap and 23.2% of the marijuana completion gap. Regional differences in addiction treatment financing (particularly use of Medicaid funding) explained 13.7% of the Hispanic-white alcohol completion gap and 9.8% of the Hispanic-white marijuana treatment completion gap. Factors related to social context are likely to be important contributors to white-minority differences in addiction treatment completion, particularly for Hispanic youth. Increased Medicaid funding, coupled with culturally tailored services, could be particularly beneficial. Copyright © 2014 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Morals or markets? Regulating assisted reproductive technologies as morality or economic policies in the states.

PubMed

Heidt-Forsythe, Erin

2017-01-01

The availability of assisted reproductive technologies (ARTs) in the medical marketplace complicates our understanding of reproductive public policy in the United States. Political debates over ARTs often are based on fundamental moral principles of life, reproduction, and kinship, similar to other reproductive policies in the United States. However, ARTs are an important moneymaking private enterprise for the U.S. biotechnology industry. This project investigates how the U.S. states regulate these unique and challenging technologies as either moral policies or economic policies. This study employs ordinary least squares (OLS) regression to estimate the significance of morality and economic policy variables on ART policies at the state level, noting associations between state-level political, economic, and gender variables on restrictive and permissive state-level ART policies. Economic variables (reflecting the biotechnology industry) and advocacy for access to ART on behalf of infertility patients increase the chances of states passing policies that enable consumer use of ARTs. Additionally, individual ART policies are distinct from one another in the ways that morality variables increase the chances of ART regulations. Surprisingly, the role of religious adherence among state residents varied in positive and negative relationships with individual policy passage. In general, these results support the hypothesis that ART laws are associated with economic as well as moral concerns of the states-ARTs lie at the intersection of issues of life and reproduction and of scientific innovation and health. What is most striking about these results is that they do not follow patterns seen in the legislation of abortion, contraception, and sexuality in general-those reproductive policies that are considered "morality policy." Similarly, economic variables are not consistently significant in the expected direction.

Exploring the relationship between hypoplasia and odontometric asymmetry in Isola Sacra, an imperial Roman necropolis.

PubMed

Hoover, Kara C; Corruccini, Robert S; Bondioli, Luca; Macchiarelli, Roberto

2005-01-01

Anthropological studies reporting odontometric asymmetry values or dental enamel hypoplasia frequencies use these markers as a record of physiological perturbations occurring during dental development. While both markers indirectly suggest the amount of relative stress a population might have experienced, a relationship between the two has been explored only recently in the literature. In this study, we address the possibility of such a relationship in two ways. First, Kendall's tau B correlations test the degree of relationship on the level of the individual between hypoplasia presence/absence (P/A) and severity of hypoplasia appearance (PS) data for the anterior dentition and directional (DA) and fluctuating asymmetry (FA) data for concurrently developing molars pairs. Second, an F-test explores between-group (ranked hypoplastic individuals and non-hypoplastic individuals) variance about the mean, expecting the hypoplastic individuals to be more variable. The sample consists of 72 individuals from the Isola Sacra necropolis, which is associated with Portus, the port city of ancient Rome. Results indicated only a very weak predictive relationship between some variables and few significant differences in variation. However, variance follows trends in published literature. Possible explanations for the lack of interaction on the level of the individual include both etiological and genetic susceptibility factors that are significant in and of themselves as they suggest a more complex reading of the hard tissue evidence for stress in archaeological populations. Copyright 2005 Wiley-Liss, Inc

How do anthropogenic contaminants (ACs) affect behaviour? Multi-level analysis of the effects of copper on boldness in hermit crabs.

PubMed

White, Stephen J; Briffa, Mark

2017-02-01

Natural animal populations are increasingly exposed to human impacts on the environment, which could have consequences for their behaviour. Among these impacts is exposure to anthropogenic contaminants. Any environmental variable that influences internal state could impact behaviour across a number of levels: at the sample mean, at the level of among-individual differences in behaviour ('animal personality') and at the level of within-individual variation in behaviour (intra-individual variation, 'IIV'). Here we examined the effect of exposure to seawater-borne copper on the startle response behaviour of European hermit crabs, Pagurus bernhardus across these levels. Copper exposure rapidly led to longer startle responses on average, but did not lead to any change in repeatability indicating that individual differences were present and equally consistent in the presence and absence of copper. There was no strong evidence that copper exposure led to changes in IIV. Our data show that exposure to copper for 1 week produces sample mean level changes in the behaviour of hermit crabs. However, there is no evidence that this exposure led to changes in repeatability through feedback loops.

[Ecological Correlates of Cardiovascular Disease Risk in Korean Blue-collar Workers: A Multi-level Study].

PubMed

Hwang, Won Ju; Park, Yunhee

2015-12-01

The purpose of this study was to investigate individual and organizational level of cardiovascular disease (CVD) risk factors associated with CVD risk in Korean blue-collar workers working in small sized companies. Self-report questionnaires and blood sampling for lipid and glucose were collected from 492 workers in 31 small sized companies in Korea. Multilevel modeling was conducted to estimate effects of related factors at the individual and organizational level. Multilevel regression analysis showed that workers in the workplace having a cafeteria had 1.81 times higher CVD risk after adjusting for factors at the individual level (p=.022). The explanatory power of variables related to organizational level variances in CVD risk was 17.1%. The results of this study indicate that differences in the CVD risk were related to organizational factors. It is necessary to consider not only individual factors but also organizational factors when planning a CVD risk reduction program. The factors caused by having cafeteria in the workplace can be reduced by improvement in the CVD-related risk environment, therefore an organizational-level intervention approach should be available to reduce CVD risk of workers in small sized companies in Korea.

Social determinants of denture/bridge use: Japan gerontological evaluation study project cross-sectional study in older Japanese.

PubMed

Yamamoto, Tatsuo; Kondo, Katsunori; Aida, Jun; Suzuki, Kayo; Misawa, Jimpei; Nakade, Miyo; Fuchida, Shinya; Hirata, Yukio

2014-06-03

Studies suggest that using a denture/bridge may prevent disability in older people. However, not all older people with few remaining teeth use a denture/bridge. This cross-sectional study aimed to examine the social determinants which promote denture/bridge use among older Japanese. A total of 54,388 (25,630 males and 28,758 females) community-dwelling individuals aged 65 or over, living independently, able to perform daily activities, and with 19 or fewer teeth. The dependent variable was denture/bridge use. Socio-demographics, number of teeth, present illness, social participation, social support, and social networks were used as individual-level independent variables. Data for social capital were aggregated and used as local district (n = 561 for males, n = 562 for females) -level independent variables. Number of dentists working in hospitals/clinics per population and population density were used as municipality (n = 28) -level independent variables. Three-level multilevel Poisson regression analysis was performed for each sex. High equivalent income, low number of teeth, present illness, and living in a municipality with high population density were significantly associated with denture/bridge use in both sexes in the fully adjusted models (p < 0.05). Denture/bridge use was significantly associated with high educational attainment in males and participating in social groups in females in the fully adjusted model (p < 0.05). No significant associations were observed between denture/bridge use and social capital. Denture/bridge use was significantly associated with high economic status and present illness in both sexes, high educational attainment in males, and participation in social groups in females among community-dwelling older Japanese after adjusting for possible confounders.

Variability in negative emotions among individuals with chronic low back pain: relationships with pain and function.

PubMed

Gerhart, James I; Burns, John W; Bruehl, Stephen; Smith, David A; Post, Kristina M; Porter, Laura S; Schuster, Erik; Buvanendran, Asokumar; Fras, Anne Marie; Keefe, Francis J

2017-11-13

Chronic pain is associated with elevated negative emotions, and resources needed to adaptively regulate these emotions can be depleted during prolonged pain. Studies of links between pain, function, and negative emotions in people with chronic pain, however, have focused almost exclusively on relationships among mean levels of these factors. Indexes that may reflect aspects of emotion regulation have typically not been analyzed. We propose that 1 index of emotion regulation is variability in emotion over time as opposed to average emotion over time. The sample was 105 people with chronic low back pain and 105 of their pain-free spouses. They completed electronic diary measures 5x/d for 14 consecutive days, producing 70 observations per person from which we derived estimates of within-subject variance in negative emotions. Location-scale models were used to simultaneously model predictors of both mean level and variance in patient negative emotions over time. Patients reported significantly more variability in negative emotions compared to their spouses. Patients who reported higher average levels of pain, pain interference, and downtime reported significantly higher levels of variability in negative emotions. Spouse-observed pain and pain behaviors were also associated with greater variability in patients' negative emotions. Test of the inverse associations between negative emotion level and variability in pain and function were significant but weaker in magnitude. These findings support the notion that chronic pain may erode negative emotion regulation resources, to the potential detriment of intra- and inter-personal function.

Assessment of xylem phenology: a first attempt to verify its accuracy and precision.

PubMed

Lupi, C; Rossi, S; Vieira, J; Morin, H; Deslauriers, A

2014-01-01

This manuscript aims to evaluate the precision and accuracy of current methodology for estimating xylem phenology and tracheid production in trees. Through a simple approach, sampling at two positions on the stem of co-dominant black spruce trees in two sites of the boreal forest of Quebec, we were able to quantify variability among sites, between trees and within a tree for different variables. We demonstrated that current methodology is accurate for the estimation of the onset of xylogenesis, while the accuracy for the evaluation of the ending of xylogenesis may be improved by sampling at multiple positions on the stem. The pattern of variability in different phenological variables and cell production allowed us to advance a novel hypothesis on the shift in the importance of various drivers of xylogenesis, from factors mainly varying at the level of site (e.g., climate) at the beginning of the growing season to factors varying at the level of individual trees (e.g., possibly genetic variability) at the end of the growing season.

Coexisting with dependence and well-being: the results of a pilot study intervention on 75-99-year-old individuals.

PubMed

Rodríguez-Díaz, M Teresa; Pérez-Marfil, M Nieves; Cruz-Quintana, Francisco

2016-12-01

The objective of this study is to design and implement an intervention program centered on preventing functional dependence. A pre/post quasi-experimental (typical case) design study with a control group was conducted on a group of 75-90-year-old individuals with functional dependence (n = 59) at three nursing homes in Madrid (Spain). The intervention program consists of two types of activities developed simultaneously. Some focused on emotional well-being (nine 90-minute sessions, once per week), whereas others focused on improving participants' physical condition (two 30-minute sessions, twice per week). The simple randomized participants included 59 elderly individuals (Intervention Group = 30, Control Group = 29) (mean age 86.80) [SD, 5. 19]. Fifty-nine participants were analyzed. The results indicate that the program is effective in improving mood, lowering anxiety levels (d = 0.81), and increasing both self-esteem (d = 0.65) and the perception of self-efficacy (d = 1.04). There are improvements in systolic pressure and functional dependence levels are maintained. Linear simple regression (independent variable pre-Barthel) shows that the pre-intervention dependence level can predict self-esteem after the intervention. We have demonstrated that the program is innovative with regard to bio-psychosocial care in elderly individuals, is based on actual practice, and is effective in increasing both self-esteem and self-efficacy. These variables positively affect functional capabilities and delay functional dependence.

Gender, Emotion Work, and Relationship Quality: A Daily Diary Study.

PubMed

Curran, Melissa A; McDaniel, Brandon T; Pollitt, Amanda M; Totenhagen, Casey J

2015-08-01

We use the gender relations perspective from feminist theorizing to investigate how gender and daily emotion work predict daily relationship quality in 74 couples (148 individuals in dating, cohabiting, or married relationships) primarily from the southwest U.S. Emotion work is characterized by activities that enhance others' emotional well-being. We examined emotion work two ways: trait (individuals' average levels) and state (individuals' daily fluctuations). We examined actor and partner effects of emotion work and tested for gender differences. As outcome variables, we included six types of daily relationship quality: love, commitment, satisfaction, closeness, ambivalence, and conflict. This approach allowed us to predict three aspects of relationship quality: average levels, daily fluctuations, and volatility (overall daily variability across a week). Three patterns emerged. First, emotion work predicted relationship quality in this diverse set of couples. Second, gender differences were minimal for fixed effects: Trait and state emotion work predicted higher average scores on, and positive daily increases in, individuals' own positive relationship quality and lower average ambivalence. Third, gender differences were more robust for volatility: For partner effects, having a partner who reported higher average emotion work predicted lower volatility in love, satisfaction, and closeness for women versus greater volatility in love and commitment for men. Neither gender nor emotion work predicted average levels, daily fluctuations, or volatility in conflict. We discuss implications and future directions pertaining to the unique role of gender in understanding the associations between daily emotion work and volatility in daily relationship quality for relational partners.

Exercise, nutrition, and homocysteine.

PubMed

Joubert, Lanae M; Manore, Melinda M

2006-08-01

Homocysteine is an independent cardiovascular disease (CVD) risk factor modifiable by nutrition and possibly exercise. While individuals participating in regular physical activity can modify CVD risk factors, such as total blood cholesterol levels, the impact physical activity has on blood homocysteine concentrations is unclear. This review examines the influence of nutrition and exercise on blood homocysteine levels, the mechanisms of how physical activity may alter homocysteine levels, the role of homocysteine in CVD, evidence to support homocysteine as an independent risk factor for CVD, mechanisms of how homocysteine increases CVD risk, and cut-off values for homocysteinemia. Research examining the impact of physical activity on blood homocysteine levels is equivocal, which is partially due to a lack of control for confounding variables that impact homocysteine. Duration, intensity, and mode of exercise appear to impact blood homocysteine levels differently, and may be dependent on individual fitness levels.

Conservation physiology for applied management of marine fish: an overview with perspectives on the role and value of telemetry

PubMed Central

Metcalfe, J. D.; Le Quesne, W. J. F.; Cheung, W. W. L.; Righton, D. A.

2012-01-01

Physiological studies focus on the responses of cells, tissues and individuals to stressors, usually in laboratory situations. Conservation and management, on the other hand, focus on populations. The field of conservation physiology addresses the question of how abiotic drivers of physiological responses at the level of the individual alter requirements for successful conservation and management of populations. To achieve this, impacts of physiological effects at the individual level need to be scaled to impacts on population dynamics, which requires consideration of ecology. Successfully realizing the potential of conservation physiology requires interdisciplinary studies incorporating physiology and ecology, and requires that a constructive dialogue develops between these traditionally disparate fields. To encourage this dialogue, we consider the increasingly explicit incorporation of physiology into ecological models applied to marine fish conservation and management. Conservation physiology is further challenged as the physiology of an individual revealed under laboratory conditions is unlikely to reflect realized responses to the complex variable stressors to which it is exposed in the wild. Telemetry technology offers the capability to record an animal's behaviour while simultaneously recording environmental variables to which it is exposed. We consider how the emerging insights from telemetry can strengthen the incorporation of physiology into ecology. PMID:22566680

Neural network configuration and efficiency underlies individual differences in spatial orientation ability.

PubMed

Arnold, Aiden E G F; Protzner, Andrea B; Bray, Signe; Levy, Richard M; Iaria, Giuseppe

2014-02-01

Spatial orientation is a complex cognitive process requiring the integration of information processed in a distributed system of brain regions. Current models on the neural basis of spatial orientation are based primarily on the functional role of single brain regions, with limited understanding of how interaction among these brain regions relates to behavior. In this study, we investigated two sources of variability in the neural networks that support spatial orientation--network configuration and efficiency--and assessed whether variability in these topological properties relates to individual differences in orientation accuracy. Participants with higher accuracy were shown to express greater activity in the right supramarginal gyrus, the right precentral cortex, and the left hippocampus, over and above a core network engaged by the whole group. Additionally, high-performing individuals had increased levels of global efficiency within a resting-state network composed of brain regions engaged during orientation and increased levels of node centrality in the right supramarginal gyrus, the right primary motor cortex, and the left hippocampus. These results indicate that individual differences in the configuration of task-related networks and their efficiency measured at rest relate to the ability to spatially orient. Our findings advance systems neuroscience models of orientation and navigation by providing insight into the role of functional integration in shaping orientation behavior.

Static Prehension of a Horizontally Oriented Object in Three Dimensions

PubMed Central

Wu, Yen-Hsun; Zatsiorsky, Vladimir M.; Latash, Mark L.

2011-01-01

We studied static prehension of a horizontally oriented object. Specific hypotheses were explored addressing such issues as the sharing patterns of the total moment of force across the digits, presence of mechanically unnecessary digit forces, and trade-off between multi-digit synergies at the two levels of the assumed control hierarchy. Within the assumed hierarchy, at the upper level, the task is shared between the thumb and virtual finger (an imagined finger producing a wrench equal to the sum of the wrenches of individual fingers). At the lower level, action of the virtual finger is shared among the four actual fingers. The subjects held statically a horizontally oriented handle instrumented with six-component force/torque sensors with different loads and torques acting about the long axis of the handle. The thumb acted from above while the four fingers supported the weight of the object. When the external torque was zero, the thumb produced mechanically unnecessary force of about 2.8 N, which did not depend on the external load magnitude. When the external torque was not zero, tangential forces produced over 80% of the total moment of force. The normal forces by the middle and ring fingers produced consistent moments against the external torque, while the normal forces of the index and little fingers did not. Force and moment variables at both hierarchical levels were stabilized by co-varied across trials adjustments of forces/moments produced by individual digits with the exception of the normal force analyzed at the lower level of the hierarchy. There was a trade-off between synergy indices computed at the two levels of the hierarchy for the three components of the total force vector, but not for the moment of force components. Overall, the results have shown that task mechanics are only one factor that defines forces produced by individual digits. Other factors, such as loading sensory receptors may lead to mechanically unnecessary forces. There seems to be no single rule (for example, ensuring similar safety margin values) that would describe sharing of the normal and tangential forces and be valid across tasks. Fingers that are traditionally viewed as less accurate (e.g., the ring finger) may perform more consistently in certain tasks. The observations of the trade-off between the synergy indices computed at two levels for the force variables but not for the moment of force variables suggest that the degree of redundancy (the number of excessive elemental variables) at the higher level is an important factor. PMID:22071684

Temporal variability in lipoprotein(a) levels in patients enrolled in the placebo arms of IONIS-APO(a)Rx and IONIS-APO(a)-LRx antisense oligonucleotide clinical trials.

PubMed

Marcovina, Santica M; Viney, Nicholas J; Hughes, Steven G; Xia, Shuting; Witztum, Joseph L; Tsimikas, Sotirios

Lipoprotein(a) [Lp(a)] levels are primarily genetically determined, but their natural variability is not well known. The aim of the study was to evaluate the short-term temporal variability in Lp(a) in 3 placebo groups from the IONIS-APO(a) Rx and IONIS-APO(a)-L Rx trials. The placebo groups comprised 3 studies: Study 1 with 10 subjects with any Lp(a) concentration; Study 2 with 13 subjects with Lp(a) ≥75 nmol/L (∼30 mg/dL); and Study 3 with 29 patients with Lp(a) ≥125 nmol/L (≥∼50 mg/dL). Lp(a) was measured in serial blood samples (range 7-12 samples up to 190 days of follow-up) and analyzed as absolute change and mean percent change from baseline. Outliers were defined as having a > ±25% difference in Lp(a) from baseline at any future time point. No significant temporal differences in mean absolute Lp(a) levels were present in any group. However, among individuals, the mean change in absolute Lp(a) levels at any time point ranged from -16.2 to +7.0 nmol/L in Study 1, -15.8 to +9.8 nmol/L in Study 2, and -60.2 to +16.6 nmol/L in Study 3. The mean percent change from baseline ranged from -9.4% to +21.6% for Study 1, -13.1% to 2.8% for Study 2, and -12.1% to +4.9% in Study 3. A total of 21 of 52 subjects (40.4%) were outliers, with 13 (62%) >25% up and 8 (38%) >25% down. Significant variability was also noted in other lipid parameters, but no outliers were noted with serum albumin. In subjects randomized to placebo in Lp(a) lowering trials, modest intra-individual temporal variability of mean Lp(a) levels was present. Significant number of subjects had > ±25% variation in Lp(a) in at least 1 time point. Although Lp(a) levels are primarily genetically determined, further study is required to define additional factors mediating short-term variability. Copyright © 2017 National Lipid Association. Published by Elsevier Inc. All rights reserved.

A person based formula for allocating commissioning funds to general practices in England: development of a statistical model.

PubMed

Dixon, Jennifer; Smith, Peter; Gravelle, Hugh; Martin, Steve; Bardsley, Martin; Rice, Nigel; Georghiou, Theo; Dusheiko, Mark; Billings, John; Lorenzo, Michael De; Sanderson, Colin

2011-11-22

To develop a formula for allocating resources for commissioning hospital care to all general practices in England based on the health needs of the people registered in each practice Multivariate prospective statistical models were developed in which routinely collected electronic information from 2005-6 and 2006-7 on individuals and the areas in which they lived was used to predict their costs of hospital care in the next year, 2007-8. Data on individuals included all diagnoses recorded at any inpatient admission. Models were developed on a random sample of 5 million people and validated on a second random sample of 5 million people and a third sample of 5 million people drawn from a random sample of practices. All general practices in England as of 1 April 2007. All NHS inpatient admissions and outpatient attendances for individuals registered with a general practice on that date. All individuals registered with a general practice in England at 1 April 2007. Power of the statistical models to predict the costs of the individual patient or each practice's registered population for 2007-8 tested with a range of metrics (R(2) reported here). Comparisons of predicted costs in 2007-8 with actual costs incurred in the same year were calculated by individual and by practice. Models including person level information (age, sex, and ICD-10 codes diagnostic recorded) and a range of area level information (such as socioeconomic deprivation and supply of health facilities) were most predictive of costs. After accounting for person level variables, area level variables added little explanatory power. The best models for resource allocation could predict upwards of 77% of the variation in costs at practice level, and about 12% at the person level. With these models, the predicted costs of about a third of practices would exceed or undershoot the actual costs by 10% or more. Smaller practices were more likely to be in these groups. A model was developed that performed well by international standards, and could be used for allocations to practices for commissioning. The best formulas, however, could predict only about 12% of the variation in next year's costs of most inpatient and outpatient NHS care for each individual. Person-based diagnostic data significantly added to the predictive power of the models.

The association of neighbourhood and individual social capital with consistent self-rated health: a longitudinal study in Brazilian pregnant and postpartum women

PubMed Central

2013-01-01

Background Social conditions, social relationships and neighbourhood environment, the components of social capital, are important determinants of health. The objective of this study was to investigate the association of neighbourhood and individual social capital with consistent self-rated health in women between the first trimester of pregnancy and six months postpartum. Methods A multilevel cohort study in 34 neighbourhoods was performed on 685 Brazilian women recruited at antenatal units in two cities in the State of Rio de Janeiro, Brazil. Self-rated health (SRH) was assessed in the 1st trimester of pregnancy (baseline) and six months after childbirth (follow-up). The participants were divided into two groups: 1. Good SRH – good SRH at baseline and follow-up, and, 2. Poor SRH – poor SRH at baseline and follow-up. Exploratory variables collected at baseline included neighbourhood social capital (neighbourhood-level variable), individual social capital (social support and social networks), demographic and socioeconomic characteristics, health-related behaviours and self-reported diseases. A hierarchical binomial multilevel analysis was performed to test the association between neighbourhood and individual social capital and SRH, adjusted for covariates. Results The Good SRH group reported higher scores of social support and social networks than the Poor SRH group. Although low neighbourhood social capital was associated with poor SRH in crude analysis, the association was not significant when individual socio-demographic variables were included in the model. In the final model, women reporting poor SRH both at baseline and follow-up had lower levels of social support (positive social interaction) [OR 0.82 (95% CI: 0.73-0.90)] and a lower likelihood of friendship social networks [OR 0.61 (95% CI: 0.37-0.99)] than the Good SRH group. The characteristics that remained associated with poor SRH were low level of schooling, Black and Brown ethnicity, more children, urinary infection and water plumbing outside the house. Conclusions Low individual social capital during pregnancy, considered here as social support and social network, was independently associated with poor SRH in women whereas neighbourhood social capital did not affect women’s SRH during pregnancy and the months thereafter. From pregnancy and up to six months postpartum, the effect of individual social capital explained better the consistency of SRH over time than neighbourhood social capital. PMID:23324161

The association of neighbourhood and individual social capital with consistent self-rated health: a longitudinal study in Brazilian pregnant and postpartum women.

PubMed

Lamarca, Gabriela A; do C Leal, Maria; Sheiham, Aubrey; Vettore, Mario V

2013-01-16

Social conditions, social relationships and neighbourhood environment, the components of social capital, are important determinants of health. The objective of this study was to investigate the association of neighbourhood and individual social capital with consistent self-rated health in women between the first trimester of pregnancy and six months postpartum. A multilevel cohort study in 34 neighbourhoods was performed on 685 Brazilian women recruited at antenatal units in two cities in the State of Rio de Janeiro, Brazil. Self-rated health (SRH) was assessed in the 1st trimester of pregnancy (baseline) and six months after childbirth (follow-up). The participants were divided into two groups: 1. Good SRH--good SRH at baseline and follow-up, and, 2. Poor SRH--poor SRH at baseline and follow-up. Exploratory variables collected at baseline included neighbourhood social capital (neighbourhood-level variable), individual social capital (social support and social networks), demographic and socioeconomic characteristics, health-related behaviours and self-reported diseases. A hierarchical binomial multilevel analysis was performed to test the association between neighbourhood and individual social capital and SRH, adjusted for covariates. The Good SRH group reported higher scores of social support and social networks than the Poor SRH group. Although low neighbourhood social capital was associated with poor SRH in crude analysis, the association was not significant when individual socio-demographic variables were included in the model. In the final model, women reporting poor SRH both at baseline and follow-up had lower levels of social support (positive social interaction) [OR 0.82 (95% CI: 0.73-0.90)] and a lower likelihood of friendship social networks [OR 0.61 (95% CI: 0.37-0.99)] than the Good SRH group. The characteristics that remained associated with poor SRH were low level of schooling, Black and Brown ethnicity, more children, urinary infection and water plumbing outside the house. Low individual social capital during pregnancy, considered here as social support and social network, was independently associated with poor SRH in women whereas neighbourhood social capital did not affect women's SRH during pregnancy and the months thereafter. From pregnancy and up to six months postpartum, the effect of individual social capital explained better the consistency of SRH over time than neighbourhood social capital.

Individual and family environmental correlates of television and computer time in 10- to 12-year-old European children: the ENERGY-project.

PubMed

Verloigne, Maïté; Van Lippevelde, Wendy; Bere, Elling; Manios, Yannis; Kovács, Éva; Grillenberger, Monika; Maes, Lea; Brug, Johannes; De Bourdeaudhuij, Ilse

2015-09-18

The aim was to investigate which individual and family environmental factors are related to television and computer time separately in 10- to-12-year-old children within and across five European countries (Belgium, Germany, Greece, Hungary, Norway). Data were used from the ENERGY-project. Children and one of their parents completed a questionnaire, including questions on screen time behaviours and related individual and family environmental factors. Family environmental factors included social, political, economic and physical environmental factors. Complete data were obtained from 2022 child-parent dyads (53.8 % girls, mean child age 11.2 ± 0.8 years; mean parental age 40.5 ± 5.1 years). To examine the association between individual and family environmental factors (i.e. independent variables) and television/computer time (i.e. dependent variables) in each country, multilevel regression analyses were performed using MLwiN 2.22, adjusting for children's sex and age. In all countries, children reported more television and/or computer time, if children and their parents thought that the maximum recommended level for watching television and/or using the computer was higher and if children had a higher preference for television watching and/or computer use and a lower self-efficacy to control television watching and/or computer use. Most physical and economic environmental variables were not significantly associated with television or computer time. Slightly more individual factors were related to children's computer time and more parental social environmental factors to children's television time. We also found different correlates across countries: parental co-participation in television watching was significantly positively associated with children's television time in all countries, except for Greece. A higher level of parental television and computer time was only associated with a higher level of children's television and computer time in Hungary. Having rules regarding children's television time was related to less television time in all countries, except for Belgium and Norway. Most evidence was found for an association between screen time and individual and parental social environmental factors, which means that future interventions aiming to reduce screen time should focus on children's individual beliefs and habits as well parental social factors. As we identified some different correlates for television and computer time and across countries, cross-European interventions could make small adaptations per specific screen time activity and lay different emphases per country.

Different Types of Sensation Seeking: A Person-Oriented Approach in Sensation-Seeking Research

ERIC Educational Resources Information Center

Suranyi, Zsuzsanna; Hitchcock, David B.; Hittner, James B.; Vargha, Andras; Urban, Robert

2013-01-01

Previous research on sensation seeking (SS) was dominated by a variable-oriented approach indicating that SS level has a linear relation with a host of problem behaviors. Our aim was to provide a person-oriented methodology--a probabilistic clustering--that enables examination of both inter- and intra-individual differences in not only the level,…

Analysis of Self-Esteem Levels of Students in Physical Education and Sports High School

ERIC Educational Resources Information Center

çakoyun, Fahri Ak

2018-01-01

The purpose of this study is to examine the self-esteem levels of the students at Balikesir University Physical Education and Sports High School according to the variables such; gender, age, body-mass index (BMI), education department, class, sporting situation and sport branch (individual sport-team sport). While the universe of the study has…

Evaluation of Model Specification, Variable Selection, and Adjustment Methods in Relation to Propensity Scores and Prognostic Scores in Multilevel Data

ERIC Educational Resources Information Center

Yu, Bing; Hong, Guanglei

2012-01-01

This study uses simulation examples representing three types of treatment assignment mechanisms in data generation (the random intercept and slopes setting, the random intercept setting, and a third setting with a cluster-level treatment and an individual-level outcome) in order to determine optimal procedures for reducing bias and improving…

The Effects of Blood Alcohol Levels on Driving Variables in a High-Risk Population: Objective and Subjective Measures.

ERIC Educational Resources Information Center

Cox, Daniel J.; And Others

1995-01-01

Assessed high-risk individuals' subjective awareness of legal intoxication and ability to drive, and objectively quantified their blood alcohol levels and driving performance. While subjects were able to recognize legal intoxication, one-third of the subjects were still willing to drive after becoming intoxicated beyond the legal limit to drive.…

Single-Participant Assessment of Treatment Mediators: Strategy Description and Examples from a Behavioral Activation Intervention for Depressed Adolescents

ERIC Educational Resources Information Center

Gaynor, Scott T.; Harris, Amanda

2008-01-01

Determining the means by which effective psychotherapy works is critical. A generally recommended strategy for identifying the potential causal variables is to conduct group-level statistical tests of treatment mediators. Herein the case is made for also assessing mediators of treatment outcome at the level of the individual participant.…

Effects of complex aural stimuli on mental performance.

PubMed

Vij, Mohit; Aghazadeh, Fereydoun; Ray, Thomas G; Hatipkarasulu, Selen

2003-06-01

The objective of this study is to investigate the effect of complex aural stimuli on mental performance. A series of experiments were designed to obtain data for two different analyses. The first analysis is a "Stimulus" versus "No-stimulus" comparison for each of the four dependent variables, i.e. quantitative ability, reasoning ability, spatial ability and memory of an individual, by comparing the control treatment with the rest of the treatments. The second set of analysis is a multi-variant analysis of variance for component level main effects and interactions. The two component factors are tempo of the complex aural stimuli and sound volume level, each administered at three discrete levels for all four dependent variables. Ten experiments were conducted on eleven subjects. It was found that complex aural stimuli influence the quantitative and spatial aspect of the mind, while the reasoning ability was unaffected by the stimuli. Although memory showed a trend to be worse with the presence of complex aural stimuli, the effect was statistically insignificant. Variation in tempo and sound volume level of an aural stimulus did not significantly affect the mental performance of an individual. The results of these experiments can be effectively used in designing work environments.

The Key Events Dose-Response Framework: a cross-disciplinary mode-of-action based approach to examining dose-response and thresholds.

PubMed

Julien, Elizabeth; Boobis, Alan R; Olin, Stephen S

2009-09-01

The ILSI Research Foundation convened a cross-disciplinary working group to examine current approaches for assessing dose-response and identifying safe levels of intake or exposure for four categories of bioactive agents-food allergens, nutrients, pathogenic microorganisms, and environmental chemicals. This effort generated a common analytical framework-the Key Events Dose-Response Framework (KEDRF)-for systematically examining key events that occur between the initial dose of a bioactive agent and the effect of concern. Individual key events are considered with regard to factors that influence the dose-response relationship and factors that underlie variability in that relationship. This approach illuminates the connection between the processes occurring at the level of fundamental biology and the outcomes observed at the individual and population levels. Thus, it promotes an evidence-based approach for using mechanistic data to reduce reliance on default assumptions, to quantify variability, and to better characterize biological thresholds. This paper provides an overview of the KEDRF and introduces a series of four companion papers that illustrate initial application of the approach to a range of bioactive agents.

Mindfulness and heart rate variability in individuals with high and low generalized anxiety symptoms.

PubMed

Mankus, Annette M; Aldao, Amelia; Kerns, Caroline; Mayville, Elena Wright; Mennin, Douglas S

2013-07-01

Mindfulness has been incorporated into several treatment approaches for psychopathology. Despite the popularity of this approach, relatively few empirical investigations have examined the relationship between mindfulness and autonomic indicators of flexible emotion regulation, such as heart rate variability (HRV). Generalized anxiety disorder (GAD) has been associated with both low levels of mindfulness and HRV. In this investigation, we examined the relationship between HRV and mindfulness in the context of elevated generalized anxiety (GA) symptoms--an analog for GAD--by examining whether GA level moderated this relationship. HRV was collected while participants completed self-report measures of GA and trait mindfulness. GA level interacted with mindfulness in the prediction of HRV; in the high GA, but not low GA group, mindfulness was positively associated with HRV. This suggests that for individuals with high GA, mindfulness may enhance parasympathetic influences on the heart rate. We address the limitations of the current investigation and suggest avenues for future research on mindfulness-related changes in tonic and phasic HRV over time. Copyright © 2013 Elsevier Ltd. All rights reserved.

Benchmarking dairy herd health status using routinely recorded herd summary data.

PubMed

Parker Gaddis, K L; Cole, J B; Clay, J S; Maltecca, C

2016-02-01

Genetic improvement of dairy cattle health through the use of producer-recorded data has been determined to be feasible. Low estimated heritabilities indicate that genetic progress will be slow. Variation observed in lowly heritable traits can largely be attributed to nongenetic factors, such as the environment. More rapid improvement of dairy cattle health may be attainable if herd health programs incorporate environmental and managerial aspects. More than 1,100 herd characteristics are regularly recorded on farm test-days. We combined these data with producer-recorded health event data, and parametric and nonparametric models were used to benchmark herd and cow health status. Health events were grouped into 3 categories for analyses: mastitis, reproductive, and metabolic. Both herd incidence and individual incidence were used as dependent variables. Models implemented included stepwise logistic regression, support vector machines, and random forests. At both the herd and individual levels, random forest models attained the highest accuracy for predicting health status in all health event categories when evaluated with 10-fold cross-validation. Accuracy (SD) ranged from 0.61 (0.04) to 0.63 (0.04) when using random forest models at the herd level. Accuracy of prediction (SD) at the individual cow level ranged from 0.87 (0.06) to 0.93 (0.001) with random forest models. Highly significant variables and key words from logistic regression and random forest models were also investigated. All models identified several of the same key factors for each health event category, including movement out of the herd, size of the herd, and weather-related variables. We concluded that benchmarking health status using routinely collected herd data is feasible. Nonparametric models were better suited to handle this complex data with numerous variables. These data mining techniques were able to perform prediction of health status and could add evidence to personal experience in herd management. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Comparison of basic physical fitness, aerobic capacity, and isokinetic strength between national and international level high school freestyle swimmers

PubMed Central

Bae, Young-Hyeon; Yu, Jae-Ho; Lee, Suk Min

2016-01-01

[Purpose] This study aimed to compare basic physical fitness, aerobic capacity, and isokinetic strength between international and national level freestyle high school student swimmers. [Subjects and Methods] A total of 28 participants (14 international level swimmers and 14 national level freestyle high school student swimmers) with no known pathology were included. We used a cross-sectional study to examine three variables: basic physical fitness, aerobic capacity, and isokinetic strength. [Results] The mean values of these variables in the international level swimmers were higher than those in the national level swimmers. Swimmers are generally physically fit with a good competition record. [Conclusion] An appropriate training program, which considers specific individual characteristics is likely to have a positive impact on the improvement of total physical fitness, and subsequently, on the performance of the freestyle high school swimmer. PMID:27134379

Human and methodological sources of variability in the measurement of urinary 8-oxo-7,8-dihydro-2'-deoxyguanosine.

PubMed

Barregard, Lars; Møller, Peter; Henriksen, Trine; Mistry, Vilas; Koppen, Gudrun; Rossner, Pavel; Sram, Radim J; Weimann, Allan; Poulsen, Henrik E; Nataf, Robert; Andreoli, Roberta; Manini, Paola; Marczylo, Tim; Lam, Patricia; Evans, Mark D; Kasai, Hiroshi; Kawai, Kazuaki; Li, Yun-Shan; Sakai, Kazuo; Singh, Rajinder; Teichert, Friederike; Farmer, Peter B; Rozalski, Rafal; Gackowski, Daniel; Siomek, Agnieszka; Saez, Guillermo T; Cerda, Concha; Broberg, Karin; Lindh, Christian; Hossain, Mohammad Bakhtiar; Haghdoost, Siamak; Hu, Chiung-Wen; Chao, Mu-Rong; Wu, Kuen-Yuh; Orhan, Hilmi; Senduran, Nilufer; Smith, Raymond J; Santella, Regina M; Su, Yali; Cortez, Czarina; Yeh, Susan; Olinski, Ryszard; Loft, Steffen; Cooke, Marcus S

2013-06-20

Urinary 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) is a widely used biomarker of oxidative stress. However, variability between chromatographic and ELISA methods hampers interpretation of data, and this variability may increase should urine composition differ between individuals, leading to assay interference. Furthermore, optimal urine sampling conditions are not well defined. We performed inter-laboratory comparisons of 8-oxodG measurement between mass spectrometric-, electrochemical- and ELISA-based methods, using common within-technique calibrants to analyze 8-oxodG-spiked phosphate-buffered saline and urine samples. We also investigated human subject- and sample collection-related variables, as potential sources of variability. Chromatographic assays showed high agreement across urines from different subjects, whereas ELISAs showed far more inter-laboratory variation and generally overestimated levels, compared to the chromatographic assays. Excretion rates in timed 'spot' samples showed strong correlations with 24 h excretion (the 'gold' standard) of urinary 8-oxodG (rp 0.67-0.90), although the associations were weaker for 8-oxodG adjusted for creatinine or specific gravity (SG). The within-individual excretion of 8-oxodG varied only moderately between days (CV 17% for 24 h excretion and 20% for first void, creatinine-corrected samples). This is the first comprehensive study of both human and methodological factors influencing 8-oxodG measurement, providing key information for future studies with this important biomarker. ELISA variability is greater than chromatographic assay variability, and cannot determine absolute levels of 8-oxodG. Use of standardized calibrants greatly improves intra-technique agreement and, for the chromatographic assays, importantly allows integration of results for pooled analyses. If 24 h samples are not feasible, creatinine- or SG-adjusted first morning samples are recommended.

The role of COMT and plasma proline in the variable penetrance of autistic spectrum symptoms in 22q11.2 deletion syndrome.

PubMed

Hidding, E; Swaab, H; de Sonneville, L M J; van Engeland, H; Vorstman, J A S

2016-11-01

This paper examines how COMT 158 genotypes and plasma proline levels are associated with variable penetrance of social behavioural and social cognitive problems in 22q11.2 deletion syndrome (22q11DS). Severity of autistic spectrum symptoms of 45 participants with 22q11DS was assessed using the Autism Diagnostic Interview Revised. Face and facial emotion recognition was evaluated using standardized computer-based test-paradigms. Associations with COMT 158 genotypes and proline levels were examined. High proline levels and poor face recognition in individuals with the COMT MET allele, and poor facial emotion recognition, explained almost 50% of the variance in severity of autism symptomatology in individuals with 22q11DS. High proline levels and a decreased capacity to break down dopamine as a result of the COMT MET variant are both relevant in the expression of the social phenotype in patients. This epistatic interaction effect between the COMT 158 genotype and proline on the expression of social deficits in 22q11DS shows how factors other than the direct effects of the deletion itself can modulate the penetrance of associated cognitive and behavioural outcomes. These findings are not only relevant to our insight into 22q11DS, but also provide a model to better understand the phenomenon of variable penetrance in other pathogenic genetic variants. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Cross-national differences in the gender gap in subjective health in Europe: does country-level gender equality matter?

PubMed

Dahlin, Johanna; Härkönen, Juho

2013-12-01

Multiple studies have found that women report being in worse health despite living longer. Gender gaps vary cross-nationally, but relatively little is known about the causes of comparative differences. Existing literature is inconclusive as to whether gender gaps in health are smaller in more gender equal societies. We analyze gender gaps in self-rated health (SRH) and limiting longstanding illness (LLI) with five waves of European Social Survey data for 191,104 respondents from 28 countries. We use means, odds ratios, logistic regressions, and multilevel random slopes logistic regressions. Gender gaps in subjective health vary visibly across Europe. In many countries (especially in Eastern and Southern Europe), women report distinctly worse health, while in others (such as Estonia, Finland, and Great Britain) there are small or no differences. Logistic regressions ran separately for each country revealed that individual-level socioeconomic and demographic variables explain a majority of these gaps in some countries, but contribute little to their understanding in most countries. In yet other countries, men had worse health when these variables were controlled for. Cross-national variation in the gender gaps exists after accounting for individual-level factors. Against expectations, the remaining gaps are not systematically related to societal-level gender inequality in the multilevel analyses. Our findings stress persistent cross-national variability in gender gaps in health and call for further analysis. Copyright © 2013 Elsevier Ltd. All rights reserved.

Individual differences in the day-to-day variability of pain, fatigue, and well-being in patients with rheumatic disease: Associations with psychological variables

PubMed Central

Schneider, Stefan; Junghaenel, Doerte U.; Keefe, Francis J.; Schwartz, Joseph E.; Stone, Arthur A.; Broderick, Joan E.

2012-01-01

This paper examines day-to-day variability in rheumatology patients' ratings of pain and related quality-of-life variables as well as predictors of that variability. Data from two studies were used. The hypothesis was that greater psychological distress (i.e., depression and anxiety) and poorer coping appraisals (i.e., higher pain catastrophizing and lower self-efficacy) are associated with more variability. Electronic daily diary ratings were collected from 106 patients from a community rheumatology practice across 28 days (Study 1), and from 194 osteoarthritis patients across 7 days (Study 2). In multilevel modeling analyses, substantial day-to-day variability was evident for all variables in both studies, andindividual patients differed considerably and somewhat reliably in the magnitude of their variability. Higher levels of depression significantly predicted greater variability in pain, as well as in happiness and frustration (Study 1). Lower self-efficacy was associated with more variability in patients' daily satisfaction with accomplishments and in the quality of their day (Study 2). Greater pain catastrophizing and higher depression predicted more variability in interference with social relationships (Study 2). Anxiety was not significantly associated with day-to-day variability. The results of these studies suggest that individual differences in the magnitude of symptom fluctuation may play a vital role in understanding patients' adjustment to pain. Future research will be needed to examine the clinical utility of measuring variability in patients' pain and well being, and to understand whether reducing variability may be an important treatment target. PMID:22349917

Differences between biological and chronological age-at-death in human skeletal remains: A change of perspective.

PubMed

Couoh, Lourdes R

2017-08-01

This analysis seeks to determine whether differences between real and estimated chronological age (CA) with biological age (BA) in skeletal individuals reflect variability in aging. A total of 87 individuals of two samples, ranging from 20 to 94 years old, were analyzed. One, partially documented, belongs to a Mexican skeletal collection dating to the 20th century; the other is an assemblage of prehispanic individuals from different archaeological sites. In all specimens, the tooth annulation method (TCA) was applied to estimate CA, while-excluding individuals older than 80 years-auricular surface (AS) and pubic symphysis (PS) methods were used to estimate BA. Statistical analyses were conducted to identify correlations and significance of the differences between CA vs. TCA, CA vs. AS/PS, TCA vs. AS/PS. Sex of individuals was assessed for its influence in aging. The use of TCA to estimate CA was successful for most individuals. A strong correlation was found between CA vs. TCA, CA vs. AS/PS, TCA vs. AS/PS and their differences were significant but variation in these were found when assessed by separate age groups. Sex did not influence such differences. TCA can be used to estimate CA and its differences with BA, being less than 10 years, are similar to those found in living populations. Differences between CA and BA are due to intra-population variability, which could be the consequence of individual differences in aging. More research is needed to have confidence that under- and overestimations of BA are indicators of aging variability at the level of the individual. © 2017 Wiley Periodicals, Inc.

Identifying a clinical signature of suicidality among patients with mood disorders: A pilot study using a machine learning approach.

PubMed

Passos, Ives Cavalcante; Mwangi, Benson; Cao, Bo; Hamilton, Jane E; Wu, Mon-Ju; Zhang, Xiang Yang; Zunta-Soares, Giovana B; Quevedo, Joao; Kauer-Sant'Anna, Marcia; Kapczinski, Flávio; Soares, Jair C

2016-03-15

A growing body of evidence has put forward clinical risk factors associated with patients with mood disorders that attempt suicide. However, what is not known is how to integrate clinical variables into a clinically useful tool in order to estimate the probability of an individual patient attempting suicide. A total of 144 patients with mood disorders were included. Clinical variables associated with suicide attempts among patients with mood disorders and demographic variables were used to 'train' a machine learning algorithm. The resulting algorithm was utilized in identifying novel or 'unseen' individual subjects as either suicide attempters or non-attempters. Three machine learning algorithms were implemented and evaluated. All algorithms distinguished individual suicide attempters from non-attempters with prediction accuracy ranging between 65% and 72% (p<0.05). In particular, the relevance vector machine (RVM) algorithm correctly predicted 103 out of 144 subjects translating into 72% accuracy (72.1% sensitivity and 71.3% specificity) and an area under the curve of 0.77 (p<0.0001). The most relevant predictor variables in distinguishing attempters from non-attempters included previous hospitalizations for depression, a history of psychosis, cocaine dependence and post-traumatic stress disorder (PTSD) comorbidity. Risk for suicide attempt among patients with mood disorders can be estimated at an individual subject level by incorporating both demographic and clinical variables. Future studies should examine the performance of this model in other populations and its subsequent utility in facilitating selection of interventions to prevent suicide. Copyright © 2015 Elsevier B.V. All rights reserved.

Identifying a clinical signature of suicidality among patients with mood disorders: a pilot study using a machine learning approach

PubMed Central

Passos, Ives Cavalcante; Mwangi, Benson; Cao, Bo; Hamilton, Jane E; Wu, Mon-Ju; Zhang, Xiang Yang; Zunta-Soares, Giovana B.; Quevedo, Joao; Kauer-Sant'Anna, Marcia; Kapczinski, Flávio; Soares, Jair C.

2016-01-01

Objective A growing body of evidence has put forward clinical risk factors associated with patients with mood disorders that attempt suicide. However, what is not known is how to integrate clinical variables into a clinically useful tool in order to estimate the probability of an individual patient attempting suicide. Method A total of 144 patients with mood disorders were included. Clinical variables associated with suicide attempts among patients with mood disorders and demographic variables were used to ‘train’ a machine learning algorithm. The resulting algorithm was utilized in identifying novel or ‘unseen’ individual subjects as either suicide attempters or non-attempters. Three machine learning algorithms were implemented and evaluated. Results All algorithms distinguished individual suicide attempters from non-attempters with prediction accuracy ranging between 65%-72% (p<0.05). In particular, the relevance vector machine (RVM) algorithm correctly predicted 103 out of 144 subjects translating into 72% accuracy (72.1% sensitivity and 71.3% specificity) and an area under the curve of 0.77 (p<0.0001). The most relevant predictor variables in distinguishing attempters from non-attempters included previous hospitalizations for depression, a history of psychosis, cocaine dependence and post-traumatic stress disorder (PTSD) comorbidity. Conclusion Risk for suicide attempt among patients with mood disorders can be estimated at an individual subject level by incorporating both demographic and clinical variables. Future studies should examine the performance of this model in other populations and its subsequent utility in facilitating selection of interventions to prevent suicide. PMID:26773901

Disease-modifying genetic factors in cystic fibrosis.

PubMed

Marson, Fernando A L

2018-05-01

To compile data from the past 10 years regarding the role of modifying genes in cystic fibrosis (CF). CF is a model disease for understanding of the action of modifying genes. Although it is a monogenic (CFTR) autosomal recessive disease, CF presents with wide phenotypic variability. In CF, variability occurs with different intensity among patients by each organ, being organ-specific, resulting from the mutual interaction of environmental and genetic factors, including CFTR mutations and various other genes, most of which are associated with inflammatory processes. In individuals, using precision medicine, gene modification studies have revealed individualized responses to drugs depending on particular CFTR mutations and modifying genes, most of which are alternative ion channels. Studies of modifying genes in CF allow: understanding of clinical variability among patients with the same CFTR genotype; evaluation of precision medicine; understanding of environmental and genetic effects at the organ level; understanding the involvement of genetic variants in inflammatory responses; improvements in genetic counseling; understanding the involvement of genetic variants in inflammatory responses in lung diseases, such as asthma; and understanding the individuality of the person with the disease.

Intraindividual variability of boldness is repeatable across contexts in a wild lizard.

PubMed

Highcock, Laura; Carter, Alecia J

2014-01-01

Animals do not behave in exactly the same way when repeatedly tested in the same context or situation, even once systematic variation, such as habituation, has been controlled for. This unpredictability is called intraindividual variability (IIV) and has been little studied in animals. Here we investigated how IIV in boldness (estimated by flight initiation distances) changed across two seasons--the dry, non-breeding season and the wet, breeding season--in a wild population of the Namibian rock agama, Agama planiceps. We found significant differences in IIV both between individuals and seasons, and IIV was higher in the wet season, suggesting plasticity in IIV. Further, IIV was highly repeatable (r = 0.61) between seasons and we found strong negative correlations between consistent individual differences in flight initiation distances, i.e. their boldness, and individuals' IIVs. We suggest that to understand personality in animals, researchers should generate a personality 'profile' that includes not only the relative level of a trait (i.e. its personality), but also its plasticity and variability under natural conditions.

Individualism, collectivism, and Chinese adolescents' aggression: intracultural variations.

PubMed

Li, Yan; Wang, Mo; Wang, Cixin; Shi, Junqi

2010-01-01

This study examined the relations between cultural values (i.e., individualism and collectivism) and aggression among 460 (234 girls) Chinese adolescents. Conflict level and social status insecurity were examined as potential explaining mechanisms for these relations. The results showed that adolescents' endorsement of collectivism was negatively related to their use of overt and relational aggression as reported by teachers and peers, whereas positive associations were found between the endorsement of individualism and adolescent aggression. Adolescents' conflict level and social status insecurity accounted for a significant part of these associations. Findings of this study demonstrate the importance of examining intracultural variations of cultural values in relation to adolescent aggression as well as the process variables in explaining the relations. (c) 2010 Wiley-Liss, Inc.

The contribution of school-level factors to contraceptive use among adolescents in New York city public high schools

NASA Astrophysics Data System (ADS)

Kaplan, Deborah L.

Every year approximately 17,000 adolescents ages 15-19 become pregnant in New York City. Most of these pregnancies are unintended and only a small percent of adolescents use effective contraception, with wide disparities by race/ethnicity and poverty level. While many studies have identified factors associated with contraceptive use, most research has focused on individual level factors, with little attention to the contribution of the school environment to sexual risk behavior and contraceptive use. This study investigates the effect of school-level factors on contraceptive use among adolescents in NYC public high schools before and after controlling for individual-level factors, and whether this effect varies with race/ethnicity. Using a cross-sectional design, the NYC Youth Risk Behavior Survey (YRBS) individual-level datasets for 2007, 2009 and 2011 were linked to a school-level dataset. Variables were selected based on empirical findings on factors associated with sexual behaviors, including contraceptive use, by adolescents. The analytic sample included all YRBS respondents aged 14 or older who reported having sexual intercourse in the past three months and had complete responses to the YRBS questions on contraceptive use at last sex (N=8,054). The chi square test of significance was used to evaluate significant associations between independent variables and contraceptive use in bivariate analyses; variables with a p value < 0.1 were included in the multivariable analyses. Binary and multinomial logistic regression analyses were conducted to estimate the strength of the associations of school-level factors with contraceptive use among sexually active adolescents. Findings included that use of any contraception and/or hormonal contraception at last sexual intercourse was associated with attending schools with a higher six-year graduation rate, higher percent of students strongly agreeing they were safe in their classrooms, higher percent of teachers at the school for over two years, and having a School-Based Health Center (SBHC) in the building. No known study has examined the contribution of school-level effects to contraceptive use in a dataset linking YRBS and school-level datasets. Implications of research findings are that schools providing a supportive, engaging and safe environment can protect students from sexual risk behaviors and increase contraceptive use among sexually active adolescents.

Assessment of Objectively Measured Physical Activity Levels in Individuals with Intellectual Disabilities with and without Down's Syndrome

PubMed Central

Phillips, Alexander C.; Holland, Anthony J.

2011-01-01

Objective To investigate, using accelerometers, the levels of physical activity being undertaken by individuals with intellectual disabilities with and without Down's syndrome. Methods One hundred and fifty two individuals with intellectual disabilities aged 12–70 years from East and South-East England. Physical activity levels in counts per minute (counts/min), steps per day (steps/day), and minutes of sedentary, light, moderate, vigorous, and moderate to vigorous physical activity (MVPA) measured with a uni-axial accelerometer (Actigraph GT1M) for seven days. Results No individuals with intellectual disabilities met current physical activity recommendations. Males were more active than females. There was a trend for physical activity to decline and sedentary behaviour to increase with age, and for those with more severe levels of intellectual disability to be more sedentary and less physically active, however any relationship was not significant when adjusted for confounding variables. Participants with Down's syndrome engaged in significantly less physical activity than those with intellectual disabilities without Down's syndrome and levels of activity declined significantly with age. Conclusions Individuals with intellectual disabilities, especially those with Down's syndrome may be at risk of developing diseases associated with physical inactivity. There is a need for well-designed, accessible, preventive health promotion strategies and interventions designed to raise the levels of physical activity for individuals with intellectual disabilities. We propose that there are physiological reasons why individuals with Down's syndrome have particularly low levels of physical activity that also decline markedly with age. PMID:22205957

Influence of school-level variables on aggression and associated attitudes of middle school students.

PubMed

Henry, David B; Farrell, Albert D; Schoeny, Michael E; Tolan, Patrick H; Dymnicki, Allison B

2011-10-01

This study sought to understand school-level influences on aggressive behavior and related social cognitive variables. Participants were 5106 middle school students participating in a violence prevention project. Predictors were school-level norms opposing aggression and favoring nonviolence, interpersonal climate (positive student-teacher relationships and positive student-student relationships), and school responsiveness to violence (awareness and reporting of violence and school safety problems). Outcomes were individual-level physical aggression, beliefs supporting aggression, and self-efficacy for nonviolent responses. School norms and both interpersonal climate variables had effects on all three outcomes in theorized directions. Only one of the responsiveness measures, awareness and reporting of violence, had theoretically consistent effects on all outcomes. The other, school safety problems, affected self-efficacy later in middle school. Evidence of gender moderation was generally consistent with greater influence of school-level factors on female adolescents. Discussion focuses on implications in light of previous research and intervention possibilities. Copyright © 2011 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

Organizational Culture and Physician Satisfaction with Dimensions of Group Practice

PubMed Central

Zazzali, James L; Alexander, Jeffrey A; Shortell, Stephen M; Burns, Lawton R

2007-01-01

Research Objective To assess the extent to which the organizational culture of physician group practices is associated with individual physician satisfaction with the managerial and organizational capabilities of the groups. Study Design and Methods Physician surveys from 1997 to 1998 assessing the culture of their medical groups and their satisfaction with six aspects of group practice. Organizational culture was conceptualized using the Competing Values framework, yielding four distinct cultural types. Physician-level data were aggregated to the group level to attain measures of organizational culture. Using hierarchical linear modeling, individual physician satisfaction with six dimensions of group practice was predicted using physician-level variables and group-level variables. Separate models for each of the four cultural types were estimated for each of the six satisfaction measures, yielding a total of 24 models. Sample Studied Fifty-two medical groups affiliated with 12 integrated health systems from across the U.S., involving 1,593 physician respondents (38.3 percent response rate). Larger medical groups and multispecialty groups were over-represented compared with the U.S. as a whole. Principal Findings Our models explain up to 31 percent of the variance in individual physician satisfaction with group practice, with individual organizational culture scales explaining up to 5 percent of the variance. Group-level predictors: group (i.e., participatory) culture was positively associated with satisfaction with staff and human resources, technological sophistication, and price competition. Hierarchical (i.e., bureaucratic) culture was negatively associated with satisfaction with managerial decision making, practice level competitiveness, price competition, and financial capabilities. Rational (i.e., task-oriented) culture was negatively associated with satisfaction with staff and human resources, and price competition. Developmental (i.e., risk-taking) culture was not significantly associated with any of the satisfaction measures. In some of the models, being a single-specialty group (compared with a primary care group) and a group having a higher percent of male physicians were positively associated with satisfaction with financial capabilities. Physician-level predictors: individual physicians' ratings of organizational culture were significantly related to many of the satisfaction measures. In general, older physicians were more satisfied than younger physicians with many of the satisfaction measures. Male physicians were less satisfied with data capabilities. Primary care physicians (versus specialists) were less satisfied with price competition. Conclusion Some dimensions of physician organizational culture are significantly associated with various aspects of individual physician satisfaction with group practice. PMID:17489908

Seasonality of tuberculosis in Israel, 2001-2011.

PubMed

Margalit, I; Block, C; Mor, Z

2016-12-01

Several studies have suggested that the incidence of tuberculosis (TB) varies with the seasons. To determine the seasonality of TB in Israel and to explore possible associations with climatic variables. Laboratory-confirmed TB cases reported between 2001 and 2011 in individuals resident in Israel for at least 1 year before diagnosis were included in the study. Climatic variables included average temperature and average ultraviolet radiation. The mean serum 25-hydroxyvitamin D level of the population was also recorded. Of all 2653 TB cases, incidence peaked during spring (n = 712) and reached its nadir during the fall (n = 577), with a case proportion amplitude (CPA) of 5.1% (P = 0.036). Individuals born in the Horn of Africa exhibited a CPA of 9.5% (P = 0.077). Mean population 25-hydroxyvitamin D level was significantly correlated with the seasonal pattern of the disease. Southern Israel had the highest global radiation and, counter-instinctively, the highest TB incidence. TB exhibited a seasonal tendency in Israel, with the spring peak/fall nadir pattern found elsewhere. Vitamin D is suspected to be an explanatory variable for this seasonal phenomenon. The finding that the highest incidence is in the area receiving the highest global radiation suggests population-related vulnerability to vitamin D deficiency.

Collective hormonal profiles predict group performance.

PubMed

Akinola, Modupe; Page-Gould, Elizabeth; Mehta, Pranjal H; Lu, Jackson G

2016-08-30

Prior research has shown that an individual's hormonal profile can influence the individual's social standing within a group. We introduce a different construct-a collective hormonal profile-which describes a group's hormonal make-up. We test whether a group's collective hormonal profile is related to its performance. Analysis of 370 individuals randomly assigned to work in 74 groups of three to six individuals revealed that group-level concentrations of testosterone and cortisol interact to predict a group's standing across groups. Groups with a collective hormonal profile characterized by high testosterone and low cortisol exhibited the highest performance. These collective hormonal level results remained reliable when controlling for personality traits and group-level variability in hormones. These findings support the hypothesis that groups with a biological propensity toward status pursuit (high testosterone) coupled with reduced stress-axis activity (low cortisol) engage in profit-maximizing decision-making. The current work extends the dual-hormone hypothesis to the collective level and provides a neurobiological perspective on the factors that determine who rises to the top across, not just within, social hierarchies.

Psychophysiological Correlates of Generalized Anxiety Disorder with or without Comorbid Depression

PubMed Central

Hofmann, Stefan G.; Schulz, Stefan M.; Heering, Sanna; Muench, Frederick; Bufka, Lynn F.

2010-01-01

It remains uncertain whether generalized anxiety disorder (GAD) and major depressive disorder (MDD) represent two separate diagnostic entities. The goal of this study was to examine whether comorbid MDD distinguishes individuals with GAD on a psychophysiological level during an experimentally-induced worrying procedure. Participants included 39 individuals with GAD, 14 of whom met criteria for MDD. During the experimental procedure, participants were asked to worry or relax after an initial baseline phase while measuring their heart rate, high frequency heart rate variability (HF-HRV), skin conductance level, and subjective level of anxiety. The two groups did not differ in their subjective anxiety, heart rate response, and skin conductance levels. However, participants with comorbid MDD had greater HF-HRV values throughout the experiment than did those without MDD. At baseline, HF-HRV was significantly correlated with a self-report measure of depression. These results suggest that individuals with comorbid GAD and MDD can be distinguished based on HF-HRV from individuals with GAD but without MDD. These results support the distinction between GAD and MDD. PMID:20093149

Health behavior change models for HIV prevention and AIDS care: practical recommendations for a multi-level approach.

PubMed

Kaufman, Michelle R; Cornish, Flora; Zimmerman, Rick S; Johnson, Blair T

2014-08-15

Despite increasing recent emphasis on the social and structural determinants of HIV-related behavior, empirical research and interventions lag behind, partly because of the complexity of social-structural approaches. This article provides a comprehensive and practical review of the diverse literature on multi-level approaches to HIV-related behavior change in the interest of contributing to the ongoing shift to more holistic theory, research, and practice. It has the following specific aims: (1) to provide a comprehensive list of relevant variables/factors related to behavior change at all points on the individual-structural spectrum, (2) to map out and compare the characteristics of important recent multi-level models, (3) to reflect on the challenges of operating with such complex theoretical tools, and (4) to identify next steps and make actionable recommendations. Using a multi-level approach implies incorporating increasing numbers of variables and increasingly context-specific mechanisms, overall producing greater intricacies. We conclude with recommendations on how best to respond to this complexity, which include: using formative research and interdisciplinary collaboration to select the most appropriate levels and variables in a given context; measuring social and institutional variables at the appropriate level to ensure meaningful assessments of multiple levels are made; and conceptualizing intervention and research with reference to theoretical models and mechanisms to facilitate transferability, sustainability, and scalability.

Understanding the link between childhood maltreatment and violent delinquency: what do schools have to add?

PubMed

Crooks, Claire V; Scott, Katreena L; Wolfe, David A; Chiodo, Debbie; Killip, Steve

2007-08-01

Child maltreatment constitutes significant risk for adolescent delinquency. Although an ecological model has been proposed to explain this relationship, most studies focus on individual risk factors. Prospective data from 1,788 students attending 23 schools were used to examine the additive influence of childhood maltreatment, individual-level risk factors, and school-level variables assessed at the beginning of Grade 9 on delinquency 4 to 6 months later. Individual-level results indicated that being male, experiencing childhood maltreatment, and poor parental nurturing were predictors of violent delinquency. School climate also played a significant role: Given the same individual risk profile, a student attending a school that was perceived by students as safe was less likely to engage in violent delinquency than was a student attending a school perceived to be unsafe. Moreover, the impact of childhood maltreatment on risk for engaging in violent delinquency was somewhat mitigated by schools' participation in a comprehensive violence prevention program.

Exploratory factor analysis of pathway copy number data with an application towards the integration with gene expression data.

PubMed

van Wieringen, Wessel N; van de Wiel, Mark A

2011-05-01

Realizing that genes often operate together, studies into the molecular biology of cancer shift focus from individual genes to pathways. In order to understand the regulatory mechanisms of a pathway, one must study its genes at all molecular levels. To facilitate such study at the genomic level, we developed exploratory factor analysis for the characterization of the variability of a pathway's copy number data. A latent variable model that describes the call probability data of a pathway is introduced and fitted with an EM algorithm. In two breast cancer data sets, it is shown that the first two latent variables of GO nodes, which inherit a clear interpretation from the call probabilities, are often related to the proportion of aberrations and a contrast of the probabilities of a loss and of a gain. Linking the latent variables to the node's gene expression data suggests that they capture the "global" effect of genomic aberrations on these transcript levels. In all, the proposed method provides an possibly insightful characterization of pathway copy number data, which may be fruitfully exploited to study the interaction between the pathway's DNA copy number aberrations and data from other molecular levels like gene expression.

Variability of High-Resolution Sea Surface Heights on a Broad, Shallow Continental Shelf

NASA Astrophysics Data System (ADS)

Crout, R. L.; Rice, A. E.

2017-12-01

Recent satellite altimeter technologies and processing methodologies are allowing investigation of the dynamics of the continental shelf as never before. The region seaward of 20 km from the coast is a region where winds, tides, currents, river discharge, and bathymetry interact. All of these are important parameters to understand when applying coastal altimetry to coastal sea level monitoring. Processing of 8 years (July 2008 to July 2016) of Jason-2 altimeter 20 Hz data from the L2 AVISO-PISTACH experimental products yields nearly 300 crossings of the broad continental shelf to the southeast of Delaware Bay from Cape May, NJ. Removal of a mean surface yields individual crossings that, plotted together, form an envelope that shows high water level variability near the coast. Water level changes near the coast begin at a hinge point that occurs approximately 50 km from shore in less than 30 meters of water. Comparison of individual Jason-2 passes with regional weather patterns, cold front passages, local winds, tides, surface currents, river discharge, and regional oceanography provides information regarding the forcing factors for these regional water levels. The water levels farther than 20 km from shore show similar patterns to the low pass filtered tide data at Cape May, NJ and respond primarily to regional forcing.

Socioeconomic status and exposure to outdoor NO2 and benzene in the Asturias INMA birth cohort, Spain

PubMed Central

Fernández-Somoano, Ana; Tardon, Adonina

2014-01-01

Background It is commonly assumed that low socioeconomic levels are associated with greater exposure to pollution, but this is not necessarily valid. Our goal was to examine how individual socioeconomic characteristics are associated with exposure levels in a Spanish region included in the INfancia y Medio Ambiente (INMA) cohort. Methods The study population comprised 430 pregnant women from the Asturias INMA cohort. Air pollution exposure was estimated using land-use regression techniques. Information about the participants’ lifestyle and socioeconomic variables was collected through questionnaires. In multivariate analysis, the levels of NO2 and benzene assigned to each woman were considered as dependent variables. Other variables included in the models were residential zone, age, education, parity, smoking, season, working status during pregnancy and social class. Results The average NO2 level was 23.60 (SD=6.50) μg/m3. For benzene, the mean value was 2.31 (SD=1.32) μg/m3. We found no association of any pollutant with education. We observed an association between social class and benzene levels. Social classes I and II had the highest levels. The analysed socioeconomic and lifestyle variables accounted for little variability in air pollution in the models; this variability was explained mainly by residential zone (adjusted R2: 0.27 for NO2; 0.09 for benzene). Conclusions Education and social class were not clearly associated with pollution. Administrations should monitor the environment of residential areas regardless of the socioeconomic level, and they should increase the distances between housing and polluting sources to prevent settlements at distances that are harmful to health. PMID:23999377

Clinical periodontal variables in patients with and without dementia-a systematic review and meta-analysis.

PubMed

Maldonado, Alejandra; Laugisch, Oliver; Bürgin, Walter; Sculean, Anton; Eick, Sigrun

2018-06-22

Considering the increasing number of elderly people, dementia has gained an important role in today's society. Although the contributing factors for dementia have not been fully understood, chronic periodontitis (CP) seems to have a possible link to dementia. To conduct a systematic review including meta-analysis in order to assess potential differences in clinical periodontal variables between patients with dementia and non-demented individuals. The following focused question was evaluated: is periodontitis associated with dementia? Electronic searches in two databases, MEDLINE and EMBASE, were conducted. Meta-analysis was performed with the collected data in order to find a statistically significant difference in clinical periodontal variables between the group of dementia and the cognitive normal controls. Forty-two articles remained for full text reading. Finally, seven articles met the inclusion criteria and only five studies provided data suitable for meta-analysis. Periodontal probing depth (PPD), bleeding on probing (BOP), gingival bleeding index (GBI), clinical attachment level (CAL), and plaque index (PI) were included as periodontal variables in the meta-analysis. Each variable revealed a statistically significant difference between the groups. In an attempt to reveal an overall difference between the periodontal variables in dementia patients and non-demented individuals, the chosen variables were transformed into units that resulted in a statistically significant overall difference (p < 0.00001). The current findings indicate that compared to systemically healthy individuals, demented patients show significantly worse clinical periodontal variables. However, further epidemiological studies including a high numbers of participants, the use of exact definitions both for dementia and chronic periodontitis and adjusted for cofounders is warranted. These findings appear to support the putative link between CP and dementia. Consequently, the need for periodontal screening and treatment of elderly demented people should be emphasized.

Access to health care and community social capital.

PubMed

Hendryx, Michael S; Ahern, Melissa M; Lovrich, Nicholas P; McCurdy, Arthur H

2002-02-01

To test the hypothesis that variation in reported access to health care is positively related to the level of social capital present in a community. The 1996 Household Survey of the Community Tracking Study, drawn from 22 metropolitan statistical areas across the United States (n = 19,672). Additional data for the 22 communities are from a 1996 multicity broadcast media marketing database, including key social capital indicators, the 1997 National Profile of Local Health Departments survey, and Interstudy, American Hospital Association, and American Medical Association sources. The design is cross-sectional. Self-reported access to care problems is the dependent variable. Independent variables include individual sociodemographic variables, community-level health sector variables, and social capital variables. Data are merged from the various sources and weighted to be population representative and are analyzed using hierarchical categorical modeling. Persons who live in metropolitan statistical areas featuring higher levels of social capital report fewer problems accessing health care. A higher HMO penetration rate in a metropolitan statistical area was also associated with fewer access problems. Other health sector variables were not related to health care access. The results observed for 22 major U.S. cities are consistent with the hypothesis that community social capital enables better access to care, perhaps through improving community accountability mechanisms.

Variability in adherence to clinical practice guidelines and recommendations in COPD outpatients: a multi-level, cross-sectional analysis of the EPOCONSUL study.

PubMed

Calle Rubio, Myriam; López-Campos, José Luis; Soler-Cataluña, Juan J; Alcázar Navarrete, Bernardino; Soriano, Joan B; Rodríguez González-Moro, José Miguel; Fuentes Ferrer, Manuel E; Rodríguez Hermosa, Juan Luis

2017-12-02

Clinical audits have reported considerable variability in COPD medical care and frequent inconsistencies with recommendations. The objectives of this study were to identify factors associated with a better adherence to clinical practice guidelines and to explore determinants of this variability at the the hospital level. EPOCONSUL is a Spanish nationwide clinical audit that evaluates the outpatient management of COPD. Multilevel logistic regression with two levels was performed to assess the relationships between individual and disease-related factors, as well as hospital characteristics. A total of 4508 clinical records of COPD patients from 59 Spanish hospitals were evaluated. High variability was observed among hospitals in terms of medical care. Some of the patient's characteristics (airflow obstruction, degree of dyspnea, exacerbation risk, presence of comorbidities), the hospital factors (size and respiratory nurses available) and treatment at a specialized COPD outpatient clinic were identified as factors associated with a better adherence to recommendations, although this only explains a small proportion of the total variance. To be treated at a specialized COPD outpatient clinic and some intrinsic patient characteristics were factors associated with a better adherence to guideline recommendations, although these variables were only explaining part of the high variability observed among hospitals in terms of COPD medical care.

Hydrogen sulfide and particle matter levels associated with increased dispensing of anti-asthma drugs in Iceland's capital.

PubMed

Carlsen, Hanne Krage; Zoëga, Helga; Valdimarsdóttir, Unnur; Gíslason, Thórarinn; Hrafnkelsson, Birgir

2012-02-01

Air pollutants in Iceland's capital area include hydrogen sulfide (H2S) emissions from geothermal power plants, particle pollution (PM10) and traffic-related pollutants. Respiratory health effects of exposure to PM and traffic pollutants are well documented, yet this is one of the first studies to investigate short-term health effects of ambient H2S exposure. The aim of this study was to investigate the associations between daily ambient levels of H2S, PM10, nitrogen dioxide (NO2) and ozone (O3), and the use of drugs for obstructive pulmonary diseases in adults in Iceland's capital area. The study period was 8 March 2006 to 31 December 2009. We used log-linear Poisson generalized additive regression models with cubic splines to estimate relative risks of individually dispensed drugs by air pollution levels. A three-day moving average of the exposure variables gave the best fit to the data. Final models included significant covariates adjusting for climate and influenza epidemics, as well as time-dependent variables. The three-day moving average of H2S and PM10 levels were positively associated with the number of individuals who were dispensed drugs at lag 3-5, corresponding to a 2.0% (95% confidence interval [CI] 0.4, 3.6) and 0.9% (95% CI 0.1, 1.8) per 10 μg/m3 pollutant concentration increase, respectively. Our findings indicated that intermittent increases in levels of particle matter from traffic and natural sources and ambient H2S levels were weakly associated with increased dispensing of drugs for obstructive pulmonary disease in Iceland's capital area. These weak associations could be confounded by unevaluated variables hence further studies are needed. Copyright © 2012 Elsevier Inc. All rights reserved.

Unity and diversity of executive functions: Individual differences as a window on cognitive structure.

PubMed

Friedman, Naomi P; Miyake, Akira

2017-01-01

Executive functions (EFs) are high-level cognitive processes, often associated with the frontal lobes, that control lower level processes in the service of goal-directed behavior. They include abilities such as response inhibition, interference control, working memory updating, and set shifting. EFs show a general pattern of shared but distinct functions, a pattern described as "unity and diversity". We review studies of EF unity and diversity at the behavioral and genetic levels, focusing on studies of normal individual differences and what they reveal about the functional organization of these cognitive abilities. In particular, we review evidence that across multiple ages and populations, commonly studied EFs (a) are robustly correlated but separable when measured with latent variables; (b) are not the same as general intelligence or g; (c) are highly heritable at the latent level and seemingly also highly polygenic; and (d) activate both common and specific neural areas and can be linked to individual differences in neural activation, volume, and connectivity. We highlight how considering individual differences at the behavioral and neural levels can add considerable insight to the investigation of the functional organization of the brain, and conclude with some key points about individual differences to consider when interpreting neuropsychological patterns of dissociation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Baseline Chromatin Modification Levels May Predict ...

EPA Pesticide Factsheets

Traditional toxicological paradigms have relied on factors such as age, genotype, and disease status to explain variability in responsiveness to toxicant exposure; however, these are neither sufficient to faithfully identify differentially responsive individuals nor are they modifiable factors that can be leveraged to mitigate the exposure effects. Unlike these factors, the epigenome is dynamic and shaped by an individual's environment. We sought to determine whether baseline levels of specific chromatin modifications correlated with the interindividual variability in their ozone (03)-mediated induction in an air-liquid interface model using primary human bronchial epithelial cells from a panel of 11 donors. We characterized the relationship between the baseline abundance of 6 epigenetic markers with established roles as key regulators of gene expression-histone H3 lysine 4 trimethylation (H3K4me3), H3K27 acetylation (H3K27ac), pan­acetyl H4 (H4ac), histone H3K27 di/trimethylation (H3K27me2/3), unmodified H3, and5-hydroxymethylcytosine (5-hmC)-and the variability in the 03-induced expression of IL-8, IL-6, COX2, and HMOX1. Baseline levels of H3K4me3, H3K27me2/3, and 5-hmC, but not H3K27ac, H4ac, and total H3, correlated with the interindividual variability in 03-mediated induction of HMOX1 and COX2. In contrast, none of the chromatin modifications that we examined correlated with the induction of IL-8 and IL-6. From these findings, we propose an "epigenetic see

Reporting of methodological features in observational studies of pre-harvest food safety.

PubMed

Sargeant, Jan M; O'Connor, Annette M; Renter, David G; Kelton, David F; Snedeker, Kate; Wisener, Lee V; Leonard, Erin K; Guthrie, Alessia D; Faires, Meredith

2011-02-01

Observational studies in pre-harvest food safety may be useful for identifying risk factors and for evaluating potential mitigation strategies to reduce foodborne pathogens. However, there are no structured reporting guidelines for these types of study designs in livestock species. Our objective was to evaluate the reporting of observational studies in the pre-harvest food safety literature using guidelines modified from the human healthcare literature. We identified 100 pre-harvest food safety studies published between 1999 and 2009. Each study was evaluated independently by two reviewers using a structured checklist. Of the 38 studies that explicitly stated the observational study design, 27 were described as cross-sectional studies, eight as case-control studies, and three as cohort studies. Study features reported in over 75% of the selected studies included: description of the geographic location of the studies, definitions and sources of data for outcomes, organizational level and source of data for independent variables, description of statistical methods and results, number of herds enrolled in the study and included in the analysis, and sources of study funding. However, other features were not consistently reported, including details related to eligibility criteria for groups (such as barn, room, or pen) and individuals, numbers of groups and individuals included in various stages of the study, identification of primary outcomes, the distinction between putative risk factors and confounding variables, the identification of a primary exposure variable, the referent level for evaluation of categorical variable associations, methods of controlling confounding variables and missing variables, model fit, details of subset analysis, demographic information at the sampling unit level, and generalizability of the study results. Improvement in reporting of observational studies of pre-harvest food safety will aid research readers and reviewers in interpreting and evaluating the results of such studies. Copyright © 2010 Elsevier B.V. All rights reserved.

Effects of wheelchair sports on respiratory muscle strength and thoracic mobility of individuals with spinal cord injury.

PubMed

Moreno, Marlene Aparecida; Zamunér, Antonio Roberto; Paris, Juliana Viana; Teodori, Rosana Macher; Barros, Ricardo M L

2012-06-01

The aim of this study was to evaluate the effects of wheelchair sports on respiratory muscle strength and the thoracic mobility of individuals with spinal cord injury. Thirty male subjects with chronic spinal cord injury (American Spinal Injury Association Impairment Scale grade A) took part in the study and were divided into four groups: sedentary subjects with quadriplegia (S-QUAD, n = 7), wheelchair rugby athletes with quadriplegia (A-QUAD, n = 8), sedentary subjects with paraplegia (S-PARA, n = 6), and wheelchair basketball athletes with paraplegia (A-PARA, n = 9). The main outcome measures were maximal inspiratory and expiratory pressure and the respiratory coefficients at the axillary and xiphoid levels. A-QUAD group presented values significantly higher for all respiratory variables studied compared with the S-QUAD group. No significant differences in any of the respiratory variables were observed between S-PARA and A-PARA groups. There was a negative correlation between spinal cord injury level and respiratory variables for the S-QUAD and S-PARA groups. There were positive correlations in the A-QUAD group between time of training and maximal inspiratory pressure (adjusted R = 0.84; P = 0.001) and respiratory coefficients at the axillary level (adjusted R = 0.80; P = 0.002). Physical training seems to have a positive influence on respiratory muscle strength and thoracic mobility, especially in subjects with quadriplegia.

Community Influences on Married Women's Safer Sex Negotiation Attitudes in Bangladesh: A Multilevel Analysis.

PubMed

Jesmin, Syeda S; Cready, Cynthia M

2016-02-01

The influence of disadvantaged or deprived community on individuals' health risk-behaviors is increasingly being documented in a growing body of literature. However, little is known about the effects of community characteristics on women's sexual attitudes and behaviors. To examine community effects on married women's safer sex negotiation attitudes, we analyzed cross-sectional data from the 2011 Bangladesh Demographic and Health Surveys on a sample of 15,134 married women in 600 communities. We estimated two multilevel logistic regression models. Model 1, which included only individual-level variables, showed that women's autonomy/empowerment, age, and HIV knowledge had significant associations with their safer sex negotiation attitudes. We did not find any socioeconomic status gradient in safer sex negotiation attitudes at the individual level. Adding community-level variables in Model 2 significantly improved the fit of the model. Strikingly, we found that higher community-level poverty was associated with greater positive safer sex negotiation attitudes. Prevailing gender norms and overall women's empowerment in the community also had significant effects. While research on community influences calls for focusing on disadvantaged communities, our research highlights the importance of not underestimating the challenges that married women in economically privileged communities may face in negotiating safer sex. To have sufficient and equitable impact on married women's sexual and reproductive health, sexual and reproductive health promotion policies and programs need to be directed to women in wealthier communities as well.

Artifact removal in the context of group ICA: a comparison of single-subject and group approaches

PubMed Central

Du, Yuhui; Allen, Elena A.; He, Hao; Sui, Jing; Wu, Lei; Calhoun, Vince D.

2018-01-01

Independent component analysis (ICA) has been widely applied to identify intrinsic brain networks from fMRI data. Group ICA computes group-level components from all data and subsequently estimates individual-level components to recapture inter-subject variability. However, the best approach to handle artifacts, which may vary widely among subjects, is not yet clear. In this work, we study and compare two ICA approaches for artifacts removal. One approach, recommended in recent work by the Human Connectome Project, first performs ICA on individual subject data to remove artifacts, and then applies a group ICA on the cleaned data from all subjects. We refer to this approach as Individual ICA based artifacts Removal Plus Group ICA (IRPG). A second proposed approach, called Group Information Guided ICA (GIG-ICA), performs ICA on group data, then removes the group-level artifact components, and finally performs subject-specific ICAs using the group-level non-artifact components as spatial references. We used simulations to evaluate the two approaches with respect to the effects of data quality, data quantity, variable number of sources among subjects, and spatially unique artifacts. Resting-state test-retest datasets were also employed to investigate the reliability of functional networks. Results from simulations demonstrate GIG-ICA has greater performance compared to IRPG, even in the case when single-subject artifacts removal is perfect and when individual subjects have spatially unique artifacts. Experiments using test-retest data suggest that GIG-ICA provides more reliable functional networks. Based on high estimation accuracy, ease of implementation, and high reliability of functional networks, we find GIG-ICA to be a promising approach. PMID:26859308

Pharmacodynamics of Voriconazole in Children: Further Steps along the Path to True Individualized Therapy

PubMed Central

Huurneman, Luc J.; Neely, Michael; Veringa, Anette; Docobo Pérez, Fernando; Ramos-Martin, Virginia; Tissing, Wim J.; Alffenaar, Jan-Willem C.

2016-01-01

Voriconazole is the agent of choice for the treatment of invasive aspergillosis in children at least 2 years of age. The galactomannan index is a routinely used diagnostic marker for invasive aspergillosis and can be useful for following the clinical response to antifungal treatment. The aim of this study was to develop a pharmacokinetic-pharmacodynamic (PK-PD) mathematical model that links the pharmacokinetics of voriconazole with the galactomannan readout in children. Twelve children receiving voriconazole for treatment of proven, probable, and possible invasive fungal infections were studied. A previously published population PK model was used as the Bayesian prior. The PK-PD model was used to estimate the average area under the concentration-time curve (AUC) in each patient and the resultant galactomannan-time profile. The relationship between the ratio of the AUC to the concentration of voriconazole that induced half maximal killing (AUC/EC50) and the terminal galactomannan level was determined. The voriconazole concentration-time and galactomannan-time profiles were both highly variable. Despite this variability, the fit of the PK-PD model was good, enabling both the pharmacokinetics and pharmacodynamics to be described in individual children. (AUC/EC50)/15.4 predicted terminal galactomannan (P = 0.003), and a ratio of >6 suggested a lower terminal galactomannan level (P = 0.07). The construction of linked PK-PD models is the first step in developing control software that enables not only individualized voriconazole dosages but also individualized concentration targets to achieve suppression of galactomannan levels in a timely and optimally precise manner. Controlling galactomannan levels is a first critical step to maximizing clinical response and survival. PMID:26833158

Peritraumatic Reaction Courses During War in Individuals With Serious Mental Illness: Gender, Mental Health Status, and Exposure.

PubMed

Gelkopf, Marc; Lapid Pickman, Liron; Grinapol, Shulamit; Werbeloff, Nomi; Carlson, Eve B; Greene, Talya

2017-01-01

We assessed in vivo symptom courses of early psychological responses during war and investigated the influence of exposure, gender, and a prior diagnosis of severe mental illness (SMI). Participants were 181 highly exposed individuals from the general population and community psychiatric rehabilitation centers. A 30-day twice-daily Internet-smartphone-based intensive assessment two weeks into the 2014 Israel-Gaza war estimated peritraumatic symptom clusters, sense of threat, negative emotions and cognitions, and siren exposure during two periods that varied in exposure level. Piecewise growth curve modeling procedures were performed. We found different courses for most variables, gender, and SMI status. Women were more reactive two weeks into the war but reduced their reactivity level at a faster pace than males, reaching lower symptom levels one month later. Women's courses were characterized by arousal, negative emotionality, sense of threat, and reactivity to siren exposure. No-SMI men had a stable course followed by a significant reduction in arousal, negative emotions, avoidance, and perceived threat during a "return to routine" lower-level intensity period of the war. Individuals with SMI had higher reactivity levels at study onset; but while women with SMI improved over time, men with SMI worsened. SMI reactivity was characterized by negative cognitions, intrusions, and avoidance. Early reactions during prolonged exposure to war are variable, dynamic, and affected by exposure context. Symptoms, emotions, and cognitions develop differentially over time and are affected by gender and mental health status. The identification of various early stress courses should inform primary intervention strategies.

Magnitude and Temporal Variability of Inter-stimulus EEG Modulate the Linear Relationship Between Laser-Evoked Potentials and Fast-Pain Perception

PubMed Central

Li, Linling; Huang, Gan; Lin, Qianqian; Liu, Jia; Zhang, Shengli; Zhang, Zhiguo

2018-01-01

The level of pain perception is correlated with the magnitude of pain-evoked brain responses, such as laser-evoked potentials (LEP), across trials. The positive LEP-pain relationship lays the foundation for pain prediction based on single-trial LEP, but cross-individual pain prediction does not have a good performance because the LEP-pain relationship exhibits substantial cross-individual difference. In this study, we aim to explain the cross-individual difference in the LEP-pain relationship using inter-stimulus EEG (isEEG) features. The isEEG features (root mean square as magnitude and mean square successive difference as temporal variability) were estimated from isEEG data (at full band and five frequency bands) recorded between painful stimuli. A linear model was fitted to investigate the relationship between pain ratings and LEP response for fast-pain trials on a trial-by-trial basis. Then the correlation between isEEG features and the parameters of LEP-pain model (slope and intercept) was evaluated. We found that the magnitude and temporal variability of isEEG could modulate the parameters of an individual's linear LEP-pain model for fast-pain trials. Based on this, we further developed a new individualized fast-pain prediction scheme, which only used training individuals with similar isEEG features as the test individual to train the fast-pain prediction model, and obtained improved accuracy in cross-individual fast-pain prediction. The findings could help elucidate the neural mechanism of cross-individual difference in pain experience and the proposed fast-pain prediction scheme could be potentially used as a practical and feasible pain prediction method in clinical practice. PMID:29904336

Investigating the Effect of Recruitment Variability on Length-Based Recruitment Indices for Antarctic Krill Using an Individual-Based Population Dynamics Model

PubMed Central

Thanassekos, Stéphane; Cox, Martin J.; Reid, Keith

2014-01-01

Antarctic krill (Euphausia superba; herein krill) is monitored as part of an on-going fisheries observer program that collects length-frequency data. A krill feedback management programme is currently being developed, and as part of this development, the utility of data-derived indices describing population level processes is being assessed. To date, however, little work has been carried out on the selection of optimum recruitment indices and it has not been possible to assess the performance of length-based recruitment indices across a range of recruitment variability. Neither has there been an assessment of uncertainty in the relationship between an index and the actual level of recruitment. Thus, until now, it has not been possible to take into account recruitment index uncertainty in krill stock management or when investigating relationships between recruitment and environmental drivers. Using length-frequency samples from a simulated population – where recruitment is known – the performance of six potential length-based recruitment indices is assessed, by exploring the index-to-recruitment relationship under increasing levels of recruitment variability (from ±10% to ±100% around a mean annual recruitment). The annual minimum of the proportion of individuals smaller than 40 mm (F40 min, %) was selected because it had the most robust index-to-recruitment relationship across differing levels of recruitment variability. The relationship was curvilinear and best described by a power law. Model uncertainty was described using the 95% prediction intervals, which were used to calculate coverage probabilities and assess model performance. Despite being the optimum recruitment index, the performance of F40 min degraded under high (>50%) recruitment variability. Due to the persistence of cohorts in the population over several years, the inclusion of F40 min values from preceding years in the relationship used to estimate recruitment in a given year improved its accuracy (mean bias reduction of 8.3% when including three F40 min values under a recruitment variability of 60%). PMID:25470296

Daytime variation in ambient temperature affects skin temperatures and blood pressure: Ambulatory winter/summer comparison in healthy young women.

PubMed

Martinez-Nicolas, Antonio; Meyer, Martin; Hunkler, Stefan; Madrid, Juan Antonio; Rol, Maria Angeles; Meyer, Andrea H; Schötzau, Andy; Orgül, Selim; Kräuchi, Kurt

2015-10-01

It is widely accepted that cold exposure increases peripheral vascular resistance and arterial blood pressure (BP) and, hence, increases cardiovascular risk primarily in the elderly. However, there is a lack of concomitantly longitudinal recordings at personal level of environmental temperature (PET) and cardiophysiological variables together with skin temperatures (STs, the “interface-variable” between the body core and ambient temperature). To investigate the intra-individual temporal relationships between PET, STs and BP 60 healthy young women (52 completed the entire study) were prospectively studied in a winter/summer design for 26 h under real life conditions. The main hypothesis was tested whether distal ST (Tdist)mediates the effect of PET-changes on mean arterial BP (MAP). Diurnal profiles of cardiophysiological variables (including BP), STs and PET were ambulatory recorded. Daytime variations between 0930 and 2030 h were analyzed in detail by intra-individual longitudinal path analysis. Additionally, time segments before, during and after outdoor exposure were separately analyzed. In both seasons short-term variations in PET were positively associated with short-term changes in Tdist (not proximal ST, Tprox) and negatively with those in MAP. However, long-term seasonal differences in daytime mean levels were observed in STs but not in BP leading to non-significant inter-individual correlation between STs and BP. Additionally, higher individual body mass index (BMI) was significantly associated with lower daytime mean levels of Tprox and higher MAP suggesting Tprox as potential mediator variable for the association of BMI with MAP. In healthy young women the thermoregulatory and BP-regulatory systems are closely linked with respect to short-term, but not long-term changes in PET. One hypothetical explanation could serve recent findings that thermogenesis in brown adipose tissue is activated in a cool environment, which could be responsible for the counter-regulation of cold induced increase of BP in winter leading to no seasonal differences in MAP. Our findings suggest that the assessment of diurnal patterns of STs and PET, in addition to the conventional ambulatory BP monitoring, might improve individual cardiovascular risk prediction.

Autonomy dimensions and care seeking for delivery in Zambia; the prevailing importance of cluster-level measurement.

PubMed

Gabrysch, Sabine; McMahon, Shannon A; Siling, Katja; Kenward, Michael G; Campbell, Oona M R

2016-03-02

It is widely held that decisions whether or when to attend health facilities for childbirth are not only influenced by risk awareness and household wealth, but also by factors such as autonomy or a woman's ability to act upon her own preferences. How autonomy should be constructed and measured - namely, as an individual or cluster-level variable - has been less examined. We drew on household survey data from Zambia to study the effect of several autonomy dimensions (financial, relationship, freedom of movement, health care seeking and violence) on place of delivery for 3200 births across 203 rural clusters (villages). In multilevel logistic regression, two autonomy dimensions (relationship and health care seeking) were strongly associated with facility delivery when measured at the cluster level (OR 1.27 and 1.57, respectively), though not at the individual level. This suggests that power relations and gender norms at the community level may override an individual woman's autonomy, and cluster-level measurement may prove critical to understanding the interplay between autonomy and care seeking in this and similar contexts.

Autonomy dimensions and care seeking for delivery in Zambia; the prevailing importance of cluster-level measurement

PubMed Central

Gabrysch, Sabine; McMahon, Shannon A.; Siling, Katja; Kenward, Michael G.; Campbell, Oona M. R.

2016-01-01

It is widely held that decisions whether or when to attend health facilities for childbirth are not only influenced by risk awareness and household wealth, but also by factors such as autonomy or a woman’s ability to act upon her own preferences. How autonomy should be constructed and measured – namely, as an individual or cluster-level variable – has been less examined. We drew on household survey data from Zambia to study the effect of several autonomy dimensions (financial, relationship, freedom of movement, health care seeking and violence) on place of delivery for 3200 births across 203 rural clusters (villages). In multilevel logistic regression, two autonomy dimensions (relationship and health care seeking) were strongly associated with facility delivery when measured at the cluster level (OR 1.27 and 1.57, respectively), though not at the individual level. This suggests that power relations and gender norms at the community level may override an individual woman’s autonomy, and cluster-level measurement may prove critical to understanding the interplay between autonomy and care seeking in this and similar contexts. PMID:26931301

Interrater Agreement on the Visual Analysis of Individual Tiers and Functional Relations in Multiple Baseline Designs.

PubMed

Wolfe, Katie; Seaman, Michael A; Drasgow, Erik

2016-11-01

Previous research on visual analysis has reported low levels of interrater agreement. However, many of these studies have methodological limitations (e.g., use of AB designs, undefined judgment task) that may have negatively influenced agreement. Our primary purpose was to evaluate whether agreement would be higher than previously reported if we addressed these weaknesses. Our secondary purposes were to investigate agreement at the tier level (i.e., the AB comparison) and at the functional relation level in multiple baseline designs and to examine the relationship between raters' decisions at each of these levels. We asked experts (N = 52) to make judgments about changes in the dependent variable in individual tiers and about the presence of an overall functional relation in 31 multiple baseline graphs. Our results indicate that interrater agreement was just at or just below minimally adequate levels for both types of decisions and that agreement at the individual tier level often resulted in agreement about the overall functional relation. We report additional findings and discuss implications for practice and future research. © The Author(s) 2016.

Physiological indices of stress in wild and captive garter snakes: correlations, repeatability, and ecological variation.

PubMed

Sparkman, Amanda M; Bronikowski, Anne M; Williams, Shelby; Parsai, Shikha; Manhart, Whitney; Palacios, Maria G

2014-08-01

Glucocorticoids and leukocyte ratios have become the most widespread variables employed to test hypotheses regarding physiological stress in wild and captive vertebrates. Little is known, however, regarding how these two indices of stress covary in response to stressors, their repeatability within individuals, and differences in response time upon capture. Furthermore, few studies compare stress indices between captive and wild populations, to assess potential alteration of stress physiology in captivity. To address these issues, we examined corticosterone (CORT) and heterophil to lymphocyte (H:L) ratios in two ecotypes of the garter snake Thamnophis elegans. We found that CORT and H:L ratios were not correlated within individuals, and both variables showed little or no repeatability over a period of months. CORT levels, but not H:L ratios, were higher for individuals sampled after 10min from the time of capture. However, both variables showed similar patterns of ecotypic variation, and both increased over time in gravid females maintained in captivity for four months. We suggest that CORT and H:L ratios are both useful, but disparate indices of stress in this species, and may show complex relationships to each other and to ecological and anthropogenic variables. Copyright © 2014 Elsevier Inc. All rights reserved.

Individual tree diameter increment model for managed even-aged stands of ponderosa pine throughout the western United States using a multilevel linear mixed effects model

Treesearch

Fabian C.C. Uzoh; William W. Oliver

2008-01-01

A diameter increment model is developed and evaluated for individual trees of ponderosa pine throughout the species range in the United States using a multilevel linear mixed model. Stochastic variability is broken down among period, locale, plot, tree and within-tree components. Covariates acting at tree and stand level, as breast height diameter, density, site index...

The Association Between County-Level Injury Rates and Racial Segregation Revisited: A Multilevel Analysis

PubMed Central

Sauber-Schatz, Erin K.; Barbour, Kamil E.; Li, Wei

2009-01-01

Objectives. We investigated whether within-county racial segregation was associated with increased odds of violent injury beyond individual risk. Methods. In a cross-sectional study, data on 75 310 patients admitted with an injury to Pennsylvania hospitals from 1997 to 1999 were analyzed to determine the association between county-level racial segregation and violent injury. We used multilevel analysis to adjust for individual- and county-level factors. Principal components analysis allowed us to separate the effect of segregation from other county-level variables. Results. After adjustment, greater segregation was associated with increased odds of violent injury among Whites (odds ratio [OR] = 1.20; 95% confidence interval [CI] = 1.11, 1.30) and non-Whites (OR = 1.45; 95% CI = 1.28, 1.64). The association was stronger for non-Whites. Conclusions. Our results suggested that living in a county with high levels of racial segregation was associated with increased odds of violence not explained by an individual's own risk. These findings represent an important step in understanding the nature of observed links between race and violence. Future work should develop prevention strategies that simultaneously target community and individual risks. PMID:19150902

Level of Recall, Retrieval Speed, and Variability on the Cued-Recall Retrieval Speed Task (CRRST) in Individuals with Amnestic Mild Cognitive Impairment

PubMed Central

Ramratan, Wendy S.; Rabin, Laura A.; Wang, Cuiling; Zimmerman, Molly E.; Katz, Mindy J.; Lipton, Richard B.; Buschke, Herman

2013-01-01

Individuals with amnestic mild cognitive impairment (aMCI) show deficits on traditional episodic memory tasks and reductions in speed of performance on reaction time tasks. We present results on a novel task, the Cued-Recall Retrieval Speed Test (CRRST), designed to simultaneously measure level and speed of retrieval. 390 older adults (mean age of 80.2 years), learned 16 words based on corresponding categorical cues. In the retrieval phase, we measured accuracy (% correct) and retrieval speed/reaction time (RT; time from cue presentation to voice onset of a correct response) across 6 trials. Compared to healthy elderly adults (HEA, n = 303), those with aMCI (n = 87) exhibited poorer performance in retrieval speed (difference = −0.13, p<.0001) and accuracy on the first trial (difference = −0.19, p<.0001), and their rate of improvement in retrieval speed was slower over subsequent trials. Those with aMCI also had greater within-person variability in processing speed (variance ratio = 1.22, p = 0.0098) and greater between-person variability in accuracy (variance ratio = 2.08, p = 0.0001) relative to HEA. Results are discussed in relation to the possibility that computer-based measures of cued-learning and processing speed variability may facilitate early detection of dementia in at-risk older adults. PMID:22265423

[Inter-and intra-operator variability in the analysis of semen parameters: results from a quality control program].

PubMed

Daoud, Salima; Chakroun-Feki, Nozha; Sellami, Afifa; Ammar-Keskes, Leila; Rebai, Tarek

2016-01-01

Semen analysis is a key part of male infertility investigation. The necessity of quality management implementation in the andrology laboratory has been recognized in order to ensure the reliability of its results. The aim of this study was to evaluate intra- and inter-individual variability in the assessment of semen parameters in our laboratory through a quality control programme. Four participants from the laboratory with different experience levels have participated in this study. Semen samples of varying quality were assessed for sperm motility, concentration and morphology and the results were used to evaluate inter-participant variability. In addition, replicates of each semen sample were analyzed to determine intra-individual variability for semen parameters analysis. The average values of inter-participant coefficients of variation for sperm motility, concentration and morphology were 12.8%, 19.8% and 48.9% respectively. The mean intra-participant coefficients of variation were, respectively, 6.9%, 12.3% and 42.7% for sperm motility, concentration and morphology. Despite some random errors of under- or overestimation, the overall results remained within the limits of acceptability for all participants. Sperm morphology assessment was particularly influenced by the participant's level of experience. The present data emphasize the need for appropriate training of the laboratory staff and for regular participation in internal quality control programmes in order to improve the reliability of laboratory results.

Spatial and Temporal Dynamics in Air Pollution Exposure Assessment

PubMed Central

Dias, Daniela; Tchepel, Oxana

2018-01-01

Analyzing individual exposure in urban areas offers several challenges where both the individual’s activities and air pollution levels demonstrate a large degree of spatial and temporal dynamics. This review article discusses the concepts, key elements, current developments in assessing personal exposure to urban air pollution (seventy-two studies reviewed) and respective advantages and disadvantages. A new conceptual structure to organize personal exposure assessment methods is proposed according to two classification criteria: (i) spatial-temporal variations of individuals’ activities (point-fixed or trajectory based) and (ii) characterization of air quality (variable or uniform). This review suggests that the spatial and temporal variability of urban air pollution levels in combination with indoor exposures and individual’s time-activity patterns are key elements of personal exposure assessment. In the literature review, the majority of revised studies (44 studies) indicate that the trajectory based with variable air quality approach provides a promising framework for tackling the important question of inter- and intra-variability of individual exposure. However, future quantitative comparison between the different approaches should be performed, and the selection of the most appropriate approach for exposure quantification should take into account the purpose of the health study. This review provides a structured basis for the intercomparing of different methodologies and to make their advantages and limitations more transparent in addressing specific research objectives. PMID:29558426

Peer social support is associated with recent HIV testing among young black men who have sex with men.

PubMed

Scott, Hyman M; Pollack, Lance; Rebchook, Gregory M; Huebner, David M; Peterson, John; Kegeles, Susan M

2014-05-01

Resiliency factors such as social support have been associated with more frequent HIV testing among MSM. We examined the association between social support and delayed HIV testing in the context of structural discrimination and individual factors among young Black MSM. We combined two independent cross-sectional samples recruited 1 year apart from a venue-based, modified time-location sampling study of young Black MSM aged 18-29 years in the US South. Our subsample (N = 813) was men who self-reported not being HIV positive and who indicated they had one or more male sex partners in the past 2 months. Using a social epidemiology framework we estimated associations of structural (racism and homophobia), social (social support from other Black MSM friends) and individual factors with delayed HIV testing (>6 months ago) using logistic regression. Bivariate analyses demonstrated that individual level variables as well as experiences of racism (OR 1.20, 95% CI 1.02-1.41) and homophobia (OR 1.49, 95 % CI 1.02-2.17) were associated with higher risk of delayed HIV testing. Receiving social support from other Black MSM friends was associated with lower risk of delayed HIV testing (OR 0.80, 95 % CI 0.67-0.95). In multivariable models, social support remained significantly associated with lower risk of delayed HIV testing after inclusion of structural and individual level variables. Social support has a positive and robust association with HIV testing among young Black MSM. Whether community building and development of resiliency factors can overcome structural, social, and individual-level barriers to HIV prevention and care for young Black MSM warrants further study.

A Multilevel Analysis of the Compositional and Contextual Association of Social Capital and Subjective Well-Being in Seoul, South Korea

ERIC Educational Resources Information Center

Han, Sehee; Kim, Heaseung; Lee, Hee-Sun

2013-01-01

The purpose of this study is to examine the association between social capital and subjective well-being (life satisfaction) by using multilevel analysis considering both individual and area-level social capital while adjusting for various control variables at multiple-levels in Seoul, South Korea. The data was from the 2010 (Wave 2) Seoul Welfare…

REGIONAL VARIATIONS IN INFANT AND CHILD MORTALITY IN NIGERIA: A MULTILEVEL ANALYSIS.

PubMed

Adedini, Sunday A; Odimegwu, Clifford; Imasiku, Eunice N S; Ononokpono, Dorothy N; Ibisomi, Latifat

2015-03-01

There are substantial regional disparities in under-five mortality in Nigeria, and evidence suggests that both individual- and community-level characteristics have an influence on health outcomes. Using 2008 Nigeria Demographic and Health Survey data, this study (1) examines the effects of individual- and community-level characteristics on infant/child mortality in Nigeria and (2) determines the extent to which characteristics at these levels influence regional variations in infant/child mortality in the country. Multilevel Cox proportional hazard analysis was performed on a nationally representative sample of 28,647 children nested within 18,028 mothers of reproductive age, who were also nested within 886 communities. The results indicate that community-level variables (such as region, place of residence, community infrastructure, community hospital delivery and community poverty level) and individual-level factors (including child's sex, birth order, birth interval, maternal education, maternal age and wealth index) are important determinants of infant/child mortality in Nigeria. For instance, the results show a lower risk of death in infancy for children of mothers residing in communities with a high proportion of hospital delivery (HR: 0.70, p < 0.05) and for children whose mothers had secondary or higher education (HR: 0.84, p < 0.05). Although community factors appear to influence the association between individual-level factors and death during infancy and childhood, the findings consistently indicate that community-level characteristics are more important in explaining regional variations in child mortality, while individual-level factors are more important for regional variations in infant mortality. The results of this study underscore the need to look beyond the influence of individual-level factors in addressing regional variations in infant and child mortality in Nigeria.

Area-level poverty and preterm birth risk: A population-based multilevel analysis

PubMed Central

DeFranco, Emily A; Lian, Min; Muglia, Louis A; Schootman, Mario

2008-01-01

Background Preterm birth is a complex disease with etiologic influences from a variety of social, environmental, hormonal, genetic, and other factors. The purpose of this study was to utilize a large population-based birth registry to estimate the independent effect of county-level poverty on preterm birth risk. To accomplish this, we used a multilevel logistic regression approach to account for multiple co-existent individual-level variables and county-level poverty rate. Methods Population-based study utilizing Missouri's birth certificate database (1989–1997). We conducted a multilevel logistic regression analysis to estimate the effect of county-level poverty on PTB risk. Of 634,994 births nested within 115 counties in Missouri, two levels were considered. Individual-level variables included demographics factors, prenatal care, health-related behavioral risk factors, and medical risk factors. The area-level variable included the percentage of the population within each county living below the poverty line (US census data, 1990). Counties were divided into quartiles of poverty; the first quartile (lowest rate of poverty) was the reference group. Results PTB < 35 weeks occurred in 24,490 pregnancies (3.9%). The rate of PTB < 35 weeks was 2.8% in counties within the lowest quartile of poverty and increased through the 4th quartile (4.9%), p < 0.0001. High county-level poverty was significantly associated with PTB risk. PTB risk (< 35 weeks) was increased for women who resided in counties within the highest quartile of poverty, adjusted odds ratio (adjOR) 1.18 (95% CI 1.03, 1.35), with a similar effect at earlier gestational ages (< 32 weeks), adjOR 1.27 (95% CI 1.06, 1.52). Conclusion Women residing in socioeconomically deprived areas are at increased risk of preterm birth, above other underlying risk factors. Although the risk increase is modest, it affects a large number of pregnancies. PMID:18793437

Area-level poverty and preterm birth risk: a population-based multilevel analysis.

PubMed

DeFranco, Emily A; Lian, Min; Muglia, Louis A; Schootman, Mario

2008-09-15

Preterm birth is a complex disease with etiologic influences from a variety of social, environmental, hormonal, genetic, and other factors. The purpose of this study was to utilize a large population-based birth registry to estimate the independent effect of county-level poverty on preterm birth risk. To accomplish this, we used a multilevel logistic regression approach to account for multiple co-existent individual-level variables and county-level poverty rate. Population-based study utilizing Missouri's birth certificate database (1989-1997). We conducted a multilevel logistic regression analysis to estimate the effect of county-level poverty on PTB risk. Of 634,994 births nested within 115 counties in Missouri, two levels were considered. Individual-level variables included demographics factors, prenatal care, health-related behavioral risk factors, and medical risk factors. The area-level variable included the percentage of the population within each county living below the poverty line (US census data, 1990). Counties were divided into quartiles of poverty; the first quartile (lowest rate of poverty) was the reference group. PTB < 35 weeks occurred in 24,490 pregnancies (3.9%). The rate of PTB < 35 weeks was 2.8% in counties within the lowest quartile of poverty and increased through the 4th quartile (4.9%), p < 0.0001. High county-level poverty was significantly associated with PTB risk. PTB risk (< 35 weeks) was increased for women who resided in counties within the highest quartile of poverty, adjusted odds ratio (adj OR) 1.18 (95% CI 1.03, 1.35), with a similar effect at earlier gestational ages (< 32 weeks), adj OR 1.27 (95% CI 1.06, 1.52). Women residing in socioeconomically deprived areas are at increased risk of preterm birth, above other underlying risk factors. Although the risk increase is modest, it affects a large number of pregnancies.

Fragile and Enduring Positive Affect: Implications for Adaptive Aging.

PubMed

Ong, Anthony D; Ram, Nilam

2017-01-01

There is robust evidence linking interindividual differences in positive affect (PA) with adaptive psychological and physical health outcomes. However, recent research has suggested that intraindividual variability or fluctuations in PA states over time may also be an important predictor of individual health outcomes. Here, we report on research that focuses on PA level and various forms of PA dynamics (variability, instability, inertia, and reactivity) in relation to health. PA level refers to the average level of positive feelings. In contrast, PA dynamics refer to short-term changes in PA that unfold over time. We discuss how consideration of both PA level and PA dynamics can provide a framework for reconciling when high PA is conducive or detrimental to health. We conclude that more work on PA dynamics is needed, especially in combination with PA level, and suggest productive questions for future inquiry in this area. © 2016 S. Karger AG, Basel.

Social capital and leisure time physical activity: a population based multilevel analysis in Malmö, Sweden

PubMed Central

Lindstrom, M; Moghaddassi, M; Merlo, J

2003-01-01

Objective: To investigate the influence of social capital and individual factors on the level of leisure time physical inactivity in the neighbourhoods. Methods: The public health survey in Malmö 1994 is a cross sectional study. A total of 5600 people aged 20–80 years were invited to answer a postal questionnaire. The participation rate was 71%. A multilevel logistic regression model, with individuals at the first level and neighbourhoods at the second, was performed. The effect (intra-area correlation, cross level modification, and odds ratios) was analysed of individual and neighbourhood (the 1993 migration out of an area as a proxy for social capital) factors on leisure time physical inactivity after adjustment for individual factors. Results: Neighbourhood factors accounted for 5.0% of the crude total variance in physical inactivity. This effect was significantly reduced when the individual factors, especially country of origin, education, and social participation, were included in the model. In contrast, it was not reduced by the introduction of the contextual social capital variable. Conclusion: This study suggests that in the neighbourhoods of Malmö leisure time physical inactivity is mainly affected by individual factors. PMID:12490644

Heart rate variability based on risk stratification for type 2 diabetes mellitus.

PubMed

Silva-E-Oliveira, Julia; Amélio, Pâmela Marina; Abranches, Isabela Lopes Laguardia; Damasceno, Dênis Derly; Furtado, Fabianne

2017-01-01

To evaluate heart rate variability among adults with different risk levels for type 2 diabetes mellitus. The risk for type 2 diabetes mellitus was assessed in 130 participants (89 females) based on the questionnaire Finnish Diabetes Risk Score and was classified as low risk (n=26), slightly elevated risk (n=41), moderate risk (n=27) and high risk (n=32). To measure heart rate variability, a heart-rate monitor Polar S810i® was employed to obtain RR series for each individual, at rest, for 5 minutes, followed by analysis of linear and nonlinear indexes. The groups at higher risk of type 2 diabetes mellitus had significantly lower linear and nonlinear heart rate variability indexes. The individuals at high risk for type 2 diabetes mellitus have lower heart rate variability. Avaliar a variabilidade da frequência cardíaca em adultos com diferentes níveis de risco para diabetes mellitus tipo 2. O grau de risco para diabetes mellitus tipo 2 de 130 participantes (41 homens) foi avaliado pelo questionário Finnish Diabetes Risk Score. Os participantes foram classificados em baixo risco (n=26), risco levemente elevado (n=41), risco moderado (n=27) e alto risco (n=32). Para medir a variabilidade da frequência cardíaca, utilizou-se o frequencímetro Polar S810i® para obter séries de intervalo RR para cada indivíduo, em repouso, durante 5 minutos; posteriormente, realizou-se análise por meio de índices lineares e não-lineares. O grupo com maior risco para diabetes mellitus tipo 2 teve uma diminuição significante nos índices lineares e não-lineares da variabilidade da frequência cardíaca. Os resultados apontam que indivíduos com risco alto para diabetes mellitus tipo 2 tem menor variabilidade da frequência cardíaca. To evaluate heart rate variability among adults with different risk levels for type 2 diabetes mellitus. The risk for type 2 diabetes mellitus was assessed in 130 participants (89 females) based on the questionnaire Finnish Diabetes Risk Score and was classified as low risk (n=26), slightly elevated risk (n=41), moderate risk (n=27) and high risk (n=32). To measure heart rate variability, a heart-rate monitor Polar S810i® was employed to obtain RR series for each individual, at rest, for 5 minutes, followed by analysis of linear and nonlinear indexes. The groups at higher risk of type 2 diabetes mellitus had significantly lower linear and nonlinear heart rate variability indexes. The individuals at high risk for type 2 diabetes mellitus have lower heart rate variability.

Association between subjective memory complaints and depressive symptoms after adjustment for genetic and family environmental factors in a Japanese twin study.

PubMed

Tanaka, Haruka; Ogata, Soshiro; Omura, Kayoko; Honda, Chika; Kamide, Kei; Hayakawa, Kazuo

2016-03-01

The aim of this study was to investigate the association between subjective memory complaints (SMCs) and depressive symptoms, with and without adjustment for genetic and family environmental factors. We conducted a cross-sectional study using twins and measured SMCs and depressive symptoms as outcomes and explanatory variables, respectively. First, we performed regression analyses using generalized estimating equations to investigate the associations between SMCs and depressive symptoms without adjustment for genetic and family environmental factors (individual-level analyses). We then performed regression analyses for within-pair differences using monozygotic (MZ) and dizygotic (DZ) twin pairs and MZ twin pairs to investigate these associations with adjustment for genetic and family environmental factors by subtracting the values of one twin from those of co-twin variables (within-pair level analyses). Therefore, differences between the associations at individual- and within-pair level analyses suggested confounding by genetic factors. We included 556 twins aged ≥ 20 years. In the individual-level analyses, SMCs were significantly associated with depressive symptoms in both males and females [standardized coefficients: males, 0.23 (95% CI 0.08-0.38); females, 0.35 (95% CI 0.23-0.46)]. In the within-pair level analyses using MZ and same-sex DZ twin pairs, SMCs were significantly associated with depressive symptoms. In the within-pair level analyses using the MZ twin pairs, SMCs were significantly associated with depressive symptoms [standardized coefficients: males, 0.32 (95% CI 0.08-0.56); females, 0.24 (95% CI 0.13-0.42)]. This study suggested that SMCs were significantly associated with depressive symptoms after adjustment for genetic and family environmental factors.

Predicting Stress Related to Basic Needs and Safety in Darfur Refugee Camps: A Structural and Social Ecological Analysis

PubMed Central

RASMUSSEN, ANDREW; ANNAN, JEANNIE

2013-01-01

The research on the determinants of mental health among refugees has been largely limited to traumatic events, but recent work has indicated that the daily hassles of living in refugee camps also play a large role. Using hierarchical linear modelling to account for refugees nested within camp blocks, this exploratory study attempted to model stress surrounding safety and acquiring basic needs and functional impairment among refugees from Darfur living in Chad, using individual-level demographics (e.g., gender, age, presence of a debilitating injury), structural factors (e.g., distance from block to distribution centre), and social ecological variables (e.g., percentage of single women within a block). We found that stress concerning safety concerns, daily hassles, and functional impairment were associated with several individual-level demographic factors (e.g., gender), but also with interactions between block-level and individual-level factors as well (e.g., injury and distance to distribution centre). Findings are discussed in terms of monitoring and evaluation of refugee services. PMID:23626407

Predicting Stress Related to Basic Needs and Safety in Darfur Refugee Camps: A Structural and Social Ecological Analysis.

PubMed

Rasmussen, Andrew; Annan, Jeannie

2010-03-01

The research on the determinants of mental health among refugees has been largely limited to traumatic events, but recent work has indicated that the daily hassles of living in refugee camps also play a large role. Using hierarchical linear modelling to account for refugees nested within camp blocks, this exploratory study attempted to model stress surrounding safety and acquiring basic needs and functional impairment among refugees from Darfur living in Chad, using individual-level demographics (e.g., gender, age, presence of a debilitating injury), structural factors (e.g., distance from block to distribution centre), and social ecological variables (e.g., percentage of single women within a block). We found that stress concerning safety concerns, daily hassles, and functional impairment were associated with several individual-level demographic factors (e.g., gender), but also with interactions between block-level and individual-level factors as well (e.g., injury and distance to distribution centre). Findings are discussed in terms of monitoring and evaluation of refugee services.

Predicting Spouses Perceptions of Their Parenting Alliance

ERIC Educational Resources Information Center

Hughes, Farrah M.; Gordon, Kristina Coop; Gaertner, Lowell

2004-01-01

This study used marital and individual-level variables to predict spouses perceived parenting alliance. One hundred married couples completed measures of parenting alliance, marital consensus, marital power, and depression. Analyses revealed that marital consensus was a significant predictor of parenting alliance for both parents, and that…

Weather, Climate, and You.

ERIC Educational Resources Information Center

Blai, Boris, Jr.

Information from the American Institute of Medical Climatologists on human responses to weather and climatic conditions, including clouds, winds, humidity, barometric pressure, heat, cold, and other variables that may exert a pervasive impact on health, behavior, disposition, and the level of efficiency with which individuals function is reviewed.…

Intraindividual change and variability in daily stress processes: Findings from two measurement-burst diary studies

PubMed Central

Sliwinski, Martin J.; Almeida, David M.; Smyth, Joshua; Stawski, Robert S.

2010-01-01

There is little longitudinal information on aging-related changes in emotional responses to negative events. The present manuscript examined intraindividual change and variability in the within-person coupling of daily stress and negative affect (NA) using data from two-measurement burst daily diary studies. Three main findings emerged. First, average reactivity to daily stress increased longitudinally, and this increase was evident across most the adult lifespan. Second, individual differences in emotional reactivity to daily stress exhibited long-term temporal stability, but this stability was greatest in midlife and decreased in old age. And third, reactivity to daily stress varied reliably within-persons (across-time), with individual exhibiting higher levels of reactivity during times when reporting high levels of global subject stress in previous month. Taken together, the present results emphasize the importance of modeling dynamic psychosocial and aging processes that operate across different time scales for understanding age-related changes in daily stress processes. PMID:20025399

Effects of co-exposure to imidacloprid and gibberellic acid on redox status, kidney variables and histopathology in adult rats.

PubMed

Lafi, Bornia; Chaâbane, Mariem; Elwej, Awatef; Grati, Malek; Jamoussi, Kamel; Mnif, Hela; Boudawara, Tahia; Ketata Bouaziz, Hanen; Zeghal, Najiba

2018-05-01

Data on the individual nephrotoxic effects of imidacloprid (IMI) and gibberellic acid (GA 3 ) are scarce. Moreover, there is a lack of information about their combined effects on the renal tissue. Our study investigated the effects of IMI and GA 3 separately or together on rats kidney. IMI (64 mg/kg bw) was given for 3 weeks by gavage either individually or in combination with GA 3 (200 mg/L) via drinking water. IMI associated or no with GA 3 increased the levels of kidney malondialdehyde, advanced oxidation protein products, protein carbonyls and metallothionein, plasma creatinine, urea, blood urea nitrogen and lactate dehydrogenase activity. A decline of kidney uric acid level and antioxidant status was also observed. All these changes were supported by histopathological observations. Our results highlighted the role of IMI and/or GA 3 -induced nephrotoxicity. Co-exposure to IMI and GA 3 exhibited synergism in biochemical kidney variables and histopathology and antagonism in physical and morphological parameters.

Association between neighbourhood fast-food and full-service restaurant density and body mass index: a cross-sectional study of Canadian adults.

PubMed

Hollands, Simon; Campbell, M Karen; Gilliland, Jason; Sarma, Sisira

2014-05-07

Frequent fast-food consumption is a well-known risk factor for obesity. This study sought to determine whether the availability of fast-food restaurants has an influence on body mass index (BMI). BMI and individual-level confounding variables were obtained from the 2007-08 Canadian Community Health Survey. Neighbourhood socio-demographic variables were acquired from the 2006 Canadian Census. The geographic locations of all restaurants in Canada were assembled from a validated business registry database. The density of fast-food, full-service and non-chain restaurants per 10,000 individuals was calculated for respondents' forward sortation area. Multivariable regression analyses were conducted to analyze the association between restaurant density and BMI. Fast-food, full-service and non-chain restaurant density variables were statistically significantly associated with BMI. Fast-food density had a positive association whereas full-service and non-chain restaurant density had a negative association with BMI (additional 10 fast-food restaurants per capita corresponded to a weight increase of 1 kilogram; p<0.001). These associations were primarily found in Canada's major urban jurisdictions. This research was the first to investigate the influence of fast-food and full-service restaurant density on BMI using individual-level data from a nationally representative Canadian survey. The finding of a positive association between fast-food restaurant density and BMI suggests that interventions aiming to restrict the availability of fast-food restaurants in local neighbourhoods may be a useful obesity prevention strategy.

Team climate at Antarctic research stations 1996-2000: leadership matters.

PubMed

Schmidt, Lacey L; Wood, JoAnna; Lugg, Desmond J

2004-08-01

The popular assumption is that extreme environments induce a climate of hostility, incompatibility, and tension by intensifying differences and disagreements among team members. Team members' perceptions of team climate are likely to change over time in an extreme environment, and thus team climate should be considered as a dynamic outcome variable resulting from multiple factors. In order to explore team climate as a dynamic outcome, we explored whether variables at multiple levels of analysis contributed to team climate over time for teams living and working in Antarctica. Data for this study were collected from volunteers involved in Australian National Antarctic Research Expeditions conducted from 1996 to 2000. Multilevel analysis was used to partition and estimate the variance in team climate and to explore factors explaining variance at the group/team, individual, and weekly levels. Most of the variance in perceptions of team climate was at the individual level (57%). Team climate had less variance at the group level (16%) and at the weekly level (26%). Results indicated that perceived leadership effectiveness was significantly related to team climate. Perceived leadership effectiveness accounted for an estimated 77% of the group level variance, which equated to 14% of the overall variance in team climate. Our results suggest that exploring the characteristics and behaviors that constitute effective leadership would contribute to a more complete and useful picture of team climate, as well as guide selection research.